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1.
Sci Rep ; 10(1): 7499, 2020 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-32372013

RESUMO

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

2.
Br J Surg ; 107(11): 1489-1499, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32352164

RESUMO

BACKGROUND: Insulinomas are found in 10-15 per cent of patients with multiple endocrine neoplasia type 1 (MEN1) and lead to life-threatening hypoglycaemia. Surgical outcome and the optimal surgical strategy for MEN1-related insulinoma are unknown. METHODS: Patients with MEN1-related insulinomas were identified in 46 centres in Europe and North America between 1990 and 2016. Insulinomas were considered localized if the lesion was in the pancreatic head or body/tail. Patients with pancreatic neuroendocrine tumours throughout the pancreas were suspected of having multifocal insulinoma. The primary outcome was postoperative hypoglycaemia, defined as persistent hypoglycaemia, or recurrent hypoglycaemia caused by a new insulinoma or insulin-producing liver metastases. Hypoglycaemia-free survival was estimated by the Kaplan-Meier method. RESULTS: Ninety-six patients underwent resection for MEN1-related insulinoma. Sixty-three and 33 patients had localized and multifocal insulinomas respectively. After a median follow-up of 8 (range 1-22) years, one patient (1 per cent) had persistent disease and six (6 per cent) had developed recurrent disease, of whom four had a new insulinoma. The 10-year hypoglycaemia-free survival rate was 91 (95 per cent c.i. 80 to 96) per cent. Of those with localized disease, 46 patients underwent pancreatic resection and 17 enucleation. One of these patients had persistent disease and one developed recurrent insulinoma. Among patients with multifocal disease, three developed new insulinomas and two developed insulin-producing liver metastases. CONCLUSION: Surgery for MEN1-related insulinoma is more successful than previously thought.


ANTECEDENTES: Del 10% al 15% de los pacientes con MEN1 presentan insulinomas que pueden desencadenar una hipoglucemia potencialmente mortal. Se desconoce el resultado de la cirugía y la estrategia quirúrgica óptima para el tratamiento del insulinoma relacionado con el MEN1. MÉTODOS: Se identificaron los pacientes con insulinomas relacionados con el MEN1 en 46 centros de Europa y América del Norte entre 1990 y 2016. Los insulinomas se consideraron localizados si el tumor se localizaba en la cabeza o en el cuerpo/cola del páncreas. Se sospechó la existencia de un insulinoma multifocal en los pacientes con tumores neuroendocrinos pancreáticos (pNETs). El objetivo primario de este estudio fue evaluar la hipoglucemia postoperatoria, definida como hipoglucemia persistente, hipoglucemia recidivante causada por un nuevo insulinoma o debida a metástasis hepáticas productoras de insulina. La supervivencia libre de hipoglucemia se estimó mediante el método de Kaplan-Meier. RESULTADOS: A 96 se les realizó una resección por insulinoma en el contexto del MEN1. Un total de 63 y 33 pacientes presentaron insulinomas localizados y multifocales, respectivamente. Después de una mediana de seguimiento de 7,8 años (rango 1-22), un paciente (1%) tenía enfermedad persistente y seis pacientes (6%) presentaron enfermedad recidivante, de los cuales cuatro desarrollaron un nuevo insulinoma. La supervivencia libre de hipoglucemia fue del 91% a los 10 años (i.c. del 95%, 80%-96%). De los pacientes con enfermedad localizada, 46 fueron sometidos a resección pancreática y 17 pacientes a enucleación. Entre éstos, un paciente tenía enfermedad persistente y uno desarrolló insulinoma recidivante, respectivamente. De los pacientes con enfermedad multifocal, tres desarrollaron nuevos insulinomas y dos desarrollaron metástasis hepáticas productoras de insulina. CONCLUSIÓN: La cirugía para el insulinoma en el contexto del MEN1 es más exitosa de lo que parecía en principio.


