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1.
Mo Med ; 119(5): 474-478, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36338005

RESUMO

The rate of maternal mortality in the United States (U.S.) is higher than any other industrialized nation, at 23.8 per 100,000 deliveries from 2000-2014. Although maternal mortality ratios decreased by 44% globally from 1990 to 2015, emerging evidence suggests that maternal mortality in the U.S. has been increasing.2-4 One study quotes 700 maternal deaths every year, with 50,000 "near misses."1 By one metric, Missouri ranks as the 44th-worst state for maternal mortality in the U.S.5.


Assuntos
Mortalidade Materna , Estados Unidos , Humanos , Missouri/epidemiologia
2.
J Acquir Immune Defic Syndr ; 89(2): 191-198, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-34654041

RESUMO

BACKGROUND: MK-8507 is a novel HIV-1 non-nucleoside reverse transcriptase inhibitor being developed for treatment of HIV-1 infection. MK-8507 has high antiviral potency in vitro and pharmacokinetic (PK) properties that support once-weekly dosing. SETTING: A phase 1, open-label, proof-of-concept study was conducted in treatment-naive adults with HIV-1 infection to assess monotherapy antiviral activity. METHODS: In 3 sequential panels, participants aged 18-60 years with baseline plasma HIV-1 RNA ≥10,000 copies/mL and CD4+ T-cell count >200/mm3 received a single oral dose of 40, 80, or 600 mg MK-8507 in the fasted state. Participants were assessed for HIV-1 RNA for at least 7 days, PKs for 14 days, and safety and tolerability for 21 days postdose. RESULTS: A total of 18 participants were enrolled (6 per panel). The mean 7-day postdose HIV-1 RNA reduction ranged from ∼1.2 to ∼1.5 log10 copies/mL across the doses assessed. One patient had a viral rebound associated with emergence of an F227C reverse transcriptase variant (per chain-termination method sequencing) 14 days postdose; this variant was found in a second participant by ultra-deep sequencing as an emerging minority variant. MK-8507 PKs were generally dose-proportional and similar to observations in participants without HIV-1 infection in prior studies; mean MK-8507 half life was 56-69 hours in this study. MK-8507 was generally well tolerated at all doses. CONCLUSIONS: The robust antiviral activity, PK, and tolerability of MK-8507 support its continued development as part of a complete once weekly oral regimen for HIV-1 treatment; combination therapy could mitigate the emergence of resistance-associated variants.


Assuntos
Fármacos Anti-HIV , Infecções por HIV , HIV-1 , Adolescente , Adulto , Contagem de Linfócito CD4 , Infecções por HIV/tratamento farmacológico , HIV-1/genética , Humanos , Pessoa de Meia-Idade , RNA , RNA Viral , Inibidores da Transcriptase Reversa/efeitos adversos , Carga Viral , Adulto Jovem
3.
J Clin Pharmacol ; 62(2): 190-198, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34432899

RESUMO

Chronic overexposure to fluoride can have deleterious effects in the musculoskeletal system. Some fluorine-containing therapeutics, such as voriconazole, release fluoride through metabolism. Therefore, drug-related fluoride exposure should be assessed for novel therapeutics suspected of releasing fluoride through metabolism. Two trials were conducted to identify the optimal method of assessing drug-related fluoride exposure. In trial 1, designed to assess reproducibility of fluoride pharmacokinetics in urine and plasma, 14 participants were administered a fluoride-restricted diet and once-daily doses of sodium fluoride (2.2 mg [1 mg of fluoride] on days 1 and 2; and 13.2 mg of sodium fluoride [6 mg of fluoride] on days 3 and 4). In trial 2, designed to confirm the selected method for fluoride detection, 12 participants were administered a fluoride-restricted diet and randomized to receive voriconazole (400 mg twice, 12 hours apart, on day 1 [131 mg/d of fluoride maximum], then 3 doses of 200 mg every 12 hours [65.3 mg/d of fluoride maximum]) or placebo. Plasma fluoride concentrations and urinary fluoride excretion were assessed in each trial. Assessment of plasma fluoride concentrations in trial 1 was limited by 301 of 854 samples (35.2%) below the lower limit of quantitation. Urine fluoride excretion was readily measured and demonstrated a decrease from baseline during the fluoride-restricted diet phase, as well as dose-proportional increases with fluoride administration. In trial 2, increases in urine fluoride were successfully observed in participants administered voriconazole. In conclusion, fluoride exposure was optimally assessed by urinary fluoride excretion in conjunction with strict dietary fluoride restrictions, as measurements were consistent and reproducible.


