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1.
Diabet Med ; 34(4): 531-538, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-27973745

RESUMEN

AIM: To investigate the association between changes in oestradiol and follicle-stimulating hormone levels during the menopausal transition and incident diabetes. METHODS: We followed 1407 pre-menopausal women, aged 42-52 years at baseline, who experienced natural menopause, from baseline to the 12th annual follow-up visit in the Study of Women's Health Across the Nation (SWAN). Diabetes was defined based on fasting glucose level, medication use and self-report of physician diagnosis. Cox proportional hazards regression was used to evaluate the associations of incident diabetes with three components of the rate of change in hormones: the intercept (pre-menopausal levels) and two piece-wise slopes representing change during the early and late transition, respectively. RESULTS: During 15 years of follow-up, 132 women developed diabetes. After adjusting for potential confounders, a higher oestradiol intercept, but not its rate of change, was borderline significantly associated with lower risk of diabetes [hazard ratio for an interquartile range increase (75.2 pmol/L) 0.53, 95% CI 0.27-1.06]. For follicle-stimulating hormone, a greater rate of increase in the early transition, but not the intercept or late transition, was significantly associated with lower risk of diabetes [hazard ratio for an interquartile range increase (5.9 IU/L/year) 0.31, 95% CI 0.10-0.94]. CONCLUSIONS: Lower pre-menopausal oestradiol levels and a slower rate of follicle-stimulating hormone change during the early transition were associated with higher risk of developing diabetes. Given that obesity plays an important role in diabetes risk and in the levels and changes in oestradiol and follicle-stimulating hormone over the menopausal transition, weight control in earlier mid-life is important to prevent future diabetes development.


Asunto(s)
Diabetes Mellitus Tipo 2/metabolismo , Estradiol/metabolismo , Hormona Folículo Estimulante/metabolismo , Menopausia/metabolismo , Adulto , Diabetes Mellitus Tipo 2/epidemiología , Femenino , Estudios de Seguimiento , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Obesidad/epidemiología , Obesidad/metabolismo , Modelos de Riesgos Proporcionales , Riesgo , Estados Unidos/epidemiología
2.
BJOG ; 121(12): 1564-73, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24735184

RESUMEN

OBJECTIVE: Previous studies describing menses duration and heaviness of flow during the menopausal transition (MT) have been short in duration and limited to white women. We estimated the frequency of and risk factors for prolonged bleeding, spotting and heavy bleeding during the MT in an ethnically diverse population. DESIGN: Prospective community-based cohort study. SETTING USA: southeastern Michigan, northern California and Los Angeles, California. POPULATION: A total of 1320 midlife women who participated in the Study of Women's Health Across the Nation (SWAN) Menstrual Calendar Substudy. Participants included African-American, white, Chinese, and Japanese women. METHODS: Women completed daily menstrual calendars from 1996 to 2006, and provided information on hormone therapy, smoking and physical activity. Annual measures included height and weight. Kaplan-Meier survival analysis and multivariable regression were used to analyse the data. MAIN OUTCOME MEASURES: Menses of 10+ days, spotting of 6+ days, heavy bleeding of 3+ days. RESULTS: At least three occurrences of menses 10+ days was reported by 77.7% (95% confidence interval [95% CI] 56.7-93.2), of 6+ days of spotting by 66.8% (95% CI 55.2-78.0) and of 3+ days of heavy bleeding by 34.5% (95% CI 30.2-39.2) of women. Menses of 10+ days, 6+ days of spotting, and 3+ days of heavy bleeding were associated with MT stage, uterine fibroids, hormone use and ethnicity. Body mass index was associated with 3+ days of heavy bleeding. CONCLUSIONS: These data provide clinicians and women with important information about the expected frequency of prolonged and heavy bleeding and spotting during the menopausal transition that may facilitate clinical decision making.


Asunto(s)
Menopausia/etnología , Menorragia/etnología , Menstruación/etnología , Adulto , Negro o Afroamericano , Asiático , Femenino , Estudios de Seguimiento , Humanos , Estimación de Kaplan-Meier , Menopausia/fisiología , Menstruación/fisiología , Persona de Mediana Edad , Análisis Multivariante , Estudios Prospectivos , Autoinforme , Estados Unidos/epidemiología , Población Blanca
3.
Diabet Med ; 30(12): 1433-41, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23659546

RESUMEN

AIMS: The prevalence of hepatic steatosis may differ between post-menopausal African-American women and non-Hispanic white women and by sex hormone binding globulin level. We examined prevalence of hepatic steatosis by race/ethnicity and associations with sex hormone binding globulin. METHODS: Participants included post-menopausal women who underwent hepatic ultrasound (n = 345) at the Michigan site of the Study of Women's Health Across the Nation, a population-based study. We examined hepatic steatosis prevalence by race/ethnicity and used logistic regression models to calculate the odds of hepatic steatosis with race/ethnicity and sex hormone binding globulin, after adjustment for age, alcohol use, waist circumference, high density lipoprotein cholesterol, triglycerides, systolic blood pressure and use of medications reported to lower intrahepatic fat. RESULTS: Fewer African-American women than non-Hispanic white women had hepatic steatosis (23 vs. 36%, P = 0.01). African-American women had lower triglyceride and low-density lipoprotein cholesterol levels, but higher blood pressure and follicle-stimulating hormone levels (P < 0.05). In the optimal-fitting multivariable models, women in the highest tertile of sex hormone binding globulin (60.2-220.3 nmol/l) had a lower odds of hepatic steatosis (odds ratio 0.43, 95% CI 0.20-0.93) compared with women in the lowest tertile of sex hormone binding globulin (10.5-40.3 nmol/l). There was an interaction between race/ethnicity and medication use whereby non-Hispanic white women using medications had three times higher odds of hepatic steatosis compared with African-American women not using medications (odds ratio 3.36, 95% CI 1.07-10.58). Interactions between race/ethnicity and other variables, including sex hormone levels, were not significant. CONCLUSIONS: Hepatic steatosis on ultrasound may be more common in post-menopausal non-Hispanic white women than African-American women and was associated with lower levels of sex hormone binding globulin.


