The construction of “smart” materials able to perform specific functions at the molecular scale through the application of various stimuli is highly attractive but still challenging. The most recent applications indicate that the outstanding flexibility of self-assembled architectures can be employed as a powerful tool for the development of innovative molecular devices, functional surfaces and smart nanomaterials. Structural flexibility of these materials is known to be conferred by weak intermolecular forces involved in self-assembly strategies. However, some fundamental mechanisms responsible for conformational lability remain unexplored. Furthermore, the role played by stronger bonds, such as coordination, ionic and covalent bonding, is sometimes neglected while they can be employed readily to produce mechanically robust but also chemically reversible structures. In this review, recent applications of structural flexibility and molecular motions in self-assembled nanostructures are discussed. Special focus is given to advanced materials exhibiting significant performance changes after an external stimulus is applied, such as light exposure, pH variation, heat treatment or electromagnetic field. The crucial role played by strong intra- and weak intermolecular interactions on structural lability and responsiveness is highlighted. Molecular self-assembly (MSA) offers a molecular-level control of material structure, composition, morphology and dimensions, thus enabling the construction of an extensive variety of 1-, 2- and 3-D nanostructures . AstonisBesides these powerful “passive” applications, dynamic and environment-sensitive properties of self-assembled architectures are continuously gaining interest. Non-covalent physical interactions that drive the assembly of building blocks can be readily dissociated and re-associated, thus conferring outstanding flexibility to the final supramolecular structure. Recent advances indicate that taking advantage of the specificity, geometry, strength and sometimes, the reversibility of these interactions enables the elaboration of highly functional and stimuli-sensitive materials. More interestingly, stronger chemical interactions, which are often referred to as irreversible bonds, can also exhibit a certain degree of lability under specific conditions thus allowing the formation of both robust and dynamic materials. Molecular motions and bond lability are therefore now regarded as powerful tools for the construction of “active” materials. However, a better understanding of mechanisms inducing flexibility is required to enlarge potential applications in a near future.In the present review, we aim to compile recent advances in the use of molecular motions to functionalize self-assembled nanostructures. Dynamic properties are discussed according to material nature, structure and bond flexibility. Relevant examples are summarized and classified into three categories of widely investigated self-assembled materials: (i) fully organic; (ii) organic-inorganic hybrid; (iii) metal-organic structures. Special emphasis is given to the crucial role played by strong and weak bonding on structural flexibility and responsiveness of the final product.Non-covalent intermolecular bonds are known to govern self-assembly of molecules through a balance of attractive and repulsive interactions leading to the formation of larger and ordered supramolecules. Understanding the fundamental principles responsible for molecular self-assembly is still challenging due to numerous, complex and specific interplays between multiple subunits or building blocks. In order to engineer dynamic or reconfigurable systems, the key role of some weak non-covalent bonds involved in self-assembly processes have received continued attentions and is now well-documented –15. SuchWeak interactions, such as van der Waals forces, hydrogen bonds and π interactions are among the most prevalent low-energy forces encountered in self-assembled systems. Their weakness and reversibility play a crucial role in the self-assembly process of single or multiple types of building blocks. Generation of ordered structures through these interactions requires the building blocks to move and adjust their initial position even after aggregation. This adjustability is necessary for the final system to reach its lowest-energy state and achieve a nearly perfect organized structure. Essentially, weak bonds holding components in a self-assembled structure are the reasons for structural flexibility .−1 making their dissociation plausible and easy. Despite their trivial strength, such ever-present forces have a significant influence on the ordering and cohesion of alkyl chains within self-assembled monolayers . Due to the robustness of the metal clusters and flexibility in binding orientations from the organic bases, distances between the metal clusters at neighboring planes can be changed by simply crumbling or stretching the organic bases without breaking. Typically, the as-synthesized solids can accept solvents with a noticeable and continuous increase in unit cell volume, and when the solvent is taken out, the frameworks shrunk back to the original volume. When this breathing behavior happens in pillared-layered MOFs, such as MOROF-1 n n .2NDC2DPNI·DMF is exposed to 1-hexanol, chloroform, or nitrobenzene, three new structures are formed  [In addition to the breathing behavior, where the same guest-molecule diffuses into or out of the MOFs, dynamic nature of MOFs is also frequently demonstrated by removal of physically imbedded solvents, followed by a refill with new molecules ,199. Thictively) . In eachctively) .Both two kinds of movements illustrated above involve exchange with small guest molecules. In fact, movements in an ordered structure can also be performed with an applied field or stimulus, including thermal  and presThe use of molecular motions offers a promising strategy for the elaboration of self-assembled structures with unprecedented dynamic properties. The outstanding flexibility of weak physical and strong chemical bonds is increasingly employed to develop novel “smart” materials able to perform specific tasks at the molecular level through the application of one or several stimuli.Remarkably, this strategy can be applied to an extensive variety of material structures, compositions and dimensions. Moreover, as illustrated in this review, numerous properties such as wettability, magnetism, shape, crystalline structure, mechanical robustness and thermal stability, can be easily tuned without substantial effort. This versatility is opening up a wide range of potential applications in multidisciplinary domains including medicine, electronics, sensors, textiles, protective coatings and nanomachinery.Advances in chemistry are however needed to continue the development of such functional materials. By designing new attractive and responsive building blocks that can be self-assembled, molecular chemistry can continuously broaden the number of available functionalities and their efficiency. However, some intrinsic limitations are still to be overcome in order to gain accurate control of structural modifications and increase material performances.It is hoped that gaining comprehension of the highly complex interplays existing between building blocks will encourage the development of novel advanced self-assembled materials with the ultimate goal of constructing systems able to accurately mimic dynamic functions of macroscopic machines or even humans.


Salmonella enterica causes substantial morbidity and mortality in humans and animals. Infection and intestinal colonization by S. enterica require virulence factors that mediate bacterial binding and invasion of enterocytes and innate immune cells. Some S. enterica colonization factors and their alleles are host restricted, suggesting a potential role in regulation of host specificity. Recent data also suggest that colonization factors promote horizontal gene transfer of antimicrobial resistance genes by increasing the local density of Salmonella in colonized intestines. Although a profusion of genes are involved in Salmonella pathogenesis, the relative importance of their allelic variation has only been studied intensely in the type 1 fimbrial adhesin FimH. Although other Salmonella virulence factors demonstrate allelic variation, their association with specific metadata  remains to be interrogated. To date, genome-wide association studies (GWAS) in bacteriology have been limited by the paucity of relevant metadata. In addition, due to the many variables amid metadata categories, a very large number of strains must be assessed to attain statistically significant results. However, targeted approaches in which genes of interest  are specifically sequenced alleviates the time-consuming and costly statistical GWAS analysis and increases statistical power, as larger numbers of strains can be screened for non-synonymous single nucleotide polymorphisms (SNPs) that are associated with available metadata. Congruence of specific allelic variants with specific metadata from strains that have a relevant clinical and epidemiological history will help to prioritize functional wet-lab and animal studies aimed at determining cause-effect relationships. Such an approach should be applicable to other pathogens that are being collected in well-curated repositories. Salmonella enterica infections result in substantial morbidity and mortality worldwide, both in humans and livestock  has “upgraded” to the bowels of some warm-blooded animals, the optimal environment for bacterial multiplication and transmission. Moreover, the maintained ability of S. enterica to “camp” outside of the host in less opulent telluric biotopes further improves its chances of transmission.With the latest official publications on serological grouping of  to 2625 . Two speSalmonella serovar variants with distinct host range are well documented in host species-specific endemic or epidemic strains , as well as recombination, mutations and gene loss  remain poorly defined. Thus, the observed lack of diversity within a serovar might be partially biased by the collection of strains studied.Current serovars . A recenserovars . IncremeSalmonella to colonize and/or cause diseases in different hosts depends not only on the presence of a collection of specific genes, but also on the allelic variation within these genes. In surprising contrast to research in both cancer and metabolic and inheritable diseases, where mammalian single nucleotide polymorphisms (SNPs) are dissected in great detail to determine potential causality  relies on sets of molecules that allow it to bypass natural host defense mechanisms, such as gastric acidity and gastrointestinal proteases and defensins, as well as the aggressins of the intestinal microbiome. In addition, Salmonella utilizes surface molecules, organelles, and machineries, such as adhesins, flagella, and type 3 secretion systems (T3SS) to actively make contact with host cells and deliver molecules that initially improves host colonization, and later its transmission to new hosts. As such, allelic variation in any of these molecules could influence host specificity and pathogenicity.The ability of Salmonella toward the surface of intestinal epithelium by promoting bacterial movement across the mucus layer . Flagella’s near-surface swimming properties optimize the encounter of bacterial adhesins with host receptors . While flagellar motility is clearly required for intestinal colonization , phagocytic cells , or gallbladder and biliary calculi  and anchored on the bacterial surface  encoded T3SS, which then injects effector proteins into enterocytes . Once inside the Salmonella-containing vacuole (SCV), Salmonella deploys a second T3SS encoded by SPI-2 to inject effector proteins that optimize conditions for bacterial survival and replication , a T3S-regulated process . SPI-2 effectors also interfere with MHC-presentation and activation of an immune response that would eliminate Salmonella. If not contained, the bacteria that escape the lymph nodes promote a primary bacteremia that seeds the liver , to initiate a circular reinfection process by taking the biliary route to return to the intestinal lumen. In addition to making biofilms on gallbladder stones, Salmonella adheres to and invades gallbladder epithelial cells  in a SPI-1-dependent manner  variants that harbor an integrin-binding motif  mediate astritis  and OmpAn cancer . Finallyse model . Similarfections .Salmonella strains. This trove of new information has allowed extensive studies on the adaptive history of pathogens. In addition to information on gene acquisition, inactivation, or loss, comparative genomics highlights non-synonymous mutations that may alter function. Unfortunately, the number of mutations is usually too high to make firm conclusions. In contrast, genome-wide association studies (GWAS) that focus on Salmonella strains for which there is host and clinical information would help to better limit the number of genes likely involved in strain-specific phenotypes. Currently, GWAS are mainly used to identify disease-associated sequences within human genomes. Specifically, whole genomes of healthy and affected individuals are sequenced and compared for intra- and inter-genic SNPs that are associated with a specific disease to suggest a potential cause and effect relationship. Discovered associations are expected to support the development of new diagnostic, therapeutic, and preventive tools. Some studies focus on genomic regions already suspected to contribute to disease progression to identify a limited number of associated SNPs. Notably, GWAS have successfully identified several disease-specific SNPs  in at least one host species. Several technologies for targeted sequencing have been developed in recent years, and are based on DNA enrichment methods such as capture by hybridization or microfluidic PCR  Salmonella  and plasmids  result in a local inflammatory response that can profit HGT events  that leads to intestinal persistence , likely creates optimal conditions and timespans for HGT events , thereby increasing the antibiotic resistance gene pool . Consistent with this notion, specific colonization of the ileum can increase the rate of intra-intestinal conjugation  permitting analysis of more strains at the same cost, (2) improving statistical power, and (3) simplifying the bioinformatics and statistical analysis. This latter approach best suits pathogens for which there are already long lists of predicted or known proteins that act as virulence factors lmonella . Studieslmonella , or idenprofiles  stronglyirulence . Finallynfection .To summarize, the identification of biological consequences for allelic variants have reached the critical threshold required to stimulate more systematic investigations on well-curated strain collections, which can now exploit recently developed tools and technologies, such as GWAS and targeted sequencing.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.


