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931.
Julie Hoover-Fong Nara Sobreira Julie Jurgens Peggy Modaff Carrie Blout Ann Moser Ok-Hwa Kim Tae-Joon Cho Sung?Yoon Cho Sang?Jin Kim Dong-Kyu Jin Hiroshi Kitoh Woong-Yang Park Hua Ling Kurt?N. Hetrick Kimberly?F. Doheny David Valle Richard?M. Pauli 《American journal of human genetics》2014,94(1):105-112
932.
Karina Tuz Ruxandra Bachmann-Gagescu Diana?R. O’Day Kiet Hua Christine?R. Isabella Ian?G. Phelps Allan?E. Stolarski Brian?J. O’Roak Jennifer?C. Dempsey Charles Lourenco Abdulrahman Alswaid Carsten?G. B?nnemann Livija Medne Sheela Nampoothiri Zornitza Stark Richard?J. Leventer Meral Top?u Ali Cansu Sujatha Jagadeesh Stephen Done Gisele?E. Ishak Ian?A. Glass Jay Shendure Stephan?C.F. Neuhauss Chad?R. Haldeman-Englert Dan Doherty Russell?J. Ferland 《American journal of human genetics》2014,94(1):62-72
Joubert syndrome (JBTS) is a recessive ciliopathy in which a subset of affected individuals also have the skeletal dysplasia Jeune asphyxiating thoracic dystrophy (JATD). Here, we have identified biallelic truncating CSPP1 (centrosome and spindle pole associated protein 1) mutations in 19 JBTS-affected individuals, four of whom also have features of JATD. CSPP1 mutations explain ∼5% of JBTS in our cohort, and despite truncating mutations in all affected individuals, the range of phenotypic severity is broad. Morpholino knockdown of cspp1 in zebrafish caused phenotypes reported in other zebrafish models of JBTS (curved body shape, pronephric cysts, and cerebellar abnormalities) and reduced ciliary localization of Arl13b, further supporting loss of CSPP1 function as a cause of JBTS. Fibroblasts from affected individuals with CSPP1 mutations showed reduced numbers of primary cilia and/or short primary cilia, as well as reduced axonemal localization of ciliary proteins ARL13B and adenylyl cyclase III. In summary, CSPP1 mutations are a major cause of the Joubert-Jeune phenotype in humans; however, the mechanism by which these mutations lead to both JBTS and JATD remains unknown. 相似文献
933.
Li Jiang Dongxu He Dantong Yang Zhen Chen Qiongxi Pan Aiqin Mao Yanfei Cai Xiyuan Li Hui Xing Mei Shi Yun Chen Iain C. Bruce Teng Wang Linfang Jin Xiaowei Qi Dong Hua Jian Jin Xin Ma 《FEBS letters》2014
To investigate the role of microRNAs in the development of chemoresistance and related epithelial–mesenchymal transition (EMT), we examined the effect of miR-489 in adriamycin (ADM)-resistant human breast cancer cells (MCF-7/ADM). MiR-489 was significantly suppressed in MCF-7/ADM cells compared with chemosensitive parental control MCF-7/WT cells. Forced-expression of miR-489 reversed chemoresistance. Furthermore, Smad3 was identified as the target of miR-489 and is highly expressed in MCF-7/ADM cells. Forced expression of miR-489 both inhibited Smad3 expression and Smad3 related EMT properties. Finally, the interactions between Smad3, miR-489 and EMT were confirmed in chemoresistant tumor xenografts and clinical samples, indicating their potential implication for treatment of chemoresistance. 相似文献
934.
One approach to treating the dengue virus infection is to inhibit its NS2B-NS3 protease that plays a vital role in virus maturation. However, the lack of structural information on the active conformation of the protease hindered related drug design. With a co-expression system, we obtained the active two-component protease in its unlinked form. BPTI shows strong competitive inhibitory activity (Ki = 6.5 nM) against this unlinked protease, which adopts a closed conformation. Based on the biochemical and NMR perturbation information, an inhibition model of BPTI to NS2B-NS3 protease is proposed. 相似文献
935.
Pulsed electromagnetic fields (PEMF) have been used widely to treat nonunion fractures and related problems in bone healing, as a biological and physical method. With the use of Helmholtz coils and PEMF stimulators to generate uniform time‐varying electromagnetic fields, the effects of extremely low frequency electromagnetic fields on bone mineral density (BMD) and local factor production in disuse osteoporosis (DOP) rats were investigated. Eighty 4‐month‐old female Sprague Dawley (SD) rats were randomly divided into intact (INT) group, DOP group, calcitonin‐treated (CT) group, and PEMF stimulation group. The right hindlimbs of all the rats were immobilized by tibia‐tail fixation except for those rats in the INT group. Rats in the CT group were injected with calcitonin (2 IU/kg, i.p., once a day) and rats in the PEMF group were irradiated with PEMF immediately postoperative. The BMD, serum transforming growth factor‐beta 1 (TGF‐β1), and interleukin‐6 (IL‐6) concentration of the proximal femur were measured 1, 2, 4, and 8 weeks after treatment. Compared with the CT and DOP groups, the BMD and serum TGF‐β1 concentration in the PEMF group increased significantly after 8 weeks. The IL‐6 concentration in the DOP group was elevated significantly after operation. The PEMF group showed significantly lower IL‐6 level than the DOP group. The results found demonstrate that PEMF stimulation can efficiently suppress bone mass loss. We, therefore, conclude that PEMF may affect bone remodeling process through promoting TGF‐β1 secretion and inhibiting IL‐6 expression. Bioelectromagnetics 31:113–119, 2010. © 2009 Wiley‐Liss, Inc. 相似文献
936.
