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1.
J Immunother Cancer ; 12(8)2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39107131

RESUMO

BACKGROUND: Checkpoint inhibitor therapy has demonstrated overall survival benefit in multiple tumor types. Tumor mutational burden (TMB) is a predictive biomarker for response to immunotherapies. This study evaluated the efficacy of nivolumab+ipilimumab in multiple tumor types based on TMB status evaluated using either tumor tissue (tTMB) or circulating tumor DNA in the blood (bTMB). PATIENTS AND METHODS: Patients with metastatic or unresectable solid tumors with high (≥10 mutations per megabase) tTMB (tTMB-H) and/or bTMB (bTMB-H) who were refractory to standard therapies were randomized 2:1 to receive nivolumab+ipilimumab or nivolumab monotherapy in an open-label, phase 2 study (CheckMate 848; NCT03668119). tTMB and bTMB were determined by the Foundation Medicine FoundationOne® CDx test and bTMB Clinical Trial Assay, respectively. The dual primary endpoints were objective response rate (ORR) in patients with tTMB-H and/or bTMB-H tumors treated with nivolumab+ipilimumab. RESULTS: In total, 201 patients refractory to standard therapies were randomized: 135 had tTMB-H and 125 had bTMB-H; 82 patients had dual tTMB-H/bTMB-H. In patients with tTMB-H, ORR was 38.6% (95% CI 28.4% to 49.6%) with nivolumab+ipilimumab and 29.8% (95% CI 17.3% to 44.9%) with nivolumab monotherapy. In patients with bTMB-H, ORR was 22.5% (95% CI 13.9% to 33.2%) with nivolumab+ipilimumab and 15.6% (95% CI 6.5% to 29.5%) with nivolumab monotherapy. Early and durable responses to treatment with nivolumab+ipilimumab were seen in patients with tTMB-H or bTMB-H. The safety profile of nivolumab+ipilimumab was manageable, with no new safety signals. CONCLUSIONS: Patients with metastatic or unresectable solid tumors with TMB-H, as determined by tissue biopsy or by blood sample when tissue biopsy is unavailable, who have no other treatment options, may benefit from nivolumab+ipilimumab. TRIAL REGISTRATION NUMBER: NCT03668119.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica , Ipilimumab , Neoplasias , Nivolumabe , Humanos , Nivolumabe/uso terapêutico , Nivolumabe/administração & dosagem , Nivolumabe/farmacologia , Feminino , Ipilimumab/uso terapêutico , Ipilimumab/administração & dosagem , Ipilimumab/farmacologia , Masculino , Neoplasias/tratamento farmacológico , Neoplasias/genética , Pessoa de Meia-Idade , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Adulto , Mutação , Idoso de 80 Anos ou mais , Metástase Neoplásica
2.
Clin Cancer Res ; 30(4): 803-813, 2024 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-38060202

RESUMO

PURPOSE: Programmed cell death protein 1 (PD-1) expression on CD8+TIM-3-LAG-3- tumor-infiltrating cells predicts positive response to PD-1 blockade in metastatic clear-cell renal cell carcinoma (mccRCC). Because inhibition of PD-1 signaling in regulatory T cells (Treg) augments their immunosuppressive function, we hypothesized that PD-1 expression on tumor-infiltrating Tregs would predict resistance to PD-1 inhibitors. EXPERIMENTAL DESIGN: PD-1+ Tregs were phenotyped using multiparametric immunofluorescence in ccRCC tissues from the CheckMate-025 trial (nivolumab: n = 91; everolimus: n = 90). Expression of CD8, PD-1, TIM-3, and LAG-3 was previously determined (Ficial and colleagues, 2021). Clinical endpoints included progression-free survival (PFS), overall survival (OS), and objective response rate (ORR). RESULTS: In the nivolumab (but not everolimus) arm, high percentage of PD-1+ Tregs was associated with shorter PFS (3.19 vs. 5.78 months; P = 0.021), shorter OS (18.1 vs. 27.7 months; P = 0.013) and marginally lower ORR (12.5% vs. 31.3%; P = 0.059). An integrated biomarker (PD-1 Treg/CD8 ratio) was developed by calculating the ratio between percentage of PD-1+Tregs (marker of resistance) and percentage of CD8+PD-1+TIM-3-LAG-3- cells (marker of response). In the nivolumab (but not everolimus) arm, patients with high PD-1 Treg/CD8 ratio experienced shorter PFS (3.48 vs. 9.23 months; P < 0.001), shorter OS (18.14 vs. 38.21 months; P < 0.001), and lower ORR (15.69% vs. 40.00%; P = 0.009). Compared with the individual biomarkers, the PD-1 Treg/CD8 ratio showed improved ability to predict outcomes to nivolumab versus everolimus. CONCLUSIONS: PD-1 expression on Tregs is associated with resistance to PD-1 blockade in mccRCC, suggesting that targeting Tregs may synergize with PD-1 inhibition. A model that integrates PD-1 expression on Tregs and CD8+TIM-3-LAG-3- cells has higher predictive value.


