Preparation of vascular endothelial cell hypoxia/reoxygenation model / 国际外科学杂志

The vascular endothelial cells (VECs) hypoxia/reoxygenation(H/R) model is a classic cell model that simulates vascular endothelial ischemia/reperfusion (I/R) injury and related diseases. It has the advantages of convenient operation, intuitive image, and good stability, and can accurately reflect pathological changes at the cellular level of diseases. It is widely used in the study of molecular mechanisms of drugs and diseases.There are many similarities in the mechanism and formation between the H/R model and the I/R injury model, but the I/R model is more complex. Therefore, in recent years, many scholars have used the H/R model to simulate the I/R model for experimental research, and believe that the H/R model is also an ideal model for studying I/R. By implementing intervention measures on the established H/R model of VECs, the potential effects of the intervention measures in clinical practice can be verified, which has guiding significance for how to prevent, treat, and how to exacerbate I/R injury in clinical practice. This article introduces the different methods used by scholars in recent years, such as medium deoxygenation and mixed gas culture method, to construct H/R models using VECs cultured in vitro to simulate I/R models. The differences in methods used and the subtle differences between the same methods are also discussed. At the same time, due to the relatively single method of constructing H/R models at present, how to find new, more efficient and affordable methods based on scientific and reasonable experiments has also become a focus of attention.

Diferencias entre los modelos de riesgo Framingham y DAD en la evaluación del riesgo cardiovascular en pacientes con VIH bajo terapia antirretroviral: experiencia en una población del caribe colombiano / Differences between the Framingham and D:A:D risk models for cardiovascular risk assessment in HIV-positive patients on antiretroviral therapy: an experience in a Colombian Caribbean population

RESUMEN Objetivo: Evaluar el riesgo de enfermedad cardiovascular a cinco y a diez años en pacientes con infección por VIH en terapia antirretroviral, por medio de las escalas Framingham y Data collection on Adverse Effects of Anti-HIV Drugs Study. Materiales y métodos: Estudio observacional de corte transversal y prospectivo. Se incluyeron pacientes con infección por el VIH en tratamiento antirretroviral de un centro de referencia para pacientes con VIH, entre el 1 de enero y el 30 de abril de 2019. Se realizó evaluación del riesgo cardiovascular a cinco y a diez años a través de los modelos de predicción de Framingham y la escala Data collection on Adverse Effects of Anti-HIV Drugs Study (DAD), y una comparación entre ellos a través de modelos estadísticos. Resultados: Se incluyeron 159 pacientes, con un promedio de edad de 48,90 años ± 9,90. La media de valoración del riesgo cardiovascular por escala de Framingham a 5 años fue de 2,70 % ± 2,80; Framingham a 10 años fue 6,10 % ± 5,70; DAD a 5 años, 3,50 % ± 4,10; DAD a 10 años, de 6,90 % ± 7,70; y el riesgo escala de Framingham a 10 años recalculado para Colombia (multiplicado por 0,75) fue de 4,50 ± 4,20. A través de un modelo de regresión logística, se determinó que la puntuación con mayor número de variables significativamente relacionadas con el resultado de riesgo cardiovascular alto es el modelo DAD a 10 años. Conclusiones: El estudio evidenció una diferencia significativa, con mayor riesgo estimado de enfermedad cardiovascular al utilizar el modelo DAD en comparación con el Framingham, tanto para la estimación a cinco años como a diez.

