Hormone changes in relation to the time of fetal death after prostaglandin-induced abortion

The changes in unconjugated estradiol-17beta and estriol, progesterone and chorionic somatomammotropin (HCS) in peripheral plasma have been studied in 18 women at 30-minute intervals following intra-uterine prostaglandin E2 administration for therapeutic termination of second trimester pregnancy. The hormonal changes were related to the time of fetal death detected by the disappearance of fetal heart pulsations. Prostaglandin E2 was given by the intra-amniotic route with urea (5 patients) or with intravenous oxytocin (5 patients), or by the extra-amniotic route with intravenous oxytocin (8 patients). Fetal death occurred rapidly with intra-amniotic PGE2, but usually at a late stage with extra-amniotic PGE2. Three fetuses in the extra-amniotic group died at or just before abortion. A variety of fetal heart changes were noted and the time of fetal death did not appear to influence the time of abortion within each treatment subgroup. Estradiol and estriol showed a sligh but persistent fall over 24 hours prior to induction of abortion. A more rapid fall usually occurred after induction, with a consistent fall around the time of fetal death. Progesterone and HCS usually fell much less before and immediately after fetal death. A marked rise in estradiol sometimes occurred before fetal death, particularly in the intraamniotic PGE2 and urea subgroup. Estriol levels declined more rapidly before than after fetal death, whereas fetal death had less consistent effects on the other hormones. All hormones had usually fallen considerably at the time of abortion, and in some individuals marked fluctuations in hormone levels were seen.     

The Glu318Gly mutation of the presenilin-1 gene does not necessarily cause Alzheimer's disease

In early-onset familial Alzheimer's disease (AD) pathogenic mutations have been found in the amyloid precursor protein (APP) gene and in the presenilin (PS)-1 and PS-2 genes. We screened for mutations in these genes in 20 patients with familial AD from the Finnish population. In addition, we sampled 41 sporadic AD patients and 59 controls to test for mutations identified in our familial AD cases. We detected an A-to-G transition in the PS-1 gene, resulting in a glutamic acid (Glu)-to-glycine (Gly) substitution at codon 318 in 2 familial and 2 sporadic AD patients. The Glu318Gly mutation has previously been reported to cause AD. We also found the Glu318Gly mutation in 4 healthy aged controls (range, 74-87 years). We thus conclude that the mutation is most likely a rare polymorphism not related to AD.     

Testosterone and testosterone precursors in the spermatic vein and in the testicular tissue of old men. Reduced oxygen supply may explain the relative increase of testicular progesterone and 17 alpha-hydroxyprogesterone content and production in old age

Testosterone and the testosterone precursors pregnenolone, progesterone, 17 alpha-hydroxyprogesterone, 17 alpha-hydroxypregnenolone, androstenedione, androstenediol and dehydroepiandrosterone were measured in the spermatic vein plasma and in the testicular tissue of young and old men. Testosterone and its precursors decreased in the testicular tissue of old men. However, progesterone and 17 alpha-hydroxyprogesterone increased in relation to testosterone in the testicular tissue and in the spermatic vein of old men. It is assumed that these age-dependent changes are caused by an impaired oxygen supply of the ageing testes. This hypothesis is supported by the observation that the same changes in steroid pattern seen in old age can be observed under reduced oxygen supply in in vitro incubation experiments with testicular tissue.     

Regulation and function of steroid production by mid gestation ovine fetal adrenal cortex in vivo

By mid-gestation (75-85 days, term=150 days), the ovine fetal adrenal gland is zoned into cortex and medulla. The cortex has an outer layer of cells which have the morphological characteristics of zona glomerulosa cells, containing mitochondria with lamellar cristae. It has been reported that cultured adrenal cells from mid-gestation bovine and ovine fetuses can be stimulated to increase aldosterone production, ten fold, by angiotensin II, and that this can be maintained for at least 3 days. However, the situation in vivo is unknown. In the current report we show that in chronically cannulated ovine fetuses at mid-gestation, angiotensin II (1 microg/h) does not increase aldosterone either in the short term (3 hours) or long term (3 days). However, ACTH (450 ng/h) can increase plasma aldosterone in the short but not long term. ACTH at this dose produces progressive and large increases in cortisol production. Angiotensin II is pressor and produces a modest diuresis without stimulating cortisol.     

