The Systemic Immune Inflammatory Index Predicts No-Reflow Phenomenon after Primary Percutaneous Coronary Intervention in Older Patients with STEMI

Purpose:Coronary no-reflow phenomenon(NRP),a common adverse complication in patients with ST-segment eleva-tion myocardial infarction(STEMI)treated by percutaneous coronary intervention(PCI),is associated with poor patient prognosis.In this study,the correlation between the systemic immune-inflammation index(SII)and NRP in older patients with STEMI was studied,to provide a basis for early identification of high-risk patients and improve their prognosis.Materials and methods:Between January 2017 and June 2020,578 older patients with acute STEMI admitted to the Department of Cardiology of Hebei General Hospital for direct PCI treatment were selected for this retrospective study.Patients were divided into an NRP group and normal-flow group according to whether NRP occurred during the operation.Clinical data and the examination indexes of the two groups were collected.Logistic regression was used to analyze the independent predictors of NRP,and the receiver operating characteristic curve was used to further analyze the ability of SII to predict NRP in older patients with STEMI.Results:Multivariate logistic analysis indicated that hypertension(OR=2.048,95%CI:1.252–3.352,P=0.004),lymphocyte count(OR=0.571,95%CI:0.368–0.885,P=0.012),platelet count(OR=1.009,95%CI:1.005–1.013,P<0.001),hemoglobin(OR=1.015,95%CI:1.003–1.028,P=0.018),multivessel disease(OR=2.237,95%CI:1.407–3.558,P=0.001),and SII≥1814(OR=3.799,95%CI:2.190–6.593,P<0.001)were independent predictors of NRP after primary PCI in older patients with STEMI.Receiver operating characteristic curve analysis demonstrated that SII had a high predictive value for NRP(AUC=0.738;95%CI:0.686–0.790),with the best cut-off value of 1814,a sensitivity of 52.85%and a specificity of 85.71%.Conclusion:For older patients with STEMI undergoing primary PCI,SII is a valid predictor of NRP.

Effects of intracoronary arterial injection of tirofiban on no-reflow phenomenon in patients with acute ST-segment elevation myocardial infarction underwent primary percutaneous coronary intervention

Objective: To compare the effect of intracoronary arterial injection of tirofiban and sodium nitroprusside (SNP) on no-reflow phenomenon in patients with acute ST-segment elevation myocardial infarction (STEMI) underwent primary percutaneous coro-nary intervention (PCI). Methods: A total of 68 patients with acute STEMI who had no-reflow phenomenon during PCI were chosen and randomly divided into SNP group (n = 34) and tirofiban group (n = 34). Aiming at no-reflow phenomenon during PCI, with the use of microcatheters, intracoronary arterial injection of tirofiban was given in tirofiban group, while intracoronary bolus of SNP was given in SNP group. Coronary angiography was conducted to record TIMI flow grade of the infarct-related artery after 10 minutes. Plasma brain natriuretic peptide (BNP) was monitored before and after PCI (in 24 hours). With the help of ultrasound cardiogram, left ventricular ejection fraction (LVEF), left ventricular end-diastolic dimension (LVEDD) and left ventricular end-systolic dimension (LVESD) were recorded and compared in 30 days after PCI. Results: The ratio of TIMI grade 3 blood flow in tirofiban group was significantly higher than that in SNP group (76.5% (26/34) vs. 52.9% (18/34), p = .03)BNP levels in two groups had no statistical significance before PCI (p = .16), but in 24 h after PCI, BNP levels in tirofiban group were significantly lower than those in SNP group ((439.00 ± 4.90) μmol/L vs. (632.00 ± 3.63) μmol/L, p = .02)In 30 days after PCI, LVEF, LVEDD and LVESD in tirofiban group were all superior to those in SNP group (all p < .05). Conclusions: Intracoronary arterial injection of tirofiban was superior to SNP in improving no-reflow phenomenon in STEMI patients after PCI in the emergency treatment. Tirofiban therapy can increase coronary blood flow and myocardial perfusion after the occurrence of no-reflow phenomenon during PCI in STEMI patients, and improve long-term prognosis.

