Objective:To discuss the effect of exosome(Exo)microRNA-761(miR-761)on the epithelial-mesenchymal transition(EMT)process of the osteosarcoma(OS)cells by regulating tumor-associated macrophage(TAM)polarization,and to clarify its related mechanism.Methods:The miR-761 plasmid and negative control(miR-NC)plasmid were transfected into the HEK293 cells,and the non-transfected cells were regarded as control group.The transfection efficiency was detected using real-time fluorescence quantitative PCR(RT-qPCR)method.The Exo containing miR-761 was isolated,and the morphology of Exo was observed by transmission electron microscope.The concentration and size distribution of Exo samples were detected by nanoparticle analyzer,and the expression of Exo surface marker protein was detected by Western blotting method.The human monocyte leukemia THP-1 cells were stimulated with phorbol 12-myristate 13-acetate(PMA)to become the M0 macrophages,which were then treated with Exo containing miR-761 and co-cultured with the OS MG63 cells to establish the co-culture system.The experiment was divided into M0 group,TAM group,miR-761 NC group,and miR-761 Exo group.The M0 macrophages were collected from various groups,and the positive rates of M1 macrophage marker CD86 and M2 macrophage marker CD206 in various groups were detected by flow cytometry;the protein expression levels of M1 macrophage secreted factors interleukin-1β(IL-1β)and tumor necrosis factor-α(TNF-α)and M2 macrophage secreted factors interleukin-10(IL-10)and transforming growth factor-β1(TGF-β1)in various groups were detected by Western blotting method.The M0 macrophages were treated with Exo containing miR-761 and co-cultured with MG63 cells to establish the co-culture system.The experiment was divided into control group,TAM group,miR-NC Exo+TAM group,and miR-761 Exo+TAM group.The MG63 cells in various groups were collected,and the fluorescence intensities of E-cadherin and Vimentin in the MG63 cells in various groups were observed by immunofluorescence staining;the expression levels of E-cadherin,Vimentin,and EMT regulation-related transcription factors Twist1,Snail,and Slug proteins in the cells in various groups were detected by Western blotting method;the numbers of invasion and migration cells in various groups were detected by Transwell chamber assay.Results:The HEK293 cells containing miR-761 were successfully obtained by transfection experiments,and the Exo was isolated.Compared with M0 group,the positive rate of CD86 of the macrophages in TAM group was decreased(P＜0.05),while the positive rate of CD206 was increased(P＜0.05),the expression levels of IL-1β and TNF-α proteins were decreased(P＜0.05),while the expression levels of IL-10 and TGF-β1 proteins were increased(P＜0.05).Compared with TAM group,the positive rate of CD86 of the macrophages in miR-761 Exo group was increased(P＜0.05),while the positive rate of CD206 was decreased(P＜0.05),the expression levels of IL-1β and TNF-α proteins were increased(P＜0.05),while the expression levels of IL-10 and TGF-β1 proteins were decreased(P＜0.05).Compared with control group,the fluorescence intensity of E-cadherin in the MG63 cells in TAM group was decreased,while the fluorescence intensity of Vimentin was increased,the expression level of E-cadherin protein was decreased(P＜0.05),while the expression levels of Vimentin,Twist1,Snail,and Slug proteins were increased(P＜0.05),and the numbers of invasion and migration cells were increased(P＜0.05).Compared with TAM group,the fluorescence intensity of E-cadherin in the MG63 cells in miR-761 Exo+TAM group was increased,while the fluorescence intensity of Vimentin was decreased,the expression level of E-cadherin protein was increased(P＜0.05),while the expression levels of Vimentin,Twist1,Snail,and Slug proteins were decreased(P＜0.05),and the numbers of invasion and migration cells were decreased(P＜0.05).Conclusion:The exo-delivered miR-761 can inhibit the EMT process of the OS cells,thereby inhibiting the cell migration and cell invasion;its mechanism may be related to regulating TAM polarization.

