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1.
AIDS Care ; : 1-8, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38771971

RESUMO

The federal Ending the HIV Epidemic (EHE) initiative was created to reduce new US HIV infections, largely through pre-exposure prophylaxis and HIV treatments that reduce HIV transmissibility to zero. Behavioral health disorders (mental health and substance use) remain significant barriers to achieving EHE goals. Addressing behavioral health (BH) disorders within HIV primary care settings has been promoted as a critical EHE strategy. Implementation of efficacious HIV-BH care integration and its impact on HIV-related health outcomes is not well documented. In a federally-funded, exploratory phase implementation science study, we used the Collective Impact Framework to engage partners in seven EHE jurisdictions about the feasibility, acceptability, and sustainability of implementing HIV-BH integration interventions within local HIV settings. Partners concluded that full integration will remain the exception unless health systems invest in collaborative practice, professional training, appropriate health technology, and inter-system communication. Partners supported smaller incremental improvements including transdiagnostic approaches to reinforce each team member's sense of value in the shared endeavor. This early phase implementation science study identified research and implementation gaps that are critical to fill to end the HIV epidemic. Both the Collective Impact Framework and implementation science show promise for guiding future implementation of evidence-based HIV-BH intervention integration.

2.
Antiviral Res ; 171: 104597, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31494195

RESUMO

The New World alphaviruses Venezuelan, Eastern, and Western equine encephalitis viruses (VEEV, EEEV and WEEV, respectively) commonly cause a febrile disease that can progress to meningoencephalitis, resulting in significant morbidity and mortality. To address the need for a therapeutic agent for the treatment of Alphavirus infections, we identified and pursued preclinical characterization of a ribonucleoside analog EIDD-1931 (ß-D-N4-hydroxycytidine, NHC), which has shown broad activity against alphaviruses in vitro and has a very high genetic barrier for development of resistance. To be truly effective as a therapeutic agent for VEEV infection a drug must penetrate the blood brain barrier and arrest virus replication in the brain. High plasma levels of EIDD-1931 are rapidly achieved in mice after oral dosing. Once in the plasma EIDD-1931 is efficiently distributed into organs, including brain, where it is rapidly converted to its active 5'-triphosphate. EIDD-1931 showed a good safety profile in mice after 7-day repeated dosing with up to 1000 mg/kg/day doses. In mouse model studies, EIDD-1931 was 90-100% effective in protecting mice against lethal intranasal infection when therapeutic treatment was started as late as 24 h post-infection, and partial protection was achieved when treatment was delayed for 48 h post-infection. These results support further preclinical development of EIDD-1931 as a potential anti-alphavirus drug.


Assuntos
Antivirais/farmacologia , Vírus da Encefalite Equina Venezuelana/efeitos dos fármacos , Encefalomielite Equina Venezuelana/virologia , Ribonucleosídeos/farmacologia , Administração Oral , Animais , Antivirais/administração & dosagem , Antivirais/química , Antivirais/farmacocinética , Linhagem Celular , Cromatografia Líquida , Modelos Animais de Doenças , Encefalomielite Equina Venezuelana/tratamento farmacológico , Cavalos , Camundongos , Estrutura Molecular , Ribonucleosídeos/administração & dosagem , Ribonucleosídeos/química , Ribonucleosídeos/farmacocinética , Espectrometria de Massas em Tandem , Distribuição Tecidual , Replicação Viral/efeitos dos fármacos
3.
Artigo em Inglês | MEDLINE | ID: mdl-29180528

RESUMO

There is a growing body of evidence suggesting that some ribonucleoside/ribonucleotide analogs may be incorporated into mitochondrial RNA by human mitochondrial DNA-dependent RNA polymerase (POLRMT) and disrupt mitochondrial RNA synthesis. An assessment of the incorporation efficiency of a ribonucleotide analog 5'-triphosphate by POLRMT may be used to evaluate the potential mitochondrial toxicity of the analog early in the development process. In this report, we provide a simple method to prepare active recombinant POLRMT. A robust in vitro nonradioactive primer extension assay was developed to assay the incorporation efficiency of ribonucleotide analog 5'-triphosphates. Our results show that many ribonucleotide analogs, including some antiviral compounds currently in various preclinical or clinical development stages, can be incorporated into newly synthesized RNA by POLRMT and that the incorporation of some of them can lead to chain termination. The discrimination (D) values of ribonucleotide analog 5'-triphosphates over those of natural ribonucleotide triphosphates (rNTPs) were measured to evaluate the incorporation efficiency of the ribonucleotide analog 5'-triphosphates by POLRMT. The discrimination values of natural rNTPs under the condition of misincorporation by POLRMT were used as a reference to evaluate the potential mitochondrial toxicity of ribonucleotide analogs. We propose the following criteria for the potential mitochondrial toxicity of ribonucleotide analogs based on D values: a safe compound has a D value of >105; a potentially toxic compound has a D value of >104 but <105; and a toxic compound has a D value of <104 This report provides a simple screening method that should assist investigators in designing ribonucleoside-based drugs having lower mitochondrial toxicity.


