Objective To assess the mutagenicity of polycyclic aromatic hydrocarbons(PAHs) extracted from the atmospheric particulates collected from different aerodynamic sizes,seasonal variation and the sampled sites,and to detect the effect of these factors on the mutagenic activity of PAHs.Methods PAHs were extracted from the atmospheric particulates(PM10 and PM2.5) collected from two different sites,business area and industrial area(summer and winter respectively).The mutagenicity of these PAHs samples was evaluated by the Salmonella mutagenicity assay(Ames assay),using Salmonella typhimurium strains TA98 and TA100 with and without metabolic activation(S9).Each sample was assayed in three doses(125,250 and 500?g per plate).Results All samples induced the number of revertants to be higher measured with TA98 with and without S9 mix.The level of specific mutagenic activity measured with strain TA98 was higher than TA100.Metabolic activation with the S9 fraction increased the mutagenicity of the industrial area samples studied for the strain TA98.All groups showed a good dose-response relationship of mutagenicity(P

Nisin is a cationic antimicrobial peptide produced by some lactic acid bacteria. However, expression of nisin resistance protein (NSR) could confer nisin resistance on some non-nisin-producing Lactococcus lactis. To deeply elucidate molecular mechanism underlying NSR-mediated nisin resistance, an NSR mutant with N-terminal 38 amino acid residues deleted (NSR?38) was overexpressed in Escherichia coli by fusion with GST. Purified NSR?38 was obtained through glutathione (GSH) affinity chromatography followed by cleavage of GST tag. Putative proteolytic activity of NSR?38 was determined in vitro against nisin. Antimicrobial activity analysis revealed that nisin lost its bactericidal activity after incubation with NSR?38. Further reversed-phase high performance liquid chromatography (RP-HPLC) analysis indicated that NSR?38 displayed proteolytic activity against nisin, thus inactivating the antimicrobial peptide. The current study paves the way for in-depth functional studies on NSR.

Objective To prepare anti-activin receptor-interacting protein 1 (ARIP1) polyclonal antibody.Methods The GST-ARIP1 fusion protein was expressed in E.coli BL21.A polyclonal antibody against ARIP1 was obtained by immunizing a rabbit with the purified GST-ARIP1 and the localization of mature ARIP1 protein in mouse brain tissues was detected by immunohistochemistry using the prepared anti-ARIP1 antibody.Results Anti-ARIP1 polyclonal antibody could bind specifically with recombinant ARIP1,but not recombinant ARIP2.Immunohistochemical staining showed that ARIP1 mainly expressed in hypothalamus and hippocampus using the prepared anti-ARIP1 antibody.Conclusion The polyclonal antibody against ARIP1 has been successfully prepared and can be used to do immunohistochemical analysis for ARIP1 protein expression.