Assuntos
Carcinoma de Células Renais , Humanos , Carcinoma de Células Renais/patologia , Nivolumabe/uso terapêutico , Linfócitos T Reguladores/metabolismo , Receptor Celular 2 do Vírus da Hepatite A/metabolismo , Everolimo/uso terapêutico , Receptor de Morte Celular Programada 1/metabolismo
3.
Cureus ; 15(11): e48787, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38098914

RESUMO

Bevacizumab-induced nephropathy is a common adverse event observed in patients who receive chemotherapy. These patients usually present with hypertension and nephrotic range proteinuria. Thrombotic microangiopathy is the characteristic histologic pattern of bevacizumab-induced nephropathy. However, a few cases reported IgA vasculitis with nephritis as an unusual pattern. In this case report, we describe a patient diagnosed with bevacizumab-induced nephropathy with a distinctive histologic pattern demonstrating focal proliferative crescentic glomerulonephritis with polyclonal immune complex deposition.

4.
Front Immunol ; 13: 982746, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36605197

RESUMO

Background: Even during long-term combination antiretroviral therapy (cART), people living with HIV (PLHIV) have a dysregulated immune system, characterized by persistent immune activation, accelerated immune ageing and increased risk of non-AIDS comorbidities. A multi-omics approach is applied to a large cohort of PLHIV to understand pathways underlying these dysregulations in order to identify new biomarkers and novel genetically validated therapeutic drugs targets. Methods: The 2000HIV study is a prospective longitudinal cohort study of PLHIV on cART. In addition, untreated HIV spontaneous controllers were recruited. In-depth multi-omics characterization will be performed, including genomics, epigenomics, transcriptomics, proteomics, metabolomics and metagenomics, functional immunological assays and extensive immunophenotyping. Furthermore, the latent viral reservoir will be assessed through cell associated HIV-1 RNA and DNA, and full-length individual proviral sequencing on a subset. Clinical measurements include an ECG, carotid intima-media thickness and plaque measurement, hepatic steatosis and fibrosis measurement as well as psychological symptoms and recreational drug questionnaires. Additionally, considering the developing pandemic, COVID-19 history and vaccination was recorded. Participants return for a two-year follow-up visit. The 2000HIV study consists of a discovery and validation cohort collected at separate sites to immediately validate any finding in an independent cohort. Results: Overall, 1895 PLHIV from four sites were included for analysis, 1559 in the discovery and 336 in the validation cohort. The study population was representative of a Western European HIV population, including 288 (15.2%) cis-women, 463 (24.4%) non-whites, and 1360 (71.8%) MSM (Men who have Sex with Men). Extreme phenotypes included 114 spontaneous controllers, 81 rapid progressors and 162 immunological non-responders. According to the Framingham score 321 (16.9%) had a cardiovascular risk of >20% in the next 10 years. COVID-19 infection was documented in 234 (12.3%) participants and 474 (25.0%) individuals had received a COVID-19 vaccine. Conclusion: The 2000HIV study established a cohort of 1895 PLHIV that employs multi-omics to discover new biological pathways and biomarkers to unravel non-AIDS comorbidities, extreme phenotypes and the latent viral reservoir that impact the health of PLHIV. The ultimate goal is to contribute to a more personalized approach to the best standard of care and a potential cure for PLHIV.


