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1.
Genet Med ; 19(3): 297-305, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27513191

RESUMO

BACKGROUND: Smith-Lemli-Opitz syndrome (SLOS) is a multiple malformation/cognitive impairment syndrome characterized by the accumulation of 7-dehydrocholesterol, a precursor sterol of cholesterol. Simvastatin, a 3-hydroxy-3-methylglutaryl-coenzyme A reductase inhibitor that crosses the blood-brain barrier, has been proposed for the treatment of SLOS based on in vitro and in vivo studies suggesting that simvastatin increases the expression of hypomorphic DHCR7 alleles. METHODS: Safety and efficacy of simvastatin therapy in 23 patients with mild to typical SLOS were evaluated in a randomized, double-blind, placebo-controlled trial. The crossover trial consisted of two 12-month treatment phases separated by a 2-month washout period. RESULTS: No safety issues were identified in this study. Plasma dehydrocholesterol concentrations decreased significantly: 8.9 ± 8.4% on placebo to 6.1 ± 5.5% on simvastatin (P < 0.005); we observed a trend toward decreased cerebrospinal fluid dehydrocholesterol concentrations. A significant improvement (P = 0.017, paired t-test) was observed on the irritability subscale of the Aberrant Behavior Checklist-C when subjects were taking simvastatin. CONCLUSION: This article reports what is, to our knowledge, the first randomized, placebo-controlled trial designed to test the safety and efficacy of simvastatin therapy in SLOS. Simvastatin seems to be relatively safe in patients with SLOS, improves the serum dehydrocholesterol-to-total sterol ratio, and significantly improves irritability symptoms in patients with mild to classic SLOS.Genet Med 19 3, 297-305.


Assuntos
Sinvastatina/uso terapêutico , Síndrome de Smith-Lemli-Opitz/tratamento farmacológico , Adolescente , Alelos , Criança , Pré-Escolar , Colesterol , Estudos Cross-Over , Desidrocolesteróis/sangue , Método Duplo-Cego , Feminino , Humanos , Masculino , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/líquido cefalorraquidiano , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/genética , Placebos , Sinvastatina/efeitos adversos , Síndrome de Smith-Lemli-Opitz/sangue , Síndrome de Smith-Lemli-Opitz/líquido cefalorraquidiano , Síndrome de Smith-Lemli-Opitz/genética
2.
Clin Trials ; 14(1): 59-66, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27885056

RESUMO

BACKGROUND: The use of data monitoring committees in the conduct of clinical trials has increased and evolved, but there is a lack of published information on when data monitoring committees are needed and utilized, the acceptable range of data monitoring committee practices, and appropriate qualifications of data monitoring committee members. METHODS: To gain a better understanding of data monitoring committee operations and areas for improvement, the Clinical Trials Transformation Initiative conducted a survey and set of focus groups. A total of 143 respondents completed the online survey: 76 data monitoring committee members, 52 sponsors involved with organization of data monitoring committees, and 15 statistical data analysis center representatives. There were 42 focus group participants, including data monitoring committee members; patients and/or patient advocate data monitoring committee members; institutional review board and US Food and Drug Administration representatives; industry, government, and non-profit sponsors; and statistical data analysis center representatives. RESULTS: Participants indicated that the primary responsibility of a data monitoring committee is to be an independent advisory body representing the interests of trial participants by assessing the risk and benefit ratio in ongoing trials. They noted that data monitoring committees must have access to unmasked data in order to perform this role. No clear consensus emerged regarding specific criteria for requiring a data monitoring committee for a given trial, and some participants felt data monitoring committees may be overused. Respondents offered suggestions for the data monitoring committee charter and communications with sponsors, institutional review boards, and regulators. Overall, data monitoring committee members reported that they are able to function independently and their recommendations are almost always accepted by the sponsor. Participants indicated that there are no standards or guidelines pertaining to qualifications of data monitoring committee members. Furthermore, only 8% (6/72) of data monitoring committee member survey respondents received any formal training, and 94% (68/72) were not aware of any training programs. CONCLUSION: Findings from the survey and focus groups provide a better understanding of contemporary data monitoring committee operations and insights regarding challenges and best practices. Overall, it was clear that increased training will be needed to prepare the next generation of qualified data monitoring committee members to meet the growing demand. These findings can be used by Clinical Trials Transformation Initiative and others to develop recommendations and tools to improve data monitoring committee operations and the overall quality of trial oversight.


Assuntos
Comitês de Monitoramento de Dados de Ensaios Clínicos , Ensaios Clínicos como Assunto , Interpretação Estatística de Dados , Comitês de Ética em Pesquisa , Grupos Focais , Humanos , Futilidade Médica , Segurança do Paciente , Papel Profissional , Inquéritos e Questionários , Estados Unidos , United States Food and Drug Administration
3.
Clin Trials ; 14(4): 342-348, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28503947

