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11.
Endometriosis affects younger women of childbearing age. Atherosclerosis is considered as a disease of the old and increases with the ageing process. Both diseases are characterized by the increased presence of activated macrophages and associated increases in growth promoting activity and the production of inflammatory cytokines. In this review, we propose that oxidative stress and the presence of forms of oxidized low-density lipoprotein (LDL) might contribute to both Atherosclerosis and Endometriosis.  相似文献   
12.
Recently, emerging evidence has suggested that carcinoma-associated fibroblasts (CAFs) could contribute to chemotherapy resistances in breast cancer treatment. The aim of this study is to compare the gene expression profiling of CAFs before and after chemotherapy and pick up candidate genes that might associate with chemotherapy resistance and could be used as predictors of treatment response. CAFs were cultured from surgically resected primary breast cancers and identified with immunohistochemistry (IHC) and Flow cytometry (FCM). MDA-MB-231 cells were cultured as the breast cancer cell line. Cell adhesion assay, invasion assay, and proliferation assay (MTT) were performed to compare the function of MDA-MB-231 cells co-cultured with CAFs and MDA-MB-231 cells without co-culture, after chemotherapy. Totally 6 pairs of CAFs were prepared for microarray analysis. Each pair of CAFs were obtained from the same patient and classified into two groups. One group was treated with Taxotere (regarded as after chemotherapy) while the other group was not processed with Taxotere (regarded as before chemotherapy). According to our study, the primary-cultured CAFs exhibited characteristic phenotype. After chemotherapy, MDA-MB-231 cells co-cultured with CAFs displayed increasing adhesion, invasiveness and proliferation abilities, compared with MDA-MB-231 cells without CAFs. Moreover, 35 differentially expressed genes (absolute fold change >2) were identified between CAFs after chemotherapy and before chemotherapy, including 17 up-regulated genes and 18 down-regulated genes. CXCL2, MMP1, IL8, RARRES1, FGF1, and CXCR7 were picked up as the candidate markers, of which the differential expression in CAFs before and after chemotherapy was confirmed. The results indicate the changes of gene expression in CAFs induced by Taxotere treatment and propose the candidate markers that possibly associate with chemotherapy resistance in breast cancer.  相似文献   
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14.
Short cationic antimicrobial peptides (AMPs) are believed to act either by inducing transmembrane pores or disrupting membranes in a detergent-like manner. For example, the antimicrobial peptides aurein 1.2, citropin 1.1, maculatin 1.1 and caerin 1.1, despite being closely related, appear to act by fundamentally different mechanisms depending on their length. Using molecular dynamics simulations, the structural properties of these four peptides have been examined in solution as well as in a variety of membrane environments. It is shown that each of the peptides has a strong preference for binding to regions of high membrane curvature and that the structure of the peptides is dependent on the degree of local curvature. This suggests that the shorter peptides aurein 1.2 and citropin 1.1 act via a detergent-like mechanism because they can induce high local, but not long-range curvature, whereas the longer peptides maculatin 1.1 and caerin 1.1 require longer range curvature to fold and thus bind to and stabilize transmembrane pores.  相似文献   
15.
目的研究一种小分子多肽─APP5肽的模拟物P165对体外培养的大鼠胚胎海马神经干细胞(neuralstem cells,NSCs)增殖和分化的影响,以期能找到一种可代替神经营养因子的小分子物质,能够促进NSCs的增殖或分化,为将来的临床应用提供理论依据。方法(1)原代培养SD大鼠胚胎脑海马NSCs;(2)利用5-溴脱氧尿嘧啶核苷(BrdU)和神经元、星型胶质细胞、少突胶质细胞的特异性标记物微管相关蛋白2(MAP2)、胶质纤维酸性蛋白(GFAP)、2,3-环核苷酸-3磷酸二酯酶(CNPase)对培养的NSCs进行鉴定;(3)将培养的NSCs分为对照组、血清组、APP5肽反序列组和P165组,观察各组细胞形态的变化;(4)将培养的NSCs分为对照组、APP5肽反序列组和P165组,利用细胞计数,测定干细胞克隆形成率、干细胞克隆形成大小的方法分析P165对海马NSCs增殖的影响。结果(1)海马神经干细胞呈神经球聚集生长,BrdU染色阳性;加入血清后神经球周围有细胞呈放射状向四周生长,并带有突起。染色呈MAP2、GFAP或CNPase阳性;(2)海马NSCs加入P165及其反序列后细胞形态上与对照组相比没有明显改变;(3)与对照组相比,加P165后海马NSCs数量明显增加,克隆形成率和克隆形成的直径均有明显的增加,并有统计学差异。结论P165能够促进海马NSCs的增殖,但并不促进其分化。  相似文献   
16.
