Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 155
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Addict Biol ; 28(7): e13288, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37369125

RESUMO

Preclinical and clinical work suggests that mifepristone may be a viable treatment for alcohol use disorder (AUD). This was a Phase 1/2, outpatient, cross-over, randomized, double-blind, placebo-controlled trial with non-treatment-seeking individuals with AUD (N = 32). We assessed safety, alcohol craving and consumption, after 1-week mifepristone 600 mg/day administration, in a human laboratory study comprised of a single oral yohimbine administration (32.4 mg), a cue-reactivity procedure and alcohol self-administration. Safety was monitored by adverse events and hemodynamic parameters, alcohol craving by alcohol craving questionnaire and cue-induced saliva output. During the alcohol self-administration, we assessed alcohol pharmacokinetics, subjective effects and consumption. Outcomes were assessed using Generalized Estimating Equations and mediation analysis. Mild-moderate adverse events were reported in both conditions. There was no statistically significant difference between mifepristone and placebo in alcohol pharmacokinetics and subjective effects. Furthermore, blood pressure increased only in the placebo condition after the stress-induced laboratory procedures. Mifepristone, compared to placebo, significantly reduced alcohol craving and increased cortisol levels. Mifepristone-induced cortisol increase was not a mediator of alcohol craving. Mifepristone, compared to placebo, did not reduce alcohol consumption in the laboratory or in a naturalistic setting. This study successfully translated a developed preclinical procedure to a human laboratory study, confirming the safety of mifepristone in people with AUD and providing evidence to its role in reducing alcohol craving under stress procedures. The lack of effects on alcohol drinking may be related to the selection of non-treatment seekers and suggests future treatment-oriented trials should investigate mifepristone in people with AUD.


Assuntos
Alcoolismo , Fissura , Humanos , Mifepristona/farmacologia , Mifepristona/uso terapêutico , Hidrocortisona/farmacologia , Alcoolismo/tratamento farmacológico , Consumo de Bebidas Alcoólicas , Etanol/farmacologia , Método Duplo-Cego
2.
N Engl J Med ; 378(6): 507-517, 2018 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-29414272

RESUMO

BACKGROUND: In randomized trials, prazosin, an α1-adrenoreceptor antagonist, has been effective in alleviating nightmares associated with post-traumatic stress disorder (PTSD) in military veterans. METHODS: We recruited veterans from 13 Department of Veterans Affairs medical centers who had chronic PTSD and reported frequent nightmares. Participants were randomly assigned to receive prazosin or placebo for 26 weeks; the drug or placebo was administered in escalating divided doses over the course of 5 weeks to a daily maximum of 20 mg in men and 12 mg in women. After week 10, participants continued to receive prazosin or placebo in a double-blind fashion for an additional 16 weeks. The three primary outcome measures were the change in score from baseline to 10 weeks on the Clinician-Administered PTSD Scale (CAPS) item B2 ("recurrent distressing dreams"; scores range from 0 to 8, with higher scores indicating more frequent and more distressing dreams); the change in score from baseline to 10 weeks on the Pittsburgh Sleep Quality Index (PSQI; scores range from 0 to 21, with higher scores indicating worse sleep quality); and the Clinical Global Impression of Change (CGIC) score at 10 weeks (scores range from 1 to 7, with lower scores indicating greater improvement and a score of 4 indicating no change). RESULTS: A total of 304 participants underwent randomization; 152 were assigned to prazosin, and 152 to placebo. At 10 weeks, there were no significant differences between the prazosin group and the placebo group in the mean change from baseline in the CAPS item B2 score (between-group difference, 0.2; 95% confidence interval [CI], -0.3 to 0.8; P=0.38), in the mean change in PSQI score (between-group difference, 0.1; 95% CI, -0.9 to 1.1; P=0.80), or in the CGIC score (between-group difference, 0; 95% CI, -0.3 to 0.3; P=0.96). There were no significant differences in these measures at 26 weeks (a secondary outcome) or in other secondary outcomes. At 10 weeks, the mean difference between the prazosin group and the placebo group in the change from baseline in supine systolic blood pressure was a decrease of 6.7 mm Hg. The adverse event of new or worsening suicidal ideation occurred in 8% of the participants assigned to prazosin versus 15% of those assigned to placebo. CONCLUSIONS: In this trial involving military veterans who had chronic PTSD, prazosin did not alleviate distressing dreams or improve sleep quality. (Funded by the Department of Veterans Affairs Cooperative Studies Program; PACT ClinicalTrials.gov number, NCT00532493 .).


Assuntos
Antagonistas de Receptores Adrenérgicos alfa 1/administração & dosagem , Sonhos/efeitos dos fármacos , Prazosina/administração & dosagem , Transtornos do Sono-Vigília/tratamento farmacológico , Transtornos de Estresse Pós-Traumáticos/tratamento farmacológico , Veteranos , Antagonistas de Receptores Adrenérgicos alfa 1/efeitos adversos , Adulto , Terapia Combinada , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Hospitais de Veteranos , Humanos , Masculino , Pessoa de Meia-Idade , Prazosina/efeitos adversos , Escalas de Graduação Psiquiátrica , Psicoterapia , Sono/efeitos dos fármacos , Transtornos de Estresse Pós-Traumáticos/psicologia , Transtornos de Estresse Pós-Traumáticos/terapia , Ideação Suicida , Falha de Tratamento , Estados Unidos
3.
Am J Addict ; 30(1): 88-91, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32488890