RESUMO

Background/aims Use of data monitoring committees to oversee clinical trials was first proposed nearly 50 years ago. Since then, data monitoring committee use in clinical trials has increased and evolved. Nonetheless, there are no well-defined criteria for determining the need for a data monitoring committee, and considerable variability exists in data monitoring committee composition and conduct. To understand and describe the role and function of data monitoring committees, and establish best practices for data monitoring committee trial oversight, the Clinical Trials Transformation Initiative-a public-private partnership to improve clinical trials-launched a multi-stakeholder project. Methods The data monitoring committee project team included 16 individuals charged with (1) clarifying the purpose of data monitoring committees, (2) identifying best practices for independent data monitoring committee conduct, (3) describing effective communication practices, and (4) developing strategies for training data monitoring committee members. Evidence gathering included a survey, a series of focus group discussions, and a 2-day expert meeting aimed at achieving consensus opinions that form the foundation of our data monitoring committee recommendations. Results We define the role of the data monitoring committee as an advisor to the research sponsor on whether to continue, modify, or terminate a trial based on periodic assessment of trial data. Data monitoring committees should remain independent from the sponsor and be composed of members with no relevant conflicts of interest. Representation on a data monitoring committee generally should include at least one clinician with expertise in the therapeutic area being studied, a biostatistician, and a designated chairperson who has experience with clinical trials and data monitoring. Data monitoring committee meetings are held periodically to evaluate the unmasked data from ongoing trials, but the content and conduct of meetings may vary depending on specific goals or topics for deliberation. To guide data monitoring committee conduct and communication plans, a charter consistent with the protocol's research design and statistical analysis plan should be developed and agreed upon by the sponsor and the data monitoring committee prior to patient enrollment. We recommend concise and flexible charters that explain roles, responsibilities, operational issues, and how data monitoring committee recommendations are generated and communicated. The demand for data monitoring committee members appears to exceed the current pool of qualified individuals. To prepare a new generation of trained data monitoring committee members, we encourage a combination of didactic educational programs, practical experience, and skill development through apprenticeships and mentoring by experienced data monitoring committee members. Conclusion Our recommendations address data monitoring committee use, conduct, communication practices, and member preparation and training. Furthermore recommendations form the foundation for ongoing efforts to improve clinical trial oversight and enhance the safety and integrity of clinical research. These recommendations serve as a call to action for implementation of best practices that benefit study participants, study sponsors, and society.


Assuntos
Comitês de Monitoramento de Dados de Ensaios Clínicos/organização & administração , Ensaios Clínicos como Assunto , Interpretação Estatística de Dados , Comitês de Monitoramento de Dados de Ensaios Clínicos/normas , Consenso , Humanos , Comunicação Interdisciplinar , Melhoria de Qualidade , Projetos de Pesquisa
4.
Clin Trials ; 14(2): 115-123, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28359194

RESUMO

BACKGROUND AND PURPOSE: Data monitoring committees are responsible for safeguarding the interests of study participants and assuring the integrity and credibility of clinical trials. The independence of data monitoring committees from sponsors and investigators is essential in achieving this mission. Creative approaches are needed to address ongoing and emerging challenges that potentially threaten data monitoring committees' independence and effectiveness. METHODS: An expert panel of representatives from academia, industry and government sponsors, and regulatory agencies discussed these challenges and proposed best practices and operating principles for effective functioning of contemporary data monitoring committees. RESULTS AND CONCLUSIONS: Prospective data monitoring committee members need better training. Options could include didactic instruction as well as apprenticeships to provide real-world experience. Data monitoring committee members should be protected against legal liability arising from their service. While avoiding breaches in confidentiality of interim data remains a high priority, data monitoring committees should have access to unblinded efficacy and safety data throughout the trial to enable informed judgments about risks and benefits. Because overly rigid procedures can compromise their independence, data monitoring committees should have the flexibility necessary to best fulfill their responsibilities. Data monitoring committee charters should articulate principles that guide the data monitoring committee process rather than list a rigid set of requirements. Data monitoring committees should develop their recommendations by consensus rather than through voting processes. The format for the meetings of the data monitoring committee should maintain the committee's independence and clearly establish the leadership of the data monitoring committee chair. The independent statistical group at the Statistical Data Analysis Center should have sufficient depth of knowledge about the study at hand and experience with trials in general to ensure that the data monitoring committee has access to timely, reliable, and readily interpretable insights about emerging evidence in the clinical trial. Contracts engaging data monitoring committee members for industry-sponsored trials should have language customized to the unique responsibilities of data monitoring committee members rather than use language appropriate to consultants for product development. Regulatory scientists would benefit from experiencing data monitoring committee service that does not conflict with their regulatory responsibilities.


Assuntos
Comitês de Monitoramento de Dados de Ensaios Clínicos , Guias de Prática Clínica como Assunto , Confidencialidade , Humanos , Seguro
5.
Cochrane Database Syst Rev ; 6: CD004637, 2017 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-28625021

