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Polyurethanes (PURs) are versatile polymers used in a wide variety of fields, such as the medical, automotive, textile, thermal insulation, and coating industries as well as many everyday objects. Many PURs have applications that require a long service life, sometimes with exposure to aggressive conditions. They can undergo different types of physicochemical and biological degradation, but they are not compostable, and many of them constitute persistent waste in the environment. Although both bacteria and fungi can be involved in the degradation of PURs, fungi are often the main biodegradation agents. The chemical structure of PURs determines their degree of biodegradation. Fungal biodegradation of PURs is linked to the production of enzymes, mainly esterases and proteases, alongside laccases, peroxidases, and tyrosinases, which can modify the structure of polyurethane compounds by forming carbonyl groups. The experimental analysis of the biodegradation of PUR can be carried out by bringing the polymer into contact with a mold in pure culture or with a microbial consortium. Then, global measurements can be taken, such as weight loss, tensile tests, or the ability of microorganisms to grow in the presence of PUR as the sole carbon source. The analysis of the chemical structure of the polymer and its degradation products after fungal growth can confirm biodegradation and specify the mechanism. The main avenues of future research are directed towards the development of fully biodegradable PURs and, on the contrary, towards the development of PURs that are more resistant to degradation phenomena, in particular biodegradation, for applications where the material is in contact with living organisms.

Acute liver failure and chronic liver disease are associated with a wide spectrum of neurological changes, of which the best known is hepatic encephalopathy (HE). Historically, hyperammonemia, causing astrocyte swelling and cerebral oedema, was considered the main etiological factor in the pathogenesis of cerebral dysfunction in patients with acute and/or chronic liver disease. However, recent studies demonstrated a key role of neuroinflammation in the development of neurological complications in this setting. Neuroinflammation is characterized by activation of microglial cells and brain secretion of pro-inflammatory cytokines, such as tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and IL-6, which alter neurotransmission, leading to cognitive and motor dysfunction. Changes in the gut microbiota resulting from liver disease play a crucial role in the pathogenesis of neuroinflammation. Dysbiosis and altered intestinal permeability, resulting in bacterial translocation and endotoxemia, are responsible for systemic inflammation, which can spread to brain tissue and trigger neuroinflammation. In addition, metabolites derived from the gut microbiota can act on the central nervous system and facilitate the development of neurological complications, exacerbating clinical manifestations. Thus, strategies aimed at modulating the gut microbiota may be effective therapeutic weapons. In this review, we summarize the current knowledge on the role of the gut–liver–brain axis in the pathogenesis of neurological dysfunction associated with liver disease, with a particular focus on neuroinflammation. In addition, we highlight emerging therapeutic approaches targeting the gut microbiota and inflammation in this clinical setting.

We employ UV/Vis Diffuse Reflectance spectroscopy directly coupled with a packed bed flow reactor to extract quantitative kinetic information. We use as a show‐case the CuII/CuI redox dynamics during the reduction half cycle of the NH3‐Selective Catalytic Reduction (SCR) on Cu‐CHA catalysts. Our measurements enable quantification of the fraction of oxidized Cu, reconstructed by Multivariate Curve Resolution (MCR) together with monitoring of the gas‐phase evolution during the reaction. These data both on the dynamics of the gas‐phase and of the active site oxidation state have been used to assess the reduction half cycle rate equation and estimate the rate constant. Our results in terms of reaction orders and kinetic constant are in line with previous findings in the literature. Overall, our results demonstrate that the combined analysis of the UV spectra and of the gas‐phase dynamics provides converging and unparalleled kinetic insight: this approach effectively resolves ambiguities concerning RHC kinetics and mechanism. More in general, this work provides evidence that operando spectroscopy can be used to extract quantitative kinetic information on catalytic cycles. [ABSTRACT FROM AUTHOR]

