Problem-based learning(PBL) was applied in probation of 2002 grade with satisfactory results.It can inspire students' interest,improve their synthetic analyzing,self-thinking,self-study innovative ability,and make studerts graspe well theoretical and practical learning methods.It is important to cultivate their ability of synthetic analyzing and deepen the teaching reform.

Objective To investigate the effects of intestinal ischemia-reperfusion(I/R)on cerebral microglial activation in rats.Methods One hundred and twenty-eight healthy male SD rats weighing 250-300 g were randomly allocated to one of two groups(n =64 each):group sham operation(group S)and intestinal I/R group.Intestinal I/R was produced by occlusion of superior mesenteric stery for 90 main followed by reperfusion.Sixteen animals were sacrificed at each of the 4 time points:2,6,24 and 48 h of reperfusion in each group.Their intestines were obtained for microscopic examination.Their brains were harvested for detection of microglial activation (by immuno-histochemistry).The reactive oxygen species(ROS),MDA and NO contents and SOD,nitric oxide synthase(NOS)and inducible nitric oxide synthase(iNOS)activities in the brain were measured.Results The microglia were in quiescent condition.Ibal staining was negative or light in group S.Intestinal I/R significantly increased intestinal Chiu score,cerebral microglial activation at 6,24 and 48 h of repeffusion which peaked at 24 h of reperfusion in group I/R as compared with group S.Cerebral ROS,MDA,NO levels and NOS,iNOS activities were significantly higher while SOD activity was significantly lower in group I/R than in group S.Concluslon Intestinal I/R can activate microglia and induce the release of nitrogen and oxygen free radicals resulting in cerebral injury.

On the basis of pre-experiment research and the hypothesis of“amputated lumbricus”, this research was aimed to explore mechanism of active components of the amputated lumbricus to promote wound healing. Skin excision was used to establish the mice model. The amputated lumbricus extract was prepared. HE staining and immunohistochemistry techniques were used in the determination of the wound healing rate and changes of VEGF, bFGF, TGF-β1 expression during wound healing period. The results showed that compared with the blank control group, the healing rate of the amputated lumbricus extract group was better. And the HE staining showed better improvement of traumatic tissues. There was no statistic differences on the expression of VEGF and TGF-β1 between the amputated lumbricus extract group and the normal saline group (P> 0.05). The expression of bFGF in amputated lumbricus extract group reached peak earlier than the control group and also lasted a longer time. The amputated lumbricus extract group reached peak on the first day, which had a significant difference (P < 0.05) compared with the control group at the same timepoint. It was concluded that the external application of amputated lumbricus extract had wound healing effect on traumatic skin of mice. Its mechanism may be irrelevant to the expression of VEGF and TGF-β1. However, it may be related to the increasing of bFGF expression in the injured regions during the inflammation stage and proliferation stage.

A cold-adapted (ca), temperature sensitive (ts), live attenuated influenza B virus strain B/Ann Arbor/1/66 was chosen for influenza virus rescue research, in which six internal gene segments, PB1, PB2, PA, NP, M, NS, were fully synthesized and nine amino acid substitutions were artificially alter by human intervention. The resultant B/Ann Arbor/1/66 plasmids were named as pAB121-PB1, pAB122-PB2, pAB123-PA, pAB124-HA, pAB125-NP, pAB126-NA, pAB127-M and pAB128-NS, respectively. A recombinant influenza A virus was previously generated entirely from cloned cDNA. An infectious recombinant influenza B virus was generated here, and designated as rMDV-B, by plasmid-based reverse genetics. The rMDV-B virus contained HA and NA genes from an epidemic influenza B vires strain B/Malaysia/2506/2004 in the background of internal genes derived from influenza B virus strain B/Ann Arbor/1/66. HA titer of rMDV-B in MDCK cells and embryonated chicken eggs ranged from 1 : 64 to 1 : 512. The results may allow an effective live influenza B vaccine to be produced from a single master strain, providing a model for the design of future live human influenza vaccines.

