BACKGROUND: It has been suggested that amniotic epithelial cells (AECs) express almost all of the markers of neural cell and secret a lot of neurotrophic factors and neurotransmitters. If AECs could substitute neural cells, its neurotrophic effect will bring promising prospect in treating neuron injuries and degenerative neural disease.OBJECTIVE: To detect specific proteins of neural cells in rat's cultured AECs.DESIGN: Repeated measurement design.SETTING: Second Clinical Medical College , Jilin University; Department of Histology & Embryology, School of Basic Medical Science, Jilin University.MATERIALS: This experiment was conducted at the Department of Histology & Embryology, School of Basic Medical Science, Jilin University from October 2004 to October 2005. The rat amniotic epithelial tissue was mechanically peeled from an embryonic 12 to 14days Wistar rats. Mouse anti Nestin was purchased from Chemicon Co.,and anti-ChAT rabbit anti-NSE and anti-NT-3 antibodies from Wuhan Boshide Company. Mouse anti-Musashi antibody was donated by Pro.Okano.METHODS: AECs were dissociated and purified from the amnion of pregnancy 12-14 day rats. AECs were treated with trypsin for 5 minutes,then cultured in DMEM/F12 medium at a humidified atmosphere of 0.05 volume fraction of CO2 in air at 37 ℃. Cells were inoculated at a concentration of 5×109 cells/L in culture flask. After 3 days, cells were inoculated onto poly-lysine-treated 35 mm culture Petri dish at a density of 1 × 108 cells/L for immunocytochemically staining. The cells were fixed with 40 g/L paraformaldehyde for 20 minutes. Immunocytochemical staining method was used to detect the expression of microtubule-associated protein-2 (MAP-2),neuron specific enolase(NSE), glial fibrillary acidic protein (GFAP) and choline acetyl transferase(ChAT).MAIN OUTCOME MEASURES: ① Morphological observation of rat'AECs at different culture time. ② Expression of specific protein of neural cells in rat' cultured AECs.RESULTS: ① After cultured for 24 hours, the AECs were flat and presented fibroblast-like morphology. 3 to 5 days later, cell bodies were well stacked; AECs had a big and round nucleus and were connected with each other by flourishing dendrites. ② Immunocytochemical staining results after culture for 4 days showed that AECs expressed Nestin, ChAT,NSE, Musashi, MAP-2, GFAP.CONCLUSION: AECs are homologous to neural cells in morphology, and it may be a new cell source to treat nervous system disease.

Objective To explore the risk factors influencing the prognosis of patients with acute poisoning by analysis of clinical data of 356 patients in order to provide the scientific evidence for planning therapeutic strategies in ICU.Methods The clinical data of 356 patients with acute poisoning were collected during the period from January 1,2005 through December 30,2009,and the clinical findings from close observation were filled into the tables of specially designed “ Clinical observation of acute poisoning patients”.Some risk factors of 356 cases with complete clinical data were studied by single-factor analysis and Logistic multiple regression,such as gender,age,mode and cause of poisoning,kind of poison agents,time elapsed from poisoning to admission into the hospital,time elapsed from poisoning to admission into ICU,length of hospital stay,cardiopulmonary resuscitation,mechanical ventilation,APACHE Ⅱ score.Results Three hundred fifty-six patients with complete data were divided into survival group (n =260) and death group (n =96).Univariate analysis showed the length of hospital stay (5.72 ± 4.37) d,APACHE Ⅱ score (10.27 ±7.77),time elapsed from poisoning to admission into ICU (17.16 ± 31.22)h in the survival group,and the length of hospital stay (3.53 ± 5.79) d,APACHE Ⅱ score (18.78 ±8.66),time elapsed from poisoning to admission into the ICU (37.21 ±67.35) h in the death group (P ＜0.05 or P ＜ 0.01).The differences in rates of CPR,mechanical ventilation and kind of poison agents between the two groups were statistically significant (P ＜ 0.05).Multivariate Logistic regression analysis revealed that the length of hospital stay,APACHE Ⅱ score,rates of cardiopulmonary resuscitation,mechanical ventilation and kind of poison agents were positively correlated with prognosis of patients with acute poisoning (P ＜ 0.05).Model to predict mortality was established:Y =-0.817-0.137X1 +0.140X3 + 2.133X4 + 1.039X5-0.291X6.Conclusions Hospital stay,APACHE Ⅱ score,cardiopulmonary resuscitation,mechanical ventilation and kind of poison agents were independent risk factors for predicting prognosis.APACHE Ⅱ score system and Logistic regression analysis can be used to evaluate the severity and prognosis of patients with acute poisoning.

