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Chimeric antigen receptor (CAR) T-cell therapies have demonstrated transformative efficacy in treating B-cell malignancies. However, high cost and manufacturing complexities hinder their widespread use. To overcome these hurdles, we have developed the VivoVecTM platform, a lentiviral vector capable of generating CAR T-cells in vivo. Here we describe the incorporation of T cell activation and costimulatory signals onto the surface of VivoVecTM particles (VVPs) in the form of a multi-domain fusion protein and show enhanced in vivo transduction and improved CAR-T cell antitumor functionality. Furthermore, in the absence of lymphodepleting chemotherapy, administration of VVPs into non-human primates resulted in the robust generation of anti-CD20 CAR T-cells and the complete depletion of B cells for more than 10 weeks. These data validate the VivoVecTM platform in a translationally relevant model and support its transition into human clinical testing, offering a paradigm shift in the field of CAR T-cell therapies.
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Rotavirus infection is a leading cause of gastroenteritis in children worldwide; the genome of this virus is composed of 11 segments of dsRNA packed in a triple-layered protein capsid. Here, we investigated the role of nucleolin, a protein with diverse RNA-binding domains, in rotavirus infection. Knocking down the expression of nucleolin in MA104 cells by RNA interference resulted in a remarkable 6.3-fold increase in the production of infectious rhesus rotavirus (RRV) progeny, accompanied by an elevated synthesis of viral mRNA and genome copies. Further analysis unveiled an interaction between rotavirus segment 10 (S10) and nucleolin, potentially mediated by G-quadruplex domains on the viral genome. To determine whether the nucleolin-RNA interaction regulates RRV replication, MA104 cells were transfected with AGRO100, a compound that forms G4 structures and selectively inhibits nucleolin-RNA interactions by blocking the RNA-binding domains. Under these conditions, viral production increased by 1.5-fold, indicating the inhibitory role of nucleolin on the yield of infectious viral particles. Furthermore, G4 sequences were identified in all 11 RRV dsRNA segments, and transfection of oligonucleotides representing G4 sequences in RRV S10 induced a significant increase in viral production. These findings show that rotavirus replication is negatively regulated by nucleolin through the direct interaction with the viral RNAs by sequences forming G4 structures.IMPORTANCEViruses rely on cellular proteins to carry out their replicative cycle. In the case of rotavirus, the involvement of cellular RNA-binding proteins during the replicative cycle is a poorly studied field. In this work, we demonstrate for the first time the interaction between nucleolin and viral RNA of rotavirus RRV. Nucleolin is a cellular protein that has a role in the metabolism of ribosomal rRNA and ribosome biogenesis, which seems to have regulatory effects on the quantity of viral particles and viral RNA copies of rotavirus RRV. Our study adds a new component to the current model of rotavirus replication, where cellular proteins can have a negative regulation on rotavirus replication.
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Nucleolina , RNA Viral , Infecções por Rotavirus , Rotavirus , Humanos , Nucleolina/metabolismo , RNA Viral/genética , Rotavirus/fisiologia , Infecções por Rotavirus/virologia , Replicação ViralRESUMO
Astroviruses are highly divergent and infect a wide variety of animal hosts. In 2009, a genetically divergent human astrovirus (HAstV) strain VA1 was first identified in an outbreak of acute gastroenteritis. This strain has also been associated with fatal central nervous system disease. In this work, we report the isolation of three high-affinity neutralizing monoclonal antibodies (Nt-MAbs) targeting the capsid spike domain of HAstV-VA1. These antibodies (7C8, 2A2, 3D8) were used to select individual HAstV-VA1 mutants resistant to their neutralizing activity and a HAstV-VA1 triple mutant that escapes neutralization from all three Nt-MAbs. Sequencing of the virus genome capsid region revealed escape mutations that map to the surface of the capsid spike domain, define three potentially independent neutralization epitopes, and help delineate four antigenic sites in human astroviruses. Notably, two of the escape mutations were found to be present in the spike sequence of the HAstV-VA1-PS strain isolated from an immunodeficient patient with encephalitis, suggesting that those mutations arose as a result of the immune pressure generated by the patient's immunotherapy. In agreement with this observation, human serum samples exhibiting strong neutralization activity against wild-type HAstV-VA1 had a 2.6-fold reduction in neutralization titer when evaluated against the triple-escape HAstV-VA1 mutant, suggesting that both mouse and human antibody responses target shared neutralization epitopes. The isolated Nt-MAbs reported in this work will help to characterize the functional domains of the virus during cell entry and have the potential for developing a specific antibody therapy for the neurological disease associated with HAstV-VA1. IMPORTANCE: Human astroviruses (HAstVs) have been historically associated with acute gastroenteritis. However, the genetically divergent HAstV-VA1 strain has been associated with central nervous system disease. In this work high-affinity neutralizing monoclonal antibodies directed to HAstV-VA1 were isolated and characterized. The proposed binding sites for these antibodies and for neutralizing antibodies against classical HAstVs suggest that there are at least four neutralization sites on the capsid spike of astroviruses. Our data show that natural infection with human astrovirus VA1 elicits a robust humoral immune response that targets the same antigenic sites recognized by the mouse monoclonal antibodies and strongly suggests the emergence of a variant HAstV-VA1 virus in an immunodeficient patient with prolonged astrovirus infection. The isolated Nt-MAb reported in this work will help to define the functional sites of the virus involved in cell entry and hold promise for developing a specific antibody therapy for the neurological disease associated with HAstV-VA1.
