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1.
Gynecol Oncol ; 143(2): 398-405, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27538367

RESUMO

BACKGROUND: Forkhead box protein A2 (FOXA2) plays an important in development, cellular metabolism and tumorigenesis. The Cancer Genome Atlas (TCGA) identified a modest frequency of FOXA2 mutations in endometrioid endometrial cancers (EEC). The current study sought to determine the relationship between FOXA2 mutation and clinicopathologic features in EEC and FOXA2 expression. METHODS: Polymerase chain reaction (PCR) amplification and sequencing were used to identify mutations in 542 EEC. Western blot, quantitative reverse transcriptase PCR (qRT-PCR) and immunohistochemistry (IHC) were used to assess expression. Methylation analysis was performed using combined bisulfite restriction analysis (COBRA) and sequencing. Chi-squared, Fisher's exact, Student's t- and log-rank tests were performed. RESULTS: Fifty-one mutations were identified in 49 tumors (9.4% mutation rate). The majority of mutations were novel, loss of function (LOF) (78.4%) mutations, and most disrupted the DNA-binding domain (58.8%). Six recurrent mutations were identified. Only two tumors had two mutations and there was no evidence for FOXA2 allelic loss. Mutation status was associated with tumor grade and not associated with survival outcomes. Methylation of the FOXA2 promoter region was highly variable. Most tumors expressed FOXA2 at both the mRNA and protein level. In those tumors with mutations, the majority of cases expressed both alleles. CONCLUSION: FOXA2 is frequently mutated in EEC. The pattern of FOXA2 mutations and expression in tumors suggests complex regulation and a haploinsufficient or dominant-negative tumor suppressor function. In vitro studies may shed light on how mutations in FOXA2 affect FOXA2 pioneer and/or transcription factor functions in EEC.


Assuntos
Carcinoma Endometrioide/patologia , Neoplasias do Endométrio/genética , Genes Supressores de Tumor , Fator 3-beta Nuclear de Hepatócito/genética , Mutação , Idoso , Endométrio/metabolismo , Feminino , Humanos , Pessoa de Meia-Idade
2.
Cancer Epidemiol ; 88: 102499, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38056245

RESUMO

INTRODUCTION: Pediatric and young adult brain tumors (PYBT) account for a large share of cancer-related morbidity and mortality among children in the United States, but their etiology is not well understood. Previous research suggests the Appalachian region of Kentucky has high rates of PYBT. This study explored PYBT incidence over 25 years in Kentucky to identify geographic and temporal trends and generate hypotheses for future research. METHODS: The Kentucky Cancer Registry contributed data on all PYBT diagnosed among those aged 0-29 during years 1995-2019. Age- and sex-adjusted spatio-temporal scan statistics-one for each type of PYBT, and one for all types-comprised the primary analysis. These results were mapped along with environmental and occupational data. RESULTS: Findings indicated that north-central Kentucky and the Appalachian region experienced higher rates of some PYBT. High rates of astrocytomas were clustered in a north-south strip of central Kentucky toward the end of the study period, while high rates of other specified types of intracranial and intraspinal neoplasms were significantly clustered in eastern Kentucky. The area where these clusters overlapped, in north-central Kentucky, had significantly higher rates of PYBT generally. DISCUSSION: This study demonstrates north-central Kentucky and the Appalachian region experienced higher PYBT risk than the rest of the state. These regions are home to some of Kentucky's signature industries, which should be examined in further research. Future population-based and individual-level studies of genetic factors are needed to explore how the occupations of parents, as well as prenatal and childhood exposures to pesticides and air pollutants, impact PYBT incidence.


