a1_Chronic smoking alters the circulating levels of sex hormones and possibly also the neuroactive steroids. However, the data available is limited. Therefore, a broad spectrum of free and conjugated steroids and related substances was quantified by GC-MS and RIA in premenopausal smokers and in age-matched (38.9±7.3 years of age) non-smokers in the follicular (FP) and luteal phases (LP) of menstrual cycle (10 non-smokers and 10 smokers, in the FP, and 10 non-smokers and 8 smokers in the LP). Smokers in both phases of the menstrual cycle showed higher levels of conjugated 17-hydroxypregnenolone, 5α-dihydroprogesterone, conjugated isopregnanolone, conjugated 5α-pregnane-3β,20α-diol, conjugated androstenediol, androstenedione, testosterone, free testosterone, conjugated 5α-androstane-3α/β,17β-diols, and higher free testosterone index. In the FP, the smokers exhibited higher levels of conjugated pregnenolone, progesterone, conjugated pregnanolone, lutropin, and a higher lutropin/follitropin ratio, but lower levels of cortisol, allopregnanolone, and pregnanolone. In the LP, the smokers exhibited higher levels of free and conjugated 20α-dihydropregnenolone, free and conjugated dehydroepiandrosterone, free androstenediol, 5α-dihydrotestosterone, free and conjugated androsterone, free and conjugated epiandrosterone, free and conjugated etiocholanolone, 7α/β-hydroxy-dehydroepiandrosterone isomers, and follitropin but lower levels of estradiol and sex hormone binding globulin (SHBG) and lower values of the lutropin/follitropin ratio. In conclusion, chronic cigarette smoking augments serum androgens and their 5α/β-reduced metabolites (including GABAergic substances) but suppresses the levels of estradiol in the LP and SHBG and may induce hyperandrogenism in female smokers., a2_The female smokers had pronouncedly increased serum progestogens but paradoxically suppressed levels of their GABA-ergic metabolites. Further investigation is needed concerning these effects., M. Dušková ... [et al.]., and Obsahuje seznam literatury
Increased homocysteine levels in serum are typical features of neurodegenerative brain diseases including hydrocephalus. The most frequent therapeutic approach consists of the insertion of a shunt, connecting the brain ventricles to an alternative drainage site. To decide whether the patient should undergo this, the lumbar drainage test is usually carried out to distinguish patients who can benefit from the shunt insertion. In searching for other potential biochemical markers for shunt indication we determined homocysteine levels in CSF during the lumbar drainage test. Homocysteine in CSF was measured during the 5-day lumbar drainage test in 27 patients with normal-pressure hydrocephalus (NPH) and in 25 patients with excluded hydrocephalus. A novelized gas chromatography method with flame ionization detection (GC-FID) was developed and evaluated. During the first two days of lumbar drainage, the levels of CSF homocysteine in NPH patients were significantly higher compared to the controls, while on the fifth day, the homocysteine levels in patients with hydrocephalus reached the level of controls. Determination of CSF homocysteine in patients with confirmed or suspected hydrocephalus may serve as an independent marker for deciding on their further treatment strategy., L. Sosvorová, J. Bešťák, M. Bičíková, M. Mohapl, M. Hill, J. Kubárová, R. Hampl., and Obsahuje bibliografii
Steroids are important marker s in pregnancy. Although estimating their levels separately in umbilical arterial (UA) and venous blood (UV) enable more precise insights into the functioning fetoplacental unit compared to using mixed umbilical blood (UM), selective aspiration of UA and UV is technically more demanding than collecting UM. We measured the levels of 67 unconjugated steroids and steroid polar conjugates in UA and UV using GC-MS in 80 women giving birth within weeks 28 to 42 of gestation. The samples were sorted into three groups: women entering labor within weeks 28- 32 (group A, n=19), weeks 33-37 (group B, n=19), and weeks 38-42 (group C, n=42) of gestation, respectively. The preterm labo rs were due to pathologies unrelated to steroid status. Most unconjugated steroids exhibited pronounced arteriovenous differences (AVD). The AVD were less distinct in more stable steroid conjugates. Most steroids positively correlate with gestational age, but unconjugated 5 β -reduced pregnanes show negative correlations, as do testosterone and androstenediol, substrates for the placental synthesis of estrogens. Tight correlations be tween steroids in UA and UV indicate that steroid measurements in UA, UV and UM can be accurately derived from each other, which is important for the diagnostics of steroid related diseases in newborns., A. Pašková ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy