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161.
162.
Katarzyna Romejko Aleksandra Rymarz Katarzyna Szamotulska Zbigniew Bartoszewicz Stanisaw Niemczyk 《Nutrients》2022,14(14)
Background: Osteoprotegerin (OPG) is a molecule which belongs to the tumor necrosis factor receptor superfamily. OPG concentration is elevated in patients with left ventricle hypertrophy, heart failure and acute myocardial infarction. OPG concentrations rise in chronic kidney disease (CKD). The aim of this study was to investigate the association between OPG concentrations and cardiovascular complications, such as left ventricle hypertrophy, systolic and diastolic dysfunction of left ventricle and dysfunction of right ventricle in chronic kidney disease patients not treated with dialysis. The relation between OPG and the amount of pericardial fluid was also examined. Methods: One hundred and one men with CKD stage 3–5 not treated with dialysis were included in the study. Overhydration, body fat mass and lean body mass were measured using bioimpedance spectroscopy (BIS). Echocardiography was performed to evaluate the amount of pericardial fluid and to measure the thickness of the interventricular septum (IVS), systolic and diastolic function of left ventricle, as well as systolic function of right ventricle. Results: We observed a significant positive association between OPG and the thickness of the interventricular septum, the size of the left atrium (LA) and the presence of pericardial fluid. A negative relationship was observed between OPG and ejection fraction (EF). Conclusions: Our results suggest that OPG can be an independent marker of left ventricular hypertrophy, systolic and diastolic dysfunction of left ventricle and the presence of pericardial fluid in chronic kidney disease patients. 相似文献
163.
目的 应用超声技术对比研究血管紧张素Ⅱ( AngⅡ)诱导的TR3敲除C57BL/6小鼠(TR3-/-小鼠)和野生型C57BL/6小鼠(TR3+/+小鼠)心肌肥大后心肌厚度的变化,初步探讨TR3是否参与心肌肥大的过程.方法 将26只TR3 -/-小鼠及33只TR3+/+小鼠根据是否给予AngⅡ按随机原则分为TR3+/+ + AngⅡ组(27只)、TR3+/+ +PBS组(6只)、TR3-/- +AngⅡ组(20只)、TR3-/- +PBS组(6只)共4组.将注有AngⅡ或PBS的皮下渗透微泵埋入小鼠皮下释放4周,构建小鼠高血压模型,分别于埋泵前2d、埋泵后第1、2、3、4周共5次超声测量小鼠舒张末期室间隔厚度(IVSd)及右室后壁厚度(LVPWd).之后处死小鼠,取心肌组织进行HE染色、Western Blotting检测,对比各组差异.结果 ①超声心动图:TR3+/+ +组及TR3-/-组小鼠在埋泵前,IVSd及LVPWd未见明显差异(P>0.05);埋泵后第1~2周,TR3-/- + AngⅡ组和TR3+/+ + AngⅡ组小鼠IVSd及LVPWd达到峰值;埋泵后第2周,TR3+/+ +AngⅡ组小鼠IVSd及LVPWd明显高于TR3+/+ +PBS组(P<0.05);TR3-/- +AngⅡ组小鼠IVSd及LVPWd略高于TR3-/- +PBS组(P <0.05);TR3+/+ + AngⅡ组小鼠IVSd及LVPWd较TR3-/- +AngⅡ组小鼠明显增高(P<0.05);给药至第4周,IVSd及LVPWd与第2周比较差异无统计学意义(P>0.05).②心肌组织HE染色:注射AngⅡ的TR3+/+小鼠心肌细胞出现了明显增大,而TR3-/-小鼠心肌细胞增大不明显.③Western blotting:注射AngⅡ的TR3+/+小鼠心肌细胞TR3表达明显增高(P<0.05).结论 TR3参与了AgⅡ诱导的小鼠心肌肥大过程,TR3是小鼠受到AngⅡ刺激后引起心肌肥大的关键因素. 相似文献
164.
