Inhibitory Effect of Glycerin on Vibrio parahaemolyticus and Salmonella

In a study of the effect of glycerin in transport media on Vibrio parahaemolyticus and Salmonella, it was found that a concentration of 30% glycerin was highly inhibitory for V. parahaemolyticus and to a lesser degree for Salmonella. The incorporation of peptone or human feces in media did not reduce the inhibitory effect of glycerin. In media with 15% glycerin, viable counts of V. parahaemolyticus and Salmonella increased after 24 hr of incubation both in the presence and absence of feces. Due to the concurrent increase in the total bacterial count in the media containing feces, no enrichment effect was noted.     

Heritability of Eating Behavior Assessed Using the DEBQ (Dutch Eating Behavior Questionnaire) and Weight‐related Traits: The Healthy Twin Study

The heritability of eating behavior and body weight–related traits in Asian populations has not been reported. The purpose of this study was to estimate the heritability of eating behavior and the body weight–related traits of current weight and self‐reported past weight among twins and their families. Study subjects were 2,144 Korean, adult, same‐sex twins and their families at the ages between 20 and 65 years (443 monozygotic (MZ) and 124 dizygotic (DZ) twin pairs, and 1,010 individuals of their family). The Dutch Eating Behavior Questionnaire (DEBQ) was used to assess three eating behavior subscales measuring restraint, emotional eating, and external eating. A variance component approach was used to estimate heritability. After consideration of shared environmental effects and adjustment for age and sex effects, the heritability estimates ± s.e. among twins and their family members were 0.31 ± 0.036 for restraint, 0.25 ± 0.098 for emotional eating, 0.25 ± 0.060 for external eating, 0.77 ± 0.032 for measured current body weight, and 0.70 ± 0.051 for self‐reported weight at 20 years old. The three DEBQ subscales were associated with all weight related traits after adjustment for age and sex. These results suggest eating behaviors and weight‐related traits have a genetic influence, and eating behaviors are associated with obesity indexes. Our findings from Korean twin family were similar to those reported in Western populations.     

Stable ester conjugate between the Saccharomyces cerevisiae RAD6 protein and ubiquitin has no biological activity.

The RAD6 gene of Saccharomyces cerevisiae, which encodes a ubiquitin-conjugating enzyme, is required for DNA repair, DNA damage-induced mutagenesis and sporulation. To evaluate the biological relevance of the thioester adduct between RAD6 protein and ubiquitin, formed as an obligatory, transient intermediate during ubiquitin conjugation to substrates, we altered cysteine 88 in RAD6 to serine. Esterification with ubiquitin occurs at serine 88 in the mutant protein, but conjugation of ubiquitin to the test substrate histone H2A is inactivated. Phenotypically, strains harboring the rad6 Ser88 allele are indistinguishable from rad6 deletion (rad6 delta) mutant cells. These findings argue against ligation of ubiquitin at cysteine 88 acting as a functional switch of a cryptic biochemical activity in RAD6.     

Selection and proliferation of rapid growing cell lines from embryo derived cell cultures of yew tree (Taxus cuspidata Sieb. et Zucc)

Calli were induced from 300,000 embryos isolated from immature to mature stage of seeds collected on late September from 14 elite trees. When the embryos were cultured onto plastic Petri-dish containing 20 mL of modified B5 basal medium supplemented with 3% (w/v) sucrose, 500 mg/L casein hydrolysate, 250 mg/L myo-inositol, 0.5% (w/v) polyvinyl polypyrrolidon (PVPP), 2×MS vitamins, 0.5 mg/L gibberellic acid, and 10 mg/L 2,4-D after 2 weeks of culture, yellowish-white calli were immediately formed on the surfaces of embryos, and subcultured for 4 weeks in same culture medium. Because most of calli maintained for more than 3 months were revealed differences in their colors, surface texture, and growth rate, visual selection was made for first round screening. When the size of visually selected calli larger than 19 mm in their diameter were inoculated, persistent proliferation was observed. Among the plating methods tested for the selection of rapid growing cell lines at single cell and/or small cell aggregate level, 2-layer spread plating revealed as the best for single cell cloning. To enhance cell growth and maintain high rate of viability for long-term culture of yew cells in bioreactor, final cell volume less than 50% in SCV seemed to be the best. Time course study revealed that 30% of inoculum density was suitable for fed batch culture. Among the tested conditional media, the rate of 1∶2 (old medium: fresh medium) was recorded at the best for cell growth.     

