Exosomes Derived from Hydroquinone-transformed Human Bronchial Epithelial Cells Inhibited Recipient Cell Apoptosis by transferring miR-221 / 生物医学与环境科学（英文）

Objective@#Although benzene is a confirmed environmental carcinogen, the mechanism of its carcinogenicity remains largely unclear. The suggested oncogene, miR-221, is elevated and plays important roles in various tumors, but its role in benzene-induced carcinogenesis remains unknown.@*Methods@#In the present study, we constructed hydroquinone (HQ, a representative metabolite of benzene with biological activity)-transformed malignant cell line (16HBE-t) and analyzed the level of miR-221 in it with qRT-PCR. Exosomes from 16HBE-t cells incubated with or without an miR-221 inhibitor were isolated by ultracentrifugation, characterized by transmission electron microscopy and laser scanning confocal microscope, and then transfected into 16HBE cells. The effects of exosomal miR-221 on apoptosis induced by HQ in recipient cells were determined using flow cytometry.@*Results@#The amount of miR-221 in 16HBE-t was significantly increased compared with controls. When recipient cells ingested exosomes derived from 16HBE-t, miR-221 was increased, and apoptosis induced by HQ was inhibited. Blocking miR-221 in 16HBE-t using an inhibitor did not significantly alter miR-221 or apoptosis in recipient cells.@*Conclusion@#Exosomal miR-221 secreted by 16HBE-t inhibits apoptosis induced by HQ in normal recipient cells.

Epidemiological study on hyperuricemia and gout in Foshan areas, Guangdong province / 中华流行病学杂志

Objective To determine the prevalence rates and risk factors of hyperuricemia(HUA) and gout among residents aged over 20 years in Foshan areas. Methods A randomly stratified cluster sampling was conducted, and 7403 inhabitants were investigated on their prevalence rates of HUA and gout. Results (1) The prevalence of HUA was 15.09%, and the standardized rate was 15.27%, in which the prevalence in males was 19.90% and females was 10.54%. The prevalence of gout was 1.04% and the standardized rate was 1.08%,in which the prevalence in males was 1.73%and females was 0.39%. The prevalence of gout in patients with HUA was 6.89%. (2) Average serum uric acid was (336.4 ± 81.5) μmol/L, with (347.1 ± 88.6) μmol/L in males and (289.7±78.6) μmol/Lin females. The serum uric acid levels in male patients with HUA was higher than those in women.(3) Age, body mass index, systolic blood pressure, diastolic blood pressure, serum uric acid, blood sugar, triglyceride (TG), total cholesterol were significantly higher in patients with HUA and gout than in the normal group (P＜0.05-0.01). The incidence rates of patients with hyperuricemia and gout in the following indices as: overweight and obesity, high blood pressure, high blood sugar were significantly higher than those in the normal group (P＜0.05). Patients having gout in the following indices as age, TG, serum uric acid levels were significantly higher than the HUA group (P＜0.05).(4) Data from non-conditional logistic regression analysis showed that age, overweight, hypertension,diabetes, hyperlipidemia, use of diuretics, family history, alcohol uptake, eating seafood and drinking meat broth, post-menopausal women, and other factors were similar to those factors as patients with hyperuicemia. Tea, fresh vegetables, fruits seemed to be the protective factors. Conclusion Both the prevalence rates of HUA and gout had significantly increased in Foshan areas in recent years.Restricting the intake of food with rich purine, alcohol intake as well as controlling obesity and blood pressure, improving the status of lipid metabolic disorder together with programs as hypertension control etc. were important measures in the strategies on prevention and treatment on hyperuricemia and gout.

