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51.
Shigeru Kitanishi Masaki Nishio Kazuhiko Uehara Rikiya Ogawa Tatsuya Yokoyama Kaneaki Edo 《Environmental Biology of Fishes》2013,96(4):567-572
In this study, the level of genetic diversity of captive populations of the itasenpara bitterling (Acheilognathus longipinnis) was assessed to obtain information useful for successful captive breeding and reintroduction; this analysis was performed using mitochondrial DNA (mtDNA) sequence data. Comparison of the captive and wild populations showed low levels of genetic diversity within the captive population and significant genetic differentiation among the captive populations and also between the wild and captive populations, suggesting at chance effect during the founding process for the captive population and a subsequent genetic drift. Therefore, for successful reintroduction, it is important that the reintroduced population reflects all the genetic diversity available from the captive populations, and that releasing a large number of individuals that consist of all captive populations. 相似文献
52.
Yukihiko Hayashi Moto Kitayaki Kayoko Takezaki Hidekazu Ikeuchi Shigeru Kunugi 《Biocatalysis and Biotransformation》2013,31(1):25-31
The contribution of three exoglucanases from a commercial Trichoderma viride cellulase to transcellobiosylation, and the tolerance of these enzymes to acetonitrile co-solvent were studied. The enzymatic reactions were performed with p-nitrophenyl-β-d-cellobioside as the starting substrate. Among these enzymes, the least anionic exoglucanase (Exo I) showed the highest transcellobiosylation activity and acetonitrile tolerance. Exo I retained considerable activity even in 30% MeCN/water and produced p-nitrophenyl-β-d-cellotetraoside at about 1.5% conversion from the initial substrate in 30% MeCN/water. The residual activity of Exo I after incubation in MeCN/water mixture was almost identical to that of the crude cellulase and a considerable amount of the transcellobiosylation properties of the crude cellulase seemed to be attributable to this Exo I component. 相似文献
53.
Yoritaka Aoyama Eri Ohmura Akira Yoshida 《Bioscience, biotechnology, and biochemistry》2013,77(11):3125-3131
The effects of dietary composition on lipids in serum and in liver of rats fed with a cystine- excess diet were investigated.When starch was used as the carbohydrate source, the addition of excess-cystine caused an increase in serum cholesterol and phospholipids, and hepatomegaly. Phospholipids in serum of rats fed with a cystine-excess diet containing 5% corn oil were higher than those with a cystine-excess diet that was low in corn oil (0.1 %). The addition of konjac mannan and pectin prevented hypercholesterolemia, and the rise in phospholipids in serum was prevented by the addition of konjac mannan.Liver cholesterol (mg/liver/100 g of body wt.) increased in rats fed with a cystine-excess diet.The addition of excess cystine to a diet containing sucrose as the carbohydrate source resulted in a marked increase of cholesterol in serum and liver, and a decrease of serum triglycerides.The replacement of starch by sucrose in the cystine-excess diet increased liver cholesterol.Lipids, cholesterol, phospholipids and triglycerides in the liver, but not phospholipids, when expressed as mg per g of liver for rats fed with the diets containing sucrose, increased when compared to those for rats fed with the diets containing starch. In contrast, serum triglycerides increased. 相似文献
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Growth of Brevibacterium flavum FA-1-30 and FA-3-115, L-lysine producers derived from Br. flavum No. 2247 as S-(2-aminoethyl)-L-cysteine (AEC) resistant mutants, was inhibited by α-amino-β-hydroxyvaleric acid (AHV), and this inhibition was reversed by L-threonine. All the tested AHV resistant mutants derived from FA-1-30 accumulated more than 4 g/liter of L-threonine in media containing 10% glucose, and the best producer, FAB-44, selected on a medium containing 5 mg/ml of AHV produced about 15 g/liter of L-threonine. Many of AHV resistant mutants selected on a medium containing 2 mg/ml of AHV accumulated L-lysine as well as L-threonine, AHV resistant mutants derived from FA-3-115 produced 10.7 g/liter of L-threonine maximally. AEC resistant mutants derived from strains BB–82 and BB–69, which were L-threonine producers derived from Br. flavum No. 2247 as AHV resistant mutants, did not produce L-threonine more than the parental strains, and moreover, many of them did not accumulate L-threonine but L-lysine. Homoserine dehydrogenases of crude extracts from L-threonine producing AHV resistant mutants derived from FA–1–30 and FA–3–115 were insensitive to the inhibition by L-threonine, and those of L-threonine and L-lysine producing AHV resistant mutants from FA–1–30 were partially sensitive.Correlation between L-threonine or L-lysine production and regulations of enzymatic activities of the mutants was discussed. 相似文献
57.
