Endometrial and placental protein markers and ovarian steroids in serum during in-vitro fertilization cycles

The objective of this study was to find the earliest time at which it was possible to detect clinical pregnancy in an in-vitro fertilization (IVF) treatment cycle supported with human chorionic gonadotrophin (HCG), and also retrospectively to diagnose abnormal ovarian- or endometrium-related situations in failure cycles. Serum samples were taken in 41 IVF cycles at frequent intervals from the beginning of ovarian stimulation until menstrual bleeding occurred or a pregnancy was established. Concentrations of oestradiol, progesterone, placental protein 14 (PP14), pregnancy-specific beta 1-glycoprotein (SP1), and pregnancy-associated plasma protein A (PAPP-A) were determined in the serum samples using commercially available (steroid) or purpose-developed (protein) immunoassays. The cycles were retrospectively distributed into four outcome groups: (i) fertilization failure (FF, n = 8); (ii) implantation failure (IF, n = 10); (iii) 'interaction' (embryo-endometrium) cycle (IC, n = 14), and (iv) clinical pregnancy (CP, n = 9). The embryo-endometrium interaction was detected by a rise in SP1 in 23 cycles (70% of embryo transfers) at a time when endogenous HCG was still masked by external support. Early ('false') positive SP1 concentrations were observed in two out of eight and five out of 14 cases in groups FF and IC respectively, but never amongst the ongoing pregnancies (CP). PAPP-A did not distinguish pregnancy from the other outcomes. The PP14/progesterone ratio was lower, later in the cycle, in CP than in the other groups.(ABSTRACT TRUNCATED AT 250 WORDS)     

Platelet survival and morphology in homocystinuria due to cystathionine synthase deficiency

In homocystinuria due to cystathionine synthase deficiency thromboembolism is a major cause of mortality and morbidity. Recent studies by others identified an abnormally shortened platelet survival and increased platelet vacuolization in patients with homocystinuria. When we studied six additional patients, however, we found the platelet survival to be within normal limits for each. The mean survival (+/-1 S.D.) was 9.75+/-0.94 days (normal, 9.27+/-1.06). In addition, platelets from five patients with homocystinuria and three obligate heterozygotes could not be distinguished from those of seven normal control subjects by electron microscopy. Specifically, no increased vacuolization was observed. Genetic heterogeneity, technical differences of differences in plasma homocystine concentrations could account for these descrepant results. The mechanism of thrombosis in homocystinuria remains an open question.     

Effect of poultry waste feeding on intake, body weight and milk yield of Holstein cows

Forty lactating Holstein cows were fed 0, 5.9, 11.7, or 17.4% processed poultry excreta in total mixed rations. The effect of treatment was evaluated on feed intake, BW, milk yield, and composition. Processes poultry excreta appeared to be well accepted by cows even when included in rations at 17.4% of total DM. Mean DM intake averaged 19.3, 19.7, 19.5, and 19.7 kg/d for cows fed 0, 5.9, 11.7, and 17.4% processed poultry excreta, respectively. Body weight change averaged 2.0, 1.7, -1.7, and 1.4 kg/wk from 90 to 180 d of lactation for cows fed from 0 to 17.4% processed poultry excreta, respectively. Fat-corrected milk (4%) yield was similar among treatment groups, averaging 24.2, 26.1, 24.6, and 25.1 kg/d for cows fed 0, 5.9, 11.7, and 17.4% processed poultry excreta. No differences were found for milk and fat yields of percentage fat among treatment means. No off flavors in milk could be attributed to processed poultry excreta added to feed. Processed poultry excreta fed up to 17.4% of total mixed rations supported both adequate feed intake and high milk yields of mid-lactation cows.     

Platelet-derived growth factor stimulates the release of protein kinase A from the cell membrane

The mitogenic action of growth factors involves the stimulation of intracellular protein kinases. In this report we have characterized the major protein kinase released from Balb/c 3T3 and normal rat kidney plasma membranes by the action of platelet-derived growth factor (PDGF). PDGF appears to stimulate the release of approximately 10 proteins, at least one of which is a kinase capable of phosphorylating proteins on Ser or Thr (as determined by the lability of the phosphate to alkali treatment). More than 90% of the Ser/Thr kinase activity was inhibited by PKI5-22, a specific peptide inhibitor of the cAMP-dependent protein kinase (PKA). We used immunoblotting to confirm that the kinase released in response to PDGF was PKA. cAMP also stimulated the release of PKA, and the set of protein substrates phosphorylated was similar following PDGF or cAMP stimulation. Interestingly, in the presence of a cAMP analogue ((Rp)-cAMPS), cAMP could not induce dissociation of PKA from the membranes, whereas stimulation by PDGF increased the level of PKA activation. Furthermore, unlike Swiss 3T3 cells, neither Balb/c 3T3 fibroblasts nor normal rat kidney cells accumulate cAMP in response to PDGF, yet the level of PKA in the cytosol of these intact cells increases in response to PDGF. Thus, it appears as though PDGF activation of the membrane-associated form of the PKA holoenzyme occurs by a mechanism independent of an elevation in cAMP levels.     

The localization of cholinesterase in the retina of the fetal and newborn guinea pig

Retinae of guinea pigs from the fortieth day of gestation to one day postnatally were processed for the localization of cholinesterases in the electron microscope according to the method of Lewis and Shute ('66). Selective inhibition served to distinguish acetylcholinesterase from non-specific cholinesterase activity. Acetylcholinesterase activity was found initially in small amounts in some regions of the outer plexiform layer at the fortieth day of gestation. At later stages it increased in distribution being observed at some photoreceptor terminals and in non-synaptic regions of the layer. Activity was less intense initially in the inner plexiform layer but increased rapidly so that by birth it encompassed a majority of processes. Perikarya of horizontal and some amacrine and ganglion cells possessed acetylcholinesterase activity in their nuclear envelope and rough endoplasmic reticulum. The possible role of the enzyme in inhibitory circuits of the fetal retina is discussed.     

Cerebral nematodiasis in captive nutria

Of 35 nutria (Myocaster coypus) at a city zoo, 20 died or were killed because of a progressive central nervous system disease. On the basis of histopathologic findings, a diagnosis of cerebral nematodiasis complicated by nosematosis was made. The only significant management change prior to illness was the feeding of poplar tree branches from a lowland area inhabited by skunks and raccoons. Neurologic disturbances gradually ceased within 2 months after control measures were initiated and the practice of provided poplar branches as a source of roughage was discontinued.