RESUMO

BACKGROUND: Elective hysterectomy is commonly performed for benign gynaecological conditions. Hysterectomy can be performed abdominally, laparoscopically, or vaginally, with or without laparoscopic assistance. Antibiotic prophylaxis consists of administration of antibiotics to reduce the rate of postoperative infection, which otherwise affects 40%-50% of women after vaginal hysterectomy, and more than 20% after abdominal hysterectomy. No Cochrane review has systematically assessed evidence on this topic. OBJECTIVES: To determine the effectiveness and safety of antibiotic prophylaxis in women undergoing elective hysterectomy. SEARCH METHODS: We searched electronic databases to November 2016 (including the Cochrane Gynaecology and Fertility Group Specialised Register, the Cochrane Central Register of Studies (CRSO), MEDLINE, Embase, PsycINFO, and the Cumulative Index to Nursing and Allied Health Literature (CINAHL), as well as clinical trials registers, conference abstracts, and reference lists of relevant articles. SELECTION CRITERIA: All randomised controlled trials (RCTs) comparing use of antibiotics versus placebo or other antibiotics as prophylaxis in women undergoing elective hysterectomy. DATA COLLECTION AND ANALYSIS: We used Cochrane standard methodological procedures. MAIN RESULTS: We included in this review 37 RCTs, which performed 20 comparisons of various antibiotics versus placebo and versus one another (6079 women). The quality of the evidence ranged from very low to moderate. The main limitations of study findings were risk of bias due to poor reporting of methods, imprecision due to small samples and low event rates, and inadequate reporting of adverse effects. Any antibiotic versus placebo Vaginal hysterectomyModerate-quality evidence shows that women who received antibiotic prophylaxis had fewer total postoperative infections (risk ratio (RR) 0.28, 95% confidence interval (CI) 0.19 to 0.40; five RCTs, N = 610; I2 = 85%), less urinary tract infection (UTI) (RR 0.58, 95% CI 0.43 to 0.77; eight RCTs, N = 1790; I2 = 44%), fewer pelvic infections (RR 0.28, 95% CI 0.20 to 0.39; 11 RCTs, N = 2010; I2 = 57%), and fewer postoperative fevers (RR 0.43, 95% CI 0.34 to 0.54; nine RCTs, N = 1879; I2 = 48%) than women who did not receive such prophylaxis. This suggests that antibiotic prophylaxis reduces the average risk of postoperative infection from about 34% to 7% to 14%. Whether this treatment has led to differences in rates of other serious infection remains unclear (RR 0.20, 95% CI 0.01 to 4.10; one RCT, N = 146; very low-quality evidence).Data were insufficient for comparison of adverse effects. Abdominal hysterectomyWomen who received antibiotic prophylaxis of any class had fewer total postoperative infections (RR 0.16, 95% CI 0.06 to 0.38; one RCT, N = 345; low-quality evidence), abdominal wound infections (RR 0.64, 95% CI 0.45 to 0.92; 11 RCTs, N = 2434; I2 = 0%; moderate-quality evidence), UTIs (RR 0.39, 95% CI 0.29 to 0.51; 11 RCTs, N = 2547; I2 = 26%; moderate-quality evidence), pelvic infections (RR 0.50, 95% CI 0.35 to 0.71; 11 RCTs, N = 1883; I2 = 11%; moderate-quality evidence), and postoperative fevers (RR 0.60, 95% CI 0.51 to 0.70; 11 RCTs, N = 2581; I2 = 51%; moderate-quality evidence) than women who did not receive prophylaxis, suggesting that antibiotic prophylaxis reduces the average risk of postoperative infection from about 16% to 1% to 6%. Whether this treatment has led to differences in rates of other serious infection remains unclear (RR 0.44, 95% CI 0.12 to 1.69; two RCTs, N = 476; I2 = 29%; very low-quality evidence).It is unclear whether rates of adverse effects differed between groups (RR 1.80, 95% CI 0.62 to 5.18; two RCTs, N = 430; I2 = 0%; very low-quality evidence). Head-to-head comparisons between antibiotics Vaginal hysterectomyWe identified four comparisons: cephalosporin versus penicillin (two RCTs, N = 470), cephalosporin versus tetracycline (one RCT, N = 51), antiprotozoal versus lincosamide (one RCT, N = 80), and cephalosporin versus antiprotozoal (one RCT, N = 78). Data show no evidence of differences between groups for any of the primary outcomes, except that fewer cases of total postoperative infection and postoperative fever were reported in women who received cephalosporin than in those who received antiprotozoal.Only one comparison (cephalosporin vs penicillin; two RCTs, N = 451) yielded data on adverse effects and showed no differences between groups. Abdominal hysterectomyWe identified only one comparison: cephalosporin versus penicillin (N = 220). Data show no evidence of differences between groups for any of the primary outcomes. Adverse effects were not reported. Combined antibiotics versus single antibiotics Vaginal hysterectomyWe identified three comparisons: cephalosporin plus antiprotozoal versus cephalosporin (one RCT, N = 78), cephalosporin plus antiprotozoal versus antiprotozoal (one RCT, N = 78), and penicillin plus antiprotozoal versus penicillin (one RCT, N = 230). Data were unavailable for most outcomes, including adverse effects. We found no evidence of differences between groups, except that fewer women receiving cephalosporin with antiprotozoal received a diagnosis of total postoperative infection, UTI, or postoperative fever compared with women receiving antiprotozoal. Abdominal hysterectomyWe identified one comparison (penicillin plus antiprotozoal vs penicillin only; one RCT, N = 230). Whether differences between groups occurred was unclear. Adverse effects were not reported. Comparison of cephalosporins in different regimensSingle small trials addressed dose comparisons and provided no data for most outcomes, including adverse effects. Whether differences between groups occurred was unclear. No trials compared route of administration.The quality of evidence for all head-to-head and dose comparisons was very low owing to very serious imprecision and serious risk of bias related to poor reporting of methods. AUTHORS' CONCLUSIONS: Antibiotic prophylaxis appears to be effective in preventing postoperative infection in women undergoing elective vaginal or abdominal hysterectomy, regardless of the dose regimen. However, evidence is insufficient to show whether use of prophylactic antibiotics influences rates of adverse effects. Similarly, evidence is insufficient to show which (if any) individual antibiotic, dose regimen, or route of administration is safest and most effective. The most recent studies included in this review were 14 years old at the time of our search. Thus findings from included studies may not reflect current practice in perioperative and postoperative care and may not show locoregional antimicrobial resistance patterns.


Assuntos
Antibacterianos/uso terapêutico , Antibioticoprofilaxia , Infecções Bacterianas/prevenção & controle , Procedimentos Cirúrgicos Eletivos/efeitos adversos , Histerectomia/efeitos adversos , Complicações Pós-Operatórias/prevenção & controle , Antiprotozoários/uso terapêutico , Cefalosporinas/uso terapêutico , Febre/epidemiologia , Humanos , Histerectomia/métodos , Lincosamidas/uso terapêutico , Pelve , Penicilinas/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto , Sulfonamidas/uso terapêutico , Infecções Urinárias/epidemiologia , Infecções Urinárias/prevenção & controle
8.
Clin Endocrinol (Oxf) ; 72(4): 441-7, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19486026

