Objective To evaluate the effect of low-molecular weight heparin (LMWH) on biological behavior of a human cutaneous squamous cell carcinoma cell line A431.Methods To optimize the concentration of LMWH,A431 cells were treated with different concentrations (12.5,25,50,100 and 200 IU/ml) of LMWH for 24,48 and 72 hours followed by CCK-8 assay for the detection of cell viability.Then,A431 cells were cultured with or without the presence of LMWH at 200 IU/ml for 24,48 and 72 hours.Subsequently,flow cytometry was performed to assess cell cycle,real time quantitative PCR (RT-qPCR) and Western blot to quantify the expression of vascular endothelial growth factor (VEGF) mRNA and protein respectively,double-antibody sandwich enzyme linked immunosorbent assay (ELISA) to determine the expression level of VEGF protein in the supernatant of A431 cells,wound-healing assay,Transwell assay,and adhesion assay to observe the migration and adhesivity of A431 cells.Analysis of variance and t test were carried out for statistical analysis.Results The optimal concentration of LMWH was determined as 200 IU/ml according to the CCK-8 assay,and used in the following experiment.The LMWH of 200 IU/ml resulted in a decrease in cell viability,cell cycle arrest,an increase in cell percentage in G1 phase,and a reduction in cell percentage in S phase.The proliferation index was 23.41 ± 5.51 and 11.76 ± 5.13 respectively in A431 cells at 48 and 72 hours after treatment with LMWH of 200 IU/ml,significantly lower than that in untreated A431 cells (48.62 ± 4.50,t =6.14,P ＜ 0.05; 46.86 ± 3.51,t =9.78,P ＜ 0.05).A significant decrease was observed in LMWH-treated A431 cells at 48 and 72 hours compared with the untreated A431 cells in the expression level of VEGF mRNA (10.16 ±0.07 vs.18.77 ± 0.11,4.11 ± 0.01 vs.17.39 ±0.05,t=114.38,451.10,both P＜ 0.05),VEGF protein (0.16 ± 0.01 vs.0.20 ± 0.01,0.12 ± 0.01 vs.0.21 ± 0.01,t =4.90,11.02,both P ＜ 0.05),and in the supernatant level of VEGF protein ((67.17 ± 3.34) ng/L vs. ( 122.63 ± 23.17) ng/L, (28.14 ± 3.14) ng/L vs.(86.76 ± 1.18) ng/L,t =4.10,30.27,both P＜ 0.05).The percentage of adherent cells was 29.7％ ± 1.92％ and 17.5％± 0.79％ in LMWH-treated A431 cells at 48 and 72 hours,respectively,significantly lower than that in untreated A431 cells (36.9％ ± 0.35％,34.6％ ± 0.96％,respectively,both P＜ 0.05).The migration of A431 cells was also obviously inhibited by the treatment with LMWH for 24,48 and 72 hours.Conclusion LMWH may suppress the proliferation,migration and adhesion of A431 cells via downregulating cellular viability and VEGF expression.

