[Establishment of acute graft-versus-host disease model after non-myeloablative haploidentical peripheral blood stem cell transplantation in aged mice].

Objective: To establish an acute graft-versus-host disease (aGVHD) model in aged mice after non-myeloablative haploidentical peripheral blood stem cell transplantation (haplo-PSCT). Methods: C57BL/6 (H-2b) male mice aged 6-8 weeks were used as donor mice, and CB6F1 (H-2b×d) female mice aged 14-16 months were used as recipient mice. The donor mice were injected subcutaneously with rehuman granulocyte-colony stimulating factor (rhG-CSF) 5 days before transplantation for hematopoietic stem cell mobilization.The recipient mice were divided into control group (CG), spleen cell low-dose group (SL), spleen cell medium-dose group (SM) and spleen cell high-dose group (SH) according to random number table method, with 16 rats in each group, all of which received total linear accelerator X-ray irradiation (TBI) with a total dose of 6 Gy. Peripheral blood mononuclear cells (PBMC) and spleen cells of different doses (0.5×107/each, 1.0×107/each and 2.0×107/each in SL group, SM group and SH group, respectively) were transfused through the tail vein within 4 hours after TBI, and only the same amount of normal saline was transfused in CG group. After transplantation, the survival and weight changes of mice in each group were observed for 30 days, and the changes of blood routine were monitored regularly. Mice peripheral blood was collected 21 days after transplantation to detect the chimerism rate of the donor. Hematoxylin-eosin staining was performed on the skin, liver and colon of mice 21 days after transplantation to analyze the histopathological changes of aGVHD target organs. Results: All the mice in each group were successfully transplanted. After TBI, the weight and activity of mice in all groups decreased, and the phenomenon of bone marrow suppression appeared. During the observation period, all mice in CG group and SL group survived, 3 mice in SM group died with survival time of (26.0±5.8) days, and 6 mice in SH group died with survival time of (20.9±7.3) days. The body weight of mice in SH group was lower than that in CG group, SL group and SM group 21days after transplantation [(25.0±0.7), (25.5±0.4), (25.0±1.4) vs (20.8±0.8) g, all P<0.05]. Compared with CG group, SL group and SM group, the levels of leukocyte, erythrocyte, hemoglobin and platelet in SH group decreased 21 days after transplantation (all P<0.05). There was no significant difference in donor chimerism rate among SL group, SM group and SH group [(95.8%±0.8%), (95.5%±1.4%) and (95.1%±1.3%), respectively, all P>0.05]. Compared with CG group, SL group and SM group, the tissue structure of aGVHD target organs in SH group was severely damaged, with a large number of inflammatory cells infiltratedand higher histopathological scores than SL group and SM group (all P<0.05). Conclusion: For aging CB6F1 mice, after 6 Gy TBI pretreatment with linear accelerator X-ray, PBMC (1×107/each) and spleen cells (2.0×107/each) were injected to successfully induce aGVHD model after non-myelablative haplo-PSCT.

[17-year study on the curative effect of treatment to prevent the recurrence of hepatitis B in different risk groups after liver transplantation].

Objective: To observe the recurrence condition of hepatitis B in different risk groups after liver transplantation in an attempt to provide useful information on whether to discontinue hepatitis B immunoglobulin (HBIG) in the future at an early stage. Methods: The patient population was divided into high, low-risk, and special groups [especially primary hepatocellular carcinoma (HCC)] according to the guidelines for the prevention and treatment of hepatitis B recurrence after liver transplantation. The recurrence condition and risk factors in this population were observed for hepatitis B. Measurement data were analyzed using a t-test and a rank-sum test. Count data were compared using a χ(2) test between groups. Results: This study finally included 532 hepatitis B-related liver transplant cases. A total of 35 cases had HBV recurrence after liver transplantation, including 34 cases that were HBsAg positive, one case that was HBsAg negative, and 10 cases that were hepatitis B virus (HBV) DNA positive. The overall HBV recurrence rate was 6.6%. The recurrence rate of HBV was 9.2% and 4.8% in the high- and low-risk HBV DNA positive and negative groups before surgery (P = 0.057). Among the 293 cases diagnosed with HCC before liver transplantation, 30 had hepatitis B recurrence after surgery, with a recurrence rate of 10.2%. The independent related factors for the recurrence of hepatitis B in patients with HCC after liver transplantation were HCC recurrence (HR =181.92, 95%CI 15.99~2 069.96, P < 0.001), a high postoperative dose of mycophenolate mofetil dispersible tablets (MMF) ( HR =5.190, 95%CI 1.289~20.889, P = 0.020), and a high dosage of HBIG (HR = 1.012, 95%CI 1.001~1.023, P = 0.035). Among the 239 cases who were non-HCC before liver transplantation, five cases (recurrence rate of 2.1%) arouse postoperative hepatitis B recurrence. Lamivudine was used in all cases, combined with on-demand HBIG prophylaxis after surgery. There was no hepatitis B recurrence in non-HCC patients who treated with entecavir combined with HBIG after surgery. Conclusion: High-barrier-to-resistance nucleotide analogues combined with long-term HBIG have a good effect on preventing the recurrence of hepatitis B after liver transplantation. The discontinuation of HBIG may be considered at an early stage after administration of a high-barrier-to-resistance nucleotide analogue in low-risk patients. Domestically, the HBV infection rate is high, so further research is still required to explore the timing of HBIG discontinuation for high-risk patients, especially those with HCC.