Oryza sativa L.) is cultivated in more than 100 countries and supports nearly half of the world’s population. Developing efficient methods to control rice viruses is thus an urgent necessity because viruses cause serious losses in rice yield. Most rice viruses are transmitted by insect vectors, notably planthoppers and leafhoppers. Viruliferous insect vectors can disperse their viruses over relatively long distances, and eradication of the viruses is very difficult once they become widespread. Exploitation of natural genetic sources of resistance is one of the most effective approaches to protect crops from virus infection; however, only a few naturally occurring rice genes confer resistance against rice viruses. Many investigators are using genetic engineering of rice plants as a potential strategy to control viral diseases. Using viral genes to confer pathogen-derived resistance against crops is a well-established procedure, and the expression of various viral gene products has proved to be effective in preventing or reducing infection by various plant viruses since the 1990s. RNA interference (RNAi), also known as RNA silencing, is one of the most efficient methods to confer resistance against plant viruses on their respective crops. In this article, we review the recent progress, mainly conducted by our research group, in transgenic strategies to confer resistance against tenuiviruses and reoviruses in rice plants. Our findings also illustrate that not all RNAi constructs against viral RNAs are equally effective in preventing virus infection and that it is important to identify the viral “Achilles’ heel” gene to target for RNAi attack when engineering plants.Rice ( Oryza sativa L.), one of the most important grain crops, is grown worldwide, with more than 90% (650 million tons) in Asia, where it is consumed directly to supply 36% of the total calories consumed (Rice grassy stunt virus (RGSV) or co-infection by RGSV and Rice ragged stunt virus (RRSV), resulting in the loss of 828,000 tons of rice valued at US$120 million and directly affecting millions of rice farmers (Rice (consumed . Of the  farmers . The yieRice dwarf virus (RDV), Rice black streaked dwarf virus (RBSDV), and RRSV, negative-sense single-stranded RNA viruses, Rice stripe virus (RSV) and RGSV, a double-stranded DNA virus, Rice tungro bacilliform virus, and a positive-sense single-stranded RNA virus, Rice tungro spherical virus. Almost all these rice viruses are transmitted by leafhoppers and planthoppers, and some multiply in the insects and are transmitted transovarially, making their control more difficult  viruses such as ifficult . These iifficult .Recent advances in biotechnology should help solve these problems, and genetically engineering plants to have improved resistance against diseases and harmful insects is one of the most promising approaches. Based on the concept of pathogen-derived resistance, that the expression of various viral sequences is effective in preventing or reducing various plant virus infections, several strategies to confer resistance against viruses in plants have been developed over the last two decades , and RRSV, occur in rice and threaten rice production in Asia. In addition, a new virus, Southern rice black-streaked dwarf virus (SRBSDV) that was first discovered in 2001 in Guangdong, China, has rapidly spread throughout central China and Vietnam, and has recently been found in northern China and Japan . RRSV, belonging to the genus Oryzavirus, is transmitted in a persistent manner by the brown planthopper (Nilaparvata lugens). RBSDV and SRBSDV, belonging to the genus Fijivirus, are mainly transmitted by the small brown planthopper (Laodelphax striatellus) and the white-backed planthopper (Sogatella furcimera Horváth), respectively. All five of these reoviruses are propagative in their vectors, and RDV and RGDV can be transmitted from female adults to their progeny via eggs. RRSV occurs mainly in the tropical regions of Asia, such as Indonesia, Malaysia, the Philippines, Vietnam, and Thailand, where it causes serious problems for rice production. The other four viruses occur mainly in the subtropical regions of Asia, such as China, Japan, Korea, and Nepal . The viral core particle appears to be formed by viral genomic dsRNA segments and at least four proteins . The core particles are surrounded by one or two outer capsid proteins and form a double-shelled, icosahedral particle approximately 60–80 nm in diameter. In addition to these structural proteins, the viral genomes encode two to five non-structural proteins, which form cytoplasmic inclusion bodies, known as viroplasms . A simple and elegant assay for RNAi suppressor activity that involves a combination of green fluorescent protein (GFP)-silenced reporter plants and eveloped .A large number of RNA silencing suppressor proteins have been identified from numerous plant viruses . In the Figure 1), the degrees of resistance that were conferred to rice differed (Table 1).RNA interference has been an important tool to render plants resistant against virus infections. During our work to develop resistance against RDV in rice plants by introducing dsRNAs of a 500-bp fragment in the 5′-proximal regions of each viral genes as the viral target genes . The transgenic plants did not contain detectable amounts of the virus through harvest as determined by ELISA. In contrast, transgenic plants with an introduced construct for P2 (outer capsid), P5 (capping enzyme), P7 (nucleic acid binding protein), P9 (outer capsid), or Pns10 (silencing suppressor) did not develop any resistance against RDV; symptoms developed at the same rate and severity as those in the susceptible non-transgenic control plants.The transgenic rice plants with the introduced RNAi construct targeting the RDV gene for Pns 6 (viroplasm associated protein and movement protein), P8 (major outer capsid), and Pns12 (viroplasm associated protein) were almost immune to RDV infection. There were no apparent differences in morphology or growth, based on plant height, number of tillers, and rice grain yields between inoculated and mock-inoculated rice plants .All transgenic plants with the introduced RNAi trigger construct of the RGDV gene for Pns9 were asymptomatic and continued to be symptom-free until harvest (ca. 4 months), whereas growth of the RGDV-infected non-transgenic rice plants was severely stunted and small galls had developed along the leaf veins on the abaxial surface of leaves and on the outer surface of sheaths by 4 weeks post-inoculation. The transgenic rice plants that remained asymptomatic after challenge with RGDV, were almost immune to RGDV infection because the transgenic plants did not contain detectable amounts of the virus, as determined by ELISA. In addition, no apparent differences in morphology or growth, based on plant height, number of tillers, and rice grain yields were observed between transgenic and mock-inoculated non-transgenic rice plants .Similarly, the transgenic rice plants that harbored the RNAi trigger plasmid that inhibits the expression of the RBSDV gene for P9-1 were completely resistant against RBSDV infection and remained asymptomatic with no virus detectable by ELISA after challenge with RBSDV. In contrast, the RBSDV-infected non-transgenic rice plants were severely stunted with darkened leaves, twisted leaf tips, split leaf margins, and waxy white-to-black galls along the veins on the adaxial surface of leaf blades and the adaxial surface of sheaths by 4 weeks post-inoculation  are known to cause severe damage to rice. RSV is transmitted in a persistent manner by the small brown planthopper and induces significant economic losses in temperate regions of East Asia, especially in China, Japan, and Korea. RGSV, transmitted to rice plants in a persistent manner by the brown planthopper, has become a serious problem for rice production in South, Southeast, and East Asian countries  and negative (virion complementary-sense) polarities (Table 2). The pC1 encoded in the first RNA segment of the Tenuivirus genome contains the major RNA-dependent RNA polymerase modules and RNA-dependent RNA polymerase activity  for evaluating resistance against RSV infection . The transgenic plants with the RNAi trigger plasmids of RSV genes for pC3 (nucleocapsid protein) and pC4 (movement protein) were conferred near immunity to RSV infection because the virus was not amplified in the transgenic rice plants through harvest (ca. 4 months). Furthermore, morphology and growth, based on plant height, number of tillers, and rice grain yields apparently did not differ between the transgenic and mock-inoculated non-transgenic rice plants . In contrast, the transgenic plants with the introduced pC2 or p4 did not have any resistance against RSV infection; symptoms developed at the same rate and severity as in the susceptible non-transgenic control plants. Transgenic rice plants with the p2 and p3 constructs exhibited moderate resistance against RSV infection; typical symptoms were induced but their appearance was delayed for 2–4 weeks, and plant growth was moderately stunted by RSV infection.The transgenic rice plants with the introduced RNAi trigger construct of the various individual RSV genes exhibited varying degrees of resistance against RSV infection . These results indicated that the RGSV genes for the nucleocapsid protein and movement protein are the viral “Achilles’ heel” to target for RNAi attack and provided further evidence that targeting these genes are effective in conferring strong resistance against tenuiviruses in transgenic rice plants. Our strategy for interfering with the expression of the nucleocapsid protein and movement protein should also be effective for controlling other tenuiviruses. For example, the genes for pC3 and pC4 in RHBV, which causes economically important rice crop plants in Central and South America, are promising candidates to confer strong resistance against RHBV infection in rice plants.All the transgenic plants with the introduced RNAi trigger constructs for pC5 and pC6 were asymptomatic at 4 weeks post-inoculation, in contrast to the typical severe stunting of plant growth with profuse tillering of all infected non-transgenic plants, and they continued to be symptom-free and with no detectable amounts of the virus until harvest (ca. 4 months). In addition, no apparent differences in morphology or growth, based on plant height, number of tillers, and rice grain yields were observed between transgenic and mock-inoculated non-transgenic rice plants . To increase Japan’s self-sufficiency for livestock feed, the production of forage rice cultivars is strongly promoted by the Japanese government, and significant progress in research on forage rice cultivars has resulted in several new rice cultivars that produce large gross weights.From the 1960s on, the production of livestock feed in Japan has decreased dramatically to only 26% of the total consumed by 2012, critically impairing the ability to maintain stable production of livestock . These results indicated that targeting the genes for the nucleocapsid protein and the viroplasm associated protein are effective in conferring strong resistance against the plant-infecting tenuivirus and reovirus, respectively, not only in the edible rice cultivar Nipponbare but also in the forage rice cultivars Tachisugata and Tachiaoba. Furthermore, simultaneously using the fused chimeric gene construct for the nucleocapsid protein and the viroplasm associated protein is effective in conferring strong resistance against both the viruses.All the transgenic forage cultivar plants with the introduced RNAi trigger construct for RSV pC3 and the RDV Pns12 continued to be symptom-free and did not contain detectable amounts of these viruses through harvest (ca. 5 months), whereas the RSV- and the RDV-infected non-transgenic forage cultivar plants developed typical severe symptoms by 4 weeks post-inoculation. These transgenic forage cultivar plants were almost immune to RSV and RDV infections. In addition, no apparent differences in morphology or growth, based on plant height, number of tillers, and grain yield, were observed between transgenic and mock-inoculated non-transgenic forage cultivar plants (Rice viruses cause significant economic losses in rice production in South, Southeast, and East Asian countries. The use of insecticides against insect vectors is one of the most effective approaches to prevent damage and yield loss from rice viruses, but the high cost is a major burden on rice growers, and the continuous usage of certain insecticides is likely to result in the insect vectors developing resistance against the insecticide . ExploitThe use of RNAi is an effective, more promising method to confer strong resistance against rice viruses. When developing transgenic rice plants with strong resistance against rice viruses, it is important to target viral genes that play important roles in viral infection and proliferation at an early stage of viral replication. Furthermore, the spectrum of RNA-mediated virus resistance is generally restricted to viral strains with greater than ≈90% sequence identities with the introduced transgenes . When weThese transgenic techniques to confer strong resistance against virus infection are a promising approach to control viral diseases and should contribute greatly to ensuring a stable food supply in Asian countries burdened with viral disease. It is important to advance research on the development of virus-resistant transgenic rice plants, although there are many obstacles that must be overcome to actually cultivate such virus-resistant transgenic rice plants in these areas. Other than transgenic papaya resistant against papaya ring spot virus , no tranThe 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.


