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1.
Liver Transpl ; 30(7): 728-741, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38315053

RESUMO

Chronic HCV infection induces interferon and dysregulates immune responses through inflammation and chronic antigenic stimulation. Antiviral drugs can cure HCV, providing a unique opportunity to examine the immunological restoration that does and does not occur when a chronic viral infection is eradicated. We quantified blood cytokines levels and used mass cytometry to immunophenotype peripheral blood mononuclear cells before and after HCV cure in 2 groups of patients and controls. At baseline, serum interferon α and soluble CD163 (a macrophage product) were elevated in both liver transplant and nonliver transplant patients compared to controls; the frequencies of several peripheral blood mononuclear cell populations differed from controls; and programmed death protein 1-positivity was increased in nearly all T cell subsets. Many abnormalities persisted after HCV cure, including elevated programmed death protein 1 expression on CD4 naïve and central memory T cells, elevated soluble CD163, and expansion of the plasmablast/plasma cell compartment. Several myeloid-lineage subsets, including Ag-presenting dendritic cells, remained dysregulated. In mechanistic studies, interferon α treatment increased programmed death protein 1 on human T cells and increased T cell receptor signaling. The data identify immunological abnormalities that persist after curative HCV treatment. Before cure, high levels of interferon α may stimulate programmed death protein 1 expression on human T cells, causing persistent functional changes.


Assuntos
Antígenos CD , Antígenos de Diferenciação Mielomonocítica , Antivirais , Hepatite C Crônica , Interferon-alfa , Transplante de Fígado , Humanos , Transplante de Fígado/efeitos adversos , Masculino , Antivirais/uso terapêutico , Pessoa de Meia-Idade , Feminino , Antígenos CD/imunologia , Antígenos CD/sangue , Antígenos CD/metabolismo , Antígenos de Diferenciação Mielomonocítica/sangue , Antígenos de Diferenciação Mielomonocítica/imunologia , Hepatite C Crônica/imunologia , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/sangue , Hepatite C Crônica/cirurgia , Interferon-alfa/uso terapêutico , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Receptor de Morte Celular Programada 1/imunologia , Receptores de Superfície Celular/sangue , Receptores de Superfície Celular/imunologia , Adulto , Estudos de Casos e Controles , Idoso , Hepacivirus/imunologia , Hepacivirus/efeitos dos fármacos , Leucócitos Mononucleares/imunologia , Citocinas/sangue , Imunofenotipagem , Resultado do Tratamento
2.
PLoS Comput Biol ; 17(10): e1009463, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34710081

RESUMO

Experimental data about gene functions curated from the primary literature have enormous value for research scientists in understanding biology. Using the Gene Ontology (GO), manual curation by experts has provided an important resource for studying gene function, especially within model organisms. Unprecedented expansion of the scientific literature and validation of the predicted proteins have increased both data value and the challenges of keeping pace. Capturing literature-based functional annotations is limited by the ability of biocurators to handle the massive and rapidly growing scientific literature. Within the community-oriented wiki framework for GO annotation called the Gene Ontology Normal Usage Tracking System (GONUTS), we describe an approach to expand biocuration through crowdsourcing with undergraduates. This multiplies the number of high-quality annotations in international databases, enriches our coverage of the literature on normal gene function, and pushes the field in new directions. From an intercollegiate competition judged by experienced biocurators, Community Assessment of Community Annotation with Ontologies (CACAO), we have contributed nearly 5,000 literature-based annotations. Many of those annotations are to organisms not currently well-represented within GO. Over a 10-year history, our community contributors have spurred changes to the ontology not traditionally covered by professional biocurators. The CACAO principle of relying on community members to participate in and shape the future of biocuration in GO is a powerful and scalable model used to promote the scientific enterprise. It also provides undergraduate students with a unique and enriching introduction to critical reading of primary literature and acquisition of marketable skills.


Assuntos
Crowdsourcing/métodos , Ontologia Genética , Anotação de Sequência Molecular/métodos , Biologia Computacional , Bases de Dados Genéticas , Humanos , Proteínas/genética , Proteínas/fisiologia
3.
Mod Pathol ; 34(12): 2175-2182, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34381188

RESUMO

There is constant remodeling in a cirrhotic liver resulting in cirrhosis being spatially heterogeneous. The Laennec system, and, more recently the Beijing classification, have been used to sub-classify various degrees of cirrhosis. It is unknown how these two schemes compare with each other, how they are impacted by geographic variation, and how they correlate with clinical outcomes. Five needle biopsies were obtained from 20 explanted cirrhotic HCV livers at the time of transplantation. Collagen proportionate area (CPA) was measured by computerized quantitative morphometry. The Laennec system (4A-4C indicating increasing degrees of cirrhosis) and Beijing classification (P-progressive, R-regressive, I-indeterminate) were assessed and then correlated with CPA. Geographical variation using CPAs was calculated by the coefficient of variation (CoV). CPA of Laennec 4C cirrhosis was higher than 4A (p = 0.00008) or 4B (p = 0.0002). The CPA of the P pattern was greater than the R (p = 0.002) or I patterns (p = 0.037). The mean CoV of the five CPAs was 47.3 ± 4.5%, suggesting a significant degree of geographic variation. There was 100% overlap between the Beijing R pattern and Laennec 4A, and 80% overlap between the P pattern and Laennec 4C. Patients' platelet counts of P pattern were lower than R pattern (p = 0.008) or I pattern (p = 0.024), while Laennec 4C was lower than 4A (p = 0.036) and 4B patients (p = 0.7). There was no correlation between CPA, Laennec stage, or Beijing classification and MELD score, liver weights, total bilirubin, or albumin levels. The Laennec system and the Beijing classification are highly correlated with CPA in cirrhosis. This study confirms that there is a significant degree of geographic variation in terms of fibrosis content and cirrhosis morphology throughout the liver.


