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1.
Chempluschem ; : e202400083, 2024 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-38523404

RESUMO

We report the synthesis of core-shell Ni-Pt nanoparticles (NPs) with varying degrees of crystallographic facets and surface layers rich in Pt via a seed-mediated thermolytic approach. Mixtures of different surfactants used during synthesis resulted in preferential surface passivation, which in turn dictated the size, chemical composition, and geometric evolution of these PtNi NPs. Electrochemical investigations of these pristine core-shell Ni-Pt structures in the oxygen reduction reaction (ORR) show that their catalytic functionalities outperform the commercial Pt/C reference catalyst. The enhanced electrocatalytic ORR performances of these Pt-based PtNi NPs are correlated with the weakened oxygen binding strength or surface-adsorbed hydroxyl (OH) species on active Pt surface sites induced by the downshift of the d-band center as a result of compressive strain effects. Our studies offer a robust synthetic approach for the development of core-shell nanostructures for enhanced ORR catalysis.

2.
Open Forum Infect Dis ; 10(6): ofad290, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37383244

RESUMO

Background: Clinical trials initiated during emerging infectious disease outbreaks must quickly enroll participants to identify treatments to reduce morbidity and mortality. This may be at odds with enrolling a representative study population, especially when the population affected is undefined. Methods: We evaluated the utility of the Centers for Disease Control and Prevention's COVID-19-Associated Hospitalization Surveillance Network (COVID-NET), the COVID-19 Case Surveillance System (CCSS), and 2020 United States (US) Census data to determine demographic representation in the 4 stages of the Adaptive COVID-19 Treatment Trial (ACTT). We compared the cumulative proportion of participants by sex, race, ethnicity, and age enrolled at US ACTT sites, with respective 95% confidence intervals, to the reference data in forest plots. Results: US ACTT sites enrolled 3509 adults hospitalized with COVID-19. When compared with COVID-NET, ACTT enrolled a similar or higher proportion of Hispanic/Latino and White participants depending on the stage, and a similar proportion of African American participants in all stages. In contrast, ACTT enrolled a higher proportion of these groups when compared with US Census and CCSS. The proportion of participants aged ≥65 years was either similar or lower than COVID-NET and higher than CCSS and the US Census. The proportion of females enrolled in ACTT was lower than the proportion of females in the reference datasets. Conclusions: Although surveillance data of hospitalized cases may not be available early in an outbreak, they are a better comparator than US Census data and surveillance of all cases, which may not reflect the population affected and at higher risk of severe disease.

3.
Open Forum Infect Dis ; 10(5): ofad205, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37206623

RESUMO

We performed a secondary analysis of the National Institutes of Health-sponsored Adaptive COVID-19 Treatment Trial (ACTT-2) randomized controlled trial and found that baricitinib was associated with a 50% reduction in secondary infections after controlling for baseline and postrandomization patient characteristics. This finding provides a novel mechanism of benefit for baricitinib and supports the safety profile of this immunomodulator for the treatment of coronavirus disease 2019.

4.
Ann Intern Med ; 175(12): 1716-1727, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36442063

RESUMO

BACKGROUND: The COVID-19 standard of care (SOC) evolved rapidly during 2020 and 2021, but its cumulative effect over time is unclear. OBJECTIVE: To evaluate whether recovery and mortality improved as SOC evolved, using data from ACTT (Adaptive COVID-19 Treatment Trial). DESIGN: ACTT is a series of phase 3, randomized, double-blind, placebo-controlled trials that evaluated COVID-19 therapeutics from February 2020 through May 2021. ACTT-1 compared remdesivir plus SOC to placebo plus SOC, and in ACTT-2 and ACTT-3, remdesivir plus SOC was the control group. This post hoc analysis compared recovery and mortality between these comparable sequential cohorts of patients who received remdesivir plus SOC, adjusting for baseline characteristics with propensity score weighting. The analysis was repeated for participants in ACTT-3 and ACTT-4 who received remdesivir plus dexamethasone plus SOC. Trends in SOC that could explain outcome improvements were analyzed. (ClinicalTrials.gov: NCT04280705 [ACTT-1], NCT04401579 [ACTT-2], NCT04492475 [ACTT-3], and NCT04640168 [ACTT-4]). SETTING: 94 hospitals in 10 countries (86% U.S. participants). PARTICIPANTS: Adults hospitalized with COVID-19. INTERVENTION: SOC. MEASUREMENTS: 28-day mortality and recovery. RESULTS: Although outcomes were better in ACTT-2 than in ACTT-1, adjusted hazard ratios (HRs) were close to 1 (HR for recovery, 1.04 [95% CI, 0.92 to 1.17]; HR for mortality, 0.90 [CI, 0.56 to 1.40]). Comparable patients were less likely to be intubated in ACTT-2 than in ACTT-1 (odds ratio, 0.75 [CI, 0.53 to 0.97]), and hydroxychloroquine use decreased. Outcomes improved from ACTT-2 to ACTT-3 (HR for recovery, 1.43 [CI, 1.24 to 1.64]; HR for mortality, 0.45 [CI, 0.21 to 0.97]). Potential explanatory factors (SOC trends, case surges, and variant trends) were similar between ACTT-2 and ACTT-3, except for increased dexamethasone use (11% to 77%). Outcomes were similar in ACTT-3 and ACTT-4. Antibiotic use decreased gradually across all stages. LIMITATION: Unmeasured confounding. CONCLUSION: Changes in patient composition explained improved outcomes from ACTT-1 to ACTT-2 but not from ACTT-2 to ACTT-3, suggesting improved SOC. These results support excluding nonconcurrent controls from analysis of platform trials in rapidly changing therapeutic areas. PRIMARY FUNDING SOURCE: National Institute of Allergy and Infectious Diseases.


