The therapeutic effect of cortisone,somatotrophic hormone,and hesperedin methyl chalcone in suppressing experimental moniliasis in mice

Summary Female mice infected with moniliasis and treated with a mixture of cortisone, somatotrophic hormone, and hesperedin methyl chalcone showed a marked reduction in the severity of the infection; male mice similarly infected and treated were apparently unaffected. Factors such as the severity of the infection, sex of the animal, and particular doses and proportions used in influencing the response of the infected animal to this mixture are discussed.This paper is part of a study supported by Contract No. NONR 717(00) between the Office of Naval Research, Department of the Navy, and The Creighton University.A preliminary report of this study was presented before the 64th annual meeting of the Nebraska Academy of Sciences (Scherr, 1954b).     

Population genetic structure and the effect of founder events on the genetic variability of moose, Alces alces, in Canada

Moose, Alces alces, occur naturally throughout most of Canada but successful introductions of known numbers of animals have been made to the islands of Newfoundland and Cape Breton. Five microsatellite loci were used to investigate the population genetic structure and any change in genetic variability due to founder events of moose in Canada. Comparisons of allele frequencies for moose from 11 regions of the country suggested that there are at least seven genetically distinct populations (P < 0.05) in North America, namely Alberta, eastern Ontario, New Brunswick, Cape Breton, Labrador, western Newfoundland, and the Avalon Peninsula of Newfoundland. The average population heterozygosity was approximately 33% (range from 22 to 41%). UPGMA analysis of Nei's genetic distances produced phenograms similar to what would be expected when geographical location and population history are considered. The loss of heterozygosity due to a single founder event (n = 3; two introductions and a natural colonization) ranged from 14 to 30%, and the cumulative loss of heterozygosity due to two successive founder events (an introduction followed by a natural colonization) was 46%. In these examples loss of genetic variability has not been associated with any known phenotypic deviances, suggesting that populations may be established from a small number of founders. However, the viability of these founded populations over evolutionary timescales cannot be determined and is highly dependent upon chance.     

Thrombin induces proteinase-activated receptor-1 gene expression in endothelial cells via activation of Gi-linked Ras/mitogen-activated protein kinase pathway

We addressed the mechanisms of restoration of cell surface proteinase-activated receptor-1 (PAR-1) by investigating thrombin-activated signaling pathways involved in PAR-1 re-expression in endothelial cells. Exposure of endothelial cells transfected with PAR-1 promoter-luciferase reporter construct to either thrombin or PAR-1 activating peptide increased the steady-state PAR-1 mRNA and reporter activity, respectively. Pretreatment of reporter-transfected endothelial cells with pertussis toxin or co-expression of a minigene encoding 11-amino acid sequence of COOH-terminal Galphai prevented the thrombin-induced increase in reporter activity. Pertussis toxin treatment also prevented thrombin-induced MAPK phosphorylation, indicating a role of Galphai in activating the downstream MAPK pathway. Expression of constitutively active Galphai2 mutant or Gbeta1gamma2 subunits increased reporter activity 3-4-fold in the absence of thrombin stimulation. Co-expression of dominant negative mutants of either Ras or MEK1 with the reporter construct inhibited the thrombin-induced PAR-1 expression, whereas constitutively active forms of either Ras or MEK1 activated PAR-1 expression in the absence of thrombin stimulation. Expression of dominant negative Src kinase or inhibitors of phosphoinositide 3-kinase also prevented the MAPK activation and PAR-1 expression. We conclude that thrombin-induced activation of PAR-1 mediates PAR-1 expression by signaling through Gi1/2 coupled to Src and phosphoinositide 3-kinase, and thereby activating the downstream Ras/MAPK cascade.     