Assuntos
Cirrose Hepática/patologia , Fígado/patologia , Idoso , Biópsia por Agulha , Feminino , Hepatite C/complicações , Humanos , Fígado/cirurgia , Fígado/virologia , Cirrose Hepática/classificação , Cirrose Hepática/cirurgia , Cirrose Hepática/virologia , Transplante de Fígado , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Índice de Gravidade de Doença
4.
PLoS Pathog ; 15(7): e1007935, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31356648

RESUMO

Plasmacytoid dendritic cells (pDCs) are "natural" interferon α (IFNα)-producing cells. Despite their importance to antiviral defense, autoimmunity, and ischemic liver graft injury, because DC subsets are rare and heterogeneous, basic questions about liver pDC function and capacity to make cytokines remain unanswered. Previous investigations failed to consistently detect IFNα mRNA in HCV-infected livers, suggesting that pDCs may be incapable of producing IFNα. We used a combination of molecular, biochemical, cytometric, and high-dimensional techniques to analyze DC frequencies/functions in liver and peripheral blood mononuclear cells (PBMCs) of hepatitis C virus (HCV)-infected patients, to examine correlations between DC function and gene expression of matched whole liver tissue and liver mononuclear cells (LMCs), and to determine if pDCs can produce multiple cytokines. T cells often produce multiple cytokines/chemokines but until recently technical limitations have precluded tests of polyfunctionality in individual pDCs. Mass cytometry (CyTOF) revealed that liver pDCs are the only LMC that produces detectable amounts of IFNα in response TLR-7/8 stimulation. Liver pDCs secreted large quantities of IFNα (~2 million molecules of IFNα/cell/hour) and produced more IFNα than PBMCs after stimulation, p = 0.0001. LMCs secreted >14-fold more IFNα than IFNλ in 4 hours. Liver pDC frequency positively correlated with whole liver expression of "IFNα-response" pathway (R2 = 0.58, p = 0.007) and "monocyte surface" signature (R2 = 0.54, p = 0.01). Mass cytometry revealed that IFNα-producing pDCs were highly polyfunctional; >90% also made 2-4 additional cytokines/chemokines of our test set of 10. Liver BDCA1 DCs, but not BDCA3 DCs, were similarly polyfunctional. pDCs from a healthy liver were also polyfunctional. Our data show that liver pDCs retain the ability to make abundant IFNα during chronic HCV infection and produce many other immune modulators. Polyfunctional liver pDCs are likely to be key drivers of inflammation and immune activation during chronic HCV infection.


Assuntos
Citocinas/biossíntese , Células Dendríticas/imunologia , Hepatite C Crônica/imunologia , Interferon-alfa/biossíntese , Idoso , Antígenos CD1/sangue , Antígenos CD1/metabolismo , Antígenos de Superfície/sangue , Antígenos de Superfície/metabolismo , Quimiocinas/biossíntese , Células Dendríticas/classificação , Células Dendríticas/patologia , Feminino , Glicoproteínas/sangue , Glicoproteínas/metabolismo , Hepatite C Crônica/sangue , Hepatite C Crônica/patologia , Humanos , Interferon-alfa/sangue , Interferon gama/biossíntese , Interferon gama/sangue , Fígado/imunologia , Fígado/patologia , Masculino , Pessoa de Meia-Idade , Trombomodulina
5.
Mol Plant Microbe Interact ; 31(4): 471-480, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29143556

RESUMO

Transcription activator-like effectors (TALEs) are proteins found in the genus Xanthomonas of phytopathogenic bacteria. These proteins enter the nucleus of cells in the host plant and can induce the expression of susceptibility genes (S genes), triggering disease. TALEs bind the promoter region of S genes following a specific code, which allows the prediction of binding sites based on TALEs amino acid sequences. New candidate S genes can then be discovered by finding the intersection between genes induced in the presence of TALEs and genes containing predicted effector binding elements. By contrasting differential expression data and binding site predictions across different datasets, patterns of TALE diversification or convergence may be unveiled, but this requires the seamless integration of different genomic and transcriptomic data. With this in mind, we present daTALbase, a curated relational database that integrates TALE-related data including bacterial TALE sequences, plant promoter sequences, predicted TALE binding sites, transcriptomic data of host plants in response to TALE-harboring bacteria, and other associated data. The database can be explored to uncover new candidate S genes as well as to study variation in TALE repertories and their corresponding targets. The first version of the database here presented includes data for Oryza sp.-Xanthomonas pv. oryzae interactions. Future versions of the database will incorporate information for other pathosystems involving TALEs.


