小影像Koch三角及其房室结射频消融应注意的问题

为探讨小影像Koch三角房室结折返性心动过速 (AVNRT)病人射频消融时应注意的问题 ,右前斜位 30°透视下 ,将最大希氏束 (HBE)电位记录处与冠状静脉窦口 (CSo)处的影像距离容纳不下 3个 8F加硬大头电极者定义为小影像Koch三角 ,对 16例小影像Koch三角的AVNRT病人 ,参照慢径消融法行射频消融。结果 :16例病人中 ,成功消融靶点位于CSo水平以下者 12例 ,与CSo位于同一水平者 3例 ,位于CSo水平以上者 1例。 16例病人经消融后房室传导跳跃现象消失者 14例 ;跳跃现象存在 ,但无心房回波 ,异丙肾上腺素亦不能诱发AVNRT者 2例。上述 12例中有 1例于术中出现一过性房室阻滞 (AVB) ,术后 2 4h发生Ⅱ度Ⅱ型AVB ,出院后随访 3个月未能恢复正常 ,因心率为 38～ 5 0次 /分 ,并伴有脑供血不足症状 ,遂置入永久心脏起搏器。其余病人经过 3.5± 1.2 (0 .5～ 5 )年的随访 ,无AVNRT复发 ,亦无AVB发生。结论 :对于小影像Koch三角AVNRT病人的射频消融 ,应突破常规消融时的区位划分概念 ,主要在CSo前下方寻找并消融慢径 ,并根据放电后反应及时调整消融参数。     

桑仙降压颗粒对自发性高血压大鼠心肌VEGF及nm23的干预

[目的]观察桑仙降压颗粒对自发性高血压大鼠(SHR)心肌血管内皮生长因子(VEGF)及nm23的影响,探讨其对高血压病心肌血管生长促进因子、抑制因子的干预作用。[方法]SHR随机分为3组,空白对照组、吲哒帕胺西药对照组、桑仙降压颗粒组,以Wistar大鼠为正常对照,4周及8周后观察SHR心肌VEGF及nm23的表达。[结果]实验前正常对照组与空白对照组相比VEGF及nm23蛋白光密度值差异均无统计学意义。实验4、8周后相较空白对照组,桑仙降压颗粒组VEGF表达明显增多而nm23蛋白密度值显著减少。[结论]桑仙降压颗粒能增强VEGF的表达及降低nm23的蛋白密度值。     

Local cutaneous nerve terminal and mast cell responses to manual acupuncture in acupoint LI4 area of the rats

Previous studies have shown that the effects of manual acupuncture (MA) are contributed by collagen fibers and mast cells in local acupoints, at which acupuncture stimulation causes various afferent fiber groups to be excited. However what happens in local nerve fibers and mast cells after MA remains unclear. The aim of this study was to examine the response of cutaneous nerve fibers and mast cells to MA stimulation in acupoint Hegu (LI4). The contralateral LI4 of the same rat was used as a non-stimulated control. Immnohistochemistry analysis were carried out to observe the expression of histamine (HA), serotonin (5-HT) and nociceptive neuropeptides, calcitonin gene-related peptide (CGRP) and substance P (SP), in the LI4 area. Mast cells were labeled with anti-mast cell tryptase antibody and simultaneously with HA or 5-HT primary antibodies to observe their co-expression. Our results showed that SP and CGRP were expressed more highly on the cutaneous nerve fibers of LI4 after MA stimulation than that of the control. Mast cells aggregated in close proximity to the blood vessels in intra-epidermis and dermis and some of them with degranulation in the lower dermis and subcutaneous tissue of LI4. Both mast cells and their granules appeared with HA (+) and 5-HT (+) expression at stimulated L14 sites, while a few intact mast cells with a little expression of 5-HT and HA were distributed in areas of non-stimulated L14. The results indicated that local cutaneous nerve terminals and mast cells responded to MA with higher expression of SP and CGRP in nerve fibers, as well as with aggregation and degranulation of mast cells with HA and 5-HT granules at acupoint LI4. These neuroactive substances may convey signals to certain pathways that contribute to the effects of acupuncture.     

Dynamics revelation of conformational changes and binding modes of heat shock protein 90 induced by inhibitor associations

Heat shock protein 90 (Hsp90) has been an attractive target of potential drug design for antitumor treatment. The current work integrates molecular dynamics (MD) simulations, calculations of binding free energy, and principal component (PC) analysis with scanning of inhibitor–residue interaction to probe the binding modes of inhibitors YK9, YKJ and YKI to Hsp90 and identify the hot spot of the inhibitor–Hsp90 binding. The results suggest that the introductions of two groups G1 and G2 into YKJ and YKI strengthen the binding ability of YKJ and YKI to Hsp90 compared to YK9. PC analysis based MD trajectories prove that inhibitor bindings exert significant effects on the conformational changes, internal dynamics and motion modes of Hsp90, especially for the helix α2 and the loops L1 and L2. The calculations of residue-based free energy decomposition and scanning of the inhibitor–Hsp90 interaction suggest that six residues L107, G108, F138, Y139, W162 and F170 construct the common hot spot of the inhibitor–residue interactions. Moreover the substitutions of the groups G1 and G2 in YKJ and YKI lead to two additional hydrogen bonding interactions and multiple hydrophobic interactions for bindings of YKJ and YKI to Hsp90. This work is also expected to contribute theoretical hints for the design of potent inhibitors toward Hsp90.

Heat shock protein 90 (Hsp90) has been an attractive target of potential drug design for antitumor treatment.     

