Tropical dry forests (TDFs) are highly endangered tropical ecosystems being replaced by a complex mosaic of patches of different successional stages, agricultural fields and pasturelands. In this context, it is urgent to understand how taxa playing critical ecosystem roles respond to habitat modification. Because Phyllostomid bats provide important ecosystem services (e.g. facilitate gene flow among plant populations and promote forest regeneration), in this study we aimed to identify potential patterns on their response to TDF transformation in sites representing four different successional stages  in three Neotropical regions: México, Venezuela and Brazil. We evaluated bat occurrence at the species, ensemble (abundance) and assemblage level . We also evaluated how bat occurrence was modulated by the marked seasonality of TDFs. In general, we found high seasonal and regional specificities in phyllostomid occurrence, driven by specificities at species and guild levels. For example, highest frugivore abundance occurred in the early stage of the moistest TDF, while highest nectarivore abundance occurred in the same stage of the driest TDF. The high regional specificity of phyllostomid responses could arise from: (1) the distinctive environmental conditions of each region, (2) the specific behavior and ecological requirements of the regional bat species, (3) the composition, structure and phenological patterns of plant assemblages in the different stages, and (4) the regional landscape composition and configuration. We conclude that, in tropical seasonal environments, it is imperative to perform long-term studies considering seasonal variations in environmental conditions and plant phenology, as well as the role of landscape attributes. This approach will allow us to identify potential patterns in bat responses to habitat modification, which constitute an invaluable tool for not only bat biodiversity conservation but also for the conservation of the key ecological processes they provide. In the Neotropics, the natural landscape has been increasingly modified by human activities such as cattle raising and agriculture Solanum, Cecropia, Piper, Vismia) Bats are considered one of the key-stone groups in the Neotropics due to the ecological services they provide: seed dispersal, pollination, control of invertebrate and small vertebrate populations and recycling and translocation of nutrients and energy 2) One of the most endangered ecosystems within the Neotropics is the tropical dry forest (TDF), a preferred zone for agriculture and human settlements Tropical dry forests are characterized by a marked seasonality in the precipitation regime and a severe dry season (DS), which can last from three to eight months, depending on the latitudinal position (TDFs farthest from the equator present the longest DS) In general, tropical bats deal with seasonal fluctuations of key resources  and climate conditions  through behavioral and physiological adaptations. Examples of this are changes in diet breadth, type of food, food intake rate, patterns of habitat use, defense of feeding areas and migratory behavior sensu Fauth et al. The response of bats to seasonality provokes marked seasonal changes in their assemblages. Stoner In spite of the variable methodologies employed for studying bat response to habitat modification, some patterns emerge in the literature. For example, rare species with specialized diet and habitat requirements, such as gleaning insectivores and carnivores from the subfamily Phyllostominae, are more tightly associated with mature forest It is urgent to document patterns of phyllostomid response in Netropical dry forests as disturbed TDF areas continue increasing in extension and importance The main goal of our study was to identify and explain potential patterns of phyllostomid bat occurrence in patches of TDFs representing different degrees of vegetation development , which were defined by their time since abandonment by farmers. These patches represent an important element in natural landscapes affected by anthropogenic activities such as cattle raising and agriculture. In order to identify any potential pattern we documented phyllostomid response in three Neotropical regions: Mexico, Venezuela and Brazil.First, due to the marked seasonality in the precipitation regime that characterized the TDFs, we documented the seasonal changes on the phyllostomid assemblage attributes  at each sampling site. Then we compared the assemblages , ensembles (abundance) and species populations (abundance) occurring in the different successional stages, considering the phyllostomid response to seasonal changes observed in the first analysis. We also analyzed how the variation in vegetation structural complexity could explain the observed bat response.We expect to find two main patterns at the assemblage level that might further be linked with bat response at the ensemble or population levels. First, seasonal variations in phyllostomid assemblage composition and structure will occur as a consequence of the marked seasonality of TDFs. Specifically, we expect to find an increase in species diversity and bat abundance during the rainy season due to a higher availabity of trophic resources and shelter Bat captures and handling were in accordance with the laws of the Mexican, Venezuelan and Brazilian governments. In Mexico, we have the authorization of the Oficina de Fauna Silvestre (SGPA/DGVS Permit 3644 to KES). This study was also approved by the Secretaría de Medio Ambiente y Recursos Naturales (SEMARNAT), and the Consejo Nacional de Ciencia y Tecnología (CONACYT) from Mexico (Projects 2002-C01-0597 and CB-2005-51043). In Venezuela, we obtained the authorization of the Oficina Administrativa de Permisiones del MINAMB (Licencia de Caza con Fines Científicos 5136 to JAG). In Brazil, we have authorization from the Instituto Brasileiro do Meio Ambiente e dos Recursos Naturais Renováveis - IBAMA (Permit numbers 14654-1 and 14654-2) and from the Instituto Estadual de Florestas (IEF-MG).The study was performed in three regions: 1) the central western coast of Mexico, in and surrounding the Chamela-Cuixmala Biosphere Reserve (hereafter Mexico), wich is located in the state of Jalisco  These regions, with a marked seasonal rainfall pattern, delineate a gradient of precipitation. In Venezuela, average annual precipitation is 1469 mm, with 86% of the rainfall occurring between May–October In general, the landscape of the three regions consists of a mosaic of interdigitated forests and open areas where vegetation types are defined based on interactions of elevation, substrate and hydrology, being water availability the most relevant source of environmental heterogeneity for plant establishment and growth Agriculture and cattle raising are the most important economic activities in the three regions, but tourism is also important in Mexico and Venezuela. As a consequence of these human activities, large areas of these landscapes are covered by cattle ranches, agricultural fields and patches of secondary vegetation representing different successional stages.In each region we selected twelve sampling sites representing four successional stages , defined in terms of their time since abandonment by farmers : (1) pastures or initial stages, from P1 to P3, are sites used for cattle raising until the beginning of this study, (2) early successional stages, from E1 to E3, are sites from 3 to 5 years old, (3) intermediate successional stages, from I1 to I3, are sites from 8 to 12 years old in Mexico, 10 to 15 years old in Venezuela and 18 to 25 years old in Brazil, and (4) late successional stages, from L1 to L3, are sites of at least 50 years old. The sampling sites were selected based on the time elapsed since last major disturbance . This information was directly obtained from interviews with farmers and people working in the protected areas. Only sites that had been completely abandoned for an identified period of time were included. Most of the sites were abandoned when economic restrictions limited the farmer’s capacity to use them as agricultural or pasture fields.Other key characteristics for selecting each sampling site include: (1) their low slope (<25°), allowing the nets to be erected, (2) their distribution around the preserved forest , (3) their distance from the preserved forest, (4) their accessibility through trails and (5) their availability in each region. The distance from sites to the the preserved forest range from 1000 to 5000 m in Mexico, from 600 to 7000 m in Venezuela, and from 800 to 4000 m in Brazil. The distance among sampling sites range from 500 to 26000 m in Mexico, from 70 to 16650 m in Venezuela, and from 840 to 13500 m in Brazil.In general, pastures are dominated by non-native grasses and a few shrubs and treelets left standing for fencing and cattle shading. The early successional stage is characterized by an increasing presence of shrubs and the permanence of the non-native grasses and treelets. The height of the 10 tallest woody plants in this stage ranges from 4–7 m in Mexico, 12–16 m in Venezuela, and 5–7 m in Brazil. In the intermediate successional stage, the vegetation shows increments in height, basal area and species number with respect to the early stage. The height of the 10 tallest woody plants here ranges from 10–13 m in Mexico, 7–12 m in Venezuela, and 14–15 in Brazil. Finally, the late successional sites present, on average, the most structurally complex vegetation and the highest species richness 2 and the study period covered from June 2004 to August 2006. In Venezuela and Brazil we employed a set of ten 12-m mist nets; the total sampling area was 312 m2 and the study period spanned from July 2007 to April 2009 and from March 2007 to August 2009, respectively.Bat sampling was carried out using 2.6 m high mist nets set at ground level. In Mexico, we used a set of five mist nets– two 6-m, two 9-m and one 12-m long; the total sampling area was 109 mMist nets were located crossing natural or artificial corridors  representing potential flyways for bats. Distance among nets was never shorter than 30 m, and sampling was always performed during the first 5 hours after sunset, a period of time that coincides with the foraging peak for most phyllostomid bats Sampling efforts encompassed the rainy (RS) and dry (DS) seasons. Seasons were defined in accordance with the precipitation regime during the study period. The RS was considered to begin one month after the first rain, while the DS was considered to begin one month after the last rain During sampling, nets were checked every 30 min and all captured bats were stored in cloth bags. Pregnant females and juveniles were processed first and released. Bat species were identified based on the field guides of Linares Taxonomic designation of bat species follows Simmons Vegetation structure of each sampling site was characterized within a 0.10 ha (20 x 50 m) plot, considering all woody plants with a diameter at breast height (DBH) ≥5 cm In order to obtain a continuous synthetic variable summarizing sampling site variation in terms of vegetation structural complexity, we performed a principal component analysis (PCA) considering NI, NS and BA. The new variable  Sampling completeness per site was evaluated through the percentage of species captured in each site in relation to the site’s estimated species richness. Each season was considered separately. Species richness was estimated using the first-order jackknife estimator in EstimateS (v.8.2) We analyzed bat assemblage seasonal variations in terms of species composition, structure, species richness and abundance. For this purpose, in each site we compared RS versus DS phyllostomid assemblages.10 pi”  versus the species ranked from left to right according to their relative abundance. This method allows visualizing some assemblage attributes such as species richness (number of points), evenness (slope), number of rare species (tail of the curve) and species relative abundance (order of the species in the graph). Indeed, plotting the “log10 pi” instead of the total number of captured individuals per species, facilitates the comparison between curves differing in their total number of individuals.As a first step, in order to graphically represent assemblage attributes per site and per season, we built rank-abundance (dominance-diversity) graphs following Feinsinger 2 randomization test in the EcoSim software (v.7.72) In order to compare the species composition of RS and DS assemblages, we carried out an XPhyllostomid occurrence in the different sucesional stages was evaluated at the species, ensemble and assemblage-level. The RS and DS captures were also separately analyzed for this purpose. At the species and ensemble levels we used the capture rate  per site and per season as an indicator of local abundance. Only