The five most pervasive anthropogenic threats to biodiversity are over-exploitation, habitat changes, climate change, invasive species, and pollution. Since all of these threats can affect intraspecific biodiversity—including genetic variation within populations—humans have the potential to induce contemporary microevolution in wild populations. We highlight recent empirical studies that have explored the effects of these anthropogenic threats to intraspecific biodiversity in the wild. We conclude that it is critical that we move towards a predictive framework that integrates a better understanding of contemporary microevolution to multiple threats to forecast the fate of natural populations in a changing world. The human footprint on our planet is increasing at an unprecedented rate . It has Organisms can respond most rapidly to environmental  change via plasticity or relocation. Phenotypic plasticity is the capacity of a genotype to produce different phenotypes in response to environmental changes . For exaHumans are considered one of the major selective forces shaping species’ traits, often causing faster phenotypic change than many natural drivers –13, and Human activities now impose the dominant pressures affecting the mortality and reproductive schedules of many species . AccordiOvis canadensis; Fig. Over-exploitation is one of the main threats to biodiversity—humans often act as “super-predators” . While tMelitaea cinxia) revealed that populations inhabiting highly fragmented landscapes had significantly reduced genetic diversity before extinction [Loss of habitat, modifications in land use, degradation and fragmentation of habitat patches, and the increasing footprint of human infrastructure (hereafter referred to as “habitat change”) can all reduce population size and impede connectivity among populations. Habitat changes therefore impact effective population size, dispersal, and gene flow, which have significant implications for microevolutionary dynamics –38. Redutinction . Althougtinction . Howevertinction . Other ftinction .Chionomys nivalis), there has been microevolution towards lower body mass. In this case, there was an adaptive response to viability selection favoring juveniles that complete their development early and become relatively small adults. This selection recently intensified due to a shorter snow-free season, a consequence of changes in snowfall patterns [Recent changes in climate  have propatterns . This suGenetic changes in response to pollution are also likely to be widespread based on available empirical evidence . Indeed,Rhinella marina). The cane toad invasion is characterized by evolution of growth and dispersal rates of the invader as well as behavioral and morphological changes in the native taxa [Microevolution by invasive species, and by native species in response to invasion, has also been documented , 58–60. Although some studies convincingly demonstrate how human-driven environmental changes can impact evolutionary dynamics in the wild, there is clearly a considerable burden of proof that needs to be met in order to unequivocally demonstrate microevolution . This maHansen et al.  proposedDaphnia ambigua revealed that populations exposed to harmful levels of copper and cadmium evolved greater susceptibility to those chemicals [Microevolutionary responses to human-driven environmental changes are possible and, in some cases, these changes can be adaptive if they allow organisms to cope with new environmental conditions. Evolutionary changes in life-history, morphological, and behavioral traits in response to human activities may also move correlated traits away from their naturally selected optima. Given that local adaptations are widespread in nature , human-dhemicals . While tGenomics provides a critically important set of tools for detecting, monitoring, and predicting the evolutionary consequences of human activity on wild populations at a molecular level , 80, 81.Biston betularia) has recently been mapped to the insertion of a transposable element into the first intron of a gene that plays an important role in cell-cycle regulation during early wing disc development [This demonstration requires the identification of loci significantly associated with environmental  and/or trait variation (QTL mapping or genome-wide association) linked to variability in individual fitness or coupled with observed changes in allele frequency over time. This can be achieved through typing historical samples or using samples collected across replicated spatial–environmental gradients. Here it is critical that changes over time or space have adequately controlled for confounding effects of drift and spatial autocorrelation . Ideallyelopment .Functional analyses are, however, not always feasible or even possible in some systems and, with respect to validation, it is also possible that micro-evolutionary changes at the genomic level may be less repeatable and therefore predictable than they are at the phenotypic level due to the complexity of genomic architectures , 93. FurDetecting microevolution is only a starting point—we need tools and approaches for monitoring the rate of change  and predGiven increasing evidence of trait changes driven by human activity, it is critical to document the consequences of trait changes (plastic or genetic) on population dynamics, community, and ecosystem function in wild species, especially those under human threats. For example, documenting eco-evolutionary dynamics, such as whether evolutionary rescue occurs frequently in nature, is central to understanding how species may cope with large-scale human-driven environmental changes characteristic of the Anthropocene. A recent review by Mimura et al. underlined the importance of understanding and monitoring the effect of human-driven changes on intraspecific variation—a major component of biodiversity . HoweverA potentially good starting point is to investigate the consequence of phenotypic changes at higher levels of biological organization and, in parallel, try to evaluate whether those trait changes are driven by genetic changes or plasticity. Indeed, several researchers have argued that trait changes caused by human activity may be shaping ecological dynamics on a global scale . Since tAnother useful avenue may be to use intraspecific genetic and phenotypic changes to monitor human impacts on wild populations . Indeed,It is clear that human activity has profound effects on the eco-evolutionary dynamics of wild populations via novel and strong selection pressures, and populations affected by these pressures show evidence of rapid phenotypic change. While the prerequisites for evolutionary response are often present in human-altered environments, the extent to which these changes generally represent microevolution versus plasticity is uncertain. A recent review found that global levels of threat are increasing by 1 to 2% per decade for populations of birds and mammals where systematic monitoring data are available . Based o


Brachyramphus marmoratus) is a declining seabird that is well-known for nesting in coastal old-growth forests in the Pacific Northwest. Most studies of habitat selection have focused on modeling terrestrial nesting habitat even though marine habitat is believed to be a major contributor to population declines in some regions. To address this information gap, we conducted a 5-year study of marine resource selection by murrelets in Washington, which contains a population experiencing the steepest documented declines and where marine habitat is believed to be compromised. Across five years we tracked 157 radio-tagged murrelets during the breeding season (May to August), and used discrete choice models to examine habitat selection. Using an information theoretic approach, our global model had the most support, suggesting that murrelet resource selection at-sea is affected by many factors, both terrestrial and marine. Locations with higher amounts of nesting habitat  that were closer to shore  and in cool waters  with low footprint  had higher probabilities of use. While past conservation efforts have focused on protecting terrestrial nesting habitat, we echo many past studies calling for future efforts to protect marine habitat for murrelets, as the current emphasis on terrestrial habitat alone may be insufficient for conserving populations. In particular, marine areas in close proximity to old-growth nesting habitat appear important for murrelets during the breeding season and should be priorities for protection.The marbled murrelet ( Brachyramphus marmoratus) is a federally threatened seabird that requires two fundamentally different habitats for breeding. Foraging occurs at sea because murrelets are pursuit-diving seabirds whose primary prey are small schooling fish and large zooplankton. However, coastal, old-growth coniferous forests are used for nesting in much of their range. Like many Alcids, marbled murrelets do not build nests and instead rely on naturally deposited materials for a nest platform. Unlike other alcids, however, in the marbled murrelet a single egg is typically laid directly on a large, mossy limb in the forest canopy. In most cases, only large, old trees have limbs of sufficient diameter for these unusual nests.The marbled murrelet  and in compliance with the Ornithological Council Guidelines for the Use of Wild Birds in Research . ScientiWe conducted this study in northwestern Washington State  and southwestern British Columbia  . We wereWe located radio-tagged murrelets using aerial tracking from fixed wing aircraft. We initiated searches within three days after the first murrelet was tagged in each year. We ended searches after the last known nest had fledged or failed and when significant numbers of transmitters were no longer detectable within our study area, indicating post-breeding dispersal or transmitter battery failure. Weather permitting, we conducted tracking flights daily. Tracking flights lasted for up to ~5 hours until either all birds had been located or the aircraft needed refueling. Aerial searches focused on marine areas, but also included terrestrial areas to locate nest sites of breeding murrelets. If an individual murrelet was not located at-sea or on an inland nest for ~2–3 consecutive days, we expanded our search area to find the missing bird and generally focused on areas beyond the location that the missing murrelet was last detected.When a murrelet’s radio signal was detected from the air, pilots circled over the transmitter and used a GPS unit to mark the location from which they heard the loudest radio signal. Tests with stationary transmitters indicated that location accuracy from aircraft was 385 m on average . We omitted all telemetry locations obtained at night (defined by civil twilight on each day) because past research indicates murrelets do not actively feed at night  and we wAmmodytes hexapterus), anchovy (Engraulis mordax), herring (Chulpea harengus), smelt (Osmeridae), surfperch (Cymatogaster aggregate), juvenile rockfish (Scorpaenidae), and krill (Euphausiids) ).oritized . The connd and 9th in our two variable rankings) compared to other studies.It is important to consider that telemetry location errors in our study had the potential to cause misclassification of some used habitats . We deteLastly, we were unable to determine the behavior of murrelets that were being tracked, which is important for determining whether used habitats are beneficial to animals under study –80. MurrMany past studies have called for the protection of marine areas for marbled murrelets, in addition to the measures currently in place to protect terrestrial nesting habitat , 74, 82.a in Washington. Information on the distribution of forage fish would aid in assessing the extent to which remotely sensed variables can be used to predict murrelet space use or abundance in our study area. Lacking such information, our results suggest murrelet use of some near-shore areas may be limited by nesting habitat availability, shoreline type, and terrestrial footprint, particularly around large metropolitan areas. Future efforts should explore this further, with the possibility of protecting shoreline near the remaining tracts of nesting habitat from a high degree of development. While we recognize the challenges posed by such an approach, we contend that successful conservation of the marbled murrelet is likely to involve challenges irrespective of the approach taken.To further guide management efforts, we also suggest that an important next step is to obtain spatially and temporally explicit information on the distribution of forage fish and other murrelet prey in our study area. Such research should also examine the distributions of forage fish and marine invertebrates relative to remotely sensed SST and chlorophyll-S1 Table(XLSX)Click here for additional data file.


