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Early neutralizing antibodies against hepatitis C virus (HCV) and CD8 + T cell effector responses can lead to viral clearance. However, these functions alone are not sufficient to protect patients against HCV infection, thus undefined additional antiviral immune mechanisms are required. In recent years, Fc-receptor-dependent antibody effector functions, particularly, antibody-dependent cellular phagocytosis (ADCP) were shown to offer immune protection against several RNA viruses. However, its development and clinical role in patients with HCV infection remain unknown. In this study, we found that patients with chronic GT1a or GT3a HCV infection had significantly higher concentrations of anti-envelope 2 (E2) antibodies, predominantly IgG1 subclass, than patients that cleared the viruses while the latter had antibodies with higher affinities. 97% of the patients with HCV had measurable ADCP of whom patients with chronic disease showed significantly higher ADCP than those who naturally cleared the virus. Epitope mapping studies showed that patients with antibodies that target antigenic domains on the HCV E2 protein that are known to associate with neutralization function are also strongly associated with ADCP, suggesting antibodies with overlapping/dual functions. Correlation studies showed that ADCP significantly correlated with plasma anti-E2 antibody levels and neutralization function regardless of clinical outcome and genotype of infecting virus, while a significant correlation between ADCP and affinity was only evident in patients that cleared the virus. These results suggest ADCP was mostly driven by antibody titer in patients with chronic disease while maintained in clearers due to the quality (affinity) of their anti-E2 antibodies despite having lower antibody titers.
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Hepacivirus , Hepatite C , Humanos , Anticorpos Anti-Hepatite C , Anticorpos Neutralizantes , Proteínas do Envelope Viral , Fagocitose , Doença CrônicaRESUMO
Phagocytic responses by effector cells to opsonized viruses have been recognized to play a key role in antiviral immunity. Limited data on coronavirus disease 2019 suggest that the role of Ab-dependent and -independent phagocytosis may contribute to the observed immunological and inflammatory responses; however, their development, duration, and role remain to be fully elucidated. In this study of 62 acute and convalescent patients, we found that patients with acute coronavirus disease 2019 can mount a phagocytic response to autologous plasma-opsonized Spike protein-coated microbeads as early as 10 d after symptom onset, while heat inactivation of this plasma caused 77-95% abrogation of the phagocytic response and preblocking of Fc receptors showed variable 18-60% inhibition. In convalescent patients, phagocytic response significantly correlated with anti-Spike IgG titers and older patients, while patients with severe disease had significantly higher phagocytosis and neutralization functions compared with patients with asymptomatic, mild, or moderate disease. A longitudinal subset of the convalescent patients over 12 mo showed an increase in plasma Ab affinity toward Spike Ag and preservation of phagocytic and neutralization functions, despite a decline in the anti-Spike IgG titers by >90%. Our data suggest that early phagocytosis is primarily driven by heat-liable components of the plasma, such as activated complements, while anti-Spike IgG titers account for the majority of observed phagocytosis at convalescence. Longitudinally, a significant increase in the affinity of the anti-Spike Abs was observed that correlated with the maintenance of both the phagocytic and neutralization functions, suggesting an improvement in the quality of the Abs.
