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91.
Nibe K Kita C Morozumi M Awamura Y Tamura S Okuno S Kobayashi T Uchida K 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2007,69(10):1047-1052
Neuroaxonal dystrophy (NAD) was examined in two Papillon dogs and a mix breed dog between Papillon and Chihuahua. In addition, cerebellar cortical abiotrophy (CCA) in a Papillon dog, which had similar clinical and magnetic resonance imaging (MRI) features to those of NAD, was also investigated. The common clinical symptoms of all dogs affected with NAD and CCA, were pelvic limb ataxia and cerebellar ataxia including intention tremor, head tremor, and hypermetria in the early onset. These clinical signs were progressed rapidly, and two dogs with NAD were euthanized by owner's request and the other two died by aspiration pneumonia. MRI examinations and gross observations at necropsy revealed moderate to severe cerebellar atrophy in all cases of NAD and CCA. The most typical histological change of NAD was severe axonal degeneration with marked spheroid-formation in the dorsal horn of the spinal cords, the nuclei gracilis, cuneatus, olivalis and its circumference in the medulla oblongata. The spheroids were characterized as large eosinophilic or granular globes within the enlarged myelin sheaths, sometimes accompanied by moderate accumulation of microglias and/or macrophages. In contrast, such spheroid formation was minimal in the brain of CCA. In the cerebellum, mild to moderate loss of the Purkinje and granular cells were recognized in three dogs with NAD, whereas these changes were more prominent in a dog with CCA. Although the clinical signs and MRI findings relatively resembled between NAD and CCA, the histopathological features considered to be quite differ, suggesting distinct pathogenesis and etiology. Since both NAD and CCA are proposed as the autosomal recessive hereditary disorders, careful considerations might be needed for the breeding of Papillon and Chihuahua dogs. 相似文献
92.
Kiri Hayakawa Takayuki Sakamoto Atsushi Ishii Keita Yamaji Yoshinobu Uemoto Nanae Sasago Eiji Kobayashi Naohiko Kobayashi Tamako Matsuhashi Shin Maruyama Hirokazu Matsumoto Kenji Oyama Hideyuki Mannen Shinji Sasazaki 《Animal Science Journal》2015,86(8):737-746
The objective of the current study is to evaluate the association between fatty acid composition and fatty acid synthase gene polymorphisms as responsible mutations. For this purpose, we selected seven previously reported single nucleotide polymorphisms (SNPs) in FASN gene, including one within promoter region (g.841G>C) and six non‐synonymous SNPs (g.8805C>T, g.13126C>T, g.15532A>C, g.16024A>G, g.16039C>T, g.17924A>G), and genotyped them in Japanese Black cattle. Genotyping results revealed that g.8805 C>T and g.17924 A>G were monomorphic loci. Genome‐wide association analysis including the other five SNPs revealed that only g.841G>C showed significant associations with the percentages of C14:0, C14:1, C16:1 and C18:1 at 5% genome‐wide significance level. In order to further evaluate the effect, we genotyped g.841G>C using additional three populations, including two Japanese Black populations and a Holstein cattle population. g.16024A>G was also genotyped and included in the analysis because it has been reported to be associated with fatty acid composition in Japanese Black cattle. In the result of analysis of variance, g.841G>C showed stronger effects on fatty acid percentage than those of g.16024A>G in all populations. These results suggested that g.841G>C would be a responsible mutation for fatty acid composition and contribute to production of high‐grade beef as a selection marker in beef cattle. 相似文献
93.
Ahmed Elkhateeb Ahmed A. El-Beih Amira M. Gamal-Eldeen Montaser A. Alhammady Shinji Ohta Paul W. Paré Mohamed-Elamir F. Hegazy 《Marine drugs》2014,12(4):1977-1986
Chemical investigations of the Egyptian soft coral Sarcophyton ehrenbergi have led to the isolation of compounds 1–3 as well as the previously reported marine cembranoid diterpene sarcophine (4). Structures were elucidated by comprehensive NMR and HRMS experimentation. Isolated compounds were in vitro assayed for cytotoxic activity against human hepatocarcinoma (HepG2) and breast adenocarcinoma (MCF-7) cell lines. 相似文献
94.