We previously identified a homozygous Alu insertion variant (Alu _Ins) in the 3′-untranslated region (3′-UTR) of SPINK1 as the cause of severe infantile isolated exocrine pancreatic insufficiency. Although we established that Alu _Ins leads to the complete loss of SPINK1 mRNA expression, the precise mechanisms remained elusive. Here, we aimed to elucidate these mechanisms through a hypothesis-driven approach. Initially, we speculated that, owing to its particular location, Alu _Ins could independently disrupt mRNA 3′ end formation and/or affect other post-transcriptional processes such as nuclear export and translation. However, employing a 3'-UTR luciferase reporter assay, Alu _Ins was found to result in only an ∼50% reduction in luciferase activity compared to wild type, which is insufficient to account for the severe pancreatic deficiency in the Alu _Ins homozygote. We then postulated that double-stranded RNA (dsRNA) structures formed between Alu elements, an upstream mechanism regulating gene expression, might be responsible. Using RepeatMasker, we identified two Alu elements within SPINK1 's third intron, both oriented oppositely to Alu _Ins. Through RNAfold predictions and full-length gene expression assays, we investigated orientation-dependent interactions between these Alu repeats. We provide compelling evidence to link the detrimental effect of Alu _Ins to extensive dsRNA structures formed between Alu _Ins and pre-existing intronic Alu sequences, including the restoration of SPINK1 mRNA expression by aligning all three Alu elements in the same orientation. Given the widespread presence of Alu elements in the human genome and the potential for new Alu insertions at almost any locus, our findings have important implications for detecting and interpreting Alu insertions in disease genes. It is well known that RNA secondary structures can influence splicing and that inverted Alu elements can form such structures. Here, we demonstrate that an Alu insertion variant causes a human genetic disease by creating extended double-stranded RNA structures with pre-existing Alu elements. [ABSTRACT FROM AUTHOR]

Objective: Cognitive and psychiatric symptoms are frequently reported after SARS-CoV-2 infection, but their interplay has been only partially explored. We investigated frequency and severity of psychiatric symptoms in patients with persistent cognitive complaints after COVID-19. Methods: We conducted a cross-sectional study. Neurologists assessed 101 patients reporting cognitive symptoms after COVID-19. Patients were invited to fill a screening battery with self-reported psychometric scales (Depression Anxiety Stress Scales-21, Impact of Event Scale-Revised, Insomnia Severity Index). Patients scoring above validated cut-offs in ≥1 scale were referred to psychiatrists who administered the Mini-International Neuropsychiatric Interview (M.I.N.I.), Hamilton Anxiety (HAM-A), and Hamilton Depression (HAM-D) rating scales and asked to complete the Personality Inventory for DSM-5-Brief Form (PID-5-BF). Results: Out of the 57 referred patients, 38 (64.4%) accepted to undergo the psychiatric examination. Among these, 18 (47.4%) were diagnosed with adjustment disorder (23.7%), anxiety disorder (10.5%), major depressive disorder (7.9%), and post-traumatic stress disorder (2.6%). Pharmacologic treatment before post-COVID condition (present in 12 patients, 31.6%) was associated with a score above cut-off on the HAM-A and HAM-D scales. A longer duration of untreated psychiatric illness after COVID-19 was associated with worse scores on the same scales. Patients with a higher PID-5-BF total score had a higher probability of receiving a psychiatric diagnosis. Conclusion: Almost half of patients with post-COVID-19 conditions reporting cognitive symptoms were found to suffer from a psychiatric condition after psychiatric evaluation. The application of a psychiatric screening in a population suffering from long-term effects of COVID-19 can lead to early diagnosis and timely treatment. [ABSTRACT FROM AUTHOR]