The relative effectiveness of vitamin K antagonists compared with novel oral anticoagulants in treating pulmonary embolism remains unclear. Recent trials comparing the efficacy of vitamin K antagonists with factor Xa inhibitors for the treatment of pulmonary emboli have been non-inferiority studies based primarily on risk reduction (such as bleeding events), rather than resolution of specific diseases such as pulmonary embolism. Consequently, there is a lack of evidence indicating which of these agents are more effective. Here, we present a case where pulmonary emboli were treated with novel oral anticoagulants followed by warfarin to discuss the potential limitations in the use of novel oral anticoagulants as prevention or treatment of thromboembolism and the continued role for warfarin in this setting.A 34-year-old African American woman presented to our clinic with shortness of breath and pleuritic chest pain several months post-surgery. She was identified as having multiple bilateral pulmonary embolisms and was treated with several novel oral anticoagulants, which failed to resolve the clots. Complete resolution was achieved upon switching to warfarin.The patient described in this report failed to respond to novel oral anticoagulant therapy, but her emboli resolved when she was treated with warfarin. This study challenges the notion that factor Xa inhibitors are better alternatives to vitamin K anticoagulants in the treatment of pulmonary emboli based on their safety profile and ease of use alone. As a result, further post-marketing investigations into the efficacy of these agents in the management of pulmonary emboli may be warranted. Venous thromboembolism (VTE) is a condition that comprises deep vein thrombosis (DVT) with or without the presence of systemically circulating emboli; it includes conditions such as pulmonary embolism (PE). Prevention and treatment of VTE are imperative due to the significant morbidity and risk of mortality involved. Currently, agents available to treat this condition are limited and, among these, the mainstay of both prevention and treatment for over 60 years has been warfarin , which is an oral vitamin K antagonist (VKA). However, warfarin treatment is inconvenient due to its increased risk of adverse events , which makes it an undesirable option , 2.In response, new agents were developed to improve patients’ quality of life and to decrease the risk of bleeding in those requiring long-term anticoagulation. One class of these newer agents, the novel oral anticoagulants (NOACs) including direct factor Xa inhibitors (FXaI) and direct thrombin inhibitors, is quickly becoming the standard of care as first-line agents due to clear advantages with regard to monitoring and risks of adverse events. However, at this point, there is limited long-term data to determine all factors for their use in special circumstances. Here we present a case of a medication-compliant patient who experienced recurrent pulmonary emboli, yet failed to resolve these emboli on initial treatment with multiple NOACs, reaching complete resolution of emboli only after being switched to warfarin treatment.2) African American woman with a history of an undefined congenital septal defect, the status of which is post-surgical repair, and congenital clubfoot, who also underwent calcaneal tendon repair in May of 2015. Afterward, she remained sedentary for several weeks and then began to report progressively worsening non-exertional dyspnea that was associated with sharp intermittent chest pain. On 31 May 2015, she presented to her local emergency department for dyspnea on inspiration and “stabbing” pleuritic chest pain at bilateral lung bases. A computed tomography (CT) angiogram of her chest was performed, demonstrating multiple bilateral PEs  2.0–3.0, requiring weekly INR checks with appropriate dosing adjustments. She reported gradual progressive improvement and in March 2016 a CT angiography of her chest was performed with no evidence of pulmonary arterial thrombi or emboli  , 6. BeneHowever, it is important to note that the trials reported to date have largely been non-inferiority studies, not equivalency or superiority studies. Data reported in the EINSTEIN–PE trial showed a downward trend in VTE episodes among those treated with warfarin versus rivaroxaban, but displayed a reduced number of bleeding episodes in the rivaroxaban group as compared with the warfarin group . Most ofIt is clear that non-inferiority studies are useful to determine the general safety profile of a novel therapeutic agent while retaining the efficacy of an accepted therapeutic standard. However, the lack of equivalency or superiority data and the absence of findings in established subsets of affected patients impede a clinician’s ability to critically evaluate what therapeutic agent may be best in treating specific conditions. Trials for new medications allow for the discovery and validation of agents, while decreasing potential risks, but these data should be regarded as tentative until more definitive studies have been performed in large populations, determining where the most benefit can be derived with the least possible risk.It is accepted that common risk factors for clot formation include tobacco use, a history of coagulopathy, and/or the use of oral contraception. The patient in this report was counseled on these risk factors and denied either a history of tobacco use or clotting dysfunction; however, she was determined to be on levonorgestrel-releasing intrauterine system . Although intrauterine devices are impregnated with hormonal contraceptive agents and carry a risk of thrombosis, Skyla was not reported to induce any cases during clinical trials, only as a part of post-marketing studies, and she developed clots after long-term use of this device .Without significant retrospective analyses or randomized prospective trials with subgroup analyses, it is difficult to determine whether VKAs or FXaIs are truly more effective in the treatment of PE. This assessment is especially difficult when taking into account the diagnostic modalities and treatments provided for this patient prior to arrival in our clinic. Although she was initially followed with serial V/Q scans to determine the success of her treatments, the EINSTEIN–PE investigators and our clinic elected to use CT angiography in view of its substantially increased resolution . In addiet al. have reported independently on possible rivaroxaban failure in patients treated during the postpartum period, possibly due to pharmacokinetic alterations seen in the postpartum period that can contribute to decreased drug exposure and reduced anticoagulant efficacy [We suggest that further investigations are needed to establish if novel direct-acting oral anticoagulants are equal to warfarin in the prevention and treatment of VTEs, including DVT and PE. Further, we suggest that practitioners carefully weigh the risks and benefits when selecting these medications. We note that Rudd efficacy . In factefficacy . In pracefficacy .


Accordingly, Whatcott et al. have shown a negative correlation between PDAC-patient median survival and the collagen or hyaluronic acid enrichment of the primary tumor4. At the site of PDAC this fibrosis, or desmoplasia, often creates zones of low oxygen and nutrients resulting from poor vascularization5. Given these microenvironmental constraints and the resulting metabolic pressure, pancreatic tumor cells adapt their metabolism to benefit from available nutrient resources in order to survive and proliferate. This metabolic reprogramming leads to the emergence of aggressive tumor cells and invasive tumors, which are able to disseminate to distal organs including the liver and lung6.The microenvironment of tumors varies between cancer types, and its complex role in tumor propagation contributes to its importance in the field of tumor biology. Tumors with a dense microenvironment express aggressive characteristics that directly impact patient clinical outcomes. In pancreatic ductal adenocarcinoma (PDAC), tumor cells are surrounded by various cellular and acellular components including activated fibroblasts, immune cells, neurons, collagens, fibronectin, and hyaluronan, creating a fibrotic shield that impedes chemotherapeutics delivery to tumor cellsNature Communications7, our study shows an abundance of collagen types I and IV surrounding tumor cells among a variety of extracellular proteins and macromolecules contained in the PDAC microenvironment. Moreover, we observed an upregulation of matrix metalloproteases specific for collagen I and IV degradation as well as an increase of prolidase that hydrolyzes dipeptides with C-terminal proline or hydroxyproline residues, in the tumor compared to normal pancreas. Importantly, prolidase displayed an extracellular localization both in mouse and human PDAC sections. This suggests a potential breakdown of collagen to release proline that could be used as alternative nutrient source by PDAC tumor cells. Supporting this hypothesis, we have demonstrated an increase of proline dehydrogenase 1 (PRODH1), the key enzyme involved in proline catabolism, in mouse and human PDAC compared to normal pancreas. We then questioned whether PDAC cells could scavenge collagens for metabolic purposes and whether nutrient stress conditions promoted this scavenging. We found that PDAC cells increase their uptake of collagen I and IV proportionally to the intensity of the stress associated with glucose and glutamine deprivation. We discovered that upon glucose deprivation macropinocytosis is the main route PDAC cells use to engulf collagen and that blocking this process suppresses their survival. In vivo studies recently published in Nature Medicine by Davidson et al.8 showed that pancreatic tumors exhibit high levels of macropinocytosis and use this process to uptake albumin, the breakdown of which contributes to free amino-acid supply in the tumor. Hence, protein scavenging appears to be an important route for PDAC cells to satisfy their amino-acid demands and macropinocytosis is one of the main process K-ras mutant PDAC cells use to uptake surrounding macromolecules  cycle intermediates in tumor cells under glucose and glutamine limitations at both normoxia and hypoxia. Inhibition of proline degradation not only reduced proline contribution to TCA cycle but also decreased the mitochondrial respiration of PDAC cells. Finally, to determine the contribution of proline to tumor growth, we chose to genetically invalidate PRODH1 in PDAC cells and challenge them to in vitro and in vivo tumorigenic assays. Indeed, PRODH1 inhibition impairs the clonogenic capacities of PDAC cells and drastically limits tumor size in vivo.Our study is notable in its design and use of an experimental approach for in vitro collagen tracing; we cultured PDAC cells on labelled collagen matrix produced by fibroblasts previously supplied with labelled proline. We have shown that, when deprived of glucose or glutamine, tumor cells take up the labelled collagen matrix and extract proline from this collagen. To examine the role of proline in PDAC cells under glucose or glutamine-deprived cell culture contexts, we blocked proline degradation using the competitive inhibitor of PRODH1, deshydroproline. We observed a decrease of cell survival and proliferation, highlighting proline catabolism as a point of metabolic vulnerability that dictates PDAC cell growth. To better understand how proline helps tumor cell survive and proliferate, we carried out follow-up experiments to determine the metabolic contribution of proline in PDAC cells. Indeed, proline tracing in these cells revealed that proline carbons contribute to protein metabolic compartment. Also, we examined the fate of catabolized proline by metabolic tracing of U-Nature Communications11, demonstrates that in the context of breast cancer, proline catabolism contributes to spheroidal growth through PRODH1 activity. Moreover, the pyrroline-5-carboxylate (P5C) reductase 1 responsible for the recycling of the P5C to proline appeared to contribute to the full activity of PRODH1  and its subsequent lysosomal breakdown in metastatic sites . We propose that ECM-derived proline is one of the readily available substrates in tumor cores, which compensates for a lack in glutamine or glucose allowing tumor cell survival and proliferation under extreme metabolic challenge. Proline contribution to TCA metabolism, cellular respiration, or protein biomass identifies new metabolic pathways to be considered as pro-tumorigenic and which to date have been underestimated compared to glutamine or glucose metabolisms, especially in studies exploring PDAC metabolism. Another recent study published by Elia et al., in


