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11.
《Sleep medicine》2020
BackgroundThe peripheral level of matrix metalloproteinase (MMP)-9 and polymorphism of MMP9 -1562C>T in patients with obstructive sleep apnea (OSA) remains controversial. Therefore, the aims of this systemic review and meta-analysis are to assess the MMP9 level in OSA patients and identify the relationship between MMP9 -1562C>T and OSA susceptibility.MethodsThis systematic review was performed following the PRISMA guideline. We searched for studies in major databases, identifying those indexed from inception to July 3, 2019 which related to MMP9 level, MMP9 -1562C>T and OSA. The pooled standardized mean differences (SMDs) and 95% confidence interval (CI) of MMP9 levels were calculated. In addition, the relationship between MMP9 -1562C>T and OSA susceptibility was assessed by three genetic models. The heterogeneity analysis and calculation of the pooled odds ratio (OR) were also performed, followed by quality assessment using the Newcastle-Ottawa Scale (NOS).ResultsIn sum, our review included 15 eligible studies regarding MMP9 level and three regarding MMP9 -1562C>T. The pooled results showed that peripheral level of MMP9 was increased in OSA patients (SMD = 1.37; 95% CI = 1.15–1.59). Furthermore, significant difference of MMP9 level can be found between severe and mild-to-moderate OSA patients (SMD = 28.17; 95% CI = 4.23–52.11) or between moderate-severe and mild OSA (SMD = 36.62; 95% CI = 12.19–61.04). However, no relationship was observed between MMP9 -1562C>T and OSA susceptibility in three genetic models (Homozygote model, OR = 1.37; 95% CI = 0.87–2.18); (Recessive model, OR = 1.42; 95% CI = 0.83–2.42); (Allele model, OR = 1.07; 95% CI = 0.96–1.18).ConclusionsThis systemic review and meta-analysis indicated that the level of MMP9 was increased in patients with OSA and this increase is relevant to OSA severity. Moreover, the relationship between MMP9 -1562 C>T and OSA susceptibility has currently not been proven by current merging values. Further analyses with larger sample size are required to verify these associations. 相似文献
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目的研究Ets-1、基质金属蛋白酶1(MMP-1)及基质金属蛋白酶1抑制物(TIMP-1)在膀胱移行细胞癌(BTCC)中的表达及意义。方法用免疫组化方法检测40例BTCC组织和12例正常膀胱黏膜组织中Ets-1、MMP-1及TIMP-1的表达;分析Ets-1与BTCC临床病理特征间的关系;研究BTCC中MMP-1、TIMP-1表达与Ets-1表达的相关性。结果①Ets-1在BTCC中高度表达,阳性率为82.5%(P<0.01),且随BTCC临床分期和病理分级的升高而增加,肿瘤复发组高于无复发组,肿瘤转移组高于无转移组(P<0.05)。②MMP-1阳性表达率膀胱癌组(85.0%)明显高于对照组(58.3%)(p<0.05);TIMP-1阳性表达率对照组(83.3%)明显高于膀胱癌组(47.5%)(P<0.05)。③MMP-1与Ets-1表达呈正相关(Rs为0.824,P<0.01),而TIMP-1与Ets-1表达呈负相关(Rs为-0.821,P<0.01)。结论①Ets-1在BTCC中高度表达,并随BTCC分期分级升高而增加;Ets-1与BTCC转移及复发密切相关。②BTCC中Ets-1上调MMP-1表达,而下调TIMP-1表达,从而参与BTCC侵袭与转移。 相似文献
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15.
A variant of the HL-60 cell line, HL-60/MCSFR4D2, has been found to express twice the amount of PTP1C as compared to the parental HL-60 cell line by immunoblotting and immunoprecipitation. Differentiation of the variant cells after phorbol 12-myristate 13-acetate (PMA) treatment was examined by the appearance of adherence. In 1% fetal calf serum (FCS), 20% of HL-60/MCSFR4D2 cells exhibited adherence after treatment with 0.5 ng/ml PMA for 48 h, 60% exhibited adherence after treatment with 1.0 ng/ml PMA and 80% exhibited adherence after treatment with 5.0 ng/ml PMA, while HL-60 cells exhibited only a slight response. Furthermore, antisense PTP1C oligonucleotides decreased the PMA-induced adherence of HL-60/MCSFR4D2 cells. These results suggest that the high-expression of PTP1C in HL-60 cells may be involved in the enhancement of susceptibility to macrophage-like differentiation by PMA. 相似文献
16.