Assuntos
Neoplasias Encefálicas , Humanos , Criança , Adulto Jovem , Kentucky/epidemiologia , Região dos Apalaches/epidemiologia , Neoplasias Encefálicas/epidemiologia , Incidência , Coleta de Dados
3.
Int J STD AIDS ; 21(5): 342-5, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20498104

RESUMO

We conducted a cross-sectional study with 208 HIV-uninfected and 188 HIV-infected women in Uganda and Zimbabwe to investigate differences in median CD4 counts. Absolute CD4 counts were determined by flow cytometry. Multivariate analyses were used to examine the association of country and HIV-infection status on CD4 counts. Median CD4 counts were significantly lower in Zimbabwe than in Uganda overall (649 and 783 cells/mm(3), P = 0.009) and among HIV-infected women (470 and 614 cells/mm(3), P = 0.003). In separate multivariable models, CD4 counts were significantly lower in Zimbabwe in HIV-uninfected (P = 0.014) and infected (P < 0.001) women, controlling for age, contraceptive method, education and living with partner status. In a model combining HIV-uninfected and infected women, there was no significant interaction between country and HIV infection status (P = 0.344), suggesting that the relationship between country and CD4 count was not significantly modified by HIV infection status. This study reinforces the importance of establishing country-specific reference CD4 levels as CD4 count continues to be used as a key biomarker in clinical decision-making for HIV-infected individuals in sub-Saharan Africa.


Assuntos
Contagem de Linfócito CD4 , Infecções por HIV/imunologia , Adolescente , Adulto , Anticoncepcionais Orais , Estudos Transversais , Feminino , Infecções por HIV/epidemiologia , Humanos , Gravidez , Estudos de Amostragem , Uganda/epidemiologia , Adulto Jovem , Zimbábue/epidemiologia
4.
Spat Spatiotemporal Epidemiol ; 35: 100364, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33138948

RESUMO

Population-based ecological and cross-sectional studies have observed high risk for several cancers in areas of Central Appalachia where mountaintop removal coal mines operate. Case-control studies could provide stronger evidence of such relationships, but misclassification of exposure is likely when based on current residence, since individuals could have inhabited several residences with varying environmental exposures over many years. To address this, we used residential histories for individuals enrolled in a previous case-control study of lung cancer to assess residential proximity to mountaintop removal coal mining over a 30-year period, using both survey data and proprietary data from LexisNexis, Inc. Supplementing the survey data with LexisNexis data improved precision and completeness of geographic coordinates. Final logistic regression models revealed higher odds of high exposure among cases. These findings suggest that living in close proximity to mountaintop removal coal mining sites could increase risk for lung cancer, after adjusting for other relevant factors.


Assuntos
Minas de Carvão , Exposição Ambiental/efeitos adversos , Neoplasias Pulmonares/epidemiologia , Adulto , Fatores Etários , Idoso , Região dos Apalaches/epidemiologia , Estudos de Casos e Controles , Fatores de Confusão Epidemiológicos , Feminino , Humanos , Neoplasias Pulmonares/etiologia , Masculino , Pessoa de Meia-Idade , Características de Residência , Fatores Sexuais , Análise Espaço-Temporal , Inquéritos e Questionários
5.
Leukemia ; 31(6): 1278-1285, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-27843138

RESUMO

Core-binding factor acute myeloid leukemia (CBF-AML) is defined by the presence of either t(8;21)(q22;q22)/RUNX1-RUNX1T1 or inv(16)(p13.1q22)/t(16;16)(p13.1;q22)/CBFB-MYH11. The resulting fusion genes require a 'second hit' to initiate leukemogenesis. Mutation assessment of 177 adults with CBF-AML, including 68 with t(8;21) and 109 with inv(16)/t(16;16), identified not only mutations well known in CBF-AML but also mutations in the CCND1 and CCND2 genes, which represent novel frequent molecular alterations in AML with t(8;21). Altogether, CCND1 (n=2) and CCND2 (n=8) mutations were detected in 10 (15%) patients with t(8;21) in our cohort. A single CCND2 mutation was also found in 1 (0.9%) patient with inv(16). In contrast, CCND1 and CCND2 mutations were detected in only 11 (0.77%) of 1426 non-CBF-AML patients. All CCND2 mutations cluster around the highly conserved amino-acid residue threonine 280 (Thr280). We show that Thr280Ala-mutated CCND2 leads to increased phosphorylation of the retinoblastoma protein, thereby causing significant cell cycle changes and increased proliferation of AML cell lines. The identification of CCND1 and CCND2 mutations as frequent mutational events in t(8;21) AML may provide further justification for cell cycle-directed therapy in this disease.


