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1.
Annu Rev Cell Dev Biol ; 33: 343-368, 2017 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-28715909

RESUMO

Cells of all organisms survey problems during translation elongation, which may happen as a consequence of mRNA aberrations, inefficient decoding, or other sources. In eukaryotes, ribosome-associated quality control (RQC) senses elongation-stalled ribosomes and promotes dissociation of ribosomal subunits. This so-called ribosomal rescue releases the mRNA for degradation and allows 40S subunits to be recycled for new rounds of translation. However, the nascent polypeptide chains remain linked to tRNA and associated with the rescued 60S subunits. As a final critical step in this pathway, the Ltn1/Listerin E3 ligase subunit of the RQC complex (RQCc) ubiquitylates the nascent chain, which promotes clearance of the 60S subunit while simultaneously marking the nascent chain for elimination. Here we review the ribosomal stalling and rescue steps upstream of the RQCc, where one witnesses intersection with cellular machineries implicated in translation elongation, translation termination, ribosomal subunit recycling, and mRNA quality control. We emphasize both recent progress and future directions in this area, as well as examples linking ribosomal rescue with the production of Ltn1-RQCc substrates.


Assuntos
Biossíntese de Proteínas , Proteínas/metabolismo , Ribossomos/metabolismo , Animais , Humanos , Subunidades Proteicas/metabolismo , Especificidade por Substrato , Ubiquitinação
2.
J Med Virol ; 96(7): e29823, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39039862

RESUMO

A transfusion-transmitted hepatitis B virus (HBV) infection caused by blood only positive for anti-hepatitis B surface antigen (anti-HBs) was reported. Occult HBV infection (OBI) with sole anti-HBs among blood donors is an issue. The incidence of HBV infection among repeat blood donors was investigated with a detailed HBV infection phase, focusing on the influence of anti-HBs level. This study followed 3 435 653 donors for HBV DNA conversion over 4 years and 9 months. Infection phase was determined based on marker changes over DNA conversion. This study identified 115 hepatitis B surface antigen (HBsAg) conversions, 72 DNA-only conversions, and 15 DNA plus anti-hepatitis B core (anti-HBc) conversions among donors all negative for HBV DNA, HBsAg, and anti-HBc. Total incidence was 2.38/100 000 person-years (PY). None of these 202 new HBV infections arose in the group with anti-HBs titer ≥ 10 mIU/mL. In total, 30 anti-HBc-negative OBIs were identified (incidence; 0.35/100 000 PY); 7 showed typical secondary anti-HBs response, and 23 showed stable anti-HBc and anti-HBs levels at DNA conversion. The HBV infection-protective ability of anti-HBs ≥ 10 mIU/mL was reinforced. In addition to new infections, the blood donor population includes anti-HBc-positive- and negative OBI with immune reactions or abortive HBV infection.


Assuntos
Doadores de Sangue , DNA Viral , Anticorpos Anti-Hepatite B , Antígenos do Núcleo do Vírus da Hepatite B , Antígenos de Superfície da Hepatite B , Hepatite B , Humanos , Doadores de Sangue/estatística & dados numéricos , Incidência , Hepatite B/epidemiologia , Hepatite B/sangue , Hepatite B/imunologia , Antígenos de Superfície da Hepatite B/sangue , Masculino , Anticorpos Anti-Hepatite B/sangue , Feminino , Adulto , DNA Viral/sangue , Japão/epidemiologia , Pessoa de Meia-Idade , Antígenos do Núcleo do Vírus da Hepatite B/sangue , Antígenos do Núcleo do Vírus da Hepatite B/imunologia , Adulto Jovem , Vírus da Hepatite B/imunologia , Vírus da Hepatite B/genética , População do Leste Asiático
3.
BMC Infect Dis ; 24(1): 318, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38491438