RESUMO

BACKGROUND AND OBJECTIVES: In this secondary analysis of a pilot clinical trial with individuals with alcohol and nicotine use disorders, we investigate the relationship between serum concentrations of oxytocin, ß-endorphin, melatonin, α-melanocyte-stimulating hormone, substance P, and orexin, with objective biomarkers (salivary cotinine and serum γ-glutamyl transferase [GGT]) as well as with self-reported smoking and alcohol drinking. METHODS: Biomarkers for a total of N = 19 participants were analyzed using multiplexed, competitive format immune-assay (peptides) and enzyme competitive immunoassay (saliva). A regression analysis using Pearson's correlation coefficient was utilized to determine correlations. We controlled for multiple comparisons, checked for collinearities, and ran two-sided statistical tests. RESULTS: We found significant positive correlations for cotinine and oxytocin (P = .002), ß-endorphin (P = .008), and orexin (P < .001), but not for either GGT or self-reported smoking or alcohol drinking. CONCLUSION AND SCIENTIFIC SIGNIFICANCE: These preliminary results suggest a relationship between cotinine and oxytocin, ß-endorphin, and orexin, which opens up new potential hypotheses on the potential role of these endocrine pathways in tobacco smokers. (Am J Addict 2021;30:88-91).


Assuntos
Alcoolismo/sangue , Cotinina/metabolismo , Orexinas/sangue , Ocitocina/sangue , Tabagismo/sangue , beta-Endorfina/sangue , Adulto , Consumo de Bebidas Alcoólicas/sangue , Feminino , Humanos , Masculino , Melatonina/sangue , Pessoa de Meia-Idade , Saliva/química , Fumar/sangue , Substância P/sangue , alfa-MSH/sangue , gama-Glutamiltransferase/sangue
4.
Am J Drug Alcohol Abuse ; 47(6): 760-768, 2021 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-34582281

RESUMO

BACKGROUND: Participants who are enrolled in randomized controlled trials (RCTs) may be more motivated to change their behaviors after being enrolled in a study and that motivation may vary by treatment status. OBJECTIVES: The objectives of this secondary analysis were to investigate if changes in alcohol-related behaviors/characteristics from the baseline to the randomization session differed overall and to assess those differences between non-treatment and treatment seeking individuals with alcohol use disorder (AUD). METHODS: Our sample included participants from eight RCTs conducted at Brown University (N = 281, 34% female). To assess differences across alcohol-related behaviors/characteristics, we investigated changes in craving (obsessive compulsive drinking scale) and alcohol drinking (percent abstinent days, drinks per week (DPW) and percent heavy drinking days (HDD)) overall and between treatment status. RESULTS: Results showed that there were baseline differences, such as increased AUD severity and craving for alcohol in treatment seeking participants (p's < .05) in the overall sample. Next, we showed that craving, DPW and HDD decreased and percent abstinent days increased from baseline to randomization (p's < .05). When controlling for treatment status and sociodemographic characteristics, treatment seeking, compared to non-treatment seeking participants, had a greater reduction in alcohol craving (p < .001) and a greater increase in percentage of drinking days (p < .01). CONCLUSIONS: These findings demonstrated that alcohol-related behaviors and characteristics changed after enrollment. Severity, craving and drinking behaviors also differed between treatment-seeking status, which can potentially impact medication development stages for AUD such as clinical trial eligibility, enrollment and study outcomes.


Assuntos
Alcoolismo , Consumo de Bebidas Alcoólicas , Alcoolismo/tratamento farmacológico , Fissura , Feminino , Humanos , Masculino , Distribuição Aleatória
5.
Alcohol Clin Exp Res ; 44(10): 2097-2108, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32997422

RESUMO

BACKGROUND: One of the challenges in early-stage clinical research aimed at developing novel treatments for alcohol use disorder (AUD) is that the enrolled participants are heavy drinkers, but do not seek treatment for AUD. AIMS: To compare nontreatment seekers with alcohol dependence (AD) from 4 human laboratory studies conducted at Brown University (N = 240; 65.4% male) to treatment seekers with AD from the multisite COMBINE study (N = 1,383; 69.1% male) across sociodemographic and alcohol-related clinical variables and to evaluate whether the variables that significantly differentiate the 2 samples predict the 3 main COMBINE clinical outcomes: time to relapse, percent days abstinent (PDA), and good clinical outcome. METHODS: Sample characteristics were assessed by parametric and nonparametric testing. Three regression models measured the association between the differing variables and the 3 main COMBINE clinical outcomes. RESULTS: The nontreatment seekers, compared to the treatment seekers, were more ethnically diverse, less educated, single, and working part-time or unemployed (p's < 0.05); they met fewer DSM-IV AD criteria and had significantly lower scores on alcohol-related scales (p's < 0.05); they were less likely to have a father with alcohol problems (p < 0.0001) and had a significantly earlier age of onset and longer duration of AD (p's < 0.05); they also had significantly more total drinks, drinks per drinking day, heavy drinking days (HDD), and lower PDA in the 30 days prior to baseline (p's < 0.0001 to <0.05). Having more HDD in the 30 days prior to baseline predicted all of the 3 COMBINE clinical outcomes. All the other characteristics mentioned above that differed significantly between the 2 groups predicted at least 1 of the 3 COMBINE clinical outcomes, except for level of education, age of onset, and duration of AD. CONCLUSIONS: The observed differences between groups should be considered in efforts across participant recruitment at different stages of the development of new treatments for AUD.


