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1.
Acta Endocrinol (Buchar) ; 17(3): 304-312, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35342466

RESUMO

Context: Exercise and anabolic steroids are anticipated to promote fat mass reduction and so to decrease the number of comorbidities related to excessive weight. Objective: The aim of this study was to verify the influence of aerobic exercise and the use of steroids on the accumulation of adipose tissue and on the biochemical limitations of Wistar rats nourished by a hypercaloric diet. Methods: Forty, young male Wistar rats were split into four groups: obese control (n=10), obese under treatment (n=10), obese under aerobic exercise (n=10) and obese under aerobic exercise and treatment (n=10). All animals were fed with a hypercaloric diet and animals under treatment received intramuscular testosterone. Body (weight and visceral fat) and blood (lipidogram, glucose, and liver enzymes) parameters were assessed. Results: The group treated with aerobic exercise and testosterone revealed a reduction in body weight and visceral, perirenal, retroperitoneal and epididymal fats, accompanied by the blood levels of glucose, lactate, LDL-cholesterol, HDL-cholesterol, and lactate dehydrogenase; following high-intensity physical activity. Conclusion: The results support the theory that the combination of steroids and physical activity reduces the side-effects of androgenic-anabolic hormones and conveys benefits to some constraints.

2.
Calcif Tissue Int ; 87(1): 52-9, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20383765

RESUMO

Low-intensity electrical stimulation (LIES) may counteract the effects of ovariectomy (OVX) on nitric oxide synthase (NOS) expression, osteocyte viability, bone structure, and microarchitecture in rats (Lirani-Galvão et al., Calcif Tissue Int 84:502-509, 2009). The aim of the present study was to investigate if these effects of LIES could be mediated by NO. We analyzed the effects of NO blockage (by L-NAME) in the response to LIES on osteocyte viability, bone structure, and microarchitecture in OVX rats. Sixty rats (200-220 g) were divided into six groups: sham, sham-L-NAME (6 mg/kg/day), OVX, OVX-L-NAME, OVX-LIES, and OVX-LIES-L-NAME. After 12 weeks, rats were killed and tibiae collected for histomorphometric analysis and immunohistochemical detection of endothelial NOS (eNOS), inducible NOS (iNOS), and osteocyte apoptosis (caspase-3 and TUNEL). In the presence of L-NAME, LIES did not counteract the OVX-induced effects on bone volume and trabecular number (as on OVX-LIES). L-NAME blocked the stimulatory effects of LIES on iNOS and eNOS expression of OVX rats. Both L-NAME and LIES decreased osteocyte apoptosis. Our results showed that in OVX rats L-NAME partially blocks the effects of LIES on bone structure, turnover, and expression of iNOS and eNOS, suggesting that NO may be a mediator of some positive effects of LIES on bone.


Assuntos
Óxido Nítrico/metabolismo , Animais , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Osso e Ossos/metabolismo , Caspase 3 , Feminino , Marcação In Situ das Extremidades Cortadas , NG-Nitroarginina Metil Éster/farmacologia , Óxido Nítrico Sintase/metabolismo , Óxido Nítrico Sintase Tipo II , Óxido Nítrico Sintase Tipo III/metabolismo , Osteócitos/metabolismo , Osteócitos/fisiologia , Ovariectomia , Ratos , Ratos Wistar
3.
Calcif Tissue Int ; 84(6): 502-9, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19458889

RESUMO

Low Intensity Electrical Stimulation (LIES) has been used for bone repair, but little is known about its effects on bone after menopause. Osteocytes probably play a role in mediating this physical stimulus and they could act as transducers through the release of biochemical signals, such as nitric oxide (NO). The aim of the present study was to investigate the effects of LIES on bone structure and remodeling, NOS expression and osteocyte viability in ovariectomized (OVX) rats. Thirty rats (200-220 g) were divided into 3 groups: SHAM, OVX, and OVX subjected to LIES (OVX + LIES) for 12 weeks. Following the protocol, rats were sacrificed and tibias were collected for histomorphometric analysis and immunohistochemical detection of endothelial NO synthase (eNOS), inducible NOS (iNOS), and osteocyte apoptosis (caspase-3 and TUNEL). OVX rats showed significant (p < 0.05 vs. SHAM) decreased bone volume (10% vs. 25%) and trabecular number (1.7 vs. 3.9), and increased eroded surfaces (4.7% vs. 3.2%) and mineralization surfaces (15.9% vs. 7.7%). In contrast, after LIES, all these parameters were significantly different from OVX but not different from SHAM. eNOS and iNOS were similarly expressed in subperiosteal regions of tibiae cortices of SHAM, not expressed in OVX, and similarly expressed in OVX + LIES when compared to SHAM. In OVX, the percentage of apoptotic osteocytes (24%) was significantly increased when compared to SHAM (11%) and OVX + LIES (8%). Our results suggest that LIES counteracts some effects of OVX on bone tissue preserving bone structure and microarchitecture, iNOS and eNOS expression, and osteocyte viability.