Convergence Phenomenon with Fourier Series of tg(x2)and Alike

The Fourier series of the 2π-periodic functions tg(x2)and 1sin(x)and some of their relatives (first of their integrals) are investigated and illustrated with respect to their convergence. These functions are Generalized functions and the convergence is weak convergence in the sense of the convergence of continuous linear functionals defining them. The figures show that the approximations of the Fourier series possess oscillations around the function which they represent in a broad band embedding them. This is some analogue to the Gibbs phenomenon. A modification of Fourier series by expansion in powers cosn(x)for the symmetric part of functions and sin(x)cosn−1(x)for the antisymmetric part (analogous to Taylor series) is discussed and illustrated by examples. The Fourier series and their convergence behavior are illustrated also for some 2π-periodic delta-function-like sequences connected with the Poisson theorem showing non-vanishing oscillations around the singularities similar to the Gibbs phenomenon in the neighborhood of discontinuities of functions. .

Intracoronary nitroprusside in the prevention of the no-reflow phenomenon in acute myocardial infarction

Background No-reflow phenomenon during percutaneous coronary intervention （PCI） for acute myocardial infarction （AMI） is a predictive factor of continuous myocardial ischemia, ventricular remodeling and cardiac dysfunction, which is closely associated with a worse prognosis. This study aimed to evaluate intracoronary nitroprusside in the prevention of the no-reflow phenomenon in AMI.Methods Ninety-two consecutive patients with AMI, who underwent primary PCI within 12 hours of onset, were randomly assigned to 2 groups： intracoronary administration of nitroprusside （group A, n=46）, intracoronary administration of nitroglycerin （group B, n=46）. The angJographic results were observed. The real-time myocardial contrast echocardiography （RT-MCE）, including contrast score index （CSI）, wall motion score index （WMSI）, transmural contrast defect length （CDL） and serious WM abnormal length （WML） were recorded at 24 hours and 1 week post-PCI. High sensitivity C-reactive protein （Hs-CRP） was examined by immune rate nephelometry. N-terminal prohormone brain natriuretic peptide （NT-proBNP） was tested with enzyme-linked immunosorbent assay. Patients were followed up for six months. Major adverse cardiac events （MACE） were recorded. Results The incidence of final TIMI-3 flow in group A was much higher than that in Group B （P 〈0.05）, final corrected TIMI frame count （cTFC） in group A decreased significantly than that in group B （P 〈0.01）. The CSI, CDL/LV length, WMSI and WL/LV length in group A were significantly lower than that in group B （P 〈0.01）. Levels of Hs-CRP and NT-proBNP at 1 week post-PCI decreased significantly in group A than that in group B （P 〈0.01）. Patients were followed up for 6 months and the incidence of MACE in group A was significantly lower than that in group B （P〈0.05）.Conclusion Intracoronary nitroprusside can improve myocardial microcirculation, leading to the decrease of the incidence of no-reflow phenomenon and better prognosis.

Clinical significance of intra-aortic balloon pumping on no-reflow phenomenon of primary percutaneous coronary intervention for acute myocardial infarction

Background Percutaneous coronary intervention （PCI） is used as a treatment for acute myocardial infarction （AMI）, and one of its major complications is the angiographic no-reflow phenomenon （NR）. Although intra-aortic balloon pumping （IABP） is sometimes used in such patients to increase the diastolic coronary blood flow, there is little available information regarding the effects of IABP on the angiographic no-reflow phenomenon. Method Twenty-two AMI patient with NR were performed primary PCI between January 2006 and December 2009, of which 12 patients were selected for IABP therapy and the left 10 were selected as the control group by group procedure of odd and even days; We observed the vasoactive substance in both groups on the days of 1, 2, 3, 5, 7, 10 after the different interventions, which include plasma renin activity （PRA）, angiotensin Ⅱ （ANG Ⅱ）, aldosterone （ALD）, adrenaline （E）, and noradrenalin （NE）; In addition, cardiac structure and cardiac ventricle systolic function including left atrium medial diameter （LAMD）, left ventricular medial diameter （LVMD） Finally, left ventricular ejection fraction （LVEF） were evaluated after 10 days, 3 months and 6 months; statistics was taken to analysis. Results According to the time concentration curve, vasoactive substance of the IABP group decreased faster than that of the control group, and this difference had statistical significance （P 〈 0.01 ） ; In terms of LAMD, LVMD, and LVEF, echocardiography difference of the IABP and the control group in 10 days, 3 months, and 6 months also showed statistical significance （P 〈 0.05）. Conclusions IABP can significantly reduce the release of vasoactive substances of NR in patients of primary PCI for AMI; LAMD, LVMD and LVEF in 10 days, 3 months, and 6 months can be improved using this method, which is conducive to recovery of heart function.

