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3.
Schizophr Res ; 49(3): 243-51, 2001 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-11356585

RESUMEN

Evidence that the metabolism of phospholipids and polyunsaturated fatty acids (PUFA) is abnormal in schizophrenia provided the rationale for intervention studies using PUFA supplementation. An initial open label study indicating efficacy for n-3 PUFA in schizophrenia led to two small double-blind pilot studies. The first study was designed to distinguish between the possible effects of two different n-3 PUFA: eicosapentaenoic acid (EPA) and docohexaenoic acid (DHA). Forty-five schizophrenic patients on stable antipsychotic medication who were still symptomatic were treated with either EPA, DHA or placebo for 3 months. Improvement on EPA measured by the Positive and Negative Syndrome Scale (PANSS) was statistically superior to both DHA and placebo using changes in percentage scores on the total PANSS. EPA was significantly superior to DHA for positive symptoms using ANOVA for repeated measures. In the second placebo-controlled study, EPA was used as a sole treatment, though the use of antipsychotic drugs was still permitted if this was clinically imperative. By the end of the study, all 12 patients on placebo, but only eight out of 14 patients on EPA, were taking antipsychotic drugs. Despite this, patients taking EPA had significantly lower scores on the PANSS rating scale by the end of the study. It is concluded that EPA may represent a new treatment approach to schizophrenia, and this requires investigation by large-scale placebo-controlled trials.


Asunto(s)
Antipsicóticos/uso terapéutico , Ácidos Araquidónicos/uso terapéutico , Esquizofrenia/tratamiento farmacológico , Adulto , Antipsicóticos/administración & dosificación , Ácidos Araquidónicos/administración & dosificación , Ácidos Docosahexaenoicos/administración & dosificación , Ácidos Docosahexaenoicos/uso terapéutico , Método Doble Ciego , Humanos , Proyectos Piloto , Psicología del Esquizofrénico
8.
J Epidemiol Community Health ; 50(5): 481-96, 1996 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-8944853

RESUMEN

STUDY OBJECTIVE: To ascertain, from the published reports to date, whether or not a significantly increased risk of breast cancer is specifically attributable to a history of induced abortion, independent of spontaneous abortion and age at first full term pregnancy (or first live birth); to establish the relative magnitude of such risk increase as may be found, and to ascertain and quantify such risk increases as may pertain to particular subpopulations of women exposed to induced abortion; in particular, nulliparous women and parous women exposed before compared with after the first full term pregnancy. INCLUDED STUDIES: The meta-analysis includes all 28 published reports which include specific data on induced abortion and breast cancer incidence. Since some study data are presented in more than one report, the 28 reports were determined to constitute 23 independent studies. Overall induced abortion odds ratios and odds ratios for the different subpopulations were calculated using an average weighted according to the inverse of the variance. An overall unweighted average was also computed for comparison. No quality criteria were imposed, but a narrative review of all included studies is presented for the reader's use in assessing the quality of individual studies. EXCLUDED STUDIES: All 33 published reports including data on abortion and breast cancer incidence but either pertaining only to spontaneous abortion or to abortion without specification as to whether it was induced or spontaneous. These studies are listed for the reader's information. RESULTS: The overall odds ratio (for any induced abortion exposure; n = 21 studies) was 1.3 (95% confidence interval of 1.2, 1.4). For comparison, the unweighted overall odds ratio was 1.4 (1.3,1.6). The odds ratio for nulliparous women was 1.3 (1.0,1.6), that for abortion before the first term pregnancy in parous women was 1.5 (1.2,1.8), and that for abortion after the first term pregnancy was 1.3 (1.1,1.5). CONCLUSIONS: The results support the inclusion of induced abortion among significant independent risk factors for breast cancer, regardless of parity or timing of abortion relative to the first term pregnancy. Although the increase in risk was relatively low, the high incidence of both breast cancer and induced abortion suggest a substantial impact of thousands of excess cases per year currently, and a potentially much greater impact in the next century, as the first cohort of women exposed to legal induced abortion continues to age.


