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1.
Breast Cancer Res Treat ; 93(3): 277-87, 2005 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16172794

RESUMEN

A double-blind, randomised, placebo-controlled pilot study was initiated to evaluate the feasibility of chemoprevention with toremifene 60 mg/day in healthy women at high risk for breast cancer. Enrolment in the study was terminated earlier than planned because of slow patient accrual, although 13% of patients continued for 5 years. The revised efficacy outcomes were change in bone mineral density (BMD) from baseline at four skeletal sites, plus effects on serum lipids. In premenopausal women there was a trend for sustained increase in BMD during toremifene therapy after year 1 in lumbar spine. In postmenopausal women, toremifene had little or no effect on BMD trends. Levels of total and low-density lipoprotein (LDL) cholesterol were largely unchanged from baseline in premenopausal women treated with toremifene but were often slightly lower than in the placebo group during follow-up. Total and LDL cholesterol levels declined slightly from baseline in the postmenopausal women and were, at several points during the first 3 years, significantly lower than in the corresponding placebo group (p < 0.01). We conclude that: (a) assessment of toremifene 60 mg/day in chemoprevention will require further clinical trials; (b) toremifene 60 mg/day has no substantive negative effects on BMD in pre- or postmenopausal women and may exert a minor favourable influence (in particular, the effects of toremifene 60 mg/day on BMD in premenopausal women may make the drug an attractive alternative to tamoxifen 20 mg/day for that patient subset); (c) lipid effects of toremifene 60 mg/day are, at minimum, neutral and may be modestly favourable for reducing cardiovascular risk.


Asunto(s)
Densidad Ósea/efectos de los fármacos , Neoplasias de la Mama/prevención & control , Colesterol/sangre , Moduladores Selectivos de los Receptores de Estrógeno/farmacología , Toremifeno/farmacología , Triglicéridos/sangre , Adulto , Análisis de Varianza , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Femenino , Finlandia/epidemiología , Humanos , Persona de Mediana Edad , Proyectos Piloto , Posmenopausia , Premenopausia , Moduladores Selectivos de los Receptores de Estrógeno/administración & dosificación , Moduladores Selectivos de los Receptores de Estrógeno/efectos adversos , Toremifeno/administración & dosificación , Toremifeno/efectos adversos , Reino Unido/epidemiología
2.
Am J Kidney Dis ; 37(4): 699-705, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11273868

RESUMEN

The traditional workup for primary aldosteronism is cumbersome and requires discontinuing antihypertensive medications, which is inconvenient and potentially dangerous. A simple and accurate screening test that can be used without modifying medications is needed. The plasma aldosterone-renin ratio (ARR) is a valid screening assay for primary aldosteronism, but antihypertensives are usually discontinued before obtaining this ratio, limiting its utility. The present prospective study is designed to examine the validity of the ARR as a screening test for primary aldosteronism if the ratio is measured randomly while patients continue antihypertensive therapy. During the 18-month study period, 90 patients were referred to the hypertension clinic with poorly controlled hypertension. ARR was measured in random blood samples in all 90 patients while maintaining their prescribed antihypertensive medications. Those with elevated ARRs (>100 ng/dL / ng/mL/h) underwent further diagnostic workup, including adrenal computed tomography and/or magnetic resonance imaging and adrenal iodine 131 norcholesterol uptake scan. Fifteen patients (17%) had elevated ARRs greater than 100:1. Ten of 15 patients were found to have adrenal adenoma on diagnostic workup, and adenoma was later confirmed by histological examination after surgical removal in these 10 patients. Five patients were found to have adrenal hyperplasia; all 5 patients responded to antialdosterone treatment. Thus, all 15 patients had good control of blood pressure after surgery and/or antialdosterone medications. No patient showed a falsely elevated ARR. Data suggest that the ARR is a valid screening assay for primary aldosteronism in patients with poorly controlled blood pressure, and discontinuation of antihypertensive medications is not needed for this test.