Objective:This study aimed to assess the effects of Peer Balint-style group on the empathy ability of third-year long-term medical students and to provide a theoretical and practical reference for effectively improving their humanistic quality.Methods:Ninety third-year Chinese long-term medicine students participated. Volunteers received either ten sessions of 1.5-h Peer Balint-style group which were led by specially trained peers from June 2019 to August 2019. The College Students' Empathy Ability Questionnaire was used before the experiment and the second day after the experiment. The total score of the scale from the pre-test and post-test and the scores of each dimension conformed to a normal distribution, with equal variance, describing in the form of ( x± s). Paired t-tests were performed to compare the total score and each dimension score before and after the intervention, using SPSS 22.0. Semi-structured interviews were conducted with 7 peer-group leaders and group members after the clinical practice period. The interview materials were analyzed by traditional content analysis. The content of the qualitative research was open-coded to obtain 10 categories, suggesting the role and inadequacy of Peer Balint-style groups. Results:A total of 63 valid samples were obtained. There was no significant difference of ( t=-0.44, P=0.661, P>0.05) between the total score of the post-test (118.00±11.98) and the total score of the pre-test (117.38±12.36). In each dimension, the reverse comprehension score of post-test (9.06±1.97) was significantly different ( t=-2.08, P=0.041, P>0.05) from the pre-test's (8.57±2.15), which increased compared to the pre-test score. Conclusions:Peer Balint-style group had a positive effect on improving empathy among medical students. Compared with the traditional Balint group, it has wider coverage, higher affinity and greater mobility. However, the design of the Peer Balint-style group still needs to be further improved.

Cardiovascular System/pathology* ; Constriction, Pathologic/genetics* ; Point Mutation ; Neurofibromin 1/genetics* ; Animals ; Mice

Humans ; Neoplasms, Second Primary/epidemiology* ; Neoplasms/epidemiology* ; Risk Factors ; Prognosis

Objective: To investigate the delay in identification, healthcare-seeking, and definitive diagnosis of tuberculosis among students in Urumqi City from 2010 to 2019, and to identify the influencing factors, so as to provide insights into tuberculosis control among students. Methods: The demographic and diagnosis data of tuberculosis patients in Urumqi City from 2010 to 2019 were captured from the Tuberculosis Information Management System of Chinese Disease Control and Prevention Information System. The delay in identification, healthcare-seeking and definitive diagnosis of tuberculosis was analyzed among students, and the factors affecting the delay in identification, healthcare-seeking and definitive diagnosis of tuberculosis were identified using a multivariable logistic regression model. Results: A total of 996 tuberculosis cases were identified among students in Urumqi City from 2010 to 2019. There were 702 students with delay in identification of tuberculosis (70.48%), 500 students with delay in healthcare-seeking (55.22%) and 534 students with delay in definitive diagnosis (53.61%). Multivariable logistic regression analysis identified active identification (OR=0.116, 95%CI: 0.032-0.420) as a factor affecting delay in identification of tuberculosis, women (OR=1.424, 95%CI: 1.104-1.836), non-local household registration (OR=1.311, 95%CI: 1.016-1.694) and active identification (OR=0.232, 95%CI: 0.064-0.848) as factors affecting delay in healthcare-seeking, and active identification (OR=0.143, 95%CI: 0.032-0.644) as a factor affecting delay in definitive diagnosis of tuberculosis among students. Conclusions There is a high proportion of delay in identification, healthcare-seeking and definitive diagnosis of tuberculosis among students in Urumqi City from 2010 to 2019, and female and non-locally household-registered students were at a high risk of delay in healthcare-seeking for tuberculosis. Active detection and screening of tuberculosis should be reinforced.

Objective:To evaluate the efficacy and safety of sodium hyaluronate gel in preventing adhesion after prophylactic enterostomy.Methods:One hundred and twenty four patients from 6 hospitals were enrolled in this prospective multi-center randomized controlled trial. Patients were randomized into the study group ( n=59) or the control group ( n=65).All patients underwent prophylactic enterostomy. Patients of study group received odium hyaluronate gel for adhesion-prevention,while those in control group did not receive any adhesion-prevention treatment. The incidence of moderate to severe adhesion around the incision in the stoma area were evalutated during stoma reduction surgery. Results:The incidence of moderate to severe adhesion around the incision in the stoma area was 6.3% in the study group, the difference was statistically significant ( P<0.05) compared to that of the control group (32.6%). Conclusion:Sodium hyaluronate gel can safely and effectively reduce the incidence of moderate and severe adhesions after abdominal surgery.