Asunto(s)
Negro o Afroamericano , Hígado Graso/etnología , Hormona Folículo Estimulante/sangre , Globulina de Unión a Hormona Sexual/metabolismo , Población Blanca , Salud de la Mujer , Adulto , Negro o Afroamericano/etnología , Presión Sanguínea , LDL-Colesterol/sangre , Estudios de Cohortes , Hígado Graso/sangre , Hígado Graso/epidemiología , Femenino , Humanos , Michigan , Persona de Mediana Edad , Oportunidad Relativa , Posmenopausia/sangre , Prevalencia , Triglicéridos/sangre , Estados Unidos/epidemiología , Población Blanca/etnología , Salud de la Mujer/etnología
5.
Domest Anim Endocrinol ; 71: 106389, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31731251

RESUMEN

Thyroid disease is common in cats, but little is known about the biologic variability of serum thyroid hormone concentrations and its impact on diagnostic utility in either healthy cats or cats with thyroid disease. The purpose of this study was to determine the biological variation, index of individuality, and reference change values for thyroid hormones and thyroid-stimulating hormone (TSH) in clinically healthy cats. Serum samples for analysis of total thyroxine (T4), triiodothyronine (T3), free T4 by dialysis, and TSH were obtained weekly for 6 wk from 10 healthy cats, then frozen until single-batch analyzed. Data were evaluated for outliers, and we determined the CV within individual cats (CVI) and between individual cats (CVG) for each hormone and the variation between duplicates or analytical variation (CVA). The index of individuality and reference change values for each hormone were then calculated. Serum concentrations of total T4, free T4, T3, and TSH all showed greater variation between cats (CVG) than within cats (CVI). Total and free T4 had an intermediate index of individuality (1.1 and 1.2, respectively), suggesting that these hormones would be best evaluated by a combination of their population-based reference intervals and reference change values. Serum TSH concentrations had high index of individuality (1.8), suggesting this hormone would be best evaluated with reference change values rather than the population-based reference interval. Total T3 also had a high calculated index of individuality (1.8); however, T3 had high ratio of analytical variation (CVA) to within cat variation (CVI), so RCV could not be accurately calculated. This study demonstrates that clinically normal cats show considerable interindividual biological variation in serum thyroid hormone and TSH concentrations, whereas the intraindividual variability in hormone concentrations is much narrower. This suggests that for all serum thyroid hormones, but especially serum TSH and T3 concentrations, comparing individual cat's hormone results to a population-based reference interval may be misleading, especially in those with early or subclinical thyroid disease. Clinicians might improve the diagnosis of feline thyroid disease by establishing baseline concentrations of T4, free T4, T3, and TSH for individual cats (ideally when healthy) and applying reference change values to subsequent measurements.


Asunto(s)
Gatos/sangre , Hormonas Tiroideas/sangre , Tirotropina/sangre , Tiroxina/sangre , Triyodotironina/sangre , Animales , Femenino , Masculino , Valores de Referencia , Factores de Tiempo
6.
Hum Reprod ; 24(9): 2276-85, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19520711

RESUMEN

BACKGROUND: In this study, levels and rates of change in total testosterone (T), sex hormone-binding globulin (SHBG) and free androgen index (FAI) were related to chronological age and to the final menstrual period (FMP) as an indicator of ovarian aging. METHODS: Data were annually acquired over a 15-year period in 629 women of the Michigan Bone Health and Metabolism Study cohort. Data were censored for hormone therapy use. Endogenous androgen patterns over time were described with stochastic processes and bootstrapping. RESULTS: With ovarian aging, T levels rose from a mean of 18 ng/dl commencing 10 years prior to the FMP to 27 ng/dl at the FMP. Over the 20-year period encompassing the FMP, modeled mean SHBG levels changed from 58 to 34 nM and the FAI ratio increased from 1.6 to 2.9 in a non-linear manner. With chronological aging, total T levels increased (P < 0.0001) from 43 to 50 years, but not thereafter. SHBG declined steadily with age with a modestly greater rate of change between 49 and 54 years. The FAI increased from 1.3 to 2.5 from 34 to 58 years. CONCLUSIONS: T increased from approximately age 40 until the FMP whereas SHBG had rate of change patterns reflecting both chronological and ovarian aging components. These data provide new insight into the endogenous androgen patterns at mid-life.


