Comparison of calcium, freeze-thaw, and Triton X-100 tegumental disruption/recovery techniques applied to Schistosoma mansoni

Three techniques for the disruption/recovery of tegumental free-surface plasmalemma were compared by (i) morphological examination of carcasses and centrifugally-derived isolates, (ii) specific enrichment of bound surface tags (lectin) and of "marker" enzymes for membrane, and (iii) assessment of total protein and lectin recovered by each procedure. Procedures compared included the use of Triton X-100, freezing and thawing, and high ionic strength calcium. Triton X-100 consistently provided the greatest amounts of recovered surface membrane on a per worm basis, whereas calcium retained the highest amounts of alkaline p-nitrophenyl phosphatase, adenosine triphosphatase, and adenosine monophosphatase activity. Ultrastructural examination of membrane isolates and worm carcasses prepared by freezing and thawing indicated that significant amounts of parenchymal material contaminated the membrane fractions. Thus results based on the freeze-thaw technique can be difficult to interpret.     

Guaianolides from Saussurea affinis

Cynaropicrin, 11βH-11,13-dihydrodesacylcynaropicrin, aguerins A and B, isoamberboin and the new guaianolides saussureolide and 11βH-11,13-dihydrodesacylcynaropicrin 8-β-d-glucoside were isolated from Saussurea affinis.     

Bio-histopathological studies of endometrium in repeat breeding buffaloes (Bubalus bubalis)

A total of 24 uterine biopsies were successfully obtained from 40 repeat-breeding buffaloes. The endometrium of 15 buffaloes showed marked neutrophilic infiltration in the epithelium, stroma and uterine glands. In some cases, lymphocyte and plasma cell infiltration, cystic dilatation of the glands and periglandular fibrosis indicated chronicity of the endometritis. Most of the animals (85.0%) had uterine cultures positive for Streptococci, Staphylococci, Gram positive variable cocci, Gram negative bacilli, Anthracoids, and Gram positive bacilli with a predominance of Corynebacteria. With the treatment based on in vitro drug sensitivity tests, 57.1% repeat-breeding buffaloes conceived.     

Methylation of transfer RNA during transformation of human lymphocytes by phytohemagglutinin

Methylation of transfer RNA during phytohemagglutinin induced transformation of human lymphocytes was studied by labeling the tRNA $\text{in}\text{vivo}$ with (methyl-H³)-methionine and measuring the distribution of tritium in the methylated nucleotides. An alteration in the pattern of methylation occurred within hours after PHA-stimulation and this change was maintained through several cell generations. There was a 50 to 94% increase in the relative amount of methylated N²-methyl-guanine (1 to 3 hr) and a 40 to 59% decrease in the relative amount of 1-methyladenine (1 to 12 hr). Treatment of the stimulated cells with Actinomycin D prevented the subsequent methylation not tRNA. However, inhibition of protein synthesis by puromycin did not effect the early changes observed in the methylation of tRNA.     

Detection and Enumeration of Fecal Indicator Organisms in Frozen Sea Foods: II. Enterococci

Consistently high recoveries of enterococci as compared to the low numbers of coliforms obtained from the same samples of frozen sea foods are indirect evidence that enterococci are better indicators of contamination in such foods.

The use of azide dextrose broth, modified by the incorporation of bromthymol blue, and of ethyl violet azide broth as presumptive and confirmation tests, respectively, were found to be highly specific for the detection and enumeration of enterococci in these samples. Tetrazolium agar medium, when used as a third step after the confirmation test, provides a reliable differentiation of Streplococcus faecalis types from other group D streptococci. A simple procedure is described for further identification of S. faecalis varieties and other enterococcal species.

Incidence of biotypes within certain species is noted and relationships of these subgroups to the organisms described by other workers is discussed.

The striking resistance of all group D streptococci to dihydrostreptomycin and polymyxin B seems to offer promise for evolving a new selective medium for these organisms.

     

Occurrence of B-chromosomes in diploid Allium stracheyi Baker and their elimination in polyploids

Summary In a population of Allium stracheyi Baker (2n=14) growing in Darjeeling both diploids and polyploids occur. The diploids contain B-chromosomes varying from 2–10 in number. Polyploids are conspicuous by absence of B-chromosomes. These in diploids are found in the pollen mother cells and also in the pollen, and some are provided with subterminal constriction.Diploid individuals when brought from Darjeeling to Calcutta (i. e. from temperate to tropical regions) became polyploid within a month and the B-chromosomes were simultaneously lost. In order to confirm this unexpected result, the transfer experiment has been repeated thrice with fresh collections in each case and selection of diploid bulbs after cytological observation. In all cases the result has been the same. In rare cases one or two B-chromosomes were found in the polyploid cells which might represent intermediate steps of the disappearance.B-chromosomes in diploids possibly help the individual to compete with polyploids by enlarging the adaptive capacity.The sudden polyploidisation by transfer from the mountains to the plains might have been the result of a shock due to the temperature difference. The high temperature may be deleterious for the reproduction of B-chromosomes, and their degeneration products possibly contribute to cytoplasmic changes and the spindle disturbances which effect polyploidisation.