By analyzing the structure and the working principle of Evita 4 HPS valve (HPSV=high-pressure servo-valve) in the mixer unit, and introducing detailed status of troubleshooting to give the solvents. The repairing examples and some effective ways about maintenance of the HPSV are provided at last.

Fluke Electrical Safety analyzer (ESA-601) and Electrical Surgery analyzer(Model 454A)are used to measure some relative parameters of radio knife. By combining our measuring activity with the problems existing in the daily managements and usage of radio knife,our viewpoints are described in the following four aspects:management rules,electric shock prevention,patient electrode system and output power. An immature scheme about the quality control of radio knife is also put forward.

Stent implantation plays a more and more important role in the treatment of benign esophageal stenosis. Metal stents are most commonly used in the clinical practice, which can be classified into permanent stents and temporary retrieval stents. Permanent implantation of metal stents is easy to cause complications such as inflammatory hyperplasia, in-stent restenosis, perforation, bleeding, etc. Temporary retrieval stents should be removed with one week after it is implanted in order to avoid esophageal scar tissue repair and in-stent tissue hyperplasia, which can cause difficulty in its removing and produce higher recurrence rate of esophageal restenosis. Clinically, drug-eluting stents have already been used in cardiovascular system procedures, but at present the gastrointestinal drug-eluting stents are still in development and animal experiment stage. Biodegradable magnesium alloy stents have been widely employed in cardiovascular system procedures. With the rapid development of biological engineering materials, drug-eluting magnesium alloy stent has become a hot spot and the frontier in research field. This paper aims to make a comprehensive review about the current research status and prospect of the drug-eluting magnesium alloy stents, focusing on the stent technology, stent molding, coating modification, and the treatment of drug-eluting.

The study aims to improve the level of fine management of medical equipments, give full play to the functions and roles for better patient service, and explore methods for evaluating the benefits of medical equipment that can take into account and reflect the needs of multiple parties. Based on objectives and key results(OKR) methods and concepts, a benefit evaluation system was developed with the goal of giving full play to the functions and roles of medical equipments, with corresponding evaluation indexes and supervision and evaluation mechanisms formulated as well. This index system could take into account the needs and concerns of hospitals, the departments in use, the management authorities and patients at large, while contributing to process supervision and continuous improvement. In the OKR practice of large medical equipments(CT, MR) from 2018 to 2019, they had performed significantly better in inspections, inspection positive coincident rates, clinical service capabilities, maintenance assurance levels, patient satisfaction, scientific research and academics among others. The use of a medical equipment benefit evaluation system based on OKR concepts and methods can provide effective evaluation indicators for the operation and management of medical equipments. In addition, the system can maintain internal improvement momentum leveraging process supervision and continuous improvement methods, in order to assure the elevation of fine management level of medical equipments of modern hospitals, thus offering better medical services for patients at large.

Objective To study the defects of bone marrow-derived endothelial progenitor cells (EPCs) in number ratio and biological abilities (proliferation, adhesion and migration) in diabetic rats. Methods (1) Establishment of diabetic rat model:1%STZ solution was quickly injected into the abdominal cavity of the male SD rats with the dose of 60 mg/kg. (2). Isolation, culture and identification of bone marrow-derived EPCs in diabetic and normal rats. Bone marrow mononuclear cells were isolated from diabetic and normal rats by density gradient centrifugation methods and cultured by EGM-2 MV medium. The cells were identified by morphological observation, FITC-UEA-1 binding and Dil-Ac-LDL uptake assay, and fluorescent immunocytochemistry was used for detection of CD34 , CD133 and VEGFR-2 expression. CCK-8 method and Transwell kit method were used to determine biological activities of EPCs. Results (1) When cultured in vitro, both bone marrow-derived EPCs in diabetic and normal rats were fusiform in shape, the cells snuggled up to the wall. The expression of CD34, CDl33, VEGFR-2 could be detected in these cells, and the cells could uptake Dil-Ac-LDL and bind FITC-UEA-1, which proved that these cells were EPCs. (2) No significant difference in the number of EPCs derived from bone marrow existed between diabetic rats and normal rats, but the proliferation ability, migration ability and adhesion ability of bone marrow-derived EPCs in diabetic rats were obviously lower than those in normal rats. Conclusion The number of bone marrow-derived EPCs in diabetic rats is not obviously different from that in normal rats, but the biologic activity of EPCs derived from bone marrow in diabetic rats is degraded, which is manifested as weakened abilities of the proliferation, adhesion and migration.