Assuntos
Cromossomos Humanos Par 21 , Cromossomos Humanos Par 8 , Ciclina D1/genética , Ciclina D2/genética , Leucemia Mieloide Aguda/genética , Mutação , Translocação Genética , Adolescente , Adulto , Idoso , Biomarcadores Tumorais/genética , Feminino , Seguimentos , Humanos , Leucemia Mieloide Aguda/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Taxa de Sobrevida , Adulto Jovem
6.
Leukemia ; 31(10): 2211-2218, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28321123

RESUMO

Recurrent chromosomal abnormalities and gene mutations detected at the time of diagnosis of acute myeloid leukemia (AML) are associated with particular disease features, treatment response and survival of AML patients, and are used to denote specific disease entities in the World Health Organization classification of myeloid neoplasms and acute leukemia. However, large studies that integrate cytogenetic and comprehensive mutational information are scarce. We created a comprehensive oncoprint of mutations associated with recurrent cytogenetic findings by combining the information on mutational patterns of 80 cancer- and leukemia-associated genes with cytogenetic findings in 1603 adult patients with de novo AML. We show unique differences in the mutational profiles among major cytogenetic subsets, identify novel associations between recurrent cytogenetic abnormalities and both specific gene mutations and gene functional groups, and reveal differences in cytogenetic and mutational features between patients younger than 60 years and those aged 60 years or older. The identified associations between cytogenetic and molecular genetic data may help guide mutation testing in AML, and result in more focused application of targeted therapy in patients with de novo AML.


Assuntos
Aberrações Cromossômicas , Ontologia Genética , Genes Neoplásicos , Leucemia Mieloide Aguda/genética , Mutação , Adulto , Fatores Etários , Idoso , Análise Mutacional de DNA , DNA de Neoplasias/genética , Feminino , Humanos , Cariotipagem , Masculino , Pessoa de Meia-Idade
7.
Cochrane Database Syst Rev ; (1): CD004717, 2005 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-15674963

RESUMO

BACKGROUND: Distraction techniques are a form of coping strategies used in cognitive behavioural techniques. They may be of value as an adjunctive treatment for people with schizophrenia or schizophrenia-like illnesses. OBJECTIVES: To review the effects of distraction techniques for people with schizophrenia. SEARCH STRATEGY: We searched the Cochrane Schizophrenia Group's Register (October 2003), manually searched reference lists and contacted relevant authors. SELECTION CRITERIA: We included all randomised controlled trials comparing distraction techniques with other treatments for schizophrenia. DATA COLLECTION AND ANALYSIS: We reliably selected, quality assessed and data extracted studies. We excluded data where more than 50% of participants in any group were lost to follow up. For binary outcomes, we calculated a fixed effects risk ratio (RR) and its 95% confidence interval (CI), along with the number needed to treat/harm (NNT/H). For continuous data we calculated the weighted mean difference (WMD). MAIN RESULTS: In terms of mental state, distraction techniques did not have a clear effect (n=60, 1 RCT, MD endpoint BPRS 1.60 CI -0.49 to 3.69). Distraction does not obviously engage people in the studies (n=159, 5 RCTs, RR leaving the study before completion 1.08 CI 0.72 to 1.63). AUTHORS' CONCLUSIONS: Clinicians, researchers, policy makers and recipients of care cannot be confident of the effects of distraction techniques from the findings of this review. The few pioneering studies are small, short and poorly reported. Further data from already completed trials might help inform practice, but more trials do seem to be justified as some of these potentially simple techniques, even if their effect is negligible, could be widely implemented and prove more acceptable than other more intrusive treatments.


