Objective To establish a model in rats for studying the lung injury induced by powder combustion. Methods The explosion box and trauma chamber were constructed based on the fire simulation-platform. The smoke composition was analyzed on-line. The animal clinical manifestation was observed, and the lung water ratio, arterial blood gases, gross appearance and macropathology were analyzed to evaluate the injury level. Results The smoke contents included CO, SO 2, NO and NO 2. When the injury occurred, the CO concentration was 505 23 ppm, and SO 2 concentration was 67?4.8ppm. The time to cause injury was 4 minutes. The tachypnea immediately occurred for most of the rats, then bradypnea and dyspnea. The metabolic acidosis happened at the early stage of injury and the combined effects of metabolic acidosis and respiratory acidosis appeared at the late stage. Water ratio in the lung gradually increased and reached the peak at 6 hours later, and the normality was not recovered after 24 hours. The gross appearance and macropathology proved the lung injury. The obvious bleeding appeared at 4 hours, and the edema reached the most grievous level at 6 hours, and the normality was not recovered after 24 hours. Conclusion The model has been successfully established to study powder combustion-induced acute aspiration lung injury in rats .This model can keep the injury conditions stably and has the benefits of easy-making and repeatable.

Objective To study the association between the CTLA-4 gene polymorphism and Graves disease.Methods A total of 120 unrelated patients with Graves disease southern Han nationality of China were recruited from clinics in the Department of Endocrinology and Metabolism,the First Affiliated Hospital of Sun Yat-sen University from 2001 to 2003.Ethnically matched 123 control subjects with no history of autoimmune disease were from Guangdong.We investigated the polymorphism of the cytotoxic T lymphocyte antigen 4 gene on chromosome 2q33.1 microsatellite markers of CTLA4 were chosen,this was done by PCR amplification of marker sequences using fluorescently labeled primers and subsequent analysis of the PCR products on ABI prism 377.Results Twenty alleles were observed in the population,with sizes ranging from 84 to 144 bp.There was no significant difference when compared with controls in the distribution of the genotypes(?2=21.428,P=0.208).This investigation indicated that the gene of CTLA4 was not susceptible gene for Graves disease.Conclusion This study suggests that CTLA4 gene may not be susceptible gene to Graves disease for the Chinese southern Han population.

In this study, calcium phosphate cements (CPC) were prepared by mixing cement powders of tetracalcium phosphate (TTCP) with a cement liquid of phosphate acid saline solution. Tetracycline (TTC)-CPC, chitosan-CPC and chitosan-TTC-CPC were investigated with different premixed schedule. It was demonstrate that both TTC and chitosan worked on the phase transition and crystal characteristics. TTCP mixed with phosphate acid saline solution had similar features of Fourier transform-infrared spectrometry (FT-IR) no matter it was mixed with chitosan or TTC or both. TTC premixed with cement liquid or powder had significant different features of FT-IR and 876 cm(-1) seemed to be a special peak for TTC when TTC was premixed with cement liquid. This was also supported by XRD analysis, which showed that TTC premixed with cement liquid improved phase transition of TTCP to OCP. Chitosan, as organic additive, regulates the regular crystal formation and inhibits the phase transition of TTCP to OCP, except when it is mingled with cement liquid premixed with TTC in field scanning electron microscope. It was concluded that the premixed schedule influences the crystal formation and phase transition, which may be associated with its biocompatibility and bioactivities in vivo.

strains that could produce raw starch-digesting glucoamylase were isolated from soil and mildewed rice.The highest raw starch-digesting glucoamylase activity strain named OR-1 was identified as Rhizopus.sp.The raw starch-digesting glucoamylase activity of the strain is 90U/mL.Through UV and NTG mutagenesis,the raw starch-digesting glucoamylase activity raised to 200U/mL and 325U/mL respectively.The RDA were 70% and 65% respectively.

Aim To express the fusion protein hTNFα -hPgnK5 in E.Coli and to identify its activity. Methods The hTNFα -hPgnK5 gene express vector was constructed and the fusion protein was expressed in E.coli. The activity of fusion protein to inhibit the proliferation of tumor cells or angioendothelial cells in vitro was determined by MTT. Results Fusion protein hTNFα -hPgnK5 possessed immunoactivity in Western blot analysis and could inhibit proliferation of tumor cells or angioendothelial cells in vitro test. Conclusion The hTNFα gene and hPgnk5 gene can be coexpressed in prokaryotic system and expression products can inhibit the proliferation of tumor cells or angioendothelial cells in vitro.

Objective To investigate the left ventricular (LV) torsion parameters of type B WolffParkinson-White syndrome (B-WPW) and to explore alternation of the left ventricular motion pattern in patients with B-WPW.Methods Thirty-eight patients with B-WPW were studied.And 40 volunteers were selected as control.Two-dimensional speckle tracking imaging (2D-STI) was used to acquire left ventricular torsion parameters,including peak value and time to peak value of LV twist,LV apex rotation,and LV base rotation.Apical-basal rotation delay (RDA-B) was calculated.Biplane Simpson method was used to measure LV end-diastolic volume (LVEDV),end-systolic volume (LVESV) and ejection fraction (LVEF).All above parameters were measured in patients with B-WPW before (B-WPW-B group) and after (B-WPW-A group) radiofrequency catheter ablation and in control group.The QRS width of lead Ⅱ was recorded,and the relationships between all above parameters with the RDA-B or QRS width were analyzed.Results Compared with the contrd group,in patients with B-WPW,the peak value of LV apex rotation (RotA),LV base rotation (RotB) and LV twist (TwistLV) were lower(LV base was more obvious than LV apex)(P ＜0.05),the time to RotB (TTPB) was shorter (P =0.004),RDAB was longer(P =0.002),the left ventricular enlarged and the QRS prolonged (P =0.000).After radiofrequency catheter ablation,the left ventricular torsion parameters in patients with B-WPW recovered significantly(P ＜0.05),but still lower than those in the control group(P ＜0.05).Conclusions The left ventricular motion pattern of patients with B-WPW alters,including the changes of peak value and time to peak value in LV apex rotation,LV base rotation and LV twist,as well as LV myocardium dyssynchrony.The motion pattern of LV in patients with B-WPW is improved in acute stage after radiofrequency catheter ablation but not yet recover totally.