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Anticorpos Monoclonais , Anticorpos Neutralizantes , Anticorpos Antivirais , Epitopos , Humanos , Animais , Anticorpos Neutralizantes/imunologia , Camundongos , Epitopos/imunologia , Anticorpos Antivirais/imunologia , Anticorpos Monoclonais/imunologia , Proteínas do Capsídeo/imunologia , Proteínas do Capsídeo/genética , Mamastrovirus/imunologia , Mamastrovirus/genética , Mutação , Infecções por Astroviridae/imunologia , Infecções por Astroviridae/virologia , Testes de NeutralizaçãoRESUMO
Between 2.5 and 28% of people infected with SARS-CoV-2 suffer Long COVID or persistence of symptoms for months after acute illness. Many symptoms are neurological, but the brain changes underlying the neuropsychological impairments remain unclear. This study aimed to provide a detailed description of the cognitive profile, the pattern of brain alterations in Long COVID and the potential association between them. To address these objectives, 83 patients with persistent neurological symptoms after COVID-19 were recruited, and 22 now healthy controls chosen because they had suffered COVID-19 but did not experience persistent neurological symptoms. Patients and controls were matched for age, sex and educational level. All participants were assessed by clinical interview, comprehensive standardized neuropsychological tests and structural MRI. The mean global cognitive function of patients with Long COVID assessed by ACE III screening test (Overall Cognitive level - OCLz= -0.39± 0.12) was significantly below the infection recovered-controls (OCLz= +0.32± 0.16, p< 0.01). We observed that 48% of patients with Long COVID had episodic memory deficit, with 27% also impaired overall cognitive function, especially attention, working memory, processing speed and verbal fluency. The MRI examination included grey matter morphometry and whole brain structural connectivity analysis. Compared to infection recovered controls, patients had thinner cortex in a specific cluster centred on the left posterior superior temporal gyrus. In addition, lower fractional anisotropy (FA) and higher radial diffusivity (RD) were observed in widespread areas of the patients' cerebral white matter relative to these controls. Correlations between cognitive status and brain abnormalities revealed a relationship between altered connectivity of white matter regions and impairments of episodic memory, overall cognitive function, attention and verbal fluency. This study shows that patients with neurological Long COVID suffer brain changes, especially in several white matter areas, and these are associated with impairments of specific cognitive functions.
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IL-13 signaling polarizes macrophages to an M2 alternatively activated phenotype, which regulates tissue repair and anti-inflammatory responses. However, an excessive activation of this pathway leads to severe pathologies, such as allergic airway inflammation and asthma. In this work, we identified NOTCH4 receptor as an important modulator of M2 macrophage activation. We show that the expression of NOTCH4 is induced by IL-13, mediated by Janus kinases and AP1 activity, probably mediated by the IL-13Rα1 and IL-13Rα2 signaling pathway. Furthermore, we demonstrate an important role for NOTCH4 signaling in the IL-13 induced gene expression program in macrophages, including various genes that contribute to pathogenesis of the airways in asthma, such as ARG1, YM1, CCL24, IL-10, or CD-163. We also demonstrate that NOTCH4 signaling modulates IL-13-induced gene expression by increasing IRF4 activity, mediated, at least in part, by the expression of the histone H3K27me3 demethylase JMJD3, and by increasing AP1-dependent transcription. In summary, our results provide evidence for an important role of NOTCH4 signaling in alternative activation of macrophages by IL-13 and suggest that NOTCH4 may contribute to the increased severity of lesions in M2 inflammatory responses, such as allergic asthma, which points to NOTCH4 as a potential new target for the treatment of these pathologies.