Asunto(s)
Envejecimiento/fisiología , Andrógenos/metabolismo , Ovario/crecimiento & desarrollo , Globulina de Unión a Hormona Sexual/metabolismo , Testosterona/metabolismo , Adulto , Femenino , Humanos , Posmenopausia
7.
Minerva Ginecol ; 61(6): 469-81, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19942835

RESUMEN

Reproductive hormones have long been thought to have a significant impact on brain function in humans. Estrogens, progestins and androgens have all been shown to have effects on nerve growth and function in vitro. The neurofunctional domains of cognition, mood and sleep are now receiving increased study to determine both the relationship of endogenous sex steroids through the menopausal transition and the effect of menopausal hormone therapy on these complex functions. All three domains are the source of frequent concern in midlife women, but the relative contribution of ovarian versus somatic aging is only now being untangled. Cognitive function has been most extensively studied, with mixed results in both observational studies and clinical trials, largely due to the remarkably complex aspects of human cognition requiring extensive and targeted testing of specific components. Both mood and sleep disorders have been associated with the menopausal transition, but observed effects appear modest. To date, clinical trial data are insufficient to support the use of hormone therapy specifically for the prevention or treatment of cognitive, mood or sleep disorders in midlife women.


Asunto(s)
Encéfalo/fisiología , Hormonas Esteroides Gonadales/fisiología , Menopausia/fisiología , Premenopausia/fisiología , Adulto , Afecto/efectos de los fármacos , Afecto/fisiología , Anciano , Anciano de 80 o más Años , Animales , Ensayos Clínicos como Asunto , Cognición/efectos de los fármacos , Cognición/fisiología , Trastornos del Conocimiento/tratamiento farmacológico , Trastornos del Conocimiento/etiología , Estudios de Cohortes , Depresión/tratamiento farmacológico , Depresión/etiología , Estrógenos/efectos adversos , Femenino , Hormonas Esteroides Gonadales/farmacología , Hormonas Esteroides Gonadales/uso terapéutico , Terapia de Reemplazo de Hormonas , Humanos , Masculino , Menopausia/psicología , Metaanálisis como Asunto , Persona de Mediana Edad , Premenopausia/psicología , Sueño/efectos de los fármacos , Sueño/fisiología , Trastornos Intrínsecos del Sueño/tratamiento farmacológico , Trastornos Intrínsecos del Sueño/etiología , Accidente Cerebrovascular/inducido químicamente , Accidente Cerebrovascular/prevención & control , Trombofilia/inducido químicamente
8.
J Clin Endocrinol Metab ; 93(5): 1711-21, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-18285413

RESUMEN

CONTEXT: Reproductive hormones are incompletely characterized during the menopause transition (MT). HYPOTHESIS: Increased anovulation and decreased progesterone accompany progress through the MT. DESIGN: The Daily Hormone Study (DHS) of the Study of Women's Health Across the Nation (SWAN) included 848 women aged 43-53 yr at baseline who collected daily urine for one cycle or up to 50 d annually for 3 yr. MAIN OUTCOME MEASURES: LH, FSH, estrone conjugates, and pregnanediol glucuronide levels were assessed. Cycles were classified by presumed luteal (ovulatory) status and bleeding. Hormones were related to time in study, age, menopausal status, and selected variables. RESULTS: Ovulatory-appearing cycles declined from 80.9% at baseline to 64.7% by the third assessment (H3). Cycles presumed anovulatory and not ending with bleeding by 50 d (anovulatory/nonbleeding) increased from 8.4 to 24% by H3 and were associated with progress to early perimenopause [odds ratio (OR) = 2.66; confidence interval (CI) = 1.17-6.04] or late perimenopause (OR = 56.21; CI = 18.79-168.12; P < 0.0001), African-American ethnicity (OR = 1.91; CI = 1.06-3.43), and less than high school education (OR = 3.51; CI = 1.62-7.62). Anovulatory cycles ending with bleeding remained at about 10% from baseline to H3; compared with ovulatory cycles, they were associated with obesity (OR = 4.68; CI = 1.33-16.52) and more than high school education (OR = 2.12; CI = 1.22-3.69; P = 0.02). Serum estradiol in both the highest and lowest categories was associated with anovulatory/nonbleeding collections. Pregnanediol glucuronide decreased 6.6% for each year on study. Insulin sensitivity measures did not relate strongly to menstrual cycle hormones. CONCLUSIONS: Anovulation without bleeding represents progression of the MT. A small but detectable decrease in luteal progesterone excretion occurs as women progress through the MT.


Asunto(s)
Fase Luteínica/fisiología , Menopausia/fisiología , Adulto , Pueblo Asiatico , Índice de Masa Corporal , Estrona/sangre , Femenino , Hormona Folículo Estimulante/sangre , Humanos , Hormona Luteinizante/sangre , Persona de Mediana Edad , Pregnanodiol/análogos & derivados , Pregnanodiol/sangre , Población Blanca
9.
Artículo en Inglés | MEDLINE | ID: mdl-30032277