GAA gene. In the literature, heterozygous individuals are usually considered to be asymptomatic, although they can have reduced enzymatic activity. Since enzyme replacement therapy (ERT) became available in 2006, it has improved the prognosis for severe infantile-onset Pompe disease, as well as for late-onset forms by improving muscle/respiratory function and/or stabilizing clinical progression. Because the disease is now treatable, it is essential to understand which patients may benefit from ERT.Late-onset glycogen storage disease type 2 (GSD2) is a genetic but heterogeneous disorder, which may present anywhere along a continuum of severity from an isolated hyperCKemia to a profound, generalized muscle weakness with pulmonary involvement. The gold standard for diagnosis is confirmation of low or absent levels of acid alpha-glucosidase (GAA) enzyme activity , which is confirmed only in some cases by molecular analysis of the In the database of the Centre for Neuromuscular Diseases, we found 7 patients with only one mutated GAA allele: 2 female patients showed proximal weakness, pathologic muscular biopsy and reduced GAA enzyme activity in muscle tissue. These patients started ERT four years ago, and now there is no evidence of disease progression. The other 5 subjects  have mild signs of myopathy  or isolated hyperCKemia. Muscle biopsies showed non-specific signs, and reduced enzymatic activity (below 40%) was confirmed in all patients using at least two methods (dried blood spot and/or leukocytes and/or muscle homogenate).Heterozygotes with one GAA gene mutation are not always asymptomatic individuals; in our experience, they can develop a mild myopathy, have non-specific muscle biopsy results, and reduced GAA enzyme activity. We followed and monitored this cohort of patients (not receiving ERT) and found that they did develop clinical evidence of disease. In conclusion, mild symptomatic subjects and heterozygotes are an emerging group of patients. Further molecular investigations and follow-up are required to identify patients in this cohort that may benefit from ERT.


N-methyl-d-aspartate (NMDA) receptor dysfunction in the pathogenesis of schizophrenia and in the appearance of negative symptoms and cognitive dysfunctions. In line with this notion, several gene variants affecting the NMDA receptor’s pathway have been reported to increase susceptibility for schizophrenia, and have been investigated using the imaging genetics approach. In recent years, several attempts have been made to develop medications modulating the glutamatergic pathway with modest evidences for efficacy. The most successful approaches were those that aimed at influencing this pathway using compounds that enhance NMDA receptor function. More recently, the selective glycine reuptake inhibitor bitopertin has been shown to improve NMDA receptor hypofunction by increasing glycine concentrations in the synaptic cleft. Further research is required to test whether pharmacological agents with effects on the glutamatergic system can help to improve the treatment of negative symptoms in schizophrenic disorders.Schizophrenia is characterized by positive, negative, and cognitive symptoms. While positive symptoms occur periodically during psychotic exacerbations, negative and cognitive symptoms often emerge before the first psychotic episode and persist with low functional outcome and poor prognosis. This review article outlines the importance of modern functional magnetic resonance imaging techniques for developing a stratified therapy of schizophrenic disorders. Functional neuroimaging evidence on the neural correlates of positive and particularly negative symptoms and cognitive deficits in schizophrenic disorders is briefly reviewed. Acute dysregulation of dopaminergic neurotransmission is crucially involved in the occurrence of psychotic symptoms. However, increasing evidence also implicates glutamatergic pathomechanisms, in particular  Neuroimaging techniques have been developed as important tools to investigate brain dysfunctions that underlie psychiatric disorders. In particular, modern functional magnetic resonance imaging (fMRI) holds the promise to provide neurofunctional biomarkers for improved diagnosis, prognosis, and optimized treatment of mental disorders . In tIn traditional psychiatry, mental disorders are diagnosed and classified on the basis of more or less specific psychopathological symptoms in the course of the disorder. Numerous recent findings from modern systems neuroscience and molecular neuroscience strongly suggest that diagnoses made on the basis of psychopathological criteria do not represent “natural disease entities” in the sense of diseases with uniform pathogenesis and pathology . TDuring the last two decades, modern brain imaging techniques have allowed for the first time scientific investigations into the neural correlates of different symptom dimensions that characterize schizophrenic disorders. These studies of pathophysiological processes that underlie different psychopathological symptoms and syndromes (an approach that may be termed “psychopathophysiology”) are briefly reviewed in the following.Positive symptoms of schizophrenic disorders such as verbal hallucinations (“hearing voices”) and delusional symptoms are certainly the most impressive characteristics of schizophrenic disorders. Nevertheless, much evidence has been provided that negative symptoms and cognitive disturbances are more strongly associated with the long-term functional outcome of patients suffering from schizophrenia than positive symptoms –14. CognThe positive symptoms of schizophrenic disorders particularly include auditory–verbal hallucinations (“hearing voices”) and delusional symptoms like paranoia. As regards auditory–verbal hallucinations, a number of functional brain imaging studies have been performed in the past. Overall, findings of these studies appear quite heterogeneous. However, a finding that has been replicated several times is overactivation of the superior temporal gyrus during experimental phases in which the patients exhibited the symptom of hearing voices . In Negative symptoms of schizophrenic disorders are usually defined as symptoms representing a qualitative and/or quantitative reduction of mental capacities or qualities of experience. This class of symptoms is relatively heterogeneous and traditionally includes the five “A”s, which are affective flattening, apathy (reduced drive), anhedonia, asociality , and alogia (impoverishment of thought) . Early n-back tasks), Menon et al.  , and seDisturbed social cognitions in schizophrenic disorders include particularly impaired recognition of facial emotional expressions and reduced theory-of-mind capacities. Neuroimaging studies have revealed that deficits in these domains of social cognitions are associated, firstly, with reduced activation in the amygdala and the fusiform gyrus  and, secTaken together, neuroimaging studies on the neural correlates of different  symptom domains in schizophrenic disorders suggest the involvement of different lateral and medial prefrontal, temporal , and subcortical  brain regions in the occurrence of these symptoms.N-methyl-d-aspartate (NMDA) receptor dysfunction may lead to dopaminergic dysregulation in schizophrenic disorders through a complex interaction between glutamatergic and dopaminergic, but also GABA-ergic mechanisms. Schwartz and co-workers (It is well-established that acute dysregulation of dopaminergic (and glutamatergic) neurotransmission is crucially involved in the occurrence of psychotic symptoms, whereas more chronic cellular neuropathology may be responsible for the development of cognitive deficits and negative symptoms . In more-workers , for exa-workers . Such paModern pharmacological and animal research approaches are increasingly focusing on the interactions between the dopaminergic and glutamatergic system, especially within fronto-striato-thalamo-frontal loops and in the interactions between frontal cortex, hippocampus, nucleus accumbens, and VTA. Within and between these brain regions, the dopamine and the glutamate system interact in a very complex way, and dysfunctions in these interactions are a central pathomechanistic explanation for the development of schizophrenic disorders . Pain vivo in patients with schizophrenia, for example using magnetic resonance spectroscopy (MRS). In very recent publications , the function of which has not yet been more closely characterized, but which showed a genome-wide significant association with schizophrenia and also with bipolar disorder , as wellTaken together, the studies summarized here support the important pathophysiological role of glutamate in schizophrenia and encourage further development of therapeutic strategies that target the glutamatergic pathway in schizophrenia.+ and K+ ions, whereas NMDA receptors exhibit a slow gating kinetic and need a predepolarization of the neuronal membrane for activation by glutamate binding. This predepolarization occurs when vicinal AMPA receptors are frequently activated and leads to the release of a blocking Mg2+ ion from the NMDA receptor. Activated NMDA receptor channels are not ion specific and pass Ca2+, Na+, and K+ ions, which leads not only to further depolarization but also intracellular processes making the synapse more sensible for signals from upstream and sending stronger signals downstream. This so-called long-term potentiation (LTP) provides the basis for synaptic and dendritic proliferation or pruning, learning, and memory  . The inhd-serine .d-serine, and sarcosine significantly improved multiple symptom domains, whereas no symptom domain was improved by d-cycloserine. Furthermore, glycine, d-serine, and sarcosine were found to be superior to d-cycloserine in improving overall psychopathology . Such tg., Ref. . Moreoveg., Ref. ].Oliver Gruber was honorary speaker for the following companies: Astra Zeneca, Bristol Myers Squibb, Janssen Cilag, Lilly, Lundbeck, Otsuka, Servier. Oliver Gruber has been invited to scientific congresses by Astra Zeneca, Janssen Cilag, Pfizer, Servier. Oliver Gruber has received a research grant from Servier and a publication grant from Roche. Antonella Chadha Santuccione and Helmut Aach are full employes of Roche Pharma AG, Grenzach, Germany.