Construction of vector of multiple loci gene targeting in leghorn chicken based on BAC with Cre/lox P system / 生物工程学报

Based on the sequence of BAC (Bacterial Artificial Chromosome) along with the Cre/lox P system, the gene-targeting vectors to multiple loci of the repetitive internal transcribed spacers between rDNA genes in Leghorn chicken were constructed. The key material of multiple loci gene targeting in vivo would be obtained. First, the plasmid of pYLSV-TDN with TK, HRDS2, and Neo genes was constructed. The TK-HRDS2-Neo DNA fragment obtained from the plasmid of pYLSV-TDN was digested by Not I/HindIII and inserted into the upstream of the lox P site of BAC plasmid for obtaining the selective vector of BAC-TDN. The expression vector of pYLVS-GID with EGFP, hIFN genes, and HRDS1 was then obtained. The plasmid of BAC-TDN-VS-GID was obtained by cotransformation of the selective vector of BAC-TDN and the expression vector of pYLVS-GID to E. coli NS3529 through the action of Cre/lox P system. The gene-targeting vector of BAC-TDN-GID to multiple loci of the ITS region in Leghorn chicken was obtained by cleaving the sequence of pYLVS with the homing endonuclease of I -Sce I and ligating with the linker of LS. The insertion and the insert direction of DNA fragments were identified by restriction digestion or PCR and sequencing in each clone. The significance of the technique ofgene-targeting vector to multiple loci are shown as follows. First, the targeting loci were increased to 100 - 300. Second, the problems of unstable expression of inserted genes were partially solved. Third, the need for safety against toxicity integration was resolved. Fourth, the forbidden zone of gene integrating on the repetitive DNA sequences was broken through.

Possible role of DNA polymerase beta in protecting human bronchial epithelial cells against cytotoxicity of hydroquinone / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To explore the toxicological mechanism of hydroquinone in human bronchial epithelial cells and to investigate whether DNA polymerase beta is involved in protecting cells from damage caused by hydroquinone.</p><p><b>METHODS</b>DNA polymerase beta knock-down cell line was established via RNA interference as an experimental group. Normal human bronchial epithelial cells and cells transfected with the empty vector of pEGFP-C1 were used as controls. Cells were treated with different concentrations of hydroquinone (ranged from 10 micromol/L to 120 micromol/L) for 4 hours. MTT assay and Comet assay [single-cell gel electrophoresis (SCGE)] were performed respectively to detect the toxicity of hydroquinone.</p><p><b>RESULTS</b>MTT assay showed that DNA polymerase beta knock-down cells treated with different concentrations of hydroquinone had a lower absorbance value at 490 nm than the control cells in a dose-dependant manner. Comet assay revealed that different concentrations of hydroquinone caused more severe DNA damage in DNA polymerase beta knock-down cell line than in control cells and there was no significant difference in the two control groups.</p><p><b>CONCLUSIONS</b>Hydroquinone has significant toxicity to human bronchial epithelial cells and causes DNA damage. DNA polymerase beta knock-down cell line appears more sensitive to hydroquinone than the control cells. The results suggest that DNA polymerase beta is involved in protecting cells from damage caused by hydroquinone.</p>

hPARP1 genetic polymorphism in southern Chinese Han and Miao populations / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To study hPARP1 genetic polymorphism in southern Chinese Han and Miao populations.</p><p><b>METHODS</b>Blood samples from 187 and 210 southern healthy Han and Miao populations were collected. The mutations of exons 12,13,16 and 17 of hPARP1 gene were investigated by PCR-single-strand conformation polymorphism(SSCP).</p><p><b>RESULTS</b>Fragments of 253 bp,313 bp,175 bp,362 bp within exons 12,13,16 and 17 respectively of hPARP1 gene were amplified by multiple PCR. An SSCP variant in exons 12,13,16 and 17 of PARP1 gene in 187 healthy Han and 210 healthy Miao individuals was identified. Seven single-base substitutions compared with the sequence of PARP1 gene were identified: a T to C transition in exon 12 (Phe548Ser), a G to T transition in exon 13 (Ala683Ser), a G to T transition in exon 16 (Asp798Tyr), and a A to G transition in exon 17 (His808Arg).</p><p><b>CONCLUSION</b>There were polymorphism sites in exons 12,13,16,17 of hPARP1 gene in southern Chinese Han and Miao populations; these results may be useful for the establishment of PARP1 genotyping, and these newly described PARP1 alleles would be advantageous indicators for population studies.</p>