Objective: To evaluate the performance of 5T magnetic resonance imaging (MRI) in visualizing dental pulp and periodontal ligament (PDL) tissues in vivo in the young adult population, thereby providing a basis for the application of high-field MRI technology in clinical oral examinations. Methods: The study was approved by the Ethics Committee of the hospital. A total of 15 healthy volunteers (413 permanent teeth altogether) were recruited and underwent full-mouth 5T MRI scans. Among them, six volunteers (168 permanent teeth) also received both 3T MRI and cone-beam computed tomography (CBCT) scans. Two dental specialists independently evaluated the imaging quality of the dental pulp and PDL on the images using a 5-point Likert scale and recorded the number of detectable root canals for each tooth. Inter-rater agreement was assessed using weighted kappa statistics and intraclass correlation coefficient (ICC). Non-parametric tests were employed to compare differences in imaging performance among different tissue structures, tooth positions, and imaging modalities. Results: 5T MRI can achieve in vivo imaging for most dental pulp tissues and partial periodontal membrane structures. There was a high level of agreement between the two raters in their imaging scores for the dental pulp and PDL (dental pulp κ = 0.934, PDL κ = 0.737). The imaging scores for dental pulp were significantly higher than those for PDL (P < 0.001), and the scores for molar dental pulp were lower than those for premolars and anterior teeth. In the multimodal comparison involving six volunteers, the raters showed good consistency in scoring dental pulp and PDL imaging across 5T MRI, 3T MRI, and CBCT, as well as in root canal counts (5T MRI for dental pulp κ = 0.971, 3T MRI for dental pulp κ = 0.933, CBCT for dental pulp κ = 0.964; 5T MRI for PDL κ = 0.625, 3T MRI for PDL κ = 0.667, CBCT for PDL κ = 0.571; ICC for root canal counts all ≥ 0.990). The imaging scores for dental pulp and PDL using 5T MRI were significantly higher than those using 3T MRI (dental pulp: P < 0.001; PDL: P = 0.022), but there was no statistically significant difference in the detection rate of the number of root canals between the two (P > 0.05). Although the imaging scores for dental pulp and PDL as well as the detection rate of the number of root canals with 5T MRI were inferior to those with CBCT (dental pulp: P < 0.001; PDL: P = 0.02; number of root canals: P < 0.05), 5T MRI can truly achieve "direct imaging" of these two soft tissues. Conclusion 5T MRI enables effective in vivo direct imaging of dental pulp and PDL tissues in the young adult population, indicating its potential clinical application value in the diagnosis and treatment of pulp and periodontal diseases.

BACKGROUND:The capability of repairing articular cartilage damage is very limited,and tissue engineering technology provides new therapeutic options for repairing damaged cartilage,in which the interaction and induction between chondrocytes,bone marrow mesenchymal stem cells,and synovial mesenchymal stem cells is the basis of autologous healing of cartilage damage. OBJECTIVE:To construct the chondrocyte-bone marrow mesenchymal stem cell-synovial mesenchymal stem cell co-culture system to simulate the in vitro microenvironment of chondrocytes,and to explore the optimal cell inoculation ratio,meanwhile to observe the effects of icariin-containing serum on the proliferation of chondrocytes and the chondrogenic differentiation of stem cells in the system. METHODS:Rat knee chondrocytes,bone marrow mesenchymal stem cells and synovial mesenchymal stem cells were extracted,cultured and identified,and a chondrocyte-bone marrow mesenchymal stem cell-synovial mesenchymal stem cell non-contact co-culture system was constructed according to different cell inoculation ratios.After 72 hours of co-culturing,the chondrocyte proliferative activity and phenotypic ability were observed,and the co-culture system with the best overall effect was selected.New Zealand white rabbits were gavaged with icariin solution(0.25 mg/mL)to prepare icariin-containing serum,and cultured in conventional complete medium(high sugar DMEM culture medium containing 10%fetal bovine serum and 1%double antibody by volume)as the control group,while the experimental group was intervened by adding 10%icariin-containing serum by volume on the basis of above.The proliferative activity of chondrocytes and the expression of collagen type II were tested for the two groups after 24 and 48 hours.The differentiation of bone marrow mesenchymal stem cells and synovial mesenchymal stem cells into chondrocytes in the co-culture system was tested by immunofluorescence staining after 14 days. RESULTS AND CONCLUSION:(1)The three kinds of cells grew normally adherently to the wall in different ratios of co-culture,where chondrocytes showed the best proliferative activity and phenotypic ability in the co-culture system when chondrocytes:bone marrow mesenchymal stem cells:synovial mesenchymal stem cells=2:1:1.(2)Compared with the control group,the proliferative activity and type II collagen expression of chondrocytes in the experimental group were significantly increased after 24 hours(P<0.01),and the two groups still had difference after 48 hours(P<0.05).The two groups showed obvious chondrogenic differentiation of bone marrow mesenchymal stem cells and synovial mesenchymal stem cells after 14 days(P<0.01),and some of the cells appeared round or oval,and the cytoplasmic type II collagen immunofluorescence staining was positive.The fluorescence intensity of the experimental group was significantly higher than that of the control group(P<0.01).(3)The results showed that the chondrocyte-bone marrow mesenchymal stem cell-synovial mesenchymal stem cell co-culture system could be successfully established by the non-contact co-culture method,and the best chondrocyte proliferative activity and phenotypic ability could be obtained when the cell ratio was 2:1:1.Icariin-containing serum had the promoting effect on chondrocyte proliferation,and chondrogenic differentiation of bone marrow mesenchymal stem cells and synovial mesenchymal stem cells in the system.