Although there are small reported series of patients undergoing the Extracardiac Total cavopulmonary connection without cardiopulmonary bypass, there is paucity of data comparing the results of the two.Between February 2012 and February 2013, 27 patients undergoing Total cavopulmonary connection without cardiopulmonary bypass (off-pump group) were compared with propensity score matched 27 patients undergoing Total cavopulmonary connection on cardiopulmonary bypass (on-pump group). Outcome parameters studied were inotropic score, time to extubation, intensive care unit stay, mediastinal drainage in the intensive care unit, daily pleural drainage, time to removal of chest tubes, hospital stay and saturation at discharge.There was one early death in each group. No patient required conversion from off pump to cardiopulmonary bypass. The inotropic score , time to extubation , mediastinal drainage in intensive care unit  and intensive care unit stay  were significantly less in off pump group as compared to on-pump group and saturation at discharge  was higher in the off-pump group. However the daily pleural drainage , time to removal of chest tubes  and the total hospital stay  were no different. There were substantial savings in costs in patients undergoing off-pump procedure.Extracardiac Total cavopulmonary connection without cardiopulmonary bypass is easy to perform, is cost effective, and is associated with superior early post-operative outcomes. With appropriate modifications, this operation can be performed in almost all morphological subsets of patients who do not need an associated intracardiac procedure.


Antipsychotic drugs have thus far focused on dopaminergic antagonism at the D2 receptors, as counteracting the hyperdopaminergia in nigrostriatal and mesolimbic projections has been considered mandatory for the antipsychotic action of the drugs. Current drugs effectively target the positive symptoms of psychosis such as hallucinations and delusions in the majority of patients, whereas effect sizes are smaller for negative symptoms and cognitive dysfunctions. With the understanding that neurocognitive dysfunction associated with schizophrenia have a greater impact on functional outcome than the positive symptoms, the focus in pharmacotherapy for schizophrenia has shifted to the potential effect of future drugs on cognitive enhancement. A major obstacle is, however, that the biological underpinnings of cognitive dysfunction remain largely unknown. With the availability of increasingly sophisticated techniques in molecular biology and brain imaging, this situation is about to change with major advances being made in identifying the neuronal substrates underlying schizophrenia, and putative pro-cognitive drug targets may be revealed. In relation to cognitive effects, this review focuses on evidence from basic neuroscience and clinical studies, taking two separate perspectives. One perspective is the identification of previously under-recognized treatment targets for existing antipsychotic drugs, including myelination and mediators of inflammation. A second perspective is the development of new drugs or novel treatment targets for well-known drugs, which act on recently discovered treatment targets for cognitive enhancement, and which may complement the existing drugs. This might pave the way for personalized treatment regimens for patients with schizophrenia aimed at improved functional outcome. The review also aims at identifying major current constraints for pro-cognitive drug development for patients with schizophrenia. Schizophrenia is a severe mental disorder with typical onset in the late teens or early adulthood and a chronically relapsing remitting course in the majority of cases . SchizopThe clinical picture of schizophrenia is heterogeneous, but in the vast majority of patients, cognitive dysfunctions are present with adverse impact on daily functioning . AntipsyRecognizing the large impact that the schizophrenia associated cognitive dysfunctions have on functional outcome , 16, theCognitive function may be understood in terms of inter-related complex neural networks, influenced by different neurotransmitters, cytokines, and other substances including brain-derived neurotropic factor (BDNF) acting as neuromodulators .Cognitive deficits are viewed as core characteristics of schizophrenia, with clinically significant cognitive impairments observed in a large majority of patients, and most patients experience lower cognitive functioning than would be expected from parental levels of education , 25. CogA significant challenge has been to develop clinical meaningful measures of cognitive dysfunction for pro-cognitive drug advancement. A major contribution to establish a standardized and manageable test battery for measuring cognition in schizophrenia has been the development of the Measurement and Treatment Research to Improve Cognition in Schizophrenia (MATRICS) Consensus Cognitive Battery (MCCB) . The MCCMyelin, the main constituent of white matter, is essential for controlling and regulating conduction velocities along axons and thus the synchronicity of brain signals across different brain regions, and for controlling synapse plasticity . DecreasSeveral distinct alterations in gray and white matter are well established for schizophrenia patients as a group . ReviewsRecently, also related to myelination, the search for brain alterations underlying the psychopathology of schizophrenia has refocused to examine neuronal dysconnectivity, i.e., abnormal communication between local and distributed neuronal circuits or disrupted integration of brain activation –54. FornDisturbed connectivity within the frontal lobes has been found to be related to working memory and to executive functioning , 54. ThiOf future interest may be the influence of antipsychotic drugs on the dynamic interaction between large-scale cortical networks related to resting and effort-mode states . Using fThe major question related to the structural basis of functional dysconnectivity was addressed in the review by Fornito et al. . The autSeveral methodological issues need consideration regarding the use of imaging techniques for myelin assessments. The DTI signal may reveal changes in white matter integrity but has limitations in identifying the exact nature of these changes, as the FA reflects different processes like demyelination, axonal swelling, or atrophy, and is sensitive to confounding effects of fiber crossings . In a reA study applying graph theory to analyze data from DTI combined with MTR showed that patients with schizophrenia have a weaker globally integrated structural brain network when compared to healthy controls . The samCompelling evidence from several different lines of research has, in recent years, implicated dysfunctional myelin and oligodendrocytes, the cells responsible for wrapping myelin around neuronal axons in the brain, in the pathology of schizophrenia and related psychoses , 64–66. Normal myelination starts in the late part of fetal life and occurs most rapidly during the first 2 years after birth, but continues to adulthood in a region- and brain matter-specific manner , 65, 67.N-methyl-d-aspartate (NMDA) receptor antagonists, such as phencyclidine (PCP) and ketamine, have the potential to induce not only positive symptoms of psychosis but also negative symptoms and cognitive dysfunction resembling those seen in schizophrenia  system, and these lipogenic effects have been suggested to contribute to myelin-stimulating effects of antipsychotic agents  by Amminger et al. , a markeSeveral findings point to a link between inflammatory processes and the pathophysiology of schizophrenia: (1) activated peripheral inflammatory system and neuroinflammation in patients with schizophrenia , 95, (2)In the following sections, we highlight some of the main findings related to inflammation/immunology and schizophrenia, with the specific purpose of evaluating the status of immune-modulating treatment with cognitive-enhancing effects.In the context of inflammatory changes in schizophrenia, the majority of findings stem from the innate system, but components of the adaptive immunology system have also been implicated. The macrophages of the innate system induce the release of acute-phase proteins  as well as producing and releasing cytokines , all mar2 (PGE2), CRP] and elevated monocyte counts and activated immune cells have been associated with schizophrenia , a partial agonist at the glycine site of the NMDA receptor, was also found to reduce the levels of KYNA in human post-mortem frontal cortex homogenates by dose-dependently blocking KAT  , 111, moin vitro  also havin vitro . Interesin vitro . Cerebroin vitro  and has in vitro , 127 andin vitro . In anotking KAT . DSC hasking KAT .In addition to elevated KYNA/QUIN, other aspects of an activated brain immune system can also have clinically important effects in schizophrenia. The proinflammatory cytokine IL-1β has been linked to glutamatergic excitotoxicity , and cloThe neurotrophin BDNF is among the substances secreted by immune cells during inflammation and immune responses , and an Structural brain alterations associated with immune-related genetic polymorphisms were recently reviewed by Fineberg and Ellman . The revin vitro and animal studies) concerning the capability of antipsychotic drugs to influence activated microglia. The review identified several studies showing that antipsychotic drugs significantly reduce the secretion of TNF-α, nitric oxide, IL-1β, and IL-2 from activated microglia. Furthermore, some drugs were found to have stronger inhibitory effects, e.g., risperidone, which inhibited the secretion of several cytokines from activated microglia more than haloperidol, and indications of clozapine-specific effects have also been reported. Moreover, in the context of the kynurenine pathway, one animal study demonstrated that chronic treatment with antipsychotic drugs reduces brain KYNA , six with celecoxib (n = 504)] to different antipsychotics showed non-significant benefit over placebo  in schizophrenia. The pooled effects size in reducing total Positive and Negative Syndrome Scale (PANSS) score according to a recent meta-analysis of the effect of add-on treatment with NSAIDs [eight studies, two with aspirin ( placebo . Treatme placebo . When th placebo . At pres placebo .n = 39) with stable schizophrenia patients, treatment with recombinant human EPO (40000 IU/week) improved neurocognitive function compared to placebo in the domains of delayed memory, language-semantic fluency, attention and perseverative errors (Erythropoietin (EPO) is a cytokine with several identified functions in the brain . In a 12e errors . An evale errors . Animal e errors . A systee errors . EPO hase errors  and multe errors .n = 182 patients given minocycline, and n = 166 on placebo, the effects on cognition were not reported, but no significant effects on overall symptom severity were identified.The tetracycline antibiotic drug minocycline has also been tested as an add-on treatment for patients with schizophrenia, based on evidence from animal studies that showed minocycline to have multiple actions including inhibition of microglial activation and the attenuation of adaptive immunity through the reduction of activity and expression of matrix metalloproteinases (MMPs). MMPs enable T-cells to migrate through the BBB by altering its permeability, a process associated with myelin degradation . In a pln-acetylcysteine (n = 140), aspirin (n = 270), and estrogens (n = 262) were identified, while studies with davunetide and PUFAs (eicosapentanoic acid and docosahexanoic acids) did not show significant effects.The meta-analysis by Sommer et al.  also invN-acetylcysteine, estrogens, aspirin) have broad mechanisms of action, and it is not at all demonstrated that the improved symptoms are caused by anti-inflammatory actions. A further critical question to address in future drug research will be to establish reliable brain imaging methods to quantitatively assess neuroinflammation, as the levels of peripheral cytokines are only an indirect measure of brain neuroinflammation. PET studies with new ligands that specifically target activated microglia and the “free-water” MRI scanning seem promising, but extensive development remains before these methods are ready as outcome measures in drug discovery studies.The involvement of inflammatory/immunological factors in the pathophysiology of a large portion of patients with schizophrenia is well established through different lines of research, and data point to several links between these factors and cognitive dysfunction. Presently, many drugs with anti-inflammatory or immunomodulatory action have been tested (as add-on to antipsychotic treatment) for patients with schizophrenia, and while some have shown positive effects for global schizophrenia symptoms, the effects on cognition were not possible to assess in the recent meta-analysis by Sommer et al. , as onlyn-acetylcysteine have shown promising results in single studies, but have not yielded straightforward support for the use in clinical practice to enhance cognition.At present, pharmacological treatment of schizophrenia relies on antipsychotic drugs, which predominantly relieve positive psychotic symptoms and have little effect on the cognitive dysfunctions restricting the functional level of patients. However, recent developments in brain imaging, including novel specific PET ligands and MRI paradigms specifically investigating myelin integrity, neurotransmitter levels, and neuroinflammation, facilitate the unraveling of mechanisms underlying cognitive dysfunction in schizophrenia. Accumulating evidence supports a combined model including all these areas of pathology underlying the cognitive deficits in schizophrenia, schematically exemplified by Figure Drugs that would reduce brain levels of KYNA  are expected to improve cognitive dysfunctions in schizophrenia based on animal studies, but remain to be developed for clinical use. The possibility of pro-cognitive effects of drugs that have been used to treat other medical conditions for years, e.g., EPO, minocycline, and aspirin is attractive, also because the safety profile of many of these drugs are well known in neurological patients populations, reducing the costs of introducing the drugs as cognitive enhancers for schizophrenia patients. Several critical questions currently constraining progress remain to be solved, however. Firstly, uniformly accepted and standardized cognitive assessments for repeated measures must be agreed on for pro-cognitive drug studies in schizophrenia patients. Secondly, the refinement of brain imaging methods unto sufficient reliability and specificity  for use as outcome measures in pro-cognitive drug is essential for studies of putative cognition enhancers in humans. Thirdly, and at least of prominent importance in the field of further developments of pro-cognitive glutamatergic substances are the problems of translating findings in animal studies to human drug treatment.However, even though the process of developing novel pharmacological agents is highly sophisticated, identifying novel treatment targets through thorough clinical and preclinical studies remains pivotal in the continued search for improved treatment of schizophrenia. The convergence of a disordered inflammatory system, disturbances in myelination/oligodendrocyte function, and transmitter dysfunctions in schizophrenia open new paths for pro-cognitive drug discovery with putative large functional improvements to be achieved for patients with schizophrenia.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.


Magnetic resonance imaging (MRI) provides a safe, noninvasive method to examine the brain’s macrostructure, microstructure, and some aspects of how the living brain functions. MRI is capable of detecting abnormalities that can occur with alcoholism as well as changes that can occur with sobriety and relapse. The brain pathology associated with chronic excessive alcohol consumption is well documented with imaging of the living body . Consistent findings include shrinkage of the frontal cortex, Alcohol use disorders are characterized by the excessive consumption of alcohol despite its interference with an individual’s physical, mental, interpersonal, and social well-being. These harmful behavioral effects are mediated through the brain, which can undergo changes in structure, function, and basic physiology. Some studies e.g.,  have shoThis article reviews studies using three different types of magnetic resonance imaging (MRI)To test whether the effects of excessive alcohol consumption persist after sobriety is maintained, investigators may compare alcoholics with different lengths of sobriety or preferably follow the same people over time and retest them after varying periods of sobriety. Importantly, these longitudinal studies also require retesting a comparison group of low-alcohol drinkers to control for normal changes in aging and distortion inherent to MRI  over time. Tests to measure the extent and time-course of such recovery in humans typically are initiated while patients are in alcohol treatment. Such tests track the effects of withdrawal and short-term sobriety. Follow-up studies require tracking patients after discharge, when they have moved back into the community and either maintained sobriety or relapsed into drinking. Longer-term studies therefore take the form of naturalistic rather than controlled experiments because the investigator has no control over whether patients will maintain sobriety or resume drinking and what level of drinking will be embraced. Furthermore, some participants will drop out of the study, affecting the representativeness and size of the followup sample.Even cross-sectional comparisons of problem drinkers with light drinkers must consider that many factors in addition to alcohol consumption may differentiate the groups. Many alcoholic patients also have comorbidities that can affect the brain, including mood disorders, abuse of other substances, and infection from the hepatitis C virus. Thus, investigators performing these studies ideally must screen study participants for these other illnesses and conditions. Furthermore, people with alcoholism may suffer from occult liver disease, malnutrition, and head trauma and are more likely to be chronic smokers than people who are not dependent on alcohol. Each of these factors has its own consequence on the brain . SamplesConventional structural magnetic resonance imaging (MRI) takes advantage of the fact that different tissue types in the brain contain different proportions of water, which influences their MRI-visible signal see . Gray maMost brain-imaging research focuses on alcohol-dependent individuals recruited through treatment programs. However, the majority of people who meet the criteria for alcohol dependence never seek treatment for their condition . Some trThe following sections examine MRI evidence for brain abnormalities on both macrostructural and microstructural levels . These in vivo findings are consistent with postmortem reports of shrinkage, prominent in large neurons in part of the cerebellum known as the anterior superior vermis  see  across bBoth postmortem  and in vA recent DTI study using quantitative tractography to investigate the integrity of white matter fiber bundles revealed signs of fiber tract degradation, particularly of myelin, in frontal and superior brain regions  of alcoholics relative to controls . Greater lifetime alcohol consumption by alcoholic men correlated with poorer condition of some of these fiber bundles. When matched for alcohol exposure, alcoholic women showed more DTI signs of white matter degradation than alcoholic men, suggesting that women are at enhanced risk for alcoholism-related degradation in selective white matter systems. Another DTI study reported that detoxified alcoholics had nearly 20 percent fewer fibers per unit volume of white matter in tracts between the midbrain and pons, which was predictive of poorer performance on a test of mental flexibility .Despite its neuroanatomical detail, conventional magnetic resonance imaging (MRI) typically does not reveal information about the microstructure of brain tissue and its components, such as axons, and myelin in white matter or cell orientation in gray matter. By contrast, diffusion tensor imaging (DTI) measures the diffusion of water molecules within brain cells and in extracellular spaces by making the following assumptions: when unconstrained by barriers such as cell membranes , water molecules move equally in