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71.
Two novel cyano‐containing oligo(phenylenevinylene) (OPV) derivatives have been designed and synthesized. Photophysical and sensing properties of the two compounds were studied. Such studies reveal the intramolecular charge transfer process between cyano groups and OPV core. The results showed that the alkyl difference of substituted OPV leads to the changes of molecular configuration and metallo‐response of two compounds. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
72.
A major QTL for resistance to Gibberella stalk rot in maize 总被引:1,自引:0,他引:1
Qin Yang Guangming Yin Yanling Guo Dongfeng Zhang Shaojiang Chen Mingliang Xu 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2010,121(4):673-687
Fusarium graminearum Schwabe, the conidial form of Gibberella zeae, is the causal fungal pathogen responsible for Gibberella stalk rot of maize. Using a BC1F1 backcross mapping population derived from a cross between ‘1145’ (donor parent, completely resistant) and ‘Y331’ (recurrent
parent, highly susceptible), two quantitative trait loci (QTLs), qRfg1 and qRfg2, conferring resistance to Gibberella stalk rot have been detected. The major QTL qRfg1 was further confirmed in the double haploid, F2, BC2F1, and BC3F1 populations. Within a qRfg1 confidence interval, single/low-copy bacterial artificial chromosome sequences, anchored expressed sequence tags, and insertion/deletion
polymorphisms, were exploited to develop 59 markers to saturate the qRfg1 region. A step by step narrowing-down strategy was adopted to pursue fine mapping of the qRfg1 locus. Recombinants within the qRfg1 region, screened from each backcross generation, were backcrossed to ‘Y331’ to produce the next backcross progenies. These
progenies were individually genotyped and evaluated for resistance to Gibberella stalk rot. Significant (or no significant) difference in resistance reactions between homozygous and heterozygous genotypes
in backcross progeny suggested presence (or absence) of qRfg1 in ‘1145’ donor fragments. The phenotypes were compared to sizes of donor fragments among recombinants to delimit the qRfg1 region. Sequential fine mapping of BC4F1 to BC6F1 generations enabled us to progressively refine the qRfg1 locus to a ~500-kb interval flanked by the markers SSR334 and SSR58. Meanwhile, resistance of qRfg1 to Gibberella stalk rot was also investigated in BC3F1 to BC6F1 generations. Once introgressed into the ‘Y331’ genome, the qRfg1 locus could steadily enhance the frequency of resistant plants by 32–43%. Hence, the qRfg1 locus was capable of improving maize resistance to Gibberella stalk rot. 相似文献
73.
Wei Fan Stefan A. W. Bouwense Ross Crawford Yin Xiao 《Journal of molecular histology》2010,41(1):51-60
Despite the important physiological role of periosteum in the pathogenesis and treatment of osteoporosis, little is known
about the structural and cellular characteristics of periosteum in osteoporosis. To study the structural and cellular differences
in both diaphyseal and metaphyseal periosteum of osteoporotic rats, samples from the right femur of osteoporotic and normal
female Lewis rats were collected and tissue sections were stained with hematoxylin and eosin, antibodies or staining kit against
tartrate resistant acid phosphatase (TRAP), alkaline phosphatase (ALP), vascular endothelial growth factor (VEGF), von Willebrand
(vWF), tyrosine hydroxylase (TH) and calcitonin gene-related peptide (CGRP). The results showed that the osteoporotic rats
had much thicker and more cellular cambial layer of metaphyseal periosteum compared with other periosteal areas and normal
rats (P < 0.001). The number of TRAP+ osteoclasts in bone resorption pits, VEGF+ cells and the degree of vascularization were found to be greater in the cambial layer of metaphyseal periosteum of osteoporotic
rats (P < 0.05), while no significant difference was detected in the number of ALP+ cells between the two groups. Sympathetic nerve fibers identified by TH staining were predominantly located in the cambial
layer of metaphyseal periosteum of osteoporotic rats. No obvious difference in the expression of CGRP between the two groups
was found. In conclusion, periosteum may play an important role in the cortical bone resorption in osteoporotic rats and this
pathological process may be regulated by the sympathetic nervous system. 相似文献
74.