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Asma , Interleucina-13 , Humanos , Macrófagos/metabolismo , Inflamação/metabolismo , Transdução de Sinais/genética , Receptor Notch4/metabolismoRESUMO
BACKGROUND: Postoperative pancreatic fistula (POPF) is one of the most feared and common complications following pancreatoduodenectomies. This study aims to evaluate the performance of different scales in predicting POPF using magnetic resonance imaging (MRI), including estimation of the pancreatic duct diameter, pancreatic texture, main duct index, relation to the portal vein, and intra-abdominal fat thickness. MATERIALS AND METHODS: A retrospective diagnostic test study was designed. Between January 2017 and December 2021, 133 pancreatoduodenectomies were performed at our institution. The performance for predicting overall POPF and clinically relevant POPF (CR-POPF) was evaluated using a receiver operating characteristic (ROC) curve. RESULTS: A total of 96 patients were included in the study, of whom 26 patients experienced overall POPF, and 8 patients had CR-POPF. When analyzing the predictive value of each of the different scores applied, the Birmingham score showed the highest performance for predicting overall POPF and CR-POPF with an AUC (area under the curve) of 0.815 (95 % CI 0.725-0.906) and 0.813 (0.679-0.947), respectively. CONCLUSION: The Birmingham scale demonstrated the highest predictive performance for POPF. It is a simple scale with only two variables that can be obtained preoperatively using MRI. Based on these results, we recommend its use in patients undergoing pancreatoduodenectomy.
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Imageamento por Ressonância Magnética , Fístula Pancreática , Pancreaticoduodenectomia , Complicações Pós-Operatórias , Humanos , Pancreaticoduodenectomia/efeitos adversos , Fístula Pancreática/etiologia , Fístula Pancreática/diagnóstico por imagem , Feminino , Masculino , Pessoa de Meia-Idade , Idoso , Estudos Retrospectivos , Complicações Pós-Operatórias/diagnóstico por imagem , Complicações Pós-Operatórias/etiologia , Adulto , Valor Preditivo dos Testes , Pâncreas/diagnóstico por imagem , Pâncreas/cirurgia , Pâncreas/patologia , Idoso de 80 Anos ou mais , Curva ROCRESUMO
There is limited information on the antibody responses against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in subjects from developing countries with populations having a high incidence of co-morbidities. Here, we analysed the immunogenicity of homologous schemes using the ChAdOx1-S, Sputnik V, or BNT162b2 vaccines and the effect of a booster dose with ChAdOx1-S in middle-aged adults who were seropositive or seronegative to the SARS-CoV-2 spike protein before vaccination. The study was conducted post-vaccination with a follow-up of 4 months for antibody titre using enzyme-linked immunosorbent assay (ELISA) and pseudovirus (PV) neutralization assays (PNAs). All three vaccines elicited a superior IgG anti-receptor-binding domain (RBD) and neutralization response against the Alpha and Delta variants when administered to individuals with a previous infection by SARS-CoV-2. The booster dose spiked the neutralization activity among individuals with and without a prior SARS-CoV-2 infection. The ChAdOx1-S vaccine induced weaker antibody responses in infection-naive subjects. A follow-up of 4 months post-vaccination showed a drop in antibody titre, with about 20% of the infection-naive and 100% of SARS-CoV-2 pre-exposed participants with detectable neutralization capacity against Alpha pseudovirus (Alpha-PV) and Delta PV (Delta-PV). Our observations support the use of different vaccines in a country with high seroprevalence at the vaccination time.