Assuntos
Fluoretos/administração & dosagem , Fluoretos/urina , Fluoreto de Sódio/administração & dosagem , Fluoreto de Sódio/urina , Adulto , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Método Simples-Cego , Voriconazol/química , Adulto Jovem
4.
J Clin Pharmacol ; 62(2): 199-205, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34435371

RESUMO

MK-8507 is an investigational HIV-1 nonnucleoside reverse transcriptase inhibitor being developed for the treatment of HIV-1 infection. MK-8507 contains 2 trifluoromethyl groups that may result in fluoride release through metabolism, but the extent of MK-8507-related fluoride release in humans has yet to be determined. This double-blind, placebo-controlled, 2-period, parallel-group, multiple-dose trial in healthy participants without HIV-1 who were administered a fluoride-restricted diet and once-weekly doses of MK-8507 aimed to estimate the relationship between MK-8507 dose and fluoride exposure. A total of 15 adult male and 3 adult female (of non-childbearing potential) participants were randomized to receive MK-8507 200 mg (n = 6), MK-8507 800 mg (n = 6), or placebo (n = 6). Change from baseline in mean daily fluoride excretion averaged over 7 days following the administration of MK-8507 200 mg resulted in a net mean increase of 19.8 µmol (90% confidence interval, 12.2-27.4) relative to placebo and did not exceed 57 µmol, a threshold related to the mean difference between the daily reference dose set by the US Environmental Protection Agency and the average dietary fluoride intake in the United States. However, daily urinary fluoride excretion exceeded the threshold following administration of 800 mg MK-8507 (75.1 µmol [90% confidence interval, 67.5-82.7]). Assuming a linear relationship between MK-8507 dose and estimated mean daily fluoride released at steady-state, data interpolation suggests that the US Environmental Protection Agency reference dose for fluoride would not be exceeded in most patients when administering MK-8507 at doses currently under clinical investigation (≤400 mg once weekly).


Assuntos
Fluoretos , Inibidores da Transcriptase Reversa , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Relação Dose-Resposta a Droga , Método Duplo-Cego , Fluoretos/sangue , Fluoretos/urina , Infecções por HIV/tratamento farmacológico , Inibidores da Transcriptase Reversa/farmacocinética , Inibidores da Transcriptase Reversa/uso terapêutico
5.
Psychopharmacology (Berl) ; 238(12): 3533-3541, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34477886

