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排序方式: 共有1212条查询结果,搜索用时 15 毫秒
51.
Yusuke K. Kawai Kensuke P. Watanabe Akihiro Ishii Aiko Ohnuma Hirofumi Sawa Yoshinori Ikenaka Mayumi Ishizuka 《Comparative biochemistry and physiology. Part D, Genomics & proteomics》2013,8(3):201-208
The cytochrome P450 (CYP) 1–3 families are involved in xenobiotic metabolism, and are expressed primarily in the liver. Ostriches (Struthio camelus) are members of Palaeognathae with the earliest divergence from other bird lineages. An understanding of genes coding for ostrich xenobiotic metabolizing enzyme contributes to knowledge regarding the xenobiotic metabolisms of other Palaeognathae birds. We investigated CYP1–3 genes expressed in female ostrich liver using a next-generation sequencer. We detected 10 CYP genes: CYP1A5, CYP2C23, CYP2C45, CYP2D49, CYP2G19, CYP2W2, CYP2AC1, CYP2AC2, CYP2AF1, and CYP3A37. We compared the gene expression levels of CYP1A5, CYP2C23, CYP2C45, CYP2D49, CYP2G19, CYP2AF1, and CYP3A37 in ostrich liver and determined that CYP2G19 exhibited the highest expression level. The mRNA expression level of CYP2G19 was approximately 2–10 times higher than those of other CYP genes. The other CYP genes displayed similar expression levels. Our results suggest that CYP2G19, which has not been a focus of previous bird studies, has an important role in ostrich xenobiotic metabolism. 相似文献
52.
Objective:
To assess time trends in measurement error of BMI and the sensitivity/specificity of classifying weight status in the United States by analyzing the difference in BMI between self‐reported and measured height and weight.Design and Methods:
Data from 18,394 respondents aged 20‐89 years from the National Health and Nutrition Examination Survey (NHANES) from 1999 through 2008 were analyzed. Multiple linear regression and logistic regression models estimated trends in reporting bias and misclassification of weight status by BMI categories, sex, age, and racial/ethnic groups, adjusting for the sampling design.Results:
We find no evidence that there are time trends in the accuracy of self‐report by BMI categories, sex, age, or racial/ethnic groups. The well‐known downward bias in self‐report has remained stable over the last decade; approximately one in six to seven obese individuals were misclassified as nonobese due to underestimation of BMI.Conclusion:
Increases in obesity rates based on self‐reported height and weight are likely to reflect actual weight increases and are not inflated by changes in reporting accuracy. 相似文献53.
Hirotsugu Ohkubo Yoshihiro Kanemitsu Takehiro Uemura Osamu Takakuwa Masaya Takemura Ken Maeno Yutaka Ito Tetsuya Oguri Nobutaka Kazawa Ryuji Mikami Akio Niimi 《PloS one》2016,11(3)
BackgroundAlthough several computer-aided computed tomography (CT) analysis methods have been reported to objectively assess the disease severity and progression of idiopathic pulmonary fibrosis (IPF), it is unclear which method is most practical. A universal severity classification system has not yet been adopted for IPF.ObjectiveThe purpose of this study was to test the correlation between quantitative-CT indices and lung physiology variables and to determine the ability of such indices to predict disease severity in IPF.MethodsA total of 27 IPF patients showing radiological UIP pattern on high-resolution (HR) CT were retrospectively enrolled. Staging of IPF was performed according to two classification systems: the Japanese and GAP (gender, age, and physiology) staging systems. CT images were assessed using a commercially available CT imaging analysis workstation, and the whole-lung mean CT value (MCT), the normally attenuated lung volume as defined from −950 HU to −701 Hounsfield unit (NL), the volume of the whole lung (WL), and the percentage of NL to WL (NL%), were calculated.ResultsCT indices (MCT, WL, and NL) closely correlated with lung physiology variables. Among them, NL strongly correlated with forced vital capacity (FVC) (r = 0.92, P <0.0001). NL% showed a large area under the receiver operating characteristic curve for detecting patients in the moderate or advanced stages of IPF. Multivariable logistic regression analyses showed that NL% is significantly more useful than the percentages of predicted FVC and predicted diffusing capacity of the lungs for carbon monoxide (Japanese stage II/III/IV [odds ratio, 0.73; 95% confidence intervals (CI), 0.48 to 0.92; P < 0.01]; III/IV [odds ratio. 0.80; 95% CI 0.59 to 0.96; P < 0.01]; GAP stage II/III [odds ratio, 0.79; 95% CI, 0.56 to 0.97; P < 0.05]).ConclusionThe measurement of NL% by threshold-based volumetric CT analysis may help improve IPF staging. 相似文献
54.
