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1.
J Viral Hepat ; 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39109700

RESUMO

Co-existing chronic hepatitis B virus (CHB) infection and metabolic dysfunction associated steatotic liver disease (MASLD) can exert complex effects on hepatic metabolism, requiring mechanistic study. CHB participants were assessed for MASLD and the impact of hepatic steatosis/metabolic syndrome (MetS) on novel viral and immunological markers. In this prospective, cohort study, untreated CHB subjects were assessed for liver disease by non-invasive tests (i.e. FibroScan, controlled attenuation parameter, CAP). Subjects were tested for cytokines and IFN-γ ELISPOT assay to HBV Surface (S) and Core (C) proteins. Standard HBV serological, exploratory biomarkers and deep sequencing of HBV S and C genes were performed. In 53 subjects (median age 45 years [SD = 10.6], 35% F, 56% Asian, 20% Black, 3% White), 94% (50) HBeAg negative, 63% genotype B/C, mean HBV DNA 3.2 log10 IU/mL (SD = 1.8), quantitative HBsAg 2.9 log10 IU/mL (SD = 1.2) and HBV pgRNA 2.1 log10 copies/mL (SD = 1.3). In enrolled subjects, the mean ALT was 41.9 U/L (SD = 24.0), FibroScan was 5.7 kPa (SD = 1.9) and CAP was 306.4 dB/m (SD = 49.0). The mean BMI was 28.2 kg/m2 (SD = 4.2), 20% (11/53) had diabetes, 35% (19/53) dyslipidaemia and 24% (13/53) hypertension. Subjects with MetS and steatosis showed lower HBV markers (p < .01), higher HBV S diversity (p = .02) and greater frequency of HBV variants associated with host-anti-viral immune escape. Pro-inflammatory cytokine levels and HBV-specific cellular responses were higher in participants with hepatic steatosis. In CHB, MASLD/hepatic steatosis was associated with HBV variants and systemic immune responses potentially impacting liver disease progression despite low-level viraemia.

2.
J Org Chem ; 88(16): 11392-11410, 2023 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-35926190

RESUMO

The oxidation of various aryl and aliphatic thiols with the commercially available and environmentally benign reagent Bobbitt's salt (1) has been investigated. The reaction affords the corresponding disulfide products in good to excellent yields (71-99%) and can be accomplished in water, methanol, or acetonitrile solvent. Moreover, the process is highly chemoselective, tolerating traditionally oxidation-labile groups such as free amines and alcohols. Combined experimental and computational studies reveal that the oxidation takes place via a polar two-electron process with concomitant and unexpected deoxygenation of the oxoammonium cation through homolysis of the weak N-O bond, differing from prototypical radical-based thiol couplings. This unusual consumption of the oxidant has significant implications for the development of new nitroxide-based radical traps for probing S-centered radicals, the advancement of new electrochemical or catalytic processes involving nitroxide/oxoammonium salt redox couples, and applications to biological systems.

3.
Front Med (Lausanne) ; 10: 1125139, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37877022

RESUMO

Background: Hepatitis B virus (HBV)/Hepatitis D Virus (HDV) co-infection increases the risk of severe liver disease compared to HBV mono-infection. Adaptive immune responses to HDV are weakly detectable, and the involvement of innate immunity in the progression of HDV-related liver fibrosis is suggested. We hypothesize that an overall innate immune activation in HBV/HDV co-infection plays a role in liver disease progression and also impacts virus specific T cell response. Methods: Sixteen HBV/HDV-co-infected-patients (median age 42y/7F/6 Asian/4 White/6 Black/15 HBeAg-) and 8 HBV monoinfected-patients (median age 39y/4F/4 Asian/3 Black/1 White/HBeAg-) with median follow-up of 5 years were enrolled. Liver fibrosis was assessed by liver stiffness measurement (LSM, FibroScan®). Proliferation of CD3 + CD4+ T cells in response to viral antigens using CFSE assays and cytokine secreting monocytes was analyzed by flow cytometry. Results: Of 16 HBV/HDV, 11 were HDV-RNA+ (HBV-DNA 0-1,040 IU/mL), 5/11 Interferon (IFN) + Nucleos/tide Analog (NA), 3/11 NA monotherapy, median ALT 77 U/L at the time of sample collection, median LSM of 9.8. In 5 HDV RNA-, median HBV DNA 65 IU/mL, 4/5 prior IFN and/or NA, ALT 31 U/L, and median LSM 8.5 kPa. In 8 HBV controls, median HBV-DNA, ALT, LSM was 69 IU/mL, 33 U/L,5 kPa, respectively. PBMC stimulation with HBV core antigen (HBcAg) and HDV antigen (HDAg) showed weaker CD3 + CD4 + T-cell proliferation in HDV-RNA+ vs. HDV RNA- and HBV-mono-infected patients (p < 0.05). In HDV-RNA+ patients, a correlation between ALT and TNF-α (r = 0.76, p = 0.008), higher IL-10 levels and increased proportion of CD14 + TNF-α+ cells were found. Conclusion: In summary, during HBV/HDV coinfection, HDV RNA+ patients had weaker HBV and HDV specific responses, associated with increased TNF-α + monocytes irrespective of IFN treatment.