Nocturnal hypoxemic burden has been shown to be a robust, independent predictor of all-cause mortality in patients with heart failure and reduced ejection fraction (HFrEF) and to occur in a severe form even in patients with low or negligible frequency of respiratory events (apneas/hypopneas). This suggests the existence of two components of hypoxemic burden: one unrelated to respiratory events and the other related. The aim of this study was to characterize these two components and to evaluate their prognostic value. Nocturnal hypoxemic burden was assessed in a cohort of 280 patients with HFrEF by measuring the percentage of sleep with an oxygen saturation (SpO 2) <90% (T90), and the area of the SpO 2 curve below 90% (Area90). Both indices were also recalculated within the sleep segments associated with respiratory events (event-related component: T90 Eve , Area90 Eve) and outside these segments (nonspecific component: T90 Nspec , Area90 Nspec). The outcome of the survival analysis (Cox regression) was all-cause mortality. During a median follow-up of 60 months, 87 patients died. T90, Area90, and their components were significant in univariate analysis (P <.05 all). However, when these indices were adjusted for known risk factors, T90, T90 Nspec , Area90, and Area90 Nspec remained statistically significant (P =. 018, hazard ratio (HR)=1.12, 95%CI=(1.02, 1.23); P =. 007, HR=1.20, 95% CI = [1.05, 1.37]; P =.020, HR = 1.05, 95% CI = [1.01, 1.10]; P =.0006, HR = 1.15, 95% CI = [1.06, 1.25]), whereas T90 Eve and Area90 Eve did not (P =.27, P =.28). These results were internally validated using bootstrap resampling. By demonstrating a significant independent association of nonspecific hypoxemic burden with all-cause mortality, this study suggests that this component of total nocturnal hypoxemic burden may play an important prognostic role in patients with HFrEF. [Display omitted] [ABSTRACT FROM AUTHOR]

Human land use and climate change have profoundly impacted species distributions, with approximately a quarter of all known mammal species currently facing extinction threats. In this study, we modelled both present and future potential distributions of all 36 extant Canidae species to assess their responses to moderate and pessimistic future climatic scenarios. Additionally, we investigated the likelihood of canids experiencing evolutionary rescue, which could facilitate adaptation to climate change for certain species. We gathered species occurrence data for all extant canids and corresponding environmental variables for these locations. Our modelling results reveal that 32 species (89% of Canidae species) are projected to undergo range contractions owing to climate change, whereas four species (11% of canids) are expected to expand their ranges. Evolutionary analyses suggest that some canids might lack the capacity to adapt to the rapid pace of climate change, particularly Atelocynus microtis and Vulpes velox. Furthermore, our findings underscore the critical importance of incorporating variables related to proximity to water bodies to predict the future distributions of South American canids accurately. [ABSTRACT FROM AUTHOR]

An unexpected nitro group displacement during a nitro-Mannich reaction led to the one-pot formation of the octahydro-2H-pyrazino[1,2-a]pyrazine core, representing the shortest access to date to this pharmacologically relevant heterobicyclic system. A mechanistic hypothesis is suggested and supported by specific experiments and HRMS analysis of reaction mixtures. [ABSTRACT FROM AUTHOR]