Asunto(s)
Aldosterona/sangre , Antihipertensivos/uso terapéutico , Hiperaldosteronismo/diagnóstico , Hipertensión/tratamiento farmacológico , Renina/sangre , Adenoma/complicaciones , Adenoma/diagnóstico , Neoplasias de las Glándulas Suprarrenales/complicaciones , Neoplasias de las Glándulas Suprarrenales/diagnóstico , Adulto , Antihipertensivos/administración & dosificación , Femenino , Humanos , Hiperaldosteronismo/sangre , Hiperaldosteronismo/complicaciones , Hipertensión/sangre , Hipertensión/etiología , Masculino , Persona de Mediana Edad , Estudios Prospectivos
3.
J Gerontol A Biol Sci Med Sci ; 54(3): M111-6, 1999 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10191837

RESUMEN

BACKGROUND: Although the association of clinical hypothyroidism with cognitive deficits is well known, the cognitive effects of thyroid hormones in euthyroid subjects are less studied and understood. The purpose of this study was to examine thyroid-cognition relationships in healthy, euthyroid older men. METHODS: We examined healthy men (N = 44, mean age = 72), excluding clinically hypothyroid/hyperthyroid or diabetic/hyperglycemic subjects and those with dementia, depression, CNS medications, or recent illness. Plasma samples obtained across a 24-hour period were pooled, then assayed for total thyroxine (TT4), total triiodothyronine (TT3), and T3 resin uptake. Free thyroxine index (FT4I) was calculated. A broad cognitive battery (including the Wechsler Adult Intelligence Scale-Revised [WAIS-R], the Dementia Rating Scale [DRS], and the Rivermead Behavioral Profile [PROFILE]) was administered to all subjects. RESULTS: Regression analyses controlling age and education showed TT4 and FT4I to have significant positive relationships with measures of overall cognition; TT4 accounted for 8% to 12% of the variance in omnibus cognitive measures such as WAIS Performance, WAIS Verbal score, and GLOBAL cognitive scores. CONCLUSIONS: Our findings suggest that within "normal" range of variation in plasma thyroid hormones, TT4 but not T3 positively associates with general cognition in healthy elderly men.


Asunto(s)
Envejecimiento/fisiología , Cognición/fisiología , Hormonas Tiroideas/fisiología , Anciano , Trastornos del Conocimiento/etiología , Demencia/fisiopatología , Escolaridad , Humanos , Hipotiroidismo/complicaciones , Inteligencia/fisiología , Masculino , Memoria/fisiología , Tiempo de Reacción/fisiología , Análisis de Regresión , Hormonas Tiroideas/sangre , Tiroxina/sangre , Tiroxina/fisiología , Triyodotironina/sangre , Triyodotironina/fisiología , Conducta Verbal/fisiología
4.
J Immunol Methods ; 213(1): 87-97, 1998 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-9671127

RESUMEN

GAD65Ab and ICA512Ab are strongly associated with insulin-dependent (Type 1) diabetes mellitus. A novel, simple radio-antigen binding assay with microSepharose conjugated with monoclonal antibodies specific for human immunoglobulin light chains was developed to provide diagnostic sensitivity and specificity of GAD65Ab and ICA512Ab for Type 1 diabetes. The Receiver Operating Characteristic (ROC) curve was used to determine the upper level of Normal in 583 new onset Type 1 diabetic patients and in 829 matched controls. The sensitivity of GAD65Ab and ICA512Ab was 66% (384/583) and 41% (211/520), respectively, and the diagnostic specificity was 96% for both autoantibodies. Levels, but not frequency, of GAD65Ab were higher among female Type 1 diabetes patients, whereas ICA512Ab levels did not differ between males and females. Positivity for GAD65Ab. ICA512Ab or both showed a sensitivity of 74% and a specificity of 92% for Type 1 diabetes. This simple, one-step centrifugation, high-capacity radio-antigen binding assay has a high precision and reproducibility to accurately detect both GAD65Ab and ICA512Ab. This assay should also prove useful in other autoantibody assays against conformation-sensitive autoantigens.


Asunto(s)
Autoanticuerpos/sangre , Autoantígenos/inmunología , Diabetes Mellitus Tipo 1/sangre , Diabetes Mellitus Tipo 1/inmunología , Glutamato Descarboxilasa/inmunología , Proteínas de la Membrana/inmunología , Proteínas Tirosina Fosfatasas/inmunología , Adolescente , Adulto , Factores de Edad , Autoanticuerpos/inmunología , Femenino , Humanos , Masculino , Proteína Tirosina Fosfatasa no Receptora Tipo 1 , Proteínas Tirosina Fosfatasas Clase 8 Similares a Receptores , Sensibilidad y Especificidad , Sefarosa , Factores Sexuales , Proteína Estafilocócica A , Factores de Tiempo
5.
Arch Intern Med ; 158(3): 294-6, 1998 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-9472211

