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71.
Nobukazu SAISHU Kazutaka MORIMOTO Hiroshi YAMASATO Hiroichi OZAKI Toshiyuki MURASE 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(9):1037-1042
Thirty-eight Aerococcus viridans isolates were obtained from milk from
478 cows with clinical mastitis in a farm during the periods between November 2011 and
February 2012, and between December 2012 and March 2013. Additional isolates were obtained
from processed manure (a mixture of composted manure, straw and hydrated lime) and bedding
materials. The processed manure was later used to cover the floor of the stalls in barns
as bedding materials. The temperatures recorded in the composted and processed manure were
not as high as those generally observed during satisfactory composting. To reveal the
association of A. viridans in manure-related products with intramammary
infection in cows, isolates were characterized by their DNA fragment patterns as
determined by pulsed-field gel electrophoresis (PFGE) and antimicrobial susceptibility
testing. Isolates obtained from milk, processed manure and bedding materials had identical
DNA fragment patterns. Antimicrobial susceptibilities were determined for 29 isolates from
milk, processed manure and bedding materials. Of these, 26 (89.7%) were resistant to
clindamycin, whereas virtually all the isolates were susceptible to 12 other
antimicrobials including cefalosporins that have been used to treat bovine mastitis in
Japan. In vitro, three A. viridans isolates from milk
and an isolate from processed manure survived for 3 hr in Good’s buffer (pH 9) at high
temperature (50°C). The results suggest that the processed manure and bedding materials in
this farm were possible sources of A. viridans that caused infection in
the cows with mastitis. 相似文献
72.
Weak activity of UDP-glucuronosyltransferase toward Bisphenol analogs in
mouse perinatal development
Risa YABUSAKI Hidetomo IWANO Sumito TSUSHIMA Nanako KOIKE Naoko OHTANI Kentaro TANEMURA Hiroki INOUE Hiroshi YOKOTA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(11):1479-1484
Bisphenol A (BPA) is a widely used industrial chemical that disrupts endocrine function.
BPA is an endocrine disrupting chemical (EDC) that has been demonstrated to affect
reproductive organ development, brain development, metabolic disease and post-natal
behavior. Accordingly, Bisphenol analogs, Bisphenol F (BPF, bis (4-hydroxyphenyl) methane)
and Bisphenol AF (BPAF, 4,4-hexafluoroisopropylidene) diphenol) are used as replacements
for BPA. BPA is mainly metabolized by UDP-glucuronosyltransferase (UGT), UGT2B1, but this
effective metabolizing system is weak in the fetus. In the present study, we demonstrated
that hepatic UGT activity toward BPAF was very weak, in comparison with BPA and BPF, in
the fetus, pups and dams. Conversely, hepatic UGT activity toward BPF was very weak in the
fetus and newborn pups, and was increased to the same level as BPA post-partum. In
conclusion, BPAF possibly tends to accumulate in the fetus, because of weak metabolism
during the perinatal period, suggesting that the metabolism of individual Bisphenol
analogs requires assessment to properly gauge their risks. 相似文献
73.
Hiroshi ISEKI Michihiro TAKAGI Kenji KAWASHIMA Tomoyuki SHIBAHARA Yoshiko KURODA Hiroshi TSUNEMITSU Makoto YAMAKAWA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(12):1663-1666
To clarify the pathogenicity of Japanese type 1 porcine reproductive and respiratory
syndrome virus (PRRSV) isolate in experimentally infected pigs, we evaluated clinical
signs and monitored viremia for 21 days post-inoculation (dpi). Lungs were mottled, tanned
and reddish in appearance; had lesions predominantly in the cranial, middle and accessory
lobes; and failed to collapse at 10 dpi. Although microscopic lesions of lungs were
reproduced using the Japanese emerging type 1 PRRSV isolate under experimental conditions,
no significant differences were noted between the challenge and control groups regarding
mean rectal temperature and daily weight gain. These results provide useful insights into
the limited pathogenicity of single infection with the Japanese type 1 PRRSV isolate in
piglets, which differ from findings in reported field cases. 相似文献
74.