Assuntos
Insulinoma/cirurgia , Neoplasia Endócrina Múltipla Tipo 1/cirurgia , Pancreatectomia , Neoplasias Pancreáticas/cirurgia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Tomada de Decisão Clínica , Feminino , Seguimentos , Humanos , Hipoglicemia/epidemiologia , Hipoglicemia/etiologia , Insulinoma/complicações , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Neoplasia Endócrina Múltipla Tipo 1/complicações , Recidiva Local de Neoplasia/epidemiologia , Neoplasias Pancreáticas/complicações , Complicações Pós-Operatórias/epidemiologia , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
3.
Sci Rep ; 10(1): 4746, 2020 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-32179788

RESUMO

Ginkgolic acids (GA) are alkylphenol constituents of the leaves and fruits of Ginkgo biloba. GA has shown pleiotropic effects in vitro, including: antitumor effects through inhibition of lipogenesis; decreased expression of invasion associated proteins through AMPK activation; and potential rescue of amyloid-ß (Aß) induced synaptic impairment. GA was also reported to have activity against Escherichia coli and Staphylococcus aureus. Several mechanisms for this activity have been suggested including: SUMOylation inhibition; blocking formation of the E1-SUMO intermediate; inhibition of fatty acid synthase; non-specific SIRT inhibition; and activation of protein phosphatase type-2C. Here we report that GA inhibits Herpes simplex virus type 1 (HSV-1) by inhibition of both fusion and viral protein synthesis. Additionally, we report that GA inhibits human cytomegalovirus (HCMV) genome replication and Zika virus (ZIKV) infection of normal human astrocytes (NHA). We show a broad spectrum of fusion inhibition by GA of all three classes of fusion proteins including HIV, Ebola virus (EBOV), influenza A virus (IAV) and Epstein Barr virus (EBV). In addition, we show inhibition of a non-enveloped adenovirus. Our experiments suggest that GA inhibits virion entry by blocking the initial fusion event. Data showing inhibition of HSV-1 and CMV replication, when GA is administered post-infection, suggest a possible secondary mechanism targeting protein and DNA synthesis. Thus, in light of the strong effect of GA on viral infection, even after the infection begins, it may potentially be used to treat acute infections (e.g. Coronavirus, EBOV, ZIKV, IAV and measles), and also topically for the successful treatment of active lesions (e.g. HSV-1, HSV-2 and varicella-zoster virus (VZV)).


Assuntos
Antivirais/farmacologia , Infecções por Vírus de DNA/metabolismo , Vírus de DNA/efeitos dos fármacos , Infecções por Vírus de RNA/metabolismo , Vírus de RNA/efeitos dos fármacos , Salicilatos/farmacologia , Proteínas do Envelope Viral/antagonistas & inibidores , Proteínas Virais de Fusão/antagonistas & inibidores , Animais , Astrócitos/metabolismo , Chlorocebus aethiops , Replicação do DNA/efeitos dos fármacos , Infecções por Vírus de DNA/virologia , Vírus de DNA/genética , DNA Viral/genética , Células HEK293 , Humanos , Infecções por Vírus de RNA/virologia , Vírus de RNA/genética , Células Vero , Proteínas do Envelope Viral/biossíntese , Proteínas Virais de Fusão/biossíntese , Vírion/efeitos dos fármacos , Internalização do Vírus/efeitos dos fármacos , Replicação Viral/efeitos dos fármacos
4.
Pathog Immun ; 4(1): 66-78, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30815626

RESUMO

BACKGROUND: Among HIV-positive individuals, increased levels of inflammation and immune activation persist even in the setting of effective antiretroviral therapy (ART) and are associated with greater rates of non-AIDS events. The etiology of this persistent inflammation is incompletely understood. METHODS: Using a well-characterized cohort of 322 HIV-infected individuals on suppressive ART, we conducted a case-control study. Cytomegalovirus (CMV) immunoglobulin G (IgG) levels, plasma biomarkers, and T-cell phenotypes were measured/characterized from samples collected 1 year after ART initiation. Conditional logistic regression for matched case-control studies analyzed the associations of year 1 CMV-specific IgG level with the subsequent occurrence of any non-AIDS event. Correlations between continuous CMV IgG antibody levels and soluble and cellular markers were assessed. RESULTS: We found that higher levels of CMV IgG were associated with increased risk of non-AIDS events (OR = 1.58 per IQR [95% CI: 1.12, 2.24], P = 0.01) and with elevated soluble and cellular markers of inflammation. CONCLUSIONS: The magnitude of the host immune response to CMV may play a role in the persistent inflammation and resultant morbid events observed in the HIV-positive population.

