Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 33
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Exp Clin Endocrinol Diabetes ; 115(7): 428-32, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17647139

RESUMO

Hypercholesterolemia is a major risk factor for atherosclerosis. Dysregulation of adipokines contribute to atherosclerotic diseases. Apelin has recently been shown to be secreted by the adipose tissue in association with hyperinsulinemia and inflammation. We searched plasma apelin levels in patients with elevated low density lipoprotein (LDL)-cholesterol having no additional disorder. Thirty-three patients with hypercholesterolemia and 50 age-, sex-, and body mass index-matched healthy controls were evaluated for their apelin, adiponectin and high sensitivity C-reactive protein (hsCRP) levels, and homeostasis model assessment (HOMA) indexes. Plasma apelin-12 and adiponectin were determined by ELISA and RIA, respectively. Plasma apelin levels were lower in patients with elevated LDL-cholesterol compared to healthy controls (p<0.001). Plasma adiponectin concentration was also lower in the dyslipidemic patients (p<0.001). hsCRP levels were similar in the two groups. Fasting plasma glucose was normal in both groups. HOMA indexes in the dyslipidemic group were higher than the controls (p=0.005). A mild to moderate negative correlation with HOMA and positive correlation with high density lipoprotein cholesterol of apelin was found in the dyslipidemic group. Plasma apelin is decreased in non-obese, non-diabetic and normotensive patients with elevated LDL-cholesterol. Low apelin levels in hypercholesterolemia seem associated with insulin resistance, which needs to be investigated in larger populations as well as in other atherosclerotic conditions.


Assuntos
LDL-Colesterol/sangue , Hipercolesterolemia/sangue , Peptídeos e Proteínas de Sinalização Intercelular/sangue , Adiponectina/sangue , Adulto , Idoso , Apelina , Glicemia/análise , Índice de Massa Corporal , Proteína C-Reativa/análise , Estudos de Casos e Controles , Feminino , Humanos , Resistência à Insulina , Masculino , Pessoa de Meia-Idade , Triglicerídeos/sangue
3.
Clin Nephrol ; 64(1): 12-9, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16047640

RESUMO

AIMS: Adiponectin seems to be an important modulator for metabolic and vascular diseases. We aimed to measure plasma adiponectin levels in type 2 diabetic patients and investigate any association with the severity of proteinuria. METHODS: 80 patients (mean age, 46.9 +/- 5.1 years; body mass index (BMI), 25.8 +/- 1.98 kg/m2) and 47 healthy volunteers (mean age, 46.1 +/- 5.5 years; BMI 26.74 +/- 2.23 kg/m2) were included. Plasma adiponectin concentration, insulin levels, homeostasis model assessment (HOMA) indices, calculated glomerular filtration rate (GFR), high sensitive C reactive protein (hsCRP) and biochemistry panel were determined in all subjects. The association between adiponectin concentration and proteinuria was evaluated. Additionally, the relationship between adiponectin and hsCRP and calculated GFR were also investigated. RESULTS: Adiponectin levels in patients were significantly lower than those of controls (n = 80; 8.76 +/- 4.50 microg/ml for patients, n = 47; 24.27 +/- 5.59 microg/ml for controls, p < 0.001). Plasma adiponectin levels in patients with proteinuria were significantly lower than those without proteinuria (n = 43; 6.81 +/- 2.82 microg/ml for proteinuria, n = 37; 11.98 +/- 3.32 microg/ml for no proteinuria, p < 0.001). There was a significant negative correlation between plasma adiponectin concentrations and the degree of proteinuria (r = -0.433, p < 0.001). There were also significant negative correlations between adiponectin concentrations and insulin levels as well as HOMA index in the patient group (r = -0.322, p = 0.004; r = -0.301, p = 0.032). Additionally there was a significant negative correlation between adiponectin and hsCRP levels in the patient group (r = -0.872, p < 0.001). CONCLUSION: The results show that adiponectin is lower in patients with type 2 diabetes and the levels are negatively correlated with the severity of proteinuria.


Assuntos
Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/urina , Peptídeos e Proteínas de Sinalização Intercelular/sangue , Proteinúria/sangue , Adiponectina , Proteína C-Reativa/metabolismo , Estudos de Casos e Controles , Distribuição de Qui-Quadrado , Estudos Transversais , Feminino , Homeostase , Humanos , Insulina/sangue , Resistência à Insulina , Masculino , Pessoa de Meia-Idade , Estatísticas não Paramétricas
4.
Addict Biol ; 7(2): 255-8, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12006222