Application of intra-aortic balloon pumping on no-reflow phenomenon in primary PCI for STEMI

Background To investigate the effect of intra-aortic balloon pumping （IABP） on no-reflow phenomenon primary percutaneous coronary intervention （PCI） for ST-Elevation Myocardial Infarction （STEMI）. Methods Clinical data of 22 acute myocardial infarction patients after PCI with angiographic no-reflow phenomenon were retrospectively analyzed between January 2006 and December 2009.12 patients underwent IABP, other 10 patients as control group. We observed difference of cardiac structure, brain natriuretic peptide （BNP） and ventricular systolic function between two group, as well as cardiac injury markers （MYO,CK-MB, cTnI） in both groups on the days of 1, 2, 3, 5, 7, 10 after the different interventions. In addition, cardiac structure and ventricular systolic function including left atrium medial diameter （LAMD）, left ventricular medial diameter （LVMD）, left ventricular ejection fraction （LVEF） was evaluated after 10 days, 3 months,6 months Finally, statistics was used to analysis the data. Results The several vasoactive substances as well as cardiac injury markers and LAMD, LVMD, LVEF of 10 days, 3 months, 6 months of IABP group were significant difference with control group significant difference （P 〉 0.0 PCI with angiographic no-reflo （P 〈 0.05）. 5）. Conclusions w phenomenon, BNP targets of IABP group compared with the control group no IABP has effects on prognosis in STEMI patients who performed which is conducive to recovery of heart function.

Feasibility of lymphocyte-to-monocyte ratio in predicting no-reflow phenomenon in ST-elevation myocardial infarction patients undergoing primary percutaneous coronary intervention

Background The no-reflow phenomenon is correlated with adverse effects on short-term and long-term outcomes of ST-elevation myocardial infarction(STEMI) in patients undergoing primary percutaneous coronary intervention(PCI). The lymphocyte-to-monocyte ratio(LMR) is a novel inflammatory marker which is associated with slow coronary flow. We aimed to investigate the predictive value of LMR for no-reflow phenomenon in patients with STEMI undergoing primary PCI. Methods A total of 1350 STEMI patients were enrolled in this study from January 2014 to January 2018. Blood samples were obtained at initial admission for analysis of LMR.The univariate and multivariate logistic regression analysis was performed to study the relationship between LMR and no-reflow phenomenon. Results All the 156 patients among the study population suffered from no-reflow phenomenon during the procedure. The LMR level was significantly lower in patients with no-reflow(1.6 ±1.0 vs. 3.25 ± 1.8, P<0.001). Multivariate logistic regression analysis showed that LMR was independently associated with no-reflow post primary PCI in STEMI patients.(OR 2.356, 95% CI 1.201-5.945;P=0.030). The area under the ROC curve for the LMR was 0.757 [95% confidence interval(CI) 0.686-0.828, P<0.001]. Conclusions LMR at admission could serve as a biomarker for no-reflow phenomenon in patients undertaken primary PCI for STEMI.[S Chin J Cardiol 2019;20(4):228-235]

Intracoronary pressure gradient measurement in acute myocardial infarction patients with the no-reflow phenomenon during primary percutaneous coronary intervention

