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61.
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Yoko?MitaniEmail author Katsufumi?Sato Shinichiro?Ito Michael?F.?Cameron Donald?B.?Siniff Yasuhiko?Naito 《Polar Biology》2003,26(5):311-317
The under-ice behavior of two free-ranging female Weddell seals (Leptonychotes weddellii) was studied using geomagnetic, acceleration and velocity sensors at Big Razorback Island in McMurdo Sound, Antarctica. The seals' body angle and posture were calculated from the acceleration data and the heading from the geomagnetic intensity data. Together with swim speed, the seals' three-dimensional underwater dive path, heading and even posture were reconstructed for each dive. Each instrument was deployed for 2 days, during which time these females made multiple, deep ( m) dives, with average maximum depths of 236ᆯ m (n=4) and 244끁 m (n=40). Each seal appeared to choose a particular heading on which to descend. These headings were significantly different between seals and bouts (Watson's U2 test, P<0.05). These new instruments and methodologies are shown to provide valuable information on the fine-scale and complex movements of diving animals. 相似文献
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We assessed sexual variation in food quality and gut macrostructure in adult male and pregnant female sika deer, Cervus nippon (Temminck, 1838), in Japan during winter. These variations might have important implications relative to sexual differences in habitat use, forage acquisition, and digestive strategy. According to the sexual dimorphism-body size hypothesis the larger males would feed on poorer forage and have heavier stomach contents and heavier intestine contents and longer intestines than smaller females. However, the food quality in rumen contents of males was higher than, or at least similar with, that of pregnant females. In correspondence to food quality, the relative weights of stomach contents and intestines with contents, the relative lengths of intestines to the lengths of body and total intestines in pregnant females were similar to adult males. The relative weights of omasum and abomasum tissues in pregnant females were greater than in males. Our findings suggest sexual differences in feeding strategy in sika deer in Japan during winter. To meet greater nutritional demands of high metabolic rate and gestation, pregnant females seemed to maintain a greater volume of digesta in guts and had more stomach tissues than expected by the sexual dimorphism-body size hypothesis to compensate for poorer forage quality. 相似文献
65.
A role for the 30S subunit E site in maintenance of the translational reading frame 总被引:1,自引:0,他引:1 下载免费PDF全文
Aishwarya Devaraj Shinichiro Shoji Eric D. Holbrook Kurt Fredrick 《RNA (New York, N.Y.)》2009,15(2):255-265
The exit (E) site has been implicated in several ribosomal activities, including translocation, decoding, and maintenance of the translational reading frame. Here, we target the 30S subunit E site by introducing a deletion in rpsG that truncates the β-hairpin of ribosomal protein S7. This mutation (S7ΔR77–Y84) increases both −1 and +1 frameshifting but does not increase miscoding, providing evidence that the 30S E site plays a specific role in frame maintenance. Mutation S7ΔR77–Y84 also stimulates +1 programmed frameshifting during prfB′-lacZ translation in many synthetic contexts. However, no effect is seen when the E codon of the frameshift site corresponds to those found in nature, suggesting that E-tRNA release does not normally limit the rate of prfB frameshifting. Ribosomes containing S7ΔR77–Y84 exhibit an elevated rate of spontaneous reverse translocation and an increased K1/2 for E-tRNA. These effects are of similar magnitude, suggesting that both result from destabilization of E-tRNA. Finally, this mutation of the 30S E site does not inhibit EF-G-dependent translocation, consistent with a primary role for the 50S E site in the mechanism. 相似文献
66.
Abstract: We previously reported that an endogenous activating substance different from bovine serum albumin, phospholipids and heparin, exists in the extract from bovine pineal glands and that this substance interacts with tryptophan-5-monooxygenase under reducing conditions with sulfhydryl reagents, to stimulate monooxygenase activity. The present paper reports that the activating substance is of peptide nature; that it is sensitive to trypsin-digestion; and that it does not change the apparent K m 's for substrates, L-tryptophan and oxygen, and coenzyme, reduced biopterin or DMPH4 : but that it increases the V max 1.5- to 2.3-fold. These results suggest that an activating protein, present in some particles of the cell structure, activates tryptophan-5-monooxygenase under the regulation of a sulfhydryl compound. The apparent K m 's for reduced biopterin and DMPH4 were 77.2μM and 294 μM, respectively. The apparent K m 's for L-tryptophan and oxygen with reduced biopterin were 15.0 μM and 4.7%, respectively: with DMPH4 , they were 11.0 μM and 8.5%, respectively. Significant inhibition of both L-tryptophan and oxygen was observed with reduced biopterin, but not with DMPH4 (at the tested concentrations of up to 0.5 MM and 20%, respectively). 相似文献
67.