RESUMO

INTRODUCTION: Childhood vaccination against hepatitis B has been recommended in Germany since 1995. WHO defines a primary vaccination series as successful if the initial hepatitis B surface antibody (anti-HBs) level is ≥ 10 IU/L directly after vaccination. Anti-HBs levels vary depending on the number of doses, type of vaccine, and time interval between the last two doses. In 2021, Germany began to recommend three instead of four doses of polyvalent hepatitis-B-containing vaccines. Our aim was to estimate the proportion of vaccinated children in Germany with anti-HBs levels < 10 IU/L, 10-99 IU/L, and ≥ 100 IU/L by number and type of vaccine, and assess if number of doses and compliance with recommended time interval between the last two doses are associated with an anti-HBs level ≥ 10 IU/L when considering type of vaccine and time since last dose. METHODS: We used data from a national cross-sectional study (2014-2017) of children (3-17 years). We excluded participants with unknown vaccination dates, unreadable or incomplete vaccination cards, and hepatitis B virus (HBV)-positive participants. We defined a recommended schedule as a vaccination series with at least six months between the two last doses and having three doses or more. We calculated weighted anti-HBs sero-prevalence for three anti-HBs levels: < 10 IU/L, 10-99 IU/L and ≥ 100 IU/L. We fitted two logistic regression models to examine the relationship between number of doses and recommended schedule on anti-HBs levels (≥ 10 IU/L and ≥ 100 IU/L) considering time since last dose and type of vaccine (Infanrix, Hexavac, Monovalent). RESULTS: We included 2,489 participants. The weighted proportion of vaccinated children per anti-HBs level was < 10 IU/L: 36.3% [95%CI 34.0-38.7%], 10-99 IU/L: 35.7% [33.2-38.2%] and ≥ 100 IU/L: 28.0% [25.9-30.2%]. We did not find an association between a recommended schedule of three versus four doses and anti-HBs ≥ 10 IU/L or ≥ 100 IU/L. CONCLUSIONS: Anti-HBs levels in later childhood were about equal, whether children received three or four doses. This implies that the change in the recommendations does not affect the anti-HBs level among children in Germany. Future studies are needed on the association of anti-HBs levels and adequate sustained protection against HBV.


Assuntos
Antígenos de Superfície da Hepatite B , Hepatite B , Criança , Humanos , Adolescente , Prevalência , Estudos Transversais , Vacinas contra Hepatite B , Anticorpos Anti-Hepatite B , Hepatite B/epidemiologia , Hepatite B/prevenção & controle , Vacinação/métodos , Vacinas Combinadas , Alemanha/epidemiologia
4.
Clin Chem Lab Med ; 62(6): 1149-1157, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38353144

RESUMO

OBJECTIVES: Newborn screening (NBS) for sickle cell disease (SCD) requires a robust, high-throughput method to detect hemoglobin S (HbS). Screening for SCD is performed by qualitative methods, such as isoelectric focusing (IEF), and both qualitative and quantitative methods such as high performance liquid chromatography (HPLC), capillary electrophoresis (CE), and tandem mass spectrometry (MS/MS). All these methods detect HbS, as well as low-level or absent HbA, and also other variants of hemoglobin. HPLC is considered as a reference method for NBS, because of its high sensitivity and specificity in detecting HbS. NeoSickle®, a fully automated matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) platform, combined with automated sample processing, a laboratory information management system and NeoSickle® software for automatic data interpretation, has increased the throughput of SCD testing. The purpose of this study was to compare the performances of NeoSickle® and HPLC. METHODS: A prospective study was conducted including 9,571 samples from the NBS program to compare MALDI-MS using NeoSickle® with an HPLC method. Correlation between the two methods was studied. For the MALDI-MS method, sensitivity, specificity, NPV, and PPV were calculated. RESULTS: We found over 99.4 % correlation between the HPLC and MALDI-MS results. NeoSickle® showed 100 % of sensitivity and specificity in detecting SCD syndrome, leading to positive and negative predictive values of 100 %. CONCLUSIONS: NeoSickle® is adapted to NBS for SCD, and can be used in first-line high-throughput screening to detect HbS, and beta-thalassemia major warning. When HbS is detected, second-line use of another specific method as HPLC is necessary.


Assuntos
Anemia Falciforme , Triagem Neonatal , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Humanos , Anemia Falciforme/diagnóstico , Anemia Falciforme/sangue , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Recém-Nascido , Estudos Prospectivos , Triagem Neonatal/métodos , Hemoglobina Falciforme/análise
5.
Biomed Chromatogr ; 38(3): e5799, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38041149

RESUMO

The management of life-threatening complications in patients with sickle cell disease (SCD) requires an accurate and reproducible quantification of haemoglobin A (HbA) and S (HbS) with a short turnaround time and 24-7 availability. We propose a novel method for quantifying HbA and HbS using the glycated haemoglobin (HbA1c) assay on a Tosoh HLC-723G8 (G8) analyser in variant mode. HbA and HbS results obtained using our method highly correlated with results obtained using a reference method (r > 0.99 for 124 samples of patients with SCD or sickle cell trait). Our method met laboratory requirements for linearity (coefficient of variation [CV] and bias <5%), between-run and within-run reproducibility (CV <10%) and carryover (<0.5%) over the range of HbS and HbA values expected in a therapeutic context. Using the G8 analyser in variant mode is viable for monitoring HbA and HbS concentrations in dire situations. This method is easy to use, quick (1.6 min per sample), and automatable and produces highly reproducible results without significant bias. Finally, it does not require modifications to the analytical pipeline recommended by the supplier, enabling a 24-7 availability without disrupting routine monitoring of HbA1c in the laboratory.


