Objective:To investigate the relationship between intramuscular adipose tissue index (IATI) calculated from computed tomography images at transverse process of the first lumbar and all-cause mortality in maintenance dialysis patients, and to provide a reference for improving the prognosis in these patients.Methods:It was a multicenter retrospective cohort study. The clinical data of patients who received maintenance hemodialysis or peritoneal dialysis treatment from January 1, 2017 to December 31, 2019 in 4 grade Ⅲ hospitals including Zhongda Hospital Affiliated to Southeast University, Taizhou People's Hospital Affiliated to Nanjing Medical University, Affiliated Hospital of Yangzhou University, and the Third Affiliated Hospital of Soochow University were retrospectively collected. IATI was calculated by low attenuation muscle (LAM) density/skeletal muscle density. The receiver-operating characteristic curve was used to determine the optimal cut-off value of IATI, and the patients were divided into high IATI group and low IATI group according to the optimal cut-off value. The differences of baseline clinical data and measurement parameters of the first lumbar level between the two groups were compared. The follow-up ended on December 23, 2022. The endpoint event was defined as all-cause mortality within 3 years. Kaplan-Meier survival curve and log-rank test were used to analyze the survival rates and the differences between the two groups. Multivariate Cox regression analysis models were used to analyze the association between IATI and the risk of all-cause mortality in maintenance dialysis patients. Multivariate logistic regression analysis model was used to analyze the influencing factors of high IATI.Results:A total of 478 patients were eligibly recruited in this study, with age of (53.55±13.19) years old and 319 (66.7%) males, including 365 (76.4%) hemodialysis patients and 113 (23.6%) peritoneal dialysis patients. There were 376 (78.7%) patients in low IATI (<0.42) group and 102 (21.3%) patients in high IATI (≥0.42) group. The proportion of age ≥ 60 years old ( χ2=24.746, P<0.001), proportion of diabetes mellitus ( χ2=5.570, P=0.018), fasting blood glucose ( t=-2.145, P=0.032), LAM density ( t=-3.735, P<0.001), LAM index ( t=-7.072, P<0.001), and LAM area/skeletal muscle area ratio ( Z=-9.630, P<0.001) in high IATI group were all higher than those in low IATI group, while proportion of males ( χ2=11.116, P<0.001), serum albumin ( Z=2.708, P=0.007) and skeletal muscle density ( t=12.380, P<0.001) were lower than those in low IATI group. Kaplan-Meier survival analysis showed that the 3-years overall survival rate of low IATI group was significantly higher than that in high IATI group (Log-rank χ2=19.188, P<0.001). Multivariate Cox regression analysis showed that IATI<0.42 [<0.42/≥0.42, HR(95% CI): 0.50 (0.31-0.83), P=0.007] was an independent protective factor of all-cause mortality, and age ≥60 years old [ HR (95% CI): 2.61 (1.60-4.23), P<0.001], diabetes mellitus [ HR (95% CI): 1.71 (1.06-2.78), P=0.029] and high blood neutrophil/lymphocyte ratio [ HR (95% CI): 1.04 (1.00-1.07), P=0.049] were the independent risk factors of all-cause mortality in maintenance dialysis patients. Stepwise Cox regression analysis showed that IATI<0.42 was still an independent protective factor of all-cause mortality in maintenance dialysis patients [<0.42/≥0.42, HR (95% CI): 0.45 (0.27-0.76), P=0.003]. Multivariate logistic regression analysis showed that low skeletal muscle density [ OR (95% CI): 0.84 (0.81-0.88), P<0.001] and high serum triglyceride [ OR (95% CI): 1.39 (1.07-1.82), P=0.015] were the independent influencing factors of IATI≥0.42. Conclusion:IATI<0.42 of the first lumbar level is an independent protective factor of all-cause mortality in maintenance dialysis patients. Localized myosteatosis within high-quality skeletal muscle may reduce the risk of all-cause mortality in these patients.