Assuntos
Osso e Ossos/fisiologia , Terapia por Estimulação Elétrica , Menopausa , Óxido Nítrico/metabolismo , Osteócitos/fisiologia , Animais , Apoptose/fisiologia , Osso e Ossos/metabolismo , Osso e Ossos/ultraestrutura , Caspase 3/metabolismo , Sobrevivência Celular/fisiologia , Feminino , Óxido Nítrico Sintase Tipo II/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Osteócitos/metabolismo , Osteócitos/ultraestrutura , Ovariectomia , Ratos , Ratos Wistar , Tíbia/citologia , Tíbia/fisiologia
4.
Braz J Med Biol Res ; 39(11): 1501-5, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17146563

RESUMO

Osteoporosis and its consequent fractures are a great social and medical problem mainly occurring in post-menopausal women. Effective forms of prevention and treatment of osteoporosis associated with lower costs and the least side effects are needed. Electrical fields are able to stimulate osteogenesis in fractures, but little is known about their action on osteoporotic tissue. The aim of the present study was to determine by bone densitometry the effects of electrical stimulation on ovariectomized female Wistar rats. Thirty rats (220 +/- 10 g) were divided into three groups: sham surgery (SHAM), bilateral ovariectomy (OVX) and bilateral ovariectomy + electrical stimulation (OVX + ES). The OVX + ES group was submitted to a 20-min session of a low-intensity pulsed electrical field (1.5 MHz, 30 mW/cm(2)) starting on the 7th day after surgery, five times a week (total = 55 sessions). Global, spine and limb bone mineral density were measured by dual-energy X-ray absorptiometry (DXA Hologic 4500A) before surgery and at the end of protocol (84 days after surgery). Electrical stimulation improved (P < 0.05) global (0.1522 +/- 0.002), spine (0.1502 +/- 0.003), and limb (0.1294 +/- 0.003 g/cm(2)) bone mineral density compared to OVX group (0.1447 +/- 0.001, 0.1393 +/- 0.002, and 0.1212 +/- 0.001, respectively). The OVX + ES group also showed significantly higher global bone mineral content (9.547 +/- 0.114 g) when compared to both SHAM (8.693 +/- 0.165 g) and OVX (8.522 +/- 0.207 g) groups (P < 0.05). We have demonstrated that electrical fields stimulate osteogenesis in ovariectomized female rats. Their efficacy in osteoporosis remains to be demonstrated.


Assuntos
Densidade Óssea , Terapia por Estimulação Elétrica , Osteogênese/fisiologia , Osteoporose/terapia , Absorciometria de Fóton , Animais , Modelos Animais de Doenças , Feminino , Ovariectomia , Ratos , Ratos Wistar , Fatores de Tempo
5.
Braz. j. med. biol. res ; 39(11): 1501-1505, Nov. 2006. graf, tab
Artigo em Inglês | LILACS | ID: lil-437830

RESUMO

Osteoporosis and its consequent fractures are a great social and medical problem mainly occurring in post-menopausal women. Effective forms of prevention and treatment of osteoporosis associated with lower costs and the least side effects are needed. Electrical fields are able to stimulate osteogenesis in fractures, but little is known about their action on osteoporotic tissue. The aim of the present study was to determine by bone densitometry the effects of electrical stimulation on ovariectomized female Wistar rats. Thirty rats (220 ± 10 g) were divided into three groups: sham surgery (SHAM), bilateral ovariectomy (OVX) and bilateral ovariectomy + electrical stimulation (OVX + ES). The OVX + ES group was submitted to a 20-min session of a low-intensity pulsed electrical field (1.5 MHz, 30 mW/cm²) starting on the 7th day after surgery, five times a week (total = 55 sessions). Global, spine and limb bone mineral density were measured by dual-energy X-ray absorptiometry (DXA Hologic 4500A) before surgery and at the end of protocol (84 days after surgery). Electrical stimulation improved (P < 0.05) global (0.1522 ± 0.002), spine (0.1502 ± 0.003), and limb (0.1294 ± 0.003 g/cm²) bone mineral density compared to OVX group (0.1447 ± 0.001, 0.1393 ± 0.002, and 0.1212 ± 0.001, respectively). The OVX + ES group also showed significantly higher global bone mineral content (9.547 ± 0.114 g) when compared to both SHAM (8.693 ± 0.165 g) and OVX (8.522 ± 0.207 g) groups (P < 0.05). We have demonstrated that electrical fields stimulate osteogenesis in ovariectomized female rats. Their efficacy in osteoporosis remains to be demonstrated.