Assuntos
Anemia Falciforme , Hemoglobina A , Hemoglobina Falciforme , Humanos , Hemoglobinas Glicadas , Reprodutibilidade dos Testes
6.
Medicina (Kaunas) ; 60(3)2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38541162

RESUMO

Background and Objectives: Hepatitis B (HB) is a major global health problem and a potentially life-threatening disease caused by the hepatitis B virus (HBV). Also, it is an important cause of morbidity and mortality worldwide. Thanks to serological surveys, testing hepatitis B surface antibodies (anti-HBs) allows for serological assessments of their prevalence. The presence of anti-HBs, which protects against HBV infection, can be attributed to HB vaccination or natural HBV infection. The aim of our study was to evaluate the prevalence of HB surface antibodies (anti-HBs) as an indicator of collective immunity against HBV in the general population of the Autonomous Province of Vojvodina, Serbia. In addition, to distinguish whether anti-HBs were induced by the vaccine or by infection, the presence of antibodies against the hepatitis B core antigen (anti-HBc) was tested among those who were anti-HBs-positive. Materials and Methods: A total of 3467 residual sera samples, collected according to the specifications of the European Sero-Epidemiology Network 2 (ESEN2) study, from April 2015 to March 2016, were screened for the presence of anti-HBs using a chemiluminescence immunoassay. The difference between categorical variables was tested using the chi-square test. Results: Overall, 1870 (53.9%, 95% CI: 52.3-55.6) participants tested positive for anti-HBs. The median age of the study participants was 17 years (IQR 9-35). The anti-HB seroprevalence decreased with age, ranging from 80.7% (95% CI: 78.9-82.4) in the 1-19-year-old group to 16.4% (95% CI: 12.0-20.9) in the ≥60 years' age group. A total of 71 (3.8%, 95% CI: 2.9-4.7) serum samples were also anti-HBc-positive. Higher prevalence, but not statistically significant, was noticed in women (4.1%, 95% CI: 2.8-5.4) compared with men (3.5, 95% CI: 2.4-4.8) (p = 0.542). Also, there was a significant difference across the age groups, where those ≥60 years old had a prevalence of 65.9% (95% CI: 51.9-79.9) and the age category of 1-19-year-olds had just 0.2% (95% CI: 0.0-0.4) (p < 0.001). Conclusions: This study provides a comprehensive assessment of the anti-HBs seroprevalence of the general population in Vojvodina and provides an opportunity to better shape the national preventive strategy related to HBV.


Assuntos
Antígenos de Superfície da Hepatite B , Hepatite B , Masculino , Humanos , Feminino , Criança , Adolescente , Adulto Jovem , Adulto , Lactente , Pré-Escolar , Pessoa de Meia-Idade , Sérvia/epidemiologia , Iugoslávia , Estudos Soroepidemiológicos , Anticorpos Anti-Hepatite B , Hepatite B/epidemiologia , Hepatite B/prevenção & controle
7.
J Hepatol ; 79(5): 1129-1138, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37459920

RESUMO

BACKGROUND & AIMS: Chronic hepatitis B is a global public health problem, and coinfection with hepatitis delta virus (HDV) worsens disease outcome. Here, we describe a hepatitis B virus (HBV) surface antigen (HBsAg)-targeting monoclonal antibody (mAb) with the potential to treat chronic hepatitis B and chronic hepatitis D. METHODS: HBsAg-specific mAbs were isolated from memory B cells of HBV vaccinated individuals. In vitro neutralization was determined against HBV and HDV enveloped with HBsAg representing eight HBV genotypes. Human liver-chimeric mice were treated twice weekly with a candidate mAb starting 3 weeks post HBV inoculation (spreading phase) or during stable HBV or HBV/HDV coinfection (chronic phase). RESULTS: From a panel of human anti-HBs mAbs, VIR-3434 was selected and engineered for pre-clinical development. VIR-3434 targets a conserved, conformational epitope within the antigenic loop of HBsAg and neutralized HBV and HDV infection with higher potency than hepatitis B immunoglobulins in vitro. Neutralization was pan-genotypic against strains representative of HBV genotypes A-H. In the spreading phase of HBV infection in human liver-chimeric mice, a parental mAb of VIR-3434 (HBC34) prevented HBV dissemination and the increase in intrahepatic HBV RNA and covalently closed circular DNA. In the chronic phase of HBV infection or co-infection with HDV, HBC34 treatment decreased circulating HBsAg by >1 log and HDV RNA by >2 logs. CONCLUSIONS: The potently neutralizing anti-HBs mAb VIR-3434 reduces circulating HBsAg and HBV/HDV viremia in human liver-chimeric mice. VIR-3434 is currently in clinical development for treatment of patients with chronic hepatitis B or D. IMPACT AND IMPLICATIONS: Chronic infection with hepatitis B virus and co-infection with hepatitis D virus place approximately 290 million individuals worldwide at risk of severe liver disease and cancer. Available treatments result in low rates of functional cure or require lifelong therapy that does not eliminate the risk of liver disease. We isolated and characterized a potent human antibody that neutralizes hepatitis B and D viruses and reduces infection in a mouse model. This antibody could provide a new treatment for patients with chronic hepatitis B and D.