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COVID-19 , Anticorpos Neutralizantes , Anticorpos Antivirais , Antivirais , Humanos , Imunoglobulina G , Receptores Fc , SARS-CoV-2 , Glicoproteína da Espícula de CoronavírusRESUMO
PURPOSE: Triple-negative invasive lobular carcinoma (TN-ILC) of breast cancer is a rare disease and the clinical outcomes and prognostic factors are not well-defined. METHODS: Women with stage I-III TN-ILC or triple-negative invasive ductal carcinoma (TN-IDC) of the breast undergoing mastectomy or breast-conserving surgery between 2010 and 2018 in the National Cancer Database were included. Kaplan-Meier curves and multivariate Cox proportional hazard regression were used to compare overall survival (OS) and evaluate prognostic factors. Multivariate logistic regression was performed to analyze the factors associated with pathological response to neoadjuvant chemotherapy. RESULTS: The median age at diagnosis for women with TN-ILC was 67 years compared to 58 years in TN-IDC (p < 0.001). There was no significant difference in the OS between TN-ILC and TN-IDC in multivariate analysis (HR 0.96, p = 0.44). Black race and higher TNM stage were associated with worse OS, whereas receipt of chemotherapy or radiation was associated with better OS in TN-ILC. Among women with TN-ILC receiving neoadjuvant chemotherapy, the 5-year OS was 77.3% in women with a complete pathological response (pCR) compared to 39.8% in women without any response. The odds of achieving pCR following neoadjuvant chemotherapy were significantly lower in women with TN-ILC compared to TN-IDC (OR 0.53, p < 0.001). CONCLUSION: Women with TN-ILC are older at diagnosis but have similar OS compared to TN-IDC after adjusting for tumor and demographic characteristics. Administration of chemotherapy was associated with improved OS in TN-ILC, but women with TN-ILC were less likely to achieve complete response to neoadjuvant therapy compared to TN-IDC.
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Neoplasias da Mama , Carcinoma Ductal de Mama , Carcinoma Lobular , Feminino , Humanos , Idoso , Neoplasias da Mama/patologia , Carcinoma Lobular/patologia , Prognóstico , Carcinoma Ductal de Mama/patologia , MastectomiaRESUMO
The role of N-acetylcysteine (NAC) in the treatment of acetaminophen induced acute liver injury (ALI) is well established but its role in non-acetaminophen induced ALI is still elusive. We conducted this meta-analysis to evaluate the role of NAC in non-acetaminophen induced ALI. We searched electronic databases for studies published till Oct 25, 2020. We used RevMan v5.4 software to analyze the data extracted from selected studies by using Covidence systematic review software. Outcome estimation was done using Odds Ratio (OR) with 95% confidence interval (CI). The heterogeneity in various studies was determined using the I2 test. A total of 11 studies were included in quantitative analysis. Use of NAC in non-acetaminophen induced ALI showed 53% reduction in mortality compared to standard of care (OR, 0.47; CI, 0.29-0.75) and reduced mean duration of hospital stay by 6.52 days (95% CI, -12.91 to -0.13). Similarly, the rate of encephalopathy was 59% lower in the treatment group (OR, 0.41; CI, 0.20-0.83). However, the risk of developing nausea and vomiting (OR, 3.99; CI, 1.42-11.19), and the need for mechanical ventilation (OR 3.88; CI, 1.14-13.29) were significantly higher in the treatment group. These findings conclude use of NAC decreases mortality and hepatic encephalopathy compared to standard of care in patients with non-acetaminophen induced ALI. Although there is an increased risk of nausea and vomiting with the use of NAC, the majority of adverse events are transient and minor.
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Acetilcisteína/uso terapêutico , Sequestradores de Radicais Livres/uso terapêutico , Falência Hepática Aguda/induzido quimicamente , Falência Hepática Aguda/tratamento farmacológico , Humanos , Tempo de Internação , Falência Hepática Aguda/mortalidade , Padrão de Cuidado , Taxa de SobrevidaRESUMO
BACKGROUND: Nepal is an endemic area for hepatitis E virus (HEV) epidemics. The research on viral hepatitis in Nepal is limited. METHODS: Serum samples from 170 patients presenting with symptoms of hepatitis were collected from April to May 2014 in Biratnagar, Nepal, and then transported to Xiamen, China, for further evaluation. All samples were tested for HEV RNA, HEV antigen, anti-HEV IgM, anti-HEV IgG and anti-HBc IgM, anti-HCV IgG, and anti-HAV IgM. RESULTS: Sixteen patients were identified as acute hepatitis E with the presence of ≥ 2 HEV acute phase markers (antigen, RNA, and anti-HEV IgM). HEV infection was the major cause of potential active viral hepatitis (59.2%, 16 of 27), followed by HBV (25.9%, 7 of 27, anti-HBc IgM positive), HAV (18.5%, 5 of 27, anti-HAV IgM positive), and HCV (3.7%, 1 of 27, anti-HCV antibodies). All 16 confirmed HE cases were positive for HEV antigen, while 5 cases were HEV RNA positive, as well as 15 anti-HEV IgM positive. The low positive rate of RNA might be related to the collection and/or the transportation of these samples. CONCLUSIONS: This study showed that HEV is a major cause of acute hepatitis in developing countries and regions. Application of immunoassay diagnostic kits, especially the HEV antigen tests, showed great potential for HE detection in these countries and regions.