Assuntos
COVID-19 , Infecções por HIV , Minorias Sexuais e de Gênero , Masculino , Humanos , Feminino , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Homossexualidade Masculina , Estudos Prospectivos , Vacinas contra COVID-19/uso terapêutico , Espessura Intima-Media Carotídea , Estudos Longitudinais , Multiômica
5.
Sensors (Basel) ; 18(10)2018 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-30274340

RESUMO

One of the most common symptoms observed among most of the Parkinson's disease patients that affects movement pattern and is also related to the risk of fall, is usually termed as "freezing of gait (FoG)". To allow systematic assessment of FoG, objective quantification of gait parameters and automatic detection of FoG are needed. This will help in personalizing the treatment. In this paper, the objectives of the study are (1) quantification of gait parameters in an objective manner by using the data collected from wearable accelerometers; (2) comparison of five estimated gait parameters from the proposed algorithm with their counterparts obtained from the 3D motion capture system in terms of mean error rate and Pearson's correlation coefficient (PCC); (3) automatic discrimination of FoG patients from no FoG patients using machine learning techniques. It was found that the five gait parameters have a high level of agreement with PCC ranging from 0.961 to 0.984. The mean error rate between the estimated gait parameters from accelerometer-based approach and 3D motion capture system was found to be less than 10%. The performances of the classifiers are compared on the basis of accuracy. The best result was accomplished with the SVM classifier with an accuracy of approximately 88%. The proposed approach shows enough evidence that makes it applicable in a real-life scenario where the wearable accelerometer-based system would be recommended to assess and monitor the FoG.


Assuntos
Acelerometria , Marcha/fisiologia , Aprendizado de Máquina , Doença de Parkinson/diagnóstico , Doença de Parkinson/fisiopatologia , Dispositivos Eletrônicos Vestíveis , Adulto , Idoso , Idoso de 80 Anos ou mais , Humanos , Pessoa de Meia-Idade
6.
Sci Transl Med ; 10(437)2018 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-29669853

RESUMO

The persistence of HIV reservoirs, including latently infected, resting CD4+ T cells, is the major obstacle to cure HIV infection. CD32a expression was recently reported to mark CD4+ T cells harboring a replication-competent HIV reservoir during antiretroviral therapy (ART) suppression. We aimed to determine whether CD32 expression marks HIV latently or transcriptionally active infected CD4+ T cells. Using peripheral blood and lymphoid tissue of ART-treated HIV+ or SIV+ subjects, we found that most of the circulating memory CD32+ CD4+ T cells expressed markers of activation, including CD69, HLA-DR, CD25, CD38, and Ki67, and bore a TH2 phenotype as defined by CXCR3, CCR4, and CCR6. CD32 expression did not selectively enrich for HIV- or SIV-infected CD4+ T cells in peripheral blood or lymphoid tissue; isolated CD32+ resting CD4+ T cells accounted for less than 3% of the total HIV DNA in CD4+ T cells. Cell-associated HIV DNA and RNA loads in CD4+ T cells positively correlated with the frequency of CD32+ CD69+ CD4+ T cells but not with CD32 expression on resting CD4+ T cells. Using RNA fluorescence in situ hybridization, CD32 coexpression with HIV RNA or p24 was detected after in vitro HIV infection (peripheral blood mononuclear cell and tissue) and in vivo within lymph node tissue from HIV-infected individuals. Together, these results indicate that CD32 is not a marker of resting CD4+ T cells or of enriched HIV DNA-positive cells after ART; rather, CD32 is predominately expressed on a subset of activated CD4+ T cells enriched for transcriptionally active HIV after long-term ART.


Assuntos
Infecções por HIV/metabolismo , Receptores de IgG/metabolismo , Antirretrovirais/uso terapêutico , Linfócitos T CD4-Positivos/metabolismo , Infecções por HIV/tratamento farmacológico , Humanos , Técnicas In Vitro , Linfócitos/metabolismo , Receptores CCR4/metabolismo , Receptores CCR6/metabolismo , Receptores CXCR3/metabolismo
7.
PLoS One ; 12(10): e0186244, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29023601

