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31.
Tamio Ohno Jun-ichi Katoh Yoshiaki Kikkawa Hiromichi Yonekawa Masahiko Nishimura 《Experimental Animals》2003,52(5):415-417
To develop SMXA recombinant inbred (RI) strains as more valuable genetic resources, 302 microsatellite (Mit) loci were added to the strain distribution patterns (SDP) reported previously. The improved SDP were constructed in a total of 1085 loci containing 484 Mit markers, 571 restriction landmark genomic scanning (RLGS) spot markers and 30 others. This substantially improved SDP can be freely accessed on our homepage (http://www.med.nagoya-u.ac.jp/sisetu/SDP.htm). 相似文献
32.
Effect of triethylenepentaminehexaacetic acid on the renal damage in cadmium-treated Syrian hamsters 总被引:2,自引:0,他引:2
Toshiaki Shibasaki Q. -Y. Xu Iwao Ohno Fumio Ishimoto Osamu Sakai 《Biological trace element research》1995,50(2):157-165
Cadmium (Cd)-induced nephropathy was treated by triethylene-pentaminehexaacetic acid (TTHA) in male Syrian hamsters. Hamsters
injected three times a week with 3 mg/kg body wt CdCl2 showed proteinuria, urinaryN-acetyl-β-d-inglucosaminidase (NAG), and fractional excretion of sodium (FENa) when compared to saline-injected control. Cd-treated hamsters
injected ip with TTHA 10 mg/kg body wt five times a week showed reduction of renal damage, including reductions in urinary
protein (from 6.7±2.2 to 4.3±0.5 mg/d) and NAG (0.17±0.06 to 0.04±0.02 U/d). Urinary excretion of Cd was significantly increased
(from 87±51.3 to 3052±1485 mg/L) by TTHA administration. Cd concentration in renal cortical tissue was slightly reduced (26.4±3.0
to 21.8±2.7 mg/g. protein). Excretion of malondialdehyde (MDA) was increased only in Cd-injected hamsters (to 2.1±1.6 nM/L), and elevated MDA in renal cortical tissue was not reduced by the administration of TTHA (1041±105 vs 1104±358 nM/g protein). Glutathione (GSH) concentration in the renal cortex was significantly elevated after Cd administration and further
increased after TTHA administration (5.5±2.1 to 9.8±2.0 μg/50 mg protein). There were no marked effects on creatinine clearance
(Ccr) and hematocrit. Moreover, renal morphological changes were improved significantly by treatment with TTHA.
We demonstrated the efficacy of TTHA in the treatment of Cd-induced nephropathy in hamsters. Although the precise mechanism
of the TTHA effects on Cd-induced nephropathy has not been elucidated, it might involve GSH reducing the elevated MDA concentration
in renal tissue. 相似文献
33.
Accumulation of glutamate by osmotically stressed Escherichia coli is dependent on pH. 总被引:1,自引:0,他引:1 下载免费PDF全文
In the present study, we measured the accumulation of glutamate after hyperosmotic shock in Escherichia coli growing in synthetic medium. The accumulation was high in the medium containing sucrose at a pH above 8 and decreased with decreases in the medium pH. The same results were obtained when the hyperosmotic shock was carried out with sodium chloride. The internal level of potassium ions in cells growing at a high pH was higher than that in cells growing in a neutral medium. A mutant deficient in transport systems for potassium ions accumulated glutamate upon hyperosmotic stress at a high pH without a significant increase in the internal level of potassium ions. When the medium osmolarity was moderate at a pH below 8, E. coli accumulated gamma-aminobutyrate and the accumulation of glutamate was low. These data suggest that E. coli uses different osmolytes for hyperosmotic adaptation at different environmental pHs. 相似文献
34.
Production of a lipopeptide antibiotic, surfactin, by recombinant Bacillus subtilis in solid state fermentation 总被引:4,自引:0,他引:4
Production of a lipopeptide antibiotic, surfactin, in solid state fermentation (SSF) on soybean curd residue, Okara, as a solid substrate was carried out using Bacillus subtilis MI113 with a recombinant plasmid pC112, which contains lpa-14, a gene related to surfactin production cloned at our laboratory from a wild-type surfactin producer, B. subtilis RB14. The optimal moisture content and temperature for the production of surfactin were 82% and 37 degrees C, respectively. The amount of surfactin produced by MI113 (pC112) was as high as 2.0 g/kg wet weight, which was eight times as high as that of the original B. subtilis RB14 at the optimal temperature for surfactin production, 30 degrees C. Although the stability of the plasmid showed a similar pattern in both SSF and submerged fermentation (SMF), production of surfactin in SSF was 4-5 times more efficient than in SMF. (c) 1995 John Wiley & Sons, Inc. 相似文献
35.