Asunto(s)
Aborto Inducido/efectos adversos , Neoplasias de la Mama/etiología , Aborto Espontáneo/complicaciones , Adulto , Factores de Edad , Femenino , Humanos , Edad Materna , Persona de Mediana Edad , Paridad , Embarazo , Factores de Riesgo , Estadística como Asunto
9.
Steroids ; 61(7): 429-32, 1996 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-8837296

RESUMEN

A method is described for the differential extraction of unconjugated androgens (testosterone and dihydrotestosterone) and glucuronidated androgens (androstane-3 alpha,17 beta-diol glucuronide and androsterone glucuronide) from human serum using solid-phase, gravity-flow extraction columns. In this method, 100-microL aliquots of serum are loaded onto the normal-phase columns, unconjugated androgens are eluted with ethyl ether, and glucuronides are eluted with ethyl ether containing 2% acetic acid. Glucuronide eluates are washed with 1% aqueous acetic acid to remove cross-reacting steroid sulfates. Assays of sera for the four steroids were performed using standard radioimmunoassay methodology, except for androsterone glucuronide. This steroid was assayed with a novel radioimmunoassay method that employees a tritiated, unconjugated androsterone tracer and an anti-dehydroepiandrosterone sulfate antiserum. The new method is well suited for the assay of conjugated and unconjugated steroids in large numbers of specimens, particularly where the sample volume is limited.


Asunto(s)
Andrógenos/sangre , Radioinmunoensayo/métodos , Adulto , Anciano , Andrógenos/química , Androstano-3,17-diol/análogos & derivados , Androstano-3,17-diol/sangre , Androstano-3,17-diol/química , Androsterona/análogos & derivados , Androsterona/sangre , Androsterona/química , Dihidrotestosterona/sangre , Dihidrotestosterona/química , Humanos , Concentración de Iones de Hidrógeno , Masculino , Valores de Referencia , Testosterona/sangre , Testosterona/química , Tritio
11.
Steroids ; 57(10): 485-7, 1992 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-1333653

RESUMEN

Human breast cyst fluid (BCF) contains an esterase that on the basis of electrophoretic mobility and response to inhibitors differs from those found in the plasma. From a total of 384 BCF samples analyzed for esterase using p-nitrophenyl hexanoate as substrate, 149 (39%) showed significant activity. The samples had been analyzed for the concentrations of the sulfates of estrone, estriol, dehydroepiandrosterone, as well as the potassium and sodium cations (K+/Na+). The data were submitted to statistical analysis using the Spearman rank order test. The esterase-positive samples exhibited a significant positive association with each of the steroid sulfates and the K+/Na+ ratios. Except for protein concentration, there was no significant correlation between the esterase-positive and esterase-negative cysts. These observations may have physiological significance in that high K+/Na+ ratio cysts have been related to the histological status of the cyst.


Asunto(s)
Líquidos Corporales/enzimología , Esterasas/análisis , Enfermedad Fibroquística de la Mama/enzimología , Esteroides/análisis , Sulfatos/análisis , Biomarcadores/análisis , Líquidos Corporales/química , Deshidroepiandrosterona/análogos & derivados , Deshidroepiandrosterona/análisis , Sulfato de Deshidroepiandrosterona , Estriol/análogos & derivados , Estriol/análisis , Estrógenos Conjugados (USP)/análisis , Estrona/análogos & derivados , Estrona/análisis , Femenino , Enfermedad Fibroquística de la Mama/química , Humanos , Potasio/análisis , Sodio/análisis
12.
J Clin Endocrinol Metab ; 75(4): 1002-4, 1992 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-1400863

RESUMEN

Dehydroepiandrosterone sulfate (DS) was measured by direct tritium RIA in longitudinal plasma specimens from 97 normal healthy male participants in the Baltimore Longitudinal Study of Aging. Fasting blood was collected at regular visits (approximately 1.5 yr apart) over an average 13 yr of adulthood (cumulative age range: 32-83 yr). DS was measured in 3-4 widely spaced specimens from each subject. A decline in DS was found in 65 (67%) subjects, 13 subjects (13%) showed no change, and increases were found in the 19 remaining subjects during the study period. A plot of individual data points revealed the same pattern we had obtained previously from a cross-sectional study of a different normal male population. A plot of DS values vs. age among subjects whose DS increased during the study also revealed an age-related decline. Thus, the longitudinal decrease in circulating DS, long inferred from cross-sectional data, is confirmed for normal men in the present study. A more detailed study of every specimen collected during the study period from 12 of the Baltimore Longitudinal Study of Aging subjects (4 whose values tended to be low, 4 whose values tended to be high, and 4 whose values were near the mean) failed to reveal any patterns of variation that could be correlated with changes in life circumstances, health status, or any other discernible factors. Hence, the wide variability seen in DS among individuals within normal populations remains unexplained.