Objective To analyze the correlation of the left common iliac vein(LCIV)diameter and the lower extremity deep venous thrombosis(DVT)by direct multi spiral computed tomography venography(MSCTV).Methods The MSCTV images of 218 patients with lower extremity DVT(DVT group)and the enhanced CT images of 168 patients in the control group were analyzed retrospectively.The diameter of the LCIV was measured and the compression degree was evaluated.Results In the DVT group,the diameter of the LCIV significantly reduced,with an average value of(5.150±2.352)mm.In the control group,the average diameter of the LCIV was(6.401±2.550)mm.The difference between the two groups was statistically significant(Z=-5.453,P＜0.05).The degree of compression in the LCIV was 61％(50％-95％)in the DVT group and 39.6％(0％-73％)in the control group,showed a statistically significant difference(Z=-10.555,P＜0.05).There were statistically significant differences in LCIV diameter between males and females within both DVT and control groups(P＜0.05),and there were no statistically significant differences in LCIV compression degree between males and females within both DVT and control groups(P＞0.05).Regression analysis showed a positive correlation between LCIV diameter and lower extremity DVT.Conclusion The lower extremity MSCTV enables accurate diagnosis of DVT by visualizing compression of the LCIV and quantifying its degree of compression.A reduced diameter of the LCIV is an independent risk factor for lower extremity DVT.

Objective:To investigate the application effect of the blended teaching model of "pre-class synchronous small private online course (SPOC)+ flipped classroom+post-class knowledge expansion" in the theoretical teaching of biochemistry and molecular biology. Methods:A total of 951 students majoring in clinical medicine, preventive medicine, and pharmacy in the class of 2020 in Qiqihar Medical College were selected as teaching reform research group (experimental group), and their curriculum relied on the self-built massive open online course (MOOC) curriculum and the MOOC resources of Chinese universities to construct a blended teaching model; the reform methods such as small class grouping, case-based learning, and diversified examination were adopted to carry out theoretical flipped teaching activities with cross integration of cases and knowledge points as the main line. A total of 847 students majoring in clinical medicine, preventive medicine, and pharmacy in the class of 2019 were selected as control group, and the traditional teaching method was used for theoretical courses. The courses were evaluated by offline assessment and online assessment, and feedback information was collected through examination scores, questionnaire survey, and online voting. SPSS 20.0 was used for statistical analysis, and the t-test was used for comparison between groups. Results:The experimental group had a significantly higher total score of final examination than the control group [(92.12±3.88) vs. (86.73±5.27), P<0.05]. The questionnaire survey showed that the students in the experimental group showed a relatively high degree of satisfaction with the blended teaching reform, which increased their participation, experiencing, and sharing activities. The students majoring in clinical medicine in the class of 2020 believed that they had established clinical thinking ability (263, 92.61%) and become familiar with the clinical manifestations and pathogenesis of common diseases (262, 92.25%); the students majoring in preventive medicine in the class of 2020 believed that they had increased their awareness of serving the public (151, 93.21%) and developed the ability to teach and guide healthy living (148, 91.36%); the students majoring in pharmacy in the class of 2020 believed that they had mastered the mechanism of action of drugs for disease treatment (138, 93.24%) and understood the importance of rational drug use in clinical practice (135, 91.22%). Conclusion:The blended teaching model realizes student-centered teaching, stimulates the interest and initiative in learning, and improves learning outcome, thereby improving teaching quality to a certain extent.

[Abstract] Objective: To investigate the effect of HMGB1 gene on the growth of human epithelial ovarian cancer xenografts in nude mice, and to lay a foundation for finding new targets for the treatment of ovarian cancer. Methods: Human epithelial ovarian cancer SKOV3 cells in logarithmic growth phase were selected to establish a human epithelial ovarian cancer xenograft model in nude mice. Nude mice with successful model establishment were randomly divided into control group and HMGB1-siRNA group. On the 7th, 9th, 11th, 14th, and 16th days after cell inoculation, the same amount of saline and HMGB1-siRNA were respectively injected into two groups of mice under the armpit.After 3 weeks, the nude mice were sacrificed by cervical dislocation, the tumor tissues were separated, and the volume of the tumor was measured. The apoptosis of transplanted tumor cells was detected by Tunnel staining. The expressions of HMGB1, STAT3 and p-STAT3 were detected by Western blotting. The expression of vascular endothelial growth factorA(VEGF-A) and microvascularization were detected by immunohistochemistry. Results: Compared with the control group, the growth of tumor volume slowed down in HMGB1 siRNA group, and on the 21st day, the tumor volume of HMGB1-siRNA group was significantly smaller than that of the control group (P<0.05). HMGB1-siRNA successfully knocked down the expression of HMGB1 mRNA in transplanted tumor tissue. The apoptosis rate of tissue cells in HMGB1-siRNA group was significantly increased ([34±8]% vs [6±2]%, P=0.04), and the expressions of HMGB1 and p-STAT3 were significantly reduced (P<0.05). The expression of VEGF-Aand the number of microvessels were significantly lower than those of the control group (both P<0.05). Conclusion: Knockdown of HMGB1 gene reduces the expression of VEGF-A and microvessel formation possibly by inhibiting the HMGB1/STAT3 signaling pathway, thereby promoting the apoptosis of tumor tissues and slowing the growth of xenografts.

