Studies on the population dynamics of a thistle-feeding lady beetle,Henosepilachna pustulosa (Kôno) in a cool temperate climax forest

Population Ecology -     

Dipetalonema viteae: in vitro blastogenesis of hamster spleen and lymph node cells to phytohemagglutinin and filarial antigens

Hamsters of the randomly bred LAKZ and inbred LSH strains were infected with Dipetalonema viteae, and the in vitro responses of lymph node and spleen lymphocytes to male and female worm antigens and phytohemagglutinin (PHA) were measured by a [³H]-thymidine-uptake assay at various times after infection. The PHA response remained unchanged at the level of controls in infected LAKZ hamsters while LSH hamsters showed a depressed response to the mitogen during late infection. Stimulation of lymph node cells by filarial antigens was maximal in both strains of hamsters at Week 4 postinfection, almost reaching values obtained in PHA stimulated cultures. A similar high lymphocyte transformation reaction was measured after the injection of dead third stage larvae. During transient microfilaremia, when antibody titers reached a maximal level, the lymphocyte reactivity to filarial antigens decreased drastically and only occasionally was demonstrated in hamsters 20 and 30 weeks after infection. No correlation between lymphocyte reactivity and parasitological findings (worm load or intensity and duration of microfilaremia) could be demonstrated. The cellular unresponsiveness to filarial antigens was further analyzed in chronically infected LAKZ hamsters. No suppressor cells could be found in lymphocyte suspensions of nonresponding hamsters. A challenge infection did not restore lymphocyte reactivity. Serum of chronically infected hamsters caused marked inhibition when added to filarial antigen-sensitive lymphocytes. Lymphocytes from hamsters with a mixed D. viteae and Schistosoma mansoni infection responded as well to soluble schistosomal egg antigens at Week 30 of a D. viteae infection as lymphocytes from hamsters infected with S. mansoni alone. The humoral immune response to schistosomal antigens, however, was significantly lower in animals with a mixed infection.     

Social relationships between adult male and immature rhesus macaques

Social relationships of adult male rhesus macaques (Macaca mulatta) were studied over a period of 14 months. Sixteen focal males were chosen from a single group in the Cayo Santiago colony, Puerto Rico. Immatures were defined as infants, yearlings and 2-year-olds. There was a tendency for males to spend more time in proximity to immatures in the birth seasons than in the mating season. Time spent in proximity to immatures was correlated with male dominance rank. Several male-immature dyads had persistent relationships and nine were apparent throughout the study period. Most of the latter involved the top-ranking males. There were no consistent effects of sex or rank of the immature on the distribution of persistent relationships. In almost all male-immature dyads the immature was primarily responsible for maintaining proximity. Two ways were found in which immatures could benefit from these relationships. Protection and agonistic aiding of immatures by adult males were rare, but occurred exclusively in dyads with persistent relationships. In addition, immatures apparently gained greater access to food resources as a result of their relationships with adult males. There was no clear evidence of adult males benefiting from these relationships.     

Child growth and adult physique in Brazillan Xingu Indians

Data on stature, sitting height, biacromial width, and some other body measurements on 267 children and 363 adults of the Xingu Indians of Brazil have been analyzed. Adult height shows no significant decrease with age over an age range of 20–50 years, thus indicating the absence of secular changes. The average Xingu child seems to be around the twenty-fifth to fiftieth centile for height of British children (if our age estimates are correct) until about ten years in girls and 14 years in boys, but ends at below the third British centile as an adult. In sitting height, however, the Indians show substantially lower values, with children being at about the fifteenth centile until ten years in girls and 14 years in boys, while the adults are considerably below the British third centile. Other comparisons show that the Xingu are taller than Surinam Indians although of similar shoulder width. The lack of anthropometric data concerning South American Indian adults, and more especially children has been stressed. Investigations of these populations facing rapid acculturation and possible assimilation will form a baseline for the future work in public health as contacts with non-Indians increase.     

A fine structural survey of the development of the adult fat body of Leptinotarsa decemlineata

The fat body of a female Colorado potato beetle, Leptinotarsa decemlineata, at adult ecdysis, contains a large number of protein granules which are composed of light and dark zones. Part of the light zone in some of these granules is believed to be urate. During the first two days after adult ecdysis, fat body development is not essentially different in females reared either under long- or short-day conditions. Protein granules and large vacuoles disappear and the first cell organelles are regenerated. The effect of the photoperiod on the histological structure of the fat is expressed after these events. In females reared under long-day conditions, the fat body becomes specialized for vitellogenin synthesis. Under short-day conditions, the fat body stores massive amounts of lipid until day 6 after adult ecdysis. Then the first electron-dense protein granules develop near the nucleus, and on day 10 the first autophagic vacuoles are seen. These structure changes are discussed in connection with the known biochemical properties of the adult faty body of Leptinotarsa.     

Enrichment of subgingival microflora on human serum leading to accumulation of Bacteroides species,Peptostreptococci and Fusobacteria

This study was undertaken to identify ecological factors that favour opportunistic pathogenic species in the subgingival microflora. In a first approach, human serum as a substitute for gingival exudate, was used for batch-wise enrichment of subgingival plaque. The microflora resulting after 5–6 enrichment steps consisted of black-pigmented and non-black-pigmented Bacteroides species, Peptostreptococcus micros and Fusobacterium nucleatum as the main organisms. It is noted that the same group of species was found to be enriched independent upon the origin of the subgingival plaque sample. It was suggested that these organisms are favoured by the increased flow of gingival exudate during inflammation.The consortium of organisms was capable of selective degradation of serum (glyco-)proteins. Four different types of degradation occurred. After a prolonged period of growth complete degradation of immunoglobulins, haptoglobin, transferrin and complement C3c was observed. Partial degradation of immunoglobulins, haptoglobin, transferrin, albumin, alpha₁-antitrypsin and complement C3c and C4 was generally observed after 48 h of growth. Besides, immunoglobulin protease activity yielding Fc and Fab fragments was found. The consortium was also capable of consuming carbohydrate side-chains as indicated by an altered electrophoretic mobility of the serum glycoproteins.     

Decreased amount of vimentin N-terminal truncated proteolytic products in parkin-mutant skin fibroblasts

Vimentin, a member of cytoskeleton intermediate filaments proteins, plays a critical role in cell structure and dynamics.The present proteomic study reveals reduced amount of six different lengths, N-terminal truncated proteolytic products of vimentin, in the primary skin fibroblasts from two unrelated PD patients, as compared to control fibroblasts. The decreased amount of N-terminal truncated forms of vimentin in parkin-mutant fibroblasts, could contribute to impairment of cellular function, potentially contributing to the pathogenesis of Parkinson disease.