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The accessory protease transmembrane protease serine 2 (TMPRSS2) enhances severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) uptake into ACE2-expressing cells, although how increased entry impacts downstream viral and host processes remains unclear. To investigate this in more detail, we performed infection assays in engineered cells promoting ACE2-mediated entry with and without TMPRSS2 coexpression. Electron microscopy and inhibitor experiments indicated TMPRSS2-mediated cell entry was associated with increased virion internalization into endosomes, and partially dependent upon clathrin-mediated endocytosis. TMPRSS2 increased panvariant uptake efficiency and enhanced early rates of virus replication, transcription, and secretion, with variant-specific profiles observed. On the host side, transcriptional profiling confirmed the magnitude of infection-induced antiviral and proinflammatory responses were linked to uptake efficiency, with TMPRSS2-assisted entry boosting early antiviral responses. In addition, TMPRSS2-enhanced infections increased rates of cytopathology, apoptosis, and necrosis and modulated virus secretion kinetics in a variant-specific manner. On the virus side, convergent signatures of cell-uptake-dependent innate immune induction were recorded in viral genomes, manifesting as switches in dominant coupled Nsp3 residues whose frequencies were correlated to the magnitude of the cellular response to infection. Experimentally, we demonstrated that selected Nsp3 mutations conferred enhanced interferon antagonism. More broadly, we show that TMPRSS2 orthologues from evolutionarily diverse mammals facilitate panvariant enhancement of cell uptake. In summary, our study uncovers previously unreported associations, linking cell entry efficiency to innate immune activation kinetics, cell death rates, virus secretion dynamics, and convergent selection of viral mutations. These data expand our understanding of TMPRSS2's role in the SARS-CoV-2 life cycle and confirm its broader significance in zoonotic reservoirs and animal models.
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COVID-19 , Inmunidad Innata , SARS-CoV-2 , Serina Endopeptidasas , Internalización del Virus , SARS-CoV-2/inmunología , SARS-CoV-2/fisiología , SARS-CoV-2/metabolismo , Humanos , Serina Endopeptidasas/metabolismo , Serina Endopeptidasas/genética , COVID-19/virología , COVID-19/inmunología , COVID-19/metabolismo , Enzima Convertidora de Angiotensina 2/metabolismo , Enzima Convertidora de Angiotensina 2/genética , Replicación Viral , Animales , Endocitosis , Células HEK293 , Chlorocebus aethiops , CitologíaRESUMEN
Hepatitis C virus (HCV) infection progresses to chronicity in the majority of infected individuals. Its high intra-host genetic variability enables HCV to evade the continuous selection pressure exerted by the host, contributing to persistent infection. Utilizing a cell culture-adapted HCV population (p100pop) which exhibits increased replicative capacity in various liver cell lines, this study investigated virus and host determinants that underlie enhanced viral fitness. Characterization of a panel of molecular p100 clones revealed that cell culture adaptive mutations optimize a range of virus-host interactions, resulting in expanded cell tropism, altered dependence on the cellular co-factor micro-RNA 122 and increased rates of virus spread. On the host side, comparative transcriptional profiling of hepatoma cells infected either with p100pop or its progenitor virus revealed that enhanced replicative fitness correlated with activation of endoplasmic reticulum stress signaling and the unfolded protein response. In contrast, infection of primary human hepatocytes with p100pop led to a mild attenuation of virion production which correlated with a greater induction of cell-intrinsic antiviral defense responses. In summary, long-term passage experiments in cells where selective pressure from innate immunity is lacking improves multiple virus-host interactions, enhancing HCV replicative fitness. However, this study further indicates that HCV has evolved to replicate at low levels in primary human hepatocytes to minimize innate immune activation, highlighting that an optimal balance between replicative fitness and innate immune induction is key to establish persistence. IMPORTANCE: Hepatitis C virus (HCV) infection remains a global health burden with 58 million people currently chronically infected. However, the detailed molecular mechanisms that underly persistence are incompletely defined. We utilized a long-term cell culture-adapted HCV, exhibiting enhanced replicative fitness in different human liver cell lines, in order to identify molecular principles by which HCV optimizes its replication fitness. Our experimental data revealed that cell culture adaptive mutations confer changes in the host response and usage of various host factors. The latter allows functional flexibility at different stages of the viral replication cycle. However, increased replicative fitness resulted in an increased activation of the innate immune system, which likely poses boundary for functional variation in authentic hepatocytes, explaining the observed attenuation of the adapted virus population in primary hepatocytes.