Background:Various experimental and clinical studies have reported on coronary microcirculatory dysfunction("no-reflow"phenomenon).Nevertheless,pathogenesis and effective treatment are yet to be fully elucidated.This study aimed to measure the intracoronary pressure gradient in the no-reflow artery during emergent percutaneous coronary intervention and explore the potential mechanism of no-reflow.Methods:From September 1st,2018 to June 30th,2019,intracoronary pressure in acute myocardial infarction patient was continuously measured by aspiration catheter from distal to proximal segment in the Department of Coronary Care Unit,Tianjin Chest Hospital,respectively in no-reflow arteries(no-reflow group)and arteries with thrombolysis in myocardial infarction-3 flow(control group).At least 12 cardiac cycles were consecutively recorded when the catheter was pulled back.The forward systolic pressure gradient was calculated as proximal systolic pressure minus distal systolic pressure.Comparison between groups was made using the Student t test,Mann-Whitney U-test or Chi-square test,as appropriate.Results:Intracoronary pressure in 33 no-reflow group and 26 in control group were measured.The intracoronary forward systolic pressure gradient was-1.3(-4.8,0.7)and 3.8(0.8,8.8)mmHg in no-reflow group and control group(Z=-3.989,P<0.001),respectively,while the forward diastolic pressure gradient was-1.0(-3.2,0)and 4.6(0,16.5)mmHg in respective groups(Z=-3.851,P<0.001).Moreover,the intracoronary forward pressure gradient showed significant difference between that before and after nicorandil medication(Z=-3.668,P<0.001 in systolic pressure gradient and Z=-3.530,P<0.001 in diastolic pressure gradient).Conclusions:No reflow during emergent coronary revascularization is significantly associated with local hemodynamic abnormalities in the coronary arteries.Intracoronary nicorandil administration at the distal segment of a coronary artery with an aspiration catheter could improve the microcirculatory dysfunction and resume normal coronary pressure gradient.Clinical trial registration:www.ClinicalTrials.gov(No.NCT 03600259).

Correction of dynamic Brazilian disc tensile strength of rocks under preloading conditions considering the overload phenomenon and invoking the Griffith criterion

Dynamic tensile failure is a common phenomenon in deep rock practices,and thus accurately evaluating the dynamic tensile responses of rocks under triaxial pressures is of great significance.The Brazilian disc(BD)test is the suggested method by the International Society for Rock Mechanics and Rock Engineering(ISRM)for measuring both the static and dynamic tensile strengths of rock-like materials.However,due to the overload phenomenon and the complex preloading conditions,the dynamic tensile strengths of rocks measured by the BD tests tend to be overestimated.To address this issue,the dynamic BD tensile strength(BTS)of Fangshan marble(FM)under different preloading conditions were measured through a triaxial split Hopkinson pressure bar(SHPB).The fracture onset in BD specimen was captured through a strain gage around the disc center.The discrepancy between the traditional tensile strength(TTS,determined by the peak load P_(f) of the BD specimen)and the nominal tensile strength(NTS,obtained from the load P_(i) when the diametral fracture commences in the tested BD specimen)was applied to quantitatively evaluating the overload phenomenon.The Griffith criterion was used to rectify the calculation of the tensile stress at the disc center under triaxial stress states.The results demonstrate that the overload ratio(s)increases with the loading rate(σ)and decreases with the hydrostatic pressure(σ_(s)).The TTS corrected by the Griffith criterion is independent of theσ_(s)due to the overload phenomenon,while the NTS corrected by the Griffith criterion is sensitive to both the andσ.Therefore,it is essential to modify the tensile stress in dynamic confined BD tests using both the overload correction and the Griffith criterion rectification to obtain the accurate dynamic BTS of rocks.

Asymmetric Environmental Regulation:Mechanism and a Yardstick Phenomenon

In discussing the policy effects of environmental regulation,we should focus not only on whether environmental regulation helps improve the environmental and economic performance of firms,but also on how such improvement is materialized,i.e.whether the obsolete mode of production is reversed.After matching the database of China’s industrial enterprises with that of pollution emissions from these industrial enterprises,this paper identifies the asymmetric scope of clean production standards to test the effect of environmental regulation on the total factor productivity(TFP)of the industrial enterprises.Our empirical research finds that the implementation of clean production standards may induce TFP improvement.However,such improvement only occurs for polluters who cannot or who barely meet clean production standards and does little to improve the production standards of polluters with low pollution emission,reflecting the yardstick phenomenon of the asymmetric environmental regulation policy effect:While polluters are forced to improve,clean enterprises that pollute less are more likely to take no action.Further research finds that such TFP improvement is materialized primarily by means of overall firm optimization;the compensation effect is insignificant and does not reverse the backward mode of production.Polluters cope with the implementation of clean production standards by purchasing more equipment and expanding capacity,which adds to the tension between the expansion of capacity and the abatement of pollution emission.

