RESUMO
OBJECTIVE: To evaluate racial and ethnic disparities in utilization of total knee arthroplasty (TKA) in relation to demographic, health, and socioeconomic status variables. DESIGN: Prospective study of 102,767 Women's Health Initiative postmenopausal women initially aged 50-79, examining utilization rates of primary TKA between non-Hispanic Black/African American, non-Hispanic White, and Hispanic/Latina women (hereafter referred to as Black, White, and Hispanic). A total of 8,942 Black, 3,405 Hispanic, and 90,420 White women with linked Medicare claims data were followed until time of TKA, death, or transition from fee-for-service coverage. Absolute disparities were determined using utilization rates by racial/ethnic group and relative disparities quantified using multivariable hazards models in adjusting for age, arthritis, joint pain, mobility disability, body mass index, number of comorbidities, income, education, neighborhood socioeconomic status (SES), and geographic region. RESULTS: TKA utilization was higher among White women (10.7/1,000 person-years) compared to Black (8.5/1,000 person-years) and Hispanic women (7.6/1,000 person-years). Among women with health indicators for TKA including diagnosis of arthritis, moderate to severe joint pain, and mobility disability, Black and Hispanic women were significantly less likely to undergo TKA after adjusting for age [Black: HR (95% confidence interval) = 0.70 (0.63-0.79); Hispanic: HR = 0.58 (0.44-0.77)]. Adjustment for SES modestly attenuated the measured disparity, but significant differences remained [Black: HR = 0.75 (0.67-0.89); Hispanic: HR = 0.65 (0.47-0.89)]. CONCLUSIONS: Compared to White women, Black and Hispanic women were significantly less likely to undergo TKA after considering need and appropriateness for TKA and SES. Further investigation into personal-level and provider-level factors that may explain these disparities is warranted.
Assuntos
Artralgia/cirurgia , Artrite Reumatoide/cirurgia , Artroplastia do Joelho/estatística & dados numéricos , Etnicidade/estatística & dados numéricos , Disparidades em Assistência à Saúde/etnologia , Limitação da Mobilidade , Osteoartrite do Joelho/cirurgia , Negro ou Afro-Americano/estatística & dados numéricos , Idoso , Artralgia/epidemiologia , Artrite Reumatoide/epidemiologia , Feminino , Hispânico ou Latino/estatística & dados numéricos , Humanos , Medicare , Pessoa de Meia-Idade , Osteoartrite do Joelho/epidemiologia , Modelos de Riscos Proporcionais , Classe Social , Estados Unidos/epidemiologia , População Branca/estatística & dados numéricos , MulheresRESUMO
OBJECTIVES: Test the association between coronary heart disease (CHD) risk scores and neighborhood socioeconomic status (NSES) in a US nationally-representative sample and describe whether the association varies by gender and race/ethnicity. STUDY DESIGN: Cross-sectional study. METHODS: We use Health and Nutrition Examination Survey (NHANES) data from 1999 to 2004 linked with Census tract data. Multivariable regression models and propensity score adjusted models are employed to test the association between NSES and 10-year risk of CHD based on the Framingham Risk Score (FRS), adjusting for individual-level characteristics. RESULTS: An individual living in a neighborhood at the 75th percentile of NSES (high NSES) has, on average, a 10-year CHD risk that is 0.16 percentage points lower (95% Confidence Interval 0.16, 0.17) than a similar person residing in a neighborhood at the 25th percentile of NSES (low NSES). Race/ethnicity and gender were found to significantly modify the association between NSES and CHD risk: the association is larger in men than women and in whites than minorities. Propensity score models showed that findings on the main effects of NSES were robust to self-selection into neighborhoods. Similar results were observed between NSES and risk of cardiovascular disease events. CONCLUSIONS: NSES is significantly associated with CHD risk, and the relationship varies by gender and race/ethnicity.