Objective To investigate the expressions of erythropoietin(EPO)and its receptor(EPO-R)in the spinal cord after acute traumatic injury in adult rats.Methods Sixty-nine Wistar rats were randomly divided into three groups:normal control group(n=5),spinal cord injury group(n=32),and sham operation group(n= 32).The injury group and sham operation group were further randomly divided into eight subgroups respectively (n=4)(1h,6h,12h,24h,3d,7d,14d,28 dafter operation).The expressions of EPO and EPO-R at different time points were detected by RT-PCR,Western blot and immunohistochemical staining.Results EPO was nut detected at any time point in the normal control grnup,spinal cord injury group or sham operation group.The EPO-R expression was not found in the normal control group or sham operation group.RT-PCR and Western blot analyses revealed EPO-R mRNA and protein expressions in the injury group as early as 6 h after injury.The EPO-R mRNA and protein expressions sharply increased at 12 h,peaked at 24 h to 7 d,and gradually declined after 7 d. They were still higher than those in the control rats 28 d after injury.The EPO-R immunoreactivity was chiefly found in neurons,oligodendrocytes,vascular endothelial and ependymal cells.Conclusion The EPO-R expression can be up-regulated obviously in the injured spinal cord,which provides a molecular basis for the nerooprotection of exogenous EPO.

Objective: To study the relationship between human herpes vi rus 6 (HHV-6) infection and oral squamors cell carcinoma. Methods: The serum anti-HHV-6 antibody titers from 16 cases of oral squamors cell carcinoma (OSCC) and 16 control subjects were detected by indirect immunofluores cence assay. HHV-6 DNA in peripheral blood mononuclear cells was amplified by P CR and the specificity was confirmed by Southern-blot hybridization with an int ernal probe oligonuclotide. An immunohistochemical staining was used to detect H HV-6 antigen in OSCC tissues. Results: Positive expression of s erum HHV-6 IgG antibody was found in all the cases of OSCC and in 12 of the 16 controls. Geometric mean titer of OSCC group and control group was 1∶118 and 1 ∶64 respectively (P

Objective To observed the immigration and proliferation of Schwann cells in acellular xe- no-nerve graft in rats.Methods The sciatic nerves on the right side of the rats were exposc.d and 0.8cm long segments of the nerves were removed from the mid-thigh level and replaced by 1.0cm long rabbit nerves made acellular through chemical extraction.After 4 months,the immigration and proliferation of Schwann cells in the graft were revealed by HE staining,S-100 immunohistochemieal staining and transmission electromicro- scope.Results In the rats repaired by acellular nerves,regenerated axons upgrow into the graft,and a- round regenerated axons there were abundant cells aligned,the cytoplasm of which were S-100 immunoreac- tive.Electromicroscope observing showed that regenerated axons were surrounded by myelin formed by the mi- grated cells reoccupied the acellular segments.Conclusion The host Schwann cells can immigrate into rab- bit nerve grafts made acellular through chemical extraction and form myelin enwrapping regenerated axons in rats.

ObjectiveTo explore the safety and efficacy of endoscopic dilatation combined with submucosal injection of triamcinolone acetonide in treatment of benign esophageal stricture.MethodsThe patients of benign esophageal stricture proved by biopsy were randomly divided into three groups.Group A were treated by expansion only,group B were injected with triamcinolone acetonide submucosal combined with expansion,and we treated group C by another injection a week later on the basis of treatment in group B.A 12 months' follow-up was conducted,the dysphagia score,the cure rate.time to sustained symptom relief,re-expansion time interval and adverse reactions were recorded.ResultsSome patients experienced chest pain and regurgitation after the procedure and all improved by corresponding managements.No complications including massive bleeding,infection,perforation or local tissue atrophy were observed.The dysphagia scores in 3 groups after the procedure were all improved ( P ＜ 0.05 ),and no significant difference was noticed between 3 groups (P ＞ 0.05 ).At the end of the follow-up,the duration of dysphagia remission and the interval between 2 consecutive dilatation in Group A were 14.4 ± 3.2 weeks and 18.2 ± 3.7 weeks,respectively,which were significant shorter than those in Group B ( 19.3 ±3.9 weeks and 24.6 ±4.2 weeks,respectively) and those in Group C (20.2 ±4.2 weeks and 26.1 ±4.5 weeks,respectively),while there was no difference between Groups B and C.The cure rate in Group C (43.5％,10/23) was significantly higher than that of Group A (29.2％,7/24) or Group B (27.3％,6/22),while there was no difference between Groups A and B.ConclusionEndoscopic dilatation combined with submucosal injection of triamcinolone acetonide is safe and may improve the symptoms of dysphagia and delay the re-stenosis for patients with benign esophageal stricture,meanwhile,multi-frequency treatment may improve the cure rate.