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COVID-19 , Glicoproteína da Espícula de Coronavírus , Vacinas , Adulto , Pessoa de Meia-Idade , Humanos , SARS-CoV-2 , México/epidemiologia , Vacina BNT162 , Estudos Soroepidemiológicos , COVID-19/epidemiologia , COVID-19/prevenção & controle , Imunização , Vacinação , Imunidade , Anticorpos Antivirais , Anticorpos NeutralizantesRESUMO
BACKGROUND: The aim of this study is to evaluate morbidity and mortality in patients taken to conversion to open procedure (CO) and subtotal laparoscopic cholecystectomy (SLC) as bailout procedures when performing difficult laparoscopic cholecystectomy. METHOD: This observational cohort study retrospectively analyzed patients taken to SLC or CO as bailout surgery during difficult laparoscopic cholecystectomy between 2014 and 2022. Univariable and multivariable logistic regression models were used to identify prognostic factors for morbimortality. RESULTS: A total of 675 patients were included. Of the 675 patients (mean [SD] age 63.85 ± 16.00 years; 390 [57.7%] male) included in the analysis, 452 (67%) underwent CO and 223 (33%) underwent SLC. Overall, neither procedure had an increased risk of major complications (89 [19.69%] vs 35 [15.69%] P.207). However, CO had an increased risk of bile duct injury (18 [3.98] vs 1 [0.44] P.009), bleeding (mean [SD] 165.43 ± 368.57 vs 43.25 ± 123.42 P < .001), intestinal injury (20 [4.42%] vs 0 [0.00] P.001), and wound infection (18 [3.98%] vs 2 [0.89%] P.026), while SLC had a higher risk of bile leak (15 [3.31] vs 16 [7.17] P.024). On the multivariable analysis, Charlson comorbidity index (odds ratio [OR], 1.20; CI95%, 1.01-1.42), use of anticoagulant agents (OR, 2.56; CI95%, 1.21-5.44), classification of severity of cholecystitis grade III (OR, 2.96; CI95%, 1.48-5.94), and emergency admission (OR, 6.07; CI95%, 1.33-27.74) were associated with presenting major complications. CONCLUSIONS: SLC was less associated with complications; however, there is scant evidence on its long-term outcomes. Further research is needed on SLC to establish if it is the safest in the long-term as a bailout procedure.
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Allergic contact dermatitis (ACD) is a more frequent pathology in adults than in children, because, in most cases, allergic sensitization requires a prolonged exposure time to the allergen, mostly months or years. In fact, the actual incidence and prevalence of ACD in children and adolescents is unknown. However, there is a hypothesis that ACD is increasing in the pediatric population. Among the allergens involved in ACD, the frequency of paraphenylenediamine (PPDA) is increasing. PPDA is one of the five most common contact allergens in the general population and one of the 10 most common contact allergens in children. The most relevant sources today are henna tattoos and hair dyes. Currently, European Union legislation limits the use of PPDA in hair dyes and prohibits its use in henna tattoos. Despite this legislation, the use of henna tattoos with PPDA is becoming more frequent in younger ages. We report an early presentation of ACD by PPDA, with a permanent hypopigmented skin area as an aftermath, in a 7-year-old male child. We believe that health authorities should advise against making these tattoos in children.
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Dermatite Alérgica de Contato , Tinturas para Cabelo , Criança , Adolescente , Adulto , Masculino , Humanos , Tinturas para Cabelo/efeitos adversos , Dermatite Alérgica de Contato/diagnóstico , Dermatite Alérgica de Contato/epidemiologia , Dermatite Alérgica de Contato/etiologia , União EuropeiaRESUMO
BACKGROUND: The laparoscopic cholecystectomy is the treatment of choice for patients with benign biliary disease. It is necessary to evaluate survival after laparoscopic cholecystectomy in patients over 80 years old to determine whether the long-term mortality rate is higher than the reported recurrence rate. If so, this age group could benefit from a more conservative approach, such as antibiotic treatment or cholecystostomy. Therefore, the aim of this study was to evaluate the factors associated with 2 years survival after laparoscopic cholecystectomy in patients over 80 years old. METHODS: We conducted a retrospective observational cohort study. We included all patients over 80 years old who underwent laparoscopic cholecystectomy. Survival analysis was conducted using the KaplanâMeier method. Cox regression analysis was implemented to determine potential factors associated with mortality at 24 months. RESULTS: A total of 144 patients were included in the study, of whom 37 (25.69%) died at the two-year follow-up. Survival curves were compared for different ASA groups, showing a higher proportion of survivors at two years among patients classified as ASA 1-2 at 87.50% compared to ASA 3-4 at 63.75% (p = 0.001). An ASA score of 3-4 was identified as a statistically significant factor associated with mortality, indicating a higher risk (HR: 2.71, CI95%:1.20-6.14). CONCLUSIONS: ASA 3-4 patients may benefit from conservative management due to their higher risk of mortality at 2 years and a lower probability of disease recurrence.