RESUMO

In this study, the effects of cigarettes with differing tar content on erythrocyte oxidant/antioxidant status was investigated. Malondialdehyde (MDA) as an indicator of oxidant status and superoxide radical scavenger activity (SSA) as an indicator of antioxidant status were measured in erythrocytes from 20 smokers and 10 non-smoker controls. Ten of the 20 smoking subjects smoked five cigarettes with full flavour low tar (FFLT with 12 mg tar) and the others smoked five cigarettes with full flavour high tar (FF with 23 mg tar) over 1 hour. Initial blood samples from both groups at fasting, followed by further samples from smokers at 1.5 hours and 3 hours after smoking. Initial erythrocyte MDA level and SSA activity were found to be higher in the smoking groups compared to non-smokers. Furthermore, both parameters were significantly higher at the 1.5-hour and 3-hour erythrocyte samples when compared to initial values in the FFLT group. However, there were no statistically significant differences between SSA values established at different times in FF group. Results suggest that smoking causes oxidant load in the erythrocytes. Although a compensatory mechanism (i.e. increased SSA activities) develops in the FFLT group after smoking, this cannot prevent peroxidation reactions (i.e. increased MDA levels) in the erythrocytes. As to the types of cigarettes, both seem to have oxidant potential, but oxidation degree in the FFLT group is higher than that of FF group. These results suggest that antioxidant supplementation to smokers might be beneficial to decrease cellular oxidation damages.


Assuntos
Antioxidantes/metabolismo , Eritrócitos/efeitos dos fármacos , Malondialdeído/sangue , Fumar/efeitos adversos , Alcatrões/efeitos adversos , Adulto , Relação Dose-Resposta a Droga , Humanos , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Militares , Valores de Referência , Fumar/sangue , Alcatrões/farmacologia
5.
Obes Res ; 9(11): 662-7, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11707532

RESUMO

OBJECTIVE: The aim of this study was to investigate the effects of combined hypocaloric diet and metformin on circulating testosterone and leptin levels in obese men with or without type 2 diabetes. RESEARCH METHODS AND PROCEDURES: Twenty obese men with type 2 diabetes (mean body mass index [BMI]: 35.5 +/- 1.1 kg/m(2)) and 20 nondiabetic obese men were enrolled in the study. We measured serum follicle-stimulating hormone, luteinizing hormone (LH), total testosterone (TT), free testosterone (FT), sex-hormone-binding globulin (SHBG), dehydroepiandrosterone sulfate (DHEAS), and plasma leptin levels before and 3 months after metformin treatment. Both groups were placed on a hypocaloric diet and 850 mg of metformin taken orally twice daily for 3 months. RESULTS: Metformin and hypocaloric diets led to decreases in BMI and waist and hip circumferences in both groups. A significant decrease in TT levels in the diabetic group and FT levels in the control group was found, whereas follicle-stimulating hormone, LH, and DHEAS levels were not changed significantly. A significant increase in SHBG levels was observed in the control group but not in the patient group. Leptin levels also decreased after treatment in both groups. Decreased testosterone levels were not correlated to changes in waist and hip circumference, waist-to-hip ratio, BMI, and levels of fasting blood glucose, leptin, SHBG, or DHEAS in the diabetic group. However, a decrease in FT was correlated to changes in the levels of SHBG (r = -0.71, p = 0.001) and LH (r = 0.80, p = 0.001) but not to other parameters. DISCUSSION: We conclude that metformin treatment combined with a hypocaloric diet leads to reduced FT levels in obese nondiabetic men and to reduced TT levels in obese men with type 2 diabetes. Increased SHBG levels may account for the decrease in FT levels in the former group.


Assuntos
Dieta Redutora , Hipoglicemiantes/farmacologia , Leptina/metabolismo , Metformina/farmacologia , Obesidade/sangue , Testosterona/sangue , Adulto , Constituição Corporal , Índice de Massa Corporal , Sulfato de Desidroepiandrosterona/sangue , Diabetes Mellitus/sangue , Diabetes Mellitus/terapia , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/terapia , Ingestão de Energia , Feminino , Hormônio Foliculoestimulante/sangue , Humanos , Hipoglicemiantes/uso terapêutico , Hormônio Luteinizante/sangue , Masculino , Metformina/uso terapêutico , Pessoa de Meia-Idade , Obesidade/terapia , Globulina de Ligação a Hormônio Sexual/análise
6.
J Clin Endocrinol Metab ; 86(8): 3659-64, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11502793

RESUMO

Acylation-stimulating protein is an adipocyte-derived protein that has recently been suggested to play an important role in the regulation of triglyceride storage. To date, little information has been reported with regard to fasting acylation-stimulating protein levels and its relation to metabolic control, leptin, and/or lipids in subjects with diabetes mellitus. We therefore evaluated fasting acylation-stimulating protein, leptin, and lipid levels before and 4 months after improving glycemic control with sulfonylurea treatment in a group of poorly controlled obese women with type 2 diabetes and in age- and body mass index-matched nondiabetic obese women. Fasting plasma acylation-stimulating protein (49.67 +/- 19.73 vs. 48.49 +/- 20.70 nmol/liter) and leptin concentrations (33.7 +/- 23.2 vs. 26.2 +/- 10.6 ng/ml) were not significantly different between the groups. Improvement of glycemic control produced parallel falls in fasting blood glucose and hemoglobin A1c. Plasma leptin concentrations were also significantly reduced (33.69 +/- 23.2 vs. 22.73 +/- 11.26 ng/ml; P = 0.036), whereas fasting acylation-stimulating protein concentrations were significantly increased after treatment (48.49 +/- 20.70 vs. 72,82 +/- 29,72 nmol/liter; P = 0.004). Nevertheless, lipids and apolipoprotein B did not significantly improve. We could not find any correlation between elevated acylation-stimulating protein levels and changes in body mass index, glucose, insulin, hemoglobin A1c, leptin, or lipid levels. Similarly, the decrement in circulating leptin levels observed after treatment did not correlate with changes in the levels of glucose, insulin, hemoglobin A1c, or any lipid parameters. We conclude that improved glycemic control increases fasting acylation-stimulating protein and decreases leptin concentrations, but not corrects critical lipid abnormalities in type 2 obese diabetic subjects. Moreover, altered plasma acylation-stimulating protein levels are not associated with changes in body mass index or lipid, leptin, insulin, or glucose levels. Thus, our findings suggest that improved glycemic control or insulin resistance is not responsible for abnormal fatty acid trapping, and failure of lipids to improve after treatment in our patients is consistent with the acylation-stimulating protein resistance concept.


Assuntos
Glicemia/metabolismo , Proteínas Sanguíneas/metabolismo , Complemento C3a/análogos & derivados , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus/sangue , Leptina/sangue , Obesidade/sangue , Apolipoproteína A-I/sangue , Apolipoproteínas B/sangue , Biomarcadores/sangue , Pressão Sanguínea , Colesterol/sangue , HDL-Colesterol/sangue , LDL-Colesterol/sangue , VLDL-Colesterol/sangue , Diabetes Mellitus/tratamento farmacológico , Diabetes Mellitus/fisiopatologia , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/fisiopatologia , Jejum , Hemoglobinas Glicadas/análise , Humanos , Hipoglicemiantes/uso terapêutico , Insulina/sangue , Pessoa de Meia-Idade , Obesidade/fisiopatologia , Compostos de Sulfonilureia/uso terapêutico , Triglicerídeos/sangue
7.
Med Sci Monit ; 7(4): 696-700, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11433197

RESUMO

BACKGROUND: Recent studies have demonstrated that human preadipocyte fibroblasts in orbital connective tissues from patients with Graves' ophthalmopathy differentiate into cells resembling adipocytes and acquire expression of leptin and functional thyroid stimulating hormone receptors. These finding imply that leptin may play a role in the pathogenesis of Graves' ophthalmopathy. However, little is known about plasma leptin concentration in patients with Graves' disease with or without ophthalmopathy. MATERIAL AND METHODS: To investigate this relationship; 28 patients with active Graves' ophthalmopathy (19 female and 9 male, mean age: 32.7+/-10.5 years, mean BMI: 24.8+/-3.7 kg/m2) and 10 patients without ophthalmopathy (6 female and 4 male, mean age: 24.6+/-5.6, mean BMI: 23.02+/-2.4 kg/m2) all with untreated Graves' disease were included in the study at first diagnosis in our endocrinology out-patient clinic. Sex-, BMI- and age-matched twenty healthy subjects (13 female, 7 male, mean age: 31.9+/-10.0, mean BMI: 24.2+/-3.0 kg/m2) were selected as a control group. Plasma leptin levels were measured by a RIA method with a sensitivity of 0.5 ng/ml. RESULTS: Results showed any significant differences neither between patients and controls (7.97+/-5.2 ng/ml vs. 7.83+/-3.7 ng/ml) nor between patients with or without Graves' ophthalmopathy (8.29+/-5.0 ng/ml vs. 7.06+/-5.8 ng/ml) (both P>0.05). Moreover, no correlation was found between plasma leptin levels and ophthalmopathy index score, or proptosis. CONCLUSIONS: Although effects of local leptin production in the orbit cannot be excluded, our data suggest that circulating plasma leptin does not have a significant direct influence on ophthalmopathy index score or pathophysiology of Graves' ophthalmopathy.


Assuntos
Doença de Graves/sangue , Leptina/sangue , Adulto , Índice de Massa Corporal , Feminino , Humanos , Masculino
8.
J Clin Rheumatol ; 7(5): 315-21, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17039162

RESUMO

Conflicting data have been published about osteoporosis and bone turnover markers in patients with ankylosing spondylitis (AS). The aim of this study was to determine bone mineral density (BMD) of the lateral lumbar spine in a group of male patients with AS and to investigate the relationship between clinical parameters and markers of bone turnover. Thirty-two consecutive AS patients with a mean disease duration of 14.8 years and 32 control subjects were included. Demographic and clinical characteristics were recorded. The Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) was used to determine the activity of disease. BMD was determined for the lateral lumbar spine in both patients and control groups. Serum osteocalcin and urinary N-telopeptide were measured as bone turnover markers in patient and control groups. Although the mean values of lumbar BMD in AS patients tended to be lower than in the control group, the difference was not statistically significant. Osteoporosis was observed in 11 (34.3%) of AS patients and in 2 (6.2%) of the control group. Osteocalcin levels were significantly higher in AS patients in comparison with control subjects (p < 0.05). In the subgroup analysis according to the activity of the disease, erythrocyte sedimentation rate and N-telopeptide levels were significantly higher in the severely active group when compared with that in mild or moderate disease groups. Active AS patients compared with the control group had significantly lower BMD and significantly higher N-Telopeptide levels (p < 0.05). The levels of BASDAI scores and N-telopeptide values correlated significantly with each other. The incidence of osteoporosis is high in AS patients, and patients with active disease are especially at risk for developing osteoporosis. The monitoring of bone turnover markers and disease activity indices may help to predict patients at risk. Prophylactic and therapeutic strategies are needed to struggle against bone loss in patients with this disabling condition.

