2.Effect of maternal deprivation on learning and memory ability and hippocampal nerve regeneration in rats with hypoxic-ischemic brain damage
Yafei LI ; Liqun LU ; Qiongxian DENG
Chinese Journal of Applied Clinical Pediatrics 2016;(2):146-149
Objective To observe the effect of maternal deprivation(MD)on learning and memory ability and hippocampal pathology and nestin expression in rats with hypoxic -ischemic brain damage (HIBD).Methods The models of HIBD SD male rats were established by the method of Rice,and were randomly divided into 2 groups:MD group and control group.In addition,the sham -operation group(sham group)models were established.The MD group rats were separated from their mother 3 hours per day from the second day after modeling to the 21 st postnatal day.After 28 postnatal days,Morris water maze was used to evaluate the learning and memory ability of the rat models.HE stai-ning was employed to observe the hippocampal pathological change in the rats.Then,the expression of nestin in the hip-pocampus was measured by the method of immunohistochemistry.Results Their body mass changes showed that quali-ty of sham group was higher than that of the control and the MD groups,and quality was improved in the control group, compared with the MD group,and the differences were statistically significant(q =9.860 8,3.880 7,5.980 1 ,all P <0.05).The water maze scores of the MD group in place navigation test and spatial probe test were much lower than that of the control group and the sham group,and the scores of the sham group were higher than that of the control group,the differences were statistically significant(all P <0.05 ).The findings of HE stain showed that the pathology in the right -sided hippocampus of the sham group was normal and neurons were well -arranged,and that of control group was minimally abnormal,and the neurons were almost arranged orderly and remained normal.While,the pathomorpholo-gy of the MD group was obviously abnormal,the neurons were arranged disorderly,many of the neurons lost.According to the immunohistochemical findings,the number of nestin -positive cells in right -sided hippocampus of the MD group was significantly less than that of the control group,and the number of nestin -positive cells of the sham group was less than that of the MD group,which showed significant differences among the groups(all P <0.05).Conclusions MD aggravated injury to learning and memory ability of neonatal rats with HIBD,and decrease the number of nestin -posi-tive cells of MD markedly,which is not good for the recovery of brain injury.
3.Biological properties of C57BL/6 mouse embryonic fibroblasts and preparation of feeder layers
Ying LI ; Yafei GONG ; Xinjie CHEN
Chinese Journal of Tissue Engineering Research 2014;(11):1737-1742
BACKGROUND:Kunming mouse embryonic fibroblasts are the most common feeder layers at present, and there are rare reports addressing C57BL/6 mouse embryonic fibroblasts as feeder layers.
OBJECTIVE:To separate and culture C57BL/6 mouse embryonic fibroblasts in vitro, and produce feeder layers to enlarge the resources of mouse embryonic fibroblasts.
METHODS:C57BL/6 mouse embryonic fibroblasts were isolated and cultured by trypsin digestion method in vitro. The biological characteristics and growth rule of the fibroblasts were investigated, then the feeder layers for the cel culture were produced. The growth of cel colonies on the prepared feeder layer was tested.
RESULTS AND CONCLUSION:C57BL/6 mouse embryonic fibroblasts grew wel with a large amount, by trypsin digestion method at different concentrations. There was no significance in the survival rate after cryopreservation for 1 week, 2 weeks, 1 month, 3 months and 6 months. The cel s were proliferative from the second to fifth passage and declined sharply after the sixth passage. The planted mouse embryonic fibroblasts feeder layers had a high activity within 3 days, but got a sharp decline after 4 days. So it is best to use C57BL/6 mouse embryonic fibroblast feeder layers within 3 days after they’re inactivated. C57BL/6 mouse embryonic fibroblast feeder layer can support embryonic stem cel s and induce pluripotent stem cel s to grow as Kunming mouse embryonic fibroblasts.