Medical and interventional therapy of Kasabach-Merritt phenomenon associated with Kaposiform hemangioendothelioma:A case report

An infant with Kasabach-Merritt Phenomenon(KMP)presented with a giant subcutaneous mass in the right lower limb,severe hypofibrinogenemia,and thrombocytopenia.Glucocorticoids,along with supportive treatments including transfusion of blood products and clotting factors,were administered to reverse fatal disseminated intravascular coagulation and acute hemolysis.The glucocorticoid dose was tapered slowly,and sirolimus was added to treat the hemangiomas.The patient subsequently underwent interventional therapy.After 6 months of medical and interventional therapy,the patient was doing well with a normal platelet count,the tumor volume was markedly reduced,and the primary cutaneous lesion became pale pink.Currently,the patient remains on sirolimus,and no recurrence of thrombocytopenia or further growth of the mass was observed after six months of follow-up.

Anesthetic management of a patient with preoperative R-on-T phenomenon undergoing laparoscopic-assisted sigmoid colon resection:A case report

BACKGROUND The R-on-T phenomenon is a malignant arrhythmia associated with potentially catastrophic consequences.It may initiate ventricular tachycardia or ventricular fibrillation,which can result in syncope or sudden cardiac death.This manifestation poses a great challenge for anesthesiologists.However,it is rarely encountered in the perioperative setting.CASE SUMMARY We herein present a case in which the R-on-T phenomenon was incidentally revealed by 24-h Holter monitoring in a patient diagnosed with sigmoid colon cancer.Careful evaluation and treatment with mexiletine were carried out preoperatively under consultation with a cardiovascular specialist,and surgery was uneventfully performed under general anesthesia after thorough preparation.CONCLUSION Physicians should be vigilant about this infrequent but potentially fatal arrhythmia.Our experience suggests that the anesthetic process can be greatly optimized with careful preparation.

符号互动:品牌数字传播的社会认同建构

网络化个体主义是推动品牌社会认同加速离散的重要力量,由此造成品牌社会认同的危机,然而,网络个体的重新聚集也成为品牌构建新社会认同的契机。因此,探索全新的品牌数字传播对社会认同的建构理路,对于理解广告品牌研究的理论与实践具有重要意义。研究基于符号互动理论,对“后浪现象”这一数字传播典型案例进行探讨,从个体、群际和社会三重互动情境着手分析,提炼出品牌数字传播构建社会认同的两个关键环节:“情感化的符号生产”与“仪式化的公众文本创作”。在个体间情感认同形成层面,符号的生产促成情感心理空间的连接和扩大,其是形成情感认同的中间纽带;在群际间层面,人们通过互动仪式链参与公众文本创作,促进群际间的意义生产,突破圈层的意义边界,助力群际间认同。

当代大学生消极苦乐观的表征解析、疗愈理论与教育对策——以“摆烂”现象为例

苦乐观是人生观的重要组成部分,体现了个体对自我生存意义的探寻,而当前部分大学生的“摆烂”现象反映了其苦乐观的消极倾向。通过对当代大学生的“摆烂”现象进行分析,可以发现部分大学生在苦乐观方面存在以下表征:片面理解苦乐内涵与关系的怀疑倾向,苦乐态度不端与情感消极为表征的颓废悲观倾向,苦乐信念缺乏与意志薄弱的精神虚无倾向以及苦乐动机功利与行为脱节的精致利己主义倾向。借助积极心理学相关理论探讨大学生苦乐观教育,有助于消解大学生“摆烂”症候,帮助大学生辩证对待人生苦乐矛盾,树立积极向上的苦乐观。

乙型肝炎病毒检测方法的现状研究

HBV感染是我国最主要的传染性疾病之一,目前临床主要使用体外诊断试剂对该病毒进行准确快速的检测,体外诊断试剂盒的方法学主要包括:免疫学方法和分子生物学方法。本文通过PubMed(检索时限自2017年1月至2023年12月)和万方数据库(检索时限自2017年1月至2023年12月)检索乙型肝炎病毒(hepatitis B virus,HBV)的检测方法、相关试剂盒的生产和临床应用的相关文献,详细列举最新检测方法的进展并比较不同方法学的优缺点,全面分析和讨论了我国目前乙型肝炎病毒检测的现状和研究进展。研究发现,我国HBV检测用商品化试剂盒的方法学分布存在集中现象,试剂盒的生产存在“东部多,西部少,大分散,小聚集”的特点。

