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1.
BJOG ; 127(2): 182-192, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31749298

RESUMO

OBJECTIVE: Characterise the vaginal metabolome of cervical HPV-infected and uninfected women. DESIGN: Cross-sectional. SETTING: The Center for Health Behavior Research at the University of Maryland School of Public Health. SAMPLE: Thirty-nine participants, 13 categorised as HPV-negative and 26 as HPV-positive (any genotype; HPV+ ), 14 of whom were positive with at least one high-risk HPV strain (hrHPV). METHOD: Self-collected mid-vaginal swabs were profiled for bacterial composition by 16S rRNA gene amplicon sequencing, metabolites by both gas and liquid chromatography mass spectrometry, and 37 types of HPV DNA. MAIN OUTCOME MEASURES: Metabolite abundances. RESULTS: Vaginal microbiota clustered into Community State Type (CST) I (Lactobacillus crispatus-dominated), CST III (Lactobacillus iners-dominated), and CST IV (low-Lactobacillus, 'molecular-BV'). HPV+ women had higher biogenic amine and phospholipid concentrations compared with HPV- women after adjustment for CST and cigarette smoking. Metabolomic profiles of HPV+ and HPV- women differed in strata of CST. In CST III, there were higher concentrations of biogenic amines and glycogen-related metabolites in HPV+ women than in HPV- women. In CST IV, there were lower concentrations of glutathione, glycogen, and phospholipid-related metabolites in HPV+ participants than in HPV- participants. Across all CSTs, women with hrHPV strains had lower concentrations of amino acids, lipids, and peptides compared with women who had only low-risk HPV (lrHPV). CONCLUSIONS: The vaginal metabolome of HPV+ women differed from HPV- women in terms of several metabolites, including biogenic amines, glutathione, and lipid-related metabolites. If the temporal relation between increased levels of reduced glutathione and oxidised glutathione and HPV incidence/persistence is confirmed in future studies, anti-oxidant therapies may be considered as a non-surgical HPV control intervention. TWEETABLE ABSTRACT: Metabolomics study: Vaginal microenvironment of HPV+ women may be informative for non-surgical interventions.


Assuntos
Metaboloma , Microbiota , Infecções por Papillomavirus/microbiologia , Vagina/microbiologia , Adulto , Estudos Transversais , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Lactobacillus , Microbiota/genética , Infecções por Papillomavirus/genética , Infecções por Papillomavirus/virologia , RNA Ribossômico 16S/genética , Vagina/virologia
2.
Sci Rep ; 8(1): 852, 2018 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-29339821

RESUMO

Cigarette smoking has been associated with both the diagnosis of bacterial vaginosis (BV) and a vaginal microbiota lacking protective Lactobacillus spp. As the mechanism linking smoking with vaginal microbiota and BV is unclear, we sought to compare the vaginal metabolomes of smokers and non-smokers (17 smokers/19 non-smokers). Metabolomic profiles were determined by gas and liquid chromatography mass spectrometry in a cross-sectional study. Analysis of the 16S rRNA gene populations revealed samples clustered into three community state types (CSTs) ---- CST-I (L. crispatus-dominated), CST-III (L. iners-dominated) or CST-IV (low-Lactobacillus). We identified 607 metabolites, including 12 that differed significantly (q-value < 0.05) between smokers and non-smokers. Nicotine, and the breakdown metabolites cotinine and hydroxycotinine were substantially higher in smokers, as expected. Among women categorized to CST-IV, biogenic amines, including agmatine, cadaverine, putrescine, tryptamine and tyramine were substantially higher in smokers, while dipeptides were lower in smokers. These biogenic amines are known to affect the virulence of infective pathogens and contribute to vaginal malodor. Our data suggest that cigarette smoking is associated with differences in important vaginal metabolites, and women who smoke, and particularly women who are also depauperate for Lactobacillus spp., may have increased susceptibilities to urogenital infections and increased malodor.