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Países em Desenvolvimento , Vírus da Hepatite E/imunologia , Hepatite E/diagnóstico , Vírus da Hepatite E/genética , Humanos , NepalAssuntos
COVID-19 , SARS-CoV-2 , Teste para COVID-19 , Vírus Delta da Hepatite , Humanos , RNA Viral , Eliminação de Partículas ViraisRESUMO
BACKGROUND: Infection with the hepatitis E virus (HEV) can cause acute hepatitis in endemic areas in immune-competent hosts, as well as chronic infection in immune-compromised subjects in non-endemic areas. Most studies assessing HEV infection in HIV-infected populations have been performed in developed countries that are usually affected by HEV genotype 3. The objective of this study is to measure the prevalence and risk of acquiring HEV among HIV-infected individuals in Nepal. METHODS: We prospectively evaluated 459 Human Immunodeficiency Virus (HIV)-positive individuals from Nepal, an endemic country for HEV, for seroprevalence of HEV and assessed risk factors associated with HEV infection. All individuals were on antiretroviral therapy and healthy blood donors were used as controls. RESULTS: We found a high prevalence of HEV IgG (39.4%) and HEV IgM (15.3%) in HIV-positive subjects when compared to healthy HIV-negative controls: 9.5% and 4.4%, respectively (OR: 6.17, 95% CI 4.42-8.61, p < 0.001 and OR: 3.7, 95% CI 2.35-5.92, p < 0.001, respectively). Individuals residing in the Kathmandu area showed a significantly higher HEV IgG seroprevalance compared to individuals residing outside of Kathmandu (76.8% vs 11.1%, OR: 30.33, 95% CI 18.02-51.04, p = 0.001). Mean CD4 counts, HIV viral load and presence of hepatitis B surface antigen correlated with higher HEV IgM rate, while presence of hepatitis C antibody correlated with higher rate of HEV IgG in serum. Overall, individuals with HEV IgM positivity had higher levels of alanine aminotransferase (ALT) than IgM negative subjects, suggesting active acute infection. However, no specific symptoms for hepatitis were identified. CONCLUSIONS: HIV-positive subjects living in Kathmandu are at higher risk of acquiring HEV infection as compared to the general population and to HIV-positive subjects living outside Kathmandu.
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Coinfecção/epidemiologia , Infecções por HIV/complicações , Infecções por HIV/virologia , Hepatite E/complicações , Hepatite E/epidemiologia , Adulto , Alanina Transaminase/sangue , Aspartato Aminotransferases/sangue , Contagem de Linfócito CD4 , Coinfecção/sangue , Coinfecção/virologia , Feminino , Infecções por HIV/sangue , Anticorpos Anti-Hepatite/sangue , Hepatite E/sangue , Hepatite E/virologia , Vírus da Hepatite E , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Masculino , Pessoa de Meia-Idade , Nepal/epidemiologia , Prevalência , RNA Viral/sangue , Fatores de Risco , Estudos SoroepidemiológicosRESUMO
Pulmonary tuberculosis (PTB) is one of the major infectious diseases in developing countries. The objective of this study was to compare rapid diagnostics technique, GeneXpert MTB/RIF (GeneXpert) and Multiplex PCR assay (MPCR) targeting IS6110 segment and mpb64 gene for direct detection of Mycobacterium tuberculosis (MTB) in suspected PTB patients. A cross sectional study was carried among 105 sputum samples from suspected PTB patients to evaluate GeneXpert and Multiplex PCR who visited National Tuberculosis Center, Nepal. The patient's sputum samples were used directly for the GeneXpert whereas DNA extraction by CTAB method was followed to process the sample for MPCR. The sensitivity and specificity of GeneXpert and MPCR in smear positive cases was 78.6, 33.3, and 100.0%, 66.7%, respectively (P = 0.125). However, in smear negative cases sensitivity and specificity of both methods exhibited 90.9, 95.2, and 100.0%, 100.0% respectively (P = 0.625). Finally, the sensitivity and specificity of GeneXpert and MPCR were 82.9, 95.3 and 100.0%, 98.5% respectively, (P = 0.549) in pulmonary cases. Comparatively, we observed higher sensitivity and specificity for MPCR than GeneXpert for both smear positive and negative samples. Thus, we recommend MPCR alongside GeneXpert for the better diagnostic accuracy of PTB in a resource-limited country where tuberculosis is endemic.
