Objective To establish a high sensitive spectrophotometry for determination of trace cadmium in the water. Methods A complicated ion-association complex of Cd(Ⅱ)-potassium iodide-malachite green was formed in the phosphate acid, and the addition of gelatine could enhance the sensitivity of the reaction.The maximum absorption of the ion-association complex was at 680 nm,the effect of experimental conditions such as the reagents concentration,the temperature and the influence of foreign matters were considered.Results In the optimum condition(6.0 ml of 40% potassium iodide-aseorbic acid solution,0.5 ml of 5.0 mol/L phosphate acid solution,0.5 ml of 0.5% gelatine solution,1.5 ml of 1.0?10~(-3)mol/L malachite green solution in a 25ml volumetric flask,diluted with water and mixed well and determined immediately),the linear regression equation was △A=0.011+ 0.957 c,r=0.998 5.Beer's law was obeyed in the range of 0.02 ?g/ml to 0.80 ?g/ml for Cd(Ⅱ)and the limit detection was 0.02 ?g/ ml.The composing ratio of the complex was MG:Cd:I=2:1:4,and its apparent molar absorptivity coefficient was 1.08?10~5 L/(mol? cm).The recovery rates of Cd(Ⅱ)were 97.0%-101.5%,RSDs were 1.36%-3.58%.Conclusion This method is sensitive,simple, rapid and is applicable to the determination of the trace Cd(Ⅱ)in water.

AIM: To study if the effect of arsenic sulfide combined with IFN-α can be increased on K562 cells. METHODS: Telomerase activity was determined by PCRELISA. Flow cytometry was used to analyze the cell apoptosis. The final concentration of IFN-α and arsenic sulfide was 10 000 U/mL and 0.6 mg/L. RESULTS: The rates of apoptosis was 37.8% and 37% in K562 cells treated with IFN-α or arsenic sulfide alone for 8 days; The rates of apoptosis and inhibition of telomerase activity was 59.9% and 81.2% in K562 cells treated with IFN-α and arsenic sulfide simultaneously for 8 days, or 60.37% and 78.8% in K562 cells was treated with arsenic sulfide for 5 days after affected by IFN-α for 3 days. 71.3% telomerase activity was inhibited in K562 cells by arsenic sulfide alone for 8 days. CONCLUSION: Combination of arsenic sulfide and IFN-α can increase the apoptosis and inhibit the telomerase activity of K562 cells obviously comparing with the two drugs used alone. IFN-α maybe promote arsenic sulfide inducing apoptosis of K562 cells.

This study aimed to investigate the therapeutic effect and possible mechanism of carboxyamidotriazole (CAI) on imiquimod (IMQ)-induced psoriasis-like mice model and M5 (IL-1α, IL-17A, IL-22, TNF-α and oncostatin M)-induced keratinocytes model of psoriasis. The severity of psoriasis-like skin lesion in mice was evaluated by psoriasis area and severity index (PASI) score. The histopathological changes of skin were examined by hematoxylin-eosin staining and Baker score was calculated. The levels of pro-inflammatory cytokines in skin were measured by enzyme-linked immunosorbent assay. Transcriptome sequencing technique was used to analyze differentially expressed genes (DEGs) and real-time quantitative PCR (qPCR) was used to detect mRNA expressions. The animal experiments conducted in this study were approved by the Institutional Animal Care Use & Welfare Committee of Institute of Basic Medical Sciences, Chinese Academy of Medical Science (grant No. ACUC-A02-2022-115). The results showed that CAI significantly improved the severity of psoriasis-like lesion, reduced PASI score, attenuated pathological changes, decreased Baker score and inhibited the levels of IL-1β, IL-6, IL-17A, IL-23 and TNF-α in skin of IMQ-induced mice. Transcriptome sequencing analysis revealed that regulating keratinocytes and their mediated keratinization might be involved in the mechanism of CAI. Further qPCR study validated that CAI down-regulated the mRNA expression of DEG S100a7. Moreover, the keratinocyte model of psoriasis was established by stimulating HaCaT cells by M5. It was shown that CAI decreased the mRNA expression levels of S100a7, Il1β, Il6, Il17, Il23 and Ccl20, which were up-regulated by M5 stimulation. In conclusion, CAI might have a good therapeutic efficacy on psoriasis, and its mechanism was related to regulate the function of keratinocytes and downregulate cytokines and S100a7.

