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991.
Franco C Andersson B Lönn L Bengtsson BA Svensson J Johannsson G 《The Journal of clinical endocrinology and metabolism》2007,92(7):2644-2647
CONTEXT: Abdominal obesity is associated with low GH secretion, elevated circulating markers of inflammation, and increased risk of cardiovascular disease. OBJECTIVE: The objective was to study the effect of GH treatment on inflammatory markers and vascular adhesion molecules in postmenopausal women with abdominal obesity. DESIGN: Forty women aged 51-63 yr received GH (0.67 mg/d) in a randomized, double-blind, placebo-controlled, 12-month trial. Measurements of inflammatory markers [highly sensitive C-reactive protein (CRP), IL-6, and amyloid polypeptideA] and markers of endothelial dysfunction (soluble E-selectin, vascular adhesion molecule-1, intercellular molecule-1, and matrix metalloproteinase-9) were performed at baseline and after 6 and 12 months of treatment. RESULTS: After 12 months, the mean IGF sd score was 0.9 +/- 1.5 and -0.8 +/- 0.6 in the GH and placebo groups, respectively. GH treatment reduced CRP and IL-6 levels compared with placebo (P = 0.03 and P = 0.05, respectively), whereas the markers of endothelial dysfunction were unaffected. Within the GH-treated group, a reduction was shown in CRP (4.3 +/- 4 to 3.0 +/- 3 mg/liter; P < 0.05) and in IL-6 (4.4 +/- 2 to 3.3 +/- 2 ng/liter; P < 0.01). In the GH-treated group, the decrease in CRP and IL-6 correlated with a reduction in visceral adipose tissue (r = 0.7, P < 0.001 and r = 0.5, P < 0.05, respectively). CONCLUSION: GH treatment in postmenopausal women with abdominal obesity reduced serum markers of systemic inflammation. Circulating markers of endothelial dysfunction were unaffected by treatment. 相似文献
992.
Palming J Sjöholm K Jernås M Lystig TC Gummesson A Romeo S Lönn L Lönn M Carlsson B Carlsson LM 《The Journal of clinical endocrinology and metabolism》2007,92(6):2346-2352
CONTEXT: We have previously identified nicotinamide adenine dinucleotide phosphate:quinone oxidoreductase 1 (NQO1), an enzyme involved in the protection against oxidative stress, as a gene predominantly expressed in human adipocytes. Studies in mice deficient in NQO1 activity suggest that NQO1 may also play an important role in metabolism. OBJECTIVE: The aim of this study was to explore the expression and regulation of NQO1 in human adipose tissue (AT) and isolated adipocytes. PATIENTS AND RESULTS: The high expression of NQO1 in adipocytes was verified in human adipocytes and AT by real-time PCR. DNA microarray analysis showed that NQO1 was expressed at higher levels in large compared with small adipocytes, isolated from the same fat biopsy. Furthermore, NQO1 mRNA levels were positively correlated with adipocyte size (n = 7; P < 0.002). During an 18-wk diet regime (n = 24; mean weight loss 27 kg), the NQO1 expression in human sc AT was down-regulated (P < 0.0001), and mRNA levels correlated with body mass index (P = 0.0005), sc, and total abdominal AT areas, as determined by computerized tomography (P < 0.0001, both) and metabolic parameters. NQO1 mRNA levels were also positively correlated with aspartate aminotransferase (P = 0.0028) and alanine aminotransferase (P = 0.0219), markers known to be associated with severity of hepatic steatosis. CONCLUSIONS: NQO1 is highly expressed in human AT, particularly in large adipocytes. AT NQO1 expression is reduced during diet-induced weight loss, and the expression levels positively correlate with adiposity, glucose tolerance, and markers of liver dysfunction. Together, these findings indicate a role for NQO1 in the metabolic complications of human obesity. 相似文献
993.
We aimed to study trends in gender-related differences in incidence, and prevalence for long-term oxygen therapy due to chronic obstructive pulmonary disease. Another aim was to study survival after onset of oxygen therapy. Prospectively followed were 5689 Swedish patients, who were prescribed oxygen therapy because of chronic obstructive pulmonary disease from 1987 to 2000. The annual incidence of women starting oxygen therapy increased more rapidly than that in men. In 2000, 7.6 per 100,000 women started treatment compared with 7.1 in men. The frequency of ever smoking in Sweden in the age group receiving oxygen, i.e. age 65-84 years, was 36.4% in women and 65.0% in men, indicating that women ran a higher risk of developing an oxygen-requiring chronic hypoxaemia. An increase in women requiring oxygen therapy is predicted due to the increase in smoking frequency in young and middle-aged women and it is estimated that about 70% of Swedish patients on oxygen in 2026 will be women, with an estimated prevalence of 61 per 100,000. In conclusion, the incidence and prevalence for long-term oxygen therapy increases more rapidly among women than in men. This is probably due to the increased frequency of smoking in women compared with men and a higher susceptibility to develop severe hypoxaemia in women. The survival is better in women with long-term oxygen therapy than in men. 相似文献
994.