Assuntos
Fumar Cigarros , Metaboloma , Vagina/metabolismo , Adulto , Agmatina/metabolismo , Estudos Transversais , Dipeptídeos/metabolismo , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Lactobacillus/classificação , Lactobacillus/genética , Lactobacillus/isolamento & purificação , Pessoa de Meia-Idade , Nicotina/metabolismo , Filogenia , Análise de Componente Principal , RNA Ribossômico 16S/química , RNA Ribossômico 16S/classificação , RNA Ribossômico 16S/metabolismo , Vagina/microbiologia , Adulto Jovem
3.
J Environ Radioact ; 126: 77-82, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23968753

RESUMO

Assessments of radon and gamma radiation levels were carried out in underground artisanal gold mines in Tongo. This is one of the numerous artisanal gold mining communities in Ghana. Solid State Nuclear Track Detectors (SSNTDs) were used to estimate the mean (222)Rn concentration and dose rates during the Harmattan season (November 2010 to February 2011). The values for the (222)Rn concentration at each monitoring site ranged from 14 ± 4 Bq m(-3) to 270 ± 9 Bq m(-3), with a mean value of 98 Bq m(-3). These measurements are well below the lower action level of 500 Bq m(-3) recommended by ICRP for workplaces. The activity concentrations of (40)K, (232)Th and (238)U were determined using gamma-ray spectroscopy method. The effective dose estimates of 0.11 ± 0.02 mSv y(-1) to 0.68 ± 0.04 mSv y(-1) were below the allowable limit of 20 mSv per annum for occupational exposure control recommended by the ICRP. The total annual effective dose varied from 0.22 ± 0.04 mSv y(-1) to 1.92 ± 0.08 mSv y(-1).


Assuntos
Mineração , Exposição Ocupacional/análise , Monitoramento de Radiação , Ouro , Humanos , Radioisótopos de Potássio/análise , Radônio/análise , Tório/análise , Urânio/análise
4.
Clin Pharmacol Ther ; 89(3): 392-9, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21270788

RESUMO

NicVAX, a nicotine vaccine (3'AmNic-rEPA), has been clinically evaluated to determine whether higher antibody (Ab) concentrations are associated with higher smoking abstinence rates and whether dosages and frequency of administration are associated with increased Ab response. This randomized, double-blinded, placebo-controlled multicenter clinical trial (N = 301 smokers) tested the results of 200- and 400-µg doses administered four or five times over a period of 6 months, as compared with placebo. 3'AmNic-rEPA recipients with the highest serum antinicotine Ab response (top 30% by area under the curve (AUC)) were significantly more likely than the placebo recipients (24.6% vs. 12.0%, P = 0.024, odds ratio (OR) = 2.69, 95% confidence interval (CI), 1.14-6.37) to attain 8 weeks of continuous abstinence from weeks 19 through 26. The five-injection, 400-µg dose regimen elicited the greatest Ab response and resulted in significantly higher abstinence rates than placebo. This study demonstrates, as proof of concept, that 3'AmNic-rEPA elicits Abs to nicotine and is associated with higher continuous abstinence rates (CAR). Its further development as a treatment for nicotine dependence is therefore justified.


Assuntos
Nicotina/imunologia , Abandono do Hábito de Fumar/métodos , Tabagismo/reabilitação , Vacinas Conjugadas/uso terapêutico , Vacinas/uso terapêutico , Adulto , Anticorpos/imunologia , Área Sob a Curva , Relação Dose-Resposta a Droga , Método Duplo-Cego , Esquema de Medicação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tabagismo/imunologia , Resultado do Tratamento , Vacinas/administração & dosagem , Vacinas/imunologia , Vacinas Conjugadas/administração & dosagem , Vacinas Conjugadas/imunologia
5.
Health Phys ; 98 Suppl 2: S33-8, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20386190

RESUMO

The use of nuclear gauges for process control and elemental analysis in the mining industry in Ghana, West Africa, is wide spread and on the increase in recent times. The Ghana Radiation Protection Board regulates nuclear gauges through a system of notification and authorization by registration or licensing, inspection, and enforcement. Safety assessments for authorization and enforcement have been established to ensure the safety and security of radiation sources as well as protection of workers and the general public. Appropriate training of mine staff is part of the efforts to develop the necessary awareness about the safety and security of radiation sources. The knowledge and skills acquired will ensure the required protection and safety at the workplaces. Doses received by workers monitored over a period between 1998 and 2007 are well below the annual dose limit of 20 mSv recommended by the International Commission on Radiological Protection.


