a1_Progesterone and estradiol are the foremost steroid hormones in human pregnancy. However, the origin of maternal progesterone has still not been satisfactorily explained, despite the generally accepted opinion that maternal LDL-cholesterol is a single substrate for placental synthesis of maternal progesterone. The question remains why the levels of progesterone are substantially higher in fetal as opposed to maternal blood. Hence, the role of the fetal zone of fetal adrenal (FZFA) in the synthesis of progesterone precursors was addressed. The FZFA may be directly regulated by placental CRH inducing an excessive production of sulfated 3β-hydroxy-5-ene steroids such as sulfates of dehydroepiandrosterone (DHEAS) and pregnenolone (PregS). Due to their excellent solubility in plasma these conjugates are easily transported in excessive amounts to the placenta for further conversion to the sex hormones. While the significance of C19 3β-hydroxy-5-ene steroid sulfates originating in FZFA for placental estrogen formation is mostly recognized, the question “Which maternal and/or fetal functions may be served by excessive production of PregS in the FZFA?“ - still remains open. Our hypothesis is that, besides the necessity to synthesize de novo all the maternal progesterone from cholesterol, it may be more convenient to utilize the fetal PregS. The activities of sulfatase and 3β-hydroxysteroid dehydrogenase (3β-HSD) are substantially higher than the activity of cytochrome P450scc, which is rate-limiting for the placental progesterone synthesis from LDL-cholesterol. However, as in the case of progesterone synthesis from maternal LDL-cholesterol, the relative independence of progesterone levels on FZFA activity may be a consequence of substrate saturation of enzymes converting PregS to progesterone., a2_Some of the literature along with our current data (showing no correlation between fetal and maternal progesterone but significant partial correlations between fetal and maternal 20α-dihydroprogesterone (Prog20α) and between Prog20α and progesterone within the maternal blood) indicate that the localization of individual types of 17β-hydroxysteroid dehydrogenase is responsible for a higher proportion of estrone and progesterone in the fetus, but also a higher proportion of estradiol and Prog20α in maternal blood. Type 2 17β-hydroxysteroid dehydrogenase (17HSD2), which oxidizes estradiol to estrone and Prog20α to progesterone, is highly expressed in placental endothelial cells lining the fetal compartment. Alternatively, syncytium, which is directly in contact with maternal blood, produces high amounts of estradiol and Prog20α due to the effects of type 1, 5 and 7 17β-hydroxysteroid dehydrogenases (17HSD1, 17HSD5, and 17HSD7, respectively). The proposed mechanisms may serve the following functions: 1) providing substances which may influence the placental production of progesterone and synthesis of neuroprotective steroids in the fetus; and 2) creating hormonal milieu enabling control of the onset of labor., M. Hill ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy
Výzkumná studie vychází z problému nezaměstnanosti. Obzvláště obtížná je situace u osob dlouhodobě nezaměstnaných se zdravotním postižením. Jde o osoby, na něž je třeba se zaměřovat především s důrazem na uplatnitelnost na trhu práce. Výzkumný soubor tvořilo 240 dlouhodobě nezaměstnaných osob se zdravotním postiţením (minimálně 12 měsíců od registrace na úřadě práce, 120 mužů a 120 žen, průměrný věk 45 let). Data byla zjišťována prostřednictvím metody Sparo. Na základě této metody bylo hlavním cílem výzkumu zjistit podobné osobnostní vlastnosti u této skupiny osob v porovnání s populační normou. Z podstatných zjištění vyplývajících z osobnostních vlastností v závěru předpokládáme, že je u těchto osob reálně spíše nemožné očekávat samostatnou zvýšenou aktivitu při vyhledávání zaměstnání, a proto se jeví jako velmi nutná potřebná zvýšená pomoc ve formě pracovně profesního a psychologického poradenství. and The research study focuses on the issue of unemployment. Particularly difficult is the situation of the long-term unemployed people with disabilities. These are the people we mainly need to focus on, regarding their employability. The research study is based on a sample of 240 respondents who were unemployed and disabled (at least 12 months registered at the Labour Office, 120 men and 120 women, average age 45). The data were obtained through the method called Sparo. Using this method, the main task was to identify similar personality traits of the disabled long-term unemployed compared to the population norms.
Based on the final findings derived from personal traits we assume, that with these people it is almost impossible to expect increased activity from their side while looking for a job and that is why the need for increased help in the form of professional and psychological counseling is needed. For this group we find as very helpful high assistance in professional and psychological counseling.
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