Assuntos
Adaptação Psicológica , Terapia Cognitivo-Comportamental/métodos , Esquizofrenia/terapia , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto
8.
Arch Intern Med ; 147(7): 1297-301, 1987 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-3606287

RESUMO

Computerized information systems hold the promise of overcoming problems in the management of clinical information Many of the claims of the creators and promoters of these systems, however, are not based on sound clinical studies. To determine the ability of computer information systems to improve the quality of medical care, we applied methodologic criteria to published articles in the field. Only 30 (22%) of 135 articles reported preplanned investigations, and only half of these met minimal criteria for scientific investigations. Fourteen studies were well designed and executed. All studies reported improvements in the process of care. However, patient outcomes were not measured, not affected, or only minimally influenced. While computer information systems show increasing potential, more work is required to enhance their effect on the quality of care and thus on patient outcomes.


Assuntos
Computação em Informática Médica , Garantia da Qualidade dos Cuidados de Saúde , Estudos de Avaliação como Assunto
9.
Arch Intern Med ; 159(15): 1771-6, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10448781

RESUMO

OBJECTIVES: To ascertain whether prolonged suppression of viral replication can be achieved in clinical practice and to identify factors associated with virological outcome. DESIGN: Retrospective observational study. SETTING: University-affiliated human immunodeficiency virus (HIV) clinic in Cleveland, Ohio. PARTICIPANTS: Patients treated with regimens that included protease inhibitors between June 1995 and December 1997. We identified 366 patients; 310 had sufficient virological follow-up data to be included. MAIN OUTCOME MEASURE: Virological success was defined as plasma HIV-RNA levels lower than 400 copies/mL at the last clinic visit. Virological failure was subdivided according to the maximum degree of suppression of viral replication achieved. Multivariate analysis was performed to identify baseline factors associated with virological outcome. RESULTS: Virological success was achieved by 47% of patients at a median follow-up of 335 days. The median CD4+ cell count increase and HIV-RNA level decrease were 0.10x10(9)/L (100 cells/microL) and greater than 1.3 log10 in patients who achieved virological success, and 0.010x10(9)/L and 0.32 log10 for those who did not. In multivariate analysis the likelihood of virological success was diminished in women (P<.02) and in patients who missed 2 or more clinic visits in the prior year (P<.001), and decreased when the regimen was started earlier (P<.04). Patients with a lower nadir CD4+ cell count (P<.04) and higher peak plasma HIV-RNA levels (P<.001) also had a decreased likelihood of virological success. CONCLUSIONS: More than half the patients who started a regimen that included protease inhibitors in an academic clinical practice failed to achieve durable suppression of viral replication and also experienced a poorer immunologic outcome as determined by CD4+ cell count increase. Missed clinic visits, more advanced disease, and higher plasma HIV-RNA levels may predict failure.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Infecções por HIV/tratamento farmacológico , Inibidores da Protease de HIV/uso terapêutico , Adolescente , Adulto , Idoso , Contagem de Linfócito CD4 , Feminino , HIV/enzimologia , HIV/genética , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , RNA Viral/sangue , Estudos Retrospectivos , Resultado do Tratamento , Carga Viral/métodos
10.
Drug Test Anal ; 7(7): 609-18, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25284752

RESUMO

Twenty-four products suspected of containing anabolic steroids and sold in fitness equipment shops in the United Kingdom (UK) were analyzed for their qualitative and semi-quantitative content using full scan gas chromatography-mass spectrometry (GC-MS), accurate mass liquid chromatography-mass spectrometry (LC-MS), high pressure liquid chromatography with diode array detection (HPLC-DAD), UV-Vis, and nuclear magnetic resonance (NMR) spectroscopy. In addition, X-ray crystallography enabled the identification of one of the compounds, where reference standard was not available. Of the 24 products tested, 23 contained steroids including known anabolic agents; 16 of these contained steroids that were different to those indicated on the packaging and one product contained no steroid at all. Overall, 13 different steroids were identified; 12 of these are controlled in the UK under the Misuse of Drugs Act 1971. Several of the products contained steroids that may be considered to have considerable pharmacological activity, based on their chemical structures and the amounts present. This could unwittingly expose users to a significant risk to their health, which is of particular concern for naïve users.