Assuntos
Alcoolismo/psicologia , Aceitação pelo Paciente de Cuidados de Saúde/psicologia , Acamprosato/administração & dosagem , Acamprosato/uso terapêutico , Adulto , Idade de Início , Dissuasores de Álcool/administração & dosagem , Dissuasores de Álcool/uso terapêutico , Alcoolismo/tratamento farmacológico , Alcoolismo/terapia , Estudos de Casos e Controles , Quimioterapia Combinada , Feminino , Humanos , Masculino , Naltrexona/administração & dosagem , Naltrexona/uso terapêutico , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Fatores Socioeconômicos , Resultado do Tratamento
6.
Alcohol Alcohol ; 55(6): 681-689, 2020 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-32666120

RESUMO

AIMS: We aim to describe alcohol consumption and related problems from a nationwide survey in 2010 in Samoa in association with sociodemographic variables as part of an intervention development. METHODS: The sample consisted of 3463 adults, 25-65 years of age. Participants self-reported alcohol consumption in the previous 12 months, patterns of drinking and alcohol-related psychosocial problems. Data about age, census region of residence, highest attained education level, employment, marital status, household assets score and current smoking status were gathered. RESULTS: More than one-third of men, 36.1%, and 4.1% of women consumed alcohol in the past year. There were greater proportions of alcohol users among younger adults, <45 years, in both men and women. Among men, being unemployed and residing outside of rural Savai'i and smoking cigarettes were associated with current alcohol use. Among women, tertiary education and cigarette smoking were strongly associated with alcohol use. Among alcohol consumers, almost 75% of both men and women reported being drunk more than once in the prior month, and 58% of men and 81% of women drank heavily, consuming >4 drinks for women and >5 drinks for men at least once per episode in the prior week. More men than women, 51% versus 26%, felt that alcohol consumption had interfered with their daily life. CONCLUSION: Our analyses identified correlates of alcohol consumption and associated problems that can help guide the development of targeted interventions for different sex and age groups to mitigate the social and physiological harms of alcohol misuse.


Assuntos
Consumo de Bebidas Alcoólicas/etnologia , Consumo de Bebidas Alcoólicas/tendências , Estudo de Associação Genômica Ampla/tendências , Inquéritos Epidemiológicos/tendências , Adulto , Consumo de Bebidas Alcoólicas/economia , Consumo de Bebidas Alcoólicas/psicologia , Estudos Transversais , Emprego/economia , Emprego/psicologia , Emprego/tendências , Feminino , Estudo de Associação Genômica Ampla/métodos , Inquéritos Epidemiológicos/métodos , Humanos , Masculino , Estado Civil/etnologia , Pessoa de Meia-Idade , Samoa/etnologia , Fatores Socioeconômicos
7.
Nicotine Tob Res ; 21(Suppl 1): S38-S45, 2019 12 23.
Artigo em Inglês | MEDLINE | ID: mdl-31867650

RESUMO

INTRODUCTION: The US Food and Drug Administration is considering implementing a reduced-nicotine standard for cigarettes. Given the high rate of smoking among people with serious mental illness (SMI), it is important to examine the responses of these smokers to very low nicotine content (VLNC) cigarettes. METHODS: This trial compared the effects of VLNC (0.4 mg nicotine/g tobacco) and normal nicotine content cigarettes (15.8 mg/g) over a 6-week period in non-treatment-seeking smokers with schizophrenia, schizoaffective disorder, or bipolar disorder (n = 58). Linear regression was used to examine the effects of cigarette condition on cigarettes per day, subjective responses, nicotine and tobacco toxicant exposure, craving, withdrawal symptoms, and psychiatric symptoms. RESULTS: At week 6, participants in the VLNC condition smoked fewer cigarettes per day, had lower breath carbon monoxide levels, lower craving scores, and rated their study cigarettes lower in satisfaction, reward, enjoyment, and craving reduction than those in the normal nicotine content condition (ps < .05). Week 6 psychiatric and extrapyramidal symptoms did not differ by condition, except for scores on a measure of parkinsonism, which were lower in the VLNC condition (p < .05). There were no differences across conditions on total nicotine exposure, 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol, withdrawal symptoms, or responses to abstinence. CONCLUSIONS: These results suggest that a reduced-nicotine standard for cigarettes would reduce smoking among smokers with SMI. However, the lack of effect on total nicotine exposure indicates VLNC noncompliance, suggesting that smokers with SMI may respond to a reduced-nicotine standard by substituting alternative forms of nicotine. IMPLICATIONS: Results from this trial suggest that a reduced-nicotine standard for cigarettes would reduce smoking rates and smoke exposure in smokers with SMI, without increasing psychiatric symptoms. However, noncompliance with VLNC cigarettes was observed, suggesting that these smokers might respond to a reduced-nicotine standard by substituting alternative forms of nicotine.