5.
J Virol ; 90(23): 10715-10727, 2016 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-27654292

RESUMO

Cytomegalovirus (CMV) is a ubiquitous human pathogen that increases the morbidity and mortality of immunocompromised individuals. The current FDA-approved treatments for CMV infection are intended to be virus specific, yet they have significant adverse side effects, including nephrotoxicity and hematological toxicity. Thus, there is a medical need for safer and more effective CMV therapeutics. Using a high-content screen, we identified the cardiac glycoside convallatoxin as an effective compound that inhibits CMV infection. Using a panel of cardiac glycoside variants, we assessed the structural elements critical for anti-CMV activity by both experimental and in silico methods. Analysis of the antiviral effects, toxicities, and pharmacodynamics of different variants of cardiac glycosides identified the mechanism of inhibition as reduction of methionine import, leading to decreased immediate-early gene translation without significant toxicity. Also, convallatoxin was found to dramatically reduce the proliferation of clinical CMV strains, implying that its mechanism of action is an effective strategy to block CMV dissemination. Our study has uncovered the mechanism and structural elements of convallatoxin, which are important for effectively inhibiting CMV infection by targeting the expression of immediate-early genes. IMPORTANCE: Cytomegalovirus is a highly prevalent virus capable of causing severe disease in certain populations. The current FDA-approved therapeutics all target the same stage of the viral life cycle and induce toxicity and viral resistance. We identified convallatoxin, a novel cell-targeting antiviral that inhibits CMV infection by decreasing the synthesis of viral proteins. At doses low enough for cells to tolerate, convallatoxin was able to inhibit primary isolates of CMV, including those resistant to the anti-CMV drug ganciclovir. In addition to identifying convallatoxin as a novel antiviral, limiting mRNA translation has a dramatic impact on CMV infection and proliferation.


Assuntos
Antivirais/farmacologia , Infecções por Citomegalovirus/prevenção & controle , Citomegalovirus/efeitos dos fármacos , Metionina/metabolismo , Estrofantinas/farmacologia , Antivirais/química , Transporte Biológico Ativo/efeitos dos fármacos , Glicosídeos Cardíacos/química , Glicosídeos Cardíacos/farmacologia , Linhagem Celular , Citomegalovirus/genética , Citomegalovirus/fisiologia , Infecções por Citomegalovirus/metabolismo , Infecções por Citomegalovirus/virologia , Genes Precoces/efeitos dos fármacos , Genes Virais/efeitos dos fármacos , Humanos , Testes de Sensibilidade Microbiana , Modelos Moleculares , Estrutura Molecular , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Viral/genética , RNA Viral/metabolismo , Estrofantinas/química , Relação Estrutura-Atividade , Replicação Viral/efeitos dos fármacos
6.
AIDS Res Hum Retroviruses ; 32(2): 134-43, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26422187

RESUMO

Three groups of cytomegalovirus (CMV)-seropositive women (total n = 164) were selected from the Chicago Women's Interagency HIV-1 Study to investigate the association between CMV coinfection and immune activation: (1) HIV-1 viremic, (2) HIV-1 aviremic, and (3) HIV-1 uninfected. Quantitative measures of CMV serum IgG, CMV DNA, and serum biomarkers interleukin (IL)-6, soluble CD163 (sCD163), soluble CD14 (sCD14), and interferon gamma-induced protein (IP10) were obtained. Levels of CMV IgG and the serum biomarkers were significantly higher in the HIV-1 viremic group compared to the aviremic and uninfected groups (p < 0.001). No significant associations with CMV IgG levels were found for HIV-uninfected women. When each of the HIV-infected groups was analyzed, sCD14 levels in the viremic women were significantly associated with CMV IgG levels with p < 0.02 when adjusted for age, CD4 count, and HIV viral load. There was also a modest association (p = 0.036) with IL-6 from plasma and cervical vaginal lavage specimens both unadjusted and adjusted for CD4 count and HIV viral load. The association of CMV IgG level with sCD14 implicates the monocyte as a potential site for interaction of the two viruses, which eventually may lead to non-AIDS-defining pathological conditions.