BACKGROUND: Cephalocervical cancer is closely related with genetic factors, but do the first-degree relatives have a higher risk for cancers? Slenderstyle acanthopanax root-bark has an anti-mutation chromosome stabilizer, can it enhance the anticaner ability of the first-degree relatives? OBJECTIVE: To study the genetic factor of cephalocervical cancer and antimutagenic effect of slenderstyle acanthopanax root-bark.DESIGN:A controlled experiment with human peripheral blood as the sample.SETTING: The Department of Medical Genetics of the Basic Medical Science School, and the Department of Otolaryngology of the First Hospital of Jilin University; The University of Warwick, UK.PARTICIPANTS: The subjects were taken during the period of October 2001 to March 2002. The patients with cephalocervical tumor and their first-degree relatives were all from the Department of Otolaryngology,FirstHospital of Jilin University, and healthy group were well-being blood devoting volunteers from Changchun City Central Blood Bank. There were group( n = 50) included 25 males and 25 females who were healthy blood patients group( n =30) were composed of 22 males and 8 females who did first-degree relative group(n=30) consisted of 19 males and 11 females. They were the first-degree relatives of patients with carcinoma of larynx and carcinoma of nasopharynx. Except for the family history of cancer,they themselves were all healthy. Informed consents were obtained from all of them.METHODS: The peripheral blood was collected as the sample and the lymphocyte culturing was performed. The culture cycle was 72 hours and bleomycin(BLM) (15 mL) was added into it at the 67~ hour, also the slenderstyle acanthopanax root-bark(SARB) (800 mg/L) was added into the antimutagenesis experiment. The cells were collected after culturing for another 72 hours. The conventional method was used for slide preparation. The slides were stained with Giemsa solution without banding. Choosing the proper objective and observing the numbers of chromatid breaks. The numbers of chromatid breaks were converted into the numbers of chromatid breaks per cell (b/c value). Namely, b/c value equals to the quotient, the number of chromatid break divided by the number of the cell observed in the slide.MAIN OUTCOME MEASURES: The number of chromatid breaks per cell (b/c value).RESULTS: All the 110 cases in the 3 groups entered the stage of result It was lower in the control group than that in the patients group and first-degree relatives group(0.16 ± 0.06, 0.48 ± 0. 14, 0.42 ± 0. 12, P ＜0.01). There was no significant difference in b/c value between the paparison between b/c value induced by combined SARB with BLM and only BLM was performed: The b/c value of former is significantly lower than the latter (0.48±0.14,0.15 ±0.08,0.42±0.12, 0.17±0.11,P ＜ 0.01).CONCLUSION: The first-degree relatives of the patients with cephalocervical cancers should be classified as tumor high-risk group. SARB as a chromatid stabilizer has an obvious inhibitory effect on b/c value of the patients induced by BLM and that of the first-degree relatives.

Objective To observe the expression of neural nicotinic acetylcholine receptor subunit α3 (α3nAChR) and extracellular regulated protein kinases (ERK1/2),c-Jun N-terminal kinase (JNK),p38 kinases of mitogen-activated protein kinase (MAPK) pathway in human neuroblastoma cell line SH-SY5Y overexposed to fluoride,and try to investigate the molecular mechanism of cell damage caused by overexposure of fluoride.Methods The SH-SY5Y cell with low expression of α3nAChR suppressed by silence interference RNA served as α3nAChR silence group;the normal SH-SY5Y cell served as control group,and the effect of silencing of αt3nAChR gene in SHSY5Y was detected by Western blotting and real-time PCR;SH-SY5Y cell was treated with different concentrations of fluoride (0.000,0.005,0.050,0.500,1.000,2.500,5.000 mmol/L),the safe concentration of fluoride in SHSY5Y cell was detected by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) assay;the SH-SY5Y cell of control group and α3nAChR silence group were treated with 4.000 mmol/L fluoride for 0,4,8,12,24,36,48 h according to the results of MTT assay;the expression of ERK1/2,JNK,p38 kinases of MAPK pathway in SH-SY5Y at protein levels was measured by Western blotting.Results The expression of α3nAChR mRNA (0.04 ± 0.03) and protein (12.0 ± 2.5) in α3nAChR silence group was decreased significantly compared with those of control group (1.00 ± 0.11,100.0 ± 11.3,t =24.58,28.80,all P ＜ 0.05).The viability of SH-SY5Y cell treated with 5.000 mmol/L fluoride (0.53 ± 0.15) was decreased significantly compared with that of SH-SY5Y cell treated with 0.000 mmol/L fluoride (1.05 ± 0.05,P ＜ 0.05).The increased expression of phospho-ERK1/2 was found in α3nAChR silence group and control group incubated with fluoride with time prolonged,and the expression of phospho-ERK1/2 increased significantly at time points 24,36 and 48 h (188.33 ± 7.33,200.00 ± 10.01,213.33 ± 11.55;125.33 ± 5.69,136.00 ± 4.52,155.33 ± 6.51) compared to 0 h in the same groups (100.00 ± 0.00,100.00 ± 0.00,all P ＜ 0.05),and the expression of phospho-ERK1/2 was higher significantly in α3nAChR silence group than those of control group (t =9.26,7.63,5.72,all P ＜ 0.05);no change of expression of total-ERK1/2 in the two groups was found with the passage of time.The gradually increased expression of phospho-JNK was found in α3nAChR silence group and control group,among which,the expression of phospho-JNK in o3nAChR silence group at time points 12,24,36 and 48 h (154.00 ± 6.25,149.00 ± 5.57,156.00 ± 6.08,141.67 ± 2.52) and in control group at 8,12,24,36,48 h (133.33 ± 10.69,173.00 ± 4.00,175.00 ± 11.79,200.67 ± 11.93,200.33 ± 18.58) was compared to those at 0 h in the same groups (100.00 ± 0.00,100.00 ± 0.00),and the difference was significant (all P ＜ 0.05);the higher expression of phospho-JNK was found in α3nAChR silence group other than control group at 8,12,24,36,48 h (t =-4.28,-5.02,-2.89,-8.33,-6.18,all P ＜ 0.05);no change of expression of total-JNK was found in the two groups (P ＞ 0.05).The increased expression of phospho-p38 was detected in control group at time points 24,36 and 48 h (120.33 ± 4.51,122.00 ± 7.55,119.67 ± 7.57) compared to 0 h in the same groups (100.00 ± 0.00,all P ＜ 0.05),and the expression of phospho-p38 was significantly higher than that in α3nAChR silence group at the same time points (93.33 ± 9.61,94.00 ± 5.01,98.33 ± 5.69,t =-4.01,-6.73,-5.59,all P ＜ 0.05);no change of expression of total-p38 was found in the two types of SH-SY5Y cells treated with fluoride (P ＞ 0.05).Conclusion When SH-SY5Y cells are exposed to fluoride;activation of ERK1/2 may be not depend on α3nAChR;α3nAChR may have protected the cell from apoptotic injury caused by activation of JNK pathway,and the activation of p38 may be depend on nAChRα3.