While it is commonly believed that animals live longer in zoos than in the wild, this assumption has rarely been tested. We compared four survival metrics  between both sexes of free-ranging and zoo populations of more than 50 mammal species. We found that mammals from zoo populations generally lived longer than their wild counterparts (84% of species). The effect was most notable in species with a faster pace of life  because zoos evidently offer protection against a number of relevant conditions like predation, intraspecific competition and diseases. Species with a slower pace of life  benefit less from captivity in terms of longevity; in such species, there is probably less potential for a reduction in mortality. These findings provide a first general explanation about the different magnitude of zoo environment benefits among mammalian species, and thereby highlight the effort that is needed to improve captive conditions for slow-living species that are particularly susceptible to extinction in the wild. By doing so, zoos achieve a diversity of goals beyond their visitors’ recreation: basic zoological and conservation education reaches 700 million visitors per year all over the worldWhen assessing the justification of holding nondomestic species in zoos, the welfare of the individual animals housed in captivity is a critical ethical issue that has to be weighed against these aims578101212To address this question, we compared a set of survival metrics derived from life tables available from the literature for males and females of free-ranging populations of 59 mammalian species , longevity was higher in zoos than in the wild for both sexes  and 3A. Our findings indicate that, in general, a life in zoos allows mammals to live longer. However, our data suggest that the species-specific pace of life influences the extent to which a given species may benefit from captivity. Species with a faster pace of life typically suffer from high levels of environmentally-driven mortality in the wild including predation19To what extent improvement of captive conditions has already occurred in zoos cannot be evaluated with our data. For long-lived species, we cannot include animals born in recent years because of the need to include only extinct cohorts to avoid overestimating age-specific mortality rates . If we assume that age-specific mortality decreases over time in zoos thanks to improved husbandry conditions, especially in recent years and independently of a species’ pace of life, then the absence of recent cohorts for long-lived species in our analyses might account at least partly for our finding that the survival benefit of living in zoos was less pronounced in long- than in short-lived species. We might expect improved living conditions in zoos to have delayed positive effects in long-lived species. For example, there has been tremendous effort in building new elephant enclosures in a great number of zoos in the last decade  and large-scale studies have been performed on the potential to increase captive elephant welfareOur study refutes previous conclusions that the rate of actuarial senescence of vertebrates is not influenced by captivityex situ insurance populations of such threatened species remains a crucial conservation strategy.Carnivores show enhanced survival in zoos in our study, but are more susceptible to behavioral abnormalitieset al.Mustela vison for which the life table only included 30 individuals, and the highest is observed for males of Oryctolagus cuniculus with a total of 9,020 individuals  modelsHow to cite this article: Tidière, M. et al. Comparative analyses of longevity and senescence reveal variable survival benefits of living in zoos across mammals. Sci. Rep.6, 36361; doi: 10.1038/srep36361 (2016).Publisher’s note: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.


Organoids are derived from human stem cells and retain the genomic background, cellular organization and functionality of their tissue of origin. Thus they have been widely used to characterize stem cell development, numerous cancers and genetic diseases. We believe organoid technology can be harnessed to study host–pathogen interactions resulting in a more physiologically relevant model that yields more predictive data of human infectious diseases than current systems. Here, we highlight recent work and discuss the potential of human stem cell-derived organoids in studying infectious diseases and immunity.For many decades, human infectious diseases have been studied in immortalized cell lines, isolated primary cells from blood and a range of animal hosts. This research has been of fundamental importance in advancing our understanding of host and pathogen responses but remains limited by the absence of multicellular context and inherent differences in animal immune systems that result in altered immune responses. Recent developments in stem cell biology have led to the  Lower respiratory infections, cancers (including those caused by infectious agents), diarrheal diseases and tuberculosis remain among the top 10 causes of death worldwide . Of cruc(1)in vitro culture (with the possibility to differentiate the monocytes to macrophages or dendritic cells); similarly, but in lower numbers, dendritic cells can be purified straight from blood or tissue resident macrophages from certain tissues, e.g., alveolar macrophages from lungs, Purification of peripheral blood mononuclear cells (PBMC’s) from human blood for short term (2) Immortalized MPS-like single cell lines of human or animal origin, e.g., the human monocyte-like THP-1 cell line, the murine macrophage-like J774 cell line,(3) Using animal organisms to study aspects of the system, e.g., non-human primates, zebrafish, mice, humanized mice, cell lineage depleted animals and extrapolating results to humans.in vitro based systems is at a record high. We believe that the future of applied and fundamental research lies in the quickly expanding field of in vitro grown organoids that recapitulate human organs to varying degrees. Organoids bridge the gap between single cell culture and in vivo work, offering ethically obtained functional, multicellular tissue of human origin that provides a more similar in vitro system in which to study multiple components of host–pathogen interactions and drug response.It is key to note that single cell culture and animal models are widely used and have been instrumental in many scientific advancements in fundamental research, drug and vaccine development, infectious, autoimmune and genetic diseases to name a few. Whilst their scientific importance cannot be underestimated, critical questions typically arise relating to the validity of these systems. This is a result of the inherent differences in cellular context (or the lack of it when using primary cells or cell lines), physiology and genetics of different species which influences disease outcome, progression and accurate prediction of human response. The severe effects of such matters become apparent in the fact that pre-clinical animal tests are still failing to predict human pharmacodynamics and toxicity as exemplified by the recent failure of the 2016 phase 1 clinical trial of BIA 10-2474 for neuropathic pain which resulted in the hospitalization of five participants and the death of one . With anin vitro. These organoids are stem cell derived, self –organizing, multi-cellular aggregates that closely recapitulate the function, cellular components and architecture of human tissues. Organoids are cultured in 3D (in extracellular matrix) and reflect the cellular heterogeneity and cellular behavior of tissues in vitro. Unlike cell lines, organoids remain genetically stable for long periods (years) and do not show significant increases in the expression of stress-related genes during extended culture . Organoids that can be cultured from human ASC’s include colon . Intestinal  of humans was first identified in Salmonella enterica serovar Typhi virulence provided the first evidence that infection with this bacteria is a causative agent of gallbladder carcinoma  to continue our research on unraveling the mechanisms behind ESX-1 dependent translocation and its function during infection (Bacterial pathogens are also being increasingly studied in organoids. Organoid based studies into arcinoma . S. Typh cancers . Similarls exist , whilst nfection  – with pnfection .Nippostrongylus brasiliensis (Cyclospora sp., Cryptosporidium sp. and Giardia sp. (Studying interactions between human hosts and their protozoan parasites has been difficult due to a lack of appropriate animal models or due to the difficulty in culturing parasites with obligate human-host specificity. Currently, organoids have been limited to a supportive role to assay the role of tuft cells during infection with the helminth parasite iliensis . Howeverrdia sp. .It is clear that organoids can represent tissue structure and function exceptionally well. Organoid technology is a significant and brilliant advancement in the tools available for scientific research across a wide range of different topics but they remain inherently incomplete- they lack the microenvironment of stroma, vasculature, immune cells and other organ systems that tissues interact with in the body during development and disease. It is also likely that not all developmental stages are currently being represented in a single organoid culture which is particularly relevant if fetal or adult infections are being modeled. Furthermore, certain cell types are not being maintained in organoid cultures due to incorrect signaling resulting in the growth of ‘incomplete’ tissues that compromise the validity of these systems in research.in vitro grown organs. This is currently being accomplished by transplanting induced PSC-derived organoids grown with stromal populations and connecting the endothelial network to a mouse host (Organoid culture techniques are thus in a constant state of evolution; culture conditions are constantly being improved to better support multiple cell types and drive proliferation. Current efforts are also guiding the development of designer matrices such as polyethylene glycol hydrogels that are mechanically more stable and whose composition is defined, unlike the inherently variable, animal sourced and traditionally used extracellular matrix . Better use host , howeverin vitro at an unprecedented level and in a experimentally controllable environment. Immune cells are often the first point of contact during infection, and their response dictates disease outcome. It is thus important to use organoid systems to their full capacity. Therefore, to accurately model both the MPS and infectious disease, we must be sure to include missing but key cell types, even if they are not naturally present using current methods of organoid culture.Most important for studying the MPS in organoids, are advancements relating to co-culturing organoids with cell types that are absent in epithelial structures such as macrophages and dendritic cells. Though currently in its infancy, it is already possible to mix intestinal organoids cultured as normal, with purified cultures of intraepithelial lymphocytes in an extracellular matrix to study their migration against the basal side of the organoids via fluorescent imaging . It is ain vitro has been described, and their use in stem cell development, cancer, infectious diseases, drug screening and transplantation demonstrated. As we get better insight into the culture conditions needed to maintain the multiple cell types and microenvironment associated with human tissues, we gain from being able to recapitulate more of human physiology in vitro. This in turn provides an increasingly suitable and better defined model system for modeling the role of MPS and other cells involved in infection, immunity and inflammation. Organoid systems are also exquisitely suitable for adaptation into diagnostic and screening platforms as they offer an excellent source of readily available human tissue that accurately reflects human responses. Whilst organoids are not without their caveats, we believe they will continue to significantly advance scientific attitudes, fundamental, therapeutic and clinical research for decades more.The beauty of organoids in recapitulating human tissue and function NI conceived the idea, wrote and edited the manuscript. PP contributed ideas and discussion of the manuscript.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.