Assuntos
Coinfecção/imunologia , Infecções por Citomegalovirus/imunologia , Citomegalovirus/imunologia , Infecções por HIV/imunologia , HIV-1/imunologia , Adulto , Fármacos Anti-HIV/uso terapêutico , Anticorpos Antivirais/sangue , Antígenos CD/sangue , Antígenos de Diferenciação Mielomonocítica/sangue , Biomarcadores/sangue , Coinfecção/sangue , Coinfecção/virologia , Infecções por Citomegalovirus/tratamento farmacológico , Infecções por Citomegalovirus/virologia , Feminino , Infecções por HIV/tratamento farmacológico , Infecções por HIV/virologia , Humanos , Imunoglobulina G/sangue , Inflamação/imunologia , Inflamação/virologia , Interferon gama/sangue , Interleucina-6/sangue , Receptores de Lipopolissacarídeos/sangue , Pessoa de Meia-Idade , Raltegravir Potássico/uso terapêutico , Receptores de Superfície Celular/sangue , Carga Viral , Viremia/virologia
7.
Chem Commun (Camb) ; 51(47): 9702-5, 2015 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-25978687

RESUMO

The coordination modes of the [Au(PPh3)](+) cation to metal alkynyl complexes have been investigated. On addition to ruthenium, a vinylidene complex, [Ru(η(5)-C5H5)(PPh3)2([double bond, length as m-dash]C[double bond, length as m-dash]CPh{AuPPh3})](+), is obtained while addition to a gold(iii) compound gives di- and trinuclear gold complexes depending on the conditions employed. In the trinuclear species, a gold(i) cation is sandwiched between two gold(iii) alkynyl complexes, suggesting that coordination of multiple C-C triple bonds to gold is facile.

8.
J Am Chem Soc ; 136(38): 13453-7, 2014 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-25166923

RESUMO

Aromatic hydrogenation is a challenging transformation typically requiring alkali or transition metal reagents and/or harsh conditions to facilitate the process. In sharp contrast, the aromatic heterocycle 2,4,6-tri-tert-butyl-1,3,5-triphosphabenzene is shown to be reduced under 4 atm of H2 to give [3.1.0]bicylo reduction products, with the structure of the major isomer being confirmed by X-ray crystallography. NMR studies show this reaction proceeds via a reversible 1,4-H2 addition to generate an intermediate species, which undergoes an irreversible suprafacial hydride shift concurrent with P-P bond formation to give the isolated products. Further, para-hydrogen experiments confirmed the addition of H2 to triphosphabenzene is a bimolecular process. Density functional theory (DFT) calculations show that facile distortion of the planar triphosphabenzene toward a boat-conformation provides a suprafacial combination of vacant acceptor and donor orbitals that permits this direct and uncatalyzed reduction of the aromatic molecule.


Assuntos
Compostos Bicíclicos com Pontes/química , Hidrogênio/química , Compostos Organofosforados/química , Cristalografia por Raios X , Hidrogenação , Isomerismo , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Oxirredução
10.
J Immunol ; 191(2): 828-36, 2013 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-23761635

RESUMO

Lymphocyte activation is regulated by costimulatory and inhibitory receptors, of which both B and T lymphocyte attenuator (BTLA) and CD160 engage herpesvirus entry mediator (HVEM). Notably, it remains unclear how HVEM functions with each of its ligands during immune responses. In this study, we show that HVEM specifically activates CD160 on effector NK cells challenged with virus-infected cells. Human CD56(dim) NK cells were costimulated specifically by HVEM but not by other receptors that share the HVEM ligands LIGHT, Lymphotoxin-α, or BTLA. HVEM enhanced human NK cell activation by type I IFN and IL-2, resulting in increased IFN-γ and TNF-α secretion, and tumor cell-expressed HVEM activated CD160 in a human NK cell line, causing rapid hyperphosphorylation of serine kinases ERK1/2 and AKT and enhanced cytolysis of target cells. In contrast, HVEM activation of BTLA reduced cytolysis of target cells. Together, our results demonstrate that HVEM functions as a regulator of immune function that activates NK cells via CD160 and limits lymphocyte-induced inflammation via association with BTLA.