species and ensembles with at least 10 captured individuals in each season were analyzed. At the assemblage-level, we used as response variables the species richness estimated by the first-order jackknife estimator and four new synthetic variables reflecting the dissimilarities among the assemblages in terms of species (variables 1 and 2) and guild composition (variables 3 and 4). These synthetic variables were obtained by mapping, through a non-metric multidimensional scaling ordination (NMDS) Desmodus rotundus.The Bray-Curtis measure of distance allows the comparison of assemblages in terms of species/guilds presence and abundance We assessed the causal-explanatory relationships between all response variables and two explanatory variables, successional stage and vegetation structural complexity (scores of the PCA axis 1), through a hierarchical partitioning analysis Abundance data were modeled by using a Poisson error distribution with the log link function, while the response variables generated through NMDS were modeled using the Gaussian error distribution with the identity link function. When needed, the response variables were transformed in order to fit normality. In all cases the goodness of fit was based on log-likelihood.The pasture sites of Mexico had to be discarded from the analysis because of their low capture rates. The site L2 of Mexico was not considered in the hypothesis test evaluating the variation in phyllostomid assemblages in terms of species and guild composition, as no individuals were captured at this site during the DS. Zero values in capture data result in a meaningless value of the Bray-Curtis coefficient. The site P1 of Venezuela also was excluded from the analysis due to small sample size during the DS. Finally, the site L3 of Brazil was not considered in the analysis due to logistical problems in vegetation sampling.All statistical analyses described in this section were performed in R (v.2.11.1) Micronycteris microtis, Choeroniscus godmani, Musonycteris harrisoni, Centurio senex, Chiroderma salvini and Carollia sp. In Venezuela we conducted 94 sampling nights, 50 in the RS and 44 in the DS, allowing the capture of 996 phyllostomid individuals representing 30 species, 17 genera, 5 subfamilies and 6 broad guilds  and 3 species exclusively captured during the RS . Finally, in Brazil we performed 130 sampling nights, 46 during the RS and 84 during the DS, capturing 808 phyllostomid individuals classified in 19 species, 15 genera, 5 subfamilies and 6 broad guilds  and one species captured in the DS (Sturnira lilium).One hundred and forty-two sampling nights were performed in Mexico, 63 during the RS and 79 during the DS, leading to the capture of 606 phyllostomid bats representing 15 species, 11 genera, 5 subfamilies and 4 broad guilds . Nine ofd guilds . In Vened guilds . Due to Although the same 5 subfamilies were represented in the three study regions, in Mexico the best represented subfamily was Stenodermatinae, whereas in Venezuela and Brazil the best represented subfamily was Phyllostominae. . VenezueThe sampling effort used in the three regions was considered sufficient to characterize the phyllostomid assemblages occurring in each sampling site. Completeness reached 90% in all cases, ranging from 90 to 100% in Mexico, 95 to 100% in Venezuela and 91 to 100% in Brazil . NeverthArtibeus jamaicensis and Glossophaga soricina during the RS and by A. jamaicensis during the DS  during the DS. Species richness showed seasonal variation only in the site P3  and U. magnirostrum (during the DS)  . Neverth the DS) . This ismplexity . In contal sites .G. soricina,Regarding nectarivore abundance, the response in Mexico and Brazil was similar as well. In both regions, nectarivore abundance was significantly different among successional stages , being hLophostoma brasiliense, Trachops cirrhosus, Phylloderma stenops). However, the variation in their abundance was positively related to variations in vegetation structural complexity (during the DS)  . The uni the DS) .P. elongatus). Higher total abundance in these successional stages occurred during both seasons  were significantly higher in sites with higher vegetation structural complexity , as well as the lowest amount of available water across the year. The main sources of water around sampling sites consist of seasonally drying water bodies, such as temporary rivers and creeks. In this context, migration has been reported as one of the most important behavioral adaptations of the regional mammals to deal with water and food availability reductions during the DS Finally, the significant seasonal changes in species composition of the Venezuela assemblages, appear to be a distinctive feature of this region. In 2003, Aguirre et al. We found a high seasonal and regional level of specificity in phyllostomid occurrence across different successional stages. This specificity was related to the variation in environmental conditions and resource availability, as well as to particularities in the phyllostomid response at species and guild levels.Annona, Cecropia and Ficus are found in the Venezuela early successional sites . Chiropterochoric species are common in early succession of tropical wet and rainy forests Cecropia, Miconia, and Vismia accounted for 87% of the stems present in an area abandoned after three years of slash and burn agriculture The specificity of phyllostomid response to habitat change associated with succession was related to the contrasting ecological requirements of bat species and guilds. For example, frugivore abundance was higher in the early stage at Venezuela, but it did not show a marked difference among successional stages in Mexico or Brazil. The pattern observed in Venezuela, which is the region with the highest average annual precipitation (1469 mm) G. soricina). This is likely related to (1) the capacity of the most abundant nectarivores  to forage and exploit resources in areas where vegetation has a simple structure Acacia and CordiaRegarding nectarivorous bats, we found a similar response in Mexico and Brazil. In both regions the early successional stage, characterized by the presence of shrubs and some non-native grasses, showed a significantly higher nectarivore abundance at both the ensemble and species level . In Venezuela, the early successional sites presented a structurally complex vegetation as a consequence of their specific land-use history. When farmers cleared these sites, they left several remnant trees favoring a more complex vegetation structure. In adittion, two of the three sites representing this stage are close to one body of water (100 m far from the Laguna Grande lagoon), which attracts more prey used by bats such as insects, frogs, and other small vertebrates. The combination of these conditions could explain why these species were associated with early successional sites.Contrary to our expectations, the occurrence of gleaning insectivores did not differ among successional stages in the two regions in which they were analyzed (Venezuela and Brazil). Gleaning insectivore occurrence appears to be more tightly associated with variations in vegetation structural complexity as found in Venezuela . This caD. rotundus in anthropogenic tropical landscapes. Differences in the distribution and coverage of riparian vegetation around the sampling sites can also be influencing sanguivore occurrence. Riparian vegetation may affect sanguivore distribution in anthropogenic landscapes Omnivorous and sanguivorous bat occurrence in the different successional stages showed a high variability among regions. In the case of omnivores, this variability may be associated with the high diversity of food resources they use Micronycteris microtis), presented the highest differentiation in assemblage species and guild composition among successional stages.In contrast to our prediction, the region with the highest proportion of Phyllostominae (Venezuela) did not show differences among successional stages in relation to assemblage species and guild composition. On the contrary, the region with the poorest representation of Phyllostominae  In Mexico however, the occurrence of several species appears to be determined by successional stage. This is the case of the three most abundant nectarivores, which occur in higher abundance in the early stage , as wellIn relation to phyllostomid species richness, no consistent patterns were detected among the study regions. Whereas in Mexico none of the explanatory variables were significantly related to the variations in species richness, in Venezuela this parameter was explained by successional stage and in Brazil it was explained by vegetation structural complexity. These differences among the regions must be due to inter-regional variations in other non-measured factors likely related to attributes of the landscape surrounding the sampling sites.C. salvini, C. senex) occur In the case of Mexico, we detected high intra-successional stage variation in assemblage species richness. This variation was not explained by differences in vegetation structural complexity among sites. The late successional site, L2, for example, is one of the most preserved and structurally complex sites where rare species mainly associated with preserved forests  to a landscape scale. Future studies should include the characterization of landscape attributes (composition and configuration) as they appear to greatly influence the occurrence of vagile species in a particular area In general, phyllostomid response to habitat change in TDFs showed a high level of regional specificity. This response also showed a marked seasonal specificity as most bat responses were season specific. Climate distinctiveness, the specific ecological requirements and behavior of bat species in each region, the composition and structure of plant assemblages associated with different successional stages, as well as the specific landscape composition and configuration within each region, constituted important sources of variation precluding the detection of clear patterns in this Neotropical ecosystem.Based on our findings, we conclude that, in tropical seasonal environments, it is imperative to account for seasonal variations in environmental conditions and in the abundance and diversity of resources . This will allow us to understand seasonal dynamics in the use of space by phyllostomid bats, especially in those regions suffering from severe forest conversion Finally, findings such as the high inter-annual rate of species turnover in the studied assemblages, indicate that long-term studies are crucial to accurately characterize the phyllostomid assemblages and to identify the potential patterns in their response to habitat modification. The identification of such patterns would constitute an invaluable tool for the preservation of bat biodiversity and the key ecological processes they perform in transformed landscapes. After all “To do science is to search for repeated patterns” Figure S1Sampling site scores on PCA axis 1 reflecting vegetation structural complexity in the three study regions. Study regions: Chamela-Cuixmala Biosphere Reserve (black bars), Unidad de Producción Socialista Agropecuaria Piñero (gray bars) and Mata Seca State Park (white bars). Sampling sites representing different successional stages are: pastures (from P1 to P3), early (from E1 to E3), intermediate (from I1 to I3) and late stage (from L1 to L3).(TIF)Click here for additional data file.Figure S2Percentage of total species represented by each subfamily (A) and broad guild (B). Study regions: Chamela Cuixmala Biosphere Reserve in Mexico (Mexico), Unidad de Producción Socialista Agropecuaria Piñero in Venezuela (Venezuela), and Mata Seca State Park in Brazil (Brazil).(TIFF)Click here for additional data file.Table S1Number of individuals captured in each region during the rainy and the dry season (RS/DS).(DOC)Click here for additional data file.Table S2Turnover rate in species composition between consecutive sampling years for each region.(DOC)Click here for additional data file.Table S3Seasonal percentage of variation in population, ensemble and assemblage-level parameters associated with the variation of habitat attributes.(DOC)Click here for additional data file.Result S1Rank-abundance curves of the sampled phyllostomid assemblages.(DOC)Click here for additional data file.Result S2Average values and 95% confidence intervals of the response variables significantly differing among successional stages/seasons.(DOC)Click here for additional data file.Result S3Non-metric multidimensional scaling ordinations of sampling sites based on phyllostomid guild composition.(DOC)Click here for additional data file.Result S4Non-metric multidimensional scaling ordinations of sampling sites based on phyllostomid species composition.(DOC)Click here for additional data file.


