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991.
Takeshi Odajima Minoko Takanashi Hiroki Sugimori Taiko Tanba Kentaro Yoshinaga Toshiko Motoji Masaya Munakata Kazunori Nakajima Mutsuhiko Minami 《PloS one》2016,11(2)
We conducted a cross-sectional study to elucidate factors contributing to vasovagal reaction (VVR), the most frequent side effect following whole blood and apheresis donations. Complications recorded at the collection sites after voluntary donations by the Japanese Red Cross Tokyo Blood Center (JRC), in the 2006 and 2007 fiscal years, were analyzed by both univariate analysis and the multivariate conditional logistic regression model. Of 1,119,716 blood donations over the full two years, complications were recorded for 13,320 donations (1.18%), among which 67% were VVR. There were 4,303 VVR cases which had sufficient information and could be used for this study. For each VVR case, two sex- and age-matched controls (n = 8,606) were randomly selected from the donors without complications. Age, sex, body mass index (BMI), predonation blood pressure, pulse and blood test results, including total protein, albumin, and hemoglobin, were compared between the VVR group and the control group. In univariate analysis, the VVR group was significantly younger, with a lower BMI, higher blood pressure and higher blood protein and hemoglobin levels than the control group (p<0.001). Furthermore, blood protein and hemoglobin levels showed dose-dependent relationships with VVR incidences by the Cochran-Armitage trend test (p<0.01). For both sexes, after adjusting for confounders with the multivariate conditional logistic regression model, the higher than median groups for total protein (male: OR 1.97; 95%CI 1.76,-2.21; female: OR 2.29; 95%CI 2.05–2.56), albumin (male: 1.75; 1.55–1.96; female: 1.76; 1.57–1.97) and hemoglobin (male: 1.98; 1.76–2.22; female: 1.62; 1.45–1.81) had statistically significant higher risk of VVR compared to the lower than median groups. These elevated serum protein and hemoglobin levels might offer new indicators to help understand VVR occurrence. 相似文献
992.
993.
Identification of honeybee antennal proteins/genes expressed in a sex- and/or caste selective manner
We identified three candidate proteins/genes involved in caste and/or sex-specific olfactory processing in the honeybee Apis mellifera L., that are differentially expressed between the antennae of the worker, queen, and drone honeybees using SDS-polyacrylamide gel electrophoresis or the differential display method. A protein was identified, termed D-AP1, that was expressed preferentially in drone antennae when compared to those of workers. cDNA cloning revealed that D-AP1 is homologous to carboxylesterases. Enzymatic carboxylesterase activity in the drone antennae was higher than in the workers, suggesting its dominant function in the drone antennae. In contrast, two proteins encoded by genes termed W-AP1 and Amwat were expressed preferentially in worker antennae when compared to those of queens. W-AP1 is homologous to insect chemosensory protein, and Amwat encodes a novel secretory protein. W-AP1 is expressed selectively in worker antennae, while Amwat is expressed both in the antennae and legs of the workers. These findings suggest that these proteins are involved in the antennal function characteristic to drone or worker honeybees. 相似文献
994.
Sperm cryopreservation is useful for the effective storage of genomic resources derived from genetically engineered mice. However, freezing the sperm of C57BL/6 mice, the most commonly used genetic background for genetically engineered mice, considerably reduces its fertility. We previously reported that methyl-beta-cyclodextrin dramatically improved the fertility of frozen/thawed C57BL/6 mouse sperm. Recently, it was reported that exposing sperm to reduced glutathione may alleviate oxidative stress in frozen/thawed mouse sperm, thereby enhancing in vitro fertilization (IVF); however, the mechanism underlying this effect is poorly understood. In the present study, we examined the combined effects of methyl-beta-cyclodextrin and reduced glutathione on the fertilization rate of IVF with frozen/thawed C57BL/6 mouse sperm and the characteristic changes in the zona pellucida induced by reduced glutathione. Adding reduced glutathione to the fertilization medium increased the fertilization rate. Methyl-beta-cyclodextrin and reduced glutathione independently increased fertilization rates, and their combination produced the strongest effect. We found that reduced glutathione increased the amount of free thiols in the zona pellucida and promoted zona pellucida enlargement. Finally, 2-cell embryos produced by IVF with the addition of reduced glutathione developed normally and produced live offspring. In summary, we have established a novel IVF method using methyl-beta-cyclodextrin during sperm preincubation and reduced glutathione during the IVF procedure to enhance fertility of frozen/thawed C57BL/6 mouse sperm. 相似文献
995.