Masamichi Yamashita Yoshihiko Hirohashi Toshihiko Torigoe Hiroki Kusumoto Aiko Murai Tomohiro Imagawa Noriyuki Sato 《PloS one》2016,11(1)
Cancer stem-like cells (CSCs)/cancer-initiating cells (CICs) are defined by their abilities of tumor initiation, self-renewal and differentiation. In a previous study, we showed by gene knockdown using siRNA and gene overexpression experiments that Dnaj (Hsp40) homolog, subfamily B, member 8 (DNAJB8), a role in the maintenance, of renal cell carcinoma CSCs/CICs. In the present study, we established Dnajb8 knockout (KO) renal cell carcinoma (RCC) line cells (RenCa cells) and analyzed the cells to confirm the function of Dnajb8 in RCC CSCs/CICs. Dnajb8 KO cells showed reduced ratios of side population cells and reduced sphere forming ability. An in vivo single cell tumor initiation assay revealed that the numbers of CSCs/CICs were 3 in 4 wild-type RenCa cells and 1 in 4 Dnajb8 KO cells. Dnajb8 KO cells showed sensitivity to Docetaxel. On the other hand, Dnajb8 KO cells did not show any sensitivities to stresses including low pH, low glucose, heat shock and sensitivity to cisplatin. The results indicate that Dnajb8 has a role in tumor initiation, side population ratio and sphere formation but it is dispensable for stress responses. 相似文献
55.
Yoshinori Yabuki Takashi Nagai Keiya Inao Junko Ono Nobuyuki Aiko Nobutoshi Ohtsuka 《Bioscience, biotechnology, and biochemistry》2016,80(10):2069-2075
Laboratory experiments were performed to determine the sampling rates of pesticides for the polar organic chemical integrative samplers (POCIS) used in Japan. The concentrations of pesticides in aquatic environments were estimated from the accumulated amounts of pesticide on POCIS, and the effect of water temperature on the pesticide sampling rates was evaluated. The sampling rates of 48 pesticides at 18, 24, and 30 °C were obtained, and this study confirmed that increasing trend of sampling rates was resulted with increasing water temperature for many pesticides. 相似文献
56.
Plant Ecology - Japanese stinging nettles, Urtica thunbergiana, in Nara Park (660 ha), central Japan, where several hundred sika deer Cervus nippon have been protected for... 相似文献
57.
Kojima H Nemoto A Uemura T Honma R Ogura M Liu Y 《The Journal of biological chemistry》2001,276(22):19238-19243
This is the first report of a novel serine/threonine kinase, rabbit death-associated protein (DAP) kinase-related apoptosis-inducing protein kinase 1 (rDRAK1), involved in osteoclast apoptosis. We searched for osteoclast-specific genes from a cDNA library of highly enriched rabbit osteoclasts cultured on ivory. One of the cloned genes has a high homology with human DRAK1 (hDRAK1), which belongs to the DAP kinase subfamily of serine/threonine kinases. By screening a rabbit osteoclast cDNA library and 5'-RACE (rapid amplification of cDNA ends), we obtained a full length of this cDNA, termed rDRAK1. The sequencing data indicated that rDRAK1 has 88.0, 44.6, 38.7, and 42.3% identity with hDRAK1, DAP kinase, DRP-1, and ZIP (zipper-interacting protein) kinase, respectively. To clarify the role of DRAK1 in osteoclasts, we examined the effect of three osteoclast survival factors (interleukin-1, macrophage colony-stimulating factor, and osteoclast differentiation-inducing factor) on rDRAK1 mRNA expression and the effect of rDRAK1 overexpression on osteoclast apoptosis. The results suggested that these three survival factors were proved to inhibit rDRAK1 expression in rabbit osteoclasts. After transfection of a rDRAK1 expression vector into cultured osteoclasts, overexpressed rDRAK1 was localized exclusively to the nuclei and induced apoptosis. Hence, rDRAK1 may play an important role in the core apoptosis program in osteoclast. 相似文献
58.