Political realities and institutional structures are often ignored when gathering evidence to influence population health policies. If these policies are to be successful, social science literature on policy change should be integrated into the population health approach. In this contribution, drawing on the work of John W. Kingdon and related scholarship, we set out to examine how key components of the policy change literature could contribute towards the effective development of population health policies. Shaping policy change would require a realignment of the existing school of thought, where the contribution of population health seems to end at knowledge translation. Through our critical analysis of selected literature, we extend recommendations to advance a burgeoning discussion in adopting new approaches to successfully implement evidence-informed population health policies. Here, we set out to examine how key aspects of the policy change literature, especially the work of John W. Kingdon, could contribute towards developing population health policies by facilitating actor mobilization (Policy Entrepreneurs), enhancing flow of policy perspectives (Ideas), and leveraging historically-constructed structures (Institutions) across jurisdictions. Although our article does not review the entire policy change literature, we believe that our focus on policy entrepreneurs, ideas, and institutions offers major insights into how population health scholars and practitioners could better navigate and impact the policy process.Population health advocates need to become more politically astute and pay more attention to political determinants of health.14 and, more specifically, to the mobilization of specific actors involved in the policy process.15 From experts to interest groups, there are many different types of policy actors but, when the time comes to explain policy change, “policy entrepreneur” is a particularly useful analytical category.16 Policy entrepreneurs are powerful political and social actors who are in the business of articulating specific problems that move in and out of the policy agenda with new or existing policy solutions. In a specific policy area and at particular points in time, elected officials as well as people associated with political parties, interest groups, international organizations, social movements, and think tanks, can all become policy entrepreneurs as they seek to shape the agenda and promote policy solutions to respond to the perceived economic, social, and environmental problems that influence health of populations.Policy change is a political reality that is impossible to grasp without paying close attention to human agency17 Policy entrepreneurs’ “social skills”18 are essential to the successful promotion of particular policy solutions within a given “policy window.” Timing is crucial; policy entrepreneurs must be ready to seize the opportunity to promote their preferred policy solution while the “policy window” remains open. For example, when President Obama took office in early 2009, he decided to immediately push for healthcare reform while the Democratic Party controlled both chambers of Congress.19In fact, according to Kingdon, policy entrepreneurs must take advantage of the short “policy windows” that open in the context of a crisis or a major electoral and political realignment to promote particular solutions to address the policy problems of the day.26 they are still underutilized in population health. The empirical evidence population health research generates can benefit significantly from the incorporation of policy entrepreneurs into population health frameworks/models to increase the probability of evidence-informed policy change.With respect to health policies, although policy entrepreneurs have mobilized to address specific issues  in multiple countries ,30 Policy ideas can take different forms, the most important of which are problem definitions and policy solutions.31As Kingdon suggests, policy change is directly impacted by the concrete ideas policy entrepreneurs use to create the political coalitions necessary to bring about change in the context of short “policy windows.”32 More importantly, something must be considered as a collective problem rather than a purely individual matter32 for it to make it onto the policy agenda.33 For instance, drinking and driving only became perceived as a collective problem worthy of government intervention when policy entrepreneurs mobilized to depict drinking and driving as a social problem rather than a purely individual and moral issue.35 This example also illustrates the role of framing in policy change.36 This is the case because policy entrepreneurs frame the issues in certain ways to justify public intervention.37First, the ways in which policy problems are defined is crucial for policy change since certain problem definitions are more likely to draw the attention of the public and policy-makers.38 Here, particular ideas such as “solidarity” or “sustainability” can serve as “coalition magnets” that help actors gather around particular policy problems and solutions.39 The articulation of these problems and solutions is one of policy entrepreneurs’ major tasks. Policy entrepreneurs must strategically frame issues to bring people together and promote both the adoption and the successful implementation of solutions, which requires bringing state bureaucrats on board by convincing them of the “need to reform.”40Second, policy entrepreneurs can build coalitions around particular policy solutions and pressure government officials to adopt these solutions.41 This is why we can supplement Kingdon and his followers’ work on ideas and policy entrepreneurs with a discussion about institutions, which are essential to the comparative analysis of policy change.43 Two types of institutions are particularly important here: decision-making systems and existing policy legacies.While different types of ideas shape policy change, these ideas and the actors who promote them typically exist in a relatively stable institutional environment that creates constraints and opportunities for policy change.43 Second, existing policy legacies create their own constituencies and vested interests, which tend to support the policy status quo.44 At the same time, instead of creating self-reinforcing mechanisms, changing demographic and economic circumstances can generate self-undermining mechanisms that reduce support for them over time as they become increasingly ineffective or expensive.45First, formal political institutions and bureaucratic rules shape political decision-making systems and the role of various policy actors, such as policy entrepreneurs.46 This is why the analysis of policy change should take into account how territorially-embedded institutions can shape opportunities for, and obstacles to, policy change. This means that the analysis of policy change at the sub-national level should adopt a comparative lens to grasp key institutional differences among states, regions, or municipalities. Conversely, when moving to the national level, comparisons should be international since comparing the decision-making systems and policy legacies of different countries helps account for why the same policy ideas are successfully adopted and implemented in some countries but not in others.47In federal or decentralized political systems such as the United States, both decision-making systems and existing policy legacies can vary greatly from one state or even one municipality to the next.51 which makes population health a politically-charged science where hypotheses are developed based on ideas that lean towards collective good, rather than neo-liberal, free market capitalism.52 Although the policy implications of population health are quite clear, population health has largely remained an academic exercise, where frameworks have been developed for examining inequities55 and complex analyses have focused on generating empirical evidence.58At the core of the population health agenda is a philosophy of social justice and equity,60 The mobilization of policy entrepreneurs over population health issues such as urban planning policy could influence decision makers’ perspective on evidence,61 and potentially is a vital missing link in achieving the final goal of effecting policy change based on population health research.Few efforts have been made to leverage this evidence to facilitate policy change, pointing towards an obvious disconnect between generation of empirical evidence and policy formulation and implementation. For example, a significant amount of research has been conducted on the influence of urban planning policy on human health and, although policy initiatives have emerged in response to this research, the rate of translation of evidence into policy does not match the volume of research.However, we identify three main challenges in developing consensus on advancing the concept of policy entrepreneurs in population health:Broad Scope: Population health encompasses a multitude of disciplines and sectors with research ranging from behavioural sciences to social sciences, and from epidemiology to urban design. This scenario creates the need for both overarching advocacy groups, as well as issue specific  leaders to act as policy entrepreneurs.Institutional Barriers: Those attempting to create space for new actors will inadvertently face entrenched institutional and systemic barriers. This means that policy entrepreneurs in population health should work with existing networks of researchers, policy-makers, advocates, activists, and non-governmental organizations. Policy entrepreneurs should work closely with existing stakeholders in population health to promote specific policy solutions.Ethical Implications: It is critical to articulate the roles of policy entrepreneurs and population health researchers in effecting policy change to avoid crossing ethical boundaries, especially if the entrepreneurs and researchers are going to benefit from proposed policy changes. For instance, if active researchers work with specific policy entrepreneurs, declaring conflicts of interest would have to be mandatory.62 to establish stronger links with policy makers through collaborative scholarship.63 Nevertheless, there are limitations to existing knowledge translation approaches in advancing policy change because the theoretical lens in this area focuses exclusively on evidence uptake; rather than view policy change more broadly as a set of ideas driven by competing political forces. As Oliver et al emphasize,64 there is a need to generate empirical evidence on the impact of empirical evidence uptake in policy change mechanisms by studying the interaction between population health research and population health policy implementation.Population health researchers have a role to play in shaping ideas by utilizing existing tools of knowledge translation65 Moreover, if policy entrepreneurs working with researchers are involved as key stakeholders on the path from research to policy change in population health, we think that the probability of shaping ideas based on empirical evidence will increase, as these entrepreneurs can successfully articulate policy problems and provide appropriate policy solutions.We suggest that the next major effort in moving the population health approach forward would be to develop frameworks for engaging with the politics of policy making. Also, it is time to move beyond knowledge translation to develop ideas that maximize effective use, and minimize misuse, of empirical evidence.47 propagating ideas that could cause policy change should take into account territorially-embedded institutions. Whether it is comprehending institutional differences at the sub-national level  or understanding the role of varying decision-making systems in effecting similar policy ideas in different countries,48 cross-jurisdictional scans, comparative analyses, and public policy evaluations would be effective tools.68 For example, the imminent legalization of marijuana in Canada across 13 provincial and territorial jurisdictions is bound to raise challenges regarding implementation and regulation.70 This policy change would benefit from cross-jurisdictional scans and comparative analyses that would aid policy entrepreneurs in influencing institutions across jurisdictions.Because both policy change and the mobilization of policy entrepreneurs across jurisdictions are dependent on varying decision-making systems and existing policy legacies,Through our critical analysis of relevant literature, especially the work of Kingdon and the concept of policy entrepreneurs, we extend systematic recommendations to advance a burgeoning discussion in adopting new approaches to successfully implement evidence-informed population health policies. Yet the fact that our contribution focuses primarily on Kingdon’s work and the concept of policy entrepreneurs is a clear limitation. More work is needed to engage with, and draw on, other aspects of the rich literature on policy change.The authors thank Patrik Fafard, Rachel Hatcher, and the anonymous reviewers for their comments and suggestions. Daniel Béland acknowledges support from the Canada Research Chairs Program.Not applicable.Authors declare that they have no competing interests.The article was co-conceptualized and written by both authors through an iterative process.1Johnson Shoyama Graduate School of Public Policy, University of Saskatchewan, Saskatoon, SK, Canada. 2Johnson Shoyama Graduate School of Public Policy, University of Regina, Regina, SK, Canada.