Assuntos
Proteínas de Bactérias/metabolismo , Bases de Dados Genéticas , Genoma Bacteriano , Efetores Semelhantes a Ativadores de Transcrição/metabolismo , Transcriptoma/genética , Genes Bacterianos , Internet , Filogenia , Interface Usuário-Computador , Xanthomonas/genética
6.
New Phytol ; 219(1): 391-407, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29677397

RESUMO

Xanthomonas transcription activator-like effectors (TALEs) are injected inside plant cells to promote host susceptibility by enhancing transcription of host susceptibility genes. TALE-encoding (tal) genes were thought to be absent from Brassicaceae-infecting Xanthomonas campestris (Xc) genomes based on four reference genomic sequences. We discovered tal genes in 26 of 49 Xc strains isolated worldwide and used a combination of single molecule real time (SMRT) and tal amplicon sequencing to yield a near-complete description of the TALEs found in Xc (Xc TALome). The 53 sequenced tal genes encode 21 distinct DNA binding domains that sort into seven major DNA binding specificities. In silico analysis of the Brassica rapa promoterome identified a repertoire of predicted TALE targets, five of which were experimentally validated using quantitative reverse transcription polymerase chain reaction. The Xc TALome shows multiple signs of DNA rearrangements that probably drove its evolution from two ancestral tal genes. We discovered that Tal12a and Tal15a of Xcc strain Xca5 contribute together in the development of disease symptoms on susceptible B. oleracea var. botrytis cv Clovis. This large and polymorphic repertoire of TALEs opens novel perspectives for elucidating TALE-mediated susceptibility of Brassicaceae to black rot disease and for understanding the molecular processes underlying TALE evolution.


Assuntos
Interações Hospedeiro-Patógeno/genética , Efetores Semelhantes a Ativadores de Transcrição/genética , Xanthomonas campestris/genética , Xanthomonas campestris/patogenicidade , Brassica/microbiologia , Genoma Bacteriano , Filogenia , Doenças das Plantas/microbiologia
7.
Hepatology ; 66(2): 357-370, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-27642141

RESUMO

Hepatitis C virus (HCV) is unique among RNA viruses in its ability to establish chronic infection in the majority of exposed adults. HCV persists in the liver despite interferon (IFN)-stimulated gene (ISG) induction; robust induction actually predicts treatment failure and viral persistence. It is unclear which forms of HCV RNA are associated with ISG induction and IFN resistance during natural infections. To thoroughly delineate HCV RNA populations, we developed conditions that fully separate the strands of long double-stranded RNA (dsRNA) and allow the released RNAs to be quantified in reverse transcription/polymerase chain reaction assays. These methods revealed that dsRNA, a pathogen-associated molecular pattern (PAMP), comprised 52% (standard deviation, 28%) of the HCV RNA in the livers of patients with chronic infection. HCV dsRNA was proportionally higher in patients with the unfavorable IL28B TT (rs12979860) genotype. Higher ratios of HCV double-stranded to single-stranded RNA (ssRNA) correlated positively with ISG induction. In Huh-7.5 cells, IFN treatment increased the total amount of HCV dsRNA through a process that required de novo viral RNA synthesis and shifted the ratio of viral dsRNA/ssRNA in favor of dsRNA. This shift was blocked by ribavirin (RBV), an antiviral drug that reduces relapse in HCV patients. Northern blotting established that HCV dsRNA contained genome-length minus strands. CONCLUSION: HCV dsRNA is the predominant form in the HCV-infected liver and has features of both a PAMP and a genomic reservoir. Interferon treatment increased rather than decreased HCV dsRNA. This unexpected finding suggests that HCV produces dsRNA in response to IFN, potentially to antagonize antiviral defenses. (Hepatology 2017;66:357-370).


Assuntos
Antivirais/farmacologia , Hepacivirus/genética , Hepatite C/patologia , Interferon-alfa/farmacologia , RNA de Cadeia Dupla/genética , Adulto , Biópsia por Agulha , Western Blotting , Células Cultivadas , Feminino , Citometria de Fluxo , Hepacivirus/efeitos dos fármacos , Hepatite C/tratamento farmacológico , Hepatite C/genética , Hepatócitos/citologia , Hepatócitos/efeitos dos fármacos , Humanos , Imuno-Histoquímica , Masculino , RNA de Cadeia Dupla/efeitos dos fármacos , RNA Viral/efeitos dos fármacos , RNA Viral/genética , Valores de Referência , Sensibilidade e Especificidade
8.
Med Care ; 55 Suppl 7 Suppl 1: S33-S36, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28410338