Assuntos
Negro ou Afro-Americano/estatística & dados numéricos , Doença das Coronárias/etnologia , Hispânico ou Latino/estatística & dados numéricos , Características de Residência/estatística & dados numéricos , População Branca/estatística & dados numéricos , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos Nutricionais , Fatores de Risco , Distribuição por Sexo , Fatores Socioeconômicos , Estados Unidos/epidemiologiaRESUMO
PURPOSE: To determine the extent and consequences of part-time work in radiology. MATERIALS AND METHODS: A survey was mailed to 1,500 male and 1,500 female radiologists. Questions assessed part-time work and its effect on professional and family issues. The effects of education, radiology practice characteristics, organizational support, human resource practices, and family responsibilities on career and professional satisfaction were studied. RESULTS: Ten and a half percent of the radiologists surveyed--7.4% of the men and 30.2% of the women--were working part-time. The part-time radiologists reported earning 56.3% of the income earned by full-time radiologists and working 56.9% of the hours worked by their full-time counterparts, with disproportionately fewer benefits. Part-time private practice radiologists were significantly less likely to be partners. For academic radiologists, having worked part-time at any time was significantly associated with lower academic rank. CONCLUSION: The motivation for working part-time differed significantly according to gender and age. Benefits were disproportionate, and radiologists who had worked part-time were less likely to be partners or full professors.
Assuntos
Escolha da Profissão , Radiologia , Trabalho/estatística & dados numéricos , Adulto , Mobilidade Ocupacional , Feminino , Humanos , Renda , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários , Estados UnidosRESUMO
OBJECTIVES: To determine the effect of preprocedural education on mammography-related anxiety. MATERIALS AND METHODS: A total of 613 women undergoing mammography were surveyed regarding anxiety about the procedure and expected results. Half the study population watched an educational videotape and half watched an entertaining movie in the waiting room. RESULTS: Anxiety levels about results were significantly higher than anxiety levels about the procedure (P <.001). There was no difference in procedural or cancer anxiety levels among women shown the educational tape and those shown the entertaining movie. CONCLUSION: The fear of discovering breast cancer generates most of mammography-related anxiety. Preprocedural education did not affect procedural or cancer-related anxiety.
Assuntos
Ansiedade , Neoplasias da Mama/prevenção & controle , Neoplasias da Mama/psicologia , Mamografia/psicologia , Educação de Pacientes como Assunto , Adulto , Idoso , Feminino , Humanos , Pessoa de Meia-Idade , Inquéritos e QuestionáriosRESUMO
There is little information on the progression of peripheral arterial disease (PAD) over time. A series of 508 patients with a prior examination for PAD were contacted and brought in for follow-up to evaluate the natural history of PAD. A total of 85 patients were excluded because they had interventions in both limbs prior to their return visit. Progression was assessed in the remaining 423 patients for a total of 755 limbs, both quantitatively and qualitatively using six categories of PAD severity. There was a modest overall categorical progression of disease: 228 limbs (30.2%) displayed categorical progression, while 172 limbs (22.8%) improved over a 4.6-year average follow-up. Through analysis of quantitative change, it was determined that more quantitative progression occurred than was evident from categorical progression. Two of the three non-invasive tests employed, the ankle/brachial index (ABI) and posterior tibial peak forward flow velocity (peak PT), showed statistically significant progression during follow-up: mean ABI change = -0.019, 95% confidence interval (CI)= -0.031 to -0.007; mean peak PT change = -2.32 cm/s, 95% CI = -3.20 to -1.44. The toe/brachial index (TBI) also suggested progression: mean change= -0.013, but the 95% CI included no change. Standard scores (sum of the Z-scores for ABI, peak PT and TBI) were calculated. The standard score progressed approximately 0.34 units (standard deviations), p-value <0.001, over 4.6 years; or about 0.07 standard deviations per year. There were independent and statistically significant (p<0.05) associations between the rate of PAD progression (standard score change) and age, diabetes, classic ('Rose') intermittent claudication, moderate to severe PAD in the same limb, moderate to severe PAD in the contralateral limb and future therapeutic intervention. There were independent and suggestive associations (0.05Assuntos
Perna (Membro)/irrigação sanguínea
, Doenças Vasculares/fisiopatologia
, Idoso
, Tornozelo/irrigação sanguínea
, Braço/irrigação sanguínea
, Determinação da Pressão Arterial/métodos
, Angiopatias Diabéticas/fisiopatologia
, Progressão da Doença
, Feminino
, Humanos
, Claudicação Intermitente/fisiopatologia
, Estudos Longitudinais
, Masculino
, Fotopletismografia/métodos
, Fluxo Sanguíneo Regional/fisiologia
, Dedos do Pé/irrigação sanguínea
RESUMO
Using a national longitudinal survey of a representative sample of 1,256 adults, I assess the impact of the amount of household labor performed and its division within the household on men's and women's depression levels, adjusting for prior mental health status. I test two alternative explanations of the contributions of household labor and the division of household labor to gender differences in depression: differential exposure and differential vulnerability. The results indicate that men's lower contributions to household labor explain part of the gender difference in depression. Inequity in the division of household labor has a greater impact on distress than does the amount of household labor. Employment status moderates the effect of the division of labor on depression. Among those who describe themselves as keeping house, depression was lowest for those who performed 79.8 percent of housework. In contrast, for those employed full-time the minimum level of depression occurs at 45.8 percent of the household labor. Men report performing 42.3 percent of the housework in their homes compared to 68.1 percent reported by women. Thus, on average women are performing household labor beyond the point of maximum psychological benefit, whereas men are not. Social support mediates the effects of the division of household labor. The only gender difference in effects occurred among those who are married, for whom social support was associated with lower levels of depression for women than men.