Assuntos
Animais , Feminino , Ratos , Densidade Óssea , Terapia por Estimulação Elétrica , Osteogênese/fisiologia , Osteoporose/terapia , Absorciometria de Fóton , Modelos Animais de Doenças , Ovariectomia , Ratos Wistar , Fatores de Tempo
7.
Horm Metab Res ; 24(9): 439-43, 1992 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-1427616

RESUMO

The molecular heterogeneity of serum immunoreactive calcitonin (iCT) was analyzed from a prospective study of 41 burn patients. Using different region-specific anticalcitonin antisera, the ratio of mid-region-recognizing to carboxyl terminal-region-recognizing iCT was found to increase acutely in those who subsequently died. The highest ratios occurred in those who died early of respiratory complications. Sephadex chromatography and reversed-phase HPLC demonstrated that the serum iCT circulated predominantly in the large molecular mass prohormone form (16 kDa). In comparison, iCT of normal human lung and of normal thyroid was shown to consist primarily of smaller monomeric mass forms. Furthermore, in 12 normal volunteers who were evaluated with a calcium-pentagastrin infusion, the ratio of iCT levels did not differ from the baseline ratio despite a 50% increase in serum iCT. These results suggest that in burns, the inhalational injury-associated hypercalcitonemia is characterized by a preferential release of procalcitonin; a form of constitutive secretion. The measurement of serum procalcitonin levels would appear to be a useful prognostic indicator of the severity of inhalational injury occurring in burn patients.


Assuntos
Queimaduras por Inalação/sangue , Calcitonina/sangue , Precursores de Proteínas/sangue , Biomarcadores , Peptídeo Relacionado com Gene de Calcitonina , Cromatografia em Gel , Cromatografia Líquida de Alta Pressão , Humanos , Prognóstico , Radioimunoensaio
9.
Lab Invest ; 51(1): 39-45, 1984 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-6737995

RESUMO

Immunoreactive calcitonin (iCT) has been localized in solitary endocrine cells and in clusters of these cells, called neuroepithelial bodies, in human and hamster lungs. It has been demonstrated that hyperplasia of hamster lung endocrine cells occurs following exposure to diethylnitrosamine (DEN), a systemic carcinogen. In the present study we have investigated iCT as a hormonal correlate of DEN-induced pulmonary endocrine cell hyperplasia in hamsters. Hamsters were given 3 mg of DEN per animal, subcutaneously, twice a week and then serially sacrificed at 2, 4, 8, and 12 weeks. By immunocytochemistry, iCT-containing cells could be demonstrated in thyroids, tracheal glands, and throughout the airway epithelium. At 8 or 12 weeks of DEN exposure, one to eight neuroepithelial bodies with iCT-containing cells were identified per square centimeter of lung sections, in contrast to zero to one neuroepithelial bodies/cm2 in control hamsters. By radioimmunoassay, pulmonary iCT increased significantly at 8 weeks of DEN exposure, amounting to 3.5-fold the control values at 12 weeks. Serum iCT increased at 4 weeks of exposure and by 12 weeks had tripled (183 +/- 62 pg/ml, mean +/- SD, p less than 0.001), as compared with control animals. Subsequently, DEN was stopped for 4 weeks, and the levels of both serum and lung iCT decreased, although they remained higher than those of controls. The serum and lung iCT of control hamsters was constant throughout the experiment (49 +/- 26 pg/ml and 1754 +/- 489 pg/gm of wet weight, mean +/- SD, respectively). Thyroidal iCT levels of exposed hamsters did not differ from those of the controls; both increased progressively. The DEN-exposed animals had retarded growth as compared with the controls. Column chromatography using superfine Sephadex G-75 demonstrated that both DEN-exposed and control lungs contained iCT with a predominant molecular size corresponding to the dimer of synthetic human calcitonin; whereas thyroidal iCT was mostly monomeric (approximately 3,500 daltons). The increase of pulmonary iCT correlates well with the 4-fold increase of pulmonary endocrine cells, reported earlier following similar DEN exposure. We conclude that iCT levels of hamster sera and lungs can be used as a biochemical parameter to monitor hyperplasia of the pulmonary endocrine cells in these animals.