Objective:To analyze the genomic characteristics and variations of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) derived from an outbreak in inbound flight in Aug, 2022 in Beijing, and provide reference data for disease prevention and control and risk assessment.Methods:Fifty respiratory tract specimens from all cases in this outbreak were collected. The digital PCR (ddPCR) was used to determine the viral loads of the specimens. The full genome of the viruses were sequenced by Next-generation sequencing. Then analuses were performed on the genetic identity, variations and phylogenesis.Results:The median of viral loads in all 50 samples were 5.57×10 4 copies/ml and 5.85×10 4 copies/ml, for ORF1ab gene and N gene, respectively. A total of 46 SARS-CoV-2 genomes were obtained, which all belonged to Omicron/BA.5. Two genome clusters were observed, involving 21 and 7 cases, with a nucleotide sequence identities of 99.993% and 99.997%, respectively. Conclusions:The studied outbreak was composed of two main clusters and other individual cases with Omicron/BA.5 virus overseas.

Background Environmental pollutants can affect N⁶-methyladenosine (m⁶A) level in the body, but the change of m⁶A level in kidney after being exposed to cadmium (Cd) and the molecular mechanism of renal injury need to be further studied. Objective To analyze the associations of m⁶A modification and methyltransferases/demethylases with microRNA-21 (miR-21) and transforming growth factor- β1 (TGF - β1) in kidney of rats exposed to Cd. Methods Twenty-four SPF male SD rats were divided into 4 groups, with 6 rats in each group, and were exposed to Cd by subcutaneous injection of 2.0, 1.0, and 0.5 mg·kg⁻¹ cadmium chloride (CdCl₂) and equal volume of normal saline for 2 weeks, 7 d a week, respectively. The levels of N-acetyl-β-D-glucosidase (UNAG) and albumin (UALB) in urine, and the levels of m⁶A methylation and TGF-β1 in kidney were detected by enzyme-linked immunosorbent assay (ELISA). The level of blood urea nitrogen (BUN) was measured by urease method. The levels of renal oxidative stress indicators such as malondialdehyde (MDA), superoxide dismutase (SOD), and glutathione peroxidase (GSH-Px) were detected by total bile acid method, water-soluble tetrazolium asssay, and colorimetric method respectively. The relative levels of TGF-β1, methyltransferases, and demethylases in kidney were measured by reverse transcription-polymerase chain reaction. The expression of miR-21 in kidney was detected by fluorescent quantitative polymerase chain reaction. Results After 2 weeks of exposure to Cd, the body weights of rats in the 2.0 and 1.0 mg·kg⁻¹ cadmium chloride groups decreased, and the ratio of kidney/body weight and the levels of BUN, UNAG, and TGF-β1 mRNA and protein increased in the 2.0 mg·kg⁻¹ cadmium chloride group (P<0.05). The expression levels of m⁶A modification, methyltransferases METTL3, METTL14, Wilms’ tumor 1-associated protein (WTAP), and miR-21 were increased both in the 2.0 and 1.0 mg·kg⁻¹ cadmium chloride groups, with significant differences compared with the control group (P<0.05). The results of correlation analysis showed that the m⁶A modification level was negatively correlated with SOD (r=−0.4489, P<0.05) and GSH-Px (r=−0.4874, P<0.05), METTL3 was negatively correlated with MDA (r=−0.5158, P<0.05), while there was a positive correlation between FTO and GSH-Px (r=0.4802, P<0.05). In addition, miR-21 was positively correlated with METTL3 (r=0.7491), METTL14 (r=0.6157), and WTAP (r=0.6660) (P<0.05), TGF-β1 was positively correlated with METTL3 (r=0.5025, P<0.05) but negatively correlated with FTO (r=−0.5634, P<0.05) . Conclusion Cd can induce m⁶A methylation and up-regulation of METTL3, METTL14, WTAP, and miR-21 expression levels in rat kidney tissues, indicating that m⁶A and miR-21 may be associated with Cd-induced renal fibrosis.