Objective To explore the method and effect of applying just-in-time-teaching (JiTT) mode in the reform of the teaching method of biochemical comprehensive experiment (Isolation, Purification and Identification of γ-Globulin From serum). Methods A total of 100 undergraduate students in our 2016 clinical medicine were divided evenly into two groups: the control group and the experimental group. The control group used traditional teaching, and the experimental group used JiTT-based teaching. In the experimental group, an online environment for pre-classroom discussion and feedback was constructed by uploading learning resources such as short video and tutorials to the online teaching platform and the online learning exchange group 3-5 days before the class; the class session itself consisted of personal tests, face-to-face teaching by teachers, group discussion, finishing experimental report and answering questions etc., and was intended to evaluate the students' self-study. SPSS 22.0 was used to collect exam scores and questionnaire results, and the data between groups were compared using t test. Results The scores of individual test scores in the experimental group (9.44±0.59) were higher than those in the control group (8.77±0.41) (P=0.00), and the difference was statistically significant. In all the six questionnaire items pertaining to teaching effect , JiTT teaching method received higher scores than the traditional teaching method (P<0.05), and the difference was statistically significant. Conclusion JiTT can improve the quality of biochemistry experiment teaching. It is worthwhile to try it in the teaching of other basic specialized courses.

Objective: To discuss the success rate and image quality in pediatric patients who used chloral hydrate before their cone beam computed tomography exam. Methods: 1752 patients aged 1 to 6 were selected for this retrospective study. They were divided into sedated group (219 cases) and non-sedated group (1 533 cases). The success rate and image quality were compared between two groups. Results: The sedated group had a higher success rate to non-sedated group: 99.5%(218/219) vs. 90.4% (1 386/1 533). The motion artifact in sedated group was lower than non- sedated group with I degree: 4.8% (15/314) vs. 20.1%(327/1 630) and II degree: 0.3%(1/314) vs. 12.2%(199/1 630). Conclusion Giving chloral hydrate to pediatric patients before their CBCT exam would improve both success rate and image quality, and reduce unnecessary radiation expose.

?? [Abstract]? Objective? To explore the effects of perioperative humanistic care on medium and advanced gynecologic malignant tumor patients. Methods? From January 2015 to December 2016, we selected 102 medium and advanced gynecologic malignant tumor patients at Beijing Obstetrics and Gynecology Hospital of Capital Medical University. Humanistic care was carried out during the perioperative period. We observed postoperative recovery, psychological state and the incidence of complications among patients. Results? Patients were all with successful operations, stable psychological state and no complications, and they discharged from hospitals steadily. Conclusions? Perioperative humanistic care has important clinical significance in improving psychological state among medium and advanced gynecologic malignant tumor patients and promoting patients' recovery.

Objective To report the clinical features, myopathological changes, and gene mutations in five Chinese patients with mitochondrial diseases caused by POLG gene mutations. Methods Clinical materials of five unrelated patients who were referred to Department of Neurology, Peking University First Hospital from April 2012 to January 2018, carrying POLG gene mutations, were retrospectively analyzed. Muscle/nerve biopsies and targeted second-generation gene sequencing were performed on the patients. Results Among the five patients, three were male and two were female. Two cases were dominant inheritance and three were sporadic or recessive inheritance. The ages of onset were from 15 to 40 years with disease course of one to 26 years. One of them showed atypical SANDO (sensory ataxic neuropathy, dysarthria, and ophthalmoparesis) syndrome accompanied by cardiac preexcitation syndrome. There were two cases with autosomal dominant and one case with recessive progressive external ophthalmoplegia plus syndrome. One case presented with cognitive delay and sensory neuropathy. The pathological changes of mitochondrial myopathy were observed in all four patients with muscle involvement. Sural nerve biopsy in the patient with cognitive delay and sensory ataxia revealed chronic axonal pathological changes. POLG gene mutations were found in all five patients by targeted next generation sequencing, including single heterozygous mutations in two dominant inherited patients (c. 914 G＞A and c. 2864A＞G, respectively), and compound heterozygous POLG gene mutations in the other three sporadic/recessive inherited patients (c. 2591 A＞G/c. 1790 G＞A, c. 924G＞T/c. 3002delG and c. 1613A＞T/c. 1612 G＞T, respectively). There were six novel mutations not reported before, i.e., c.914G＞A(p.S305N), c.924G＞T(p.Q308H), c.1613A＞T(p.E538V), c.1612G＞T(p.E538*), c.1790 G＞A(p.R597Q) and c.3002delG. Conclusions POLG gene mutations can lead to different clinical spectrums. Progressive external ophthalmoplegia, limb weakness and axonal sensory neuropathy are common presentations in this group of patients with POLG gene related mitochondrial neuromuscular diseases. Novel mutations found in this study expand the mutational spectrum of POLG gene.

