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51.
目的:探索血清同型半胱氨酸(Hcy)、缺血修饰蛋白(IMA)及各炎性因子与非ST段抬高急性心肌梗死(NSTEMI)患者冠状动脉病变程度的相关性.方法:将符合入选标准并经临床确诊的96例NSTEMI患者作为研究组,另外选择30例健康体检者作为对照组,检测其血清Hcy、IMA及肿瘤坏死因子-α(TNF-α)、超敏C-反应蛋白(hs-CRP)、白介素-6(IL-6)水平,并分析各因子与NSTEMI患者冠状动脉病变程度的相关性.结果:NSTEMI患者Hcy、IMA及TNF-α、IL-6、hs-CRP水平与健康对照组比较均有明显增加,且差异存在统计学意义(P<0.05);NSTEMI冠状动脉双支病变组患者Hcy、IMA及TNF-α、IL-6、hs-CRP水平与单支病变组进行比较均有明显增加,而多支病变组患者上述各项指标与双支病变组进行比较均有明显增加,且各组间差异均存在统计学意义(P<0.05);Hcy、IMA及TNF-α、IL-6、hs-CRP水平与冠状动脉病变程度均呈明显正相关(P<0.05).结论:非ST段抬高急性心肌梗死患者Hcy、IMA及TNF-α、IL-6、hs-CRP水平均较健康对照组明显增加,且随患者冠状动脉病变程度增加而增加.  相似文献   
52.
AimsAlthough some evidence suggests that omega-3 polyunsaturated fatty acids (PUFAs) supplementation influences enzymes involved in forming homocysteine (Hcy) and improving hyperhomocysteinemia, these findings are still contradictory in humans. The aim of this systematic and meta-analysis study was to investigate the effects of omega-3 supplementation on Hcy using existing randomized controlled trials (RCTs).Data synthesisAvailable databases, including PubMed/MEDLINE, Web of Science, Scopus, Cochrane Library, and Embase, were searched to find relevant RCTs up to June 2021. The effect size was expressed as weighted mean difference (WMD) and 95% confidence interval (CI).ConclusionA total of 20 RCT studies with 2676 participants were included in this article. Our analyses have shown that omega-3 supplementation significantly reduced plasma Hcy levels (WMD: 1.34 μmol/L; 95% CI: 1.97 to ?0.72; P < 0.001) compared to the control group. The results of subgroup analysis showed that omega-3 supplementation during the intervention <12 weeks and with a dose ≥3 gr per day causes a more significant decrease in Hcy levels than the intervention ≥12 weeks and at a dose <3 gr. In addition, omega-3 supplements appear to have more beneficial effects in individuals with high levels of normal Hcy. This meta-analysis showed that omega-3 supplementation significantly improved Hcy. However, further studies are needed to confirm the findings.  相似文献   
53.
Summary The high risk of cardiovascular disease in patients with diabetes mellitus, particularly in those with nephropathy, is not completely explained by classical risk factors. A high plasma homocysteine concentration is an independent risk factor for cardiovascular disease but information on its association with diabetes is limited. Fasting homocysteine concentrations were measured in the plasma of 165 diabetic patients (75 with insulin-dependent [IDDM]; 90 with non-insulin-dependent diabetes [NIDDM]) and 56 non-diabetic control subjects. Other measurements included the prevalence of diabetic complications, glycaemic control, lipid and lipoprotein levels, vitamin status and renal function tests. Patients with NIDDM had higher homocysteine levels than control subjects, whereas IDDM patients did not (9.2 ± 4.5 vs 7.7 ± 2 μmol/l, p < 0.01; and 7.0 ± 3 vs 7.4 ± 2 μmol/l, NS). Univariate correlations and multiple regression analysis showed albumin excretion rate to be the parameter with the strongest independent association