In this review, we focus on CA3 neuronal migration disorders in the rodent. We begin by introducing the main steps of hippocampal development, and we summarize characteristic hippocampal malformations in human. We then describe various mouse mutants showing structural hippocampal defects. Notably, genes identified in human cortical neuronal migration disorders consistently give rise to a CA3 phenotype when mutated in the mouse. We successively describe their molecular, physiological and behavioral phenotypes that together contribute to a better understanding of CA3-dependent functions. We finally discuss potential factors underlying the CA3 vulnerability revealed by these mouse mutants and that may also contribute to other human neurological and psychiatric disorders. The development of the rodent hippocampus in the medial telencephalon starts in mid-embryogenesis, as factors are secreted from the cortical hem to induce, specify and amplify the adjacent neuroepithelium to produce cortical tissue  and neurons , with the CA1 formed before the CA3 region. Studies in the rodent show that the migration time was shorter for CA1 pyramidal cells (4 days) than CA3 (5 days), although migration to both these regions is slower than cortical neurons migrating in the neocortex + and reelin+, each with distinct properties  structures, or proteins linked to MTs, such as Microtubule Associated Proteins (MAPs) or MT motors. They regulate different aspects of saltatory cellular migration movements such as the elongation of the leading process or nuclear translocation. Some of these regulators, which are part of a generic program that commonly regulates neuronal migration in different cerebral regions such as the cortex, the cerebellum or the hippocampus, are also tightly regulated by region-specific cell to cell signaling.tubulin-alpha1a (Tuba1a) presents a severe fragmentation of the CA layers, including the CA3 region  mutants show no obvious hippocampal abnormalities  MAP . Cdk5 mediates phosphorylation of Neurofilament proteins, Map1b, Map2 as well as the MAP Tau. Genetic alteration of its expression (or its activator p35) revealed its important function in neuronal migration since the mutation generates a lack of a confined layer of pyramidal neurons in CA regions . While Rptp-α mouse mutants present neuronal migration defects in CA regions, the primary cause of these defects is still unclear. Rptp-α has been shown to be important in the formation of apical dendrites  have also confirmed the importance of the integrity of the glial scaffold to provide the appropriate substrate for neuronal migration. Indeed, in these mutants the glial fibers originating in the ammonic neuroepithelium may fail to mature, compromising severely the development of the hippocampal structure, especially in the DG, and potentially also CA3 subregions  a DNA alkylating agent , a gradient of severity is observed at the functional and behavioral levels that parallels the gradient of severity that is observed at the cellular level. Consistent with an extensive neuronal disorganization in both the neocortex and hippocampus, reeler mice exhibit severe motor, behavioral, and emotional impairments , layers. In addition, intracellular recordings, biocytin filling, as well as multi-electrode recordings showed that both layers of CA3 KO pyramidal cells exhibited an altered dendritic form and were more excitable than their WT counterparts , have a CA3 lamination defect as a common, and the most obvious, feature , it seems clear that CA3 cell migration is more complex than CA1. CA3 cells, especially in CA3b and c regions, have to migrate curved routes, which might involve several modes of migration, and particular features of radial glial cells that provide a cellular substrate. CA3 cell migration could hence require extra molecular and cellular pathways compared to CA1. The genes we mention in this review such as Dcx-KO postnatal hippocampus  was increased. IPSCs recorded in CA1 cells were also found to be increased  or CA1 (Lis1 mutants).Concerning CA3-dependant cognitive function, it seems that it may be remarkably preserved in the Dcx and Lis1 mutants, although defects in other cell types , and in different hippocampal  and/or other brain regions  are very likely to also contribute to such a phenotype. Identifying the origins of hyperexcitability remains a complex subject, as does distinguishing between causative and neuroprotective mechanisms. Cataloguing the different mutants available for study and focusing on the most restricted phenotypes may help dissect out these pathogenic and pathophysiological mechanisms.CA3 deficits may be correlated with hyperexcitability and epilepsy, e.g., These fundamental studies concerning rodent models thus contribute to deepen our understanding of basic genetic and cellular mechanisms underlying lissencephaly and related disorders. They also shed light on specific CA3 molecular and cellular features, including more complex curved routes and longer pausing steps during cell migration, as well as a reduced potential of genetic and functional redundancy, that may all contribute to a higher vulnerability of this region. This may indeed extend to other human neurological and psychiatric disorders, for example different types of epilepsy and schizophrenia. In the past decade, thanks to rodent studies, the identification of cellular mechanisms underlying CA3 hyperactivity, including increased glutamatergic input from the amygdala, leading to CA3 interneuron loss, has significantly contributed to our understanding of psychotic-related symptoms such as social phobia and hallucinations (Liddle et al., Richard Belvindrah, Marika Nosten-Bertrand, and Fiona Francis wrote the review.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.


Blunt chest trauma can lead to a variety of cardiac injuries, one of which is nonatherosclerotic myocardial infarction caused by intimal laceration and thrombotic process activation. Here we present a case of anterior myocardial infarction secondary to blunt trauma involving a kick to the chest. Blunt chest trauma can lead to a variety of different types of cardiac injury including: cardiac arrhythmias, myocardial muscle contusion, valvular disruption, coronary artery injury, cardiac chamber rupture, pericardial tamponade, and nonatherosclerotic myocardial infarction . The repA previously healthy 26-year-old Caucasian male presented to the emergency room (ER) with complaints of two-day duration of chest pain and shortness of breath after being kicked in the chest by his angry intoxicated girlfriend while he was lying in bed. The chest pain was initially pleuritic in nature, but by the next day changed in character to tightness in the chest, associated with shortness of breath. Q waves were present in V1–V3  demonstrated ST elevation in all precordial leads, most prominently in V2–V4. in V1–V3 . Given hThe coronary angiogram demonstrated a filling defect in both the proximal and mid portions of the left anterior descending (LAD) artery with distal TIMI 0 flow . In addiQ waves with continued depressed left ventricular ejection fraction of 15%.Patient remained in CICU for 5 days with discontinuation of the IABP on day 4. He was subsequently discharged on day 9 of hospitalization. Repeat EKG and echocardiogram demonstrated continued Trauma-related myocardial infarction is caused by a variety of pathologic causes including: intimal tear, plaque rupture associated thrombosis, coronary artery disease, coronary artery spasm, coronary artery dissection, and compression due to epicardial hematoma . The artDiagnosis of myocardial infarction posttrauma is often delayed secondary to comorbid conditions associated with the trauma. In a review, by Christensen et al, it was noted that only 9% of MI was detected in the first 24 hours and 13% in the first week .Treatment approach to myocardial infarction after blunt chest trauma is determined by the associated injuries secondary to the trauma. Treatment options include conservative approach, use of thrombolytics, which are limited by bleeding limits , and by The presentation of our patient differed from other reported cases of blunt chest trauma leading to non-atherosclerotic myocardial infarction and dissection in that a single kick to the chest led to two coronary vessel dissections, anterior myocardial infarction, and presumed myocardial stunning. The power generated by a single kick is significantly less than the impact associated with moving vehicles. In addition, the kick's force was not magnified by acceleration and deceleration forces typically associated with trauma associated myocardial infarctions . We pres


Influenza virus is a major human and animal pathogen causing seasonal epidemics and occasional pandemics in the human population that are associated with significant morbidity and mortality. Influenza A virus, a member of the orthomyxovirus family, contains an RNA genome with a coding capacity for a limited number of proteins. In addition to ensuring the structural integrity of virions, these viral proteins facilitate the replication of virus in the host cell. Consequently, viral proteins often evolve to perform multiple functions, the influenza A virus nuclear export protein (NEP)  being an emerging example. NEP was originally implicated in mediating the nuclear export of viral ribonucleoprotein (RNP) complexes, which are synthesized in the infected cell nucleus and are assembled into progeny virions at the cell membrane. However, since then, new and unexpected roles for NEP during the influenza virus life cycle have started to emerge. These recent studies have shown NEP to be involved in regulating the accumulation of viral genomic vRNA and antigenomic cRNA as well as viral mRNA synthesized by the viral RNA-dependent RNA polymerase. Subsequently, this regulation of viral RNA transcription and replication by NEP was shown to be an important factor in the adaptation of highly pathogenic avian H5N1 influenza viruses to the mammalian host. Unexpectedly, NEP has also been implicated in recruiting a cellular ATPase to the cell membrane to aid the efficient release of budding virions. Accordingly, NEP is proposed to play multiple biologically important roles during the influenza virus life cycle. Influenza viruses are a major contributor to disease and death in humans, and with their ability to cause yearly epidemics and occasional pandemics, they represent a considerable burden to healthcare systems globally. Influenza viruses are unpredictable, and novel strains, against which there is little or no preexisting immunity in the human population, can arise at any time. Currently the H5N1, H7N7, and H9N2 subtypes are considered to be particular threats, as these are prevalent in birds and can infect humans directly In order to initiate infection, the viral genome composed of eight single-stranded, negative-sense RNA segments must be introduced into a host cell. The viral genomic segments reside within the virion as viral ribonucleoprotein (vRNP) complexes bound to a heterotrimeric RNA-dependent RNA polymerase and the viral nucleoprotein (NP) During adaptation to replicate in new host species, influenza viruses must overcome the limited coding potential of a 15 kb genome. To this end, influenza viruses employ several strategies to increase genomic coding capacity, the most significant of which is encoding multiple polypeptides on the same genome segment. In this respect, unspliced and spliced mRNA transcripts of segments 7 and 8 are translated into distinct proteins In addition to extending the coding capacity of the viral genome by differential transcription and translation, influenza viruses also encode proteins that perform more than one function during virus infection. The best studied viral protein in this regard is the nonessential virulence factor NS1. This remarkably multifunctional protein has been shown to inhibit both interferon production and the activity of several interferon-induced genes, as well as inhibit the processing and nuclear export of host mRNA  and a protease-resistant C-terminal domain (amino acids 54–121), the crystal structure of which has been solved  [26]. AlThe highly structured C-terminal domain consists of two α-helices C1 (amino acids 64–85) and C2 (amino acids 94–115) that are connected by a short interhelical turn. The two α-helices are comparable in length and interact extensively, forming an almost perfectly antiparallel hairpin . The haiDuring