Assuntos
Depressão/psicologia , Zeladoria , Casamento/psicologia , Adulto , Depressão/epidemiologia , Emprego/psicologia , Feminino , Indicadores Básicos de Saúde , Humanos , Controle Interno-Externo , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Escalas de Graduação Psiquiátrica , Análise de Regressão , Apoio Social , Fatores de Tempo , Estados Unidos/epidemiologiaRESUMO
Health research has failed to adequately explore the combination of social and biological sources of differences in men's and women's health. Consequently, scientific explanations often proceed from reductionist assumptions that differences are either purely biological or purely social. Such assumptions and the models that are built on them have consequences for research, health care and policy. Although biological factors such as genetics, prenatal hormone exposure and natural hormonal exposure as adults may contribute to differences in men's and women's health, a wide range of social processes can create, maintain or exacerbate underlying biological health differences. Researchers, clinicians and policy makers would understand and address both sex-specific and non-sex-specific health problems differently if the social as well as biological sources of differences in men's and women's health were better understood.
Assuntos
Nível de Saúde , Homens , Pesquisa/organização & administração , Caracteres Sexuais , Sexo , Saúde da Mulher , Adulto , Feminino , Política de Saúde , Necessidades e Demandas de Serviços de Saúde , Humanos , Masculino , Modelos Teóricos , Equipe de Assistência ao Paciente , Distribuição por Sexo , Sociologia Médica , Estados UnidosRESUMO
The WHO/Rose questionnaire has served as the epidemiologic and clinical standard in the assessment of leg pain in patients with peripheral arterial disease (PAD) for over three decades. However, the structure of this questionnaire does not allow assessment of leg-specific (i.e. right versus left) symptoms. We studied 508 patients aged 39-95 years (mean 68 years), initially referred for PAD non-invasive testing. A revised questionnaire, the San Diego Claudication Questionnaire, was administered which allowed determination of leg-specific symptoms and evaluated thigh and buttock as well as calf pain. Leg-specific symptoms were categorized into no pain, pain at rest, non-calf claudication, non-Rose calf claudication, and Rose claudication. At the same visit, the ankle brachial index, the toe brachial index, and peak posterior tibial flow velocity were measured by Doppler ultrasound and five categories of non-invasive results by type and severity of PAD were defined. Legs with previous intervention (Rx), surgery or angioplasty, were evaluated separately. Claudication was reported in 42% of no Rx legs and 50% of Rx legs; 40% of claudication was atypical (not Rose); 64% of no Rx and 81% of Rx legs had PAD by non-invasive testing, and 27% of affected legs had severe PAD. The correlation between the severity of symptoms and the severity of ipsilateral PAD in no Rx legs was r = -0.40, p < 0.001. In Rx legs, this correlation was somewhat less (r = 0.27, p < 0.001) due to more symptomatology at lesser degrees of PAD, suggesting reporting bias and/or more residual disease than evident from non-invasive testing. To our knowledge, these results provide the first comparison between a standardized assessment of leg pain and the severity of ipsilateral PAD by non-invasive testing.
