Impact of endocrine disrupting chemicals on semen quality / 中华男科学杂志

Endocrine disrupting chemicals (EDCs) are natural or man-made agents that interfere in some way with human or animal normal endocrine function, and even influence the endocrine function of their offspring. There are many kinds of EDCs, which are widely present in soil, water, and even food. This review elaborates the impact of EDCs on human and animal semen quality from the viewpoint of epidemiology and biology by focusing on pesticides, plasticizers and detergents.

Study on genetic polymorphism of human mismatch repair gene hMLH1 and susceptibility of papillary thyroid carcinoma in Chinese Han people / 中华预防医学杂志

<p><b>OBJECTIVE</b>To explore the associations between the single nucleotide polymorphism of human mismatch repair gene hMLH1 and the papillary thyroid carcinoma (PTC) in Chinese Han people.</p><p><b>METHODS</b>A hospital based 1:1 matched case-control study was carried out. The single nucleotide polymorphism (-93G > A, 1151T > A and 655A > G) for 204 pairs of cases with PTC as well as healthy controls was identified by PCR-RFLP, PCR-ASO and DNA sequencing.</p><p><b>RESULTS</b>With univariate analysis, we found that compared to 1151TT genotype, the TA genotype could increase the PTC risk marginally, with odds ratio (OR) of 2.15 (95%CI: 0.99 - 4.85); While the mutant genotype TA + AA could increase the PTC risk statistically significant, with OR of 2.15(95%CI: 1.02 - 4.69). With 2 x 4 cross-over study, we found that compared to -93GG and 1151TT genotypes, individuals with both -93GA + AA and 1151TA + AA could increase the PTC risk marginally, with OR of 2.50 (95%CI: 0.96 - 6.67); While, compared to 655AA and 1151TT genotypes, individuals with both 655AA and 1151TA + AA could increase the PTC risk statistically significant, with OR of 2.50 (95%CI: 1.02 - 4.73). Multivariate and conditional logistic regression analysis showed the genotype of 1151TA, the history of receiving CT diagnosis, the history of tumor, the negative life events and eating seafood frequently could increase the risk of PTC, with OR of 6.79 (95%CI: 3.18 - 14.49), 3.35 (95%CI: 1.93 - 5.80), 39.03 (95%CI: 3.70 - 41.60) and 3.98 (95%CI: 1.81 - 8.73); While, eating fruit frequently could decrease the PTC risk.</p><p><b>CONCLUSION</b>The 1151TA + AA genotype, the history of receiving CT diagnosis, the history of tumor, the negative life events and eating seafood frequently were the risk factors of PTC, while eating fruit frequently was the protective factor.</p>

Association of genetic polymorphisms and haplotypes in hMLH1 and hMSH3 gene with the risk of papillary thyroid carcinoma / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To explore the relationship of the genetic polymorphisms and the haplotypes in hMLH1 and hMSH3 gene with the risk of papillary thyroid carcinoma (PTC) in Chinese Hans.</p><p><b>METHODS</b>A hospital based 1:1 matched case-control study was carried out. The polymorphisms for 204 pairs of PTC cases and healthy controls were identified by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and allele specific oligonucleotide (PCR-ASO) assays.</p><p><b>RESULTS</b>(1) The PTC risk was marginally increased in the hMLH1 1151TA genotype, with odds ratio (OR) of 2.15 (95%CI: 0.99-4.85); the PTC risk was significantly increased in the mutant genotype 1151TA+AA, with OR of 2.15 (95%CI: 1.02-4.69); (2) The haplotypes of -93G, 1151A, 655A in the hMLH1 gene could increase the PTC risk, with OR of 2.67 (95%CI: 1.16-6.53, P=0.011), compared with the haplotype of -93G, 1151T, 655A; (3) Compared to 3124A, 2835G haplotype in hMSH3 gene, the 3124G, 2835A haplotype could increase the PTC risk marginally, with OR of 3.08 (95%CI: 0.92-13.25).</p><p><b>CONCLUSION</b>The 1151T/A polymorphism in hMLH1 was associated with PTC; both the haplotype of -93G, 1151A, 655A in hMLH1 and the 3124G, 2835A haplotype in hMSH3 were associated with PTC.</p>