Assuntos
Anabolizantes/análise , Suplementos Nutricionais/análise , Dopagem Esportivo , Saúde Pública/tendências , Esteroides/análise , Levantamento de Peso , Cromatografia Líquida/métodos , Cristalografia por Raios X , Suplementos Nutricionais/efeitos adversos , Fatores de Risco , Esteroides/efeitos adversos , Espectrometria de Massas em Tandem/métodos
11.
J Invest Dermatol ; 96(1): 65-70, 1991 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-1987298

RESUMO

The precise biochemical mechanism and site(s) of action by which minoxidil stimulates hair growth are not yet clear. Minoxidil sulfate is the active metabolite of minoxidil, with regard to smooth muscle vasodilation and hair growth. Formation of minoxidil sulfate is catalyzed by specific PAPS-dependent sulfotransferase(s) and minoxidil-sulfating activities have been previously reported to be present in liver and hair follicles. One of these minoxidil-sulfating enzymes has been purified from rat liver (rat minoxidil sulfotransferase, MST) and a rabbit anti-MST antibody has been prepared. Using this anti-MST antibody, we have immunohistochemically localized minoxidil sulfotransferase in the liver and anagen hair follicles from rat. In rat pelage and vibrissa follicles, this enzyme is localized within the cytoplasm of epithelial cells in the lower outer root sheath. Although the immunolocalization of MST might not necessarily correlate with the MST activity known to be present in anagen follicles, the results of this study strongly suggest that the lower outer root sheath of the hair follicle may serve as a site for the sulfation of topically applied minoxidil.


Assuntos
Cabelo/enzimologia , Sulfotransferases/metabolismo , Vibrissas/enzimologia , Animais , Feminino , Técnicas Imunoenzimáticas , Fígado/enzimologia , Ratos , Ratos Endogâmicos F344
12.
Bone ; 10(1): 3-6, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2736154

RESUMO

We have previously reported an increase in forearm bone mineral content (BMC) during therapy for osteoporosis with the anabolic steroid, nandrolone decanoate. However, it has recently been claimed that part of this increase is spurious, due to a decrease in forearm fat during the treatment. We have therefore analyzed the data from a cross-over study of the effects of this agent on 70 osteoporotic women, using the fat correction procedure supplied by the manufacturer of the forearm densitometer. There was a significant rise (p less than 0.001) in the mean fat-corrected BMC (BMC[fc]) on nandrolone decanoate (50 mg intramuscularly every 2 or 3 weeks) and a non-significant fall in mean BMC[fc] off the drug. The mean time-weighted rate of change in the fat-corrected value was +29 +/- 5 mg/cm/year on nandrolone decanoate and -5 +/- 5 mg/cm/year off nandrolone decanoate (p less than 0.001). Nandrolone decanoate produces a significant gain in forearm mineral content even after allowing for changes in forearm fat content during therapy.


Assuntos
Anabolizantes/uso terapêutico , Osso e Ossos/análise , Minerais/análise , Nandrolona/análogos & derivados , Osteoporose/tratamento farmacológico , Idoso , Feminino , Antebraço , Humanos , Lipídeos/análise , Pessoa de Meia-Idade , Nandrolona/uso terapêutico , Decanoato de Nandrolona , Cintilografia
13.
Am J Cardiol ; 60(7): 572-5, 1987 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-3630939

