BACKGROUND: Increasing evidences support that the physical properties, especially stiffness, can regulate the directional differentiation of stem cells.OBJECTIVE: To review the effects of extracellular matrix on stem cell behaviors, and the research progress concerning the influence of physical properties of biomaterials on stem cell differentiation.METHODS: The first author retrieved CNKI and Web of Science databases using the keywords of extracellular matrix, bioscaffolds materials, chemical property, physical property, substrate rigidity, stem cell differentiation in Chinese and English, respectively. Finally, a total of 31 literatures were included for analysis.RESULTS AND CONCLUSION: The physicochemical properties expose effects on the cell proliferation, migration and differentiation, and especially the regulatory effect of stiffness on the cell differentiation has a revelation for tissue engineering and regenerative medicine. Searching for more biochemical and physical factors interacting with the stiffness of extracellular matrix will enable us to control cell behaviors accurately and to prepare an ideal scaffold closely similar to in vivo environment.

Objective To establish the modified Ziehl-Neelsen acid -fast staining method and to investigate the value of modi-fied Ziehl-Neelsen acid-fast staining method of bronchoalveolar lavage fluid in the diagnosis of pulmonary tuberculosis(TB)with negative sputum specimen.Methods 50 cases of negative sputum pulmonary TB were performed the bronchoalveolar lavage by the fiberoptic bronchoscope before the treatment,at the same time,the bronchoalveolar lavage fluids were collected and detected by the two methods of the traditional and modified Ziehl-Neelsen staining.The diagnostic positive rates were compared between the two groups.Results The positive rates of the two kinds of acid-fast staining method were 38% and 82% respectively,the difference showing statistical significance(P <0.05 ).Conclusion The modified Ziehl-Neelsen acid-fast staining of bronchoalveolar lavage fluid can highly improve the positive diagnostic rate of pulmonary TB patients with negative sputum and deserves to be clinically promoted.

Objective To investigate the association between vascular risk factors and the location of intracranial artery stenosis (anterior versus posterior).Methods Magnetic resonance angiography(MRA) were examined in 374 acute stroke patients.It was divided into two groups (anterior and posterior intracranial artery stenosis group).Analyzed possible risk factors.Results Univariate analysis showed there were differences between anterior and posterior intracranial artery stenosis in systolic blood pressure,history of smoking,drinking and stroke status,and national institutes of health stroke scale (NIHSS) score at discharge,short-term prognosis,serum creatinine,triglyceride,low density lipoprotein cholesterol (LDL-C) (P ＜ 0.05).In multivariate logistic regression analysis,high blood sugar (OR =1.135,95％ CI:1.003-1.284),history of stroke(OR =1.133,95％ CI:1.007-1.276),good short-term prognosis (OR =5.987,95％ CI:1.441-24.873) were preferentially related to anterior intracranial artery stenosis,whereas history of smoking (OR =0.003,95 ％ CI:0.000-0.376),high serum creatinine values (OR =0.509,95 ％ CI:0.328-0.790),high triglyceride values (OR =0.054,95％ CI:0.004-0.645) and high LDL-C values (OR =0.096,95％ CI:0.015-0.608) were preferentially related to posterior intracranial artery stenosis.Conclusion Vascular risk factors appeared to exert different effects of risk for anterior and posterior intracranial artery stenosis.

ObjectiveTo examine the clinical utility of four methods in diagnosis of tuberculous meningitis.Methods A total of 60 patients with tuberculous meningitis were included as study group and another 70 patients with non-tuberculous intracranial infection as control group. Four methods, including conventional acid fast stain,Myobacterium tuberculous culture in BACTEC MGIT 960, real-time lfuorescent quantitative polymerase chain reaction (FQ-PCR) and modiifed acid fast stain, were used to assay the cerebrospinal lfuid specimens for diagnosis of tuberculous meningitis.ResultsThe positive rate was 11.7% (7/60), 6.7% (4/60), 48.3% (29/60), and 61.7% (37/60), respectively in the study group as tested by the four methods. There was signiifcant difference between the four methods in the positive rate (P< 0.05). Modiifed acid fast stain was more sensitive than the other 3 methods in identifying tuberculous meningitis (P< 0.05). This method also could identify the intracellularM. tuberculosis. All the 8 samples from the 4 patients who were positive for culture ofM. tuberculosis were positive in the modiifed acid fast stain.Conclusions The modiifed acid fast staining method is simple, fast, signiifcantly more senstive in detection of the acid fastM. tuberculosis in CSF, either extracellular or intracellular. It is worthwhile to further investigate its usefulness in early diagnosis of tuberculosis meningitis.

