RESUMEN
BACKGROUND: Hypothalamic-pituitary-adrenal axis (HPAA) suppression is the most common and dangerous, although often unrecognized and untreated, side effect of glucocorticoid administration. The risk and duration depend both on patient and treatment characteristics. High-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) currently represents the gold standard method to evaluate the metabolism of endogenous and exogenous steroids. OBJECTIVE: To assess prevalence, severity, and duration of HPAA suppression subsequent to the injection of two steroids with equivalent potency but different pharmacokinetics. SUBJECTS AND METHODS: Single-blind randomized case-control pilot study. Forty patients (22 F; age 48.7 ± 7.2 years) with shoulder calcific tendinopathy received an intrabursal injection of 40 mg of 6α-methylprednisolone acetate (MA) or triamcinolone acetonide (TA). Just before (T0) and after 1 (T1), 7 (T2), 15 (T3), 30 (T4) and 45 (T5) days, we assessed morning blood cortisol and ACTH by RIA, and 24-h urinary levels of MA, TA and free cortisol by HPLC-MS/MS. RESULTS: HPAA function was normal at baseline. At T1, all patients presented HPAA suppression reaching the lowest cortisol, ACTH and UFC levels, that were similar between groups. At T2, mean cortisol remained lower than at baseline (p < 0.0001) in the TA group. In both groups, mean cortisol and ACTH levels progressively normalized, suggesting HPA recovery, except for three patients in the MA and two in the TA group. UFC levels remained lower than normal (p < 0.0001) up to T5, despite the disappearance of exogenous GCs. No patient developed manifestations of hypocortisolism. CONCLUSIONS: A single 40-mg intrabursal injection of MA or TA is sufficient to suppresses HPAA up to 45 days. Although typically asymptomatic, patients should be instructed to recognize and report symptoms suggestive for hypocortisolism, to provide prompt diagnosis, and eventually, treatment, thus avoiding severe complications.
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Insuficiencia Suprarrenal/patología , Calcinosis/tratamiento farmacológico , Glucocorticoides/efectos adversos , Sistema Hipotálamo-Hipofisario/patología , Artropatías/tratamiento farmacológico , Sistema Hipófiso-Suprarrenal/patología , Articulación del Hombro/patología , Tendinopatía/tratamiento farmacológico , Enfermedades Vasculares/tratamiento farmacológico , Insuficiencia Suprarrenal/inducido químicamente , Biomarcadores/análisis , Estudios de Casos y Controles , Femenino , Estudios de Seguimiento , Glucocorticoides/administración & dosificación , Humanos , Sistema Hipotálamo-Hipofisario/efectos de los fármacos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Sistema Hipófiso-Suprarrenal/efectos de los fármacos , Pronóstico , Método Simple CiegoRESUMEN
The influence of age and sex on chemotherapy-related toxicity was evaluated in children and adults with non metastatic osteosarcoma. treatment consisted of methotrexate (MTX, 12 g/m(2)), cisplatin (CDP 120 mg/m(2)) and doxorubicin (ADM 75-90 mg/m(2)) and high-dose ifosfamide (HDIFO). toxicity data from 1,051 courses (295 with MTX, 756 based on doxorubicin, cisplatin and high-dose ifosfamide) were analyzed. Children (4-14 yrs) and females showed a higher incidence of grade 4 neutropenia and thrombocytopenia and were more frequently hospitalized for neutropenic fever compared to adolescents and young adults (AYA, 15-19 yrs) and adults (>20-40 yrs). Delayed MTX excretion was higher in adults than AYA and children. Adults (up to 40 years) can be treated with pediatric protocols for osteosarcoma and they experience lower hematologic toxicity compared to pediatric population. further investigations on sex-related susceptibility to chemotherapy in osteosarcoma patients are recommended.