BACKGROUND: It has been suggested that amniotic epithelial cells (AECs) express almost all the markers of neural cell and secrete biologically active neurotrophins such as brain derived neurotrophin factor (BDNF) and neurotrophin-3 (NT3).If AECs can substitute neural cells, its neurotrophic effect will bring expansive prospect in treating spinal cord injuries and degenerative neural disease.OBJECTIVE: To observe the survival, migration and secretory function of AECs after transplanted into the injured spinal cord.DESIGN: An observational experiment.SETTING: Department of Histology and Embryology, School of Basic Medical Science, Jilin University.MATERIALS: Embryonic rat of 12-14 days (n =1) and adult Wistar rats (n =18, 300-350 g) were provided by the Experimental Animal Center of Jilin University. Immunohistochemical reagents: Mouse anti-rat BrdU monoclonal antibody was bought from Sigma Company. Rabbit anti-rat NT3 polyclonal antibody and rabbit anti-rat BDNF polyclonal antibody were bought from Boster Company. SP immunohistochemistry reagents were purchased from Maixin Company.METHODS: The experiment was made in the Department of Histology and Embryology, Basic Medical Science of Jilin University from July to October 2005. ① Wistar rats were anesthetized by intraperitoneal injection of chloral hydrate, subcutaneous tissue and muscle were separated, spinous process and lamina of vertebra were removed by bone ribbing rongeur. to expose the spinal cord. The spinal cords were clamped at the twelfth thoracic vertebra (T12) for 3 minutes.After surgery, the wounds were smeared with penicillin G, then muscle and skin were sutured. The rats were anesthetized by inhaling ether if necessary. ② Obtaining and culture of AECs: Amniotic membrane was peeled from the placenta of a pregnant Wistar rat of 12-14 days. The amnictic membrane was dissected into small pieces of 1 mm×1 mm×1 mm, then digested and cultured, and mechanically made into single cell suspension, finally plated in bottles. ③ Transplantation of AECs into injured spinal cord: The initial wound was slit and injected with 5 μL Brdu labeled AECs (1×1012 L-1) to the exposed injured spinal cord at 3.0 mm anterior to the injured site. The injections were made at a rate of 5 μL per 3 minutes with a microsyringe. The syringe was slowly pulled out after 5 minutes, then muscle and skin were sutured. ④ Sampling and immunohistochemical analysis: Three animals were sacrificed at 1 week and the other three at 2 weeks postoperatively. The sections were fixed with 40 g/L paraformaldehyde in phosphate buffer solution (PBS) for 20 minutes at room temperature, followed by incubation with primary antibodies at 4 ℃ overnight. The samples were treated with secondary antibodies, biotinylated anti-mouse or rabbit immunoglobulin (IgG) at 37 ℃ for 20 minutes; Followed by incubation of horseradish peroxidase (HRP) labeled third antibodies at 37 ℃ for 20 minutes, then stained with 0.2 g/L diaminobenzidine (DAB) or AEC.MAIN OUTCOME MEASURES: Survival, migration and expression of AECs after transplanted into the injured spinal cord. RESULTS: After transplantation, most of the AECs gather beneath the pia mater of injured spinal cord at 1 week. But they migrated more extensively and many positive nuclear cells (brown) were observed in the center cannel and surrounding gray mater. Meantime, it was also detected that the transplanted AECs could express NT3 (positive cells stained as red) and BDNF in the injured spinal cord.CONCLUSION: AECs could survive for at least 3W after transplanted into the injured spinal cord of adult rats and could migrate widely; Furthermore, they could secrete neurotrophic factors such as NT-3 and BDNF.