Assuntos
Transtornos Mentais , Nicotina , Abandono do Hábito de Fumar , Fumar , Adulto , Feminino , Humanos , Masculino , Transtornos Mentais/complicações , Transtornos Mentais/epidemiologia , Transtornos Mentais/psicologia , Pessoa de Meia-Idade , Fumar/epidemiologia , Fumar/psicologia , Abandono do Hábito de Fumar/métodos , Abandono do Hábito de Fumar/psicologia , Abandono do Hábito de Fumar/estatística & dados numéricos , Produtos do Tabaco
8.
Alcohol Alcohol ; 53(3): 268-276, 2018 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-29281033

RESUMO

AIMS: The goal of this study was to evaluate the efficacy of topiramate up to 200 mg/day and of aripiprazole up to 15 mg/day, alone and combined, in reducing alcohol-related outcomes in a human laboratory study. METHOD: This was a 5 week, between-subject, double-blind, placebo-controlled human laboratory study with topiramate [0 mg/day (placebo), 100 mg/day, 200 mg/day] and aripiprazole [0 mg/day (placebo), 7.5 mg/day, 15 mg/day] in 90 non-treatment seeking, heavy drinking, alcohol-dependent individuals. Main outcomes were the efficacy of 200 mg/day topiramate and 15 mg/day aripiprazole, alone and combined, in reducing drinks consumed during an alcohol self-administration procedure (human laboratory phase) and while receiving the study medications prior to the laboratory session (naturalistic drinking phase). Other outcomes in the laboratory phase included alcohol craving, and alcohol biphasic effects. RESULTS: In the human laboratory phase, topiramate 200 mg/day reduced alcohol craving [**P < 0.01] and amplified alcohol-induced stimulation [*P < 0.05], but did not reduce the number of drinks consumed. Topiramate 200 mg/day was also effective in reducing drinking days [*P < 0.05], and alcohol craving [*P < 0.05], in the naturalistic drinking phase. No significant findings were found for aripiprazole for any of the outcomes analyzed. CONCLUSION: Participants receiving 200 mg/day topiramate reported reduced alcohol drinking and craving, and increased alcohol-related stimulation. These findings provide further support for the role of topiramate as a pharmacological treatment for AUD. CLINICALTRIAL.GOV IDENTIFIER: NCT00884884. SHORT SUMMARY: This study tested topiramate and aripiprazole alone and in combination. The results replicate past findings and suggest that topiramate may be an effective treatment for alcohol use disorder. The present results suggest that the combination of topiramate and aripiprazole do not warrant further evaluation.


Assuntos
Bebidas Alcoólicas , Alcoolismo/tratamento farmacológico , Anticonvulsivantes/administração & dosagem , Antipsicóticos/administração & dosagem , Aripiprazol/administração & dosagem , Frutose/análogos & derivados , Adulto , Alcoolismo/diagnóstico , Alcoolismo/psicologia , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Frutose/administração & dosagem , Humanos , Masculino , Pessoa de Meia-Idade , Topiramato , Resultado do Tratamento
9.
Addict Biol ; 22(3): 779-790, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-26752416

RESUMO

Cannabis misuse accounts for nearly all of the substance abuse treatment admissions among youth in the United States. Most youth do not experience sustained benefit from existing psychosocial treatments; however, medication development research for treating adolescent cannabis misuse is almost nonexistent. We conducted a double-blind, placebo-controlled, pilot study to test the potential efficacy of topiramate plus motivational enhancement therapy (MET) for treating cannabis use among adolescents. Sixty-six heavy cannabis users, ages 15 to 24 years, were randomized to one of two 6-week treatment conditions: topiramate plus MET or placebo plus MET. Topiramate was titrated over 4 weeks then stabilized at 200 mg/day for 2 weeks. MET was delivered biweekly for a total of three sessions. Only 48 percent of youths randomized to topiramate completed the 6-week trial (n = 19), compared with 77 percent of youths in the placebo condition (n = 20). Adverse medication side effects were the most common reason for withdrawal among participants in the topiramate group. Latent growth models showed that topiramate was superior to placebo for reducing the number of grams smoked per use day, but it did not improve abstinence rates. The same pattern of results was found when values for missing outcomes were imputed. We show that topiramate combined with MET demonstrated efficacy for reducing how much cannabis adolescents smoked when they used but did not affect abstinence rates. The magnitude of this effect was modest, however, and topiramate was poorly tolerated by youths, which calls into question the clinical importance of these findings.


Assuntos
Frutose/análogos & derivados , Abuso de Maconha/terapia , Entrevista Motivacional/métodos , Fármacos Neuroprotetores/uso terapêutico , Adolescente , Adulto , Método Duplo-Cego , Estudos de Viabilidade , Retroalimentação Psicológica , Feminino , Frutose/uso terapêutico , Humanos , Masculino , Abuso de Maconha/tratamento farmacológico , Projetos Piloto , Topiramato , Resultado do Tratamento , Adulto Jovem
10.
Int J Neuropsychopharmacol ; 19(10)2016 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-27207912

RESUMO

BACKGROUND: Increasing evidence supports a role for appetite-regulating pathways like ghrelin, insulin, and leptin in alcoholism. We previously reported that intravenous (i.v.) exogenous ghrelin increases alcohol craving. We also reported i.v. ghrelin reduces endogenous serum leptin, whose levels, in turn, negatively correlated with alcohol craving. Exogenous ghrelin administration decreases insulin secretion both in vitro and in vivo experiments. This study tested the hypothesis that i.v. ghrelin may also decrease endogenous serum insulin levels in alcoholic individuals. Additionally, we explored possible correlations between serum insulin and alcohol craving, since a correlation between insulin and alcohol craving was previously reported. METHODS: This was a double-blind, placebo-controlled human laboratory study ( n =43). Non-treatment-seeking, alcohol-dependent, heavy drinkers were randomized to receive i.v. ghrelin or placebo, followed by an alcohol cue-reactivity procedure. RESULTS: There was a main effect for i.v. ghrelin, compared to placebo in reducing serum insulin ( P <.05). There was also a time effect ( P <.001) but not ghrelin x time interaction ( P >.05). We did not find a correlation between the reduction of serum insulin and alcohol craving ( P >.05). The change in serum insulin was consistent with a parallel reduction in serum connective-peptide in the ghrelin group compared with placebo, although this difference did not reach statistical significance ( P =.076). No similar effects were found for other glucose-regulating hormones analyzed i.e. glucagon, glucagon-like peptide-1, and gastric inhibitory peptide ( P s>.05). CONCLUSIONS: These findings indicate i.v. ghrelin administration has an effect on reducing serum insulin in alcohol-dependent individuals; however, the reduction of insulin did not correlate with changes in alcohol cue-elicited craving. We speculate that, unlike for leptin, the interactions between ghrelin and insulin relationship are limited at the peripheral level. However, mechanistic studies are needed to investigate this hypothesis.