Mathiassen ON Buus NH Sihm I Thybo NK Mørn B Schroeder AP Thygesen K Aalkjaer C Lederballe O Mulvany MJ Christensen KL 《Journal of hypertension》2007,25(5):1021-1026
OBJECTIVE: Structural abnormality of resistance arteries is a characteristic pathophysiological phenomenon in essential hypertension and can be assessed in vitro as an increase in the media: lumen ratio (M: L) of isolated small arteries. We have investigated whether M: L is a risk predictor in uncomplicated essential hypertensive patients. Recently, high M: L was demonstrated as a prognostic marker in patients at high cardiovascular risk, including normotensive type 2 diabetic patients. Since diabetes is associated with pressure-independent changes in M: L, the relevance of this finding to essential hypertension has been uncertain. METHODS: We conducted a follow-up survey of 159 essential hypertensive patients, who had previously been submitted to a M: L evaluation while participating in a clinical trial. They composed a homogeneous moderate-risk group, with no concomitant diseases, and represented 1661 years of follow-up. RESULTS: Thirty patients suffered a documented predefined cardiovascular event during follow-up. Increased relative risk (RR) was associated with M: L >or= 0.083 (mean level of the hypertensive cohort), RR = 2.34 [95% confidence interval (CI) 1.11-4.95], and with M: L >or= 0.098 (mean level of a normotensive control group + 2SD), RR = 2.49 (95% CI 1.21-5.11). Both results remained significant (RR = 2.19, 95% CI 1.04-4.64, and RR = 2.20, 95% CI 1.06-4.56, respectively) when adjusted for Heart Score level (10-year mortality risk-estimate, integrating age, gender, systolic blood pressure, cholesterol and smoking). CONCLUSION: Abnormal resistance artery structure independently predicts cardiovascular events in essential hypertensive patients at moderate risk. 相似文献
995.
Andersen O Pedersen SB Svenstrup B Hansen BR Paulsen SK Rathje GS Richelsen B Nielsen JO Madsbad S Iversen J Haugaard SB 《Clinical endocrinology》2007,67(2):250-258
OBJECTIVE: Circulating oestradiol and testosterone, which have been shown to increase in human immunodeficiency virus (HIV)-infected patients following highly active antiretroviral therapy (HAART), may influence fat distribution and insulin sensitivity. Oestradiol increases subcutaneous adipose tissue in humans possibly through binding to oestrogen-receptor-alpha, which in turn activates anti-lipolytic alpha2A-adrenergic-receptor. DESIGN AND METHODS: To address these issues circulating pituitary-gonadal-axis hormones and gene expression of receptors in subcutaneous adipose tissue were determined in 31 nondiabetic HIV-infected male patients receiving HAART (16 with lipodystrophy), in whom measures of fat distribution (CT and DEXA-scans) and insulin sensitivity (hyperinsulinaemic euglycaemic clamp) were available. RESULTS: Total and free oestradiol and testosterone were decreased in lipodystrophic patients compared to nonlipodystrophic patients, whereas luteinizing hormone, follicle-stimulating hormone and prolactin were similar and normal in both study groups. Ratio of subcutaneous to total abdominal fat mass, limb fat, and insulin sensitivity, which were all decreased in lipodystrophic patients, correlated positively with both plasma oestradiol and testosterone (n = 31). Glycerol concentration during clamp (a marker of lipolysis) correlated inversely with expression of alpha2A-adrenergic-receptor, ratio of subcutaneous to total abdominal fat mass, and limb fat, respectively. Expression of alpha2A-adrenergic-receptor correlated positively with expression of oestrogen-receptor-alpha. CONCLUSIONS: The results fit the hypothesis that sex hormones play a role in altered fat distribution and insulin sensitivity of male patients with HIV-lipodystrophy. The effect of oestradiol on the subcutaneous fat depot and lipolysis may be mediated in part through binding to the oestrogen-receptor-alpha, in turn activating anti-lipolytic alpha2A-adrenergic-receptor. 相似文献
996.
Behre CJ Gummesson A Jernås M Lystig TC Fagerberg B Carlsson B Carlsson LM 《Metabolism: clinical and experimental》2007,56(8):1022-1028
997.
