BACKGROUND:Tissue and cellimplantation entails high-quality seed cells. In order to satisfy this requirement, it is crucial to produce adequate wel-conditioned, high-purity and strong proliferation ability bone marrow-derived mesenchymal stem cells.
OBJECTIVE:To establish a simple, rapid and effective in vitro isolation and culture method of bone marrow-derived mesenchymal stem cells, and to define the biological features of bone marrow mesenchymal stem cells.
METHODS:Rat bone marrow mesenchymal stem cells were isolated from the bilateral tibial and femoral bones by the method of whole bone marrow, then purified and passaged by attachment method. The morphology and features of bone marrow mesenchymal stem cells were observed, the growth curve was drawn and the cellsurface antigen was detected by flow cytometry. The bone marrow mesenchymal stem cells were induced to differentiate along the osteogenic, chondrogenic and adipogenic lineages.
RESULTS AND CONCLUSION:Bone marrow mesenchymal stem cells isolated by the whole bone marrow adherence method grew vigorously and were highly purified. The cultured cells were spindle-shaped. The growth curve was S-shaped and the population doubling time was 29 hours. The cells stil maintained a strong proliferative capacity after they were passaged for 10 generations. The surface markers such as CD44, CD29, CD90 were positive, while CD45, CD34, CD11b were negative. At the third passage, bone marrow mesenchymal stem cells were induced to differentiate along the osteogenic, chondrogenic and adipogenic lineages, respectively. Fol owing induction, Alizarin red staining, alkaline phosphatase staining, von-kossa mineralized nodules staining, toluidine blue staining, and oil red O staining were al positive. This shows that the whole bone marrow adherence method is a simple and reliable method for the in vitro isolation, culture and proliferation of bone marrow mesenchymal stem cells. Moreover, they have multi-lineage differentiation capacity under different inducers. The third passage bone marrow mesenchymal stem cells have the highest biological activity and can act as the ideal seed cells for subsequent experiments.

Nowadays more and more medical study fields need mathematics knowledge.The mathematics abilities of medical students include the ability of basic logic thought,changing medical problems into mathematics ones,understanding and applying mathematics knowledge as well as solving mathematics problems with computers.

ObjectiveTo study the treatment and prognosis of the breast phyllodes tumors.MethodsKG1Clinical data, and the results of follow-up in 203 cases of breast phyllodes tumors were analyzed using Logistic analysis and Cox regression in SPSS statistic software.ResultWT5”BZLocal recurrence and tumor mortality were in direct proportion to the pathologic grade of the tumor. There was a direct proportion between local recurrence and tumor infiltration; and between tumor caused-mortality and tumor mitosis and necrosis.Mitotic activity and tumor necrosis were the independent prognostic factors. After surgical resection 21 1% of patients with benign tumor, 45 2% of patients with borderline tumor, 64 3% of patients with malignant tumor suffered recurrence. The 5-year survival rate was 100% in patients with benign phyllodes tumor, 92 0% with borderline tumor, and 33 3% with malignance.KG2Conclusion Local excision is not the appropriate treatment for phyllodes tumor. Patients with benign or borderline phyllodes tumor should undergo wide local excision including a margin of uninvolved tissue, and that with local recurrent borderline and malignant phyllodes tumor receive mastectomy.

Objective To evaluate the effectiveness and safety of open tension-free hernioplasty and two kind of laparoscopic hernia repair for the treatment of primary unilateral inguinal hernia. Methods Patients suffering from primary unilateral inguinal hernia were randomly divided into 3 groups to undergoopen operation with mesh-plug and patch or transabdominal preperitoneal hernioplasty (TAPP) or totally extraperitoneal hernioplasty (ZEP). Results From February 2006 to February 2009, a total of 164patients were divided into 3 groups, with 62 undergoing open tension-free mesh-plug hernia repair, 50receiving TAPP and 52 receiving TEP. Postoperative patients were then followed up for a period of(16±8)months. The average operating time for the patients in the open mesh repair group was significantly shorter compared to the other two groups (P＜0.01 ). The cost in the open mesh repair group was also significantly lower than the other two groups (P＜0.01). The pain scores in open mesh group were significantly higher than those in the other two groups (P＜0.01). The hospital stay and the recovery time were both significantly longer in the open mesh repair group (P＜0.01) compared to the other two groups. No major complications and recurrence was found in neither groups. Conclusions Open tension-free mesh-plug hernia repair, TAPP and TEP are all safe and effective for the treatment for patients with primary unilateral inguinal hernia. TAPP and TEP are superior to open tension-free mesh-plug hernia repair as these two procedures involve less postoperative pain and fast recovery.