11.
Dis Colon Rectum ; 59(10): 925-33, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27602923

RESUMO

BACKGROUND: Pathological complete response after chemoradiotherapy for rectal cancer occurs in 10% to 30% of patients. The best method to identify such patients remains unclear. Clinical assessment of residual mucosal abnormality is considered the most accurate method. In our institution, magnetic resonance tumor regression grade is performed as routine to assess response. OBJECTIVE: The purpose of this study was to compare the sensitivity of magnetic tumor regression grade against residual mucosal abnormality in detecting patients with a pathological complete response. DESIGN: Magnetic tumor regression grade scores from reported posttreatment MRI scans were documented. Magnetic tumor regression grade 1 to 3 was defined as likely to predict complete or near complete response. Gross appearances of the mucosa were derived from histopathology reports and used as a surrogate for clinical assessment (previously validated). Final histopathological staging was used to determine response. SETTINGS: The study was conducted at Royal Marsden National Health Service Trust, United Kingdom. PATIENTS: A total of 143 patients with rectal adenocarcinoma, diagnosed between September 1, 2009, and September 1, 2013, who received neoadjuvant chemoradiotherapy before curative surgery were included. MAIN OUTCOME MEASURES: The sensitivity of magnetic tumor regression grade and residual mucosal abnormality in detecting patients with pathological complete response were measured RESULTS: : Eighteen patients had a pathological complete response. Seventeen were detected using magnetic resonance tumor regression grade 1 to 3, with sensitivity 94% (95% CI, 0.74-0.99), and 10 were detected using residual mucosal abnormality, with sensitivity 62% (95% CI, 0.38-0.81). There was no statistical difference between the false positive rates for either method. Magnetic tumor regression grade identified 10 times more patients with a pathological complete response (diagnostic OR = 10.2 (95% CI, 1.30-73.73)) compared with clinical assessment with RMA. LIMITATIONS: Residual mucosal abnormality was used as a surrogate marker for endoscopic appearances. CONCLUSIONS: Most patients with rectal cancer who have a pathological complete response do not manifest a complete response at the mucosal level. Magnetic tumor regression grade is able to identify 10 times more patients than clinical assessment, with no significant compromise in the false positive rate.


Assuntos
Adenocarcinoma , Quimiorradioterapia/métodos , Mucosa Intestinal , Imageamento por Ressonância Magnética/métodos , Neoplasia Residual/diagnóstico , Neoplasias Retais , Adenocarcinoma/diagnóstico , Adenocarcinoma/patologia , Adenocarcinoma/terapia , Idoso , Biópsia/métodos , Feminino , Humanos , Mucosa Intestinal/diagnóstico por imagem , Mucosa Intestinal/patologia , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante/métodos , Estadiamento de Neoplasias , Valor Preditivo dos Testes , Prognóstico , Neoplasias Retais/diagnóstico , Neoplasias Retais/patologia , Neoplasias Retais/terapia , Projetos de Pesquisa
12.
J Chem Inf Model ; 56(10): 1923-1935, 2016 10 24.
Artigo em Inglês | MEDLINE | ID: mdl-27662181

RESUMO

In silico virtual screening (VS) is a powerful hit identification technique used in drug discovery projects that aims to effectively distinguish true actives from inactive or decoy molecules. To better capture the dynamic behavior of protein drug targets, compound databases may be screened against an ensemble of protein conformations, which may be experimentally determined or generated computationally, i.e. via molecular dynamics (MD) simulations. Several studies have shown that conformations generated by MD are useful in identifying novel hit compounds, in part because structural rearrangements sampled during MD can provide novel targetable areas. However, it remains difficult to predict a priori when an MD conformation will outperform a VS against the crystal structure alone. Here, we assess whether MD conformations result in improved VS performance for six protein kinases. MD conformations are selected using three different methods, and their VS performances are compared to the corresponding crystal structures. Additionally, these conformations are used to train ensembles, and their VS performance is compared to the individual MD conformations and the corresponding crystal structures using receiver operating characteristic curve (ROC) metrics. We show that performing MD results in at least one conformation that offers better VS performance than the crystal structure, and that, while it is possible to train ensembles to outperform the crystal structure alone, the extent of this enhancement is target dependent. Lastly, we show that the optimal structural selection method is also target dependent and recommend optimizing virtual screens on a kinase-by-kinase basis to improve the likelihood of success.