Assuntos
Arteriosclerose/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Arteriosclerose/fisiopatologia , Arteriosclerose/terapia , Pressão Sanguínea/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Medição da Dor , Inquéritos e Questionários , Ultrassonografia DopplerRESUMO
The fatty acid derivative conjugated dienoic linoleate (CLA) has been shown to inhibit initiation and postinitiation stages of carcinogenesis in several experimental animal models. The goal of the present study was to determine the role of increasing levels of dietary CLA in mouse skin tumor promotion elicited by 12-O-tetradecanoylphorbol-13-acetate (TPA). Mice were fed control (no CLA) diet during initiation, then switched to diets containing 0.0%, 0.5%, 1.0%, or 1.5% (wt/wt) CLA during skin tumor promotion by TPA. Body weights of mice fed 0.5%, 1.0%, or 1.5% CLA were similar to each other but were significantly lower (p < 0.05) than weights of mice fed no CLA (0.0%) throughout promotion. A reduction in papilloma incidence was observed in mice fed 1.5% CLA from Weeks 8 to 24 compared with mice fed diets containing 0.0-1.0% CLA (p < 0.05). Twenty-four weeks after tumor promotion was begun, diets containing 1.0% and 1.5% CLA inhibited tumor yield (4.94 and 4.35 tumors/mouse, respectively) compared with diets without CLA (0.0% CLA, 6.65 tumors/mouse, p < 0.05) or 0.5% CLA (5.92 tumors/mouse, p < 0.05). These data indicate that CLA inhibits tumor promotion in a manner that is independent of its anti-initiator activity. Further studies are warranted in identifying cellular mechanisms that are likely to be involved with the antipromoter effects of CLA.
Assuntos
Gorduras Insaturadas na Dieta/uso terapêutico , Ácidos Linoleicos/uso terapêutico , Neoplasias Cutâneas/induzido quimicamente , Neoplasias Cutâneas/prevenção & controle , Acetato de Tetradecanoilforbol , Animais , Peso Corporal , Feminino , Ácido Linoleico , Camundongos , Papiloma/induzido quimicamente , Fatores de TempoRESUMO
A representative national sample of 2,031 adults aged 18 to 90 was interviewed by telephone in 1990. Results showed that men report better health than women, but that the gap closes with age. We argue that a gender difference in labor and lifestyles explains sex differences in perceived health across the life course: gender inequality in paid and unpaid work and the subjective experience of inequality disadvantage women, whereas lifestyle disadvantages men. Women are less likely to be employed, and are more likely to work part-time, have lower incomes and more economic hardship, and to do more unpaid domestic labor than men, all of which except domestic labor are associated with poor health. Domestic labor improves health, up to doing 60 percent of the housework. Women also have more distress and fewer subjective work rewards, both of which are associated with poor health. If women had the same levels of paid work, household income, economic hardship, work rewards, and distress as men, their health would equal that of men's and surpass it by age 59. Although we expected to find an overwhelming male disadvantage in lifestyle, we did not. Men are more likely than women to walk and to exercise strenuously, both of which are associated with good health. If women's labor and leisure-time physical activity equalled men's, women over the age of 54 would experience better health than men. Men's lifestyle disadvantage comes from their greater tendency to smoke and to be overweight, both of which are associated with poor health.
Assuntos
Emprego/psicologia , Nível de Saúde , Estilo de Vida , Adolescente , Adulto , Fatores Etários , Idoso , Estudos Transversais , Exercício Físico , Feminino , Indicadores Básicos de Saúde , Zeladoria , Humanos , Controle Interno-Externo , Satisfação no Emprego , Masculino , Pessoa de Meia-Idade , Obesidade , Análise de Regressão , Autorrevelação , Fatores Sexuais , Fumar , Classe Social , Estresse PsicológicoRESUMO
One of the continuing paradoxes facing social epidemiologists concerns sex differences in morbidity and mortality. Although women live longer than men, they apparently get sick more. We hypothesize that women's higher morbidity levels result from less paid work and lower wages combined with more hours spent in household labor, child care, and helping others, and fewer hours of leisure and sleep. Men and women hold different social roles; men hold most of the highly rewarding roles. We operationalize social roles as time commitments to various role-related activities. This approach provides interval-level measures such as time spent in caring for children instead of simple dichotomies such as parent/nonparent. We find that when gender differences in social roles are controlled, being male is associated with poorer health than being female. We conclude that if gender roles were more equal, women would experience better health than men, more consistent with their greater longevity.