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Colecistectomia Laparoscópica , Colecistite Aguda , Colecistostomia , Doenças da Vesícula Biliar , Humanos , Idoso de 80 Anos ou mais , Colecistectomia Laparoscópica/métodos , Seguimentos , Estudos Retrospectivos , Colecistostomia/métodos , Doenças da Vesícula Biliar/cirurgia , Colecistite Aguda/cirurgia , Resultado do TratamentoRESUMO
Transient receptor potential canonical (TRPC) channels are calcium channels with diverse expression profiles and physiological implications in the retina. Neurons and glial cells of rat retinas with photoreceptor degeneration caused by retinitis pigmentosa (RP) exhibit basal calcium levels that are above those detected in healthy retinas. Inner retinal cells are the last to degenerate and are responsible for maintaining the activity of the visual cortex, even after complete loss of photoreceptors. We considered the possibility that TRPC1 and TRPC5 channels might be associated with both the high calcium levels and the delay in inner retinal degeneration. TRPC1 is known to mediate protective effects in neurodegenerative processes while TRPC5 promotes cell death. In order to comprehend the implications of these channels in RP, the co-localization and subsequent physical interaction between TRPC1 and TRPC5 in healthy retina (Sprague-Dawley rats) and degenerating (P23H-1, a model of RP) retina were detected by immunofluorescence and proximity ligation assays. There was an overlapping signal in the innermost retina of all animals where TRPC1 and TRPC5 physically interacted. This interaction increased significantly as photoreceptor loss progressed. Both channels function as TRPC1/5 heteromers in the healthy and damaged retina, with a marked function of TRPC1 in response to retinal degenerative mechanisms. Furthermore, our findings support that TRPC5 channels also function in partnership with STIM1 in Müller and retinal ganglion cells. These results suggest that an increase in TRPC1/5 heteromers may contribute to the slowing of the degeneration of the inner retina during the outer retinal degeneration.
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Ratos Sprague-Dawley , Degeneração Retiniana , Canais de Cátion TRPC , Animais , Canais de Cátion TRPC/metabolismo , Ratos , Degeneração Retiniana/metabolismo , Degeneração Retiniana/patologia , Retina/metabolismo , Retina/patologia , Células Fotorreceptoras de Vertebrados/metabolismo , Células Fotorreceptoras de Vertebrados/patologia , Retinose Pigmentar/metabolismo , Retinose Pigmentar/patologia , Retinose Pigmentar/genética , Modelos Animais de DoençasRESUMO
Viruses have evolved different strategies to overcome their recognition by the host innate immune system. The addition of caps at their 5' RNA ends is an efficient mechanism not only to ensure escape from detection by the innate immune system but also to ensure the efficient synthesis of viral proteins. Rotavirus mRNAs contain a type 1 cap structure at their 5' end that is added by the viral capping enzyme VP3, which is a multifunctional protein with all the enzymatic activities necessary to add the cap and also functions as an antagonist of the 2'-5'-oligoadenylate synthetase (OAS)/RNase L pathway. Here, the relative abundances of capped and noncapped viral RNAs during the replication cycle of rotavirus were determined. We found that both classes of rotaviral plus-sense RNAs (+RNAs) were encapsidated and that they were present in a 1:1 ratio in the mature infectious particles. The capping of viral +RNAs was dynamic, since different ratios of capped and noncapped RNAs were detected at different times postinfection. Similarly, when the relative amounts of capped and uncapped viral +RNAs produced in an in vitro transcription system were determined, we found that the proportions were very similar to those in the mature viral particles and in infected cells, suggesting that the capping efficiency of VP3, both in vivo and in vitro, might be close to 50%. Unexpectedly, when the effect of simultaneously knocking down the expression of VP3 and RNase L on the cap status of viral +RNAs was evaluated, we found that, even though at late times postinfection there was an increased proportion of capped viral RNAs in infected cells, the viral particles isolated from this condition contained equal ratios of capped and noncapped viral RNA, suggesting that there might be selective packaging of capped and noncapped RNAs. IMPORTANCE Rotaviruses have a genome composed of 11 segments of double-stranded RNA. Whether all 5' ends of the positive-sense genomic RNAs contained in the mature viral particles are modified by a cap structure is unknown. In this work, we characterized the relative proportions of capped and noncapped viral RNAs in rotavirus-infected cells and in viral particles by using a direct quantitative assay. We found that, independent of the relative proportions of capped/noncapped RNAs present in rotavirus-infected cells, there were similar proportions of these two kinds of 5'-modified positive-sense RNAs in the viral particles.