Objective: To investigate the sonographic findings of fetal congenital absence of the ductus venosus (ADV) and its effect on the prognosis of fetus. Methods: The ultrasonographic features of 11cases of fetal ADV deficiency diagnosed from December 2013 to June 2017 were retrospectively analyzed, and the fetal prognosis was followed up. Results: Of the 11 cases, umbilical vein flew directly back to the right atrium in 7 cases; umbilical vein connected with the inferior vena cava in 1 case; umbilical vein directly flowed into the iliac vein in 1 case; umbilical vein and portal vein connection in the other 2 cases. Of the 11 cases, 4 cases were solitary and had no abnormality after birth; 5 cases were complicated with abnormal structure of intracardiac and extracardiac system; 2 cases were only followed with abnormal extracardiac system. Of the 5 complicated cases, 1 case was double chorionic twin amniotic membrane pregnancy (the second fetuse had no obvious abnormality) and died after birth; the other 4 cases were terminated before 28 weeks of gestation. Of the 2 complicated cases, 1 case was followed with severe digestive tract abnormalities and died after birth, and the other one was followed with single umbilical artery and hydramnion. Conclusions Color Doppler ultrasonography is an important means for prenatal screening of fetal ADV.The prognosis of patients with solitary ADV without fetal cardiac dysfunction is good.The prognosis is poor to patients with severe intracardiac and extracardiac abnormality. There is a correlation between the ADV and fetal chromosomal abnormalities. If pregnancy is necessary, fetal chromosome examination should be recommended first and cardiac function should be followed up closely by ultrasound.

Objective To discuss the effect of the teaching mode of technological pedagogical and content knowledge in biochemistry theory teaching. Methods 400 students in 8 classes of clinical medicine undergraduate in Grade 2013 were selected and randomly divided into 2 groups. The traditional teaching mode was applied in the control group of 198 students in 1-4 classes, while the technological pedagogical and content knowledge teaching mode was applied in the experimental group of 202 students in 5-8 classes. 385 students in 8 classes of clinical medical undergraduates in Grade 2014 were selected and randomly divided into 2 groups. The control group of 189 students in 1-4 classes adopted the traditional teaching mode, while the experimental group of 196 students in 5-8 classes adopted the technological pedagogical and content knowledge teaching mode, which used the micro-lesson and network platform as learning resource superior to the flipped classroom. Flipped classroom was divided into two major learning links:extracurricular self-study and class digestion. Through the network platform the micro-lesson was presented to the learners. Learners could make self-study according to their own specific circumstances and in the classroom many activities were increased such as the mutual cooperation between the students, the students' PPT teaching, the students' questions and the discussion, and the interaction between teachers and students, etc. The results of the examinations of the two terms students of the same profession and the questionnaire were analyzed. The related data were processed by SPSS 15.0, and the data between groups were compared by t test . Results The test scores analysis showed that the individual test scores in experimental group of Grade 2013 were [(17.94±2.02) vs. (12.28±4.17)], and the individual test scores in experimental group of Grade 2014 were [(18.21 ±1.78) vs. (12.45 ±5.13)], which were obviously higher than the control group, and there was statistical significance. The final exam scores in experimental group of Grade 2013 were [(78.28±11.18) vs. (68.65±12.51)], and the final exam scores in experimental group of Grade 2014 were [(81.73 ±9.12) vs. (74.41 ±11.87)], which were obviously higher than the control group, and there was statistical significance. The results of survey showed that the students thought the teaching mode aroused their study interests while 393 (93.7%), thought the teaching mode developed their self-study ability while 357 (89.7%), thought the teaching mode beneficial to cultivating their ability of solving the problems. Conclusion The teaching mode of technological pedagogical and content knowledge is of certain signifi-cance to break the plight of the traditional teaching, inspire the students interest in learning, improve the teaching quality of biochemistry, and make for the teachers' professional development.