Cardiovascular events and all-cause mortality in patients with type 2 diabetes treated with dipeptidyl peptidase-4 inhibitors: An extensive meta-analysis of randomized controlled trials

AimsMeta-analyses of randomized trials on Dipeptidyl Peptidase-4 inhibitors (DPP4i) reported discordant results on major cardiovascular events (MACE), mortality, and heart failure. Aim of this meta-analysis of randomized trials is the assessment of the cardiovascular safety of DPP4i.Data synthesisA Medline, Embase, Cochrane database search for sitagliptin, vildagliptin, omarigliptin, saxagliptin, alogliptin, trelagliptin, anagliptin, linagliptin, gemigliptin, evogliptin, and teneligliptin was performed up to up January 1st, 2020. All trials with a duration ≥24 weeks and comparing the effects of DPP4i with placebo or active drugs were collected. Mantel–Haenszel odds ratio (MH-OR) with 95% Confidence Interval (95% CI) was calculated for all outcomes defined above. A total of 182 eligible trials were identified. DPP-4i were not associated with an increased risk of MACE (MH-OR 0.99 [0.93, 1.04]), all-cause mortality (MH-OR 0.99 [0.93, 1.06]), and heart failure (MH-OR 1.05 [0.96, 1.15]) with no significant differences across individual molecules, except for saxagliptin, which was associated with an increased risk of heart failure.ConclusionsAs a class, DPP4i are not associated with any increase or reduction of MACE, all-cause mortality, and heart failure. Saxagliptin seems to be associated with an increased risk of hospitalization for heart failure.     

Localization and radiofrequency ablation of slow conducting pathway in left free wall

Objectives To study the Electrophysiologic characteristics and method of radiofrequency ablation in patients with slow conduction in left free wall. Methods When 5 cases induced tachycardia, using VS2 program stimulation terminated the tachycardia to establish that ventricle is the part of reentry circle. Results No retrograde A waves in 4 cases but only 1 case present A wave in terminating tachycardia. The accessory pathways have decreasing conduction in One case. Successful ablation were located in ventricle sides. Conclusions Ventricular sense and S2 program stimulation to terminate tachycardia is a reliable method to different atrial tachycardia . A wave of successful targets ahead of A wave of any coronary sinus leads is 8 -22 ms.     

高碘地区防治监测指标优化研究

目的了解高碘地区停供碘盐状况及对重点人群碘营养的影响,为制定高碘监测方案提供依据。方法每个县的高碘地区分布及食盐供应情况,将其分为单纯高碘、高碘和非高碘共存即“混杂地区”、全部停供碘盐、碘盐和无碘盐共存4种地区类型,分别进行分层抽样监测。每个层次均按东、西、南、北、中随机抽取9个乡镇,每个乡镇随机抽取4个村。每个村抽取8户居民半定量检测食盐样,同时抽取其中4户各采1名家庭妇女随意尿样检测尿碘。不足9个乡镇的层次,每个村抽取15户居民盐样。不足5个乡镇的全部监测。每类地区各选择1所乡镇小学和1所农村小学,整群抽取100名儿童检查甲状腺,检测随意尿样尿碘,由本人检测自带家中食盐。结果调查了3个县市的31个乡镇的121个村。高碘地区19个乡镇,非高碘地区12个乡镇。共检测居民户食盐1354份,碘盐率45.6%,无碘盐率54.4%。高碘地区碘盐率32.6%,无碘盐率67.4%;非高碘地区碘盐率70.1%,非碘盐率29.9%。检测妇女和儿童尿样1660份,尿碘（UI）水平（474.7±391.5）μg/L,尿碘中位数（MUI）354.7μg/L。妇女MUI为449.3μg/L,UI〈100μg/L的样本比例占5.6%、100～300μg/L的占30.0%、〉300μg/L的占64.4%;儿童MUI为321.44μg/L,UI〈100μg/L的样本比例占6.0%、100～300μg/L的占39.8%、〉300μg/L的占54.2%。妇女与儿童的MUI差异有统计学意义。高碘地区MUI为409.1μg/L,非高碘地区MUI为305.2μg/L,二者差异有统计学意义。3个县市甲状腺肿大率分别为2.2%、11.5%和3.0%。结论无碘盐率体现干预效果,尿碘反映碘营养水平,建议高碘地区以居民户食盐和妇女尿碘为主要监测指标,并实行分层抽样监测。     

氟对小鼠胸腺及上皮细胞形态与功能的影响

目的研究氟化物对胸腺上皮细胞的毒性作用及对胸腺细胞发育的影响,探讨其作用机制。方法采用小鼠胸腺上皮细胞原代体外培养及与胸腺细胞混合培养技术,观察不同剂量氟化钠(NaF)对小鼠胸腺上皮细胞形态与功能的损伤情况及胸腺细胞在NaF处理的小鼠胸腺上皮细胞环境中的生长发育状况。结果染氟组可见小鼠胸腺上皮细胞胞体变圆,折光性增强,胞浆内有空泡形成,小鼠胸腺上皮细胞培养基中乳酸脱氢酶(LDH)活性增强,胸腺上皮细胞合成DNA和蛋白质的能力降低,白细胞介素1(IL-1)分泌量减少,并呈一定的剂量反应关系。不同剂量NaF处理的小鼠胸腺上皮细胞与新鲜的胸腺细胞混合培养,随着染氟剂量的增加,胸腺细胞摄取3H-Tdr和3H-Leu的能力降低,活细胞数目逐渐减少。结论高氟能够直接损伤小鼠胸腺上皮细胞、破坏胸腺微环境,进而导致胸腺细胞发育障碍,影响免疫功能。