Asunto(s)
Envejecimiento/sangre , Deshidroepiandrosterona/análogos & derivados , Adulto , Anciano , Anciano de 80 o más Años , Deshidroepiandrosterona/sangre , Sulfato de Deshidroepiandrosterona , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Valores de Referencia
13.
J Clin Endocrinol Metab ; 75(3): 726-9, 1992 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-1387652

RESUMEN

Estriol-3-sulfate (E3S) is present in human breast cyst fluid (BCF) in median levels of 8.7-10.4 nmol/L, yet is barely detectable in the serum (less than 0.034 nmol/L). The source of this huge concentration of E3S is unknown. It may accumulate from blood by active transport or be synthesized and concentrated within the cyst. Since estrone sulfate (E1S) and its possible precursor, dehydroepiandrosterone sulfate (DHEAS) are elevated in BCF, E3S may originate via 16 alpha-hydroxylation of E1S. The present study examined the correlations between the levels of DHEAS and E1S with those of E3S in BCF. The sodium and potassium ions were also quantified and related to the steroid concentrations. By linear regression analysis of log-normalized data there was a highly significant correlation between the concentrations of E1S and E3S (n = 355, r = 0.690, P less than 0.001) and between DHEAS and E3S (n = 361, r = 0.577, P less than 0.001). The BCF were classified according to their K/Na ion ratios: type 1, greater than 1.0, type II, less than 0.25, and type III, 0.25-1.0. By Student's t test, the concentrations of E3S differed between each BCF Type (P less than 0.002). This was also true for E1S and DHEAS. Type 1 cysts were associated with the highest estrogen sulfate levels and type II with the lowest levels. The possible physiological importance of this observation resides in reports that the BCF type expressing the highest steroid concentrations has been related to an aporcine-like epithelial lining of the cyst wall and a somewhat higher risk for developing breast cancer. The results suggest that E3S in BCF may originate from E1S, but alternate mechanisms are not precluded.


Asunto(s)
Hidrocarburo de Aril Hidroxilasas , Líquidos Corporales/metabolismo , Enfermedades de la Mama/metabolismo , Quistes/metabolismo , Estriol/análogos & derivados , Estrona/análogos & derivados , Citocromo P-450 CYP2C8 , Citocromo P-450 CYP2C9 , Deshidroepiandrosterona/análogos & derivados , Deshidroepiandrosterona/metabolismo , Sulfato de Deshidroepiandrosterona , Estriol/metabolismo , Estrona/metabolismo , Humanos , Concentración Osmolar , Potasio/metabolismo , Análisis de Regresión , Sodio/metabolismo , Esteroide 16-alfa-Hidroxilasa
14.
J Behav Med ; 15(4): 327-41, 1992 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-1404349

RESUMEN

Serum dehydroepiandrosterone sulfate (DHEA-S) levels were measured in 270 men and 153 women who were experienced practitioners of the Transcendental Meditation (TM) and TM-Sidhi programs, mental techniques practiced twice daily, sitting quietly with the eyes closed. These were compared according to sex and 5-year age grouping to 799 male and 453 female nonmeditators. The mean DHEA-S levels in the TM group were higher in all 11 of the age groups measured in women and in 6 of 7 5-year age groups over 40 in men. There were no systematic differences in younger men. Simple regression using TM-group data revealed that this effect was independent of diet, body mass index, and exercise. The mean TM-group levels measured in all women and in the older men were generally comparable to those of nonmeditator groups 5 to 10 years younger. These findings suggest that some characteristics of TM practitioners are modifying the age-related deterioration in DHEA-S secretion by the adrenal cortex.