A randomised controlled trial of dexmedetomidine for delirium in adults undergoing heart valve surgery.

Dexmedetomidine might reduce delirium after cardiac surgery. We allocated 326 participants to an infusion of dexmedetomidine at a rate of 0.6 µg kg-1 for 10 min and then at 0.4 µg.kg-1 .h-1 until the end of surgery; 326 control participants received comparable volumes of saline. We detected delirium in 98/652 (15%) participants during the first seven postoperative days: 47/326 after dexmedetomidine vs. 51/326 after placebo, p = 0.62, adjusted relative risk (95%CI) 0.86 (0.56-1.33), p = 0.51. Postoperative renal impairment (Kidney Disease Improving Global Outcomes stages 1, 2 and 3) was detected in 46, 9 and 2 participants after dexmedetomidine and 25, 7 and 4 control participants, p = 0.040. Intra-operative dexmedetomidine infusion did not reduce the incidence of delirium after cardiac valve surgery but might impair renal function.

[A real-world study on the efficacy and safety analysis of paclitaxel liposome in advanced breast cancer].

Objective: To explore the application and efficacy of paclitaxel liposome in the treatment of advanced breast cancer among Chinese population in the real world. Methods: The clinical characteristics of patients with advanced breast cancer who received paclitaxel liposome as salvage treatment from January 1, 2016 to August 31, 2019 in 11 hospitals were collected and retrospectively analyzed. The primary outcome was progression free survival (PFS), and the secondary outcome included objective response rate (ORR) and safety. The survival curve was drawn by Kaplan-Meier analysis and the Cox regression model were used for the multivariate analysis. Results: Among 647 patients with advanced breast cancer who received paclitaxel liposome, the first-line treatment accounted for 43.3% (280/647), the second-line treatment accounted for 27.7% (179/647), and the third-line and above treatment accounted for 29.1% (188/647). The median dose of first-line and second-line treatment was 260 mg per cycle, and 240 mg in third line and above treatment. The median period of paclitaxel liposome alone and combined chemotherapy or targeted therapy is 4 cycles and 6 cycles, respectively. In the whole group, 167 patients (25.8%) were treated with paclitaxel liposome combined with capecitabine±trastuzumab (TX±H), 123 patients (19.0%) were treated with paclitaxel liposome alone (T), and 119 patients (18.4%) were treated with paclitaxel liposome combined with platinum ± trastuzumab (TP±H), 108 patients (16.7%) were treated with paclitaxel liposome combined with trastuzumab ± pertuzumab (TH±P). The median PFS of first-line and second-line patients (5.5 and 5.5 months, respectively) were longer than that of patients treated with third line and above (4.9 months, P<0.05); The ORR of the first line, second line, third line and above patients were 46.7%, 36.8% and 28.2%, respectively. Multivariate analysis showed that event-free survival (EFS) and the number of treatment lines were independent prognostic factors for PFS. The common adverse events were myelosuppression, gastrointestinal reactions, hand foot syndrome and abnormal liver function. Conclusion: Paclitaxel liposomes is widely used and has promising efficacy in multi-subtype advanced breast cancer.

[Establishment and validation of a nomogram-based predictive model for idiopathic aldosteronism].