all directions, and this movement is called isotropic, meaning the same in every direction. However, in tissue with a regular and orderly microstructure, such as brain white matter , the wat— Margaret J. Rosenbloom, and Adolf Pfefferbaum, M.D.ArfanakisKHaughtonVMCarewJDDiffusion tensor MR imaging in diffuse axonal injuryAmerican Journal of Neuroradiology23794802200212006280HorsfieldMAJonesDKApplications of diffusion-weighted and diffusion tensor MRI to white matter diseases: A reviewNMR in Biomedicine15570577200212489103Le BihanDLooking into the functional architecture of the brain with diffusion MRINature Reviews Neuroscience4469480200312778119Le BihanDThe ‘wet mind’: Water and functional neuroimagingPhysics in Medicine and Biology52R57R90200717374909MoriSZhangJPrinciples of diffusion tensor imaging and its applications to basic neuroscience researchNeuron51527539200616950152PfefferbaumASullivanEVDiffusion MR imaging in neuropsychiatry and agingGillardJWaldmanABarkerPClinical MR Neuroimaging: Diffusion, Perfusion and SpectroscopyCambridgeCambridge University Press2005558578PierpaoliCBasserPJTowards a quantitative assessment of diffusion anisotropyMagnetic Resonance in Medicine3689390619968946355WaxmanSGKocsisJDStysPKThe Axon: Structure, Function and PathophysiologyNew YorkOxford University Press1995Neuroimaging studies have documented a range of consequences of chronic excessive alcohol use, including volume deficits in the frontal lobes and cerebellum and compromised integrity of white matter microstructure.What are the practical consequences of these changes in terms of deficits in cognitive and motor function? A significant percentage of recovering chronic alcoholics exhibit mild-to-moderate deficits in complex cognitive processes. Importantly, functions tend to be impaired but not completely lost. Typically, the processes affected are visuospatial abilities; psychomotor speed; executive functions, such as working memory, problem solving, temporal ordering, and response inhibition; and gait and balance 13th Proceedings of the International Society for Magnetic Resonance in MedicineMiami, FL2005(Abstract no. 1337)LehericySDucrosMVan De MoortelePFDiffusion tensor fiber tracking shows distinct corticostriatal circuits in humansAnnals of Neurology55522529200415048891MoriSWakanaSNagae-PoetscherLMVan ZijlPMCAn Atlas of Human White MatterAmsterdam, The NetherlandsElsevierr B.V.2005SchmahmannJDPandyaDNWangRAssociation fibre pathways of the brain: Parallel observations from diffusion spectrum imaging and autoradiographyBrain130630653200717293361StieltjesBKaufmannWEVan ZijlPCDiffusion tensor imaging and axonal tracking in the human brainstemNeuroImage14723735200111506544SullivanEVAdalsteinssonEPfefferbaumASelective age-related degradation of anterior callosal fiber bundles quantified in vivo with fiber trackingCerebral Cortex1610301039200616207932XuDMoriSSolaiyappanMA framework for callosal fiber distribution analysisNeuroImage1711311143200212414255fMRI studies of alcoholics suggest the importance of cerebellar activation in functions that otherwise would be frontal lobe tasks and the activation of frontal regions in functions that otherwise would be lower-level tasks. One interpretation is that this additional activation enables alcoholics to achieve normal levels of coordinated performance despite evidence for cerebellar dysmorphology but at a cost to processing capacity. This functional style observed in alcoholics, which may be compensatory, has been characterized as “processing inefficiency” . ProcessThe dynamic course of change in the “incomplete lesion” that characterizes alcoholism makes it a special model for human neuroscience study. Certain brain structural abnormalities are at least partially reversible with abstinence, perhaps through remyelination, creation of new neurons , or simple cellular revoluming, and are accompanied by improvement in cognitive, sensory, and motor functions. Indeed, more than 20 years ago, More recent longitudinal MRI studies of alcoholics during short-term treatment–related abstinence, followed by continued abstinence or relapse after discharge, have found that with short-term (about 1 month) abstinence from alcohol, cortical gray matter , overallAnimal studies have revealed neurogenesis in the hippocampus in long-abstinent animals . AlthougIn studies of extended sobriety , research focuses on comparing those who maintained sobriety with those who resumed drinking . Long-teb), but at least a measurable degree of recovery typically accompanies prolonged sobriety, suggesting that the changes observed with neuroimaging have functional consequences.A growing number of longitudinal neuropsychological studies report significantly better scores on tests of working memory, visuospatial abilities, and gait and balance with abstinence from alcohol. Some components of these functional domains recover faster  or more Sullivan et al. 2000The magnetic resonance imaging (MRI) and diffusion tensor imaging (DTI) techniques described above each provide a static representation of the brain. By contrast, functional MRI (fMRI) exploits the MRI-visible signal contrast between oxygenated  and deoxygenated  hemoglobin as it flows through small blood vessels in given brain regions. Neural activity while performing a cognitive, motor, or sensory task increases the ratio of oxygenated to deoxygenated hemoglobin in the blood of neighboring vasculture and enhances the MR signal. This blood oxygen level– dependent (BOLD) contrast mechanism does not directly measure blood flow or neuronal activity but rather the small, rapid changes in the blood’s paramagnetic properties (related to unpaired electrons in the blood) that can be imaged by rapid sampling over the spatial domain . ChangesMargaret J. Rosenbloom, and Adolf Pfefferbaum, M.D.— AdalsteinssonESullivanEVPfefferbaumABiochemical, functional and microstructural magnetic resonance imaging (MRI)LiuYLovingerDMMethods in Alcohol-Related Neuroscience ResearchBoca Raton, FLCRC Press2002345372BucknerRLLoganJMFunctional neuroimaging methods: PET and fMRICabezaRKingstoneAHandbook of Functional Neuroimaging of CognitionCambridge, MAMIT Press20012748BuxtonRBIntroduction to Functional Magnetic Resonance Imaging: Principles & TechniquesCambridge, UKCambridge University Press2002FristonKJModels of brain function in neuroimagingAnnual Review of Psychology565787200515709929HennigJSpeckOKochMAWeillerCFunctional magnetic resonance imaging: A review of methodological aspects and clinical applicationsJournal of Magnetic Resonance Imaging18115200312815634LogothetisNKPfeufferJOn the nature of the BOLD fMRI contrast mechanismMagnetic Resonance Imaging2215171531200415707801TomaKNakaiTFunctional MRI in human motor control studies and clinical applicationsMagnetic Resonance in Medical Science1109120200216082132Several studies have demonstrated that improvements in brain structure may be associated with cognitive improvements. In one study, the short-term recovery of hippocampal volume over the first month of abstinence was associated with improved visuospatial memory but only in non-smoking alcoholics b. In anoThe abstainers showed improvement in general memory relative to the control participants, a behavioral change that was associated with reduced volume of the lateral ventricle. The abstainers also showed improvement in balance, which was associated with reduced volume of the fourth ventricle. The lateral and fourth ventricle are each adjacent to brain structures associated with either memory or balance, suggesting that structural brain changes could have contributed to the improved memory and balance seen in these 2-year abstinent alcoholics . These fAlthough there is substantial evidence now for restoration of alcohol-impaired brain structure and function with sobriety, investigators do not yet know the mechanism for either loss of brain tissue volume with drinking or its restoration with abstinence . ChangesMany of the complexities of studying the effects of chronic excessive alcohol consumption on the brain in humans can be controlled, to some extent, by studying laboratory animals that model human alcoholism using in vivo neuroimaging techniques. To model human alcoholism, animals should at a minimum consume large amounts of alcohol, either voluntarily or by experimental exposure, and develop tolerance and withdrawal symptoms.The rat provides a particularly useful animal model for neuroimaging studies of alcoholism because it is a suitable size for in vivo imaging a and becA 1-year study of genetically selected alcohol-preferring rats, which voluntarily drank large amounts of alcohol, found sustained ventricular enlargement and stunting of corpus callosum growth, possibly modeling the human condition a. FollowStudies using in vivo MR imaging have clearly documented that chronic excessive alcohol consumption leads to brain pathology. Some of this pathology, such as white matter volume reduction, is reversible with abstinence, but some appear to be enduring. Research also has demonstrated the functional consequences of the pathology. Structural imaging studies have shown correlations between brain morphology and quantitative neuropsychological testing, and functional imaging studies provide evidence for compensation of cognitive deficits.The myriad associated and difficult-to-control concomitants of alcoholism , the antecedents , and the consumption patterns  all may influence the observed brain changes associated with alcoholism. As such, they present unique challenges and opportunities to understand the underlying mechanism of alcoholism-induced neuropathology. Given the evidence for structural and functional repair and recovery in sober alcoholics, at least a portion of the neuropathology must be transient. This transience can be followed rigorously with animal models over time and may account for difficulties in finding specific relationships between brain structure, volume, and function in alcoholics but should provide hope for the sober alcoholic. Nonetheless, the dynamic course of alcoholism presents an important and challenging neuroscience model for understanding mechanisms of neurodegeneration, functional recovery, compensation, and processing limitations that should be applicable to any neurological condition characterized by a fluctuating course.


