Unions in Germany: Searching to regain the initiative

--

Scatter factor : molecular characteristics and effect on the invasiveness of epithelial cells

The generation of invasiveness in transformed cells represents an essential step of tumor progression. We have previously shown that MDCK epithelial cells, which are deprived of intracellular adhesion by the addition of anti-Arc-1/uvomorulin antibodies, become invasive for collagen gels and embryonal heart tissue (Behrens, J., M. M. Mareel, F. M. Van Roy, and W. Birchmeier. 1989. J. Cell Biol. 108: 2435-2447.). Here we examined whether invasiveness is also induced by scatter factor, which is known to dissociate epithelial cells (Stoker, M., E. Gherardi, M. Perryman, and J. Gray. 1987. Nature (Lond.). 327:239-242.). Scatter factor was purified to homogeneity from conditioned medium of human fibroblasts by heparin-Sepharose chromatography, followed by cation exchange chromatography, gel filtration, or preparative SDS gel electrophoresis. We found that scatter factor represents a 92,000 mol wt glycoprotein which, apparently, is converted by limited proteolysis into disulfide-linked 62,000 and 34/32,000 mol wt subunits. Reversed phase HPLC and sequence analysis of tryptic peptides confirmed the suggested molecular structure, and revealed further that scatter factor exhibits sequence similarities to hepatocyte growth factor and to plasminogen. Purified scatter factor in fact induces the invasiveness into collagen matrices of MDCK epithelial cells, and induces or promotes the invasiveness of a number of human carcinoma cell lines. Apparently, the effect on the human cells depends on their respective degree of differentiation, i.e., cell lines with a less pronounced epithelial phenotype were more susceptible to the factor. Scatter factor does not seem to influence synthesis, steady-state level, and phosphorylation of the cell adhesion molecule Arc-1/uvomorulin. Thus, scatter factor represents a clearly defined molecular species which induces, in vitro, the progression of epithelial cells to a more motile, i.e., invasive phenotype

Hormonal and uterine changes in pregnant and pseudopregnant gilts treated with hydrocortisone acetate

In the first experiment 11 gilts were injected with 5 mg of estradiol benzoate on d 11-15 of the estrous cycle to induce pseudopregnancy. Twice daily on d 21-30 gilts were administered either 5 mg per kg bodyweight (avg. wgt 120 kg) hydrocortisone acetate (HA) in sesame oil (5 ml) or sesame oil (control) subcutaneously (SQ). Blood samples (20 ml) were collected via jugular puncture on d 11, 21, and 31. Uterine flushings were obtained surgically the day following the last day of treatment (d 31). Twice daily injection of HA on d 21-30 significantly (p\u3c.001) elevated cortisol levels above that of control animals in plasma and uterine flushing on d 31. The percent distribution of cortisol in plasma [% unbound (UB-C), % corticosteroid binding globulin (CB6) bound (CBG—C), and % albumin bound (Alb-C)] was not different between treatments. Plasma CBG binding capacity (CBG-BC) was lower (p\u3c.001) following 10 d of treatment with HA compared to control gilts (7.4 versus 38.7 pmol/ml). Plasma progesterone (P4) levels were significantly (p\u3c.01) lower in HA treated gilts (8.9 ng/ml) compared to control gilts (17.8 ng/ml). Uterine Flush P4 levels were also decreased (p\u3c.001) compared to control gilts. Total plasma protein and albumin concentrations were similar (p\u3e.05) to control gilts. Total proteins in the uterine flush were lower (p\u3c.001) in HA treated gilts. Corpora lutea (CL) number and concentrations were not affected by treatment. Total CL weight was significantly (p\u3c.01) lower in HA treated gilts compared to control animals. In the second experiment 18 crossbred gilts exhibiting 2 normal estrous cycles (18-23 d) were naturally bred to a mature boar and randomly assigned to receive 5 mg/kg bodyweight (BW) HA (Trt 1), 2.5 mg/kg BW HA (Trt 2), or 5 ml sesame oil (control; Trt 3) twice daily on d 9-13 of pregnancy. Blood samples were collected on d 9, 11/ 13, and 20 of pregnancy. On d 46 ± 2 gilts slaughtered and reproductive tracts collected. CL number and CL weights were obtained. Number, weight, crown rump length, placental weight, allantoic and amniotic fluid volume of fetuses were measured and recorded. Plasma cortisol levels were increased (p\u3c.05) due to treatment on day 13. The distribution of cortisol (% UB-C, % CBG-C, and % Alb-C) was not different (p\u3e.05) between treatments. CBG-BC, plasma P4 levels, total proteins, CL number, CL weight, fetal number, fetal length, and placental weight were not affected by treatment. Fetal weights in Trt 2 (2.5 mg/kg HA) were significantly (p\u3c.05) lower compared to Trt 1 (5 mg/kg HA) and control gilts. Allantoic and amniotic fluid volumes were lower in Trt 2 (p\u3c.001 and p\u3c.05, respectively) compared to Trt 1 and control gilts. These results suggest that : a) HA affected P4 production in the ovary by retarding CL development, B) the HA treatment lowered total P4 output, as reflected by lowered P4 concentration in the plasma, and affected protein secretion in the uterus, C) uterine protein secretions were preferentially reduced in the component contributed by P4-induced, locally synthesized proteins but not by serum transudate, D) HA did not affect liver function as measured by total plasma protein concentration, E) HA affected CBG as evident by the decrease in CBG-BC concentrations and F) reduction in uterine secretory protein output may result in lowered fetal weight due to poor nutrition in utero

What early life history tells us about restoration success in Olympia oysters

Native Olympia oysters have been the subject of widespread restoration efforts across the west coast, including in the Salish Sea. The ultimate goal of restoration is to establish populations that are self-sustaining or even exporting new offspring to other appropriate habitats. It is difficult to study the early life history of marine invertebrates, which have a microscopic and planktonic larval form and often episodic settlement pulses. However, being able to predict larval behaviors and settlement preferences can allow practitioners to design habitats, choose sites, and distribute restoration networks more effectively. The purpose of this study, a collaboration among academic and non-profit organizations, was to map the spatial and temporal distribution of oyster larvae and settlers in Fidalgo Bay. This bay has been the subject of restoration work over the past decade and has experienced high levels of settlement since the project began. From April through July 2013, we monitored the reproductive state of adults and the relative abundance and distribution of larvae and spatfall. Larvae were collected in larval tube traps and using a plankton pump; the number of larvae were quantified using real-time quantitative PCR. Settlers were sampled using shell strings made of adult Pacific oyster shells that were examined visually. Analyses are ongoing, although studies of adults show low reproductive synchrony, even during peak spawning. Settler data revealed that juvenile oysters settled preferentially near adult oysters rather than across depths and locations as previous studies have indicated. We will compare larval distribution data to determine if larvae are distributed throughout the area and are preferentially settling in optimal habitat, or if they remain in specific areas throughout the dispersal period. These results will be used to improve restoration efforts and to design future studies of larval dispersal of this important ecosystem engineer