Asunto(s)
Nivel de Alerta/fisiología , Deshidroepiandrosterona/análogos & derivados , Terapia por Relajación , Adulto , Anciano , Anciano de 80 o más Años , Estudios Transversales , Deshidroepiandrosterona/sangre , Sulfato de Deshidroepiandrosterona , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores Sexuales
15.
Steroids ; 56(6): 320-4, 1991 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-1926228

RESUMEN

A commercially available antidihydrotestosterone antiserum was used for the direct radioimmunoassay of androstenediol-3-sulfate (ADS) in human serum. Aliquots of 1 or 2 microliter male serum (mean age of 40 subjects, 38.2 +/- 5.0 years) were diluted and extracted with ethanol for assay. The tracer, [7-3H]ADS, was prepared by sodium borohydride reduction of [7-3H]dehydroepiandrosterone sulfate (DS). Significantly cross-reacting steroids were testosterone, DS, androsterone sulfate, and epiandrosterone sulfate, which combined to produce a mean overestimation of ADS of 4.3 micrograms/dl in male serum. Mean serum ADS was 23.6 +/- 10.0 micrograms/dl (SD) in 20 fresh-frozen sera versus 28.4 +/- 9.7 micrograms/dl (SD) in 20 long-term (24.4 +/- 1.2 years) frozen specimens, showing stability on long-term frozen storage. Androstenediol-3-sulfate also showed a strong correlation with serum DS (r = 0.75). The possible physiologic significance of ADS is discussed, particularly in terms of the known estrogenicity of unconjugated androstenediol.


Asunto(s)
Androstenodiol/análogos & derivados , Radioinmunoensayo/métodos , Adulto , Androstenodiol/sangre , Especificidad de Anticuerpos , Estabilidad de Medicamentos , Reacciones Falso Positivas , Congelación , Humanos , Sueros Inmunes/inmunología , Masculino , Control de Calidad , Valores de Referencia
16.
Int J Obes ; 14(6): 483-6, 1990 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-2401584

RESUMEN

The 24 h mean plasma concentrations of estrone sulfate (ES) were measured in 27 healthy obese and nonobese men (BMI: 21.2-89.5). Plasma levels of ES were found to be elevated in obese men, with ES values significantly correlated to the level of obesity (r = 0.60; P less than 0.001). Thus, an increase in plasma ES concentration (from 524 to 1115 pg/ml), compared to the less than 40 percent increases previously found for estrone and estradiol. Because ES is normally present at an approximately tenfold greater concentration than either estrone or estradiol in men, it may serve as a more easily measurable indicator of adipose tissue aromatization of androstenedione.


Asunto(s)
Estrógenos/sangre , Estrona/análogos & derivados , Obesidad/sangre , Tejido Adiposo/metabolismo , Adulto , Androstenodiona/metabolismo , Estrona/sangre , Humanos , Masculino , Persona de Mediana Edad
17.
Steroids ; 55(1): 32-5, 1990 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-2137944

RESUMEN

Duplicate aliquots of 20 fresh-frozen normal human male sera were prepared for estrone sulfate (ES) radioimmunoassay (RIA) by each of three different methods: the thin-layer chromatography (TLC) procedure we previously reported, a new procedure including overnight heating (100 C) of an ethanol extract reconstituted in dilute acetate buffer, and the new procedure with the hot incubation omitted. The purpose of the 100 C incubation was the selective thermal solvolysis of dehydroepiandrosterone sulfate (DS), the only steroid conjugate present in serum in high enough concentrations to interfere with a high-specificity ES RIA. Dehydroepiandrosterone released by solvolysis and endogenous unconjugated steroids were extracted from the samples with ether before RIA. Estrone sulfate values obtained after the thermal solvolysis preparation averaged 854 +/- 501 pg/ml (SD) versus 826 +/- 474 pg/ml (SD) after the TLC method, with excellent correlation between the two (r = 0.97). Samples prepared by the new method but with thermal solvolysis omitted averaged a 33.8% elevation of measured ES level, an elevation significantly correlated (P less than 0.02) with DS levels obtained from the same specimens. In addition, a single specimen showed no elevation after preparation by the thermal solvolysis method when up to 8 micrograms/ml authentic DS as added before extraction. Compared with the TLC method, the new method also provides substantial savings in specimen volume requirements and sample processing time.


