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31.
From April 1999 to December 2000, a survey was made on the distribution of Staphylococcus species on the skin of 7 kinds of animals and humans. Staphylococci were isolated from 12 (100%) of 12 pigs, 17 (89.5%) of 19 horses, 30 (100%) of 30 cows, 73 (90.1%) of 81 chickens, 10 (40%) of 25 dogs, 23 (76.7%) of 30 laboratory mice, 20 (52.6%) of 38 pigeons, and 80 (88.9%) of 90 human beings. The predominant staphylococci isolated from a variety of animal species were novobiocin-resistant species, S. xylosus and S. sciuri regardless of the animal host species. The novobiocin-resistant species including S. xylosus and S. sciuri were only occasionally isolated from human skin. The predominant staphylococci found on human skin were novobiocin-sensitive species, S. epidermidis (63.8%), followed by S. warneri (28.8%) and S. hominis (13.8%). The results suggest that the staphylococcal flora inhabiting animal skin are different from those of human skin in regard to the predominant species isolated. In this study, we used pulsed-field gel electrophoresis to examine the chromosomal polymorphisms of S. epidermidis isolated most frequently from human skin. Strains of S. epidermidis showed the greatest genomic diversity in their fragment patterns.  相似文献   
32.
The prevalence of staphylococci that harbor the mecA gene responsible for methicillin resistance was examined in healthy breeding mares. Staphylococci often cause diseases of horses such as metritis, keratitis, and abscess. Methicillin-resistant staphylococci would make antibiotic treatments ineffective, so it may be significant to know the distribution of mecA-harboring staphylococci in mares. Isolation of mecA-harboring staphylococci was achieved from nares and pasterns of 100 mares in Hokkaido, Japan. From 13% of the mares, mecA-harboring staphylococci, including 15 isolates of Staphylococcus sciuri and 3 of Staphylococcus lentus, were isolated. Isolates of S. sciuri were found to be genetically polyclonal by pulsed-field gel electrophoresis. These isolates produced no PCase and showed low or no resistance to beta-lactam and other classes of antibiotics. Distribution of staphylococcal species and levels of antibiotic resistance were found to be different between isolates from the present mares and those previously reported from riding-horses. Antibiotic pressure may lead to these differences. In addition, it appears that mecA-harboring S. sciuri may be native to horses.  相似文献   
33.
Granulocyte macrophage-colony stimulating factor (GM-CSF) increases ovine interferon-tau (oIFNtau) secretion by ovine conceptuses, but endometrial production of GM-CSF has not been characterized. Endometrial GM-CSF expression was evaluated in ovariectomized ewes implanted with estradiol-17beta (E(2)) and/or progesterone (P(4)) for 14 days, in day 14 cyclic and day 14 pregnant ewes. Relative levels of endometrial GM-CSF mRNA were 3-fold higher in E(2)- and E(2)/P(4)-treated ewes than that of control or P(4)-treated ovariectomized ewes. Levels of endometrial GM-CSF mRNA for cyclic ewes were similar to E(2)- and E(2)/P(4)-treated ewes, but amounts of GM-CSF mRNA in pregnant ewes were 2-fold higher. GM-CSF concentrations in endometrial culture media, determined by GM-CSF bioassay, for cyclic and E(2)/P(4)-treated ovariectomized ewes were 3-fold higher than those of control, E(2)- and P(4)-treated ovariectomized ewes; however, amounts of GM-CSF in pregnant ewes were 2-fold higher. Immunoreactive GM-CSF, examined by western blot, was detected in the culture medium from E(2)/P(4)-treated ovariectomized, cyclic and pregnant ewes. Luminal and glandular epithelia and stromal regions were determined to be sites of GM-CSF expression by immunohistochemistry and in situ hybridization techniques. Data indicate that combined E(2) and P(4) treatment of ovariectomized ewes is sufficient to restore GM-CSF expression to the level found in cyclic ewes; however, GM-CSF mRNA and protein in pregnant ewes is 2-fold greater than in ovariectomized or cyclic ewes. These data suggest that the conceptus, in addition to steroids, may play a role in the regulation of endometrial production of GM-CSF.  相似文献   
34.
Male F344 rats received diet containing 3,000 ppm 2,6-dimethylaniline (DMA) after initiation with a single subcutaneous injection of 2,400 mg/kg of N-bis(2-hydroxypropyl)nitrosamine (DHPN), and histological and electron microscopic examinations of the nasal cavity were performed at 4, 13, 26 and 52 weeks to examine sequential changes induced by DMA. Severe atrophy of Bowman's glands and epithelial disarrangement were apparent from week 4, followed by dilatation and/or proliferation of Bowman's glands, degeneration of epithelial cells, and proliferation of undifferentiated epithelial cells from week 13. Focal glandular hyperplasias, dysplastic foci, and adenomas were observed from week 26, and carcinomas at 52 week. These nasal lesions were mostly evident in the olfactory mucosa in the nasal cavity, and their severity and/or incidences, other than atrophy of Bowman's glands, increased with the treatment period. Electron microscopically, carcinoma cells demonstrated desmosomes, dense secretory granules identical to those in normal Bowman's glands, a basement membrane, and microvilli. These results suggest that Bowman's glands are the target of DMA, giving rise to nasal carcinomas after DHPN-initiation.  相似文献   
35.
