Serum uric acid in patients with ST-segment elevation myocardial infarction: An innocent bystander or leading actor?

Elevated serum uric acid (SUA) levels have been associated with several cardiovascular risk factors and the progression of coronary artery disease. In the setting of acute myocardial infarction, increasing evidence suggests that high SUA levels could be related to adverse outcomes. Interestingly elevated SUA levels have been linked to endothelial dysfunction, inflammation and oxidative stress. The aim of this review is to discuss the potential negative effects of SUA in patients with ST-segment elevation myocardial infarction undergoing primary percutaneous coronary intervention, analyzing the possible underlying pathophysiological mechanisms.     

基于肿瘤浸润深度及大小的TTS 评分系统对可切除胃癌患者预后判断的价值

目的:探讨基于肿瘤浸润深度及大小的TTS评分系统对可切除胃癌患者预后判断的价值。方法:选择行根治性切除的234例胃癌患者为研究对象。根据肿瘤浸润深度（T分期）和肿瘤大小构建TTS评分系统，分为TTS 0级、1级、2级，代表肿瘤侵袭性逐渐升高。通过Cox多因素模型分析TTS评分系统作为预后判断工具的可行性。结果:T1-T4期患者肿瘤的平均大小分别为(3.3±2.7)cm、(4.1±3.1)cm、(6.6±3.1)cm、(9.4±4.9)cm。单因素分析显示，肿瘤浸润深度与肿瘤大小、淋巴结转移、TNM分期、淋巴浸润和血管浸润显著相关(P＜0.01)。ROC曲线显示，45 mm为肿瘤大小的最佳界值，可有效区分患者是否存在淋巴结转移，曲线下面积(area under curve,AUC)为0.762。综合肿瘤大小的临界值和肿瘤浸润深度，构建TTS评分系统,TTS 0级、TTS 1级和TTS 2级的患者5年生存率分别为95.6%、83.3%和70.2%，两两比较后发现，不同TTS状态患者的生存率之间均存在显著差异(P＜0.01)。Cox多因素分析发现，TTS评分是影响患者预后的独立性危险因素（P＜0.05）。结论:本研究根据肿瘤浸润深度和大小构建了TTS评分系统，并证明了TTS评分与胃癌患者的预后密切相关。     

Sample size re-estimation for clinical trials with longitudinal negative binomial counts including time trends

In some diseases, such as multiple sclerosis, lesion counts obtained from magnetic resonance imaging (MRI) are used as markers of disease progression. This leads to longitudinal, and typically overdispersed, count data outcomes in clinical trials. Models for such data invariably include a number of nuisance parameters, which can be difficult to specify at the planning stage, leading to considerable uncertainty in sample size specification. Consequently, blinded sample size re-estimation procedures are used, allowing for an adjustment of the sample size within an ongoing trial by estimating relevant nuisance parameters at an interim point, without compromising trial integrity. To date, the methods available for re-estimation have required an assumption that the mean count is time-constant within patients. We propose a new modeling approach that maintains the advantages of established procedures but allows for general underlying and treatment-specific time trends in the mean response. A simulation study is conducted to assess the effectiveness of blinded sample size re-estimation methods over fixed designs. Sample sizes attained through blinded sample size re-estimation procedures are shown to maintain the desired study power without inflating the Type I error rate and the procedure is demonstrated on MRI data from a recent study in multiple sclerosis.     

胃癌前病变信号通路及相关中医药治疗的研究进展

中国肿瘤患者中，胃癌的发病率及病死率均较高。胃癌前病变（PLGC）是胃癌发展的关键阶段，及时诊断、干预PLGC，可降低胃癌发生发展风险。PLGC的治疗，西医目前以抗幽门螺杆菌（Hp）、补充维生素、叶酸、非甾体类药物为主，同时密切随访，其疗效尚有争议。中医药治疗PLGC独具特色，且已有许多研究证实其疗效可靠，但具体机制尚未完全明确，故综述PLGC的常见信号通路及中医药治疗机制的研究进展。