Assuntos
Antivirais , Tratamento Farmacológico da COVID-19 , Adulto , Humanos , Antivirais/uso terapêutico , Ensaios Clínicos Fase III como Assunto , Dexametasona , Método Duplo-Cego , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento
5.
J Leukoc Biol ; 110(6): 1225-1239, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34730254

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the causative agent of coronavirus disease-2019 (COVID-19), a respiratory disease that varies in severity from mild to severe/fatal. Several risk factors for severe disease have been identified, notably age, male sex, and pre-existing conditions such as diabetes, obesity, and hypertension. Several advancements in clinical care have been achieved over the past year, including the use of corticosteroids (e.g., corticosteroids) and other immune-modulatory treatments that have now become standard of care for patients with acute severe COVID-19. While the understanding of the mechanisms that underlie increased disease severity with age has improved over the past few months, it remains incomplete. Furthermore, the molecular impact of corticosteroid treatment on host response to acute SARS-CoV-2 infection has not been investigated. In this study, a cross-sectional and longitudinal analysis of Ab, soluble immune mediators, and transcriptional responses in young (65 ≤ years) and aged (≥ 65 years) diabetic males with obesity hospitalized with acute severe COVID-19 was conducted. Additionally, the transcriptional profiles in samples obtained before and after corticosteroids became standard of care were compared. The analysis indicates that severe COVID-19 is characterized by robust Ab responses, heightened systemic inflammation, increased expression of genes related to inflammatory and pro-apoptotic processes, and reduced expression of those important for adaptive immunity regardless of age. In contrast, COVID-19 patients receiving steroids did not show high levels of systemic immune mediators and lacked transcriptional indicators of heightened inflammatory and apoptotic responses. Overall, these data suggest that inflammation and cell death are key drivers of severe COVID-19 pathogenesis in the absence of corticosteroid therapy.


Assuntos
Corticosteroides/uso terapêutico , Tratamento Farmacológico da COVID-19 , COVID-19/imunologia , Inflamação/imunologia , Transcriptoma/efeitos dos fármacos , Adulto , Idoso , Estudos Transversais , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , SARS-CoV-2 , Transcriptoma/imunologia
6.
Antiviral Res ; 195: 105179, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34530009

RESUMO

Orthopoxviruses such as variola and monkeypox viruses continue to threaten the human population. Monkeypox virus is endemic in central and western Africa and outbreaks have reached as far as the U.S. Although variola virus, the etiologic agent of smallpox, has been eradicated by a successful vaccination program, official and likely clandestine stocks of the virus exist. Moreover, studies with ectromelia virus (the etiological agent of mousepox) have revealed that IL-4 recombinant viruses are significantly more virulent than wild-type viruses even in mice treated with vaccines and/or antivirals. For these reasons, it is critical that antiviral modalities are developed to treat these viruses should outbreaks, or deliberate dissemination, occur. Currently, 2 antivirals (brincidofovir and tecovirimat) are in the U.S. stockpile allowing for emergency use of the drugs to treat smallpox. Both antivirals have advantages and disadvantages in a clinical and emergency setting. Here we report on the efficacy of a recombinant immunoglobulin (rVIG) that demonstrated efficacy against several orthopoxviruses in vitro and in vivo in both a prophylactic and therapeutic fashion. A single intraperitoneal injection of rVIG significantly protected mice when given up to 14 days before or as late as 6 days post challenge. Moreover, rVIG reduced morbidity, as measured by weight-change, as well as several previously established biomarkers of disease. In rVIG treated mice, we found that vDNA levels in blood were significantly reduced, as was ALT (a marker of liver damage) and infectious virus levels in the liver. No apparent adverse events were observed in rVIG treated mice, suggesting the immunoglobulin is well tolerated. These findings suggest that recombinant immunoglobulins could be candidates for further evaluation and possible licensure under the FDA Animal Rule.