RESUMEN

We report a case of subtle Cushing syndrome in a Pakistani man who self-treated his asthma with a potent long-acting oral glucocorticoid (betamethasone disodium phosphate [Bentelan]) for more than 30 years. He presented with cushingoid features, insulin resistance, and refractory hypertension. Laboratory evaluation revealed undetectable cortisol levels and suppression of the hypothalamic-pituitary-adrenal axis. The patient obtained the drug from his country of origin, with no understanding of the potential adverse effects imposed by long-term use of steroids. He is now being slowly weaned off the drug. The apparent widespread availability, access, and abuse of such potent steroids are a cause of concern in developing countries. We suggest that physicians in the United States be aware of the potential abuse of such potent drugs in all populations, including immigrants.


Asunto(s)
Betametasona/análogos & derivados , Síndrome de Cushing/inducido químicamente , Automedicación/efectos adversos , Asma/tratamiento farmacológico , Betametasona/administración & dosificación , Betametasona/efectos adversos , Síndrome de Cushing/metabolismo , Humanos , Masculino , Persona de Mediana Edad
6.
Ann Epidemiol ; 6(6): 507-19, 1996 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-8978881

RESUMEN

The Women's Health Trial: Feasibility Study in Minority Populations (WHT:FSMP), a randomized trial of 2208 women, was conducted to investigate three questions. First, can women from minority and low-socioeconomic-status populations be recruited in numbers sufficient to evaluate a dietary intervention designed to lower fat intake. Second, the efficacy of a low fat, increased fruit/vegetable/ grain product intervention for reducing fat consumption. Third, will participation in the intervention lower plasma cholesterol and estradiol levels relative to the controls. The baseline results showed that an adequate number of minority and low SES women could be recruited to test the study hypotheses. A diverse study population of postmenopausal women consuming a high fat diet was recruited: 28% of participants were Black, 16% were Hispanic, 11% had less than a high school level of education, and 15.5% had household incomes of < $15,000.


Asunto(s)
Colesterol en la Dieta , Grasas de la Dieta , Grupos Minoritarios , Ensayos Clínicos Controlados Aleatorios como Asunto , Proyectos de Investigación , Salud de la Mujer , Anciano , Análisis de Varianza , Colesterol en la Dieta/efectos adversos , Grasas de la Dieta/efectos adversos , Estudios de Factibilidad , Femenino , Humanos , Persona de Mediana Edad , Cooperación del Paciente , Selección de Paciente , Reproducibilidad de los Resultados , Factores de Riesgo , Factores Socioeconómicos
7.
J Clin Pharm Ther ; 21(1): 29-35, 1996 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8737181

RESUMEN

We prospectively assessed 99 Southeast Asians for the presence of thyroid disease who were attending a primary care clinic devoted to the care of refugees. Subjects were undergoing evaluation as new patients and had no previously diagnosed thyroid abnormality. Each patient had a physical examination performed by his or her primary-care provider, was given a standardized questionnaire that focused on symptoms of thyroid disease and underwent a venipuncture for total thyroxine, triiodothyronine resin uptake and thyrotropin (TSH) concentration. Those who had an abnormal examination, calculated free thyroxine index (FT4I) or TSH level were re-examined by an endocrinologist and had repeat thyroid studies performed. Although 81% of patients reported > or = 1 symptom compatible with thyroid dysfunction, only 17% were found to have laboratory abnormalities. An abnormal FT4I and TSH level was found in 5% and 13% of subjects, respectively, but only one case of clinically significant hyperthyroidism and no cases of hypothyroidism were confirmed. TSH suppression, noted in 12% of subjects, persisted over a median follow-up of 6 months. Among seven patients with an anatomic abnormality of the thyroid, four had an abnormal FT4I or TSH. We conclude that the clinical prevalence of symptomatic thyroid dysfunction among Southeast Asians is comparable to that reported for non-Asian populations, but that the frequency of subclinical hyperthyroidism may be higher. Although symptoms suggestive of thyroid disease are common, routine screening for thyroid disease is not indicated in this study.