Epstein-Barr virus (EBV) uses latency programs to colonize the memory B-cell reservoir, and each program is associated with human malignancies. However, knowledge remains incomplete of epigenetic mechanisms that maintain the highly restricted latency I program, present in memory and Burkitt lymphoma cells, in which EBNA1 is the only EBV-encoded protein expressed. Given increasing appreciation that higher order chromatin architecture is an important determinant of viral and host gene expression, we investigated roles of Wings Apart-Like Protein Homolog (WAPL), a host factor that unloads cohesin to control DNA loop size and that was discovered as an EBNA2-associated protein. WAPL knockout (KO) in Burkitt cells de-repressed LMP1 and LMP2A expression, but not other EBV oncogenes, to yield a viral program reminiscent of EBV latency II, which is rarely observed in B-cells. WAPL KO also increased LMP1/2A levels in latency III lymphoblastoid cells. WAPL KO altered EBV genome architecture, triggering formation of DNA loops between the LMP promoter region and the EBV origins of lytic replication (oriLyt). Hi-C analysis further demonstrated that WAPL KO reprogrammed EBV genomic DNA looping. LMP1 and LMP2A de-repression correlated with decreased histone repressive marks at their promoters. We propose that EBV coopts WAPL to negatively regulate latent membrane protein expression to maintain Burkitt latency I. Author summary: EBV is a highly prevalent herpesvirus etiologically linked to multiple lymphomas, gastric and nasopharyngeal carcinomas, and multiple sclerosis. EBV persists in the human host in B-cells that express a series of latency programs, each of which is observed in a distinct type of human lymphoma. The most restricted form of EBV latency, called latency I, is observed in memory cells and in most Burkitt lymphomas. In this state, EBNA1 is the only EBV-encoded protein expressed to facilitate infected cell immunoevasion. However, epigenetic mechanisms that repress expression of the other eight EBV-encoded latency proteins remain to be fully elucidated. We hypothesized that the host factor WAPL might have a role in restriction of EBV genes, as it is a major regulator of long-range DNA interactions by negatively regulating cohesin proteins that stabilize DNA loops, and WAPL was found in a yeast 2-hybrid screen for EBNA2-interacting host factors. Using CRISPR together with Hi-ChIP and Hi-C DNA architecture analyses, we uncovered WAPL roles in suppressing expression of LMP1 and LMP2A, which mimic signaling by CD40 and B-cell immunoglobulin receptors, respectively. These proteins are expressed together with EBNA1 in the latency II program. We demonstrate that WAPL KO changes EBV genomic architecture, including allowing the formation of DNA loops between the oriLyt enhancers and the LMP promoter regions. Collectively, our study suggests that WAPL reinforces Burkitt latency I by preventing the formation of DNA loops that may instead support the latency II program. [ABSTRACT FROM AUTHOR]

Objective: The main endpoint of the study was to evaluate if a daily intake of whey protein-based dietary supplement causes a worse response to levodopa in people with Parkinson's Disease (PWPD) Background: In PWPD, the competition between large neutral aminoacids and levodopa at intestinal absorption level may interfere with dopaminergic therapy's (DRT) effect; therefore, protein redistribution dietary regimen has been suggested. Many dietary supplementations are available to help people in balancing the protein intake and overcoming muscle mass loss. However, most of the products contain protein and could potentially affect levodopa action in PWPD. Methods: We performed a randomised single blind monocentric study on PWPD admitted in the rehabilitative unit for a 4-week multidisciplined intensive aerobic rehabilitation treatment. All patients received a standard protein redistribution dietary regimen plus a whey protein-based oral formula (N = 26) or Magnesium (N = 25) twice daily for 28 days. Neurological assessment and physical evaluation were conducted before (T0) and after (T1) rehabilitative treatment; DRT was recorded T0 and T1 as well. The delta of changes within groups in neurological (UPDRS III) and physical (TUG, 6 MW) evaluation scales was compared between groups. Results: Groups were comparable at baseline in clinical and demographic data; at T1, both groups showed a decrease in UPDRS III, TUG and 6 MWT and no differences between deltas were found. DRT remained stable in both groups. Conclusions: Our results show that whey protein supplementation does not interfere with DRT's efficacy and can be used in PWPD who need a protein supplementation without restrictions in intake hours. [ABSTRACT FROM AUTHOR]

Several coronaviruses infect humans, with three, including the SARS-CoV2, causing diseases. While coronaviruses are especially prone to induce pandemics, we know little about their evolutionary history, host-to-host transmissions, and biogeography. One of the difficulties lies in dating the origination of the family, a particularly challenging task for RNA viruses in general. Previous cophylogenetic tests of virus-host associations, including in the Coronaviridae family, have suggested a virus-host codiversification history stretching many millions of years. Here, we establish a framework for robustly testing scenarios of ancient origination and codiversification versus recent origination and diversification by host switches. Applied to coronaviruses and their mammalian hosts, our results support a scenario of recent origination of coronaviruses in bats and diversification by host switches, with preferential host switches within mammalian orders. Hotspots of coronavirus diversity, concentrated in East Asia and Europe, are consistent with this scenario of relatively recent origination and localized host switches. Spillovers from bats to other species are rare, but have the highest probability to be towards humans than to any other mammal species, implicating humans as the evolutionary intermediate host. The high host-switching rates within orders, as well as between humans, domesticated mammals, and non-flying wild mammals, indicates the potential for rapid additional spreading of coronaviruses across the world. Our results suggest that the evolutionary history of extant mammalian coronaviruses is recent, and that cases of long-term virus–host codiversification have been largely over-estimated. [ABSTRACT FROM AUTHOR]