OBJECTIVES: Quantitative magnetic resonance imaging has been successfully applied to assess the status of cartilage biochemical components. This study aimed to investigate the performance of 3.0T magnetic resonance imaging T mapping combined with texture analysis for evaluating the early degeneration of lumbar facet joints. METHODS: A total of 38 patients (20 in the asymptomatic group and 18 in the symptomatic group) were enrolled. All patients underwent 3.0T magnetic resonance imaging conventional sequences, water excitation three-dimensional spoiled gradient echo sequence (3D-WATSc), and T mapping scans. The bilateral L and L/S lumbar facet joints were morphological graded using the Weishaupt criteria, T values, and texture parameters derived from T mapping of cartilage. The Kruskal-Wallis test was used to compare the differences of parameters among different groups. Multivariate logistic regression analysis was used to obtain the independent predictive factors for evaluating the early degeneration of lumbar facet joints. Receiver operating characteristic (ROC) curve was performed and the area under curve (AUC) was calculated. Spearman correlation analysis was used to evaluate the correlation of the independent predictors of cartilage T value and texture parameters with the subjects' Japanese Orthopedic Association (JOA) score or Visual Analogue Scale (VAS) score. RESULTS: A total of 148 facet joints were selected, including 70 in Weishaupt 0 (normal) group, 58 in Weishaupt 1 group, and 20 in Weishaupt 2-3 group. T value, entropy, and contrast increased significantly as the exacerbation of facet joint degeneration (all <0.05), while the inverse difference moment, energy, and correlation decreased (all <0.05). Entropy among different groups was significantly different (all <0.05), and the differences of T value, contrast, inverse difference moment, and energy between Weishaupt 0 and Weishaupt 1 groups, or Weishaupt 0 and Weishaupt 2-3 groups were statistically significant (all <0.05). Multivariate logistic regression analysis suggested that T value and inverse difference moment were the independent predictors for evaluating early degeneration of facet joints. The combination of T value with inverse difference moment achieved the best performance in distinguishing Weishaupt 0 from Weishaupt 1 (AUC=0.85), with sensitivity and specificity at 92.7% and 76.5%, respectively. In the symptom group, the cartilage T value combined inverse difference moment was positively correlated with JOA score (=0.475, <0.05) and VAS score (=0.452, <0.05). CONCLUSIONS 3.0T magnetic resonance imaging T mapping combined with texture analysis is helpful to quantitatively evaluate the early degeneration of lumbar facet joints, in which the T value and inverse difference moment show an indicative significance．.
Algorithms ; Humans ; Lumbar Vertebrae ; Magnetic Resonance Imaging ; Sensitivity and Specificity ; Spondylosis ; Zygapophyseal Joint

Objective:To understand the epidemiological characteristics and clinical features of rotavirus-, norovirus-, adenovirus-and astrovirus-associ ated acute gastroenteritis in children under 5 years old in Beijing from Octorber, 2015 to March, 2017.Methods:In the intestinal clinic of 6 hospitals in 6 districts of Beijing, information and stool samples of the first 30 patients with acute gastroenteritis who are under the age of 5 years are collected monthly.Rotavirus, norovirus, adenovirus and astrovirus are identified by PCR.Descriptive epidemiological method was used to describe the epidemiological characteristics of diarrhea caused by rotavirus, norovirus, adenovirus and astrovirus in Beijing. One-way analysis of variance was used to analyze the Vesikari clinical severity score of of acute gastroenteritis caused by each virus. Unconditional logistic regression analysis was used to analysis the associated factors of clinical features.Results:Of the 2 052 samples, 709 (34.6%) were non-mixed infections: the positive rate of rotavirus, norovirus, adenovirus and astrovirus were 20.0%, 7.5%, 4.2% and 2.9%, respectively. A total of 135 cases (6.6%) were mixed infection. The mean and standard deviation of Vesikari clinical severity score was 8.0±3.1 for rotavirus associated acute gastroenteritis, which was significantly higher than norovirus (6.4±2.4, P<0.001), adenovirus (6.2±2.1, P<0.001) and astrovirus (6.1±2.0, P<0.001). The comparison of clinical features showed that compared with astrovirus, the children under 5 years old infected with rotavirus were more likely to have a diarrhea ≥5 days ( OR=3.334), have vomiting ≥3 times within one day ( OR=8.788), have vomiting≥1 day ( OR=3.963), have a Vesikari clinical severity score ≥11 severe cases ( OR=13.194). Norovirus infected cases were prone to have vomiting≥3 times in 1 day ( OR=5.710).Adenovirus infected cases were prone to have a diarrhea≥5 days ( OR=2.616). When using rotavirus as a reference, children under 5 years of age were less likely to develop fever≥38.4 ℃ after infection with norovirus ( OR=0.397) or adenovirus ( OR=0.280). Conclusions:The results of this study showed that the characteristics of acute gastroenteritis caused by different viruses are different. The clinical symptoms caused by rotavirus are more serious. Children under 24 months of age are at high risk of rotavirus infection. Effective preventive measures such as vaccination should be taken as soon as possible.