G6PD Cagliari: A new low activity glucose 6-phosphate dehydrogenase variant characterized by enhanced intracellular lability

Summary A new variant of human erythrocyte glucose 6-phosphate dehydrogenase (G6PD), designated G6PD Cagliari, has been characterized. It is associated with severe enzyme deficiency and can be placed in Class 2 of the usual tabulation of G6PD variants. The specific activity of this variant is near normal, while its decay within the circulating erythrocytes is very rapid compared with normals. Genetic analysis of the family of the propositus indicated that the two available females are heterozygotes characterized by extremely unbalanced mosaic phenotypes.     

Human C4 polymorphism: Pedigree analysis of qualitative,quantiative, and functional parameters as a basis for phenotype interpretations

Summary Ten families with 82 members were investigated for C4A- and B polymorphism in a blind trial. Phenotyping was done on neuraminidase treated sera by immunofixation and simulataneously by hemolytic overlay electrophoresis. In addition Rg, Ch, BF, C2, HLA-A, B, C, DR, and GLO were determined. After decoding the samples the reliability of blind typing was found to be 84.4% according to segregation patters. Inconsistencies occurred mostly when A 4, A 2, or A 92 were present. The detection of silent A*Q0 and B*Q0 alleles was more critical than that of difficult allotypes. The quantitation of the C4A/B ratio by densitometry of stained gels or by conventional immunochemical measurements of serum C4 level could not substantially improve the identification of A*Q0 or B*Q0. C4 dependent activity in radial diffusion hemolysis showed satisfactory correspondence with the number of expressed C4B alleles. At least three haplotypes with two C4A genes (duplicated A genes) were observed as ascertained from offspring analysis in accordance with the MHC segregation pattern. Individuals with the duplicated C4A gene (C4A*3. A*2. in the absence of any other expressed A allele or together with C4A*92) showed only partial inhibition of Rodgers antisera. Partial inhibition of Chido antisera was seen in individuals with C4B 2 (in the absence of other B allotypes). The findings support the hypothesis of at least two structural C4 loci. The also demonstrate the inconsistency of quantitative data in the recognition of silent alleles.     

Aspects of the biology of the euryhaline Asian cichlid,Etroplus suratensis

Synopsis Aspects of the biology of the euryhaline Asian cichlid Etroplus suratensis in a coastal lagoon of Sri Lanka were studied for a period of 15 months. Comparisons are made from the catches from the fishery of manmade, inland freshwater reservoirs. Changes in the stock structure in the sublittoral region of the lagoon indicate that recruitment takes place twice a year, during the high rainfall/low salinity periods. The feeding habits of E. suratensis were different in the two habitats. In the lagoon it fed mainly on molluscs and in the freshwater reservoirs on macrophytes. Feeding chronology based on diurnal surveys indicate that it feeds mainly during the daylight hours. The dentition of E. suratensis is adapted for both tearing and crushing (pharyngeal teeth). Distinct differences in the mean relative intestinal length between populations from the coastal lagoon and inland reservoirs were evident and these differences are correlated to their respective feeding habits. Diurnal changes in feeding activity are associated with changes in the stomach pH. The egg-diameter distribution of mature fish indicate that E. suratensis is a single spawner, that it sheds its mature eggs all at once. It is inferred that E. suratensis breeds twice a year but that an individual female is capable of spawning only once a year.     

Anatomical and physiological effects of silver thiosulfate on ethylene-induced abscission inColeus

Petioles of expiants ofColeus blumei Benth. exposed to 20 l/l ethylene abscised within 36 h. Pretreatment of expiants with 4 mM silver thiosulfate (STS) inhibited ethylene-induced abscission. Delaying treatment with STS reduced its effectiveness in retarding ethylene-promoted abscission, suggesting that some events leading to abscission are initiated during the first hours of ethylene treatment. Microscopic study of abscission zones of ethylene-treated expiants showed greatly increased amounts of rough endoplasmic reticulum, disruptions of the plasma membrane, and some cell separation in the region of the middle lamella. Pretreatment with STS prevented ethylene-induced reorganization of the endomembrane system and the subsequent middle lamellar dissolution.     

The fine structure of HNK-1 (Leu7) positive cells

Summary The ultrastructural characteristics of HNK-1 (Leu7) positive cells, visualized with a peroxidase labelled anti-mouse IgM serum, were analysed. Our investigation demonstrates: 1) the majority of Leu7 positive cells has a low nuclear/cytoplasmic ratio (N/C), an irregular outline, a well developed smooth endoplasmic reticulum, parallel tubular arrays (PTA) and electron dense granules; 2) the minority of Leu7 positive cells has a high N/C, regular profiles and lacks electron dense granules. The presence of two distinct ultrastructural patterns within Leu7 positive cells may represent: 1) the expression of subsequent stages of cell differentiation; 2) two distinct Leu7 positive cell subpopulations.     

β-Glucuronidase activity in human T and B lymphocytes and the Tμ and Tγ subpopulations

Summary The -glucuronidase staining characteristics of isolated T cell populations and the T and T enriched fractions derived of them were studied. T lymphocytes were obtained from purified T lymphocytes by ox-IgG rosette sedimentation. The rosette-forming cells in the pellet were referred to as T lymphocytes, whereas the lymphocytes in the interface were referred to as T depleted or T lymphocytes. B cells were studied on rosetted mononuclear cells with either mouse erythrocytes or with Staphylococcus Aureus (Cowan I) bacteria, after a preceeding polyvalent anti-human Ig treatment of the cells. While B cells showed mostly no reactivity, T and T cells were respectively characterised by a dot-like and granular pattern of reactivity. These findings are in agreement with those observed by others after -naphthyl-acetate esterase or acid phosphatase staining. Within the T lymphocyte fraction, the T non-, non lymphocytes seemed to have a granular pattern of reactivity. The same staining pattern was found in non-B, non-T lymphocytes.     

Isolation,culture, and preliminary characterization of ellipsoids (sheathed capillaries of Schweigger-Seidel) of the pig spleen

Summary Whole isolated ellipsoids (sheathed capillaries of Schweiger-Seidel) of the pig spleen were explanted in Medium 199 containing 20% fetal calf serum or horse serum respectively. Cultures were kept in a gas phase of 5% carbon dioxide in air at 37°C. After about 4 days in culture the outgrowth of two morphologically different cell types was apparent. Small cells of fusiform or stellate morphology disalayed high activity of acid phosphatase. N-acetyl--glucosaminidase and -glucuronidase activity were also detectable. Furthermore these cells were highly reactive for unspecific esterase and -glutamyl transpeptidase activity. Endogenous peroxidase activity was present in the cytoplasm and in the perinuclear space. Stellate cells therefore are thought of as ellipsoid macrophages. Additional observations reported are the expression of Fc-receptors on stellate cells. They triggered the phagocytosis of opsonized test particles. The second cell type showed fibroblastic morphology. The large well spread cells did exhibit low activities of acid phophatase and N-acetyl--glucosaminidase. The other enzyme activities examined were not detectable. The nature of these cells is not well understood at present. Most likely they are constituents of the framework of the ellipsoids. No transitions between stellate cells and fibroblastic cells were found.