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Aptitud Genética , Hepacivirus , Hepatocitos , Interacciones Microbiota-Huesped , Inmunidad Innata , Mutación , Humanos , Células Cultivadas , Estrés del Retículo Endoplásmico , Aptitud Genética/genética , Aptitud Genética/inmunología , Hepacivirus/genética , Hepacivirus/crecimiento & desarrollo , Hepacivirus/inmunología , Hepacivirus/fisiología , Hepatitis C/inmunología , Hepatitis C/virología , Hepatocitos/inmunología , Hepatocitos/virología , Interacciones Microbiota-Huesped/inmunología , MicroARNs/metabolismo , Pase Seriado , Respuesta de Proteína Desplegada , Tropismo Viral , Virión/crecimiento & desarrollo , Virión/metabolismo , Replicación Viral/genética , Replicación Viral/inmunologíaRESUMEN
BACKGROUND AND AIMS: HEV is estimated to be responsible for 70,000 deaths annually, yet therapy options remain limited. In the pursuit of effective antiviral therapies, targeting viral entry holds promise and has proven effective for other viruses. However, the precise mechanisms and host factors required during HEV entry remain unclear. Cellular proteases have emerged as host factors required for viral surface protein activation and productive cell entry by many viruses. Hence, we investigated the functional requirement and therapeutic potential of cellular protease during HEV infection. APPROACH AND RESULTS: Using our established HEV cell culture model and subgenomic HEV replicons, we found that blocking lysosomal cathepsins (CTS) with small molecule inhibitors impedes HEV infection without affecting replication. Most importantly, the pan-cathepsin inhibitor K11777 suppressed HEV infections with an EC 50 of ~0.02 nM. Inhibition by K11777, devoid of notable toxicity in hepatoma cells, was also observed in HepaRG and primary human hepatocytes. Furthermore, through time-of-addition and RNAscope experiments, we confirmed that HEV entry is blocked by inhibition of cathepsins. Cathepsin L (CTSL) knockout cells were less permissive to HEV, suggesting that CTSL is critical for HEV infection. Finally, we observed cleavage of the glycosylated ORF2 protein and virus particles by recombinant CTSL. CONCLUSIONS: In summary, our study highlights the pivotal role of lysosomal cathepsins, especially CTSL, in the HEV entry process. The profound anti-HEV efficacy of the pan-cathepsin inhibitor K11777, especially with its notable safety profile in primary cells, further underscores its potential as a therapeutic candidate.
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Programmed death-ligand 1 (PD-L1) is a key immune regulatory protein that interacts with programmed cell death protein 1 (PD-1), leading to T-cell suppression. Whilst this interaction is key in self-tolerance, cancer cells evade the immune system by overexpressing PD-L1. Inhibition of the PD-1/PD-L1 pathway with standard monoclonal antibodies has proven a highly effective cancer treatment; however, single domain antibodies (VHH) may offer numerous potential benefits. Here, we report the identification and characterization of a diverse panel of 16 novel VHHs specific to PD-L1. The panel of VHHs demonstrate affinities of 0.7 nM to 5.1 µM and were able to completely inhibit PD-1 binding to PD-L1. The binding site for each VHH on PD-L1 was determined using NMR chemical shift perturbation mapping and revealed a common binding surface encompassing the PD-1-binding site. Additionally, we solved crystal structures of two representative VHHs in complex with PD-L1, which revealed unique binding modes. Similar NMR experiments were used to identify the binding site of CD80 on PD-L1, which is another immune response regulatory element and interacts with PD-L1 localized on the same cell surface. CD80 and PD-1 were revealed to share a highly overlapping binding site on PD-L1, with the panel of VHHs identified expected to inhibit CD80 binding. Comparison of the CD80 and PD-1 binding sites on PD-L1 enabled the identification of a potential antibody binding region able to confer specificity for the inhibition of PD-1 binding only, which may offer therapeutic benefits to counteract cancer cell evasion of the immune system.