The large conductance, voltage- and Ca2+-activated potassium (MaxiK, BK) channel and caveolin-1 play important roles in regulating vascular contractility. Here, we hypothesized that the MaxiK alpha-subunit (Slo1) and caveolin-1 may interact with each other. Slo1 and caveolin-1 physiological association in native vascular tissue is strongly supported by (i) detergent-free purification of caveolin-1-rich domains demonstrating a pool of aortic Slo1 co-migrating with caveolin-1 to light density sucrose fractions, (ii) reverse co-immunoprecipitation, and (iii) double immunolabeling of freshly isolated myocytes revealing caveolin-1 and Slo1 proximity at the plasmalemma. In HEK293T cells, Slo1-caveolin-1 association was unaffected by the smooth muscle MaxiK beta1-subunit. Sequence analysis revealed two potential caveolin-binding motifs along the Slo1 C terminus, one equivalent, 1007YNMLCFGIY1015, and another mirror image, 537YTEYLSSAF545, to the consensus sequence, varphiXXXXvarphiXXvarphi. Deletion of 1007YNMLCFGIY1015 caused approximately 80% loss of Slo1-caveolin-1 association while preserving channel normal folding and overall Slo1 and caveolin-1 intracellular distribution patterns. 537YTEYLSSAF545 deletion had an insignificant dissociative effect. Interestingly, caveolin-1 coexpression reduced Slo1 surface and functional expression near 70% without affecting channel voltage sensitivity, and deletion of 1007YNMLCFGIY1015 motif obliterated channel surface expression. The results suggest 1007YNMLCFGIY1015 possible participation in Slo1 plasmalemmal targeting and demonstrate its role as a main mechanism for caveolin-1 association with Slo1 potentially serving a dual role: (i) maintaining channels in intracellular compartments downsizing their surface expression and/or (ii) serving as anchor of plasma membrane resident channels to caveolin-1-rich membranes. Because the caveolin-1 scaffolding domain is juxtamembrane, it is tempting to suggest that Slo1-caveolin-1 interaction facilitates the tethering of the Slo1 C-terminal end to the membrane.  相似文献   
17.
张蓉  冷允法  朱猛蒙  王芳 《应用生态学报》2007,18(11):2580-2585
运用地理信息系统(GIS)和地统计学方法对宁夏南部固原市原州区不同时期苜蓿斑蚜(Therioaphis trifolii)种群的空间结构进行了分析,并采用普通克立格插值法模拟了苜蓿斑蚜种群空间分布.结果表明:不同时期苜蓿斑蚜种群存在空间相关性,其半变异函数曲线均为指数型,空间格局呈聚集分布,空间变异成分的变化范围为34.13%~48.77%,空间相关范围为8.751~12.049km,聚集程度和方向有从西南向东北方向聚集的趋势.空间分布模拟图能较好地从时间、空间两个角度直观地分析不同时期苜蓿斑蚜种群的动态变化,易于确定同一时期苜蓿斑蚜的发生位置和发生程度.  相似文献   
18.
Twelve groups of fossils, including graptolites, brachiopods, nautiloids, trilobites, corals, crinoids, bryozoans, conodonts, ostracods, gastropods, chitinozoans, and acritarchs expired in different but substantial magnitude and global extent during the late Caradoc to latest Ashgill. It indicates a multiple‐episodic mass extinction containing the possible Prologue (late Caradoc), Climax episode (Rawtheyan) and Epilogue (late Hirnantian). The main causes of this mass extinction are recognized as a global sea‐level lowering in the climax and remarkable rapid rise at the final, and global cooling. The Chinese data, especially from the South China Paleoplate, are evaluated first. They are significant for explaining this global bioevent.  相似文献   
19.
FASN plays an important role in the malignant phenotype of various tumors. Our previous studies show that inhibition FASN could induce apoptosis and inhibit proliferation in human osteosarcoma (OS) cell in vivo and vitro. The aim in this study was to investigate the effect of inhibition FASN on the activity of HER2/PI3K/AKT axis and invasion and migration of OS cell. The expression of FASN, HER2 and p-HER2(Y1248) proteins was detected by immunohistochemistry in OS tissues from 24 patients with pulmonary metastatic disease, and the relationship between FASN and p-HER2 as well as HER2 was investigated. The results showed that there was a positive correlation between FASN and HER2 as well as p-HER2 protein expression. The U-2 OS cells were transfected with either the FASN specific RNAi plasmid or the negative control RNAi plasmid. FASN mRNA was measured by RT-PCR. Western blot assays was performed to examine the protein expression of FASN, HER2, p-HER2(Y1248), PI3K, Akt and p-Akt (Ser473). Migration and invasion of cells were investigated by wound healing and transwell invasion assays. The results showed that the activity of HER2/PI3K/AKT signaling pathway was suppressed by inhibiting FASN. Meanwhile, the U-2OS cells migration and invasion were also impaired by inhibiting the activity of FASN/HER2/PI3K/AKT. Our results indicated that inhibition of FASN suppresses OS cell invasion and migration via down-regulation of the “HER2/PI3K/AKT” axis in vitro. FASN blocker may be a new therapeutic strategy in OS management.  相似文献   
20.
As an important organic compound, chiral alcohols are the key chiral building blocks to many single enantiomer pharmaceuticals. Asymmetric reduction of the corresponding prochiral ketones to produce the chiral alcohols by biocatalysis is one of the most promising routes. Asymmetric reduction of different kinds of non-natural prochiral ketones catalyzed by various plants tissue was studied in this work. Acetophenone, 4'-chloroacetophenone and ethyl 4-chloroacetoacetate were chosen as the model substrates for simple ketone, halogen-containing aromatic ketone and beta-ketoesters, respectively. Apple (Malus pumila), carrot (Daucus carota), cucumber (Cucumis sativus), onion (Allium cepa), potato (Soanum tuberosum), radish (Raphanus sativus) and sweet potato (Ipomoea batatas) were chosen as the biocatalysts. It was found that these kinds of prochiral ketoness could be reduced by these plants tissue with high enantioselectivity. Both R- and S-form configuration chiral alcohols could be obtained. The e.e. and chemical yield could reach about 98 and 80% respectively for acetophenone and 4'-chloroacetophenone reduction reaction with favorable plant tissue. And the e.e. and yield for ethyl 4-chloroacetoacetate reduction reaction was about 91 and 45% respectively.  相似文献   
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