Relation of atherogenesis and T-immunodeficiency

Experiments on rabbits have shown that state of T-immunodeficiency induced by persisting virus infection promotes atherogenesis. Correction of age immunodeficiency by transplantation of the autologous bone marrow taken in young age considerably retards the atherosclerosis development. Inhibition of atherogenesis is also achieved by introduction (to animals) of natural thymic vilosene preparation which compensates a decrease in the functional activity of the thymus gland occurring under conditions of experimental hyperlipidemia.     

Effects of leucine-enkephalin and methionine-enkephalin on prolactin and gonadotropin secretion and synthesis in vitro

In vivo, Enkephalins, stimulate PRL, inhibit LH and are inactive on FSH. However, in monolayer pituitary cell cultures, PRL, LH and FSH secretions and synthesis are not modified by Met-Enk. (5 microgram/ml) or Leu-Enk. (5 and 10 microgram/ml). But the simultaneous presence of LHRH and Enk. induces an increase in LH secretion and synthesis without modifying FSH and PRL. In conclusion 1) Enk do not act by themself at the pituitary level but 2) they are able to modify the responses induced by hypothalamic hormones.     

Development of the subfornical organ and area postrema of the male albino mouse. Karyometric effect of neonatal and prepuberal castration

We have studied the karyometric development of the nuclei of the ependymal cells and neurons of the subfornical organ and the area postrema in the male albino mouse from the 5th to the 190th postnatal day. We have found similar patterns of development in both although the area postrema showed more significant postnatal oscillations than those of the subfornical organ, suggesting a more intimate chronological relationship to gonadal development. We have furthermore analyzed the development in two experimental groups: in the one animals were castrated at birth, in the other, castration was made on the 20th postnatal day. We have found that neonatal castration produced a significant decrease of nuclear sizes; this was more evident in the subfornical organ than in the area postrema in earlier stages of development while the response was similar in both at peripuberal ages. The response to prepuberal castration was similar in both organs.     

Ultrastructure of the epithelial cells of the ventral prostate from the hopping mouse Notomys alexis

The large ventral prostate of the hopping mouse has abundant secretory units whose epithelial cells vary in height and which often have nuclei in the apical region of the cell. TEM observations indicated two epithelial cell types in which some unusual features occurred. Type A cells had granular endoplasmetic reticulum (GER) whose membranes often formed intracytoplasmic confronting cisternae. Type B cells had more fragmented and vesiculated GER with sparse ribosomes and less frequently also intracytoplasmic confronting confronting cisternae. In the latter cells, two types of granules were found, one of which was derived from the Golgi and the other possibly directly from the GER. Type A cells only had one type of granule present. A highly convoluted membrane was also found at the basal region in many of the cells. The significance of these unusual ultrastructural features has yet to be ascertained.     

Establishment and yield of three ryegrasses following aldicarb use, and changes in abundance of plant parasitic nematodes

Pure swards of Lolium multiflorum, L. multiflorum var. westerwoldicum and L. perenne sown in August had greater yields than autumn on areas treated with either 5 or 10 kg a.i./ha aldicarb than on untreated areas. Total annual dry matter yields increased by larger amounts where the greater rate of aldicarb was applied; throughout the trial, L. perenne was usually less affected by treatment than the other two grasses. Plant-parasitic nematodes were more numerous on untreated than treated plots and were fewest in areas receiving the larger application (except in the second harvest year). Numbers of Tylenchorhynchus and Helicotylenchus were affected most by treatments; abundance of Paratylenchus and Criconemella were little altered. Stem-boring Diptera invaded tillers of all three grasses but infection was least in L. perenne. Invasion occurred only on untreated plots in the establishment year and some yield benefit probably resulted from their control. In subsequent years invasion was similar on treated and untreated areas. Effects on other, non-target organisms were not assessed. Ectoparasitic nematodes multiplied more in L. multiflorum plots than in others during the first full-harvest year. The next year numbers of Paratylenchus only were greater in plots of L. perenne than in other plots. Sward persistence of L. multiflorum var. westerwoldicum was better on treated than untreated areas. It was concluded a) that aldicarb use greatly decreased nematode numbers and yields from treated areas were larger than from those untreated; b) that sward persistence was similarly improved following aldicarb use and c) that ryegrasses differed in their suitability as hosts to ectoparasitic nematodes.