The health benefits of nut consumption have been extensively demonstrated in observational studies and intervention trials. Besides the high nutritional value, countless evidences show that incorporating nuts into the diet may contribute to health promotion and prevention of certain diseases. Such benefits have been mostly and certainly attributed not only to their richness in healthy lipids (plentiful in unsaturated fatty acids), but also to the presence of a vast array of phytochemicals, such as polar lipids, squalene, phytosterols, tocochromanols, and polyphenolic compounds. Thus, many nut chemical compounds apply well to the designation "nutraceuticals," a broad umbrella term used to describe any food component that, in addition to the basic nutritional value, can contribute extra health benefits. This contribution analyses the general chemical profile of groundnut and common tree nuts (almond, walnut, cashew, hazelnut, pistachio, macadamia, pecan), focusing on lipid components and phytochemicals, with a view on their bioactive properties. Relevant scientific literature linking consumption of nuts, and/or some of their components, with ameliorative and/or preventive effects on selected diseases – such as cancer, cardiovascular, metabolic, and neurodegenerative pathologies – was also reviewed. In addition, the bioactive properties were analyzed in the light of known mechanistic frameworks. [ABSTRACT FROM AUTHOR]

Dispersion interactions are ubiquitous weak interactions that can play a role in many chemical events. Tailor-made catalysts and additives can lead to more selective reactions by properly exploiting dispersion interactions. Although radical-π dispersion interactions are known to have an important stabilizing role, this concept has been so far overlooked in synthetic photochemistry. We recently proved that similar dispersion interactions can play a profound impact on several reactions involving an energy transfer step. We present herein a study on the co-catalytic effect of tethered bi-naphthyl derivatives on the visible-light-promoted alkene-alkene [2 + 2] cycloaddition. A library of tethered bi-naphthyl derivatives was prepared in order to evaluate the impact of the tether on the efficiency of the prototypical [2 + 2] cycloaddition. The best performing additives showed a dramatic effect on the efficiency of the cyclization, and a rationalization of their relative efficiency was carried out through DFT modeling. The best co-catalyst allowed one to isolate desired products in good to excellent yields even employing several challenging substrates. These results offer new tools to devise optimized [2 + 2] photocycloaddition methods and provide valuable information for the design of organic co-catalyst that can boost photochemical reactions by exploiting dispersion interactions. [ABSTRACT FROM AUTHOR]

Trata-se de uma pesquisa documental descritiva, de abordagem qualitativa, com o objetivo geral de descrever a inclusão do tema Processo de Morte e Morrer nos Projetos Pedagógicos de Curso e Planos de Ensino dos cursos de graduação em Enfermagem da Região Sul do Brasil. Como objetivo de descrever a inclusão do tema Processo de Morte e Morrer nos Projetos Pedagógicos dos Cursos e Planos de Ensino dos cursos de graduação em Enfermagem da Região Sul do Brasil. O estudo teve como cenário 10 instituições que disponibilizaram material via e-mail e 09 que possuem os materiais disponíveis em domínio público. A coleta de dados foi realizada por meio de pesquisa em documentos no período de agosto a setembro de 2014. Para ordenação e organização dos dados, utilizou-se a análise de conteúdo. A proposta segue os preceitos éticos da Resolução n° 466/12 do Conselho Nacional de Saúde, foi avaliada e aprovada pelo Comitê de Ética em Pesquisa da Universidade Federal da Fronteira Sul. As informações, deram origem a três categorias relacionadas ao tema: Componente Curricular específico sobre o Processo de Morte e Morrer; Cuidados Paliativos e o manejo com pacientes terminais; Espiritualidade, Crenças Culturais e Religiosas sobre o PMM. Essas categorias mostram que o PMM é relacionado à religião, espiritualidade e cuidados paliativos nos CCRs. Outro fator relevante é que a abordagem da temática é escassa e utiliza metodologias de forma tecnicista e mecânica, quando o mesmo necessita de um olhar humanístico e subjetivo. Conclui-se que há necessidade de explorar essa temática que tem precária evolução. A reforma curricular é algo pontal para o avanço do PMM na formação do enfermeiro.

