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981.
Dan Wang Jing Mao Bin Zhou Xiao-Fu Liao Shi-Qiang Gong Yan Liu Jing-Tao Zhang 《Biotechnology letters》2011,33(1):191-197
Purpose of work
Our study provides a promising alternative of biomimetic coating which functionalizes the dental implant with adhesion peptides and may be useful for enhancing the bone remodeling around Ti implants. 相似文献982.
In Pseudomonas aeruginosa, quorum sensing (QS) regulates dozens of genes and proteins, many of which contribute to the virulence of this pathogen.
QS inhibitory (QSI) compounds have been proposed as potential agents for treatment of bacterial infections. To search for
Ps. aeruginosa QS inhibitors, we constructed an effective screening system, QSIS-lasI selector, based on the PlasI-sacB reporter, in which QS could be induced with 20 nM 3-oxo-N-[(3S)-tetrahydro-2-oxo-3-furanyl]-dodecanamide (3-oxo-C12-HSL). During screening of the crude extracts from 65 marine fungi, an isolate of Penicillium atramentosum was found to have QSI activity. Thin-layer chromatography assay of the fungal extracts for bioautographic identification
of QSIS-lasI indicated that this fungus produced several QSI compounds, including QS inhibitors other than penicillic acid or patulin. 相似文献
983.
Evidence is accumulating that estradiol (E2) may play a dual role in carcinogenic and anticarcinogenic effects by different metabolic pathways. It has been shown that some metabolites of E2 exert proliferative and others anti-proliferative properties on human cancer cells. In the present study, the effects of E2 and its four primary metabolites including 2-hydroxyestradiol (2OHE2), 4-hydroxyestradiol (4OHE2), 2-methoxyestradiol (2ME), and 4-methoxyestradiol (4ME) on proliferation and cell cycle in RL95-2 human endometrial cells were investigated. Our results indicate that 2ME and 2OHE2, but not E2, 4ME, and 4OHE2, exhibit the inhibitory effect through cell cycle arrest at G2/M. 2ME and 2OHE2-induced G2/M cell cycle arrest associated with activation of p53 (Ser15), upregulation of p21(WAF1/Cip1) (p21) and GADD45, inactivation of Cdc2 (Tyr15), as well as downregulation of Cyclin B1. 2ME and 2OHE2-mediated cell cycle arrest at G2/M was also related to activation of protein kinase Chk1 which is associated with p53 (Ser20) activation and downstream responses. 相似文献
984.
985.
Min Fei Na Li Yuguan Ze Jie Liu Xiaolan Gong Yanmei Duan Xiaoyang Zhao Han Wang Fashui Hong 《Biological trace element research》2011,139(1):72-80
In order to study the mechanisms underlying the effects of lanthanoid (Ln) on the liver, ICR mice were injected with LaCl3, CeCl3, and NdCl3 at a dose of 20 mg/kg BW into the abdominal cavity daily for 14 days. We then examined oxidative stress-mediated responses
in the liver. The increase of lipid peroxide in the liver produced by Ln suggested an oxidative attack that was activated
by a reduction of antioxidative defense mechanisms as measured by analyzing the activities of superoxide dismutase, catalase,
and ascorbate peroxidase, as well as antioxidant levels such as glutathione and ascorbic acid, which were greatest in Ce3+ treatment, medium in Nd3+, and least in La3+. Our results also implied that the oxidative stress in the liver caused by Ln likely is Ce3+ > Nd3+ >La3+, but the mechanisms need to be further studied in future. 相似文献
986.