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Anticuerpos , Antígeno B7-1 , Antígeno B7-H1 , Receptor de Muerte Celular Programada 1 , Humanos , Antígeno B7-1/metabolismo , Antígeno B7-H1/genética , Antígeno B7-H1/metabolismo , Neoplasias/terapia , Receptor de Muerte Celular Programada 1/metabolismo , Unión Proteica , Sitios de Unión , Cristalografía , Anticuerpos/química , Anticuerpos/metabolismoRESUMEN
Libraries composed of licensed drugs represent a vast repertoire of molecules modulating physiological processes in humans, providing unique opportunities for the discovery of host-targeting antivirals. We screened the Repurposing, Focused Rescue, and Accelerated Medchem (ReFRAME) repurposing library with approximately 12,000 molecules for broad-spectrum coronavirus antivirals and discovered 134 compounds inhibiting an alphacoronavirus and mapping to 58 molecular target categories. Dominant targets included the 5-hydroxytryptamine receptor, the dopamine receptor, and cyclin-dependent kinases. Gene knock-out of the drugs' host targets including cathepsin B and L (CTSB/L; VBY-825), the aryl hydrocarbon receptor (AHR; Phortress), the farnesyl-diphosphate farnesyltransferase 1 (FDFT1; P-3622), and the kelch-like ECH-associated protein 1 (KEAP1; Omaveloxolone), significantly modulated HCoV-229E infection, providing evidence that these compounds inhibited the virus through acting on their respective host targets. Counter-screening of all 134 primary compound candidates with SARS-CoV-2 and validation in primary cells identified Phortress, an AHR activating ligand, P-3622-targeting FDFT1, and Omaveloxolone, which activates the NFE2-like bZIP transcription factor 2 (NFE2L2) by liberating it from its endogenous inhibitor KEAP1, as antiviral candidates for both an Alpha- and a Betacoronavirus. This study provides an overview of HCoV-229E repurposing candidates and reveals novel potentially druggable viral host dependency factors hijacked by diverse coronaviruses.
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Coronavirus Humano 229E , Infecciones por Coronavirus , Tiazoles , Triterpenos , Humanos , Proteína 1 Asociada A ECH Tipo Kelch/metabolismo , Reposicionamiento de Medicamentos , Factor 2 Relacionado con NF-E2/metabolismo , Coronavirus Humano 229E/metabolismo , Antivirales/farmacología , Antivirales/uso terapéuticoRESUMEN
Retinitis pigmentosa (RP) is an inherited retinal disorder characterized by the degeneration of photoreceptors. RhoP23H/+ mice, which carry a Pro23His mutation in the RHODOPSIN (Rho) gene, are one of the most studied animal models for RP. However, except for the photoreceptors, other retinal neural cells have not been fully investigated in this model. Here, we record the temporal changes of the retina by optical coherence tomography (OCT) imaging of the RhoP23H/+ mice, from early to mid-phase of retinal degeneration. Based on thickness analysis, we identified a natural retinal thickness adaption in wild-type mice during early adulthood and observed morphological compensation of the inner retina layer to photoreceptor degeneration in the RhoP23H/+ mice, primarily on the inner nuclear layer (INL). RhoP23H/+ mice findings were further validated via: histology showing the negative correlation of INL and ONL thicknesses; as well as electroretinogram (ERG) showing an increased b-wave to a-wave ratio. These results unravel the sequential morphologic events in this model and suggest a better understanding of retinal degeneration of RP for future studies.
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Degeneración Retiniana , Retinitis Pigmentosa , Ratones , Animales , Degeneración Retiniana/diagnóstico , Degeneración Retiniana/genética , Degeneración Retiniana/patología , Rodopsina/genética , Retina/patología , Retinitis Pigmentosa/genética , Retinitis Pigmentosa/patología , Electrorretinografía , Modelos Animales de EnfermedadRESUMEN
BACKGROUND: The Uncontrollable Mortality Risk Hypothesis (UMRH) states that those who are more likely to die due to factors beyond their control should be less motivated to invest in preventative health behaviors. Greater levels of perceived uncontrollable mortality risk (PUMR) have been associated with lower health effort in previous research, but the topic remains understudied. PURPOSE: To examine the evidence for the UMRH by replicating a previous study investigating the effects of PUMR on social gradients in health effort, and conducting a mini meta-analysis of the overall relationship between PUMR and health effort. METHODS: We replicated Pepper and Nettle (2014), who reported a negative relationship between PUMR and health effort, and that the positive effect of subjective socioeconomic position on health effort was explained away by PUMR. We also compared the predictive effect of PUMR on health effort with that of dimensions from the Multidimensional Health Locus of Control scale-a well-used measure of a similar construct, which is frequently found to be associated with health behavior. Finally, we conducted a mini meta-analysis of the relationship between PUMR and health effort from the available research. RESULTS: PUMR was negatively associated with health effort, and mediated 24% of the total effect of subjective socioeconomic position on health effort, though this mediation effect was weaker than in Pepper and Nettle (2014). PUMR was shown to be a substantially stronger predictor of health effort than the relevant dimensions of the MHLC scale. Finally, our mini meta-analysis indicated a medium-sized negative relationship between PUMR and health effort. CONCLUSIONS: Our findings offer support for the role of PUMR in mediating the relationship between subjective socioeconomic position and health effort. The results highlight the importance of measuring and understanding PUMR in studying socioeconomic inequalities in health behaviors. We discuss potential areas for future research, including determining the accuracy of PUMR, investigating influential cues, examining the role of media in shaping risk perceptions, and understanding individuals' awareness of their own perceptions of mortality risk.