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Capuzes de RNA , RNA Viral , Rotavirus , Vírion , 2',5'-Oligoadenilato Sintetase , Proteínas do Capsídeo/metabolismo , Endorribonucleases/metabolismo , Capuzes de RNA/análise , Capuzes de RNA/química , Capuzes de RNA/metabolismo , RNA de Cadeia Dupla/genética , RNA de Cadeia Dupla/metabolismo , RNA Viral/química , RNA Viral/genética , RNA Viral/metabolismo , Rotavirus/genética , Rotavirus/metabolismo , Vírion/genética , Vírion/metabolismo , Replicação ViralRESUMO
Viral gastroenteritis has a global distribution and represents a high risk for vulnerable population and children under 5 years due to acute diarrhea, fever and dehydration. Human astroviruses (HAstV) have been identified as the third most important cause of viral gastroenteritis in pediatric and immunocompromised patients. Furthermore, HAstV has been reported in biopsies taken from patients with encephalitis, meningitis and acute respiratory infection, yet it is not clear how the virus reaches these organs. In this work we have tested the possibility that the released astrovirus particles could be associated with extracellular vesicles. Comparison between vesicles purified from HAstV Yuc8 infected and mock-infected cells showed that infection enhances production of vesicles larger than 150 nm. These vesicles contain CD63 and Alix, two markers of vesicular structures. Almost 70% of the extracellular virus present in clarified supernatant at 18 h postinfection was found associated with vesicular membranes, and this association facilitates cell infection in the absence of trypsin activation and protects virions from neutralizing antibodies. Our findings suggest a new pathway for HAstV spread and might represent an explanation for the extra-intestinal presence of some astrovirus strains. IMPORTANCE Astroviruses are an important cause of diarrhea in vulnerable population, particularly children; recently some reports have found these viruses in extra-intestinal organs, including the central nervous system, causing unexpected clinical disease. In this work, we found that human astrovirus strain Yuc8 associates with extracellular vesicles, possibly during or after their cell egress. The association with vesicles doubled astrovirus infectivity in less susceptible cells and rendered virus particles insensitive to neutralization by antibodies. These data suggest that extracellular vesicles could represent a novel pathway for astrovirus to disseminate outside the gastrointestinal tract.
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Infecções por Astroviridae , Vesículas Extracelulares , Gastroenterite , Mamastrovirus , Anticorpos Neutralizantes , Infecções por Astroviridae/imunologia , Infecções por Astroviridae/virologia , Vesículas Extracelulares/virologia , Gastroenterite/virologia , Humanos , Mamastrovirus/imunologiaRESUMO
Human astrovirus is an important cause of viral gastroenteritis worldwide. Young children, the elderly, and the immunocompromised are especially at risk for contracting severe disease. However, no vaccines exist to combat human astrovirus infection. Evidence points to the importance of antibodies in protecting healthy adults from reinfection. To develop an effective subunit vaccine that broadly protects against diverse astrovirus serotypes, we must understand how neutralizing antibodies target the capsid surface at the molecular level. Here, we report the structures of the human astrovirus capsid spike domain bound to two neutralizing monoclonal antibodies. These antibodies bind two distinct conformational epitopes on the spike surface. We add to existing evidence that the human astrovirus capsid spike contains a receptor-binding domain and demonstrate that both antibodies neutralize human astrovirus by blocking virus attachment to host cells. We identify patches of conserved amino acids which overlap or border the antibody epitopes and may constitute a receptor-binding site. Our findings provide a basis for developing therapies to prevent and treat human astrovirus gastroenteritis. IMPORTANCE Human astroviruses infect nearly every person in the world during childhood and cause diarrhea, vomiting, and fever. Despite the prevalence of this virus, little is known about how antibodies block astrovirus infection. Here, we determined the crystal structures of the astrovirus capsid protein in complex with two virus-neutralizing antibodies. We show that the antibodies bind to two distinct sites on the capsid spike domain, however, both antibodies block virus attachment to human cells. Importantly, our findings support the use of the human astrovirus capsid spike as an antigen in a subunit-based vaccine to prevent astrovirus disease.