Asunto(s)
Deshidroepiandrosterona/análogos & derivados , Estrona/análogos & derivados , Adulto , Deshidroepiandrosterona/sangre , Sulfato de Deshidroepiandrosterona , Estrona/sangre , Humanos , Masculino , Persona de Mediana Edad , Radioinmunoensayo , Valores de Referencia , Solventes
18.
Steroids ; 54(1): 21-35, 1989 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-2530662

RESUMEN

Fifty fresh-frozen normal male sera containing tritiated estrone sulfate (ES) and dehydroepiandrosterone sulfate (DS) were extracted with ethanol after ether extraction of unconjugated steroids. Washed extracts were defatted and chromatographed on polyamide-coated plates by reversed phase paired ion TLC. Plates were scanned for radioactivity, and ES peaks were cut, eluted and assayed by direct RIA with a commercially available antiserum. Mean ES values were 445 +/- 209 pg/mL (SD), in agreement with the three lowest of the seven laboratories which had previously reported normal male ES values. No differences were observed in ES values when samples were rechromatographed prior to assay, or when up to 4 micrograms/mL unlabeled DS was added to serum before extraction. These data confirm the absence of interference by DS in the current study and suggest that previously reported high (716-1194 pg/mL) mean normal male ES values reflect DS interference. The present study also demonstrates the the stability of ES in sera stored frozen at -40 C for an average of 17 years (mean: 406 +/- 258 pg/mL; [SD]; n = 41).


Asunto(s)
Deshidroepiandrosterona/análogos & derivados , Estrona/análogos & derivados , Adulto , Cromatografía en Capa Delgada/métodos , Sulfato de Deshidroepiandrosterona , Estrona/sangre , Estrona/aislamiento & purificación , Etanol , Éteres , Congelación , Humanos , Masculino , Preservación Biológica , Radioinmunoensayo
19.
Steroids ; 52(5-6): 561-70, 1988.
Artículo en Inglés | MEDLINE | ID: mdl-2978281

RESUMEN

The sulfoconjugated steroids estrone sulfate (ES) and dehydroepiandrosterone sulfate (DS) were separated in the reversed phase mode on polyamide-coated TLC plates. Baseline resolution was obtained between tritiated ES and DS standards when run with a mobile phase of 20% acetonitrile in 5mM aqueous triethylamine, triethanolamine, tris-hydroxymethylaminomethane, tributylamine or ammonia. ES and DS showed no mobility in the absence of an ion-pair reagent. The radioactive peaks were detected and integrated non-destructively by scanning. Quantitation was confirmed by elution of cut-out peak areas and liquid scintillation counting. Similar results were obtained with washed ethanol extracts of serum labeled with tritiated ES and DS. The extracts were defatted on the plate with hexane: ethyl acetate (1:1) prior to the reversed phase development.


Asunto(s)
Deshidroepiandrosterona/análogos & derivados , Estrona/análogos & derivados , Cromatografía Líquida de Alta Presión/métodos , Cromatografía en Capa Delgada/métodos , Deshidroepiandrosterona/aislamiento & purificación , Sulfato de Deshidroepiandrosterona , Estrona/aislamiento & purificación
20.
Am J Epidemiol ; 123(5): 781-9, 1986 May.
Artículo en Inglés | MEDLINE | ID: mdl-3962962

RESUMEN

Retinol and retinol-binding protein levels were measured in sera previously obtained, and stored in the frozen state, at multiphasic health checkups from 151 persons subsequently found to have lung cancer (cases) and 302 persons who remained free of cancer (controls). Two controls were matched to each case for sex, skin color, age, date of multiphasic health checkup, and aspects of the smoking habit. Mean levels in cases and controls were, respectively, retinol: 82.17 and 82.37 micrograms/dl (p = 0.93), and retinol-binding protein: 6.04 and 6.00 mg/dl (p = 0.81). Mean differences between cases and controls were, retinol: 0.195 micrograms/dl with 95% confidence limits, -3.91 and 4.30 micrograms/dl; retinol-binding protein: -0.033 mg/dl with 95% confidence limits, -0.31 and 0.24 mg/dl. No significant trend in relative risk of lung cancer was observed when the retinol or retinol-binding protein distribution was divided into quintiles. No significant associations were observed in subgroups based on age, sex, histologic type of cancer, cigarette consumption, or interval between blood drawing and cancer diagnosis. In this large study, retinol and retinol-binding protein levels were not useful in predicting the subsequent development of lung cancer.


Asunto(s)
Neoplasias Pulmonares/sangre , Proteínas de Unión al Retinol/sangre , Vitamina A/sangre , Adulto , Factores de Edad , Anciano , Métodos Epidemiológicos , Femenino , Humanos , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana Edad , Radioinmunoensayo , Riesgo , Factores Sexuales , Fumar , Factores de Tiempo , Vitamina A/metabolismo
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