Assuntos
Antígenos CD/metabolismo , Células Matadoras Naturais/imunologia , Receptores Imunológicos/metabolismo , Membro 14 de Receptores do Fator de Necrose Tumoral/metabolismo , Antígeno CD56/metabolismo , Linhagem Celular , Ativação Enzimática , Proteínas Ligadas por GPI/metabolismo , Células HEK293 , Humanos , Inflamação , Interferon Tipo I/metabolismo , Interferon gama/metabolismo , Interleucina-2/metabolismo , Células Matadoras Naturais/metabolismo , Ativação Linfocitária , Linfotoxina-alfa/metabolismo , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Fosforilação , Proteínas Proto-Oncogênicas c-akt/metabolismo , Membro 14 de Receptores do Fator de Necrose Tumoral/imunologia , Transdução de Sinais , Linfócitos T/imunologia , Membro 14 da Superfamília de Ligantes de Fatores de Necrose Tumoral/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
11.
J Infect Dis ; 208(4): 564-72, 2013 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-23661800

RESUMO

Serum, cerebrospinal fluid (CSF), and cryopreserved lymphocytes from subjects in the Rush Alzheimer's Disease Center Religious Orders Study were analyzed for associations between cytomegalovirus (CMV) infection and clinical and pathological markers of Alzheimer disease. CMV antibody levels were associated with neurofibrillary tangles (NFTs). CSF interferon γ was only detected in seropositive subjects and was significantly associated with NFTs. The percentage of senescent T cells (CD4+ or CD8+CD28-CD57+) was significantly higher for CMV-seropositive as compared to CMV-seronegative subjects and was marginally associated with the pathologic diagnosis of Alzheimer disease (CD4+) or amyloid-ß (CD8+). Immunocytochemical analysis showed induction of amyloid-ß in human foreskin fibroblasts (HFFs) infected with each of 3 clinical CMV strains. In the same subjects, there was no association of herpes simplex virus type 1 (HSV-1) antibody levels with CMV antibody levels or clinical or pathological markers of Alzheimer disease. HSV-1 infection of HFFs did not induce amyloid-ß. These data support an association between CMV and the development of Alzheimer disease.


Assuntos
Doença de Alzheimer/complicações , Doença de Alzheimer/patologia , Infecções por Citomegalovirus/imunologia , Infecções por Citomegalovirus/virologia , Idoso , Idoso de 80 Anos ou mais , Peptídeos beta-Amiloides/análise , Anticorpos Antivirais/sangue , Anticorpos Antivirais/líquido cefalorraquidiano , Infecções por Citomegalovirus/complicações , Feminino , Fibroblastos/química , Fibroblastos/virologia , Humanos , Interferon gama/líquido cefalorraquidiano , Masculino , Emaranhados Neurofibrilares/metabolismo , Subpopulações de Linfócitos T/imunologia
13.
J Virol ; 85(24): 13204-13, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21976654

RESUMO

Human cytomegalovirus (HCMV) is the leading cause of congenital infection, associated with severe birth defects and intrauterine growth retardation. The mechanism of HCMV transmission via the maternal-fetal interface is largely unknown, and there are no animal models for HCMV. The initial stages of infection are believed to occur in the maternal decidua. Here we employed a novel decidual organ culture, using both clinically derived and laboratory-derived viral strains, for the ex vivo modeling of HCMV transmission in the maternal-fetal interface. Viral spread in the tissue was demonstrated by the progression of infected-cell foci, with a 1.3- to 2-log increase in HCMV DNA and RNA levels between days 2 and 9 postinfection, the expression of immediate-early and late proteins, the appearance of typical histopathological features of natural infection, and dose-dependent inhibition of infection by ganciclovir and acyclovir. HCMV infected a wide range of cells in the decidua, including invasive cytotrophoblasts, macrophages, and endothelial, decidual, and dendritic cells. Cell-to-cell viral spread was revealed by focal extension of infected-cell clusters, inability to recover infectious extracellular virus, and high relative proportions (88 to 93%) of cell-associated viral DNA. Intriguingly, neutralizing HCMV hyperimmune globulins exhibited inhibitory activity against viral spread in the decidua even when added at 24 h postinfection-providing a mechanistic basis for their clinical use in prenatal prevention. The ex vivo-infected decidual cultures offer unique insight into patterns of viral tropism and spread, defining initial stages of congenital HCMV transmission, and can facilitate evaluation of the effects of new antiviral interventions within the maternal-fetal interface milieu.