influenza virus infection, incorporation of newly synthesised vRNPs into progeny virions is dependent on the export of vRNPs from the host cell nucleus. In this regard, nuclear export of vRNPs appears to be predominantly dependent on the cellular β-importin protein Crm1, which along with its cofactor RanGTP recognises a structurally conserved hydrophobic NES This evidence suggests that NEP serves a similar function to the HIV-1 Rev protein by acting as an adapter between vRNPs and the Crm1 export machinery. In this model for vRNP nuclear export , Crm1 reAlthough a plausible model for vRNP nuclear export has been demonstrated, several studies have called into question the role of NEP as the principal arbiter in this process. In this respect, it has been repeatedly noted that NEP and M1 do not colocalise with vRNPs, as would be expected if this was the sole mechanism for exporting viral genome segments from the nucleus In addition to the extensively studied roles of influenza virus-encoded proteins in vRNP nuclear export, several cellular factors have been proposed to contribute to this process. Perhaps the most interesting of these findings is that inhibition of the (mitogen-activated protein kinase) MAPK signalling cascade leads to impaired nuclear export of vRNPs by interfering directly with NEP-mediated export These observations indicate that there is the potential for considerable interplay between viral proteins and several distinct cellular factors during the nuclear export of vRNPs. Consequently, there appears to be significant redundancy in the influenza virus nuclear export pathway.In addition to the much-studied role of NS2/NEP in vRNP export, several studies have alluded to a novel role for NEP during influenza virus replication. Although a biochemical mechanism has yet to be described, NEP appears to play a significant role in regulating the accumulation of influenza virus mRNA, cRNA, and vRNA. Moreover, this function of NEP has been demonstrated to play a critical role in the adaptation of some avian H5N1 influenza viruses to efficient replication in mammalian cells PA gene The first study to conclude that NEP could influence events other than the export of vRNPs demonstrated that a single point mutation, I32T, results in highly efficient production of defective interfering (DI) particles lacking an intact Although the role of NEP in the production of aberrant genomic replication products is intriguing, it sheds little light on the role of NEP during virus replication. Subsequently, however, NEP was demonstrated to inhibit reporter gene expression in a dose-dependent manner using an influenza virus mini-replicon system Recent studies have shown that, in addition to inhibiting viral genomic replication and transcription, low concentrations of NEP can stimulate the accumulation of influenza virus vRNA and cRNA Until recently, the biological significance of NEP-mediated regulation of viral RNA accumulation was unknown. However, a recent study has demonstrated that mutations within NEP were responsible for the adaptation of a highly pathogenic avian influenza virus, thereby enabling increased replication in mammalian cells In a recent study, a novel species of virally encoded RNA was implicated in regulating the switch from viral transcription to replication Although the mechanism for NEP-mediated regulation of transcription and replication requires further elucidation, these studies all suggest a role for NEP during influenza virus infection that is independent of vRNP export. In this respect, it is salient to consider that other negative-sense viruses encode proteins, other than the nucleocapsid components, capable of regulating transcription and replication of their respective viral genomes. In particular, the NS1, NS2, and M2-2 proteins of human respiratory syncytial virus down-regulate viral RNA transcription and replication In conclusion, NEP has a well-studied role as an adapter protein during Crm1-mediated export of influenza virus vRNP complexes from the nucleus of infected cells. In addition, recent studies have implicated NEP in controlling the accumulation of viral RNA species within the host cell, in a manner that is distinct from its vRNP export function. Although the mechanism of this novel function remains unelucidated, it is tempting to suggest that NEP is a crucial factor, either independently or along with svRNA, in regulating viral transcription and replication.


SMN1) gene, and the diagnostic test demonstrates in most patients the homozygous deletion of the SMN1 gene, generally showing the absence of SMN1 exon 7. The test achieves up to 95% sensitivity and nearly 100% specificity. Differential diagnosis should be considered with other neuromuscular disorders which are not associated with increased CK manifesting as infantile hypotonia or as limb girdle weakness starting later in life.Spinal muscular atrophy (SMA) is an autosomal recessive neuromuscular disease characterized by degeneration of alpha motor neurons in the spinal cord, resulting in progressive proximal muscle weakness and paralysis. Estimated incidence is 1 in 6,000 to 1 in 10,000 live births and carrier frequency of 1/40-1/60. This disease is characterized by generalized muscle weakness and atrophy predominating in proximal limb muscles, and phenotype is classified into four grades of severity  based on age of onset and motor function achieved. This disease is caused by homozygous mutations of the survival motor neuron 1 . The role of follow-up coordination has to be managed by an expert in neuromuscular disorders and in SMA who is able to plan a multidisciplinary intervention that includes pulmonary, gastroenterology/nutrition, and orthopedic care. Prognosis depends on the phenotypic severity going from high mortality within the first year for SMA type 1 to no mortality for the chronic and later onset forms. Spinal muscular atrophy (SMA) is a severe neuromuscular disease characterized by degeneration of alpha motor neurons in the spinal cord, resulting in progressive proximal muscle weakness and paralysis. The disease was first described in the 1890s by Werdnig . The genSMA is the second most common fatal autosomal recessive disorder after cystic fibrosis, with an estimated incidence of 1 in 6,000 to 1 in 10,000 live births, with a carrier frequency of 1/40-1/60 ,6.SMA is clinical classified into four phenotypes on the basis of age of onset and motor function achieved  See tab.SMA type 1 (Werdnig-Hoffmann disease) is the most severe and common type, which accounts for about 50% of patients diagnosed with SMA. Classically infants with SMA type I have onset of clinical signs before 6 months of age, never acquire the ability to sit unsupported and, if no intervention is provided, generally do not survive beyond the first 2 years. These patients have profound hypotonia, symmetrical flaccid paralysis, and often no head control. Spontaneous motility is generally poor and antigravity movements of limbs are not typically observed. In the most severe forms decreased intrauterine movements suggest prenatal onset of the disease and present with severe weakness and joint contractures at birth and has been labeled SMN 0. Some of these children may show also congenital bone fractures and extremely thin ribs [hin ribs -11.Within SMA type I at least 3 clinical subgroups can be defined according to the severity of clinical signs: a) severe weakness since birth/neonatal period, head control is never achieved; b) onset of weakness after the neonatal period but generally within 2 months, head control is never achieved; c) onset of weakness after the neonatal period but head control is achieved. Some of these children may be able to sit with support .Clinically, all children with SMA type I show a combination of severe hypotonia and weakness, with sparing of the facial muscles, invariably associated with a typical respiratory pattern. The weakness is usually symmetrical and more proximal than distal, with lower limbs generally weaker than upper limbs. Deep tendon reflexes are absent or diminished but sensitivity is preserved.The spared diaphragm, combined with weakened intercostal muscles, results in paradoxical breathing. The involvement of bulbar motorneurons often give tongue fasciculation, poor suck and swallow with increasing swallowing and feeding difficulty over time. Aspiration pneumonia is an important cause of morbidity and mortality.In the last few years there has been increasing evidence that some cases with severe SMA type I  may have heart defects ,14, mostSMA type II is characterized by onset between 7 and 18 months of age. Patients achieve the ability to sit unsupported and some of them are able to acquire standing position, but they do not acquire the ability to walk independently. Deep tendon reflexes are absent and fine tremors of upper extremities are common. Joint contractures and kyphoscoliosis are very common and can occur in the first years of life in the more severe type II patients. Weak swallowing can be present but is not common [t common  while weSMA type III (Kugelberg-Welander disease) includes clinically heterogeneous patients. They typically reach all major motor milestones, as well as independent walking. However during infancy they develop proximal muscular weakness. Some might need wheelchair assistance in childhood, whereas others might continue to walk and live productive adult lives with minor muscular weakness. Patients who lose ambulation often develop scoliosis and other medical problems related to poor mobility such obesity and osteoporosis [oporosis -18. Concoporosis .SMA type IV has been added to this classification to describe those patients with adult onset (> 18 ys) and mild course. This group includes patients who are able to walk in adulthood and without respiratory and nutritional problems.Since all SMA types belong to a single spectrum and share the same etiology, patient selection for clinical trials is actually independent of the historical classification, and is essentially determined by the intervention characteristics and the choice of endpoints.SMN genes are present on chromosome 5q13: the telomeric or SMN1 gene, which is the spinal muscular atrophy- determining gene, and the centromeric or SMN2 gene.Two almost identical SMN2 differs from that of SMN1 by a single nucleotide (840C > T), which does not alter the aminoacidic sequence but results in alternative splicing of exon 7. Due to the alternative splicing of exon 7, SMN2 genes produce a reduced amount of full length transcripts (SMN-fl) and protein, and a variable amount of mRNA lacking exon 7  which give raise to a truncated and unstable protein [SMN1 due to deletion or gene conversion of SMN1 to SMN2 [SMN1 allele and subtle intragenic mutations. All patients, however, retain at least one copy of SMN2, generally 2-4. Loss of SMN1 is essential to the pathogenesis of SMA, while the severity of the disease is primarily related to the number of copies of SMN2. Most SMA type I patients have two copies of SMN2 [SMN2 copies are common in SMA type II, while type III and IV generally have three or four [The coding sequence of  protein . About 9 to SMN2 . About 3 of SMN2 , three S or four ,24.SMN genes encode for SMN protein which is ubiquitously expressed and localized in the cytoplasm and in the nucleus, and is particularly abundant in motor neurons of the spinal cord [nal cord . Within nal cord . Althougnal cord .SMN has been obtained in yeast, nematode, fly, zebrafish, and mouse. These models of spinal muscular atrophy have not only been fundamental for increasing knowledge about the molecular and cellular pathways of SMN, but also to better understand the mechanism(s) of disease, and to provide a platform from which high-throughput genetic and drug screens can be performed [SMN2+/+;Smn -/-) preclude detailed analysis of pathogenic mechanisms and preclinical drug testing [Animal models by disruption of erformed . However testing  However, testing .Two main hypothesis have been postulated to explain the pathogenesis of SMA: (a) SMN is involved in the biogenesis of small nuclear ribonucleoproteins (snRNPs) and in mRNA splicing: thus SMN reduction may determine a general perturbation in snRNP assembly (to which motor neurons may be more sensitive), and/or SMN complex is involved in the splicing of one or few transcripts with a key function in motor neurons; or (b) SMN has a motor neuron specific function, independent from snRNPs assembly, such as mRNA transport along