树鼩(Tuapaia belangeri chinensis)的动脉

本文在对中国树鼩的动脉系作系统解剖的基础上,记述了树鼩动脉分支的主要特征。同时,还与其他有关种类作了比较研究。结果表明,中国树鼩动脉系的主要特征与树鼩科中的其他种类如笔尾树鼩、普通树鼩和地树鼩等的动脉系极为相似,而与灵长类中的猿猴类有较大差异。     

血清CX3CL1 水平对冠心病的临床意义探讨

目的:探讨冠心病患者血清中趋化因子CX3CL1的表达在冠心病中的临床意义。方法:采用病例-对照的研究方法,依据临床症状收集经冠脉造影显示确诊为冠心病的患者250例,其中临床症状诊断为稳定性心绞痛患者75例,不稳定型心绞痛患者75例,急性心肌梗死患者100例(其中包含ST段抬高型急性心肌梗死和非ST段抬高型急性心肌梗死患者各50例)。同期收集对照组200例,对照组为冠状动脉造影显示为正常。ELISA方法检测上述不同人群血清中趋化因子CX3CL1表达变化,利用流式细胞仪检测上述不同人群血清中CD4~+CD28~-CX3CR1+T细胞表达含量的变化。结果:冠心病患者组血清趋化因子CX3CL1表达明显高于对照组(P0.05);与稳定型冠心病组患者相比较,不稳定型冠心病组和急性心肌梗死组患者血清中趋化因子CX3CL1水平明显高于稳定型冠心病患者组(P0.05);ST段抬高型急性心肌梗死患者血清CX3CL1表达水平高于非ST段抬高型急性心肌梗死患者(P0.05)。不稳定型心绞痛患者冠状动脉介入手术后即刻抽取患者的静脉血,血清中CX3CL1表达含量明显高于冠状动脉介入手术前血清中的表达含量。冠心病患者CD4~+CD28~-CX3CR1+T细胞受体的表达含量明显增高,在急性ST段抬高型心肌梗死患者血清中的表达最高(P0.05)。结论:趋化因子CX3CL1可能参与冠心病动脉粥样硬化不稳定斑块的形成,并且可能成为外周血中预测不稳定型斑块的血清生物学标志物。     

Improved arterial wall model by coculturing vascular endothelial and smooth muscle cells

We have constructed an in vitro arterial wall model by coculturing bovine arterial endothelial cells (ECs) and smooth muscle cells (SMCs). When ECs were seeded directly over SMCs and cocultured in an ordinary culture medium, ECs grew sparsely and did not form a confluent monolayer. Addition of ascorbic acid to the culture medium at concentrations greater than 50 μg/ml increased the production of type IV collagen by the SMCs, and ECs formed a confluent monolayer covering the entire surface of SMCs. Histological studies showed that the thickness of the cell layer composed of ECs and SMCs increased with increasing duration of coculture. This arterial wall model, prepared by our method, may serve as a simple and good in vitro model to study the effects of factors such as biological chemicals and shear stress on cell proliferation and other physiological functions of arterial walls.     

碳酸镧咀嚼片联合依降钙素对血液透析高磷血症患者冠状动脉钙化及血磷水平的影响

摘要 目的：观察碳酸镧咀嚼片联合依降钙素对血液透析高磷血症患者冠状动脉钙化及血磷水平的影响。方法：选取2019年8月~2021年3月我院接收的血液透析高磷血症患者120例,采用双色球法,将患者分为对照组（60例,依降钙素治疗）和观察组（60例,在对照组基础上结合碳酸镧咀嚼片治疗）,对比两组疗效、血磷、血钙、钙磷乘积、全段甲状旁腺激素（iPTH）、成纤维生长因子23（FGF-23）、冠状动脉钙化积分（CACS）,观察两组不良反应发生情况。结果：观察组临床总有效率（91.67%）优于对照组（70.00%）（P<0.05）。两组不良反应发生率组间对比无差异（P>0.05）。观察组治疗结束后血磷、iPTH、血钙、FGF-23、钙磷乘积、CACS低于对照组（P<0.05）。结论：血液透析高磷血症患者采用碳酸镧咀嚼片联合依降钙素治疗,可延缓冠状动脉钙化,有效降低血磷水平,安全有效。     