Assuntos
Infecções por Citomegalovirus/transmissão , Decídua/virologia , Transmissão Vertical de Doenças Infecciosas , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , DNA Viral/genética , DNA Viral/isolamento & purificação , Feminino , Expressão Gênica , Humanos , Modelos Biológicos , Técnicas de Cultura de Órgãos/métodos , Gravidez , RNA Viral/genética , RNA Viral/isolamento & purificação , Fatores de Tempo , Proteínas Virais/biossíntese
14.
J Clin Microbiol ; 49(8): 2854-8, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21697326

RESUMO

The performance characteristics of four different assays for hepatitis B virus (HBV) quantification were assessed: the Abbott RealTime HBV IUO, the Roche Cobas AmpliPrep/Cobas TaqMan HBV test, the Roche Cobas TaqMan HBV test with HighPure system, and the Qiagen artus HBV TM ASR. Limit of detection (LOD), linear range, reproducibility, and agreement were determined using a serially diluted plasma sample from a single chronically infected subject. Each assay was tested by at least three laboratories. The LOD of the RealTime and two TaqMan assays was approximately 1.0 log(10) IU/ml; for artus HBV (which used the lowest volume of extracted DNA), it was approximately 1.5 log(10) IU/ml. The linear range spanned 1.0 to at least 7.0 log(10) IU/ml for all assays. Median values were consistently lowest for artus HBV and highest for Cobas AmpliPrep/Cobas TaqMan HBV. Assays incorporating automated nucleic acid extraction were the most reproducible; however, the overall variability was minor since the standard deviations for the means of all tested concentrations were ≤0.32 log(10) IU/ml for all assays. False-positive results were observed with all assays; the highest rates occurred with tests using manual nucleic acid extraction. The performance characteristics of these assays suggest that they are useful for management and therapeutic monitoring of chronic HBV infection.


Assuntos
DNA Viral/isolamento & purificação , Vírus da Hepatite B/isolamento & purificação , Hepatite B/virologia , Reação em Cadeia da Polimerase em Tempo Real/métodos , Carga Viral/métodos , DNA Viral/genética , Vírus da Hepatite B/genética , Humanos , Plasma/virologia , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
15.
Clin Microbiol Rev ; 23(4): 689-712, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20930070

RESUMO

The study of human cytomegalovirus (HCMV) antiviral drug resistance has enhanced knowledge of the virological targets and the mechanisms of antiviral activity. The currently approved drugs, ganciclovir (GCV), foscarnet (FOS), and cidofovir (CDV), target the viral DNA polymerase. GCV anabolism also requires phosphorylation by the virus-encoded UL97 kinase. GCV resistance mutations have been identified in both genes, while FOS and CDV mutations occur only in the DNA polymerase gene. Confirmation of resistance mutations requires phenotypic analysis; however, phenotypic assays are too time-consuming for diagnostic purposes. Genotypic assays based on sequencing provide more rapid results but are dependent on prior validation by phenotypic methods. Reports from many laboratories have produced an evolving list of confirmed resistance mutations, although differences in interpretation have led to some confusion. Recombinant phenotyping methods performed in a few research laboratories have resolved some of the conflicting results. Treatment options for drug-resistant HCMV infections are complex and have not been subjected to controlled clinical trials, although consensus guidelines have been proposed. This review summarizes the virological and clinical data pertaining to HCMV antiviral drug resistance.


Assuntos
Antivirais/farmacologia , Citomegalovirus/efeitos dos fármacos , Farmacorresistência Viral/genética , Antivirais/uso terapêutico , Cidofovir , Citomegalovirus/genética , Infecções por Citomegalovirus/tratamento farmacológico , Citosina/análogos & derivados , Citosina/farmacologia , Citosina/uso terapêutico , DNA Polimerase Dirigida por DNA , Foscarnet/farmacologia , Foscarnet/uso terapêutico , Ganciclovir/farmacologia , Ganciclovir/uso terapêutico , Genoma Viral , Humanos , Organofosfonatos/farmacologia , Organofosfonatos/uso terapêutico , Fosfotransferases (Aceptor do Grupo Álcool)/genética , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Análise de Sequência de DNA
16.
Chemistry ; 16(28): 8376-89, 2010 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-20572181