Recent years have seen an explosion of multidisciplinary interest in ancient human warfare. Theory has emphasized a key role for kin-selected cooperation, modulated by sex-specific demography, in explaining intergroup violence. However, conflicts of interest remain a relatively underexplored factor in the evolutionary-ecological study of warfare, with little consideration given to which parties influence the decision to go to war and how their motivations may differ. We develop a mathematical model to investigate the interplay between sex-specific demography and human warfare, showing that: the ecology of warfare drives the evolution of sex-biased dispersal; sex-biased dispersal modulates intrafamily and intragenomic conflicts in relation to warfare; intragenomic conflict drives parent-of-origin-specific patterns of gene expression—i.e. ‘genomic imprinting’—in relation to warfare phenotypes; and an ecological perspective of conflicts at the levels of the gene, individual, and social group yields novel predictions as to pathologies associated with mutations and epimutations at loci underpinning human violence. Discsensu )contra [Our analysis suggests that intense intrafamily conflict may arise in the context of warfare, with parents encouraging reluctant sons to go to war and to show valour in battle , and with fathers being more encouraging and mothers being more circumspect . Such conflicts of interests underline the importance of understanding the cultural transmission of warfare (reviewed in ): in parcontra ,73), butWe have also shown that sex-specific demography can generate intragenomic conflict over warfare. Specifically, female-biased dispersal can result in a young male being more related to his groupmates via his father than via his mother, such that his paternal-origin genes are relatively more favoured to induce belligerence and bravery behaviours than are his maternal-origin genes. We predict that this intragenomic conflict will result in genomic imprinting: loci that promote belligerence and/or bravery behaviours are expected to be maternally silenced and paternally expressed, while loci that inhibit these behaviours are expected to be paternally silenced and maternally expressed . AlthougA remarkable feature of the kinship theory of genomic imprinting is that it not only illuminates adaptation but also yields testable predictions as to the particular maladaptive phenotypes associated with deleterious genetic and epigenetic mutations ,62,75–77


Neocytolysis is the selective destruction of those erythrocytes that had been formed during stress-erythropoiesis in hypoxia in order to increase the oxygen transport capacity of blood. Neocytolysis likely aims at decreasing this excess amount of erythrocytes and hemoglobin (Hb) when it is not required anymore and to decrease blood viscosity. Neocytolysis seems to occur upon descent from high altitude. Similar processes seem to occur in microgravity, and are also discussed to mediate the replacement of erythrocytes containing fetal hemoglobin (HbF) with those having adult hemoglobin (HbA) after birth. This review will focus on hypoxia at high altitude. Hemoglobin concentration and total hemoglobin in blood increase by 20–50% depending on the altitude  and the duration of the sojourn. Upon return to normoxia hemoglobin concentration, hematocrit, and reticulocyte counts decrease faster than expected from inhibition of stress-erythropoiesis and normal erythrocyte destruction rates. In parallel, an increase in haptoglobin, bilirubin, and ferritin is observed, which serve as indirect markers of hemolysis and hemoglobin-breakdown. At the same time markers of progressing erythrocyte senescence appear even on reticulocytes. Unexpectedly, reticulocytes from hypoxic mice show decreased levels of the hypoxia-inducible factor HIF-1α and decreased activity of the BCL2/adenovirus E1B 19 kDa protein-interacting protein 3 (BNIP3), which results in elevated mitochondrial activity in these cells. Furthermore, hypoxia increases the expression of miR-21, which inhibits the expression of catalase and thus decreases one of the most important mechanisms protecting against oxygen free radicals in erythrocytes. This unleashes a series of events which likely explain neocytolysis, because upon re-oxygenation systemic and mitochondrial oxygen radical formation increases and causes the selective destruction of those erythrocytes having impaired anti-oxidant capacity. Adjusting amount and function of erythrocytes is required in a variety of situations, the most obvious being the decrease in Hb after birth and the slow replacement of erythrocytes containing HbF with ones with HbA after birth  at moderate altitudes  but much more pronounced at higher altitudes  because of the sigmoidal shape of the oxygen dissociation curve  varies during a sojourn at high altitude  reaching even pre-altitude values  Haase,  and adjuThe rapid increase in reticulocyte count, which is commonly observed, is likely caused by increased bone marrow blood flow and immature release of red cells . Most experimental evidence comes from work on mice, whereas evidence for human equivalents is sparse. It has to be noted that the mouse model most often used is phenylhydrazine-induced lipid-peroxydation and hemolytic anemia , with much enhanced maturation  back to normal  upon travel to sea level and found a decrease by 9% in erythrocyte mass within 3–7 days after descent, a rapid decrease in EPO, and increased bilirubin. Changes did not occur in three subjects receiving EPO upon descent   redox couples and reduced membrane thiols (Rogers et al., Interestingly, it was found that treating mice with polyethylene glycol-conjugated catalase, which is not taken up by reticulocytes and mature erythrocytes, as well as treatment with the anti-oxidant N-acety-cysteine increased reticulocyte half-life and prevented the reduction in hematocrit (Song et al., 6 erythrocytes per minute in humans.The average life-span of mature erythrocytes is 100–130 days. The destruction rate amounts to approximately 1% per day. Senescent erythrocytes are removed by the reticulo-endothelial system, mainly in the spleen, where cells are tested for functionality and are sequestered “if they don't pass the test” Rifkind, . Random 59Fe disappearance rate from blood in Peruvian high altitude relative to sea-level residents (Huff et al., Interestingly, erythrocytes produced in hypoxic stress appear to have a shortened life span in some species, which is caused by increased random hemolysis and accelerated senescence (Fryers and Berlin, If in fact erythrocytes produced by hypoxic marrow have characteristics limiting their survival upon return to normoxia, then hemolysis will affect different age-cohorts of erythrocytes depending on the duration of the sojourn and on the altitude (Rasmussen et al., The situation is different for long-term sojourners and high altitude residents returning to low altitudes, because all their erythrocytes in circulation may have a decreased anti-oxidant capacity. Thus, elevated ROS will not only lyze young erythrocytes, but also random destruction might be increased and shorten erythrocyte life span. Hemolysis will progress until all erythrocytes with high altitude characteristics will be replaced by normoxic ones having increased antioxidant capacity. This process might cause a severe hemolytic strain, which might be even more pronounced in polycythemic individuals with chronic mountain sickness.There are indications of destruction of erythrocytes formed during exposure to hypoxia upon return to normoxia. Mechanisms are unclear and might include withdrawal of EPO and impaired defense against increased ROS. Experiments are needed to better define the mechanisms causing the fast and selective removal of neocytes formed in situations of stress erythropoiesis and to clearly distinguish between selective destruction and random loss.Another aspect to be clarified concerns the use of the term “neocytolysis,” which implies the destruction selectively of erythrocytes formed in an acute and transient situation of stress erythropoiesis. Thus this term cannot be used to describe the destruction of a fraction of erythrocytes produced during long-term or even life-long exposure to such a stress environment such as fetal life and being an altitude native. In those situations it needs to be sorted out whether just erythrocytes newly released from the marrow are removed, or whether all circulating cells are more susceptible to random loss, and why.The author confirms being the sole contributor of this work and approved it for publication.The author declares that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. The reviewer IB and handling Editor declared their shared affiliation.


It remains unclear whether the lack of clinical trial success and drug approval for cognitive impairment associated with schizophrenia (CIAS) is due to compounds being ineffective, or whether trial methodology itself has been a limiting factor in successfully demonstrating the efficacy of these agents. Schizophrenia is a heterogeneous disorder and whilst cognitive deficits are a core feature, the profile and degree of neuropsychological impairment can vary across patients. Though most individuals with schizophrenia exhibit some general cognitive impairment compared to antecedent expectations, such as premorbid intelligence, up to a quarter display cognitive performance in the ‘normal’ range. This may pose a problem for pro-cognitive drug trials in this population given that it potentially inflates baseline scores and reduces the scope to see improvement between treatment and placebo groups. In order to examine this potential issue, we investigated participant-level trajectories of cognitive performance among patients with schizophrenia enrolled in a multi-national, phase II clinical trial.We conducted a post-hoc analysis of existing trial data from 463 patients with schizophrenia who participated in a randomized, double-blind, placebo-controlled trial. Patients met established diagnosis for schizophrenia (DSM-5), were clinically stable (non-acute) and had no more than moderate severity ratings on the Positive and Negative Syndrome Scale (PANSS). During the trial, participants completed two different neurocognitive test batteries, the Cambridge Neuropsychological Test Automated Battery (CANTAB) and the MATRICS Consensus Cognitive Battery (MCCB), at 4 separate time points . Participant data were pooled across placebo and treatment groups to explore trajectories of cognitive performance, at the participant-level, across the course of the study.Linear mixed model analyses revealed that participants who performed within the ‘normal range’ at screening on cognitive tasks as measured by CANTAB, continued to perform well at baseline, week 6 and week 12, showing no significant change in their performance. By contrast, participants who performed below the normal range at screening, showed a significant improvement in their test performance across the remainder of the study. When compared in the context of MCCB, those participants who performed a standard deviation (SD) above the MCCB normative mean at screening, were also the participants who performed within the normal range on CANTAB. Approximately 25% of the overall sample were performing within a clinically normal cognitive range at screening.Substantial variability was evident in cognitive performance among the current sample of patients with schizophrenia. We identified a subsample of patients whose performance fell within a clinically normal range. Cognitive improvement was observed only in those who exhibited a deficit at screening, bringing into question whether the inclusion of unimpaired patients in clinical trials increases the risk of ceiling effects and minimizes chance to see change. Further analyses will determine the interaction between different cognitive trajectories and the treatment arms included in this trial to explore whether there are individuals with a particular cognitive profile who are most likely to respond to treatment. This has potentially important methodological implications in the search to find a drug to treat CIAS.