松萝酸的防腐作用研究 总被引:1,自引:0,他引:1
以西藏色季拉山长松萝为材料,乙酸乙酯为溶剂回流提取制备松萝酸,并采用滤纸片法对提取物松萝酸进行了抑菌活性和最小抑制浓度测定,同时以苯甲酸为对照,研究了松萝酸的防腐作用。结果表明,松萝酸对细菌、霉菌和酵母菌的生长均有明显的抑制作用;将用松萝酸处理的鲜猪肉、豆腐和牛奶放入37℃的恒温培养箱中1周后,其菌数均不超过5×108/g(mL),而对照不低于15×10-8/g(mL)。细菌菌落数的明显减少表明,松萝酸具有一定的防腐效果;但与相同浓度的苯甲酸相比,松萝酸的抑菌防腐效果稍差。 相似文献
95.
In the field of agriculture, development of evaluation techniques for environmental changes is urgently required for the purpose of finding a balance between growth in agricultural productivity and environmental considerations. The habitat evaluation procedures (HEP) constitute one technique for habitat assessment. While HEP is widely applied to estimate both habitat quality and quantity in an environment, it appears to be necessary to develop an accurate habitat prediction model in order to evaluate environments precisely. In fact, habitat selection by fish is affected by complicated interaction between multiple environmental factors, which makes it difficult to relate physical environments to habitat preference. In the present study, we utilize artificial neural networks (ANNs), which are commonly applied to model complex systems, to predict the habitat selection of Japanese medaka (Oryzias latipes) in agricultural canals. Considering the essential vagueness of fish behavior, fuzzy membership functions are introduced into the input layer, which advances ANN to fuzzy neural network (FNN). In addition, symmetric triangular fuzzy numbers are employed to account for uncertainty in measurement errors and dispersions of physical environment. The FNN model precisely predicts the habitat preference of Japanese medaka in an agricultural canal, and the results show a good agreement between the calculated and observed habitat suitability indices (HSI). Finally, the habitat quality of two different reaches at the same point in time is compared using HEP, with a view of suitable habitat for Japanese medaka. 相似文献
96.
Shin Ugawa Muneyoshi Yamaguchi Satoru Miura Shinji Kaneko 《Soil Science and Plant Nutrition》2013,59(4):510-516
Fine root biomass can be estimated from the quantity of DNA of a target plant extracted from fine root samples using regression analysis. However, the application of this method to fine root samples mixed with soil particles (mixed samples) is difficult due to the high DNA adsorption capacity of some clay minerals. Our aim in this study was to clarify the enhancement level of the DNA extraction efficiency of an improved method, and to obtain a regression line between the amount of DNA and the root biomass from a mixed sample with similar reliability as for fine roots alone (pure root sample). We examined the amount of DNA extracted from a mixture of Zea mays L. fine roots and highly adsorbent Kanuma soil using various concentrations of a skim milk solution, which acts as an adsorption competitor for the soil particles during the DNA extraction process. The amount of DNA of Zea mays extracted from the mixed sample using 0% skim milk was lower than from the pure root sample. However, the amount of DNA extracted from the mixed sample increased with increasing concentrations of skim milk, reaching the same level as for the pure root samples and resulting in a regression line that was similar to the pure root samples. Optimal DNA extraction levels were obtained with the addition of 20?µL of a 20% skim milk solution to 30?mg of a mixed sample. We also discuss the applicability of this method to other plant species and soil types. 相似文献
97.
Nguyen Van Phi Hung Shiori Watanabe Shinji Ishikawa Norikuni Ohtake Kuni Sueyoshi Takashi Sato 《Soil Science and Plant Nutrition》2013,59(6):888-895
The quantitative analysis of the initial transport of fixed isotope 15-nitrogen (15N) in intact nodulated soybean plants (Glycine max [L.] Merr. cv. Williams) was investigated at the vegetative stage (36 days after planting, DAP) and pod-filling stage (91 DAP) by the 15N pulse-chase experiment. The nodulated roots were exposed to N2 gas labeled with a stable isotope 15N for 1 h, followed by 0, 1, 3 and 7 h of exposure with normal air. Plant roots and shoots were separated into three sections (basal, middle and distal parts) with the same length of the main stem or primary root. Approximately 80 and 92% of fixed N was distributed in the basal part of the nodulated roots at the vegetative and pod-filling stages by the end of 1 h of 15N2 exposure, respectively. In addition, about 90% of fixed 15N was retained in the nodules and 10% was exported to root and shoot after 1 h of 15N2 exposure at 91 DAP. The percentage distribution of 15N in the nodules at the pod-filling stage decreased from 90% to 7% during the 7 h of the chase period, and increased in the roots (14%), stems (54%), leaves (12%), pods (10%) and seeds (4%). The 15N distribution was negligible in the distal root segment, suggesting that N fixation activity was negligible and recycling fixed N from the shoot to the roots was very low in the initially short time of the experiment. 相似文献
98.