RESUMO

The emergence of H5, H7, and H9 avian influenza virus subtypes in humans reveals their pandemic potential. Although human-to-human transmission has been limited, the genetic reassortment of the avian and human/porcine influenza viruses or mutations in some of the genes resulting in virus replication in the upper respiratory tract of humans could generate novel pandemic influenza viruses. Current vaccines do not provide cross protection against antigenically distinct strains of the H5, H7, and H9 influenza viruses. Therefore, newer vaccine approaches are needed to overcome these potential threats. We developed an egg-independent, adenovirus vector-based, multi-epitope (ME) vaccine approach using the relatively conserved immunogenic domains of the H5N1 influenza virus [M2 ectodomain (M2e), hemagglutinin (HA) fusion domain (HFD), T-cell epitope of nucleoprotein (TNP). and HA α-helix domain (HαD)]. Our ME vaccine induced humoral and cell-mediated immune responses and caused a significant reduction in the viral loads in the lungs of vaccinated mice that were challenged with antigenically distinct H5, H7, or H9 avian influenza viruses. These results suggest that our ME vaccine approach provided broad protection against the avian influenza viruses. Further improvement of this vaccine will lead to a pre-pandemic vaccine that may lower morbidity, hinder transmission, and prevent mortality in a pandemic situation before a strain-matched vaccine becomes available.


Assuntos
Proteção Cruzada , Vírus da Influenza A/imunologia , Vacinas contra Influenza/uso terapêutico , Influenza Humana/prevenção & controle , Adenoviridae , Animais , Epitopos/imunologia , Epitopos de Linfócito T/química , Epitopos de Linfócito T/imunologia , Hemaglutininas Virais/química , Hemaglutininas Virais/imunologia , Humanos , Camundongos , Proteínas do Core Viral/química , Proteínas do Core Viral/imunologia , Carga Viral , Proteínas da Matriz Viral/química , Proteínas da Matriz Viral/imunologia
8.
Expert Rev Vaccines ; 16(11): 1141-1154, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28925296

RESUMO

INTRODUCTION: Annual vaccination is one of the most efficient and cost-effective strategies to prevent and control influenza epidemics. Most of the currently available influenza vaccines are strong inducers of antibody responses against viral surface proteins, hemagglutinin (HA) and neuraminidase (NA), but are poor inducers of cell-mediated immune responses against conserved internal proteins. Moreover, due to the high variability of viral surface proteins because of antigenic drift or antigenic shift, many of the currently licensed vaccines confer little or no protection against drift or shift variants. Areas covered: Next generation influenza vaccines that can induce humoral immune responses to receptor-binding epitopes as well as broadly neutralizing conserved epitopes, and cell-mediated immune responses against highly conserved internal proteins would be effective against variant viruses as well as a novel pandemic influenza until circulating strain-specific vaccines become available. Here we discuss vaccine approaches that have the potential to provide broad spectrum protection against influenza viruses. Expert commentary: Based on current progress in defining cross-protective influenza immunity, it seems that the development of a universal influenza vaccine is feasible. It would revolutionize the strategy for influenza pandemic preparedness, and significantly impact the shelf-life and protection efficacy of seasonal influenza vaccines.


Assuntos
Proteção Cruzada , Vacinas contra Influenza/imunologia , Vacinas contra Influenza/isolamento & purificação , Influenza Humana/prevenção & controle , Orthomyxoviridae/imunologia , Descoberta de Drogas/métodos , Humanos
9.
J Environ Sci (China) ; 58: 239-249, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28774615

RESUMO

Human neural stem cells (hNSCs) are a useful tool to assess the developmental effects of various environmental contaminants; however, the application of hNSCs to evaluate water disinfection byproducts (DBPs) is scarce. Comprehensive toxicological results are essential to the prioritization of DBPs for further testing and regulation. Therefore, this study examines the effects of DBPs on the proliferation and differentiation of hNSCs. Prior to DBP treatment, characteristic protein markers of hNSCs from passages 3 to 6 were carefully examined and it was determined that hNSCs passaged 3 or 4 times maintained stem cell characteristics and can be used for DBP analysis. Two regulated DBPs, monobromoacetic acid (BAA) and monochloroacetic acid (CAA), and two emerging DBPs, 2,6-dibromo-1,4-benzoquinone (2,6-DBBQ) and 2,6-dichloro-1,4-benzoquinone (2,6-DCBQ), were chosen for hNSC treatment. Both 2,6-DBBQ and 2,6-DCBQ induced cell cycle arrest at S-phase at concentrations up to 1µmol/L. Comparatively, BAA and CAA at 0.5µmol/L affected neural differentiation. These results suggest DBP-dependent effects on hNSC proliferation and differentiation. The DBP-induced cell cycle arrest and inhibition of normal hNSC differentiation demonstrate the need to assess the developmental neurotoxicity of DBPs.