Assuntos
Antivirais/uso terapêutico , Imunoglobulinas/uso terapêutico , Orthopoxvirus/efeitos dos fármacos , Varíola/tratamento farmacológico , Vacínia/tratamento farmacológico , Animais , Antivirais/administração & dosagem , Benzamidas , Linhagem Celular , Chlorocebus aethiops , Citosina/análogos & derivados , Feminino , Humanos , Isoindóis , Camundongos , Camundongos Endogâmicos BALB C , Organofosfonatos , Varíola/prevenção & controle , Varíola/virologia , Vacina Antivariólica/administração & dosagem , Vacinas de DNA/administração & dosagem , Vacínia/prevenção & controle , Vacínia/virologia
7.
Crit Care Explor ; 3(7): e0474, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34278310

RESUMO

We sought to validate prognostic scores in coronavirus disease 2019 including National Early Warning Score, Modified Early Warning Score, and age-based modifications, and define their performance characteristics. DESIGN: We analyzed prospectively collected data from the Adaptive COVID-19 Treatment Trial. National Early Warning Score was collected daily during the trial, Modified Early Warning Score was calculated, and age applied to both scores. We assessed prognostic value for the end points of recovery, mechanical ventilation, and death for score at enrollment, average, and slope of score over the first 48 hours. SETTING: A multisite international inpatient trial. PATIENTS: A total of 1,062 adult nonpregnant inpatients with severe coronavirus disease 2019 pneumonia. INTERVENTIONS: Adaptive COVID-19 Treatment Trial 1 randomized participants to receive remdesivir or placebo. The prognostic value of predictive scores was evaluated in both groups separately to assess for differential performance in the setting of remdesivir treatment. MEASUREMENTS AND MAIN RESULTS: For mortality, baseline National Early Warning Score and Modified Early Warning Score were weakly to moderately prognostic (c-index, 0.60-0.68), and improved with addition of age (c-index, 0.66-0.74). For recovery, baseline National Early Warning Score and Modified Early Warning Score demonstrated somewhat better prognostic ability (c-index, 0.65-0.69); however, National Early Warning Score+age and Modified Early Warning Score+age further improved performance (c-index, 0.68-0.71). For deterioration, baseline National Early Warning Score and Modified Early Warning Score were weakly to moderately prognostic (c-index, 0.59-0.69) and improved with addition of age (c-index, 0.63-0.70). All prognostic performance improvements due to addition of age were significant (p < 0.05). CONCLUSIONS: In the Adaptive COVID-19 Treatment Trial 1 cohort, National Early Warning Score and Modified Early Warning Score demonstrated moderate prognostic performance in patients with severe coronavirus disease 2019, with improvement in predictive ability for National Early Warning Score+age and Modified Early Warning Score+age. Area under receiver operating curve for National Early Warning Score and Modified Early Warning Score improved in patients receiving remdesivir versus placebo early in the pandemic for recovery and mortality. Although these scores are simple and readily obtainable in myriad settings, in our data set, they were insufficiently predictive to completely replace clinical judgment in coronavirus disease 2019 and may serve best as an adjunct to triage, disposition, and resourcing decisions.