腹膜透析患者低白蛋白血症对其左心室结构和功能的影响 总被引:2,自引:0,他引:2
目的:探讨腹膜透析(PD)患诸因素对左心室结构和功能的影响。方法:20例PD患,所有患进行超声心动图与心功能检测,并根据Devereux公式计算左心室心肌重量指数(LVMI)。将患的年龄、PD时间、Kt/v、Hb、TG、Tch、血浆白蛋白(SA)、nPCR、CBP、PTH、PD超滤量与左心室射血分数(EF)、LVMI和左心室舒张早期和晚期最大血流速度比(E/A)进行逐步回归分析。患的收缩压与LVMI,CRP、nPCR分别与SA作直线相关分析。结果:LVH发生率为55%,E/A<1占95%,逐步回归分析显示:SA与LVMI呈显负相关(r^2=0.3619,P=0.005),年龄与E/A呈负相关(r^2=0.58,P=0.0245)。直线相关分析示收缩压与LVMI呈正相关。CRP与SA呈显负相关,nPCR与SA呈正相关。SA<30g/L,LVH发生率为73%,较高于SA≥30g/L,左心室舒张功能障碍前较后为多。结论:PD患LVH发生率高,低白蛋白血症是值得关注的重要危险因素之一。 相似文献
165.
国产内支架治疗前列腺增生 总被引:4,自引:0,他引:4
目的 探讨国产前列腺内支架治疗前列腺增生引起排尿困难的临床疗效。方法 3 2例前列腺增生引起排尿困难的患者 ,置入 3 5枚前列腺内支架。支架均为国产镍钛记忆合金编织而成。结果 3 2例均一次治疗成功 ,2 8例置入支架后立即自行排尿 ,3例因前列腺增生过大 ,前列腺尿道部过长 ,置入 1个支架 ,排尿仍有困难 ,再次置入第 2个支架后 ,立即自行排尿 ,1例伴有糖尿病的患者 ,置入支架 1周后排尿困难未改善 ,而进行外科手术治疗。 2 8例生活质量积分 0~ 3分 ,19例术后随访 6~ 18个月 ,国际前列腺症状评分 (I PSS)术前 2 7.5 9± 4.11,术后 6.93± 3 .76(P <0 .0 0 1) ,最大尿流率术前 (1.79± 3 .89)ml/s,术后 (14 .2 5± 3 .65 )ml/s(P <0 .0 0 1)。结论 前列腺支架治疗前列腺增生引起的排尿困难是可靠的。 相似文献
166.
目的:探讨高糖、胰岛素对肾小球系膜细胞中细胞周期蛋白依赖性激酶抑制剂P21表达的影响及其与系膜细胞肥大的关系。方法:将培养的大鼠1097系膜细胞株分为8组:正常对照组,高糖组,甘露醇组,不同浓度胰岛素组,高糖加不同浓度胰岛素组。用RT-PCR法检测各组系膜细胞P21mRNA表达。流式细胞仪定量检测各组系膜细胞前向角度散射光(FSC)大小。结果:正常对照组系膜细胞中P21mRNA有一定表达。高糖组P21mRNA表达明显增加为正常对照组的3.89倍(P<0.01);FSC为正常对照组的1.42倍(P<0.01)。不同浓度胰岛素组系膜细胞P21mRNA表达及FSC大小随胰岛素浓度增加而增加,但无统计学意义(P>0.05)。结论:(1)P21mRNA在正常肾小球系膜细胞有一定表达。(2)高糖刺激可使系膜细胞P21mRNA表达上调,且与渗透压无明显关系。(3)P21mRNA表达上调可导致系膜细胞肥大,在糖尿病肾病发病机制中起重要作用。 相似文献
167.