Kohei Matsushita Aki Kijima Yuji Ishii Shinji Takasu Meilan Jin Ken Kuroda Hiroaki Kawaguchi Noriaki Miyoshi Takehiko Nohmi Kumiko Ogawa Takashi Umemura 《Journal of toxicologic pathology》2013,26(1):19-27
In this study, the potential for development of an animal model (GPG46) capable of rapidly detecting chemical carcinogenicity and the underlying mechanisms of action were examined in gpt delta rats using a reporter gene assay to detect mutations and a medium-term rat liver bioassay to detect tumor promotion. The tentative protocol for the GPG46 model was developed based on the results of dose-response exposure to diethylnitrosamine (DEN) and treatment with phenobarbital over time following DEN administration. Briefly, gpt delta rats were exposed to various chemicals for 4 weeks, followed by a partial hepatectomy (PH) to collect samples for an in vivo mutation assay. The mutant frequencies (MFs) of the reporter genes were examined as an indication of tumor initiation. A single intraperitoneal (ip) injection of 10 mg/kg DEN was administered to rats 18 h after the PH to initiate hepatocytes. Tumor-promoting activity was evaluated based on the development of glutathione S-transferase placental form (GST-P)-positive foci at week 10. The genotoxic carcinogens 2-acetylaminofluorene (2-AAF), 2-amino-3-methylimidazo [4,5-f] quinolone (IQ) and safrole (SF), the non-genotoxic carcinogens piperonyl butoxide (PBO) and phenytoin (PHE), the non-carcinogen acetaminophen (APAP) and the genotoxic non-hepatocarcinogen aristolochic acid (AA) were tested to validate the GPG46 model. The validation results indicate that the GPG46 model could be a powerful tool in understanding chemical carcinogenesis and provide valuable information regarding human risk hazards. 相似文献
99.
Joshua Chou Jia Hao Shinji Kuroda David Bishop Besim Ben-Nissan Bruce Milthorpe Makoto Otsuka 《Marine drugs》2013,11(12):5148-5158
Foraminifera carbonate exoskeleton was hydrothermally converted to biocompatible and biodegradable zinc-tricalcium phosphate (Zn-TCP) as an alternative biomimetic material for bone fracture repair. Zn-TCP samples implanted in a rat tibial defect model for eight weeks were compared with unfilled defect and beta-tricalcium phosphate showing accelerated bone regeneration compared with the control groups, with statistically significant bone mineral density and bone mineral content growth. CT images of the defect showed restoration of cancellous bone in Zn-TCP and only minimal growth in control group. Histological slices reveal bone in-growth within the pores and porous chamber of the material detailing good bone-material integration with the presence of blood vessels. These results exhibit the future potential of biomimetic Zn-TCP as bone grafts for bone fracture repair. 相似文献
100.
Naoaki Tsutsui Tsuyoshi Ohira Tomoyuki Okutsu Junpei Shinji Sun-Hye Bae Bong Jung Kang Marcy N. Wilder 《Fisheries Science》2013,79(3):357-365
The cDNA encoding a precursor of Liv-SGP-G, the most abundant crustacean hyperglycemic hormone-family peptide in the sinus gland of the whiteleg shrimp Litopenaeus vannamei, was cloned by RT-PCR coupled with 5′- and 3′-RACE. The determined cDNA sequence consisted of 621 nucleotides comprising a 69-bp 5′-untranslated region, a 357-bp open reading frame, and a 195-bp 3′-untranslated region. The deduced sequence of 72 amino acid residues corresponding to mature Liv-SGP-G was completely identical to that of natural Liv-SGP-G, determined in our previous study. The recombinant Liv-SGP-G was thereafter heterologously expressed in Escherichia coli, and its vitellogenesis-inhibiting activity in ex vivo cultured ovarian fragments was examined. The recombinant peptides inhibited vitellogenin gene expression with almost the same efficacy as that of natural Liv-SGP-G purified from sinus glands. 相似文献