Effect of the amount of body fat on the age-associated increase in serum cholesterol

This study investigates the contribution of body fat stores on the age-associated increase in serum cholesterol and triglyceride levels. Percentage of body fat was measured by hydrostatic weighing, and serum cholesterol, triglyceride, low-density lipoprotein cholesterol, and high-density lipoprotein cholesterol levels were determined in a sample of 472 healthy men and women ages 18-50 years. In both sexes, body fat mass was significantly correlated with serum cholesterol (r = 0.21 in men and r = 0.24 in women, P less than 0.01) and triglyceride (r = 0.33 in men and r = 0.24 in women, P less than 0.01) levels. After adjustment for the association between age and serum cholesterol, no correlation was observed between body fat mass and serum cholesterol (r = 0.01 in men and r = 0.09 in women). After correction for age, serum triglyceride levels remained significantly correlated with body fat mass (r = 0.26 and r = 0.17 in men and women, respectively, P less than 0.05). As body fat also increases with age, the possibility that a partial correlation coefficient procedure eliminated a portion of the age effect mediated by an age-related increase in fat, was addressed by performing further analyses. Within each sex subsample two sets of analyses were performed on (a) three groups of subjects individually paired for age but with different levels of body fat stores, and (b) three groups of subjects paired for the amount of body fat but differing in age.(ABSTRACT TRUNCATED AT 250 WORDS)     

Erythropoietin and oxidative stress in haemodialysis: beneficial effects of vitamin E supplementation

Oxidative stress can produce profound alterations to cellular membrane lipids, impairing cell metabolism and viability. This phenomenon, previously observed in haemodialysis patients, had been proposed as a significant factor in regard to haemodialysis-related shortened red blood cells (RBC) survival. In the present study, several parameters associated with oxidative stress were evaluated in a group of haemodialysis patients either receiving erythropoietin therapy (n=12, mean erythropoietin dose 88±24 U/kg/week) or not receiving such therapy (n=20), and in 38 controls. Malonyldialdehyde (MDA, nmol/ml), an end-product of lipid peroxidation, and RBC anti-oxidant systems were measured, including RBC &agr;-tocopherol (RBC vitamin E, mg/l), RBC glutathione (GSH, nmol/mgHb), and RBC superoxide dismutase activity (SOD, U/mgHb). Plasma vitamin E concentrations were also evaluated. Finally, oral vitamin E supplementation (500 mg daily), an exogenous antioxidant, was administered for 6 months to seven patients from the dialysis group receiving erythropoietin while oxidative parameters were repeatedly evaluated and erythropoietin requirements monitored, in order to appreciate the therapeutic relevance of an antioxidant supplementation. An elevation of serum MDA was observed in all haemodialysis patients and a significant decrease in RBC vitamin E, despite normal serum vitamin E levels. Furthermore, the reduction in RBC vitamin E was more important in patients treated with erythropoietin. Vitamin E supplementation resulted in a significant increase in RBC vitamin E (from 0.3±0.1 to 1.2±0.2 mg/l of pellet) and a reduction in erythropoietin dose (from 93±24 to 74±26 U/kg/week) while maintaining stable haemoglobin concentrations. These results suggest that the oxidative stress could be one of the resistance factors to erythropoietin response in haemodialysis and that vitamin E supplementation could have a sparing effect on erythropoietin dosage requirement. Key words: antioxidant; erythropoietin; haemodiafiltration; lipid peroxidation; oxidative stress; vitamin E      

The involvement of the sympathetic nervous system in meal-induced thermogenesis in mice.

The acute effect of food intake on the activity of the sympathetic nervous system (SNS) in both heart and brown adipose tissue (BAT) was investigated in mice. Upon delivery to the laboratory mice were housed singly and divided into two groups. Half the mice were accustomed to eat their daily food ration in two meals whereas the other half were given continuous access to food. SNS activity in both heart and BAT was estimated by measuring the accumulation of dopamine (DA) after having blocked the transformation of dopamine into noradrenaline (NA) with 1-cyclohexyl-2-mercapto-imidazole (CHMI). CHMI inhibits the enzyme dopamine beta-hydroxylase. On the day SNS activity was assessed, continuously fed (CF) or meal-fed (MF) mice were injected with either saline or CHMI one hour before being killed. In order to assess the anticipatory effects of being fed, a group of mice already accustomed to the meal-feeding schedule were not allowed to eat after the injections. Additional CF and MF mice were killed without being injected in order to determine the basal levels of both DA and NA. The results show that the accumulation of DA in both heart and BAT was higher in MF than CF mice regardless of whether MF mice were or were not fed after the injection of CHMI. It therefore appears that the intake of food may increase SNS activity in various tissues in mice, and that such a response may be largely of cephalic origin.     

A framework for evaluating image segmentation algorithms.

