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121.
Osumi T Kishimoto Y Kano R Maruyama H Onozaki M Makimura K Ito T Matsubara K Hasegawa A 《Veterinary microbiology》2008,131(3-4):419-423
This study is the first investigation on Japanese isolates of Prototheca zopfii from bovine mastitis and the cow-barn surroundings by molecular characterization to clarify routes of infection for bovine protothecal mastitis. We performed isolation of Prototheca from cow-barn surroundings (drinking water, sewage and feces) and milk samples from cases of bovine mastitis. Genotypes of the 32 isolates of P. zopfii from cow-barn surroundings and 67 isolates from mastitis were analyzed by genotype-specific PCR assays and restriction fragment length polymorphism (RFLP) assays. All mastitis isolates were identified as P. zopfii genotype 2. Conversely, 29 isolates from cow-barn surroundings were identified as P. zopfii genotypes 1 and 3 isolates as genotype 2, respectively. Given these results, both genotypes of P. zopfii could exist in cow-barn surroundings, but no sites were identified as frequent sources of P. zopfii genotype 2. P. zopfii isolates should thus be further explored with regard to genotype to clarify the reservoir of etiological agents in bovine Prototheca mastitis. 相似文献
122.
Aoi SUMIYOSHI Koichi KITAO Takayuki MIYAZAWA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2022,84(1):157
Foamy viruses have been isolated from various mammals and show long-term co-speciation with their hosts. However, the frequent inter-species transmission of feline foamy viruses (FFVs) from domestic cats to wild cats across genera has been reported. Because infectious molecular clones of FFVs derived from wild cats have not been available, whether there are specific characteristics enabling FFVs to adapt to the new host species is still unknown. Here, we obtained the complete genome sequences of two FFV isolates (strains NV138 and SV201) from leopard cats (Prionailurus bengalensis) in Vietnam and constructed an infectious molecular clone, named pLC960, from strain NV138. The growth kinetics of the virus derived from pLC960 were comparable to those of other FFVs derived from domestic cats. Phylogenetic analysis revealed that these two FFVs from leopard cats are clustered in the same clade as FFVs from domestic cats in Vietnam. Comparisons of the amino acid sequences of Env and Bet proteins showed more than 97% identity among samples and no specific amino acid substitutions between FFVs from domestic cats and ones from leopard cats. These results indicate the absence of genetic constraint of FFVs for interspecies transmission from domestic cats to leopard cats. 相似文献
123.
Takuro NAGAHARA Koichi OHNO Itsuma NAGAO Taisuke NAKAGAWA Yuko GOTO-KOSHINO Masaya TSUBOI James K. CHAMBERS Kazuyuki UCHIDA Hirotaka TOMIYASU Hajime TSUJIMOTO 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2022,84(1):20
Intestinal lymphangiectasia (IL) is a common complication in dogs. Since nitric oxide (NO) is known to relax the lymphatic vessel, we evaluated inducible NO synthase (iNOS) expression using immunohistochemistry in 13 dogs with lymphoplasmacytic enteritis (LPE) with or without IL. The duodenal iNOS expressing cells were significantly increased in dogs with IL-negative or IL-positive LPE dogs (P=0.025, P=0.007) compared with control dogs. However, there was no significant difference in iNOS expression between IL-positive and IL-negative tissues. Based on these results, there is no clear evidence for the NO overproduction in the pathogenesis of IL in dogs with LPE. Factors other than NO could, thus, contribute to IL in dogs with LPE. 相似文献
124.
In 1985, the government of Indonesia declared an export ban on logs in order to promote the wood processing industry within
the country. Furthermore, this policy was followed by a regulation that the concessionaires have to build their own industry,
causing a great increase in wood industry. In the early period after the log export ban, the government found it to be successful
and there were no significant problems. Unfortunately, after one decade, Indonesia’s forestry sector faced some serious problems,i.e. problems in raw material supply which was lower than the log demand level in the industry, deforestation issues, and ecological
imbalance. The main objectives of this study are to identify the effects of the log export ban and to introduce some alternate
measures. 相似文献
125.