Assuntos
Ácido Acético/toxicidade , Benzoquinonas/toxicidade , Desinfetantes/toxicidade , Poluentes Químicos da Água/toxicidade , Desinfecção , Água Potável , Humanos , Células-Tronco Neurais , Purificação da Água
10.
Sci Rep ; 7(1): 7582, 2017 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-28790440

RESUMO

Studies on dsDNA bacteriophages have revealed that a DNA packaging complex assembles at a special vertex called the 'portal vertex' and consists of a portal, a DNA packaging ATPase and other components. AdV protein IVa2 is presumed to function as a DNA packaging ATPase. However, a protein that functions as a portal is not yet identified in AdVs. To identify the AdV portal, we performed secondary structure analysis on a set of AdV proteins and compared them with the clip region of the portal proteins of bacteriophages phi29, SPP1 and T4. Our analysis revealed that the E4 34K protein of HAdV-C5 contains a region of strong similarity with the clip region of the known portal proteins. E4 34K was found to be present in empty as well as mature AdV particles. In addition, E4 34K co-immunoprecipitates and colocalizes with AdV packaging proteins. Immunogold electron microscopy demonstrated that E4 34K is located at a single site on the virus surface. Finally, tertiary structure prediction of E4 34K and its comparison with that of single subunits of Phi29, SPP1 and T4 portal proteins revealed remarkable similarity. In conclusion, our results suggest that E4 34K is the putative AdV portal protein.


Assuntos
Proteínas E4 de Adenovirus/metabolismo , Adenovírus Humanos/fisiologia , Proteínas do Capsídeo/metabolismo , DNA Viral/metabolismo , Montagem de Vírus , Proteínas E4 de Adenovirus/química , Proteínas do Capsídeo/química , Células HEK293 , Humanos , Imunoprecipitação , Microscopia Imunoeletrônica , Estrutura Secundária de Proteína , Estrutura Terciária de Proteína
11.
J Gen Virol ; 98(4): 749-753, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28086071

RESUMO

Bovine adenovirus (AdV) type 3 (BAdV-3) E1 region shares functional homology with E1 of human AdV type C5. Sequence analysis of the BAdV-3 E1 region revealed the presence of a novel 155R ORF that is not observed in other AdVs, on the lower strand antiparallel to a portion of the E1B region. The 155R gene products in BAdV-3-infected cells were identified by Northern blot, reverse transcriptase PCR followed by sequencing and Western blot analysis using the155R-specific antibody. 155R seems to be a late protein and is present in purified BAdV-3 particles. Replication kinetics of BAdV mutants with either one (BAdV/155R/mt1) or two (BAdV/155R/mt2) stop codons in the 155R ORF were comparable to those of BAdV-3, indicating that 155R is not essential for virus replication in cell culture. These results suggest that 155R-deleted BAdV-3 vectors could be generated in a cell line that fully complements BAdV-3 E1 functions.


Assuntos
Adenoviridae/genética , Adenoviridae/fisiologia , Proteínas Estruturais Virais/genética , Proteínas Estruturais Virais/metabolismo , Replicação Viral , Animais , Northern Blotting , Western Blotting , Bovinos , Análise Mutacional de DNA , Perfilação da Expressão Gênica , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA
12.
Antiviral Res ; 139: 161-170, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27889530

RESUMO

DESIGN: The HIV latent CD4+ T cell reservoir is broadly recognized as a barrier to HIV cure. Induction of HIV expression using protein kinase C (PKC) agonists is one approach under investigation for reactivation of latently infected CD4+ T cells (Beans et al., 2013; Abreu et al., 2014; Jiang et al., 2014; Jiang and Dandekar, 2015). We proposed that an increased understanding of the molecular mechanisms of action of PKC agonists was necessary to inform on biological signaling and pharmacodynamic biomarkers. RNA sequencing (RNA Seq) was applied to identify genes and pathways modulated by PKC agonists. METHODS: Human CD4+ T cells were treated ex vivo with Phorbol 12-myristate 13-acetate, prostatin or ingenol-3-angelate. At 3 h and 24 h post-treatment, cells were harvested and RNA-Seq was performed on RNA isolated from cell lysates. The genes differentially expressed across the PKC agonists were validated by quantitative RT-PCR (qPCR). A subset of genes was evaluated for their role in HIV reactivation using siRNA and CRISPR approaches in the Jurkat latency cell model. RESULTS: Treatment of primary human CD4+ T cells with PKC agonists resulted in alterations in gene expression. qPCR of RNA Seq data confirmed upregulation of 24 genes, including CD69, Egr1, Egr2, Egr3, CSF2, DUSP5, and NR4A1. Gene knockdown of Egr1 and Egr3 resulted in reduced expression and decreased HIV reactivation in response to PKC agonist treatment, indicating a potential role for Egr family members in latency reversal. CONCLUSION: Overall, our results offer new insights into the mechanism of action of PKC agonists, biomarkers of pathway engagement, and the potential role of EGR family in HIV reactivation.