RESUMO

BACKGROUND: Opioid overdose and other related harms are a major source of morbidity and mortality among US Veterans, in part due to high-risk opioid prescribing. OBJECTIVES: We sought to determine whether having multiple sources of payment for opioids-as a marker for out-of-system access-is associated with risky opioid therapy among veterans. RESEARCH DESIGN: Cross-sectional study examining the association between multiple sources of payment and risky opioid therapy among all individuals with Veterans Health Administration (VHA) payment for opioid analgesic prescriptions in Kentucky during fiscal year 2014-2015. MEASURES: Source of payment categories: (1) VHA only source of payment (sole source); (2) sources of payment were VHA and at least 1 cash payment [VHA+cash payment(s)] whether or not there was a third source of payment; and (3) at least one other noncash source: Medicare, Medicaid, or private insurance [VHA+noncash source(s)]. Our outcomes were 2 risky opioid therapies: combination opioid/benzodiazepine therapy and high-dose opioid therapy, defined as morphine equivalent daily dose ≥90 mg. RESULTS: Of the 14,795 individuals in the analytic sample, there were 81.9% in the sole source category, 6.6% in the VHA+cash payment(s) category, and 11.5% in the VHA+noncash source(s) category. In logistic regression, controlling for age and sex, persons with multiple payment sources had significantly higher odds of each risky opioid therapy, with those in the VHA+cash having significantly higher odds than those in the VHA+noncash source(s) group. CONCLUSIONS: Prescribers should examine the prescription monitoring program as multiple payment sources increase the odds of risky opioid therapy.


Assuntos
Analgésicos Opioides/administração & dosagem , Analgésicos Opioides/economia , Reembolso de Seguro de Saúde , United States Department of Veterans Affairs , Saúde dos Veteranos , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Humanos , Reembolso de Seguro de Saúde/estatística & dados numéricos , Kentucky , Masculino , Pessoa de Meia-Idade , Assunção de Riscos , Estados Unidos
9.
Clin Infect Dis ; 62(12): 1497-1504, 2016 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-26936665

RESUMO

BACKGROUND: Patients with hepatitis C virus (HCV) with or without human immunodeficiency virus (HIV) achieve high sustained virological response (SVR) rates on sofosbuvir (SOF)-containing regimens in clinical trials. Real world data on patients coinfected with HCV and HIV treated with SOF-based regimens are lacking. METHODS: This observational cohort study included HIV/HCV-coinfected adults with genotype 1 HCV who initiated treatment with a SOF-containing regimen between December 2013 and December 2014 (n = 89) at the Mount Sinai Hospital or the Brooklyn Hospital Center. The primary outcome was SVR at 12 weeks after the end of treatment. The secondary outcomes were risk factors for treatment failure, serious adverse events, and side effects. A post hoc per protocol analysis of SVR was performed on patients who completed treatment and follow-up. RESULTS: In an intention-to-treat analysis, SVR rates were 76% (31/41) for simeprevir (SMV)/SOF, 94% (16/17) for SMV/SOF/ribavirin (RBV), and 52% (16/31) for SOF/RBV. The SVR rates of SMV/SOF/RBV and SMV/SOF did not differ significantly in this small study (P = .15). However the SVR rate of SMV/SOF/RBV was higher than that of SOF/RBV (P < .01). In a per protocol analysis, SMV/SOF/RBV had a higher SVR rate than SOF/RBV: 100% (16/16) vs 57% (16/28) (P < .01). The most commonly reported adverse effects were rash, pruritus, fatigue, and insomnia. One patient who had decompensated cirrhosis prior to treatment initiation died after receiving SMV/SOF. CONCLUSIONS: SMV/SOF ± RBV is an effective option with minimal adverse effects for most HIV-positive patients with genotype 1 HCV. SMV should be used with caution in patients with decompensated cirrhosis.


Assuntos
Antivirais/uso terapêutico , Infecções por HIV/tratamento farmacológico , Infecções por HIV/virologia , Hepatite C/tratamento farmacológico , Hepatite C/virologia , Sofosbuvir/uso terapêutico , Antivirais/administração & dosagem , Antivirais/efeitos adversos , Feminino , Infecções por HIV/epidemiologia , HIV-1 , Hepacivirus , Hepatite C/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Cidade de Nova Iorque/epidemiologia , Fatores de Risco , Simeprevir/administração & dosagem , Simeprevir/efeitos adversos , Simeprevir/uso terapêutico , Sofosbuvir/administração & dosagem , Sofosbuvir/efeitos adversos , Resultado do Tratamento , Carga Viral
10.
PLoS Pathog ; 10(2): e1003972, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24586171