4.Treatment of avascular necrosis of femoral head by implanting a composite of autogenous bone marrow and noncelluar tissue engineered bone allograft with BMP
Yafei LI ; Hongxing CHANG ; Jianhua YAO
Chinese Journal of Orthopaedics 2001;0(06):-
Objective To investigate the effect of treatment of avascular necrosis of femoral head in adolescence by implanting a composite of autogenous bone marrow, bone morphogenetic protein(BMP), and noncelluar tissue engineered bone allograft. Methods The BMP was partially purified from bovine cortical bone (bBMP) by Urist method. The bone allograft chips were mixed with bBMP and bone marrow. The composite was implanted into the necrotic area of the femoral head after core decompression, then partial deminerallized allograft fibula segments were inserted in the core decompression holes to support the necrotic area in preventing the collapse in 64 adolescent patients (78 hips). Results 55 cases (67 hips) were followed up for 3 months to 6 years(mean 44 months). 28 case(36 hips) in FicatⅠ,Ⅱ were followed up over 3 years, of whom there were no obvious pain and dysfunction in 18 cases(22 hips), high density new bone was shown in core decompression area in CT scanning, and no evidence of progressive necrosis. There was no worsening of the symptoms in 4 cases(6 hips) in Ficat Ⅰand Ⅱ, but the lesion progressed. In 6 cases (8 hips) in Ficat Ⅲ, there were no obvious pain and dysfunction in 2 cases, but 4 cases underwent total hip replacement because of persistent pain and progressive lesion. Conclusion The partial demineralized allograft fibula can provide direct mechanical support to prevent the necrotic femoral head from progress and collapse, autogenous bone marrow and BMP is able to promote new bone formation. The method can be used as an alternative for the treatment of osteonecrosis of femoral head at stage Ⅰ,Ⅱ.
5.Disinfection efficacy of SZ herbal disinfectant on bacterium and virus in suspension
Bin XU ; Li LI ; Yan XU ; Yafei LI
Journal of Third Military Medical University 2003;0(09):-
Objective To determine the main components of SZ herbal disinfectant and to observe its inactivation efficiency on microorganism in suspension. Methods The spectrophotometer examination, neutralizer screening trial, bacteria count trial, phage plaque count trial and cells infection test had been used to determine contents of ursolic acid in SZ herbal disinfectant and the disinfection efficacy. Results The ursolic acid contents in original SZ disinfectant reached 436.43 ?g/ml and decreased by 8.07% after a year of deposit. Treated by disinfectant for 5 min and 1∶5 dilution solution for 10 min, the Staphylococcus aureus (SA) and Escherichia coli (EC) in suspension could be killed with the efficiency of 100%. Treated with SZ disinfectant and the dilution solution (1∶50) respectively, the Candida albicans could be killed with the efficiency of 90.97% and 51.10%. Treated with the dilution solution for 3 min, the f2 bacteriophage and PV could be reduced by 100% and 9.00 log. Conclusion With the main component of ursolic acid, the SZ herbal disinfectant is a kind of natural disinfectant. It has a satisfactory inactivation efficacy on bacterial vegetative form and virus.
6.Effect of Dexamethasone on LC3 expression of neurons in cerebral cortex of juvenile rats with sepsis
Dongqiong XIAO ; Yafei LI ; Xin YANG ; Yi QU ; Xihong LI
Chinese Journal of Applied Clinical Pediatrics 2016;31(6):421-424
Objective To investigate the effect of Dexamethasone on microtubule - associated protein 1 light chain 3(LC3)expression of cells and neurons in cerebral cortex of juvenile Wistar rats with sepsis. Methods Models of juvenile Wistar rats with sepsis were established through cecal ligation and puncture(CLP). Totally 60 cases of 30 -day - old juvenile male Wistar rats were randomly divided into sham - operation group(10 cases),non - treated group (25 cases)and Dexamethasone group(25 cases). Twelve hours after CLP,rats in Dexamethasone group were injected with Dexamethasone(1 mg / kg)via tail vein every other day,with a total of 3 times. The same dose of saline was used in the non - treated group. All rats were killed at the age of 40 days. Expressions of LC3 and neuronal nuclei(NeuN)of cells in cerebral cortex of rats were detected by using immunofluorescence assay,and the number of positive cells was calculated by using image analysis system software. Expressions of LC3 - Ⅰ and LC3 - Ⅱ protein were measured by a-dopting Western blot. Results Three hours after CLP,rats appeared to be curled up and showed piloerection and shi-vering and the neurobehavioral score in non - treated group was significantly lower than that in sham - operation group (t = 9. 895,P = 0. 000). Twelve of 25 rats in Dexamethasone group died in 10 days after CLP(48% ),while 8 of 25 rats in non - treated group died(32% ),and the difference was not statistically significant between the 2 groups(χ2 =1. 333,P = 0. 248). The immunofluorescence staining and image analysis showed the percentage of LC3 positive cells in non - treated group was significantly increased(0. 606 7 ± 0. 030 1 vs 0. 353 3 ± 0. 025 8,t = 15. 644,P = 0. 000;0. 606 7 ± 0. 030 1 vs 0. 270 3 ± 0. 019 4,t = 22. 450,P = 0. 000). In non - treated group,the LC3 expression of cells in the cerebral cortex of rats was up - regulated,and the LC3 - Ⅱ/ LC3 - Ⅰ ratio was significantly higher than that in sham operation group and Dexamethasone group(0. 413 3 ± 0. 022 5 vs 0. 205 0 ± 0. 015 2,t = 18. 802,P = 0. 000;0. 413 3 ± 0. 022 5 vs 0. 185 0 ± 0. 023 5,t = 17. 206,P = 0. 000). The LC3 positive neurons in the cerebral cortex of rats were less in sham operation group and Dexamethasone group. The LC3 positive neurons were more in non - treated group than that in sham operation group and Dexamethasone group(0. 580 0 ± 0. 020 0 vs 0. 298 3 ± 0. 014 7,t =27. 783;P = 0. 000;0. 580 0 ± 0. 020 0 vs 0. 261 7 ± 0. 017 2,t = 28. 614;P = 0. 000). Conclusions The LC3 expres-sion of cells in the cerebral cortex of juvenile Wistar rats with sepsis was up - regulated,LC3 - Ⅱ/ LC3 - Ⅰ ratio in-creased,and the number of LC3 positive neurons also increased,while Dexamethasone could have inhibitory effect on them.