Objective To observe the treatment difference of using acupiont application alone, pricking Sifeng (EX-UE10) alone, and combination of the two therapies in treating infantile chronic cough. Method Ninety patients were randomized into 3 groups (acupoint application group, pricking Sifeng group, and a combining group), 30 in each group. Same points were selected for the three groups:Feishu (BL13), Pishu (BL20), Shenshu (BL23), and Sifeng (EX-UE 10). By follow-up research of the symptom scale, the therapeutic efficacies were compared. Result The total effective rate was 83.3%in the acupoint application group, 80.0%in the pricking Sifeng (EX-UE 10) group, and 93.3%in the combining group;meanwhile, the symptom scores were significantly changed after intervention in all three groups (P＜0.05). Conclusion Separate use and combining use of acupoint application and pricking Sifeng (EX-UE 10) all can improve the condition of infantile chronic cough, while the combining use can produce a significantly higher therapeutic efficacy, thus it’s a safe, effective, and easy-to-operate external treatment in traditional Chinese medicine.

Objective To explore the diagnositic value of dual-phase contrast enhancement CT combined with virtual non-enhanced images by dual-energy CT in clear cell renal cell carcinoma.Methods Sixty patients who were suspected of clear cell renal cell carcinoma underwent non-enhanced CT and contrast enhancement CT of early interface-phase between cortex -medulla and parenchymal phase on a dual-energy CT.The true non-enhanced kidney CT(TNCT) was performed in a single-energy acquisition mode,but the dual-phase contrast enhancement CT were performed in a dual-energy mode of 80 kV and 140 kV respectively.The virtual non-enhanced CT ( VNCT ) images were derived from the data of early interfacephase using liver virtual non-contrast software.The diagnosises according to VNCT combined dual-phase contrast enhancement CT and dual-phase contrast enhancement CT only were made respeetively and compared with x2 test.Between the true non-contrast CT and the virtual non-contrast CT,the image quality was compared with Wilcoxon test ; The radiation dose of volume CT dose index ( CTDlvol ) and dose length product(DLP) in a single-phase and total examination,the mean CT HU values of the tumours werecompared with t test.Results The accuracy of VNCT combined dual-phase contrast enhancement CT was higher than that of dual-phase contrast enhancement CT only [93.3％ ( 56/60 ) vs.78.3％ ( 47/60 ) ; x2 =5.6,P ＜0.05].The detective ability (score) of VNCT was near to that of TNCT and the difference was not obvious( Z =0.00,P ＞ 0.05 ). The radiation dose of volume CT dose index ( CTDIvol ) and dose length product(DLP) in a single phase and total examination of VNCT[(8.85 ± 1.28) mGy,(196.45 ±21.12) mGy·cm,(17.69±2.35) mGy,(392.90±42.25) mGy · cm] were lower than that of TNCT [( 10.20 ± 1.44 ) mGy,( 218.29 ± 29.60 ) mGy · cm,( 30.61 ± 3.27 ) mGy and ( 654.86 ± 88.81 ) mGy ·cm],t =4.21,3.58,23.63,16.12 respectively,P ＜0.05.The mean CT HU values of tumours on VNCT images was higher than that on TNCT images and the difference was significant [(39.37 ± 6.35 ) vs.(34.94 ± 7.00 )HU,t =- 14.39,P ＜ 0.05].Conclusions The diagnositic value of dual-phase contrast enhancement CT combined virtual non-enhanced CT by dual-energy CT for clear cell renal cell carcinoma was obvious,most tumours can be diagnosed correctly,and the radiate dose can be decreased obviously,the normal single-energy non-enhanced and contrast enhancement CT might be replaced in the future.