Introduction Mental health interventions for Italian (and European) prisoners with mental disorders remain a problematic issue, despite radical changes in general psychiatric care and a 2008 major government reform transferring mental health care in prison to the National Health Service. Indeed, according to the American Psychological Association, 64% of incarcerated individuals report mental health concerns. Objectives The aim of this study is to describe the mental health intervention model implemented since January 2020 for prisoners allocated in the Parma Penitentiary Institutes (PPI). This approach is specifically based on specialized, “person-centered” and “person-tailored” therapeutic-rehabilitation plans in line with psychiatric treatments usually provided in community mental health-care centers of the Parma Department of Mental Health. Methods All the processes and procedures included in the PPI intervention model were first carefully described, paying special attention to the service for newly admitted prisoners and each typology of specialized therapeutic-rehabilitation treatment potentially provided. Additionally, a preliminary descriptive process analysis of the first six months of clinical activity was also performed. Results Since January 2020, 178 individuals entered the PPI service for newly admitted prisoners. In total, 83 (46.7%) of them were engaged in the services of the PPI mental health-care team (35 with pathological addiction and 48 with mental disorders): 56 prisoners were offered an integrated mental health intervention and 27 exclusively an individual psychological or psychiatric treatment. Conclusions The results support the potential applicability of an integrated mental health intervention in prison, planning a person-tailored rehabilitation in close collaboration with the prisoners, their families and the local mental health/social services. Disclosure No significant relationships.

Introduction Personal Health Budget (PHB) has been provided to consumers with severe mental illness within a policy shift toward a person-tailored mental healthcare treatment based on individual unmet needs. PHB is an amount of money to support patient’s health and wellbeing needs, which is planned and agreed between patients and their local NHS team. It is not new money, but it may mean spending money differently so that patients can get the care that they need. However, evidence of beneficial effects of PHB is still scarce. Objectives The aim of this study was to provide preliminary data on clinical and social benefits of adding PHB to a standard pharmacotherapy in patients with severe mental illness across a 24-month follow-up period. Methods 137 individuals with severe mental illness (aged 18–50 years) were recruited in one of the adult mental health services of an Italian Department of Mental Health. They completed the Global Assessment of Functioning scale, the Health of the Nation Outcome Scale and the Brief Psychiatric Rating Scale. Friedman’s test for repeated measure was used to assess the longitudinal stability of functioning and clinical parameters. A linear regression analysis was also performed. Results A significant decrease in all GAF scale, HoNOS and BPRS scores along the 24 months of follow-up was observed. Regression analysis results specifically showed a relevant association between a PHB multiaxial intervention and the longitudinal reduction in BPRS ‘Negative Symptoms’ and HoNOS ‘Social Problems’ subscores. Conclusions Our findings support the useful implementation of a PHB approach for severe mental illness patients within the Italian mental health service network. Disclosure No significant relationships.