Asunto(s)
Refugiados , Enfermedades de la Tiroides/epidemiología , Adulto , Anciano , Anciano de 80 o más Años , Asia Sudoriental/etnología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Enfermedades de la Tiroides/etnología , Washingtón/epidemiología
8.
J Gerontol A Biol Sci Med Sci ; 50(4): M222-6, 1995 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-7614245

RESUMEN

BACKGROUND: Sleep quality declines with age, with less time in deep or slow wave sleep (SWS) and reduced amplitude of the delta waves that characterize it. Age-related declines also occur in lean body mass, growth hormone (GH), and insulin-like growth factor 1 (IGF-1). These changes in sleep quality and anabolic status may be related, as administration of GH or growth hormone releasing hormone (GHRH) can enhance SWS and decrease awakenings in young men. Here we examine the relationship between plasma IGF levels and delta sleep quality in older men. METHODS: The sleep EEG of 30 healthy elderly men (64 +/- 6 yrs; range 50-75) was recorded on the second of 2 consecutive nights. Plasma samples were drawn within 3 weeks of EEG recording, and IGF levels were assayed by RIA after acid extraction. RESULTS: IGF explained 28% (semi-partial correlation coefficient r = .53; p = .003) of the variance in average delta energy per epoch of SWS, after age-related variance was removed. Higher IGF was associated with higher average delta energy. Similar results were obtained for total delta energy during SWS (r = .37, p = .04) 4nd time spent in SWS (r = .42, p = .02). Other measures of sleep quality (e.g., wakefulness, REM sleep) were not correlated with IGF. The IGF delta relationship was minimally influenced by moderator variables such as thyroxine (T3, T4), and/or body mass index (BMI). CONCLUSION: We conclude that age-adjusted IGF levels in healthy senior men co-vary significantly with SWS and the delta energy that characterizes it.


Asunto(s)
Ritmo Delta , Factor I del Crecimiento Similar a la Insulina/metabolismo , Sueño/fisiología , Anciano , Electroencefalografía , Humanos , Masculino , Persona de Mediana Edad , Radioinmunoensayo
9.
Am J Clin Pathol ; 103(4): 386-90, 1995 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-7726131

RESUMEN

The authors have examined the utility of using the rate of change of the human chorionic gonadotropin (hCG) level and progesterone concentration to distinguish ectopic from normal intrauterine pregnancies. Patients suspicious for ectopic pregnancy had three outcomes: normal intrauterine gestation (NIUG), ectopic pregnancy (ECT), and inevitable abortion (IAB). The rate of change of the hCG level and the progesterone concentration distinguish NIUG from ECT with good sensitivity and specificity at optimal cut-offs of 0.14 (rate of change of the logarithm of hCG) and 8 ng/mL (progesterone). As the biochemical parameters of the ECT and IAB groups overlap, stating that NIUG can be biochemically distinguished from ECT is misleading. Thus, the authors have grouped them together as pathologic pregnancies (PATH). The rate of change of the hCG level and the progesterone concentration distinguish NIUG from PATH with good sensitivity and specificity with the same optimal cut-offs of 0.14 (rate of change of the logarithm of hCG) and 8 ng/mL (progesterone).


Asunto(s)
Embarazo Ectópico/diagnóstico , Aborto Espontáneo/sangre , Gonadotropina Coriónica/sangre , Femenino , Humanos , Embarazo , Resultado del Embarazo , Embarazo Ectópico/sangre , Progesterona/sangre , Valores de Referencia , Estudios Retrospectivos , Sensibilidad y Especificidad , Factores de Tiempo
10.
Clin Endocrinol (Oxf) ; 40(6): 725-31, 1994 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8033362