A matched case-control study of papillary thyroid carcinoma / 中华流行病学杂志

<p><b>OBJECTIVE</b>In order to explore the risk factors of the papillary thyroid carcinoma(PTC), a hospital-based matched case-control study was carried out in Shanghai.</p><p><b>METHODS</b>Matched by gender, age (+/- 3 years old) and native place,205 pairs of cases and controls were recruited and studied. Database was established with Epi Info 6.0 software. Univariate and multivariate conditional logistic regression analysis were carried out with SPSS 11.5 software.</p><p><b>RESULTS</b>Data from multivariate conditional logistic regression analysis showed that often drinking tea and having better economic living standard 20 years ago were protective factors of PTC, with ORs of 0.456 and 0.221 respectively. Personal history of CT examination, familial history of cancer and the mother's age was older than 22 years when the research subject was delivered, were risk factors of PTC, with ORs of 12.935, 7.027 and 3.729 respectively. Results data from multivariate analysis on female subjects showed that the history of CT examination, mother's age was older than 22 (when the subject was delivered) and the history of gynecological disease were the risk factors of PTC,with ORs of 107.453,29.246 and 59.521 respectively. Taking bean products frequently and having higher standard of living 20 years ago were the protective factors of PTC,with ORs of 0.025 and 0. 144 respectively.</p><p><b>CONCLUSION</b>History of CT examination, familial history of cancer and the mother's age(older than 22 when the subject was delivered) were the risk factors of PTC. Frequent tea drinking habit and having higher standard of living 20 years ago were the protective factors of PTC. History of CT examination,mother's age (older than 22 when the subject was delivered) and the history of gynecological disease appeared the risk factors of PTC for women. Habit on frequent bean products taking and had higher standard of living 20 years ago were the protective factors of PTC to women.</p>

Single nucleotide polymorphisms and point mutations of ataxia telangiectasia mutated gene in Chinese of Han ethnicity / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To explore the single nucleotide polymorphisms (SNPs) and point mutations of ataxia telangiectasia mutated (ATM) gene in Chinese of Han ethnicity.</p><p><b>METHODS</b>The target fragments of the exon 39, exon 61 and exon 63 of ATM gene were first amplified using PCR technique, then screened for the SNPs and point mutations using single strand conformation polymorphism (SSCP) technique, finally the representative bands were sequenced for the verification of the new single nucleotide polymorphisms and point mutations using the automatic DNA sequencing technique.</p><p><b>RESULTS</b>Six new SNPs were found in the exon 39, intron 61 and intron 63 of ATM gene. They are respectively the A/T polymorphisms at nucleotide 5689 and 5691 in exon 39, the T/G polymorphisms at nucleotide +69 and +99, the A/G polymorphism at nucleotide +94 in intron 61, the G/C polymorphism at nucleotide +17 in intron 63. Five new point mutations were found in the exon 61, intron 62 and exon 63 of ATM gene. They are respectively the T/G transversion at nucleotide 8618 in exon 61, the T/G transversion at nucleotide -13 in intron 62, the T/G transversion at nucleotide 8793, the G/A transitions at nucleotide 8816 and 8848 in exon 63. The known three SNPs, the G/A polymorphism at nucleotide 5557 in exon 39, the T/C polymorphism at nucleotide +104 in intron 61 and the T/C polymorphism at nucleotide -55 in intron 62, were verified in Chinese of Han ethnicity.</p><p><b>CONCLUSION</b>There are great differences in the SNPs of ATM gene between Chinese of Han ethnicity and Caucasian.</p>

Genetic polymorphisms in X-ray repair cross-complementing gene 1 and susceptibility to papillary thyroid carcinoma / 中华流行病学杂志

<p><b>OBJECTIVE</b>To study the association of polymorphisms in the X-ray repair cross-complementing gene 1 (XRCC1) and papillary thyroid carcinoma (PTC).</p><p><b>METHODS</b>A hospital based, matched case-control study was carried out. The polymorphisms in XRCC1 for 105 pairs of cases with PTC and controls were identified by PCR-RFLP.</p><p><b>RESULTS</b>The frequencies of Arg/Arg, Arg/Trp and Trp/Trp genotypes at XRCC1 Arg194Trp site were 47.6%, 49.5% and 2.9% among cases compared to 45.7%, 48.6% and 5.7% among controls. There was no statistically significant difference between the two groups (chi(2) = 1.07, P = 0.59). The frequencies of Arg/Arg, Arg/Gln and Gln/Gln genotypes at XRCC1 Arg399Gln site were 46.7%, 41.9% and 11.4% among cases, while 54.2%, 42.9% and 2.9% among controls respectively. There was statistically significant difference between the two groups (chi(2) = 6.40, P = 0.04). Individuals with Gln/Gln genotype had a 3.65-fold increased risk of developing PTC compared to Arg/Arg genotype (OR = 4.65, 95% CI: 1.24 - 17.45). The multivariate conditional logistic regression analysis showed that the XRCC1 Arg399Gln polymorphism, negative life events and X-irradiation history were associated with PTC, with odds ratios of 2.71 (95% CI: 1.22 - 6.05), 5.34 (95% CI: 1.40 - 20.38) and 0.38 (95% CI: 0.12 - 0.72) respectively. However, XRCC1 Arg194Trp polymorphism, drinking tea, fruit and economic levels did not show statistically significant associations with PTC.</p><p><b>CONCLUSION</b>The Gln/Gln genotype at XRCC1 Arg399Gln site and negative life events significantly increased while X-irradiation history decreased the risk of developing PTC.</p>