RESUMO

RATIONALE: Common pharmacological treatments for attention-deficit hyperactivity disorder (ADHD) are central nervous system stimulants acting as norepinephrine-dopamine reuptake inhibitors. The noradrenergic and dopaminergic systems have been shown to impact performance on tasks assessing creativity. Some previous studies suggest higher performance on creativity tasks in ADHD. Stimulant medication has been shown to differentially impact creativity in those without ADHD. However, the full range of effects of stimulant medication on creativity in those with ADHD is not known. OBJECTIVES: This study examined the effects of stimulants on convergent and divergent tasks associated with creativity in adults with ADHD. METHOD: Seventeen adults diagnosed with ADHD who were prescribed stimulant medication attended two counterbalanced sessions: one after taking their prescribed stimulant dose and one after the dose was withheld. Participants completed convergent problem-solving (anagrams, Compound Remote Associates) and divergent generative (letter/semantic fluency, Torrance Test for Creative Thinking (TTCT)-Verbal) tasks. RESULTS: There was a significant increase in words generated on the semantic fluency task for the stimulant session. Additionally, significant increases were found in the stimulant session for originality, flexibility, and fluency scores on the TTCT. Stimulant medication did not have an effect on any of the problem-solving tasks. CONCLUSIONS: Stimulant medication enhanced verbal fluency in adults with ADHD but had no effect on convergent abilities. Furthermore, stimulants enhanced fluency, flexibility, and originality scores on the TTCT. Therefore, stimulants appear to have positive effects on divergent task performance in adults with ADHD, but not convergent tasks. This finding warrants further studies into the specific roles of norepinephrine and dopamine in this effect.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Estimulantes do Sistema Nervoso Central , Adulto , Transtorno do Deficit de Atenção com Hiperatividade/tratamento farmacológico , Estimulantes do Sistema Nervoso Central/uso terapêutico , Criatividade , Humanos , Resolução de Problemas , Análise e Desempenho de Tarefas
6.
Antimicrob Agents Chemother ; 65(12): e0093521, 2021 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-34516246

RESUMO

MK-8507 is a novel HIV-1 nonnucleoside reverse transcriptase inhibitor in clinical development with potential for once-weekly oral administration for the treatment of HIV-1 infection. Two randomized, double-blind, placebo-controlled phase 1 studies in adults without HIV-1 evaluated the safety, tolerability, and pharmacokinetics of single and multiple doses of MK-8507; drug interaction with midazolam (a cytochrome P450 3A4 substrate) and food effect were also assessed. In study 1, 16 participants received oral ascending single doses of MK-8507 (2 to 400 mg) or placebo in an alternating fashion. In study 2, 24 participants received ascending single doses of MK-8507 (400 to 1,200 mg) or placebo and multiple doses (once weekly for 3 weeks) of MK-8507 (100 to 400 mg) or placebo. MK-8507 pharmacokinetics were approximately dose proportional at 2 to 1,200 mg. MK-8507 had a time to maximum concentration of 2 to 7 h and a mean terminal half-life of ∼58 to 84 h. MK-8507 doses of ≥100 mg achieved a plasma concentration at 168 h postdose (7 days) associated with antiviral efficacy. A high-fat meal had no clinically meaningful effect on MK-8507 pharmacokinetics, and MK-8507 400 mg once weekly had no clinically meaningful effect on midazolam pharmacokinetics. Single and multiple doses of MK-8507 were generally well tolerated. No trends with dose and no clinically meaningful changes were observed in vital signs, electrocardiograms, and laboratory safety tests. The pharmacokinetics and safety data are supportive of once-weekly oral administration and support further clinical investigation of MK-8507 for the treatment of HIV-1 infection.


Assuntos
Infecções por HIV , HIV-1 , Adulto , Área Sob a Curva , Relação Dose-Resposta a Droga , Método Duplo-Cego , Interações Medicamentosas , Infecções por HIV/tratamento farmacológico , Humanos , Inibidores da Transcriptase Reversa/efeitos adversos
7.
Lancet Infect Dis ; 16(8): 915-22, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27061887