4.
Front Microbiol ; 14: 1233178, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37645229

RESUMO

Introduction: Serum hepatitis B virus (HBV) RNA is a promising new biomarker to manage and predict clinical outcomes of chronic hepatitis B (CHB) infection. However, the HBV serum transcriptome within encapsidated particles, which is the biomarker analyte measured in serum, remains poorly characterized. This study aimed to evaluate serum HBV RNA transcript composition and proportionality by PCR-cDNA nanopore sequencing of samples from CHB patients having varied HBV genotype (gt, A to F) and HBeAg status. Methods: Longitudinal specimens from 3 individuals during and following pregnancy (approximately 7 months between time points) were also investigated. HBV RNA extracted from 16 serum samples obtained from 13 patients (73.3% female, 84.6% Asian) was sequenced and serum HBV RNA isoform detection and quantification were performed using three bioinformatic workflows; FLAIR, RATTLE, and a GraphMap-based workflow within the Galaxy application. A spike-in RNA variant (SIRV) control mix was used to assess run quality and coverage. The proportionality of transcript isoforms was based on total HBV reads determined by each workflow. Results: All chosen isoform detection workflows showed high agreement in transcript proportionality and composition for most samples. HBV pregenomic RNA (pgRNA) was the most frequently observed transcript isoform (93.8% of patient samples), while other detected transcripts included pgRNA spliced variants, 3' truncated variants and HBx mRNA, depending on the isoform detection method. Spliced variants of pgRNA were primarily observed in HBV gtB, C, E, or F-infected patients, with the Sp1 spliced variant detected most frequently. Twelve other pgRNA spliced variant transcripts were identified, including 3 previously unidentified transcripts, although spliced isoform identification was very dependent on the workflow used to analyze sequence data. Longitudinal sampling among pregnant and post-partum antiviral-treated individuals showed increasing proportions of 3' truncated pgRNA variants over time. Conclusions: This study demonstrated long-read sequencing as a promising tool for the characterization of the serum HBV transcriptome. However, further studies are needed to better understand how serum HBV RNA isoform type and proportion are linked to CHB disease progression and antiviral treatment response.

5.
Am J Cardiol ; 162: 111-115, 2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34903336

RESUMO

Cardiac arrhythmias have been observed in patients hospitalized with coronavirus disease (COVID-19). Most analyses of rhythm disturbances to date include cases of sinus tachycardia, which may not accurately reflect true cardiac dysfunction. Furthermore, limited data exist regarding the development of conduction disturbances in patients hospitalized with COVID-19. Hence, we performed a retrospective review and compared characteristics and outcomes for patients with versus without incident arrhythmia, excluding sinus tachycardia, as well as between those with versus without incident conduction disturbances. There were 27 of 173 patients (16%) hospitalized with COVID-19 who developed a new arrhythmia. Incident arrhythmias were associated with an increased risk of intensive care unit admission (59% vs 31%, p = 0.0045), intubation (56% vs 20%, p <0.0001), and inpatient death (41% vs 10%, p = 0.0002) without an associated increase in risk of decompensated heart failure or other cardiac issues. New conduction disturbances were found in 13 patients (8%). Incident arrhythmias in patients hospitalized with COVID-19 are associated with an increased risk of mortality, likely reflective of underlying COVID-19 disease severity more than intrinsic cardiac dysfunction. Conduction disturbances occurred less commonly and were not associated with adverse patient outcomes.