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Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Neoplasias Óseas/tratamiento farmacológico , Osteosarcoma/tratamiento farmacológico , Adolescente , Adulto , Factores de Edad , Niño , Preescolar , Cisplatino/administración & dosificación , Cisplatino/efectos adversos , Doxorrubicina/administración & dosificación , Doxorrubicina/efectos adversos , Femenino , Humanos , Ifosfamida/administración & dosificación , Ifosfamida/efectos adversos , Masculino , Metotrexato/administración & dosificación , Metotrexato/efectos adversos , Factores Sexuales , Adulto JovenRESUMEN
Osteosarcoma is the most frequent primary high grade bone tumor, usually occurring in adolescents and children. The aim of the present study was to investigate parameters of bone turnover as urinary excretion of pyridinoline (Pyr), and deoxypyridinoline (D-Pyr), serum osteocalcin (OC), and total alkaline phosphatase (AP) in patients with osteosarcoma. Thirty-five patients aged 7-22 (median age 14) with primary high-grade osteosarcoma of the extremity entered the study. A control population of age- and sex-matched healthy individuals was studied. Urinary excretion of Pyr, D-Pyr was measured on fasting urine specimens, corrected for creatine excretion (Ucr), and expressed as pM/microM UCr. At the same time as urine collection, blood samples were taken for measurement of AP and OC. In patients with osteosarcoma the urinary excretion of D-Pyr (74.5 +/- 41) was significantly higher (P = 0.005) than in controls (38.2 +/- 22.5). The serum level of OC was significantly lower (P < 0.001) in patients with osteosarcoma than in controls. Moreover, significantly (P = 0.03) higher excretion of D-Pyr (85.3 +/- 43) was found in patients who relapsed after surgical removal of the tumor and chemotherapeutic treatment compared with those (58.1 +/- 22) who remained continuously free of disease. The present study showed significant abnormalities of urinary excretion of pyridinium crosslinks and serum OC level in patients with osteosarcoma. The relation between urinary excretion of D-Pyr and biological tumor aggressiveness observed in the present study requires further investigation.
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Aminoácidos/orina , Neoplasias Óseas/metabolismo , Osteocalcina/sangre , Osteosarcoma/metabolismo , Adolescente , Adulto , Fosfatasa Alcalina/sangre , Neoplasias Óseas/patología , Neoplasias Óseas/cirugía , Niño , Femenino , Humanos , Masculino , Recurrencia Local de Neoplasia , Osteosarcoma/secundario , Osteosarcoma/cirugíaRESUMEN
BACKGROUND: Physical activity has been reported to affect endocrine function in elderly men. OBJECTIVE: To establish an association between regular moderate physical activity and endogenous anabolic hormone levels in healthy aging men. PARTICIPANTS: Twenty four middle-aged (57.4+/-4.7 years) and 24 elderly (68.3+/-2.6 years) physically active men who in the past 10 years had been regularly bicycling during leisure time were compared with 24 middle-aged (57.9+/-4.0 years) and 24 elderly (67.2+/-1.7 years) sedentary men. Groups did not differ for body composition. MEASUREMENTS: Serum dehydroepiandrosterone sulfate (DHEAS), insulin-like growth factor-I (IGF-1), free testosterone (FT), and thyroid hormone levels were assessed. RESULTS: In general, elderly men had lower IGF-1 (P<0.001), DHEAS (P=0.013), and triodothyronine levels (P<0.001) than their middle-aged counterparts. Independently of age, however, physically active men had on average higher IGF-1 (P=0.031), DHEAS (P=0.001), and triodothyronine serum levels (P<0.001) than sedentary men. FT and thyroid stimulating hormone (TSH) serum concentrations did not differ across age groups, but physically active men had lower TSH values than sedentary men (P=0.021). CONCLUSIONS: Our results suggest that, in aging men, regular moderate physical activity is associated with higher levels of IGF-1 and DHEAS levels and with thyroid function alterations.
