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101.
Clinical utility of multi‐detector cardiac computed tomography in structural heart interventions
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Bo Xu Robert Gooley Sujith K Seneviratne Arthur Nasis 《Journal of Medical Imaging and Radiation Oncology》2016,60(3):299-305
In recent years, there have been major advances in structural interventional cardiology, which have revolutionized the practice of cardiology. Appropriate selection and follow‐up of patients undergoing these structural heart interventions is vital. Multi‐detector computed tomography (MDCT) has emerged as a key imaging modality in the peri‐procedural assessment of patients undergoing multiple structural cardiac interventions. The purpose of this review is to provide an evidence‐based clinical update on the roles of MDCT in both established and evolving structural heart interventions, including transcatheter aortic valve replacement (TAVR) and transcatheter mitral valve implantation (TMVI). The utility of MDCT in the peri‐procedural assessment of patients undergoing pulmonary vein isolation (PVI) for atrial fibrillation, cardiac resynchronization therapy (CRT) and left atrial appendage (LAA) closure will also be reviewed. 相似文献
102.
桑白皮丙酮提取物舒张血管作用机制研究 总被引:6,自引:0,他引:6
目的研究桑白皮丙酮提取物的舒张血管作用及作用机制.方法用去甲肾上腺素致豚鼠肠系膜微血管收缩,研究其整体的舒张血管作用;在添加或不添加优降糖或普萘洛尔,或去血管内皮情况下,观察其对离体大鼠胸主动脉环的作用;硝酸还原酶法测定给予药物后大鼠血浆和血管的NO以及血管NOS、cNOS、iNOS含量的变化.结果桑白皮丙酮提取物有抑制去甲肾上腺素收缩豚鼠肠系膜微血管的作用,抑制苯肾上腺素(10μmol/L)收缩离体大鼠胸主动脉环的作用,预加优降糖(1μmol/L)或普萘洛尔((3μmol/L)后仍然有松弛作用;大鼠胸主动脉环去内皮后药物无松弛作用,反而起收缩作用;显著升高血管的NO和NOS、cNOS的含量,对大鼠血浆的NO和血管iNOS的含量影响不大.结论桑白皮丙酮提取物的舒张血管作用机制可能与血管释放NO和促进cNOS、NOS合成有关. 相似文献
103.
Hui Wang Jurgen Seidel Christopher Bartos Russell Byrum Philip J. Sayre Kurt Cooper Yu Cong Dong-Yun Kim Claudia Calcagno Jens H. Kuhn Anya Crane Jiro Wada Reed F. Johnson Dima A. Hammoud Ji Hyun Lee 《Viruses》2022,14(11)
Positron emission tomography (PET) is becoming an important tool for the investigation of emerging infectious diseases in animal models. Usually, PET imaging is performed after intravenous (IV) radiotracer administration. However, IV injections are difficult to perform in some small animals, such as golden hamsters. This challenge is particularly evident in longitudinal imaging studies, and even more so in maximum containment settings used to study high-consequence pathogens. We propose the use of intramuscular (IM) administration of 2-deoxy-2[18F]fluoro-D-glucose ([18F]F-FDG) for PET imaging of hamsters in a biosafety level 4 (BSL-4) laboratory setting. After [18F]F-FDG administration via IM or IV (through surgically implanted vascular access ports), eight hamsters underwent static or dynamic PET scans. Time–activity curves (TACs) and standardized uptake values (SUVs) in major regions of interest (ROIs) were used to compare the two injection routes. Immediately after injection, TACs differed between the two routes. At 60 min post-injection, [18F]F-FDG activity for both routes reached a plateau in most ROIs except the brain, with higher accumulation in the liver, lungs, brain, and nasal cavities observed in the IM group. IM delivery of [18F]F-FDG is an easy, safe, and reliable alternative for longitudinal PET imaging of hamsters in a BSL-4 laboratory setting. 相似文献
104.
Yu Togashi Daisuke Miyashita Takahiro Tsuno Ryota Inoue Tomoko Okuyama Mayu Kyohara Kuniyuki Nishiyama Masanori Arai Kenta Kanematsu Soichiro Kanataki Yasuo Terauchi Jun Shirakawa 《Journal of diabetes investigation.》2022,13(11):1861
Aims/IntroductionThis study aimed to clarify the nature of the relationship between the abdominal aortic calcification (AAC) grade and the presence of cardiovascular diseases, and determine factors related to AAC grade in people with type 2 diabetes mellitus.Materials and MethodsThis retrospective cross‐sectional study enrolled 264 inpatients with type 2 diabetes mellitus. The AAC score and length were measured using the lateral abdominal radiographs. Logistic regression models were used to assess the associations between AAC scores/lengths and the presence of coronary artery disease (CAD), cerebral infarction (CI) and peripheral artery disease (PAD). The correlation between AAC scores/lengths and other clinical factors were evaluated using linear regression models.ResultsThe AAC score was significantly correlated with prevalent CAD and CI independent of age and smoking, but not with the prevalence of PAD. AAC length was not significantly correlated with the presence of CAD, CI or PAD; however, the sample size was insufficient to conclude, probably due to low prevalence. Both the AAC score and length were correlated inversely with body mass index (BMI) and, with the Fibrosis‐4 (Fib‐4) index >2.67; these correlations were significant after adjusting for cardiovascular risk factors and BMI, although AAC was not associated with ultrasonography‐diagnosed fatty liver. There was a significant interaction between BMI and Fib‐4 index; lower BMI and Fib‐4 index >2.67 showed a synergistic association with high AAC grade.ConclusionsAAC score is associated with CAD and CI morbidity in participants with type 2 diabetes mellitus. Low BMI and Fib‐4 index >2.67 can be valuable indicators of AAC in people with type 2 diabetes mellitus. 相似文献
105.