Assuntos
Simulação de Dinâmica Molecular , Proteínas Quinases/química , Descoberta de Drogas/métodos , Humanos , Ligantes , Simulação de Acoplamento Molecular , Ligação Proteica , Conformação Proteica , Proteínas Quinases/metabolismo
13.
J Chem Inf Model ; 56(5): 830-42, 2016 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-27097522

RESUMO

Ensemble docking can be a successful virtual screening technique that addresses the innate conformational heterogeneity of macromolecular drug targets. Yet, lacking a method to identify a subset of conformational states that effectively segregates active and inactive small molecules, ensemble docking may result in the recommendation of a large number of false positives. Here, three knowledge-based methods that construct structural ensembles for virtual screening are presented. Each method selects ensembles by optimizing an objective function calculated using the receiver operating characteristic (ROC) curve: either the area under the ROC curve (AUC) or a ROC enrichment factor (EF). As the number of receptor conformations, N, becomes large, the methods differ in their asymptotic scaling. Given a set of small molecules with known activities and a collection of target conformations, the most resource intense method is guaranteed to find the optimal ensemble but scales as O(2(N)). A recursive approximation to the optimal solution scales as O(N(2)), and a more severe approximation leads to a faster method that scales linearly, O(N). The techniques are generally applicable to any system, and we demonstrate their effectiveness on the androgen nuclear hormone receptor (AR), cyclin-dependent kinase 2 (CDK2), and the peroxisome proliferator-activated receptor δ (PPAR-δ) drug targets. Conformations that consisted of a crystal structure and molecular dynamics simulation cluster centroids were used to form AR and CDK2 ensembles. Multiple available crystal structures were used to form PPAR-δ ensembles. For each target, we show that the three methods perform similarly to one another on both the training and test sets.


Assuntos
Avaliação Pré-Clínica de Medicamentos/métodos , Aprendizado de Máquina , Simulação de Dinâmica Molecular , Conformação Proteica , Interface Usuário-Computador
14.
J Chem Inf Model ; 56(4): 721-33, 2016 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-27043429

RESUMO

Predicting the rate of nonfacilitated permeation of solutes across lipid bilayers is important to drug design, toxicology, and signaling. These rates can be estimated using molecular dynamics simulations combined with the inhomogeneous solubility-diffusion model, which requires calculation of the potential of mean force and position-dependent diffusivity of the solute along the transmembrane axis. In this paper, we assess the efficiency and accuracy of several methods for the calculation of the permeability of a model DMPC bilayer to urea, benzoic acid, and codeine. We compare umbrella sampling, replica exchange umbrella sampling, adaptive biasing force, and multiple-walker adaptive biasing force for the calculation of the transmembrane PMF. No definitive advantage for any of these methods in their ability to predict the membrane permeability coefficient Pm was found, provided that a sufficiently long equilibration is performed. For diffusivities, a Bayesian inference method was compared to a generalized Langevin method, both being sensitive to chosen parameters and the slow relaxation of membrane defects. Agreement within 1.5 log units of the computed Pm with experiment is found for all permeants and methods. Remaining discrepancies can likely be attributed to limitations of the force field as well as slowly relaxing collective movements within the lipid environment. Numerical calculations based on model profiles show that Pm can be reliably estimated from only a few data points, leading to recommendations for calculating Pm from simulations.


Assuntos
Permeabilidade da Membrana Celular , Bicamadas Lipídicas/metabolismo , Modelos Moleculares , Teorema de Bayes , Ácido Benzoico/metabolismo , Codeína/metabolismo , Dimiristoilfosfatidilcolina/química , Dimiristoilfosfatidilcolina/metabolismo , Bicamadas Lipídicas/química , Conformação Molecular , Ureia/metabolismo
15.
Addict Biol ; 21(4): 904-14, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26037245

RESUMO

Evidence suggests that the norepinephrine system represents an important treatment target for alcohol dependence (AD) and the α1 -blocker prazosin may reduce alcohol drinking in rodents and alcoholic patients. The α1 -blocker doxazosin demonstrates a more favorable pharmacokinetic profile than prazosin, but has never been studied for AD. A double-blind placebo-controlled randomized clinical trial was conducted in AD individuals seeking outpatient treatment. Doxazosin or matched placebo was titrated to 16 mg/day (or maximum tolerable dose). Drinks per week (DPW) and heavy drinking days (HDD) per week were the primary outcomes. Family history density of alcoholism (FHDA), severity of AD and gender were a priori moderators. Forty-one AD individuals were randomized, 30 (doxazosin = 15) completed the treatment phase and 28 (doxazosin = 14) also completed the follow-up. There were no significant differences between groups on DPW and HDD per week. With FHDA as a moderator, there were significant FHDA × medication interactions for both DPW (pcorrected = 0.001, d = 1.18) and HDD (pcorrected = 0.00009, d = 1.30). Post hoc analyses revealed that doxazosin significantly reduced alcohol drinking in AD patients with high FHDA and by contrast increased drinking in those with low FHDA. Doxazosin may be effective selectively in AD patients with high FHDA. This study provides preliminary evidence for personalized medicine using α1 -blockade to treat AD. However, confirmatory studies are required.