RESUMO

BACKGROUND: The licensed live, attenuated varicella-zoster virus vaccine prevents herpes zoster in adults older than 50 years. We aimed to determine whether intradermal administration of zoster vaccine could enhance vaccine immunogenicity compared with conventional needle subcutaneous administration. METHODS: In this randomised, dose-ranging study, adults aged 50 years or older who had a history of varicella or who had resided in a country with endemic varicella-zoster virus infection for 30 years or more were eligible. Participants received the approved full or a 1/3 dose of zoster vaccine given subcutaneously or one of four intradermal doses (full, 1/3, 1/10, or 1/27 dose) using the MicronJet600 device. The two subcutaneous doses and the four intradermal doses were randomised (1·5:1:1:1:1:1) by computer generated sequence with randomisation stratified by age (50-59 years or 60 years or older). The primary immunogenicity endpoint was the change from baseline in IgG antibody to varicella-zoster virus-specific glycoproteins (gpELISA) measured at 6 weeks. All patients were included in the primary and safety analyses. This study is registered with ClinicalTrials.gov, number NCT01385566. FINDINGS: Between Sept 2, 2011, and Jan 13, 2012, 224 participants were enrolled from three clinics in the USA and 223 were randomly assigned: 52 to receive the full dose subcutaneous zoster vaccine, 34 to receive the 1/3 dose subcutaneous zoster vaccine, 34 to receive the full dose intradermal zoster vaccine, 35 to receive the 1/3 dose intradermal zoster vaccine, 34 to receive the 1/10 dose intradermal zoster vaccine, and 34 to receive the 1/27 dose intradermal zoster vaccine. Full dose zoster vaccine given subcutaneously resulted in a gpELISA geometric mean fold-rise (GMFR) of 1·74 (90% CI 1·48-2·04) at 6 weeks post-vaccination compared with intradermal administration which resulted in a significantly higher gpELISA GMFR of 3·25 (2·68-3·94; p<0·0001), which also remained high at 18 months. An apparent dose-response relation was observed with intradermal administration (1/3 dose subcutaneous GMFR 1·64 [90% CI 1·36-1·99], 1/3 dose intradermal 2·58 (2·13-3·13), 1/10 dose intradermal 2·22 [1·83-2·69], and 1/27 dose intradermal 1·64 [1·35-2·00]). Each partial dose of zoster vaccine given intradermaly had a gpELISA GMFR comparable to that of full dose zoster vaccine given subcutaneously. Transient erythema and induration were more common after intradermal administration (31% erythema for full subcutaneous dose and 77% for intradermal dose). INTERPRETATION: Intradermal zoster vaccine showed a greater increase in varicella-zoster virus gpELISA antibody compared with subcutaneous zoster vaccine at comparable doses. Larger and longer studies of intradermal administration of live, attenuated zoster vaccine are needed to provide convincing evidence of improved cell mediated immunity. FUNDING: Merck & Co Inc.


Assuntos
Relação Dose-Resposta Imunológica , Vacina contra Herpes Zoster/administração & dosagem , Herpes Zoster/prevenção & controle , Injeções Intramusculares/métodos , Injeções Subcutâneas/métodos , Idoso , Varicela/imunologia , Eritema/etiologia , Herpes Zoster/imunologia , Vacina contra Herpes Zoster/imunologia , Herpesvirus Humano 3/imunologia , Humanos , Esquemas de Imunização , Pessoa de Meia-Idade , Estados Unidos , Vacinação , Vacinas Atenuadas
8.
Nat Commun ; 7: 10369, 2016 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-26742691

RESUMO

Aging is associated with hyporesponse to vaccination, whose mechanisms remain unclear. In this study hepatitis B virus (HBV)-naive older adults received three vaccines, including one against HBV. Here we show, using transcriptional and cytometric profiling of whole blood collected before vaccination, that heightened expression of genes that augment B-cell responses and higher memory B-cell frequencies correlate with stronger responses to HBV vaccine. In contrast, higher levels of inflammatory response transcripts and increased frequencies of pro-inflammatory innate cells correlate with weaker responses to this vaccine. Increased numbers of erythrocytes and the haem-induced response also correlate with poor response to the HBV vaccine. A transcriptomics-based pre-vaccination predictor of response to HBV vaccine is built and validated in distinct sets of older adults. This moderately accurate (area under the curve≈65%) but robust signature is supported by flow cytometry and cytokine profiling. This study is the first that identifies baseline predictors and mechanisms of response to the HBV vaccine.