Tadashi Shimamura Satoe Iijima Mitsuhiro Hirayama Masato Iwashita Shigeru Akiyama Yuichi Takaku Sakae Yumoto 《Journal of trace elements in medicine and biology》2013,27(4):286-294
The concentrations of 22 major and trace elements in livers from rats aging from 5 to 113 weeks old were determined. The rats investigated were the same rats previously reported with respect to 29 elements in bones (femur) and 26 elements in kidneys. The samples were decomposed with high-purity nitric acid and hydrogen peroxide. Seven elements (Na, Mg, P, K, Ca, Fe and Zn) were determined by inductively coupled plasma atomic emission spectrometry (ICP-AES), and 15 elements (Mn, Co, Cu, As, Se, Rb, Sr, Mo, Cd, Sn, Sb, Cs, Ba, Pb and Bi) were determined by inductively coupled plasma mass spectrometry (ICP-MS). Analysis of variance (ANOVA) for age variations indicated that the concentrations of many elements, such as Mg, P, K, Mn, Fe, Cu, Zn, Sr, Mo and Cd, were almost constant across the ages of the rats with the exception of 5 weeks old (p > 0.05). Arsenic, Pb and Bi showed significant increasing trends, while Na and Co showed decreasing trends (p < 0.01). Selenium showed a decreasing trend except at the initial stage of 5–9 weeks old. Calcium, Rb, Sn, Sb, Cs and Ba showed significant age-related variations, but their patterns were not monotonic. The liver clearly contrasts with the kidneys, in which many elements showed significant age-related variations with increasing trends. The concentration ranges of Mg, P, K, Mn, Cu, Zn, and Mo were controlled within 15% across all ages of rats. The homeostasis of the aforementioned elements may be well established in the liver. The toxic elements, such as Cd, Pb and Bi, showed a narrow concentration range among age-matched rats. 相似文献
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59.
King-Wah Chiu Toshiaki Nakano Kuang-Den Chen Chia-Yun Lai Li-Wen Hsu Ho-Ching Chiu Ching-Yin Huang Yu-Fan Cheng Shigeru Goto Chao-Long Chen 《PloS one》2013,8(8)
This study used pyrosequencing to determine the proportional distribution of CYP3A5*3 genotypes to further confirm the homogeneous phenomenon that is observed when recipients and donors in living donor liver transplantation (LDLT) have a different single nucleotide polymorphism (SNP) genotype. We enrolled 42 recipient/living donor pairs and the SNPs of CYP3A5*3 were identified by polymerase chain reaction-restriction fragment length polymorphism. We performed 120 liver graft biopsies as part of clinical investigations after LDLT. Pyrosequencing of the CYP3A5*3 SNPs revealed that among the 16 recipients with the G/G genotype, 94.68% had the G and 5.32% the A allele. Among the 14 recipients with the A/G genotype, 78.08% had the G and 21.92% the A allele, and among the 12 recipients with the A/A genotype, 18.45% had the G and 81.55% the A allele. Among the 12 donors with the G/G genotype, 93.85% had the G and 6.14% the A allele. Among the 26 donors with the A/G genotype, 75.73% had the G and 24.27% the A allele, and among the 4 donors with the A/A genotype, 11.09% had the G and 88.91% the A allele. There were a total of 120 liver graft biopsy samples; among the 37 recipients with the G/G genotype, 89.74% had the G and 10.26% the A allele, among the 70 recipients with the A/G genotype, 71.57% had the G and 28.43% the A allele, and among the 13 recipients with the A/A genotype, 48.25% had the G and 51.75% the A allele. The proportional distribution of G and A alleles of the CYP3A5*3 SNP between recipients/donors and liver grafts after LDLT was significantly different (p<0.001). Pyrosequencing was useful in identifying detailed proportional changes of the CYP3A5*3 SNP allele distribution, and to confirm the homogeneous phenomenon when recipients and donors in LDLT have a different genotype. 相似文献
60.
Kiyoshi Migita Toru Arai Naoki Ishizuka Yuka Jiuchi Yasuharu Sasaki Yasumori Izumi Tetsuyuki Kiyokawa Eiichi Suematsu Tomoya Miyamura Hiroshi Tsutani Yojiro Kawabe Ryutaro Matsumura Shunsuke Mori Shiro Ohshima Shigeru Yoshizawa Kenji Kawakami Yasuo Suenaga Hideo Nishimura Toyohiko Sugimoto Hiroaki Iwase Hideyuki Sawada Haruhiro Yamashita Shigeyuki Kuratsu Fumitaka Ogushi Masaharu Kawabata Toshihiro Matsui Hiroshi Furukawa Seiji Bito Shigeto Tohma 《PloS one》2013,8(11)