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Xinglei Yao Na Zhou Li Wan Xiaodong Su Zhao Sun Hiroyuki Mizuguchi Yasuo Yoshioka Shinsaku Nakagawa Robert Chunhua Zhao Jian-Qing Gao 《Biochemical and biophysical research communications》2014
Mesenchymal stem cells (MSCs) are non-hematopoietic cells with multi-lineage potential, which makes them attractive targets for regenerative medicine applications. Efficient gene transfer into MSCs is essential for basic research in developmental biology and for therapeutic applications involving gene-modification in regenerative medicine. Adenovirus vectors (Advs) can efficiently and transiently introduce an exogenous gene into many cell types via their primary receptors, the coxsackievirus and adenovirus receptors (CARs), but not into MSCs, which lack CAR expression. To overcome this problem, an Adv coated with cationic polymer polyethyleneimine (PEI) was developed. In this study, we demonstrated that PEI coating with an optimal ratio can enhance adenoviral transduction of MSCs without cytotoxicity. We also investigated the physicochemical properties and internalization mechanisms of the PEI-coated Adv. These results could help to evaluate the potentiality of the PEI-coated Adv as a prototype vector for efficient and safe transduction into MSCs. 相似文献
3.
A Gram-stain negative, motile, rod-shaped bacterium, designated strain WM-2T, was isolated from a forest soil in Sihui City, South China, and characterized by means of a polyphasic approach. Growth occurred with 0–5 % (w/v) NaCl (optimum 0–1 %) and at pH 5.0–10.5 (optimum pH 8.5) and 4–40 °C (optimum 30 °C) in Luria–Bertani medium. Comparative 16S rRNA gene sequence analyses showed that strain WM-2T is a member of the genus Pseudomonas and most closely related to P. guguanensis, P. oleovorans subsp. lubricantis, P. toyotomiensis, P. alcaliphila and P. mendocina with 97.1–96.6 % sequence similarities. In terms of gyrB and rpoB gene sequences, strain WM-2T showed the highest similarity with the type strains of the species P. toyotomiensis and P. alcaliphila. The DNA–DNA relatedness values of strain WM-2T with P. guguanensis and P. oleovorans subsp. lubricantis was 48.7 and 37.2 %, respectively. Chemotaxonomic characteristics (the main ubiquinone Q-9, major fatty acids C18:1 ω7c/C18:1 ω6c, C16:0 and C16:1 ω7c/C16:1 ω6c and DNA G+C content 65.2 ± 0.7 mol%) were similar to those of members of the genus Pseudomonas. Polar lipids consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, an unknown aminophospholipid, an unknown phospholipid and five unknown lipids. According to the results of polyphasic analyses, strain WM-2T represents a novel species in the genus Pseudomonas, for which the name Pseudomonas sihuiensis sp. nov. is proposed. The type strain is WM-2T (=KCTC 32246T=CGMCC 1.12407T). 相似文献
4.
Our previous study reported that cerebrosides from traditional Chinese medicine Baifuzi directly interact with the STREX domain of BKCa channels, which in turn results in the therapeutic effect of Baifuzi on ischemic stroke. However, it is not known how cerebrosides in the plasma membrane could interact with the STREX domain that is in the cytoplasmic side. Using patch-clamp technique, effects of different cerebrosides on the BKCa channel were studied by measuring single channel currents in CHO cells expressing wild type or mutated BKCa channels. Palmitoylation of the STREX domain was removed either by site-directed mutagenesis or pharmacological inhibition. Removal of palmitoylation sites at C646 and C647 by mutating the residues to Ala abolished the ability of cerebrosides to activate the BKCa channel. In contrast, the mutation neither changed the single channel conductance nor voltage sensitivity of the channel. Both palmitoylation inhibitors tunicamycin and palmitic acid analog 2-bromopalmitate attenuated the activation of the BKCa channel by cerebrosides. Furthermore, confocal images on STREX-EGFP fragments demonstrated that STREX fragments no longer associated with the plasma membrane when the palmitoylation was removed or blocked. These findings suggest that palmitoylation of the STREX domain is necessary for cerebrosides to activate the BKCa channel and provide insight into the mechanism of how Baifuzi could exert therapeutic effect on ischemic stroke. 相似文献
5.
Background
Carpal tunnel syndrome is common among employed persons. Data on sickness absence from work in relation to carpal tunnel syndrome have been usually based on self-report and derived from clinical or occupational populations. We aimed to determine sickness absence among persons with physician-diagnosed carpal tunnel syndrome as compared to the general population.Methods
In Skåne region in Sweden we identified all subjects, aged 17–57 years, with new physician-made diagnosis of carpal tunnel syndrome during 5 years (2004–2008). For each subject we randomly sampled, from the general population, 4 matched reference subjects without carpal tunnel syndrome; the two cohorts comprised 5456 and 21,667 subjects, respectively (73% women; mean age 43 years). We retrieved social insurance register data on all sickness absence periods longer than 2 weeks from 12 months before to 24 months after diagnosis. Of those with carpal tunnel syndrome 2111 women (53%) and 710 men (48%) underwent surgery within 24 months of diagnosis. We compared all-cause sickness absence and analyzed sickness absence in conjunction with diagnosis and surgery.Results
Mean number of all-cause sickness absence days per each 30-day period from 12 months before to 24 months after diagnosis was significantly higher in the carpal tunnel syndrome than in the reference cohort. A new sickness absence period longer than 2 weeks in conjunction with diagnosis was recorded in 12% of the women (n = 492) and 11% of the men (n = 170) and with surgery in 53% (n = 1121) and 58% (n = 408) of the surgically treated, respectively; median duration in conjunction with surgery was 35 days (IQR 27–45) for women and 41 days (IQR 28–50) for men.Conclusions
Persons with physician-diagnosed carpal tunnel syndrome have substantially more sickness absence from work than age and sex-matched persons from the general population from1 year before to 2 years after diagnosis. Gender differences were small. 相似文献6.