Objective:To examine the expression of transforming growth factor I(TGF-β1) and bone morphogenetic protein-9 (BMP-9) in human nonunion tissues,and to evaluate the clinical significance.Methods:The number of hypertrophic nonunion tissue samples and atrophic nonunion tissue samples were collected from Department of Orthopedics,the Second Xiangya Hospital of Central South University and Suzhou Kowloon Hospital Affiliated to School of Medicine of Shanghai Jiao Tong University between 2010 and 2014.Semi-quantification of SP immunohistochemical method and pathological image analysis software IPP6.0 were used to analyze the expression of TGF-β1 and BMP-9.Nonunion type,patients' age and nonunion time were statistical analyzed.Results:The absorbance values of TGF-β1 and BMP-9 in the hypertrophic nonunion tissues were 0.3236±0.0390 and 0.1337±0.0400,respectively;while the absorbance values of TGF-β1 and BMP-9 in the atrophic nonunion tissues were 0.3191±0.0369 and 0.1373±0.0423,respectively,with no significant difference between the two types of tissues (both P＞0.05).There was also no significant difference in patients' age and bone nonunion time between them (all P＞0.05).Conclusion:There is no significant difference in osteogenic potential between the hypertrophic nonunion tissues and the atrophic nonunion tissues.

Objective:To explore the utility of applying low frequency transcranial magnetic stimulation (rTMS) in the acute stage of ischemic stroke in terms of improving upper limb motor function.Methods:Eighty ischemic stroke survivors in the acute stage were randomly divided into a control group and an experimental group, with 40 in each. In addition to routine rehabilitation, the experimental group was given low frequency rTMS, while the control group was provided with sham rTMS. Before and after 4-weeks of treatment, upper limb motor function was evaluated using the Fugl-Meyer rating scale (FMA), Wolf motor function tests (WMFTs), the modified Barthel index (MBI) and in terms of motor evoked potential (MEP) latency and amplitude.Results:There were no significant differences between the two groups before the treatment. Afterward, however, the average FMA, WMFT, MBI scores had improved significantly more in the experimental group, on average, as had the average MEP amplitude.Conclusion:Low frequency rTMS in the acute phase of ischemic stroke can improve upper limb motor function and ability in the activities of daily living.

Objective:To analyze the clinical efficacy and prognostic factors of comprehensive treatment for atypical teratoid / rhabdomyoma tumor (AT/RT).Methods:Clinical data of children diagnosed with AT/RT who underwent radiotherapy in Department of Oncology of Xinhua Hospital affiliated to Shanghai Jiao Tong University School of Medicine from November 2012 to September 2022 were retrospectively analyzed. Pearson Chi-square test or continuous-corrected Chi-square test or Fisher's exact probability method were used for inter-group comparison of categorical variables. Independent sample t-test or Wilcoxon rank-sum test were used for inter-group comparison of continuous variables. Kaplan-Meier method was used to calculate the 1-year and 2-year overall survival (OS) rate and progression free survival (PFS) rate. Univariate and multivariate Cox regression analyses were employed to determine relevant prognostic factors. Results:A total of 45 patients were included, with a male/female ratio of 1.65:1, including 27 children aged ≥3 years old. All patients received surgery and radiotherapy in which 39 patients received chemotherapy, 41 craniospinal irradiation (CSI), and 4 whole brain or focal radiation therapy. The median follow-up was 28 (13.5, 49) months. A total of 14 patients died after comprehensive treatment. The 1-year OS rate was 80.0% and the PFS rate was 71.1%. The 2-year OS rate was 75.5% and the PFS rate was 65.7%. Survival prognostic analysis showed negative imaging assessment after radiotherapy ( HR=0.087, 95% CI: 0.011-0.697, P=0.022) was a favorable factor for PFS. The primary tumor<4.8 cm ( HR=0.221, 95% CI: 0.052-0.935, P=0.040) and CSI ( HR=0.085, 95% CI: 0.011-0.651, P=0.018) were favorable factors for OS. In subgroup analysis, CSI also improved OS in children aged ≥3 years ( HR=0.014, 95% CI: 0-0.470, P=0.017), but there was no significant difference in PFS. In children without cerebrospinal fluid dissemination, negative radiographic results after radiotherapy ( HR=0.066, 95% CI: 0.009-0.481, P=0.007; HR=0.076, 95% CI: 0.008-0.695, P=0.024, respectively) and CSI (HR=0.105, 95% CI: 0.012-0.937, P=0.044; HR=0.054, 95% CI: 0.005-0.629, P=0.020, respectively) were favorable factors for PFS and OS in children, and the primary tumor<4.8 cm also suggested a longer OS ( HR=0.094, 95% CI: 0.013-0.690, P=0.020). Conclusions:Comprehensive treatment including radiotherapy improves clinical prognosis of children with AT/RT. Our study shows that negative imaging results after radiotherapy are associated with PFS improvement. The primary tumor<4.8 cm and CSI are favorable factors for OS. CSI is also a significantly positive prognostic factor in children aged ≥3 years and those without cerebrospinal fluid dissemination.