Access to the clinical application of medical technology is one of the core institutional contents of medical quality management， involving medical quality assurance， the achievement of patient safety goals， and medical service satisfaction. Medical technology is only permitted for clinical use after its safety and effectiveness have been verified through clinical research， as well as evaluated and reviewed by the medical technology clinical application management committee and ethics committee of this medical and health institution. Based on the relevant laws， regulations， and ethical principles， combined with the experience of ethical review in the clinical application of medical technology from some medical and health institutions， a thematic discussion was held to formulate ethical review guidelines for the clinical application of medical technology for references. These guidelines elaborated on the management system for access to the clinical application of medical technology in medical and health institutions， the system of ethics committees and the requirements of review norms， technical plans and their review points， key points for the implementation of informed consent， technical teams and conditions， and other aspects.

Five saponins were isolated from the kernels of Momordica cochinchinensis, by macroporous resin, silica gel, ODS column chromatography, and semi preparative HPLC. Based on MS and NMR analysis, combining with alkaline hydrolysis and acid hydrolysis, their structures were identified as: gypsogenin-3-O-{β-D-galactopyranosyl (1→2)-[α-L-rhamnopyranosyl (1→3)]-β-D-glucuropyranonosyl}-28-O-β-D-xylopyranosyl (1→3)-[β-D-xylopyranosyl (1→4)]-α-L-rhamnopyranosyl (1→2)-β-D-fucopyranoside (1), quillaic acid-3-O-{β-D-galactopyranosyl (1→2)-[α-L-rhamnopyranosyl (1→3)]-β-D-glucuropyranonosyl}-28-O-β-D-xylopyranosyl (1→3)-[β-D-xylopyranosyl (1→4)]-α-L-rhamnopyranosyl (1→2)-β-D-fucopyranoside (2), gypsogenin-3-O-β-D-galactopyranosyl (1→2)-[α-L-rhamnopyranosyl (1→3)]-β-D-glucuropyranonoside sodium (3), quillaic acid-3-O-β-D-galactopyranosyl (1→2)-[α-L-rhamnopyranosyl (1→3)]-β-D-glucuropyranonoside sodium (4), 18α-quillaic acid-3-O-β-D-galactopyranosyl (1→2)-[α-L-rhamnopyranosyl (1→3)]-β-D-glucuropyranonoside (5). Compounds 1-5 were new compounds, and named as mubezhisides A, B, C, D, E, respectively. They all could obviously inhibited the growth of Candida albicans, C. parapsilosis, and C. tropicalis.