Assuntos
Física Médica/instrumentação , Mineração , Exposição Ocupacional/prevenção & controle , Monitoramento de Radiação/instrumentação , Proteção Radiológica/instrumentação , Relação Dose-Resposta à Radiação , Gana , Humanos , Exposição Ocupacional/análise , Exposição Ocupacional/legislação & jurisprudência , Monitoramento de Radiação/legislação & jurisprudência , Proteção Radiológica/legislação & jurisprudência , Radiometria , Medição de Risco/métodos , Fatores de Tempo , Local de Trabalho
6.
J Appl Physiol (1985) ; 107(3): 645-54, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19608931

RESUMO

Unloading-induced atrophy is a relatively uncomplicated form of muscle loss, dependent almost solely on the loss of mechanical input, whereas in disease states associated with inflammation (cancer cachexia, AIDS, burns, sepsis, and uremia), there is a procatabolic hormonal and cytokine environment. It is therefore predictable that muscle loss mainly due to disuse alone would be governed by mechanisms somewhat differently from those in inflammatory states. We suggest that in vivo measurements made in human subjects using arterial-venous balance, tracer dilution, and tracer incorporation are dynamic and thus robust by comparison with static measurements of mRNA abundance and protein expression and/or phosphorylation in human muscle. In addition, measurements made with cultured cells or in animal models, all of which have often been used to infer alterations of protein turnover, appear to be different from results obtained in immobilized human muscle in vivo. In vivo measurements of human muscle protein turnover in disuse show that the primary variable that changes facilitating the loss of muscle mass is protein synthesis, which is reduced in both the postabsorptive and postprandial states; muscle proteolysis itself appears not to be elevated. The depressed postprandial protein synthetic response (a phenomenon we term "anabolic resistance") may even be accompanied by a diminished suppression of proteolysis. We therefore propose that most of the loss of muscle mass during disuse atrophy can be accounted for by a depression in the rate of protein synthesis. Thus the normal diurnal fasted-to-fed cycle of protein balance is disrupted and, by default, proteolysis becomes dominant but is not enhanced.


Assuntos
Proteínas Musculares/metabolismo , Músculo Esquelético/metabolismo , Transtornos Musculares Atróficos/metabolismo , Animais , Humanos , Camundongos , Músculo Esquelético/anatomia & histologia , Tamanho do Órgão/fisiologia , Ratos , Especificidade da Espécie
7.
Naturwissenschaften ; 90(9): 395-401, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-14504781

RESUMO

Arsenic, a carcinogenic trace element, threatens not only the health of millions of humans and other living organisms, but also global sustainability. We present here, for the first time, the global industrial-age cumulative anthropogenic arsenic production and its potential accumulation and risks in the environment. In 2000, the world cumulative industrial-age anthropogenic arsenic production was 4.53 million tonnes. The world-wide coal and petroleum industries accounted for 46% of global annual gross arsenic production, and their overall contribution to industrial-age gross arsenic production was 27% in 2000. Global industrial-age anthropogenic As sources (as As cumulative production) follow the order: As mining production>As generated from coal>As generated from petroleum. The potential industrial-age anthropogenic arsenic input in world arable surface in 2000 was 2.18 mg arsenic kg(-1), which is 1.2 times that in the lithosphere. The development of substitute materials for arsenic applications in the agricultural and forestry industries and controls of arsenic emissions from the coal industry may be possible strategies to significantly decrease arsenic pollution sources and dissipation rates into the environment.