Assuntos
Nível de Saúde , Papel (figurativo) , Fatores Sexuais , Adulto , Emprego , Feminino , Seguimentos , Comportamento de Ajuda , Humanos , Atividades de Lazer , Longevidade , Masculino , Pessoa de Meia-Idade , Modelos Psicológicos , Morbidade , Inquéritos e Questionários , Fatores de Tempo , Estados Unidos/epidemiologia , TrabalhoRESUMO
Androgen metabolism and the regulation of rat ventral prostate cell proliferation and secretory function were examined during sexual maturation. Changes in acid phosphatase (AP) characteristics were measured as a marker of androgen-dependent prostatic secretory function. In immature (21-day-old) rats, total AP activity per cell was low (14.2 +/- 1.3 mol p-nitrophenol phosphate hydrolysed/h per mg DNA); it increased threefold as the weight, protein and DNA contents of the prostate increased to adult (65-day) levels. This corresponded with significant (P less than 0.001) increases in the staining intensities of three of the four bands of secretory AP on isoelectric focusing gels. The extent of inhibition of AP by tartrate decreased at the same time. Secretory AP is known to be relatively tartrate-resistant. The changes in AP activity occurred after prostatic 5 alpha-dihydrotestosterone (5 alpha-DHT) levels increased from 4.6 +/- 0.7 pmol/mg DNA (21 days) to reach a peak of 17.6 +/- 2.3 pmol/mg DNA at 58 days. Prostatic 5 alpha-DHT concentrations were always higher than testosterone levels. Prostatic 5 alpha-androstane-3 alpha,17 beta-diol (3 alpha-Adiol) levels were lower than 5 alpha-DHT levels except on day 58 when levels peaked dramatically at 26.2 +/- 5.5 pmol/mg DNA. Changes in prostatic 5 alpha-DHT and 3 alpha-Adiol levels corresponded with changes in 5 alpha-reductase and 3 alpha-hydroxysteroid oxidoreductase (3 alpha-HSOR) activities. The oxidative reaction of 3 alpha-HSOR was approximately fourfold higher than the reductive reaction, indicating a preference for the formation of 5 alpha-DHT. The plasma levels of testosterone, 5 alpha-DHT and 3 alpha-Adiol cannot account for their respective prostatic levels, indicating the importance of the steroid-metabolizing enzymes in regulating intracellular androgen levels. Changes in the AP characteristics could be correlated with the androgen status of the prostate.
Assuntos
Fosfatase Ácida/metabolismo , Androgênios/metabolismo , Próstata/crescimento & desenvolvimento , Maturidade Sexual , Androstano-3,17-diol/metabolismo , Animais , Di-Hidrotestosterona/metabolismo , Masculino , Tamanho do Órgão , Próstata/enzimologia , Próstata/metabolismo , Ratos , Ratos Endogâmicos , Testosterona/metabolismoRESUMO
Testosterone is a known estrogen precursor especially in postmenopausal women. Tamoxifen, an anti-estrogen, is used in the treatment of women with breast cancer in whom metastatic disease has been demonstrated. The action of Tamoxifen is thought to be to occupy the intracellular estrogen receptor sites in target tissues and thus block the action of the biologically active estrogen, estradiol. Effects of Tamoxifen on the production and metabolism of hormones have been postulated. We studied the kinetics of testosterone metabolism by the constant infusion of 3H-testosterone in six postmenopausal women with breast cancer prior to and during Tamoxifen therapy. The Tamoxifen did not produce any significant change in the metabolic clearance rate, the plasma concentration or the calculated blood production rate of testosterone. The only significant alteration in the conversion ratio of testosterone to metabolites was the reduction (p less than 0.02) in conversion to 5 alpha-dihydrotestosterone. A significant reduction in the plasma concentrations (p less than 0.05) of dehydroepiandrosterone and of luteinizing hormone (p less than 0.02) was found. Other steroid and peptide hormones did not show any significant changes. We conclude that Tamoxifen therapy has very little effect on the kinetics of testosterone metabolism in postmenopausal women with metastatic breast cancer.