Objective To investigate CT features of primary ileocecum lymphoma (PIL),to improve the ability of CT diagnosis for the disease.Methods CT data of 12 patients with PIL confirmed by surgery and pathology were analyzed retrospectively.All of the patients underwent plain CT, and 8 cases of them also underwent enhanced CT.Results Among the 12 cases of PIL, there were mass type in 2 and diffused thickness type in 10.The length of the intestinal lesions ranged from 7.8 to 18.5 cm (mean 10.2 cm).Lumen was irregular or aneurysmal dilation in 9, and obvious stenosis in 3.Intestinal wall was soft in 10,and rigid in 2.Plain CT showed that the thickened intestinal wall was soft tissue density.Among the 8 cases performed enhanced CT,6 were approximately homogeneous enhancement, and 2 had small necrosis area without enhancement.Maximum intensity projection(MIP) displayed the lesion had blood supply from the branches of the superior mesenteric artery.Enlarged lymph nodes were detected around the lesions, in root of the mesentery, and in the retroperitoneum in 9.1 case was accompanied with intestinal obstruction,1 case was accompanied with intestinal perforation.Conclusion If CT examination found a homogeneous soft tissue mass in ileocecum with long extent, lumen dilation, soft intestinal wall,mild-to-moderate delayed homogeneous enhancement, PIL should be considered.

Objective:To explore the risk factors of bacterial infections in patients with decompensated hepatitis B cirrhosis and to construct a risk prediction model.Methods:The clinical data of 198 patients with decompensated hepatitis B cirrhosis admitted in Zhejiang Provincial People’s Hospital from January 2014 to April 2020 were retrospectively analyzed. There were 86 patients with bacterial infection (infection group) and 112 patients without bacterial infections (non-infection group). The risk factors of bacterial infections were analyzed by multivariate Logistic regression. R language was used to establish a nomogram model to predict the risk of bacterial infection in patients with decompensated hepatitis B cirrhosis. Receiver operating characteristic (ROC) curve was used to explore the prediction efficiency of the nomogram model for bacterial infection.Results:Multivariate logistic regression analysis showed that previous smoking history, prothrombin time, neutrophil count and hypersensitive C protein were independent risk factors for bacterial infection in patients with decompensated hepatitis B cirrhosis ( P<0.05 or <0.01), while regular antiviral treatment and high-density lipoprotein were protective factors ( P<0.05 or <0.01). ROC curve showed that the area under the curve (AUC) of risk prediction model for bacterial infections was 0.872 (95% CI 0.820-0.924, P<0.01), and AUC of MELD score for predicting bacterial infections was 0.670 (95% CI 0.599-0.735, P<0.01); the risk prediction model was superior to MELD score in prediction ( Z=4.89, P<0.01). Conclusions:The established risk prediction model in this study can more accurately predict the occurrence of bacterial infections in patients with decompensated hepatitis B cirrhosis.

Objective:To investigate the effects of mindfulness based stress reduction on irritable bowel syndrome.Methods:PubMed,EMBASE,Cochrane Library,Web of Science,CNKI,Wanfang Data was searched and randomized clinical trials of MBSR treatment in irritable bowel disease were involved.At last two reviewers extracted the data independently.According to Cochrane Handbook5.1.0 handbook,a quality assessment was made.All the data would be analyzed with meta-analysis by the software of Stata.Results:Totally 5 randomized controlled trials were eligible,including 461 participants.Meta-analysis showed that MBSR would be better therapy method to improve the symptom severity of irritable bowel syndrome in 3 months,[SMD =-0.60,95％ CI:-0.86 ～-0.34,P ＜0.01],and the pain index at the 3 months and 6 months was relieved compared to the baseline [SMD =-1.11,95％ CI:-1.45 ～-0.76,P ＜ 0.01,SMD =-0.14,95％ CI:-0.43 ～ 0.14,P ＜ 0.05].Conclusion:Mindfulness based stress reduction therapy could be a adjunctive therapy method in treatment of irritable bowel syndrome.

Objective To observe among stroke survivors the timing of muscle activation at the stance phase during walking using the surface electromyography ( sEMG) combined with 3D gait analysis. Methods Twenty stroke survivors assessed as at Brunnstrom stages Ⅲ, Ⅳ and Ⅴ were assigned to groups designated Ⅲ, Ⅳ and V. sEMG and 3D gait analysis were used to assess the activation timing of the bilateral rectus femoris ( RF) and biceps femoris ( BF) , the tibialis anterior ( TA) and the gastrocnemius medialis ( GM) . The activation timing and the dura-tion of activation of the muscles were compared among the 3 groups, as well as with those of healthy muscles. Results The onset time of the RF on the affected side was significantly later than on the healthy side, while that of the GM was significant earlier. The durations of BF and GM activation on the affected side were significantly shorter than on the unaffected side in group III. The onset times of the TA and GM on the affected side were significantly ear-lier than on the healthy side in group IV, as was the onset time of the TA of the affected side in group V. The average RF and BF onset times on the affected side in group Ⅳ were significantly earlier than in group Ⅲ. The onset time of the TA on the unaffected side and the average BF onset time on the affected side in group Ⅴ were significantly later than in group IV. The onset time of the RF and TA on the unaffected side in group Ⅳ and the onset time of the GM on the affected side were significantly later than in group III, while the onset time of the BF and TA on the affected side was significantly earlier. The average duration of BF activation on the unaffected side in group Ⅳ was significant-ly shorter than that of group Ⅲ. The average duration of TA activation on the unaffected side in group Ⅴ was signifi-cantly shorter than that of group IV. The duration of RF activation on the affected side in group Ⅴ was significantly shorter than that in group Ⅲ, and the same was true of the RF, BF, TA and GM activation times on the healthy side. Conclusions There are significant differences in the onset and duration of muscle activation when stroke survivors at different stages of recovery walk. Some muscles are activated too early and others are over-activated. These abnormali-ties gradually disappear with the recovery of motor function.