Previous research suggests that people who are more likely to die due to uncontrollable factors are less motivated to look after their health. This is because they are less likely to live to see the long-term benefits of a healthy lifestyle. The purpose of this study is to examine and expand upon previous research investigating the relationship between perceptions of uncontrollable mortality risk and the amount of effort people devote to their health. Our findings support past research and show that the more people feel their risk of dying is out of their control, the less effort they put into looking after their health. Our analysis suggests there is a medium-strength relationship between perceived uncontrollable mortality risk and health effort, which we argue warrants further empirical investigation. The strength of this relationship emphasizes the importance of improving the safety of people's living environments and highlights the positive impact that this can have on health behaviors.
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Conductas Relacionadas con la Salud , HumanosRESUMEN
BACKGROUND: Attention deficit hyperactivity disorder (ADHD) is one of the more common neuropsychiatric disorders in women of reproductive age. Our objective was to compare perinatal outcomes between women with an ADHD diagnosis and those without. METHODS: A retrospective population-based cohort study utilizing the Healthcare Cost and Utilization Project, Nationwide Inpatient Sample (HCUP-NIS) United States database. The study included all women who either delivered or experienced maternal death from 2004 to 2014. Perinatal outcomes were compared between women with an ICD-9 diagnosis of ADHD and those without. RESULTS: Overall, 9,096,788 women met the inclusion criteria. Amongst them, 10,031 women had a diagnosis of ADHD. Women with ADHD, compared to those without, were more likely to be younger than 25 years of age; white; to smoke tobacco during pregnancy; to use illicit drugs; and to suffer from chronic hypertension, thyroid disorders, and obesity (p < 0.001 for all). Women in the ADHD group, compared to those without, had a higher rate of hypertensive disorders of pregnancy (HDP) (aOR 1.36, 95% CI 1.28-1.45, p < 0.001), cesarean delivery (aOR 1.19, 95% CI 1.13-1.25, p < 0.001), chorioamnionitis (aOR 1.34, 95% CI 1.17-1.52, p < 0.001), and maternal infection (aOR 1.33, 95% CI 1.19-1.5, p < 0.001). Regarding neonatal outcomes, patients with ADHD, compared to those without, had a higher rate of small-for-gestational-age neonate (SGA) (aOR 1.3, 95% CI 1.17-1.43, p < 0.001), and congenital anomalies (aOR 2.77, 95% CI 2.36-3.26, p < 0.001). CONCLUSION: Women with a diagnosis of ADHD had a higher incidence of a myriad of maternal and neonatal complications, including cesarean delivery, HDP, and SGA neonates.
