Premature Ticagrelor Discontinuation in Secondary Prevention of Atherosclerotic CVD: JACC Review Topic of the Week

Ticagrelor is a cornerstone of modern antithrombotic therapy alongside aspirin in patients with acute coronary syndrome and after percutaneous coronary intervention. Adverse effects such as bleeding and dyspnea have been associated with premature ticagrelor discontinuation, which may limit any potential advantage of ticagrelor over clopidogrel. The randomized trials of ticagrelor captured adverse events, offering the opportunity to more precisely quantify these effects across studies. Therefore, a meta-analysis of 4 randomized clinical trials of ticagrelor conducted between January 2007 and June 2017 was performed to quantify the incidence and causes of premature ticagrelor discontinuation. Among 66,870 patients followed for a median 18 months, premature ticagrelor discontinuation was seen in 25%; bleeding was the most common cause of discontinuation followed by dyspnea. Versus the comparators, the relative risk of dyspnea-related discontinuation during follow-up was 6.4-fold higher, the relative risk of bleeding was 3.2-fold higher, and the relative risk of discontinuation due to any adverse event was 59% higher for patients receiving ticagrelor. Understanding these potential barriers to adherence to ticagrelor is crucial for informed patient-physician decision making and can inform future efforts to improve ticagrelor adherence. This review discusses the incidence, causes, and biological mechanisms of ticagrelor-related adverse effects and offers strategies to improve adherence to ticagrelor.     

Effect of regular swimming exercise to duration-intensity on neurocognitive function in cerebral infarction rat model

Objective: This study investigated the effect of regular swimming exercise according to the duration-intensity on neurocognitive function in a cerebral infarction rat model.

Methods: Forty male Sprague–Dawley 10-week-old rats, weighing 300 ± 50 g, were subjected to photothrombotic cerebral infarction. The remaining 36 rats were randomly divided into four groups (n = 9 per group: non-exercise (group A); swimming exercise of short duration-intensity (5 min/day, group B); swimming exercise of moderate duration-intensity (10 min/day, group C); and swimming exercise of long duration-intensity (20 min/day, group D). Exercise was performed five times a week for 4 weeks, beginning the day after cerebral infarction. Neurocognitive function was evaluated with the Morris water maze test. Immunohistochemistry and western blot analysis examined brain-derived neurotrophic factor (BDNF) and vascular endothelial growth factor (VEGF) at 4 weeks postinfarction.

Results: At 4 weeks postinfarction, escape latency was found to be shorter in group C than in any of groups A, B, or D. Immunohistochemistry revealed the most significant immunoreactivity for BDNF and VEGF in group C. Western blot analysis demonstrated that BDNF and VEGF proteins were markedly expressed in group C.

Conclusions: Regular swimming exercise of moderate duration-intensity may be the most effective exercise protocol for the recovery of neurocognitive function in cerebral infarction rat model.     

Therapeutic effect of mesenchymal stem cell on Hashimoto’s thyroiditis in a rat model by modulating Th17/Treg cell balance

Abstract

The autoimmune condition Hashimoto’s thyroiditis (HT) is a disease wherein lymphocytes mediate the autoimmune damage and destruction of the thyroid gland. There are currently no effective means of treating HT, with the primary strategies of thyroid hormone therapy, surgery, or immunomodulatory therapy being associated with serious risks and side effects. There is thus a clear and urgent need to identify novel treatments for HT. In this study, we utilize female SD rats induced HT to evaluated the ability of transplanted MSCs to regulate Th17/Treg interactions in a rat Hashimoto’s thyroiditis (HT) model system. The results showed that Rats in the HT model group exhibited increased thyroid autoantibody levels consistent with successful model development, whereas these levels were lower in rats treated with MSCs. There were also fewer thyroid lesions and less lymphoid infiltration of the thyroid in MSC-treated rats relative to HT model rats, as well as fewer Th17 cells and more Treg cells – an observation consistent with the cytokine analyses. All of these showed that MSCs can regulate Th17/Treg interactions in a rat Hashimoto’s thyroiditis (HT) model system. It suggested that transplanted MSCs could be a potential immunotherapy strategy for the treatment of Hashimoto’s thyroiditis.     