In the polyol fermentation by Candida zeylanoides KY6166, which occurred preferentially by keeping the pH of medium at acidic side (below 4.0), phosphate ion played a precise role in the conversion of erythritol fermentation to d-mannitol fermentation. Enzymatic studies on the conversion mechanism provided the following evidences.The enzymes involved in pentosephosphate cycle were considerably depressed in polyol production phase in which intracellular pH ranged from 5.5 to 5.7. Particularly transaldolase responsible for the synthesis of erythrose 4-phosphate and fructose 6-phosphate from glyceraldehyde 3-phosphate plus d-sedoheptulose 7-phosphate was significantly depressed at pH 5.5. Besides, transketolase which participated directly in the formation of erythrose 4-phosphate from fructose 6-phosphate was significantly inhibited by phosphate ion. Glucose 6-phosphate dehydrogenase was slightly inhibited by phosphate ion.The enzymes involved in pentosephosphate cycle were considerably depressed in polyol production phase in which intracellular pH ranged from 5.5 to 5.7. Particularly transaldolase responsible for the synthesis of erythrose 4-phosphate and fructose 6-phosphate from glyceraldehyde 3-phosphate plus d-sedoheptulose 7-phosphate was significantly depressed at pH 5.5. Besides, transketolase which participated directly in the formation of erythrose 4-phosphate from fructose 6-phosphate was significantly inhibited by phosphate ion. Glucose 6-phosphate dehydrogenase was slightly inhibited by phosphateion. From these results, the alteration from erythritol fermentation to mannitol fermentation by phosphate ion was explained as the result of the change in the level of erythrose 4-phosphate and fructose 6-phosphate which was caused by the inhibition of transketolase. 相似文献
996.
Extraction and preliminary characterization of maturation-promoting factor from starfish oocytes 总被引:6,自引:0,他引:6
Cytoplasm of maturing starfish oocytes possesses a factor which induces maturation upon injection into immature oocytes. Such maturation-promoting factor (MPF) was extracted from maturing oocytes of Asterina pectinifera and characterized preliminarily. After 1-methyladenine (1-MeAde) treatment, maturing oocytes were packed in a centrifuge tube to remove jelly and excess medium, and then crushed by centrifugation. The turbid supernatant was homogenized with a buffer containing NaF, Na-beta-glycerophosphate, ATP, EGTA and leupeptin, followed by centrifugation. MPF extracted in the supernatant was purified partially by ammonium sulfate precipitation, hydrophobic chromatography on pentyl-agarose and gel filtration on Sephacryl S-300. The final material induced maturation in the recipient starfish oocytes when 0.5 ng of protein was injected in a volume of 400 pl. The maturation response included germinal vesicle breakdown, and formation of polar bodies and egg pronucleus. Such MPF preparation induced maturation in oocytes of Xenopus laevis as well. Further, starfish MPF was found to be a heat-labile protein; its molecular weight (MW) was estimated as 300 X 10(3) D by gel filtration and its sedimentation coefficient value as 5S by centrifugation on sucrose density gradients. 相似文献
997.