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Envejecimiento/sangre , Envejecimiento/fisiología , Ejercicio Físico/fisiología , Hormonas/sangre , Hormonas Tiroideas/sangre , Anciano , Sulfato de Deshidroepiandrosterona/sangre , Humanos , Factor I del Crecimiento Similar a la Insulina/metabolismo , Masculino , Persona de Mediana Edad , Testosterona/sangre , Triyodotironina/sangreRESUMEN
BACKGROUND: Bone loss in elderly men is associated with changes in body composition and reduced secretion of endogenous anabolizing hormones. The independent influences of body composition and endocrine factors on male bone metabolism, however, are unclear. METHODS: Bone mass density (BMD) (bone mass content [BMC, g]/projected bone area [BA, cm2]) at different skeletal sites, skeletal muscle, and body fat mass were measured by dual-energy X-ray absorptiometry in 129 men aged 20 to 95 years. Free testosterone, 17-beta-estradiol, dehydroepiandrosterone-sulfate, and insulin-like growth factor 1 (IGF-1) serum concentrations were measured. Because BMD may fail to control for differences in skeletal size, the associations of bone mass with body composition and hormones were studied by comparing BMD regression models incorporating age and knee height only with BMC regression models also incorporating BA. RESULTS: Skeletal muscle had close associations (p at least < .01) with BMD and BMC at almost all skeletal sites, but the strength of these associations was generally reduced in BMC with respect to BMD models. Weak associations (p < .05) were found in both models for fatness with femoral bone and for 17-beta-estradiol with total body and femoral bone. The association of 17-beta-estradiol with spinal bone was significant (p < .05) in the BMD but not in the BMC model. No association of BMC or BMD with androgens and IGF-1 reached significancy. CONCLUSIONS: Skeletal muscle may be more important than fatness and anabolizing hormones in preserving bone mass in elderly men. In contrast to traditional belief, estrogens may be more important than androgens and IGF-1 in male bone metabolism.
Asunto(s)
Envejecimiento/fisiología , Andrógenos/sangre , Composición Corporal/fisiología , Densidad Ósea/fisiología , Estrógenos/sangre , Factor I del Crecimiento Similar a la Insulina/análisis , Absorciometría de Fotón , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Envejecimiento/sangre , Anabolizantes/sangre , Índice de Masa Corporal , Sulfato de Deshidroepiandrosterona/sangre , Estradiol/sangre , Fémur/anatomía & histología , Humanos , Articulación de la Rodilla/anatomía & histología , Masculino , Persona de Mediana Edad , Músculo Esquelético/anatomía & histología , Análisis de Regresión , Columna Vertebral/anatomía & histología , Testosterona/sangreRESUMEN
Several micronutrients are involved in thyroid hormone metabolism, but it is unclear whether their marginal deficits may contribute to the alterations in thyroid function observed in extreme aging. The relationships among blood concentrations of thyroid hormones and selenium, zinc, retinol, and alpha-tocopherol were studied in 44 healthy Northern Italian oldest-old subjects (age range, 90-107 yr), selected by the criteria of the SENIEUR protocol. Control groups included 44 healthy adult (age range, 20-65 yr) and 44 SENIEUR elderly (age range, 65-89 yr) subjects. Oldest-old subjects had higher TSH (P < 0.01) and lower free T3 (FT3)/freeT4 (FT4) ratio, zinc, and selenium serum values (P < 0.001) than adult and elderly control subjects. No significant difference was found for plasma retinol and a-tocopherol values. The associations between micronutrients and thyroid hormones were evaluated by multivariate analysis. In oldest-old subjects, plasma retinol was negatively associated with FT4 (P = 0.019) and TSH serum levels (P = 0.040), whereas serum zinc was positively associated with serum FT3 (P = 0.010) and FT3/FT4 ratio (P = 0.011). In younger subjects, no significant association was found among thyroid variables and micronutrients. In conclusion, blood levels of specific micronutrients are associated with serum iodothyronine levels in extreme aging.