ObjectiveTo understand the infection characteristics of multidrug-resistant organisms (MDROs) in hospitalized patients in a tertiary sentinel hospital in Shanghai, so as to provide an evidence for the development of targeted prevention and control measures. MethodsData of MDROs strains and corresponding medical records of some hospitalized patients in a hospital in Shanghai from 2021 to 2023 were collected, together with an analysis of the basic information, clinical treatment, underlying diseases and sources of sample collection. ResultsA total of 134 strains of MDROs isolated from hospitalized patients in this hospital were collected from 2021 to 2023 , including 63 strains of methicillin-resistant Staphylococcus aureus (MRSA), 57 strains of carbapenem-resistant Acinetobacter baumannii (CRAB), and 14 strains of carbapenem-resistant Klebsiella pneumoniae (CRKP). Of the 134 strains, 30 strains were found in 2021, 47 strains in 2022 and 57 strains in 2023. The male-to-female ratio of patients was 2.05∶1, with the highest percentage (70.90%) in the age group of 60‒<90 years. The primary diagnosis was mainly respiratory disease, with lung and respiratory tract as the cheif infection sites. There was no statistically significant difference in the distribution of strains between different genders and infection sites (P>0.05). However, the differences in the distribution of strains between different ages and primary diagnosis were statistically significant (P<0.05). Patients who were admitted to the intensive care unit (ICU), had urinary tract intubation, were not artery or vein intubated, were not on a ventilator, were not using immunosuppresants or hormones, and were not applying radiotherapy or chemotherapy were in the majority. There was no statistically significant difference in the distribution of strains for whether received radiotherapy or chemotherapy or not (P>0.05), while the differences in the distribution of strains with ICU admission history, urinary tract intubation, artery or vein intubation, ventilator use, and immunosuppresants or hormones use or not were statistically significant (all P<0.05). The type of specimen was mainly sputum, the hospitalized ward was mainly comprehensive ICU, the sampling time was mainly in the first quarter throughout the year, the number of underlying diseases was mainly between 1 to 2 kinds, the application of antibiotics ≥4 kinds, and those who didn’t receive any surgery recently accounted for the most. There were statistically significant differences in the distribution of strains between different specimen types, wards occupied and history of ICU stay (P<0.05), but no statistically significant difference in the distribution of strains between different sampling times, number of underlying diseases and types of antibiotics applied (P>0.05). ConclusionThe situation of prevention and control on MDROs in this hospital is still serious. Focus should be placed on high-risk factors’ and infection monitoring and preventive measures should be strengthened to reduce the incidence rate of MDROs infection.

Objective: To explore the key factors affecting the selection and effectiveness of bladder management modalities in patients with spinal cord injury，so as to provide reference for the optimization of individualized bladder management strategies. Methods: The clinical and follow-up data of 78 patients with spinal cord injury treated in our hospital during Jan.1,2013 and Dec.31,2022 were retrospectively analyzed.The distribution of bladder management modalities among different grades of injuries was analyzed. Bowker symmetry test was used to evaluate the difference between bladder management modalities at discharge and at the end of follow-up. Multiple linear regression was used to explore the influencing factors of bladder management effects. Plotting Kaplan-Meier survival curves were adopted to calculate the median time of changes in bladder management. Results: At discharge，there were 9 cases of self-catheterization，19 cases of intermittent catheterization，22 cases of reflexive voiding，26 cases of long-term catheterization，and 2 cases using urinary collector.At the end of follow-up，there were 15 cases of self-catheterization，8 cases of intermittent catheterization，34 cases of reflexive voiding，14 cases of long-term catheterization，and 7 cases using urinary collector.There was a significant difference between the modalities of bladder management at discharge and at the end of follow-up (χ =21.43，P=0.018).Multiple linear regression showed a significant decrease of 8.60 in the total neurogenic bladder symptom score (NBSS) for grade D injuries compared with grade A injuries (P=0.026). The median time to bladder management change was 7.93 months (95%CI:5.44-9.44), with approximately 50% of patients experiencing a change in bladder management within 8 months after discharge. Conclusion: The modalities of bladder management changed significantly after discharge.The grade of injury was a key factor affecting the effectiveness of bladder management.Higher grade was associated with worse effectiveness of bladder management.