Objective: To establish and validate a nomogram-based predictive model for idiopathic hyperaldosteronism (IHA). Methods: This cross-sectional study was conducted with the collected clinical and biochemical data of patients with primary aldosteronism (PA) including 249 patients with unilateral primary aldosteronism (UPA) and 107 patients with IHA, who were treated at the Department of Endocrinology of the First Affiliated Hospital of Chongqing Medical University from November 2013 to November 2022. Plasma aldosterone concentration (PAC) and plasma renin concentration (PRC) were measured by chemiluminescence. Stepwise regression analysis was applied to select the key predictors of IHA, and a nomogram-based scoring model was developed. The model was validated in another external independent cohort of patients with PA including 62 patients with UPA and 43 patients with IHA, who were diagnosed at the Department of Endocrinology, First Affiliated Hospital of Zhengzhou University. An independent-sample t test, Mann-Whitney U test, and χ2 test were used for statistical analysis. Results: In the training cohort, in comparison with the UPA group, the IHA group showed a higher serum potassium level [M(Q1, Q3), 3.4 (3.1, 3.8) mmol/L vs. 2.7 (2.1, 3.1) mmol/L] and higher PRC [4.0 (2.1, 8.2) mU/L vs. 1.5 (0.6, 3.4) mU/L] and a lower PAC post-saline infusion test (SIT) [305 (222, 416) pmol/L vs. 720 (443, 1 136) pmol/L] and a lower rate of unilateral adrenal nodules [33.6% (36/107) vs. 81.1% (202/249)]; the intergroup differences in these measurements were statistically significant (all P<0.001). Serum potassium level, PRC, PAC post-SIT, and the rate of unilateral adrenal nodules showed similar performance in the IHA group in the validation cohort. After stepwise regression analysis for all significant variables in the training cohort, a scoring model based on a nomogram was constructed, and the predictive parameters included the rate of unilateral adrenal nodules, serum potassium concentration, PAC post-SIT, and PRC in the standing position. When the total score was ≥14, the model showed a sensitivity of 0.65 and specificity of 0.90 in the training cohort and a sensitivity of 0.56 and specificity of 1.00 in the validation cohort. Conclusion: The nomogram was used to successfully develop a model for prediction of IHA that could facilitate selection of patients with IHA who required medication directly.

[The relationship between the characteristics of tears and the progression of Stanford type B aortic dissection after endovascular treatment].

Endovascular treatment of Stanford type B aortic dissection (type B dissection) has been widely used. There will be complications such as aortic dilatation, which will lead to poor prognosis of some patients. With more in-depth researches, it was found that there was a possible correlation between the prognosis of type B dissection and tears, such as the increasing of aortic diameter would be faster with longer tears, and the location of the tear will affect the thrombosis of the false lumen. Studies on hemodynamics have also found that different characteristics of tears of aortic dissection can cause changes in the pressure, blood flow rate and blood capacity in the true and false lumens recently. The hemodynamic changes can be used to predict the prognosis of type B dissection. The main characteristics of tears included the size, position, number of tears, residual tears and stent graft induced new entry. Describing the effect of tear characteristics on the development of type B dissection, can provide the basis for the clinical treatment and further research of type B dissection.

Limonitum Ameliorates Castor Oil-Induced Diarrhoea in Mice by Modulating Gut Microbiota.

Diarrhoea is a common clinical condition; its pathogenesis is strongly associated with gut microbiota dysbiosis. Limonitum is a well-known traditional Chinese medicine that exerts appreciable benefits regarding the amelioration of diarrhoea. However, the mechanism through which Limonitum ameliorates diarrhoea remains unclear. Here, the efficacy and underlying mechanism of Limonitum decoction (LD) regarding diarrhoea were explored from the aspect of gut microbiota. Castor oil (CO) was used to induce diarrhoea in mice, which were then used to evaluate the effects of LD regarding the timing of the first defecation, diarrhoea stool rate, degree of diarrhoea, diarrhoea score, intestinal propulsive rate, and weight of intestinal contents. The concentrations of short-chain fatty acids (SCFAs), including acetic, propionic, isobutyric, butyric and valeric acids, were analysed by gas chromatography-mass spectrometry (GC-MS). The 16S rRNA high-throughput sequencing technology was applied to evaluate changes in the gut microbiota under exposure to LD. LD was found to effectively ameliorate the symptoms of diarrhoea, and the diversity and relative abundance of gut microbiota were restored to normal levels following LD treatment. Additionally, LD significantly restored the observed reductions in SCFAs. These results provide strong evidence that LD can sufficiently ameliorate diarrhoea in mice by regulating their gut microbiota. The findings presented here highlight that Limonitum may constitute a prospective remedy for diarrhoea.

[Effect factors of collateral blood supply of patients with early trimester cesarean scar pregnancy].