IntroductionNeurosurgical education should start during medical school to involve more students, favoring the recruitment of the most prepared and motivated ones and spreading this subject to the future medical generations. Despite multiple investigations, a dedicated educational plan does not exist. This study aims to assess the undergraduates' interests, needs, and perceptions of this subject.Materials and MethodsThe survey was structured to collect demographic data of the participants, and to explore their interest in neurosurgery, their consideration of its importance in medical school, their opinions about the role of this subject in medical education, their needs in this training, and, the usefulness of this subject for their future career.ResultsA total of 156 students participated in the survey. Interest in neurosurgery was shown by 76 (48.7%) participants, however, this subject was also perceived as intimidating by 86 (55.1%). Attending the first 2 years of medical school (p < 0.02), previous interest in neuroscience (p < 0.01), and in a surgical subject (p < 0.01) were the factors associated with a greater interest in this subject. Neurosurgery should be included in all students' education, according to 117 (75.0%) participants and practical operating room training should involve all students, according to 96 (61.5%). The most effective learning methods were considered internship (134, 85.9%), followed by participation in meetings or seminars (113, 72.4%). Online seminars were considered useful by 119 participants (76.3%). Neurosurgery was assessed as a potentially interesting career by 99 students (63.5%), who also considered that it can increase their preparation for other subjects (116, 74.4%).ConclusionsNeurosurgery was positively considered by medicals students, who, however, also perceived it as intimidating and hardly approachable. Demonstration that knowledge of neurosurgical concepts can improve their preparation also in general medical settings and, not only in the field of neuroscience, can be useful to promote their interest toward this subject. A combination of lectures and practical internships is considered an effective learning method, which can be fruitfully associated with new technologies.

BACKGROUND: Dengue is a major public health problem worldwide. Assessment of adaptive immunity is important to understanding immunopathology and to define correlates of protection against dengue virus (DENV). To enable global assessment of CD4+ T cell responses, we mapped HLA-DRB1-restricted DENV-specific CD4+ T cell epitopes in individuals previously exposed to DENV in the general population of the dengue-endemic region of Managua, Nicaragua. METHODS: HLA class II epitopes in the population of Managua were identified by an in vitro IFNγ ELISPOT assay. CD4+ T cells purified by magnetic bead negative selection were stimulated with HLA-matched epitope pools in the presence of autologous antigen-presenting cells, followed by pool deconvolution to identify specific epitopes. The epitopes identified in this study were combined with those previously identified in the DENV endemic region of Sri Lanka, to generate a megapool (MP) consisting of 180 peptides specifically designed to achieve balanced HLA and DENV serotype coverage. The DENV CD4MP180 was validated by intracellular cytokine staining assays. RESULTS: We detected responses directed against a total of 431 epitopes, representing all 4 DENV serotypes, restricted by 15 different HLA-DRB1 alleles. The responses were associated with a similar pattern of protein immunodominance, overall higher magnitude of responses, as compared to what was observed previously in the Sri Lanka region. Based on these epitope mapping studies, we designed a DENV CD4 MP180 with higher and more consistent coverage, which allowed the detection of CD4+ T cell DENV responses ex vivo in various cohorts of DENV exposed donors worldwide, including donors from Nicaragua, Brazil, Singapore, Sri Lanka, and U.S. domestic flavivirus-naïve subjects immunized with Tetravalent Dengue Live-Attenuated Vaccine (TV005). This broad reactivity reflects that the 21 HLA-DRB1 alleles analyzed in this and previous studies account for more than 80% of alleles present with a phenotypic frequency ≥5% worldwide, corresponding to 92% phenotypic coverage of the general population (i.e., 92% of individuals express at least one of these alleles). CONCLUSION: The DENV CD4 MP180 can be utilized to measure ex vivo responses to DENV irrespective of geographical location.

Assemblage-level studies of mean trait variation are common in macroecology. However, how phylogenetic relationships among species affect trait-based macroecological patterns is still unresolved. I used an approach based on variation partitioning analysis using environmental and phylogenetic lineage variation as predictors to investigate whether variation in mean trait values among Neotropical sigmodontine rodent communities is best explained by macroecological adaptation, biogeographical history, or joint effects of both – the latter resulting in phylogenetic niche conservatism (PNC) at the metacommunity scale. Metacommunity PNC best explained mean variation in body size and skull/mandible shape across assemblages, and the pattern of metacommunity PNC suggests that influence of environmental factors on mean trait variation relies heavily on spatial biogeographical clade sorting. This suggests that biogeographical lineage distribution should be taken into account in analyses seeking to correlate environmental variables with mean trait variation.