9.
Inhal Toxicol ; 12(7): 641-7, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10880149

RESUMO

In this study, acute effects of two different types of cigarette smoking on plasma oxidant/antioxidant status were investigated. For this purpose, malondialdehyde (MDA) levels and antioxidant potential (AOP) values were measured in the plasma samples before and after cigarette smoking at fasting. After the first blood sample was obtained, second and third samples were withdrawn at 1.5 h and 3 h. In the first group, subjects smoked five cigarettes with full flavor (FF), and in the second group, five cigarettes with full-flavor low tar (FFLT). Quality classification is made mainly on the basis of tar content of the products. The cigarette with 23 mg tar is defined as FF and that with 12 mg tar as FFLT. MDA level was found to be significantly increased in the 1.5-h plasma samples of both groups, but the increase was greater in the FF group. AOP values, however, were found to be lower in the 3-h plasma samples of both groups, but the decrease was greater in the FF group compared with the FFLT group. It appears that acute smoking causes oxidant stress in blood plasma once exposed to smoke, and then this effect (MDA) begins to decrease. On the other hand, AOP is lowered due to oxidant stress created by smoke. With regard to the types of cigarettes, the FF product seems to be more oxidant than the FFLT product. Our results suggest that antioxidant supplementation might be beneficial for the smokers to cope with the oxidant load derived from cigarette smoke. It is also clearly seen from these results that cigarette manufacturers should reduce tar/nicotine ratio in their products in order to lessen the toxic effects of smoking without causing increased need to smoke.


Assuntos
Antioxidantes/metabolismo , Oxidantes/sangue , Fumar/sangue , Alcatrões , Adulto , Humanos , Masculino , Malondialdeído/sangue , Alcatrões/análise , Alcatrões/classificação
10.
Diabetes Care ; 23(3): 371-6, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10868868

RESUMO

OBJECTIVE: In advanced stages of diabetic retinopathy, new blood vessels are formed based on undefined mechanisms. Recently, leptin was shown to possess an angiogenic action in vitro and to induce neovascularization in vivo. The aim of the present study was to investigate the relationship between plasma leptin levels and the severity of diabetic retinopathy. RESEARCH DESIGN AND METHODS: There were 70 patients with type 2 diabetes (age 47.9 +/- 9.7 years, BMI 26.4 +/- 3.3 kg/m2) who were seen in a retina outpatient clinic recruited and assigned to subgroups according to the stage of their diabetic retinopathy. There were 66 healthy volunteer subjects matched with the diabetic patients for age, BMI, and sex who served as control subjects (age 46.0 +/- 8.8 years, BMI 27.1 +/- 2.3 kg/m2). Fasting plasma leptin levels were measured. RESULTS: Plasma leptin level of the diabetic patients was not significantly different from the control subjects. In patients with proliferative diabetic retinopathy (n = 17), the mean plasma level of leptin (16.1 +/- 9.2 ng/ml) was significantly higher than that in patients with nonproliferative retinopathy (n = 20) (11.5 +/- 3.5 ng/ml, P = 0.039) or patients without retinopathy (n = 33) (5.8 +/- 3.7 ng/ml, P = 0.001). The mean leptin level in patients with nonproliferative diabetic retinopathy was also significantly higher than that in patients without retinopathy (P = 0.002). CONCLUSIONS: Our results show that the more advanced the diabetic retinopathy, the higher the plasma leptin levels, even after adjusting the leptin levels for BMI. The presence of such a positive correlation need not imply a causal relationship. Nevertheless, previously observed leptin-induced promotion of angiogenesis and neovascularization lends support to the possibility that leptin may play a role in the progression of human diabetic retinopathy to a proliferative phase. This possibility deserves further investigation.


Assuntos
Diabetes Mellitus Tipo 2/fisiopatologia , Retinopatia Diabética/sangue , Leptina/sangue , Biomarcadores/sangue , Glicemia/análise , Pressão Sanguínea , Creatinina/sangue , Diabetes Mellitus Tipo 2/sangue , Retinopatia Diabética/classificação , Feminino , Hemoglobinas Glicadas/análise , Humanos , Masculino , Pessoa de Meia-Idade , Radioimunoensaio , Valores de Referência
11.
Eur J Endocrinol ; 142(2): 170-3, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10664526