Kazumi KISHIDA Mitsuhiro SAKASE Kenta MINAMI Miyuki M. ARAI Reiko SYOJI Namiko KOHAMA Takayuki AKIYAMA Akio OKA Hiroshi HARAYAMA Moriyuki FUKUSHIMA 《The Journal of reproduction and development》2015,61(6):519-524
The purposes of this study were to examine the relationship between male artificial insemination (AI)
fertility and sperm acrosomal conditions assessed by new and conventional staining techniques and to identify
possible reproductive dysfunctions causing low conception rates in AI using frozen-thawed spermatozoa with
poor acrosomal conditions in Japanese Black bulls. We investigated individual differences among bulls in the
results concerning (1) acrosomal conditions of frozen-thawed spermatozoa as assessed by not merely peanut
agglutinin-lectin staining (a conventional staining technique) but also immunostaining of acrosomal
tyrosine-phosphorylated proteins (a new staining technique), (2) routine AI using frozen-thawed spermatozoa as
assessed by pregnancy diagnosis, (3) in vivo fertilization of frozen-thawed spermatozoa and
early development of fertilized eggs as assessed by superovulation/AI-embryo collection tests and (4)
in vitro fertilization of frozen-thawed spermatozoa with oocytes. The percentages of
frozen-thawed spermatozoa with normal acrosomal conditions assessed by the abovementioned staining techniques
were significantly correlated with the conception rates of routine AI, rates of transferable embryos in
superovulation/AI-embryo collection tests and in vitro fertilization rates. These results are
consistent with new suggestions that the distribution of acrosomal tyrosine-phosphorylated proteins as well as
the acrosomal morphology of frozen-thawed spermatozoa are AI fertility-associated markers that are valid for
the prediction of AI results and that low conception rates in AI using frozen-thawed spermatozoa with poor
acrosomal conditions result from reproductive dysfunctions in the processes between sperm insemination into
females and early embryo development, probably failed fertilization of frozen-thawed spermatozoa with
oocytes. 相似文献
75.
76.
Mitigation of nitrous oxide (N2O) emission from swine wastewater treatment in an aerobic bioreactor packed with carbon fibers 下载免费PDF全文
Takahiro Yamashita Ryoko Yamamoto‐Ikemoto Hiroshi Yokoyama Hirofumi Kawahara Akifumi Ogino Takashi Osada 《Animal Science Journal》2015,86(3):358-368
Mitigation of nitrous oxide (N2O) emission from swine wastewater treatment was demonstrated in an aerobic bioreactor packed with carbon fibers (CF reactor). The CF reactor had a demonstrated advantage in mitigating N2O emission and avoiding NOx (NO3 + NO2) accumulation. The N2O emission factor was 0.0003 g N2O‐N/gTN‐load in the CF bioreactor compared to 0.03 gN2O‐N/gTN‐load in an activated sludge reactor (AS reactor). N2O and CH4 emissions from the CF reactor were 42 g‐CO2 eq/m3/day, while those from the AS reactor were 725 g‐CO2 eq/m3/day. The dissolved inorganic nitrogen (DIN) in the CF reactor removed an average of 156 mg/L of the NH4‐N, and accumulated an average of 14 mg/L of the NO3‐N. In contrast, the DIN in the AS reactor removed an average 144 mg/L of the NH4‐N and accumulated an average 183 mg/L of the NO3‐N. NO2‐N was almost undetectable in both reactors. 相似文献
77.
Fujii H Nakagawa T Nishioka H Sato E Hirose A Ueno Y Sun B Yokozawa T Nonaka G 《Journal of agricultural and food chemistry》2007,55(4):1525-1531
Controlled acid-catalyzed degradation of proanthocyanidin polymers in grape seeds together with L-cysteine led to oligomeric proanthocyanidin-L-cysteine complexes along with monomeric flavan-3-ol derivatives being isolated, and their structures were confirmed on the basis of spectroscopic data and by chemical means. In addition, comparative studies on the antioxidative and survival effects of oligomeric proanthocyanidin-L-cysteine complexes and proanthocyanidin polymers were performed. The oligomeric proanthocyanidin-L-cysteine complexes showed higher bioavailability and antioxidant capacity and enhanced survival time in the animal test groups. In addition, it is suggested that the oligomeric complexes may help to prevent oxidative stress and may reduce free radical production. 相似文献
78.