Haendeler J Yin G Hojo Y Saito Y Melaragno M Yan C Sharma VK Heller M Aebersold R Berk BC 《The Journal of biological chemistry》2003,278(50):49936-49944
Critical events for vasoconstrictor and growth factor signal transduction include stimulation of phospholipase Cgamma (PLCgamma) and elevation of intracellular calcium. c-Src has been proposed as a common mediator for these signals activated by both G protein-coupled receptors (GPCRs) and tyrosine kinase-coupled receptors (TKRs). Here we show that the GPCR kinase-interacting protein-1 (GIT1) is a substrate for c-Src that undergoes tyrosine phosphorylation in response to angiotensin II (AngII) and EGF in vascular smooth muscle and 293 cells. GIT1 associates with PLCgamma via the PLCgamma Src homology 2 and 3 domains constitutively, and the interaction is unaltered by AngII and EGF. GIT1 interaction with PLCgamma is required for PLCgamma activation based on inhibition of tyrosine phosphorylation and calcium mobilization after GIT1 knockdown with antisense GIT1 oligonucleotides. GIT1 interacts with PLCgamma via a novel Spa homology domain (SHD) and a coiled-coil domain. Deletion mutation analysis showed that GIT1(SHD) is required for AngII- and EGF-mediated PLCgamma activation (measured by phosphorylation of Tyr783 and inositol 1,4,5-trisphosphate formation). We propose that GIT1 is a novel regulator of PLCgamma function that mediates PLCgamma activation by c-Src and integrates signal transduction by GPCRs and TKRs. 相似文献
75.
Owing to the complex nature of V1VO ATPases, identification of neighboring subunits is essential for mechanistic understanding of this enzyme. Here, we describe the links between the V1 headpiece and the VO-domain of the yeast V1VO ATPase via subunit A and d as well as the VO subunits a and d using surface plasmon resonance and fluorescence correlation spectroscopy. Binding constants of about 60 and 200 nM have been determined for the a-d and d-A assembly, respectively. The data are discussed in light of subunit a and d forming a peripheral stalk, connecting the catalytic A3B3 hexamer with VO.
Structured summary
MINT-7012054: d (uniprotkb:P32366) binds (MI:0407) to A (uniprotkb:P17255) by fluorescence correlation spectroscopy (MI:0052)MINT-7012041: d (uniprotkb:P32366) binds (MI:0407) to A (uniprotkb:P17255) by surface plasmon resonance (MI:0107)MINT-7012028: d (uniprotkb:P32366) binds (MI:0407) to a (uniprotkb:P32563) by surface plasmon resonance (MI:0107) 相似文献76.
Cytoglobin, generated using genetic engineering method, is a kind of recombinant human stellate cell activation-associated
protein. We speculate that it could influence the development of hepatic fibrosis like Sellate cell activation-associated
protein which was discovered by Kawada et al. Therefore, we investigated its anti-fibrosis effect on liver both in vivo and
in vitro. During our research, we found that cytoglobin showed obvious effect compared with the control group on Thioacetamide-induced
liver fibrosis in SD rats, including significantly decrease in aspartate aminotransferase, Hyaluronic acid, laminin and collagen
I(Col I) levels in serum and hydroxyproline in livers, which are the important indices reflecting the degree of hepatic fibrosis.
Meanwhile, the viability of rat hepatic stellate cell line T6 (HSC-T6) cells was inhibited by cytoglobin and the apoptosis
induced by cytoglobin in HSC-T6 cells was detected by Annexin V/PI double staining. Activation of the caspase cascade including
caspase-3 for the intrinsic pathways was demonstrated. The results also showed that the expression of Bcl-2 protein decreased
whereas that of Bax protein increased, leading to an increase of the Bax/Bcl-2 ratio. Our results demonstrated that cytoglobin
exhibited anti-fibrosis activity on livers in vivo and in vitro, involving apoptosis induction. 相似文献
77.
78.
As an alternative to the mean regression model, the quantile regression model has been studied extensively with independent failure time data. However, due to natural or artificial clustering, it is common to encounter multivariate failure time data in biomedical research where the intracluster correlation needs to be accounted for appropriately. For right-censored correlated survival data, we investigate the quantile regression model and adapt an estimating equation approach for parameter estimation under the working independence assumption, as well as a weighted version for enhancing the efficiency. We show that the parameter estimates are consistent and asymptotically follow normal distributions. The variance estimation using asymptotic approximation involves nonparametric functional density estimation. We employ the bootstrap and perturbation resampling methods for the estimation of the variance-covariance matrix. We examine the proposed method for finite sample sizes through simulation studies, and illustrate it with data from a clinical trial on otitis media. 相似文献
79.
80.
Yin Li Zhiqiang Liu Fengjie Cui Yingying Xu Hui Zhao 《World journal of microbiology & biotechnology》2007,23(6):837-843
A new strain of Penicillium sp. ZH-30 that produces xylanase was isolated from soil. According to the morphology and comparison of internal transcribed
spacer (ITS) rDNA gene sequence, the strain Penicillium sp. ZH-30 was identified as a strain of Penicillium oxalicum. When xylan or wheat bran was used as substrate at 30°C for 3 days under submerged cultivation, xylanase production was 5.3
and 13.3 U ml−1, respectively. The temperature and pH for optimum activity were 50°C and 5.0–6.0, respectively. 相似文献