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Técnicas de Diagnóstico Molecular/métodos , Reação em Cadeia da Polimerase Multiplex/métodos , Mycobacterium tuberculosis/isolamento & purificação , Tuberculose Pulmonar/diagnóstico , Antígenos de Bactérias/genética , Proteínas de Bactérias/genética , Estudos Transversais , Elementos de DNA Transponíveis , Humanos , Mycobacterium tuberculosis/genética , Nepal , Sensibilidade e Especificidade , Escarro/microbiologiaRESUMO
BACKGROUND: TLR8 assists in antiviral approach by producing Type 1 INF via MyD88 dependent IRF7 pathway. However, over expression of INFα/ß molecule poses threat by developing tolerance in chronic infection cases and enhancing inflammatory response. Here we report a bi-specific siRNA based complex which differentially activates and silences the TLR8 and MYD88 respectively in a negatively regulated fashion. RESULTS: Outer membrane vesicle from Escherichia coli used for siRNA delivery was observed more efficient when attached with invasive protein Ail along with OmpA (P<0.001) in HEK293-TLR8 cell line. siRNA complexed with p19 protein was efficient in activating TLR8, confirmed by the increment of INFß molecules (P<0.001) in HEK293-TLR8 compared to its counterpart. Fusion of lipid bilayer of endosomal compartment was significant at pH 4.5 when fusogenic peptides (diINF-7) were incubated in membrane vesicle, thus facilitating the escape of siRNA complex to the host cytoplasm in order to silence MyD88 transcript (P<0.001). CONCLUSIONS: We investigated the activation of TLR8 by bi-specific si-RNA for the production of INFß. In the same setting we showed that bi-specific si-RNA was able to silence MyD88 transcript in a delayed manner. For the cases of auto immune disease and inflammation where over activation of endosomal TLRs poses serious threat, bi specific siRNA could be used as negative feedback controlled system.
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Retroalimentação Fisiológica , RNA Interferente Pequeno/metabolismo , Receptor 8 Toll-Like/metabolismo , Lipossomas Unilamelares/metabolismo , Proteínas da Membrana Bacteriana Externa/metabolismo , Morte Celular , Endocitose , Endossomos/metabolismo , Escherichia coli/metabolismo , Inativação Gênica , Células HEK293 , Humanos , Concentração de Íons de Hidrogênio , Interferon beta/metabolismo , Ligantes , Fusão de Membrana , Fator 88 de Diferenciação Mieloide/metabolismo , Periplasma/metabolismo , Transporte Proteico , Proteínas Virais/metabolismo , Fatores de Virulência/metabolismoRESUMO
BACKGROUND: Widal test, which has poor predictive outcomes in predominant typhoid population, is not standard enough to predict accurate diagnosis. This study aims to compare the diagnostic accuracy of Widal test to ELISA using blood culture as gold standard. METHODS: The blood samples were collected in Capital Hospital, Kathmandu, Nepal from febrile patients having ≥48 h fever in 3 years study period for blood culture, Widal test and IgG-IgM ELISA. RESULTS: Amongst 1371 febrile cases, 237 were Salmonella typhi positive to blood culture and 71.4 % typhoid fever patient were of 46-60 years old with male to female ratio of 2:1. Blood culture confirmed patients had ≥1:40 anti-TH and anti-TO titre in 45.56 % (n = 108) and 43.88 % (n = 104) patients respectively. The sensitivity and specificity of IgG (0.96 and 0.95) and IgM (0.95 and 0.94) at 95 % confidence level were significant compared to Widal anti-TH (0.72 and 0.58) and TO (0.80 and 0.51) test (p value, 0.038) at titre level ≥1:200. Further the PPV of Widal TH and TO (0.38 and 0.23) was low compared to IgG and IgM ELISA (0.78 and 0.77) (p value, 0.045). CONCLUSION: Widal test is not sensitive enough for an endemic setting like Nepal and thus should be either replaced with more accurate test like ELISA or follow an alternative diagnostic methodology.
