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31.
32.
Objective To observe the expression of Klotho and Na+/Pi cotransporter in high phosphorous-induced rats with 5/6 nephrectomy and its relationship with vascular calcification, as well as to investigate the effect of early intervention by sodium thiosulfate (STS) on the progression of vascular calcification. Methods Either 5/6 nephrectomy (n=21) or sham operation (n=14) was conducted on 35 Sprague Dawley rats, who were then fed with high phosphorus (HP) diet or normal phosphorus (NP) diet for 16 weeks respectively. The rats were divided into 5 groups as follows: (1) remnant kidney rats receiving HP diet (NHP, n=7), (2) remnant kidney rats receiving NP diet (NNP, n=7), (3) sham operation rats receiving NP diet (SNP, n=7), (4) sham operation rats receiving HP diet (SHP, n=7), (5) remnant kidney rats receiving HP diet with STS (THP, n=7). The treatment group was given STS intraperitoneally three times a week for 16 weeks. At the end of the 16th week, rats tail artery blood pressures were tested, serum creatinine (Scr), calcium (Ca2+), phosphorus (P3+), FGF23, iPTH and urine protein were examined. Throacic aorta and kidney were then removed. Vascular calcification was confirmed by Von kossa staining. Klotho and Pit-1 expression in aortas were determined by immunohistochemistry. Renal lesion was determined by PASM-Masson staining. Renal Klotho and NaPi-2a mRNA were determined by real time RT-PCR. Results After 16 weeks, Scr, P3+, FGF23, iPTH, uric protein and blood pressure were significantly higher in NHP than those in SNP rats (all P<0.05). PASM-Masson staining revealed typical renal pathology of chronic renal failure in NHP group. With the treatment of STS, THP rats showed significant decrease in Scr, P3+, FGF23, iPTH, uric protein and blood pressure by comparison with NHP group (all P<0.05). Significant vascular calcification was found in NHP group while NNP and SHP group occasionally had vascular calcification; THP group had marked alleviation of vascular calcification. The aorta and renal expression of Klotho decreased remarkably while expression of Pit-1 and NaPi-2a increased significantly in NHP compared with SNP group (all P<0.05). Accordingly, the aorta and renal expression of Klotho increased and Pit-1 and NaPi-2a decreased significantly in THP compared with NHP group (P<0.05). Conclusions The early intervention of sodium thiosulfate might regulate Klotho and Na+/Pi cotransporter expression in both aorth and kidney, decreasing serum phosphate, delaying progression of vascular calcification and improving renal function. 相似文献
33.
患者女,32岁.因白带增多半年,接触性出血3个月入院.妇科检查:阴道通畅;宫颈前唇隆起,前穹隆、左右穹隆消失,肿物向直肠方向突起;子宫界限不清,双附件增大.实验室检查:肿瘤相关抗原(CA125)73 U/mL. 相似文献
34.
探讨钙化的血管平滑肌细胞肾上腺髓质素生成和肾上腺髓质素受体系统一降钙素受体样受体和受体活性修饰蛋白基因表达的改变及其病理意义。采用β-甘油磷酸盐诱导培养的大鼠血管平滑肌细胞钙化;放射免疫法测定血管平滑肌细胞分泌的肾上腺髓质素含量;半定量逆转录聚合酶链反应测定细胞肾上腺髓质素、降钙素受体样受体和受体活性修饰蛋白的mRNA水平;原子吸收分光光度计测定细胞钙含量;碱性磷酸酶试剂盒测定血管平滑肌细胞碱性磷酸酶活性;β液体闪烁计数仪测定45Ca2+放射活性。结果发现,与非钙化血管平滑肌细胞比较,钙化血管平滑肌细胞内钙含量、45Ca2+摄入及碱性磷酸酶活性分别增加118%、174%和7倍(P<0.01);钙化细胞肾上腺髓质素分泌量增高99%(P<0.01),肾上腺髓质素、降钙素受体样受体、受体活性修饰蛋白2和3的mRNA水平分别增加78%、93.7%、91.8%和109.5%(P均<0.01)。肾上腺髓质素与降钙素受体样受体、受体活性修饰蛋白2和3的mRNA水平呈正相关,其相关系数分别为0.83、0.92和0.93(P均<0.01)。结果提示,血管平滑肌细胞肾上腺髓质素 旁/自分泌功能改变可能参与血管钙化的调节过程。 相似文献
35.