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Trastorno por Déficit de Atención con Hiperactividad , Bases de Datos Factuales , Complicaciones del Embarazo , Resultado del Embarazo , Humanos , Femenino , Trastorno por Déficit de Atención con Hiperactividad/epidemiología , Embarazo , Adulto , Estudios Retrospectivos , Complicaciones del Embarazo/epidemiología , Recién Nacido , Resultado del Embarazo/epidemiología , Estados Unidos/epidemiología , Adulto Joven , Cesárea/estadística & datos numéricos , Parto Obstétrico/estadística & datos numéricos , Hipertensión Inducida en el Embarazo/epidemiologíaRESUMEN
OBJECTIVES: Gastrointestinal system (GIS) cancer in pregnancy is a rare disease. Our aim was to evaluate the association between this type of cancer and pregnancy, delivery and neonatal outcomes. METHODS: We conducted a retrospective population-based cohort study using the Healthcare Cost and Utilization Project, Nation-wide Inpatient Sample (HCUP-NIS). We included all women who delivered or had a maternal death in the US between 2004 and 2014. We compared women with an ICD-9 diagnosis of GIS cancer to those without. Pregnancy, delivery, and neonatal outcomes were compared between the two groups. RESULTS: A total of 9,096,788 women met inclusion criteria. Amongst them, 194 women (2/100,000) had a diagnosis of GIS cancer during pregnancy. Women with GIS cancer, compared to those without, were more likely to be Caucasian, older than 35 years of age, and to suffer from obesity, chronic hypertension, pregestational diabetes and thyroid disease. The cancer group had a lower rate of spontaneous vaginal delivery (aOR 0.2, 95â¯% CI 0.13-0.27, p<0.001), and a higher rate of preterm delivery (aOR 1.85, 95â¯% CI 1.21-2.82, p=0.04), and of maternal complications such as blood transfusion (aOR 24.7, 95â¯% CI 17.11-35.66, p<0.001), disseminated intravascular coagulation (aOR 14.56, 95â¯% CI 3.56-59.55, p<0.001), venous thromboembolism (aOR 9.4, 95â¯% CI 2.3-38.42, p=0.002) and maternal death (aOR 8.02, 95â¯% CI 2.55-25.34, p<0.001). Neonatal outcomes were comparable between the two groups. CONCLUSIONS: Women with a diagnosis of GIS cancer in pregnancy have a higher incidence of maternal complications including maternal death, without any differences in neonatal outcomes.
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Muerte Materna , Neoplasias , Embarazo , Recién Nacido , Femenino , Humanos , Resultado del Embarazo/epidemiología , Estudios Retrospectivos , Cesárea , Estudios de CohortesRESUMEN
PURPOSE: Cerebrovascular accidents (CVAs) and transient ischemic attacks (TIAs) are uncommon neurologic events in women of childbearing age. We aimed to compare pregnancy, delivery, and neonatal outcomes between women who suffered from a CVA and those who experienced a TIA. METHODS: A retrospective population-based cohort study was performed using the Healthcare Cost and Utilization Project, Nationwide Inpatient Sample. Included were all pregnant women who delivered or had a maternal death in the US between 2004 and 2014. We compared women with an ICD-9 diagnosis of a CVA before or during pregnancy to those diagnosed with a TIA before, during the pregnancy, or during the delivery admission. Pregnancy and perinatal outcomes were compared between the two groups, using multivariate logistic regression to control for confounders. RESULTS: Among 9,096,788 women in the database, 898 met the inclusion criteria. Of them, 706 women (7.7/100,000) had a CVA diagnosis, and 192 (2.1/100,000) had a TIA diagnosis. Women with a CVA, compared to those with a TIA, had a higher rate of pregnancy-induced hypertension (aOR 3.82,95%CI 2.14-6.81, p < 0.001); preeclampsia (aOR 2.6,95%CI 1.3-5.2, p = 0.007), eclampsia (aOR 13.78,95% CI 1.84-103.41, p < 0.001); postpartum hemorrhage (aOR 4.52,95%CI 1.31-15.56, p = 0.017), blood transfusion (aOR 5.57,95%CI 1.65-18.72, p = 0.006), and maternal death (54 vs. 0 cases, 7.6% vs. 0%), with comparable neonatal outcomes. CONCLUSION: Women diagnosed with a CVA before or during pregnancy had a higher incidence of myriad maternal complications, including hypertensive disorders of pregnancy, postpartum hemorrhage, and death, compared to women with a TIA diagnosis, with comparable neonatal outcomes, stressing the different prognoses of these two conditions, and the importance of these patients' diligent follow-up and care.
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Male and female 3xTg-AD mice between 5 and 24 mo of age and their B6129F2/J wild-type controls were tested on a series of 18 olfactory discrimination and reversal tasks in an operant olfactometer. All mice learned the odor discriminations and reversals to a criterion of 85% correct, but the 3xTg-AD mice made fewer errors than the B6129F2/J mice in the odor discriminations and in the first six reversal learning tasks. Many mice showed evidence of near errorless learning, and on the reversal tasks the 3xTg-AD mice showed more instances of near errorless learning than the B6129F2/J mice. There was no evidence of an age effect on odor discrimination, but there was a decrease in errorless reversal learning in aged B6129F2/J mice. In long-term memory tests, there was an increase in the number of errors made but no genotype difference. The high level of performance indicates that the mice were able to develop a "learning to learn" strategy. The finding that the 3xTg-AD mice outperformed their littermate controls provides an example of paradoxical functional facilitation in these mice.