Objective To analyze the imaging features and follow-up changes of high-resolution CT(HRCT) in Goodpasture syndrome.Methods HRCT imaging features and follow-up findings of 15 cases Goodpasture syndrome confirmed by clinical were analyzed retrospectrively.The imaging features included extent,forms and follow-up changes.Results The lung lesion of Goodpasture syndrome involved two lobes(n=1), three lobes(n=2), four lobes(n=5) and five lobes (n=7).Upper lobe of the right lung was the most common involved region.Centered on the hilum of lung consolidations confused ground glass opacity (GGO) were showed in 7 cases, GGO distribution of pulmonary leaflets in 5 cases.On follow-up observation, lobar or segmental consolidation could change into GGO,GGO could disappear in short times.Conclusion Multiple lobar or segmental consolidations confused GGO without the lung bottom and periphery involvement is the imaging characteristics of Goodpasture syndrome patients with anemia and hemoptysis.HRCT is a helpful method for the diagnosis and following up of Goodpasture syndrome.

Objective To explore the roles of Notch2,Notch4 in hyperoxia induced lung injury in premature rats.Methods At the postnatal 1 day Sprague-Dawley premature rats were randomly assigned to about 85% hyperoxia group and air group.At the 1,7,14,21 days after exposed,8 rats of each group were used to evaluate expressions of Notch2,Notch4 in lungs by immunohistochemistry and the level of Nothch2,Notch4 mRNA by reverse transcription polymerase chain reaction(RT-PCR).Results Expressions of Notch2,Notch4 had their rules in rats′ different stages of development;85% oxygen exposed would change their tracks.Conclusion Prolonged 85% oxygen exposure result in abnormal expressions of Notch2 and Notch4 ,which is likely to lead to the pathogenesis of hyperoxic lung injure in premature rats.

Objective:To investigate the effect of NS-398,a selective cyclooxygenase-2(COX-2) inhibitor,on the proliferation and invasion of human colon carcinoma cells in vitro,so as to determine the possibility of COX-2 as a new target for treatment of colon carcinoma.Methods: The expression of COX-2 in colorectal cancer cells(CW-2,COLO-320) was detected by RT-PCR and Western blotting.COLO-320 cell proliferation was measured by MTT after treatment with NS-398.Cell invasion ability was measured using migration and invasion chamber systems.Western blotting assay was used to examine the influence of NS-398 on MMP-2 expression.Results: Our results showed that CW-2,COLO-320 cells expressed COX-2 mRNA and protein.NS-398 inhibited the proliferation of COLO-320 cells in a time-and concentration-dependent manner.Invasion test showed that NS-398 inhibited the migration and invasion of COLO-320 cells.Western blotting revealed that NS-398 inhibited the expression of MMP-2 in COLO-320 cells.Conclusion: The selective COX-2 inhibitor NS-398 can inhibit COLO-320 cell proliferation and invasion,indicating COX-2 may serve as a new target for colon carcinoma treatment.

Objective To study the protective effect of compound nitroglycerin gel on rats with skin ulcer wound and its action mechanism. Methods Skin ulcer modle of 54 rats was established.Then the rats were randomly divided into three groups (n=18 each), including model control group, Jin wan hong group, and compound nitroglycerin gel group. Wound healing process and healing time were recorded.At the day 7 and 14 after the model was established, the number of fibroblasts and new blood capillaries of granulation tissue from center of the wound were measured,and RT-PCR was used to detect mRNA expression levels of VEGF, Ang1 andHIF-1α. Results As compared with model control group [(24.17±5.91) days], healing time of skin in the compound nitroglycerin gel group was significantly shorter [(14.67±3.76) days, P<0.01].The numbers of fibroblasts (61.20±7.56) and new blood capillaries (9.35±1.43) were increased, and mRNA expression levels of VEGF (1.692±0.196), HIF-1α (1.527±0.174) and Ang1 (1.548±0.203) were remarkably up-regulated on 7th day (P<0.05 or P<0.01).While on 14th day, the numbers of fibroblasts (28.00±5.96) and new blood capillaries (4.20±1.30) were decreased and the mRNA expression levels of VEGF (1.156±0.123), HIF-1α(1.021±0.105) and Ang1 (1.034±0.134) were significantly down-regulated (P<0.05 or P<0.01) . Conclusion Compound nitroglycerin gel can treat skin ulcer wound via regulating the numbers of fibroblasts, new blood capillaries and VEGF/Ang1/HIF-1α signal transduction pathway.