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Anciano de 80 o más Años/fisiología , Micronutrientes/análisis , Tirotropina/sangre , Tiroxina/sangre , Oligoelementos/sangre , Triyodotironina/sangre , Adulto , Anciano , Índice de Masa Corporal , Colesterol/sangre , Femenino , Humanos , Recuento de Linfocitos , Masculino , Persona de Mediana Edad , Selenio/sangre , Triglicéridos/sangre , Vitamina A/sangre , Vitamina E/sangre , Zinc/sangreRESUMEN
BACKGROUND: Thermal mud is a therapeutic agent widely used in the treatment of painful arthritic processes. The mechanism by which mud therapy works is still not well known. Its effect continues for months after completion of treatment. In order to verify whether thermal mud treatment brings about changes in the production of hormone peptides from proopiomelanocortin, the levels of plasma beta-endorphin and some hormones of the pituitary-adrenal glands (ACTH and cortisol) were determined in patients affected by osteoarthritis undergoing thermal mud therapy. METHODS: The levels of plasma beta-endorphin and some hormones of the pituitary-adrenal glands (ACTH and cortisol) were assessed by radiometric methods in seventeen males affected by osteoarthritis. The patients underwent a cycle of twelve sessions of thermal mud therapy. The tests were carried out immediately before thermal treatment, immediately after the first session, twelve days after the start of treatment, and again one month after completion of the treatment. RESULTS: beta-endorphin levels decreased significantly twelve days after the start of treatment. The level was still lower, although not significantly, even thirty days after completion of the treatment. Plasma ACTH also decreased during treatment. The decrease of this hormone was progressive and persisted after completion of treatment. Significant variations compared to baseline were found only thirty days after completion of treatment. Plasma cortisol decreased significantly after only one session of mud therapy. This hormone did not decrease any further during treatment, however, after twelve days it was still significantly lower than baseline. After completion of treatment, cortisol slightly increased, but thirty days later it was still lower, although not significantly, than baseline. CONCLUSIONS: It may be suggested that thermal treatment, by reducing inflammation, reduced pain and therefore diminished the cause of stress.
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Hormona Adrenocorticotrópica/sangre , Hidrocortisona/sangre , Peloterapia , Osteoartritis/sangre , Osteoartritis/terapia , betaendorfina/sangre , Anciano , Humanos , Masculino , Persona de Mediana Edad , Sistema Hipófiso-Suprarrenal/metabolismo , Resultado del TratamientoRESUMEN
BACKGROUND: The aim of the study was the assessment of the influence of cytokines on bone ageing by measuring their level in serum and their secretion in vitro by monocytes from women of different age. METHODS: The levels of cytokines in 34 postmenopausal subjects and 14 old subjects were compared to those measured in 13 cycling subjects who were considered as control group. Subjects suffering from diseases inducing secondary osteoporosis, subjects taking medications that affect bone metabolism and alcohol- or tobacco-consumers were excluded from the study. The levels in serum of (i) the bone stimulating peptide insulin-like growth factor-I (IGF-I), (ii) the inhibitor of bone resorption interferon-gamma (IFN gamma), (iii) the stimulators of bone resorption interleukin-1 beta (IL-1 beta) tumor necrosis factor alpha (TNF alpha) and interleukin 6 (IL-6) were evaluated by immunoassay. IL-1 beta, TNF alpha and IL-6 secreted by monocytes (MO) cultured in vitro from peripheral blood of the same subjects were measured, too. Bacterial endotoxin (LPS) was used as stimulator for cytokine secretion by monocytes. RESULTS: Unlike IFN gamma, which was unaltered, circulating IGF-I level was found significantly diminished in postmenopausal and old subjects compared to control group. Among stimulators of bone resorption, IL-6 was greatly increased in postmenopausal and old subjects, while TNF alpha was reduced in postmenopausal group. In the supernatants of unstimulated monocytes the level of IL-1 beta was consistently decreased in old subjects; TNF alpha was found to be decreased in postmenopausal and old subjects. The stimulation index (SI), calculated as the ratio between the level of cytokines secreted by LPS-stimulated MO and the level of cytokines secreted by unstimulated MO, was found to be significantly increased for IL-1 beta and TNF alpha in postmenopausal subjects vs control group. In the old subjects the SI for IL-6 was enhanced. CONCLUSIONS: The data collected suggest that the measurement of cytokines in serum and supernatants from monocytes may give a picture of the mechanisms regulating bone aging.