Assuntos
Neoplasias da Mama/metabolismo , Menopausa/efeitos dos fármacos , Tamoxifeno/farmacologia , Testosterona/metabolismo , Idoso , Desidroepiandrosterona/metabolismo , Di-Hidrotestosterona/metabolismo , Estradiol/farmacologia , Feminino , Humanos , Cinética , Hormônio Luteinizante/metabolismo , Taxa de Depuração Metabólica , Pessoa de Meia-Idade , Receptores de Estrogênio/efeitos dos fármacos , Testosterona/administração & dosagemRESUMO
Psychometric examination of a group of diabetic patients and a group of age-matched controls failed to provide evidence of impaired intellectual functioning in the diabetic group. The cognitive status of the diabetics was not related to the duration of the illness, the age at diagnosis, or clinical ratings of peripheral or autonomic neuropathy.
Assuntos
Neuropatias Diabéticas/psicologia , Adolescente , Adulto , Fatores Etários , Doenças do Sistema Nervoso Autônomo/psicologia , Cognição , Neuropatias Diabéticas/fisiopatologia , Feminino , Humanos , Inteligência , Masculino , Memória , Pessoa de Meia-Idade , Condução Nervosa , Fatores de TempoRESUMO
A descriptive study of the psychiatric findings in 50 insulin--dependent diabetics is presented. Among the symptoms found were a marked reduction in energy level, increased fatigue and irritability, depression, and delayed psychosexual maturation. Diabetes mellitus is commonly considered to be a disease that, if properly controlled, allows the patient to lead a relatively normal life. We found, however, that these symptoms often made the patients' lives uncomfortable, reduced their functional capacity, disrupted their family life, and disturbed the adolescence of those who were affected at an early age.
Assuntos
Diabetes Mellitus Tipo 1/psicologia , Adolescente , Adulto , Sintomas Afetivos/etiologia , Glicemia/metabolismo , Peso Corporal , Transtornos Cognitivos/etiologia , Diabetes Mellitus Tipo 1/sangue , Escolaridade , Fadiga , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Desenvolvimento Psicossexual , Fatores SexuaisRESUMO
In a previous publication, we presented evidence of slowed conduction speed in the central nervous systems of insulin-dependent diabetic subjects, manifest in a delay in the latency of the brainstem auditory-evoked response (BAER). In this article, we present the results of a multivariate study conducted on a larger sample of 50 insulin-dependent, adult diabetic subjects. The purpose of the study was to determine some of the functional correlates of the BAER delay; each patient received an assessment of the BAER, the late auditory-evoked potential (EP), the conduction velocities of the sural, median, and common peroneal nerves, and intellectual and emotional function, in addition to neurologic and audiologic examinations. A nondiabetic control group was matched with the diabetic group as to age and sex. The results indicated a delay in the latency of wave V, and in interpeak latencies I-III and I-V, of the BAER. The most reliable effect was on interpeak latency I-V; this suggested that the locus of the delay was in the central auditory projections, rather than in the acoustic nerve. In addition, BAER waves I, II, III, IV, and V were reduced in amplitude, as was the N1 component of the late auditory EP; the most reliable reduction in amplitude was in wave V. The effect was similar in magnitude for males and females, relative to their counterparts in the control group. The slowed BAER response appeared early in the disease and was not related to the duration of insulin treatment. It was correlated with a chronic loss of energy and the presence of sexual dysfunction.(ABSTRACT TRUNCATED AT 250 WORDS)
Assuntos
Encéfalo/fisiopatologia , Diabetes Mellitus/fisiopatologia , Condução Nervosa , Adolescente , Adulto , Envelhecimento , Doenças do Sistema Nervoso Autônomo/fisiopatologia , Glicemia/metabolismo , Tronco Encefálico/fisiopatologia , Depressão/fisiopatologia , Diabetes Mellitus/sangue , Diabetes Mellitus/psicologia , Neuropatias Diabéticas/fisiopatologia , Potenciais Evocados Auditivos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Caracteres Sexuais , Disfunções Sexuais Fisiológicas/fisiopatologia , Fatores de TempoRESUMO
The constant infusion technique was used to study the kinetics of dehydroepiandrosterone sulfate (DHEAS) metabolism in normal young men and women. The metabolic clearance rates (MCR) (means +/- SEM) for normal young men and women were 15.2 +/- 1.7 1/24 h (8.2 +/- 0.7 1/m2/24 h) and 11.8 +/- 0.8 1/24 h (7.3 +/- 0.4 1/m2/24 h) respectively. Coupled with the plasma levels of 5.07 +/- 1.95 and 4.02 +/- 0.57 mumole/L the resulting blood production rates were 76.7 +/- 25.7 and 48.0 +/- 9.4 mumole/24 h for men and women respectively. The conversion ratios for the conversion of DHEAS to dehydroepiandrosterone (DHEA) were 0.006 for men and 0.004 for women. Because of the high metabolic clearance rates for DHEA relative to those for DHEAS and the high production rates of DHEAS most of the DHEA produced per day can arise from DHEAS.
