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11.
《Journal of Cardiovascular Computed Tomography》2021,15(6):492-498
BackgroundCompared with invasive fractional flow reserve (FFR), coronary CT angiography (cCTA) is limited in detecting hemodynamically relevant lesions. cCTA-based FFR (CT-FFR) is an approach to overcome this insufficiency by use of computational fluid dynamics. Applying recent innovations in computer science, a machine learning (ML) method for CT-FFR derivation was introduced and showed improved diagnostic performance compared to cCTA alone. We sought to investigate the influence of stenosis location in the coronary artery system on the performance of ML-CT-FFR in a large, multicenter cohort.MethodsThree hundred and thirty patients (75.2% male, median age 63 years) with 502 coronary artery stenoses were included in this substudy of the MACHINE (Machine Learning Based CT Angiography Derived FFR: A Multi-Center Registry) registry. Correlation of ML-CT-FFR with the invasive reference standard FFR was assessed and pooled diagnostic performance of ML-CT-FFR and cCTA was determined separately for the following stenosis locations: RCA, LAD, LCX, proximal, middle, and distal vessel segments.ResultsML-CT-FFR correlated well with invasive FFR across the different stenosis locations. Per-lesion analysis revealed improved diagnostic accuracy of ML-CT-FFR compared with conventional cCTA for stenoses in the RCA (71.8% [95% confidence interval, 63.0%–79.5%] vs. 54.8% [45.7%–63.8%]), LAD (79.3 [73.9–84.0] vs. 59.6 [53.5–65.6]), LCX (84.1 [76.0–90.3] vs. 63.7 [54.1–72.6]), proximal (81.5 [74.6–87.1] vs. 63.8 [55.9–71.2]), middle (81.2 [75.7–85.9] vs. 59.4 [53.0–65.6]) and distal stenosis location (67.4 [57.0–76.6] vs. 51.6 [41.1–62.0]).ConclusionIn a multicenter cohort with high disease prevalence, ML-CT-FFR offered improved diagnostic performance over cCTA for detecting hemodynamically relevant stenoses regardless of their location. 相似文献
12.
《Clinical neurophysiology》2021,132(12):3104-3115
ObjectiveWe aimed to establish an objective neurophysiological test protocol that can be used to assess the somatosensory nervous system.MethodsIn order to assess most fiber subtypes of the somatosensory nervous system, repetitive stimuli of seven different modalities (touch, vibration, pinprick, cold, contact heat, laser, and warmth) were synchronized with the electroencephalogram (EEG) and applied on the cheek and dorsum of the hand and dorsum of the foot in 21 healthy subjects and three polyneuropathy (PNP) patients. Latencies and amplitudes of the modalities were assessed and compared. Patients received quantitative sensory testing (QST) as reference.ResultsWe found reproducible evoked potentials recordings for touch, vibration, pinprick, contact-heat, and laser stimuli. The recording of warm-evoked potentials was challenging in young healthy subjects and not applicable in patients. Latencies were shortest within Aβ-fiber-mediated signals and longest within C-fibers. The test protocol detected function loss within the Aβ-fiber and Aδ-fiber-range in PNP patients. This function loss corresponded with QST findings.ConclusionIn this pilot study, we developed a neurophysiological test protocol that can specifically assess most of the somatosensory modalities. Despite technical challenges, initial patient data appear promising regarding a possible future clinical application.SignificanceEstablished and custom-made stimulators were combined to assess different fiber subtypes of the somatosensory nervous system using modality-specific evoked potentials. 相似文献
13.
Roberto V.P. Ribeiro Mitesh V. Badiwala Danny Ramzy Laura C. Tumiati Vivek Rao 《The Journal of thoracic and cardiovascular surgery》2019,157(2):615-625.e1
Objective
Hypertonic saline (HTS) has potent immune and vascular effects. We assessed recipient pretreatment with HTS on allograft function in a porcine model of heart transplantation and hypothesized that HTS infusion would limit endothelial and left ventricular (LV) dysfunction following transplantation.Methods
Heart transplants were performed after 6 hours of cold ischemic storage. Recipient pigs were randomized to treatment with or without HTS (7.5% NaCl) before cardiopulmonary bypass (CPB). Using a myograft apparatus, coronary artery endothelial-dependent (Edep) and -independent (Eind) relaxation was assessed. LV performance was determined using pressure-volume loop analysis. Pulmonary interleukin (IL)-2, IL-6, and tumor necrosis factor (TNF)-α expression was measured.Results
Weaning from CPB and LV performance after transplantation were improved in HTS-treated animals. Successful weaning from CPB was greater in the HTS-treated hearts (8 of 8 vs 2 of 8; P < .05). Mean LV functional recovery was improved in the HTS-treated animals, as assessed by preload recruitable stroke work (65 ± 10% vs 27 ± 10%; P < .001) and end-systolic elastance (55 ± 7% vs 37 ± 4%; P < .001). Treatment with HTS resulted in improved Edep (mean maximum elastance [Emax], 56 ± 5% vs 37 ± 7%; P < .001) and Eind (mean Emax%, 77 ± 6% vs 52 ± 4%; P < .001) vasorelaxation compared with control. Pulmonary expression of IL-2, IL-6, and TNF-α increased following transplantation, whereas HTS therapy attenuated IL production (P < .001). Transplantation increased plasma TNF-α levels and LV TNF-α expression, whereas HTS prevented this up-regulation (P < .001).Conclusions
Recipient HTS pretreatment preserves allograft vasomotor and LV function, and HTS therapy limits CPB-induced injury. HTS may be a novel recipient intervention to prevent graft dysfunction. 相似文献14.