8.
Br J Haematol ; 203(4): 571-580, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37803485

RESUMO

This study aimed to investigate a stratified approach based on hepatitis B virus (HBV) surface antibody (anti-HBs) for managing HBV reactivation (HBVr) in lymphoma patients with serological protection against HBV. A retrospective analysis was conducted on 209 lymphoma patients with a baseline anti-HBs titre of ≥10 iu/L, who were either positive or negative for HBV core antibody (anti-HBc). The results revealed that 15.7% of patients lost serological protection following 6-month anti-lymphoma therapy. With a median follow-up of 28.1 months, the cumulative rates of HBVr at 6 months, 2 years and 4 years were 2.9%, 4.7% and 6.3% respectively. Without intervention, the overall rate of reactivation was 2.0% for patients with isolated anti-HBs and 10.5% for those with positive anti-HBs and anti-HBc. To identify patients at high risk of losing seroprotection and susceptible to HBVr, a predictive model was developed. The high-risk group had significantly higher rates of serological protection loss (27.8% vs. 2.2%) and cumulative incidence of HBVr (22.0% vs. 0%) compared to the low-risk group. Overall, this study highlights the risk of HBVr in lymphoma patients with positive anti-HBs, with or without positive anti-HBc, and recommends periodic monitoring for low-risk patients and early intervention for high-risk patients.


Assuntos
Hepatite B , Linfoma , Humanos , Vírus da Hepatite B/fisiologia , Rituximab/uso terapêutico , Estudos Retrospectivos , Antígenos de Superfície da Hepatite B , Anticorpos Anti-Hepatite B , Linfoma/tratamento farmacológico , Linfoma/induzido quimicamente , Hepatite B/prevenção & controle , Ativação Viral
9.
Transfusion ; 63(6): 1250-1254, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37129363

RESUMO

BACKGROUND: Hepatitis B virus (HBV)-positive individuals with isolated anti-HBs are found among HBV vaccine recipients and healthy blood donors with no vaccination history. HBV infectivity from blood transfusions derived from such individuals remains unclear. CASE PRESENTATION: A male patient who received transfusion with blood negative for individual donation-NAT, HBsAg and anti-HBc but weakly positive for anti-HBs developed typical transfusion-transmitted (TT)-HBV with anti-HBc response. The responsible blood donor was a frequent repeat donor showing a marked increase in anti-HBs titer without anti-HBc response 84 days after index donation. Test results for his past donations showed transient viremia with very low viral load and fluctuating low-level anti-HBs. The HBV vaccination history of this donor was unknown. DISCUSSION: Anti-HBs and anti-HBc kinetics of the donor suggest a second antibody response to new HBV challenge, representing a vaccine breakthrough case. On the other hand, transient low-level viremia and fluctuating anti-HBs in the test results of past donations suggested chronic occult HBV infection with isolated anti-HBs. CONCLUSION: Whatever the basic infection state, blood donors with isolated weak anti-HBs may include a small population with a risk of causing TT-HBV. Identifying individuals harboring such TT-HBV risk among individuals positive only for anti-HBs is difficult under current screening strategies. Active surveillance for the occurrence of TT-HBV with blood positive only for anti-HBs is necessary.


Assuntos
Hepatite B Crônica , Hepatite B , Humanos , Masculino , Vírus da Hepatite B/genética , Viremia , Anticorpos Anti-Hepatite B , Antígenos de Superfície da Hepatite B , Antígenos do Núcleo do Vírus da Hepatite B , Vacinas contra Hepatite B , Doadores de Sangue , DNA Viral
10.
Transfusion ; 63(3): 507-514, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36519666

RESUMO

BACKGROUND: Sickle cell trait (SCT) testing of red blood cell (RBC) units is sometimes performed to identify and divert units containing hemoglobin S (HbS). Recipients strategically guarded against this exposure include fetuses, neonates, and children with sickle cell disease (SCD). The clinical necessity of this practice is unclear. STUDY DESIGN AND METHODS: A one-year audit (2018) was performed at a pediatric tertiary care hospital that tests for SCT in RBC units prescribed to children with SCD and neonates. The impact of incorporating varying numbers of SCT RBC units in a single-unit top-up, partial-manual red cell exchange, and automated erythrocytapheresis was modeled in four typical-parameter age scenarios (2, 5, 10, and 18 years) sharing a high baseline HbS. Additionally, a survey assessing SCT testing practices was administered to Canadian pediatric hospital transfusion laboratories serving hemoglobinopathy programs. RESULTS: Of 2268 donor RBC units tested, one was positive for SCT (0.04% [95% CI: 0.01%-0.24%]), at a cost of $19,384.56 CAD. The impact of SCT unit incorporation on lost HbS reduction was modest (Δ1%-3% [automated erythrocytapheresis] and Δ4%-15% [top-up/partial manual exchange]). The survey (with all 13 sites responding) showed variable SCT testing practice; four (31%) do not test, four (31%) test for children with SCD, and six (46%) test for neonates. CONCLUSION: RBC SCT testing may be more costly than beneficial or necessary in children with SCD. As of 2019, our transfusion service has ceased SCT testing for this population. Further research in the fetal/neonatal populations is needed to overturn this entrenched practice.