Assuntos
HIV-1/fisiologia , Proteína Quinase C/metabolismo , Ativação Viral/efeitos dos fármacos , Latência Viral/efeitos dos fármacos , Biomarcadores , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/virologia , Células Cultivadas , Diterpenos/química , Diterpenos/farmacologia , Agonismo de Drogas , Proteína 1 de Resposta de Crescimento Precoce/genética , Proteína 3 de Resposta de Crescimento Precoce/genética , Expressão Gênica , Infecções por HIV/virologia , Humanos , Células Jurkat , Masculino , Forbóis/farmacologia , Análise de Sequência de RNA
13.
PLoS One ; 11(9): e0163175, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27658193

RESUMO

Reassortment of 2009 (H1N1) pandemic influenza virus (pdH1N1) with other strains may produce more virulent and pathogenic forms, detection and their rapid characterization is critical. In this study, we reported a "one-size-fits-all" approach using a next-generation sequencing (NGS) detection platform to extensively identify influenza viral genomes for diagnosis and determination of novel virulence and drug resistance markers. A de novo module and other bioinformatics tools were used to generate contiguous sequence and identify influenza types/subtypes. Of 162 archived influenza-positive patient specimens, 161(99.4%) were positive for either influenza A or B viruses determined using the NGS assay. Among these, 135(83.3%) were A(H3N2), 14(8.6%) were A(pdH1N1), 2(1.2%) were A(H3N2) and A(pdH1N1) virus co-infections and 10(6.2%) were influenza B viruses. Of the influenza A viruses, 66.7% of A(H3N2) viruses tested had a E627K mutation in the PB2 protein, and 87.8% of the influenza A viruses contained the S31N mutation in the M2 protein. Further studies demonstrated that the NGS assay could achieve a high level of sensitivity and reveal adequate genetic information for final laboratory confirmation. The current diagnostic platform allows for simultaneous identification of a broad range of influenza viruses, monitoring emerging influenza strains with pandemic potential that facilitating diagnostics and antiviral treatment in the clinical setting and protection of the public health.

14.
PLoS One ; 11(6): e0157340, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27314585

RESUMO

HIV-1 subtypes and drug resistance are routinely tested by many international surveillance groups. However, results from different sites often vary. A systematic comparison of results from multiple sites is needed to determine whether a standardized protocol is required for consistent and accurate data analysis. A panel of well-characterized HIV-1 isolates (N = 50) from the External Quality Assurance Program Oversight Laboratory (EQAPOL) was assembled for evaluation at seven international sites. This virus panel included seven subtypes, six circulating recombinant forms (CRFs), nine unique recombinant forms (URFs) and three group O viruses. Seven viruses contained 10 major drug resistance mutations (DRMs). HIV-1 isolates were prepared at a concentration of 107 copies/ml and compiled into blinded panels. Subtypes and DRMs were determined with partial or full pol gene sequences by conventional Sanger sequencing and/or Next Generation Sequencing (NGS). Subtype and DRM results were reported and decoded for comparison with full-length genome sequences generated by EQAPOL. The partial pol gene was amplified by RT-PCR and sequenced for 89.4%-100% of group M viruses at six sites. Subtyping results of majority of the viruses (83%-97.9%) were correctly determined for the partial pol sequences. All 10 major DRMs in seven isolates were detected at these six sites. The complete pol gene sequence was also obtained by NGS at one site. However, this method missed six group M viruses and sequences contained host chromosome fragments. Three group O viruses were only characterized with additional group O-specific RT-PCR primers employed by one site. These results indicate that PCR protocols and subtyping tools should be standardized to efficiently amplify diverse viruses and more consistently assign virus genotypes, which is critical for accurate global subtype and drug resistance surveillance. Targeted NGS analysis of partial pol sequences can serve as an alternative approach, especially for detection of low-abundance DRMs.


