OBJECTIVES: A ventricular assist device (VAD) is an electromechanical device used to assist cardiac blood circulation, which can be employed for the treatment of end-stage heart failure and is most commonly placed in the left ventricle. Despite enhancing perfusion performance, the implantation of left ventricular assist device (LVAD) transforms the local intraventricular flow and thus may increase the risk of thrombogenesis. This study aims to investigate fluid-particle interactions and thromboembolic risk under different LVAD configurations using three-dimensional (3D) reconstruction models, focusing on the effects of outflow tract orientation and blood flow rates. METHODS: A patient-specific end-diastolic 3D reconstruction model was initially constructed in stereo lithography (STL) format using Mimics software based on CT images. Transient numerical simulations were performed to analyze fluid-particle interactions and thromboembolic risks for LVAD with varying outflow tract orientations under 2 flow rates (4 L/min and 5 L/min), using particles of uniform size (2 mm), and a blood flow rate optimization protocol was implemented for this patient. RESULTS: When the LVAD flow rate was 5 L/min, helicity and flow stagnation of the blood flow increased the particle residence time (RT) and the risk of thrombogenesis of the aortic root. The percentage of particles traveling toward the brachiocephalic trunk was up to 20.33%. When the LVAD flow rate was 4 L/min, blood turbulence in the aorta was reduced, the RT of blood particles was shortened, and then the percentage of particles traveling toward the brachiocephalic trunk decreased to 10.54%. When the LVAD blood flow rate was 5 L/min and the direction of the outflow pipe was optimal, the RT of blood particles was shortened, and then the percentage of particles traveling toward the brachiocephalic trunk decreased to 11.22%. A 18-month follow-up observation of the patient revealed that the LVAD was in good working order and the patient had no complications related to the implantation of LVAD. CONCLUSIONS Implantation of LVAD results in a higher risk of cerebral infarction; When implanting LVAD with the same outflow tract direction, optimizing flow velocity and outflow tract can reduce the risk of cerebral infarction occurrence.
Heart-Assist Devices/adverse effects* ; Humans ; Heart Failure/physiopathology* ; Blood Flow Velocity ; Thromboembolism/prevention & control* ; Models, Cardiovascular ; Heart Ventricles/physiopathology* ; Imaging, Three-Dimensional

Objective:Ventricular septal defect(VSD)is a prevalent congenital cardiac anomaly.By enhancing the occluder design and optimizing procedural approaches,the indications for VSD closure can be broadened while minimizing associated complications.The utilization of fully biodegradable occluder holds promising potential in resolving conduction block issues encountered during VSD closure.This study aims to compare the results of the fully biodegradable occluder with the metal occluder in transoesophageal echocardiography-guided VSD closure via lower sternal level minor incision at the interim follow-up,and to find risk factors for the occurrence of electrocardiographic and valvular abnormalities postoperatively. Methods:We reviewed the postoperative and 3-year follow-up data of all patients who underwent the randomized controlled study of VSD closure from January 1 to November 7,2019 in the Second Xiangya Hospital of Central South University.The safety and efficacy of the procedure were assessed and compared between the 2 groups by electrocardiogram and echocardiography results,and the risk factors for the occurrence of postoperative electrocardiogram and valve abnormalities were studied with Logistic regression analysis. Results:Twelve and fifteen patients underwent VSD closure with the metallic occluder and the fully biodegradable occluder,respectively.All patients survived during the follow-up period without major complications such as atrioventricular block,significant residual shunt,too rapid absorption of the occluder,and significant valvular regurgitation.There were no significant differences in the results of electrocardiograph and color Doppler ultrasonography the metal occluder group and the fully biodegradable occluder group 1,2,and 3 years after operation(all P>0.05).The size of the occluder were risk factors for tricuspid regurgitation at 2 and 3 years postoperatively,and the difference between the occluder size and the VSD defect size were risk factors for tricuspid regurgitation at 2 years postoperatively(P<0.05). Conclusion:This study adequately demonstrates the safety and efficacy of fully biodegradable occluders in small VSD closure and shows the same postoperative effects as conventional nitinol occluders.

Gravity is one of the most widespread mechanomechanical signals affecting surface organisms and plays a key role in maintaining normal cardiovascular structure and function.The absence of gravity in the space environment leads to changes in the physiological-mechanical environment of the cardiovascular system,potentially causing adaptive changes or remodelling of the cardiovascular system in terms of structure and function.However,how the cardiovascular system senses,transduces,and responds to altered mechanical stress in the microgravity environment remains poorly understood by humans.In this paper,we reviewed the research findings on mechanoreceptors and mechano-transduction of cardiovascular system in recent years,analyzed the mechanisms of mechanical perception and response to microgravity in cardiovascular system,and predicted the novel mechanoreceptors,key signaling pathways,and potential targets for intervention in space microgravity.This article aims to provide new ideas for combating adaptive changes in the cardiovascular system due to space microgravity.