RESUMO

Oxidative addition of aryl bromides to 12-electron [Rh(PiBu(3))(2)][BAr(F)(4)] (Ar(F)=3,5-(CF(3))(2)C(6)H(3)) forms a variety of products. With p-tolyl bromides, Rh(III) dimeric complexes result [Rh(PiBu(3))(2)(o/p-MeC(6)H(4))(mu-Br)](2)[BAr(F)(4)](2). Similarly, reaction with p-ClC(6)H(4)Br gives [Rh(PiBu(3))(2)(p-ClC(6)H(4))(mu-Br)](2)[BAr(F)(4)](2). In contrast, the use of o-BrC(6)H(4)Me leads to a product in which toluene has been eliminated and an isobutyl phosphine has undergone C-H activation: [Rh{PiBu(2)(CH(2)CHCH(3)CH(2))}(PiBu(3))(mu-Br)](2)[BAr(F)(4)](2). Trapping experiments with ortho-bromo anisole or ortho-bromo thioanisole indicate that a possible intermediate for this process is a low-coordinate Rh(III) complex that then undergoes C-H activation. The anisole and thioanisole complexes have been isolated and their structures show OMe or SMe interactions with the metal centre alongside supporting agostic interactions, [Rh(PiBu(3))(2)(C(6)H(4)OMe)Br][BAr(F)(4)] (the solid-state structure of the 5-methyl substituted analogue is reported) and [Rh(PiBu(3))(2)(C(6)H(4)SMe)Br][BAr(F)(4)]. The anisole-derived complex proceeds to give [Rh{PiBu(2)(CH(2)CHCH(3)CH(2))}(PiBu(3))(mu-Br)](2)[BAr(F)(4)](2), whereas the thioanisole complex is unreactive. The isolation of [Rh(PiBu(3))(2)(C(6)H(4)OMe)Br][BAr(F)(4)] and its onward reactivity to give the products of C-H activation and aryl elimination suggest that it is implicated on the pathway of a sigma-bond metathesis reaction, a hypothesis strengthened by DFT calculations. Calculations also suggest that C-H bond cleavage through phosphine-assisted deprotonation of a non-agostic bond is also competitive, although the subsequent protonation of the aryl ligand is too high in energy to account for product formation. C-H activation through oxidative addition is also ruled out on the basis of these calculations. These new complexes have been characterised by solution NMR/ESIMS techniques and in the solid-state by X-ray crystallography.

17.
J Clin Microbiol ; 47(11): 3530-9, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19726602

RESUMO

Microbicide candidates with promising in vitro activity are often advanced for evaluations using human primary tissue explants relevant to the in vivo mucosal transmission of human immunodeficiency virus type 1 (HIV-1), such as tonsil, cervical, or rectal tissue. To compare virus growth or the anti-HIV-1 efficacies of candidate microbicides in tissue explants, a novel soft-endpoint method was evaluated to provide a single, objective measurement of virus growth. The applicability of the soft endpoint is shown across several different ex vivo tissue types, with the method performed in different laboratories, and for a candidate microbicide (PRO 2000). The soft-endpoint method was compared to several other endpoint methods, including (i) the growth of virus on specific days after infection, (ii) the area under the virus growth curve, and (iii) the slope of the virus growth curve. Virus growth at the assay soft endpoint was compared between laboratories, methods, and experimental conditions, using nonparametric statistical analyses. Intra-assay variability determinations using the coefficient of variation demonstrated higher variability for virus growth in rectal explants. Significant virus inhibition by PRO 2000 and significant differences in the growth of certain primary HIV-1 isolates were observed by the majority of laboratories. These studies indicate that different laboratories can provide consistent measurements of anti-HIV-1 microbicide efficacy when (i) the soft endpoint or another standardized endpoint is used, (ii) drugs and/or virus reagents are centrally sourced, and (iii) the same explant tissue type and method are used. Application of the soft-endpoint method reduces the inherent variability in comparisons of preclinical assays used for microbicide development.


