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181.
Background
Non-ionizing radiation imaging assessment has been advocated for the patients with adolescent idiopathic scoliosis (AIS). As one of the radiation-free methods, ultrasound imaging has gained growing attention in scoliosis assessment over the past decade. The center of laminae (COL) method has been proposed to measure the spinal curvature in the coronal plane of ultrasound image. However, the reliability and validity of this ultrasound method have not been validated in the clinical setting.Objectives
To evaluate the reliability and validity of clinical ultrasound imaging on lateral curvature measurements of AIS with their corresponding magnetic resonance imaging (MRI) measurements.Methods
Thirty curves (ranged 10.2°–68.2°) from sixteen patients with AIS were eligible for this study. The ultrasound scan was performed using a 3-D ultrasound unit within the same morning of MRI examination. Two researchers were involved in data collection of these two examinations. The COL method was used to measure the coronal curvature in ultrasound image, compared with the Cobb method in MRI. The intra- and inter-rater reliability of the COL method was evaluated by intra-class correlation coefficient (ICC). The validity of this method was analyzed by paired Student’s t-test, Bland–Altman statistics and Pearson correlation coefficient. The level of significance was set as 0.05.Results
The COL method showed high intra- and inter-rater reliabilities (both with ICC (2, K) >0.9, p<0.05) to measure the coronal curvature. Compared with Cobb method, COL method showed no significant difference (p<0.05) when measuring coronal curvature. Furthermore, Bland-Altman method demonstrated an agreement between these two methods, and Pearson’s correlation coefficient (r) was high (r>0.9, p<0.05).Conclusion
The ultrasound imaging could provide a reliable and valid measurement of spinal curvature in the coronal plane using the COL method. Further research is needed to validate the proposed ultrasound measurement in larger clinical trial and to optimize the ultrasound scanning and measuring procedure. 相似文献182.
Jasmin Strotmeier Stefan Mahrhold Nadja Krez Constantin Janzen Jianlong Lou James D. Marks Thomas Binz Andreas Rummel 《FEBS letters》2014
Botulinum neurotoxins (BoNTs) inhibit neurotransmitter release by hydrolysing SNARE proteins. The most important serotype BoNT/A employs the synaptic vesicle glycoprotein 2 (SV2) isoforms A-C as neuronal receptors. Here, we identified their binding site by blocking SV2 interaction using monoclonal antibodies with characterised epitopes within the cell binding domain (HC). The site is located on the backside of the conserved ganglioside binding pocket at the interface of the HCC and HCN subdomains. The dimension of the binding pocket was characterised in detail by site directed mutagenesis allowing the development of potent inhibitors as well as modifying receptor binding properties. 相似文献
183.
184.
Xiaoyong Dai Cuizan Cai Fei Xiao Yaoling Xiong Yadong Huang Qihao Zhang Qi Xiang Guofeng Lou Mengyang Lian Zhijian Su Qing Zheng 《Biochemical and biophysical research communications》2014
It has been reported that acidic fibroblast growth factor (aFGF) is expressed in breast cancer and via interactions with fibroblast growth factor receptors (FGFRs) to promote the stage and grade of the disease. Thus, aFGF/FGFRs have been considered essential targets in breast cancer therapy. We identified a specific aFGF-binding peptide (AGNWTPI, named AP8) from a phage display heptapeptide library with aFGF after four rounds of biopanning. The peptide AP8 contained two (TP) amino acids identical and showed high homology to the peptides of the 182–188 (GTPNPTL) site of high-affinity aFGF receptor FGFR1. Functional analyses indicated that AP8 specifically competed with the corresponding phage clone A8 for binding to aFGF. In addition, AP8 could inhibit aFGF-stimulated cell proliferation, arrested the cell cycle at the G0/G1 phase by increasing PA2G4 and suppressing Cyclin D1 and PCNA, and blocked the aFGF-induced activation of Erk1/2 and Akt kinase in both breast cancer cells and vascular endothelial cells. Therefore, these results indicate that peptide AP8, acting as an aFGF antagonist, is a promising therapeutic agent for the treatment of breast cancer. 相似文献
185.
186.
Huiqing Yuan Charles Y. F. Young Yuanyuan Tian Zhifang Liu Mengye Zhang Hongxiang Lou 《Molecular and cellular biochemistry》2010,339(1-2):253-262
We have previously reported that the increase in c-Jun expression induced by quercetin inhibited androgen receptor (AR) transactivation, and Sp1 was involved in quercetin-mediated downregulation of AR activity. Transient transfection assays in this work revealed that co-expression of c-Jun quenched Sp1-induced production of luciferase activity driven by AR promoter or three copies of Sp1 binding elements in the AR promoter. Moreover, c-Jun repressed AR-mediated luciferase activity via androgen-response elements (AREs) of the hK2 gene, while this suppression could be restored partially by cotransfection of Sp1 expression plasmid. The physical associations of c-Jun, Sp1, and AR induced by quercetin were further demonstrated by co-immunoprecipitation experiments. In addition, quercetin-mediated repression of AR expression and activity was partially reversed by blocking of JNK signaling pathway. These results suggested that c-Jun might play an important role in the suppression of AR expression and activity in the presence of quercetin, and association of a c-Jun/Sp1/AR protein complex induced by quercetin represented a novel mechanism that was involved in down-regulation of the AR function in prostate cancer cells. 相似文献
187.