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Ensaio de Imunoadsorção Enzimática/métodos , Febre Tifoide/diagnóstico , Adolescente , Adulto , Idoso , Testes de Aglutinação/métodos , Anticorpos Antibacterianos/sangue , Técnicas Bacteriológicas , Sangue/microbiologia , Criança , Pré-Escolar , Feminino , Hospitais , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Nepal , Salmonella typhi/imunologia , Salmonella typhi/patogenicidade , Sensibilidade e Especificidade , Febre Tifoide/microbiologia , Adulto JovemRESUMO
OBJECTIVES: Scrub typhus is an emerging infectious disease in Asia caused by Orientia tsutsugamushi (Ot). From Nepal, only scant data on the genetic epidemiology of this agent is available, and determinants of immunoregulation are poorly understood. METHODS: Patients (n = 238) referred to the National Public Health Laboratory (Kathmandu, Nepal) from all over Nepal for suspected scrub typhus were enrolled upon positive immunoglobulin (Ig)M testing between July and October 2015. From Ot 16S and 47 kD polymerase chain reaction (PCR)-positive samples, the variable domain I of the 56 kD gene was sequenced and phylogenetically analyzed. T helper (Th) cell-associated cytokines (n = 13) and chemokines (n = 12) were quantified by multiplex bead arrays. RESULTS: In 93/238 (39.1%) IgM-positive samples, Ot DNA was detected by quantitative PCR. Phylogenetic analysis of 56 kD sequences revealed seven distinct clusters, six of them with high homologies to strains detected in other countries. The Th1-related cytokines interferon-γ and C-X-C motif chemokine ligand 10 were strongly upregulated and correlated with bacteremia, while levels of Th2-associated chemokines were reduced. Bacteremia also correlated with concentrations of interleukin (IL)-6 and IL-10 but not tumor necrosis factor-α. CONCLUSION: We identified a considerable genetic heterogeneity of human-pathogenic Ot strains circulating in Nepal. Acute Nepalese scrub typhus patients showed strong Th1 but impaired Th2 responses, especially on the chemokine level.
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Orientia tsutsugamushi , Tifo por Ácaros , Humanos , Tifo por Ácaros/epidemiologia , Nepal/epidemiologia , Estudos Transversais , Orientia , Filogenia , Orientia tsutsugamushi/genética , Citocinas/genética , Imunoglobulina MRESUMO
Australia experienced widespread COVID-19 outbreaks from infection with the SARS-CoV-2 Delta variant between June 2021 and February 2022. A 17-nucleotide frameshift-inducing deletion in ORF7a rapidly became represented at the consensus level (Delta-ORF7aΔ17del) in most Australian outbreak cases. Studies from early in the COVID-19 pandemic suggest that frameshift-inducing deletions in ORF7a do not persist for long in the population; therefore, Delta-ORF7aΔ17del genomes should have disappeared early in the Australian outbreak. In this study, we conducted a retrospective analysis of global Delta genomes to characterise the dynamics of Delta-ORF7aΔ17del over time, determined the frequency of all ORF7a deletions worldwide, and compared global trends with those of the Australian Delta outbreak. We downloaded all GISAID clade GK Delta genomes and scanned them for deletions in ORF7a. For each deletion we identified, we characterised its frequency, the number of countries it was found in, and how long it persisted. Of the 4,018,216 Delta genomes identified globally, 134,751 (~3.35%) possessed an ORF7a deletion, and ORF7aΔ17del was the most common. ORF7aΔ17del was the sole deletion in 28,014 genomes, of which 27,912 (~99.6%) originated from the Australian outbreak. During the outbreak, ~87% of genomes were Delta-ORF7aΔ17del, and genomes with this deletion were sampled until the outbreak's end. These data demonstrate that, contrary to suggestions early in the COVID-19 pandemic, genomes with frameshifting deletions in ORF7a can persist over long time periods. We suggest that the proliferation of Delta-ORF7aΔ17del genomes was likely a chance founder effect. Nonetheless, the frequency of ORF7a deletions in SARS-CoV-2 genomes worldwide suggests they might have some benefit for virus transmission.