Assuntos
Arritmias Cardíacas/etiologia , COVID-19/complicações , Sistema de Condução Cardíaco/fisiopatologia , Hospitalização/estatística & dados numéricos , Pacientes Internados , SARS-CoV-2 , Idoso , Arritmias Cardíacas/epidemiologia , Arritmias Cardíacas/terapia , COVID-19/epidemiologia , COVID-19/terapia , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Estados Unidos/epidemiologia
6.
JACC Case Rep ; 4(10): 604-609, 2022 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-35615220

RESUMO

Patients with both a prosthetic aortic valve and prolonged left ventricular assist device support can develop rapid deterioration of their valve prosthesis. In patients with myocardial recovery who are undergoing explantation of their ventricular assist device, preoperative and intraoperative evaluation of the valve prosthesis should be performed to ensure adequate function. (Level of Difficulty: Advanced.).

7.
Gastro Hep Adv ; 1(1): 106-116, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-39129930

RESUMO

Background and Aims: The obesity epidemic has increased the risk of nonalcoholic fatty liver disease (NAFLD) in both the general and chronic hepatitis B (CHB) populations. Our study aims to determine the prevalence of NAFLD in patients with CHB based on controlled attenuation parameter (CAP) and the epidemiological, clinical, and virological factors associated with severe hepatic steatosis. Methods: The Canadian Hepatitis B Network cohort was utilized to provide a cross-sectional description of demographics, comorbidities, antiviral treatment, and hepatits B virus (HBV) tests. Liver fibrosis and steatosis were measured by transient elastography and CAP, respectively. Any grade and severe steatosis were defined as CAP >248 and >280 dB/m, respectively. Advanced liver fibrosis was defined as transient elastography measurement >10.7 kPa. Results: In 1178 patients with CHB (median age: 47.4%, 57.7% males, 75.7% Asian, 13% African, 6.5% White, 86% HBV e antigen negative, median HBV DNA of 2.44 log10IU/mL, 42.7% receiving treatment), the prevalence of any grade and severe steatosis was 53% and 36%, respectively. In the multivariate analysis, obesity was a significant predictor for severe steatosis (adjusted odds ratio: 5.046, 95% confidence interval: 1.22-20.93). Severe steatosis was a determinant associated with viral load (adjusted odds ratio: 0.385, 95% confidence interval: 0.20-0.75, P < .01; r = -0.096, P = .007) regardless of antiviral therapy, age, and alanine aminotransferase levels. Conclusion: In this large multiethnic CHB population, hepatic steatosis is common. Severe steatosis is independently associated with higher fibrosis, but negatively with HBV DNA, regardless of antiviral therapy history.

8.
Am J Cardiol ; 128: 161-162, 2020 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-32650913

RESUMO

We describe an 84-year-old man who presented with hemoptysis and acute blood loss anemia due to a pulmonary artery pseudoaneurysm (PAP). The etiology of his PAP was thought to be an abandoned epicardial defibrillator patch that was implanted at age 55. To our knowledge, PAP has never been reported as a possible complication of an abandoned epicardial defibrillator patch.


Assuntos
Falso Aneurisma/diagnóstico por imagem , Desfibriladores Implantáveis , Corpos Estranhos/diagnóstico por imagem , Artéria Pulmonar/diagnóstico por imagem , Idoso de 80 Anos ou mais , Anemia/etiologia , Anemia/terapia , Falso Aneurisma/etiologia , Falso Aneurisma/cirurgia , Angiografia Digital , Transfusão de Sangue , Procedimentos Endovasculares , Corpos Estranhos/complicações , Hemoptise/etiologia , Hemoptise/cirurgia , Humanos , Masculino , Artéria Pulmonar/cirurgia , Tomografia Computadorizada por Raios X
9.
PLoS One ; 15(11): e0242577, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33211768