Assuntos
Anemia Falciforme , Traço Falciforme , Recém-Nascido , Criança , Humanos , Traço Falciforme/diagnóstico , Transfusão de Eritrócitos , Canadá , Anemia Falciforme/diagnóstico , Anemia Falciforme/terapia , Eritrócitos/metabolismo , Hemoglobina Falciforme/metabolismo
11.
Liver Int ; 43(6): 1213-1224, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37029645

RESUMO

BACKGROUNDS AND AIMS: Toll-like receptor (TLR) agonists have been developed as adjuvants to efficiently induce antiviral immune responses. Specificity and potency of these compounds are essential requirements for clinical trial applications. In patients with hepatitis B virus (HBV) infections, sustained loss of hepatitis B surface antigen (HBsAg) is a therapeutic goal, which may be achievable by the sequential activation of follicular helper T cells (Tfh) and antibody-secreting B cells. We aimed to elucidate whether novel TLR7 agonist, GS-986, could activate immune responses involved in HBV elimination. METHODS: To clarify the impact of GS-986 on pDCs, we quantified the expression levels of surface markers and evaluated for Tfh induction in a culture model consisting of human pDCs with allogeneic naïve CD4+ T cells. In addition, we examined whether GS-986 could enhance HBs antibody production capacity using PBMC from CHB patients. RESULTS: pDCs from CHB patients had lower OX40L expression and as well as impaired capacity for Tfh induction compared with those from healthy donors. However, GS-986-stimulated pDCs from CHB patients expressed OX40L and produced IL-6 and IL-12, resulting in the induction of IL-21-producing Tfh cells (CXCR5+ PD-1+ CD4+ ) from naïve CD4+ T cells. The Tfh-inducing capacity of GS-986 was reduced in the presence of an anti-OX40L blocking antibody. Furthermore, GS-986 promoted HBsAg-specific antibody production in PBMCs from CHB patients. CONCLUSIONS: GS-986 is an adjuvant that stimulates pDCs to induce Tfh differentiation and antigen-specific B-cell production. This immune profile may be beneficial for therapeutic application as an immune modulator in CHB patients.


Assuntos
Antivirais , Hepatite B Crônica , Receptor 7 Toll-Like , Hepatite B Crônica/tratamento farmacológico , Humanos , Receptor 7 Toll-Like/agonistas , Antivirais/uso terapêutico , Masculino , Feminino , Pessoa de Meia-Idade , Regulação para Cima , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD4-Positivos/efeitos dos fármacos , Diferenciação Celular , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/metabolismo , Células T Auxiliares Foliculares/citologia , Células T Auxiliares Foliculares/efeitos dos fármacos , Antígenos de Superfície da Hepatite B/metabolismo , Anticorpos Antivirais/metabolismo
12.
Dig Dis Sci ; 68(12): 4511-4520, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37891440

RESUMO

BACKGROUND AND AIMS: We and others have previously described that hepatitis B surface antibody (anti-HBs) seems to protect against clinically significant HBV reactivation in cohort studies of patients undergoing anti-tumor necrosis factor (TNF) therapy. However, there were too few cases of HBV reactivation within cohort studies to assess the role of anti-HBs titer on reactivation. The purpose of this study was to systematically review the correlation between anti-HBs titer and the degree of clinically relevant HBV reactivation in patients undergoing anti-TNF therapy. METHODS AND RESULTS: We systemically reviewed all studies discussing anti-TNF therapy in patients with resolved HBV infection, defined as hepatitis surface antigen (HBsAg) negative and hepatitis B core antibody (anti-HBc) positive. We identified a total of 48 cases of reactivation from 5 cohort studies and 10 case reports or case series; 21 were anti-HBs negative, 7 were only reported as anti-HBs positive, 16 were anti-HBs positive with titer below 100, and 4 were anti-HBs positive with titer above 100. HBsAg sero-reversion was dominantly seen in patients with negative, low and/or declining anti-HBs titers. There was a significant trend toward less clinically relevant form of reactivation with increase in baseline anti-HBs titer (p = 0.022). CONCLUSION: Anti-HBs titers greater than 100 iU/L protect against clinically relevant HBV reactivation, while patients with low anti-HBs titers or negative anti-HBs had more clinically relevant HBV reactivation and higher rates of HBsAg sero-reversion. This suggests the importance of baseline quantitative anti-HBs prior to starting anti-TNF therapy and consideration vaccination for boosting anti-HBs titers prior to and/or during therapy.