[ ABSTRACT] AIM:To develop the cell model of polymer/liquid crystal and to study the effect of their elasticity on the adhesion of rat bone marrow mesenchymal stem cells (rBM-MSCs).METHODS: Using the method of solvent e-vaporation induced phase separation, the cell model of polymer/liquid crystal was constructed.The surface morphology and phase separation structure were determined by polarized optical microscopy ( POM) , scanning electron microscopy ( SEM) and small angle X-ray scattering ( SAXS ) .rBM-MSCs were separated and expanded by adherent culture.The surface markers of rBM-MSCs were detected by flow cytometry.The cells were induced to osteogenic differentiation and adipogenic differentiation for 2 weeks.After 3 passages, the cells were divided into 4 groups, including total PU control group, 10%membrane group, 30%membrane group and 50%membrane group.The cells were then incubated with rhodamine phalloi-din for cytoskeleton staining and were observed under the confocal laser scanning microscope after cultured for 24 h.RE-SULTS:The cell model of polymer/liquid crystal was constructed successfully using the method of solvent evaporation in-duced phase separation.Flow cytometry results showed that the rBM-MSCs positively expressed CD29, CD44 and CD90, and negatively expressed CD34 and CD45.After stained with alizarin red S and oil red O, the calcium nodule and lipid droplets in rBM-MSCs were observed obviously.The cytoskeleton staining result indicated that the area in total PU control group, 10%membrane group and 30%membrane group were greater, and the actin microfilaments were also clearer than
that in 50%membrane group.CONCLUSION:The cell model with suitable content of liquid crystal made a contribution to the rBM-MSCs’ adhesion, but too much liquid crystal inhibits cell adhesion.

BACKGROUND: Though there were many experiments addressing repairing osteochondral defects before, faulty restoration occurred at coupling interfaces. OBJECTIVE: To investigate the feasibility of repairing of osteochondral composite defects in rabbit knees with animal-origin osteochondral scaffold combined with bone marrow mesenchymal stem cells (BMSCs)/chondrocytes.METHODS: New Zealand white rabbits were randomly divided into the experimental, control and blank groups and prepared for unilateral knee joint osteochondral defects. Animal-origin osteochondral scaffold combined with BMSCs/chondrocytes, animal-origin osteochondral scaffold and no material was implanted to repair the defects in the experimental, control and blank groups, respectively. Healing condition was evaluated by gross observation, hematoxylin-eosin staining, and toluidine blue staining at 4, 8, and 12 weeks after operation. RESULTS AND CONCLUSION: At 12 weeks after operation, gross observation showed the defects were repaired completely without local depression and the regenerated tissues were fused with surrounding tissues in the experimental group. Hematoxylin-eosin staining and toluidine blue staining revealed that there were many new hyaline cartilages in the cartilage defects in which columnar cells were lined well and cartilage lacuna was obviously, also, there were many bony tissues in the bone defects. The regeneration cartilage, the underlying subchondral bone and host bone were coupled completely. The toluidine blue positive rate and histologic scores of the experimental group were superior to those of the control and blank groups (P < 0.05). It is demonstrated that animal-origin osteochondral scaffold combined with BMSCs/chondrocytes is an ideal method to repair defects between cartilage and the underlying subchondral bone.

The patient, a 50-year-old male, was admitted to the hospital on April 1, 2020 with the chief complaint of "confusion with vomiting for 1 hour due to falling from height ", and the emergency craniotomy was performed. Intermittent fever with a maximum temperature of 38 ℃ occurred 3 days after the surgery, and the inflammation indexes were all higher than the upper limit of the reference values. Recurrent fever remained despite after empirical anti-infection treatment. On April 12, the patient was treated with vancomycin combined with meropenem after cerebrospinal fluid specimens routine and biochemical tests suggested intracranial infection. After 48 hours of cultivating the cerebrospinal fluid and blood specimens, some small, clear, needle-like colonies were found and they were identified as Mycoplasma humanum by using 16S rRNA gene. Eventually, the patient died due to the severity of the disease and complications.