Jianrong Li Jun Zheng Xiufeng Jin Kai Zhu Xiaolong Wang Hongjia Zhang 《Journal of thoracic disease》2022,14(9):3552
BackgroundThe definite pathogenesis of lung injury complicated by type A aortic dissection (TAAD) remains unclear. In this paper, we investigated the relationship between intestinal injury, lung injury, and systemic inflammatory responses, with the aim of exploring the mechanism underlying intestinal injury and its impact on systemic inflammatory responses and lung injury in patients with TAAD.MethodsPatients with TAAD (n=36) and those with aortic root aneurysm (ARA) (n=30) were compared. TAAD patients were younger and had higher creatinine (Cr) than ARA patients. White blood cell (WBC) count, neutrophil count, neutrophil percentage, interleukin (IL)-6, IL-8, tumor necrosis factor α (TNF-α), C-reactive protein (CRP), histamine (HIS) levels, PaO2-FiO2 ratio, diamine oxidase (DAO), intestinal fatty acid binding protein (iFABP), and peptidoglycan (PGN) were measured using the same laboratory methods between the two groups.ResultsIncreased WBC [(9.70±4.05)×109/L vs. (5.88±1.2)×109/L, P<0.001], neutrophil [(7.65±4.27)×109/L vs. (3.40±0.97)×109/L, P<0.001], neutrophil percentage [(74.73±13.42)% vs. (57.67±9.45)%, P<0.001], IL-6 (37.48±4.87 vs. 20.90±0.92 pg/mL, P<0.001), IL-8 (97.15±9.11 vs. 69.46±3.17 pg/mL, P<0.001), TNF-α (71.32±10.35 vs. 33.90±2.27 pg/mL, P<0.001), CRP (10.67±1.62 vs. 4.43±0.26 µg/mL, P<0.001), HIS (13.29±1.88 vs. 7.63±0.58 ng/mL, P<0.001), DAO (24.94±4.72 vs. 10.92±2.44 U/L, P<0.001), iFABP (879.01±190.12 vs. 206.35±42.20 pg/mL, P<0.001), and PGN (31.10±5.51 vs. 12.52±2.20 ng/mL, P<0.001) and decreased PaO2-FiO2 ratio (365.35±146.47 vs. 447.86±70.80 mmHg, P=0.01) were detected in TAAD group relative to ARA group. In TAAD group, positive correlations were detected between DAO and inflammatory cytokines [IL-6 (r=0.56, P<0.001), IL-8 (r=0.61, P<0.001), TNF-α (r=0.71, P<0.001), and CRP (r=0.68, P<0.001)], between iFABP and inflammatory cytokines [IL-6 (r=0.72, P<0.001), IL-8 (r=0.71, P<0.001), TNF-α (r=0.90, P<0.001), and CRP (r=0.89, P<0.001)], between DAO and PGN (r=0.52, P<0.001), between iFABP and PGN (r=0.74, P<0.001), between PGN and inflammatory cytokines [IL-6 (r=0.85, P<0.001), IL-8 (r=0.44, P<0.001), TNF-α (r=0.61, P<0.001), and CRP (r=0.73, P<0.001)]. In acute TAAD subgroup, PGN and PaO2-FiO2 ratio were negatively correlated (r=−0.50, P=0.036).ConclusionsSystemic inflammatory responses in TAAD patients may lead to lung and intestine injury, and the latter may be involved in the development of systemic inflammatory responses and lung injury in these patients. 相似文献
106.
Arun Maharaj Stephen M. Fischer Katherine N. Dillon Yejin Kang Mauricio A. Martinez Arturo Figueroa 《Nutrients》2022,14(20)
Aging and menopause are associated with decreased nitric oxide bioavailability due to reduced L-arginine (L-ARG) levels contributing to endothelial dysfunction (ED). ED precedes arterial stiffness and hypertension development, a major risk factor for cardiovascular disease. This study investigated the effects of L-citrulline (L-CIT) on endothelial function, aortic stiffness, and resting brachial and aortic blood pressures (BP) in hypertensive postmenopausal women. Twenty-five postmenopausal women were randomized to 4 weeks of L-CIT (10 g) or placebo (PL). Serum L-ARG, brachial artery flow-mediated dilation (FMD), aortic stiffness (carotid-femoral pulse wave velocity, cfPWV), and resting brachial and aortic BP were assessed at 0 and 4 weeks. L-CIT supplementation increased L-ARG levels (Δ13 ± 2 vs. Δ−2 ± 2 µmol/L, p < 0.01) and FMD (Δ1.4 ± 2.0% vs. Δ−0.5 ± 1.7%, p = 0.03) compared to PL. Resting aortic diastolic BP (Δ−2 ± 4 vs. Δ2 ± 5 mmHg, p = 0.01) and mean arterial pressure (Δ−2 ± 4 vs. Δ2 ± 6 mmHg, p = 0.04) were significantly decreased after 4 weeks of L-CIT compared to PL. Although not statistically significant (p = 0.07), cfPWV decreased after L-CIT supplementation by ~0.66 m/s. These findings suggest that L-CIT supplementation improves endothelial function and aortic BP via increased L-ARG availability. 相似文献
107.