Assuntos
Genes pol/genética , Infecções por HIV/genética , HIV-1/genética , Sequenciamento de Nucleotídeos em Larga Escala , Farmacorresistência Viral/genética , Genótipo , Infecções por HIV/virologia , HIV-1/efeitos dos fármacos , HIV-1/patogenicidade , Humanos , Dados de Sequência Molecular , Mutação , Filogenia , Recombinação Genética
15.
Viruses ; 8(4): 96, 2016 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-27077877

RESUMO

Despite significant advancement in vaccine and virus research, influenza continues to be a major public health concern. Each year in the United States of America, influenza viruses are responsible for seasonal epidemics resulting in over 200,000 hospitalizations and 30,000-50,000 deaths. Accurate and early diagnosis of influenza viral infections are critical for rapid initiation of antiviral therapy to reduce influenza related morbidity and mortality both during seasonal epidemics and pandemics. Several different approaches are currently available for diagnosis of influenza infections in humans. These include viral isolation in cell culture, immunofluorescence assays, nucleic acid amplification tests, immunochromatography-based rapid diagnostic tests, etc. Newer diagnostic approaches are being developed to overcome the limitations associated with some of the conventional detection methods. This review discusses diagnostic approaches currently available for detection of influenza viruses in humans.


Assuntos
Influenza Humana/diagnóstico , Influenza Humana/virologia , Orthomyxoviridae/genética , Orthomyxoviridae/imunologia , Animais , Técnicas de Cultura de Células , Técnica Direta de Fluorescência para Anticorpo , Humanos , Imunoensaio , Dispositivos Lab-On-A-Chip , Técnicas de Diagnóstico Molecular , Orthomyxoviridae/isolamento & purificação , Análise de Sequência de DNA , Testes Sorológicos
16.
Environ Sci Technol ; 50(13): 6744-52, 2016 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-26812484

RESUMO

Halobenzoquinones (HBQs) are a structurally diverse class of water disinfection byproducts. Here, we report a systematic study on the effects of isomeric structure and the type and number of halogen substitutions of HBQs on their cytotoxicity, formation of reactive oxygen species (ROS), and genotoxicity. Dynamic responses and IC50 histograms were obtained using real-time cell analysis, clearly ranking the cytotoxicity of the HBQs in Chinese hamster ovary (CHO-K1) cells. Strong isomeric structure effects were shown with 2,5-HBQ isomers inducing greater cytotoxicity than their corresponding 2,6-HBQ isomers (P < 0.05). HBQ-halogen substitution groups also influence cytotoxicity, as cytotoxicity increases across the dihalogenated HBQs: iodo- > bromo- > chloro-HBQs (P < 0.05). Determination of HBQ-induced ROS further supports isomeric structure and halogen substitution effects. HBQ-induced genotoxicity was shown as increased levels of 8-hydroxy-2'-deoxyguanosine and p53 protein. Pearson correlation analysis of the HBQ toxicity measurements with their physicochemical parameters demonstrates that dipole moment and the lowest unoccupied molecular orbital energy are two major structural influences on toxicity (r = -0.721 or -0.766, P < 0.05). Dipole moment also correlates with isomer toxicity. This study suggests that formation and occurrence of highly toxic iodo-HBQs and 2,5-HBQs warrant further investigation to fully assess the impact of HBQs in drinking water.


Assuntos
Desinfecção , Espécies Reativas de Oxigênio/metabolismo , Animais , Benzoquinonas/química , Células CHO , Cricetulus , Água Potável/química , Halogênios
18.
Front Microbiol ; 6: 318, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25954255

RESUMO

The mechanism of genome packaging in adenoviruses (AdVs) is presumed to be similar to that of dsDNA viruses including herpesviruses and dsDNA phages. First, the empty capsids are assembled after which the viral genome is pushed through a unique vertex by a motor which consists of three minimal components: an ATPase, a small terminase and a portal. Various components of this motor exist as ring-like structures forming a central channel through which the DNA travels during packaging. In AdV, the IVa2 protein is believed to function as a packaging ATPase, however, the equivalents of the small terminase and the portal have not been identified in AdVs. IVa2 interacts with another viral protein late region 4 (L4) 33K which is important for genome packaging. Both IVa2 and 33K are expressed at high levels during the late stage of virus infection. The oligomeric state of IVa2 and 33K was analyzed in virus-infected cells, IVa2 and 33K transfected cells, AdV particles, or as recombinant purified proteins. Electron microscopy of the purified proteins showed ring-like oligomers for both proteins which is consistent with their putative roles as a part of the packaging motor. We found that the ATPase activity of IVa2 is stimulated in the presence of 33K and the AdV genome. Our results suggest that the 33K functions analogous to the small terminase proteins and so will be part of the packaging motor complex.