Assuntos
Arsênio/toxicidade , Poluentes Ambientais/toxicidade , Indústrias , Animais , Carcinógenos/toxicidade , Humanos
8.
Hum Gene Ther ; 14(1): 37-44, 2003 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-12573057

RESUMO

Recombinant vectors based on adeno-associated virus (AAV) can efficiently transduce many different cell types, including cells of the retina, resulting in stable gene expression. A major shortcoming of this vector is its small packaging capacity. A trans-splicing approach, which reconstitutes gene expression from two independent AAV vectors, can be used to overcome the vector's packaging limitations. The efficiency of this system to date has been disappointing, and therefore its utility for therapeutic application limited. We demonstrate here that efficiency and cellular specificity of trans-splicing is dependent on selection of the appropriate AAV serotype. Efficiency of transgene expression resulting from trans-splicing in skeletal muscle approaches that obtained when delivering the intact transgene when using AAV2 vectors packaged with AAV5 capsids (AAV2/5). This expands the potential of AAV vectors for retinal gene therapy. The use of AAV2/5 also increases the efficiency of trans-splicing in photoreceptors. Selection of the appropriate AAV serotype is likely to affect efficiency of trans-splicing in other organ systems as well.


Assuntos
Dependovirus/genética , Terapia Genética/métodos , Vetores Genéticos/genética , Retina/fisiologia , Trans-Splicing , Animais , Sequência de Bases , Capsídeo , Células Cultivadas , Regulação da Expressão Gênica , Humanos , Camundongos , Camundongos Endogâmicos , Dados de Sequência Molecular , Músculo Esquelético/fisiologia , Especificidade de Órgãos , Sorotipagem , Transgenes , beta-Galactosidase/genética , beta-Galactosidase/metabolismo
9.
Nicotine Tob Res ; 3(2): 131-40, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11403727

RESUMO

A population pharmacokinetic and pharmacodynamic analysis evaluated the relationships of dose, plasma concentrations of bupropion and metabolites, and patient covariates with the safety and efficacy of bupropion sustained release (SR) for smoking cessation. A total of 519 outpatient chronic cigarette smokers were randomized to one of three bupropion SR doses: 100, 150, or 300 mg/day or placebo. The bupropion plasma concentration time data were fit and subject-specific bayesian estimates of clearance were obtained. Logistic regression analyses evaluated the role of dose, concentrations, and covariates in predicting efficacy and safety endpoints. For the evaluation of efficacy, patients were classified as quitters or non-quitters on the basis of a 4-week quit variable (defined as complete abstinence for weeks 4-7 of the study). For the evaluation of safety, patients were classified into two categories for each adverse event evaluated, corresponding to whether the patient ever experienced the adverse event during the course of the study or never experienced the event, regardless of whether the event was treatment-emergent. The efficacy of bupropion SR in facilitating smoking cessation was found to be related to dose and a mean metabolite concentration, and quitting in general was found to be related to the number of cigarettes smoked per day at baseline. Smoking cessation was 1.42, 1.69, and 2.84 times more likely in patients receiving 100, 150, and 300 mg/day of bupropion SR, respectively, as compared to placebo (p = 0.0001). As the baseline number of cigarettes smoked per day increased, the likelihood of quitting decreased regardless of the treatment condition. Insomnia and dry mouth were positively associated with mean metabolite concentrations, and dry mouth was inversely related to patient weight. Anxiety was inversely related to predicted steady-state concentration (Cpss), suggesting a positive effect on this withdrawal symptom. Bupropion SR exhibits a statistically significant dose/plasma level-response relationship for smoking cessation. Dry mouth and insomnia, related to concentrations, may be managed with dose reduction, with the realization that smoking cessation may be impaired.