with homocysteine. Patients with both types of diabetes and nephropathy had higher plasma homocysteine concentrations than those without nephropathy. Increases of homocysteine in plasma were related to increases in the severity of the nephropathy. Fasting hyperhomocysteinaemia was considered as the mean of the plasma homocysteine for all control subjects (7.5 ± 2.1 μmol/l) + 2 SD (cut-off =11.7 μmol/l). Nephropathy was present in 80 % of diabetic patients with fasting hyperhomocysteinaemia. In conclusion, increases in fasting homocysteine in diabetic patients are associated with increased albumin excretion rate, especially in those with NIDDM, thus providing a potential new link between microalbuminuria, diabetic nephropathy and cardiovascular disease. [Diabetologia (1998) 41: 684–693] Received: 4 August 1997 and in final revised form: 4 February 1998  相似文献   
54.
Hyperhomocysteinaemia is strongly associated with increased relative risk of occlusive vascular disease, mainly of the carotid and coronary arteries. The aim of our study was to assess whether raised plasma homocysteine is a risk factor for thrombotic events in patients with systemic lupus erythematosus (SLE), a condition known to be associated with premature atherothrombotic complications. The study included 34 consecutive consenting SLE patients who were seen in the Rheumatology Unit of Al-Amiri hospital, one of the main teaching hospitals in Kuwait. Twenty consenting healthy subjects were included in the control group. Twenty-four patients were grouped as SLE without thrombosis and 10 had different types of thromboses. Vitamin B12, folate, anticardiolipin antibodies (IgG and IgM), activated partial thromboplastin time (APTT) and total homocysteine level were measured for both patients and controls. A raised homocysteine concentration was defined as plasma homocysteine level above 9.4 mmol/l. Hyperhomocysteinaemia was found in 21 (61.8%) SLE patients. Low levels of folate and vitamin B12 were significantly associated with high concentrations of plasma homocysteine (r = −0.35 and −0.39, respectively, P<0.01). SLE patients with elevated homocysteine concentration have a threefold increase in odds ratio of thrombotic events after adjusting for other risk factors (male sex, shortened APTT, treatment with prednisone, low folate and vitamin B12 levels). We concluded that homocysteine is an independent risk factor for thrombosis in patients with SLE and is potentially modifiable. Received: 27 December 2001 / Accepted: 14 April 2002 Correspondence and offprint requests to: Dr I. H. Al-Salem, PO Box 16434, Al-Qadeseyah 35855, Kuwait. Tel: 965 2532025; Fax: 965 2666205; E-mail: driqbalham@hotmail.com  相似文献   
55.
高同型半胱氨酸血症是引起动脉粥样硬化的一种独立危险因素。过量服用蛋氨酸会导致血清中同型半胱氨酸浓度增高、内皮功能受损、血管舒缩功能减弱。本研究使用过量服用蛋氨酸导致高同型半胱氨酸血症大鼠,与对照组比较,观察缺血下肢血管新生的情况,判断高同型半胱氨酸血症对缺血性血管新生的影响。将36只雄性Sprague-Dawley大鼠分为两组:对照组和高同型半胱氨酸血症组。对照组始终给予自来水;高同型半胱氨酸血症组则给予含有0.5%蛋氨酸的饮水。两组动物分别按上述方法给予不同饮水2周后,手术切除左侧股动、静脉,观察缺血28d内缺血区域血管新生和侧枝血管形成的情况。过量服用蛋氨酸导致的高同型半胱氨酸血症减弱了大鼠下肢慢性缺血性血管新生和侧枝血管的建立,这可能与高同型半胱氨酸血症减弱内皮源性一氧化氮生物活性有关。  相似文献   
56.