Assuntos
Desidroepiandrosterona/análogos & derivados , Adulto , Desidroepiandrosterona/sangue , Desidroepiandrosterona/metabolismo , Sulfato de Desidroepiandrosterona , Feminino , Humanos , Masculino , Taxa de Depuração Metabólica , Valores de ReferênciaRESUMO
To study androgen-mediated differentiation in the rat ventral prostate, we separated the two principal cell types (epithelial and stromal) derived from prostates of immature and mature rats on two continuous Percoll gradients. Cells were immediately placed in culture medium. Testosterone metabolism by the two prostatic cell types was evaluated using [3H]testosterone and quantifying the formation of 5 alpha-[3H]dihydrotestosterone (5 alpha-DHT) and 5 alpha-[3H]androstane-(3 alpha or 3 beta), 17 beta-diols. In epithelial cells from both immature and mature rat prostates the major testosterone metabolites were 5 alpha-DHT and 5 alpha-androstane-3 alpha, 17 beta-diol. Stromal cells metabolized less testosterone than did the epithelial cells. Differences in the relative levels of the various metabolites were observed for the two age groups. To examine in more detail the changes in testosterone metabolism observed in vitro both types of cells and unfractionated cells from immature and mature rat prostates were assayed for testosterone 5 alpha-reductase (using testosterone as substrate) and 3 alpha-hydroxysteroid dehydrogenase (using 5 alpha-DHT as substrate) activities (expressed as pmol substrate reduced/min per 10(6) cells). In immature rats both 5 alpha-reductase and 3 alpha-hydroxysteroid dehydrogenase activities were localized in the epithelial cell fraction (17 and 52 respectively); stromal cells showed lower 5 alpha-reductase and 3 alpha-hydroxysteroid dehydrogenase activity (4 and 4). Relative to epithelial cells from immature rats epithelial cells from mature rats showed a decrease in 5 alpha-reductase (7) and an increase in 3 alpha-hydroxysteroid dehydrogenase (160) activity while stromal 5 alpha-reductase showed little change (3) and 3 alpha-hydroxysteroid dehydrogenase increased to 22.(ABSTRACT TRUNCATED AT 250 WORDS)
Assuntos
3-Hidroxiesteroide Desidrogenases/metabolismo , 3-Oxo-5-alfa-Esteroide 4-Desidrogenase/metabolismo , Oxirredutases/metabolismo , Próstata/enzimologia , Maturidade Sexual , 3-alfa-Hidroxiesteroide Desidrogenase (B-Específica) , Animais , Diferenciação Celular , Células Cultivadas , Masculino , Próstata/citologia , Ratos , Ratos EndogâmicosRESUMO
To further characterize the androgen dependence of prostatic acid phosphatase (AP), the isoelectric focusing patterns of enzyme activity have been examined for normal and castrated adult rats and for rats receiving androgen injections. Isoelectric focusing was performed in polyacrylamide gels over the pH range 4-8. Naphthyl phosphate was used as substrate for staining. For normal rats there was a single lysosomal band (isoelectric point(pI) = 7.35 +/- 0.04), four closely migrating secretory bands (pI = 5.96-5.63), and an androgen-dependent band (pI = 6.37 +/- 0.05) which as yet has not been identified as either lysosomal or secretory. Following castration the secretory bands decreased significantly in staining intensity, the androgen-dependent band disappeared, and two new lysosomal bands (pI's = 7.13 +/- 0.03 and 7.00 +/- 0.03) appeared. With androgen replacement the latter two bands disappeared, the androgen-dependent band reappeared, and the secretory bands increased in staining intensity but with the most anodic of the four appearing before the others. This suggests that it could be a precursor to the others. The isoelectric focusing patterns of AP activity appear to be a better method of assessing the androgen status of the prostate than are the previously used parameters, namely, enzyme specific activity, degree of inhibition by tartrate, and polyacrylamide gel electrophoretic pattern.