RESUMO

OBJECTIVE: Existing glucocorticoid treatment for congenital adrenal hyperplasia (CAH) is suboptimal and nonphysiological. We compared hormonal profiles during therapy with a new modified-release hydrocortisone (MR-HC), Chronocort, to conventional hydrocortisone (HC), Cortef, in patients with CAH. DESIGN AND PATIENTS: We conducted a Phase 2, open-label, crossover pharmacokinetic and pharmacodynamic study in 14 patients (out of whom seven were male subjects, age ranging from 17 to 55) with classic 21-hydroxylase deficiency. One week of thrice daily HC (10, 5 and 15 mg) was followed by 1 month of once daily MR-HC (30 mg at 22:00 hours). Twenty four-hour sampling of cortisol, 17-hydroxyprogesterone (17-OHP), androstenedione, and ACTH was performed at steady state. MEASUREMENTS: The primary outcome measures were 8- and 24-h area under the curve (AUC) hormones and 08:00 hours 17-OHP. RESULTS: Hydrocortisone therapy resulted in three cortisol peaks. A single cortisol peak occurred at approximately 06:00 hours on MR-HC. MR-HC resulted in significantly (P < 0.001) lower 24-h afternoon (12:00 to 20:00 hours), and night-time (20:00 to 04:00 hours) cortisol as compared with HC. From 04:00 to 12:00 hours, when physiological cortisol is highest, cortisol was higher on MR-HC than HC (P < 0.001). Patients on MR-HC had significantly (P < 0.05) higher afternoon (12:00 to 20:00 hours) 17-OHP, androstenedione and ACTH, but significantly (P = 0.025) lower 08:00 hours 17-OHP. No serious adverse events occurred. CONCLUSIONS: Modified-release hydrocortisone represents a promising new treatment for CAH. Overnight adrenal androgens were well-controlled, but rose in the afternoon with once-daily dosing suggesting that a morning dose of glucocorticoid is needed. Further studies are needed to determine the optimal dosing regimen and long-term clinical outcome.


Assuntos
Hiperplasia Suprarrenal Congênita/tratamento farmacológico , Hidrocortisona/administração & dosagem , Adolescente , Adulto , Área Sob a Curva , Ritmo Circadiano , Estudos Cross-Over , Preparações de Ação Retardada/farmacocinética , Preparações de Ação Retardada/uso terapêutico , Esquema de Medicação , Feminino , Humanos , Hidrocortisona/farmacocinética , Masculino , Pessoa de Meia-Idade
9.
Ann Intern Med ; 150(12): 821-9, W145-6, 2009 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-19528561

RESUMO

BACKGROUND: Some data suggest that increasing calcium intake may help prevent weight gain. OBJECTIVE: To test the hypothesis that calcium supplementation can prevent weight gain in persons who are overweight or obese. DESIGN: Randomized, placebo-controlled trial. Randomization was computer-generated, and allocation was assigned by pharmacy personnel who prepared intervention and placebo capsules. Participants, providers, and those who assessed outcomes were blinded to study group assignment. SETTING: Single research center. PARTICIPANTS: 340 overweight (body mass index [BMI], 25 to <30 kg/m(2)) and obese (BMI > or =30 kg/m(2)) adults (mean age, 38.8 years [SD, 10.5]). INTERVENTION: Calcium carbonate (elemental calcium, 1500 mg/d) (n = 170) or placebo (n = 170) with meals for 2 years. MEASUREMENTS: Changes in body weight and fat mass (primary outcomes). RESULTS: Seventy-five percent of participants completed the trial (78% received calcium; 73% received placebo). There were no statistically or clinically significant differences between the calcium and placebo groups in change in body weight (difference, 0.02 kg [95% CI, -1.64 to 1.69 kg]; P = 0.98), BMI (difference, 0.32 kg/m(2) [CI, -0.41 to 1.02 kg/m(2)]; P = 0.39), or body fat mass (difference, 0.39 kg [CI, -1.04 to 1.92 kg]; P = 0.55). Parathyroid hormone concentrations decreased in the calcium group compared with the placebo group (difference, -0.71 pmol/L [CI, -1.28 to -0.13 pmol/L]). LIMITATION: The study took place at a research center, and its sample was mostly women. CONCLUSION: Dietary supplementation with elemental calcium, 1500 mg/d, for 2 years had no statistically or clinically significant effects on weight in overweight and obese adults. Calcium supplementation is unlikely to have clinically significant efficacy as a preventive measure against weight gain in such patients.


Assuntos
Carbonato de Cálcio/administração & dosagem , Cálcio da Dieta/administração & dosagem , Suplementos Nutricionais , Obesidade/dietoterapia , Sobrepeso/dietoterapia , Adiposidade , Adolescente , Adulto , Idoso , Índice de Massa Corporal , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Cooperação do Paciente , Sensibilidade e Especificidade , Inquéritos e Questionários , Redução de Peso , Adulto Jovem
10.
Ann N Y Acad Sci ; 1135: 43-51, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18574207

RESUMO

Menstruation is the cyclic, orderly sloughing of the uterine lining on account of the interactions of hormones produced by the hypothalamus, pituitary, and ovaries. There is a tendency among parents and clinicians to view oligo-amenorrhea as a normal variant in the teen years. In fact, the 95th percentile for the time interval between cycles is 90 days. Thus, it is abnormal for an adolescent to be amenorrheic for greater than 3 months, even in the early gynecologic years. Identification of abnormal menstrual patterns throughout adolescence may permit early identification of potential health concerns for adulthood. Few problems in gynecologic endocrinology are as complex or challenging to the clinician as amenorrhea. However, thorough evaluation of menstrual cycle disorders in adolescence provides a window of opportunity for early diagnosis and treatment of conditions affecting the hypothalamic-pituitary-ovarian (HPO) axis. Here we discuss a systematic approach to the evaluation and treatment of amenorrhea in adolescents who do not have androgen excess. There is strong evidence that estrogen deficiency is a risk factor for later development of osteoporosis and hip fracture. Delay in the evaluation and treatment of disordered menses in some cases may contribute to reduced bone density. Both patients and clinicians need to view the ovary as an important endocrine organ that helps maintain health, especially bone health.