Assuntos
Vírus da Hepatite B , Hepatite B , Humanos , Antígenos de Superfície da Hepatite B , Inibidores do Fator de Necrose Tumoral/farmacologia , Anticorpos Anti-Hepatite B , Hepatite B/diagnóstico , Hepatite B/tratamento farmacológico , Ativação Viral
13.
J Clin Apher ; 38(5): 529-539, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37198953

RESUMO

BACKGROUND: Patients with sickle cell disease (SCD) frequently undergo prophylactic red blood cell (RBC) exchange transfusion and simple transfusion (RCE/T) to prevent complications of disease, such as stroke. These treatment procedures are performed with a target hemoglobin S (HbS) of ≤30%, or a goal of maintaining an HbS level of <30% immediately prior to the next transfusion. However, there is a lack of evidence-based instructions for how to perform RCE/T in a way that will result in an HbS value <30% between treatments. PRINCIPAL OBJECTIVE: To determine whether targets for post-treatment HbS (post-HbS) or post-treatment HCT (post-HCT) can help to maintain an HbS <30% or <40% between treatments. MATERIALS AND METHODS: We performed a retrospective study of patients with SCD treated with RCE/T at Montefiore Medical Center from June 2014 to June 2016. The analysis included patients of all ages, and data including 3 documented parameters for each RCE/T event: post-HbS, post-HCT, and follow-up HbS (F/u-HbS), which is the pre-treatment HbS prior to the next RCE/T. Generalized linear mixed model was used for estimating the association between post-HbS or post-HCT levels and F/u-HbS <30%. RESULTS: Based on our results, targeting post-HbS ≤10% was associated with higher odds of having events of F/u-HbS <30% between monthly treatments. Targeting post-HbS ≤15% was associated with higher odds of events of F/u-HbS < 40%. As compared to post-HCT ≤30%, a post-HCT >30%-36% did not contribute to more F/u-HbS <30% or HbS <40% events. CONCLUSIONS: For patients with SCD undergoing regular RCE/T for stroke prevention, a post-HbS ≤10% can be used as a goal to help maintain an HbS <30% for 1 month, and a post-HbS ≤15% allowed patients to maintain HbS <40%.

14.
J Bacteriol ; 204(8): e0015122, 2022 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-35862733

RESUMO

The prokaryotic nucleoid-associated protein (NAP) HU is both highly conserved and ubiquitous. Deletion of HU causes pleiotropic phenotypes, making it difficult to uncover the critical functions of HU within a bacterial cell. In their recent work, Karaboja and Wang (J Bacteriol 204:e00119-22, 2022, https://doi.org/10.1128/JB.00119-22) show that one essential function of Bacillus subtilis HU (HBsu) is to drive the DnaA-dependent initiation of DNA replication at the chromosome origin. We discuss the possible roles of HBsu in replication initiation and other essential cellular functions.


Assuntos
Bacillus subtilis , Proteínas de Ligação a DNA , Bacillus subtilis/genética , Bacillus subtilis/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Replicação do DNA , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo
15.
J Viral Hepat ; 29(11): 958-967, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35876456

RESUMO

Absence of anti-HBc reactivity with detectable anti-HBs was observed in blood donors with occult hepatitis B virus (HBV) infection (OBI). The prevalence and mechanisms underlying this uncommon condition were investigated over time in Chinese blood donors with OBI. Isolated anti-HBs OBI status was identified from 466,911 donors from Dalian, China, and monitored in follow-up (range: 2.6-84.3 months). HBV vaccination status was documented, and infecting viral strains were characterized. Of 451 confirmed OBIs (1:1035), 43 (9.5%; 1:10,858) had isolated anti-HBs as only serological marker. Isolated anti-HBs OBIs differed from anti-HBc-reactive OBIs by significantly younger age (median 24 years), higher HBV DNA (median: 20 IU/ml) and anti-HBs (median 60.5 IU/L) levels, paucity of mutations in HBV Core and S proteins, and high vaccination rate (72%). Vaccinated isolated anti-HBs OBIs (n = 31) differed from unvaccinated (n = 11) by significantly younger age (22 vs 38 years), higher anti-HBs level at index (48% vs 9% with anti-HBs >100 IU/L) and higher frequency of anti-HBs immune response (44% vs 20%). Of 15 vaccinated and 5 unvaccinated OBIs follow-up, 65% (8 vaccinated and 5 unvaccinated) became HBV DNA negative suggesting aborted recent infection, while 35% (7 vaccinated) had low persistent viraemia 2 to 65 months post index. In conclusion, isolated anti-HBs OBI in Chinese blood donors appears associated with young, vaccinated, adults exposed to HBV who predominantly develop low level aborted infection revealed by transient HBV DNA and immune anti-HBs response. However, a subset of individuals still experienced low but persistent viral replication whose clinical outcome remains uncertain.