Cyclin D1启动子在养精胶囊促进小鼠精原干细胞增殖中的作用※

目的 研究养精胶囊促进小鼠精原干细胞（SSCs）增殖的分子机制。方法 将不同浓度的养精胶囊提取物加入SSCs中培养48 h，CCK-8检测细胞的增殖活性，流式细胞仪检测细胞周期，荧光素酶报告基因检测Cyclin D1启动子的活性，qRT-PCR以及免疫荧光检测Cyclin D1的表达。之后进行阻断实验，在加入养精胶囊前预先加入siRNA-Cyclin D1，同样的方法检测细胞的增殖活性、细胞周期、Cyclin D1启动子的活性以及Cyclin D1的表达情况。结果 低、中、高浓度的养精胶囊可以促进SSCs的增殖，提高S期细胞的比例，增强Cyclin D1启动子的活性，促进Cyclin D1的表达。阻断Cyclin D1后，SSCs的增殖活性降低，S期细胞比例减少，Cyclin D1启动子的活性降低，Cyclin D1的表达减少。结论 养精胶囊通过增强Cyclin D1启动子的活性提高Cyclin D1的转录和翻译水平，进而促进SSCs增殖。     

进展型脑梗死患者miRNA的表达水平及临床意义

目的探讨进展型脑梗死患者微小RNA(miRNA)的表达水平及临床意义。方法回顾性分析2016年7月至2018年7月期间我院收治的138例脑梗死患者病例资料。根据斯堪的那维亚卒中量表(SSS)将其分为对照组(稳定型脑梗死,82例)和观察组(进展型脑梗死,56例)。观察组患者按照高级中枢损伤严重程度评定标准(MESSS)评分为轻度进展(30例)、中度进展(17例)、重度进展(9例)三个亚组。对观察组出院两个月后进行预后随访,并将其分为预后不良组及预后良好组。分析进展型脑梗死患者miRNA的表达水平及临床意义。结果进展型脑梗死患者的miRNA-21、miRNA-223水平均显著高于稳定型脑梗死患者(P 0. 05); miRNA-21、miRNA-223的高表达均是进展型脑梗死的危险因素(P 0. 05),且进展型脑梗死的严重程度与血清miRNA-21、miRNA-223的表达水平均呈正相关(r=0. 834,P=0. 008;r=0. 896,P=0. 001)。预后不良组患者血清miRNA-21、miRNA-223表达水平显著高于预后良好组(P 0. 05);血清miRNA-21、miRNA-223表达水平预测进展型脑梗死预后的AUC面积分别为0. 805、0. 834,并分别得出截断值4. 45 (敏感度77. 14%,特异性82. 28%)、7. 06(敏感度82. 86%,特异性73. 42%)。结论进展型脑梗死患者miRNA-21、miRNA-223呈高表达,且其表达水平与脑梗死严重程度呈正相关,同时对预测进展型脑梗死预后均具有较高的敏感度和特异度,有可能成为一种早期诊断和预测进展型脑梗死生物标志物。     

Sirt5 is dispensable for BrafV600E‐mediated cutaneous melanoma development and growth in vivo

Sirt5 is known to functionally regulate mitochondrial proteins by altering posttranslational modifications, including lysine desuccinylation. While roles for Sirt5 as either a tumor promoter or suppressor, or in chemoresistance, have been implicated in other cancers, the function of Sirt5 in cutaneous melanoma has not been well examined. Therefore, to determine whether Sirt5 is necessary for Braf^V600E‐mediated melanoma formation and/or disease progression, we crossed a genetically engineered murine melanoma model (Tyr^CreERT2/+; Braf^{LSL‐V600E/+}; Pten^flox/flox) to Sirt5^?/? knockout animals. In addition, we tested for synergism with a selective BRAF (V600E) inhibitor in Sirt5^?/? mouse melanoma cells. Taken together, this report demonstrates that, in these models, Sirt5 is dispensable for Braf^V600E‐mediated cutaneous melanoma formation and growth in vivo, and does not improve sensitivity to a selective BRAF inhibitor.