We studied population changes of the field mouse,Apodemus speciosus Temminck, by live trapping in a mixed stand of cypress and broad-leaved trees at Tama Forest Science Garden during the period
from October 1991 to March 1994. We also used radiotelemetry to investigate acorn hoarding. The number of mice captured in
1992 was three to ten times higher than that in either 1991 or 1993. The home ranges of resident mice overlapped greatly,
but a path and differences in the vegetation structure may have affected the home range of individuals. From June 1992 to
April 1993, mice actively transported and hoarded acrons. Individuals hoarded 70% of the acorns in their home ranges within
one day after release. This species was a typical scatter-hoarder and hoarded a single acorn at each cache site. Mice buried
acrons in the soil at the first hoarding, but recovered and carried them into their nests later. Although more than 50% of
the acorns were buried 0–5 cm deep, where the condition for germination seemed to be good, mice recovered and ate all cached
acorns. Mice relocated acorns farther from the original food station as they repeated hoarding. Mice transported acorns an
average of about 15–18 m (range: 2.2–49.8 m) before they ate them. From May 1993 to March 1994, the hoarding behavior of mice
was not active. Most acorns were left at food stations or cache sites for more than three months. Acorn hoarding byA. speciosus probably contributes little to the dispersal and regeneration of acorn-producing trees in years with a high rodent density. 相似文献
126.
Koichi Yoneyama Xiaonan Xie Kaori Yoneyama Takahito Nomura Ikuo Takahashi Tadao Asami Narumi Mori Kohki Akiyama Miyuki Kusajima Hideo Nakashita 《Pest management science》2019,75(9):2353-2359
Strigolactones (SLs) are carotenoid‐derived plant secondary metabolites that play important roles in various aspects of plant growth and development as plant hormones, and in rhizosphere communications with symbiotic microbes and also root parasitic weeds. Therefore, sophisticated regulation of the biosynthesis, perception and functions of SLs is expected to promote symbiosis of beneficial microbes including arbuscular mycorrhizal (AM) fungi and also to retard parasitism by devastating root parasitic weeds. We have developed SL mimics with different skeletons, SL biosynthesis inhibitors acting at different biosynthetic steps, SL perception inhibitors that covalently bind to the SL receptor D14, and SL function inhibitors that bind to the serine residue at the catalytic site. In greenhouse pot tests, TIS108, an azole‐type SL biosynthesis inhibitor effectively reduced numbers of attached root parasites Orobanche minor and Striga hermonthica without affecting their host plants; tomato and rice, respectively. AM colonization resulted in weak but distinctly enhanced plant resistance to pathogens. SL mimics can be used to promote AM symbiosis and to reduce the application rate of systemic‐acquired resistance inducers which are generally phytotoxic to horticultural crops. © 2019 Society of Chemical Industry 相似文献
127.
Rattanatrai CHAIYASING Akihiro SUGIURA Takuro ISHIKAWA Koichi OJIMA Katsuhiko WARITA Yoshinao Z. HOSAKA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(12):1812
The purpose of this study was to elucidate the functions of estrogen and two estrogen receptors (ERs; ERα and ERβ) in the myoregeneration process and morphogenesis. Cardiotoxin (CTX) was injected into the tibialis anterior (TA) muscles of ovariectomized (OVX) mice to induce muscle injury, and subsequent myoregeneration was morphologically assessed. The diameter of regenerated myotubes in OVX mice was significantly smaller than that in intact mice at all time points of measurement. OVX mice also showed lower muscle recovery rates and slower speeds than did intact mice. ER protein levels showed a predominance of ERβ over ERα in both intact and OVX states. The ERβ level was increased significantly at 7 days after CTX injection in OVX mice and remained at a high level until 14 days. In addition, continuous administration of E2 to OVX mice in which muscle injury was induced resulted in a significantly larger diameter of regenerated myotubes than that in mice that did not receive estrogen. The results indicate that estrogen is an essential factor in the myoregeneration process since estrogen depletion delayed myoregeneration in injured muscles and administration of estrogen under the condition of a low estrogen status rescued delayed myoregeneration. The results strongly suggested that ERβ may be a factor that promotes myoregeneration more than does ERα. 相似文献
128.