OBJECTIVE To study the improvement effect and possible mechanism of N-butylphthalide on inflammatory injury of bone marrow mesenchymal stem cells （BMSCs） in rats. METHODS BMSCs of rats were divided into control group， model group， N-butylphthalide low-concentration， medium-concentration and high-concentration groups （10， 20， 50 μmol/L）. BMSCs were cultured in vitro and lipopolysaccharide （the final concentration of 10 mg/L） was used to establish the inflammatory injury model. After the intervention of N-butylphthalide， the survival rate， apoptotic rate， the contents of tumor necrosis factor α （TNF- α）， interleukin 1β （IL-1β） and IL-6 in cell culture medium， the mRNA expression of nuclear factor-κB（NF-κB） p65， and the protein expressions of caspase-3， B-cell lymphoma 2 （Bcl-2）， Bcl-2 related X protein （Bax） and NF-κB p65 in cells were detected. RESULTS Compared with control group， the survival rate and protein expression of Bcl-2 were decreased significantly in model group （P＜0.05）； the apoptotic rate， contents of TNF-α， IL-1β and IL-6， the mRNA expression of NF-κB p65， and the protein expressions of caspase-3， Bax and NF-κB p65 were increased significantly （P＜0.05）. Compared with model group， above indexes were significantly reversed in all concentration groups of N-butylphthalide （P＜0.05）， in concentration-dependent manner. CONCLUSIONS N-butylphthalide can ameliorate the inflammatory injury of BMSCs induced by lipopolysaccharide， and its mechanism may be related to the inhibition of NF-κB signaling pathway.

Objective:To explore the application effect of massive open online course (MOOC) combined with peer mutual assistance in cardiopulmonary resuscitation teaching.Methods:A total of 140 students in the same class of Batch 2015 were divided into the experimental group and the control group. In the teaching of cardiopulmonary resuscitation, the experimental group was based on the MOOC teaching platform, watched videos and topic tests before class, and used the peer mutual assistance in class. While the control group adopted traditional classroom teaching mode. The teaching effect of the two groups were evaluated by comparing the operation assessment scores and questionnaire survey of students' satisfaction with teaching. SPSS 22.0 was used for t-test and Chi-square test. Results:The operating assessment score of the experimental group was (82.20±2.31), and the operating assessment score of the control group was (75.80±1.72). The difference was statistically significant ( t=3.27, P<0.05). The questionnaire survey showed that the course satisfaction and learning motivation of the experimental group were better than those of the control group. In learning burden, the two groups had similar results ( P=0.739). Conclusion:MOOC combined with peer mutual assistance in cardiopulmonary resuscitation teaching can help students better master skills, improve students' course satisfaction and learning motivation, without increasing their learning burden.

Hip fracture is considered as the most severe osteoporotic fracture characterized by high disability and mortality in the elderly. Improved surgical techniques and multidisciplinary team play an active role in alleviating prognosis, which places higher demands on perioperative nursing. Dysfunction, complications, and secondary impact of anaesthesia and surgery add more difficulties to clinical nursing. Besides, there still lack clinical practices in perioperative nursing for elderly patients with hip fracture in China. In this context, led by the Orthopedic Nursing Committee of Chinese Nursing Association, the Expert consensus on clinical practice in perioperative nursing for elderly patients with hip fracture ( version 2023) is developed based on the evidence-based medicine. This consensus provides 11 recommendations on elderly patients with hip fracture from aspects of perioperative health education, condition monitoring and inspection, complication risk assessment and prevention, and rehabilitation, in order to provide guiding advices for clinical practice, improve the quality of nursing and ameliorate the prognosis of elderly patients with hip fracture.

Objective:To explore the risk factors for death within 1 year after hip fracture surgery in the elderly.Methods:A case control study was made on the clinical data of 551 elderly patients with hip fracture treated in Second Affiliated Hospital of Soochow University from January 2019 to December 2020, including 182 males and 369 females; aged 65-100 years [80(73,86)years]. Joint replacement, cannulated screw fixation or proximal femoral nail fixation were performed. The patients were divided into survival group ( n=494) and death group ( n=57) based on the death within 1 year after surgery recorded at postoperative telephone follow-up. The gender, age, hypertension, diabetes, cardiovascular diseases, chronic respiratory diseases, neurological diseases, chronic renal failure, anemia on admission, fracture types, American anesthesiologist Association (ASA) classification, operative methods, preoperative waiting time, duration of operation and perioperative blood transfusion were recorded in two groups. Univariate Cox regression was used to analyze the correlation between the above indexes and death within 1 year after surgery. All indexes with P<0.2 in the univariate analysis were included in multivariate Cox regression analysis to clarify the independent risk factors for death within 1 year after surgery. Results:Univariate Cox regression analysis showed that death within 1 year after surgery correlated with gender, age chronic respiratory diseases, chronic renal failure and anemia on admission (all P<0.01), but not with hypertension, diabetes, cardiovascular diseases, neurological diseases, fracture types, ASA classification, operative methods, preoperative waiting time, duration of operation or perioperative blood transfusion (all P>0.05). Multivariate Cox regression analysis showed that male ( HR=2.08, 95% CI 1.20, 3.61, P<0.01), age ≥ 80 years ( HR=2.22, 95% CI 1.15, 4.28, P<0.05), chronic respiratory diseases ( HR=2.54, 95% CI 1.19, 5.40, P<0.05), chronic renal failure ( HR=4.57, 95% CI 1.27, 16.44, P<0.05), anemia on admission ( HR=2.82, 95% CI 1.38, 5.76, P<0.01) were significantly associated with death within 1 year after surgery. Conclusion:Male age≥ 80 years, chronic respiratory disease, chronic renal failure and anemia on admission are independent risk factors for death within 1 year after hip fracture surgery in the elderly.