RESUMO

BACKGROUND: Occult hepatitis B (OHB) is a major concern in HIV infected patients as it associates with a high risk of HBV reactivation and disease progression. However, data on the prevalence of OHB among HIV positive patients in Ethiopia is lacking. This study aims to determine the prevalence of OHB in HBV/HIV co-infected patients from Gondar, Ethiopia. METHODS: A total of 308 consented HIV positive patients were recruited from the University of Gondar Teaching Hospital, Ethiopia. Clinical and demographic data of the participants were recorded. Plasma was tested for HBsAg and anti-HBc using commercial assays (Abbott Architect). In HBsAg negative anti-HBc positive patient samples, total DNA was isolated and amplified using nested PCR with primers specific to HBV polymerase, surface and pre-core/core regions, followed by Sanger sequencing and HBV mutational analysis using MEGA 7.0. RESULTS: Of the total study subjects, 62.7% were female, median age 38.4 years, interquartile range (IQR): 18-68, and 208 (67.5%) had lifestyle risk factors for HBV acquisition. Two hundred and ninety-one study subjects were HIV+/HBsAg-, out of which 115 (39.5%) were positive for anti-HBc. Occult hepatitis B was detected in 19.1% (22/115) of anti-HBc positive HIV patients. HBV genotype D was the predominant genotype (81%) among OHB positive patients. Mutations associated with HBV drug resistance, HBV reactivation, and HCC risk were detected in 23% (5/22), 14% (3/22) and 45.5% (10/22) of patients, respectively. CONCLUSION: This study found a high rate of occult hepatitis B in HIV patients. Further, high rates of mutations associated with HBV reactivation, drug resistance, and HCC risk were detected in these patients. These data highlighted the need for integrating OHB screening for proper management of liver diseases in HIV patients.


Assuntos
Coinfecção/epidemiologia , Infecções por HIV/epidemiologia , HIV-1 , Vírus da Hepatite B/isolamento & purificação , Hepatite B Crônica/epidemiologia , Adolescente , Adulto , Idoso , Coinfecção/sangue , Coinfecção/virologia , Comorbidade , Estudos Transversais , DNA Viral/sangue , Etiópia/epidemiologia , Feminino , Genótipo , Soropositividade para HIV/epidemiologia , Anticorpos Anti-Hepatite B/sangue , Antígenos de Superfície da Hepatite B/sangue , Vírus da Hepatite B/genética , Vírus da Hepatite B/fisiologia , Hepatite B Crônica/sangue , Hepatite B Crônica/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Filogenia , Prevalência , Fatores Socioeconômicos , Ativação Viral , Adulto Jovem
10.
J Clin Virol ; 111: 42-47, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30639847

RESUMO

BACKGROUND: Hepatitis B virus (HBV) flares have been reported due to alterations in the immune system during pregnancy. Recent studies in non-pregnant chronic hepatitis B (CHB) carriers have indicated that serum HBV RNA is a novel viral marker to assess treatment response and risk of disease flares. OBJECTIVES: To analyze serum HBV RNA levels in association with established HBV markers in pregnant and/or post-partum CHB carriers. STUDY DESIGN: In this prospective cohort study, serum and plasma were collected from 46 pregnant and/or post-partum CHB patients. Clinical data included demographics, hepatitis B e antigen (HBeAg) status (Abbott), quantitative hepatitis B s antigen (qHBsAg) levels (Abbott), HBV DNA (Abbott, sensitivity 10 IU/mL), alanine aminotransferase (ALT), liver stiffness measurement (LSM, post-partum), and treatment regime. Serum HBV total RNA and pre-genomic (pg)RNA were quantified using in-house assays, and HBV genotype was determined by direct population sequencing of HBV surface gene. Parametric and non-parametric statistical methods were used for analysis. RESULTS: In this study, we found that serum HBV total RNA levels correlated with the HBeAg status, HBV DNA, qHBsAg, ALT, and LSM while serum HBV pgRNA levels did not (p < 0.05, N = 46). Additionally, HBV total RNA & pgRNA levels increased, HBV DNA levels decreased, and qHBsAg levels remained unchanged throughout tenofovir disoproxil fumarate (TDF) treatment (N = 2). CONCLUSIONS: The associations between serum HBV total RNA with other validated markers indicates it may be a complementary HBV marker to monitor liver disease and HBV replication during pregnancy.


Assuntos
Vírus da Hepatite B/isolamento & purificação , RNA Viral/sangue , Carga Viral , Adulto , Biomarcadores/sangue , DNA Viral/sangue , Feminino , Genótipo , Antígenos de Superfície da Hepatite B/sangue , Antígenos E da Hepatite B/sangue , Hepatite B Crônica/virologia , Humanos , Gravidez , Estudos Prospectivos , RNA/sangue , Adulto Jovem
11.
Physiol Rep ; 6(12): e13748, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29932499