Shiro KUSHIBIKI Hiroyuki SHINGU Tokushi KOMATSU Fumiaki ITOH Etsuko KASUYA Hisashi ASO Koichi HODATE 《Animal Science Journal》2006,77(6):603-612
Tumor necrosis factor (TNF)‐α is a powerful macrophage cytokine released during infection, circulating in the blood to produce diverse effects in the organism. We examined the effect of recombinant bovine TNF‐α (rbTNF‐α) administration on hormone release in dairy cows during early lactation. Twelve non‐pregnant Holstein cows were treated subcutaneously with rbTNF‐α (2.5 µg/kg) or saline twice (at 11.00 and 23.00 hours). At 11.00 hours the next day, the cows were given growth hormone‐releasing hormone (GHRH, 0.25 µg/kg), thyrotrophin‐releasing hormone (TRH, 1.0 µg/kg), thyroid‐stimulating hormone (TSH, 10 µg/kg) or adrenocorticotropic hormone (500 µg/head) via the jugular vein. In the growth hormone‐releasing hormone challenge, the plasma growth hormone concentration was lower in the rbTNF‐α group than in the control (saline) group. The growth hormone and TSH responses to TRH were also smaller in the rbTNF‐α group than in the control. The plasma prolactin response to TRH was not affected by the rbTNF‐α treatment. In the TSH challenge, the rbTNF‐α‐treated cows had lower responses, as measured by plasma triiodothyronine and thyroxine, than the control cows. The rbTNF‐α treatment produced an increase in the basal plasma cortisol level, but the cortisol response to adrenocorticotropic hormone was the same level in both groups. The plasma concentrations of TNF‐α and interleukin‐1β in the cows were elevated by the rbTNF‐α treatment. The milk yield was reduced by the rbTNF‐α administration during 4 days. These data demonstrate that TNF‐α alters the secretion of pituitary and thyroid hormones in lactating cows. This effect may contribute to the suppression of the lactogenic function of the mammary gland observed in cases of coliform mastitis with high circulating TNF‐α levels. 相似文献
129.
Shinji Yamamoto Yoshihiro Wada Yoshiharu Ishikawa Koichi Kadota 《Journal of veterinary diagnostic investigation》2007,19(4):447-450
A newborn Holstein female calf had neoplastic lesions in the skin and within the thoracic and abdominal cavities but not in the bone marrow, spleen, thymus, or most lymph nodes. Because the tumor cells were positive for CD79a (B cell marker), CD5 (B-1 cell marker) and terminal deoxynucleotidyl transferase (marker for immature lymphoid precursors), a diagnosis of precursor B-1 B cell lymphoma was made. The diagnosis was strongly supported by the fact that B-1 cells can develop in the fetus, unlike B-2 cells, which are produced after birth. The lymphoma was distinct from the typical calf form of lymphoma of B-2 cell origin, which does not express CD5 and is characterized by generalized lymphadenopathy and involvement of the bone marrow, blood and spleen. 相似文献
130.
ABSTRACT: The purpose of the present paper was to examine the size relationship between the juvenile stone flounder Platichthys bicoloratus and the bivalve Nuttallia olivacea , the siphon of which is important prey for the juvenile flounder. Juvenile stone flounder feed mainly on tips of the inhalant siphon of the bivalve. The maximum width of siphon tips in the stomach contents of age-0 fish could not reach that of age-1 fish, although the siphons in age-0 fish became larger as they grew. This size discrepancy indicated a limitation in the size of bivalves available to juveniles. The proportion of total cropping frequency for the siphon of the bivalve by juveniles was estimated according to the bivalve size class. Most bivalves that had cropped siphon tips ranged from 5 to 30 mm in shell length. The total cropping frequency per bivalve was particularly intense on bivalves of 10–25 mm shell length in spite of their small proportion of 24.9% of the total. This frequency intensity indicated that the size of bivalves with cropped siphons by juvenile stone flounder might depend on the ability of juveniles rather than the size composition of the bivalves. 相似文献