Fetal brain development is known to be affected by adverse environmental exposures during pregnancy, including infection, inflammation, hypoxia, alcohol, starvation, and toxins. These exposures are thought to alter autophagy activity in the fetal brain, leading to adverse perinatal outcomes, such as cognitive and sensorimotor deficits. This review introduces the physiologic autophagy pathways in the fetal brain. Next, methods to detect and monitor fetal brain autophagy activity are outlined. An additional discussion explores possible mechanisms by which environmental exposures during pregnancy alter fetal brain autophagy activity. In the final section, a correlation of fetal autophagy activity with the observed postnatal phenotype is attempted. Our main purpose is to provide the current understanding or a lack thereof mechanisms on autophagy, underlying the fetal brain injury exposed to environmental insults. Autophagy is the cellular “self-eating” process by which damaged intracellular proteins, organelles and pathogens are degraded , GFP (green fluorescence protein), and LC3 into a single RFP-GFP-LC3B tag . The fluorescence of the tag can be exploited to expose acidic compartments, such as those found in lysosomes. While the green GFP LC3-II and red RFP fluorescence tags together shine yellow and are both present in the neutral pH of the autophagosome, the green GFP LC3-II signal is quenched in the acidic environment of the lysosome, leaving the pH-stable mRFP-LC3 signal to fluoresce red alone  is insufficient to deal with the biological variability and heterogeneity of an organ/tissue, which requires specialized expertise. Fluorescent microscope or flow cytometry has the potential experimental pitfalls, such as potential for subjectivity, uniform, and criteria for quantitation. Immunoblotting could be less sensitive and informative when analyzing tissue- or stage-specific variations. As autophagy involves dynamic and complicated processes, it is very important to carry out proper assays that deal with the nature of autophagy. All tests that are listed in the Table Multiple different environmental exposures alter autophagy activity in the fetal brain Table . BroadlyMultiple infectious agents alter autophagy as part of their pathogenic exertion. The Zika virus (ZIKV) may cross the placental barrier via a special type of autophagy called secretory autophagy  phenotype. It has been shown that infecting fetal astrocytes with an adenovirus based vector of the Nef protein leads to accumulation of autophagosomes by way of blocking their fusion with lysosomes. As autophagy has an essential role in innate immunity, the manufacture of Nef by HIV safeguards its presence inside the cell and allows it to avoid destruction by the lysosome's enzymatic and acidic environment  is controversial. The findings in several rodent studies have demonstrated conflicting roles for autophagy, with some data suggesting a cell-protective role . Consequently, chronic ethanol exposure may impair protective autophagy function when fetal neurons are faced with increased stress.A second toxin associated with recreational drug use is 3,4-methylenedioxymethamphetamine (MDMA). It is also used to treat post traumatic stress disorder (PTSD)  acts as a non-competitive antagonist of the glutamatergic N-methyl-d-aspartate (NMDA) receptor. Its administration to pregnant rats alters the behavior of their offspring and causes neurodegenerative effects similar to those seen in schizophrenia (SCH) (Radonjić et al., While some maternal exposures are part of the spectrum of substance abuse, others are so ubiquitous that they are difficult to avoid. For example, paraquat is a commonly used herbicide. Paraquat exposure to a human progenitor cell line is associated with an increase in autophagy (Zhao et al., A final category of substances that alter autophagy brain activity in cells is very small metal particles. Metals, due to their nature, cannot be degraded by a lysosome's enzymatic complement. Consequently, the entry of micronized metals into a cell may induce autophagy though the digestive process cannot be completed. Instead, the particles accumulate in autophagosomes. Researchers have raised concerns about the impact the fetal and neonatal brain may suffer from altered autophagy activity from exposure to silver (Guo et al., The previous discussions on various exposures are not exhaustive and we cannot explain the mechanism for all the exposures and phenotypes listed in Table in-vitro. Future research is urgently needed to employ these markers for in utero identification of potential disease processes associated with environmental exposures in pregnancy.All markers of autophagy activity cited in Table in vivo modulators of autophagy would offer additional tools to reverse common pathogenic affecters of autophagy.While many environmental exposures that influence autophagy activity have been identified, many remain to be discovered. The discovery of additional safe and economical Three promising treatments for altered autophagy levels include glucose, modest hypoxia, and hydroxychloroquine.Our recent discovery of glucose infusion for pathogenic autophagy activity represents a potentially accessible and cost-effective treatment of perinatal brain injury in the setting of intrauterine inflammation secondary to chorioamnionitis or preterm birth (Lei et al., A potential treatment for chronic ethanol exposure could lie in the development of safe autophagy inducers. This has already been demonstrated in a limited way by a study which showed that a modest hypoxic preconditioning induced protective autophagy in human neuronal stem cell cultures affected by long term exposure to alcohol Luo, .While the peak of the recent Zika outbreak in the Americas has passed, it is imperative that further research is performed about its management. Attempting to affect its clinical course with the use of autophagy modulating molecules such as hydroxychloroquine or possible acai derivatives offers new areas for research.Finally, further studies are needed in order to elucidate the causal connections between altered embryonic and fetal autophagy activity and psychiatric disorders.IB: Designed review and selected articles for the synopsis, guided manuscript structure, and supervised writing: PC: Reviewed literature and participated in the writing of the manuscript; RV: Reviewed literature and participated in the writing of the manuscript; JL: Helped in article selection for the review, reviewed literature, and participated in the writing of the manuscript.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.


Aminoglycosides are potent antibiotics deployed worldwide despite their known side-effect of sensorineural hearing loss. The main etiology of this sensory deficit is death of inner ear sensory hair cells selectively triggered by aminoglycosides. For decades, research has sought to unravel the molecular events mediating sensory cell demise, emphasizing the roles of reactive oxygen species and their potentials as therapeutic targets. Studies in recent years have revealed candidate transport pathways including the mechanotransducer channel for drug entry into sensory cells. Once inside sensory cells, intracellular targets of aminoglycosides, such as the mitochondrial ribosomes, are beginning to be elucidated. Based on these results, less ototoxic aminoglycoside analogs are being generated and may serve as alternate antimicrobial agents. In this article, we review the latest findings on mechanisms of aminoglycoside entry into hair cells, their intracellular actions and potential therapeutic targets for preventing aminoglycoside ototoxicity. Aminoglycosides are critical antimicrobials with potent activities against gram negative bacteria  glycosidically linked to a glucosaminopyranose (ring I). Substitutions attached at either position 5 or 6 on ring II give rise to different aminoglycoside molecules that are categorized as either 4, 5 or 4, 6 aminoglycosides. To date, over 25 aminoglycoside compounds have been purified or synthesized  and irreversible sensorineural hearing loss (ototoxicity). Nephrotoxicity is largely reversible, whilst hearing loss is permanent. Hearing loss occurs in a dose-dependent manner and the antibacterial efficacy, nephrotoxicity, and ototoxicity of these drugs correlate with aminoglycoside blood concentration  and low calcium , is the major driver for sensory transduction. During sound stimulation, K+ ions flow down an electrochemical gradient into hair cells through mechanically-gated channels located in sensory hair cell bundles. These unique, mechanically sensitive channels are non-selective cation carriers, allowing other large positively charged molecules, like aminoglycosides, to enter the hair cell.In the mammalian cochlea, the apical surface of sensory hair cells are located in an extracellular fluid compartment filled with a unique endolymph solution, comprised of high potassium –a highly specialized capillary network that controls exchanges between blood and the interstitial space in the cochlea. The BLB is one of the first sites of aminoglycoside entry from the blood into the inner ear, a concept first proposed by Hawkins  Dai and. The BLBAminoglycosides conjugated to fluorescent labels have been developed and proven to be a powerful tool in the study of aminoglycoside trafficking from the blood into the endolymph. The most commonly used fluorescent aminoglycoside is gentamicin sulfate conjugated to the Texas red fluorophore, so called Gentamicin Texas Red  prevents aminoglycoside entry into hair cells and confers hair cell protection from various aminoglycosides  channels, which are large calcium-permeant, cationic channels ) and other subcellular levels  may open the door to preventing ototoxicity  decode genetic information and convert it into proteins  in the eukaryotic cell, the mitoribosome was implicated in aminoglycoside ototoxicity in 1993 ; GTP binding protein 3 (GTPBP3); 5-methylaminomethyl-2-thiouridylate methyltransferase (TRMU); and mitochondrial transcription factor 1  and reactive nitrogen species (RNS), and it is the odd number of electron(s) of a free radical that makes it unstable, short-lived and highly reactive  does not increase susceptibility to aminoglycoside induced cell death suggesting alternate roles for ROS . Should less ototoxic aminoglycosides with maintained or better antimicrobial potencies be developed, an accelerated track to clinical translation could be followed.Tremendous genetic and functional work has shed light on the intricacies of aminoglycoside entry and action. This has facilitated the development of strategies with significant translational promise, in particular, the concept of modifying the aminoglycoside itself to prevent ototoxicity. The paradigm of modifying aminoglycoside antibiotics has been around for many years and nearly all antibiotics brought to market over the last 30 year have been variations on existing drugs (The Pew Charitable Trusts, Going forward it is imperative that we continue to develop a better insight and scientific understanding of aminoglycoside entry and action, and that scientists modifying aminoglycosides to different ends continue to work together to develop compounds with better physiochemical properties. Whilst the development of life-saving antibiotics will always remain the priority, we owe it to our patients to continue to explore the possibility that a simple tag or chemical modification could limit the dramatic side effect that is aminoglycoside-related hearing loss—a global health problem.MEO’S, AP, RL, AS, AGC and AJR: literature search; MEO’S, AGC and AJR: figure preparation and manuscript preparation.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.