The adapter protein Crkl links Cbl to C3G after integrin ligation and enhances cell migration 总被引:8,自引:0,他引:8
Crkl, an SH2-SH3-SH3 adapter protein, is one of the major tyrosine phosphoproteins detected in cells from patients with chronic myelogenous leukemia. Crkl binds to BCR/ABL through its N-terminal SH3 domain and is known to interact with several signaling proteins that have been implicated in integrin signaling, including Cbl, Cas, Hef-1, and paxillin. We have previously shown that overexpression of Crkl enhances adhesion to extracellular matrix proteins through beta(1) integrins. In this study, the effects of Crkl on spontaneous and chemokine-directed migration of the hematopoietic cell line Ba/F3 were examined. Full-length, SH2-, and SH3(N)-domain deletion mutants of Crkl were expressed transiently as fusion proteins with green fluorescent protein. Successfully transfected cells were isolated by fluorescence-activated cell sorting. The ability of these cells to migrate across a fibronectin-coated membrane, either spontaneously or in response to the chemokine stromal-derived factor-1alpha, was determined. Cells expressing green fluorescent protein alone were not distinguishable from untransfected or mock transfected Ba/F3 cells. However, Ba/F3 cells overexpressing full-length Crkl were found to have an increase in spontaneous migration of 2.8 +/- 0.6-fold in seven independent assays. The enhancement of migration required both the SH2 domain and the N-terminal SH3 domain. Migration in response to stromal-derived factor-1alpha was not significantly enhanced by overexpression of Crkl. Overexpression of Crkii also augmented spontaneous migration but to a lesser degree than did Crkl. Because the SH2 domain was required for enhanced migration, we looked for changes in phosphotyrosine containing proteins coprecipitating with Crkl, but not Crkl DeltaSH2, after integrin cross-linking. Full-length Crkl, but not CrklDeltaSH2, coprecipitated with a single major tyrosine phosphoprotein with an M(r) of approximately 120 kDa, identified as Cbl. The major Crkl SH3-binding protein in these cells was found to be the guanine nucleotide exchange factor, C3G. Interestingly, overexpression of C3G also enhanced migration, suggesting that a Cbl-Crkl-C3G complex may be involved in migration signaling in Ba/F3 cells. These data suggest that Crkl is involved in signaling pathways that regulate migration, possibly through a complex with Cbl and C3G. 相似文献
59.
Cell-wall synthesis in Chlorella vulgaris, an autospore-forming alga, was observed using the cell wall-specific fluorescent dye Fluostain I. The observation suggested two clearly distinguishable stages in cell-wall synthesis: moderate synthesis during the cell-growth process and rapid synthesis at the cell-division stage. We used electron microscopy to examine the structural changes that occurred with growth in the premature daughter cell wall during the cell-growth and cell-division phases. The cell began to synthesize a new daughter cell wall shortly after its release from the autosporangium. A very thin daughter cell wall, with a thickness of about 2 nm, was formed inside the mother cell wall and completely enveloped the outer surface of the plasma membrane of the cell. The daughter cell wall gradually increased in thickness from 2 to 3.8 nm. During the protoplast-division phase in the cell-division stage, the daughter cell wall expanded on the surface of the invaginating plasma membrane of the cleavage furrow, accompanied by active synthesis of the cell wall, which increased in thickness from 3.8 to 6.1 nm. The daughter cell matured into an autospore while completely enclosed by its own thickening (from 6.1 to 17 nm) wall. Finally, the released daughter cell was enclosed by its own cell wall after the mother cell wall burst. The daughter cell with mature wall thickness (17–21 nm) emerged as a small, but complete, autospore. 相似文献
60.
Water relations, proline content and gas exchange of leaf were investigated under periodic water stress for two C3 plants
(eggplant and tomato) in a greenhouse to study comparative adaptive responses. Although both species showed reduced water
content of leaf and increased osmolality and proline content under low soil water potential, the recovery capacity after the
stress was better in eggplant than tomato. Both species over-accumulated proline under low soil water potential and returned
to its initial concentration during the recovery, indicating that proline may act as an osmoprotectant during drought. Proline
was directly corresponding with osmolality during stress, and dehydration stress reduced the gas exchange parameters such
as transpiration rate (ET), stomatal conductance (GS), and photosynthesis rate (Pn). At the final stage of the experiment
both species showed 2.6 and 3.3 times lower Pn and 27 and 19 times lower GS for eggplant and tomato, respectively, as compared
to control. But after stress was relieved by rewatering, both plants increased GS for 2 to 3 times and Pn for 4.5 times. Eggplant
showed better water use efficiency (WUE) in relation to fruit production under the stress than tomato. Higher biomass allocation
at root and fruit parts in eggplant indicated more efficient recovery than that of tomato. These findings inferred that both
C3 plants developed internal complementary drought survival mechanism by lowering relative water content, increasing proline,
and decreasing stomatal conductance but eggplants withstood the periodic draughting better than tomato, mainly due to its
ability to recover from a water stress condition. 相似文献