Jing Liu Shengping Zhong Hualin Lan Xu Meng Haibo Zhang Yubo Fan Yuxing Wang Chunren Wang Zhaoxu Wang 《Biomaterials》2014
The calcification initiation and progression of bioprosthetic heart valve were investigated in a rat model by enhanced micro-computed tomography, together with histologic study and scanning electron microscope analysis. The implantation data at early stage showed apparent dendritic patterns in the radiographic images for the glutaraldehyde-treated bovine pericardium and this dendritic pattern was verified to be associated with the vessel distribution in the tissue. Histologic study and scanning electron microscope analysis both indicated that the calcium deposits in the pericardium vessels regions were more grievous than those scattered in the collagen fibers in the first two weeks after implantation. Subsequently, calcification spreaded and the entire sample was severely calcified in 60 days. 相似文献
36.
目的:研究淫羊藿苷(Icariin)对大鼠血管平滑肌细胞(VSMCs)钙化的抑制作用。方法:组织贴壁法培养大鼠胸主动脉VSMCs,取5-8代细胞分为对照组、钙化模型组和淫羊藿苷干预A、B、C组。对照组用DMEM培养基培养;钙化模型组用含10mmol/Lβ-甘油磷酸盐(β-GP)的DMEM培养基培养;干预A、B、C组均以钙化模型组为基础分别与10-6 mol/L、10-5 mol/L和10-4 mol/L Icariin的DMEM培养基共培养,茜素红-S染色法鉴定各组细胞钙化情况,硝基苯酚法测定各组细胞碱性磷酸酶(ALP)活性,RT-PCR检测各组细胞内骨保护素(OPG)和核因子κB(NF-κB)受体活化因子配体(RANKL)的mRNA水平,用Western blotting检测各组细胞OPG和RANKL的蛋白表达。结果:与对照组比较,钙化模型组VSMCs发生细胞钙化,并形成红色结节,ALP活性显著升高(P0.01),OPG、RANKL mRNA和蛋白表达均增加(P0.01);与钙化模型组比较,干预A、B、C组细胞钙化减少,ALP活性减低(P0.01),OPG、RANKL mRNA和蛋白表达均下调(P0.01),尤以干预B组效果最显著。结论:淫羊藿苷可能通过降低ALP活性及OPG、RANKL表达来抑制动脉钙化。 相似文献
37.
年龄与性别在冠状动脉钙化程度和冠心病诊断价值中的影响 总被引:38,自引:3,他引:38
目的:探讨年龄和性别在电子束CT(EBCT)测定冠状动脉钙化(CAC)程度及其对冠心病诊断价值的影响。方法:2642例患行EBCT检测CAC并计算每例的总积分,分析年龄和性别与CAC检测阳性率及CAC总积分的关系;其中同期经选择性冠状动脉造影检查的患432例,评价CAC对冠心病的诊断价值及年龄和性别的影响。结果:(1)2642例患总的检测阳性率为69.3%,其中男性和女性分别为73.1%和60.4%,阳性率男性显高于女性(P<0.001)。两性的阳性率都随年龄增大而增高;70岁以下各年龄组男性均明显高于女性,但60岁以后两性差距逐渐缩小,70岁以上各年龄组两性间比较,差异无显性;(2)男女两性钙化积分的自然对数转换值的均数都年龄增大而增高,性别差异与年龄阳性率相似;(3)CAC诊断冠心病的敏感性、CAC诊断冠心病的敏感性在≥60岁男性组最高,<60岁女性组最低;而诊断特异性则与之相反。结论:冠状动脉钙化程度随年龄增大而加重,男性一般重于同龄女性,但60岁以后女性钙化程度迅速增加并逐渐接近同龄男性;年龄和性别对冠状动脉钙化诊断冠心病的价值有很大影响。 相似文献
38.