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COVID-19 , SARS-CoV-2 , Humanos , Austrália/epidemiologia , COVID-19/epidemiologia , Surtos de Doenças , Pandemias , Estudos Retrospectivos , SARS-CoV-2/genéticaRESUMO
Nepal is an endemic country for dengue infection with rolling of every 3 year's clear cyclic outbreaks with exponential growth since 2019 outbreak and the virus gearing towards the non-foci temperate hill regions. However, the information regarding circulating serotype and genotype is not frequent. This research discusses on the clinical features, diagnosis, epidemiology, circulating serotype and genotype among 61 dengue suspected cases from different hospitals of Nepal during the window period 2017-2018 between the two outbreaks of 2016 and 2019. E-gene sequences from PCR positive samples were subjected to phylogenetic analysis under time to most recent common ancestor tree using Markov Chain Monte Carlo (MCMC) and BEAST v2.5.1. Both evolution and genotypes were determined based on the phylogenetic tree. Serotyping by Real-time PCR and Nested PCR showed the co-circulation of all the 3 serotypes of dengue in the year 2017 and only DENV-2 in 2018. Genotype V for DENV-1 and Cosmopolitan Genotype IVa for DENV-2 were detected. The detected Genotype V of DENV-1 in Terai was found close to Indian genotype while Cosmopolitan IVa of DENV-2 found spreading to geographically safe hilly region (now gripped to 9 districts) was close to South-East Asia. The genetic drift of DENV-2 is probably due to climate change and rapid viral evolution which could be a representative model for high altitude shift of the infection. Further, the increased primary infection indicates dengue venturing to new populations. Platelets count together with Aspartate transaminase and Aalanine transaminase could serve as important clinical markers to support clinical diagnosis. The study will support future dengue virology and epidemiology in Nepal.
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Vírus da Dengue , Dengue , Humanos , Dengue/diagnóstico , Dengue/epidemiologia , Vírus da Dengue/genética , Filogenia , Nepal/epidemiologia , Surtos de Doenças , Sorogrupo , GenótipoRESUMO
Purpose: Triple-negative invasive lobular carcinoma (TN-ILC) of breast cancer is a rare disease and the clinical outcomes and prognostic factors are not well-defined. Methods: Women with stage I-III TN-ILC or triple-negative invasive ductal carcinoma (TN-IDC) of the breast undergoing mastectomy or breast-conserving surgery between 2010 and 2018 in the National Cancer Database were included. Kaplan-Meier curves and multivariate Cox proportional hazard regression were used to compare overall survival (OS) and evaluate prognostic factors. Multivariate logistic regression was performed to analyze the factors associated with pathological response to neoadjuvant chemotherapy. Results: The median age at diagnosis for women with TN-ILC was 67 years compared to 58 years in TN-IDC (p<0.001). There was no significant difference in the OS between TN-ILC and TN-IDC in multivariate analysis (HR 0.96, p=0.44). Black race and higher TNM stage were associated with worse OS, whereas receipt of chemotherapy or radiation was associated with better OS in TN-ILC. Among women with TN-ILC receiving neoadjuvant chemotherapy, the 5-year OS was 77.3% in women with a complete pathological response (pCR) compared to 39.8% in women without any response. The odds of achieving pCR following neoadjuvant chemotherapy were significantly lower in women with TN-ILC compared to TN-IDC (OR 0.53, p<0.001). Conclusion: Women with TN-ILC are older at diagnosis but have similar OS compared to TN-IDC after adjusting for tumor and demographic characteristics. Administration of chemotherapy was associated with improved OS in TN-ILC, but women with TN-ILC were less likely to achieve complete response to neoadjuvant therapy compared to TN-IDC.