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Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Infecções por Astroviridae/imunologia , Infecções por Astroviridae/virologia , Capsídeo/imunologia , Epitopos/imunologia , Mamastrovirus/imunologia , Sequência de Aminoácidos , Anticorpos Neutralizantes/química , Anticorpos Antivirais/química , Afinidade de Anticorpos/imunologia , Proteínas do Capsídeo/química , Proteínas do Capsídeo/imunologia , Epitopos/química , Interações Hospedeiro-Patógeno/imunologia , Humanos , Modelos Moleculares , Conformação Molecular , Ligação Proteica , Relação Estrutura-Atividade , Ligação ViralRESUMO
Human astrovirus VA1 has been associated with neurological disease in immunocompromised patients, and its recent propagation in cell culture has opened the possibility to study its biology. Unlike classical human astroviruses, VA1 growth was found to be independent of trypsin during virus replication in vitro. In this work, we show that despite its independence on trypsin activation for cell infection, the VA1 capsid precursor protein, of 86 kDa (VP86), is processed intracellularly, and this proteolytic processing is important for astrovirus VA1 infectivity. Antibodies raised against different regions of the capsid precursor showed that the polyprotein can be processed starting at either its amino- or carboxy-terminal end, and they allowed us to identify those proteins of about 33 (VP33) and 38 (VP38) kDa constitute the core and the spike proteins of the mature infectious virus particles, respectively. The amino-terminal end of the spike protein was found to be Thr-348. Whether the protease involved in intracellular cleavage of the capsid precursor is of viral or cellular origin remains to be determined, but the cleavage is independent of caspases. Also, trypsin is able to degrade the capsid precursor but has no effect on VP33 and VP38 proteins when assembled into virus particles. These studies provide the basis for advancement of the knowledge of astrovirus VA1 cell entry and replication. IMPORTANCE Human astrovirus VA1 has been associated with neurological disease in immunocompromised patients. Its recent propagation in cell culture has facilitated the study of its biology. In this work, we show that despite the ability of this virus to grow in the absence of trypsin, a marked feature of human classical astroviruses, the capsid precursor protein of astrovirus VA1 is cleaved intracellularly to yield the mature infectious particles, formed by two polypeptides, VP33 that constitutes the core domain of the virus particle, and VP38 that forms the spike of the virus. These studies provide a platform to advance our knowledge on astrovirus VA1 cell entry and replication.
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Infecções por Astroviridae , Proteínas do Capsídeo , Mamastrovirus , Precursores de Proteínas , Infecções por Astroviridae/virologia , Células CACO-2 , Capsídeo/metabolismo , Proteínas do Capsídeo/metabolismo , Humanos , Espaço Intracelular/virologia , Mamastrovirus/fisiologia , Precursores de Proteínas/metabolismo , Tripsina/metabolismoRESUMO
BACKGROUND: This study aims to identify which risk factors are associated with the appearance of an incisional hernia in a stoma site after its closure. This in the sake of identifying which patients would benefit from a preventative intervention and thus start implementing a cost-effective protocol for prophylactic mesh placement in high-risk patients. METHODS: A systematic review of PubMed, Cochrane library, and ScienceDirect was performed according to PRISMA guidelines. Studies reporting incidence, risk factors, and follow-up time for appearance of incisional hernia after stoma site closure were included. A fixed-effects and random effects models were used to calculate odds ratios' estimates and standardized mean values with their respective grouped 95% confidence interval. This to evaluate the association between possible risk factors and the appearance of incisional hernia after stoma site closure. RESULTS: Seventeen studies totaling 2899 patients were included. Incidence proportion between included studies was of 16.76% (CI95% 12.82; 21.62). Out of the evaluated factors higher BMI (p = 0.0001), presence of parastomal hernia (p = 0.0023), colostomy (p = 0,001), and end stoma (p = 0.0405) were associated with the appearance of incisional hernia in stoma site after stoma closure, while malignant disease (p = 0.0084) and rectum anterior resection (p = 0.0011) were found to be protective factors. CONCLUSIONS: Prophylactic mesh placement should be considered as an effective preventative intervention in high-risk patients (obese patients, patients with parastomal hernia, colostomy, and end stoma patients) with the goal of reducing incisional hernia rates in stoma site after closure while remaining cost-effective.
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Hérnia Incisional , Estomas Cirúrgicos , Humanos , Hérnia Incisional/epidemiologia , Hérnia Incisional/etiologia , Hérnia Incisional/prevenção & controle , Telas Cirúrgicas/efeitos adversos , Estomas Cirúrgicos/efeitos adversos , Colostomia/efeitos adversos , Fatores de RiscoRESUMO
The purpose of this research is to analyse the evolution and trends of research into digital pedagogy in higher education through the application of bibliometric analysis and systematic review of scientific output. For the bibliometric analysis, the built-in functions of WoS were used, including Analyze results and Citation report. The VOSviewer software was employed to construct bibliometric maps. The analysis focuses on studies about digitalisation, university education and education quality, three categories that are grouped around digital pedagogies and methodologies. The sample contains 242 scientific publications, including articles (65.7%), publications published in the United States (17.7%) and publications financed by the European Commission (3.71%). Barber, W., and Lewin, C., are the authors with the greatest impact. The scientific output forms three networks: the "social network" (2000-2010), the "digitalisation network" (2011-2015) and the "network of the expansion of digital pedagogy" (2016-2023). The most-mature research (2005-2009) concerns the integration of technologies in education. The research with the greatest impact (2020-2022) looks at digital pedagogy and its implementation during the situation created by COVID-19. This research shows that digital pedagogy has come a long way over the last twenty years, but it is at the same time a topical area today. The paper opens up future paths for research such as the development of more-flexible pedagogies that can be adapted to different pedagogical scenarios.