Objective To observe the effect of short hairpin RNA (shRNA)-mediated vascular endothelial growth factor (VEGF) gene silencing on the growth of human skin squamous cell carcinoma(SCC) xenografts in nude mice.Methods Two eukaryotic expression plasmids targeting VEGF gene,including psilencer-VEGF1-shRNA (VEGF-s1) and psilencer-VEGF2-shRNA (VEGF-s2),as well as one negative control plasmid containing random target sequence (psilencer-Target-off-shRNA,T-off),were chemically synthesized,and transfected into a human skin SCC cell line A431 to develop stably transfected cell lines.Real time quantitative PCR (RT-qPCR) and double-antibody sandwich enzyme-linked immunosorbent assay (ELISA) were carried out to measure the expression of VEGF mRNA and protein respectively in A431 cells.Twelve nude mice were divided into 4 goups to be subcutaneously inoculated in the axillary region with untransfected A431 cells as well as A431 cells transfected with VEGF-s1,VEGF-s2 and T-off,respectively.The tumor growth was observed in nude mice every 5 days.Twenty days after the inoculation,the mice were sacrificed,and transplanted tumors were obtained from the mice and subjected to an immunohistochemical study for the measurement of VEGF,proliferating cell nuclear antigen (PCNA) and CD34 expression.Data were statistically analyzed by using the Stata 7.0 software,and t test was conducted to compare the differences between groups.Results The mRNA and protein expression levels of VEGF were significantly lower in A431 cells transfected with VEGF-s1 and VEGF-s2 than in untransfected A431 cells (27.85 ± 3.95 and 24.69 ± 2.83 vs.54.06 ± 6.38,t =6.05,7.29,both P＜ 0.01; 32.67 ± 2.52 and 29.27 ± 1.10 vs.52.85 ± 2.23,t =8.04 and 11.53,both P＜0.01 ).Twenty davs after the inoculation,the volume and weight of xenografted tumors in mice inoculated with VEGF-sl- and VEGF-s2-transfected A431 cells were significantly lower than those in mice with untransfected A431 cells ( ( 192.50 ± 10.90) mm3 and (203.67 ± 3.21 )mm3 vs.(272.00 ± 21.07) mm3,t =5.80 and 5.55,both P＜ 0.01; (0.05 ± 0.03) g and (0.13 ± 0.04) g vs.(0.25 ± 0.02) g,t =9.60 and 4.64,both P＜ 0.01 ).Decreased expression rate of VEGF,PCNA and number of CD34-positive vessels were observed in the xenografted tumor tissue from mice inoculated with VEGF-sl- and VEGF-s2-transfected A431 cells compared with that from mice with untransfected A431 cells (52.00％ ± 2.00％ and 56.67％ ± 3.06％ vs.70.00％ ± 2.00％,both P ＜ 0.01;37.01％ ± 2.41％ and 33.94％ ± 3.25％ vs.72.11％ ± 3.02％,both P＜ 0.01; 2.05 ± 0.07 and 1.72 ± 0.10 vs.4.01± 1.27,both P ＜ 0.01).No significant differences were observed in the above parameters between cells transfected with VEGF-s1- and VEGF-s2-transfected A431 cells,between untransfected and T-off-transfected A431 cells,between tumor xenografts derived from VEGF-sl- and VEGF-s2-transfected A431 cells,or between tumor xenografts derived from untransfected and T-off-transfected A431 cells (all P ＞ 0.05).Conclusions The shRNA targeting VEGF gene can significantly inhibit the expression of VEGF in A431 cells and A431-derived tumor xenografts in nude mice,in turn suppress the growth and attenuate the malignant phenotype of tumor.

Objective To evaluate the effect of try psin on the proliferation,migration and adhesion of a skin squamous cell carcinoma cell line A431.Methods Cultured A431 cells were divided into several experimental groups treated with trypsin at concentrations of 0.1,1,10 and 100 nmol/L for 24,48 and 72 hours respectively,and a control group treated with DMEM complete medium only.Cell counting kit-8 (CCK8) assay was conducted to evaluate cellular proliferative activity to select the optimal concentration of trypsin.Then,some A431 cells treated with trypsin at the selected concentration for 24,48 and 72 hours respectively (or 48 hours only) served as the experimental groups (or group),and other A431 cells treated with DMEM complete medium served as the control group.Flow cytometry was performed to assess cell cycle distribution and proliferation index,fibronectin-based adhesion assay to estimate cell adhesive capacity,and wound healing assay and Transwell assay were conducted to evaluate the migratory capacity of cells in two-and three-dimensional space.Statistical analysis was carried out by using analysis of variance,paired samples t test and chi-square test.Results The proliferative activity of A431 cells increased along with the increase of trypsin concentrations,with the strongest increasing effect observed at 100 nmol/L.After treatment with 100 nmol/L trypsin,the experimental group showed a decrease in the percentage of G1-phase cells,but an increase in the percentage of S-phase cells,proliferation index,migratory and adhesive capacity compared with the control group (all P ＜ 0.05).Conclusion Trypsin can promote the proliferation,migration and adhesion of A431 cells.