8.
Cancer Immunol Res ; 9(2): 214-226, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33303575

RESUMO

Antitumor immunity is impaired in obese mice. Mechanistic insight into this observation remains sparse and whether it is recapitulated in patients with cancer is unclear because clinical studies have produced conflicting and controversial findings. We addressed this by analyzing data from patients with a diverse array of cancer types. We found that survival after immunotherapy was not accurately predicted by body mass index or serum leptin concentrations. However, oxidized low-density lipoprotein (ox-LDL) in serum was identified as a suppressor of T-cell function and a driver of tumor cytoprotection mediated by heme oxygenase-1 (HO-1). Analysis of a human melanoma gene expression database showed a clear association between higher HMOX1 (HO-1) expression and reduced progression-free survival. Our in vivo experiments using mouse models of both melanoma and breast cancer revealed HO-1 as a mechanism of resistance to anti-PD1 immunotherapy but also exposed HO-1 as a vulnerability that could be exploited therapeutically using a small-molecule inhibitor. In conclusion, our clinical data have implicated serum ox-LDL as a mediator of therapeutic resistance in patients with cancer, operating as a double-edged sword that both suppressed T-cell immunity and simultaneously induced HO-1-mediated tumor cell protection. Our studies also highlight the therapeutic potential of targeting HO-1 during immunotherapy, encouraging further translational development of this combination approach.See article by Kuehm et al., p. 227.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos , Heme Oxigenase-1/sangue , Lipoproteínas LDL/sangue , Melanoma/tratamento farmacológico , Obesidade/sangue , Animais , Antineoplásicos Imunológicos/uso terapêutico , Índice de Massa Corporal , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Feminino , Humanos , Imunoterapia , Ipilimumab/uso terapêutico , Estimativa de Kaplan-Meier , Modelos Lineares , Masculino , Melanoma/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Obesidade/complicações , Obesidade/fisiopatologia , Estudos Retrospectivos
9.
Nat Med ; 26(2): 228-235, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32015557

RESUMO

Zika virus (ZIKV) has caused significant disease, with widespread cases of neurological pathology and congenital neurologic defects. Rapid vaccine development has led to a number of candidates capable of eliciting potent ZIKV-neutralizing antibodies (reviewed in refs. 1-3). Despite advances in vaccine development, it remains unclear how ZIKV vaccination affects immune responses in humans with prior flavivirus immunity. Here we show that a single-dose immunization of ZIKV purified inactivated vaccine (ZPIV)4-7 in a dengue virus (DENV)-experienced human elicited potent cross-neutralizing antibodies to both ZIKV and DENV. Using a unique ZIKV virion-based sorting strategy, we isolated and characterized multiple antibodies, including one termed MZ4, which targets a novel site of vulnerability centered on the Envelope (E) domain I/III linker region and protects mice from viremia and viral dissemination following ZIKV or DENV-2 challenge. These data demonstrate that Zika vaccination in a DENV-experienced individual can boost pre-existing flavivirus immunity and elicit protective responses against both ZIKV and DENV. ZPIV vaccination in Puerto Rican individuals with prior flavivirus experience yielded similar cross-neutralizing potency after a single vaccination, highlighting the potential benefit of ZIKV vaccination in flavivirus-endemic areas.


Assuntos
Dengue/imunologia , Doadores de Tecidos , Vacinas Virais/uso terapêutico , Infecção por Zika virus/imunologia , Infecção por Zika virus/prevenção & controle , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Chlorocebus aethiops , Reações Cruzadas , Vírus da Dengue , Mapeamento de Epitopos , Feminino , Flavivirus/metabolismo , Humanos , Imunoglobulina G/química , Concentração Inibidora 50 , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Ligação Proteica , Domínios Proteicos , Vacinação , Vacinas de Produtos Inativados/uso terapêutico , Células Vero , Viremia , Zika virus
10.
Lancet ; 391(10120): 563-571, 2018 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-29217375

RESUMO

BACKGROUND: A safe, effective, and rapidly scalable vaccine against Zika virus infection is needed. We developed a purified formalin-inactivated Zika virus vaccine (ZPIV) candidate that showed protection in mice and non-human primates against viraemia after Zika virus challenge. Here we present the preliminary results in human beings. METHODS: We did three phase 1, placebo-controlled, double-blind trials of ZPIV with aluminium hydroxide adjuvant. In all three studies, healthy adults were randomly assigned by a computer-generated list to receive 5 µg ZPIV or saline placebo, in a ratio of 4:1 at Walter Reed Army Institute of Research, Silver Spring, MD, USA, or of 5:1 at Saint Louis University, Saint Louis, MO, USA, and Beth Israel Deaconess Medical Center, Boston, MA, USA. Vaccinations were given intramuscularly on days 1 and 29. The primary objective was safety and immunogenicity of the ZPIV candidate. We recorded adverse events and Zika virus envelope microneutralisation titres up to day 57. These trials are registered at ClinicalTrials.gov, numbers NCT02963909, NCT02952833, and NCT02937233. FINDINGS: We enrolled 68 participants between Nov 7, 2016, and Jan 25, 2017. One was excluded and 67 participants received two injections of Zika vaccine (n=55) or placebo (n=12). The vaccine caused only mild to moderate adverse events. The most frequent local effects were pain (n=40 [60%]) or tenderness (n=32 [47%]) at the injection site, and the most frequent systemic reactogenic events were fatigue (29 [43%]), headache (26 [39%]), and malaise (15 [22%]). By day 57, 52 (92%) of vaccine recipients had seroconverted (microneutralisation titre ≥1:10), with peak geometric mean titres seen at day 43 and exceeding protective thresholds seen in animal studies. INTERPRETATION: The ZPIV candidate was well tolerated and elicited robust neutralising antibody titres in healthy adults. FUNDING: Departments of the Army and Defense and National Institute of Allergy and Infectious Diseases.