背景 支气管扩张症是呼吸系统常见病、多发病,感染是引起支气管扩张症的最常见原因。人分泌型磷脂酶A2-X(sPLA2-X)在炎性反应中发挥重要作用,并可促进炎性反应的发生、发展,而支气管扩张症合并感染患者血清sPLA2-X表达情况及其与重要炎性指标如降钙素原(PCT)、C反应蛋白(CRP)、诱导型一氧化氮合酶(iNOS)、白介素(IL)-6、IL-17、IL-33是否存在相关性尚未见相关报道。目的 研究支气管扩张症合并感染患者血清sPLA2-X表达情况及其与炎性指标--PCT、CRP、iNOS、IL-6、IL-17、IL-33的相关性,并进一步研究血清sPLA2-X对支气管扩张症合并感染的影响。方法 选取2017年2月-2019年1月在贵州省人民医院呼吸与危重症医学科住院治疗的支气管扩张症合并感染患者47例为病例组,选取同期在贵州省人民医院健康体检中心体检的健康志愿者21例为健康对照组。收集研究对象一般资料,分别检测健康对照组体检当天、观察组治疗前(入院当天)与治疗后(出院前1天)血清sPLA2-X、白细胞计数、PCT、CRP、iNOS、IL-6、IL-17、IL-33。比较两组治疗前后观察指标,分析病例组治疗前血清sPLA2-X与PCT、CRP、iNOS、IL-6、IL-17、IL-33的相关性。结果 病例组治疗前血清sPLA2-X、白细胞计数、PCT、CRP、iNOS、IL-6、IL-17、IL-33均高于健康对照组(P<0.05);病例组治疗后血清sPLA2-X、PCT、CRP、iNOS、IL-17均高于健康对照组(P<0.05);两组治疗后白细胞计数、IL-6、IL-33比较,差异无统计学意义(P>0.05)。病例组治疗后血清sPLA2-X、白细胞计数、PCT、CRP、iNOS、IL-6、IL-17、IL-33均低于本组治疗前(P<0.05)。病例组治疗前血清sPLA2-X与PCT、CRP、iNOS、IL-6、IL-17、IL-33均呈正相关(r=0.526 2、
0.640 1、0.550 7、0.516 8、0.609 9、0.357 4,P值均<0.01)。结论 支气管扩张症合并感染患者血清sPLA2-X升高,且其与PCT、CRP、iNOS、IL-6、IL-7、IL-33呈正相关,表明血清sPLA2-X与支气管扩张症合并感染有重要的关联,血清sPLA2-X可作为评估支气管扩张症合并感染的参考指标。 相似文献
15.
目的:探讨冠心Ⅲ号对缺血性心肌病机体氧化应激及心肌组织纤维化的影响。方法:选取2017年11月至2019年5月广州中医药大学深圳医院收治的ICM患者100例作为研究对象,按照住院号单双分为对照组和观察组,每组50例。对照组常规西医治疗,观察组在对照组基础上加用冠心Ⅲ号治疗,均治疗4周,观察治疗前后NO、SOD、BNP和心肌纤维化指标变化。结果:1)2组患者治疗4周后ET、CRP、BNP、LVEDd、、透明质酸(HA)、Ⅲ型前胶原(PCⅢ)、层粘连蛋白(LN)较治疗前比较均显著降低,NO、SOD、LVEF、△FS、E/A值及SV较治疗前均显著升高,组内比较差异有统计学意义(P<0.01),且观察组显著优于对照组(P<0.01);2)治疗前后2组全血高切、全血中切、全血低切、血浆黏度、红细胞压积、纤维蛋白原差异无统计学意义(P>0.05);3)对照组不良反应率合计12%,观察组为8%,比较差异无统计学意义(P>0.05)。结论:冠心Ⅲ号可通过提高NO、SOD,降低BNP和心肌纤维化,促进血液循环,从而改善心功能,防治ICM。 相似文献
16.