AIM:To study the reversal effects of multidrug resistance by transfecting tumor necrosis factor ?(TNF-?) cDNA and multidrug resistant 1(MDR1) gene antisense RNA into multidrug resistant breast cancer cell line MCF-7/ADR.METHODS:The recombinant vector of enhanced green fluorescent protein(EGFP) with MDR1 antisense RNA and recombinant vector of red fluorescent protein(DsRed2) with TNF-? cDNA were constructed by RT-PCR and DNA recombinant techniques.The recombinant vectors were transfected into multidrug resistant breast cancer cell line MCF-7/ADR.The cell growth curves,cell apoptosis rates,MDR1 gene expression at mRNA and P-gp levels,and the sensitivity to ADR were determined before and after the transfection.RESULTS:After the transfection,cells showed lower growth rate,higher apoptosis rate,lower MDR1 expression at mRNA and P-gp levels,and the sensitivity to ADR increased significantly.CONCLUSION:Transfection of TNF-? cDNA and MDR1 antisense RNA into multidrug resistant breast cancer cells may have good effects on reversal of multidrug resistance.

Objective To understand and analyse the epidemic status of human intestinal nematode infection in Jiangsu Province, so as to provide basis for making control measures. Methods The typical thirty-nine spots in thirteen counties among the sampling spots of National Investigation on Distribution of Human Parasites in 1990 were selected and investigated according to the Methods of National Investigation Scheme on Human Principal Parasites in 2004. Results The total prevalence was 3.88%, which decreased by 46.92% compared with the investigation in 2002 (7.31%). The infection rates of hookworm, Ascaris and Trichuris were 1.14%, 1.06% and 1.73%, respectively, and the proportion of light infection was 91.75%. The rate of multiple infections was 9.40%. The proportion of hookworm infection was 78.06% in Southern Jiangsu and the proportion of Ascaris or Trichuris was 89.03% in Northern Jiangsu. The infection rate of Enterobius was 3.72% among children aged less than 12 years. Conclusions The prevalence of intestinal nematodes has decreased to lower level in Jiangsu Province. The difference of prevalence in different regions has a relationship with the disease control and social-economic, culture and health levels. The principal control work should be still put in the northern part of Jiangsu Province. The preschool children and the middle and old age peasants are high-risk population. The different control measures should be taken in accordance with the situation of different regions in the future.

Objective To investigate the clinical characteristics,treatment effect,long-term follow up results,guanosine triphosphate (GTP) cyrclohydrolase Ⅰ (GCH Ⅰ)gene and tyrosine hydroxylase(TH) gene mutations in patients with dopa-responsive dystonia (DRD).Methods The clinical features of 3 families with 4 affected members were analyzed and all of 4 patients were screened for mutations of the GCH Ⅰ gene and TH gene with DNA sequences.Results Four patients were females,average age at onset was (15.3 ± 5.6) years (range:from 9 to 20 years).The initial symptoms were a gait disorder,stiffness or tremor of the lower limbs in all patients presented with diurnal fluctuation.As the increase of disease duration,bilateral hand tremor was found in three patients,systemic torsion was found in one patient and torticollis was found in one patient.All patients' symptoms were in complete remission after administration of low dose of levodopa.Four patients were followed up for 0.5 to 10.0 years,and all were still responsive to the levodopa treatment and effective dosage was decreased as the increase of the disease duration.No longterm side effects of levodopa had occurred after long-term treatment.One patient was found to have c.607G ＞A(p,Gly203Arg) heterogenetic mutation in GCH I gene.Molecular analysis revealed a compound heterozygous mutation in the TH gene (p.Y447Ter and p.V468M) in one patient.No point mutations in both genes were found in other patients.Conclusions DRD patients have dramatic and sustained response to levodopa and no long-term side effects of levodopa after long-term treatment.The detection of GCH Ⅰ and TH gene mutations is helpful in early diagnosis but the negative results could not exclude the diagnosis of DRD.

