Silage studies. IV. The microflora on the surface of some fodder plants at different stages of maturity

Summary A comparison is made of the bacterial populations on the surface of some fodder plants and the populations on corresponding plant materials after collecting into a silo.Estimations are made of the total number of bacteria and fungi, and of the number of lactic acid bacteria and spore-forming anaerobes.The equilibrium between acidifying and ammonifying organisms is discussed. Antibiotic phenomena within the floras have been studied.These studies are still in progress. We are indebted to the Swedish Foundation: Fonden för främjande av forsknings- och försöksverksamheten på jordbrukets område for generous financial support. We also gratefully acknowledge the encouraging interest and support of ProfessorRagnar Nilsson.     

Über Glykoproteideinschlüsse in den Trophoblastzellen der menschlichen Plazenta und die Frage ihres Zusammenhangs mit der Bildung von Gonadotropin

Summary In some of the basophilic trophoblastic cells of the basal plate and islands of the mature human placenta there are glycoprotein inclusions, many of which are within vacuoles. As established by the histochemical results these inclusions are composed of a neutral mucopolysaccharide and a basophilic protein with SH groups. They gradually increase in number from the 4th month of pregnancy and are not influenced by labor. From the first to the fourth month of gestation small vacuoles, initially infra-nuclear but later supranuclear, may be seen in the syncitial cells of the villi; these likewise contain glycoprotein granules. The same inclusions are to be found in some trophoblastic cells of the chorionic plate and of the chorion laeve, and in an occasional epithelial cell of the amnion.On the basis of the histochemical behavior of these inclusions, their similarity with the -granules of the hypophysis, and the obvious high activity of the trophoblastic cells which bear them, it is postulated that these inclusions contain gonadotropin. Their occurrence during pregnancy parallels the biochemical concentration and immunofluorescent histological demonstration of gonadotropin in the placenta. Thus, at the end of pregnancy the basal trophoblastic cells of the human placenta appear to form at least two different hormones: relaxin, probably represented morphologically by the acidophilic protein inclusions (described elsewhere), and gonadotropin most likely represented by the basophilic glycoprotein inclusions.     

High affinity interaction with filamin A protects against calcium-sensing receptor degradation

Calcium-sensing receptors (CaR) regulate cell proliferation, differentiation, and apoptosis through the MAPK pathway. MAPK pathway activation requires the cytoskeletal scaffold protein filamin A. Here we examine the interactions of CaR with filamin A in HEK-293 and M2 or A7 melanoma cells to determine how interactions with filamin A facilitate signaling. Filamin A interacts with CaR through two predicted beta-strands from residues 962 to 981; interactions between filamin A and CaR are greatly enhanced by exposure to 5 mM Ca2+. Truncations or deletions (from 972 to 997 or 962 to 981) of the CaR carboxyl terminus eliminate high affinity interactions with filamin A, but CaR-mediated MAPK pathway activation still occurs. CaR-mediated ERK phosphorylation can be localized to a predicted alpha-helix proximal to the membrane, which has been shown to be important for G protein-mediated signaling (residues 868-879). In M2 cells (-filamin A), CaR expression levels are very low; cotransfection of CaR with filamin A increases total cellular CaR and increases plasma membrane localization of CaR, facilitating CaR signaling to the MAPK pathway; similar results were obtained in HEK-293 cells. Interaction with filamin A increases cellular CaR by preventing CaR degradation, thereby facilitating CaR signaling. In addition, filamin A facilitates signaling to the MAPK pathway even by CaR truncations or deletion mutants that cannot engage in high affinity interactions with filamin A, suggesting the targeting of critical signaling proteins to CaR.     

Effects of G2-checkpoint dynamics on low-dose hyper-radiosensitivity

Journal of Mathematical Biology - In experimental studies, it has been found that certain cell lines are more sensitive to low-dose radiation than would be expected from the classical...     

Uptake of six heavy metals by oat as influenced by soil type and additions of cadmium,lead, zinc and copper

Summary The influence of heavy metal additions on availability and uptake of cadmium, lead, zinc, copper, manganese and iron by oat was studied. The experiments were carried out as pot experiments using sandy loam, sandy soil and organic soil. Selective extractants were used to remove metals held in different soil fractions.Lead and copper were preferently bound by organics and oxides, zinc by oxides and inorganics, and cadmium by inorganics and organics.Addition of cadmium to the soils resulted in higher cadmium concentrations in all plant parts but lower concentrations of lead, zinc, copper, manganese and iron, and the accumulation indexes of these metals were also lower when cadmium was added to the soil.Addition of cadmium plus lead, zinc and copper resulted in higher cadmium concentrations in leaves and straw of plants grown in sandy loam and sandy soil, but lower concentrations when plants were grown in organic soil as compared with the results when cadmium was added separately. The transfer of cadmium, lead, zinc and copper from soil to plant was greatest from sandy soil, and zinc and cadmium were more mobile in the plant than were lead and copper.Cadmium concentrations in leaves correlated significantly with CaCl₂ and CH₃COOH extractions in sandy loam and sandy soil and with CH₃COOH extractions in organic soil.Generally, the total metal uptake was lowest from organic soil.