Objective: To investigate the characteristics and effect factors of collateral blood supply of patients with early trimester cesarean scar pregnancy(CSP). Methods: This study was a multicenter case-control study, with 219 inpatients with CSP in First People's Hospital of Zhengzhou, Zhengzhou Central Hospital, Third People's Hospital of Zhengzhou and Henan No3 Provincial People's Hospital from January 1, 2017 to June 30, 2020 who were selected to obtain their clinical data. Double-blind method was performed in digital subtraction angiography imaging analysis. The patients were divided into collateral blood supply group and non-collateral blood supply group, and the incidence of collateral blood supply of patients with early trimester CSP was calculated. Multivariate binary logistic regression analysis was performed to find the independent risk factors of collateral blood supply of patients with early trimester CSP. As well, clinical outcomes after uterine artery embolization (UAE) were compared between the two groups. Results: A total of 219 patients with early trimester CSP have average age of (32.4±5.0) years old and average pregnancy of (51.0±10.6) days. The incidence of collateral blood supply was 12.3% (27 cases), of which16 cases were on the left, 6 on the right and 5 in both sides. A total of 43 collateral vessels were found, with 1.59 vessels per patient on average. Bladder artery was the most common source of collateral blood supply, accounting for 74.4% (32/43), followed by internal pudendal artery for 18.6% (8/43). Multivariate binary logistic regression analysis showed that gestational weeks ≥8 weeks, maximum diameter of gestational sac ≥50 mm and rich blood supply of gestational sac are independent risk factors for collateral blood supply of patients with early trimester CSP, with OR (95%CI) 3.68 (1.06-12.76), 7.00 (1.52-32.19)、9.96 (3.59-27.58), respectively, all P<0.05. The success rates of UAE were 100% in both groups. The reduction in serum ß-Human chorionic gonadotropin (ß-HCG) level at 24 hours after UAE, vaginal bleeding during uterine curettage, hysterectomy and menstrual recovery time were not found to have significant difference between groups (all P>0.05). Conclusions: Early trimester CSP leads to a certain occurrence of collateral blood supply, which may have adverse impact on the efficacy of UAE and patient safety. Gestational weeks, the maximum diameter of gestational sac and the degree of vascularization of gestation sac have certain value in suggesting the collateral blood supply of patients with early trimester CSP, which is helpful for the complete embolization of gestational sac in the process of UAE.

[Establishment and validation of prediction model of new-onset pelvic organ prolapse in early postpartum period].

Objective: To analyze the risk factors of pelvic organ prolapse (POP) and to establish the prediction model. Methods: A study was conducted on the prevalence of POP among 2 247 parturient women at 6 weeks postpartum in Peking University People's Hospital from December 2018 to October 2019, and relevant influencing factors were analyzed to construct a prediction model of early postpartum POP using logsitic regression, which was validated internally. Data from November 2019 to December 2019 (403 parturient women) were collected for external validation of the prediction model. In addition, the obstetrical factors affecting the occurrence of early postpartum POP in 885 primiparas with vaginal delivery (from January 2019 to November 2019) were further discussed. Results: A total of 2 247 cases were included in the modeling group, and 403 cases were included in the external validation data set. POP accounted for 24.3% (545/2 247). Age, parity, body mass index before pregnancy, vaginal delivery and newborn birth weight were negative factors for early postpartum POP (all P<0.05). The nomogram was established based on the above factors, and internal and external verification indicated that the model had a good discrimination (C-index were 0.759 and 0.760, respectively). In addition, this study found that age and newborn birth weight were the main causes of early postpartum POP in primiparas with vaginal delivery (P=0.044, P=0.004). Conclusions: The incidence of early postpartum POP is high. The prediction model of POP constructed in this study could be used to guide clinical practice to a certain extent and give corresponding treatment suggestions to pregnant women scientifically, so as to provide theoretical support for primary prevention.

[Research progress of mesenchymal stem cells in female reproductive medicine].

Stem cells have been a hot spot in medical research for a long time and have unique advantages in tissue repair, diagnosis and treatment of diseases. With the development of regenerative medicine, stem cells have been widely studied and applied in reproductive medicine, such as improving ovarian function and repairing endometrial damage. These efforts are achieved primarily through the use of mesenchymal stem cells(MSCs) from a variety of sources. However, the application of stem cells also faces problems such as low cell retention rate and medical ethics. This article focuses on the research progress and clinical application of MSCs (not involving embryonic stem cells) in the field of female reproductive medicine.

Current status and distribution of hip fractures among older adults in China.

China is a middle-risk country for hip fracture at present, which differs from previous data that it was low-risk. By 2050, the total number of hip fractures in people older than 65 years is predicted to be 1.3 million. INTRODUCTION: To assess hip fracture incidence in China and examine the heterogeneity of hip fracture in seven geographical regions of China. METHODS: There were 238,230 hip fracture patients aged 65 years or older from 2013 to 2016 from a large national in-patients database (HQMS) involving 30.6 million hospitalizations. Taking into account the total national hospitalization rate per calendar year, we estimated the incidence of hip fracture per 100,000 residents older than 65 years in China overall and in seven geographical Chinese regions. RESULTS: The proportion of men and women older than 65 years with hip fractures was 1.00:1.95. Between 2013 and 2016, the number of hip fractures per 100,000 people age 65+ was 278. China has vast territories; the number of hip fractures per 100,000 people over 65 years old was 202 in Northeast China and 374 in Northwest China. Northwest has higher altitude, lower population density, is less developed with lower urbanization than Northeast China which is low altitude, and highly urbanized. CONCLUSIONS: China should no longer be regarded as a low-risk country for hip fracture. By 2050, the total number of hip fractures in people older than 65 years in China is predicted to be 1.3 million. Higher altitude areas had higher hip fracture rates than lower altitude, higher urbanized areas.