Objective:To analyze the clinicopathological features of intraabdominal bronchogenic cyst.Methods:The clinical data of 8 patients with intraabdominal bronchogenic cyst admitted in 3 Grade-A tertiary hospitals in Yunnan province between 2014 and 2023 were retrospectively analyzed. The clinical and pathological features, diagnosis, treatment and prognosis of intraabdominal bronchogenic cyst were reviewed.Results:There were 1 male and 7 females with an mean age of 45±12 years (21-65 years). Two patients presented with abdominal pain and 5 asymptomatic patients were found during physical examination. The cysts were located in retroperitoneum in 4 cases, located between the pancreas tail, spleen and the posterior wall of the stomach in 2 cases, located in the posterior wall of the stomach in 1 case, and located close to left adrenal gland in 1 case. Two patients had elevated tumor markers, while tumor markers in the remaining 6 cases were normal. Seven cases underwent laparoscopic complete cyst resection and 1 case had open surgical resection. The wall of most cysts were lined with respiratory epithelium and composed of goblet cells or pseudostratified ciliated columnar epithelium. The wall of cysts was composed of fibrous connective tissue or smooth muscle bundles, and the cavity contained serous mucous glands. Two cases showed cartilage tissue and one showed the infiltration of large number of inflammatory cells. The mean follow-up time was 31±32 months (range 5-107 months), and no recurrence or metastasis was found during the follow-up.Conclusions:Abdominal bronchogenic cyst is often found in adulthood, and most cases are symptomatic and found during physical examination. The diagnosis mainly depends on pathological examination, and tumor markers are not specific for its diagnosis. Surgery is the best way for treatment.

Objective:To explore the methods to improve the professional core competencies of medical students in the standardized residency training.Methods:A total of 82 medical students who participated in the standardized residency training ("resident students" for short) in the same period were selected in this study, and the self-edited professional core competencies textbooks were used for regular theoretical study, and at the same time, clinical practice cases were collected for regular scenario reduction teaching. When the resident students entered the department and after 12 months of the standardized training, the professional core competencies training evaluation scale was used to evaluate and compare the scores of the resident students, and the value of the above-mentioned training model to improve the professional core competencies of the resident students was evaluated. SPSS 18.5 was performed for t test between groups. Results:After being trained by the above model, the selected students had significantly improved such competencies as communication, cooperation and problems solving ( P<0.05). Compared with the scores of resident students before and after the training, there was no significant difference in communication and cooperation with other students ( P>0.05), with low satisfactory communication with the leader ( P>0.05), but the problem-solving ability had been significantly improved ( P<0.05), while the score of which was low and it should be pay more attention to in the future training. Conclusion:In the process of standardized residency training, the application of the above-mentioned training model can significantly improve the professional core competencies of resident students, and at the same time, it's necessary to strengthen the cultivation of satisfactory communication with leaders and problem solving ability.

Objective: To investigate the clinical features and pathogenic genes of a family with osteosclerosis. Methods: Six patients and six family members from a family in Jiangsu were tested for biochemical parameters, bone metabolic markers, bone mineral density, thoracolumbar anterior lateral slices, skull positive lateral radiographs, and pelvic plain films. Meanwhile, Sanger sequencing was performed to detect gene mutations of the proband and five other family members with high bone mass. The conformation of the mutational low-density lipoprotein receptor-related protein 5 (LRP5) protein was predicted by SWISS-MODEL. Results: Four adult patients (one male and three females) were tall, with mandibular enlargement and kyphosis in the center of the lower jaw, and none of the four had fractures. Their X ray examination revealed that the skull and long bone cortex was thickened, while the sella and mandible was enlarged. In addition, the absolute values of bone mineral density at each site of all patients were significantly higher as compared with the standard age- and sex-matched adults or adolescent mean reference values, with Z scores of L2-4, femoral neck and total hip being (6.31±4.03) SD, (6.56±2.36) SD, and (7.19±2.03) SD, respectively. The results of genetic sequencing revealed that all six patients carried a heterozygous mutation (c.331G>T; D111Y) in exon 2 of LRP5 gene, while other family members showed wild type (c.331G>G; D111D). Functional prediction indicated that this mutation was located at the amino acid terminal of exon 2 of LRP5 gene, which encodes the first β-helix-generating region of LRP5 protein. Conclusion The D111Y mutation in LRP5 gene leads to a clinical phenotype characterized by benign increased bone mineral density without increasing the risk of fracture. This mutation may further affect the downstream Wnt signaling pathway by altering the spatial structure of LRP5 protein, thereby promoting maturation and differentiation of osteoblasts and resulting in osteosclerosis.