ABSTRACT Objective: To assess the five- and ten-year cardiovascular disease risk in HIV-positive patients on antiretroviral therapy, using the Framingham risk score and the Data collection on adverse effects of anti-HIV drugs (D:A:D) study. Materials and methods: An observational prospective cross-sectional study. HIV-positive patients on antiretroviral treatment from a referral center for HIV patients were included in the study between January 1 and April 30, 2019. A five- and ten-year cardiovascular risk assessment was performed using the Framingham risk score and the D:A:D study. Additionally, both risk models were compared through statistical models. Results: The study population consisted of 159 patients with a mean age of 48.90 years ± 9.90. The mean cardiovascular risk according to the five-year Framingham risk score was 2.70 % ± 2.80, the ten-year Framingham risk score was 6.10 % ± 5.70, the five-year D:A:D study was 3.50 % ± 4.10, the ten-year D:A:D study was 6.90 % ± 7.70, and the ten-year Framingham risk score recalculated for Colombia (multiplied by 0.75) was 4.50 % ± 4.20. Using a logistic regression model, it was determined that the ten-year D:A:D study provided the greatest number of variables significantly related to a high cardiovascular risk. Conclusions: The study showed a significant difference between the risk models. Both the five- and ten-year D:A:D study provided a better cardiovascular disease risk estimation than the five- and ten-year Framingham model.

Clinical and pharmacological application of multiscale multiphysics heart simulator, UT-Heart

A heart simulator, UT-Heart, is a finite element model of the human heart that can reproduce all the fundamental activities of the working heart, including propagation of excitation, contraction, and relaxation and generation of blood pressure and blood flow, based on the molecular aspects of the cardiac electrophysiology and excitation-contraction coupling. In this paper, we present a brief review of the practical use of UT-Heart. As an example, we focus on its application for predicting the effect of cardiac resynchronization therapy (CRT) and evaluating the proarrhythmic risk of drugs. Patient-specific, multiscale heart simulation successfully predicted the response to CRT by reproducing the complex pathophysiology of the heart. A proarrhythmic risk assessment system combining in vitro channel assays and in silico simulation of cardiac electrophysiology using UT-Heart successfully predicted druginduced arrhythmogenic risk. The assessment system was found to be reliable and efficient. We also developed a comprehensive hazard map on the various combinations of ion channel inhibitors. This in silico electrocardiogram database (now freely available at http://ut-heart.com/) can facilitate proarrhythmic risk assessment without the need to perform computationally expensive heart simulation. Based on these results, we conclude that the heart simulator, UT-Heart, could be a useful tool in clinical medicine and drug discovery.

Use of 3d printing in preoperative planning and training for aortic endovascular repair and aortic valve disease

Abstract Introduction: Three-dimensional (3D) printing has become an affordable tool for assisting heart surgeons in the aorta endovascular field, both in surgical planning, education and training of residents and students. This technique permits the construction of physical prototypes from conventional medical images by converting the anatomical information into computer aided design (CAD) files. Objective: To present the 3D printing feature on developing prototypes leading to improved aortic endovascular surgical planning, as well as transcatheter aortic valve implantation, and mainly enabling training of the surgical procedure to be performed on patient's specific condition. Methods: Six 3D printed real scale prototypes were built representing different aortic diseases, taken from real patients, to simulate the correction of the disease with endoprosthesis deployment. Results: In the hybrid room, the 3D prototypes were examined under fluoroscopy, making it possible to obtain images that clearly delimited the walls of the aorta and its details. The endovascular simulation was then able to be performed, by correctly positioning the endoprosthesis, followed by its deployment. Conclusion: The 3D printing allowed the construction of aortic diseases realistic prototypes, offering a 3D view from the two-dimensional image of computed tomography (CT) angiography, allowing better surgical planning and surgeon training in the specific case beforehand.

Experimental validation of a cardiac simulator for in vitro evaluation of prosthetic heart valves

Abstract Objective: This work describes the experimental validation of a cardiac simulator for three heart rates (60, 80 and 100 beats per minute), under physiological conditions, as a suitable environment for prosthetic heart valves testing in the mitral or aortic position. Methods: In the experiment, an aortic bileaflet mechanical valve and a mitral bioprosthesis were employed in the left ventricular model. A test fluid of 47.6% by volume of glycerin solution in water at 36.5ºC was used as blood analogue fluid. A supervisory control and data acquisition system implemented previously in LabVIEW was applied to induce the ventricular operation and to acquire the ventricular signals. The parameters of the left ventricular model operation were based on in vivo and in vitro data. The waves of ventricular and systemic pressures, aortic flow, stroke volume, among others, were acquired while manual adjustments in the arterial impedance model were also established. Results: The acquired waves showed good results concerning some in vivo data and requirements from the ISO 5840 standard. Conclusion: The experimental validation was performed, allowing, in future studies, characterizing the hydrodynamic performance of prosthetic heart valves.