Assuntos
Calcitonina/análise , Dietilnitrosamina , Glândulas Endócrinas/patologia , Pulmão/patologia , Nitrosaminas , Animais , Cricetinae , Glândulas Endócrinas/análise , Hiperplasia , Pulmão/análise , Pulmão/efeitos dos fármacos , Masculino , Mesocricetus , Radioimunoensaio , Glândula Tireoide/análise
10.
Cancer Lett ; 18(2): 179-85, 1983 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-6299519

RESUMO

A study was made of immunoreactive calcitonin (iCT) secretion by continuous cultures of small cell carcinoma of the lung (SCCL). Using an antiserum region specific for the midportion of the molecule, 9/12 cultures were found to secrete iCT. Gel filtration studies were performed on both supernatant fluid (SF) and cell pellet (CP) extract from a culture secreting high levels of iCT. Multiple iCT fractions were found in the SF with the major fraction being of high molecular weight (MW). In contrast, the CP had apparently monomeric CT as its principal iCT fraction. These studies demonstrate frequent iCT secretion by SCCL cultures and significant disparities between the iCT moieties found extra- and intracellularly.


Assuntos
Calcitonina/metabolismo , Carcinoma de Células Pequenas/metabolismo , Neoplasias Pulmonares/metabolismo , Animais , Calcitonina/imunologia , Células Cultivadas , Cromatografia em Gel , Humanos , Camundongos , Camundongos Nus , Peso Molecular , Transplante de Neoplasias
13.
Med Hypotheses ; 7(7): 943-9, 1981 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-6270516

RESUMO

The bronchial Kulchitsky cells are scattered specific cells which lie close to the basement membrane of the bronchi and bronchioles. Electron microscopy reveals that they contain electron-dense granules similar to that seen in cells with a known endocrine function. In addition, experimentally induced degranulation of the K cell suggestive of a secretory process, and the likelihood that these cells are precursors of small cell lung carcinoma (which often elaborates humoral substances) has led to the postulate that this bronchial cell serves a humoral role of either a paracrine or endocrine nature. We have found that the bronchial K cell of man contains a calcitonin-like polypeptide which, immunologically and chemically, is not dissimilar to the hormone produced by the C cells of human thyroid. This finding may help explain the persistence of serum immunoreactive calcitonin (iCT) after total thyroidectomy, the fact that thyroidectomized man does not manifest any profound alteration of calcium metabolism, and why small cell cancer of the lung is frequently associated with hypercalcitonemia. In addition, the finding of K cell hyperplasia in chronic bronchitis and emphysema may explain the occurrence of hypercalcitonemia in patients with these diseases and some lung cancers of cell types other than the small cell variety. Further studies are needed to elucidate the role of K cell iCT, and to determine what other hormones might also be elaborated by this diffuse system of bronchial cells.


Assuntos
Brônquios/citologia , Sistema Cromafim/metabolismo , Calcitonina/análise , Calcitonina/metabolismo , Carcinoma de Células Pequenas/complicações , Carcinoma de Células Pequenas/patologia , Sistema Cromafim/análise , Sistema Cromafim/citologia , Humanos , Hipercalcemia/complicações , Neoplasias Pulmonares/complicações , Neoplasias Pulmonares/patologia
15.
Chest ; 79(2): 211-6, 1981 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7006935

RESUMO

Serum and urinary calcitonin levels were measured in patients with acute and chronic inflammatory diseases of the lung. Using both carboxyl terminal and midportion antisera, the incidence of increased immunoreactive values of this hormone was 68 percent for patients with emphysema, 59 percent for tuberculosis, and 89 percent for acute bacterial pneumonitis. In order to determine the source of the high levels of calcitonin, immunoperoxidase stains were made of sections of human lung; the hormone was found within the bronchial Kultschitzky cell (K cell). This suggests a specific endocrine role for the K cell, and may explain not only the high calcitonin levels in patients with inflammatory lung disease, but also the high levels associated with both carcinoid tumor and small cell carcinoma, which may originate from K cells. It is apparent that moderately high levels of calcitonin in a patient with pulmonary disease cannot always be associated with tumor.


Assuntos
Calcitonina/metabolismo , Pneumopatias/metabolismo , Adulto , Feminino , Humanos , Técnicas Imunoenzimáticas , Pulmão/análise , Masculino , Radioimunoensaio
16.
Acta Orthop Scand ; 52(2): 191-5, 1981.
Artigo em Inglês | MEDLINE | ID: mdl-7246097

RESUMO

"Observation Hip" is a provisional diagnosis. Although transient arthritis is the most frequent pathology, it is important to establish a diagnostic routine to consider the various types of hip pathology. Physical examination and clinical evolution are the most important factors in making a specific diagnosis.