Abstract The polyene antibiotic, amphotericin B, at high concentrations (5–20 μg/ml) induced particle-free smooth areas in the plasma membranes of Saccharomyces cerevisiae and Candida albicans . These areas occured more or less over the entire plasma membrane of unbudded cells. In budded cells, however, the neck between the mother and bud did not undergo deformation. This suggests the strong interaction between the filamentous ring, which is firmly attached to the neck plasma membrane, and plasma membrane particles in the neck regions. 相似文献
998.
Yuko Kanemaru Fumihito Hasebe Takeo Tomita Tomohisa Kuzuyama Makoto Nishiyama 《Journal of bacteriology》2013,195(17):3845-3853
Thermus thermophilus exhibits hypersensitivity to a lysine analog, (S)-2-aminoethyl-cysteine (AEC). Cosmid libraries were constructed using genomes from two AEC-resistant mutants, AT10 and AT14, and the cosmids that conferred AEC resistance on the wild-type strain were isolated. When the cosmid library for mutant AT14 was screened, two independent cosmids, conferring partial AEC resistance to the wild type, were obtained. Two cosmids carried a common genomic region from TTC0795 to TTC0810. This region contains genes encoding an ATP-binding cassette (ABC) transporter consisting of TTC0806/TTC0795, using TTC0807 as the periplasmic substrate-binding protein. Sequencing revealed that AT14 carries mutations in TTC0795 and TTC0969, causing decreases in the thermostability of the products. TTC0969 encodes the nucleotide-binding protein of a different ABC transporter consisting of TTC0967/TTC0968/TTC0969/TTC0970 using TTC0966 as the periplasmic substrate-binding protein. By similar screening for cosmids constructed for the mutant AT10, mutations were found at TTC0807 and TTC0969. Mutation in either of the transporter components gave partial resistance to AEC in the wild-type strain, while mutations of both transporters conferred complete AEC resistance. This result indicates that both transporters are involved in AEC uptake in T. thermophilus. To elucidate the mechanism of AEC uptake, crystal structures of TTC0807 were determined in several substrate-binding forms. The structures revealed that TTC0807 recognizes various basic amino acids by changing the side-chain conformation of Glu19, which interacts with the side-chain amino groups of the substrates. 相似文献
999.
Hisaka Kurita Seiichiroh Ohsako Shin-ichi Hashimoto Jun Yoshinaga Chiharu Tohyama 《The Journal of nutritional biochemistry》2013,24(1):256-266
Zinc (Zn) deficiency in utero has been shown to cause a variety of disease states in children in developing countries, which prompted us to formulate the hypothesis that fetal epigenetic alterations are induced by zinc deficiency in utero. Focusing on metallothionein (MT), a protein that contributes to Zn transport and homeostasis, we studied whether and how the prenatal Zn status affects gene expression. Pregnant mice were fed low-Zn (IU-LZ, 5.0 μg Zn/g) or control (IU-CZ, 35 μg Zn/g) diet ad libitum from gestation day 8 until delivery, with a regular diet thereafter. Bisulfite genomic sequencing for DNA methylation and chromatin immunoprecipitation assay for histone modifications were performed on the MT2 promoter region. We found that 5-week-old IU-LZ mice administered cadmium (Cd) (5.0 mg/kg b.w.) have an elevated abundance of MT2 mRNA compared with IU-CZ mice. Alteration of histone modifications in the MT2 promoter region having metal responsive elements (MREs) was observed in 1-day-old and 5-week-old IU-LZ mice compared with IU-CZ mice. In addition, prolongation of MTF1 binding to the MT2 promoter region in 5-week-old IU-LZ mice upon Cd exposure is considered to contribute to the enhanced MT2 induction. In conclusion, we found for the first time that Zn deficiency in utero induces fetal epigenetic alterations and that these changes are being stored as an epigenetic memory until adulthood. 相似文献
1000.
Shoko Toyama Naoto Tamura Kazuhiko Haruta Takeo Karakida Shigeyuki Mori Tetsuo Watanabe Takao Yamori Yoshinari Takasaki 《Arthritis research & therapy》2010,12(3):R92