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Aprendizaje Inverso , Olfato , Ratones , Masculino , Femenino , Animales , Aprendizaje SeriadoRESUMEN
ABSTRACT: Interprofessional collaboration is an essential competency for nurses in today's complex healthcare environment. The Interprofessional Education Collaborative (IPEC) four competencies of values, teamwork, roles, and communication provide the organizing framework for effective interprofessional collaboration. In this article, the four competencies are used to explore biblical underpinnings and principles of collaboration for Christian nurses, showing how interprofessional collaboration helps achieve one's faith-based and professional commitments.
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Osteoporosis and multiple sclerosis are highly prevalent diseases with limited treatment options. In light of these unmet medical needs, novel therapeutic approaches are urgently sought. Previously, the activation of the transmembrane receptor Plexin-B1 by its ligand semaphorin 4D (Sema4D) has been shown to suppress bone formation and promote neuroinflammation in mice. However, it is unclear whether inhibition of this receptor-ligand interaction by an anti-Plexin-B1 antibody could represent a viable strategy against diseases related to these processes. Here, we raised and systematically characterized a monoclonal antibody directed against the extracellular domain of human Plexin-B1, which specifically blocks the binding of Sema4D to Plexin-B1. In vitro, we show that this antibody inhibits the suppressive effects of Sema4D on human osteoblast differentiation and mineralization. To test the therapeutic potential of the antibody in vivo, we generated a humanized mouse line, which expresses transgenic human Plexin-B1 instead of endogenous murine Plexin-B1. Employing these mice, we demonstrate that the anti-Plexin-B1 antibody exhibits beneficial effects in mouse models of postmenopausal osteoporosis and multiple sclerosis in vivo. In summary, our data identify an anti-Plexin-B1 antibody as a potential therapeutic agent for the treatment of osteoporosis and multiple sclerosis.
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Anticuerpos Monoclonales , Antígenos CD , Esclerosis Múltiple , Proteínas del Tejido Nervioso , Osteoporosis Posmenopáusica , Receptores de Superficie Celular , Semaforinas , Animales , Anticuerpos Monoclonales/uso terapéutico , Antígenos CD/metabolismo , Modelos Animales de Enfermedad , Femenino , Humanos , Ligandos , Ratones , Esclerosis Múltiple/terapia , Proteínas del Tejido Nervioso/antagonistas & inhibidores , Proteínas del Tejido Nervioso/metabolismo , Osteoporosis Posmenopáusica/terapia , Receptores de Superficie Celular/antagonistas & inhibidores , Receptores de Superficie Celular/metabolismo , Semaforinas/antagonistas & inhibidores , Semaforinas/metabolismoRESUMEN
Predicting the impact of noncoding genetic variation requires interpreting it in the context of three-dimensional genome architecture. We have developed deepC, a transfer-learning-based deep neural network that accurately predicts genome folding from megabase-scale DNA sequence. DeepC predicts domain boundaries at high resolution, learns the sequence determinants of genome folding and predicts the impact of both large-scale structural and single base-pair variations.