Martha A. Warpehoski Paul J. Buscemi David C. Osborn Birdwell Finlayson Eugene P. Goldberg 《Calcified tissue international》1981,33(1):211-222
Summary The quantity of protein and carbohydrate comprising the matrix of calcium oxalate monohydrate (COM) renal stones was found
to decrease with distance from the surface of the stone. The average organic concentration of stones 3 to 30 mm in diameter
ranged from 5.7% at the surface to 2.7% at the core. This concentration gradient suggests matrix involvement in a “growth
front” on stone surfaces with migration of organic material from the “older” interior. The matrix distribution was not readily
correlated with density variations or with the presence of hydroxyapatite or calcium oxalate dihydrate. Surface matrix concentrations
were greater than amounts predicted by physical adsorption. Electron microscopy confirmed the presence of the organic-rich
surface layer and also suggested that increase in stone size occurs predominantly by crystal growth with microcrystal aggregates
as growth centers. 相似文献
17.
GIUSEPPE PERSEO MAURO GIGLI ROBERTO DE CASTIGLIONE 《Chemical biology & drug design》1987,29(4):478-485
The synthesis of TPH-13 (Glp-Glu-Lys-Pro-Tyr-Trp-Pro-Pro-Pro-Ile-Tyr-Pro-Met-OH), a tridecapeptide isolated from the skin of the South American frog Phyllomedusa rohdei, is described and alternative approaches are discussed. 相似文献
18.
目的 构建大鼠MMP1 3重组腺病毒载体。方法 将MMP1 3cDNA目的片段插入腺病毒柯氏质粒中 ,再将此质粒与腺病毒DNA末端蛋白复合物共转染 2 93细胞 ,通过同源重组构建MMP1 3 重组腺病毒载体。结果 MMP1 3 重组腺病毒载体经PCR鉴定正确 ,包装纯化后 ,检测病毒滴度为 4× 1 0 9PFU/ml。结论 成功地构建了RatMMP1 3 重组腺病毒载体 ,为下一步行MMP 1 3转基因治疗低顺应性膀胱的研究提供了条件 相似文献
19.
3-(3-吡啶基)-6-芳基-7H-1,2,4-三唑并[3,4-b][1,3,4]噻二嗪的合成与波谱表征 总被引:2,自引:0,他引:2
目的:研究分子中含吡啶基的有多个杂环的化合物系列的波谱表征,方法:由烟酸出发,经多步反应,制得有吡啶基的均三唑并噻二嗪化合物,并进行红外,核磁共振氢谱与碳谱测试。结果:得到原料,中间体和产物的红外光谱图,产物的核磁共振氢谱与碳谱图。结论:标题化合物红外光谱1600cm^-1处多有C=N伸缩振动峰,1250cm^-左右有N-N=C伸缩振动峰,700cm^-1有C-S-C弯曲振动峰;噻二嗪亚甲基氢的化学位移δ值约为4.46,吡啶基四个氢原子化学位移约为9.3、8.9、8.7、8.0,噻二嗪亚甲基碳化学位移为23。 相似文献
20.
目的探讨基质金属蛋白酶-2(matrix metalloproteinase-2,MMP-2)和环氧合酶-2(cyclooxygenase.2,COX.2)蛋白在非小细胞肺癌组织中的表达与意义。方法应用免疫组化SP方法检测80例非小细胞肺癌组织中MMP-2,COX-2的表达。结果MMP2及COX-2的阳性率分别为31.25%、41.25%。MMP-2及COX-2蛋白表达与临床病理因素无相关性。MMP2和COX-2的阳性表达之间无相关性。结论MMP2及COX-2参与非小细胞肺癌的发生,然而它们也许并不能作为重要的预后指标。 相似文献