RESUMEN

OBJECTIVE: In men and male monkeys, a short-term fast has been reported to have a major effect on the reproductive axis. In this study we investigated the effects of a short-term fast (72 hours) on female reproductive hormone secretion and menstrual function. DESIGN: The study consisted of an admission day (control), three successive fasting days (fast 1, 2 and 3) and a refeeding day (post fast). PATIENTS: Eight normal cycling women, ages 21-35, within 10% of ideal body weight, were fasted for 72 hours during the follicular phase of their menstrual cycle. MEASUREMENTS: On the admission day, the last day of the fast and the day of refeeding, blood samples were collected at 10-minute intervals from 0800 to 2000 h for determination of the LH pulse pattern. Daily determinations of immuno LH, FSH, oestradiol (E) and progesterone (P) were performed throughout the menstrual cycle in which the fast occurred. RESULTS: Throughout the fasting days, the consistently low serum levels of glucose and insulin confirmed that all the subjects were fasting. However, in spite of profound metabolic changes and a significant loss of weight, the short-term fast did not have discernible effects upon the reproductive hormones studied. Basal mean LH concentrations did not show any significant variation throughout the study period. The mean +/- SEM number of LH pulses was 13.4 +/- 1.5/12 h on the control day, 12.4 +/- 1.2/12 h (NS) on the third day of fasting and 11.0 +/- 1.5/12 h (NS) the day of refeeding. Each woman maintained a physiological pattern of LH, FSH, E and P throughout the menstrual cycle including the LH surge; ultrasound evidence of normal growth of a dominant follicle; and cycle length consistent with previous cycles. CONCLUSIONS: Our results indicate that in spite of profound metabolic changes, a 72-hour fast during the follicular phase does not affect the menstrual cycle of normal cycling women. It appears that the female reproductive axis during this phase of the cycle is more resistant to an acute caloric deprivation than that of men or male monkeys.


Asunto(s)
Ayuno/fisiología , Gonadotropinas Hipofisarias/metabolismo , Ciclo Menstrual/fisiología , Adulto , Peso Corporal/fisiología , Estradiol/sangre , Femenino , Hormona Folículo Estimulante/sangre , Humanos , Hormona Luteinizante/sangre , Hormona Luteinizante/metabolismo , Ovario/diagnóstico por imagen , Progesterona/sangre , Tasa de Secreción/fisiología , Factores de Tiempo , Ultrasonografía
11.
Diabetologia ; 37(4): 344-50, 1994 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8063033

RESUMEN

Insulin-dependent diabetes mellitus (IDDM) is associated with autoreactivity against GAD but the diagnostic sensitivity (positivity in disease) and specificity (negativity in health) of isoform-specific GAD antibodies have yet to be defined in assay systems suitable for screening large number of samples. One set of IDDM patient (n = 10) and control (n = 50) standard sera were used to develop quantitative antibody assays with in vitro synthesized recombinant 35S-methionine-labelled GAD65 and GAD67, respectively, and protein A-Sepharose to separate free from antibody-bound ligand. Binding levels were not normally distributed (p < 0.0001) and therefore, the diagnostic accuracy of GAD antibodies was analysed by the ROC plots in population-based, consecutively-diagnosed, recent onset, 0-14 year-old patients (n = 105), and matched, healthy control subjects (n = 157). The ROC plots showed that the diagnostic sensitivity of GAD65 antibodies was 77% and the specificity 92% compared with 8% and 98%, respectively for GAD67 antibodies. In the IDDM sera, GAD65 and GAD67 antibodies were concordant in 7% (6 of 81) and GAD65 antibodies and ICA in 89% (72 of 81) without a correlation between the autoantibody levels. Autoantibodies to recombinant human islet GAD65 are specific and sensitive markers for childhood IDDM in this immunoassay with in vitro synthesized 35S-methionine-labelled recombinant GAD.


Asunto(s)
Autoanticuerpos/análisis , Diabetes Mellitus Tipo 1/diagnóstico , Glutamato Descarboxilasa/inmunología , Isoenzimas/inmunología , Adolescente , Adulto , Autoinmunidad , Niño , Diabetes Mellitus Tipo 1/inmunología , Reacciones Falso Positivas , Femenino , Humanos , Islotes Pancreáticos/inmunología , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Ensayo de Unión Radioligante , Proteínas Recombinantes/inmunología , Sensibilidad y Especificidad
12.
J Autoimmun ; 4(5): 717-32, 1991 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-1797022

RESUMEN

Daily injections of high dose human recombinant interleukin-1 beta (IL-1 beta) accelerated the onset of both insulin-dependent diabetes mellitus and lymphocytic thyroiditis in genetically prone BB rats. In diabetes-resistant BB rats, high dose IL-1 beta failed to induce diabetes. Additionally, the presence of neutralizing IL-1 beta antibodies in these rats strongly correlated with inhibition of lymphocytic thyroiditis. Since low dose IL-1 beta protects diabetes-prone rats from IDDM, we conclude that IL-1 beta is a potent modulator of autoimmune diabetes and thyroid disease in genetically susceptible rats.