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Objective: Class III obesity (body mass index [BMI] ≥ 40 kg m-2) significantly impairs the immune response to SARS-CoV-2 vaccination. However, the effect of an elevated BMI (≥ 25 kg m-2) on humoral immunity to SARS-CoV-2 infection and COVID-19 vaccination remains unclear. Methods: We collected blood samples from people who recovered from SARS-CoV-2 infection approximately 3 and 13 months of post-infection (noting that these individuals were not exposed to SARS-CoV-2 or vaccinated in the interim). We also collected blood samples from people approximately 5 months of post-second dose COVID-19 vaccination (the majority of whom did not have a prior SARS-CoV-2 infection). We measured their humoral responses to SARS-CoV-2, grouping individuals based on a BMI greater or less than 25 kg m-2. Results: Here, we show that an increased BMI (≥ 25 kg m-2), when accounting for age and sex differences, is associated with reduced antibody responses after SARS-CoV-2 infection. At 3 months of post-infection, an elevated BMI was associated with reduced antibody titres. At 13 months of post-infection, an elevated BMI was associated with reduced antibody avidity and a reduced percentage of spike-positive B cells. In contrast, no significant association was noted between a BMI ≥ 25 kg m-2 and humoral immunity to SARS-CoV-2 at 5 months of post-secondary vaccination. Conclusions: Taken together, these data showed that elevated BMI is associated with an impaired humoral immune response to SARS-CoV-2 infection. The impairment of infection-induced immunity in individuals with a BMI ≥ 25 kg m-2 suggests an added impetus for vaccination rather than relying on infection-induced immunity.
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Human immunodeficiency virus type 1 (HIV-1)-neutralizing antibodies (nAbs) that prevent infection are the main goal of HIV vaccine discovery. But as no nAb-eliciting vaccines are yet available, only data from HIV-1 neutralizers-persons with HIV-1 who naturally develop broad and potent nAbs-can inform about the dynamics and durability of nAb responses in humans, knowledge which is crucial for the design of future HIV-1 vaccine regimens. To address this, we assessed HIV-1-neutralizing immunoglobulin G (IgG) from 2,354 persons with HIV-1 on or off antiretroviral therapy (ART). Infection with non-clade B viruses, CD4+ T cell counts <200 µl-1, being off ART and a longer time off ART were independent predictors of a more potent and broad neutralization. In longitudinal analyses, we found nAb half-lives of 9.3 and 16.9 years in individuals with no- or low-level viremia, respectively, and 4.0 years in persons who newly initiated ART. Finally, in a potent HIV-1 neutralizer, we identified lower fractions of serum nAbs and of nAb-encoding memory B cells after ART initiation, suggesting that a decreasing neutralizing serum activity after antigen withdrawal is due to lower levels of nAbs. These results collectively show that HIV-1-neutralizing responses can persist for several years, even at low antigen levels, suggesting that an HIV-1 vaccine may elicit a durable nAb response.