The duration of breastfeeding has attracted much interest, as a prolonged period of breastfeeding has been shown to reduce the risk of developing obesity. The mechanism behind the reduced risk is, however, poorly understood. The novel hormone ghrelin augments appetite, promotes body weight increase and increases adiposity. The majority of circulating ghrelin emanates from endocrine cells in the oxyntic mucosa of the stomach. In newborn humans and rodents, the number of ghrelin cells is low after birth until weaning, when the cell population is greatly expanded. To date, information about the influence of weaning perturbations on ghrelin cell development is scarce. Therefore, we studied the effect of delayed weaning on gastric ghrelin expression and plasma ghrelin concentration. To this end, special food separator cages were used to prevent the pups from eating solid food, forcing them to drink milk up to 21 days of age. Gastric ghrelin expression was examined by immunocytochemistry and in situ hybridisation, and plasma concentrations were assessed by RIA. Our data showed that gastric ghrelin expression and plasma ghrelin concentration are maintained at a lower level by delayed weaning. We also found that the relation between gastric ghrelin expression and body weight was altered by delayed weaning. Thus, control rats displayed a positive correlation between ghrelin expression and body weight, while no such correlation was evident in animals with delayed weaning. We conclude that delayed weaning exerts a negative influence on ghrelin expression, and that the onset of solid food intake may trigger normal ghrelin expression. Therefore, we suggest that ghrelin may constitute a hormonal link between the duration of breastfeeding and body weight development. 相似文献
998.
999.
Profiling of diffuse large B-cell lymphoma by immunohistochemistry: identification of prognostic subgroups 总被引:1,自引:0,他引:1
Sjö LD Poulsen CB Hansen M Møller MB Ralfkiaer E 《European journal of haematology》2007,79(6):501-507
Diffuse large B-cell lymphoma (DLBCL) is a frequent lymphoma subtype with a heterogeneous behavior and a variable response to conventional chemotherapy. This clinical diversity is believed to reflect differences in the molecular pathways leading to lymphomagenesis. In this study, we have analyzed pretreatment, diagnostic samples from 108 DLBCL by immunohistology for expression of four markers linked to germinal center B-cells (CD10, Bcl-6), postgerminal center B-cells (MUM1) and apoptosis (Bcl-2). The results indicate that both CD10 and Bcl-6 are favorable prognostic indicators, in contrast to Bcl-2, which is an adverse parameter. Furthermore, using two algorithms for distinction between low- and high-risk patients proposed by Hans et al. (Blood, 2004; 103:275) and Muris et al. (Journal of Pathology, 2006; 208:714), it is shown that both are useful for predicting outcome in DLBCL. However, in this report, the algorithm of Hans et al. was superior to that of Muris et al. These findings confirm and extend other studies and indicate that different prognostic subgroups of DLBCL can be distinguished by simple immunohistological investigations for a limited number of markers. Whether these groups are also relevant for individual treatment decisions will be important to investigate in prospective studies. 相似文献
1000.
Lp(a) lipoprotein and plasminogen activity in patients with different etiology of ischemic stroke 总被引:3,自引:0,他引:3
Petersen NH Schmied AB Zeller JA Plendl H Deuschl G Zunker P 《Cerebrovascular diseases (Basel, Switzerland)》2007,23(2-3):188-193
BACKGROUND AND PURPOSE: Lp(a) lipoprotein plays an important part in atherothrombogenesis and is considered an independent risk factor for coronary heart disease. However, its role in cerebrovascular disease remains unclear, in particular because of the heterogeneous nature of strokes. We investigated whether elevated Lp(a) is more frequent in ischemic stroke related to atherothrombosis than in other etiologies of stroke. Because of the close structural homology between Lp(a) and plasminogen, we also studied the role of plasminogen in different stroke subtypes and whether there is a dependency on Lp(a) plasma levels. METHODS: Lp(a) levels and plasminogen activity were measured in 253 consecutive patients with acute ischemic stroke and in 63 controls (CS). Subtypes of stroke were established according to the TOAST criteria. RESULTS: Median Lp(a) levels were found to be higher in the total cerebral infarction group and in patients with large artery atherosclerosis (LAA) when compared with CS (20.9 and 22.0 mg/dl, respectively, vs. 16.0 mg/dl; p < 0.05). In addition, elevated Lp(a) levels >30 mg/dl were more frequent among the LAA subgroup than among CS (39.4 vs. 11.1%; p < 0.001). Mean plasminogen activity was lower in the total cerebral infarction group (110.8 vs. 120.3%; p < 0.001) and in patients with cardioembolic stroke (109.8 vs. 120.3%; p < 0.05) when compared with CS. There was no correlation between Lp(a) levels and plasminogen activity. CONCLUSIONS: Our results support the hypothesis that elevated Lp(a) is a risk factor for ischemic stroke and especially for strokes caused by LAA. Low plasminogen activity may play a role in the pathogenesis of cerebrovascular disease, especially for the development of cardioembolic stroke. 相似文献