RESUMO

BACKGROUND: The obese are usually protected against osteoporosis and have increased bone mineral density and plasma leptin concentrations. A recent in vitro study demonstrated that leptin acts on human marrow stromal cells to enhance differentiation to osteoblasts, suggesting an influence of leptin on bone mass. However, little is known about the relationship between plasma leptin and bone mass in postmenopausal women with osteoporosis. OBJECTIVE: To investigate plasma leptin concentrations in postmenopausal women with osteoporosis to improve the understanding of the role of leptin in determining bone mass. METHODS: Fifty postmenopausal women with osteoporosis (ages 61.18+/-6.51 years; body mass index (BMI) 28. 91+/-3.44kg/m(2), mean+/-s.d.) and 30 age- and BMI-matched healthy postmenopausal women were included in the study. Bone mineral densities (BMD) were measured by dual energy X-ray absorptiometry. Plasma leptin concentrations were determined using an immunoradiometric assay. RESULTS: The median spine BMD value in the patient group (0.695+/-8.26g/cm(2), median+/-s.e.m.) was significantly lower than that in the control group (1.006+/-1. 29g/cm(2), median+/-s.e.m.; z=-7.454, P<0.001). The median plasma leptin concentration in the patient group (18.70+/-1.78ng/ml, median+/-s.e.m.) was not significantly different from that in the control group (22.35+/-2.20ng/ml, median+/-s.e.m.; z=-1.630, P=0. 103). Plasma leptin concentrations were correlated with BMI in both groups (r(s)=0.394, P=0.031 in controls and r(s)=0.404, P=0.004 in the patient group). There was no correlation between plasma leptin concentrations and BMD values in controls (r(s)=-0.107, P=0.575) but a weak correlation was observed in the patient group (r(s)=0.285, P=0.045). CONCLUSION: Our data suggest that circulating plasma leptin does not have a significant direct influence on bone mass in postmenopausal women.


Assuntos
Leptina/sangue , Osteoporose Pós-Menopausa/sangue , Idoso , Densidade Óssea , Feminino , Humanos , Pessoa de Meia-Idade , Concentração Osmolar , Osteoporose Pós-Menopausa/fisiopatologia , Valores de Referência
12.
J Clin Endocrinol Metab ; 85(2): 683-7, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10690876

RESUMO

Previous studies have demonstrated that elevated plasma leptin concentrations are associated with essential hypertension. It has also recently been shown that leptin plays a promoting role in angiogenesis, and the vascular endothelium expresses the long form of leptin receptor. Those data led us to hypothesize that leptin might contribute to end-organ damage in hypertension. Thus, in the present study we evaluated the relationship between plasma leptin concentrations and hypertensive retinopathy (HR). One hundred and eleven patients newly diagnosed with essential hypertension [EHT; mean age, 43.5 +/-10.7 yr; body mass index (BMI), 28.1 +/- 4.4 kg/m2; male/female ratio, 71/40] and 79 healthy normotensive control subjects (NT; mean age, 43.6 +/- 9.2 yr; BMI, 28.2 +/- 3.3 kg/m2; male/female ratio, 50/29) were enrolled in the study. For the assessment of retinopathy according to the Keith-Wagener classification, direct and indirect ophthalmoscopy were performed in all subjects after dilatation of the pupils. Plasma leptin levels were significantly higher in EHT (11.8 +/- 11.1 ng/mL) than in NT (7.2 +/- 5.1 ng/mL) (P = 0.003). Plasma leptin concentrations were strongly correlated with BMI in both EHT (r = 0.45; P = 0.001) and NT (r = 0.38; P = 0.001) groups. Plasma leptin in patients with grade 2 HR (24.8 +/- 15.8 ng/mL; n = 22) was significantly higher than that in patients with grade 1 HR (16.1 +/- 4.9 ng/mL; n = 29; P = 0.001), grade 0 HR (5.1 +/- 3.1 ng/mL; n = 60; P = 0.001), and NT (P = 0.001). Plasma leptin in patients with grade 1 HR was also significantly higher than that in patients without retinopathy (P = 0.001) or in NT (P = 0.001). The estimated threshold of plasma leptin concentration for HR was 10.2 ng/mL. This critical leptin level served largely to separate patients with retinopathy from those without retinopathy. In summary, our results show that plasma leptin concentrations increase progressively with higher grades of hypertensive retinopathy even after correction for BMI, suggesting that a critical leptin level is needed for the development of retinopathy. Elevated concentrations of plasma leptin might be secondary to release of leptin by the vascular endothelium damaged by high blood pressure, as an epiphenomenon. However, a pathogenic role for leptin in hypertensive retinopathy cannot be excluded.


Assuntos
Hipertensão/complicações , Leptina/sangue , Doenças Retinianas/sangue , Doenças Retinianas/etiologia , Adulto , Índice de Massa Corporal , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Oftalmoscopia , Valores de Referência , Doenças Retinianas/patologia
13.
Acta Neurochir (Wien) ; 141(10): 1095-9, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10550656

RESUMO

Hydrocephalus is known to cause various endocrinological abnormalities. These abnormalities are either though a direct effect on anterior hypothalamus or pituitary gland. However almost nothing is known about the effects of hydrocephalus on the intrinsic angiotensin system of the brain. The aim of this study is to investigate the effect of hydrocephalus on neurotransmitter-rich circumventricular organ systems. Such an effect was investigated by means of angiotensin receptor content in subfornical organ (SFO), organum vasculosum lamina terminalis (OVLT), area postrema (AP) and the median eminence (ME). Experimental hydrocephalus was created in rats by the intracisternal kaolin injection method as described by Shapiro et al. The receptor content was measured at 4-6 weeks by in-vitro autoradiography method as described by Israel et al. Angiotensin II receptor content in hydrocephalic animals was found to be statistically increased in SFO, OVLT and ME but not in AP when compared with the normal animals. Receptor content was found to have increased by 182.4% at SFO, 76.7% at ME, 7.7% at AP and 22.1% at OVLT after kaolin injection. These findings may indicate the possible role of CVO's on pathological conditions such as hydrocephalus.