RESUMO

Previous reports suggest that the finding of left atrial (LA) dilatation (greater than 45 mm) by echocardiography identifies patients not likely to maintain sinus rhythm after conversion of atrial fibrillation (AF). However, these studies antedate the availability of amiodarone, an antiarrhythmic agent that reportedly is effective in patients with AF in whom other drug therapy has failed. To analyze the relation between LA size and the ability to maintain sinus rhythm with amiodarone therapy, 28 patients, aged 32 to 87 years (mean 61), with an LA dimension greater than 45 mm (range 46 to 78, mean 57) were studied. Thirteen patients (46%) had valvular heart disease, 10 (36%) dilated cardiomyopathy and 5 (18%) miscellaneous disorders. In 25 patients (89%) quinidine therapy had failed. After therapy with amiodarone, sinus rhythm returned in all patients and was maintained. Therapy was judged completely successful in 10 patients (alive and still in sinus rhythm with at least 1 year of follow-up), partially successful in 11 (maintaining sinus rhythm for at least 6 months before a change in status) and failed in 7. Completely successful therapy was accomplished in 9 of 18 patients with an LA dimension between 46 and 60 mm, but in only 1 of 10 patients with an LA dimension greater than 60 mm (p less than 0.05). Thus, patients with LA dimensions between 46 and 60 mm who are significantly compromised by AF can often be maintained in sinus rhythm with amiodarone therapy. However, in patients with larger LA dimensions. AF is likely to return despite aggressive antiarrhythmic therapy with amiodarone, a drug with potentially serious side effects.


Assuntos
Amiodarona/uso terapêutico , Fibrilação Atrial/tratamento farmacológico , Átrios do Coração/patologia , Adulto , Idoso , Fibrilação Atrial/patologia , Cardiomiopatia Dilatada/patologia , Feminino , Doenças das Valvas Cardíacas/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Fatores de Tempo
14.
J Endocrinol ; 131(1): 147-54, 1991 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1744555

RESUMO

Abnormal ratios of testosterone to epitestosterone (T/E) and testosterone to LH (T/LH) in the urine of male athletes are indicative of testosterone administration. The T/E ratio has been adopted by the International Olympic Committee as the sole criterion used in the detection of testosterone administration. An athlete is usually considered to have failed a drug test if the urinary T/E ratio is greater than 6. Human chorionic gonadotrophin (hCG) has been used by some male athletes to stimulate testicular secretion of testosterone. The purpose of this investigation was to examine whether the urinary T/E ratio can remain unaffected by administration of hCG to normal adult males. Administration of hCG resulted in large increases in serum testosterone concentrations and urinary T/LH ratios but small changes in urinary T/E ratios of two subjects (maximum T/E values observed were 0.8 and 1.2 respectively). These observations suggest that the urinary T/LH ratio is a valuable indicator of hCG as well as of testosterone administration. This study is the first to measure urinary T/LH ratios using the technique of gas chromatography-mass spectrometry for quantification of testosterone, and highly specific monoclonal antibodies for the measurement of LH. An ultrafiltration method is proposed as part of a confirmatory procedure to be adopted in the measurement of urinary gonadotrophins for drug control in sport.


Assuntos
Gonadotropina Coriônica/farmacologia , Dopagem Esportivo , Detecção do Abuso de Substâncias/métodos , Testosterona/farmacologia , Epitestosterona/urina , Cromatografia Gasosa-Espectrometria de Massas/métodos , Humanos , Imunoensaio/métodos , Hormônio Luteinizante/urina , Masculino , Testosterona/sangue , Testosterona/urina , Ultrafiltração/métodos
15.
J Steroid Biochem Mol Biol ; 42(1): 87-94, 1992 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-1558821