Diagnostic value of maximum signal intensity on T1-weighted MRI images for differentiating parotid gland tumours along with pathological correlation.

AIM: To investigate the efficacy of the maximum signal intensity of tumour on T1-weighted magnetic resonance imaging (MRI) images for differentiating Warthin's tumours (WTs) from pleomorphic adenomas (PAs) and malignant tumours (MTs). MATERIALS AND METHODS: One hundred and fifty-four histopathologically confirmed parotid tumours, including 76 PAs, 45 WTs, and 33 MTs, were analysed. MRI results were compared with pathological findings. The maximum signal intensity of tumour and the average signal intensity of spinal cord were measured on T1-weighted images, then the tumour-to-spinal cord signal intensity ratio (T1-max-SIR) was calculated. The distribution of T1-max-SIRs among the three groups of tumours was analysed using the Mann-Whitney U-test. Receiver operating characteristic curves were generated to assess the ability of T1-max-SIRs to differentiate parotid tumours. In addition, the interobserver agreement between readers was assessed using interclass correlation coefficient (ICC). RESULTS: T1-max-SIRs were higher in WTs than in PAs (p<0.001) and MTs (p<0.001), and no significant difference was found between PAs and MTs (p=0.151). The area under the curve (AUC) of T1-max-SIRs for differentiating WTs from PAs was 0.901, with a sensitivity of 91.1% and a specificity of 82.9%. The AUC of T1-max-SIRs for differentiating WTs from MTs was 0.851, with a sensitivity of 88.9% and a specificity of 78.8%. Readers had excellent interobserver agreement on T1-max-SIRs (ICC = 0.989; 95% confidence interval, 0.985-0.992). CONCLUSIONS: T1-max-SIRs can be useful for differentiating WTs from PAs and MTs with high diagnostic efficiency.

[Triptolide increases the radiosensitivity of lung cancer cells by inhibiting DNA repair and inducing apoptosis].

Objective: To investigate the effect of triptolide on radiosensitivity of lung cancer cells and its mechanism. Methods: The lung cancer cells H1299, A549, H157 and H838 were cultured. The strongest radio resistance cell line, H1299 was selected by cell clone formation experiment and for the subsequent experiments. 3-(4, 5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2H tetrazolium bromide (MTT) was used to detect the effect of different concentrations of triptolide on the proliferation of H1299 cells. The optimal concentration of triptolide was 50nmol/L, and the optimal treatment time was 48 hours. The H1299 cells were divided into the control group, triptolide group (50 nmol/L), 4 Gy group and triptolide+ 4 Gy group. Flow cytometry was used to detect the apoptosis rate of H1299 cell. Western Blot was used to detect the proteins expression levels of p-Chk2, p-ATM, p-p53, Bcl-2, Bax and cleaved-Caspase 3. Results: The apoptotic rate and protein levels of Bax, cleaved-Caspase 3, p-Chk2, p-ATM and p-p53 in the 4 Gy group were (12.38±1.34)%, 0.42±0.04, 0.38±0.04, 0.98±0.11, 0.73±0.08, 0.95±0.09, respectively, higher than (3.26±2.43)%, 0.22±0.02, 0.23±0.03, 0.32±0.03, 0.21±0.02, 0.25±0.03 in the control group (P<0.05). However, the protein level of Bcl-2 was (0.52±0.05), lower than (0.93±0.09) of the control group (P<0.05). The survival fraction (0.462) and protein level of Bcl-2 (0.44±0.04) in the triptolide group were lower than those of the control group (0.702 and 0.93±0.09, P<0.05). The apoptotic rate and the protein levels of Bax and cleaved-Caspase 3 in the triptolide group were (9.27±1.08)%, 0.45±0.05, 0.41±0.04, respectively, higher than (3.26±2.43)%, 0.22±0.02, 0.23±0.03 in the control group (P<0.05), and the sensitization ratio in the triptolide group was 1.579. The apoptosis rate, Bax and cleaved Caspase 3 protein expression levels in triptolide + 4 Gy group were (26.53±2.19)%, 0.91±0.09 and 0.79±0.08, respectively, higher than (12.38±1.34)%, 0.42±0.04 and 0.38±0.04 in 4 Gy group (P<0.05). The expression level of Bcl-2 protein was (0.21±0.02), lower than (0.52±0.05) in 4 Gy group (P<0.05). Conclusion: Triptolide increases the radiosensitivity of radiation-induced lung cancer cells by inhibiting DNA repair and inducing apoptosis.

[Effect of posterior tibial slope on the short-term outcome in mobile-bearing unicompartmental knee arthroplasty].