Assuntos
Bupropiona/uso terapêutico , Qualidade de Produtos para o Consumidor , Inibidores da Captação de Dopamina/uso terapêutico , Prevenção do Hábito de Fumar , Tabagismo/reabilitação , Adolescente , Bupropiona/administração & dosagem , Preparações de Ação Retardada , Inibidores da Captação de Dopamina/administração & dosagem , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Humanos , Masculino , Abandono do Hábito de Fumar/métodos , Fatores de Tempo , Resultado do Tratamento
10.
Chest ; 119(5): 1357-64, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11348939

RESUMO

OBJECTIVES: To identify predictors of smoking abstinence at the end of medication use that could assist in the optimal use of a sustained-release (SR) form of bupropion for treating cigarette smokers. DESIGN: A double-blind, placebo-controlled, dose-response trial. SETTING: Multicenter (three sites) study conducted in the United States. PARTICIPANTS: Six hundred fifteen healthy men and women (> or = 18 years of age) who were smoking > or = 15 cigarettes per day and who were motivated to stop smoking. INTERVENTION: Random assignment of patients to placebo or SR bupropion treatment, 100, 150, or 300 mg/d, for 7 weeks (total duration of study was 52 weeks: 7 weeks of treatment and 45 weeks of follow-up). MEASUREMENTS AND RESULTS: Logistic regression was used to identify predictors of abstinence at the end of the medication phase. Univariate predictors included the following: bupropion dose (p < 0.001); older age (p = 0.024); lower number of cigarettes smoked per day (cpd) (p < 0.001); lower Fagerström Tolerance Questionnaire score (p = 0.011); longest time previously abstinent that was < 24 h or > 4 weeks (p < 0.001); absence of other smokers in the household (p = 0.021); greater number of previous stop attempts (p = 0.019); and study site (p = 0.004). Multivariate predictors of abstinence at the end of the medication phase were the following: higher bupropion dose (p < 0.001); lower number of cpd (p < 0.001); longest time previously abstinent from smoking (p = 0.002); male gender (p = 0.014); and study site (p = 0.021). CONCLUSION: Bupropion SR therapy was effective in treating cigarette smokers independently of all other characteristics studied. Lower smoking rate, brief periods (ie, < 24 h) or long periods (ie, > 4 weeks) of abstinence with previous attempts to stop smoking, and male gender were predictive of better outcomes, independent of the dose of bupropion that was used.


Assuntos
Bupropiona/uso terapêutico , Inibidores da Captação de Dopamina/uso terapêutico , Abandono do Hábito de Fumar , Adulto , Idoso , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Indução de Remissão
11.
Am J Health Behav ; 25(3): 179-82, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11322615

RESUMO

OBJECTIVE: To explore the biology of nicotine addiction and to investigate the latest pharmacological treatments for nicotine dependence. METHODS: Explore the research literature for treating nicotine dependence. RESULTS: Nicotine is an additive drug and the most effective methods for treating dependence are nicotine replacement therapy (NRT) and bupropion SR. CONCLUSION: The best available treatments for nicotine dependence are pharmacological adjuncts; specifically, NRT and bupropion SR when combined with behavioral counseling.


Assuntos
Bupropiona/administração & dosagem , Inibidores da Captação de Dopamina/administração & dosagem , Nicotina/administração & dosagem , Tabagismo/tratamento farmacológico , Humanos , Fumar/tratamento farmacológico , Fumar/metabolismo , Síndrome de Abstinência a Substâncias , Tabagismo/metabolismo , Estados Unidos
12.
W V Med J ; 97(1): 39-43, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11257836

RESUMO

To explore the biology of nicotine addiction and to discuss the latest effective treatments for nicotine dependence. Research indicates that the most effective methods for treating nicotine dependence are nicotine replacement therapy (NRT) and bupropion SR (BUP). We conclude that pharmacological adjuncts (NRT & BUP) achieve their greatest success when combined with behavioral counseling.