RESUMO

Dihydrotestosterone (DHT) can be used by an athlete as an anabolic steroid to evade the current International Olympic Committee approved drug tests. To investigate the possibility of a method for its detection, the heptanoate ester of DHT was administered to two male subjects (150 mg i.m.). Urine samples, collected before and after the injection, were subjected to enzymatic hydrolysis and the excretion rates of DHT, 5 alpha-androstane-3 alpha,17 beta-diol (3 alpha-diol) and testosterone (T) were determined by radioimmunoassay. Relative changes in the excretion of DHT, 3 alpha-diol, 5 alpha-androstane-3 beta,17 beta-diol (3 beta-diol), 5 beta-androstane-3 alpha, 17 beta-diol (5 beta-diol), T and epitestosterone (17 alpha hydroxyandrost-4-en-3-one; Epi-T) were determined by gas chromatography-mass spectrometry (GC-MS). Following administration of DHT, the urinary excretion rates of DHT, 3 alpha-diol and 3 beta-diol increased when compared to those of T, Epi-T, 5 beta-diol and luteinizing hormone (LH). Concentrations of DHT in the plasma increased whereas those of T, LH and follicle stimulating hormone decreased. The changes following such modest doses of DHT suggest that these ratios of urinary hormones may be used for the detection of doping with DHT.


Assuntos
Di-Hidrotestosterona/urina , Esportes , Adulto , Idoso , Androstano-3,17-diol/urina , Cromatografia Líquida de Alta Pressão , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Hormônio Luteinizante/urina , Masculino , Radioimunoensaio , Testosterona/urina
16.
J Am Med Inform Assoc ; 1(6): 447-58, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-7850570

RESUMO

OBJECTIVE: To develop optimal MEDLINE search strategies for retrieving sound clinical studies of the etiology, prognosis, diagnosis, prevention, or treatment of disorders in adult general medicine. DESIGN: Analytic survey of operating characteristics of search strategies developed by computerized combinations of terms selected to detect studies meeting basic methodologic criteria for direct clinical use in adult general medicine. MEASURES: The sensitivities, specificities, precision, and accuracy of 134,264 unique combinations of search terms were determined by comparison with a manual review of all articles (the "gold standard") in ten internal medicine and general medicine journals for 1986 and 1991. RESULTS: Less than half of the studies of the topics of interest met basic criteria for scientific merit for testing clinical applications. Combinations of search terms reached peak sensitivities of 82% for sound studies of etiology, 92% for prognosis, 92% for diagnosis, and 99% for therapy in 1991. Compared with the best single terms, multiple terms increased sensitivity for sound studies by over 30% (absolute increase), but with some loss of specificity when sensitivity was maximized. For 1986, combinations reached peak sensitivities of 72% for etiology, 95% for prognosis, 86% for diagnosis, and 98% for therapy. When search terms were combined to maximize specificity, over 93% specificity was achieved for all purpose categories in both years. Compared with individual terms, combined terms achieved near-perfect specificity that was maintained with modest increases in sensitivity in all purpose categories except therapy. Increases in accuracy were achieved by combining terms for all purpose categories, with peak accuracies reaching over 90% for therapy in 1986 and 1991. CONCLUSIONS: The retrieval of studies of important clinical topics cited in MEDLINE can be substantially enhanced by selected combinations of indexing terms and textwords.


Assuntos
MEDLINE , Terminologia como Assunto , Diagnóstico , Métodos Epidemiológicos , Prognóstico , Projetos de Pesquisa , Terapêutica
17.
J Am Med Inform Assoc ; 1(3): 285-95, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-7719810