OBJECTIVE: To evaluate the relationship between postoperative knee function and the sagittal position of tibial component in unicompartmental knee arthroplasty (UKA). METHODS: We retrospectively enrolled the patients who underwent UKA from January 2016 to May 2020. They were assigned into 2 groups according to postoperative posterior tibial slope (PTS): the normal PTS group (PTS≥3° and PTS < 8°) and the abnormal PTS group (PTS < 3° or ≥8°). The patients were followed up for at least 12 months. The postoperative Knee Society Clinical Score (KSS-C), Knee Society Functional Score (KSS-F) and knee range of motion (ROM) were compared between the two groups. RESULTS: A total of 72 patients (82 knees) were included with 51 patients (58 knees) in PTS normal group and 21 patients (24 knees) in PTS abnormal group. All the patients were followed up with median of 23.6 months. There was no significant difference in the general data [gender, age, body mass index (BMI)], pre-operative knee range of motion, preoperative KSS-C score and KSS-F score (P > 0.01). The KSS-C score, KSS-F score, and knee range of motion significantly improved after surgery (P < 0.01) for all the patients. The postoperative KSS-C score in normal PTS group (88.76±2.79) was significantly higher than the KSS-C score in abnormal PTS group (84.42±3.35, P < 0.01), but no significant difference between the 2 groups was observed in postoperative KSS-F score and knee range of motion (P > 0.01). In addition, there was no correlation between the change of PTS and postoperative KSS-C score (r=-0.034, 95%CI: -0.247 to 0.186, P = 0.759), KSS-F score (r = -0.014, 95%CI: -0.238 to 0.198, P = 0.901) and knee range of motion (r= 0.045, 95%CI: -0.214 to 0.302, P = 0.686). CONCLUSION: The posterior tibial slope between 3° and < 8° can be recommended to improve knee joint function in mobile UKA, and excessive or insufficient PTS should be avoided.

[Effects of neuromuscular exercise therapy on the joint stability of patients with knee osteoarthritis].

Objective: To evaluate the effects of neuromuscular exercise therapy on joint stability of knee osteoarthritis (OA) patients. Methods: One hundred and ten patients with knee OA were enrolled in this ongoing prospective cohort study at Arthritis Clinic and Research Center, Peking University People's Hospital from September 2017 to October 2018. The treatment consisted of six-week neuromuscular exercise therapy. The participants were followed up at 6 weeks and 3 months after the therapy. The stability of the joint was evaluated by the index of knee joint stability (IKJS), which was extracted by a novel knee-aiming task combined with the multiscale entropy (MSE) analysis of the complexity of the light spot trajectories. The secondary outcomes were pain on the visual analogue scale (VAS, 0-100), the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), quality of life on the Euro-quality of life-5 Dimensional (EQ-5D) VAS form, 30-second chair stand test and 40-meter walk test. One-way repeated measures ANOVA analysis was applied to compare the outcomes at baseline and 6 weeks and 3 months. Pearson partial analysis was used to investigate the correlation between the IKJS and the Kellgren-Lawrence (K/L) rate, pain and knee function. Results: Ninety-six participants ((65±8) years, 21 males, 75 females) completed 3-month follow-up. There was a significant improvement in IKJS at the 6-week visit compared with that at baseline (0.369, 95% confidence interval (CI) 0.241-0.496, P<0.001). The IKJS dropped at 3-month visit compared with 6-week visit, but was still better than that at baseline (0.178, 95%CI: 0.042-0.314, P=0.008). The correlation between IKJS and K/L rate, severity of pain, WOMAC or knee function was not significant (r=-0.131, -0.059, -0.231, 0.124, all P>0.05). There was improvement in pain VAS, WOMAC, EQ-5D-VAS, 30-second chair stand test and 40-meter walk test at 6 weeks and 3 months (all P<0.05). Conclusion: The neuromuscular exercise therapy is effective in improving the joint stability of the knee OA patients. However, the effect gradually diminished over time. In addition, neuromuscular exercise can help relieve pain, improve the function and quality of life in patients with knee OA.

[Biocompatibility of extracellular matrix hydrogel with human iPSCs differentiated cardiomyocytes].

Objective: To observe the biocompatibility of porcine omental derived extracellular matrix (ECM) hydrogel with human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) and the feasibility of ECM hydrogel as a delivery vector of cell transplantation. Methods: A series of chemical, physical and enzymatic methods were applied to acellularize the porcine omentum. Subsequently, the extracted ECM was prepared into thermosensitive hydrogel. The biochemical composition of the hydrogel was identified by histological staining. The microstructure was observed by scanning electron microscopy. The hydrogel was then injected into the myocardium of mice to observe its in situ gelation ability. Differentiation of human induced pluripotent stem cells into cardiomyocytes was achieved by small molecule induction, and then the obtained hiPSC-CMs were cultured. hiPSC-CMs cultured onto the prepared hydrogel were defined as the hydrogel group, while conventionally cultured hiPSC-CMs were defined as the control group. Cardiomyocyte viability and growth patterns were detected using live/dead staining, CCK-8 and phalloidin staining. Immunofluorescence staining and Western blot of cardiomyocytes were used to determine the survival and phenotypic maintenance markers of cardiomyocytes in materials. Results: The results of HE staining, oil red O staining and DAPI fluorescence staining showed that there was no significant cell debris, nucleus and lipid residue in the prepared ECM hydrogel. The Sirius red staining and Alcian blue staining showed that the hydrogel retained collagen and glycolaminoglycan, which were the main components of ECM. The prepared hydrogel behaves as a viscous liquid at 4 ℃ and as a gel state at 37 ℃. Scanning electron microscope results showed that the microstructure of the hydrogel was composed of irregular fibers and pores of different sizes. Under the guidance of ultrasound, the prepared ECM hydrogel could be successfully injected into the myocardium of mice. Immediately after the injection, the hyperechoic signal could be observed under ultrasound, suggesting that the hydrogel remained in the myocardium. HE staining of myocardial tissue evidenced that there was lump of gel in the injection area. The differentiated hiPSC-CMs were co-cultured with the prepared ECM hydrogel, and the results of live/dead staining showed that most of the hiPSC-CMs in the hydrogel group and the control group were alive, dead cells were scanty. The results of CCK-8 test showed that the absorbance values of the two groups were similar (P>0.05). The results of phalloidin staining showed that hiPSC-CMs could extend normally when co-cultured with ECM hydrogel. The cell morphology of the hydrogel group was similar with that of the control group, and there was no statistically significant difference in the F-actin coverage area per cell between the two groups (P>0.05). Immunofluorescence staining of cardiomyocyte markers showed that there was no significant difference in the coverage area of α-actinin and connexin-43 (Cx-43) per field between the hydrogel group and the control group (both P>0.05), the quantitative results of DAPI staining showed that there was no statistically significant difference in the number of cells between the two groups (P>0.05). Meanwhile, the results of Western blot showed that the expression levels of α-actinin and Cx-43 in cardiomyocytes in the hydrogel group were similar as those in the control group (both P>0.05). Conclusions: These results show that preparation of the ECM hydrogel from porcine omentum is successful. The hydrogel has good biocompatibility and no obvious cytotoxicity. Besides, the hydrogel can support the survival of hiPSC-CMs in vitro and maintain its phenotype. These properties make it a promising injectable cardiac tissue engineering material.

Aerosol and environmental surface monitoring for SARS-CoV-2 RNA in a designated hospital for severe COVID-19 patients.

There is limited information concerning the viral load of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in aerosols deposited on environmental surfaces and the effectiveness of infection prevention and control procedures on eliminating SARS-CoV-2 contamination in hospital settings. We examined the concentration of SARS-CoV-2 in aerosol samples and on environmental surfaces in a hospital designated for treating severe COVID-19 patients. Aerosol samples were collected by a microbial air sampler, and environmental surfaces were sampled using sterile premoistened swabs at multiple sites. Ninety surface swabs and 135 aerosol samples were collected. Only two swabs, sampled from the inside of a patient's mask, were positive for SARS-CoV-2 RNA. All other swabs and aerosol samples were negative for the virus. Our study indicated that strict implementation of infection prevention and control procedures was highly effective in eliminating aerosol and environmental borne SARS-CoV-2 RNA thereby reducing the risk of cross-infection in hospitals.

[Transurethral seminal vesiculoscopy in treatment of oligoasthenozoospermia secondary incomplete ejaculatory duct obstruction: A report of 8 cases].

OBJECTIVE: To evaluate the utility of transurethral seminal vesiculoscopy with a slender ureteroscope in the treatment of severe oligoasthenozoospermia secondary incomplete ejaculatory duct obstruction (EDO). METHODS: From March 2018 to September 2018, the clinical data of 8 patients with severe oligoasthenozoospermia secondary incomplete EDO treated by the technique of transurethral seminal vesiculoscopy in the Peking University Third Hospital Reproductive Center were analyzed. Preoperative routine included semen analysis, hormone determination, transrectal ultrasonography, pelvic magne-tic resonance examination and other examinations. All the patients were diagnosed with severe oligoasthenozoospermia secondary to incomplete EDO. All the patients were operated by the same surgeon with multiple cases of experience in transurethral surgery, and 1 year follow-up was conducted to evaluate the surgical effect. RESULTS: The average age of the 8 patients was 29 years, and the average operation time was 32 min. Preoperative transrectal ultrasound indicated 6 cases of ejaculatory duct cyst or Mullerian cyst, 1 case of prostate calcification and bilateral seminal vesicle dilatation. The average maximum transverse diameter of the right seminal vesicle in pelvic MRI was 33.60 mm (24.63-42.28 mm), the average maximum transverse diameter of the left seminal vesicle was 32.85 mm (25.91-44.89 mm), the ave-rage maximum antero-posterior diameter was 27.99 mm (21.36-33.12 mm), the average maximum width of the seminal vesicle duct was 10.53 mm (5.93-19.39 mm). There were 5 cases of ejaculatory duct cyst, 2 cases of seminal vesicle hemorrhage, and 1 case of Mullerian cyst. The semen volume [(2.64±0.80) mL], the sperm concentration [(49.76±8.50)×106/mL], and the motility (grade a+b) [(25.76±6.48)%] in postoperation were significantly higher than those in preoperation [(1.46±0.50) mL, (28.78±5.17)×106/mL, and (2.88±0.93)%, P < 0.05]. Two patients conceived naturally during the follow-up of 6 months after surgery. There were no severe complications, such as retrograde ejaculation, urinary incontinence or rectal injury. CONCLUSION: The technique of transurethral seminal vesiculoscopy is safe and effective for treating severe oligoasthenozoospermia secondary to incomplete EDO. However, due to the small sample size of this study, short follow-up time, and the uncertainty in seminal vesicle surgery, it still needs to be further confirmed by long-term follow-up studies with large samples.