Objective To investigate the changes and clinical significance of plasminogen activator inhibi-tor-1(PAI-1),transforming growth factor-β(TGF-β),vascular endothelial growth factor(VEGF),and inter-leukin-6(IL-6)in patients with tuberculous pleurisy and pleural fibrosis.Methods A total of 103 patients with tuberculous pleurisy and pleural fibrosis who were treated in a hospital from July 2020 to July 2023 were selected as the research subjects.After 2 weeks of treatment,they were divided into a significant effect group and a non-significant effect group based on the therapeutic efficacy of glucocorticoid treatment.The levels of PAI-1,TGF-β,VEGF,and IL-6 in serum and pleural effusion were compared before treatment,after 1 and 2 weeks of treatment.The correlation between the levels of PAI-1,TGF-β,VEGF,and IL-6 in serum and pleural effusion and the therapeutic efficacy was analyzed by Spearman correlation analysis.Pearson correlation analy-sis was used to analyze the correlation between the levels of PAI-1,TGF-β,VEGF,and IL-6 in serum and pleu-ral effusion and the levels of these indicators in pleural effusion after 2 weeks of treatment.A receiver operat-ing characteristic curve was drawn to analyze the predictive value of the levels of PAI-1,TGF-β,VEGF,and IL-6 in serum and pleural effusion for the efficacy of tuberculous pleurisy and pleural fibrosis patients after 1 and 2 weeks of treatment.Results The levels of PAI-1,TGF-β,VEGF,and IL-6 in serum and pleural effusion after 1 and 2 weeks of treatment in both groups were lower than those before treatment,and the levels of PAI-1,TGF-β,VEGF,and IL-6 in serum and pleural effusion after 1 and 2 weeks of treatment in the significant effect group were lower than those in the non-significant effect group,with statistically significant differences(P＜0.05).The levels of PAI-1,TGF-β,VEGF,and IL-6 in serum and pleural effusion after 1 and 2 weeks of treatment were negatively correlated with the efficacy(P＜0.05).The levels of PAI-1,TGF-β,VEGF,and IL-6 in serum and pleural effusion after 2 weeks of treatment were positively correlated(r=0.761,0.783,0.812,0.741,all P＜0.05).The area under the curve(AUC)of combined detection of serum and pleural effusion in-dicators after 1 and 2 weeks of treatment was greater than the AUC of individual indicators(P＜0.05).Con-clusion The levels of PAI-1,TGF-β,VEGF,and IL-6 in serum and pleural effusion of patients with tubercu-lous pleurisy and pleural fibrosis are related to the efficacy of treatment.The combined detection of PAI-1,TGF-β,VEGF,and IL-6 in serum and pleural effusion has good predictive value and can provide reference for clinical intervention.

ObjectiveTo observe the efficacy and safety of Tongguan Capsule（通冠胶囊）on ventricular remodeling in patients after acute myocardial infarction （AMI）， and to explore the possible mechanism. MethodsA total of 53 ST-segment elevation myocardial infarction （STEMI） patients were collected and randomly divided into 26 cases in the treatment group and 27 cases in the control group. The control group was given conventional therapy after percutaneous coronary intervention （PCI） for AMI， and the treatment group was given Tongguan Capsules （4.5 g each time， 3 times a day） on the basis of the control group. The course of treatment was 12 weeks. Echocardiographic data and stool samples were collected from subjects before and after the intervention， and left ventricular ejection fraction （LVEF）， left ventricular end-diastolic volume index （LVEDVi）， left ventricular end-systolic volume index （LVESVi）， left ventricular mass index （LVMi） were measured and calculated， so as to compare the number of cases of left ventricular remodeling in the two groups. At the same time， 16S rDNA sequencing was performed on the stool samples to analyze the diversity of gut microbiota （GM）， the composition of the GM， the GM difference between the groups； recording the incidence of major adverse cardiovascular events （MACEs） and adverse reactions of patients in the two groups during the study period； and performing Spearman's correlation analyses of the post-treatment flora data with LVEF， LVEDVi， LVESVi， LVM， and LVMi in the two groups. ResultsOne case fail to follow up in the treatment group and 2 cases fail to follow up in the control group， and 25 cases in each of the two groups were finally included in the analysis. LVEDVi， LVESVi， and LVMi of the control group after treatment were higher than those before treatment （P＜0.05）； after treatment， LVEDVi， LVESVi and LVMi in the treatment group were lower than those in the control group （P＜0.05）. Left ventricular remodeling occurred in 5 cases （20.00%） in the treatment group and 13 cases （52.00%） in the control group， and the incidence of left ventricular remodeling in the treatment group was lower than that in the control group （P=0.03）. After treatment， the ACE estimation and Chao estimation of bacterial abundance in the treatment group were higher than that before treatment and that in the control group （P＜0.05）. The treatment group showed an increase in Mycobacterium anisopliae phylum and a decrease in Mycobacterium thickum， Mycobacterium anisopliae phylum， and Mycobacterium patella phylum after treatment （P＜0.05）. When comparing between groups after treatment， the relative abundance of Prevotella， Agathobacter， Dialister， Eubacterium coprostanoligenes group was up-reuglated and the relative abundance of Enterococcus was down-regulated in the treatment group（P＜0.05 or P＜0.01）. There was no statistically significant difference in the incidence of MACEs and the occurrence of adverse reactions between groups during treatment （P＞0.05）. The results of correlation analysis showed that Prevotella were positively correlated with LVEF and negatively correlated with LVEDVi， LVESVi， LVM， and LVMi （P＜0.01）. Agathobacter group were negatively correlated with LVEDVi， LVESVi （P＜0.01）； Enterococcus group were positively correlated with LVESVi （P＜0.05）. ConclusionTongguan Capsules can improve ventricular remodeling in patients with acute ST-segment elevation myocardial infarction with better safety； its mechanism may be related to adjusting the enrichment of related bacteria such as Prevotella， Dialister and Enterococcus and other related bacterial genera， increasing the colonization and diversity of beneficial bacteria， and adjusting the structure of GM.