Assuntos
Antagonistas de Receptores Adrenérgicos alfa 1/uso terapêutico , Alcoolismo/tratamento farmacológico , Doxazossina/uso terapêutico , Adulto , Método Duplo-Cego , Feminino , Humanos , Masculino , Índice de Gravidade de Doença , Fatores Sexuais , Resultado do Tratamento
16.
Addict Biol ; 21(1): 171-82, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25353306

RESUMO

Topiramate reduces drinking, but little is known about the mechanisms that precipitate this effect. This double-blind randomized placebo-controlled study assessed the putative mechanisms by which topiramate reduces alcohol use among 96 adult non-treatment-seeking heavy drinkers in a laboratory-based alcohol cue reactivity assessment and in the natural environment using ecological momentary assessment methods. Topiramate reduced the quantity of alcohol heavy drinkers consumed on drinking days and reduced craving while participants were drinking but did not affect craving outside of drinking episodes in either the laboratory or in the natural environment. Topiramate did not alter the stimulant or sedative effects of alcohol ingestion during the ascending limb of the blood alcohol curve. A direct test of putative mechanisms of action using multilevel structural equation mediation models showed that topiramate reduced drinking indirectly by blunting alcohol-induced craving. These findings provide the first real-time prospective evidence that topiramate reduces drinking by reducing alcohol's priming effects on craving and highlight the importance of craving as an important treatment target of pharmacotherapy for alcoholism.


Assuntos
Transtornos Relacionados ao Uso de Álcool/tratamento farmacológico , Anticonvulsivantes/uso terapêutico , Fissura , Sinais (Psicologia) , Frutose/análogos & derivados , Adulto , Consumo de Bebidas Alcoólicas/tratamento farmacológico , Consumo de Bebidas Alcoólicas/psicologia , Transtornos Relacionados ao Uso de Álcool/psicologia , Método Duplo-Cego , Feminino , Frutose/uso terapêutico , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multinível , Topiramato , Adulto Jovem
17.
Ann Surg ; 261(3): 473-9, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25243543

RESUMO

OBJECTIVE: This study aimed to determine the prognostic significance of extramural venous invasion (EMVI) after chemoradiotherapy (CRT) by both magnetic resonance imaging (MRI) (ymrEMVI) and histopathology (ypEMVI). BACKGROUND: EMVI is a prognostic factor in rectal cancer but whether this remains so after CRT preoperative is unknown. Histopathological definitions of EMVI are variable and lead to underreporting particularly after CRT. METHODS: All consecutive patients staged on initial MRI as EMVI-positive undergoing preoperative CRT and curative surgery between Jan 2006 and Jan 2012 were included. Posttreatment EMVI status (yEMVI) was reevaluated for both MRI and pathology. The primary endpoint of disease-free survival (DFS) for ymrEMVI and ypEMVI was calculated using the Kaplan-Meier product limit and compared with a Mantel-Cox log-rank test. A P < 0.05 was considered significant. Hazard ratios (HRs) for disease recurrence were generated using Cox proportional hazard regression for MRI and histopathology tumor characteristics. RESULTS: A total of 188 patients who had evidence of EMVI on initial baseline MRI staging were included. MRI detected significantly more patients with persistent EMVI than histopathology (53% vs 19%) but both were prognostic for worse survival-ymrEMVI (HR 1.97) and ypEMVI (HR 2.39). Patients with persistent ymrEMVI-positivity had significantly worse DFS at 3 years (42.7%) compared with ymrEMVI-negative tumors (79.8%); DFS for was 36.9% versus 65.9% positive and negative ypEMVI, respectively. CONCLUSIONS: Detection of EMVI post-CRT is prognostically significant whether detected by MRI or histopathology. EMVI status after treatment may be used to counsel patients regarding ongoing risks of metastatic disease, implications for surveillance, and systemic chemotherapy.


Assuntos
Quimiorradioterapia , Imageamento por Ressonância Magnética/métodos , Invasividade Neoplásica/patologia , Neoplasias Retais/patologia , Neoplasias Retais/terapia , Neoplasias Vasculares/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Resultado do Tratamento
18.
Alcohol Clin Exp Res ; 39(4): 594-602, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25833022

RESUMO

BACKGROUND: Preliminary basic and human studies suggest that the α2 -adrenergic antagonist idazoxan may represent a novel medication for alcohol dependence. The goal of this study was to evaluate the safety and tolerability of the co-administration of idazoxan with alcohol and explore whether pharmacokinetics (PK) and biobehavioral mechanisms of idazoxan may alter alcohol's effects. METHODS: This was a preliminary double-blind, single-dose, placebo-controlled, crossover, randomized human laboratory study. Ten social drinkers were dosed, in 2 different alcohol challenge studies (ACS), with a single oral dose of idazoxan (40 mg) or placebo, followed by a fixed alcohol dose 60 minutes later. Participants returned after a 1-week washout, and they were crossed over to the opposite medication condition. RESULTS: There were no significant differences in adverse events between idazoxan and placebo. Moreover, during the ACS paradigm, 40 mg idazoxan was well tolerated with no significant autonomic effects compared to placebo; idazoxan reduced the peak blood alcohol level (p < 0.01) and time to peak (p < 0.05) compared to placebo. A PK/pharmacodynamic model aligned the biobehavioral effects, demonstrating that the co-administration of 40 mg idazoxan with alcohol decreased alcohol-related stimulation (p < 0.05) and increased alcohol-related sedation (p < 0.05). CONCLUSIONS: This study supports the safety and tolerability of 40 mg idazoxan when co-administered with alcohol. Additionally, this study suggests that idazoxan may alter the biphasic effects of alcohol by decreasing stimulation and increasing sedation. These findings have implications for further investigation of using idazoxan as a probe to develop potential novel medications to treat alcoholic patients.


Assuntos
Intoxicação Alcoólica/diagnóstico , Etanol/farmacologia , Etanol/farmacocinética , Idazoxano/farmacologia , Antagonistas de Receptores Adrenérgicos alfa 2/efeitos adversos , Antagonistas de Receptores Adrenérgicos alfa 2/farmacologia , Adulto , Pressão Sanguínea/efeitos dos fármacos , Estudos Cross-Over , Método Duplo-Cego , Interações Medicamentosas , Feminino , Frequência Cardíaca/efeitos dos fármacos , Humanos , Idazoxano/efeitos adversos , Masculino , Adulto Jovem
19.
Alcohol Alcohol ; 50(1): 24-9, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25433251

RESUMO

AIMS: A few studies have suggested a relationship between thyroid hormones and alcohol dependence (AD) such as a blunted increase of thyroid stimulating hormone (TSH) in response to thyrotropin-releasing hormone (TRH), lower levels of circulating free triiodothyronine (fT3) and free thyroxine (fT4) levels and down regulation of the TRH receptors. The current study aimed to explore the relationship between the hormones of the thyroid axis and alcohol-seeking behaviors in a sample of alcohol-dependent patients. METHODS: Forty-two treatment-seeking alcohol-dependent individuals enrolled in a 12-week treatment study were considered. The Timeline Follow Back (TLFB) was used to assess the number of drinks consumed during the 12-week period. Blood levels of thyroid hormones (TSH, fT3 and fT4) were measured prior to and at the end of treatment. Questionnaires were administered to evaluate craving for alcohol [Penn Alcohol Craving Scale (PACS) and the Obsessive Compulsive Drinking Scale (OCDS) and its two subscales ODS for obsessions and CDS for compulsions] as well as anxiety [State and Trait Inventory (STAI)], depression [the Zung Self-Rating Depression Scale (Zung)] and aggression [the Aggressive Questionnaire (AQ)]. RESULTS: At baseline, we found significant positive correlations between fT3 and OCDS (r = 0.358, P = 0.029) and CDS (r = 0.405, P = 0.013) and negative correlations between TSH levels and STAI (r = -0.342, P = 0.031), and AQ (r = -0.35, P = 0.027). At the end of the 12-week study period, abstinent patients had a greater change in TSH than those who relapsed (-0.4 vs. -0.25, F(1,24) = 5.4, P = 0.029). CONCLUSION: If confirmed in larger samples, these findings could suggest that the thyroid axis might represent a biomarker of alcohol craving and drinking.


Assuntos
Consumo de Bebidas Alcoólicas/fisiopatologia , Fissura/fisiologia , Hormônios Tireóideos/fisiologia , Adolescente , Adulto , Abstinência de Álcool/estatística & dados numéricos , Consumo de Bebidas Alcoólicas/sangue , Consumo de Bebidas Alcoólicas/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Psicológicos , Inquéritos e Questionários , Hormônios Tireóideos/sangue , Tireotropina/sangue , Tireotropina/fisiologia , Tiroxina/sangue , Tiroxina/fisiologia , Tri-Iodotironina/sangue , Tri-Iodotironina/fisiologia , Adulto Jovem
20.
Alcohol Clin Exp Res ; 38(6): 1567-74, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24773166

RESUMO

BACKGROUND: One hypothesis suggests that the differential response to ondansetron- and serotonin-specific re-uptake inhibitors (SSRIs) may be due to a functional polymorphism of the 5'-HTTLPR promoter region in SLC6A4, the gene that codes for the serotonin transporter (5-HTT). The LL 5'-HTTLPR genotype is postulated to be specifically sensitive to the effects of ondansetron with SS/SL 5'-HTTLPR genotypes sensitive to SSRIs. This study tests this hypothesis by matching nontreatment-seeking alcohol-dependent (AD) individuals with LL genotype to ondansetron and SS/SL genotypes to the SSRI sertraline, and mismatching them assessing naturalistic and bar-laboratory alcohol drinking. METHODS: Seventy-seven AD individuals were randomized to 1 of 2 counterbalanced arms to receive sertraline 200 mg/d or ondansetron 0.5 mg/d for 3 weeks followed by an alcohol self-administration experiment (ASAE) and then received placebo for 3 weeks followed by a second ASAE. Individuals then received the alternate drug for 3 weeks followed by a third ASAE. Drinks per drinking day (DDD with drinks in standard drinking units) for 7 days prior to each ASAE and milliliters consumed during each ASAE were the primary outcomes. RESULTS: Fifty-five participants completed the study. The genotype × order interaction was significant, F(1, 47) = 8.42, p = 0.006, for DDD. Three analyses of covariance were conducted for DDD during the week before each ASAE. Ondansetron compared to sertraline resulted in a significant reduction in DDD during the week before the first, F(1, 47) = 7.64, p = 0.008, but not the third ASAE. There was no difference in milliliters consumed during each ASAE. CONCLUSIONS: This study modestly supports the hypothesis that ondansetron may reduce DDD in AD individuals with the LL genotype as measured naturalistically. By contrast, there was no support that ondansetron reduces drinking during the ASAEs or that sertraline reduces alcohol use in individuals who have SS/SL genotypes. We provide limited support that ondansetron may reduce drinking in nontreatment-seeking individuals with the LL genotype.


Assuntos
Consumo de Bebidas Alcoólicas/tratamento farmacológico , Alcoolismo/tratamento farmacológico , Ondansetron/uso terapêutico , Antagonistas da Serotonina/uso terapêutico , Proteínas da Membrana Plasmática de Transporte de Serotonina/genética , Adulto , Idoso , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Sertralina/uso terapêutico , Adulto Jovem
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA