DoesAgapetus fuscipes cultivate algae in its case?

The presence of algae within the cases ofAgapetus fuscipes was investigated. Cases recognised as dirty or clean with the naked eye had more and less algal growth, respectively. Larvae in the former survived significantly longer when starved in the laboratory. It is suggested that the presence of algae within the cases would be of ecological advantage during periods of flood.     

Identification of psychrotrophic pseudomonads from goats' milk by computer-assisted analysis of carbon source assimilation data

The results of carbon source assimilation tests on a group of psychrotrophic pseudomonas were compared with published data for established Pseudomonas taxa, using computer-assisted numerical taxonomic analysis and a modified diagnostic computer program. Several phenons were not grouped at the biovar level by numerical taxonomic analysis. Identification of strains by the diagnostic program revealed heterogeneity among those in the unassigned phenons, and supported a continuum concept among the fluorescent pseudomonads.     

A numerical taxonomic study of proteolytic and lipolytic psychrotrophs isolated from caprine milk

Lipolytic and proteolytic psychrotrophs were isolated from raw and pasteurized goats' milk, which had been stored at 5 degrees C for 7 d. The 241 strains isolated and 20 reference strains were examined by 149 biochemical, physiological, and morphological tests. The results yielded 195 characters suitable for taxonomic analysis. Computer-assisted complete linkage analysis, using the Jaccard coefficient, produced 22 phenons at 75% S. The results showed that Pseudomonas fluorescens was the predominant psychrotrophic bacterium, but that Pseudomonas fragi was dominant in some milk samples. Strains of Serratia liquefaciens and Flavobacterium balustinum were also identified.     

Characterization of Holliday structures in FLP protein-promoted site-specific recombination.

Holliday structures are formed in the course of FLP protein-promoted site-specific recombination. Here, we demonstrate that Holliday structures are formed in reactions involving wild-type substrates and that they are kinetically competent with respect to the overall reaction rate. Together with a previous demonstration of chemical competence (L. Meyer-Leon, L.-C. Huang, S. W. Umlauf, M. M. Cox, and R. B. Inman, Mol. Cell. Biol. 8:3784-3796, 1988), Holliday structures therefore meet all criteria necessary to establish that they are obligate reaction intermediates in FLP-mediated site-specific recombination. In addition, kinetic evidence suggests that two distinct forms of the Holliday intermediate are present in the reaction pathway, interconverted in an isomerization process that is rate limiting at 0 degree C.     

Kinetic analysis of the cerebral creatine kinase reaction under hypoxic and hypoglycaemic conditions in vitro. A 31P-n.m.r. study.

1. The tissue concentration of phosphocreatine (PCr) and the pseudo-first-order rate constant of creatine kinase (kf) were monitored in superfused guinea-pig brain slices in vitro by using 31P-n.m.r. techniques. 2. Superfusion of slices in low oxygen partial pressure (pO2 approx. 16 kPa) decreased tissue PCr concentrations by 48% but ATP concentrations were unchanged. Regression analysis revealed a significant negative correlation between the PCr concentration in hypoxic tissue and the increase in the rate constant, kf. Nevertheless the forward flux through the enzyme (Jf = kf.[PCr]) declined under these conditions. 3. Lowering the glucose concentration to 0.2 or 0.1 mM decreased PCr concentrations by 29% and 48% respectively; here ATP concentrations as well as PCr concentrations also decreased. Only in the presence of the lower glucose concentration (0.1 mM) was kf increased. However, unlike the situation in hypoxic tissue, Jf was maintained at control rates. 4. In spectra obtained in the presence of low oxygen or low glucose concentrations, a resonance attributable to tissue inorganic phosphate became dectectable. This observation is discussed in terms of known changes in tissue phosphate concentrations and possible alterations in cytoplasmic pH.     

Blood glucose discrimination training in insulin-dependent diabetes mellitus (IDDM) patients

Self-management of insulin-dependent diabetes mellitus (IDDM) is dependent on a negative feedback loop of blood glucose (BG) fluctuations, which in turn directs treatment decisions to maintain normal BG. Although this feedback is typically accomplished by self-monitoring of blood glucose (SMBG), SMBG has limitations, and patients often rely on what their BG "feels" like. Two studies were performed to evaluate whether patients could learn to more accurately "feel"/discriminate their BG on the basis of internal cues or internal plus external BG cues. In Study I, BG Awareness Training significantly improved pre- to posttreatment BG estimation accuracy, relative to a control group. Study II replicated BG Awareness Training efficacy in improving BG estimation accuracy. Improvement in estimation accuracy was related only to initial accuracy; those who were initially less accurate improved the most. This improvement was represented in a 31% reduction in dangerous BG estimation errors and a 9% increase in accurate estimates. Resulting estimations were, however, still significantly less accurate than SMBG at the end of training.     

Tissue-specific variation in C4 and Slp gene regulation.

C4 and Slp are highly homologous mouse genes that differ in function and regulation. Allelic variants exist in quantitative regulation of C4 and in hormonal regulation of Slp. We have examined expression in several tissues, including liver and peritoneal macrophages which are the major sites of synthesis, using a probe that allows direct comparison of C4 and Slp mRNAs. Correctly-sized and initiated RNA, within an order of magnitude of liver levels, is found in mammary gland, lung, spleen, and kidney; lower levels are detectable in testis, brain, heart and submaxillary gland. By comparing expression in congenic mouse strains differing in C4 and Slp loci, regulation of these genes is seen to vary in different tissues. This provides a well-defined genetic system in which to examine cis-acting sequences and trans-acting factors that result in tissue-specific patterns of gene regulation.