Protective effect of ethyl acetate extract from Bidens bipinnata on hepatocyte damage induced by endoplasmic reticulum stress / 中国中药杂志

To explore the protective effect and mechanism of ethyl acetate extract from Bidens bipinnata on hepatocyte damage induced by endoplasmic reticulum stress. Tunicamycin was used to establish the damage model in L02 cells. Methyl thiazolyl tetrazolium(MTT) colorimetric assay was used to investigate the survival rate of ethyl acetate extract from B. bipinnata in L02 cells injury induced by endoplasmic reticulum stress; the protein expressions of endoplasmic reticulum stress-related molecule glucose regulated protein 78(GRP78), PKR-like ER kinase(PERK), eukaryotic initiation factor-2(eIF2α), activating transcription factor 4(ATF4), C/EBP homologous protein(CHOP), B-cell CLL/lymphoma 2(Bcl-2), Bal-2 associated X apoptosis regulator(Bax) were examined by Wes-tern blot. The expressions of the above proteins were also detected after endoplasmic reticulum stress inhibitor(4-phenyl butyric acid) and CHOP shRNA-mediated knockdowns were added. The expressions of GRP78, PERK, CHOP in L02 cells were observed by immunofluorescence method. The results showed that ethyl acetate extract from B. bipinnata could significantly increase the survival rate of L02 cell injury caused by endoplasmic reticulum stress in a dose and time-dependent manner(P<0.05 or P<0.01). The expression levels of GRP78, PERK, eIF2α, ATF4, CHOP and Bax in the drug treatment groups were significantly down-regulated(P<0.05 or P<0.01), while Bcl-2 was significantly up-regulated(P<0.01). After endoplasmic reticulum stress inhibitor and CHOP shRNA-mediated knockdowns were added, the expression levels of GRP78, PERK, eIF2α, ATF4, CHOP, Bax in the drug treatment groups were significantly down-regulated(P<0.01), whereas Bcl-2 was significantly up-regulated(P<0.01). Immunofluorescence results showed that the expressions of GRP78, PERK, CHOP were consistent with the Western blot method. In conclusion, ethyl acetate extract from B. bipinnata has a significant protective effect on the damage of L02 cells caused by endoplasmic reticulum stress. The mechanism may be related to the inhibition of endoplasmic reticulum stress and the down-regulation of apoptosis in cells through the PERK/eIF2α/ATF4/CHOP signaling pathway.

Relationship between organochlorine pollution in soil and rice and the incidence of colorectal cancer in Jiashan county, Zhejiang province / 中华流行病学杂志

<p><b>OBJECTIVE</b>To study the relationship between organochlorine and colorectal cancer.</p><p><b>METHODS</b>With multistage cluster random sampling, 11 towns were drawn based on the standardized incidence of colorectal cancer. Administrative and natural villages were drawn subsequently. Rice and soil samples in the paddy fields were collected in the villages. The contents of organochlorine were detected. Rank correlation analysis was performed together with the data of colorectal cancer incidence.</p><p><b>RESULTS</b>The contents of hexachlorocyclohexane (HCH) and dichlorodiphenyltrichloroethane (DDT) in both rice and soil samples were below the amounts of the country. Statistics showed that the standardized incidence rates were significantly different among the 11 towns. The contents of delta-HCH, gamma-HCH, sodium pentachlorophenate in rice and those of delta-HCH in soil were statistically different among the towns through the rank sum test. The standardized incidence of colorectal cancer was significantly connected with the content of total DDT in rice while rectal cancer with total DDT and PP'-DDE and colon cancer with 1245 of polychlorinated biphenyl (PCBs). The correlation coefficients were 0.636, 0.691, 0.716 and 0.658 respectively (P < 0.05).</p><p><b>CONCLUSIONS</b>Rectal cancer was statistically correlated with organochlorine, mainly for total DDT and dichlorodiphenyldichloroethylene (PP'-DDE). Colon cancer was significantly associated with 1245 of PCBs. Further study should be performed since this research was only an ecological study.</p>

A comparative study on iodine nutritional status of adult islanders in Zhoushan / 中华流行病学杂志

<p><b>OBJECTIVE</b>To measure the iodine nutritional status on adult islanders and to evaluate the advantages and disadvantages of iodized salt prophylactic programs.</p><p><b>METHODS</b>A comparative study was carried out in 8 rural townships selected from Dinghai (iodized salt district) and Daishan (non-iodized salt district) of Zhoushan islands by random sampling method. Mann-Whitney test was used to compare the urinary iodine concentration and dietary iodine intake of the two groups. Spearman correlation test was used to look for the correlation of urinary iodine concentration and dietary iodine intake in the two groups respectively.</p><p><b>RESULTS</b>The amounts of daily iodine intake excluding the iodine intake from iodized salt in the two groups were 128 micro g and 147 micro g respectively but the difference was not statistically significant (u = 1.847, P = 0.065). The urinary iodine concentration of non-iodized salt group was 90 micro g/L, lower than 194 micro g/L in iodized salt group (u = 14.673, P = 0.000). There was no significant correlation between daily iodine intake and urinary iodine concentration (r(s) = 0.052, P = 0.095).</p><p><b>CONCLUSIONS</b>In Zhoushan islands, the daily iodine intake did not meet the daily need (150 micro g/day) suggesting that iodized salt supplement was necessary. However, side effect due to overdose should be brought into attention.</p>