In Japan, the green seaweed Monostroma is an important source of humanfood. Monostroma nitidum Wittrock (Japanese name: hitoegusa)
is cultivated in brackish waters and estuaries of central to southern Japan. The green seaweed Monostroma grows in the brackish
water area in the upper part of the intertidal zone in the warm waters. Artificial seed culture began with the collection
of many gametes in April. The resultant zygotes were allowed to adhere to plastic settlement boards (20 cm long and 10 cm
wide). The zygoteboards were then cultured in tanks (1 ×2 ×0.5 m) with fertiliser in a controlled growth room (10–87 μmol
photon m-2s-1). The cultivated zygotes on the board in the indoor tanks gradually increased in size from 10 to 40 μm in diameter during
May to early August. Zygote growth became slowed at the end of August. The zygotesmatured in early September, and the plates
were transferred into culture tanks in a dark room for dark treatment. Maturation of the zygote was promoted by providing
dark conditions for two weeks. The production of a concentrated zoospore solution from the mature blades was achieved by adding
fresh water at temperature 2–3 °C above that of the seeding vats. Zoospores were released in large numbers when exposed to
strong irradiance of 100 μmol photon m-2 s-1 for 30 min. The zygotes produced flat unicellular fronds at the germling stage. The technology of artificial seed culture
and zoospore release from the zygotes is based mainly on these experiments.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
36.
Preliminary investigation of feeding performance of larvae of early red-spotted grouper, Epinephelus coioides, reared with mixed zooplankton 总被引:5,自引:0,他引:5
Masanori Doi Joebert D. Toledo Ma Salvacion N. Golez Miguel de los Santos Atsushi Ohno 《Hydrobiologia》1997,358(1-3):259-263
Larvae of red-spotted grouper, Epinephelus coioides, were reared inoutdoor tanks with nauplii of copepods (mainly Pseudodiaptomus annandaleiand Acartia tsuensis) and/or rotifers, Brachionus rotundiformis. Grouperlarvae successfully started feeding on early stage nauplii even though theirabundance was as low as approximately 100 individuals l–1 andshowed better survival and growth thereafter compared to those fed withrotifers only. Incidence of feeding reached 100% on day 4 whennauplii were available and only on day 9 when rotifers were given alone.Larvae seemed to be poor feeders at the onset of feeding, attempting tocapture any food organisms in the tank water. Selective feeding ability oflarvae started from day 4 and the larvae then preferred to feed on medium-and large-size nauplii rather than on rotifers as they grew. Larvae appearedto have a better chance at surviving in the presence of early stage nauplii,which were probably caught more easily than rotifers. 相似文献
37.
Naruo Nikoh Naoyuki Iwabe Kei-ichi Kuma Mutsuhito Ohno Tsutomu Sugiyama Yoko Watanabe Kinya Yasui Zhang Shi-cui Katsuji Hori Yoshiro Shimura Takashi Miyata 《Journal of molecular evolution》1997,45(1):97-106
Previously we suggested that four proteins including aldolase and triose phosphate isomerase (TPI) evolved with approximately
constant rates over long periods covering the whole animal phyla. The constant rates of aldolase and TPI evolution were reexamined
based on three different models for estimating evolutionary distances. It was shown that the evolutionary rates remain essentially
unchanged in comparisons not only between different classes of vertebrates but also between vertebrates and arthropods and
even between animals and plants, irrespective of the models used. Thus these enzymes might be useful molecular clocks for
inferring divergence times of animal phyla. To know the divergence time of Parazoa and Eumetazoa and that of Cephalochordata
and Vertebrata, the aldolase cDNAs from Ephydatia fluviatilis, a freshwater sponge, and the TPI cDNAs from Ephydatia fluviatilis and Branchiostoma belcheri, an amphioxus, have been cloned and sequenced. Comparisons of the deduced amino acid sequences of aldolase and TPI from the
freshwater sponge with known sequences revealed that the Parazoa–Eumetazoa split occurred about 940 million years ago (Ma)
as determined by the average of two proteins and three models. Similarly, the aldolase and TPI clocks suggest that vertebrates
and amphioxus last shared a common ancestor around 700 Ma and they possibly diverged shortly after the divergence of deuterostomes
and protostomes. 相似文献
38.