Morphological description of great cardiac vein in pigs compared to human hearts / Descrição morfológica da grande veia cardíaca em suínos em comparação com corações humanos

Introduction: In spite of its importance as an experimental model, the information on the great cardiac vein in pigs is sparse. Objective: To determine the morphologic characteristics of the great cardiac vein and its tributaries in pigs. Methods: 120 hearts extracted from pigs destined to the slaughterhouse with stunning method were studied. This descriptive cross-over study evaluated continuous variables with T test and discrete variables with Pearson χ square test. A level of significance P<0.05 was used. The great cardiac vein and its tributaries were perfused with polyester resin (85% Palatal and 15% Styrene) and then subjected to potassium hydroxide infusion to release the subepicardial fat. Calibers were measured, and trajectories and relations with adjacent arterial structures were evaluated. Results: The origin of the great cardiac vein was observed at the heart apex in 91 (76%) hearts. The arterio-venous trigone was present in 117 (97.5%) specimens, corresponding to the open expression in its lower segment and to the closed expression in the upper segment in the majority of the cases (65%). The caliber of the great cardiac vein at the upper segment of the paraconal interventricular sulcus was 3.73±0.79 mm. An anastomosis between the great cardiac vein and the middle cardiac vein was found in 59 (49%) specimens. Conclusion: The morphological and biometric characteristics of the great cardiac vein and its tributaries had not been reported in prior studies, and due to their similitude with those of the human heart, allows us to propose the pig model for procedural and hemodynamic applications. .

Introdução: Apesar de sua importância como um modelo experimental, a informação sobre a grande veia cardíaca em suínos é esparsa. Objetivo: Determinar as características morfológicas da grande veia cardíaca e suas tributárias em suínos. Métodos: Foram estudados 120 corações extraídos de suínos destinados para o matadouro com método de atordoamento. Este estudo descritivo cross-over avaliou variáveis contínuas com teste T e variáveis discretas com teste χ quadrado de Pearson. O nível de significância P<0,05 foi usado. A grande veia cardíaca e suas tributárias foram perfundidas com resina de poliéster (85% palatal e estireno de 15%) e, em seguida, submetidas à infusão de hidróxido de potássio para remover a gordura subepicardal. Os calibres foram medidos e trajetórias e relações com estruturas arteriais adjacentes foram avaliadas. Resultados: A origem da grande veia cardíaca foi observada no ápice do coração em 91 (76%) espécimes. O trígono arteriovenoso estava presente em 117 (97,5%) espécimes, correspondente à expressão aberta no seu segmento inferior e para a expressão fechada no segmento superior na maioria dos casos (65%). O calibre da grande veia cardíaca no segmento superior do sulco interventricular paraconal foi de 3,73±0,79 mm. Uma anastomose entre a grande veia cardíaca e da veia cardíaca média foi encontrada em 59 (49%) espécimes. Conclusão: As características morfológicas e biométricas da grande veia cardíaca e suas tributárias não haviam sido relatadas em estudos anteriores e, devido à sua semelhança com as do coração humano, nos permite propor o modelo porcino para procedimentos e aplicações hemodinâmicas. .

Comparison of two surgical techniques for creating an acute myocardial infarct in rats / Comparação de duas técnicas cirúrgicas para criar um infarto agudo do miocárdio em ratos