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Remodelación Ósea/fisiología , Citocinas/sangre , Posmenopausia/fisiología , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Citocinas/biosíntesis , Citocinas/fisiología , Femenino , Humanos , Persona de Mediana Edad , Monocitos/metabolismoRESUMEN
Increasing evidence has demonstrated that the immune system closely interacts with other physiological systems, whose communications are mediated by circulating cytokines and hormones. The aim of our study was to test whether the number and cytolytic activity of NK cells in a group of relatively healthy Italian nonagenarians and centenarians were affected by the modifications of endocrine, metabolic and functional parameters that occur during ageing. Because of the extreme age of the study population, a cross-sectional analysis was performed. This study revealed that the group of oldest subjects with the highest number of NK cells and the best preserved cytolytic function also presented a preserved metabolism of thyroid hormones and vitamin D and integrity of muscle mass. In fact, the NK cell number and/or cytolytic activity of healthy subjects > 90 years old was positively associated with serum levels of vitamin D, while T3, FT4, i-PTH hormones and lean body mass were associated only with NK cell number. In conclusion, our results stress the paramount importance of nutritional evaluation in the clinical assessment of elderly people.
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Anciano de 80 o más Años/fisiología , Células Asesinas Naturales/inmunología , Músculo Esquelético/anatomía & histología , Hormonas Tiroideas/sangre , Vitamina D/sangre , Actividades Cotidianas , Anciano , Estudios Transversales , Femenino , Humanos , Masculino , Estado Nutricional , Tamaño de los Órganos , Grosor de los Pliegues CutáneosRESUMEN
Erythropoietin (EPO) plasma levels were monitored during the perioperative period in 61 consecutive patients (22 males - 39 females), aged 62.5 +/- 9.5 years, scheduled for hip arthroplasty. All patients underwent intraoperative blood salvage (IOBS) and were subdivided into three different groups according to their hemoglobin levels (Hb) 24 hours postoperatively (group A: Hb < 8 g/dl; group B: Hb between 8-9 g/dl; group C: HB > or = 9 g/dl). Seventy-two hours after surgery EPO levels were significantly different in group A (135 +/- 68) compared to group C (54.3 +/- 32), with a positive correlation (p < 0.01) between Hb and EPO levels. On the basis of these results we suggest that a programmed autologous red blood cell collection aimed at obtaining the lowest hemoglobin values during the first 24 hours after surgery, may be of clinical utility in preventing homologous blood needs.
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Artroplastia de Reemplazo de Cadera , Transfusión de Sangre Autóloga/métodos , Eritropoyetina/sangre , Hemodilución/métodos , Anciano , Femenino , Hematócrito , Hemoglobinas/análisis , Humanos , Masculino , Persona de Mediana EdadRESUMEN
The authors evaluated the Insulin-like Growth Factor-1 (IGF-1) stimulating the formation of bone tissue, and interferon gamma (IFN gamma), inhibiting bone resorption, in the serum of women, 13 of fertile age, 34 of post-menopausal age, and 14 of senile age. Values for IGF-1 in the serum were considerably low in patients of post-menopausal and senile age, and presented highly significant differences with values for subjects of fertile age. The values for IFN gamma did not present significant differences between different age groups. It may be assumed that post-menopause and during senile age physiological osteopenia may be favored by a decrease in the secretion of IGF-1.