The use of small angle light scattering in assessing strain induced collagen degradation in arterial tissue ex vivo

Collagen is the predominant load bearing component in many soft tissues including arterial tissue and is therefore critical in determining the mechanical integrity of such tissues. Degradation of collagen fibres is hypothesized to be a strain dependent process whereby the rate of degradation is affected by the magnitude of strain applied to the collagen fibres. The aim of this study is to investigate the ability of small angle light scattering (SALS) imaging to identify strain dependent degradation of collagen fibres in arterial tissue ex vivo, and determine whether a strain induced protection mechanism exists in arterial tissue as observed in pure collagen and other collagenous tissues. SALS was used in combination with histological and second harmonic generation (SHG) analysis to determine the collagen fibre architecture in arterial tissue subjected to strain directed degradation. SALS alignment analysis identified statistically significant differences in fibre alignment depending on the strain magnitude applied to the tissue. These results were also observed using histology and SHG. Our findings suggest a strain protection mechanism may exist for arterial collagen at intermediate strain magnitudes between 0% and 25%. These findings may have implications for the onset and progression of arterial disease where changes in the mechanical environment of arterial tissue may lead to changes in the collagen degradation rate.     

Characterization of arteriovenous identity in the developing neonate mouse retina

The murine retina has become an ideal model to study blood vessel formation. Blood vessels in the retina undergo various processes, including remodeling and differentiation, to form a stereotypical network that consists of precisely patterned arteries and veins. This model presents a powerful tool for understanding many different aspects of angiogenesis including artery and vein (AV) cell fate acquisition and differentiation. However, characterization of AV differentiation has been largely unexplored in the mouse retinal model. In this study, we describe the expression of previously established AV markers and assess arteriovenous acquisition and identity in the murine neonatal retina. Using in situ hybridization and immunofluorescent antibody staining techniques, we analyzed numerous AV differentiation markers such as EphB4-EphrinB2 and members of the Notch pathway. We find that at postnatal day 3 (P3), when blood vessels are beginning to populate the retina, AV identity is not immediately established. However, by P5 expression of many molecular identifiers of arteries and veins become restricted to their respective vessel types. This molecular distinction is more obvious at P7 and remains unchanged through P9. Overall, these studies indicate that, similar to the embryo, acquisition of AV identity occurs in a step-wise process and is largely established by P7 during retina development.     

Multi-input deep learning approach for Cardiovascular Disease diagnosis using Myocardial Perfusion Imaging and clinical data

PurposeAccurate detection and treatment of Coronary Artery Disease is mainly based on invasive Coronary Angiography, which could be avoided provided that a robust, non-invasive detection methodology emerged. Despite the progress of computational systems, this remains a challenging issue. The present research investigates Machine Learning and Deep Learning methods in competing with the medical experts' diagnostic yield. Although the highly accurate detection of Coronary Artery Disease, even from the experts, is presently implausible, developing Artificial Intelligence models to compete with the human eye and expertise is the first step towards a state-of-the-art Computer-Aided Diagnostic system.MethodsA set of 566 patient samples is analysed. The dataset contains Polar Maps derived from scintigraphic Myocardial Perfusion Imaging studies, clinical data, and Coronary Angiography results. The latter is considered as reference standard. For the classification of the medical images, the InceptionV3 Convolutional Neural Network is employed, while, for the categorical and continuous features, Neural Networks and Random Forest classifier are proposed.ResultsThe research suggests that an optimal strategy competing with the medical expert's accuracy involves a hybrid multi-input network composed of InceptionV3 and a Random Forest. This method matches the expert's accuracy, which is 79.15% in the particular dataset.ConclusionImage classification using deep learning methods can cooperate with clinical data classification methods to enhance the robustness of the predicting model, aiming to compete with the medical expert's ability to identify Coronary Artery Disease subjects, from a large scale patient dataset.     