Objective: To perform a comparative assessment of two surgical techniques that are used creating an acute myocardial infarc by occluding the left anterior descending coronary artery in order to generate rats with a left ventricular ejection fraction of less than 40%. Methods: The study was completely randomized and comprised 89 halothane-anaesthetised rats, which were divided into three groups. The control group (SHAM) comprised fourteen rats, whose left anterior descending coronary artery was not occluded. Group 1 (G1): comprised by 35 endotracheally intubated and mechanically ventilated rats, whose left anterior descending coronary artery was occluded. Group 2 (G2): comprised 40 rats being manually ventilated using a nasal respirator whose left anterior descending coronary artery was occluded. Other differences between the two techniques include the method of performing the thoracotomy and removing the pericardium in order to expose the heart, and the use of different methods and suture types for closing the thorax. Seven days after surgery, the cardiac function of all surviving rats was determined by echocardiography. Results: No rats SHAM group had progressed to death or had left ventricular ejection fraction less than 40%. Nine of the 16 surviving G1 rats (56.3%) and six of the 20 surviving G2 rats (30%) had a left ventricular ejection fraction of less than 40%. Conclusion: The results indicate a tendency of the technique used in G1 to be better than in G2. This improvement is probably due to the greater duration of the open thorax, which reduces the pressure over time from the surgeon, allowing occlusion of left anterior descending coronary artery with higher accuracy. .

Objetivo: Realizar uma avaliação comparativa de duas técnicas cirúrgicas que são usadas para criar um infarto agudo do miocárdio pela oclusão da artéria coronária descendente anterior esquerda, a fim de gerar ratos com uma fração de ejeção ventricular esquerda inferior a 40%. Métodos: O estudo foi completamente randomizado e composto por 89 ratos anestesiados com halotano, que foram divididos dentro de três grupos. O grupo controle (SHAM) composto por 14 ratos, cuja artéria coronária descendente anterior esquerda não foi ocluída. Grupo 1 (G1): composto por 35 ratos intubados endotraquealmente e ventilados mecanicamente, cuja artéria coronária descendente anterior esquerda foi ocluída. Grupo 2 (G2): constituído por 40 ratos sendo ventilados manualmente utilizando um respirador nasal, cuja artéria coronária descendente anterior esquerda foi ocluída. Outras diferenças entre as duas técnicas incluem o método de realizar a toracotomia e remover o pericárdio, a fim de expor o coração, e o uso de diferentes métodos e tipos de sutura para fechar o tórax. Sete dias após a cirurgia, a função cardíaca de todos os ratos sobreviventes foi determinada por ecocardiografia. Resultados: Nenhum rato do grupo SHAM foi a óbito ou teve fração de ejeção ventricular esquerda menor que 40%. Nove dos 16 ratos sobreviventes do G1 (56,3%) e seis dos 20 ratos sobreviventes do G2 (30%) tiveram uma fração de ejeção ventricular esquerda inferior a 40%. Conclusão: Os resultados indicam uma tendência da técnica utilizada no G1 ser melhor do que a do G2. Esta melhora deve-se provavelmente à maior duração do tórax aberto, o que reduz a pressão de tempo sobre o cirurgião, permitindo uma oclusão da artéria coronária descendente anterior esquerda com maior acurácia. .

Cardiovascular risk in middle-aged breast cancer survivors: a comparison between two risk models / Risco cardiovascular em mulheres de meia-idade com câncer de mama: uma comparação entre dois modelos de risco

PURPOSE: It was to assess the risk of cardiovascular disease (CVD) in breast cancer survivors (BCS). METHODS: This cross-sectional study analyzed 67 BCS, aged 45 -65 years, who underwent complete oncological treatment, but had not received hormone therapy, tamoxifen or aromatase inhibitors during the previous 6 months. Lipid profile and CVD risk were evaluated, the latter using the Framingham and Systematic COronary Risk Evaluation (SCORE) models. The agreement between cardiovascular risk models was analyzed by calculating a kappa coefficient and its 95% confidence interval (CI). RESULTS: Mean subject age was 53.2±6.0 years, with rates of obesity, hypertension, and dyslipidemia of 25, 34 and 90%, respectively. The most frequent lipid abnormalities were high total cholesterol (70%), high LDL-C (51%) and high non-HDL-C (48%) concentrations. Based on the Framingham score, 22% of the participants had a high risk for coronary artery disease. According to the SCORE model, 100 and 93% of the participants were at low risk for fatal CVD in populations at low and high risk, respectively, for CVD. The agreement between the Framingham and SCORE risk models was poor (kappa: 0.1; 95%CI 0.01 -0.2) for populations at high risk for CVD. CONCLUSIONS: These findings indicate the need to include lipid profile and CVD risk assessment in the follow-up of BCS, focusing on adequate control of serum lipid concentrations. .