The wide application of next-generation sequencing (NGS), mainly through whole genome, exome and transcriptome sequencing, provides a high-resolution and global view of the cancer genome. Coupled with powerful bioinformatics tools, NGS promises to revolutionize cancer research, diagnosis and therapy. In this paper, we review the recent advances in NGS-based cancer genomic research as well as clinical application, summarize the current integrative oncogenomic projects, resources and computational algorithms, and discuss the challenge and future directions in the research and clinical application of cancer genomic sequencing. Sanger sequencing has dominated the genomic research for the past two decades and achieved a number of significant accomplishments including the completion of human genome sequence, which made the identification of single gene disorders and the detection of targeted somatic mutation for clinical molecular diagnostics possible ,2. DespiThe application of NGS, mainly through whole-genome (WGS) and whole-exome technologies (WES), has produced an explosion in the context and complexity of cancer genomic alterations, including point mutations, small insertions or deletions, copy number alternations and structural variations. By comparing these alterations to matched normal samples, researchers have been able to distinguish two categories of variants: somatic and germ line. The Whole transcriptome approach (RNA-Seq) can not only quantify gene expression profiles, but also detect alternative splicing, RNA editing and fusion transcripts. In addition, epigenetic alterations, DNA methylation change and histone modifications can be studied using other sequencing approaches including Bisulfite-Seq and ChIP-seq. The combination of these NGS technologies provides a high-resolution and global view of the cancer genome. Using powerful bioinformatics tools, researchers aim to decipher the huge amount of data to improve our understanding of cancer biology and to develop personalized treatment strategy. Figure In the last several years, many NGS-based studies have been carried out to provide a comprehensive molecular characterization of cancers, to identify novel genetic alterations contributing to oncogenesis, cancer progression and metastasis, and to study tumor complexity, heterogeneity and evolution. These efforts have yielded significant achievements for breast cancer -12, ovarCancer is primarily caused by the accumulation of genetic alterations, which may be inherited in the germ line or acquired somatically during a cell’s life cycle. The effects of these alterations in oncogenes, tumor suppressor genes or DNA repair genes, allows cells to escape growth and regulatory control mechanisms, leading to the development of a tumor . The proThe sequencing of cancer genomes has revealed a number of novel cancer-related genes, especially in breast cancer. Recently, six papers reported their findings on large breast cancer dataset: TCGA performed exome sequencing on 510 samples from 507 patients , and NikGenomic sequencing has also helped characterize the mutation profile of colorectal cancer. For example, exome sequencing performed on 72 tumor-normal pairs identified 36,303 protein-altering somatic mutations. Further analysis for significantly mutated genes led to 23 candidates that included expected cancer genes such as KRAS, TP53 and PIK3CA and novel genes such as ATM, which regulates the cell cycle checkpoint. RNA sequencing identified recurrent R-spondin fusions, which might potentiate Wnt signaling and induce tumorigenesis . AnotherWhat makes cancer a difficult disease to conquer has much to do with the evolution of cancer that results from the selection and genetic instability occurring in each clone, leading to heterogeneity in tumors . This idThe wide application of NGS has revealed substantial insights into tumor heterogeneity and tumor evolution. Variations between tumors are referred to as intertumor heterogeneity, while variations within a single tumor are intratumor heterogeneity. Intertumor heterogeneity is recognized by different morphological phenotype, expression profiles and mutation and copy number variation patterns, categorizing tumors into different subtypes -31. The Intratumor heterogeneity can be recognized as non-identical cellular clones or subclones within a single tumor, indicating different histology, gene expression, and metastatic and proliferative potential. The ability to generate high-resolution data makes NGS a particularly useful tool for studying intratumor heterogeneity. A recent NGS-based study on renal cell carcinoma from four patients has successfully illuminated intratumor heterogeneity . For patThe ongoing and parallel evolution of cancer cells may establish and maintain intratumor heterogeneity. For example, phylogenetic relationships of the tumor regions in patient 1 and 2 by the renal cell carcinoma study revealed a branching rather than linear evolution of the tumor . StudiesBesides allowing researchers to understand mutations in cancer, NGS has already been applied to the clinic in many areas including prenatal diagnostics, pathogen detection, genetic mutations, and more . AlthougNGS has already been applied in the clinic for cancer diagnosis and prognosis. For example, whole genome sequencing identified a novel insertional fusion that created a classic bcr3 PML-RARA fusion gene for a patient with acute myeloid leukemia and the findings altered the treatment plan for the patient . By sequThere has also been a dramatic increase in the number of clinical trials using NGS technologies since 2010  and variant functional prediction Table . Reads ahttp://cancergenome.nih.gov/). ICGC launched in 2008 and its goal is ‘to obtain a comprehensive description of genomic, transcriptomic and epigenomic changes in 50 different tumor types and/or subtypes which are of clinical and societal importance across the globe’(http://icgc.org/icgc). The Cancer Genome Project (CGP) has many efforts at the Sanger Institute and aims to identify sequence variants/mutations critical in the development of human cancers (http://www.sanger.ac.uk/genetics/CGP/). The NCI’s Cancer Genome Anatomy Project (CGAP) seeks to determine the gene expression profiles of normal, precancer and cancer cells, leading eventually to improved detection, diagnosis and treatment for the patient (http://cgap.nci.nih.gov/). Recently, the Clinical Proteomic Tumor Analysis Consortium (CPTAC) has launched to systematically identify proteins that derive from alterations in cancer genomes using proteomic technologies (http://proteomics.cancer.gov/). The combination of genomic and proteomic initiatives is anticipated to produce a more comprehensive inventory of the detectable proteins in a tumor and advance our understanding of cancer biology.The vast amount of oncogenomics data are generated from large scale collaborative cancer projects Table . The Canhttp://COSMIC[The data and the results from these projects are freely available to the research community Table . A numbe://COSMIC. The cBi://COSMIC. Intogen://COSMIC. The Bro://COSMIC.Although NGS has already helped researchers discover a plethora of information in the field of cancer, challenges in translating the large amounts of oncogenomics data into information that can be easily interpretable and accessible for cancer care still lie ahead. From a computational point of view, many technical and statistical issues remain unsolved. For example, repetitive DNA represents a major obstacle for the accuracy of read alignment and assembly, as well as structure variation detection . FurtherFrom a clinical point of view, a major challenge is to assess genomic variants as potential therapeutic targets. Although many diverse variants are demonstrated to converge on similar deregulated pathways, there is still a lack of pathway-targeted therapies. With the discovery of intra-tumor heterogeneity, questions have been raised about how well a glimpse of a tumor’s genomic landscape can steer the treatment. Currently, many clinicians decide a treatment based on the genetic markers from a few biopsies. Whether these markers are over- or under-represented in the tumor is unknown, causing the selection of treatment to be difficult . In addiTo accelerate the rate of translating genomic data into clinical practice, a sustained collaboration among multiple centers and effective communication among bioinformaticians, statistical geneticists, molecular biologists and physician are required. Bioinformaticians and statistical geneticists are responsible for providing reproducible and accurate analysis, identifying ‘drivers’ in the unstable and evolving cancer genome and building powerful and flexible integrative model to consider interactions among genomic, transcriptomic, metabolomics, proteomics and epigenomic alterations in the context of tumor microenvironment. Biologists interpret and confirm the functional relevance of variants to cancer. Physicians assess relationships of variants to cancer prognosis and response to therapy. Appropriate infrastructure within each research institution that integrates the clinic for patient samples, wet lab for sequencing, and Bioinformatics for data analysis should allow the sequenced data to be processed efficiently, producing results that can create effective personalized therapies applicable to the clinic. In addition, easily accessible and understandable databases that connect genomic findings with clinical outcome are also required. With these efforts and developments, NGS will greatly potentiate genome-based cancer diagnosis and personalized treatment strategies.The authors declare that they have no competing interests.QL led the project. DS drafted the manuscript and QL revised the manuscript. All authors read and approved the final manuscript.


Glioblastoma (GBM) is one of the most common and dismal brain tumors in adults. Further elucidation of the molecular pathogenesis of GBM is mandatory to improve the overall survival of patients. A novel small non-coding RNA molecule, microRNA (miRNA), appears to represent one of the most attractive target molecules contributing to the pathogenesis of various types of tumors. Recent global analyses have revealed that several miRNAs are clinically implicated in GBM, with some reports indicating the association of miRNA dysregulation with acquired temozolomide (TMZ) resistance. More recent studies have revealed that miRNAs could play a role in cancer stem cell (CSC) properties, contributing to treatment resistance. In addition, greater impact might be expected from miRNA-targeted therapies based on tumor-derived exosomes that contain numerous functional miRNAs, which could be transferred between tumor cells and surrounding structures. Tumor-derived miRNAs are now considered to be a novel molecular mechanism promoting the progression of GBM. Establishment of miRNA-targeted therapies based on miRNA dysregulation of CSCs could provide effective therapeutic strategies for TMZ-resistant GBM. Recent progress has revealed that miRNAs are not only putative biological markers for diagnosis, but also one of the most promising targets for GBM treatment. Here in, we summarize the translational aspects of miRNAs in the diagnosis and treatment of GBM. Glioblastoma (GBM) is one of the most common and malignant primary brain tumors in adults . The recHomo sapiens miRNAs have been identified and registered in miRBase to date . In addition, miRNA expression profiling may yield more accurate classifications of human cancers than mRNA expression profiling , was recently identified and revealed to regulate a wide spectrum of gene expression in a post-transcriptional manner . More th to date . Primary to date . Express to date . Recent rofiling . The prein vivo study revealed that miR-21 plays a critical role in various steps of tumor progression .Dysregulated miRNAs, as identified by recent global studies for GBM, were summarized in our previous review . Each reBased on molecular pathological perspectives, GBM is a heterogeneous tumor. To elucidate novel therapeutic approaches, therefore, more precise stratification is necessary. Recent integrated genomic analyses have allowed molecular subclassification of GBM based on gene expression profiles . Two recRecent attempts at miRNA expression profiling may indicate the way toward more accurate classification of human cancers than mRNA expression profiling . Kim et We recently revealed that expressions of miR-196a and miR-196b are extremely high compared with other overexpressed miRNAs in GBM . FurtherSince the introduction of TMZ as standard chemotherapy, concomitant TMZ and radiotherapy have improved both progression-free and overall survival in patients with GBM . HoweverIn fact, recent miRNA studies have revealed that aberrant miRNA expression could affect chemosensitivity, and have also identified several miRNAs  associated with TMZ resistance . Recent in vitro in lung cancer cells and in vivo in C. elegans. Thereafter several reports revealed that miRNA dysregulation also affect the radiosensitivity of glioma cells .Recently, some miRNAs have been reported to contribute to CSC properties and cancer heterogeneity. Figure 1). Application of an antagonist of specific miRNAs (oncomiR), which would function as an oncogene, is one way of inhibiting oncogenic signaling pathways. Another is replacement therapy with mimics of miRNAs, to act as tumor suppressors. For both approaches, better delivery systems to target tissue remain under investigation. Multiple steps remain to achieve the targeted miRNA-based therapy. Inhibition of oncogenic molecules has been considered a more theoretically feasible approach. Considering replacement therapy, however, miRNA-based therapy could be more practical than conventional gene therapy, since miRNA is substantially smaller and more stable than protein-coding genes. Further elucidation of tumor suppressor miRNA thus has the potential to yield opportunities to develop replacement molecular therapies, which have not previously been considered as a realistic approach. In fact, recent research has facilitated the replacement of miRNAs for tumor suppressor miR-7, miR-128, and miR-34a over the inhibitory approach  to brains protected by the blood–brain barrier. Local delivery techniques could potentially improve the efficacy for GBM, since systematic metastasis is extremely rare in GBM compared with other types of tumor. Convection-enhanced delivery (CED) is one of the most promising local delivery techniques to improve the efficacy of recent treatments, including conventional chemotherapy, molecular-targeted therapy, and gene therapy . For furTumor-derived exosomes and secreted miRNA are novel and exciting targets for miRNA-based therapy. Recent investigations have revealed that exosomes secreted by tumor cells contain numerous functional miRNAs , which cAs a novel molecule, miRNA may contribute to TMZ resistance in GBM and could offer a crucial biomarker not only as a diagnostic marker, but also as a target for molecular therapies. Therapies based on miRNA could achieve modest changes for more global gene expression, and may prove more effective than current molecular-targeted therapies, which target single protein-coding genes within an oncogenic signaling pathway. Molecular-targeted therapy based on miRNA expression profiles in CSCs has the potential to allow development of more radical treatment strategies in the future. Further investigation of miRNA biology in GBM could provide novel insights for the development of efficient treatment strategies, especially for TMZ-resistant GBM. Furthermore, investigations into tumor-derived exosomes are providing some of the most promising approaches for creating novel strategies for the diagnosis and treatment of GBM.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.


