Background and purpose:Zhongshan City is one of the areas with the highest NPC incidence worldwide and nationwide. Although its incidence rate had been analyzed thoroughly, but its mortality rate was not studied further until now. This study was to explore NPC mortality status in Zhongshan City from 1970 to 2010, and to provide scientiifc information for its control and prevention.Methods:NPC death data in Zhongshan City from 1970 to 2010 came from Zhongshan Cancer Registry Ofifce. Such indices as its death number, crude rate, age standardized rate (ASR) and truncated rate etc were calculated and analyzed. Results:There were 5 267 NPC death cases in Zhongshan City from 1970 to 2010, its crude world ASR and truncated rates were 11.03/105, 12.34/105 and 29.31/105 respectively. Its world ASRs increased before 1999 but no statistical signiifcance (P=0.64) and decreased thereafter with obvious statistical signiifcance (P=0.001). But overall, there were a decreasing trend for its ASRs (P=0.001) from 1970 to 2010 in Zhongshan City. Moreover, NPC mortality rate in male was remarkably higher than in female, the death peak age was 55-59 age group, and the different age groups were with different trends fro 1970 to 2010. Conclusion:Although with declining trend from 1970 to 2010, NPC mortality rate in Zhongshan City was at high level worldwide. It suggested that NPC control and prevention should be enhanced.

Objective: To investigate the impact and its possible mechanism of hydrogen sulfide (H2S) on myocardial collagen remodeling in experimental rats with diabetic mellitus (DM).
Methods: Rat’s DM model was established by intraperitoneal injection of STZ at 40 mg/kg. A total of 40 SD rats were randomly divided into 4 groups:Control group, DM group, DM+NaHS group, in which NaHS worked as exogenous donor of H2S and NaHS control group. n=10 in each group, all animals were treated for 8 weeks. The cardiac collagen deposition was observed by Masson staining, protein expressions of cardiac collagen types I, III, IV and transforming growth factorβ1 (TGF-β1), connective tissue growth factor (CTGF) were examined by Western blot analysis.
Results: Compared with Control group, DM group showed increased protein expressions of cardiac collagen types I and III, up-regulated expressions of TGF-β1 and CTGF, P<0.05;while the expressions of collagen type IV were similar between 2 groups. Compared with DM group, DM+NaHS group presented reduced cardiac collagen expression, decreased expression of collagen types I and III, down-regulated expressions of TGF-β1 and CTGF, P<0.05;while the expressions of collagen type IV were similar between 2 groups.
Conclusion: H2S may improve the myocardial collagen remodeling in experimental DM rats, the mechanism might be related to the down-regulation of TGF-β1 and CTGF expression.

Objective To explore the effects of hydrogen sulfide (H2S) on myocardial fibrosis and expressions of MAPK1/3 and MMP-8 in diabetic rats. Methods Forty adult male SD rats were randomized into 4 groups, namely the control group, diabetes mellitus group (STZ group), diabetes mellitus with H2S treatment group (STZ+H2S group), and normal rats with H2S treatment group (H2S group). Diabetes was induced by intraperitoneal injections of 40 mg/kg streptozotocin (STZ). The rats in the control group received daily intraperitoneal injections of saline, and those in STZ+H2S group and H2S group were given NaHS (100μmol/kg) injections. After 8 weeks, the pathologies of cardiac fibrosis were examined with HE staining, and the expressions of collagen I, MAPK1/3 and MMP-8 were analyzed with Western blotting. Results Compared with the control group, the diabetic rats showed increased collagen content and obvious interstitial fibrosis in the myocardial tissue with significantly increased expression levels of collagen I, MAPK1/3 and MMP-8 (P<0.05); all these changes were obviously reversed by treatment with H2S (P<0.05). Collagen I, MAPK1/3 and MMP-8 expression levels and the degree of myocardial fibrosis were comparable between H2S group and control group (P>0.05). Conclusion Hydrogen sulfide can attenuate cardiac fibrosis in diabetic rats, and the mechanism may involve the inhibition of MAPK1/3/MMP-8 signal pathway.

Objective To explore the effects of hydrogen sulfide (H2S) on myocardial fibrosis and expressions of MAPK1/3 and MMP-8 in diabetic rats. Methods Forty adult male SD rats were randomized into 4 groups, namely the control group, diabetes mellitus group (STZ group), diabetes mellitus with H2S treatment group (STZ+H2S group), and normal rats with H2S treatment group (H2S group). Diabetes was induced by intraperitoneal injections of 40 mg/kg streptozotocin (STZ). The rats in the control group received daily intraperitoneal injections of saline, and those in STZ+H2S group and H2S group were given NaHS (100μmol/kg) injections. After 8 weeks, the pathologies of cardiac fibrosis were examined with HE staining, and the expressions of collagen I, MAPK1/3 and MMP-8 were analyzed with Western blotting. Results Compared with the control group, the diabetic rats showed increased collagen content and obvious interstitial fibrosis in the myocardial tissue with significantly increased expression levels of collagen I, MAPK1/3 and MMP-8 (P<0.05); all these changes were obviously reversed by treatment with H2S (P<0.05). Collagen I, MAPK1/3 and MMP-8 expression levels and the degree of myocardial fibrosis were comparable between H2S group and control group (P>0.05). Conclusion Hydrogen sulfide can attenuate cardiac fibrosis in diabetic rats, and the mechanism may involve the inhibition of MAPK1/3/MMP-8 signal pathway.