Microdistribution and local dosimetry of 226Ra in trabecular bone of the beagle

Sections of lumbar vertebral bodies of young adult beagle dogs have been analyzed autoradiographically to characterize and quantify the local distribution of 226Ra by means of a scanning microscope photometer. The animals received a single injection of 355 kBq/kg body weight and were serially sacrificed at 5 to 1381 days postinjection. Hotspot concentrations decreased from about 51 kBq/g bone at 5 days to 20 kBq/g at 1381 days postinjection. The diffuse concentration changed from 8.3 to 1.9 kBq/g. The mean 226Ra concentration in the trabecular areas scanned was initially higher and at the end of the observation period lower than the average calculated for the whole lumbar vertebral column. Density and area of, and fraction of bone activity in, hotspots virtually remained constant. With time hotspots tended to become translocated into bone volume. Mean dose rates to lining cells from both hotspots and diffuse labels decreased from about 210 mGy/d at early postinjection times to 105 mGy/d. This corresponds to 2.5 to 1.1 times the average skeletal dose rate. A discussion of the level of irradiation in terms of hit frequencies shows that osteoblasts in the initial phase of hotspot formation receive about 60 hits to their nucleus for the duration of bone formation. After about 6 months, however, the 226Ra concentration in new bone and the corresponding hit frequency appears to be low enough that interference with bone formation is unlikely. Morphometric measurements showed that abnormal bone accretion and thickening of trabeculae occurred. This was interpreted as an imbalance between bone formation and resorption. Both formation and resorption seem to be substantially lowered compared to control animals.     

Triterpene glycosides from Schefflera octophylla.

In addition to 3-epi-betulinic acid, three triterpene glycosides were isolated from leaves of Schefflera octophylla. The structures of the glycosides have been determined as 28-O-[alpha-L-rhamnopyranosyl(1----4)-O-beta-D-glucopyranosyl(1----6)-be ta-D- glucopyranosides of 3 alpha-hydroxy-lup-20(29)-ene-23,28-dioic acid, 3 alpha,11 alpha- dihydroxy-lup20(29)-ene-23,28-dioic acid and 3-epi-betulinic acid by spectroscopic data and chemical transformations. The last two compounds were found for the first time in the plant kingdom.     

Regulation of protein phosphorylation in pancreatic acini by cyclic AMP-mediated secretagogues: interaction with carbamylcholine

The effects on protein phosphorylation in mouse pancreatic acini of cyclic AMP-mediated secretagogues and the Ca2+-mediated agonist carbamylcholine were compared. Under the conditions adopted for the study of protein phosphorylation, carbamylcholine (3 microM) stimulated amylase release from pancreatic acini 6-fold, whereas vasoactive intestinal polypeptide (VIP) (100 nM) and the cyclic AMP analogue 8-bromo-cyclic AMP (1 mM) caused little or no increase in secretion. However, VIP and 8-bromo-cyclic AMP, when added in combination with carbamylcholine, potentiated the stimulation of amylase release to 170-180% of that caused by carbamylcholine alone. As assessed by two-dimensional gel electrophoresis, VIP reproduced four of the ten changes in protein phosphorylation elicited by carbamylcholine, these changes being the increased phosphorylation of one soluble protein and the decreased phosphorylation of three soluble proteins. VIP enhanced the carbamylcholine-induced changes in phosphorylation for three proteins. In addition, VIP increased the phosphorylation of a unique protein of Mr 52,000 and pI 5.66 which was not affected by carbamylcholine. All of the effects on protein phosphorylation exerted by VIP in the presence or absence of carbamylcholine were mimicked by 8-bromo-cyclic AMP. Secretin also reproduced most of the changes in protein phosphorylation caused by VIP, although concentrations of secretin of at least 100-fold higher were required to elicit a maximal response. It is concluded that cyclic AMP-mediated secretagogues alter the phosphorylation of a unique protein as well as of several pancreatic proteins affected by carbamylcholine. Moreover, these effects appear to be mediated primarily by VIP-preferring receptors and may be involved in the synergistic action of VIP to promote carbamylcholine-induced amylase release.     

Membrane protein phosphorylation during stomatocyte-echinocyte transformation of human erythrocytes

The normal, discoid shape of red blood cells represents an equilibrium between two opposing factors, i.e., stomatocytic and echinocytic transformations. Most stomatocytic agents were found to be inhibitors of calmodulin, a regulator of the phosphorylation of membrane proteins. We determined whether red cell shape transformations could be caused by changes in phosphorylation of membrane proteins, specifically the cAMP-dependent phosphorylation of ankyrin and band 4.1. Red blood cells were incubated with 32P and 100 microM chlorpromazine (stomatocytic transformation) or 30 mM sodium salicylate (echinocytic transformation) for various time intervals. Ghost membrane proteins were examined by polyacrylamide gel electrophoresis and autoradiography. Spectrin (beta-chain), ankyrin, band 3, band 4.1 and 4.9 were phosphorylated. No change was found in the degree and pattern of phosphorylation after stomatocytic transformation. Salicylate caused a reversible inhibition of transmembranous phosphate transport in both directions. The results indicate that the stomatocytic transformation induced by chlorpromazine and the echinocytic transformation induced by salicylate do not involve a change in phosphorylation, but that the echinocytic transformation induced by salicylate is associated with an inhibition of transmembranous transport of phosphate. Studies with salicylate suggest that the phosphorylation sites of band 3 are found mainly on the endofacial side of the membrane.     

The kinetics of the first wave of spermatogenesis in the newborn male mouse

A combination of autoradiography and air-dried techniques was used to calculate the duration of the major meiotic stages in the first wave of spermatogenesis in the newborn mouse. The data indicated that the entry into meiosis occurred asynchronously over 2 days, and the time required for each stage and the total cycle was constant. These time intervals were nearly identical with those estimated for adult animals in the present study and by other authors.