Assuntos
Nicotina , Abandono do Hábito de Fumar/métodos , Transtornos Relacionados ao Uso de Substâncias/reabilitação , Terapia Comportamental , Bupropiona/administração & dosagem , Humanos , Nicotina/administração & dosagem , Guias de Prática Clínica como Assunto , Síndrome de Abstinência a Substâncias/reabilitação
13.
Nicotine Tob Res ; 2(4): 319-25, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11197311

RESUMO

The objectives of this study are to identify knowledge and attitude variables that correlate with smokeless tobacco use and how youth users and non-users differ in their attitudes and knowledge about smokeless tobacco. A randomized cluster sample of 1834 total fifth, eighth, and 11th grade students in West Virginia public schools during the 1996-1997 school year were surveyed on smokeless tobacco knowledge, attitudes and practices. Data from 648 male non-users and 160 male monthly and daily users of smokeless tobacco were compared using chi 2 and two-tailed t-tests. Logistic regression analysis of survey variables revealed the following correlates of smokeless tobacco use: having a family member not living in the home who uses, having a friend who uses, playing football, having tried cigarettes, and having parents who would permit use at home. Important differences exist in knowledge and attitudes regarding smokeless tobacco between users and non-users in fifth, eighth, and 11th grade West Virginia public schools. Correlates of smokeless tobacco use are identified which can be used to target prevention programs.


Assuntos
Comportamento do Adolescente , Conhecimentos, Atitudes e Prática em Saúde , Plantas Tóxicas , Tabaco sem Fumaça , Adolescente , Criança , Relações Familiares , Feminino , Inquéritos Epidemiológicos , Humanos , Masculino , Grupo Associado , Fatores de Risco , Instituições Acadêmicas , Esportes
14.
Proc Natl Acad Sci U S A ; 96(17): 9920-5, 1999 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-10449795

RESUMO

Recombinant adeno-associated virus (rAAV) is a promising vector for therapy of retinal degenerative diseases. We evaluated the efficiency, cellular specificity, and safety of retinal cell transduction in nonhuman primates after subretinal delivery of an rAAV carrying a cDNA encoding green fluorescent protein (EGFP), rAAV. CMV.EGFP. The treatment results in efficient and stable EGFP expression lasting >1 year. Transgene expression in the neural retina is limited exclusively to rod photoreceptors. There is neither electroretinographic nor histologic evidence of photoreceptor toxicity. Despite significant serum antibody responses to the vector, subretinal readministration results in additional transduction events. The findings further characterize the retinal cell tropism of rAAV. They also support the development of studies aimed ultimately at treating inherited retinal degeneration by using rAAV-mediated gene therapy.


Assuntos
Regulação da Expressão Gênica , Técnicas de Transferência de Genes , Células Fotorreceptoras de Vertebrados/metabolismo , Retina/metabolismo , Transgenes , Animais , DNA Recombinante/metabolismo , Dependovirus , Ensaio de Imunoadsorção Enzimática , Vetores Genéticos , Proteínas de Fluorescência Verde , Proteínas Luminescentes/genética , Macaca mulatta , Microscopia de Fluorescência
15.
Br J Psychiatry ; 174: 173-8, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10211174

RESUMO

BACKGROUND: A past history of major depression or alcoholism has been associated with poorer smoking treatment outcomes. AIM: To evaluate the efficacy of bupropion for smoking cessation in smokers with a former history of major depression or alcoholism, and changes in depressive symptoms during smoking abstinence. METHOD: Data were drawn from a multicentre trial of bupropion for smoking cessation. Smokers (n = 615) received placebo or bupropion sustained-release at 100, 150, or 300 mg/day for six weeks after target quit date (TQD). The primary outcome was the point prevalence smoking abstinence at the end of treatment and at one year. The Beck Depression Inventory (BDI) was used to assess depressive symptoms. RESULTS: A significant dose-response effect of bupropion for smoking cessation was found. This was independent of history of major depression or alcoholism. Among those continuously abstinent from smoking for two weeks following TQD, an increase in BDI score was associated with a return to smoking at end of treatment. CONCLUSIONS: Bupropion is efficacious for smoking cessation independently of a former history of major depression or alcoholism. Increases in depressive symptoms during an initial period of abstinence are associated with a return to smoking.