Asunto(s)
Autoinmunidad , Interleucina-1/farmacología , Islotes Pancreáticos/inmunología , Glándula Tiroides/inmunología , Glándulas Suprarrenales/anatomía & histología , Factores de Edad , Animales , Diabetes Mellitus Tipo 1/inducido químicamente , Diabetes Mellitus Tipo 1/inmunología , Relación Dosis-Respuesta a Droga , Ensayo de Inmunoadsorción Enzimática , Vida Libre de Gérmenes , Inyecciones Intraperitoneales , Riñón/anatomía & histología , Masculino , Tamaño de los Órganos/efectos de los fármacos , Páncreas/anatomía & histología , Ratas , Ratas Endogámicas BB , Proteínas Recombinantes/inmunología , Bazo/anatomía & histología , Timo/anatomía & histología , Glándula Tiroides/anatomía & histología , Tiroiditis Autoinmune/inducido químicamente , Tiroiditis Autoinmune/inmunología , Tiroxina/sangre
13.
J Immunol ; 146(9): 2983-9, 1991 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-1826702

RESUMEN

To assess the role of IL-1 in the development of experimental autoimmune encephalomyelitis (EAE), the effects of in vivo treatment with IL-1 alpha or an IL-1 antagonist on the clinical course of EAE were evaluated. First, Lewis rats were immunized with guinea pig myelin in CFA and treated for 19 consecutive days with i.p. injections of recombinant human IL-1 alpha. Clinical signs of paralysis in the IL-1 alpha-treated groups were of longer duration and of greater severity compared to placebo injected controls. In addition, more weight loss was observed in the IL-1 alpha-treated groups compared to controls. This enhanced weight loss was not due to IL-1 alpha injections alone as CFA-treated rats injected with IL-1 alpha did not lose weight when compared to placebo injected, CFA-treated controls. Second, soluble mouse rIL-1R (sIL-1R), which binds both IL-1 alpha and IL-1 beta, was given as an IL-1 antagonist. Treatment of guinea pig myelin/CFA immunized rats with sIL-1R for 13 consecutive days significantly delayed the onset of EAE, reduced the severity of paralysis and weight loss, and shortened the duration of disease. Treatment with sIL-1R was most effective in reducing EAE if administered for 15 consecutive days immediately after immunization. Shortened 5-day treatment regimens spanning days 1 to 5, days 6 to 10, or days 11 to 15 after immunization were less effective in reducing EAE. These data suggest that IL-1 may initiate or promote inflammation within the central nervous system. In addition, specifically blocking the biological activity of IL-1 in vivo by soluble receptors may prove beneficial for the treatment of autoimmune or inflammatory diseases.


Asunto(s)
Enfermedades Autoinmunes/inmunología , Encefalomielitis Autoinmune Experimental/inmunología , Interleucina-1/farmacología , Receptores Inmunológicos/fisiología , Animales , Femenino , Ratas , Ratas Endogámicas Lew , Receptores Inmunológicos/química , Receptores de Interleucina-1 , Solubilidad , Factores de Tiempo
14.
J Biol Chem ; 265(16): 9413-7, 1990 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-2160978

RESUMEN

The murine lymphoid cell line 70Z/3 has been extensively used to study the intracellular mechanisms of interleukin-1 (IL-1) action. In these cells IL-1 is known to induce kappa gene expression but the signal transduction pathway has yet to be defined. IL-1-induced kappa expression is associated with stimulation of Na+/H+ exchange and activation of protein kinase C, but these events are not sufficient to trigger kappa expression. Thus, other signals must be present. Because cAMP is a well recognized second messenger, we sought to determine whether cAMP is the signal that triggers IL-1-induced kappa expression. To that end we first measured intracellular levels of cAMP following IL-1 treatment. The results showed that exposure of 70Z/3 cells to IL-1 alpha induced a rapid and a transient increase in cAMP, it peaked at 5 min and was back to base-line level at 20 min. Prostaglandin E2 (PGE2) also increased cAMP with similar kinetics to IL-1 alpha but the increased levels were far greater. IL-1 alpha-induced increase in cAMP proved not be a sufficient signal because an increase in intracellular cAMP by N6,O2'-dibutyryl cAMP (Bt2cAMP) or PGE2 failed to increase surface IgM or to increase kappa mRNA level. Although when used alone they had no effect, Bt2cAMP and PGE2 were found to amplify the IL-1 alpha-induced kappa expression. IL-1 alpha transiently activated NF-kappa B transcription factor. But this effect could not be simulated by Bt2cAMP or PGE2. This observation provides further evidence that cAMP is not a trigger of kappa expression. Although Bt2cAMP or PGE2 when used alone had no effect, they did consistently modify the level of NF-kappa B activity induced by IL-1 alpha. Results of this study show that cAMP is not sufficient to induce NF-kappa B or kappa expression. Therefore, the role of cAMP may not be trigger but rather to modulate the IL-1 alpha-induced kappa expression. Regulation of the response could occur at one or a number of points along the signal pathway. Such a regulatory role is supported by the observation that cAMP modulates the IL-1 alpha-induced NF-kappa B activity.