Systems studies of drought stress in resurrection plants and other xerophytes are rapidly identifying a large number of genes, proteins and metabolites that respond to severe drought stress or desiccation. This has provided insight into drought resistance mechanisms, which allow xerophytes to persist under such extreme environmental conditions. Some of the mechanisms that ensure cellular protection during severe dehydration appear to be unique to desert species, while many other stress signaling pathways are in common with well-studied model and crop species. However, despite the identification of many desiccation inducible genes, there are few “gene-to-field” examples that have led to improved drought tolerance and yield stability derived from resurrection plants, and only few examples have emerged from model species. This has led to many critical reviews on the merit of the experimental approaches and the type of plants used to study drought resistance mechanisms. This article discusses the long-standing arguments between the ecophysiology and molecular biology communities, on how to “drought-proof” future crop varieties. It concludes that a more positive and inclusive dialogue between the different disciplines is needed, to allow us to move forward in a much more constructive way. Four hundred and fifty million years of land plant evolution has generated biological complexity, which has allowed plants to adapt to terrestrial environments, ranging from extreme cold environments in the Arctic and Antarctica, high salinity environments to extreme temperature changes and drought conditions in desert environments . With more than 130 known varieties, resurrection plants are mostly found in arid and semi-arid environments,  in the chloroplasts due to excess light energy. ROS subsequently oxidize proteins and lipids, damage DNA and RNA, and ultimately lead to programmed cell death , and many of the Arabidopsis TFs have been shown to confer stress tolerances in unrelated crop species and vice versa  and non-protein coding RNAs (ncRNAs) (Giarola et al., Interestingly, transcriptome studies of resurrection plants not only found a high proportion of unknown transcripts (33% C. plantagineum to improve drought tolerance in tobacco failed (Iturriaga et al., Zygophyllum xanthoxylum to enhance stress tolerance in alfalfa and Lotus corniculatus (Bao et al., Early attempts to utilize TRGs such as desiccation induced proteins from There also appears to be a lack of synergy between different disciplines with physiology, ecophysiology on the one hand, and genetics and molecular biology on the other. Perhaps the problem is not only the type of plant we study, but also how we study stress tolerance mechanisms in general? Crop physiologists rightly argue that molecular mechanisms of plant survival traits are often studied in isolation to physiological responses, whether this is carried out in model species such as Arabidopsis Blum, , or in eMedicago truncatula and rice (Harb et al., Desiccation tolerance in resurrection plants is a survival trait, and survival traits after any given stress have generally been a popular phenotype for gene discovery and gene function in model species (Woo et al., Rhazya stricta, which is common in arid zones at elevations of 100–700 m above sea level, and overcomes water restriction through long tap roots to access water in underground river beds (Batanouny and Baeshin, In crop plants drought survival through delayed mortality is unlikely to be a suitable option due to expected growth and yield penalties, and therefore questions regarding the usefulness of survival traits in achieving meaningful improvements still remain (Passioura J., Extensive physiological phenotyping under native growth conditions is essential due to the extreme conditions experienced in their native environments. Furthermore, growth conditions in control environments often do not fully reflect the conditions experienced in desert environments, especially with regards to the prevailing light conditions Table , even thR. stricta in its native desert environment revealed that R. stricta maintains growth and high photosynthetic rates at leaf temperatures as high as 43°C, light intensities >1,000 μmol m−1 s−1 and high vapor pressure deficits (VPDs; Lawson et al., RUBISCO ACTIVASE isoforms, that are likely responsible for the maintenance of high Rubisco activities and photosynthetic rates under these extreme conditions (Lawson et al., R. strica is able to maintain an adequate water supply in order to maintain a high and constant photosynthetic activity (Lawson et al., R. stricta may not suffer from drought stress in those circumstances, it nevertheless gives us an insight into extreme thermo- and high light tolerance in arid environments, which are often part of drought stress conditions experienced in the field. Importantly, by combining detailed physiological analysis with genetic investigations, it was possible to identify some potentially different physiological adaptation mechanisms that go beyond the usual TFs and chaperones mentioned above. Interestingly, a detailed study of the diurnal transcriptome analysis of R. stricta, identified considerable overlap with C. plantagineum and P. euphratica such as cysteine proteases and raffinose synthesis genes, highlighting more general protective mechanisms against high temperature (Yates et al., R. stricta, such as photosynthesis and respiration associated genes, were differentially expressed at midday during a diurnal period responding to VPD, temperature and light levels (Yates et al., For example, physiological and transcriptome analysis of With unprecedented access to increasing genome information and transcriptome datasets from a variety of plants, coupled with tools to analyse and compare these datasets, we are beginning to identify gene families and gene regulatory networks behind complex traits such as dehydration tolerance. It is only by developing a more realistic framework in which to study drought resistance mechanism that we will make progress in understanding how plant productivity can be maximized under water limiting conditions. For this to happen, a more positive and inclusive dialogue between the different disciplines, all primarily concerned with “drought-proofing” future crop varieties, is essential in order to move forward in a much more constructive way.The author confirms being the sole contributor of this work and approved it for publication.The author declares that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.


The complex roles of nature and culture in poverty traps call for diverse and often transformative poverty alleviation strategies. The poverty trap concept strongly influences current research and policy on poverty alleviation. Financial or technological inputs intended to “push” the rural poor out of a poverty trap have had many successes but have also failed unexpectedly with serious ecological and social consequences that can reinforce poverty. Resilience thinking can help to (i) understand how these failures emerge from the complex relationships between humans and the ecosystems on which they depend and (ii) navigate diverse poverty alleviation strategies, such as transformative change, that may instead be required. First, we review commonly observed or assumed social-ecological relationships in rural development contexts, focusing on economic, biophysical, and cultural aspects of poverty. Second, we develop a classification of poverty alleviation strategies using insights from resilience research on social-ecological change. Last, we use these advances to develop stylized, multidimensional poverty trap models. The models show that (i) interventions that ignore nature and culture can reinforce poverty (particularly in agrobiodiverse landscapes), (ii) transformative change can instead open new pathways for poverty alleviation, and (iii) asset inputs may be effective in other contexts . Our model-based approach and insights offer a systematic way to review the consequences of the causal mechanisms that characterize poverty traps in different agricultural contexts and identify appropriate strategies for rural development challenges. Governments worldwide recently agreed to “end poverty in all its forms everywhere” by 2030 with minimal impact on Earth’s life-support systems , has gaiBox 1Poverty trap: A situation in which self-reinforcing mechanisms “trap” people in poverty (Attractor: A state (or set of states) of a system toward which nearby states tend over time. In this article, a system state consists of the levels of capitals.Basin of attraction: The set of states of a system, which tend over time toward the same attractor. We use basins of attraction to visually represent the dynamics of models with two or more capitals.Physical capital: A manufactured asset that can increase economic output  ThResilience has become a popular concept in development policy . ReThat poverty can lead to an increased rate of environmental degradation  is an asIn contrast, the conventional high-input agricultural systems often recommended to increase production can also degrade the biophysical systems on which agricultural production depends . MoreoveIn rural landscapes, social-ecological relationships are mediated by land management knowledge and practices  (32). FoThe poverty trap concept was developed to explain the existence of multiple stable states of economic development, particularly the existence of persistent poverty  in sociaRegime shifts are large, abrupt, and persistent shifts across thresholds into different attractors in social-ecological systems . (ii) ChBox 2“S curve” models resulting from Solow growth models are the basis for the poverty trap models popularly in use today  and market liberalization strategies (type II) may lead to unexpected negative consequences in situations where agricultural intensification results in degradation of natural capital, such as in some agrobiodiverse landscapes. That the situation becomes even worse once the role of cultural capital is recognized reflects the practical difficulty of alleviating poverty that persists because of multiple interlocking mechanisms  pathway that improved the renewal rate of natural capital through a change in practice may also work . These pOur model results, that type I or II alleviation pathways may be effective for escaping a subsistence trap, only apply, however, to interventions that are consistent with the assumptions of the subsistence trap model  interactions between other dimensions such as health and education (The poverty trap has proven a useful concept in popularizing efforts to combat persistent poverty across many parts of the developing world. However, one-dimensional conceptualizations of poverty traps encourage a narrow range of alleviation responses. Resilience thinking can progress research and policy on poverty alleviation by helping to understand the complex dynamics of the social-ecological environments in which the rural poor live. Combining resilience thinking concepts with simple models as proposed here allows for systematic navigation among the different alleviation responses, from asset inputs to transformative change, that are required for integrated sustainable development.Here, we summarize the mathematical formulation of the poverty trap models used in We followed the conventional implementation of a savings trap using a Solow growth model (We added a “natural capital” state variable to the conventional poverty trap model . In the In this model , natural