Cooperative thermal transitions of bovine and human apo-alpha-lactalbumins: evidence for a new intermediate state

The thermal denaturation of bovine and human apo-alpha-lactalbumins at neutral pH has been studied by intrinsic protein fluorescence, circular dichroism (CD), and differential scanning microcalorimetry (DSC) methods. Apo-alpha-lactalbumin possesses a thermal transition with a midpoint about 25-30 degrees C under these conditions (pH 8.1, 10 mM borate, 1 mM EGTA), which is reflected in changes in both fluorescence emission maximum and quantum yield. However, the CD showed a decrease in ellipticity at 270 nm with a midpoint at about 10-15 degrees C, while DSC shows the transition within the region of 15-20 degrees C. The non-coincidence of transition monitored by different methods suggests the existence of an intermediate state in the course of the thermal denaturation process. This intermediate state is not the classical molten globule state which occurs at higher temperature (i.e. denatured state at these conditions) [D.A. Dolgikh, R.I. Gilmanshin, E.V. Brazhnikov, V.E. Bychkova, G.V. Semisotnov, S.Y. Venyaminov and O.B. Ptitsyn, FEBS Letters, 136 (1981) 311-315] and has physical properties intermediate between the native and molten globule states.     

Nanoparticle-based continuous full filling capillary electrochromatography/electrospray ionization-mass spectrometry for separation of neutral compounds

Highly efficient reversed-phase capillary electrochromatography (CEC) separations (plate numbers up to 700 000/m), with electrospray ionization mass spectrometry detection were achieved utilizing novel dextran-coated polymer nanoparticles as a pseudostationary phase. A continuous full filling (CFF) technique in which nanoparticles are continuously introduced into the capillary was employed for separation of neutral analytes (dialkyl phthalates), utilizing an orthogonal electrospray interface to prevent nanoparticles from entering the mass spectrometer. CFF-CEC benefits from that an entirely fresh column is employed for every analysis, avoiding carryover effects associated with stationary-phase contamination. The highly efficient separations obtained were accomplished by optimizing the organic modifier concentration in the electrolyte and by using a high nanoparticle concentration (5 mg/mL), to improve interparticle mass transfer and gain sufficient retention. Nanoparticles, with an average diameter of 600 nm, were prepared by polymerization of methacrylic acid and trimethylolpropane trimethacrylate, which in turn were coated with dextran. These nanoparticles formed stable suspensions in electrolytes having broad ranges of polarities, enabling straightforward optimization of the reversed-phase conditions.     

The epidermal growth factor receptor is not required for tumor necrosis factor-alpha action in normal mammary epithelial cells

Our laboratory has shown that tumor necrosis factor-alpha (TNF alpha) can regulate normal mammary epithelial cell (MEC) growth, morphogenesis, and, under certain circumstances, functional differentiation in a manner similar to epidermal growth factor (EGF). As TNF alpha has been shown to up-regulate EGF receptor (EGFR) expression and function in other systems, the present studies were undertaken to determine whether TNF alpha action in MEC was indirect through stimulation of the EGFR. An inhibitor of EGFR tyrosine kinase activity, PD158780, failed to block proliferation induced by 40 ng/ml TNF alpha and only partially inhibited growth in response to 2 ng/ml TNF alpha. PD158780 was also unable to suppress the extensive morphological development induced by either TNF alpha concentration. In contrast, the effects of TNF alpha and PD158780 on functional differentiation (i.e. casein accumulation) were time dependent. When measured on day 7 after 48 h of treatment, casein accumulation was unaffected by either concentration of TNF alpha or by PD158780. When assessed on day 21 after 16 days of treatment, however, casein levels were decreased by 40 ng/ml TNF alpha and increased by PD158780. Significantly, this PD158780-induced increase in casein was not observed in MEC that had been treated with both PD158780 and TNF alpha. These results thus suggest that EGFR tyrosine kinase activity is not necessary for TNF alpha action in normal MEC.