Assuntos
Amenorreia/diagnóstico , Amenorreia/tratamento farmacológico , Saúde , Ciclo Menstrual , Adolescente , Amenorreia/etiologia , Biomarcadores , Densidade Óssea , Estrogênios/deficiência , Feminino , Terapia de Reposição Hormonal , Humanos , Sistema Hipotálamo-Hipofisário/fisiologia , Sistema Hipotálamo-Hipofisário/fisiopatologia , Ovário/fisiologia , Ovário/fisiopatologia , Fatores de Risco
11.
Toxicology ; 248(1): 8-17, 2008 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-18423834

RESUMO

Non-clinical studies were conducted to evaluate the toxicity of Antalarmin, a corticotropin-releasing hormone type 1 receptor antagonist being developed for therapy of stress-related pathologies. Antalarmin was not genotoxic in bacterial mutagenesis assays, mammalian cell mutagenesis assays, or in vivo DNA damage assays. In a 14-day range-finding study in rats, Antalarmin doses >or=500 mg/kg/day (3,000 mg/m(2)/day) induced mortality. In a 90-day toxicity study in rats, no gross toxicity was seen at doses of 30, 100, or 300 mg/kg/day (180, 600, or 1,800 mg/m(2)/day, respectively). Antalarmin (300 mg/kg/day) induced mild anemia, increases in serum gamma-glutamyl transferase activity, and microscopic hepatic pathology (bile duct hyperplasia and epithelial necrosis, periportal inflammation). Microscopic renal changes (cortical necrosis, inflammation, hypertrophy, nephropathy) were observed in rats at all Antalarmin doses. In a 14-day range-finding study in dogs, Antalarmin doses >or=50mg/kg/day (1,000 mg/m(2)/day) induced repeated emesis and bone marrow suppression. In a 90-day toxicity study in dogs, Antalarmin (4, 8, or 16 mg/kg/day (80, 160, or 320 mg/m(2)/day, respectively)) induced bone marrow and lymphoid depletion, but no gross toxicity. Comparative in vitro studies using rat, dog, and human neutrophil progenitors demonstrated that canine bone marrow cells are highly sensitive to Antalarmin cytotoxicity, while rat and human bone marrow cells are relatively insensitive. As such, the bone marrow toxicity observed in dogs is considered likely to over-predict Antalarmin toxicity in humans. The hepatic and renal toxicities seen in rats exposed to Antalarmin identify those tissues as the most likely targets for Antalarmin toxicity in humans.


Assuntos
Pirimidinas/toxicidade , Pirróis/toxicidade , Receptores de Hormônio Liberador da Corticotropina/antagonistas & inibidores , Animais , Células da Medula Óssea/efeitos dos fármacos , Células da Medula Óssea/patologia , Linhagem Celular Tumoral , Ensaio de Unidades Formadoras de Colônias , Cães , Feminino , Humanos , Rim/efeitos dos fármacos , Rim/patologia , Fígado/efeitos dos fármacos , Fígado/patologia , Masculino , Camundongos , Testes de Mutagenicidade , Nível de Efeito Adverso não Observado , Ratos , Ratos Endogâmicos F344 , Salmonella typhimurium/efeitos dos fármacos , Salmonella typhimurium/genética , Vômito/induzido quimicamente
12.
J Am Diet Assoc ; 108(1): 145-8, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18156002

RESUMO

Hypoferremia is more prevalent in obese than nonobese adults, but the reason for this phenomenon is unknown. To elucidate the role dietary factors play in obesity-related hypoferremia, the intake of heme and nonheme iron and the intake of other dietary factors known to affect iron absorption were compared cross-sectionally from April 2002 to December 2003 in a convenience sample of 207 obese and 177 nonobese adults. Subjects completed 7-day food records, underwent phlebotomy for serum iron measurement, and had body composition assessed by dual-energy x-ray absorptiometry, during a 21-month period. Data were analyzed by analysis of covariance and multiple linear regression. Serum iron (mean+/-standard deviation) was significantly lower in obese than nonobese individuals (72.0+/-61.7 vs 85.3+/-58.1 microg/dL [12.888+/-11.0443 vs 15.2687+/-10.3999 micromol/L]; P<0.001). The obese cohort reported consuming more animal protein (63.6+/-34.5 vs 55.7+/-32.5 g/day; P<0.001) and more heme iron (3.6+/-2.8 vs 2.7+/-2.6 mg/day; P<0.001). Groups did not differ, however, in total daily iron consumption, including supplements. Obese subjects reported consuming less vitamin C (77.2+/-94.9 vs 91.8+/-89.5 mg/day; P=0.01), which may increase absorption of nonheme iron, and less calcium (766.2+/-665.0 vs 849.0+/-627.2 mg/day; P=0.038), which may decrease nonheme iron absorption, than nonobese subjects. Groups did not significantly differ in intake of other dietary factors that can impact absorption of iron, including phytic acid, oxalic acid, eggs, coffee, tea, zinc, vegetable protein, or copper. After accounting for demographic covariates and dietary factors expected to affect iron absorption, fat mass (P=0.007) remained a statistically significant negative predictor of serum iron. This cross-sectional, exploratory study suggests that obesity-related hypoferremia is not associated with differences in reported intake of heme and nonheme iron or intake of dietary factors that can affect iron absorption.


Assuntos
Ácido Ascórbico/administração & dosagem , Dieta , Deficiências de Ferro , Ferro da Dieta/farmacocinética , Ferro/sangue , Obesidade/sangue , Absorciometria de Fóton , Tecido Adiposo/metabolismo , Adulto , Antioxidantes/administração & dosagem , Antioxidantes/metabolismo , Ácido Ascórbico/farmacologia , Composição Corporal/fisiologia , Cálcio da Dieta/administração & dosagem , Cálcio da Dieta/farmacologia , Estudos Transversais , Registros de Dieta , Feminino , Humanos , Absorção Intestinal/efeitos dos fármacos , Absorção Intestinal/fisiologia , Ferro da Dieta/administração & dosagem , Ferro da Dieta/metabolismo , Masculino , Avaliação Nutricional , Obesidade/metabolismo
13.
Arch Intern Med ; 167(21): 2329-36, 2007 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-18039992