Assuntos
Anticorpos Neutralizantes/biossíntese , Anticorpos Antivirais/biossíntese , Vacinas Virais/administração & dosagem , Vacinas Virais/imunologia , Zika virus/imunologia , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Método Duplo-Cego , Humanos
11.
Vaccine ; 33(50): 7126-34, 2015 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-26458804

RESUMO

This review focuses on a dengue virus (DENV) vaccine candidate based on a recombinant subunit approach which targets the DENV envelope glycoprotein (E). Truncated versions of E consisting of the N-terminal portion of E (DEN-80E) have been expressed recombinantly in the Drosophila S2 expression system and shown to have native-like conformation. Preclinical studies demonstrate that formulations containing tetravalent DEN-80E adjuvanted with ISCOMATRIX™ adjuvant induce high titer virus neutralizing antibodies and IFN-γ producing T cells in flavivirus-naïve non-human primates. The preclinical data further suggest that administration of such formulations on a 0, 1, 6 month schedule may result in higher maximum virus neutralizing antibody titers and better durability of those titers compared to administration on a 0, 1, 2 month schedule. In addition, the virus neutralizing antibody titers induced by adjuvanted tetravalent DEN-80E compare favorably to the titers induced by a tetravalent live virus comparator. Furthermore, DEN-80E was demonstrated to be able to boost virus neutralizing antibody titers in macaques that have had a prior DENV exposure. A monovalent version of the vaccine candidate, DEN1-80E, was formulated with Alhydrogel™ and studied in a proof-of-principle Phase I clinical trial by Hawaii Biotech, Inc. (NCT00936429). The clinical trial results demonstrate that both the 10 µg and 50 µg formulations of DEN1-80E with 1.25 mg of elemental aluminum were immunogenic when administered in a 3-injection series (0, 1, 2 months) to healthy, flavivirus-naïve adults. The vaccine formulations induced DENV-1 neutralizing antibodies in the majority of subjects, although the titers in most subjects were modest and waned over time. Both the 10 µg DEN1-80E and the 50 µg DEN1-80E formulations with Alhydrogel™ were generally well tolerated.


Assuntos
Ensaios Clínicos Fase I como Assunto , Vacinas contra Dengue/administração & dosagem , Vacinas contra Dengue/imunologia , Dengue/prevenção & controle , Avaliação Pré-Clínica de Medicamentos , Adjuvantes Imunológicos/administração & dosagem , Hidróxido de Alumínio/administração & dosagem , Animais , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Colesterol/administração & dosagem , Dengue/epidemiologia , Vacinas contra Dengue/genética , Vacinas contra Dengue/isolamento & purificação , Combinação de Medicamentos , Humanos , Esquemas de Imunização , Interferon gama/metabolismo , Macaca , Fosfolipídeos/administração & dosagem , Saponinas/administração & dosagem , Linfócitos T/imunologia , Vacinas de Subunidades Antigênicas/administração & dosagem , Vacinas de Subunidades Antigênicas/genética , Vacinas de Subunidades Antigênicas/imunologia , Vacinas de Subunidades Antigênicas/isolamento & purificação , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/genética , Vacinas Sintéticas/imunologia , Vacinas Sintéticas/isolamento & purificação
12.
J Infect Dis ; 212(10): 1618-28, 2015 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-25943203

RESUMO

We are developing a live-attenuated tetravalent dengue vaccine (TDV) candidate based on an attenuated dengue 2 virus (TDV-2) and 3 chimeric viruses containing the premembrane and envelope genes of dengue viruses (DENVs) -1, -3, and -4 expressed in the context of the attenuated TDV-2 genome (TDV-1, TDV-3, and TDV-4, respectively). In this study, we analyzed and characterized the CD8(+) T-cell response in flavivirus-naive human volunteers vaccinated with 2 doses of TDV 90 days apart via the subcutaneous or intradermal routes. Using peptide arrays and intracellular cytokine staining, we demonstrated that TDV elicits CD8(+) T cells targeting the nonstructural NS1, NS3, and NS5 proteins of TDV-2. The cells were characterized by the production of interferon-γ, tumor necrosis factor-α, and to a lesser extent interleukin-2. Responses were highest on day 90 after the first dose and were still detectable on 180 days after the second dose. In addition, CD8(+) T cells were multifunctional, producing ≥2 cytokines simultaneously, and cross-reactive to NS proteins of the other 3 DENV serotypes. Overall, these findings describe the capacity of our candidate dengue vaccine to elicit cellular immune responses and support the further evaluation of T-cell responses in samples from future TDV clinical trials.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Vacinas contra Dengue/administração & dosagem , Vacinas contra Dengue/imunologia , Vírus da Dengue/imunologia , Adulto , Antígenos Virais/imunologia , Estudos de Coortes , Citocinas/biossíntese , Voluntários Saudáveis , Humanos , Vacinação/métodos , Vacinas Atenuadas/administração & dosagem , Vacinas Atenuadas/imunologia , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/imunologia
13.
J Infect Dis ; 212(7): 1032-41, 2015 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-25791116

RESUMO

BACKGROUND: Dengue viruses (DENVs) infect >300 million people annually, causing 96 million cases of dengue disease and 22 000 deaths [1]. A safe vaccine that protects against DENV disease is a global health priority [2]. METHODS: We enrolled 72 flavivirus-naive healthy adults in a phase 1 double-blinded, randomized, placebo-controlled dose-escalation trial (low and high dose) of a live attenuated recombinant tetravalent dengue vaccine candidate (TDV) given in 2 doses 90 days apart. Volunteers were followed for safety, vaccine component viremia, and development of neutralizing antibodies to the 4 DENV serotypes. RESULTS: The majority of adverse events were mild, with no vaccine-related serious adverse events. Vaccinees reported injection site pain (52% vs 17%) and erythema (73% vs 25%) more frequently than placebo recipients. Low levels of TDV-serotype 2 (TDV-2), TDV-3, and TDV-4 viremia were observed after the first but not second administration of vaccine. Overall seroconversion rates and geometric mean neutralization titers after 2 doses were 84.2% and 54.1, respectively, for DENV serotype 1 (DENV-1); 92.1% and 292.8, respectively, for DENV-2; 86.8% and 32.3, respectively, for DENV-3; and 71.1% and 15.0, respectively, for DENV-4. More than 90.0% of high-dose recipients had trivalent or broader responses. CONCLUSIONS: TDV was generally well tolerated, induced trivalent or broader neutralizing antibodies to DENV in most flavivirus-naive vaccinees, and is undergoing further development. CLINICAL TRIALS REGISTRATION: NCT01110551.


Assuntos
Vacinas contra Dengue/imunologia , Vírus da Dengue/imunologia , Dengue/prevenção & controle , Vacinação , Adolescente , Adulto , Anticorpos Neutralizantes/imunologia , Dengue/imunologia , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Segurança , Vacinas Atenuadas/imunologia , Viremia , Adulto Jovem
14.
Emerg Infect Dis ; 20(11): 1876-9, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25341024

RESUMO

Buruli ulcer, the third most common mycobacterial disease worldwide, rarely affects travelers and is uncommon in the United States. We report a travel-associated case imported from Australia and review 3 previous cases diagnosed and treated in the United States. The differential diagnoses for unusual chronic cutaneous ulcers and those nonresponsive to conventional therapy should include Mycobacterium ulcerans infection.


Assuntos
Úlcera de Buruli/transmissão , Mycobacterium ulcerans/isolamento & purificação , Adulto , Austrália , Úlcera de Buruli/diagnóstico , Úlcera de Buruli/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Missouri , Viagem , Resultado do Tratamento , Adulto Jovem
15.
Mo Med ; 111(4): 337-42, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25211865

RESUMO

Dengue virus is now the world's most common arboviral infection and has spread to the continental United States. The Aedes mosquito which transmits dengue is prevalent throughout Missouri, so clinicians should be familiar with dengue. While there are no licensed vaccines, five are in human trials including two tested at the Saint Louis University Center for Vaccine Development. Our deepening understanding of the correlates of protective immunity to dengue improves near-term prospects for a vaccine.


Assuntos
Vacinas contra Dengue , Dengue/prevenção & controle , Descoberta de Drogas/organização & administração , Pesquisa/organização & administração , Centros Médicos Acadêmicos , Dengue/diagnóstico , Dengue/transmissão , Humanos , Missouri
17.
Virology ; 456-457: 300-9, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24889249

RESUMO

We previously found that human pegivirus (HPgV; formerly GBV-C) NS3 protease activity inhibits Human Immunodeficiency Virus (HIV) replication in a CD4+ T cell line. Given the protease׳s similarity to the Hepatitis C virus (HCV) NS3 protease, we characterized HPgV protease activity and asked whether it affects the type I interferon response or is inhibited by HCV protease antagonists. We characterized the activity of proteases with mutations in the catalytic triad and demonstrated that the HCV protease inhibitors Telaprevir, Boceprevir, and Danoprevir do not affect HPgV protease activity. HPgV NS3 protease cleaved MAVS but not TRIF, and it inhibited interferon responses sufficiently to enhance growth of an interferon-sensitive virus. Therefore, HPgV׳s inhibition of the interferon response could help promote HPgV persistence, which is associated with clinical benefits in HIV-infected patients. Our results also imply that HCV protease inhibitors should not interfere with the beneficial effects of HPgV in HPgV/HCV/HIV infected patients.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Vírus GB C/enzimologia , Vírus GB C/imunologia , Interferon Tipo I/antagonistas & inibidores , Inibidores de Proteases/metabolismo , Proteínas não Estruturais Virais/metabolismo , Proteínas Adaptadoras de Transporte Vesicular/metabolismo , Linhagem Celular , Ciclopropanos , Análise Mutacional de DNA , Interações Hospedeiro-Patógeno , Humanos , Isoindóis , Lactamas/metabolismo , Lactamas Macrocíclicas , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , Oligopeptídeos/metabolismo , Prolina/análogos & derivados , Prolina/metabolismo , RNA Helicases/genética , RNA Helicases/metabolismo , Serina Endopeptidases/genética , Serina Endopeptidases/metabolismo , Sulfonamidas/metabolismo , Proteínas não Estruturais Virais/genética
18.
PLoS One ; 7(1): e30653, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22292009

RESUMO

INTRODUCTION: Persistent infection with GBV-C (GB Virus C), a non-pathogenic virus related to hepatitis C virus (HCV), prolongs survival in HIV infection. Two GBV-C proteins, NS5A and E2, have been shown previously to inhibit HIV replication in vitro. We investigated whether the GBV-C NS3 serine protease affects HIV replication. RESULTS: GBV-C NS3 protease expressed in a human CD4+ T lymphocyte cell line significantly inhibited HIV replication. Addition of NS4A or NS4A/4B coding sequence to GBV-C NS3 increased the effect on HIV replication. Inhibition of HIV replication was dose-dependent and was not mediated by increased cell toxicity. Mutation of the NS3 catalytic serine to alanine resulted in loss of both HIV inhibition and protease activity. GBV-C NS3 expression did not measurably decrease CD4 or CXCR4 expression. CONCLUSION: GBV-C NS3 serine protease significantly inhibited HIV replication without decreasing HIV receptor expression. The requirement for an intact catalytic serine at the active site indicates that inhibition was mediated by proteolytic cleavage of an unidentified target(s).


Assuntos
Linfócitos T CD4-Positivos/metabolismo , Vírus GB C/enzimologia , HIV-1/efeitos dos fármacos , Receptores de HIV/genética , Proteínas não Estruturais Virais/genética , Proteínas não Estruturais Virais/farmacologia , Replicação Viral/efeitos dos fármacos , Sequência de Aminoácidos , Fármacos Anti-HIV/metabolismo , Fármacos Anti-HIV/farmacologia , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/virologia , Linhagem Celular , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/genética , Vírus GB C/genética , Expressão Gênica/efeitos dos fármacos , Genoma Viral/genética , HIV-1/fisiologia , Humanos , Células Jurkat , Dados de Sequência Molecular , RNA Helicases/genética , RNA Helicases/metabolismo , RNA Helicases/farmacologia , RNA Helicases/fisiologia , Receptores de HIV/metabolismo , Homologia de Sequência de Aminoácidos , Serina Endopeptidases/genética , Serina Endopeptidases/metabolismo , Serina Endopeptidases/farmacologia , Serina Endopeptidases/fisiologia , Transfecção , Proteínas não Estruturais Virais/metabolismo , Proteínas não Estruturais Virais/fisiologia , Replicação Viral/genética
19.
J Infect Dis ; 205(5): 703-12, 2012 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-22275399