the axon.Hypothesis (a) is supported by different experimental evidences: SMN protein is a part of a high molecular weight complex including at least eight other proteins, and it is necessary for proper assembly of Smith class core proteins in the Uridine-rich snRNPs (U snRNP). U snRNPs are the principal components of spliceosomes, the cellular particles that executes pre-mRNA splicing. Although SMN protein is expressed in all somatic cells, why motor neurons of the spinal cord are specifically vulnerable in spinal muscular atrophy is puzzling. Some studies suggest that SMN protein might play a key role in cellular functions unique to motor neurons -32.Also hypothesis (b) is supported by different lines of evidence: several studies suggest that SMN protein might sustain the survival of motor neurons by allowing normal axonal transport and maintaining the integrity of neuromuscular junctions. Low concentrations of SMN protein might be specifically detrimental to motor neurons due to the length of axons and to their unique interactions with skeletal muscles -40. FurtClinical features are highly suggestive for the diagnosis of SMA particularly in the severe variant of a floppy baby or weak child. The attentiveness and intellect is always good. The weakness is usually symmetrical and more proximal than distal; generally it is greater in the legs than in the arms. The severity of weakness correlates with the age of onset with delayed motor milestones according to clinical classification  confirms the diagnosis of SMA. The test achieves up to 95% sensitivity and nearly 100% specificity [The first level diagnostic test for a patient suspected to have SMA should be the search of cificity .SMN mutations should be pursued. Genetic tests now offer quick and reliable SMN1 gene copy number testing by using Multiplex ligation-dependent probe amplification (MLPA) or real time PCR. Semiquantitative assays improve diagnostic sensitivity up to 98% [SMN1 copy, it is mandatory to sequence the coding region of the undeleted allele to identify the second causative mutation, generally subtle sequence variations, including point mutations, insertions, and deletions. However, in about one third of patients with a typical clinical picture and a single SMN1 copy, the second mutation is not found in SMN1/SMN2 coding region. This finding is more common in type III SMA and might be due to the presence of deep intronic mutations, unidentified so far . Finally, sequence analysis of SMN1 gene is suggested also in those patients who have a typical clinical picture, 2 SMN1 copies, and are born to consanguineous parents or originate from genetic isolates. Indeed, rare patients homozygous for SMN1 subtle mutations have been occasionally reported [If the first level assay tests negative, further laboratory exams including creatine kinases dosage and electrophysiological tests such as electromyography (EMG), and nerve conduction study should be performed. If EMG suggests a motor neuron disease, then further testing for p to 98% ,44. If treported .SMN1copies, SMA diagnosis, related to SMN1 mutations is virtually excluded and other motor neuron disorders such as spinal muscular atrophy with respiratory distress (SMARD1), X-linked spinal muscular atrophy, distal SMA, and juvenile amyotrophic lateral sclerosis should be considered.Conversely, in a patient with 2 If the electrophysiological examination excludes a motor neuron disease the child should be reexamined and must receive additional diagnostic testing considering other disorders.In general, the most important differential diagnostic conditions for an infant presenting with hypotonia and/or weakness are congenital myopathies, i.e. myopathies with typical structural or ultrastructural features  on the muscle biopsy, congenital myotonic dystrophy, congenital myasthenic syndromes, metabolic myopathies, congenital disorders of the motor neuron and the peripheral nerve , as well as non-neuromuscular conditions including genetic syndromes such as, Prader-Willi syndrome, acute hypoxic ischemic encephalopathy, neonatal sepsis and dyskinetic or metabolic conditions.The most important tools to address these differential diagnostic possibilities beyond the clinical examination and a careful family history are CK determination (note however that the CK can be only moderately elevated in chronic forms of SMA), EMG/nerve conduction studies to discriminate neurogenic conditions and abnormalities of neuromuscular transmission, MRI of the brain, muscle biopsy, and specific genetic or metabolic testing,.SMN gene, that present with early weakness should be considered and are listed in table Other inherited motor neuron disorders, not caused by mutation of the SMN1 gene, the majority of carriers bear the heterozygous deletion of one SMN1 allele. As in the case of second level diagnostic test, carrier testing is based on semiquantitative real time PCR or MLPA. Since the sensitivity of the molecular test is 93-95% [Spinal muscular atrophy is one of the most common genetic disorders, with a carrier frequency of about 1/50, and direct carrier testing could be beneficial to community as screening test. Since the most common mutation found in patients is the homozygous absence of s 93-95% , it is iSMN1 copies in cis on one chromosome 5, may be carriers of rare subtle mutations, and the occurrence of extremely rare de-novo mutations cannot be ruled out. As (in the case of other) is true for carrier screening programs, SMA testing must be voluntary, performed in adults only, and upon informed consent and assurance of confidentiality [Thus it is imperative that individuals understand the limitations of the molecular testing: subjects who test negative for the search of heterozygous deletion may have two ntiality .In most cases, carrier testing is requested by siblings of patients or of parents of SMA children and are aimed at gaining information that may help with reproductive planning . In these cases, we suggest to test at risk individuals first and, in case of testing positive, to analyze also the partner. Thus in case of a request on carrier testing on siblings of an affected SMA infant, a detailed neurological examination should be done and consideration given doing the direct test to exclude SMA.th and 13th week of pregnancy. In all other instances, i.e. relatives of patients, carrier testing is sufficient to reduce markedly the risk of SMA for the offspring. In our opinion, prenatal diagnosis should be offered only when both partners test positive to the carrier screening; however, the clinical severity of a potentially affected foetus cannot be established a priori and the predictive power of SMN2 copy number assessment is not sufficient to establish an accurate prognosis. Indeed testing for SMN2 copy number in an affected fetus is problematic when there are 3 copies, as types I, II and III can all result in this setting and thus no prognosis can be established. Having a single copy is rare but is highly predictive of a severe type I baby with a very poor prognosis. A copy number of 2 is typical for a type I phenotype but could be a type II, again making any prognosis difficult. These considerations and facts have impact on neonatal screening, an argument that is growing with the progress in treatment prospective in SMA [Prenatal diagnosis should be offered to couples who have previously had a child affected with SMA (recurrence risk 25%); in these cases, antenatal screening by chorionic villi sampling can be carried out between the 11e in SMA . The pure in SMA -50, theie in SMA . TherefoA first consensus for standards of care of SMA has been achieved in recent years . BecauseRecommendations for respiratory assessment include evaluation of cough effectiveness, observation of breathing, and monitoring gas exchange. Respiratory muscle function tests are indirect measures of cough effectiveness and include peak cough flow, maximal inspiratory pressure, and maximal expiratory pressure. In case of a diagnosis of weak cough effectiveness cough-assist device and oral suction pump is advised. Overnight pulse oximetry with chart recording can be used to screen for nocturnal hypoxemia. Polysomnography with transcutaneous CO2 measurement are useful tools to assess sleep-related hypoventilation.When nocturnal hypoventilation is detected nocturnal noninvasive ventilation (NIV) must be started with bi-level positive pressure support. NIV can be used as a routine therapy  or as a palliative tool. A key goal is to prevent pediatric intensive care unit stays and avoid tracheotomy if possible. NIV should be the first choice to avoid tracheostomy.Additional therapies are medical or surgical gastroesophageal reflux disease management and nutritional support orally or via a gastrostomy.In SMA patients muscle weakness resulting in contracture formation, spinal deformity, limited mobility and activities of daily living, and increased risk of pain, osteopenia, and fractures. Infants should have appropriate evaluation for their presenting musculoskeletal and functional deficits. Goals of therapy and surgery depend on functional level and the family's wishes. Whenever possible, walking should be encouraged with appropriate assistive devices and orthotics. Hip subluxation is rarely painful, and there is a high risk of recurrence despite surgical correction. Spinal orthoses may provide postural support but do not prevent curve progression and may impair respiratory effort. Scoliosis surgery appears to benefit patients who survive beyond 2 years of age when curves are severe and progressive and should be performed while pulmonary function is adequate. Over the past few years newer surgical treatments have been developed for the management of severe scoliosis in skeletally immature patients prior to definitive spinal fusion. Growing-rods  or VertiActually no cure is available for SMA, and the pathogenesis of the disorder is not completely understood. In the last few years however many progresses in understanding the molecular basis of the disease has been made and different therapeutic approaches are developing .SMN2 gene expression [SMN2 pre-mRNA splicing, aimed at increasing SMN-fl levels, or to the enhancement of SMN2 promoter activity. An alternative therapeutic strategy is based on the use of antisense oligonucleotides (ASOs) targeting the 3' splice site (ss) of exon 8 [Several mechanisms have been targeted in SMA drug trials such as neuroprotective drugs to rescue motorneurons (as riluzole), creatine to improve energy metabolism, and albuterol for its anabolic properties and the molecular effect on pression . Prelimif exon 8  and inhif exon 8 . Similarf exon 8 .Following extensive high throughput screening of SMN promoter-activating compounds, novel quinazoline derivatives were recently developed, which not only increased SMN in vitro, but also improved the SMA phenotype in the SMNΔ7 mouse model ,63.in vitro. Successful read-through has also been achieved using different scaffolds with acceptable safety profiles as shown by PTC Therapeutics in a clinical trial with cystic fibrosis patients [An alternative strategy has been proposed by Mattis et al. (2006) : aminoglpatients .The group of compounds, histone deacetylase (HDAC) inhibitors, has shown promise in several models of neurodegeneration including SMA mouse models and patients . PositivSMN1 [cynomolgus macaque demonstrating that scAAV9 crosses the blood-brain barrier in a non-human primate and emphasizing the clinical potential of scAAV9 gene therapy for SMA [In addition to possible drug therapy, gene therapy approaches have been evaluated for SMA, using viral vectors to replace SMN1 . In a seSMN1 . In anotSMN1 . Fourt e for SMA .Adeno-associated virus (AAV) vectors have also been used to deliver ASOs to the central nervous system by intrathecal infusion. Passini et al (2011) have shown a very efficient transfer rate of oligounucleotides, with increased expression SMN-fl in mice models, and provided evidence that this route of administration has a higher efficiency than systemic delivery .Stem cell approaches offer promise as a cellular replacement strategy in the treatment of SMA and it is currently receiving considerable attention ,79. CellThe authors declare that they have no competing interests.AD and EB both wrote down the draft of this paper; EM reviewed the part of the Diagnosis and Management while FDT reviewed the part related to genetic counselling. All authors read and approved the final manuscript.