RESUMO

Bacterial leaf streak of rice, caused by Xanthomonas oryzae pv. oryzicola (Xoc) is an increasingly important yield constraint in this staple crop. A mesophyll colonizer, Xoc differs from X. oryzae pv. oryzae (Xoo), which invades xylem to cause bacterial blight of rice. Both produce multiple distinct TAL effectors, type III-delivered proteins that transactivate effector-specific host genes. A TAL effector finds its target(s) via a partially degenerate code whereby the modular effector amino acid sequence identifies nucleotide sequences to which the protein binds. Virulence contributions of some Xoo TAL effectors have been shown, and their relevant targets, susceptibility (S) genes, identified, but the role of TAL effectors in leaf streak is uncharacterized. We used host transcript profiling to compare leaf streak to blight and to probe functions of Xoc TAL effectors. We found that Xoc and Xoo induce almost completely different host transcriptional changes. Roughly one in three genes upregulated by the pathogens is preceded by a candidate TAL effector binding element. Experimental analysis of the 44 such genes predicted to be Xoc TAL effector targets verified nearly half, and identified most others as false predictions. None of the Xoc targets is a known bacterial blight S gene. Mutational analysis revealed that Tal2g, which activates two genes, contributes to lesion expansion and bacterial exudation. Use of designer TAL effectors discriminated a sulfate transporter gene as the S gene. Across all targets, basal expression tended to be higher than genome-average, and induction moderate. Finally, machine learning applied to real vs. falsely predicted targets yielded a classifier that recalled 92% of the real targets with 88% precision, providing a tool for better target prediction in the future. Our study expands the number of known TAL effector targets, identifies a new class of S gene, and improves our ability to predict functional targeting.


Assuntos
Proteínas de Bactérias/genética , Genes de Plantas , Interações Hospedeiro-Patógeno/genética , Oryza/microbiologia , Doenças das Plantas/genética , Xanthomonas/genética , Sequência de Aminoácidos , Sequência de Bases , Análise Mutacional de DNA , Resistência à Doença , Regulação da Expressão Gênica de Plantas , Técnicas de Inativação de Genes , Análise de Sequência com Séries de Oligonucleotídeos , Folhas de Planta/microbiologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa
11.
J Hepatol ; 63(6): 1323-33, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26220749

RESUMO

BACKGROUND & AIMS: Although patients infected by genotype 1b hepatitis C virus (HCV) with Q(70) and/or M(91)core gene mutations have an almost five-fold increased risk of developing hepatocellular carcinoma (HCC) and increased insulin resistance, the absence of a suitable experimental system has precluded direct experimentation on the effects of these mutations on cellular gene expression. METHODS: HuH7 cells were treated long-term with human serum to induce differentiation and to produce a model system for testing high-risk and control HCV. For clinical validation, profiles of infected cells were compared to each other and to those of liver biopsies of patients with early-stage HCV-related cirrhosis followed prospectively for up to 23 years (n=216). RESULTS: Long-term culture in human serum produced growth-arrested, hepatocyte-like cells whose gene profile overlapped significantly with that of primary human hepatocytes. High-risk (Q(70)/M(91)) and control (R(70)/L(91)) viruses had dramatically different effects on gene expression of these cells. The high-risk virus enhanced expression of pathways associated with cancer and type II diabetes, while the control virus enhanced pathways associated with oxidative phosphorylation. Of special clinical relevance, the transcriptome of cells replicating the high-risk virus correlated significantly with an HCC high-risk profile in patients (Bonferroni-corrected p=0.03), whereas no such association was observed for non-HCC-related clinical outcomes. CONCLUSIONS: The cell-based system allowed direct head-to-head comparison of HCV variants, and provided experimental support for previous clinical data indicating an oncogenic effect of core gene mutations. This simple experimental system distinguished HCV variants and will enable future mechanistic analysis and exploration of interventional approaches.


Assuntos
Carcinoma Hepatocelular/etiologia , Carcinoma Hepatocelular/virologia , Genes Virais , Hepacivirus/genética , Hepacivirus/patogenicidade , Antígenos do Núcleo do Vírus da Hepatite B/genética , Neoplasias Hepáticas/etiologia , Neoplasias Hepáticas/virologia , Mutação , Proteínas do Core Viral/genética , Técnicas de Cultura de Células , Diferenciação Celular , Linhagem Celular , Variação Genética , Genótipo , Hepacivirus/fisiologia , Hepatite C Crônica/complicações , Hepatite C Crônica/virologia , Hepatócitos/metabolismo , Hepatócitos/patologia , Hepatócitos/virologia , Humanos , Cirrose Hepática/complicações , Cirrose Hepática/virologia , Oncogenes , Estudos Prospectivos , Fatores de Risco , Transcriptoma , Virulência/genética , Replicação Viral
13.
J Orthop Traumatol ; 16(2): 151-9, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25421865

RESUMO

BACKGROUND: Recombinant human bone morphogenetic protein-2 (rhBMP-2) is particularly effective in improving osteogenesis in patients with diminished bone healing capabilities, such as individuals with type 1 diabetes mellitus (T1DM) who have impaired bone healing capabilities and increased risk of developing osteoporosis. This study measured the effects of rhBMP-2 treatment on osteogenesis by observing the dose-dependent effect of localized delivery of rhBMP-2 on biomechanical parameters of bone using a hydroxyapatite/tri-calcium phosphate (HA/TCP) carrier in a T1DM-related osteoporosis animal model. MATERIALS AND METHODS: Two different doses of rhBMP-2 (LD low dose, HD high dose) with a HA/TCP carrier were injected into the femoral intramedullary canal of rats with T1DM-related osteoporosis. Two more diabetic rat groups were injected with saline alone and with HA/TCP carrier alone. Radiographs and micro-computed tomography were utilized for qualitative assessment of bone mineral density (BMD). Biomechanical testing occurred at 4- and 8-week time points; parameters tested included torque to failure, torsional rigidity, shear stress, and shear modulus. RESULTS: At the 4-week time point, the LD and HD groups both exhibited significantly higher BMD than controls; at the 8-week time point, the HD group exhibited significantly higher BMD than controls. Biomechanical testing revealed dose-dependent, higher trends in all parameters tested at the 4- and 8-week time points, with minimal significant differences. CONCLUSIONS: Groups treated with rhBMP-2 demonstrated improved bone mineral density at both 4 and 8 weeks compared to control saline groups, in addition to strong trends towards improvement of intrinsic and extrinsic biomechanical properties when compared to control groups. Data revealed trends toward dose-dependent increases in peak torque, torsional rigidity, shear stress, and shear modulus 4 weeks after rhBMP-2 treatment. LEVEL OF EVIDENCE: Not applicable.