Background

Depression and high total plasma homocysteine (tHcy) are independently associated with cognitive impairment in older adults. We designed this study to determine if high tHcy is a mediator of cognitive performance in older adults with major depression.

Methods

We recruited 358 community-dwelling older adults experiencing depressive symptoms, 236 (65.9%) of who met DSM-IV-TR criteria for major depression. Assessment included the Montgomery Asberg Depression Rating Scale (MADRS), fasting tHcy and the Consortium to Establish a Registry for Alzheimer's Disease neuropsychological battery.

Results

Individuals with major depression and high tHcy had significantly worse immediate verbal and delayed visual recall. Non-depressed participants with high tHcy had lower MMSE, immediate and delayed recall scores than those with normal tHcy. The odds of cognitive inefficiency for those with high tHcy was nearly doubled for the MMSE (OR 1.9, 95%CI 1.1–3.3), immediate (OR 1.9, 95%CI 1.1–3.5) and delayed (OR 1.9, 95%CI 1.1–3.4) word recall after adjusting for age, gender, IHD and MADRS score.

Limitations

The presence of sub-syndromal depressive symptoms in our non-depressed group and exclusion of participants with established cognitive impairment may limit the generalizability of this study.

Conclusions

Elevated tHcy was associated with weaker performance in tests of immediate and delayed memory and global cognitive performance when compared to those with normal tHcy independent of the presence of major depression or the severity of depressive symptoms. Homocysteine lowering B-vitamin supplementation may offer a potential therapeutic target to try and mitigate the often-disabling impact of cognitive deficits found in this population.  相似文献   
57.
目的 探讨同型半胱氨酸(homocysteine,Hcy)与高血压患者轻度认知障碍的相关性。
方法 回顾性纳入2017年1月-2018年2月邯郸市第一医院神经内科连续收治的原发性高血
压患者,根据其血浆Hcy水平,将患者分为单纯型高血压组(Hcy<15 μm m ol/L)与H型高血压组
(Hcy≥15 μmmol/L),采用Spearman秩相关分析Hcy与MMSE和MoCA评分的相关性,并采用Logistic回归
分析高血压患者轻度认知功能障碍的影响因素。
结果 共纳入原发性高血压患者113例,其中单纯型高血压组49例,H型高血压组64例。H型高血压
组患者的MMSE和MoCA评分均低于单纯型高血压组(分别为24.94±1.83 vs 27.96±1.54和23.45±2.47
vs 27.24±1.80,均P <0.001)。相关分析显示,Hcy水平与MMSE和MoCA评分存在负相关性(分别为r =-
0.513和r =-0.500,均P<0.001)。多因素Logistic回归分析显示,高龄(OR 1.236,95%CI 1.124~1.361)、
H型高血压(OR 22.218,95%CI 8.243~59.654)是高血压患者轻度认知功能障碍的独立危险因素。
结论 Hcy水平升高是高血压患者轻度认知功能障碍发生的独立危险因素。  相似文献   
58.
目的:评价"活血散风"针刺法对H型高血压患者同型半胱氨酸、血压的影响及相关性。方法:选取H型高血压患者60例,随机分成对照组及观察组,每组各30例。对照组采用口服一类降压药,观察组在对照组的基础上加用"活血散风"针刺法,5次/周,2周为1个疗程,共治疗3个疗程。于治疗前、后分别检测患者的同型半胱氨酸及佩戴24h动态血压仪。结果:与对照组比较,治疗后,观察组24h平均收缩压、同型半胱氨酸水平显著低于对照组,差异具有统计学意义;治疗后2组24h平均舒张压组间比较,差异无统计学意义。曲线回归分析示,同型半胱氨酸与24h平均收缩压呈直线正相关(r=0.692,R2=0.479,P<0.05),而与24h舒张压呈三次曲线正相关(R2=0.479,P<0.05);同型半胱氨酸能解释24h平均收缩压变异的47.9%及24h平均舒张压变异的16.6%(R2=0.479、R2=0.166);同型半胱氨酸每增加1个单位,24h平均收缩压估计平均增加1.921个单位(b=1.921)。结论:"活血散风"针刺法能显著降低H型高血压患者同型半胱氨酸、改善24h平均收缩压水平;同型半胱氨酸对24h平均收缩压及舒张压均有影响,与24h平均收缩压的关系更密切,是血压升高的危险因素,且同型半胱氨酸与高血压易于并存,常伴随出现,增加心脑血管事件发生率。  相似文献   
59.
目的探讨血浆脂蛋白相关磷脂酶A2(Lp-PLA2)、同型半胱氨酸(Hcy)与动脉粥样硬化性心脑血管疾病的关系。方法将198例动脉粥样硬化性心脑血管疾病患者按有无其他危险因素分为合并其它危险因素的动脉粥样硬化性心脑血管疾病组(简称合并危险因素疾病组)和无其他危险因素的动脉粥样硬化性心脑血管疾病组(简称无危险因素疾病组)。另选取58名健康体检者作为正常对照组。采用双抗体夹心酶联免疫法(ELISA)测定3组血浆Lp-PLA2浓度,采用酶循环法测定Hcy浓度。结果与正常对照组相比,无危险因素疾病组和合并危险因素疾病组Lp-PLA2、Hcy浓度均明显升高(q=44.236、P=0.000,q=11.403、P=0.000;q=50.025、P=0.000,q=15.777、P=0.000);合并危险因素疾病组与无危险因素疾病组Lp-PLA2、Hcy浓度差异无统计学意义(q=2.299,P=0.083;q=2.586,P=0.069)。相关分析显示,在无危险因素疾病组和合并危险因素疾病组中,Lp-PLA2和Hcy均无相关性(r=0.069,P=0.375;r=0.053,P=0.566)。均衡其它危险因素,Lp-PLA2、Hcy浓度与冠心病独立相关(OR=1.917,P=0.005;OR=1.883,P=0.013)。无危险因素疾病组和合并危险因素疾病组Lp-PLA2、Hcy联合检测的阳性率均高于单项检测(χ2=8.124,P=0.004;χ2=3.933,P=0.045)。结论血浆Lp-PLA2、Hcy可作为动脉粥样硬化性心脑血管疾病的风险评估指标,二者联合检测对动脉粥样硬化性心脑血管疾病有一定的预测价值。  相似文献   
60.