RESUMEN

CONTEXT: Anti-Müllerian hormone based (AMH) age at menopause predictions remain cumbersome due to predictive inaccuracy. OBJECTIVE: To perform an Individual Patient Data (IPD) meta-analysis, regarding AMH based menopause prediction. DATA SOURCES: A systematic literature search was performed using PubMed, Embase and Cochrane databases. STUDY SELECTION: Prospective cohort studies regarding menopause prediction using serum AMH levels were selected by consensus discussion. DATA SELECTION: Individual cases were included if experiencing a regular cycle at baseline. Exclusion criteria were hormone use and gynecological surgery. DATA SYNTHESIS: 2596 women were included, 1077 experienced menopause. A multivariable Cox regression analysis assessed time to menopause (TTM) using age and AMH. AMH predicted TTM, however, added value on top of age was poor (age alone C-statistic 84%; age + AMH HR 0.66 95% CI 0.61-0.71, C-statistic 86%). Moreover, the capacity of AMH to predict early (≤45 years) and late menopause (≥55 years) was assessed. An added effect of AMH was demonstrated for early menopause (age alone C-statistic 52%; age + AMH HR 0.33, 95% CI 0.24-0.45, C-statistic 80%). A Weibull regression model calculating individual age at menopause revealed that predictive inaccuracy remained present and increased with decreasing age at menopause. Lastly, a check of non-proportionality of the predictive effect of AMH demonstrated a reduced predictive effect with increasing age. CONCLUSION: AMH was a significant predictor of TTM and especially of time to early menopause. However, individual predictions of age at menopause demonstrated a limited precision, particularly when concerning early age at menopause, making clinical application troublesome.

10.
J Vet Intern Med ; 31(3): 723-729, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28382700

RESUMEN

BACKGROUND: Thyroid cysts are rare in cats and poorly documented. OBJECTIVES: To report distinguishing clinical features and treatment responses of cats with thyroid cysts. ANIMALS: Forty client-owned cats. METHODS: Retrospective review of medical records for cats with thyroid cysts confirmed by scintigraphy, ultrasound, magnetic resonance imaging, or necropsy at 4 referral centers between 2005 and 2016. Signalment, clinical findings, diagnostic testing, treatment, and outcome were recorded. RESULTS: Cats ranged in age from 8 to 20 years with no apparent breed or sex predilection. 37 of 40 (93%) cats were hyperthyroid (duration, 1-96 months). Clinical findings included palpable neck mass (40/40, 100%), weight loss (15/40, 38%), dysphagia (8/40, 20%), decreased appetite (5/40, 13%), and dyspnea (4/40, 10%). Cysts were classified as small (≤8 cm3 ) in 16 (40%) and large (>8 cm3 ) in 24 (60%) cats. Of 25 cats treated with radioiodine, hyperthyroidism resolved in 23 (92%), whereas thyroid cysts resolved in 12 (50%). Radioiodine treatment resolved small cysts in 8 of 13 (62%) cats and large cysts in 4 of 11 (36%) cats. Eight cats, including 2 euthyroid cats, underwent thyroid-cystectomy; 3 with bilateral thyroid involvement were euthanized postoperatively for hypocalcemia. Excised cystic thyroid masses were identified as cystadenoma (4) and carcinoma (4). CONCLUSIONS AND CLINICAL IMPORTANCE: Thyroid cysts are encountered in hyperthyroid and euthyroid cats with benign and malignant thyroid tumors. Radioiodine treatment alone inconsistently resolved thyroid cysts. Thyroid-cystectomy could be considered in cats with unilateral thyroid disease or when symptomatic cysts persist despite successful radioiodine treatment of hyperthyroidism.


Asunto(s)
Enfermedades de los Gatos/epidemiología , Neoplasias de la Tiroides/veterinaria , Animales , Carcinoma/epidemiología , Carcinoma/veterinaria , Enfermedades de los Gatos/sangre , Enfermedades de los Gatos/diagnóstico por imagen , Enfermedades de los Gatos/patología , Gatos , Cistoadenoma/epidemiología , Cistoadenoma/veterinaria , Quistes/epidemiología , Quistes/veterinaria , Femenino , Radioisótopos de Yodo , Imagen por Resonancia Magnética/veterinaria , Masculino , New York/epidemiología , Cintigrafía/veterinaria , Estudios Retrospectivos , Neoplasias de la Tiroides/epidemiología , Tiroxina/sangre , Tiroxina/metabolismo , Tomografía Computarizada por Rayos X/veterinaria
11.
J Vet Intern Med ; 31(2): 326-334, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28158908

RESUMEN

BACKGROUND: Radioiodine (131 I) is effective treatment for hyperthyroidism in cats, but optimal dose to restore euthyroidism without inducing hypothyroidism is unclear. Treatment-induced hypothyroidism can lead to azotemia and reduced duration of survival. OBJECTIVE: To compare efficacy and short-term outcomes of low-dose 131 I versus higher, standard-dose 131 I as treatment for hyperthyroidism. ANIMALS: A total of 189 client-owned cats undergoing 131 I treatment for mild-to-moderate hyperthyroidism (serum T4 ≥ 4.0 µg/dL and <13.0 µg/dL). METHODS: Prospective, nonrandomized, cohort study comparing treatment with either low-dose (2 mCi, n = 150) or standard-dose (4 mCi, n = 39) 131 I. Serum T4 , thyroid-stimulating hormone (TSH), and creatinine concentrations were measured after 1, 3, and 6 months to determine persistent hyperthyroidism, overt hypothyroidism (low T4 , high TSH), subclinical hypothyroidism (normal T4 , high TSH), and azotemia. RESULTS: There was no significant difference in prevalence of cats with persistent hyperthyroidism between standard- and low-dose treatment groups at 3 (0% versus 5.3%; P = .34) and 6 (0% versus 3.3%; P = .51) months. Overt (18% versus 1%; P = .0005) or subclinical (46% versus 21%; P = .004) hypothyroidism was more common in cats at 6 months after standard-dose 131 I. No difference in incidence of azotemia existed between groups, but cats treated with standard-dose 131 I had higher creatinine concentrations (P < .05) and higher percent rises in creatinine (P < .0001). CONCLUSIONS AND CLINICAL IMPORTANCE: Low-dose 131 I is safe and effective for cats with mild-to-moderate hyperthyroidism, as evidenced by a cure rate of >95% with reduced frequency of iatrogenic hypothyroidism and azotemia.