Objective To investigate and analyze the changes of Ascaris lumbricoides infection in rural residents of Jiangsu Province during 13 years and its influencing factors in order to provide the basis of making practical policies for ascariasis control in future. Methods The data were analyzed about the rates of Ascaris infection and mass chemotherapy, per capita income, and the rates of the use of running water and hygienic toilets in the southern part, the middle part and the northern part of Jiangsu Province from 1990 to 2002, and the main influencing factors for Ascaris infection were explored. Results The prevalence rate of Ascaris infection decreased continuously during 13 years, from 39.51% to 2.14%, and the decrease rate was 94.58%. In 2002, the infection rate was the lowest, only 0.41%, decreased by 98.92% in the middle part of Jiangsu Province, and the infection rate was the highest, 5.09%, decreased by 89.97% in the northern part of Jiangsu Province. The accumulated rates of mass chemotherapy were 159.00% in middle part of Jiangsu Province,103.00% in the southern part of Jiangsu Province and 105.00% in the northern part of Jiangsu Prvince.The per capita income, the use of running water and hygienic latrines increased gradually from the northern part to the southern part and there were significant differences in the 3 survey regions. Conclusion The Ascaris infection rate is influenced by mass chemotherapy, economics and health conditions in rural residents, especially the mass chemotherapy.

Objective To understand the status and characteristics of principal human parasitic infections in rural areas of Jiangsu Province in order to provide basis for decision-making of practical control measures. Methods The survey data of principal human parasites in 58 sample sites of 19 counties (cities or areas) in Jiangsu Province were analysed on family clustering by G test, according to the methods of National Investigation Scheme on Principal Human Parasites. Results The infection of Ascaris lumbricoides, hookworm, Trichuris trichinra and Clonorchis sinensis in the province had obvious family clustering, while those in each county (city or district) appeared different states in some-points with the changing of parasitic infection rates and infection degrees. Conclusions The infection rates and infection degrees of principal human parasites decrease obviously in Jiangsu Province. The family clustering is disappearing with the dropping of them. Chemotherapy in family and health education should be strengthened to consolidate the control results in future.

Objective To understand the present status of human parasitic infections and their characteristics in rural areas of the southern part of Jiangsu Province, to provide basis of making practical control measures.Methods Four thousand and eighty-two people were examined with stool tests and those people were distributed in 8 slected spots in the southern part of Jiangsu Province,according to the methods of national investigation scheme on human principal parasites. Results The avarage infection rate of parasites was 6.71%. The male and female infection rates of parasites were 4.77% and 8.42%,respectively. There were significant differences (P

Objective To enhance clinicians' intention to the importance of early diagnosis,early therapy and follow-up of type Ⅱ citrullinemia.Methods The clinical data of one adult-onset type Ⅱ citrullinemia pedigree were collected. The gene mutation type of SLC25A13 of proband and her daughter were determined by PCR and direct gene sequencing.Results The patient was a 27 years-old female,who complained of repeated dizziness, vomiting for more than 2 years and recurrent attacks of altered consciousness for about one and a half year.An abdominal ultrasonogram,liver magnetic resonance imaging and liver histology obtained by needle biopsy all determined the liver pathological changes of liver cirrhosis.Electroencephalogram showed sharp waves. The plasma amino acid showed a marked elevation of blood citrulline.Laboratory findings revealed a highly increased concentration of plasma ammonia during every episode. Mutation analysis of the SLC25A13 gene identified a homozygote of 851del4 in the patient,and heterozygote of 851del4 in her daughter. Conclusions For adults,unexplained dizziness,vomiting,but liver function still in the compensation,especially accompanied by neuropsychologic symptoms are highly suggestive of adult-onset type Ⅱ citrullinemia.SLC25A13 gene analysis contributes to the diagnosis of this disease,avoids invasive investigations and early confirmation of this disease means long-term dietary advice,genetic counseling,medical surveillance and early preparation for liver transplantation if is necessary.