Cardiovascular risk factors in men: The role of gonadal steroids and sex hormone-binding globulin

Males have higher risk of cardiovascular disease (CVD) than premenopausal females. Gonadal steroids are probably involved in the gender difference in CVD, but previous results have been conflicting. We investigated the associations between CVD risk factors and sex hormones in a cross-sectional designed study of 508 healthy males, aged 41 to 72 years. We determined total testosterone (T), sex hormone-binding globulin (SHBG), free androgen index (FAI), and estradiol (E2) and studied their relationship to body fat mass (BF), blood pressure (BP), aortic compliance, left ventricular mass (LVM), and plasma lipids (total cholesterol, high-density lipoprotein [HDL], low-density lipoprotein [LDL], very--low-density lipoprotein [VLDL], and triglycerides). In quartile analyses after adjustment for confounders (age, body mass index [BMI], alcohol consumption, and smoking), SHBG and E2 were positively associated with HDL, while FAI was negatively associated with HDL. T and SHBG were negatively associated with VLDL and triglycerides, while FAI was positively associated with VLDL and triglycerides. T and SHBG were negatively associated with BMI and BF, while FAI and E2 were positively associated with BMI and BF. E2 was negatively associated with LVM. No hormone varied with total cholesterol, LDL, BP, and aortic compliance in the adjusted analyses. In multiple regression analyses, SHBG was the main predictive variable of HDL, VLDL, and triglycerides explaining 12%, 17%, and 17% of the variation, respectively. No other hormones were selected as predictive variables for VLDL and triglycerides, but E2, T, and FAI were selected in the HDL regression, explaining 3%, 2%, and less than 1%, respectively. Our regression analyses illustrate the diverging results when investigating associations between gonadal steroids and lipids with and without SHBG adjustment. Atherogenic lipid profile in males is associated with low SHBG, low T levels, and a high FAI. Males with high E2 levels may have a less atherogenic lipid profile and lower LVM. SHBG is a key hormone in the association between sex hormones and plasma lipids. We suggest that conflicting results of cross-sectional and intervention studies of sex hormones and lipids, in part, may be explained by interindividual differences or changes in SHBG. Thus, further studies on the potential role of SHBG in the development of ischemic heart disease (IHD) should be performed.     

Regional differences in expression of specific markers for human embryonic stem cells

Characterization of human embryonic stem cell (hESC) lines derived from the inner cell masses of blastocysts generally includes expression analysis of markers such as OCT4, NANOG, SSEA3, SSEA4, TRA-1-60 and TRA-1-81. Expression is usually detected by immunocytochemical staining of entire colonies of hESC, using one colony for each individual marker. Four newly established hESC lines showed the expected expression pattern and were capable of differentiating into the three germ layers in vitro. Neighbouring sections of entire colonies grown for 4, 11, 21 and 28 days respectively were stained with different markers to study the regional distribution and cellular co-expression. TRA-1-60 staining defined the hESC territory at all time points analysed. This territory comprised a characteristic OCT4 and NANOG staining often in overlapping subregions. Staining intensity of nuclei varied from strong OCT4 staining to weak or absent NANOG staining, and vice versa. SSEA4 staining was only observed in small clusters or single cells and not confined to the TRA territory. Co-expression of all markers was only detected in small areas. SSEA1 expression was found exclusively outside the TRA territory. In conclusion, pronounced regional differences in the expression of markers considered specific for undifferentiated hESC may suggest the existence of different cell populations.     

hace1 Influences zebrafish cardiac development via ROS‐dependent mechanisms

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Narcolepsy and pregnancy: a retrospective European evaluation of 249 pregnancies

In a retrospective cohort study undertaken in 12 European countries, 249 female narcoleptic patients with cataplexy (n = 216) and without cataplexy (n = 33) completed a self‐administrated questionnaire regarding pregnancy and childbirth. The cohort was divided further into patients whose symptoms of narcolepsy started before or during pregnancy (308 pregnancies) and those in whom the first symptoms of narcolepsy appeared after delivery (106 pregnancies). Patients with narcolepsy during pregnancy were older during their first pregnancy (P < 0.001) and had a higher body mass index (BMI) prior to pregnancy (P < 0.01). Weight gain during pregnancy was higher in narcoleptic patients with cataplexy (P < 0.01). More patients with narcolepsy–cataplexy during pregnancy had impaired glucose metabolism and anaemia. Three patients experienced cataplexy during delivery. The rate of caesarean sections was higher in the narcolepsy–cataplexy group compared to the narcolepsy group (P < 0.05). The mean birth weight and gestational age of neonates were within the normal range and did not differ across groups. Neonatal care was affected adversely by symptoms of narcolepsy in 60.1% of those with narcolepsy during pregnancy. This study reports more obstetric complications in patients with narcolepsy–cataplexy during pregnancy; however, these were not severe. This group also had a higher BMI and higher incidence of impaired glucose metabolism during pregnancy. Caesarian section was conducted more frequently in narcolepsy–cataplexy patients, despite cataplexy being a rare event during delivery. Furthermore, symptoms of narcolepsy may render care of the infant more difficult.     

Identification of the mononuclear cell infiltrate in the superior cervical ganglion of athymic nude and euthymic rats after guanethidine-induced sympathectomy

Guanethidine sulphate 40 mg/kg intraperitoneally for 14 days induced chromatolysis and nerve cell death in the superior cervical ganglia of athymic nude (rnu/rnu) LEW/Mol rats and their euthymic (+/rnu) LEW/Mol heterozygous littermates. Histologically the sympathetic ganglia were dominated by an infiltration of small inflammatory cells. By means of monoclonal antibodies these cells were identified. The number of B-lymphocytes increased following guanethidine in both athymic and euthymic rats. The number of T-lymphocytes increased to a great extent in euthymic rats, but was virtually missing in athymic rats. The number of NK-cells and monocytes/macrophages increased in both athymic and euthymic rats. The conclusion is, that guanethidine exerts a direct effect on sympathetic ganglion cells followed by a thymus-independent immune response.     

Ein Fall von Transpositio aortae et a. pulmonalis (Typus IIIb Spitzer)

Ohne ZusammenfassungMit 5 Textabbildung.