Assuntos
Proteína Morfogenética Óssea 2/farmacologia , Fosfatos de Cálcio/farmacologia , Diabetes Mellitus Tipo 1/complicações , Durapatita/farmacologia , Fêmur/patologia , Osteoporose/tratamento farmacológico , Osteoporose/etiologia , Fator de Crescimento Transformador beta/farmacologia , Animais , Fenômenos Biomecânicos , Densidade Óssea/efeitos dos fármacos , Modelos Animais de Doenças , Masculino , Osteogênese/efeitos dos fármacos , Ratos Wistar , Proteínas Recombinantes/farmacologia , Microtomografia por Raio-X
14.
Nucleic Acids Res ; 40(Web Server issue): W117-22, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22693217

RESUMO

Transcription activator-like (TAL) effectors are repeat-containing proteins used by plant pathogenic bacteria to manipulate host gene expression. Repeats are polymorphic and individually specify single nucleotides in the DNA target, with some degeneracy. A TAL effector-nucleotide binding code that links repeat type to specified nucleotide enables prediction of genomic binding sites for TAL effectors and customization of TAL effectors for use in DNA targeting, in particular as custom transcription factors for engineered gene regulation and as site-specific nucleases for genome editing. We have developed a suite of web-based tools called TAL Effector-Nucleotide Targeter 2.0 (TALE-NT 2.0; https://boglab.plp.iastate.edu/) that enables design of custom TAL effector repeat arrays for desired targets and prediction of TAL effector binding sites, ranked by likelihood, in a genome, promoterome or other sequence of interest. Search parameters can be set by the user to work with any TAL effector or TAL effector nuclease architecture. Applications range from designing highly specific DNA targeting tools and identifying potential off-target sites to predicting effector targets important in plant disease.


Assuntos
Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/metabolismo , Software , Transativadores/química , Transativadores/metabolismo , Algoritmos , Sítios de Ligação , DNA/química , DNA/metabolismo , Internet , Engenharia de Proteínas , Sequências Repetitivas de Aminoácidos , Análise de Sequência de DNA , Interface Usuário-Computador
15.
J Infect Dis ; 208(5): 830-8, 2013 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-23757341

RESUMO

BACKGROUND: Clinical studies have shown faster disease progression and stronger immune activation in human immunodeficiency virus (HIV)-1-infected females when compared with males for the same level of HIV-1 replication. Here we determine whether the elevated levels of HIV-1-induced interferon-alpha (IFN-α) production observed in females are associated with higher interferon-stimulated gene (ISG) expression levels in T cells, hence suggesting type-I IFN as a mechanism for the higher HIV-1-associated immune activation observed. METHODS: T-cell and dendritic cell populations were isolated from treatment-naive chronically HIV-1-infected individuals enrolled in the Adult Clinical Trials Group 384 by fluorescence-activated cell sorting. The expression of 98 genes involved in Toll-like receptor and type I IFN signaling pathways were quantified using Nanostring technology. RESULTS: Several ISGs were significantly correlated with HIV-1 viral load and/or CD4(+) T-cell count. Higher expression levels of a subset of these ISGs were observed in cells derived from females as compared to males after adjusting for viral load and were correlated to higher levels of T-cell activation. CONCLUSION: These data show that higher IFN-α production is associated with higher ex vivo expression of several ISGs in females. This might contribute to higher levels of immune activation and the observed faster HIV-1 disease progression in females for a given level of viral replication.


Assuntos
Regulação da Expressão Gênica , Infecções por HIV/imunologia , HIV-1/imunologia , Interferon-alfa/imunologia , Linfócitos T/imunologia , Adulto , Células Cultivadas , Células Dendríticas/imunologia , Feminino , Perfilação da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade
16.
Addict Biol ; 18(3): 480-95, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-22804800