Asunto(s)
Enfermedades de los Gatos/radioterapia , Hipertiroidismo/veterinaria , Radioisótopos de Yodo/uso terapéutico , Animales , Azotemia/etiología , Azotemia/veterinaria , Gatos , Creatinina/sangre , Femenino , Hipertiroidismo/radioterapia , Hipotiroidismo/etiología , Hipotiroidismo/veterinaria , Radioisótopos de Yodo/efectos adversos , Masculino , Estudios Prospectivos , Tirotropina/sangre , Tiroxina/sangre , Resultado del Tratamiento
12.
J Vet Intern Med ; 19(3): 303-14, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-15954543

RESUMEN

S-adenosylmethionine (SAMe), an important hepatic metabolite and glutathione (GSH) donor, has been studied mechanistically in vitro, in humans with clinical liver disease, and in experimental animal models of liver disease. Collective findings encourage its therapeutic use in necroinflammatory and cholestatic liver disorders. A chronic longitudinal study (pre- and posttreatment parameters compared) was undertaken with 15 clinically healthy cats given a stable 1,4-butanedisulfonate (S'S isomer) SAMe salt (enteric coated tablets providing 180 mg SAMe), dosage 48 mg/kg PO q24h, on an empty stomach for 113 days. Routine physical and clinicopathologic assessments, red blood cell (RBC) osmotic fragility, liver function and histology, hepatic concentrations of reduced GSH (RGSH) and its oxidized disulfide form (GSSG), protein, glycogen, and deoxyribonucleic acid, GSH concentrations in RBCs, total bile acids in serum and bile, oxidative membrane products (TBARS) in RBCs and liver, and plasma SAMe concentrations were evaluated. SAMe administered PO significantly increased plasma SAMe concentrations, and peak concentrations usually occurred 2-4 hours after dosing. Chronic SAMe administration did not change peak or cumulative plasma SAMe concentrations and did not [corrected] cause overt signs of toxicity. A positive influence on RBC and hepatic redox status (RBC TBARS reduced 21.1% [P < .002], liver GSH increased 35% [P < .002], liver RGSH: GSSG ratio increased 69% [P < .03]) and improved RBC resilience to osmotic challenge (P < .03) were observed. Results prove that this SAMe PO product is enterically available and suggest that it imparts biologic effects that might be useful for attenuating systemic or hepatic oxidant challenge.


Asunto(s)
Bilis/efectos de los fármacos , Gatos/metabolismo , Eritrocitos/efectos de los fármacos , Hígado/efectos de los fármacos , S-Adenosilmetionina/farmacología , Animales , Bilis/fisiología , Esquema de Medicación/veterinaria , Eritrocitos/fisiología , Femenino , Glutatión/metabolismo , Disulfuro de Glutatión/metabolismo , Hígado/fisiología , Estudios Longitudinales , Fragilidad Osmótica/efectos de los fármacos , Oxidación-Reducción , S-Adenosilmetionina/administración & dosificación , Comprimidos Recubiertos
13.
J Vet Intern Med ; 29(3): 877-81, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25858585

RESUMEN

OBJECTIVE: To determine if concentrations of free thyroxine (FT4) measured by semi-automated chemiluminescent immunoassay (CLIA) correspond to FT4 determined by equilibrium dialysis (ED) in hypothyroid dogs positive for thyroglobulin antibody (TGA). ANIMALS: Thirteen TGA-positive dogs classified as hypothyroid based on subnormal FT4 concentrations by ED. METHODS: Qualitative assessment of canine TGA was performed using an enzyme-linked immunosorbent assay. Serum total thyroxine and total triiodothyronine concentrations were measured by radioimmunoassay. Serum FT4 concentration was determined by ED, and also by semi-automated CLIA for human FT4 (FT4h) and veterinary FT4 (FT4v). Canine thyroid stimulating hormone concentration was measured by semi-automated CLIA. RESULTS: Each dog's comprehensive thyroid profile supported a diagnosis of hypothyroidism. For detection of hypothyroidism, sensitivities of CLIA for FT4h and FT4v were 62% (95% CI, 32-85%) and 75% (95% CI, 36-96%), respectively, compared to FT4 by ED. Five of 13 (38%) dogs had FT4h and 2 of 8 (25%) dogs had FT4v concentrations by CLIA that were increased or within the reference range. Percentage of false-negative test results for FT4 by CLIA compared to ED was significantly (P < .0001 for FT4h and P < .001for FT4v) higher than the hypothesized false-negative rate of 0%. CONCLUSIONS AND CLINICAL IMPORTANCE: Caution should be exercised in screening dogs for hypothyroidism using FT4 measured by CLIA alone. Some (25-38%) TGA-positive hypothyroid dogs had FT4 concentrations determined by CLIA that did not support a diagnosis of hypothyroidism.