Assuntos
Angiotensina II/análise , Ventrículos Cerebrais/patologia , Hidrocefalia/fisiopatologia , Receptores de Angiotensina/análise , Animais , Autorradiografia , Ventrículos Cerebrais/metabolismo , Modelos Animais de Doenças , Masculino , Ratos
14.
Horm Metab Res ; 31(7): 435-8, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10450836

RESUMO

Previous studies demonstrated elevated plasma leptin and angiotensinogen (PRA) levels in essential hypertension. However, a few studies investigated the relationship between leptin and angiotensinogen levels in both lean and overweight/ obese hypertensives. The aim of the present study was therefore to examine the relationship between blood pressure, leptin and plasma renin activity in normotensives and in both lean and overweight/obese patients with essential hypertension. Two groups of subjects who were carefully matched for age, gender, waist:hip ratio and body mass index (BMI) were studied: 28 normotensives (NT) (age: 40.1+/-9.1 years old, BMI: 28.1+/-3.6 kg/m2, male/female: 18/10) and 33 newly diagnosed mild to moderate essential hypertensives (EHT) (age: 38.9+/-10 years old, BMI: 27.9+/-4.8 kg/m2, male/female: 22/11). No significant differences in age, gender, waist:hip ratio, fasting blood glucose and BMI were detected between EHT and NT groups. However, systolic and diastolic pressures, mean arterial blood pressures, plasma leptin levels and PRA were significantly higher in EHT group than in NT group (P = 0.001). Plasma leptin levels were strongly correlated with BMI in EHT (r=0.67, P = 0.001) and NT groups (r=0.44, P = 0.001). Plasma leptin levels were correlated with plasma PRA levels in both EHT and NT groups (r = 0.66 and r = 0.44; both P < 0.05, respectively). There was no correlation between leptin or PRA and systolic, diastolic pressures, or mean arterial blood pressures. Furthermore, the patients were divided as lean (n=16) and overweight/obese (n = 17) and compared with BMI-matched controls. In both subgroups, plasma leptin and PRA levels were also higher than those of controls. Our results showed that elevated plasma leptin and PRA are associated with hypertension in both lean and overweight/obese hypertensives. Moreover, plasma leptin was significantly correlated with plasma angiotensinogen levels. These findings suggest that adipose mass is an important determinant of blood pressure, although the mechanism is not clear.


Assuntos
Hipertensão/sangue , Proteínas/análise , Renina/sangue , Adulto , Pressão Sanguínea , Índice de Massa Corporal , Feminino , Humanos , Leptina , Masculino , Pessoa de Meia-Idade , Obesidade/sangue
15.
Mem Inst Oswaldo Cruz ; 94(3): 383-6, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10348987

RESUMO

In order to investigate purin and primidin metabolism pathways in hepatitis, adenosine deaminase (ADA) and guanosine deaminase (GDA) activities in sera of patients with different types and manifestations of viral hepatitis disease (A, B, C, D, E, chronic, acute) were investigated and compared with the control group of healthy individuals. Hepatitis cases were classified with respect to their serological findings and clinics. When compared all the hepatitis cases with the controls, levels of aspartate aminotransferase, alanine aminotransferase, and alkaline phosphatase enzymes, as well as ADA and GDA, were significantly higher than the control group (p<0.01). Levels of ADA and GDA in hepatitis cases were determined as 26.07 11.98 IU/l and 2.37 1.91 IU/l, respectively. When compared their ADA and GDA levels amongst the classified hepatitis groups, there was no difference in ADA levels amongst cases (p>0.05). However, GDA levels in hepatitis A group were closed to the controls. Increase in serum ADA activities in hepatitis forms may be dependent on and reflect the increase in phagocytic activity of macrophages and maturation of T-lymphocytes, and may be valuable in monitoring in viral hepatitis cases.


Assuntos
Adenosina Desaminase/metabolismo , Guanosina/metabolismo , Hepatite Viral Humana/sangue , Hepatite Viral Humana/enzimologia , Doença Aguda , Adenosina Desaminase/sangue , Adolescente , Adulto , Alanina Transaminase/sangue , Fosfatase Alcalina/sangue , Aspartato Aminotransferases/sangue , Doença Crônica , Guanosina/sangue , Humanos , Pessoa de Meia-Idade
16.
Int Urol Nephrol ; 31(5): 675-80, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10755359