Assuntos
Anti-Infecciosos/farmacologia , HIV-1/efeitos dos fármacos , Testes de Sensibilidade Microbiana/métodos , Testes de Sensibilidade Microbiana/normas , Colo do Útero/virologia , Feminino , Humanos , Técnicas In Vitro , Masculino , Mucosa/virologia , Tonsila Palatina/virologia , Reto/virologia , Reprodutibilidade dos Testes , Replicação Viral/efeitos dos fármacos
18.
J Gen Virol ; 90(Pt 10): 2375-2380, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19553388

RESUMO

The genomes of commonly used variants of human cytomegalovirus (HCMV) strains Towne and AD169 each contain a substantial mutation in which a region (U(L)/b') at the right end of the long unique region has been replaced by an inverted duplication of a region from the left end of the genome. Using high-throughput technology, we have sequenced HCMV strain Towne (ATCC VR-977) and confirmed the presence of two variants, one exhibiting the replacement in U(L)/b' and the other intact in this region. Both variants are mutated in genes RL13, UL1, UL40, UL130, US1 and US9. We have also sequenced a novel AD169 variant (varUC) that is intact in U(L)/b' except for a small deletion that affects genes UL144, UL142, UL141 and UL140. Like other AD169 variants, varUC is mutated in genes RL5A, RL13, UL36 and UL131A. A subpopulation of varUC contains an additional deletion affecting genes IRS1, US1 and US2.


Assuntos
Citomegalovirus/classificação , Citomegalovirus/genética , Variação Genética , Sequência de Bases , DNA Viral , Genoma Viral , Humanos , Mutação
19.
Clin Infect Dis ; 46(9): 1455-7, 2008 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-18419454

RESUMO

This is the first report of treatment of cytomegalovirus infection with artesunate, for a stem cell transplant recipient with a newly identified foscarnet-resistant and ganciclovir-resistant DNA polymerase L776M mutation. Artesunate treatment resulted in a 1.7-2.1-log reduction in viral load by treatment day 7, with a viral half-life of 0.9-1.9 days, indicating a highly effective block in viral replication.


Assuntos
Artemisininas/uso terapêutico , Infecções por Citomegalovirus/tratamento farmacológico , Transplante de Células-Tronco Hematopoéticas/métodos , Antivirais/farmacologia , Antivirais/uso terapêutico , Artemisininas/farmacologia , Artesunato , Criança , Citomegalovirus/efeitos dos fármacos , Infecções por Citomegalovirus/etiologia , Farmacorresistência Viral , Foscarnet/farmacologia , Foscarnet/uso terapêutico , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Humanos , Masculino , Resultado do Tratamento
20.
AIDS Res Hum Retroviruses ; 24(3): 453-62, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18327985

RESUMO

HIV-1 copathogens are believed to play a critical role in progression to AIDS. Human cytomegalovirus (HCMV) has a high prevalence in the general population and is a common copathogen in HIV-1-infected individuals. Important events in copathogen interactions with HIV-1 take place in lymphoid tissue where critical events in HIV-1 disease occur. Here, we used an experimental system of human lymphoid tissue ex vivo to investigate interactions of HCMV with HIV-1. We inoculated ex vivo blocks of human lymphoid tissue with a recombinant strain of HCMV, expressing the green fluorescent protein, and HIV-1 and monitored viral replication and the phenotype of productively infected cells. HCMV readily replicated in tissue blocks as revealed by the release of HCMV viral DNA and an increasing number of viral-positive cells. Immunophenotyping of HCMV-infected cells showed a preferential infection of activated lymphocytes. The number of these cells significantly increased in HIV-1-coinfected tissues. Accordingly, HCMV replication was enhanced 2- to-3 fold. This upregulation occurred in tissues infected with either CXCR4- or CCR5-utilizing HIV-1. Thus, HIV-1 creates new targets for HCMV, which may explain the strong association of HCMV with HIV-1 infection in vivo. Ex vivo-infected human lymphoid tissue constitutes a model to study the mechanisms of HCMV tissue pathogenesis and its interactions with HIV-1 and this model may provide new targets for anti-HIV-1 therapy.


Assuntos
Citomegalovirus/crescimento & desenvolvimento , HIV-1/crescimento & desenvolvimento , Tecido Linfoide/virologia , Replicação Viral , Citomegalovirus/genética , DNA Viral/metabolismo , Genes Reporter , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Humanos , Linfócitos/virologia , Técnicas de Cultura de Órgãos
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