Nrf2), regulates the expression of antioxidant enzymes and proteins through the antioxidant response element. Nrf2 is an important component in antioxidant defenses in cardiovascular diseases such as atherosclerosis, hypertension, and heart failure. Nrf2 is also involved in protection against oxidant stress during the processes of ischemia-reperfusion injury and aging. However, evidence suggests that Nrf2 activity does not always lead to a positive outcome and may accelerate the pathogenesis of some cardiovascular diseases . The precise conditions under which Nrf2 acts to attenuate or stimulate cardiovascular disease processes are unclear. Further studies on the cellular environments related to cardiovascular diseases that influence Nrf2 pathways are required before Nrf2 can be considered a therapeutic target for the treatment of cardiovascular diseases.The cardiovascular system is susceptible to a group of diseases that are responsible for a larger proportion of morbidity and mortality than any other disease. Many cardiovascular diseases are associated with a failure of defenses against oxidative stress-induced cellular damage and/or death, leading to organ dysfunction. The pleiotropic transcription factor, nuclear factor-erythroid (NF-E) 2-related factor 2 ( Cardiovascular diseases contribute more to morbidity and mortality than any other group of diseases in the developed world . OxidatiNrf2 for mouse and rat), which is a member of the Cap “n” collar family of transcription factors . Nrf2 induces transcriptional activation of a number of ARE-bearing antioxidants, including NAD(P)H dehydrogenase (quinone 1) (NQO1), superoxide dismutases (SODs), and glutathione peroxidases (GPx). Many of the Nrf2 regulated enzymes are essential in the pathogenesis of cardiovascular diseases )Nrf2 in cardiopulmonary responses to oxidants, included in this issue . Cardiovascular and pulmonary function in conscious, freely moving rodents can be monitored in real time. Electrocardiogram, blood pressure, electroencephalogram, body temperature, and activity level waveforms can be recorded continuously in animals using implantable radio-telemetry transmitters, and pulmonary function can be recorded using whole body plethysmography. Recently, combination of these methods was used to investigate the genetic component to cardiopulmonary function in a wide range of commercially available strains of mice . In ordeNrf2 is a key component to cellular redox homeostasis in the attenuation of oxidative stress-associated pathological processes. In the cardiovascular system, patients with insufficient NRF2 levels in multiple tissues are likely susceptible to several adverse components of disease development. If Nrf2 expression is insufficient to protect against hypertension, then NRF2 is likely insufficient to protect against the resultant oxidative stress, atherosclerosis, and heart failure, highlighting the urgency for investigating Nrf2 further as a potential therapeutic target. Alternatively, there is evidence for increases in Nrf2 activity being detrimental to disease resistance and/or accelerating pathogenesis in cardiovascular diseases. Nrf2 shortly before initiating ischemia reperfusion may be beneficial in terms of cardiac function outcome, there is some evidence that chronic activation of Nrf2 could be detrimental to cardiac function. Therefore, further work is required to understand the role for Nrf2 in cardiovascular pathogenesis before Nrf2 can be seriously considered as a therapeutic target for treatment of cardiovascular diseases. This is especially important when considering the increasing prevalence of multiple comorbidities in aging populations [For example, while activating ulations .


Drosophila are currently one of the best model systems for understanding stem cell biology during normal development and during abnormal development of stem cell-derived brain tumors. In Drosophila brain development, the proliferative activity of neural stem cells called neuroblasts gives rise to both the optic lobe and the central brain ganglia, and asymmetric cell divisions are key features of this proliferation. The molecular mechanisms that underlie the asymmetric cell divisions by which these neuroblasts self-renew and generate lineages of differentiating progeny have been studied extensively and involve two major protein complexes, the apical complex which maintains polarity and controls spindle orientation and the basal complex which is comprised of cell fate determinants and their adaptors that are segregated into the differentiating daughter cells during mitosis. Recent molecular genetic work has established Drosophila neuroblasts as a model for neural stem cell-derived tumors in which perturbation of key molecular mechanisms that control neuroblast proliferation and the asymmetric segregation of cell fate determinants lead to brain tumor formation. Identification of novel candidate genes that control neuroblast self-renewal and differentiation as well as functional analysis of these genes in normal and tumorigenic conditions in a tissue-specific manner is now possible through genome-wide transgenic RNAi screens. These cellular and molecular findings in Drosophila are likely to provide valuable genetic links for analyzing mammalian neural stem cells and tumor biology.Neural stem cells in  Drosophila have become an excellent model for studying the cellular and molecular mechanisms that underlie stem cell function. Specifically, the neural stem cells in Drosophila, called neuroblasts for historical reasons, are currently one of the best and most extensively used model systems for understanding stem cell biology during normal development [Drosophila neural stem cells have also become useful for understanding the cellular and molecular basis of stem cell-derived brain tumors that arise due to loss of control of the stem cell divisions [Drosophila under normal conditions, present the current state of insight into the molecular elements that control the proliferative action of these neural stem cells during brain development, and discuss the alterations in the mechanisms of neural stem cell control that lead to overproliferation and brain tumor formation.Stem cells play a central role in the process of growth and development in multicellular organisms in which they ensure the generation of a large and diverse set of cell types as well as provide for the maintenance of tissue homeostasis –3. In reelopment , 5. Moreivisions , 7. In tDrosophila can be divided into the paired optic lobes and the central brain, and the neurons in both of these structures derive from neuroblasts. Of these two sets of neuroblasts, the neuroblasts that give rise to the central brain have been studied in much greater detail , which undergoes a limited number of repeated self-renewing asymmetric divisions, with each division resulting in one INP and one GMC [In addition to the majority of these so-called type I neuroblasts a smaller set of type II neuroblasts is located in the dorsoposterior and medioposterior region of each of the two central brain hemispheres (8 per hemisphere); these neuroblasts manifest a somewhat different proliferative activity that shows an interesting amplification of neural proliferation. Unlike the type I neuroblasts, in type II neuroblast proliferation the smaller daughter cell initiates expression of the proneural gene  one GMC –26  –48 whichit, Gαi –55, and it, Gαi –58. The it, Gαi –61. Droser cells , 62, 63.normally , 64  expression which sweeps across the neuroepithelium and leaves the asymmetrically dividing neuroblasts behind it [The molecular mechanisms that control the limited number of asymmetric proliferative divisions of the neuroblasts in the optic lobe are thought to be similar to those that operate in the INPs of type II neuroblast lineages in the central brain, however, this has not yet been studied in more detail. In contrast, a considerable amount of information is available on the molecular control of the neuroectoderm to neuroblast transformation occurring in the developing optic lobe. Initially and prior to neuroblast formation, the neuroectodermal cells are maintained in their expansive symmetrical division mode by Notch signaling, which also prevents their transformation to neuroblasts , 84. Howehind it , 88 gl, dlg, lethal (2) giant discs, and lethal (3) malignant brain tumor as potent tumor suppressor genes. Flies mutated for any of these tumor suppressor genes develop a tumor-like overproliferation in tissues such as the brain or the imaginal discs [Drosophila neuroblasts as an excellent model system for understanding the mechanisms that underlie neural stem cell-derived tumors [Classical genetic screens have identified a number of genes such as al discs , 89–93. d tumors , 5. InteDrosophila neuroblasts. Thus, mutations in any one of the key asymmetrically segregated cell-fate determinants Prospero, Numb, or Brat result in brain tumors, even if these mutations are restricted to individual neuroblast clones [prospero, numb, and brat mutant brain tissue form malignant tumors and metastases, and these tumors can be maintained through subsequent re-transplantation into hosts [Drosophila tumorigenesis can be relevant for understanding mammalian tumorigenesis as well.A firm link between dysregulated asymmetric cell division and brain tumor formation has been established for central brain neuroblasts . Indeed,t clones , 29–32. t clones . Interesto hosts , 94. In to hosts , Numb [9to hosts , and Proto hosts  have beel(3)mbt has recently been shown to result in optic lobe overgrowth [l(3)mbt mutants. Rather an overproliferation of the symmetrically dividing neuroepithelial cells during their expansion phase occurs in these mutants which in turn results in the generation of an uncontrolled number of optic lobe neuroblasts. At the molecular level, this unregulated overproliferation in the optic lobes of l(3)mbt mutants is caused, at least in part by derepression of the target genes of the SWH signaling pathway. Accordingly, experimental repression of SWH signaling or an increased expression of its downstream targets reproduces the massive proliferation of optic lobes similar to the l(3)mbt mutants [l(3)mbt mutants, the tumorigenic process is likely to involve the combined imbalance of several other signaling pathways like the Notch pathway [Drosophila. Thus, a different cascade of initiating events in larval brain neuroblasts and optic lobe neuroblasts finally leads to a similar outcome of overproliferating cells resulting in brain tumor formation [Tumorigenic overgrowth due to mutation in tumor suppressor genes also takes place in the optic lobes. For example, mutation of the tumor suppressor ergrowth –100. How pathway , 101–103 pathway , and oth pathway . Combineormation , 105.in vivo, where the immediate environment and the interactions with the surrounding niche are intact. This approach is eminently feasible in Drosophila, since genome-wide transgenic RNAi libraries are now available which allow for candidate gene functional analysis in a tissue-specific manner [Given the fundamental roles of the regulators of neural stem cell differentiation and maintenance that have been shown to operate in neuroblasts during normal brain development and during abnormal brain tumor formation, an in-depth analysis of their molecular mode of action and of their molecular interaction partners is of central importance. Several successful attempts have been made in the recent past, to identify novel candidate molecules involved in neural stem cell maintenance and differentiation at the genome-wide level using both microarray techniques and transcriptional target identification , 107. Hoc manner .Drosophila neuroblasts, transgenic RNAi targeted by the binary Gal4-UAS system was used to investigate the role of all known Drosophila genes in neuroblasts [Drosophila, the GAL4-UAS system [Drosophila brain. It is noteworthy that the dataset obtained from this RNAi screen is highly enriched for genes expressed in mammalian stem cells and thus is likely to provide valuable genetic links for analyzing mammalian stem cells and tumor biology [In a recent genome-wide study of self-renewal in roblasts , 109. InS system , 111 is Drosophila brain neuroblast model. A surprising aspect of this progress is the recent demonstration that key molecular control elements involved in asymmetric cell-fate determination in normal neuroblast lineages are also central elements in neuroblast-derived brain tumor formation. Further research in Drosophila and in other model systems is required to determine how the process of self-renewal and differentiation operates in normal neural stem cells and neural stem cell-derived cancer. Fortunately, the remarkable conservation of major transcriptional control and signaling pathways between flies and humans makes these studies of neural stem cells in Drosophila highly valuable for human stem cell biology. Thus, investigations in mammalian systems focused on the roles of those key factors for neural stem cell proliferation that have been identified in Drosophila are likely to be a gateway for a better understanding of many human cancers and further for developing therapeutic designs. Moreover, a sound understanding of the mechanisms underlying tumorigenic perturbations of neural stem cells is clearly a prerequisite for any potential development of neural stem cell-based therapy in humans.A great deal of progress has been made in understanding the cellular and molecular mechanisms that underlie proliferation and cell-fate decision in the