RESUMO

OBJECTIVE: To examine the usefulness of the ratio of free prostate specific antigen (FPSA) to total prostate specific antigen (TPSA) in men with serum TPSA concentration of 4 to 10 ng/mL by using the cut off value of 0.15 for avoiding unnecessary biopsies. PATIENTS AND METHODS: Two hundred thirty-six men aged between 52 and 91 with symptoms of prostatism were evaluated with digital rectal examination (DRE), FPSA and TPSA measurements. Patients with TPSA values under 4 ng/mL were biopsied if they had positive DRE and/or a FPSA/TPSA ratio lower than 0.15. All patients with TPSA values higher than 4 ng/mL were also biopsied. The predictive value and sensitivity of FPSA/TPSA ratio and TPSA alone were calculated. RESULTS: Eleven patients out of 170 with a TPSA value lower than 4 ng/mL were biopsied. Fifty-five patients had a value between 4.1 and 10 ng/mL. We performed transrectal ultrasound (TRUS) and prostate biopsy in these men except one patient. Biopsy proven prostate cancer was detected only in 12 patients. In this group of patients the predictive value of TPSA was 21%, but the predictive value of FPSA/TPSA ratio of 0.15 was 78% maintaining at least 90% sensitivity. Eleven of the patients had a prostate specific antigen (PSA) value higher than 10 ng/mL. In 6 of these patients the biopsy result was prostate cancer and 10 of these patients had a FPSA/TPSA ratio lower than 0.15. CONCLUSION: In patients with TPSA values between 4-10 ng/mL the cut off value of FPSA/TPSA ratio of 0.15 can be used to eliminate unnecessary biopsies with minimal loss of cancer patients.


Assuntos
Antígeno Prostático Específico/análise , Neoplasias da Próstata/diagnóstico , Idoso , Idoso de 80 Anos ou mais , Humanos , Masculino , Pessoa de Meia-Idade , Antígeno Prostático Específico/sangue , Hiperplasia Prostática/diagnóstico , Sensibilidade e Especificidade
17.
J Endocrinol Invest ; 21(6): 337-41, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9699123

RESUMO

Leptin, the product of the adipose specific ob gene, regulates food intake and energy expenditure. However, little is known about the effects of thyroid status on plasma leptin levels in women. We determined fasting plasma leptin levels before and 1 month after restoration of euthyroidism in 20 female patients with hypothyroidism, 20 female patients with hyperthyroidism and 20 age and BMI-matched female controls. To restore the normal thyroid function patients with hypothyroidism were treated with levothyroxine, whereas patients with hyperthyroidism were treated with propylthiouracil. Plasma leptin levels were measured by a RIA method with a sensitivity of 0.5 microgram/l. Leptin levels were significantly lower in patients with hypothyroidism before treatment (4.17 +/- 2.58 micrograms/l) than in patients with hyperthyroidism (6.80 +/- 4.3 micrograms/l; z = -2.06, p = 0.037). Leptin levels were significantly higher in hyperthyroid patients than in the control group (3.71 +/- 1.69 micrograms/l, z = -2.44, p = 0.014) whereas leptin levels in the hypothyroid patients were not significantly different from those in control subjects (z = -0.16, p = 0.87). Restoration of euthyroid state was not associated with a significant change in leptin levels either in the hypothyroid (from 4.17 +/- 2.58 to 5.22 +/- 3.4 micrograms/l; z = -1.74, p = 0.08) or in the hyperthyroid group (from 6.80 +/- 4.37 micrograms/l to 7.93 +/- 6.25 micrograms/l z = -0.89, p = 0.37), although a tendency for leptin to increase was observed in both groups. There was no correlation between plasma leptin and FT3, FT4, TSH, or BMI either before or after therapy in both groups. Leptin levels were significantly correlated with BMI in the control group (r = -0.53, p = 0.018). We conclude that plasma leptin levels are increased in hyperthyroidism and unchanged in hypothyroidism. Furthermore, our study demonstrates that mean plasma leptin levels are not influenced by short term restoration of euthyroidism in both hypothyroidism and hyperthyroidism, although an effect of long-term treatment may not be excluded.


Assuntos
Hipertireoidismo/sangue , Hipotireoidismo/sangue , Proteínas/metabolismo , Adulto , Índice de Massa Corporal , Jejum , Feminino , Humanos , Hipertireoidismo/tratamento farmacológico , Hipotireoidismo/tratamento farmacológico , Leptina , Propiltiouracila/uso terapêutico , Hormônios Tireóideos/sangue , Tiroxina/uso terapêutico
18.
Horm Metab Res ; 30(5): 266-71, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9660087

RESUMO

Since little is known about the effects of gonadotropin and testosterone treatment on leptin levels in male hypogonadism, we determined fasting plasma leptin levels before and 3 months after treatment in 21 patients with idiopathic hypogonadotropic hypogonadism (IHH), 16 patients with Klinefelter's syndrome and 20 male controls. Patients with IHH were treated with hCG/human menopausal gonadotropin, whereas patients with Klinefelter's syndrome received T treatment. Plasma leptin levels were measured by an RIA with a sensitivity of 0.5 microg/L. Mean leptin levels in patients with IHH before treatment (9.23+/-4.09 microg/L) were not significantly different from those in patients with Klinefelter's syndrome (7.29+/-5.05 microg/L; z=-1.41; P=0.15). Leptin levels in both IHH and Klinefelter's syndrome groups were, however, significantly higher than in the normal men (3.91+/-1.67 microg/L) (P<0.001 and P<0.01, respectively). Mean leptin levels did not change significantly 3 months after the initiation of gonadotropin (11.6+/-6.44 microg/L) or T (8.32+/-5.17 microg/L) treatment in either IHH or Klinefelter's syndrome. Our study demonstrated that mean plasma leptin levels are not influenced by short-term gonadotropin or T treatment in male hypogonadism.