RESUMO

BACKGROUND: An increased prevalence of low bone mineral density (BMD) has been reported in patients with major depressive disorder (MDD), mostly women. METHODS: Study recruitment was conducted from July 1, 2001, to February 29, 2003. We report baseline BMD measurements in 89 premenopausal women with MDD and 44 healthy control women enrolled in a prospective study of bone turnover. The BMD was measured by dual-energy x-ray absorptiometry at the spine, hip, and forearm. Mean hourly levels of plasma 24-hour cytokines, 24-hour urinary free cortisol, and catecholamine excretion were measured in a subset of women. We defined MDD according to the Diagnostic and Statistical Manual of Mental Disorders (Fourth Edition). RESULTS: The prevalence of low BMD, defined as a T score of less than -1, was greater in women with MDD vs controls at the femoral neck (17% vs 2%; P = .02) and total hip (15% vs 2%; P = .03) and tended to be greater at the lumbar spine (20% vs 9%; P = .14). The mean +/- SD BMD, expressed as grams per square centimeters, was lower in women with MDD at the femoral neck (0.849 +/- 0.121 vs 0.866 +/- 0.094; P = .05) and at the lumbar spine (1.024 +/- 0.117 vs 1.043 +/- 0.092; P = .05) and tended to be lower at the radius (0.696 +/- 0.049 vs 0.710 +/- 0.055; P = .07). Women with MDD had increased mean levels of 24-hour proinflammatory cytokines and decreased levels of anti-inflammatory cytokines. CONCLUSIONS: Low BMD is more prevalent in premenopausal women with MDD. The BMD deficits are of clinical significance and comparable in magnitude to those resulting from established risk factors for osteoporosis, such as smoking and reduced calcium intake. The possible contribution of immune or inflammatory imbalance to low BMD in premenopausal women with MDD remains to be clarified.


Assuntos
Densidade Óssea , Transtorno Depressivo/fisiopatologia , Pré-Menopausa/fisiologia , Absorciometria de Fóton , Adulto , Doenças Ósseas/etiologia , Doenças Ósseas/fisiopatologia , Catecolaminas/urina , Transtorno Depressivo/complicações , Transtorno Depressivo/diagnóstico , Feminino , Humanos , Hidrocortisona/urina , Interleucina-10/sangue , Interleucina-13/sangue , Interleucina-1beta/sangue , Interleucina-2/sangue , Interleucina-6/sangue , Pré-Menopausa/sangue , Pré-Menopausa/urina , Estudos Prospectivos , Fator de Necrose Tumoral alfa/sangue
14.
J Clin Pharmacol ; 57(2): 219-229, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27407018

RESUMO

Steady-state population pharmacokinetics of a noncommercial immediate-release metformin (hydrochloride) drug product were characterized in 28 severely obese children with insulin resistance. The concentration-time profiles with double peaks were well described by a 1-compartment model with 2 absorption sites. Mean population apparent clearance (CL/F) was 68.1 L/h, and mean apparent volume of distribution (V/F) was 28.8 L. Body weight was a covariate of CL/F and V/F. Estimated glomerular filtration rate was a significant covariate of CL/F (P < .001). SLC22A1 genotype did not significantly affect metformin pharmacokinetics. The response to 6 months of metformin treatment (HbA1c , homeostasis model assessment for insulin resistance, fasting insulin, and glucose changes) did not differ between SLC22A1 wild-type subjects and carriers of presumably low-activity SLC22A1 alleles. However, SLC22A1 variant carriers had smaller reductions in percentage of total trunk fat after metformin therapy, although the percentage reduction in trunk fat was small. The median % change in trunk fat was -2.20% (-9.00% to 0.900%) and -1.20% (-2.40% to 7.30%) for the SLC22A1 wild-type subjects and variant carriers, respectively. Future study is needed to evaluate the effects of SLC22A1 polymorphisms on metformin-mediated weight reduction in obese children.


Assuntos
Adiposidade/efeitos dos fármacos , Adiposidade/genética , Hipoglicemiantes/farmacologia , Hipoglicemiantes/farmacocinética , Resistência à Insulina/genética , Metformina/farmacologia , Metformina/farmacocinética , Obesidade/tratamento farmacológico , Obesidade/genética , Fator 1 de Transcrição de Octâmero/genética , Fator 1 de Transcrição de Octâmero/metabolismo , Peso Corporal , Criança , Método Duplo-Cego , Feminino , Genótipo , Taxa de Filtração Glomerular , Humanos , Masculino , Polimorfismo Genético/genética , Redução de Peso/efeitos dos fármacos
15.
J Clin Pharmacol ; 46(5): 515-26, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16638735

RESUMO

The influence of diet and genetics was investigated in a healthy white person who had distinctly low methylprednisolone clearance. Pharmacokinetic and pharmacodynamic parameter values were similar on 2 occasions during the consumption of a low-carbohydrate diet and a Weight Watchers diet, indicating that the decreased clearance was unlikely attributable to a change in diet composition. Although the subject was found to be homozygous for CYP3A5*3, genetic findings were not significant for a number of other CYP3A4 and CYP3A5 allelic variants. Because of the high prevalence of CYP3A5*3/*3 in whites and because 5 of 7 white control subjects are also homozygous for CYP3A5*3, this genotype cannot fully explain the reduced metabolism of the drug. Other genetic or contributing factors might have been involved. New polymerase chain reaction-based genotyping methods for functionally defective CYP3A5*6, *8, *9, and *10 alleles were developed in this study. These assays will be useful for CYP3A5 genotype analysis in future clinical studies.


Assuntos
Metilprednisolona/farmacocinética , Adulto , Alelos , Citocromo P-450 CYP3A , Sistema Enzimático do Citocromo P-450/genética , Dieta , Histamina/sangue , Humanos , Hidrocortisona/sangue , Masculino , Taxa de Depuração Metabólica , Metilprednisolona/sangue , Metilprednisolona/farmacologia , Polimorfismo de Nucleotídeo Único
16.
Semin Reprod Med ; 24(2): 106-14, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16633984

RESUMO

Testosterone therapy for postmenopausal women and women with surgical menopause, albeit controversial, is becoming more widespread. However, only limited data are available to support its use in premenopausal women. Androgens have important biological roles in young women, influencing bone and muscle mass, mood and well-being, and libido. Pathophysiological states affecting ovarian and adrenal function or both may result in androgen deficiency in premenopausal women. Young women with hypothalamic amenorrhea, premature ovarian failure, oophorectomy, premenstrual syndrome, acquired immunodeficiency wasting syndrome, adrenal insufficiency, and hypopituitarism may have testosterone deficiency. Young women with loss of libido may also have testosterone deficiency. Medications that may lead to testosterone insufficiency include oral estrogen, oral contraceptives, and corticosteroids. Testosterone deficiency in young women may be underdiagnosed because the symptoms generally are nonspecific and the measurement of total and free testosterone is inaccurate with commonly used techniques. Only a few studies investigating the effects of testosterone therapy have been performed thus far in premenopausal women. Long-term trials evaluating safety and effectiveness of testosterone therapy in premenopausal women are lacking. Common adverse effects include hirsutism and acne, which reverse with discontinuation of treatment. The availability of testosterone regimens specifically designed for women is expected to help maintain testosterone levels within the normal range and clarify whether the apparent beneficial effects of testosterone therapy are physiological or pharmacological.


Assuntos
Pré-Menopausa , Testosterona/uso terapêutico , Adulto , Androgênios/deficiência , Androgênios/fisiologia , Osso e Ossos/fisiologia , Neoplasias da Mama , Doenças Cardiovasculares , Neoplasias do Endométrio , Feminino , Humanos , Libido , Pessoa de Meia-Idade , Músculo Esquelético/fisiologia , Fatores de Risco , Comportamento Sexual/fisiologia , Testosterona/efeitos adversos
17.
Health Qual Life Outcomes ; 4: 2, 2006 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-16420706

RESUMO

BACKGROUND: Whereas it is established that organic pain may induce depression, it is unclear whether pain is more common in healthy subjects with depression. We assessed the prevalence of pain in premenopausal women with major depression (MDD). Subjects were 21- to 45-year-old premenopausal women with MDD (N = 70; age: 35.4 +/- 6.6; mean +/- SD) and healthy matched controls (N = 36; age 35.4 +/- 6.4) participating in a study of bone turnover, the P.O.W.E.R. (Premenopausal, Osteopenia/Osteoporosis, Women, Alendronate, Depression) Study. METHODS: Patients received a clinical assessment by a pain specialist, which included the administration of two standardized forms for pain, the Brief Pain Inventory - Short Form, and the Initial Pain Assessment Tool, and two scales of everyday stressors, the Hassles and Uplifts Scales. In addition, a quality-of-life instrument, the SF-36, was used. The diagnosis of MDD was established by a semi-structured interview, according to the DSM-IV criteria. Substance P (SP) and calcitonin-gene-related-peptide (CGRP), neuropeptides which are known mediators of pain, were measured every hour for 24 h in a subgroup of patients (N = 17) and controls (N = 14). RESULTS: Approximately one-half of the women with depression reported pain of mild intensity. Pain intensity was significantly correlated with the severity of depression (r2 = 0.076; P = 0.04) and tended to be correlated with the severity of anxiety, (r2 = 0.065; P = 0.07), and the number of depressive episodes (r2 = 0.072; P = 0.09). Women with MDD complained of fatigue, insomnia, and memory problems and experienced everyday negative stressors more frequently than controls. Quality of life was decreased in women with depression, as indicated by lower scores in the emotional and social well-being domains of the SF-36. SP (P < 0.0003) and CGRP (P < 0.0001) were higher in depressed subjects. CONCLUSION: Women with depression experienced pain more frequently than controls, had a lower quality of life, and complained more of daily stressors. Assessment of pain may be important in the clinical evaluation of women with MDD. SP and CGRP may be useful biological markers in women with MDD.


Assuntos
Transtorno Depressivo Maior/complicações , Dor/complicações , Pré-Menopausa/psicologia , Qualidade de Vida , Adulto , Alendronato/uso terapêutico , Densidade Óssea/efeitos dos fármacos , Conservadores da Densidade Óssea/uso terapêutico , Peptídeo Relacionado com Gene de Calcitonina/sangue , Estudos de Casos e Controles , Transtorno Depressivo Maior/sangue , Feminino , Humanos , Estudos Longitudinais , Pessoa de Meia-Idade , Medição da Dor , Estresse Psicológico/complicações , Substância P/sangue
18.
J Clin Endocrinol Metab ; 90(12): 6549-52, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16174721

RESUMO

CONTEXT: Evidence suggests that young women with spontaneous premature ovarian failure (sPOF) have significantly lower androgen levels than age-matched regularly menstruating women. OBJECTIVE: The objective of the study was to evaluate an investigational testosterone transdermal patch (TTP) designed to deliver the normal ovarian production rate of testosterone. DESIGN: This was an open-label study (2-month baseline period followed by 2-month treatment period). PATIENTS: Nine women with sPOF and a history of regular bleeding patterns on standard estrogen/progestogen cyclic treatment participated in the study. One subject with abnormal baseline levels was excluded. INTERVENTION: Four consecutive 28-d cycles of transdermal estradiol (E2; 0.1 mg/d) and sequential oral medroxyprogesterone acetate (MPA; 10 mg/d for the last 12 d of each cycle). During cycles 3 and 4, an investigational TTP (nominal delivery 150 microg/d) was applied twice weekly to the abdomen. MAIN OUTCOME MEASURES: Steady-state pharmacokinetic profiles of free and total testosterone and scheduled vaginal bleeding patterns were studied. RESULTS: The mean (95% confidence interval) of the time-average free testosterone levels during TTP treatment was 7.5 (4.9-9.9) pg/ml; 26.0 (17.2-34.6) pmol/liter (with E2), and 6.9 (4.9-8.8) pg/ml; 23.9 (17.2-30.5) pmol/liter (with E2 and MPA). The confidence intervals of the means include the upper limit of normal for premenopausal women, i.e. 6.8 pg/ml (23.5 pmol/liter), although the mean values are slightly above this. CONCLUSIONS: The addition of TTP to cyclic E2/MPA therapy in women with sPOF produced mean free testosterone levels that approximate the upper limit of normal. A 3-yr study to assess safety and effectiveness in this population is in progress.