Objective To discuss the clinical application of percutaneous radiologic gastrostomy (PRG) in treating dysphagia associated with amyotrophic lateral sclerosis (ALS),and to evaluate its safety and improvement effect on patient's nutritional status in ALS patients with pulmonary insufficiency.Methods The clinical data of 51 ALS patients who received PRG were retrospectively analyzed.The success rate of surgery and postoperative complications were recorded.All patients were regularly followed up,and the longterm complications as well as the one-,3-and 6-month mortality rates after the surgery were documented.The improvement of patient's nutritional status was evaluated.Results PRG was successfully accomplished in all 51 patients,the technical success rate was 100％.Mild postoperative complications occurred in 7 patients (13.73％) and severe massive hemorrhage in one patient (2.0％).After PRG,no signs or symptoms of impaired respiratory function were observed.No death occurred in one month and in 3 months after PRG.Six months after PRG,three patients died(6.8 ％,3/44).One month after PRG,31 patients had an increase in body weight of more than 1 kg,and the mean BMI was increased from preoperative t8.60±2.14 to postoperative 19.27±1.81 (one month after PRG),19.17±1.93 (3 month after PRG) and 18.89±2.33 (6 month after PRG).Conclusion For the performance of PRG no gastroscopy or anesthesia is needed,thus,the risk of aspiration asphyxia can be reduced in ALS patients complicated by pulmonary insufficiency and the success rate as well as the safety can be improved.Therefore,this technique is an effective means to ensure that the ALS patients with pulmonary insufficiency can get adequate energy intake to improve their nutritional status.

Objective:To explore the feasibility of using Double FLASH coronary CTA (CCTA) to evaluate myocardial blood perfusion based on the original Patlak Plots.Methods:A total of 50 subjects with non-ischemic heart disease were prospectively included in the study who received dynamic myocardial CT perfusion (CTP) and Double FLASH CTA scans in General Hospital of Tianjin Medical University from January 2018 to January 2020 due to coronary heart disease or suspected coronary heart disease. The age of the enrolled patients was at least 18 years old and there was no moderate or above stenosis on CTA. The dynamic CTP images were analyzed by using CTP analysis software on FRONTIER platform to calculate the CTP derived MBF (MBF CTP). While the CTA derived MBF (MBF CTA) was calculated from the CT attenuation values of both aorta and myocardium segments on two scanning time set of Double FLASH CTA which were measured by two independent radiologists. Pearson correlation and Bland-Altman analysis were used to compare the results of MBF CTP and MBF CTA. Results:There was a strong linear correlation between MBF CTP and MBF CTA measurements. In the mid anteroseptal level: MBF CTA=0.936MBF CTP-11.999, r2=0.600, P<0.01. In the mid anterolateral level: MBF CTA=1.010MBF CTP-9.206, r2=0.448, P<0.01. In the apex: MBF CTA=0.822MBF CTP+16.904, r2=0.375, P<0.01. Bland-Altman analysis also showed there were no significant differences between MBF CTP and MBF CTA measurements. Compared with dynamic CTP scan, Double FLASH CTA mode significantly reduced the radiation dose [(4.33±1.89) mSv vs. (1.38±0.19) mSv, t=4.378, P=0.030]. Conclusions:This study validated the feasibility and accuracy of the MBF CTA measurement based on the theory of Patlak Plots only using Double FLASH CTA images. This method might have the potential to expand the clinical application of one-stop CTP examination for simultaneously evaluating coronary artery and myocardial ischemia in the clinic.

Objective: Although previous studies have validated the effect of childhood trauma on depressive level, few studies have utilized the diathesis-stress theory to investigate the specific roles of perceived stress and rumination in the pathway between childhood trauma and depression in Chinese college students. This study aims to demonstrate the mediation effect of perceived stress and the moderation effect of rumination in the pathway between childhood trauma and depressive level in Chinese college students. Methods: A total of 995 Chinese college students in Guangzhou were included in this study by recruitment advertisement from October to December 2021. And they were asked to finish four self-report questionnaires, including Childhood Trauma Questionnaire-Short Form, Perceived Stress Scale, the 22-item Ruminative Response Scale, and Beck Depression Scale-II. Then the data were analyzed with Mplus 8.3. Results: Results revealed significant correlations among childhood trauma, perceived stress, rumination and depressive level. Further analyses revealed that perceived stress played a mediation role between childhood trauma and depressive level (estimate=0.09, standard error [SE]=0.02, t=5.93, 95% confidence interval [CI]=0.06–0.12), and rumination played a moderation role between childhood trauma and perceived stress (estimate=-0.17, SE=0.06, t=-2.86, 95% CI=-0.28– -0.05]) as well as between childhood trauma and depressive level (estimate=0.10, SE=0.04, t=2.74, 95% CI=0.03–0.16). Conclusion These results revealed the mediation effect of perceived stress and the moderation effect of rumination in the pathway between childhood trauma and depressive level in Chinese college students, which helped us to understand how the childhood trauma influenced the depressive level and gave us multi-dimensional indications for reducing the effect of childhood trauma on depressive level.