Weijun Li Zhenhong Zhu Kai He Xiaoyu Ma Robert J. Pignolo Gary C. Sieck Jinghua Hu Haitao Wang 《Proceedings of the National Academy of Sciences of the United States of America》2022,119(24)
Skeletal muscle atrophy is commonly associated with aging, immobilization, muscle unloading, and congenital myopathies. Generation of mature muscle cells from skeletal muscle satellite cells (SCs) is pivotal in repairing muscle tissue. Exercise therapy promotes muscle hypertrophy and strength. Primary cilium is implicated as the mechanical sensor in some mammalian cells, but its role in skeletal muscle cells remains vague. To determine mechanical sensors for exercise-induced muscle hypertrophy, we established three SC-specific cilium dysfunctional mouse models—Myogenic factor 5 (Myf5)-Arf-like Protein 3 (Arl3)−/−, Paired box protein Pax-7 (Pax7)-Intraflagellar transport protein 88 homolog (Ift88)−/−, and Pax7-Arl3−/−—by specifically deleting a ciliary protein ARL3 in MYF5-expressing SCs, or IFT88 in PAX7-expressing SCs, or ARL3 in PAX7-expressing SCs, respectively. We show that the Myf5-Arl3−/− mice develop grossly the same as WT mice. Intriguingly, mechanical stimulation-induced muscle hypertrophy or myoblast differentiation is abrogated in Myf5-Arl3−/− and Pax7-Arl3−/− mice or primary isolated Myf5-Arl3−/− and Pax7-Ift88−/− myoblasts, likely due to defective cilia-mediated Hedgehog (Hh) signaling. Collectively, we demonstrate SC cilia serve as mechanical sensors and promote exercise-induced muscle hypertrophy via Hh signaling pathway.Exercise is considered as the primary intervention to improve muscle strength and to counteract muscle atrophy. While physical exercise training is considered a suitable intervention to improve muscle strength and endurance in healthy individuals, some people are resistant to the beneficial effects of exercise (1–3). It has been debated whether exercise is beneficial or harmful for patients with myopathic disorders (4) and type 2 diabetes (5). This so-called “exercise resistance” is considered congenital, and one recently identified causative factor involved in exercise resistance is hepatokine selenoprotein P (2, 6).Primary cilia have a mechanosensory function in bone cells (7), renal cells (8), and airway smooth muscle cells exert a role in sensing oscillatory fluid flow and transducing extracellular mechano-chemical signals into intracellular biochemical responses (9). Intriguingly, low muscle tone is a clinical feature often present in congenital ciliopathies with unclear underlying mechanisms (10). Arf-like Protein 3 (ARL3) is a highly conserved ciliary protein across ciliated organisms. ARL3, a regulator of intraflagellar transport in primary cilia, has been reported involving with various ciliary signaling functions (11, 12) and maintaining cell division polarity (13). Arl3 mutations cause Joubert syndrome (14, 15). Arl3−/− knockout does not affect cilia structure but compromises ciliary function (16).Cells utilize primary cilia to convert environmental cues, mechanical or chemical, into various cellular signaling essential for development (17–21). During skeletal muscle development, Hedgehog (Hh) signaling helps to initiate the myogenic program (22). In myoblast cells, Fu et al. (23) showed that primary cilia are assembled during the initial stages of