Assuntos
Androgênios/administração & dosagem , Insuficiência Ovariana Primária/tratamento farmacológico , Testosterona/administração & dosagem , Administração Cutânea , Adulto , Androgênios/efeitos adversos , Androgênios/uso terapêutico , Feminino , Hormônios/sangue , Humanos , Ciclo Menstrual/efeitos dos fármacos , Projetos Piloto , Insuficiência Ovariana Primária/sangue , Insuficiência Ovariana Primária/fisiopatologia , Testosterona/efeitos adversos , Testosterona/uso terapêutico
19.
J Clin Endocrinol Metab ; 87(7): 3197-200, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12107224

RESUMO

Classic congenital adrenal hyperplasia due to 21-hydroxylase deficiency is characterized by a defect in cortisol and aldosterone secretion and adrenal hyperandrogenism. Current treatment is to provide adequate glucocorticoid and mineralocorticoid substitution to prevent adrenal crises and to suppress excess adrenal androgen secretion. Satisfactory adrenocortical suppression often requires supraphysiological doses of hydrocortisone, which may produce an unacceptable degree of hypercortisolism. A new four-drug treatment regimen of flutamide, testolactone, reduced hydrocortisone dose, and 9alpha-fludrocortisone has been shown to achieve normal growth and development after 2 yr of therapy and may, therefore, represent a potential alternative approach to the treatment of children with classic congenital adrenal hyperplasia. We investigated the effect of flutamide and testolactone, and flutamide alone, on cortisol clearance by performing clearance studies twice in 13 children (6 males and 7 females; age range, 7.0-14.5 yr) with classic 21-hydroxylase deficiency. All studies were conducted at least 3 months after institution of the four-drug treatment regimen. In eight patients (group 1), the first cortisol clearance study was performed on the four-drug regimen, and the second study was performed after a 48-h washout period off flutamide and testolactone. In five patients (group 2), the first study was conducted 1 wk after discontinuation of testolactone and while patients were receiving flutamide, hydrocortisone and 9alpha-fludrocortisone, and the second study was performed after a 48-h washout period off flutamide. Oral hydrocortisone was held on the day of the clearance studies, and all patients received a continuous infusion of hydrocortisone (0.6 mg/m(2).h) from 1800 h to 0200 h, with cortisol concentrations measured once hourly. In addition, an in vitro study was conducted to exclude the possibility of an analytical interference of flutamide, 2-hydroxyflutamide, and testolactone with the serum cortisol immunoassay. Total body cortisol clearance was significantly lower during treatment with the four-drug regimen than during treatment with hydrocortisone and 9alpha-fludrocortisone (153.5 +/- 26.8 vs.355.4 +/- 65.8 ml/min; P = 0.001). Similar results were obtained comparing flutamide, hydrocortisone, and 9alpha-fludrocortisone therapy to hydrocortisone and 9alpha-fludrocortisone therapy (155.8 +/- 26.5 vs. 281.8 +/- 96.2 ml/min; P = 0.037). The in vitro study indicated that an interference with the serum cortisol immunoassay was unlikely. These findings indicate that the addition of flutamide and testolactone to the treatment regimen of hydrocortisone and 9alpha-fludrocortisone decreases cortisol clearance in patients with classic 21-hydroxylase deficiency, and this effect seems to be due to flutamide. Glucocorticoid replacement doses should be reduced when flutamide is added to the treatment regimen of patients receiving hydrocortisone.


Assuntos
Hiperplasia Suprarrenal Congênita/tratamento farmacológico , Hiperplasia Suprarrenal Congênita/metabolismo , Antagonistas de Androgênios/uso terapêutico , Cortisona/análogos & derivados , Flutamida/uso terapêutico , Hidrocortisona/metabolismo , Hiperplasia Suprarrenal Congênita/etiologia , Criança , Cortisona/administração & dosagem , Cortisona/uso terapêutico , Relação Dose-Resposta a Droga , Quimioterapia Combinada , Feminino , Humanos , Hidrocortisona/administração & dosagem , Hidrocortisona/uso terapêutico , Masculino , Erros Inatos do Metabolismo/complicações , Testolactona/uso terapêutico
20.
J Clin Endocrinol Metab ; 89(9): 4258-63, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15356018

RESUMO

To examine leptin's role in human appetite regulation, we studied recombinant methionyl human leptin's effects on satiation and satiety in a model of leptin insufficiency, lipodystrophy. Eight females with hypoleptinemia and lipodystrophy were given sc injections of A-100 (maximal dose, 200% of that predicted to normalize serum leptin) for 4 months. Satiation and satiety were determined before and again during leptin treatment. Satiation was measured as the time to voluntary cessation of eating from a standardized food array after a 12-h fast. Satiety was determined as the time to hunger sufficient to consume a full meal after consumption of a standardized preload. During leptin treatment, satiation time decreased (41.2 +/- 18.2 to 19.5 +/- 10.6 min; P = 0.01), satiety time increased (62.9 +/- 64.8 to 137.8 +/- 91.6 min; P = 0.04), energy consumed to produce satiation decreased (2034 +/- 405 to 1135 +/- 432 kcal or 8.5 +/- 1.7 to 4.7 +/- 1.8 MJ; P < 0.01), and the amount of food desired in the postabsorptive state decreased (P < 0.02). Ghrelin concentrations also decreased during leptin administration (284.3 +/- 127.9 to 140.6 +/- 104.5 pmol/liter; P < 0.002). We conclude that increased leptin in patients with lipodystrophy results in less caloric, shorter, more satiating meals and longer-lived satiety. These data support the hypothesis that leptin plays an important, permissive role in human appetite regulation.


Assuntos
Leptina/deficiência , Leptina/uso terapêutico , Lipodistrofia/tratamento farmacológico , Saciação/efeitos dos fármacos , Adolescente , Adulto , Metabolismo Energético , Feminino , Humanos , Lipodistrofia/metabolismo , Lipodistrofia/psicologia
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