Assuntos
Gonadotropina Coriônica/administração & dosagem , Síndrome de Klinefelter/tratamento farmacológico , Síndrome de Klinefelter/metabolismo , Proteínas/metabolismo , Testosterona/administração & dosagem , Adulto , Hormônio Foliculoestimulante/sangue , Humanos , Leptina , Hormônio Luteinizante/sangue , Masculino , Prolactina/sangue , Testículo/patologia
19.
J Clin Endocrinol Metab ; 81(5): 1877-81, 1996 May.
Artigo em Inglês | MEDLINE | ID: mdl-8626851

RESUMO

It has previously been shown that increased nocturnal melatonin (MT) secretion exists in male patients with hypogonadotropic hypogonadism. However, little is known about the effects of gonadotropin and testosterone (T) treatment on early morning plasma MT levels in male hypogonadism. Also, the impact of gonadal steroids on plasma MT levels is an open question. We, therefore, determined early morning plasma MT levels at the same hour before and 3 months after treatment in 21 patients with idiopathic hypogonadotropic hypogonadism (IHH), 10 patients with primary hypogonadism, and 11 male controls. Plasma FSH, LH, PRL, T, and estradiol levels were also determined before and 3 months after treatment. Patients with IHH were treated with hCG/human menopausal gonadotropin, whereas patients with primary hypogonadism received T treatment. Short term treatments did not achieve normal T levels, although significant increases in T were observed in both groups. Plasma MT levels were measured by a RIA with a sensitivity of 10.7 pmol/L. Mean plasma MT levels before treatment were significantly higher in IHH (41.8 +/- 24.4 pmol/L) compared with those in the controls (21.7 +/- 10.8 pmol/L; P < 0.05). However, a slight, but not significant, increase in MT (34.2 +/- 21.1 pmol/L) was found in primary hypogonadism. Mean MT levels did not change significantly 3 months after the initiation of gonadotropin (41.7 +/- 22.8 pmol/L) or T (28.4 +/- 12.6 pmol/L) treatment in either IHH or primary hypogonadism, although a tendency for MT to decrease was observed in both groups. No correlation was found between MT and circulating FSH, LH, PRL, and gonadal steroids either before or after therapy. We conclude that male patients with IHH have increased early morning MT levels, although the pathophysiological mechanism is not clear. Furthermore, our study demonstrated that mean plasma MT levels are not influenced by short term gonadotropin or T treatment in male hypogonadism, although a longer time effect of gonadotropins or T treatment may not be excluded. The lack of correlation between plasma MT and circulating gonadal steroids before and after treatment suggests that there is no classic feedback regulation between the pineal gland and the testes.


Assuntos
Ritmo Circadiano , Hipogonadismo/sangue , Melatonina/sangue , Adulto , Gonadotropina Coriônica/uso terapêutico , Desidroepiandrosterona/análogos & derivados , Desidroepiandrosterona/sangue , Sulfato de Desidroepiandrosterona , Estradiol/sangue , Hormônio Foliculoestimulante/sangue , Humanos , Hipogonadismo/tratamento farmacológico , Hipogonadismo/patologia , Hormônio Luteinizante/sangue , Masculino , Menotropinas/uso terapêutico , Prolactina/sangue , Globulina de Ligação a Hormônio Sexual/metabolismo , Testículo/patologia
20.
Int Urol Nephrol ; 28(3): 309-13, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8899469

RESUMO

To evaluate the early and late effects of extracorporeal shock wave lithotripsy on renal function, we prospectively designed a controlled study using a Direx lithotriptor. Twenty-five patients with renal stones and 16 healthy volunteers as the control group were included in the study. Blood and urine samples were collected before and after 24 hours, seven days and 8 months in the patient group. White blood cell count, serum levels of haemoglobin, urea, creatinine, SGOT, SGPT, AP, and LDH were determined. 24-hour urine specimens were collected to be tested for volume, excretion of creatinine, albumin, N-acetyl-beta-glucosaminidase, gamma-glutamyltransferase and beta-2-microglobulin. There were statistically significant increments in the secretion of urinary enzymes and albumin in the early period after ESWL, no longer lasting 8 months after the procedure. At 8 months one patient was hypertensive as judged by the diastolic pressure above 95 mm Hg. The results of this study showed that, although there was a transient glomerular and tubular damage after extracorporeal shock wave lithotripsy, the procedure seems safe and causes no permanent deterioration in renal function.


Assuntos
Cálculos Renais/fisiopatologia , Cálculos Renais/cirurgia , Glomérulos Renais/fisiopatologia , Túbulos Renais/fisiopatologia , Litotripsia , Adulto , Feminino , Humanos , Cálculos Renais/metabolismo , Testes de Função Renal , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...