Objective:To explore the ability of sequential immunization regimen inducing neutralizing antibodies against severe acute respiratory syndrome coronavirus 2(SARS-CoV-2) Wuhan-Hu1 and Omicron variants in mice.Methods:Groups of 6-8-week-old BALB/c mice were primed with two doses of Wuhan-Hu-1 inactivated vaccine, and then boosted with Omicron or Wuhan-Hu-1 inactivated vaccine, respectively. Binding antibodies were tested by enzyme linked immunosorbent assay; and neutralizing antibodies against Wuhan-Hu1 and Omicron variants were analyzed by vesicular stomatitis virus pseudovirus assay system; SARS-CoV-2 specific cellular immune responses were quantified by enzyme-linked immunosorbent spot assay.Results:IgG antibodies against Wuhan-Hu1, Delta and Omicron RBD were enhanced after the second dose of Wuhan-Hu1 inactivated vaccine. Compared with Wuhan-Hu1 inactivated vaccine, the group boosted with Omicron inactivated vaccine improved Wu-RBD and Omic-RBD specific IgG antibodies 1.41 and 1.26 times, and serum neutralizing antibodies against BA.1, BA.2, BA.4/5 and BF.7 were elevated 4.5, 3.4, 12.1 and 6.5 folds, respectively, by sequential immunization. After booster immunization with inactivated Wuhan-Hu1 or Omicron vaccines, Wu-RBD IgA titer was significantly higher than that of one dose inactivated Wuhan-Hu1 vaccine ( P=0.005 7, P=0.006 1). Conclusions:Neutralizing antibodies against Omicron variants were enhanced by sequential immunization with Omicron inactivated vaccine. Specific IgA was significantly enhanced after the third dose of inactivated vaccine.

【Objective】 To investigate the situation of carbapenem-resistant Enterobacteriaceae(CRE) colonization in patients undergoing haploidentical hematopoietic stem cell transplantation (haplo-HSCT). 【Methods】 A total of 241 consecutive patients who underwent haplo-HSCT in the First Affiliated Hospital of Soochow University from June 1, 2021 to June 1, 2022 were enrolled. Anal swab screening was performed within 48 hours of admission and blood cultures were taken when the patient developed fever. Univariate and multivariate analysis were used to analyze the colonization rate, distribution, risk factors and the correlation between CRE colonization and post-transplant bloodstream infection(BSI). 【Results】 Among 241 patients with haplo-HSCT, there were 90 cases in CRE colonization positive group, with a colonization rate of 37.3% (90/241). Multivariate logistic regression analysis showed that sex (OR 2.42, 95% CI 1.38-4.22, P<0.05) and history of infection within 30 days before transplantation (OR 3.37, 95% CI 1.59-7.17, P<0.05) may be independent risk factors for CRE intestinal colonization. Of the 95 CRE strains, the top five species were carbapenem-resistant Klebsiella pneumoniae (38/95, 40.0%), carbapenem-resistant Escherichia coli (29/95, 30.5%), carbapenem-resistant Enterobacter cloacae (13/95, 13.6%), carbapenem-resistant Klebsiella acidophilus (6/95, 6.3%) and carbapenem-resistant Proteus mirabilis (3/95, 3.1%). The incidence of post-transplant BSI was 12.0% (29/241) in the CRE-colonized group and 3.3% (8/241) in the non-colonized group. In the colonization group, 100% of the pathogens of BSI were identical with those of CRE colonization. 【Conclusion】 Bacterial culture of anal swab during haplo-HSCT is helpful for detection of CRE colonization in intestinal tract, which provides some clinical basis for active monitoring of key flora, prevention and control of infection.