Epigenetic mechanisms play an extensive role in the development of liver cancer  associated with alcoholic liver disease (ALD) as well as in liver disease associated with other conditions. For example, epigenetic mechanisms, such as changes in the methylation and/or acetylation pattern of certain DNA regions or of the histone proteins around which the DNA is wrapped, contribute to the reversion of normal liver cells into progenitor and stem cells that can develop into HCC. Chronic exposure to beverage alcohol  can induce all of these epigenetic changes. Thus, ethanol metabolism results in the formation of compounds that can cause changes in DNA methylation and interfere with other components of the normal processes regulating DNA methylation. Alcohol exposure also can alter histone acetylation/deacetylation and methylation patterns through a variety of mechanisms and signaling pathways. Alcohol also acts indirectly on another molecule called toll-like receptor 4 (TLR4) that is a key component in a crucial regulatory pathway in the cells and whose dysregulation is involved in the development of HCC. Finally, alcohol use regulates an epigenetic mechanism involving small molecules called miRNAs that control transcriptional events and the expression of genes important to ALD. The molecular pathogenesis of liver cancer  is a multistep process that involves both genetic changes, such as chromosomal abnormalities and mutations of the DNA sequence , and epigenetic mechanisms, such as chemical modifications of the DNA and the histone proteins around which the DNA is wrapped to form the chromosomes, microRNA post-transcriptional regulators, and changes in various signaling pathways . This reAccording to some studies, ALD is the most common cause of HCC, accounting for approximately one-third of all HCC cases . ChronicAlcohol abuse also has synergistic effects with other risk factors for the development of HCC, such as infection with hepatitis B virus (HBV) or hepatitis C virus (HCV), diabetes, and obesity . For exaThe livers of patients who develop HCCs commonly are cirrhotic. Moreover, they often contain molecules  indicating that the cells undergo changes in their structure and function to a less specialized  state. These progenitor/stem cell markers mainly are found in the cirrhotic portion of the liver and in the regions where the HCC develops. These changes and markers have been observed in the livers of patients developing HCC associated with ALD, HBV, and HCV . The revOne step in the metabolism of beverage alcohol  in the liver is the oxidation of ethanol by a molecule called cytochrome P450 2E1 (CYP2E1). During this reaction, highly reactive, oxygen-containing molecules  are generated . ROS areEthanol also interferes with the metabolism of the amino acid methionine into a compound called S-adenosyl-methionine (SAMe) by several different methyl transferase reactions. SAMe, in turn, is needed as the methyl-group donor for many methylation reactions and is converted into S-adenosyl-homocysteine (SAH). Ethanol inhibits methionine adenosyl transferase, which converts methionine into SAMe, as well as enzymes that help regenerate methionine  . This wac-myc, c-Ha-ras, and c-K-ras, because the SAMe supplementation allowed for the methylation (and thus blockage) of the regulatory regions  for those genes. The potential role of SAMe in preventing tumor formation and survival also was supported by an in vitro study demonstrating that SAMe decreased the survival of a type of liver cell tumor Hepa 1–6 in a dose-dependent manner , or the addition of a molecule called ubiquitin . These modifications also can have an impact on tumor development. For example, the removal of acetyl groups  as well as hypermethylation is linked to the inactivation  of genes that can help repress tumor formation  and as a result may promote tumor development . Thus, some cancers exhibit CpG island hypermethylation in combination with multiple histone modifications, such as deacetylation of histones H3 and H4, methylation of histone H3K9, trimethylation of histone H3K27, and a loss of trimethylation of histone H3K4 .Alcohol exposure can alter histone acetylation and methylation patterns. Researchers have investigated these effects in rats that chronically were fed alcohol through a tube into the stomach . These studies identified several alterations in histone methylation and acetylation that correlated with the changes seen in HCCs. Thus, alcohol-treated animals showed increased acetylation of histone H3K18  and histThe increase in HAT p300 levels observed in chronically alcohol-fed rats also could lead to an increase in a signaling molecule called p21WAF1/C, p1 (p21) through several direct and indirect mechanismsThe induction of p21 by alcohol abuse may explain why HCC more often only occurs after the patient has stopped drinking. As mentioned above, alcohol consumption induces p21 expression, causing the cell-cycle arrest. After prolonged abstinence, this induction no longer persists in the liver, eliminating the cell cycle arrest and promoting cell multiplication and, thus, tumor formation.The role of p21 and p27 in HCC also is supported by studies showing that both proteins are overexpressed in alcoholic hepatitis and in rats chronically fed ethanol  For examThe levels of methylated histone H3K4 (H3K4me2), as well as histone H3K27 (H3K27me3), are increased in the nuclei of liver cells from rats fed ethanol intragastrically for 1 month , as demoWhereas histone acetylation is a highly dynamic process, modification of histones by methylation of one or more lysine amino acids  is thought to be a more lasting change that forms a “cellular memory.” Methylation is performed by enzymes known as methyl transferases, and the activity of these enzymes may be specific to certain histones. The enzymes that generate persistent methylation patterns and other histone modifications are known as histone code writers.The gene-silencing pathway mediated by H3K27 methylation is linked to the second major silencing pathway  via a deacetylase called SIRT 1 that is recruited by the PRC2 complex and contributes to gene silencing . SIRT 1 In individuals with HCC associated with ALD, focal progenitor cell/stem cell formation occurs both in portions of the liver that show cirrhosis and in the HCC cells as indicated by the expression of certain proteins  see ,. This rAnother molecule that is involved in the epigenetic mechanisms contributing to ALD-related HCC and which helps regulate the activity of Nanog is called toll-like receptor 4 (TLR4). Studies in a certain line of genetically modified mice  that were chronically fed alcohol found that TLR4 activation leads to up regulation of Nanog in stem cells . This TLRats fed ethanol intragastrically for 1 month had increased levels of TLR4 and another molecule called MyD88 in their livers. This effect could be prevented by feeding the animals SAMe together with the alcohol, which, as mentioned earlier, is required for methylation. These findings indicate that methylation can prevent the alcohol-induced changes in TLR4 and MyD88 levels . SimilarResearchers also have studied the TLR4-Nanog pathway in another line of genetically modified mice  that were fed alcohol; under these conditions, liver tumors form in the animals that contain cancer stem cells . During +/CD49f+ cells). CD49f enhances the cell’s ability to differentiate into different cell types  and maintains the cells’ stem-cell–like characteristics by directly controlling the regulatory molecules OCT4 and SOX2 (and SOX2 . In addiand SOX2 . This fiand SOX2 .MicroRNAs (miRNAs) are a class of small noncoding RNAs that, in general, negatively regulate gene expression at the posttranscriptional level. Each miRNA controls a specific set of target genes. miRNAs have been identified in various tumor types, including HCCs. miRNAs also are encoded by specific genes in the DNA. miRNA genes that harbor CpG islands can undergo methylation-mediated silencing, similar to many tumor suppressor genes. As a result, the miRNAs are not produced and therefore cannot inhibit the expression of their target genes. In one study examining the expression of 11 miRNA genes in HCCs, three of those genes were silenced  . For miRStudies have shown that alcohol use regulates miRNAs that control transcriptional events and the expression of genes important to ALD . Mice feALD is a major cause of HCC, which usually develops long after alcohol abuse has ceased and when cirrhosis has developed. This clinical pattern suggests that changes in epigenetic liver cellular memory occur that affect differentiation and cellular renewal, as well as the transformation to HCC. Progenitor hepatocytes develop during the cirrhotic process from normal cells through epigenetic mechanisms, such as changes in DNA hyper- or hypomethylation, histone acetylation and methylation, and epigenetic reprogramming. For example, oxidative DNA damage from ethanol-induced ROSs leads to loss of methylated DNA. Chronic ethanol feeding leads to altered methionine metabolism and reduced DNA methylation because the levels of the major methyl donor SAMe are lowered. This process can be prevented by feeding SAMe or another compound called betaine together with ethanol.Likewise, chronic ethanol feeding alters the methylation and acetylation of histones in the liver. Histone acetylation leads to upregulation of p21, causing cell cycle arrest and DNA damage. This, in turn, results in loss of DNA methylation, as demonstrated in experimental rat models as well as in human alcoholic hepatitis and HCCs. Histone H3K27me3, together with EZH2, regulates stem cell renewal and differentiation of progenitor stem cells in the liver. The balloon cells, which form MDBs in alcoholic hepatitis and HCCs, show a decrease in nuclear H3K27me3 and an increase in pEZH2 in the MDBs. This supports the role of MDB-forming cells as progenitor cells that give rise to HCC transformation. This concept is supported by findings that the MDB-forming cells also express proteins that are markers of embryonal stem cells . The transformation of these progenitor cells to HCC is driven by the TLR4 signaling pathway, which is upregulated by increases in LPS levels in the liver that result from alcohol abuse. This upregulation of the TLR4 pathway, which has been demonstrated in rats chronically fed ethanol, can be prevented by SAMe supplementation. These and other findings support the concept that TLR4 may be a protooncogene responsible for the transformation of progenitor cells into HCC in ALD as well as HCV infection.