Assuntos
Envelhecimento/imunologia , Linfócitos B/fisiologia , Antígenos de Superfície da Hepatite B/imunologia , Vacinas contra Hepatite B/imunologia , Inflamação/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/metabolismo , Biomarcadores/sangue , Estudos de Coortes , Contagem de Eritrócitos , Feminino , Citometria de Fluxo , Humanos , Masculino , Pessoa de Meia-Idade , Transcriptoma , Vacinação
9.
J Transl Med ; 12: 178, 2014 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-24952610

RESUMO

BACKGROUND: Single-cell network profiling (SCNP) is a multiparametric flow cytometry-based approach that simultaneously measures evoked signaling in multiple cell subsets. Previously, using the SCNP approach, age-associated immune signaling responses were identified in a cohort of 60 healthy donors. METHODS: In the current study, a high-dimensional analysis of intracellular signaling was performed by measuring 24 signaling nodes in 7 distinct immune cell subsets within PBMCs in an independent cohort of 174 healthy donors [144 elderly (>65 yrs); 30 young (25-40 yrs)]. RESULTS: Associations between age and 9 immune signaling responses identified in the previously published 60 donor cohort were confirmed in the current study. Furthermore, within the current study cohort, 48 additional immune signaling responses differed significantly between young and elderly donors. These associations spanned all profiled modulators and immune cell subsets. CONCLUSIONS: These results demonstrate that SCNP, a systems-based approach, can capture the complexity of the cellular mechanisms underlying immunological aging. Further, the confirmation of age associations in an independent donor cohort supports the use of SCNP as a tool for identifying reproducible predictive biomarkers in areas such as vaccine response and response to cancer immunotherapies.


Assuntos
Envelhecimento/imunologia , Voluntários Saudáveis , Transdução de Sinais , Adulto , Idoso , Estudos de Coortes , Humanos
10.
Diabetes Ther ; 4(2): 431-42, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24163113

RESUMO

INTRODUCTION: Saxagliptin, sitagliptin, and vildagliptin are dipeptidyl peptidase-4 (DPP-4) inhibitors widely approved for use in patients with type 2 diabetes. Using a crossover design, the present study compared trough levels of DPP-4 inhibition provided by these agents in a single cohort of patients with type 2 diabetes. METHODS: This was a randomized, placebo-controlled, open-label, five-period crossover study. Eligible patients were 18-65 years of age, either treatment-naïve or off prior antihyperglycemic agent therapy for at least 6 or 12 weeks (depending on the prior therapy), and had glycated hemoglobin (HbA1C) ≥6.5% and ≤10.0%. In separate study periods, patients received 5 mg saxagliptin q.d. (saxa-5), 100 mg sitagliptin q.d. (sita-100), 50 mg vildagliptin q.d. (vilda-50-q.d.), 50 mg vildagliptin b.i.d. (vilda-50-b.i.d.), or placebo for 5 days. The primary endpoint was trough %DPP-4 inhibition, derived by comparing DPP-4 activity 24 h after the Day-5 morning dose with predose activity in the same period and analyzed using a linear mixed-effects model with fixed-effects terms for treatment and period. RESULTS: Mean (range) baseline HbA1C was 7.4% (6.4-9.0%; N = 22). Least-squares (LS) mean trough %DPP-4 inhibition was 73.5%, 91.7%, 28.9%, 90.6%, and 3.5% after saxa-5, sita-100, vilda-50-q.d., vilda-50-b.i.d., and placebo, respectively. In patients treated with sita-100, the LS-mean difference in trough %DPP-4 inhibition was 18.2% greater than with saxa-5 (p < 0.001), 62.9% greater than with vilda-50-q.d. (p < 0.001), 1.1% greater than with vilda-50-b.i.d. (p = 0.128), and 87.8% greater than with placebo (p < 0.001). Mean %DPP-4 inhibition was nearly maximal at 12 h postdose regardless of active treatment. Thus, these between-group comparisons at trough primarily reflected differences in duration of action. Adverse events reported during the study were transient and mild or moderate in intensity. CONCLUSION: Once daily treatment with sitagliptin provided trough DPP-4 inhibition significantly greater than saxagliptin or vildagliptin administered once daily, and similar to that provided by vildagliptin administered twice daily.