Objective:To investigate whether hepatitis B virus X protein (HBx) mediates the podocyte injury through reactive oxygen species (ROS) /nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3) signaling pathway.Methods:HBx-overexpressing lentivirus was transfected into renal podocytes of mouse to mimic the pathogenesis of hepatitis B virus-associated glomerulonephritis. Podocytes were divided into the following five groups: blank control group (no special treatment), negative control group (transfected with control lentivirus), HBx overexpression group (transfected with HBx overexpression lentivirus), HBx overexpression+NLRP3 siRNA group (transfected with HBx overexpression lentivirus and NLRP3 siRNA), and HBx overexpression+ROS inhibitor group (transfected with HBx overexpression lentivirus and adding ROS inhibitor). The morphological changes of podocytes were observed with electron microscope. The generation of ROS was detected by dichlorodihydrofluorescein diacetate assay (DCFH-DA). Hoechst 33342 staining was used to observe the morphological and quantitative changes of podocyte nuclei. Enzyme-linked immunosorbent assay was used to detect caspase-1 activity, and the levels of lactate dehydrogenase, interleukin (IL)-1β and IL-18. Quantitative real-time polymerase chain reaction and Western blotting were used to detect the expression levels of mRNA and protein of pyroptosis-related protein, such as NLRP3, apoptosis-associated speck-like protein containing card (ASC), caspase-1, IL-1β and IL-18. TUNEL staining and flow cytometer were used to detect the number of pyroptosis cells. Immunofluorescence staining was used to detect the expression levels of desmin and nephrin.Results:After successful infection of podocytes with HBx-overexpressing lentivirus, pyroptosis-related morphological changes in the cells were observed under electron microscope. The level of ROS in the HBx overexpression group was significantly higher compared to the negative control group ( P<0.05). Hoechst 33342 staining revealed condensed nuclei in the HBx overexpression group. TUNEL staining and flow cytometer demonstrated that podocytes underwent increased pyroptosis in the HBx overexpression group. The mRNA and protein expression levels of pyroptosis-related proteins such as NLRP3, ASC, caspase-1, IL-1β and IL-18 were up-regulated upon HBx overexpression (all P<0.05). Caspase-1 enzyme activity, lactate dehydrogenase and desmin expression levels were enhanced after HBx overexpression (all P<0.05). However, NLRP3 knockdown or addition of ROS inhibitors attenuated the pyroptosis and increased expression levels of pyroptosis-related proteins caused by HBx overexpression (all P<0.05). Conclusion:ROS/NLRP3 pathway plays an important role in HBx-induced podocyte pyroptosis.

Objective: We aimed to investigate the differences of transcriptome profile between 2 groups of high-grade serous ovarian cancer (HGSOC) patients with distinct outcomes and identify potential biomarkers for recurrence. Methods: RNA sequencing was performed in 2 groups of HGSOC patients with similar demographic characteristics but exhibiting distinct progression-free survival (PFS). Transcriptome data of poor response (PR; PFS ≤6 months) and good response (GR; PFS ≥12 months) group were compared. We employed xCell to evaluate the abundance of 63 cells in tumor microenvironment. The predictive value of recurrence-related tumor infiltration cells was validated in cohort data from Gene Expression Omnibus (GEO) and The Cancer Genome Atlas (TCGA) dataset. The weighted correlation network analysis was performed to identify the genes related to cell infiltration. Results: PR patients exhibited a distinct tumor infiltration immune cells-related transcriptional profile compared to GR patients, such as lower signatures of leukocyte differentiation, activation and chemotaxis. The fraction of T-helper 2 (Th2) cells infiltration was significantly higher in PR group than in GR group. High infiltration of Th2 was significantly associated with unfavorable prognosis in the GEO cohort (area under the curve=0.84 at 6 months recurrence) and TCGA cohort (p=0.008). Genes enriched to extracellular matrix organization and integrin binding were relevant to Th2 infiltration. Conclusion Patients with HGSOC having shorter PFS exhibited a distinct gene signature that related to tumor-infiltrating immune cells. The level of Th2 infiltration could facilitate patient recurrence risk stratification and may be a promising biomarker for prognosis prediction and immune-related treatment.