The purpose of this paper is to describe a framework for evaluating image segmentation algorithms. Image segmentation consists of object recognition and delineation. For evaluating segmentation methods, three factors-precision (reliability), accuracy (validity), and efficiency (viability)-need to be considered for both recognition and delineation. To assess precision, we need to choose a figure of merit, repeat segmentation considering all sources of variation, and determine variations in figure of merit via statistical analysis. It is impossible usually to establish true segmentation. Hence, to assess accuracy, we need to choose a surrogate of true segmentation and proceed as for precision. In determining accuracy, it may be important to consider different 'landmark' areas of the structure to be segmented depending on the application. To assess efficiency, both the computational and the user time required for algorithm training and for algorithm execution should be measured and analyzed. Precision, accuracy, and efficiency factors have an influence on one another. It is difficult to improve one factor without affecting others. Segmentation methods must be compared based on all three factors, as illustrated in an example wherein two methods are compared in a particular application domain. The weight given to each factor depends on application.     

Disseminated lupus erythematosus in children: guidelines about investigations during the initial evaluation and follow-up]

Childhood-onset systemic lupus erythematosus (SLE) is often severe and has a serious long-term morbidity. Pediatric guidelines about its management do not exist. The French study group of childhood-onset SLE proposes recommendations about the investigation which are needed at diagnosis and during follow-up of SLE, in order to adjust the treatment according to the severity of the disease and to avoid unnecessary investigations.     

Prévalence d''Aeromonas spp. dans les gastro-entérites de l''enfant.

A selective medium and biochemical tests were used to search for Aeromonas spp. in the stools of 536 children, more than 90% of whom had "gastroenteritis", seen at Sainte-Justine Hospital, Montreal, in June or July 1986. The organism was found in seven children, six of whom had bloody diarrhea. One of the six, a 6 1/2-year-old boy, required intravenous alimentation and later manifested ulcerative colitis; the other five recovered. The remaining child, a 14-year-old boy, had synovitis of the knee and spondylarthritis. Two of the seven carried other enteric pathogens. The authors discuss the pathogenicity of Aeromonas spp., which is not very marked in temperate climates, in human summer diarrhea and its possible role in the development of ulcerative colitis.     

Expression of cadherins and CD44 isoforms in ovarian endometrial cysts

We evaluated the immunohistochemical expression of cadherins and CD44 variants in 20 endometriomas, 20 cystadenomas, 20 borderline ovarian tumours as well as 20 ovarian carcinomas, and the serological and cystic fluid concentrations of soluble E-cadherin and soluble CD44 standard (sCD44sdt) in 20 endometriomas, 20 cystadenomas, six borderline and 11 carcinomas of the ovary. In endometriomas, immunostaining of E- and N-cadherin was negative (20 and 30% respectively). CD44 H, v3 and v6 immunostaining were detected in 63, 10 and 40% respectively. A difference in immunostaining for E-cadherin was found between endometriomas and cystadenomas (P < 0.001) and for N- cadherin between endometriomas and carcinomas (P < 0.001). A difference in CD44H immunostaining was observed between endometriomas and cystadenomas (P < 0.035) but not with borderline ovarian tumours and carcinomas. No difference in serum concentrations of soluble E- cadherins and CD44 standard was found between the four groups of tumours. Cystic fluid concentrations of E-cadherin were lower in endometriomas than in borderline tumours and ovarian carcinomas (P < 0.001). High concentrations of soluble CD44 standard cystic fluid were found in endometriomas than in other ovarian cysts. Endometriomas and borderline tumours share alterations of cadherins and CD44 isoforms which may help in the understanding of the aggressive and invasive potentials of endometriotic cells.      

Conservative treatment in epithelial ovarian cancer: results of a multicentre study of the GCCLCC (Groupe des Chirurgiens de Centre de Lutte Contre le Cancer) and SFOG (Société Francaise d'Oncologie Gynécologique)

BACKGROUND: Results of conservative management of epithelial ovarian cancer (EOC) remain controversial in the literature. The aim of this study was to assess the clinical outcomes and fertility following fertility-sparing surgical management of EOC in a retrospective multicentre study. METHODS: A multicentre retrospective study was performed by members of two French groups. Six inclusion criteria were defined: (i) Histological review by the same pathologist; (ii) age < or =40 years; (iii) conservative management; (iv) complete peritoneal staging; (v) delivery of a platinum-based chemotherapy in stage > or = IC; and (vi) follow-up >1 year. RESULTS: Thirty-four patients fulfilled the inclusion criteria: 30 had stage IA disease; three had stage IC and one had stage IIA. Eleven patients had recurrence: 10 patients had invasive disease and one had borderline recurrence. Among 10 patients with invasive recurrence, initial stage and grade were: stage IA G1, n = 1; stage IA G2, n = 4; stage IA G3, n = 1; and stage> or = IC, n = 4. All patients with stage > IA had recurrence. Ten pregnancies were observed in nine patients. CONCLUSION: Conservative surgery for patients with EOC could be considered in young patients with stage IA G1 disease. This procedure should not be performed in patients with FIGO stage > IA.