RESUMO

Neuroadaptations in the ventral striatum (VS) and ventral midbrain (VMB) following chronic opioid administration are thought to contribute to the pathogenesis and persistence of opiate addiction. In order to identify candidate genes involved in these neuroadaptations, we utilized a behavior-genetics strategy designed to associate contingent intravenous drug self-administration with specific patterns of gene expression in inbred mice differentially predisposed to the rewarding effects of morphine. In a Yoked-control paradigm, C57BL/6J mice showed clear morphine-reinforced behavior, whereas DBA/2J mice did not. Moreover, the Yoked-control paradigm revealed the powerful consequences of self-administration versus passive administration at the level of gene expression. Morphine self-administration in the C57BL/6J mice uniquely up- or down-regulated 237 genes in the VS and 131 genes in the VMB. Interestingly, only a handful of the C57BL/6J self-administration genes (<3%) exhibited a similar expression pattern in the DBA/2J mice. Hence, specific sets of genes could be confidently assigned to regional effects of morphine in a contingent- and genotype-dependent manner. Bioinformatics analysis revealed that neuroplasticity, axonal guidance and micro-RNAs (miRNAs) were among the key themes associated with drug self-administration. Noteworthy were the primary miRNA genes H19 and micro-RNA containing gene (Mirg), processed, respectively, to mature miRNAs miR-675 and miR-154, because they are prime candidates to mediate network-like changes in responses to chronic drug administration. These miRNAs have postulated roles in dopaminergic neuron differentiation and mu-opioid receptor regulation. The strategic approach designed to focus on reinforcement-associated genes provides new insight into the role of neuroplasticity pathways and miRNAs in drug addiction.


Assuntos
MicroRNAs/genética , Dependência de Morfina/genética , Morfina/farmacologia , Entorpecentes/farmacologia , Plasticidade Neuronal/efeitos dos fármacos , Adaptação Fisiológica , Análise de Variância , Animais , Axônios/efeitos dos fármacos , Infusões Intravenosas , Camundongos , Camundongos Endogâmicos C57BL , Análise em Microsséries , Reforço Psicológico , Recompensa , Autoadministração
17.
Nucleic Acids Res ; 39(12): e82, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21493687

RESUMO

TALENs are important new tools for genome engineering. Fusions of transcription activator-like (TAL) effectors of plant pathogenic Xanthomonas spp. to the FokI nuclease, TALENs bind and cleave DNA in pairs. Binding specificity is determined by customizable arrays of polymorphic amino acid repeats in the TAL effectors. We present a method and reagents for efficiently assembling TALEN constructs with custom repeat arrays. We also describe design guidelines based on naturally occurring TAL effectors and their binding sites. Using software that applies these guidelines, in nine genes from plants, animals and protists, we found candidate cleavage sites on average every 35 bp. Each of 15 sites selected from this set was cleaved in a yeast-based assay with TALEN pairs constructed with our reagents. We used two of the TALEN pairs to mutate HPRT1 in human cells and ADH1 in Arabidopsis thaliana protoplasts. Our reagents include a plasmid construct for making custom TAL effectors and one for TAL effector fusions to additional proteins of interest. Using the former, we constructed de novo a functional analog of AvrHah1 of Xanthomonas gardneri. The complete plasmid set is available through the non-profit repository AddGene and a web-based version of our software is freely accessible online.


Assuntos
Proteínas de Ligação a DNA/química , Desoxirribonucleases de Sítio Específico do Tipo II/metabolismo , Marcação de Genes , Engenharia de Proteínas/métodos , Sequência de Aminoácidos , Arabidopsis/genética , Sequência de Bases , Clivagem do DNA , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Desoxirribonucleases de Sítio Específico do Tipo II/química , Desoxirribonucleases de Sítio Específico do Tipo II/genética , Humanos , Dados de Sequência Molecular , Mutagênese , Protoplastos/metabolismo , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/metabolismo , Sequências Repetitivas de Aminoácidos , Software , Transativadores/química , Transativadores/genética , Transativadores/metabolismo , Xanthomonas/genética
18.
Genes (Basel) ; 14(3)2023 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-36981000

RESUMO

Inhalation of asbestos fibres can cause lung inflammation and the later development of asbestosis, lung cancer, and mesothelioma, and the use of asbestos is banned in many countries. In most countries, large amounts of asbestos exists within building stock, buried in landfills, and in contaminated soil. Mechanical, thermal, and chemical treatment options do exist, but these are expensive, and they are not effective for contaminated soil, where only small numbers of asbestos fibres may be present in a large volume of soil. Research has been underway for the last 20 years into the potential use of microbial action to remove iron and other metal cations from the surface of asbestos fibres to reduce their toxicity. To access sufficient iron for metabolism, many bacteria and fungi produce organic acids, or iron-chelating siderophores, and in a growing number of experiments these have been found to degrade asbestos fibres in vitro. This paper uses the internal transcribed spacer (ITS) and 16S amplicon sequencing to investigate the fungal and bacterial diversity found on naturally-occurring asbestos minerals, asbestos-containing building materials, and asbestos-contaminated soils with a view to later selectively culturing promising species, screening them for siderophore production, and testing them with asbestos fibres in vitro. After filtering, 895 ITS and 1265 16S amplicon sequencing variants (ASVs) were detected across the 38 samples, corresponding to a range of fungal, bacteria, cyanobacterial, and lichenized fungal species. Samples from Auckland (North Island, New Zealand) asbestos cement, Auckland asbestos-contaminated soils, and raw asbestos rocks from Kahurangi National Park (South Island, New Zealand) were comprised of very different microbial communities. Five of the fungal species detected in this study are known to produce siderophores.