RESUMO

Large conductance calcium and voltage-activated potassium channels (BKCa ) are transmembrane proteins, ubiquitously expressed in the majority of organs, and play an active role in regulating cellular physiology. In the heart, BKCa channels are known to play a role in regulating the heart rate and protect it from ischemia-reperfusion injury. In vascular smooth muscle cells, the opening of BKCa channels results in membrane hyperpolarization which eventually results in vasodilation mediated by a reduction in Ca2+ influx due to the closure of voltage-dependent Ca2+ channels. Ex vivo studies have shown that BKCa channels play an active role in the regulation of the function of the majority of blood vessels. However, in vivo role of BKCa channels in cardiovascular function is not completely deciphered. Here, we have evaluated the rapid in vivo role of BKCa channels in regulating the cardiovascular function by using two well-established, rapid-acting, potent blockers, paxilline and iberiotoxin. Our results show that BKCa channels are actively involved in regulating the heart rate, the function of the left and right heart as well as major vessels. We also found that the effect on BKCa channels by blockers is completely reversible, and hence, BKCa channels can be exploited as potential targets for clinical applications for modulating heart rate and cardiac contractility.


Assuntos
Frequência Cardíaca/fisiologia , Subunidades alfa do Canal de Potássio Ativado por Cálcio de Condutância Alta/fisiologia , Função Ventricular/fisiologia , Animais , Velocidade do Fluxo Sanguíneo/fisiologia , Circulação Coronária/efeitos dos fármacos , Circulação Coronária/fisiologia , Ecocardiografia , Coração/diagnóstico por imagem , Frequência Cardíaca/efeitos dos fármacos , Indóis/farmacologia , Subunidades alfa do Canal de Potássio Ativado por Cálcio de Condutância Alta/antagonistas & inibidores , Masculino , Peptídeos/farmacologia , Bloqueadores dos Canais de Potássio/farmacologia , Artéria Pulmonar/diagnóstico por imagem , Artéria Pulmonar/efeitos dos fármacos , Artéria Pulmonar/fisiologia , Ratos Sprague-Dawley , Disfunção Ventricular Esquerda/induzido quimicamente , Disfunção Ventricular Esquerda/fisiopatologia , Função Ventricular/efeitos dos fármacos
14.
BMC Res Notes ; 7: 885, 2014 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-25486984

RESUMO

BACKGROUND: Aggregatibacter bacteria are a rare cause of endocarditis in adults. They are part of a group of organisms known as HACEK--Haemophilus, Aggregatibacter, Cardiobacter, Eikenella, and Kingella. Among these organisms, several Haemophilus species have been reclassified under the genus Aggregatibacter. Very few cases of Aggregatibacter endocarditis in patients with pacemaker devices have been reported. CASE PRESENTATION: We present here what we believe to be the first case of Aggregatibacter aphrophilus pacemaker endocarditis. A 62-year-old African American male with a medical history significant for dual-chamber pacemaker placement in 1996 for complete heart block with subsequent lead manipulation in 2007, presented to his primary care doctor with fever, chills, night sweats, fatigue, and ten-pound weight loss over a four-month period. Physical examination revealed a new murmur and jugular venous distension which prompted initiation of antibiotics for suspicion of endocarditis. Both sets of initial blood cultures were positive for A. aphrophilus. Transesophageal echocardiogram revealed vegetations on the tricuspid valve and the right ventricular pacemaker lead (Figure 1). This case highlights the importance of identifying rare causes of endocarditis and recognizing that treatment may not differ from the standard treatment for typical presentations. The patient received intravenous ceftriaxone for his endocarditis for a total of six weeks. Upon device removal, temporary jugular venous pacing wires were placed. After two weeks of antibiotic treatment and no clinical deterioration, a new permanent pacemaker was placed and the patient was discharged home. CONCLUSIONS: This is the first case of A. aphrophilus endocarditis in a patient with a permanent pacemaker. Our patient had no obvious risk factors other than poor dentition and a history of repeated pacemaker lead manipulation. This suggests that valvulopathies secondary to repeated lead manipulation can be clinically significant factors in morbidity and mortality in this patient population.


Assuntos
Aggregatibacter aphrophilus/isolamento & purificação , Endocardite Bacteriana/microbiologia , Marca-Passo Artificial , Aggregatibacter aphrophilus/patogenicidade , Antibacterianos/uso terapêutico , Ceftriaxona/uso terapêutico , Ecocardiografia Transesofagiana , Endocardite Bacteriana/diagnóstico por imagem , Endocardite Bacteriana/tratamento farmacológico , Humanos , Masculino , Pessoa de Meia-Idade
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