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Genoma Humano/genética , Genómica/métodos , Modelos Genéticos , Redes Neurales de la Computación , Secuencia de Bases , Factor de Unión a CCCTC/genética , Cromatina/genética , Simulación por Computador , Variación Estructural del Genoma , HumanosRESUMEN
C-type lectin domain-containing proteins (CTLDcps) shape host responses to pathogens and infectious disease outcomes. Previously, we identified the murine CTLDcp Cd302 as restriction factor, limiting hepatitis C virus (HCV) infection of murine hepatocytes. In this study, we investigated in detail the human orthologue's ability to restrict HCV infection in human liver cells. CD302 overexpression in Huh-7.5 cells potently inhibited infection of diverse HCV chimeras representing seven genotypes. Transcriptional profiling revealed abundant CD302 mRNA expression in human hepatocytes, the natural cellular target of HCV. Knockdown of endogenously expressed CD302 modestly enhanced HCV infection of Huh-7.5 cells and primary human hepatocytes. Functional analysis of naturally occurring CD302 transcript variants and engineered CD302 mutants showed that the C-type lectin-like domain (CTLD) is essential for HCV restriction, whereas the cytoplasmic domain (CPD) is dispensable. Coding single nucleotide polymorphisms occurring in human populations and mapping to different domains of CD302 did not influence the capacity of CD302 to restrict HCV. Assessment of the anti-HCV phenotype at different life cycle stages indicated that CD302 preferentially targets the viral entry step. In contrast to the murine orthologue, overexpression of human CD302 did not modulate downstream expression of nuclear receptor-controlled genes. Ectopic CD302 expression restricted infection of liver tropic hepatitis E virus (HEV), while it did not affect infection rates of two respiratory viruses, including respiratory syncytial virus (RSV) and the alpha coronavirus HVCoV-229E. Together, these findings suggest that CD302 contributes to liver cell-intrinsic defense against HCV and might mediate broader antiviral defenses against additional hepatotropic viruses. IMPORTANCE The liver represents an immunoprivileged organ characterized by enhanced resistance to immune responses. However, the importance of liver cell-endogenous, noncytolytic innate immune responses in pathogen control is not well defined. Although the role of myeloid cell-expressed CTLDcps in host responses to viruses has been characterized in detail, we have little information about their potential functions in the liver and their relevance for immune responses in this organ. Human hepatocytes endogenously express the CTLDcp CD302. Here, we provide evidence that CD302 limits HCV infection of human liver cells, likely by inhibiting a viral cell entry step. We confirm that the dominant liver-expressed transcript variant, as well as naturally occurring coding variants of CD302, maintain the capacity to restrict HCV. We further show that the CTLD of the protein is critical for the anti-HCV activity and that overexpressed CD302 limits HEV infection. Thus, CD302 likely contributes to human liver-intrinsic antiviral defenses.
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Hepacivirus , Hepatitis C , Lectinas Tipo C , Receptores de Superficie Celular , Antivirales/metabolismo , Hepacivirus/fisiología , Hepatitis C/inmunología , Hepatocitos/inmunología , Hepatocitos/virología , Humanos , Lectinas Tipo C/genética , Lectinas Tipo C/metabolismo , Receptores de Superficie Celular/genética , Receptores de Superficie Celular/metabolismo , Replicación ViralRESUMEN
Populations on the edge of a species' distribution may represent an important source of adaptive diversity, yet these populations tend to be more fragmented and are more likely to be geographically isolated. Lack of genetic exchanges between such populations, due to barriers to animal movement, can not only compromise adaptive potential but also lead to the fixation of deleterious alleles. The south-eastern edge of chimpanzee distribution is particularly fragmented, and conflicting hypotheses have been proposed about population connectivity and viability. To address this uncertainty, we generated both mitochondrial and MiSeq-based microsatellite genotypes for 290 individuals ranging across western Tanzania. While shared mitochondrial haplotypes confirmed historical gene flow, our microsatellite analyses revealed two distinct clusters, suggesting two populations currently isolated from one another. However, we found evidence of high levels of gene flow maintained within each of these clusters, one of which covers an 18,000 km2 ecosystem. Landscape genetic analyses confirmed the presence of barriers to gene flow with rivers and bare habitats highly restricting chimpanzee movement. Our study demonstrates how advances in sequencing technologies, combined with the development of landscape genetics approaches, can resolve ambiguities in the genetic history of critical populations and better inform conservation efforts of endangered species.
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Variación Genética , Genética de Población , Animales , Variación Genética/genética , Ecosistema , Pan troglodytes/genética , Flujo Génico , Repeticiones de Microsatélite/genética , Haplotipos/genéticaRESUMEN
In electrosynthesis, electron transfer (ET) mediators are normally chosen such that they are more easily reduced (or oxidised) than the substrate for cathodic (or anodic) processes; setting the electrode potential to the mediator therefore ensures selective heterogeneous ET with the mediator at the electrode, rather than the substrate. The current work investigates the opposite, and counter intuitive, situation for a successful mediated electroreductive process where the mediator (phenanthrene) has a reduction potential that is negative to that of the substrate, and the cathode potential is set negative to both (Eele < EM < Es). Simulations reveal a complex interplay between mass transport, the relative concentrations of the mediator and substrate as well as the heterogeneous and homogeneous rate constants for multiple steps, which under suitable conditions, leads to separation of the homogeneous chemistry in a reaction layer detached from the electrode. Reaction layer detachment is a spatio-temporal effect arising due to opposing fluxes of the mediator radical anion MË- and the substrate 1, which ultimately prevents 1 from reaching the electrode, thereby affording a different reaction pathway. Simulations representative of unstirred batch (1D) and flow (2D) electrolysis are presented, which qualitatively reproduce the experimental selectivity outcomes for mediated and unmediated electroreductive cyclisation of aryl iodide 1. The potential to use highly reducing homogeneous ET agents, possessing reduction potentials beyond those of the substrates, offers exciting opportunities in mediated electrosynthesis.