Background and aims

Alterations to one-carbon metabolism, especially elevated plasma homocysteine (Hcy), have been suggested to be both a cause and a consequence of the metabolic syndrome (MS). A deeper understanding of the role of other one-carbon metabolites in MS, including s-adenosylmethionine (SAM), s-adenosylhomocysteine (SAH), and the methylation capacity index (SAM:SAH ratio) is required.

Methods and results

118 men and women with MS-risk factors were included in this cross-sectional study and cardiometabolic outcomes along with markers of one-carbon metabolism, including fasting plasma SAM, SAH, Hcy and vitamin B12 concentrations, were analysed. Multiple linear regression models were also used to examine the association between plasma one-carbon metabolites and cardiometabolic health features.We found that fasting plasma concentrations of Hcy, SAM and SAH were all positively correlated with markers of adiposity, including BMI (increase in BMI per 1-SD increase in one-carbon metabolite: 0.92 kg/m2 95% CI (0.28; 1.56), p = 0.005; 0.81 (0.15; 1.47), p = 0.02; 0.67 (?0.01; 1.36), p = 0.05, respectively). Hcy, but not SAM, SAH or SAM:SAH ratio was associated with BMI and body fat percentage after mutual adjustments. SAM concentrations were associated with higher fasting insulin (9.5% 95% CI (0.3; 19.5) per SD increase in SAM, p = 0.04), HOMA-IR (10.8% (0.8; 21.9), p = 0.03) and TNF-α (11.8% (5.0; 19.0), p < 0.001).

Conclusion

We found little evidence for associations between SAM:SAH ratio and cardiometabolic variables, but higher plasma concentrations of SAM, SAH and Hcy are related to an overall higher risk of metabolic dysfunctions.The studies were registered at www.clinicaltrials.gov (NCT01719913 & NCT01731366).  相似文献   
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