RESUMO

OBJECTIVE: To compare the performances of online and compact-disc (CD-ROM) versions of the National Library of Medicine's (NLM) MEDLINE database. DESIGN: Analytic survey. INTERVENTION: Clinical questions were drawn from 18 searches originally conducted spontaneously by clinicians from wards and clinics who had used Grateful Med Version 4.0. Clinicians' search strategies were translated to meet the specific requirements of 13 online and 14 CD-ROM MEDLINE systems. A senior librarian and vendors' representatives constructed independent searches from the clinicians' questions. The librarian and clinician searches were run through each system, in command mode for the librarian and menu mode for clinicians, when available. Vendor searches were run through the vendors' own systems only. MAIN MEASUREMENTS: Numbers of relevant and irrelevant citations retrieved, cost (for online systems only), and time. RESULTS: Systems varied substantially for all searches, and for librarian and clinician searches separately, with respect to the numbers of relevant and irrelevant citations retrieved (p < 0.001 for both) and the cost per relevant citation (p = 0.012), but not with respect to the time per search. Based on combined rankings for the highest number of relevant and the lowest number of irrelevant citations retrieved, the SilverPlatter CD-ROM MEDLINE clinical journal subset performed best for librarian searches, while the PaperChase online system worked best for clinician searches. For cost per relevant citation retrieved, Dialog's Knowledge Index performed best for both librarian and clinician searches. CONCLUSIONS: There were substantial differences in the performances of competing MEDLINE systems, and performance was affected by search strategy, which was conceived by a librarian or by clinicians.


Assuntos
CD-ROM , MEDLINE , Indexação e Redação de Resumos , CD-ROM/economia , CD-ROM/estatística & dados numéricos , Custos e Análise de Custo , Estudos de Avaliação como Assunto , Grateful Med , Bibliotecários , MEDLINE/economia , MEDLINE/estatística & dados numéricos , Médicos , Descritores
18.
J Mass Spectrom ; 31(4): 397-402, 1996 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8799284

RESUMO

Six laboratories in six countries collaborated to investigate the analytical method for estimating the testosterone to epitestosterone ratio (T/E) in urine by gas chromatography/mass spectrometry in the context of detecting the application of T as a doping agent in sport. The protocol specified many but not all details of reagents and instrument conditions. The design included the distribution and analysis of four urines with different T/E values, three replicates per value, and one standard. The ranges of mean T/E values for the four urines estimated by peak area (PA) were 0.32-0.42, 0.72-0.94, 0.91-1.14 and 3.19-5.48. The analyses of variance for these data and for the peak height (PH) data were significant for the laboratory factor (p < 0.0001). In addition there was a significant interaction between the urine factor and the laboratory factor which indicates the complexity of the analysis. T/E calculated using PA was not significantly different from that using PH. For within-laboratory precision all values for PH and PA were < 8.3%, and for between-laboratory precision all values were < 11.7% except for one (20.1%). The data represent a baseline for future experiments designed to elucidate the sources of within-and between-laboratory variance, and to harmonize estimates of T/E.


Assuntos
Epitestosterona/urina , Testosterona/urina , Análise de Variância , Dopagem Esportivo , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Indicadores e Reagentes , Laboratórios , Padrões de Referência , Reprodutibilidade dos Testes
19.
Acad Med ; 64(4): 207-12, 1989 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2647092

RESUMO

Physicians have considerable difficulty collecting and interpreting information from patients, dealing with the uncertainties associated with diagnosing and treating their patients, communicating precisely with one another, keeping up to date, and applying recommended procedures when indicated. Some of the advances in information technology may help physicians to manage information more effectively through more accessible, validated clinical indexes, data bases of diagnostic test characteristics, computerized audits of clinical activities with feedback, expert systems, on-line access to the medical literature, and other tools of medical informatics. Medical educators can catalyze this process by facilitating the introduction of information technology into academic clinical settings so that students can learn its use first-hand and by promoting the evolution of this and other aspects of medical informatics, a new discipline dedicated to the solution of information problems in health care. The potential roles for computer-aided instruction and centralized computer laboratories in medical schools are much less clear.


Assuntos
Educação Médica , Informática Médica , Canadá , Comunicação , Diagnóstico por Computador , Educação Médica Continuada , Humanos , Sistemas de Informação , Relações Interprofissionais , Estados Unidos
20.
Anal Bioanal Chem ; 355(7-8): 801-2, 1996 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15045268

RESUMO

Direct slurry analysis by FI ICP-AES has been tested on seven iron-containing and five zinc-containing minerals. Results indicate that the method can be applied for traces and majors in a range of different materials.

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