我国闭坑煤矿矿井水水质演化研究进展与展望

随着我国煤矿矿井关闭数量的逐渐增加,闭坑矿井水水质恶化和污染问题日益突出,准确掌握闭坑矿井水水质演化规律及机制,是目前闭坑矿山可持续绿色发展的重大科学难题,也是地下水污染有效防控和水资源合理开发利用的重要前提。在回顾关闭矿井发展历史的基础上,首先阐述了我国关闭矿井的分布情况,之后分别对闭坑矿井水水质特征、水质演化规律及水质演化的多场作用等方面展开综述,最后对我国闭坑矿井水水质研究中存在的关键问题和应用方向进行了展望。研究结果表明:①截至2023年底,我国关闭矿井的数量已经上升到13000多个,主要分布在山西、河南、河北、山东、江苏和安徽北部等地区;②我国部分闭坑矿井水的pH、矿化度、硫酸盐、氟化物和铁锰重金属等水质指标含量超过Ⅲ类水标准,其中酸性矿井水(pH<6.5)主要分布在云贵、鲁西、山西等地区,高矿化度矿井水(TDS>1000 mg/L)主要分布在鲁西、山西、河南、两淮、蒙东、宁东、新疆等地区,硫酸盐矿井水(硫酸盐质量浓度>250 mg/L)主要分布在云贵、鲁西、山西、蒙东、宁东、神东、新疆哈密等地区,氟化物矿井水(F质量浓度>1.0 mg/L)主要分布在两淮、山西、神东等地区,铁锰重金属矿井水(Fe质量浓度>0.3 mg/L、Mn质量浓度>0.1 mg/L)主要分布在云贵、鲁西、山西、蒙东等地区。③在闭坑矿井被完全淹没之前,其水质在空间上会出现明显的分层现象,即浅部的优质水层、中部的过渡水层和深部的劣质水层,这主要与矿井采掘空间分布、地温梯度和盐度等因素有关。④煤矿关闭后,矿井水水质的演变过程大致可分为3个阶段,第Ⅰ阶段为矿井水中典型污染物(硫酸盐和铁离子)质量浓度快速上升达并到峰值阶段,第Ⅱ阶段为污染物浓度快速下降阶段,第Ⅲ阶段为矿井水水质与邻近含水层地下水水质背景值相同并保持相对稳定阶段。⑤系统总结了我国闭坑矿井水动力场、水化学场、微生物场和温度场的研究进展,指出了闭坑矿井多相(水−岩−气−生)多场(水化学场−水动力场−微生物场−温度场)耦合作用机制的研究还不充分。⑥提出了我国闭坑矿井水水质演化问题的研究仍然面临着水质演化规律和水质演化机制不清楚等关键科学问题。

任务协作表示增强的要素及关系联合抽取模型

对文本中诸如实体与关系、事件及其论元等要素及其特定关系的联合抽取是自然语言处理的一项关键任务.现有研究大多采用统一编码或参数共享的方式隐性处理任务间的交互,缺乏对任务之间特定关系的显式建模,从而限制模型充分利用任务间的关联信息并影响任务间的有效协同.为此,提出了一种基于任务协作表示增强的要素及关系联合抽取模型(Task-Collaboration Representation Enhanced model for joint extraction of elements and relationships,TCRE).该模型旨在从多个阶段处理任务间的特定关系,帮助子任务进行更细致的调节和优化,促进整体性能的提升.在三个关系抽取和一个事件抽取数据集上进行实验,TCRE在实体识别和关系提取任务上平均性能分别提高0.57%和0.77%,在触发词识别和论元角色分类任务上分别提高0.7%和1.4%.此外,TCRE还显示出在缓解“跷跷板现象”方面的作用.

复合润滑结构改善滑动导轨表面爬行现象研究

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