Takeshi Haseba Isao Yamamoto Hajime Kamii Youkichi Ohno Tokinori Watanabe 《Biochemical genetics》1995,33(9-10):349-363
Although the AdhN/AdhN strain ofPeromyscus maniculatus (so-called ADH? deermouse) has been previously considered to be deficient in ADH, we found ADH isozymes of Classes II and III but not Class I in the liver of this strain. On the other hand, the AdhF/AdhF strain (so-called ADH+ deermouse), which has liver ADH activity, had Class I and III but not Class II ADH in the liver. In the stomach, Class III and IV ADHs were detected in both deermouse strains, as well as in the ddY mouse, which has the normal mammalian ADH system with four classes of ADH. These ADH isozymes were identified as electrophoretic phenotypes on the basis of their substrate specificity, pyrazole sensitivity, and immunoreactivity. Liver ADH activity of the ADH? strain was barely detectable in a conventional ADH assay using 15 mM ethanol as substrate; however, it increased markedly with high concentrations of ethanol (up to 3M) or hexenol (7 mM). Furthermore, in a hydrophobic reaction medium containing 1.0M t-butanol, liver ADH activity of this strain at low concentrations of ethanol (<100 mM) greatly increased (about sevenfold), to more than 50% that of ADH+ deermouse. These results were attributable to the presence of Class III ADH and the absence of Class I ADH in the liver of ADH? deermouse. It was also found that even the ADH+ strain has low liver ADH activity (<40% that of the ddY mouse) with 15 mM ethanol as substrate, probably due to low activity in Class I ADH. Consequently, liver ADH activity of this strain was lower than its stomach ADH activity, in contrast with the ddY mouse, whose ADH activity was much higher in the liver than in the stomach, as well as other mammals. Thus, the ADH systems in both ADH? and ADH+ deermouse were different not only from each other but also from that in the ddY mouse; the ADH? strain was deficient in only Class I ADH, and the ADH+ strain was deficient in Class II ADH and down-regulated in Class I ADH activity. Therefore, Class III ADH, which was found in both strains and activated allosterically, may participate in alcohol metabolism in deermouse, especially in the ADH? strain. 相似文献
39.
Michio Masuda John A. West Yukimasa Ohno Munenao Kurogi 《Journal of plant research》1984,97(1):107-125
Samples of theGigartina pacifica-ochotensis complex were collected at 21 localities around Hokkaido and northern Honshu. The carpospore and blade tip cultures showed 3 reproductive patterns. (1) 237 (86.8%) of the 273 cultured isolates derived from single plants have a direct type of life history. (2) 29 (10.6%) isolates exhibited a heteromorphic type with the alternation of foliose gametophytes and crustose tetrasporophytes. (3) 7 (2.6%) isolates showed a mixed pattern in which carposporelings developed intoPetrocelis-like crusts, basal discs with uprightGigartina blades, or chimera-like discs with compositePetrocelis-Gigartina anatomy. CulturedGigartina blades derived from bothG. pacifica andG. ochotensis were similar in morphology. In 18 cultures from 5 localitiesPetrocelis tetraspores developed into dioeciousGigartina gametophytes. A single tetrasporeling grew into aGigartina plant that reproduced directly. In hybridization experiments with 8 male and 14 female isolates from 4 localities on Hokkaido 85 (78.0%) of 109 were positive. On the basis of these and earlier studies it is concluded that a single species is present in northern Japan:G. pacifica Kjellm. has priority overG. ochotensis (Rupr.) Rupr. ex Yendo. 相似文献
40.
Ultrastructural localization of glycogen in the granulocytes of normal rabbit bone marrow. 总被引:1,自引:0,他引:1
The glycogen of rabbit granulocytes has been studied in glutaraldehyde and osmium tetroxide fixed bone marrow by the periodic acid-thiocarbohydrazide-silver proteinate procedure (PA-TCH-SP). The PA-TCH-SP procedure involved the staining of intracytoplasmic glycogen more densely than the routine lead citrate staining. The PA-TCH-SP procedure demonstrated the intracytoplasmic glycogen in all three kinds of granulocytes. Though a sequence of intensity was observed in each stage of cell maturation, intracytoplasmic glycogen increased generally in accordance with cell maturation in the granulocytes. Functional significance of the glycogen in the granulocytes was discussed in relation to its staining. A very weak reaction in the granules of the granulocytes was described in relation to their contents. 相似文献