Assuntos
RNA Polimerases Dirigidas por DNA/genética , Mitocôndrias/genética , Polifosfatos/farmacologia , RNA/efeitos dos fármacos , Ribonucleosídeos/genética , Ribonucleotídeos/farmacologia , Antivirais/farmacologia , Humanos , Mitocôndrias/efeitos dos fármacos , RNA/genética
4.
Artigo em Inglês | MEDLINE | ID: mdl-27993851

RESUMO

Zika virus (ZIKV) is an emerging human pathogen that is spreading rapidly through the Americas and has been linked to the development of microcephaly and to a dramatically increased number of Guillain-Barré syndrome cases. Currently, no vaccine or therapeutic options for the prevention or treatment of ZIKV infections exist. In the study described in this report, we expressed, purified, and characterized full-length nonstructural protein 5 (NS5) and the NS5 polymerase domain (NS5pol) of ZIKV RNA-dependent RNA polymerase. Using purified NS5, we developed an in vitro nonradioactive primer extension assay employing a fluorescently labeled primer-template pair. Both purified NS5 and NS5pol can carry out in vitro RNA-dependent RNA synthesis in this assay. Our results show that Mn2+ is required for enzymatic activity, while Mg2+ is not. We found that ZIKV NS5 can utilize single-stranded DNA but not double-stranded DNA as a template or a primer to synthesize RNA. The assay was used to compare the efficiency of incorporation of analog 5'-triphosphates by the ZIKV polymerase and to calculate their discrimination versus that of natural ribonucleotide triphosphates (rNTPs). The 50% inhibitory concentrations for analog rNTPs were determined in an alternative nonradioactive coupled-enzyme assay. We determined that, in general, 2'-C-methyl- and 2'-C-ethynyl-substituted analog 5'-triphosphates were efficiently incorporated by the ZIKV polymerase and were also efficient chain terminators. Derivatives of these molecules may serve as potential antiviral compounds to be developed to combat ZIKV infection. This report provides the first characterization of ZIKV polymerase and demonstrates the utility of in vitro polymerase assays in the identification of potential ZIKV inhibitors.


Assuntos
Antivirais/farmacologia , Bioensaio , RNA Polimerase Dependente de RNA/antagonistas & inibidores , Ribonucleotídeos/farmacologia , Proteínas não Estruturais Virais/antagonistas & inibidores , Replicação Viral/efeitos dos fármacos , Zika virus/efeitos dos fármacos , Antivirais/metabolismo , Sequência de Bases , Cátions Bivalentes , Primers do DNA/síntese química , Primers do DNA/metabolismo , DNA de Cadeia Simples/genética , DNA de Cadeia Simples/metabolismo , Manganês/metabolismo , Polifosfatos/metabolismo , Domínios Proteicos , RNA Viral/antagonistas & inibidores , RNA Viral/biossíntese , RNA Viral/genética , RNA Polimerase Dependente de RNA/genética , RNA Polimerase Dependente de RNA/metabolismo , Ribonucleotídeos/metabolismo , Coloração e Rotulagem/métodos , Proteínas não Estruturais Virais/genética , Proteínas não Estruturais Virais/metabolismo , Zika virus/genética , Zika virus/metabolismo
5.
Bioorg Med Chem Lett ; 17(12): 3398-401, 2007 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-17434736

RESUMO

A series of 2'-substituted cyclobutyl nucleoside analogs were efficiently prepared by constructing the core cyclobutyl ring using different [2+2] cycloaddition approaches. The triphosphate derivative of a cyclobutyl nucleoside was also synthesized and evaluated against wild-type and mutant HIV reverse transcriptases (RT). Whereas the nucleoside analogs were inactive against HIV-1 in culture, the nucleotide showed good activity not only against wild-type and recombinant HIV RT (IC(50)=4.7, 6.9 microM), but also against the M184I and M184V mutants (IC(50)=6.1, 6.9 microM) in cell-free assays.


Assuntos
Fármacos Anti-HIV/farmacologia , Ciclobutanos/química , Nucleosídeos/farmacologia , Nucleotídeos/farmacologia , Inibidores da Transcriptase Reversa/farmacologia , Fármacos Anti-HIV/síntese química , Sítios de Ligação , Células Cultivadas , Ciclobutanos/farmacologia , Farmacorresistência Viral , Humanos , Modelos Químicos , Nucleosídeos/química , Nucleotídeos/química , Mutação Puntual , Inibidores da Transcriptase Reversa/síntese química , Relação Estrutura-Atividade
6.
Water Res ; 36(10): 2582-8, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-12153025

RESUMO

In this work several feed-forward back propagation neural networks (FFBP) were trained in order to model, and subsequently control, methane production in anaerobic digesters. To produce data for the training of the neural nets, four anaerobic continuous stirred tank reactors were operated in steady-state conditions at organic loading rates (Br) of about 2 kg m(-3) d(-1) chemical oxygen demand, and disturbed by pulse-like increase of the organic loading rate. For the pulses additional carbon sources like flour, sucrose, 1,2-diethylen glycol or vegetable oil were added to the basic feed, which consisted of surplus and primary sludge of a local waste-water treatment plant, to increase the chemical oxygen demand. Measured parameters were: gas composition, methane production rate, volatile fatty acid concentration, pH, redox potential, volatile suspended solids and chemical oxygen demand of feed and effluent. A hierarchical system of nets was developed and embedded in a decision support system to find out which is the best feeding profile for the next time steps in advance. A 3-3-1 FFBP simulated the pH with a regression coefficient of 0.82. A 9-3-3 FFBP simulated the volatile fatty acid concentration in the sludge with a regression coefficient of 0.86. And a 9-3-2 FFBP simulated the gas production and gas composition with a regression coefficient of 0.90 and 0.80, respectively. A lab-scale anaerobic continuous stirred tank reactor controlled by this tool was able to maintain a methane concentration of about 60% at a rather high gas production rate of between 5 and 5.6 m3 m(-3) d(-1).


Assuntos
Bactérias Anaeróbias/fisiologia , Reatores Biológicos , Modelos Teóricos , Redes Neurais de Computação , Eliminação de Resíduos Líquidos/métodos , Fermentação , Previsões , Concentração de Íons de Hidrogênio , Metano/análise , Análise de Regressão
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