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Resorción Ósea/sangre , Factor I del Crecimiento Similar a la Insulina/análisis , Interferón gamma/sangre , Adulto , Anciano , Biomarcadores/sangre , Femenino , Humanos , Persona de Mediana EdadRESUMEN
BACKGROUND: The aim of the research was the evaluation of plasmatic protein adsorption on untreated polybutylene terephthalate, corona treated polybutylene terephthalate and polyvinylacetate coated corona treated polybutylene terephthalate. METHODS: Total proteins, albumin, immunoglobulins, fibrinogen, insulin and ostecalcin were determined on plasma after contact with these polymers. RESULTS: Unsignificant variations were observed for the assayed proteins. CONCLUSIONS: The conclusions are drawn that the tested materials do not adsorbe significantly the most important plasmatic proteins.
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Proteínas Sanguíneas/farmacocinética , Poliésteres/química , Adsorción , HumanosRESUMEN
OBJECTIVE: To evaluate the physical ability and psychocognitive status of a population more than 90 years of age with regard to sociodemographic, behavioral, and biomedical variables known to affect functional status in old age. DESIGN: A survey design was used. SETTING: Emilia Romagna, Northern Italy. PARTICIPANTS: Eighty-four healthy community-dwelling subjects aged 90 to 106 years. MEASUREMENTS: Sociodemographic variables, health behavior, anthropometric indices, and serum DHEAS levels were recorded. Functional assessment was performed by instruments currently used in geriatric practice: the Mini-Mental State Examination (MMSE), Geriatric Depression Scale (GDS), and Activities of Daily Living (ADL) scale. A stepwise multiple regression analysis was performed. RESULTS: GDS scores correlated directly with MMSE scores and inversely with ADL severity scores. Poor education, institutionalization, sensory impairment, muscular mass loss, and lower DHEAS levels were the variables with the highest correlation to functional impairment. Smoking, alcohol consumption, and marital status were relatively unimportant. An inverse association was found between DHEAS levels and dependency scores of single ADLs (continence, mobility). CONCLUSION: Impaired cognitive and physical ability with no increase in depression prevalence was found in a sample of subjects more than 90 years of age free of major age-related disease. Muscular mass and DHEAS levels seem to play a role in maintaining physical independence. In turn, physical independence, as well as social and cultural factors, strongly affect the compliance of long-lived subjects with psychocognitive tests currently used in the clinical evaluation of younger old people, suggesting that these instruments are not reliable for screening for cognitive impairment and depression in the oldest old subjects.
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Actividades Cotidianas , Anciano de 80 o más Años , Evaluación Geriátrica , Anciano , Antropometría , Deshidroepiandrosterona/sangre , Depresión/diagnóstico , Femenino , Conductas Relacionadas con la Salud , Humanos , Italia , Masculino , Escala del Estado Mental , Valor Predictivo de las Pruebas , Análisis de Regresión , Reproducibilidad de los Resultados , Factores SocioeconómicosRESUMEN
Dehydroepiandrosterone sulfate (DHEAS), the major circulating adrenal hormone, has been suggested to have a role in many aging related diseases and perhaps in aging itself. Its precise biologic effects are still unknown, and data on healthy people over 90 yr of age are not available. We measured serum DHEAS levels in 75 healthy subjects aged 90-106 yr of both sexes and searched for correlations between DHEAS and several endocrine-metabolic parameters (serum thyroid hormones, GH-insulin-like-growth factor I (GH-IGF-I) axis, serum lipid profile, anthropometric indices of body composition) of the same subjects. The resulting data, normalized by logarithmic transformation (geometric mean at age 90-99, 551 ng/mL in men, 364 ng/mL in women; at age > 100 yr, 404 ng/mL in men, 521 ng/mL in women) resulted five-fold lower than DHEAS levels measured in a young control group (geometric mean at < 40 yr of age, 3110 ng/mL in men, 2824 ng/mL in women). In women over ninety yr, DHEAS was positively correlated with serum free triodothyronine (FT3) levels (r = 0.34, P = 0.05) and inversely with triglycerides (r = -0.45, P = 0.05). In men over 90 yr, DHEAS had positive correlations with body mass index (r = 0.41, P < 0.03) and waist-to-hip ratio (r = 0.47, P < 0.01) taken as indices of body's energy reserves (fat). To determine whether low serum DHEAS levels predict poor functional status in the very old, the Activity Daily Living (ADL) test was administered in all over-ninety subjects. Men with the highest functioning levels had the highest DHEAS levels (P < 0.03). Our data suggest that DHEAS levels may influence and/or be influenced by several endocrine and metabolic features of oldest-old people, depending on the sexual steroid milieu. DHEAS seems also to have a strong interrelation with functional activities. A favorable role for DHEAS in successful aging is proposed.