A new candidate systemic rice blasticide, SSF126, dose-dependently inhibited NADH oxidation by submitochondrial particles from rice roots. However, oxidation by the root submitochondrial particles was much less susceptible to SSF126 compared to that by submitochondrial particles from mycelial cells ofPyricularia grisea, a pathogen causing rice blast. Interestingly, SSF126 did not completely suppress the respiration by intact rice roots, and the respiratory activity of the roots recovered from inhibition time-dependently even in the presence of SSF126 at concentrations sufficient to fully block oxidation by the submitochondrial particles. This recovery was not due to selective extrusion of SSF126 from the roots, but to switching from the cytochrome pathway to the alternative cyanide-resistant respiratory pathway. In immunoblots of the alternative oxidase, high molecular mass species were detected in the mitochondria from rice roots in addition to low molecular mass species. Quantification of high and low molecular mass species revealed an increase in the amount of a protein corresponding to a 36-kDa species equivalent to a decrease in the amount of a protein corresponding to a 72-kDa species following a 5-h incubation with SSF126. This conversion of the alternative oxidase to the low molecular mass species in the mitochondria was correlated with the respiratory recovery found in intact rice roots, suggesting that the low molecular mass species is the active form of the alternative oxidase and the high molecular mass species is the inactive form. These results suggest that rice plants can block the severe injury caused by limiting the cytochrome pathway by SSF126 through utilization of the alternative pathway promoted by the interconversion of the alternative oxidase protein.  相似文献   
36.
1. Changes in plasma alpha1-acid glycoprotein (AGP) concentration and immune responses following Escherichia coli lipopolysaccharide (LPS) injection were studied in broiler chickens. 2. Higher plasma AGP concentrations were observed from 12 to 48 h after a single injection of LPS. 3. The highest concentration of plasma AGP was observed on day 2 followed by a gradual decrease in chicks injected with 150 mug/kg body weight of LPS every day for 13 d. 4. Plasma AGP concentration in chicks injected daily with LPS at 900 mug/kg body weight for 13 d increased on day 2, and decreased on day 4 to the concentration found before the injection. The concentration increased again on day 10. 5. Changes in plasma interleukin-1 (IL-1) like activity were similar to those in plasma AGP concentration when LPS was injected daily at 900 mug/kg body weight for 3 d. 6. Responses of blood mononuclear cell (MNC) proliferation to mitogen or concanavalin A, (Con A), and pokeweed mitogen (PWM) were positively correlated with changes in plasma AGP concentration. 7. The results suggest that plasma AGP concentration could be used as a positive indicator of changes in blood MNC proliferation to a mitogen and in plasma IL-1 like activity.  相似文献   
37.
ABSTRACT:   Gnomefish Scombrops boops and Scombrops gilberti are commercially important fishes in Japan, but these species are often confused in the markets because of their morphological similarity. To identify these two species, we performed nucleotide sequencing and restriction fragment length polymorphism (RFLP) analysis on 16S ribosomal RNA (rRNA) gene and the control region in mitochondrial DNA. Five and 12 nucleotide substitutions were observed between species in the 777-bp 16S rRNA gene and 471-bp control region, respectively. Diagnostic restriction sites for discriminating between S. boops and S. gilberti were found in the 16S rRNA gene, but not in the control region. Polymerase chain reaction (PCR)–RFLP analysis using two enzymes, Eco NI and Mva I, clearly discriminated between S. boops and S. gilberti identified by meristic characters. The PCR–RFLP analysis identified most of the 168 Scombrops young caught in the coastal waters of the Izu and Miura peninsulas as S. boops , suggesting that S. gilberti juveniles are rare in this area.  相似文献   
38.
In evergreen azaleas, major anthocyanins were detected from petals of wild species and cultivars by HPLC analysis. Depending on flower color, all samples were divided into three groups: red, purple or white, using the Japan color standard for horticultural plants. The chromatic components a* and b* values of red group samples showed a convergent distribution, whereas those of purple group samples showed a wider distribution. According to the HPLC analysis, red group samples had two to four major anthocyanins, and those of the purple group had two to six major ones. In contrast, no anthocyanins were detected in the white group petals, although anthocyanidins were detected. These results suggest that the anthocyanin constitution of the purple group flowers is more varied than that of the red group flowers, and this wider variety among purple flowers contributes to extending the diversity of flower color in evergreen azalea.  相似文献   
39.
An indirect hemagglutination (IHA) test using sonicated extract as the antigen was developed for the detection of antibodies to Clostridium chauvoei. This antigen can be adsorbed onto glutaraldehyde-fixed sheep red blood cells treated with tannic acid and can be destroyed by trypsin and heat treatment. It corresponded well with the flagella of the organism, when analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and the gel diffusion test. No serological cross-reactivity was found in the IHA test when the antigen was tested against 4 species of clostridial antibodies. Our results suggest that the IHA test mainly detects antibodies against the flagella of C. chauvoei.  相似文献   
40.
ABSTRACT:   The complete cDNA sequences encoding predominant types of myosin heavy chain (MYH) in the fast skeletal muscle were determined for brushtooth lizardfish Saurida undosquamis and wanieso lizardfish S. wanieso , which are used as materials for preparing high-quality surimi-based products. The cDNA consisted of 5973 and 5987 bp, respectively, and both encompassed an open reading frame encoding a polypeptide of 1936 amino acid residues. Brushtooth and wanieso lizardfish MYH showed the amino acid sequence identity of 92–93% to white croaker MYH, which was higher than that of 90% to walleye pollack MYH. The putative binding sites for ATP, actin, and regulatory and essential light chains in the subfragment-1 region of brushtooth lizardfish MYH exhibited a high identity with white croaker counterparts as well as the sequences of subfragment-2 and light meromyosin. In contrast, phylogenetic tree, constructed by the neighbor-joining method based on mitochondrial 16S rRNA gene, revealed that the two lizardfish species formed a cluster with walleye pollack, which was paraphyletic with white croaker. Therefore, a good reputation for lizardfish and white croaker to have a high thermal-gel forming ability seemed to be reflected by MYH rather than biological similarity as revealed by the mitochondrial 16S rRNA gene.  相似文献   
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