KPC-producing Klebsiella pneumoniae isolates have emerged as important pathogens of nosocomial infections, and tigecycline is one of the antibiotics recommended for severe infections caused by KPC-producing K. pneumoniae. To identify the susceptibility profile of KPC-producing K. pneumoniae to tigecycline and investigate the role of efflux pumps in tigecycline resistance, a total of 215 KPC-producing K. pneumoniae isolates were collected. The minimum inhibitory concentration (MIC) of tigecycline was determined by standard broth microdilution tests. Isolates showing resistance to tigecycline underwent susceptibility test with efflux pump inhibitors. Expression levels of efflux pump genes (acrB and oqxB) and their regulators (ramA, marA, soxS and rarA) were examined by real-time PCR, and the correlation between tigecycline MICs and gene expression levels were analysed. Our results show that the tigecycline resistance rate in these isolates was 11.2%. Exposure of the tigecycline-resistant isolates to the efflux pump inhibitor NMP resulted in an obvious decrease in MICs and restored susceptibility to tigecycline in 91.7% of the isolates. A statistically significant association between acrB expression and tigecycline MICs was observed, and overexpression of ramA was found in three tigecycline-resistant isolates, further analysis confirmed ramR mutations existed in these isolates. Transformation of one mutant with wild-type ramR restored susceptibility to tigecycline and repressed overexpression of ramA and acrB. These data indicate that efflux pump AcrAB, which can be up-regulated by ramR mutations and subsequent ramA activation, contributed to tigecycline resistance in K. pneumoniae clinical isolates. 相似文献
7.
Yujie Zhang Chengzhen Liang Yiqing Tao Xiaopeng Zhou Hao Li Fangcai Li Qixin Chen 《PloS one》2015,10(3)
Background
Despite being considered the standard surgical procedure for symptomatic cervical disc disease, anterior cervical decompression and fusion invariably accelerates adjacent segment degeneration. Cervical total disc replacement is a motion-preserving procedure developed as a substitute to fusion. Whether cervical total disc replacement is superior to fusion remains unclear.Methods
We comprehensively searched PubMed, EMBASE, Medline, and the Cochrane Library in accordance with the inclusion criteria to identify possible studies. The retrieved results were last updated on December 12, 2014. We classified the studies as short-term and midterm follow-up.Results
Nineteen randomized controlled trials involving 4516 cases were identified. Compared with anterior cervical decompression and fusion, cervical total disc replacement had better functional outcomes (neck disability index [NDI], NDI success, neurological success, neck pain scores reported on a numerical rating scale [NRS], visual analog scales scores and overall success), greater segmental motion at the index level, fewer adverse events and fewer secondary surgical procedures at the index and adjacent levels in short-term follow-up (P < 0.05). With midterm follow-up, the cervical total disc replacement group indicated superiority in the NDI, neurological success, pain assessment (NRS), and secondary surgical procedures at the index level (P < 0.05). The Short Form 36 (SF-36) and segmental motion at the adjacent level in the short-term follow-up showed no significant difference between the two procedures, as did the secondary surgical procedure rates at the adjacent level with midterm follow-up (P > 0.05).Conclusions
Cervical total disc replacement presented favorable functional outcomes, fewer adverse events, and fewer secondary surgical procedures. The efficacy and safety of cervical total disc replacement are superior to those of fusion. Longer-term, multicenter studies are required for a better evaluation of the long-term efficacy and safety of the two procedures. 相似文献8.
Genome‐wide analysis identifies an african‐specific variant in SEMA4D associated with body mass index 下载免费PDF全文
Jie Zhou Lin Lei Amy R. Bentley Fasil Tekola-Ayele Sally N. Adebamowo Jennifer L. Baker Olufemi Fasanmade Godfrey Okafor Benjamin Eghan Jr. Kofi Agyenim‐Boateng Albert Amoah Clement Adebamowo Joseph Acheampong Thomas Johnson Johnnie Oli Daniel Shriner Adebowale A. Adeyemo Charles N. Rotimi 《Obesity (Silver Spring, Md.)》2017,25(4):794-800
9.
Solar Cells: Synergic Interface Optimization with Green Solvent Engineering in Mixed Perovskite Solar Cells (Adv. Energy Mater. 20/2017) 下载免费PDF全文
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