Hiroki Otani Hiromasa Yamamoto Munenori Takaoka Masakiyo Sakaguchi Junichi Soh Masaru Jida Tsuyoshi Ueno Takafumi Kubo Hiroaki Asano Kazunori Tsukuda Katsuyuki Kiura Shinji Hatakeyama Eiji Kawahara Yoshio Naomoto Shinichiro Miyoshi Shinichi Toyooka 《PloS one》2015,10(6)
TAE226, a bis-anilino pyrimidine compound, has been developed as an inhibitor of focal adhesion kinase (FAK) and insulin-like growth factor-I receptor (IGF-IR). In this study, we investigated the effect of TAE226 on non-small-cell lung cancer (NSCLC), especially focusing on the EGFR mutational status. TAE226 was more effective against cells with mutant EGFR, including the T790M mutant, than against cells with wild-type one. TAE226 preferentially inhibited phospho-EGFR and its downstream signaling mediators in the cells with mutant EGFR than in those with wild-type one. Phosphorylation of FAK and IGF-IR was not inhibited at the concentration at which the proliferation of EGFR-mutant cells was inhibited. Results of the in vitro binding assay indicated significant differences in the affinity for TAE226 between the wild-type and L858R (or delE746_A750) mutant, and the reduced affinity of ATP to the L858R (or delE746_A750) mutant resulted in good responsiveness of the L858R (or delE746_A750) mutant cells to TAE226. Of interest, the L858R/T790M or delE746_A750/T790M mutant enhanced the binding affinity for TAE226 compared with the L858R or delE746_A750 mutant, resulting in the effectiveness of TAE226 against T790M mutant cells despite the T790M mutation restoring the ATP affinity for the mutant EGFR close to that for the wild-type. TAE226 also showed higher affinity of about 15-fold for the L858R/T790M mutant than for the wild-type one by kinetic interaction analysis. The anti-tumor effect against EGFR-mutant tumors including T790M mutation was confirmed in mouse models without any significant toxicity. In summary, we showed that TAE226 inhibited the activation of mutant EGFR and exhibited anti-proliferative activity against NSCLCs carrying EGFR mutations, including T790M mutation. 相似文献
68.
Masayoshi Shinjoh Norio Sugaya Yoshio Yamaguchi Yuka Tomidokoro Shinichiro Sekiguchi Keiko Mitamura Motoko Fujino Hiroyuki Shiro Osamu Komiyama Nobuhiko Taguchi Yuji Nakata Naoko Yoshida Atsushi Narabayashi Michiko Myokai Masanori Sato Munehiro Furuichi Hiroaki Baba Hisayo Fujita Akihiro Sato Ichiro Ookawara Kenichiro Tsunematsu Makoto Yoshida Mio Kono Fumie Tanaka Chiharu Kawakami Takahisa Kimiya Takao Takahashi Satoshi Iwata Keio Pediatric Influenza Research Group 《PloS one》2015,10(8)
We assessed vaccine effectiveness (VE) against medically attended, laboratory-confirmed influenza in children 6 months to 15 years of age in 22 hospitals in Japan during the 2013–14 season. Our study was conducted according to a test-negative case-control design based on influenza rapid diagnostic test (IRDT) results. Outpatients who came to our clinics with a fever of 38°C or over and had undergone an IRDT were enrolled in this study. Patients with positive IRDT results were recorded as cases, and patients with negative results were recorded as controls. Between November 2013 and March 2014, a total of 4727 pediatric patients (6 months to 15 years of age) were enrolled: 876 were positive for influenza A, 66 for A(H1N1)pdm09 and in the other 810 the subtype was unknown; 1405 were positive for influenza B; and 2445 were negative for influenza. Overall VE was 46% (95% confidence interval [CI], 39–52). Adjusted VE against influenza A, influenza A(H1N1)pdm09, and influenza B was 63% (95% CI, 56–69), 77% (95% CI, 59–87), and 26% (95% CI, 14–36), respectively. Influenza vaccine was not effective against either influenza A or influenza B in infants 6 to 11 months of age. Two doses of influenza vaccine provided better protection against influenza A infection than a single dose did. VE against hospitalization influenza A infection was 76%. Influenza vaccine was effective against influenza A, especially against influenza A(H1N1)pdm09, but was much less effective against influenza B. 相似文献
69.
Eriko Kudo Manabu Taura Kouki Matsuda Masako Shimamoto Ryusho Kariya Hiroki Goto Shinichiro Hattori Shinya Kimura Seiji Okada 《Bioorganic & medicinal chemistry letters》2013,23(3):606-609
The anti-HIV-1 activity of GUT-70, a natural product derived from the stem bark of Chlophyllum brasiliense, was evaluated. GUT-70 inhibited HIV-1 replication in both acutely and chronically infected cells through suppression of NF-κB. Our results strengthen the idea that NF-κB pathway is one of the potential targets to control HIV-1 replication and that GUT-70 could serve as a lead compound to develop novel therapeutic agents against HIV-1 infection. 相似文献
70.
In germ cells, the function of which is to form the next generation, apoptotic cell death occurs during development, as in the case of somatic cells. In this study, we show that Bcl-x knockout heterozygous (Bcl-x(+/-)) mice exhibit severe defects in male germ cells during development. A substantial increase in apoptosis of male germ cells occurs at around embryonic day 13.5 (E13.5) in Bcl-x(+/-) embryos, leading to hypoplasia of postnatal testes and reduced fertility. On the other hand, female germ cells at the same stages do not show discernible differences between wild-type and Bcl-x(+/-) embryos. This phenotype of Bcl-x haploinsufficiency shows that regulation of apoptosis becomes different between the sexes at around the onset of sex differentiation. Through this study, we found that, in wild-type embryos, (1) apoptosis is much more frequent (approximately 10 times) in the male than in female germ cells, and (2) expression of Bcl-xL, but not that of Bax, is higher in female than in male germ cells, at around E13.5. Male fetal germ cells, cultured with gonadal somatic cells in vitro, showed higher frequencies of apoptosis than those cultured without gonadal somatic cells. On the other hand, in the absence of gonadal somatic cells, both male and female fetal germ cells in vitro showed similar frequencies of apoptosis to female fetal germ cells in vivo. Therefore, male germ cell apoptosis, of which the default pathway is similar to that of the female, is likely to be influenced by male gonadal environments. 相似文献