冠状动脉粥样硬化性心脏病单支病变和多支病变的血管壁结构的对比研究 总被引:1,自引:0,他引:1
目的:冠状动脉造影显示的单支病变和多支病变,只是粗略地反映了血管腔狭窄的程度和范围,无法反映血管壁病变的具体情况。本试验利用血管内超声检测左主干来阐述上述两类患者冠状动脉粥样硬化病变的特点。方法:129例冠心病患者被入选,分为单支病变组49例,多支病变组80例。所有患者在进行左冠状动脉系统的介入检查和治疗时,给予左主干的血管内超声检查,然后在每间隔1 mm的超声断面上测量血管外腔面积、内腔面积、斑块面积以及钙化角度,再将所有检测断面的相应数值相加,从而得到整个左主干的外腔容积、内腔容积、斑块体积和总的钙化负荷,最后比较在最小内腔面积的血管断面上以及整个左主干,各检测数据在两组间的差别。结果:左主干血管内、外腔和粥样斑块的定量血管内超声方面:无论在最小内腔面积(MLA)部位还是在整个左主干(除斑块面积、血管外腔外),单支病变组的血管外腔面积、血管内腔面积均显著大于多支病变组,斑块负荷均显著低于多支病变组,均有显著性差异(P<0.05~0.001)。在MLA横断面上,单支病变组的斑块偏心指数显著高于多支病变组(0.46±0.18对0.33±0.22,P=0.001),即前者斑块的偏心程度显著低于后者。在粥样斑块的钙化方面:单支病变组钙化阳性率显著低于多支病变组,均有极显著性差异(P<0.001)。其次,对钙化角度的定量分析显示,单支病变组患者MLA部位的钙化度数、左主干总钙化度数、最大钙化度数以及平均钙化度数均显著低于多支病变组,均有极显著性差异(P<0.001)。结论:冠状动脉造影显示的单支和多支病变存在粥样硬化斑块病理结构的显著差异,表现为多支病变的患者斑块负荷更重,钙化几率和钙化程度更高。 相似文献
39.
目的:探讨老年性钙化性心脏瓣膜病的临床特点及其与冠心病的关系。方法:回顾分析1998年至2004年间652例>60岁住院老年人的超声心动图及临床资料。结果:钙化性瓣膜病的发生部位以主动脉瓣最多见;经过临床诊断确诊为冠心病的有425例,以ACS为主,其次是陈旧性心肌梗死,稳定型心绞痛。钙化性心脏瓣膜病与血糖、血压、血超敏C反应蛋白(CRP)、血脂异常、冠心病高有关,钙化组的总胆固醇(TC)、甘油三酯(TG)、低密度脂蛋白(LDL)均明显高于非钙化组(P<0.001)。在钙化组,冠心病的患病率明显高于非钙化组(P<0.01)。结论:钙化性心脏瓣膜病与冠心病、高血压病、血脂异常、血糖、血超敏C反应蛋白关系密切,超声心动图可作为常规检查手段。CRP可以作为预测心脏钙化性瓣膜病的指标。 相似文献
40.
Martin Haensig Thomas Kuntze David Lopez Gonzalez Harald Lapp Philipp Lauten Tamer Owais 《Interactive Cardiovascular and Thoracic Surgery》2022,34(2):167
Open in a separate windowOBJECTIVESThis study sought to report the calcification pattern of the mitral valve annulus and its implications for procedural and safety outcomes in transcatheter aortic valve implantation.METHODSBetween November 2018 and September 2019, a total of 305 patients had transcatheter aortic valve implants at our institution. The extent of calcification of the mitral valve annulus was analysed, and the impact on safety outcomes was evaluated.RESULTSThe prevalence of mitral annular calcification (MAC) was 43%. Calcification of the mitral valve annulus was either less than or at least one-third of the posterior annulus (34% and 32%), the whole posterior annulus (28%) or the extension to the attachment of the anterior leaflets (7%). Severe circumferential MAC revealed moderate paravalvular leaks in 5/8 (63%) patients and was associated with right branch bundle block [odds ratio (OR) 2.01 (0.39–3.06); P = 0.098] and low cardiac output [OR 3.12 (1.39–7.04); P = 0.033]. Subannular calcification at the anterolateral trigonum represented a risk factor for left ventricular outflow tract injury [OR 3.54 (1.38–8.27); P = 0.001] in balloon-expandable valves, associated with relevant rhythm disorders [OR 2.26 (1.17–5.65); P = 0.014] and female gender (7/8, 88%). The 30-day all-cause mortality in circumferential MAC reaching into the anterior annulus (grade IV) compared to patients with less MAC (grade I–III) was 13% vs 2% with a mean valve size of 24.6 vs 25.7 mm.CONCLUSIONSExtensive MAC was associated with moderate paravalvular leaks, with implications for the prosthesis size and survival in transcatheter aortic valve implants. In severe MAC, we recommend implanting oversized self-expandable prostheses, the goal being to reduce the risk of right branch bundle block and paravalvular leaks.Subj collection122, 125 相似文献