Objective:Digestive endoscopy is an important diagnostic and therapeutic tool for digestive system diseases.The artificial intelligence(AI)-assisted system in endoscopy(hereinafter referred to as AI in digestive endoscopy)has broad application prospects in the field of digestive endoscopy.The trust and acceptance of endoscopic subjects are the cornerstone of the research,application,and promotion of AI in digestive endoscopy.Currently,the tools for measuring the acceptance of AI in digestive endoscopy by subjects are limited at home and abroad.This study aims to develop a scale for measuring the acceptance of AI in digestive endoscopy by subjects,then to evaluate its reliability and validity. Methods:By conducting literature research,an item pool and dimensions were constructed,and a preliminary scale was constructed using Delphi method.Through the first stage of the survey on the subjects,the reliability and validity of the scale were tested,and the revised scale was used for the second stage of survey on the subjects to further verify the structural validity of the scale. Results:The acceptance scale for AI in digestive endoscopy included 11 items in 3 dimensions:accuracy,ethics,benefit and willingness.In the first stage of the survey,351 valid questionnaires were collected,and the Cronbach's α was 0.864.The correlation coefficient between the total score of the scale and the score of the test item was 0.636,and the Kaiser-Meyer-Olkin(KMO)value in exploratory factor analysis was 0.788.In the second stage of the survey,335 valid questionnaires were collected,and in confirmatory factor analysis,the χ2/df was 3.774,while the root mean squared error of approximation(RMSEA)was 0.091. Conclusion:Acceptance scale for AI in digestive endoscopy by subjects developed in this study has good reliability and validity.

Objective:To investigate the predictive value of cerebroplacental ratio (CPR) for adverse perinatal outcomes of induction of labor in prolonged pregnancy.Methods:This retrospective study recruited 315 singleton pregnant women who had induced labor due to prolonged pregnancy (≥41 gestational weeks) in the First Affiliated Hospital of Chongqing Medical University from January 1, 2019 to April 30, 2020. Based on the occurrence of adverse perinatal outcomes (emergency delivery due to persistent abnormal fetal heart rate monitoring, umbilical artery blood pH at birth <7.2, 5 min Apgar scores<7, transferring to neonatal intensive care unit after birth, chorioamnionitis and vaginal delivery converted to cesarean section), they were divided into two groups: case group ( n=76) and normal group ( n=239). Clinical features and umbilical artery blood flow, middle cerebral artery (MCA) flow and CPR measured in the last ultrasound scan before induction were compared between the two groups using student's t-test, Mann-Whitney U test and Chi-square test. Receiver operating characteristic (ROC) curve was used to analyze the predictive values of umbilical artery blood flow, MCA flow and CPR for the adverse perinatal outcomes. Multivariate logistic regression analysis was used to screen the meaningful predictors. Results:Compared with the normal group, the umbilical artery pulsatility index (PI) (0.9±0.1 vs 0.8±0.1, t=-5.458, P<0.001) and the percentage of abnormal CPR (<1.0) increased significantly [21.1%(16/76) vs 6.3%(15/239), χ2=14.190, P<0.001] in the case group, while the MCA-PI and CPR decreased significantly (1.1±0.2 vs 1.3±0.3, t=5.658, P<0.001; 1.2±0.3 vs 1.6±0.5, t=8.940, P<0.001). The areas under the ROC curves of umbilical artery PI, MCA-PI and CPR for predicting adverse perinatal outcomes were 0.71, 0.71 and 0.77, respectively. CPR had the highest sensitivity (0.74) compared with umbilical artery PI (0.68) and MCA-PI (0.71), but the specificity of them were similar (0.67, 0.66 and 0.66). Multivariate logistic regression analysis showed that only CPR was the independent risk factor for adverse perinatal outcomes ( OR=0.028, 95% CI: 0.010-0.080, P<0.001). Conclusions:As an indicator for early prediction of adverse perinatal outcomes of induction of labor in prolonged pregnancy, CPR was more sensitive but less specific.