Asunto(s)
Linfocitos B/metabolismo , AMP Cíclico/fisiología , Expresión Génica , Cadenas kappa de Inmunoglobulina/genética , Interleucina-1/farmacología , Animales , Linfocitos B/efectos de los fármacos , Secuencia de Bases , Bucladesina/farmacología , Línea Celular , Proteínas de Unión al ADN/genética , Dinoprostona/farmacología , Cinética , Ratones , Datos de Secuencia Molecular , FN-kappa B , ARN Mensajero/metabolismo , Transducción de Señal , Factores de Transcripción/genética
15.
J Immunol ; 144(10): 3784-8, 1990 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-2332631

RESUMEN

Long term effects of in vivo treatment with human rIL-1 beta on diabetogenesis and thyroid disease were determined in the Biobreeding rat. Administration of high dose (10 micrograms/kg) IL-1 beta accelerated the onset of insulin-dependent diabetes mellitus compared to saline-injected controls. High dose treatment resulted in goiter development, pronounced LT, reduced serum T4 levels, and overall growth reduction. In contrast, low dose IL-1 beta (0.5 microgram/kg) administration significantly reduced the frequency of insulin-dependent diabetes mellitus (48%) compared to placebo (86%) and high dose IL-1 beta (93%) treatment groups. Rats protected by low dose IL-1 beta had unaffected growth rates and minimal to no pancreatic and thyroid pathology. Our results demonstrate that exogenous administration of IL-1 beta modulates Biobreeding rat idiopathic autoimmune diabetes and thyroid disease in a dose-dependent manner.


Asunto(s)
Diabetes Mellitus Tipo 1/inmunología , Interleucina-1/fisiología , Tiroiditis Autoinmune/fisiopatología , Animales , Peso Corporal , Diabetes Mellitus Tipo 1/patología , Relación Dosis-Respuesta a Droga , Interleucina-1/farmacología , Recuento de Leucocitos/efectos de los fármacos , Tamaño de los Órganos , Ratas , Ratas Mutantes/inmunología , Proteínas Recombinantes
16.
Clin Chem ; 36(2): 334-7, 1990 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-2406042

RESUMEN

We evaluated an immunochemiluminometric assay for total triiodothyronine (T3) in serum. Acridinium ester is used as chemiluminescent label, with magnetic particle separation. Intra-run precision was demonstrated by CVs of 8.6%, 8.1%, and 4.4% at T3 concentrations of 1.3, 2.2, and 4.3 nmol/L, respectively. Between-run CVs were 19.1%, 8.8%, and 6.9% at respective T3 concentrations of 0.9, 2.4, and 6.2 nmol/L. We tested the validity of a two-point calibration system by comparing it with a set of 10 calibrators; use of the latter only minimally improved assay precision. The central 95% reference range, determined by data from 109 healthy blood donors, was 1.5-3.2 nmol/L. Comparison with a standard radioimmunoassay method revealed constant error, attributed to bias or matrix effects between the different calibrators used in the two assay systems. Assay time for 60 samples was 2.5 h. We conclude that this assay is rapid and precise, and offers safety and time advantages over conventional RIA techniques.


Asunto(s)
Mediciones Luminiscentes , Triyodotironina/sangre , Adulto , Anciano , Femenino , Técnica del Anticuerpo Fluorescente , Colorantes Fluorescentes , Humanos , Masculino , Persona de Mediana Edad , Radioinmunoensayo , Juego de Reactivos para Diagnóstico , Valores de Referencia , Reproducibilidad de los Resultados
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