Assuntos
Alcoolismo/complicações , Antidepressivos de Segunda Geração/uso terapêutico , Bupropiona/uso terapêutico , Transtorno Depressivo/complicações , Abandono do Hábito de Fumar/métodos , Adulto , Preparações de Ação Retardada , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Humanos , Masculino , Estudos Prospectivos , Resultado do Tratamento
16.
Prev Med ; 28(2): 113-8, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10048102

RESUMO

BACKGROUND: This study was undertaken to evaluate the long-term smoking cessation efficacy of varying doses of transdermal nicotine delivery systems 4 to 5 years post-quit day. METHODS: A follow-up study was conducted 48 to 62 months after quit day among patients who were enrolled in the Transdermal Nicotine Study Group investigation. The latter study included group smoking cessation counseling and randomized assignment to 21, 14, or 7 mg nicotine patches or placebo patches. Seven of nine smoking cessation research centers participated in the long term follow-up investigation. RESULTS: The self-reported continuous quit rate among patients originally assigned 21 mg (20.2%) was significantly higher than rates for patients assigned 14 mg (10.4%), 7 mg (11.8%), or placebo patches (7.4%). Log rank survival analysis found no difference in relapse rates after 1 year postcessation. Smokers under age 30 years were significantly less likely to be abstinent at long term follow-up compared to smokers > or = 30 years of age (3 vs 13%, respectively). Mean weight gain in confirmed continuous quitters was 10.1 kg in men and 8.0 kg in women. Of the 63 continuous abstainers surveyed, 30 respondents (48%) reported that they no longer craved cigarettes, and no individual reported daily craving for cigarettes. CONCLUSIONS: Nicotine patch therapy with 21 mg/day patches resulted in a significantly higher long-term continuous abstinence rate compared to lower dose patches and placebo. Relapse rates among the various treatment conditions were similar after 1 year postcessation.


Assuntos
Nicotina/administração & dosagem , Agonistas Nicotínicos/administração & dosagem , Abandono do Hábito de Fumar/métodos , Tabagismo/terapia , Administração Cutânea , Adulto , Comportamento Aditivo/psicologia , Distribuição de Qui-Quadrado , Relação Dose-Resposta a Droga , Feminino , Seguimentos , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Motivação , Recidiva , Análise de Sobrevida , Fatores de Tempo , Resultado do Tratamento , Aumento de Peso
17.
N Engl J Med ; 337(17): 1195-202, 1997 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-9337378

RESUMO

BACKGROUND AND METHODS: Trials of antidepressant medications for smoking cessation have had mixed results. We conducted a double-blind, placebo-controlled trial of a sustained-release form of bupropion for smoking cessation. We excluded smokers with current depression, but not those with a history of major depression. The 615 subjects were randomly assigned to receive placebo or bupropion at a dose of 100, 150, or 300 mg per day for seven weeks. The target quitting date (or "target quit date") was one week after the beginning of treatment. Brief counseling was provided at base line, weekly during treatment, and at 8, 12, 26, and 52 weeks. Self-reported abstinence was confirmed by a carbon monoxide concentration in expired air of 10 ppm or less. RESULTS: At the end of seven weeks of treatment, the rates of smoking cessation as confirmed by carbon monoxide measurements were 19.0 percent in the placebo group, 28.8 percent in the 100-mg group, 38.6 percent in the 150-mg group, and 44.2 percent in the 300-mg group (P<0.001). At one year the respective rates were 12.4 percent, 19.6 percent, 22.9 percent, and 23.1 percent. The rates for the 150-mg group (P=0.02) and the 300-mg group (P=0.01) -- but not the 100-mg group (P=0.09) -- were significantly better than those for the placebo group. Among the subjects who were continuously abstinent through the end of treatment, the mean absolute weight gain was inversely associated with the dose (a gain of 2.9 kg in the placebo group, 2.3 kg in 100-mg and 150-mg groups, and 1.5 kg in the 300-mg group; P= 0.02). No effects of treatment were observed on depression scores as measured serially by the Beck Depression Inventory. Thirty-seven subjects stopped treatment prematurely because of adverse events; the frequency was similar among all groups. CONCLUSIONS: A sustained-release form of bupropion was effective for smoking cessation and was accompanied by reduced weight gain and minimal side effects. Many participants in all groups were smoking at one year.