Ploidy and strain differences in seed germination of Glycine wightii at different pH levels

Summary Seeds from 27 wild strains (18 tetraploids and 9 diploids) of Glycine weightii were germinated at a pH range of 5 to 8. The differences in germination (%) between all the strains were highly significant but between pH levels they were only nearly significant (P=0.067) with no interaction between pH levels and strains. Mean germination (%) for all tetraploids seems to be slightly higher ( 2%) than that for all diploids, especially at pH's 5, 7 and 8 but this may be due to the significantly longer time ( one day) it took tetraploids to complete germination. The apparent inverse relationship between seed weight and germination (%) was not significant.Mean germination time was highly significant for strains, pH's and their interaction. Increasing mean germination (%) resulted in decreasing mean germination time among strains. Large seeds took less time to germinate especially those from some of the tetraploid strains. This indicates that it is possible to produce a variety with high germination (%), fast germination rate and possibly large seeds. If the marked difference in pH tolerance among strains will prove to be mainly hereditary, then it will be also possible to select for either specific pH tolerance or tolerance at a wide range of pH.     

Determinants of peak muscle power: effects of age and physical conditioning

The relationships between absolute peak muscle power (W _peak), muscle cross sectional area (CSA_tot, i.e. the sum of both thigh and calf CSA) and muscle high energy phosphate concentration (adenosine 5-triphosphate [ATP] and phosphocreatine concentrations [PC]) were studied in 47 subjects classified into five groups: A, 10 sedentary (S) subjects aged 20–35 years; B, 9 S aged 35–50 years; C, 9 S aged more than 50 years; D, 13 children aged 8–13 years; and E, 6 athletes (top level volleyball players) aged 24 (SD 3) years. The W _peak was measured during a maximal vertical high jump off both feet on a force platform. The CSA_tot was measured anthropometrically. The [ATP] and [PC] were determined by ³¹Phosphorus nuclear magnetic resonance spectroscopy. The W _peak decreased with age, was 65% lower in D than in A, and 43% higher in E than in A. The CSA_tot did not vary with age, was 45% smaller in D than in A, and 15% greater in E than in A. The [ATP] and [PC] were essentially the same in all groups. The changes observed in W _peak were only partially accounted for by changes in CSA_tot. Therefore, in addition to the variables investigated, other factors appear to have been involved in the determination of W _peak with increasing age and training. An important role may be played by hormonal, particularly at puberty, and neural factors.     

RELATIONSHIPS AMONG MORPHOLOGICAL STATUS, STEROID HORMONES, AND POST-THAWING VIABILITY OF FROZEN SPERMATOZOA OF MALE MINKE WHALES (BALAENOPTERA ACUTOROSTRATA)

Spermatozoa from 21 mature minke whales ( Balaenoptera acutorostrata ) taken in the Antarctic Ocean for Japanese research were recovered from vasa deferentia, diluted 1:9 in a Tris-based diluent, and frozen at - 80°C on board the vessel. After a period ranging from 45 to 125 d, the samples were transferred to liquid nitrogen and transported to the laboratory. After thawing at 37°C the motility (percentage of motile spermatozoa), vitality (proportion of live spermatozoa), and sperm concentration were determined for each sample. These values were tested for correlations with morphological measurements (body size, body weight, testis weight) and serum concentrations of progesterone (Pd), estradiol-17β (E2), and testosterone (T). Ten of 21 samples had motile spermatozoa (2%-40%). Although no motile spermatozoa were observed in 1.1 samples, all sperm samples were examined by eosinnigrosin staining and showed vitality levels of 3%44%. It was found that the motility (Y = 0.54) and vitality (r = 0.53) of the spermatozoa were significantly (P < 0.01) correlated with the E₂ levels (8.50 ± 1.80 pg/ml). Serum T levels (0.07 ± 0.02 ngml) were significantly correlated with the E₂ levels (r = 0.58, P < 0.01>, but sperm concentrations were not correlated with either Ea or T levels. The present study demonstrates that spermatozoa of minke whales can be successfully cryopreserved.     

Isolation and characterization of acetonitrile utilizing bacteria

Summary Bacteria utilizing high concentrations of acetonitrile as the sole carbon source were isolated and identified asChromobacterium sp. andPseudomonas aeruginosa. Maximum growth was attained after 96 h of incubation andP. aeruginosa grew slightly faster thanChromobacterium sp. The strains were able to grow and oxidize acetonitrile at concentrations as high as 600 mM. However, higher concentrations inhibited growth and oxygen uptake. Degradation studies with (¹⁴C)acetonitrile indicated 57% of acetonitrile was degraded byPseudomonas aeruginosa as compared to 43% byChromobacterium. The isolates utilized different nitrile compounds as carbon substrates.