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Actividades Cotidianas , Anciano de 80 o más Años , Envejecimiento/sangre , Sulfato de Deshidroepiandrosterona/sangre , Glándulas Endocrinas/fisiología , Adulto , Anciano , Constitución Corporal , Índice de Masa Corporal , Humanos , Persona de Mediana Edad , Triglicéridos/sangre , Triyodotironina/sangreRESUMEN
The physiology of aging in very old people is still poorly understood. A wide variety of age-related factors confuse the interpretation of existing data, especially as regards the modifications of the endocrine system. The effect of age on the gonad-hypophyseal function was studied in 26 over ninety-year-old males and compared with a control aged between 27 and 88, subdivided into age groups. The serum levels of total testosterone were stable up to the ninth decade while they were lower in the over ninety-year-olds; free testosterone and its peripheral metabolites (estrogens and dehydrotestosterone) were also lower in the over ninety-year-olds with respect to the others, although the decrease had started more gradually at about the fourth decade. Sex-hormone-binding-globulin, the main serum carrier of testosterone, increased gradually with age. The levels of hypophyseal gonadotropins were constant up to the ninth decade where a significant and abrupt increase was observed. The data suggest the presence of marked alterations of the testicular-hypophyseal axis in the later decades of life, with important repercussions on the pattern of circulating sex steroids.
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Envejecimiento/fisiología , Hormonas Esteroides Gonadales/sangre , Adenohipófisis/metabolismo , Hormonas Adenohipofisarias/sangre , Testículo/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Humanos , Hipogonadismo/fisiopatología , Longevidad , Masculino , Persona de Mediana Edad , Globulina de Unión a Hormona Sexual/análisisRESUMEN
Aged male subjects often have osteoporosis and it has been suggested that the cause is an age-related lack of vitamin D. We evaluated the calcium regulating endocrine mechanism in healthy aged males in order to verify this hypothesis. We studied serum levels of PTH and 1,25(OH)2D in relation to intestinal calcium absorption, radial bone mass density (BMD) and osteocalcin plasma levels in 30 healthy elderly men (61-88 yr.). 1,25(OH)2D levels and calcium absorption, assessed by oral strontium test, did not change with age with respect to a young control group. PTH was higher (p < 0.02) in the elderly than in the control group, and correlated positively with nephrogenous cAMP levels (p < 0.01; r = 0.65). Radial BMD (measured by single photon absorptiometry) was lower (p < 0.01) in elderly than in young subjects and negatively correlated with age (p < 0.01; r = -0.45). Osteocalcin levels, used as a mark of bone turnover, were unchanged. The data suggest that decreased 1,25(OH)2D levels are not a feature of normal male aging. Senile hyperparathyroidism could compensate for impairments in endogenous metabolism of vitamin D in elderly males and maintain calcium absorption at an efficient level, without increasing bone turnover.