OBJETIVO: Avaliar o risco de doença cardiovascular (DCV) em mulheres com câncer de mama. MÉTODOS: Foi conduzido estudo de corte transversal, com 67 mulheres com câncer de mama, entre 45 e 65 anos, tratamento oncológico completo, não usuárias de terapia hormonal, tamoxifeno ou inibidores da aromatase nos últimos 6 meses. Foram avaliados o perfil lipídico e o risco de DCV. Para avaliar o risco de DCV, foram utilizados os modelos Framingham e Systematic COronary Risk Evaluation (SCORE). Para investigar a concordância entre os modelos de risco cardiovascular, foi calculado o coeficiente kappa com seu respectivo intervalo de confiança (IC) de 95%. RESULTADOS: A média de idade das participantes foi de 53,2±6,0 anos. A prevalência de obesidade, hipertensão e dislipidemia foi 25, 34 e 90%, respectivamente. A prevalência de dislipidemia foi 90%. As anormalidades mais comuns do perfil lipídico foram: alto colesterol total (70%), alto LDL-C (51%) e alto não HDL-C (48%). Baseado no escore de Framingham, 22% das mulheres com câncer de mama apresentaram alto risco de doença arterial coronariana. De acordo com o modelo SCORE, 100 e 93% das participantes apresentaram baixo risco de DCV fatal, considerando populações de baixo e alto risco de DCV, respectivamente. A concordância entre os modelos de Framingham e SCORE foi ruim (kappa: 0,1; IC95% 0,01 -0,2), considerando populações de alto risco de DCV. CONCLUSÕES: Esses dados indicam a necessidade de incluir a avaliação do perfil lipídico e do risco de DCV na rotina de seguimento de mulheres com câncer de mama, sendo observadoo adequado controle dos níveis séricos de lipídios. .

Digital three-dimensional model reconstruction of the cardiac cavity / 中国组织工程研究

BACKGROUND:Digital three-dimensional model which can reflect the fine structure of the chambers inside heart not only enhances the understanding of cardiac physiology, but also provides basic medical data for the study of cardiac electrophysiology simulation and endocardial electrophysiological mapping navigation. OBJECTIVE:To construct the digital three-dimensional model of cardiac cavity from sectional data and in conformity with the actual anatomical structure. METHODS:Image segmentation was accomplished in MATLAB environment. Firstly, registration of human cardiac cavity slice dataset was realized. Secondly, classifying each composition was achieved by clustering method according to color characteristics of the image. Then, both cardiac cavity and related connected region was distinguished by region growing method. At last, the processed image was reconstructed through dedicated medical processing software into three-dimensional model of the cardiac cavity. RESULTS AND CONCLUSION:The proposed method could reconstruct quite exquisite three-dimensional model of the cardiac cavity. In models, left and right atrial and ventricular structure was clear. Aorta and superior vena cava were visible. Three tricuspid and mitral valve were also observed. Results indicated that reconstructed model can reflect the anatomical characteristics of cardiac cavity accurately, and provide basic medical data for the study on electrophysiological simulation and endocardial electric mapping.

Ten-year risk of ischemic cardiovascular diseases in middle-aged adults in Henan province / 中华健康管理学杂志

Objective To evaluate 10-year risk of ischemic cardiovascular diseases (ICVD) in middle-aged adults in Henan province to provide evidence for improved health status. Methods The 10- year risk of ICVD in 12 064 middle-aged adults was evaluated by using simplified risk estimation model. Results About 96. 35% of male and 98. 29% of female had a probability of < 10% to develop ICVD over 10 years; 3.65% of male and 1.71% of female had a probability of ≥ 10% to develop ICVD over 10 years; and 0.68% of male and 0.23% of female had a probability of≥20% to develop ICVD over 10 years. The prevalence of risk factors for ICVD in two absolute risk groups ( ≥10% vs < 10% ) was significantly different. Conclusions The risk of ICVD in the middle-aged residents of Henan province may be similar to that in the middle-aged Chinese adults. The risk assessment for ICVD could be used for high- risk populations.