19.
Emerg Infect Dis ; 21(3): 400-8, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25694248

RESUMO

Conventional methods for detection and discrimination of influenza viruses are time consuming and labor intensive. We developed a diagnostic platform for simultaneous identification and characterization of influenza viruses that uses a combination of nanomicroarray for screening and multiplex next-generation sequencing (NGS) assays for laboratory confirmation. The nanomicroarray was developed to target hemagglutinin, neuraminidase, and matrix genes to identify influenza A and B viruses. PCR amplicons synthesized by using an adapted universal primer for all 8 gene segments of 9 influenza A subtypes were detected in the nanomicroarray and confirmed by the NGS assays. This platform can simultaneously detect and differentiate multiple influenza A subtypes in a single sample. Use of these methods as part of a new diagnostic algorithm for detection and confirmation of influenza infections may provide ongoing public health benefits by assisting with future epidemiologic studies and improving preparedness for potential influenza pandemics.


Assuntos
Sequenciamento de Nucleotídeos em Larga Escala , Influenza Humana/diagnóstico , Influenza Humana/virologia , Nanotecnologia , Neuraminidase/genética , Análise de Sequência com Séries de Oligonucleotídeos , Orthomyxoviridae/classificação , Orthomyxoviridae/genética , Genótipo , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Reação em Cadeia da Polimerase Multiplex , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Filogenia
20.
Viruses ; 7(2): 543-58, 2015 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-25664610

RESUMO

BACKGROUND: Retroviruses rely on host factors for cell entry, replication, transcription, and other major steps during their life cycle. Human Immunodeficiency Virus-1 (HIV-1) is well known for utilizing a plethora of strategies to evade the host immune response, including the establishment of latent infection within a subpopulation of susceptible cells. HIV-1 also manipulates cellular factors in latently infected cells and persists for long periods of time, despite the presence of successful highly active antiretroviral therapy (HAART). RESULTS: In this study we demonstrate that Nuclear Factor-IB (NF-IB) is induced during HIV-1 infection and its expression negatively impacts viral replication. During HIV-1 infection in peripheral blood mononuclear cells (PBMCs), and the T cell line, Jurkat or during induction of virus replication in latently infected cells, ACH2 and J1.1, we observed a time-dependent alteration in NF-IB expression pattern that correlated with HIV-1 viral expression. Using the Chip assay, we observed an association of NF-IB with the long terminal repeat region of HIV-1 (LTR) (-386 to -453 nt), and this association negatively correlated with HIV-1 transcription. Furthermore, knock-down of NF-IB levels in J1.1 cells resulted in an increase of HIV-1 levels. Knock-down of NF-IB levels in J-Lat-Tat-GFP (A1), (a Jurkat cell GFP reporter model for latent HIV-1 infection) resulted in an increase in GFP levels, indicating a potential negative regulatory role of NF-IB in HIV-1 replication. CONCLUSION: Overall, our results suggest that NF-IB may play a role in intrinsic antiretroviral defenses against HIV-1. These observations may offer new insights into the correlation of the latently infected host cell types and HIV-1, and help to define new therapeutic approaches for triggering the switch from latency to active replication thereby eliminating HIV-1 latent infection.


Assuntos
Infecções por HIV/metabolismo , Infecções por HIV/virologia , Repetição Terminal Longa de HIV , HIV-1/fisiologia , Fatores de Transcrição NFI/metabolismo , Replicação Viral , Linhagem Celular , Expressão Gênica , Regulação da Expressão Gênica , Inativação Gênica , Infecções por HIV/genética , Humanos , Leucócitos Mononucleares/metabolismo , Leucócitos Mononucleares/virologia , Fatores de Transcrição NFI/genética , Ligação Proteica , Interferência de RNA , Ativação Viral , Latência Viral
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