Assuntos
Amianto , Sideróforos , Nova Zelândia , Ferro/metabolismo , Bactérias/genética , Bactérias/metabolismo , Solo
19.
Cancer Med ; 12(9): 10175-10186, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37078924

RESUMO

BACKGROUND: Successful treatment of hepatitis C reduces liver inflammation and fibrosis; however, patients remain at risk of developing hepatocellular carcinoma (HCC). AIMS: To identify risk factors for new-onset HCC in patients cured of hepatitis C. METHODS: Imaging, histological, and clinical data on patients whose first HCC was diagnosed >12 months of post-SVR were analyzed. Histology of 20 nontumor tissues was analyzed in a blinded manner using the Knodel/Ishak/HAI system for necroinflammation and fibrosis/cirrhosis stage and the Brunt system for steatosis/steatohepatitis. Factors associated with post-SVR HCC were identified by comparison with HALT-C participants who did not develop post-SVR HCC. RESULTS: Hepatocellular carcinoma was diagnosed in 54 patients (45 M/9F), a median of 6 years of post-SVR [interquartile range (IQR) =1.4-10y] at a median age of 61 years (IQR, 59-67). Approximately one-third lacked cirrhosis, and only 11% had steatosis on imaging. The majority (60%) had no steatosis/steatohepatitis in histopathology. The median HAI score was 3 (1.25-4), indicating mild necroinflammation. In a multivariable logistic regression model, post-SVR HCC was positively associated with non-Caucasian race (p = 0.03), smoking (p = 0.03), age > 60 years at HCC diagnosis (p = 0.03), albumin<3.5 g/dL (p = 0.02), AST/ALT>1 (p = 0.05), and platelets <100 × 103 cells/µL (p < 0.001). Alpha fetoprotein ≥4.75 ng/mL had 90% specificity and 71% sensitivity for HCC occurrence. Noncirrhotic patients had larger tumors (p = 0.002) and a higher prevalence of vascular invasion (p = 0.016) than cirrhotic patients. CONCLUSIONS: One-third of patients with post-SVR HCC did not have liver cirrhosis; most had no steatosis/steatohepatitis. Hepatocellular carcinomas were more advanced in noncirrhotic patients. Results support AFP as a promising marker of post-SVR HCC risk.


Assuntos
Carcinoma Hepatocelular , Fígado Gorduroso , Hepatite C Crônica , Hepatite C , Neoplasias Hepáticas , Humanos , Pessoa de Meia-Idade , Idoso , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/epidemiologia , Carcinoma Hepatocelular/etiologia , Hepatite C Crônica/complicações , Hepatite C Crônica/tratamento farmacológico , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/epidemiologia , Neoplasias Hepáticas/etiologia , Antivirais/uso terapêutico , Resposta Viral Sustentada , Fatores de Risco , Hepatite C/complicações , Cirrose Hepática/complicações , Fígado Gorduroso/complicações , Fígado Gorduroso/tratamento farmacológico , Hepacivirus
20.
New Phytol ; 195(4): 883-893, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22747776

RESUMO

Xanthomonas transcription activator-like (TAL) effectors promote disease in plants by binding to and activating host susceptibility genes. Plants counter with TAL effector-activated executor resistance genes, which cause host cell death and block disease progression. We asked whether the functional specificity of an executor gene could be broadened by adding different TAL effector binding elements (EBEs) to it. We added six EBEs to the rice Xa27 gene, which confers resistance to strains of the bacterial blight pathogen Xanthomonas oryzae pv. oryzae (Xoo) that deliver the TAL effector AvrXa27. The EBEs correspond to three other effectors from Xoo strain PXO99(A) and three from strain BLS256 of the bacterial leaf streak pathogen Xanthomonas oryzae pv. oryzicola (Xoc). Stable integration into rice produced healthy lines exhibiting gene activation by each TAL effector, and resistance to PXO99(A) , a PXO99(A) derivative lacking AvrXa27, and BLS256, as well as two other Xoo and 10 Xoc strains virulent toward wildtype Xa27 plants. Transcripts initiated primarily at a common site. Sequences in the EBEs were found to occur nonrandomly in rice promoters, suggesting an overlap with endogenous regulatory sequences. Thus, executor gene specificity can be broadened by adding EBEs, but caution is warranted because of the possible coincident introduction of endogenous regulatory elements.


Assuntos
Resistência à Doença/genética , Genes de Plantas/genética , Oryza/genética , Oryza/microbiologia , Doenças das Plantas/microbiologia , Transativadores/metabolismo , Xanthomonas/fisiologia , Sistemas de Secreção Bacterianos/genética , Sequência de Bases , Sítios de Ligação , Regulação da Expressão Gênica de Plantas , Engenharia Genética , Dados de Sequência Molecular , Mutagênese Insercional , Doenças das Plantas/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , Regiões Promotoras Genéticas/genética , Especificidade da Espécie , Sítio de Iniciação de Transcrição , Transcrição Gênica
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