7.Curcumin for propranolol-induced psoriasis-like lesions in guinea pigs: evaluation of therapeutic efficacy and effects on proliferating cell nuclear antigen expression
Zhengsheng YANG ; Li LI ; Yafei WANG ; Huijun YANG
Chinese Journal of Dermatology 2015;48(3):175-178
Objective To estimate the influence of curcumin on psoriasis-like lesions and proliferating cell nuclear antigen (PCNA) expression in guinea pigs,so as to investigate the therapeutic effect and mechanism of curcumin in psoriasis.Methods A model of psoriasis-like skin inflammation was established by applying propranolol 5% cream (4 times a day for 3 weeks) to the dorsal skin of ears of 30 guinea pigs,which were then equally classified into 5 groups:model group receiving no treatment,observation group receiving no treatment but observation for 2 weeks,model control group treated with intragastric 25% polyethylene glycol solution (1 rnl once a day) for 2 weeks,low-dose and high-dose curcumin groups treated with intragastric curcumin solution at 20 and 40 mg/kg per day respectively once a day for 2 weeks.Six guinea pigs receiving neither induction by propranolol nor treatment by curcumin or polyethylene glycol solution served as the normal control group.Skin specimens were harvested from the ears of guinea pigs in the normal control group after three weeks of breeding,in the model group immediately after the establishment of psoriasis-like model,in the observation group after 2 weeks of observation,and in the other 3 groups after 2 weeks of treatment.Subsequently,haematoxylin-eosin (HE) staining was conducted to observe histopathologic changes,and immunohistochemical assay to detect the expression of proliferating cell nuclear antigen (PCNA).Results Gross observation of the skin revealed that curcumin attenuated psoriasis-like skin manifestations in guinea pigs.There were significant differences in histopathologic scores (F=296.14,P< 0.01) and PCNA expression rate among the 6 groups (F =108.49,P < 0.01).Least significant difference (LSD) test showed that both histopathologic scores and PCNA expression rate were significantly higher in the model group than in the normal control group (6.42 ± 0.49 vs.0.92 ± 0.20,63.17% ± 5.47% vs.20.83% ± 2.99%,both P < 0.01).After 2 weeks of treatment,both low-dose and high-dose curcumin groups showed significantly lower histopathologic scores (4.25 ± 0.27 and 1.75 ± 0.42 vs.6.42 ± 0.49,both P< 0.01) and PCNA expression rate (43.50% ± 2.90% and 25.50% ± 3.74% vs.63.17% ± 5.47%,both P < 0.01) compared with the model group.Conclusion Curcumin can attenuate pathological manifestations of psoriasis-like lesions,and downregulate PCNA expression in guinea pigs.
8.A case-control study on risk factors for intrauterine HBV infection
Xiang LI ; Chao HU ; Taiwu WANG ; Yao ZHANG ; Yafei LI
Chongqing Medicine 2017;46(16):2187-2189,2192
Objective To explore the risk factors for hepatitis B virus (HBV) intrauterine infection to provide a scientific ev idence for itsprevention.Methods Three hundred and twelve pregnant women of HBsAg positive screened from April 2013 to May 2015 served as the research subjects and were followed up until 6 months after birth.The infantile mothers of HBsAg and/or HBV DNA positive were selected as the intrauterine infection case group,while other mothers served as the control group.The Logistic regression analysis was adopted to analyze the risk factors for intrauterine HBV infection.The questionnaire survey method was used to collect the basic data and time-resolved immunofluorescence assay was used to detect HBsAg.PCR was adopted to measure level of HBV DNA and automatic biochemistry analyzer was used to measure the hepatic functional parameters including ALT,AST,triglyceride and cholesterol.Results The single factor analysis results indicated that HBeAg,HBV DNA,contamination of amniotic fluid and sexual behavior during pregnancy were related to HBV intrauterine infection(P<0.05).The multiple variate Logistic regression results showed that positive HBeAg(OR=2.76,95 % CI=1.19-7.94),positive HBV DNA(OR=9.62,95 % CI=2.58-35.33),and sexual behaviors during pregnancy (OR =1.53,95 % CI =1.07-6.40) were the risk factors for intrauterine HBV infection.Conclusion Pregnant women with positive HBeAg,positive HBV DNA and sexual behavior during pregnancy may be the high risk factors for neonatal intrauterine HBV infection.