Assuntos
Hepatite B Crônica , Hepatite B , Adulto , Doadores de Sangue , DNA Viral , Genótipo , Hepatite B/epidemiologia , Hepatite B/prevenção & controle , Anticorpos Anti-Hepatite B , Antígenos do Núcleo do Vírus da Hepatite B , Antígenos de Superfície da Hepatite B , Vírus da Hepatite B , Humanos , Adulto Jovem
16.
BMC Infect Dis ; 22(1): 159, 2022 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-35180842

RESUMO

BACKGROUND: The short-term 0-1-2-month hepatitis B virus (HBV) vaccination schedule was previously implemented in the adult population; however, its long-term immune effect remains unclear. The present study aimed to investigate (1) the 2-month and 2-year immune effects of HBV vaccination and (2) the compliance rate between the 0-1-2-month and 0-1-6-month vaccination schedules in adults. METHOD: A total of 1281 subjects tested for hepatitis B surface antigen HBsAg(-) and hepatitis B surface antibody (anti-HBs)(-) were recruited. Participants from two distant counties were inoculated with the hepatitis B yeast vaccine at 10 µg per dose, with vaccination schedules of 0, 1, and 2 months (n = 606) and 0, 1, and 6 months (n = 675); sequential follow-up was performed at 2 months and 2 years after the 3rd injection. RESULTS: There were no significant differences in the anti-HBs seroconversion rates between the those in the 0-1-2-month and 0-1-6-month vaccination schedule groups at 2 months (91.96% vs. 89.42%, p = 0.229) and 2 years (81.06% vs. 77.14%, p = 0.217). The quantitative anti-HBs level in those in the 0-1-2-month vaccination schedule group was not different from that in those in the 0-1-6-month vaccination schedule group at 2 months (anti-HBs1) (342.12 ± 378.42 mIU/ml vs. 392.38 ± 391.96 mIU/ml, p = 0.062), but it was higher at 2 years (anti-HBs2) (198.37 ± 286.44 mIU/ml vs. 155.65 ± 271.73 mIU/ml, p = 0.048). According to the subgroup analysis, the 0-1-2-month vaccination schedule induced better maintenance (p = 0.041) and longer reinforcement (p = 0.019) than the 0-1-6 vaccination schedule. The 0-1-2-month vaccination schedule group also had a higher 3rd injection completion rate (89.49% vs. 84.49%, p = 0.010). CONCLUSION: The 0-1-2-month vaccination schedule was associated with a similar short-term immune effect and might induce better long-term immune memory and a higher completion rate in the adult population. Trial registration None.


Assuntos
Vírus da Hepatite B , Hepatite B , Adulto , Hepatite B/prevenção & controle , Anticorpos Anti-Hepatite B , Antígenos de Superfície da Hepatite B , Vacinas contra Hepatite B , Humanos , Imunização Secundária , Vacinação
17.
Clin Chem Lab Med ; 60(6): 886-890, 2022 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-35218178

RESUMO

OBJECTIVES: The observation of numerous new structural defects in hemoglobin (Hb) has often been linked to the evolution and development of device technologies used for the separation and quantification of hemoglobin components. However, the increased use of preventive tests for hemoglobinopathies and separative methods to quantify glycated hemoglobin (HbA1c) also contributed to these observations, as demonstrated by the case described here. Our aim is to emphasize that different separative method can provide more useful information in patient management. METHODS: A 64-year-old diabetic woman of Moroccan descent was examined in the context of HbA1c monitoring. The test was performed using high performance liquid chromatography (HPLC) and capillary electrophoresis (CE) systems. Molecular characterization was performed by direct sequencing of the ß and α globin genes. RESULTS: The two methods used showed the presence of an anomalous fraction identified as HbS, already observed previously, but only through CE it was possible to observe the presence of another variant and its hybrid components. Direct sequencing of ß and α globin genes confirmed heterozygous HbS [ß6 (A3) Glu→Val; HBB: c.20A>T] and allowed to identify a mutation on the α2, [α114 (GH2) Pro→Leu gene; HBA2: c.344C>T] corresponding to the rare Hb Nouakchott variant. CONCLUSIONS: The two Hb variants highlighted by the EC and the molecular characterization therefore allowed adequate advice, the correct assessment of HbA1c and metabolic status and therefore better clinical management of the patient. The availability of different instruments in the same laboratory, confirming situations of diagnostic uncertainty, represents a valuable opportunity that should be encouraged.


