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Catheter ablation is currently the only curative treatment for scar-related ventricular tachycardias (VTs). However, not only are ablation procedures long, with relatively high risk, but success rates are punitively low, with frequent VT recurrence. Personalized in-silico approaches have the opportunity to address these limitations. However, state-of-the-art reaction diffusion (R-D) simulations of VT induction and subsequent circuits used for in-silico ablation target identification require long execution times, along with vast computational resources, which are incompatible with the clinical workflow. Here, we present the Virtual Induction and Treatment of Arrhythmias (VITA), a novel, rapid and fully automated computational approach that uses reaction-Eikonal methodology to induce VT and identify subsequent ablation targets. The rationale for VITA is based on finding isosurfaces associated with an activation wavefront that splits in the ventricles due to the presence of an isolated isthmus of conduction within the scar; once identified, each isthmus may be assessed for their vulnerability to sustain a reentrant circuit, and the corresponding exit site automatically identified for potential ablation targeting. VITA was tested on a virtual cohort of 7 post-infarcted porcine hearts and the results compared to R-D simulations. Using only a standard desktop machine, VITA could detect all scar-related VTs, simulating activation time maps and ECGs (for clinical comparison) as well as computing ablation targets in 48 minutes. The comparable VTs probed by the R-D simulations took 68.5 hours on 256 cores of high-performance computing infrastructure. The set of lesions computed by VITA was shown to render the ventricular model VT-free. VITA could be used in near real-time as a complementary modality aiding in clinical decision-making in the treatment of post-infarction VTs. 相似文献
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《Obesity research & clinical practice》2022,16(2):106-114
BackgroundChildhood obesity places a major burden on global public health. We aimed to identify and characterize potential factors, both individually and jointly, in association with overweight and obesity in Chinese preschool-aged children.MethodsWe cross-sectionally recruited 9501 preschool-aged children from 30 kindergartens in Beijing and Tangshan. Overweight and obesity are defined according to the World Health Organization (WHO), International Obesity Task Force (IOTF), and China criteria.ResultsAfter multivariable adjustment, eating speed, sleep duration, birthweight, and paternal body mass index (BMI) were consistently and significantly associated with childhood overweight and obesity under three growth criteria at a significance level of 5%. Additional fast food intake frequency, maternal BMI, gestational weight gain (GWG) and maternal pre-pregnancy BMI were significant factors for overweight (WHO criteria) and obesity (both IOTF and China criteria). Importantly, there were significant interactions between parental obesity and eating speed for childhood obesity. Finally, for practical reasons, risk nomogram models were constructed for childhood overweight and obesity based on significant factors under each criterion, with good prediction accuracy.ConclusionOur findings indicated a synergistic association of lifestyle, fetal and neonatal, and family-related factors with the risk of experiencing overweight and obesity among preschool-aged children. 相似文献
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目的基于人类免疫缺陷病毒Ⅰ型(HIV-1)感染者外周血单个核细胞(PBMCs)中HIV-1总DNA和RNA定量检测结果对感染细胞内病毒的转录活性进行区分。方法采集2017年10月至2018年12月于哈尔滨医科大学附属第四医院感染科就诊的HIV-1感染者血液样本,分离PBMCs细胞,采用PCR荧光探针法对PBMCs细胞内HIV-1总DNA和RNA进行定量检测,并计算两者比值(Ratio)。根据Ratio值筛选出HIV-1转录活跃组样本和相对非活跃组样本,另外选择健康人PBMCs样本作为对照组。对3组样本进行基因转录组表达谱检测以及人口特征差异性检验,并对基因表达谱检测结果进行主成分分析以验证对3组样本病毒转录活性区分的准确性。结果从60例感染HIV-1患者的PBMCs样本中筛选出HIV-1转录活跃组样本(10例)和相对非活跃组样本(11例),另外选择6例健康人PBMCs样本作为对照组。其中转录活跃组样本Ratio值为165.2~738.93,平均为(339.27±189.68);相对非活跃组Ratio值为4.67~42.39,平均为(17.65±11.78)。转录活跃组和相对非活跃组样本间的CD4+T细胞计数(P=0.049)和Ratio值(P<0.001)差异均具有统计学意义;3组样本年龄(P=0.989)和性别(P=0.650)分布差异无统计学意义。对3组样本的PBMCs基因表达谱主成分分析结果显示:对照组与HIV-1感染者(包括转录活跃组和相对非活跃组)间区分明显。转录活跃组和相对非活跃组间有部分样本重合,同时结果也显示当HIV-1感染者的CD4+T淋巴细胞计数与健康人无显著差异时,其细胞内的基因表达与健康人接近。结论基于HIV-1总DNA和RNA定量检测结果及两者间比值可以较好地区分PBMCs内病毒转录活性。HIV-1感染细胞内部病毒的不同转录激活状况可导致其基因表达谱的异质性。 相似文献
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《Acta histochemica》2022,124(2):151860