Asunto(s)
Autoanticuerpos/inmunología , Enfermedades de los Perros/sangre , Hipotiroidismo/veterinaria , Mediciones Luminiscentes/veterinaria , Tiroglobulina/inmunología , Tiroxina/sangre , Animales , Enfermedades de los Perros/diagnóstico , Enfermedades de los Perros/inmunología , Perros , Ensayo de Inmunoadsorción Enzimática/veterinaria , Reacciones Falso Positivas , Femenino , Enfermedad de Hashimoto/sangre , Enfermedad de Hashimoto/diagnóstico , Enfermedad de Hashimoto/inmunología , Enfermedad de Hashimoto/veterinaria , Hipotiroidismo/sangre , Hipotiroidismo/diagnóstico , Hipotiroidismo/inmunología , Mediciones Luminiscentes/métodos , Masculino , Tiroiditis Autoinmune/sangre , Tiroiditis Autoinmune/diagnóstico , Tiroiditis Autoinmune/inmunología , Tiroiditis Autoinmune/veterinaria , Tirotropina/sangre , Triyodotironina/sangre
14.
J Bone Miner Res ; 13(7): 1134-40, 1998 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9661077

RESUMEN

There is a need to better understand potential bone mineral density (BMD) loss during the menopausal transition since this period may include the initiation of interventions. The study purpose was to determine if there was BMD loss at the femoral neck, lumbar spine, or total body bone sites in a population-based study of women approaching or transitioning the midlife. The 583 enrollees were 25-45 years of age at the first of four annual measurements from 1992 through 1996. Bone mineral content and bone width were measured using dual-energy X-ray absorptiometry. Considering all enrollees collectively, there was a significant 3-year decline (1%) in BMD at the femoral neck over the 3-year period (p = 0.076). There was no significant annual change in the lumbar spine (p = 0.11), and a significant annual increase in the total body BMD (p = 0.0003). Within subgroups and cross-sectionally, BMD values of the femoral neck were 5% lower in women classified as perimenopausal compared with premenopausal enrollees; BMD was 3% and 1% lower at the lumbar spine and total body site, respectively. Longitudinally, among perimenopausal women, a double oophorectomy was associated with BMD loss in the spine (p = 0.0003), even though 75-85% of these women had a hormone replacement prescription at some time during the study period. In summary, the site with evidence of loss was the femoral neck, specifically among perimenopausal women. There was little evidence of substantial total body or lumbar spine BMD loss in premenopausal women with ovaries who maintained follicle-stimulating hormone levels < 20 mIU/l in the early follicular period. Double oophorectomy, even with hormone replacement, was associated with bone loss.


Asunto(s)
Densidad Ósea/fisiología , Premenopausia/fisiología , Población Blanca , Absorciometría de Fotón , Adulto , Estudios de Cohortes , Estudios Transversales , Terapia de Reemplazo de Estrógeno , Femenino , Cuello Femoral/diagnóstico por imagen , Humanos , Vértebras Lumbares/diagnóstico por imagen , Michigan , Persona de Mediana Edad , Ovariectomía , Análisis de Regresión , Encuestas y Cuestionarios
15.
J Bone Miner Res ; 13(7): 1191-202, 1998 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9661084

RESUMEN

We hypothesized that lower ovarian and gonadotropin hormone concentrations would be associated with lower levels of peak bone mineral density (BMD) in apparently normally menstruating women who did not exercise intensively and did not report anorexia or bulimia. This hypothesis was evaluated using a case-with-control study design (n = 65) which was nested within a population-based longitudinal study of peak bone mass (Michigan Bone Health Study) with annual assessment in women aged 25-45 years (n = 582). Cases were 31 premenopausal women with BMD of the lumbar spine, femoral neck, and total body less than the 10th percentile of the distribution, where controls were 34 premenopausal women with BMD between the 50th and 75th percentile. BMD was measured by dual-energy X-ray absorptiometry. In addition to their annual measurement, these 65 participants collected first-voided morning urine specimens daily through two consecutive menstrual cycles. The urine from alternating days of this collection was analyzed for estrone-3-glucuronide (E1G), pregnanediol glucuronide (PdG), testosterone, and follicle-stimulating hormone by radioimmunoassay and these values adjusted for daily creatinine excretion levels. Additionally, analyses of daily urine specimens for luteinizing hormone (uLH) was undertaken to better characterize the possible uLH surge. Cases had significantly lower amounts of E1G (p = 0.009) and PdG (p = 0.002) than did controls, whether amounts were characterized by a mean value, the highest value, or the area under the curve, and after statistically controlling for body size. Further, when B-splines were used to fit lines to the E1G and PdG data across the menstrual cycle, the 95% confidence intervals (CIs) about the line for the controls consistently excluded and excluded and exceeded the 95% confidence bands for the cases in the time frame associated with the luteal phase in ovulatory cycles. Likewise, 95% CIs for the LH surge in controls exceeded the fitted line for cases around the time associates with the LH surge. The cases and controls were not different according to dietary intake (energy, protein, calcium), family history of osteoporosis, reproductive characteristics (parity, age at menarche, age of first pregnancy), follicular phase serum hormone levels, calciotropic hormone levels, or by evidence of perimenopause. We conclude that these healthy, menstruating women with BMD at the lowest 10th percentile from a population-based study had significantly lower urinary sex steroid hormone levels during the luteal phase of menstrual cycles as compared with hormone levels in premenopausal women with BMD between the 50th and 75th percentile of the same population-based study, even after considering the role of body size. These data suggest that subclinical decreases in circulating gonadal steroids may impair the attainment and/or maintenance of bone mass in otherwise reproductively normal women.