Objectives To investigate the possible role of perforin (PFN) in the pathogenesis of severe preeclampsia.Methods Thirty-two cases of severe preeclampsia were included in the study.Thirtytwo cases of normal pregnancy were selected as control group in random.The expression of PFN mRNA in the peripheral blood mononuclear cells (PBMC) was detected by reverse transcription (RT)-PCR, and its correlation with mean arterial pressure was analyzed in severe preeclamptic patients.The expression of PFN protein in the decidua was detected by immunohistochemistry.Results ( 1 ) The expression of PFN mRNA in PBMC:the PFN mRNA level in severe preeclamptic group was 1.19 ± 0.31, and that in normal pregnancy group is 0.82 ± 0.28.The PFN mRNA level in severe preeclamptic group was significantly higher than that of control group (P ＜ 0.0l ).(2)Correlation analysis:the mean blood pressure in severe preeclampsia group was (133 ±5) mm Hg( 1 mm Hg =0.133 kPa).There was significant positive correlation between level of PFN mRNA in PBMC and mean blood pressure in severe preeclamptic patients ( r = 0.701, P = 0.000).(3)Decidual PFN protein expression:PFN protein was mainly expressed in lymphocytes and the cytoplasm of decidual stromal cells.The positive ratio of PFN in the decidua of severe preeclamptic patients was 84% ( 27/32), significantly higher than that of control group (53%, 17/32, P ＜ 0.01 ).Conclusions Expression of PFN was significantly increased in severe preeclampsia, and it was of significant positive correlation with mean blood pressure.PFN may participate in the pathogenesis of severe preeclampsia.

Objective:To investigate the correlation between the disease activity of ulcerative colitis (UC) and the immunohistochemical distribution of calprotectin in colon mucosa,as well as the levels of calprotectin in fecal. Methods:Monoclonal antibody against calprotectin was used to investigate the distribution of these proteins in colon mucosa from 42 patients with ulcerative colitis and 20 healthy controls. ELISA assay was used to measure the concentrations of calprotectin in fecal. The disease activity of UC was determined by Truelove-Witts histological criteria. Results: Calprotectin was demonstrated in the majority of granulocytes and macrophages in colon mucosa of patients with active UC, while negative in patients with unactive UC and healthy controls. A strong calprotectin immunoreactivity was presented in ulcerative and erosion lesions in the colon. The concentration of calprotectin was significantly higher in patients with active UC than that with unactive UC and healthy controls (P

The teaching methods were explored to improve the quality of medical genetic teaching for foreign students according to the common problems during the teaching process. The negative effects of communication barriers in medical genetic teaching could be reduced by interactive teaching or problem-based learning in groups,in which the ability to resolve problems by themselves could be improved. In order to improve the teaching systematicness and teaching quality,the teaching contents in class should be from simple to deep,covering genetic laws,pathogenesis,diagnosis and control measure of genetic diseases. From the perspective of practical application and combining with the construction of self-de-signed teaching textbook and cases, the quality of medical genetic teaching ultimately could be further improved.