Sarcopenia and dynapenia pose significant problems for the aged, especially as life expectancy rises in developed countries. Current therapies are marginally efficacious at best, and barriers to breakthroughs in treatment may result from currently employed model organisms. Here, we argue that the use of indeterminate-growing teleost fish in skeletal muscle aging research may lead to therapeutic advancements not possible with current mammalian models. Evidence from a comparative approach utilizing the subfamily Danioninae suggests that the indeterminate growth paradigm of many teleosts arises from adult muscle stem cells with greater proliferative capacity, even in spite of smaller progenitor populations. We hypothesize that paired-box transcription factors, Pax3/7, are involved with this enhanced self-renewal and that prolonged expression of these factors may allow some fish species to escape, or at least forestall, sarcopenia/dynapenia. Future research efforts should focus on the experimental validation of these genes as key factors in indeterminate growth, both in the context of muscle stem cell proliferation and in prevention of skeletal muscle senescence. As the world’s population grows past seven billion, the incidence of sarcopenia and dynapenia is expected to rise. In fact, nearly 87 million persons in the United States will be over the age of 65 by the year 2050 . This maCurrent strategies developed to combat sarcopenia and dynapenia allow for improved treatments and alternative approaches based on an increased understanding of these conditions. While clinicians have long relied on improved nutrition, specific types of exercise (whether that be simple increases in activity or targeted strength training), and management of comorbidities, there is much agreement that interventions at the level of the adult skeletal muscle stem cell, the myosatellite cell (MSC), are not only warranted, but badly needed . DespitePit1-/-) and Ames (Prop1-/-) mice  important to aging promotion or resistance  has been examined under diet or caloric restriction in several strains of mice . In addisistance . With resistance . HoweverWhile limited studies in mammals appear to indicate that smaller body size within a species may be correlated with increased lifespan , vertebrOf all the biological differences between rodents  and teleost fish, the most important may be the contrasting growth potentials of these two groups of animals. Laboratory rodents, like nearly all mammals and including humans, reach a definitive size following puberty; that is, they exhibit a characteristic growth plateau  and are Mus musculus) is augmented primarily by hypertrophy of existing myofibers in the postnatal period. Conversely, Oncorhynchus mykiss) skeletal muscle of both fiber types can undergo myofiber hypertrophy and hyperplasia, recruiting nascent myofibers well into the postlarval period without injury or trauma. Outside the salmonid clade, other fishes, namely cyprinids such as the common carp . Fast-glycolytic, type II myofibers constitute the bulk of the teleost myotome, with a small band of type I fibers running parallel to the lateral line . These aOryzias latipes; Danio rerio) and giant danio  and giant danio  are drastically different, with an obvious growth plateau being reached in the former. The larger, indeterminate giant danio, however, continues to grow without such an asymptote. Under strong growth promotion , these differences hold true, with the determinate-like zebrafish maintaining a growth plateau while the indeterminate giant danio is able to modulate its growth trajectory . The same appears to be true for the indeterminate giant danio , with each fish possessing 2.2 million MPCs . However, giant danios’ are much larger than their true Danio cousins (on the order of three times). Correcting for mass, 6.404 × 103 MPCs/mg-muscle reside in the fast-glycolytic epaxial myotome of each zebrafish while a mere 1.798 × 103/mg-muscle can be found in the larger giant danio. With respect to other members of the Danioninae subfamily, the trend is the same. The smallest species examined, the celestial pearl danio (Danio margaritatus), yields around 1.2 million MPCs per fish  or approximately 11000 MPCs/mg of skeletal muscle . While the celestial pearl danio is only one-tenth the size of its much larger cousin (the giant danio), its epaxial musculature holds more than six times as many MPCs. Interestingly, intermediate-sized danionins’  possess an intermediate number of MPCs . While giant danios are not true Danio, similar cell populations are found in the similarly sized mustached danio . Strikingly, the rainbow trout (Oncorhynchus mykiss) possesses the fewest MPCs, with 5.175 × 101 ± 2.566 × 101 MPCs/mg of skeletal muscle. Thus, it appears that larger fish have remarkably fewer MPCs and cell population size cannot account for the opposing growth paradigms. How then do fish accomplish lifetime growth in their musculature with such few MPCs? We hypothesize that enhanced self-renewal of adult stem cells  leads to the indeterminate growth paradigm, with subsequent differential fusion later in myogenesis in the case of skeletal muscle. This phenotype is likely linked to differential gene expression or pathway signaling, holding promise for aging research.Because upward of 60% of the mass of a teleost fish is constituted by skeletal muscle, we hypothesized that myogenic precursor cells (MPCs), the adult stem cells of skeletal muscle, play an integral role in the lifetime growth potential (or lack thereof) of danionin fishes and likely all teleost fish. Using a well-established protocol for the isolation of such cells, we determined that each “determinate-like” zebrafish, appears to hold approximately 2.2 million MPCs  and the indeterminate rainbow trout , direct comparison is highly confounded. Mouse MSCs are identified by Pax7 expression (+ MPCs (Where do murine MPCs (MSCs) fall on this spectrum? pression , with lapression . As discpression . Additio . This phenomenon is unlike that seen in mammals, as GH can only stimulate muscle hypertrophy to a maximal size specifically and does not stimulate overall body growth generally in adult mammals . As shown by Danio margaritatus, the smallest of the danionins examined , appear to be less sensitive to GH, as this cellular population is augmented by approximately 101% following GH administration. Similarly, the intermediate-sized fish such as the rosy danio (Danio roseus) and the pearl danio  are able to increase MPC numbers by 127 and 177%, respectively. Most interestingly, the MPCs of the indeterminate giant danio undergo the most cellular proliferation . These data, in tandem with those collected under steady-state conditions, highly suggest that phenotypes, not numbers, of teleost MPCs afford lifelong skeletal muscle growth, and thereby somatic growth, in these fishes. mammals . For lif guppies  do not uin vivo data of mammalian MSC behavior in response to GH are lacking, GH does not appear to promote MPC/myoblast proliferation but does enhance fusion, at least primary in vitro culture , under similar conditions  family have been definitively implicated in skeletal myogenesis  and likely involves a suite of traditional ogenesis . Specifiogenesis . Interesogenesis . In mammogenesis .Prima fascia, it appears that secondary myogenesis in mammals and mosaic hyperplasia in fish are analogous processes. The demonstrated role of Pax3 during murine embryonic development (but its widespread absence in MPCs of juvenile and adult origins) solicits questions about the role of Pax3 and Pax7 during piscine development and postlarval myogenesis. Pax7, the perennial marker of MPCs in mammals, plays a key role in the self-renewal of these cells , Pax7 transcripts appear to be upregulated during in vitro myogenesis (even in late-stage myoblasts), a finding that appears to contrast with that seen in mammals . Importantly, age does not appear to fetter growth trajectories in the indeterminate danionins  do exhibit drastic senescence and death following spawning, this phenotype is likely linked to the semelparity of these species and not indeterminate growth  leads to minimal aging (shown in red), a paradigm not seen in fishes with a growth plateau, where the inability to sustain growth results in eventual muscle wasting (sarcopenia). However, this hypothesis can only be tested using an unconfounded model system, one exemplified by the danionin fishes.The presence of a growth plateau in zebrafish and many mammals appears to be consistent with the marked senescence, particularly in skeletal muscle, seen in these species. In contrast, the vast majority of teleosts do not seem to undergo such a process, a phenotype that may be linked to their lifelong, non-asymptotic growth generally and their ability to recruit nascent myofibers proximately. The central role of Pax transcription factors in myogenesis and their likely function in the self-renewal and proliferation of myogenic progenitors of fish (among other vertebrates) makes them prime candidates for the study of sarcopenia evasion in indeterminate teleosts. As While the indeterminate rainbow trout has been utilized by fish biologists for decades, it has not received the attention of aging researchers, largely due to its size, somewhat difficult husbandry, and lack of genomic resources. Even as the rainbow trout genome sequence nears completion, we are unaware of any directly comparable species within the salmonid family. Capitalizing on the model organism status of the zebrafish, large, indeterminately growing danionins such as the giant and mustached danio hold much promise improving the efficacy of current sarcopenia/dynapenia treatments and advancing the discovery of new and innovative drug targets to combat these pervasive conditions, provided that the necessary husbandry and breeding protocols, life history, and senescence-related data are available.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.