Kefeng Zhang Xudong Pan Jun Zheng Yongmin Liu Lizhong Sun 《Journal of clinical laboratory analysis》2022,36(9)
BackgroundThe metabolic profile of human aortic tissues is of great importance. Among the analytical platforms utilized in metabolomics, LC‐MS provides broad metabolome coverage. The non‐targeted metabolomics can comprehensively detect the entire metabolome of an organism and find the metabolic characteristics that have significant changes in the experimental group and the control group and elucidate the metabolic pathway concerning the recognized metabolites. Employing non‐targeted metabolomics is helpful to develop biomarkers for disease diagnosis and disease pathology research; for instance, Aortic aneurysm (AA) and Aortic dissection (AD).AimThis study sought to describe the non‐targeted analysis of 18 aortic tissue samples, comparing between AA and AD.Material & MethodsOur experimental flow included dividing the samples into (AA, nine samples) and (AD, nine samples), SCIEX quadrupole timeofflight tandem mass spectrometer (TripleTOF) 6600+ mass spectrometer data refinement, MetDNA database analysis, and pathway analysis. We performed an initial validation by setting quality control parameters to evaluate the stability of the analysis system during the computer operation. We then used the repeatability of the control samples to examine the stability of the instrument during the entire analysis process to ensure the reliability of the results.ResultsOur study found 138 novel metabolites involved in galactose metabolism.Discussion138 novel metabolites found in this study will be further studied in the future.ConclusionOur study found 138 novel metabolites between AA and AD, which will provide viable clinical data for future studies aimed to implement galactose markers in aortic tissue analysis. 相似文献
108.
目的 探讨支架象鼻内球囊阻断联合浅低温停循环、双侧脑灌注技术与传统孙氏手术在Stanford A型主动脉夹层术中的对比.方法 回顾性分析2019年1月至2020年12月在我院接受孙氏手术治疗的81例急性Stanford A型主动脉夹层患者资料.根据术中操作方式分为传统组和改良组,传统组按照传统孙氏手术方式处理主动脉弓部... 相似文献
109.
Shujuan Cui Yimeng Liu Jiachen Zhao Xiaomin Peng Guilan Lu Weixian Shi Yang Pan Daitao Zhang Peng Yang Quanyi Wang 《Viruses》2022,14(7)
The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has lasted for two years and caused millions of infections and deaths in humans. Although the origin of SARS-CoV-2 infection in humans remains unknown, infection in animals has been frequently reported in varieties of animals all over the world. Both experimental and natural infections of SARS-CoV-2 in different animal species provide useful information on viral host range and pathogenicity. As the pandemic continues to evolve, SARS-CoV-2 infection in animals will be expanding. In this review, we summarized SARS-CoV-2 testing and infection in animals as well as SARS-CoV-2 strains and transmission in animals. Current data showed that at least 18 different animal species tested positive for SARS-CoV-2. These 18 animal species belong to pet, captive, farmed, and wild animals. Fifteen of the eighteen animal species were known to be positive for the Delta variant and ten animal species were infected with two different types of variants. Human-to-animal, animal-to-animal, and animal-to-human transmission events were suggested in different outbreaks involved in animal infection with SARS-CoV-2. Continued testing, immunization, and surveillance are warranted. 相似文献
110.
目的 对2019—2021年天津市人民医院贝伐珠单抗的临床应用情况进行评价,以期促进贝伐珠单抗超说明书用药的管理及其临床合理应用。方法 回顾性分析天津市人民医院2019年1月—2021年12月使用贝伐珠单抗患者的用药信息,根据说明书及指南评价其应用的合理性。结果 共收集1 313例患者(6 134次医嘱),通过适应症、治疗方案、用法用量3个方面评价应用合理性。结果显示,存在适应症不适宜情况占比0.07%,用法用量不适宜情况占比4.77%,其中包括给药浓度不适宜(1.21%)、给药途径不适宜(0.23%)、与手术间隔时间不适宜(3.33%)。结论 天津市人民医院贝伐珠单抗的临床应用基本符合国内外说明书及指南要求,但也存在一定的超说明书用药情况。医院及临床药师应持续规范抗肿瘤药物超说明书使用的管理,促进抗肿瘤药物的合理应用。 相似文献