Lou N Wang Y Sun D Zhao J Wang Y Gao Z 《Indian journal of biochemistry & biophysics》2010,47(6):340-347
To isolate stem-like cells from the human MG-63 osteosarcoma cell line, different subpopulations of MG-63 cells were cloned by limiting dilution and passaged to obtain different sublines. The subline with highest clonogenicity was identified using a proliferation assay, cell-cycle analysis, and soft-agar colony-forming assay. The sublines were further selected in serum-free medium containing 20 ng/ml vincristine to identify cells that could form suspended sarcospheres. Identified cells were then characterized based on morphology, cell surface markers, adipogenic and osteogenic differentiation, and tumorigenicity in nude mice. A total of 19 holoclones that could be stably passaged were obtained. Sublines A1, A3, and D1 were markedly different from other sublines and the parental cell line. Subline D1 not only had a higher colony-forming efficiency and formed larger colonies, but also possessed a shorter latency of tumorigenesis in vivo. After subline D1 was cultured in suspension in medium containing vincristine, a highly enriched subpopulation of cells that could form sarcospheres and be stably passaged were obtained. These cells, designated as MG-63-M expressed multiple markers of multipotent or embryonic stem cells and possessed the capacity for self-renewal, multilineage differentiation, and significant multi-drug resistance. Thus, our results suggest that a subpopulation of stem-like cells can be isolated from human MG-63 osteosarcoma cell line. 相似文献
188.
Wastewater treatment performance of a vermifilter enhancement by a converter slag–coal cinder filter
The study aimed at investigating rural domestic wastewater treatment performance through vermifilter enhancement by a converter slag–coal cinder filter. The research was carried out by column experiments in a lab scale. Results showed the average removal rate of TCOD, BOD, ammonia nitrogen (NH4+-N) and phosphorus removal by the system were 78.0%, 98.4%, 90.3%, 62.4%, respectively at a hydraulic loading rate of 4 m3 m?2 day?1. Vermifiltration was effective for insoluble organic matter and suspended solid removal, and the converter slag–coal cinder filter played an important role in phosphorus removal. The molecular weight of particles in the influent and effluents from every unit of the system were distributed in a wide range between 0.1 kDa and 10,000 kDa with predominance of values between 10 kDa and 300 kDa; the major portion of soluble material are high MW compounds. In addition, the optimal design parameters for vermifiltration and converter slag and coal cinder filters, respectively, were studied in the experiments. 相似文献
189.
Yan-Ru Lou Ferdinand Molnár Mikael Peräkylä Shengjun Qiao Allan V. Kalueff René St-Arnaud Carsten Carlberg Pentti Tuohimaa 《The Journal of steroid biochemistry and molecular biology》2010,118(3):162-170
25-Hydroxyvitamin D3 1α-hydroxylase encoded by CYP27B1 converts 25-hydroxyvitamin D3 into 1α,25-dihydroxyvitamin D3, a vitamin D receptor ligand. 25-Hydroxyvitamin D3 has been regarded as a prohormone. Using Cyp27b1 knockout cells and a 1α-hydroxylase-specific inhibitor we provide in four cellular systems, primary mouse kidney, skin, prostate cells and human MCF-7 breast cancer cells, evidence that 25-hydroxyvitamin D3 has direct gene regulatory properties. The high expression of megalin, involved in 25-hydroxyvitamin D3 internalisation, in Cyp27b1?/? cells explains their higher sensitivity to 25-hydroxyvitamin D3. 25-Hydroxyvitamin D3 action depends on the vitamin D receptor signalling supported by the unresponsiveness of the vitamin D receptor knockout cells. Molecular dynamics simulations show the identical binding mode for both 25-hydroxyvitamin D3 and 1α,25-dihydroxyvitamin D3 with the larger volume of the ligand-binding pocket for 25-hydroxyvitamin D3. Furthermore, we demonstrate direct anti-proliferative effects of 25-hydroxyvitamin D3 in human LNCaP prostate cancer cells. The synergistic effect of 25-hydroxyvitamin D3 with 1α,25-dihydroxyvitamin D3 in Cyp27b1?/? cells further demonstrates the agonistic action of 25-hydroxyvitamin D3 and suggests that a synergism between 25-hydroxyvitamin D3 and 1α,25-dihydroxyvitamin D3 might be physiologically important. In conclusion, 25-hydroxyvitamin D3 is an agonistic vitamin D receptor ligand with gene regulatory and anti-proliferative properties. 相似文献
190.
OsZIP5 is a plasma membrane zinc transporter in rice 总被引:1,自引:0,他引:1
Sichul Lee Hee Joong Jeong Sun A. Kim Joohyun Lee Mary Lou Guerinot Gynheung An 《Plant molecular biology》2010,73(4-5):507-517
Zinc is essential for normal plant growth and development. To understand its transport in rice, we characterized OsZIP5, which is inducible under Zn deficiency. OsZIP5 complemented the growth defect of a yeast Zn-uptake mutant, indicating that OsZIP5 is a Zn transporter. The OsZIP5-GFP fusion protein was localized to the plasma membrane. Transgenic plants overexpressing the gene grew less well. Overexpression of the gene decreased the Zn concentration in shoots, but caused it to rise in the roots. Knockout plants showed no visible phenotypic changes under either normal or deficient conditions. However, they were tolerant to excess Zn and contained less Zn. In contrast, overexpressing transgenics were sensitive to excess Zn. These results indicate that OsZIP5 plays a role in Zn distribution within rice. 相似文献