17.
目的:研究外源NO对刺五加种子解除休眠及萌发过程中内源激素及酶的变化规律,为打破刺五加种子休眠和人工栽培提供依据。方法:考察不同浓度(1,5,10,20 mmol·L~(-1))的外源NO供体硝普钠(SNP)处理刺五加种子,而后进行变温层积处理。采用高效液相色谱法检测出在不同层积时间(0,30,50,80,100,130 d)的内源激素赤霉素(GA3),脱落酸(ABA),吲哚乙酸(IAA),吲哚丁酸(IBA)及水杨酸(SA)含量变化。采用酶标仪全程监测体内酶[过氧化氢酶(CAT),超氧化物歧化酶(SOD),过氧化物酶(POD),丙二醛(MDA)]水平的变化。结果:在刺五加种子萌发过程中,GA3,IAA,IBA和SA的含量逐渐增大,脱落酸的含量逐渐减小。POD和MDA水平显著下降,CAT和SOD的酶活力显著上升。外源NO可以提高刺五加种子萌发率,缩短种子萌发时间,20 mmol·L~(-1)SNP促进种子萌发效果最为明显,10 mmol·L~(-1)SNP促进种子萌发效果最弱,呈"V"型变化。结论:SNP促进刺五加种子萌发可能通过提高种子萌发过程中的激素和酶的含量,以提高种子内源NO含量而实现。 相似文献
18.
19.
Jaime L. Clark Carla G. Taylor Peter Zahradka 《Nutrition, metabolism, and cardiovascular diseases : NMCD》2021,31(1):216-226
Background and aimsConsuming pulses (dry beans, dry peas, chickpeas, lentils) over several weeks can improve vascular function and decrease cardiovascular disease risk; however, it is unknown whether pulses can modulate postprandial vascular responses. The objective of this study was to compare different bean varieties (black, navy, pinto, red kidney) and white rice for their acute postprandial effects on vascular and metabolic responses in healthy individuals.Methods and resultsThe study was designed as a single-blinded, randomized crossover trial with a minimum 6 days between consumption of the food articles. Vascular tone (primary endpoint), haemodynamics and serum biochemistry (secondary endpoints) were measured in 8 healthy adults before and at 1, 2, and 6 h after eating ¾ cup of beans or rice. Blood pressure and pulse wave velocity (PWV) were lower at 2 h following red kidney bean and pinto bean consumption compared to rice and navy bean, respectively (p < 0.05). There was greater vasorelaxation 6 h following consumption of darker-coloured beans, as shown by decreased vascular tone: PWV was lower after consuming black bean compared to pinto bean, augmentation pressure was lower after consuming black bean compared to rice and pinto bean, and wave reflection magnitude was lower after consuming red kidney bean and black bean compared to rice, navy bean, and pinto bean (p < 0.05). LDL-cholesterol concentrations were lower 6 h after black bean consumption compared to rice (p < 0.05).ConclusionOverall, red kidney and black beans, the darker-coloured beans, elicited a positive effect on the tensile properties of blood vessels, and this acute response may provide insight for how pulses modify vascular function. 相似文献
20.
Yu-Jyuan Wang Pei-Ying Lin Shu-Ling Hsieh Rajendranath Kirankumar Hsin-Yi Lin Jia-Huei Li Ya-Ting Chen Hao-Ming Wu Shuchen Hsieh 《Materials》2021,14(8)
The purpose of this study was to use agar as a multifunctional encapsulating material to allow drug and ferromagnetism to be jointly delivered in one nanoparticle. We successfully encapsulated both Fe3O4 and doxorubicin (DOX) with agar as the drug carrier to obtain DOX-Fe3O4@agar. The iron oxide nanoparticles encapsulated in the carrier maintained good saturation of magnetization (41.9 emu/g) and had superparamagnetism. The heating capacity test showed that the specific absorption rate (SAR) value was 18.9 ± 0.5 W/g, indicating that the ferromagnetic nanoparticles encapsulated in the gel still maintained good heating capacity. Moreover, the magnetocaloric temperature could reach 43 °C in a short period of five minutes. In addition, DOX-Fe3O4@agar reached a maximum release rate of 85% ± 3% in 56 min under a neutral pH 7.0 to simulate the intestinal environment. We found using fluorescent microscopy that DOX entered HT-29 human colon cancer cells and reduced cell viability by 66%. When hyperthermia was induced with an auxiliary external magnetic field, cancer cells could be further killed, with a viability of only 15.4%. These results show that agar is an efficient multiple-drug carrier, and allows controlled drug release. Thus, this synergic treatment has potential application value for biopharmaceutical carrier materials. 相似文献