[Effects of Prrx2 gene silencing on the proliferation of breast cancer and its molecular mechanisms].

Objective: The aim of this study was to investigate the effects of silencing Paired related homoeobox 2 (Prrx2) expression on the proliferation of breast cancer and its molecular mechanisms. Methods: Short hairpin RNA knockdown of Prrx2 was used to examine cellular effects of Prrx2. The level of Prrx2 was verified by Western blot. MTT assay was used to analyze the proliferation of breast cancer cells in vitro. To investigate the effect of Prrx2 depletion on tumor growth in vivo, a nude mouse xenograft model was performed. Results: The expression of Prrx2 decreased 91.2% in MDA-MB-231 cells and 88.7% in MCF-7 cells after transfection with interfering vectors (P<0.05). MTT assay showed that the proliferation of cells in silenced Prrx2 expression group was significantly inhibited compared with the control group (P<0.05). Nude mice transplanted tumors showed that the growth of transplanted tumors was slow after silencing Prrx2 expression, and the weight of the tumors of silenced Prrx2 expression group were smaller than those of the control group ((160.2±26.3)mg vs (365.4±19.7)mg, P<0.05). Western blot showed that silencing Prrx2 expression inhibited the expression of ß-catenin in breast cancer cell nucleus and down-regulated the activity of Wnt/ß-catenin signaling pathway. Conclusions: Silencing Prrx2 expression can effectively inhibit the proliferation and growth of breast cancer, suggesting that Prrx2 may become a new target for the treatment of breast cancer.

[Meta-analysis on tetanus antibody protection rate of healthy population born after 1978 in China].

Objective: Meta-analysis was conducted on the tetanus antibody protection rate of healthy population born after 1978 in China (data from Hong Kong, Macao and Taiwan was excluded, the same below). Methods: Search the data on China's tetanus antibody level which were published in China National Knowledge Infrastructure, Wanfang data, VIP, SinoMed database, PubMed and the Cochrane Library. The Chinese search keywords were "Tetanus Antitoxin", "Tetanus Antibody", "Healthy Population" and "Mainland China". English search terms include "tetanus antitoxin", "tetanus vaccine", "tetanus vaccine", "general population" and "mainland of China". The time limit for inclusion in literature research was 2010-2019. Stata software was used to conduct meta-analysis on the protection rate of tetanus antibody. Results: A total of 24 articles were included. There was no obvious publication bias in the included articles. The total number of respondents was 23 530, the antibody protection rate was 49.5%-99.0%. A total of 20 817 people got effective antibody protection, which meant the antibody level reached and exceeded 0.1 IU/ml, and the combined protection rate was 78.6% (95%CI: 75.0%-88.2%). The combined protection rates of antibody in 0-7 years old and 8-15 years old groups were 88.9% (95%CI: 86.9%-91.0%) and 79.3% (95%CI: 72.9%-86.2%) respectively. The combined protection rates of antibodies in 16-20 years old, 21-30 years old and 31-40 years old groups were 58.9% (95%CI: 46.5%-71.2%), 47.7% (95%CI: 16.8%-78.7%) and 63.8% (95%CI:32.6%-95.1%) respectively. The combined protection rate of tetanus antibody for 0-15 years old people was 85.6% (95%CI: 83.1%-88.1%), and the combined protection rate of antibody for 16-40 years old people was 52.9% (95%CI: 39.3%-66.6%). Conclusion: With the increase of age, the protection rate of tetanus antibody among the healthy population aged 16-40 years in our country decreases. An individualized vaccination plan should be formulated according to the previous tetanus vaccination history and the tetanus antibody level when necessary.