11.
J Magn Reson Imaging ; 36(2): 468-75, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22535478

RESUMO

PURPOSE: To assess the repeatability of measurement of lactate and other metabolites in tumors using magnetic resonance spectroscopy (MRS). MATERIALS AND METHODS: MRS with spectral editing for lactate was performed on 10 patients with astrocytoma (two Grade III, eight Grade IV) using an 8-channel receive coil at 3T. Lactate, lipid, choline, creatine, and N-acetyl aspartate (NAA) signals were measured in regions of tumor and contralateral white matter. Metabolites were quantified relative to unsuppressed water using LCModel fitting software. RESULTS: The within-patient coefficients of variation were ≈16% (tumor lactate), 6%-8% (tumor choline and contralateral choline, creatine, and NAA), and 22% (tumor lipid). As expected due to their low concentration in normal tissue, lactate and lipid were not reliably detected in white matter but were found at high levels in most tumors. NAA and creatine were lower in tumors than in normal white matter, and choline varied between above- and below-normal values. No consistent short-term variation in metabolite levels was observed, despite differences in the time elapsed since administration of contrast agent. CONCLUSION: MRS appears repeatable enough to provide longitudinal measures of metabolite content in tumors and contralateral tissue in the brain in vivo.


Assuntos
Astrocitoma/metabolismo , Biomarcadores Tumorais/análise , Neoplasias Encefálicas/metabolismo , Ácido Láctico/análise , Ácido Láctico/metabolismo , Espectroscopia de Ressonância Magnética/métodos , Astrocitoma/diagnóstico , Neoplasias Encefálicas/diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
12.
Rev. Fac. Odontol. Porto Alegre ; 41(2): 51-5, dez. 2000. tab, graf
Artigo em Português | LILACS, BBO - Odontologia | ID: biblio-856660

RESUMO

Este estudo comparou a prevalência e severidade da fluorose dentária em dois períodos de tempo (1987 e 1997/98) em duas cidades do Rio Grande do Sul (Brasil): Porto Alegre, com água artificialmente fluoretada e Arroio do Tigre com baixo conteúdo de flúor natural na água. Um grupo de estudantes com 8-9 anos de idade de Arroio do Tigre (110 em 1987 e 101 em 1998) e Porto Alegre (117 em 1987 e 135 em 1997) foram examinados. A concentração de flúor em Porto Alegre foi avaliada de 1979 a 1996, período correspondente a formação e maturação do eslmalte das crianças examinadas. Uma larga variação na concentração de flúor na água foi observada em Porto Alegre, variando entre 0,13 - 1,11 ppm F de 1979-1987 (10 meses sem fluoretação) e entre 0,10 - 1,02 ppm F de 1988-1996 (8 meses sem fluoretação). A classificação da severidade da fluorose dentária foi feita de acordo com o Índice de Thylstrup e Fejerskov após a remoção de placa e secagem dos dentes. Nas duas cidades a prevalência de fluorose aumentou entre os dois períodos. A percentagem de crianças com fluorose aumentou de 0 por cento para 29,7 por cento em Arroio do Tigre e de 7,7 por cento para 32,6 por cento em Porto Alegre entre os doi períodos estudados. A prevalência de crianças com fluorose foi similar em Arroio do Tigre e Porto Alegre em 1997/98 (p>0,05 por cento), entretanto a severidade da fluorose foi maior em Porto Alegre. Em 1987, as crianças em Porto Alegre apresentaram TF1 (6,84 por cento) e TF2 (0,86 por cento). Em 1997/98, as crianças de Arroio do Tigre apresentaram apenas TF1 (29,7 por cento), enquanto que em Porto Alegre elas apresentaram TF1 (28,15 por cento), TF2 (3,71 por cento) e TF3 (0,74 por cento). O aumento da prevalência e severidade da fluorose de 1987 para 1997/98 foi devido, provavelmente, ao uso intensivo de diferentes métodos de aplicação tópica combinados em Porto Alegre, à presença de flúor no suprimento de água


Assuntos
Humanos , Masculino , Feminino , Criança , Dentifrícios/efeitos adversos , Halogenação , Fluorose Dentária/epidemiologia
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