Jiu-Chang Zhong Jia-ying Ye Hai-yan Jin Xi Yu Hui-min Yu Ding-liang Zhu Ping-jin Gao Dong-yang Huang Manfred Shuster Hans Loibner Jun-min Guo Xi-yong Yu Bing-xiu Xiao Zhao-hui Gong Josef M. Penninger Gavin Y. Oudit 《Regulatory peptides》2011,166(1-3):90-97
Profilin-1 has recently been linked to vascular hypertrophy and remodeling. Here, we assessed the hypothesis that angiotensin (Ang) II type I receptor antagonist telmisartan improves vascular hypertrophy by modulation of expression of profilin-1 and angiotensin-converting enzyme 2 (ACE2). Ten-week-old male spontaneously hypertensive rats (SHR) were received oral administration of telmisartan (5 or 10 mg/kg; daily) or saline for 10 weeks. Compared with Wistar–Kyoto (WKY) rats, there were marked increases in systolic blood pressure and profilin-1 expression and reduced ACE2 and peroxisome proliferator activated receptor-γ (PPARγ) levels in aorta of SHR, associated with elevated extracellular-signal regulated kinase 1/2 (ERK1/2) and c-Jun N-terminal kinase (JNK) phosphorylation signaling and aortic hypertrophy characterized with increased media thickness, which were strikingly reversed by telmisartan. In cultured human umbilical artery smooth muscle cells (HUASMCs), Ang II induced a dose-dependent increase in profilin-1 expression, along with decreased ACE2 protein expression and elevated ERK1/2 and JNK phosphorylation. In addition, blockade of ERK1/2 or JNK by either specific inhibitor was able to abolish Ang II-induced ACE2 downregulation and profilin-1 upregulation in HUASMCs. Importantly, treatment with telmisartan (1 or 10 μM) or recombinant human ACE2 (2 mg/ml) largely ameliorated Ang II-induced profilin-1 expression and ERK1/2 and JNK phosphorylation and augmented PPARγ ?expression in the cultured HUASMCs. In conclusion, telmisartan treatment attenuates vascular hypertrophy in SHR by the modulation of ACE2 and profilin-1 expression with a marked reversal of ERK1/2 and JNK phosphorylation signaling pathways. 相似文献
987.
Aims
The multiple physiological characterizations of exendin-4 make it as a promising drug candidate for the therapy of type 2 diabetes. Although the longer biological half-life offered the exendin-4 with excellent therapeutic potentials for the clinical utility of type 2 diabetes than glucagon-like peptide-1, the exendin-4 still did not free from the inconveniently frequent injections. Therefore, there are increasing requirements for the long-acting exendin-4.Methods
Pp1 regard as a novel exendin-4 protecting peptide, which are predicted to have the ability of increasing the stabilization of exendin-4 in vivo. Protecting peptide is able to form stable complex by non-covalent interaction with human exendin-4.Results
In this study, the stability of the exendin-4/Pp1 complex was investigated, and the physiological functions of it were analyzed. Results indicated that exendin-4/Pp1 complex remarkably raised the stabilization of exendin-4 in vivo; it also showed better glucose tolerance and higher HbA1c reduction than exendin-4 which was utilized chronically in rodents.Conclusion
Based upon these results, it is suggested that an exendin-4/Pp1 complex might be utilized as a potent anti-diabetic drug in the treatment of type 2 diabetes mellitus. 相似文献988.
Peng X Gong F Xie G Zhao Y Tang M Yu L Tong A 《Molecular and cellular biochemistry》2011,351(1-2):233-241
This study aimed to explore the mechanism of adriamycin resistance in human chronic myelogenous leukemia cells. Proteomic approach was utilized to compare and identify differentially expressed proteins between human chronic myelogenous leukemia K562 cells and their adriamycin-resistant counterparts. The differentially expressed proteins were analyzed by 2-DE (two-dimensional gel electrophoresis), and protein identification were performed on ESI-Q-TOF MS/MS instrument. Out of the 35 differentially expressed proteins between the two cell lines, 29 were identified and grouped into 10 functional classes. Most of identified proteins were related to the categories of metabolism (24%), proteolysis (13%), signal transduction (21%) and calcium ion binding (6%), suggesting that alterations of those biological processes might be involved in adriamycin resistance of K562 cells. We believe this study may provide some clues to a better understanding of the molecular mechanisms underlying adriamycin resistance. 相似文献
989.
990.
Han N Shi Z Zhang K Gao X Zheng Z Gong P Guo Y Huang S Zhang F 《Cellular and molecular neurobiology》2011,31(5):695-700
Discs-large-related 3 (DLG3), a member of the membrane-associated guanylate kinases (MAGUKs) protein family, playing an important
role in regulating NMDA signal pathway and contributing to synaptic plasticity, may have an influence on the susceptibility
of non-syndromic mental retardation (NSMR). To investigate the possible genetic contribution of DLG3 gene to the NSMR of Chinese Han population, we performed an association study of 556 subjects (118 NSMR, 116 borderline NSMR,
and 322 controls in 275 males and 281 females) from Qin-Ba mountain region of Shaanxi province in the northwest of China by
five common SNPs in the gene. The results showed that there was no positive association between the genetic variations of
DLG3 and NSMR. In conclusion, the results of this study indicated that DLG3 did not associate with NSMR in Chinese Han population; however, further studies are needed. 相似文献