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Vacinas contra a AIDS , Infecções por HIV , HIV-1 , Humanos , Anticorpos Anti-HIV , Anticorpos Neutralizantes , Replicação ViralAssuntos
Vírus da Hepatite E , Hepatite E/virologia , Feminino , Infecções por HIV , Hepatite B , Humanos , Masculino , NepalRESUMO
During health emergencies such as the COVID-19 pandemic, healthcare workers face numerous ethical challenges while catering to the needs of patients in healthcare settings. Although the data recapitulating high-income countries ethics frameworks are available, the challenges faced by clinicians in resource-limited settings of low- and middle-income countries are not discussed widely due to a lack of baseline data or evidence. The Nepali healthcare system, which is chronically understaffed and underequipped, was severely affected by the COVID-19 pandemic in its capacity to manage health services and resources for needy patients, leading to ethical dilemmas and challenges during clinical practice. This study aimed to develop a standard guideline that would address syndemic ethical dilemmas during clinical care of COVID-19 patients who are unable to afford standard-of-care. A mixed method study was conducted between February and June of 2021 in 12 government designated COVID-19 treatment hospitals in central Nepal. The draft guideline was discussed among the key stakeholders in the pandemic response in Nepal. The major ethical dilemmas confronted by the study participants (50 healthcare professionals providing patient care at COVID-19 treatment hospitals) could be grouped into five major pillars of ethical clinical practice: rational allocation of medical resources, updated treatment protocols that guide clinical decisions, standard-of-care regardless of patient's economic status, effective communication among stakeholders for prompt patient care, and external factors such as political and bureaucratic interference affecting ethical practice. This living clinical ethics guideline, which has been developed based on the local evidence and case stories of frontline responders, is expected to inform the policymakers as well as the decision-makers positioned at the concerned government units. These ethics guidelines could be endorsed with revisions by the concerned regulatory authorities for the use during consequent waves of COVID-19 and other epidemics that may occur in the future. Other countries affected by the pandemic could conduct similar studies to explore ethical practices in the local clinical and public health context.
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Tratamento Farmacológico da COVID-19 , COVID-19 , COVID-19/epidemiologia , Ética Clínica , Medicina Baseada em Evidências , Serviços de Saúde , Humanos , Nepal , Pandemias , Guias de Prática Clínica como AssuntoRESUMO
Introduced in the 1970s to meet the academic needs of a growing number of students with relatively stagnant faculty, team-based learning (TBL) has revolutionized the modern classroom structure. Contrary to the traditional didactic model where the teacher assumes the central role and students are passive listeners, TBL participants are actively involved in the learning process. Teachers act as facilitators while the TBL participants work in groups to solve problems through engagement with their peers. The objective of the article is to conduct a systematic review on team-based learning using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guideline. The studies were searched in databases like PubMed®, Scopus®, Embase®, and PubMed Central® using appropriate keywords. Two authors screened the papers, and a third author resolved the conflicts. This was followed by a bibliographic review based on the references of the selected study and bias assessment using the Joanna Briggs Institute (JBI) critical appraisal tool. The team-based learning model is increasingly being used by different institutions globally. TBL and traditional lecture-based teaching outcomes revealed that TBL participants performed better in academic, clinical, and communication domains. In addition, TBL enhanced learners' engagement, collaborative spirit, and satisfaction. Our study results are similar to the prior meta-analysis and systematic review. Nevertheless, this systematic review remains more comprehensive, up-to-date, and inclusive thus far. Team-based learning is a pragmatic and superior approach to learning among health care professionals. It has resulted in better academic, clinical, and communication outcomes. This finding spans all the medical and allied professions studied in this systematic review.
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INTRODUCTION: The use of multiagent chemotherapy in acute lymphoblastic leukemia (ALL) has resulted in improvement in overall survival (OS), albeit to a different extent across various age groups. This large database study aims to assess the disparity in the utilization of chemotherapy in ALL in the real-world setting. MATERIALS AND METHODS: Using the Surveillance, Epidemiology, and End Results database, patients with ALL diagnosis from 2006 to 2016 were identified. Baseline characteristics were compared between the groups who did vs. did not receive chemotherapy using χ2 test. Multivariable logistic regression was used to evaluate the association between various sociodemographic factors and the receipt of chemotherapy in the entire cohort and in different age groups. RESULTS: Out of 16,196 patients, 1258 patients (8%) did not receive chemotherapy. There was a steady increase in the number of patients who did not receive chemotherapy with advancing age: 2.5% (0-18 years), 5.2% (19-40 years), 9.3% (41-65 years), and 36.2% (>65 years). There was an upward trend in the receipt of chemotherapy in patients >65 years over the last decade. In multivariate analysis, the likelihood of receiving chemotherapy decreased with advancing age, single or widowed status, low income and educational status, and lack of insurance. Insurance status was an independent predictor of receipt of chemotherapy across each age category. CONCLUSION: A significant proportion of patients >65 years do not receive chemotherapy in the United States. Age, marital status, income, education, and insurance status contribute to the disparity in utilization of chemotherapy.