Taguchi H Watanabe S Hirao T Akiyama H Sakai S Watanabe T Matsuda R Urisu A Maitani T 《Journal of agricultural and food chemistry》2007,55(5):1649-1655
Kiwifruit (Actinidia deliciosa and Actinidia chinensis) is allergenic to sensitive patients, and, under Japanese regulations, it is one of the food items that are recommended to be declared on food labeling as much as possible. To develop PCR-based methods for the detection of trace amounts of kiwifruit in foods, two primer pairs targeting the ITS-1 region of the Actinidia spp. were designed using PCR simulation software. On the basis of the known distribution of a major kiwifruit allergen (actinidin) within the Actinidia spp., as well as of reports on clinical and immunological cross-reactivities, one of the primer pairs was designed to detect all Actinidia spp. and the other to detect commercially grown Actinidia spp. (i.e., kiwifruit, Actinidia arguta, and their interspecific hybrids) except for Actinidia polygama. The specificity of the developed methods using the designed primer pairs was verified by performing PCR experiments on 8 Actinidia spp. and 26 other plants including fruits. The methods were considered to be specific enough to yield target-size products only from the target Actinidia spp. and to detect no target-size products from nontarget species. The methods were sensitive enough to detect 5-50 fg of Actinidia spp. DNA spiked in 50 ng of salmon testis DNA used as a carrier (1-10 ppm of kiwifruit DNA) and 1700 ppm (w/w) of fresh kiwifruit puree spiked in a commercial plain yogurt (corresponding to ca. 10 ppm of kiwifruit protein). These methods would be expected to be useful in the detection of hidden kiwifruit and its related species in processed foods. 相似文献
79.
Arnil C. Emata Hiroshi Y. Ogata Esteban S. Garibay Hirofumi Furuita 《Fish physiology and biochemistry》2003,28(1-4):489-491
Mangrove red snapper fed advanced broodstock diets containing squid meal and squid oil exhibited higher hatching rates, cumulative survival and survival activity index than those fed a basal diet or a basal diet supplemented with mixture of antioxidants. On the other hand, fatty acid analyses of ovaries and fry of wild fish and eggs and larvae of broodstock fed raw fish revealed high arachidonic acid (ARA) and docosahexaenoic acid (DHA) levels and relatively lower eicosapentaenoic acid (EPA) levels consequently showing high ARA/EPA and DHA/EPA ratios compared to cold water species. This suggests that ARA may be nutritionally more important for egg and larval development and survival in tropical marine fish and its supplementation in broodstock diets may enhance reproductive performance of mangrove red snapper. 相似文献
80.
The duality of teleost gonadotropins 总被引:5,自引:0,他引:5
Hiroshi Kawauchi Kunimasa Suzuki Hiromichi Itoh Penny Swanson Nobuko Naito Yoshitaka Nagahama Masumi Nozaki Yasumitu Nakai Seiga Itoh 《Fish physiology and biochemistry》1989,7(1-6):29-38
The duality of salmon gonadotropins has been proved by biochemical, biological, and immunological characterization of two
chemically distinc gonadotropins. GTH I and GTH II were equipotent in stimulating estradiol production, whereas GTH II appears
to be more potent in stimulating maturational steroid synthesis. The ratio of plasma levels and pituitary contents of GTHs
and the secretory control by a GnRH suggest that GTH I is the predominant GTH during vitellogenesis and early stages of spermatogenesis
in salmonids, whereas GTH II is predominant at the time of spermiation and ovulation. GTH I and GTH II are found in distinctly
separate cells. In trout, GTH I is expressed first in ontogeny, whereas GTH II cells appear coincident with the onset of spermatogenesis
and vitellogenesis, and increase dramatically at the time of final reproductive maturation. Comparison of the amino acid sequences
of polypeptides and the base sequences of cDNA revealed that salmon GTH I β is more similar to bovine FSHβ than bovine LHβ
and salmon GTH II β shows higher homology to bovine LHβ than to bovine FSHβ. The existence of two pituitary gonadotropins
in teleosts as well as tetrapods suggests that the divergence of the GTH gene took place earlier than the time of divergence
of teleosts from the main line of evolution leading to tetrapods. 相似文献