RESUMO
BACKGROUND: SARS-CoV-2 infections have a wide spectrum of clinical manifestations whose causes are not completely understood. Some human conditions predispose to severe outcome, like old age or the presence of comorbidities, but many other facets, including coinfections with other viruses, remain poorly characterized. METHODS: In this study, the eukaryotic fraction of the respiratory virome of 120 COVID-19 patients was characterized through whole metagenomic sequencing. RESULTS: Genetic material from respiratory viruses was detected in 25% of all samples, whereas human viruses other than SARS-CoV-2 were found in 80% of them. Samples from hospitalized and deceased patients presented a higher prevalence of different viruses when compared to ambulatory individuals. Small circular DNA viruses from the Anneloviridae (Torque teno midi virus 8, TTV-like mini virus 19 and 26) and Cycloviridae families (Human associated cyclovirus 10), Human betaherpesvirus 6, were found to be significantly more abundant in samples from deceased and hospitalized patients compared to samples from ambulatory individuals. Similarly, Rotavirus A, Measles morbillivirus and Alphapapilomavirus 10 were significantly more prevalent in deceased patients compared to hospitalized and ambulatory individuals. CONCLUSIONS: Results show the suitability of using metagenomics to characterize a broader peripheric virological landscape of the eukaryotic virome in SARS-CoV-2 infected patients with distinct disease outcomes. Identified prevalent viruses in hospitalized and deceased patients may prove important for the targeted exploration of coinfections that may impact prognosis.
Assuntos
COVID-19 , Coinfecção , Vírus , Humanos , SARS-CoV-2/genética , Coinfecção/epidemiologia , Vírus/genética , DNA Circular , Índice de Gravidade de DoençaRESUMO
Proliferative nodules (PNs) are benign nodular proliferation of melanocytes occurring within congenital melanocytic naevi (CMN). Differential diagnosis between PN and melanoma is challenging for clinicians and pathologists. We describe the case of a 9-month-old boy who developed multiple nodules arising in a medium-sized CMN. Clinically, pink papules were observed, with dotted vessels on dermoscopy, suggesting spitzoid PN. On histopathological examination, the dermoscopic findings correlated with the vertical vessels of a spitzoid PN. Dermoscopy could be a useful tool to differentiate PN from melanoma. However, further studies describing the dermoscopic features of the different PN subtypes are needed. Histopathology remains the gold standard for definitive diagnosis aided by ancillary molecular tests such as fluorescence in situ hybridization or comparative genomic hybridization.
Assuntos
Melanoma , Nevo de Células Epitelioides e Fusiformes , Nevo Pigmentado , Neoplasias Cutâneas , Hibridização Genômica Comparativa , Diagnóstico Diferencial , Humanos , Hibridização in Situ Fluorescente , Lactente , Masculino , Melanoma/patologia , Nevo Pigmentado/diagnóstico por imagem , Neoplasias Cutâneas/patologiaRESUMO
Objective. The aims of this study are to compare 2 origins of adipose-derived mesenchymal stem cells (MSCs) (omentum and subcutaneous) from 2 pathologies (morbid obesity and cancer) vs healthy donors. Adipose tissue has revealed to be the ideal MSC source. However, in developing adipose-derived stem cells (ASCs) for clinical use, it is important to consider the effects of different fat depots and also the effect of donor variability. Methods. We isolated and characterized the membrane markers and differentiation capacities of ASCs obtained from patients with these diseases and different origin. During the culture period, we further analysed the cells' proliferation capacity in an in vitro assay as well as their secretome. Results. Adipose-derived stem cells isolated from obese and cancer patients have mesenchymal phenotype and similar cell proliferation as ASCs derived from healthy donors, some higher in cells derived from subcutaneous fat. However, cells from these 2 types of patients do not have the same differentiation potential, especially in cancer patients from omentum, and exhibit distinct secretion of both pro-inflammatory and regulatory cytokines, which could explain the differences in use due to origin as well as pathology associated with the donor. Conclusion. Subcutaneous and omentum ASCs are slightly different; omentum generates fewer cells but with greater anti-inflammatory capacity. Adipose-derived stem cells from patients with either obesity or cancer are slightly altered, which limits their therapeutic properties.