A comparison between the record height-to-stem diameter allometries of Pachycaulis and Leptocaulis species

BACKGROUND AND AIMS: The interspecific allometry of maximum plant height (Hmax) with respect to maximum basal stem diameter (Dmax) has been studied for leptocaulis dicot and conifer tree species. In contrast, virtually nothing is known about the interspecific allometry of pachycaulis species. Here, the interspecific allometries for palms, cacti and cycads are reported and compared with those of leptocaulis dicot and conifer tree species to determine whether pachycauly limits Hmax with respect to Dmax. METHODS: Data for each of a total of 1461 pachycaulis and leptocaulis species were gathered from the primary literature. The scaling exponent and the allometric constant of logHmax vs. logDmax reduced major axis regression curves (and their respective 95 % confidence intervals) were used to compare the four species groups. The stem slenderness ratio (Hmax/Dmax = Rmax) for each species was also computed to compare interspecific trends in trunk shape. KEY RESULTS AND CONCLUSIONS: Each of the four species groups is allometrically unique, i.e. no single 'canonical' maximum plant height to stem diameter allometry exists across all four species groups. Although pachycaulis does not intrinsically limit height, height is nevertheless limited by the size range of basal stem diameter occupied by each species group. Pachycaulis species achieve heights comparable to some leptocaulis species by virtue of very high slenderness ratios attended by an absence or paucity of stem branching. The diversity observed for pachycaulis stem allometries is likely the result of the independent evolutionary origins of this growth habit and the different anatomical strategies used to stiffen stems.     

Effects of altitude on exercise level and heart rate in patients with coronary artery disease and healthy controls

Background. To evaluate the safety and effects of high altitude on exercise level and heart rate in patients with coronary artery disease compared with healthy controls. Methods. Eight patients with a history of an acute myocardial infarction (ejection fraction >5%) with a low-risk score were compared with seven healthy subjects during the Dutch Heart Expedition at the Aconcagua in Argentina in March 2007. All subjects underwent a maximum exercise test with a cycle ergometer at sea level and base camp, after ten days of acclimatisation, at an altitude of 4200 m. Exercise capacity and maximum heart rate were compared between groups and within subjects. Results. There was a significant decrease in maximum heart rate at high altitude compared with sea level in both the patient and the control group (166 vs. 139 beats/min, p<0.001 and 181 vs. 150 beats/min, p<0.001). There was no significant difference in the decrease of the exercise level and maximum heart rate between patients and healthy controls (-31 vs. -30%, p=0.673). Conclusion. Both patients and healthy controls showed a similar decrease in exercise capacity and maximum heart rate at 4200 m compared with sea level, suggesting that patients with a history of coronary artery disease may tolerate stay and exercise at high altitude similarly to healthy controls. (Neth Heart J 2010;18:118-21.)     

Apoptosis during CABG surgery with the use of cardiopulmonary bypass is prominent in ventricular but not in atrial myocardium

Objectives. We aimed to compare the rate of apoptosis after cardiopulmonary bypass (CPB) and cardioplegic arrest during coronary artery bypass grafting (CABG) surgery between atrial and ventricular tissue. Methods. During CABG surgery with CPB and cardioplegic arrest, sequential biopsies were taken from the right atrial appendage and left ventricular anterior wall before CPB and after aortic cross clamp release. Change in number of apoptotic cells and biochemical markers of myocardial ischaemia and renal dysfunction were assessed. Results. CPB was associated with a transient small, but significant increase in CK (1091±374%), CK-MB (128±38%), troponin-T (102±13%) and NT-proBNP (1308±372%) levels (all: p<0.05). A higher number of apoptotic cells as assessed by caspase-3 staining was found in the ventricular biopsies taken after aortic cross clamp release compared with the biopsies taken before CPB (5.3±0.6 vs. 14.0±1.5 cells/microscopic field, p<0.01). The number of apoptotic cells in the atrial appendage was not altered during CPB. Correlation between the duration of aortic cross clamp time and the change in caspase-3 positive cells in the left ventricular wall was of borderline significance (r of 0.58, p=0.08). Similar results were obtained from TUNEL staining for apoptosis. Conclusion. CABG surgery with CPB and cardioplegic arrest is associated with an elevated rate of apoptosis in ventricular but not in atrial myocardial tissue. Ventricular tissue may be more sensitive to detect changes than atrial tissue, and may be more useful to investigate the protective effects of therapeutic intervention. (Neth Heart J 2010;18:236-42.)