Assuntos
Hemoglobinopatias , Hemoglobinas Anormais , Cromatografia Líquida de Alta Pressão , Eletroforese Capilar/métodos , Feminino , Hemoglobinas Glicadas/análise , Hemoglobinas Glicadas/genética , Hemoglobinopatias/diagnóstico , Hemoglobinopatias/genética , Hemoglobinas Anormais/análise , Humanos , Pessoa de Meia-Idade , Mutação , alfa-Globinas/genética
18.
New Microbiol ; 45(4)2022 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-36066216

RESUMO

Viral hepatitis still represents a significant worldwide public health issue, being an important cause of morbidity and mortality. The aim of our study is to evaluate the prevalence of Hepatitis B virus (HBV) markers from serologic analysis of hospitalized patients at University Hospital of Campania "Luigi Vanvitelli" and also to investigate the prevalence of HBV/HCV coinfection. We screened serum Anti-Hepatitis B surface antigen (HBsAg), antibody to HBsAg (anti-HBs), antibody to hepatitis B core antigen (anti-HBc), and antibody to Hepatitis C Virus (Anti-HCV) Anti-HCV from January to December 2020. Analyses of HBV serological profile based on age showed that the 51-60 age group was the most numerous and with the highest cases of HBsAg. The 61-70 age group recorded the highest prevalence of anti-HBc while age groups 0-10 years and 31-40 years the highest cases of anti-HBs. Antibody levels decline with time. In subjects older than 20 years, compared to vaccinated cohort individuals, anti-HBc seropositive prevalence increased linearly. This study underlined, in our geographic region, the decreased incidence of hepatitis B and high immunogenicity in the young population. Therefore, administration of HBV vaccine booster dose should be considered for the population rather than vaccination in the first year of life. In conclusion, our findings reaffirm the importance of health surveillance in hospitalized subjects, stressing the need to improve immunized subjects to increase the general population's health.

19.
Molecules ; 27(3)2022 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-35164270

RESUMO

Fluorine is a common substituent in medicinal chemistry and is found in up to 50% of the most profitable drugs. In this study, a statistical analysis of the nature, geometry, and frequency of hydrogen bonds (HBs) formed between the aromatic and aliphatic C-F groups of small molecules and biological targets found in the Protein Data Bank (PDB) repository was presented. Interaction energies were calculated for those complexes using three different approaches. The obtained results indicated that the interaction energy of F-containing HBs is determined by the donor-acceptor distance and not by the angles. Moreover, no significant relationship between the energies of HBs with fluorine and the donor type was found, implying that fluorine is a weak HB acceptor for all types of HB donors. However, the statistical analysis of the PDB repository revealed that the most populated geometric parameters of HBs did not match the calculated energetic optima. In a nutshell, HBs containing fluorine are forced to form due to the stronger ligand-receptor neighboring interactions, which make fluorine the "donor's last resort".


Assuntos
Flúor/química , Hidrogênio/química , Proteínas/química , Animais , Bases de Dados de Proteínas , Humanos , Ligação de Hidrogênio , Ligantes , Modelos Moleculares
20.
Med J Armed Forces India ; 78(2): 198-203, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35463555

RESUMO

Background: Hepatitis B (HepB) is an important vaccine preventable infection among healthcare workers (HCWs). Vaccination against Hep B virus, remains the foremost preventive approach. This study aims to measure the antibody titres to Hep B surface antigen (anti-HBs) in a mixed cohort of HCWs. It also aims to study the association between time since vaccination and the anti-HBs titres thus evaluating the duration of seroprotection. Methods: A total of 200 HCWs, including nursing students (n = 112), nursing staff (n = 49), laboratory technicians (n = 30) and doctors (n = 9) who had received all three doses of the Hep B vaccine and met the inclusion criteria of having taken all three doses of vaccine were included in this study. Anti-HBs titres were estimated by bioMérieux mini VIDAS® automated immunoassay based on the principle of enzyme-linked fluorescence assay. Results: Two hundred subjects aged 19 to 52 years were included in the study; mean age was 27.29 ± 0.568 years. Duration since vaccination in the study cohort was ≤ 5 years in 149 (74.5.0%), 6-10 years in 20 (10.0%) and >10 years in 31 (15.5%) subjects. Postvaccination antibody titres were > 100 mIU/ml in 85.0%, 10-100 mIU/ml in 11.0% and ≤ 10 mIU/ml in 3.5%. There was a decline noted in antibody titres as duration after vaccination increased. Increasing age was associated with falling protective titres. Conclusion: The study revealed that majority of the HCWs had adequate anti-HBs titres and were protected after vaccination.

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