Assuntos
Artrite/diagnóstico , Articulação do Quadril , Artrite/patologia , Criança , Diagnóstico Diferencial , Feminino , Marcha , Humanos , Lactente , Masculino , Membrana Sinovial/patologia , Sinovite/diagnóstico
17.
J Natl Med Assoc ; 73(7): 649-52, 1981.
Artigo em Inglês | MEDLINE | ID: mdl-7265273

RESUMO

Calcitonin, the hypocalcemic, hypophosphatemic polypeptide hormone of C cell origin, has been reported to be high in pregnant women at delivery. Levels of this hormone were determined by radioimmunoassay in 56 pregnant women in all trimesters and found to be above normal in 72 percent. Values were also increased during the first two days postpartum. Calcitonin levels were not correlated with serum calcium or phosphate, except in the first trimester when levels of this hormone were inversely correlated with serum phosphate. Perhaps the hypercalcitonemia of pregnancy serves to protect the maternal skeleton, while allowing the fetus to accumulate calcium.


Assuntos
Calcitonina/sangue , Complicações na Gravidez , Adulto , Cálcio/sangue , Feminino , Humanos , Fosfatos/sangue , Gravidez
18.
Experientia ; 36(11): 1330-1, 1980 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-7449924

RESUMO

Gastrin has been suggested as a natural secretogogue of the hormone calcitonin. We have found hypercalcitonemia in 55% of patients with pernicious anemia, and the gastrin levels, although usually increased, did not correlate.


Assuntos
Anemia Perniciosa/fisiopatologia , Calcitonina/sangue , Gastrinas/sangue , Cálcio/sangue , Humanos , Valores de Referência
19.
Brain Res ; 194(2): 598-602, 1980 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-7388636

RESUMO

We have detected immunoreactive calcitonin (iCT) in the cerebrospinal fluid (CSF) of normal individuals. Using an antibody with midportion recognition, the mean +/- S.D. of the cerebrospinal iCT in 27 normal subjects was 28 +/- 14 pg/ml. The mean serum iCT was 89 +/- 68 pg/ml, the CSF/serum distribution ratio being 0.31. There were no significant correlations between CSF iCT or serum iCT and the calcium, magnesium, phosphate, sodium, potassium or chloride in the CSF or serum. Although there was a trend for serum iCT values to be related to CSF iCT values, it did not attain statistical significance. The demonstration that the CSF contains iCT may have important physiologic implications, and its measurement offers a useful parameter to study its effects on calcium metabolism and/or other aspects of brain function.


Assuntos
Calcitonina/líquido cefalorraquidiano , Adulto , Cálcio/líquido cefalorraquidiano , Proteínas do Líquido Cefalorraquidiano/metabolismo , Cloretos/líquido cefalorraquidiano , Feminino , Humanos , Magnésio/líquido cefalorraquidiano , Masculino , Pessoa de Meia-Idade , Fosfatos/líquido cefalorraquidiano , Potássio/líquido cefalorraquidiano , Radioimunoensaio , Sódio/líquido cefalorraquidiano
20.
Am J Med Sci ; 280(1): 11-5, 1980.
Artigo em Inglês | MEDLINE | ID: mdl-7424966

RESUMO

A comparative study was made of the serum calcitonin levels of patients with hyperparathyroidism. The mean serum calcitonin of those with hyperparathyroidism did not differ significantly from normal persons (mean +/- SEM: 130 +/- 16 pg/ml vs 124 +/- 7 pg/ml, respectively.) Only 0.5% of patients with hyperparathyroidism had values exceeding the upper limits of normal. In contrast, the mean serum calcitonin of patients with hypercalcemia of nonparathyroid etiology was considerably higher than normal (354 +/- 75 pg/ml, p < 0.001)), and 41% exceeded the upper limits of normal. Calcium infusion induced less of an increase in serum calcitonin for patients with hyperparathyroidism than for normal persons. In addition, the diminished responsibility was also present postoperatively. These findings suggest that the prolonged hypercalcemia associated with hyperparathyroidism results in a decreased calcitonin reserve which may persist for unknown reasons. In the clinical evaluation of hypercalcemic patient, the finding of hypercalcitonemia is suggestive evidence against the diagnosis of hyperparathyroidism.


Assuntos
Calcitonina/sangue , Hiperparatireoidismo/sangue , Cálcio/sangue , Feminino , Humanos , Hipercalcemia/sangue , Masculino , Glândula Tireoide/metabolismo , Neoplasias da Glândula Tireoide/sangue
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