myogenic differentiation but disappear as cells progress through myogenesis. The ablation of primary cilia suppresses Hh signaling and myogenic differentiation while enhancing proliferation. However, there are still significant gaps in our understanding of how exercise and mechanical signals activate the Hh signaling pathway. In the present study, we hypothesize that primary cilia in satellite cells (SCs) transduce mechanical stimulation through activation of Hh signaling and promote muscle hypertrophy induced by exercise.Hypertrophy of skeletal muscle is a complex biological process that involves multiple cell types, including SCs, fibro-adipogenic precursors, endothelial cells, fibroblasts, pericytes, and immune cells. Removing cilia from fibro-adipogenic precursors can reduce intramuscular adipogenesis and increase myofibril size during muscle healing (24). SCs play an essential role in muscle hypertrophy and exercise adaptation (25, 26), especially in young mice (27). Mechanical signals can interrupt SC suppression in a skeletal muscle loss model induced by ovariectomy. Diminished SC number and elevated adipogenic gene expression in muscle caused by ovariectomy are averted by mechanical stimulation (28). Experiments in vitro indicate that mechanical stimulation enhances the fusion of SCs (29). SCs are a heterogeneous population of stem cells and committed progenitors (30). Paired box protein Pax-7 (Pax7) is a traditional marker of SCs and acts at different levels in a nonhierarchical regulatory network controlling SC-mediated muscle hypertrophy (31). A major target gene of Pax7 is Myogenic factor 5 (Myf5), and loss of Pax7 significantly decreases Myf5 expression in myoblasts (32). However, Myf5 is present in Pax3/Pax7 double mutants, indicating Myf5 activation occurs independently of Pax3/Pax7 (33). Furthermore, 10% of Pax7-expressing satellite cells have never expressed Myf5 (30). Parise et al. (34) observed an approximately sixfold increase in the number of Myf5-expressing cells by 48 h following exercise, which remained elevated until at least 96 h after exercise. We established three mouse models of Myf5-Arl3−/−, Pax7-Intraflagellar transport protein 88 homolog (Ift88−/−), and Pax7-Arl3−/− to investigate the SC during mechanical stimulation and exercise. In the present study, we provide exciting evidence that SC cilia act as the key mechanical sensor for exercise-induced hypertrophy. 相似文献
168.
目的 探讨儿童肥大腺样体切除术对分泌性中耳炎预后的影响.方法 对2012年4月至2013年4月来我院就诊的120例伴有腺样体肥大的分泌性中耳炎患儿进行研究,随机分为观察组60例(药物治疗+鼻内镜下吸切器腺样体切除术)和对照组60例(单纯药物治疗),观察治疗30天及12个月后两组的有效率,分别进行治疗前后纯音测听分析,探讨肥大腺样体切除术对分泌性中耳炎预后的影响.结果 治疗后30 d,两组有效率相比差异无统计学意义(P>0.05);而治疗后12个月,观察组有效率显著高于对照组,差异具有统计学意义(P<0.05).纯音测听结果显示,治疗后30 d,观察组与对照组纯音测听结果相比差异无统计学意义(P>0.05),治疗后12个月,观察组听力提高较对照组显著,差异具有统计学意义(P<0.05).结论 腺样体切除术对治疗分泌性中耳炎具有重要的作用,且治疗过程安全,复发率低,治愈的效率高,预后良好,在临床实践过程中,值得推广这种治疗方法. 相似文献
169.
目的:探讨鼻内镜下腺样体切除术的可行性和优点。方法:在鼻内镜下对54例儿童肥大腺样体切除,治疗由腺样体肥大引起的临床症状。结果:术后鼻咽部结构显示良好,无残体存留,无咽鼓管损伤等并发症。结论:鼻内镜下腺样体肥大切除手术能在直视下进行,病变切除准确、彻底,手术疗效明显。 相似文献
170.
目的探讨老年高血压患者动态血压(ABPM)参数及体重指数(BMI)与左心室肥厚(LVH)之间的关系。方法采用袖带式24小时动态血压仪监测293例老年高血压患者的ABPM,彩色超声测量左心室参数,LVH者为研究组(131例),非LVH组(162例)为对照组,研究LVH与ABPM监测参数:平均收缩压(SBP)、平均舒张压(DBP)、脉压差(PP)、心率(HR)、BMI的关系。结果LVH与动态血压SBP、DBP、PP、HR水平成正相关(P<0.05),BMI的变化在上述两组间无统计学意义(P>0.05)。结论老年高血压LVH与动态血压SBP、DBP、PP、HR水平密切相关,他们可能都是影响老年高血压患者病情进展及预后的重要因素。 相似文献