The role of MRI in the management of breast carcinoma is rapidly evolving from its initial use for specific indications only to a more widespread use on all women with newly diagnosed early stage breast cancer. However, there are many concerns that such widespread use is premature since detailed correlation of MRI findings with the underlying histopathology of the breast lesions is still evolving and clear evidence for improvements in management and overall prognosis of breast cancer patients evaluated by breast MRI after their initial cancer diagnosis is lacking. In this paper, we would like to bring attention to a benign lesion that is frequently present on MRI-guided breast biopsies performed on suspicious MRI findings in the affected breast of patients with a new diagnosis of breast carcinoma. For patients with newly diagnosed breast carcinoma, evaluation of the extent of the disease in the breast is of paramount importance in planning appropriate surgical therapy. Magnetic resonance imaging (MRI) plays an ever increasing role in the evaluation of additional areas in the affected breast deemed suspicious but indeterminate by other radiologic modalities. Technical developments such as MRI with high spatial resolution, special breast coils, dynamic kinetic imaging techniques, and intravenous contrast agents contribute to enhanced diagnosis of breast abnormalities. While excitement about the role of this modality in improving the planning of surgical treatment of breast cancer patients is increasing –6, many Our study population consisted of 44 MRI-guided needle core breast biopsies performed on 40 patients with newly diagnosed breast carcinoma at Rush University Medical Center, Chicago, IL, USA between May 2007 and July 2008. Histologic findings of these biopsies were reviewed and recorded. Patient age ranged from 36 to 77 years (average: 52 years).Overall, 9/44 (20.4%) of our MRI-guided breast biopsies were malignant, 29/44 (66%) were benign, and 6/44 (13.6%) showed atypia . Of the During the last few years there has been a heightened interest in the application of magnetic resonance imaging (MRI) in the management of breast cancer. Currently, MRI is used as a supplemental tool to complement conventional methods of radiologic and ultrasonographic breast evaluation. A number of appropriate indications for the clinical use of MRI in breast cancer diagnosis and management include clarification of questionable findings on mammography, evaluation and accurate staging of breast tumors in dense breasts, accurate evaluation of specific subtypes of breast carcinomas such as infiltrating lobular carcinoma, assessment of response to preoperative chemotherapy, diagnosis of occult primary breast tumors presenting with axillary nodal involvement, and surveillance programs assessing high-risk patients such as breast cancer gene carriers or patients with a history of chest irradiation –6. However, as the use of MRI at the time of new diagnosis of early stage breast cancer is quickly becoming a new standard of care, there is heightened concern that routine use of MRI for preoperative staging may lead to more extensive surgery, while solid evidence for improvement of surgical management, improved rates of local control, or improved overall prognosis is lacking –12. In aIn this paper, we report that MRI-guided needle core biopsies of separate lesions in the affected breast of patients with newly diagnosed breast carcinoma show additional foci of malignancy in 20% of cases. A high percentage (66%) of these additional suspicious areas by MRI are benign by histologic examination. More specifically, MRI-guided needle core biopsies seem to target a characteristic complex multicystic lesion lined by apocrine metaplastic epithelium, in over one third of the cases, a lesion we called “cystic apocrine metaplasia.” Our findings suggest that MRI-guided core biopsies result in an important change of detection of additional foci of malignancy in a significant number of cases. In addition, MRI-directed needle core biopsies often target benign lesions with specific histopathologic characteristics, namely, a characteristic complex multicystic lesion lined by apocrine epithelium, the so-called “cystic apocrine metaplasia.” We suggest that awareness of the correlation of this benign lesion with abnormal MRI findings by radiologists will be helpful as they evaluate breast MRI studies of patients with newly diagnosed early stage breast carcinoma.Ongoing carefully controlled studies comparing the strengths and weaknesses of breast MRI to those of conventional breast imaging in different clinical scenarios, as well as detailed correlation of MRI findings to underlying histopathology of breast lesions, are urgently needed in order to clearly define diagnostic criteria for widespread MRI use.


Long-acting injectable (LAI) formulations of antipsychotics are valuable treatment alternatives for patients with psychotic disorders, and understanding their safe use is critical. Post-injection delirium/sedation syndrome (PDSS) has been reported following treatment with one atypical antipsychotic LAI. Clinical databases of risperidone LAI and paliperidone palmitate were explored to identify if cases of PDSS had been observed.No cases of PDSS were identified in 15 completed trials of 3,164 subjects  or the postmarketing safety database of risperidone LAI. Only one case of PDSS was identified among 10 completed trials  of paliperidone palmitate—that case having been reported in a patient randomized to treatment with placebo. Examination of these prospective databases finds no evidence that risperidone LAI and paliperidone palmitate are associated with PDSS and suggest that findings seen with another antipsychotic LAI are not generalizable. Long-acting injectable (LAI) formulations of antipsychotic agents offer advantages to the use of orally administered agents in patients with schizophrenia who have difficulties with compliance and are at risk for relapse . While t1) included the following steps:The clinical trial databases for 15 completed studies  and the postmarketing safety database for risperidone LAI, and from 10 completed clinical trials  of paliperidone palmitate were evaluated for reports of PDSS. A PDSS identification algorithm was created based upon literature descriptions of PDSS [Development of a summary list of sedation/somnolence events of interest (SSEs) from subjects who experienced at least 1 event coded to MedDRA preferred terms of sedation, somnolence, hypersomnia, lethargy, narcolepsy, or sudden onset of sleep at any time;Creation of a subset listing of subjects who experienced at least 1 severe SSE within 1 day of receiving an injection; and who experienced at least 1 of the following MedDRA events within 1 day of the injection associated with the severe SSE: cataplexy, coma, consciousness fluctuating, depressed level of consciousness, loss of consciousness, sopor, stupor, unresponsive to stimuli, any of the preferred terms under the MedDRA high level group term (HLGT) seizures, any of the terms within the standardized MedDRA query (SMQ) of extrapyramidal syndrome, gait disturbance, gait deviation, parkinsonian gait, tachycardia, sinus tachycardia, hypotension, orthostatic hypotension, diastolic hypotension, or any of the terms within the SMQ Torsades de Pointes; and finally;Performance of a manual review of all subjects identified after the second step in the algorithm, limited to those who were hospitalized or required prolonged hospitalization to manage the severe sedation/somnolence event.1summarizes the incidences of treatment-emergent SSEs identified in steps 1 to 3 of the algorithm. Examination of the clinical trial and post-marketing risperidone databases revealed no cases of treatment-emergent SSEs that met the algorithm criteria for PDSS. Although 244 (8%) risperidone- and 8 (2%) placebo-treated subjects had at least 1 SSE, only 1 case (risperidone-treated) occurred within 1 day of the injection and it was not associated with concurrent excessive SSE symptoms and therefore did not meet the criteria for a PDSS event.Table One case meeting all of the algorithm requirements for PDSS was identified in the review of the clinical trial paliperidone palmitate databases. This case occurred in a patient enrolled in a double-blind clinical trial who had been randomized to placebo treatment. The patient was a 39-year-old Asian female with a history of schizophrenia, mixed hyperlipidemia, obesity, and secondary parkinsonism. Within hours of her Study Day 1 administration of placebo, she experienced a generalized seizure followed by symptoms of drowsiness, urinary incontinence and post-ictal confusion (likely secondary to the seizure) and was hospitalized.Upper 95% confidence limits for the probability of a PDSS event, given no events in 115,000 risperidone LAI injections and no events in 33,906 paliperidone palmitate injections are 0.003% and 0.01%, respectively.No reports or signals of PDSS were identified in subjects treated with either risperidone LAI or paliperidone palmitate. Given the sample sizes explored, there is 95% confidence that the true probability of a PDSS event is less than 0.003% following risperidone LAI injections and less than 0.01% following paliperidone palmitate injections. PDSS has been proposed to occur as a result of systemic exposure to an LAI with high blood/plasma solubility. Neither risperidone LAI or paliperidone palmitate have high water solubility. Risperidone LAI is an aqueous suspension wherein the active drug substance is encapsulated in a microsphere of polylactide-co-glycolide polymer. After injection, a small amount of risperidone (<1%) is released by diffusion within 24 hours. The remaining drug is gradually released as the microsphere copolymer is hydrolyzed and result in a low and steady release of risperidone over a period of several weeks, with the majority being released during weeks 4 to 6 following injection . PaliperIn summary, these results suggest that risperidone LAI and paliperidone palmitate do not have measurable risk for post-injection delirium/sedation syndrome.