Asunto(s)
Densidad Ósea , Hormona Folículo Estimulante/orina , Gonadotropinas/orina , Hormona Luteinizante/orina , Premenopausia/orina , Testosterona/orina , Absorciometría de Fotón , Adulto , Estudios de Casos y Controles , Estrógenos Conjugados (USP)/orina , Estrona/análogos & derivados , Estrona/orina , Femenino , Cuello Femoral/diagnóstico por imagen , Humanos , Vértebras Lumbares/diagnóstico por imagen , Michigan , Aptitud Física/fisiología , Pregnanodiol/análogos & derivados , Pregnanodiol/orina
16.
J Clin Endocrinol Metab ; 72(6): 1278-85, 1991 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-1902845

RESUMEN

Polycystic ovarian disease (PCO) is characterized by hyperandrogenism, ovulatory dysfunction, and altered gonadotropin secretion. Mean plasma FSH concentrations are low, while LH is elevated in a majority of patients. LH pulsatile secretion has been shown to occur at rapid follicular phase frequencies (approximately one pulse per h) in PCO, suggesting persistent rapid frequency GnRH secretion in this disorder. Anovulatory women with PCO were given estradiol (E2; Estraderm skin patches) and progesterone (P; vaginal suppositories) to produce midluteal concentrations for 21 days. The aim was to determine if E2 and P would slow LH (GnRH) pulse frequency and if this would result in augmented FSH secretion and follicular development after withdrawal of E2 and P. Plasma LH was measured every 10 min for 8 h before, during (days 10 and 20), and 7 days after withdrawal of E2 and P (day 28). On each of these study days FSH was measured hourly, and E2 and P were measured every 2 h. After sampling, GnRH (25 and 250 ng/kg, iv) was given to assess pituitary responsiveness. Follicular development was monitored by vaginal ultrasound through day 34 of the study. Basal LH frequency was 8.5 +/- 0.5 pulses/8 h (mean +/- SEM). During E2 and P, LH pulse frequency fell to 3.3 +/- 1.0 (10 days) and 2.3 +/- 0.8 (20 days), 39% and 27% of the basal value, respectively, and subsequently increased to 5.6 +/- 0.7 (66% of basal) 7 days after withdrawal of E2 and P. LH pulse amplitude (basal, 7.2 +/- 1.5 IU/L) was not reduced until day 20, but remained suppressed (3.9 +/- 1.1 IU/L) on day 28. As a result, mean LH (basal, 21.0 +/- 3.5 IU/L) fell progressively during E2 and P, to 3.8 +/- 1.2 IU/L on day 20, and remained low (39% of basal) 7 days after steroid withdrawal. Mean plasma FSH (basal, 7.1 +/- 0.9 IU/L) also fell during steroid administration, but in contrast to LH, had risen to 93% of the basal value by 7 days after E2 and P. LH release in response to exogenous GnRH revealed marked initial responses which did not decrease until day 20, but remained suppressed (8% of basal) after withdrawal of E2 and P. FSH responses were also suppressed on day 20, but had increased to 75% of the basal value by day 28. Initiation of follicular development occurred in all patients, and the lead follicle measured 12.3 +/- 0.8 mm 13 days post-E2 and P. Ovulation occurred in one patient.(ABSTRACT TRUNCATED AT 400 WORDS)


Asunto(s)
Hormona Folículo Estimulante/metabolismo , Hormona Liberadora de Hormona del Crecimiento/metabolismo , Síndrome del Ovario Poliquístico/metabolismo , Adulto , Andrógenos/sangre , Estradiol/sangre , Estradiol/farmacología , Femenino , Humanos , Hormona Luteinizante/sangre , Hormona Luteinizante/metabolismo , Folículo Ovárico/efectos de los fármacos , Folículo Ovárico/crecimiento & desarrollo , Progesterona/sangre , Progesterona/farmacología , Prolactina/sangre , Flujo Pulsátil
17.
J Clin Endocrinol Metab ; 80(7): 2210-6, 1995 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-7608281