Objective Based on dual channel melting curve analysis-based assay,we developed a method to rapidly detect the drug-resistant mutations in Mycobacterium tuberculosis through real-time PCR.Methods According to the common first-line drug-resistant mutations of Mycobacterium tuberculosis,we designed six dual-labeled fluorescence probes to rapidly detect the drug-resistant mutations through realtime PCR melting curve after amplifications of drug-resistant related gene region of DNA.The targets include rpoB 81 bp core region,katG315,inhA promoter,ahpC promoter and embB306.To validate the sensitivity and specificity of our method,we performed real-time PCR assays to detect drug-resistant mutations in 76 clinical MDR-TB samples,which were collected by Shanghai CDC in 2008.Results In the validation,this method successfully detected drug-resistant mutations in all 76 clinical MDR-TB samples.The △Tm of mutations were from 1.8 to 14.4 ℃.Comparing with the sequencing data,all mutations covered by the six probes were detected with 100％ sensitivity and 100％ specificity (rpoB,80/80; inhA,7/7 ; katG315,59/ 59;ahpC,8/8;embB306,27/27).This method can successfully detect drug-resistant mutations from 100 copies/μl DNA samples.Conclusions A widely applicable real-time PCR assay to detect first line drug-resistant mutations of Mycobacterium tuberculosis has benn developed.This method has proven to have the advantages of high sensitivity,specificity and low risk of contamination.It can be used in rapid diagnosis of clinical drug-resistant tuberculosis and the evaluation of laboratory drug sensitivity test.

Objective To study the relationship between hepatitis B virus(HBV)pre-S gene mutations and progression of liver disease.Methods The entire pre-S1,pre-S2 genes were amplified hy nested polymerase chain reaction(PCR)and the products were digested by NlaⅢ.The method for detecting pre-S2 start codon mutation was established based on the digested restriction fragment length polymorphism(RFLP).Pre-S gene deletion was revealed by electrophoresis on polyacrylamide gel(PAGE).Pre-C A1896 and basic core promoter T1762/A1764 mutations were identified by direct sequencing of PCR products.The 138 sera from patients with HBV-related disease,including asymp- tomatic carriers(ASC),chronic hepatitis(CH),liver cirrhosis(LC),hepatocarcinoma(HCC),were tested by these methods.Results The detection rate of pre-S deletion mutation was higher in patients with HCC(56.3%)and LC(42.9%)than those with CH(11.8%)and ASC(8.1%,P

Objective:To summarize the clinical characteristics of 7 sporadic cases in children of influenza A (H1N1)broken out in Tianjin,and to provide clinical experience and prognosis factors for the diagnosis and prevention of this disease.Methods:The clinical data and protective measures were retrospectively analyzed in 7 children with H1N1 confirmed by Tianjin Haihe Hospital from June 9,2009 to September 21,2009,and the related literatures were reviewed.Results:There were six imported cases of H1N1 and one second-generation case.Fever and cough were the main symptom in children.There were 5 children with hyperpyrexia.Three were with expectoration.Other symptoms included anergy,dizziness,headache,nasal discharge,sneeze and pharyngalgia.Two of these children were with leukocytosis decrease,two were with infection of leukocytosis,and others were normal.Five of these children were with normal chest X-ray,one with texture disorder, and one with bilateral multiple infiltrating image.The positive influenza A virus result was detected by real-time PCR and sequencing comparison in the throat swab samples taken within 2 days from the seven children,and became negative after 5-9 days in the course of this disease.Six patients were accepted osehamivir treatment for 5 days.One was treated only with anti-virus mixture.The average length of hospital stay was 7.9 days.When the children were discharged from hospital,all the symptoms were disappeared.All the patients'families,doctors and nurses were not infected in non-directly exposed to the disease.Conclusion:The seven child patients showed mainly symptoms of fever and cough.The average course was 9.1 days,and they were all cured.Therefore,influenza A(H1N1)is preventable and curable.