Sheng Peng Yan Zhang Jiannan Zhang Hua Wang Bingxu Ren 《Molecular biology reports》2010,37(7):3137-3142
To study the effects of ketamine on ERK expression in hippocampal neural cell and the ability of learning behavior in minor
rats. Seventy-two Sprague–Dawley rats of 21 days old were randomly divided into nine groups. The Y-maze was used to test the
ability of learning and spatial localization. At the end of training, all rats were killed and the expression levels of ERK1,
ERK2 and p-ERK1/2 were tested by immunohistochemistry. The learning times and total reaction time (TRT) of group K2a, K2b,
K2c and K3 have significant differences compared with T group (P < 0.05). Immunohistochemical staining showed that the level of ERK1, ERK2 and p-ERK1/2 in all rats which received light-electricity
integrated training increased remarkably relative to the C group (P < 0.01). The expression levels of ERK1, ERK2 and p-ERK1/2 in hippocampal neural cell of group K2a, K2b and K3 significantly
decreased when compared with T group (P < 0.05). Therefore, the results demonstrate that administration of over-anesthetic ketamine may impair learning ability of
21 days old rats within 24 h. ERK signal transduction pathway may be involved in the ability of learning and spatial localization.
The inhibition of ERK signal transduction pathway may be one of the mechanisms of the impairment of learning and memory ability
by ketamine. 相似文献
937.
The objectives of the present study were focused on detecting deletion mutation in bovine AMPD1 gene, and analyzing its effect on body measurement and carcass traits in Qinchuan cattle by using DNA sequencing and agarose electrophoresis methods. The 198-bp PCR products of AMPD1 gene exhibited three genotypes and two alleles were revealed: A and B. The frequencies of genotype AA/AB/BB in Qinchuan populations was 0.7163, 0.2233 and 0.0605. The χ2-test analysis demonstrated that the breed was not in agreement with Hardy–Weinberg equilibrium (P < 0.05). The association of the 18-bp deletion mutation of AMPD1 gene with body measurement and carcass traits of Qinchuan cattle were analyzed. The cattle with AA genotype had slaughter weight and carcass weight than those with genotype AB (P < 0.01 or P < 0.05). These results suggest that the 18-bp deletion mutation may influence the carcass traits in Qinchuan cattle. 相似文献
938.
939.
Feng Yan Xiaobei Deng Junpeng Yan Jiancheng Wang Lunguang Yao Songya lv Yipeng Qi Hua Xu 《Journal of microbiology (Seoul, Korea)》2010,48(2):199-205
The inhibitor of apoptosis proteins (IAP) plays an important role in cell apoptosis. We cloned two novel IAP family members,
Ap-iap1 and Ap-iap2, from Antheraea pernyi nucleopolyhedrovirus (ApNPV) genome. Ap-IAP1 contains two baculoviral IAP repeat (BIR) domains followed by a RING domain,
but Ap-IAP2 has only one BIR domain and RING. The result of transient expression in Spodoptera frugiperda (Sf21) showed that Ap-iap1 blocked cell apoptosis induced by actinomycin D treatment and also rescued the p35 deficient Autographa californica nucleopolyhedrovirus (AcNPV) to replicate in Sf9 cells, while Ap-iap2 does not have this function. Several Ap-IAP1 truncations were constructed to test the activity of BIRs or RING motif to inhibit
cell apoptosis. The results indicated that BIRs or RING of Ap-IAP1 had equally function to inhibit cell apoptosis. Therefore
deletion of above both of the above domains could not block apoptosis induced by actinomycin D or rescue the replication of
AcMNPVΔp35. We also screened two phage-display peptides that might interact with Ap-IAP1. 相似文献
940.
Yun-Shan Liang Xing-Zhong Yuan Guang-Ming Zeng Chen-Lu Hu Hua Zhong Dan-Lian Huang Lin Tang Jia-Jia Zhao 《Biodegradation》2010,21(4):615-624
Lignin degradation by white-rot fungi has received considerable attention as a means for reducing accumulation of lignocellulosic
wastes in the environment. The stimulatory effect of surfactants on fungal lignocellulose bioconversion also has attracted
wide interest. In this study the influence of dirhamnolipid biosurfactant on biodegradation of rice straw by Phanerochaete chrysosporium was investigated. It was shown that the biodelignification process of rice straw can be significantly enhanced by the presence
of dirhamnolipid biosurfactant. In particular, the dirhamnolipid at the concentration of 0.007% increased the peak activity
of lignin peroxidase (LiP) by 86% without affecting the manganese peroxidase (MnP) activity. The water-soluble organic carbon
(WSOC) contents in the straw substrates as well as the microbial growth and activity were effectively improved by dirhamnolipid,
while the degradation rate of lignin increased by 54% with dirhamnolipid of 0.007%. Observed chemical structural and morphological
changes showed that the straw substrates were delignified in the presence of dirhamnolipid with the formation of terrace-like
fragments separated from the inner cellular fibers and the release of simple compounds. Variation partitioning analysis revealed
that the dirhamnolipid addition induced a significant straw biodelignification which explained 22.1% (P = 0.013) of the variance. 相似文献