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Envejecimiento/metabolismo , Calcio/farmacocinética , AMP Cíclico/sangre , Ergocalciferoles/sangre , Absorción Intestinal , Osteocalcina/sangre , Hormona Paratiroidea/sangre , Adulto , Anciano , Anciano de 80 o más Años , Densidad Ósea , Humanos , Masculino , Persona de Mediana Edad , Osteoporosis/etiología , Valores de Referencia , Estroncio/farmacocinética , Vitamina D/metabolismoRESUMEN
The authors conducted an experimental study on 32 female rats which had been castrated at 10 months of age in order to verify the ability of pulsating electromagnetic fields to prevent osteoporosis induced by surgical menopause. Two different values of intensity of PEMFs were used: 30 G and 70 G. After 4 months of treatment the following testing was done: monophotonic bone densitometry of the lumbar spine, quantitative measurement of the dry ash weight of the femurs, and hematochemical tests to evaluate bone metabolism. The experimental study showed that the PEMFs supplied at 30 Gauss were capable of slowing down the loss of bone mass, while the PEMFs supplied at 70 Gauss obstructed bone decay, providing values for Bone Mineral Density and dry ash weight which were very similar to those observed in the non-castrated control group. Hematochemical tests did not reveal significant variations between the two groups.
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Densidad Ósea/efectos de la radiación , Huesos/efectos de la radiación , Campos Electromagnéticos , Osteoporosis Posmenopáusica/radioterapia , Animales , Huesos/química , Huesos/metabolismo , Modelos Animales de Enfermedad , Relación Dosis-Respuesta en la Radiación , Femenino , Humanos , Osteoporosis Posmenopáusica/metabolismo , Ovariectomía , Ratas , Ratas Sprague-DawleyRESUMEN
We measured calcium regulating hormones and bone mineral density (BMD) in 66 men (aged 24-88 years). Vitamin D (1,25(OH)2D) does not vary with age, parathyroid hormone (PTH) increases after the age of 65 (p < 0.01) together with a parallel increase in urinary (r = 0.46, p < 0.05) and nephrogenic cAMP (r = 0.63, p < 0.01), while BMD decreases with age (r = -0.52, p < 0.01). The finding of age-associated decreases in bone mass even in the presence of constant serum levels of 1,25(OH)2D within the normal range suggests that there is an onset of tissue resistance to vitamin D in the aetiopathogenesis of osteopenia in elderly men.
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Envejecimiento/fisiología , Densidad Ósea/fisiología , Calcitriol/sangre , Calcio/sangre , Hormona Paratiroidea/sangre , Adulto , Anciano , Anciano de 80 o más Años , AMP Cíclico/orina , Humanos , Hidrocortisona/sangre , Masculino , Persona de Mediana Edad , Valores de Referencia , Hormonas Tiroideas/sangreRESUMEN
The authors evaluate the efficacy of salmon calcitonin and aminosuberic analogue of eel calcitonin in the prevention of post-oophorectomy osteoporosis in rats. Both drugs, administered at the same dosage, are equally effective in preventing oophorectomy bone loss in rats. Besides, plasma biochemical evaluations demonstrate that calcitonins reduce bone turnover in treated rats, compared with control oophorectomized ones.
Asunto(s)
Calcitonina/análogos & derivados , Calcitonina/uso terapéutico , Osteoporosis Posmenopáusica/prevención & control , Absorciometría de Fotón , Fosfatasa Alcalina/sangre , Animales , Biomarcadores , Resorción Ósea/prevención & control , Calcitonina/síntesis química , Calcio/sangre , Femenino , Humanos , Osteocalcina/sangre , Ovariectomía/efectos adversos , Fósforo/sangre , Ratas , Ratas Sprague-DawleyRESUMEN
The tetrazolium-based colorimetric assay (MTT test) measures only in vitro living cells and the results are directly related to the number of viable cultured cells. It has been adopted in immunological investigations, cancer research and, recently, biocompatibility evaluation. We used the MTT method with minor modifications to fit it to an in vitro study of biomaterial-cell interactions. The MTT assay was confirmed to be feasible, rapid and reproducible. Moreover, it showed a good correlation with other in vitro proliferation assays, such as the 3H-thymidine uptake assay. By using the MTT method and the ASTM procedure for extracting biomaterials, we quantified the in vitro cell compatibility of different metals and polymers.