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INTRODUCTION: Adults with depression have higher rates of cigarette smoking and are more likely to relapse than those without depression. Pharmacological, psychological, and combined interventions have largely yielded small improvements in smoking outcomes for adults with depression. Aerobic exercise (AE) may facilitate smoking cessation in this subpopulation. METHODS: This study was a 12-week two-arm randomized controlled trial that evaluated the effect of a moderate-intensity AE program compared to a health education contact (HEC) control on smoking cessation in adults with elevated depressive symptoms (mild to severe). Participants (n=231) were randomized to AE or HEC and received smoking cessation treatment (telephone counseling and nicotine replacement therapy). Primary (biologically confirmed 7-day point prevalence abstinence) and secondary (depressive symptoms, objective and self-reported physical activity, and cardiorespiratory fitness) outcomes were assessed at baseline, 3-, 6-, and 12-months. Data were analyzed with mixed-effects generalized linear models controlling for age, gender, nicotine dependence, history of major depression disorder, and month of follow-up assessment. RESULTS: There were no significant differences in primary or secondary outcomes between the AE and HEC groups. CONCLUSIONS: The AE program was not superior to HEC in facilitating smoking cessation, increases in physical activity, or improved depressive symptoms. Given evidence for the positive acute effects of exercise on mood and smoking urges, future research should consider testing alternative exercise approaches for aiding smoking cessation beyond structured, aerobic exercise programs. IMPLICATIONS: This study found that an adjunctive aerobic exercise (AE) program was not superior to a health education contact control for adults with elevated depressive symptoms, all of whom also received standard smoking cessation treatment. This finding adds to the growing body of literature that structured aerobic exercise programs for smoking cessation may have limited efficacy for cessation outcomes. Future research is needed to test alternative methods of integrating AE into smoking cessation treatment, such as strategically using exercise to manage cravings and low mood in the moment.
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BACKGROUND: Individuals with hypertensive disorders of pregnancy (HDP) have an elevated lifetime risk of chronic hypertension, metabolic syndrome, and premature cardiovascular disease. Because breastfeeding duration and exclusivity have been associated in observational studies with improved cardiovascular health, optimizing breastfeeding in those with HDP might be an unrealized cardio-prevention approach, in particular because individuals with HDP have more breastfeeding challenges. Breastfeeding supportive interventions targeting one's breastfeeding self-efficacy have been shown to improve breastfeeding rates. METHODS: We designed an open-label, multi-center 1:1 randomized behavioral trial to test whether a previously validated self-efficacy enhancing breastfeeding intervention can improve breastfeeding duration and/or exclusivity, and lower postpartum blood pressure at 12 months. Randomization is computer-generated and stratified by site (four hospitals in Montreal, Quebec and one hospital in Kingston, Ontario; all in Canada). Included are breastfeeding participants with HDP (chronic/gestational hypertension or preeclampsia) who delivered a live singleton infant at > 34 weeks, speak English or French, and have no contraindications to breastfeeding. Informed and written consent is obtained at hospitalization for delivery or a re-admission with hypertension within 1 week of discharge. Participants assigned to the intervention group receive a breastfeeding self-efficacy-based intervention delivered by a trained lactation consultant in hospital, with continued reactive/proactive support by phone or text message for up to 6 months postpartum. Regardless of group assignment, participants are followed for self-reported outcomes, automated office blood pressure, and home blood pressure at several time points with end of follow-up at 12 months. DISCUSSION: This study will assess whether an intensive nurse-led behavioral intervention can improve breastfeeding rates and, in turn, postpartum blood pressure - an early marker for atherosclerotic cardiovascular disease. If effective, this form of enhanced breastfeeding support, along with closer BP and metabolic surveillance, can be implemented broadly in individuals lactating after HDP. TRIAL REGISTRATION: ClinicalTrials.gov, # NCT04580927 , registered on Oct 9, 2020.