RESUMEN

We measured two bone-formation markers, osteocalcin and bone-specific alkaline phosphatase, and one bone-resorption marker, N-telopeptide, in a longitudinal study in order to describe levels of these markers in lactating and nonlactating women after parturition. This 18-month postpartum period included an initial 6 months in which a 5% short-term bone loss occurred at both spine and femoral neck among breast-feeding women. The second part of the 18-month period was characterized by bone recovery among women who had lost bone. These bone-change characteristics provided an opportunity to evaluate the performance of biochemical markers during both bone loss and recovery and to identify environmental exposures during lactation associated with bone turnover. The eligible population comprised 115 women whose bone-turnover markers were measured at 2 weeks (baseline) and at 2, 4, 6, 12, and 18 months after parturition. Participants reported reproductive characteristics, diet, physical activity, use of medications, and infant-feeding practices at each contact. Women were grouped according to lactation duration: 0-1 months, 2-5 months, and 6 months or more. Women who breast-fed for at least 6 months had significantly different levels of all three bone-turnover markers compared with the levels in bottle-feeding controls, which were indicative of substantially increased bone turnover. Factors that predicted the difference in biochemical markers from baseline to 6-month values by regression analysis were lactation of 2-6 months duration and lactation for 6 months or more. Dietary calcium intake, physical activity level, and body size did not explain the differences in the change from the baseline level to the 6-month level, a period of time that corresponded with bone loss in the lactating women. Factors that predicted the differences in bone-turnover markers between 6 and 18 months (the time of bone-mass recovery) were lactation status and number of months to resumption of menses. By the 18-month observation, there was no difference in the mean values for the measured bone-turnover markers among the three lactation groups. This suggests that menstrual activity, rather than diet or physical activity, is the primary factor in bone-mass recovery after the bone loss of lactation.


Asunto(s)
Fosfatasa Alcalina/sangre , Biomarcadores/sangre , Densidad Ósea , Desarrollo Óseo , Resorción Ósea , Lactancia Materna , Colágeno/sangre , Lactancia/fisiología , Osteocalcina/sangre , Péptidos/sangre , Periodo Posparto/fisiología , Adulto , Factores de Edad , Calcio de la Dieta , Colágeno Tipo I , Femenino , Humanos , Estudios Longitudinales , Estadísticas no Paramétricas , Factores de Tiempo
18.
Obstet Gynecol ; 69(1): 96-8, 1987 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-3796928

RESUMEN

To test the hypothesis that an abnormal luteal phase is associated with significant symptoms of premenstrual syndrome, psychologic and somatic premenstrual syndrome symptoms were evaluated in a group of 83 infertile patients undergoing timed endometrial biopsy for the assessment of luteal phase adequacy. The severity of psychologic and somatic symptoms was evaluated separately. It was found that luteal phase defect, defined by endometrial biopsy, was associated with less severe psychologic and no more severe somatic symptoms of premenstrual syndrome in comparison with normal luteal phase controls. The data suggest that the hormonal milieu associated with luteal phase defects does not correlate with premenstrual syndrome symptoms and do not support the hypothesis that suboptimal ovarian function causes premenstrual syndrome.


Asunto(s)
Infertilidad Femenina/fisiopatología , Fase Luteínica , Síndrome Premenstrual/fisiopatología , Adulto , Biopsia , Endometrio/patología , Femenino , Humanos , Síndrome Premenstrual/psicología , Trastornos Psicofisiológicos/psicología
19.
Obstet Gynecol ; 69(6): 926-8, 1987 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-3574822

RESUMEN

It has been suggested that tubal ligation may cause luteal phase defects. To assess this possibility, we performed a retrospective analysis of the incidence of luteal phase defects in 72 women who had undergone tubal sterilization. In preparation for tubal reanastomosis, late luteal phase endometrial biopsy was performed. The biopsy was dated in a blind manner and designated either normal or out of phase. This group of patients was compared with a group of 32 women seen for artificial insemination with donor sperm. Luteal phase defect was defined as two biopsies out of phase by two or more days. There were no cases of luteal phase defect in either of the two groups; luteal phase defects were found in 4% of all infertility patients seen during the time of this study. These data do not support the contention that sterilization by tubal ligation leads to an increased incidence of luteal phase defect.


Asunto(s)
Endometrio/fisiología , Fase Luteínica , Reversión de la Esterilización , Esterilización Tubaria , Adulto , Femenino , Humanos , Infertilidad Femenina/fisiopatología , Inseminación Artificial Heteróloga , Estudios Retrospectivos
20.
Fertil Steril ; 55(6): 1099-105, 1991 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-1903729

RESUMEN

OBJECTIVE: To examine the in vitro responsiveness of cultured luteinized human granulosa cells over time to insulin-like growth factor 1 (IGF-1), human follicle-stimulating hormone (FSH), and human chorionic gonadotropin (hCG) for the induction of aromatase activity. DESIGN: Granulosa cells were retrieved from preovulatory follicles in patients undergoing in vitro fertilization. Cells were cultured for a period of 72 hours or 10 days. The ability of hCG, human FSH, and/or IGF-I to induce aromatase activity was assayed by the stereospecific release of tritium from [1B-3H]androstenedione. RESULTS: Short-term cultures (72 hours) demonstrated a marked rise in aromatase activity in response to human FSH and IGF-I, whereas a smaller response to hCG was observed. In contrast, 10-day cultures demonstrated responsiveness predominantly to hCG rather than human FSH for the induction of aromatase activity with no remarkable effect of IGF-I. CONCLUSION: Luteinized human granulosa cells undergo a transformation from an initial human FSH and IGF-I responsive state to an hCG responsive state in long-term cultures.


Asunto(s)
Aromatasa/biosíntesis , Gonadotropina Coriónica/farmacología , Hormona Folículo Estimulante/farmacología , Células de la Granulosa/enzimología , Factor I del Crecimiento Similar a la Insulina/farmacología , Androstenodiona/metabolismo , Células Cultivadas , Inducción Enzimática , Femenino , Fertilización In Vitro , Células de la Granulosa/efectos de los fármacos , Humanos , Cinética , Tritio
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