RESUMO

BACKGROUND: The immunogenicity of a high hemagglutinin (HA) dose or a second dose of influenza vaccine in human immunodeficiency virus (HIV)-infected individuals has not been fully explored. METHODS: One hundered ninety-two HIV-infected individuals aged 18-64 years were stratified by CD4 cell count (<200 cells/mL or ≥200 cells/mL) and randomized to receive 2 doses of 15 µg or 30 µg HA 2009 H1N1 vaccine 21 days apart. Hemagglutination inhibition (HAI) and microneutralization (MN) antibodies were measured on days 0, 10, 21, 31, 42, and 201. RESULTS: Recipients of 30 µg HA had significantly higher HAI geometric mean titers (GMTs), compared with recipients of 15 µg HA on days 10 (139.0 vs 51.9; P = .01), 21 (106.7 vs 51.9; P = .001), and 31 (130.0 vs 73.7; P = .03) but not on days 42 (91.8 vs 61.6; P = .11) and 201 (43.0 vs 27.0; P = .08). When analyzed by CD4 cell count stratum, HAI GMTs were significantly higher among 30 µg HA recipients than among 15 µg HA in the CD4 cell count <200 cells/mL stratum on days 21 and 31 and the MN GMTs on days 10, 21, 31, and 42 (P < .05). In the CD4 cell count ≥200 cells/mL stratum, MN GMTs were significantly higher among recipients of 30 µg HA than among recipients of 15 µg HA on day 10 (P = .03). CONCLUSION: Increasing the HA dose of the 2009 H1N1 vaccine improves the vaccine's immunogenicity in HIV-infected individuals. CLINICAL TRIALS REGISTRATION: NCT00992433.


Assuntos
Antígenos Virais/imunologia , Infecções por HIV/imunologia , Hemaglutininas/imunologia , Vírus da Influenza A Subtipo H1N1/imunologia , Vacinas contra Influenza/administração & dosagem , Vacinas contra Influenza/imunologia , Adolescente , Adulto , Contagem de Linfócito CD4 , Feminino , HIV-1/imunologia , Testes de Inibição da Hemaglutinação , Humanos , Vacinas contra Influenza/efeitos adversos , Masculino , Pessoa de Meia-Idade , Fatores de Tempo , Vacinas de Produtos Inativados/imunologia , Adulto Jovem
20.
Hepatology ; 49(3): 729-38, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19072828

RESUMO

UNLABELLED: One hundred fifty patients with sustained virologic response (SVR) after treatment of chronic hepatitis C were enrolled in a long-term clinical follow-up study; patients were followed for 5 years for liver-related outcomes and evidence of biochemical or virologic relapse. Patients with stage 2 or greater fibrosis on pretreatment biopsy were invited to undergo a long-term follow-up biopsy after their fourth year of follow-up. One hundred twenty-eight patients (85%) were followed through their fourth year, and long-term follow-up biopsies were obtained from 60 patients (40%). Forty-nine patients had paired pretreatment and long-term follow-up biopsies blindly rescored. Forty of these patients (82%) had a decrease in fibrosis score, and 45 (92%) had a decrease in combined inflammation score. Ten patients (20%) had normal or nearly normal livers on long-term follow-up biopsy. Two patients with pretreatment cirrhosis developed hepatocellular carcinoma (HCC), and one died. All the other patients with pretreatment cirrhosis or advanced fibrosis had improved fibrosis scores on long-term follow-up biopsy. No patient had conclusive evidence of virologic relapse. Three patients had persistently elevated alanine aminotransferase levels; two of these had new liver disease. CONCLUSION: In a cohort of 150 patients with SVR followed for 5 years, the majority of patients had good outcomes. Serum virologic relapse was not seen, but two patients with pretreatment cirrhosis developed HCC, and one died. In a blind rescoring of 49 paired pretreatment and long-term follow-up biopsies, 82% improved fibrosis scores and 92% improved at least one component of inflammation. A minority of patients had normal or nearly normal liver tissue on long-term follow-up biopsy. Patients with cirrhosis pretreatment are at a low but real risk of HCC after SVR.


Assuntos
Antivirais/uso terapêutico , Hepatite C/sangue , Hepatite C/tratamento farmacológico , Interferon-alfa/uso terapêutico , Fígado/patologia , Fígado/virologia , Ribavirina/uso terapêutico , Adulto , Idoso , Alanina Transaminase/sangue , Aspartato Aminotransferases/sangue , Biópsia , Quimioterapia Combinada , Feminino , Seguimentos , Genótipo , Hepacivirus/efeitos dos fármacos , Hepacivirus/genética , Hepacivirus/fisiologia , Hepatite C/patologia , Humanos , Interferon alfa-2 , Masculino , Pessoa de Meia-Idade , Polietilenoglicóis , Proteínas Recombinantes , Resultado do Tratamento
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