Objective To explore the relationship between MspⅠpolymorphism of CYP1A1 gene and susceptibility to breast cancer in Yi nationality in Yunnan province. Methods The gene polymorphism of restriction enzyme of 3′-terminal of CYP1A1 was detected by PCR-RFLP in 60 healthy Yi women , 51 Yi women with breast cancer, 235 healthy Han women, and 250 Han women with breast cancer. Results The distribution frequency of CYP1A1-MspⅠgenotypes was significantly higher in Yi women with breast cancer (51.0%) than in the healthy Yi women (33.3%) (P < 0.05), an the allele C had a higher frequency in women with breast cancer than in healthy controls (P < 0.05). Significant differences of frequencies were found in genotypes TT, TC and CC between women with breast cancer and healthy controls (P < 0.05). The risks of TC and CC for breast cancer were 1.19 and 1.95 folds respectively to TT genotype. But as compared with Yi women , the distribution frequency of CYP1A1-MspⅠ genotypes did not differ between Han women with breast cancer and in the healthy control (P > 0.05), and there were no differences in three genotype frequencies (P > 0.05). Conclusions Gene polymorphism of CYP1A1 genotypes may be associated with the risk of breast cancer in Yi nationality but not in Han nationality in Yunnan. The mutation of CYP1A1 gene may increase the incidence of breast cancer in Yi nationality.

OBJECTIVETo estimate the frequency of daily average PM10 concentrations exceeding the air quality standard (AQS) and the reduction of particulate matter emission to meet the AQS from the statistical properties (probability density functions) of air pollutant concentration.

METHODSThe daily PM10 average concentration in Beijing, Shanghai, Guangzhou, Wuhan, and Xi'an was measured from 1 January 2004 to 31 December 2008. The PM10 concentration distribution was simulated by using the lognormal, Weibull and Gamma distributions and the best statistical distribution of PM10 concentration in the 5 cities was detected using to the maximum likelihood method.

RESULTSThe daily PM10 average concentration in the 5 cities was fitted using the lognormal distribution. The exceeding duration was predicted, and the estimated PM10 emission source reductions in the 5 cities need to be 56.58%, 93.40%, 80.17%, 82.40%, and 79.80%, respectively to meet the AQS.

CONCLUSIONAir pollutant concentration can be predicted by using the PM10 concentration distribution, which can be further applied in air quality management and related policy making.

Air Pollutants ; analysis ; China ; Cities ; Environmental Monitoring ; Likelihood Functions ; Particulate Matter ; analysis

BACKGROUND:In vitro fertilization-embryo transfer is commonly used to solve infertility,but its success rate is not high,the more common reasons are poor endometrial receptivity,poor egg quality,etc.The follicular fluid melatonin can inhibit the aging of the ovary,to a certain extent,can promote the development of embryos,improve the probability of conception,but whether there is a correlation between the two is not known. OBJECTIVE:To explore the correlation between follicular fluid melatonin level and pregnancy rate of single-cycle in vitro fertilization-embryo transfer women. METHODS:A total of 112 female patients who received in vitro fertilization-embryo transfer treatment in the First Affiliated Hospital of Anhui Medical University from December 2020 to April 2021 were selected as the study subjects.They were divided into quartile array(Q1-Q5)according to the follicular fluid melatonin level from low to high.Among them,the melatonin level of group Q1 was<6.99 ng/L(n=18),that of group Q2 was 7.00-9.99 ng/L(n=26),that of group Q3 was 10.00-11.99 ng/L(n=27),and that of group Q4 was 12.00-13.99 ng/L(n=18);and melatonin levels in group Q5 were 14.00-19.99 ng/L(n=23).Clinical data characteristics of the five groups were compared.Multi-factor Logistic regression was used to analyze the correlation between follicular fluid melatonin level and pregnancy rate of women with single-cycle in vitro fertilization-embryo transfer and embryo transfer.A restricted cubic spline Logistic regression model was established to analyze the dose-response relationship,and the model was evaluated by clinical decision curve. RESULTS AND CONCLUSION:(1)Compared with the study population with the lowest melatonin quintile(Q1),with the increase of melatonin level(Q2-Q5),the levels of egg harvest and pregnancy success were gradually increased,and the body mass index was gradually decreased,and the differences were significant(P<0.05).(2)Multivariate Logistic regression analysis showed that after adjusting for confounding factors such as global mass index,number of eggs retrieved,luteinizing hormone,estradiol,progesterone and other confounding factors,follicular fluid melatonin level was still independently correlated with pregnancy rate of single-cycle in vitro fertilization-embryo transfer women(OR=1.538,95%CI:1.032-1.837,P<0.05),and there was significant difference in trend test of follicular fluid melatonin level from low to high quintile array(Ptrend<0.05).(3)The sensitivity test analysis showed that E value was 2.117.Subgroup analysis showed that the study population with higher levels of luteinizing hormone in follicular fluid had a more significant association between follicular fluid melatonin and pregnancy rate in single-cycle in vitro fertilization-embryo transfer women(P interaction=0.008).(4)The results of restricted cubic spline model analysis showed that there was a nonlinear dose-response relationship between follicular fluid melatonin level and pregnancy rate of single-cycle in vitro fertilization-embryo transfer women(P<0.05),and there was an overall positive correlation between follicular fluid melatonin level and pregnancy rate of single-cycle in vitro fertilization-embryo transfer women.(5)The results of clinical decision curve analysis showed that the follicular fluid melatonin level had important clinical value in predicting the pregnancy rate of single-cycle in vitro fertilization-embryo transfer women.(6)Follicular fluid melatonin level is closely related to the pregnancy rate of single-cycle in vitro fertilization-embryo transfer women,and with the decrease of follicular fluid melatonin level,the pregnancy rate of single-cycle in vitro fertilization-embryo transfer women also decreases.