9.Study on perceived fatigue evaluating model during simulated load carriage.
Jiewen ZHENG ; Yuhong SHEN ; Chenming LI ; Yafei GUO ; Pengfei REN
Chinese Journal of Industrial Hygiene and Occupational Diseases 2015;33(6):444-447
OBJECTIVETo establish a perceived fatigue evaluating model during simulated load carriage that is based on objective variables through analyzing the characteristics and trends of shoulder force, shoulder pressure, waist pressure, back pressure, and perceived fatigue, and to provide an analytical technique for research on load carriage.
METHODSA 50-min simulated walking (at a speed of 5 km/h and a slope of 0%) experiment including 14 healthy male adults was conducted under four levels of backpack payloads (25, 29, 34, 37 kg). Shoulder force and trunk pressure were sampled simultaneously and analyzed with time- and frequency- domain methods. Multivariable linear regression was used to build a perceived fatigue evaluating model during load carriage.
RESULTSThe perceived fatigue evaluating model based on shoulder force, trunk pressure distribution ratio, load, and body mass index (BMI) was established. Its adjusted determination coefficient (aR2) was 0.709 and the absolute percentage error (APE) at the end of the experiment was less than 20%. The goodness of fit of the model based on frequency-domain independent variables was much higher compared with the model based on time-domain independent variables. The addition of BMI that represents the individual differences to the model obviously improved the goodness of fit.
CONCLUSIONThe perceived fatigue evaluating model established in this study does not rely on the physiological changes of individuals, and thus can be used to establish an evaluation system for human load carriage with dummy as a substitution for human in experiments and to provide a scientific basis for efficient human load carriage.
Adult ; Fatigue ; Humans ; Male ; Models, Theoretical ; Pressure ; Walking ; Weight-Bearing
10.Exploration of the regulation site of HIF-1α in Notch signaling pathway in the hippocampus of rats with status ;epilepticus
Yafei ZHUANG ; Lin ZHANG ; Baoqiang YUAN ; Yuanyuan DAI ; Rui LI
Journal of Clinical Pediatrics 2016;34(7):544-548
Objective To study the expression of hypoxia inducible factor-1 (HIF-1 ) and Notch signaling pathway downstream gene HES 1 in the hippocampus of pubertal rats with status epilepsy (SE), and to explore the regulation site of HIF-1αin Notch signaling pathway. Methods One hundred and seventy-six 21-day-old SD rats were randomly divided into control group (NS group), pentetrazole (PTZ)-induced SE group (PTZ group), and Notch signaling pathway speciifc inhibitor (DAPT) intervention group (DAPT group). In PTZ group PTZ was intraperitoneally injected to build SE model and in NS group normal saline was injected as control. The intraperitoneal injection of diazepam was used to terminate SE seizures. After successful modeling, the bilateral hippocampuses were isolated after the rats were sacriifced at 0.5, 1, 2, 4 and 8 h, respectively, and RT-PCR was performed to detect the mRNA expression of HES 1 and HIF-1α. The Western Blot was performed to detect protein expression in hippocampuses which were collected at 2 , 4 , 8 , 12 , and 24 h after successful modeling. DAPT group received intraperitoneal injection of DAPT 30 min before the start of molding, then the hippocampuses were isolated at 2 and 8 h after successful modeling. RT-PCR was performed to detect the mRNA expression of HES 1 and HIF-1αat 2 h, and Western blot was performed to detect protein expression at 8 h. Results At each time point after SE, the expression of mRNA of HES 1 and HIF-1αand the expression of protein were higher than the same time point of NS group (P0 . 05 ). Compared with the same time point of PTZ group, the mRNA expression of HES 1 and HIF-1αand the expression of protein of DAPT group were obviously reduced (P0 . 05 ). Conclusion HES 1 gene may be the regulatory site of HIF-1 expression in Notch signaling pathway in the hippocampus of puberty rats with SE.