Objective To explore the preliminary application method and diagnostic value of virtual touch tissue imaging quantification (VTIQ) in diffuse testicular diseases of male infertility. A total of 70 male examiners in our hospital from June 2019 to March 2020 were selected as the research objects. According to whether the subjects are sick (testicular microlithiasis, varicocele), all subjects are divided into three groups: normal group, testicular microlithiasis group, and varicocele group. Whether there is a difference between the groups, and analyze whether there is a correlation between the index reflecting the quality of the semen and the testicular shear wave velocity. The measurement of different positions in the testis will affect the magnitude of the shear wave velocity (P < 0.05). The shear wave velocities of the testes of different diseases are obviously different from the normal side. At the same time, postural changes will have a certain impact on the shear wave velocities of both testes (all P < 0.05). There is a certain correlation between the testicular shear wave velocity and the conventional semen quality index (total sperm motility (P < 0.05)) of the subjects. Acoustic palpation tissue imaging quantitative technology can be applied to the diagnosis of male testes and testicular-related diseases (especially diffuse testicular diseases), and is more suitable for male infertility, which can provide clinical diagnosis and treatment options certain imaging basis. 相似文献
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目的:观察银杏叶胶囊对脑卒中后轻度认知障碍患者认知功能及预后的影响。方法:选择100例脑卒中后轻度认知障碍患者,按随机数字表法分为观察组和对照组各50例。对照组给予西医对症治疗,观察组在对照组基础上给予银杏叶胶囊治疗。比较2组治疗前后蒙特利尔认知评估量表(MoCA)评分、脑部动脉血流速度、脑动脉硬化发生率、血管痉挛发生率以及血管狭窄发生率。结果:治疗前,2组MoCA评分比较,差异无统计学意义(P>0.05)。治疗后,2组MoCA评分均较治疗前升高(P<0.05),且观察组MoCA评分高于对照组(P<0.05)。治疗后,观察组大脑前动脉(ACA)、大脑中动脉(MCA)、大脑后动脉(PCA)、椎动脉(VA)、基底动脉(BA)的血流速度明显快于对照组(P<0.05)。治疗后,观察组脑动脉硬化发生率、血管痉挛发生率以及血管狭窄发生率均低于对照组(P<0.05)。结论:银杏叶胶囊可以改善脑卒中后轻度认知障碍患者的认知功能和脑部血流,降低血管狭窄发生率,临床疗效较好。 相似文献
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《Clinical neurophysiology》2021,132(4):967-974
ObjectiveChronic fatigue syndrome (CFS) and fibromyalgia (FM) are disorders of unknown etiology and unclear pathophysiology, with overlapping symptoms of – especially muscular –fatigue and pain. Studies have shown increased muscle fiber conduction velocity (CV) in the non-painful muscles of FM patients. We investigated whether CFS patients also show CV abnormalities.MethodsFemales with CFS (n = 25), with FM (n = 22), and healthy controls (n = 21) underwent surface electromyography of the biceps brachii, loaded up to 20% of maximum strength, during short static contractions. The mean CV and motor unit potential (MUP) velocities with their statistical distribution were measured.ResultsThe CV changes with force differed between CFS-group and both FM-group and controls (P = 0.01). The CV of the CFS-group increased excessively with force (P < 0.001), whereas that of the controls increased only slightly and non-significantly, and that of the FM-group did not increase at all. In the CFS-group, the number of MUPs conveying very high conduction velocities increased abundantly with force and the MUPs narrowed.ConclusionOur results suggest disturbed muscle membrane function in CFS patients, in their motor units involved in low force generation. Central neural deregulation may contribute to this disturbance.SignificanceThese findings help to detangle the underlying mechanisms of CFS. 相似文献
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目的探究黄连Coptidis Rhizoma在连栀矾溶液传统发酵炮制中的作用。方法按照连栀矾溶液传统配方比例,将其拆分为3组配方溶液:连栀矾组(黄连+栀子+白矾)、黄连组(黄连+白矾)和栀子组(栀子+白矾),采用HPLC分析比较3组溶液发酵前后的化学成分变化轮廓,采用Illumina Hiseq高通量测序技术测定并比较发酵溶液中微生物的群落特征。结果传统配方连栀矾经发酵后环烯醚萜类成分发生了较显著的变化(P<0.05),生物碱类成分未发生明显变化,拆分后的黄连组中生物碱类成分和栀子组中环烯醚萜类成分均没有发生明显变化。分别对各组发酵溶液进行测序,根据α多样性分析结果,3组发酵液中真菌多样性为连栀矾组<栀子组<黄连组,真菌的丰富度为栀子组<连栀矾组<黄连组;细菌多样性为连栀矾组<黄连组<栀子组,细菌的丰富度为连栀矾组<栀子组<黄连组。根据β多样性分析结果,3组溶液中的真菌和细菌的群落结构均有明显差异。根据微生物相对丰度分析可知,3组的优势真菌均为子囊菌门、担子菌门和罗兹菌门,不同组间丰度无明显差异;真菌优势属中的孢霉属的丰度在连栀矾组最高,显著高于另外2组(P<0.05),栀子组又显著高于黄连组(P<0.05);韦斯特壳属的丰度在连栀矾组中最低,显著低于黄连组和栀子组(P<0.05),后两者间丰度无明显差异。3组的优势细菌均为变形菌门、厚壁菌门、放线菌门和拟杆菌门,其中连栀矾组中变形菌门的丰度极显著低于黄连组和栀子组(P<0.01),厚壁菌门的丰度在连栀矾组中极显著高于黄连组和栀子组(P<0.01),放线菌门和拟杆菌门的丰度在3组发酵溶液的差异较小;细菌优势菌属中的乳杆菌属在连栀矾组中显著高于黄连组和栀子组(P<0.05),在黄连组中也显著高于栀子组(P<0.05),伯克氏菌属丰度在黄连组和栀子组中无显著差异,都显著高于连栀矾组中的丰度(P<0.05)。结论连栀矾溶液配方中的黄连能提高其中栀子的有效成分的发酵转化,并且是通过对发酵体系中的优势菌属的丰度进行调节而发挥作用的。进一步佐证了传统配方制剂的合理性和科学性。 相似文献