Assuntos
Antidepressivos de Segunda Geração/administração & dosagem , Bupropiona/administração & dosagem , Abandono do Hábito de Fumar/métodos , Adulto , Antidepressivos de Segunda Geração/efeitos adversos , Bupropiona/efeitos adversos , Preparações de Ação Retardada , Depressão , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Nicotina/efeitos adversos , Abandono do Hábito de Fumar/estatística & dados numéricos , Síndrome de Abstinência a Substâncias/tratamento farmacológico , Tabagismo/tratamento farmacológico , Aumento de Peso/efeitos dos fármacos
20.
Arch Biochem Biophys ; 310(1): 218-28, 1994 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8161208

RESUMO

The mammalian aromatic hydrocarbon (Ah) receptor is a soluble protein involved in the regulation of gene expression by halogenated aromatic hydrocarbons such as 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Little is known, however, about the presence and properties of this receptor in nonmammalian species. In these studies, we sought evidence for an Ah receptor in the liver or liver-equivalent of diverse species of invertebrate and vertebrate animals. Velocity sedimentation analysis of hepatic cytosol labeled with [3H]TCDD gave equivocal results with three species of marine fish. In subsequent studies, photoaffinity labeling with 2-azido-3-[125I]iodo-7,8-dibromodibenzo-p-dioxin was used to identify the Ah receptor. Specific labeling (labeling that could be displaced by an excess of unlabeled ligand) was observed in seven species of teleost and elasmobranch fish, including winter flounder (Pleuronectes americanus), killifish (Fundulus heteroclitus), scup (Stenotomus chrysops), rainbow trout (Oncorhynchus mykiss), brown trout (Salmo trutta), and dogfish (Mustelus canis and Squalus acanthias). Specific labeling was also found in cytosolic fractions prepared from PLHC-1 fish hepatoma cells and livers of a turtle (Chrysemys picta) and a cetacean, the beluga whale Delphinapterus leucas. The fish Ah receptor was sensitive to conditions of tissue preparation; inclusion of proteinase inhibitors in the homogenization buffer stabilized the receptor in some species. There was heterogeneity in the apparent molecular mass of the largest specifically labeled band in each species; these ranged from 105 to 146 kDa, slightly larger on average than mammalian Ah receptors (95-130 kDa). In contrast to the results obtained with teleost and elasmobranch fish, no specifically labeled polypeptides were detectable in cytosol from two agnathan fish species (hagfish Myxine glutinosa and sea lamprey Petromyzon marinus), the tunicate Ciona intestinalis, or any of nine other invertebrate species representing eight classes in four phyla. Overall these results suggest that the Ah receptor evolved at least 450 million years ago, prior to the divergence of bony and cartilaginous fishes. Although the exact relationship between receptor presence and dioxin responsiveness in these species is uncertain, our data predict that the invertebrate species examined in this study, which appear to lack an Ah receptor protein like that seen in mammals and fish, may be less sensitive than vertebrates to the effects of environmental contaminants that act through this transcriptional regulator.


Assuntos
Marcadores de Afinidade , Invertebrados/metabolismo , Fígado/metabolismo , Receptores de Hidrocarboneto Arílico/metabolismo , Animais , Citosol/metabolismo , Feminino , Peixes/metabolismo , Masculino , Peso Molecular , Dibenzodioxinas Policloradas/metabolismo , Inibidores de Proteases/farmacologia , Receptores de Hidrocarboneto Arílico/efeitos dos fármacos , Receptores de Hidrocarboneto Arílico/isolamento & purificação , Caracteres Sexuais , Especificidade da Espécie , Vertebrados/metabolismo
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