Establishment of Animal Model of Coronary Heart Disease with the Blending of Phlegm and Blood Stasis / 广州中医药大学学报

【Objective】To explore a method for the establishment of animal model of coronary heart disease(CHD) with the blending of phlegm and blood stasis.【Methods】Methods of TCM-WM combination(traditional Chinese medicine integrated with western medicine) and disease-syndrome combination were used to establish a model.The model was evaluated by the changes of symptoms,signs and laboratory indexes and by the effect of blood-stasis-removing and phlegm-resolving herbs on the model.Sixty Wistar rats were randomized into normal group,model group,low-dose herbal medicine group and high-dose herbal medicine group.The normal group was fed with routine forage and normal saline,and the other three groups with high-fat forage and fat milk(10mL?kg~(-1)?d~(-1)).Low-and high-dose herbal medicine groups were given Xuefu Zhuyu Decoction combined with Gualou Xiebai Banxia Decoction in the dosages of 12 and 24 10g?kg~(-1)?d~(-1)respectively by gastric gavage,and the model group given the same volume of normal saline for 7 consecutive weeks.Coronary artery ligation was performed in the 35~(th) day.The changes of electrocardiogram(ECG) were observed before and after the modeling,and blood lipid,myocardial enzymes and hemorrheological parameters were determined.The heart weight was examined to calculate heart index.【Results】ECG in the model group indicated severe myocardial ischemia,which may be relieved by herbal medicine.Serum contents of cholesteril,tryglyceride and creatine kinase(CK),whole blood viscosity,hematocrit and heart index were obviously increased in the model group,while the above indexes decreased to different degrees in herbal medicine groups (P

An experimental study on the embolus-capturing efficiency of a new-designed retrievable artery filter / 中华放射学杂志

Objective To develop a physical in vitro model of the human carotid artery(CA) and analyze the factors that influence the embolus-capturing efficiency of the retrievable artery filters. Methods The flow model closely simulated the physiological parameters of the human carotid artery. The influence of the following experimental parameters on the capturing rate was analyzed with a multiple logistic regression model: embolus diameter and length, CA diameter, flow quantity, type of filter, and type of testing. Results At the 5% level,except for flow quantity,a significant influence on the capturing rate could be demonstrated for the 6 factors mentioned above, the embolus diameter was the strongest influencing factor. In CA with diameters of 4,5,6,7 mm, the 8-wire filter captured (90?7)%, (91?8)%, (81?8)%,and (68?9)% of 0.5 mm emboli and (93?4)%, (95?6)%, (95?6)%,and (82?11)% of 1 mm emboli. In all, the smaller, the interlacing opening of the filter, the higher the capturing rate, and the presence of an embolus in a filter would decrease the capturing rate for the second embolus. Conclusion Retrievable artery filter is a promising cerebral protection device. The physical in vitro model is an effective alternative in studying the influence factors of the capturing rate of the filters.

Influence of cardiac motion on the velocity-time integrals of Doppler flow spectra: in vitro model study / 中华超声影像学杂志

Objective To investigate the influence of simulated heart motion on the Doppler spectrum velocity- time integral (VTI) of simulated blood flow measurements through an in vitro model. Methods Using heart-motion simulator model TD-3 designed by ourselves to note the feature of Doppler spectrum of simulated heart and simulated blood flow which moved separately and synchronously.The affection of the simulated heart's motion on the VTI of the simulated blood flow and their quantitative relationship were observed.Results When the simulated heart and blood flow moved synchronously, the VTI of the combined motion was the algebra sum of their VTI when their motion independently. The velocity and frequency of Doppler spectrum of simulated heart were unchanged. Conclusions The motion of simulated heart has a great influence on the value of Doppler blood flow spectrum VTI and this effect should be considered when blood flow volume was measured using Doppler's methods.