Amyloids are traditionally considered pathological protein aggregates that play causative roles in neurodegenerative disease, diabetes and prionopathies. However, increasing evidence indicates that in many biological systems nonpathological amyloids are formed for functional purposes. In this review, we will specifically describe amyloids that carry out biological roles in sexual reproduction including the processes of gametogenesis, germline specification, sperm maturation and fertilization. Several of these functional amyloids are evolutionarily conserved across several taxa, including human, emphasizing the critical role amyloids perform in reproduction. Evidence will also be presented suggesting that, if altered, some functional amyloids may become pathological. Amyloids are proteins that self-assemble into highly ordered cross-β-sheet rich structures that typically have been viewed as pathological entities associated with neurodegenerative disease and prionopathies. Growing evidence, however, indicates that most proteins can adopt the amyloid fold given the correct environment and that some amyloids carry out nonpathological biological roles and are known as functional amyloids . Indeed,Considering that, once formed, perpetuation of life must also occur, it is not surprising that several of the most fundamental processes in reproduction, including gamete formation and gamete interactions, utilize functional amyloids and that their use has been conserved throughout evolution. In some cases, in spite of a divergence in amino acid sequence of proteins involved in these reproductive processes, their propensity to form amyloid has been maintained allowing conservation of the structure across species. In this review, we will specifically discuss amyloids that perform biological roles in reproduction, properties that may distinguish them from pathological amyloids, and evidence suggesting that under some conditions reproductive functional amyloids may become pathological. The amyloids we will describe herein range from those consisting seemingly of individual proteins functioning in their amyloid state to complex functional amyloid matrices composed of several to many proteins.Sexual reproduction requires the production of haploid germ cells from diploid progenitor cells by the process of meiosis. A number of RNA binding proteins mediate this process, including controlling the translation of cyclins which direct progression through the meiotic divisions . AlthougTranslational control of critical mRNAs is also needed during spermatogenesis in mice and human. Deleted in AZoospermia-like (DAZL), an RNA binding protein that mediates translation in mice and which is essential for gametogenesis, and the related human meiosis-specific DAZ1-DAZ4 proteins, which have predicted prion-like domains, are proposed to function much like Rim4 in yeast ,10,11. AXenopus laevis revealed that Xvelo, a disordered protein with a predicted prion-like domain, is a major component of Balbiani bodies and its assembly into an amyloid matrix via its prion-like domain forms the Balbiani body structure . Pr. Pr24]. We also demonstrated that the sperm AM is stable at pH 3 but rapidly disassembles at pH 7. The pH-dependent dispersion of the AM correlates with a change in amyloid structure leading to a loss of mature forms (OC antibody reactive) and a gain of immature amyloid forms (A11 antibody reactive) . This suThe significance of the AM as an amyloid is not known. It is possible that the AM amyloid is important for the sequential release of proteins during the acrosome reaction and/or for proper orientation of signaling complexes that function during fertilization. Spermatozoa from mice lacking the cystatin CRES, an amyloidogenic protein in the AM core, are unable to undergo the acrosome reaction, show reduced protein tyrosine phosphorylation, and exhibit fertility defects in vitro . HoweverIt is also possible that the AM amyloid functions as a defined three-dimensional structure that interacts with the ZP during gamete recognition. Indeed, the model of a single sperm protein functioning as a ligand for the sperm receptor on the oocyte has been replaced by the notion that sperm-ZP binding likely involves a multitude of sperm fertilization molecules . We woulThe ZP is an extracellular fibrillar matrix that surrounds the oocyte and plays critical roles mediating species-specific gamete recognition and protection from polyspermy. The mouse ZP is formed by three proteins ZP1, ZP2, and ZP3, all of which have a ZP polymerization domain, further divided into N-terminal (ZP-N) and C-terminal (ZP-C) subdomains, that directs fibril formation and assembly into the three-dimensional ZP matrix ,31 FiguA. Each ZThe first indication that the egg coat is an amyloid was in fish and silkmoth oocytes, where it was suggested that the highly stable amyloid structure protected the oocyte under stress conditions ,39,40. OThe significance of the ZP/egg coat as an amyloid may be several-fold. As proposed in the fish and silkmoth, the inherent stability of the ZP amyloid would provide protection for the oocyte, especially when surrounded by proteases and other hydrolytic enzymes released from spermatozoa. Since ZP structure is important for later processes in early embryogenesis, amyloids may ensure that the structure remains intact after sperm penetration . We specAfter spermatogenesis, spermatozoa are transported through a long, convoluted tubule known as the epididymis. During epididymal transit, spermatozoa undergo a maturation process and acquire the functions of progressive motility and the ability to fertilize an oocyte. Given that sperm are synthetically inactive, maturation requires the interaction of sperm with proteins secreted into the lumen, in a highly region-dependent manner, by the surrounding epididymal epithelium. In addition to facilitating their maturation, the epididymis must also protect spermatozoa from pathogens including those that ascend into the male tract. However, the mechanisms by which these processes occur are not clear.We determined that the normal mouse epididymal lumen contains an extracellular matrix with amyloid properties that surrounds the maturing sperm and which may play roles in sperm maturation and protection . The strWe established that multiple members of the cystatin family 2 of cysteine protease inhibitors contribute to the formation of the luminal amyloid matrix ,54. CRESMice lacking the CRES gene show a profound downregulation of other CRES family members, suggesting interrelated functions . PhenotyWe hypothesize that interactions between CRES family members and cystatin C are integral for luminal amyloid matrix formation and function, not unlike interactions between bacterial curli family members during the formation of bacterial biofilms . In a brDuring ejaculation, spermatozoa are released in seminal fluid, a combination of fluids originating from the epididymis, prostate and seminal vesicles. Studies by Mϋnch et al. showed that human semen contains amyloid fibrils with the ability to enhance human immunodeficiency virus (HIV) infection in vitro . SpecifiProteins that form functional amyloids follow similar aggregation pathways as those that form pathological amyloids, including the development of intermediate oligomeric amyloids which are considered to be the cytotoxic species . One posOur results examining the kinetics of CRES family amyloidogenesis are consistent with other proteins that form functional amyloids by showing rapid rates of amyloid formation in vitro. Immediately following dilution from 6M guanidine-HCl into nondenaturing buffer, all CRES family members form amyloids with slightly different structural and aggregation properties . ThT plaOther reproductive functional amyloids also exhibit fast rates of amyloid formation including Xvelo, the amyloid component of Balbiani bodies, which transitioned into a fibrillar matrix after 12–24 h . SimilarAlthough the structures of functional and pathological amyloid fibrils and matrices appear similar when observed by electron microscopy and atomic force microscopy, it is possible there are differences at the atomic level. For this reason, solid-state nuclear magnetic resonance (SSNMR) has become the gold standard for studying amyloids atomistically. SSNMR can resolve subtle structural differences between different amyloids and this information can be leveraged to identify structural divergence between pathological and functional amyloids.To date, only a few functional amyloids have been examined by SSNMR and of these several were from nonmammalian species or were only of specific protein domains ,75. The Of the few functional amyloids identified to date in the reproductive tract, there appears to be several types: (1) individual proteins that utilize prion-like domains for their self-assembly into an amyloid resulting in altered protein function; and (2) proteins that do not possess classic Q/N-rich prion-like domains, but instead contain multiple short amino acid stretches with amyloidogenic propensity and which assemble with several to many other proteins (related family members or unrelated proteins) into complex amyloid matrices with biological functions. We propose that those in the former category might be like yeast prions which often are DNA/RNA binding proteins that use the amyloid fold to mediate protein function, but which also have the potential to elicit profound changes in phenotype and even the inheritance of new traits . Those iThe commonalities between functional and pathological amyloids prompts the question of whether some disease-associated amyloids may in fact represent functional amyloids that have gone awry. Our studies of a mouse model for the human disease cystatin C cerebral amyloid angiopathy-Icelandic type suggests that in some cases this may be so. Although wildtype cystatin C is amyloidogenic, a single point mutation in the human cystatin C gene (L68Q) results in a highly unstable and aggregation-prone protein that readily forms amyloid in cerebral arteries of affected individuals, causing an early death . TransgeTogether these studies suggest that, under some conditions, functional amyloids can become pathological. This may be due to a change in the equilibrium between monomeric and amyloid forms or quality control mechanisms that have become overwhelmed. Given our studies suggesting that some functional amyloids are formed by interactions between several amyloidogenic proteins, it is also feasible that a loss or alteration in one amyloidogenic protein may result in an abnormal accumulation of its partner(s), which as an orphan amyloid may cause pathologies. Alternatively, as suggested by our studies of the L68Q mice, an alteration in a component of a complex functional amyloid could change its overall structure resulting in cytotoxic properties.As presented herein, functional amyloids play important roles in several reproductive processes including gametogenesis and fertilization. Some functional amyloids are evolutionarily conserved emphasizing the critical role amyloids play in reproduction and that nature favors the amyloid fold for these processes. Further study of reproductive functional amyloids, including their formation and disassembly, will not only provide a better understanding of basic mechanisms of reproduction, but knowledge that could be used to develop new therapies for diseases caused by pathological amyloids.