Association between long-term ambient air pollution exposure and the risk of breast cancer: a systematic review and meta-analysis.

Breast cancer is a complex and multifactorial disease which stems significantly from both environmental and genetic factors. A growing number of epidemiological studies have suggested that ambient air pollution (AAP) exposure may play an important role in breast cancer development. However, no consistency has been reached concerning whether high levels of air pollutant exposure were related to increased breast cancer risk among the current evidence. To further clarify such association of long-term AAP exposure with risk of breast cancer, a systematic review and meta-analysis of available evidence was performed. An extensive literature search in 3 academic databases was conducted before March 10, 2020. The risk of bias (RoB) for each individual study was evaluated with a domain-based assessment tool, developed by the National Toxicology Program/Office of Health Assessment and Translation (NTP/OHAT). Meta-estimates for air pollutant-breast cancer combinations were calculated for a standardized increment in exposure by random-effect models. The confidence level in the body of evidence and the certainty of evidence was also assessed for each air pollutant-breast cancer combination. The initial search identified 5446 studies, and 18 of them were eligible. The pooled analysis found an increased risk of breast cancer was associated with an increase in each 10 µg/m3 in nitrogen dioxide (NO2) exposure (hazard ratio (HR) = 1.02, 95% confidence interval (CI) = 1.01, 1.04), while particulate matter with aerodynamic diameters ≤ 2.5 µm and 10 µm (PM2.5, PM10) revealed no statistically significant associations with breast cancer risk. Our evaluation on the certainty of evidence indicates that there was a "moderate level of evidence" in the body of evidence for an association of NO2 exposure with an increased breast cancer risk and an "inadequate level of evidence" in the body of evidence for an association of PM2.5 and PM10 exposure with an increased breast cancer risk. Our study suggests long-term exposure to NO2 is related to an increased risk of breast cancer. However, in consideration of the limitations, further studies, especially performed in developing countries, with improvements in exposure assessment, outcome ascertainment, and confounder adjustment, are needed to draw a definite evidence of a causal relationship.

Investigation on factors related to uterine fibroids in rural women of northern Anhui province.

AIM: Given the increasing prevalence of hysteromyoma among the Chinese rural women of childbearing age, it is imperative that more attention should be given to researching risk factors that predispose women to this condition so that early preventive measures may be taken. Our study investigates potential risk factors for uterine fibroids such as participants' demographic characteristics (age, ethnicity, education), physiological characteristics (age at menarche, primiparous age), and the occurrence of several different female reproductive diseases (vaginitis, pelvic inflammatory disease). METHODS: 2200 rural women of reproductive age were screened from a cross-sectional study carried out in the northern Anhui province. Data were collected by questionnaire surveys, gynecological and laboratory examinations and were subjected to univariate and multivariate analysis to evaluate the risk factors for uterine fibroids. RESULTS: Of the 2200 women, 440 had uterine fibroids. In general, women with endometriosis, ovarian cysts and early menarche were more likely to suffer from hysteromyoma. Factors including higher parity, late age of first childbirth, and a regular menstrual cycle were associated with the reduced risk of uterine fibroids. CONCLUSIONS: Our findings indicate that parameters such as earlier age of menarche, early primiparous age, lower parity and a variety of female reproductive diseases were associated with an increased risk of uterine fibroids. These findings may be used to guide the formulation of effective prevention and intervention protocols to improve the reproductive health of rural women.

[Treatment of sacroiliac joint dislocation by Zhuang medicine tendon therapy combined with chiropractic manipulation].

OBJECTIVE: To analyze the clinical effect of Zhuang medicine tendon therapy combined with chiropractic manipulation in treating sacroiliac joint dislocation. METHODS: From January 2017 to May 2018, 60 patients with sacroiliac joint dislocation were divided into treatment group and control group according to the order of admission. There were 19 males and 11 females in the treatment group, aged from 23 to 52 (38.97±3.23) years old, with a course of 2 h to 5.1 months, with an average of (2.19±1.12) months. There were 14 males and 16 females in the control group, aged from 26 to 50 (39.07±3.30) years old, with a course of 3 h to 6 months, with an average of(2.41±1.05) months. The treatment group was treated with Zhuang medicine tendon therapy combined with chiropractic manipulation, while the control group was treated with conventional acupuncture and massage. Before treatment, the main clinical symptoms of the patients were lumbosacral pain, posterior superior iliac spine not at the same level and accompanied with dyskinesia. The pelvic separation test and the "4" test were positive. After treatment, the curative effect was evaluated according to the improved Macnab standard and the "score of treatment of lumbar diseases". RESULTS: Sixty patients were followed up for an average of 8 months. At the latest follow-up, the clinical effect of modified Macnab was better in the treatment group than in the control group(P<0.01). After treatment, the treatment group was better than the control group on lumbar function score (P<0.01). CONCLUSIONS: The treatment of sacroiliac joint dislocation by Zhuang medicine tendon therapy combined with chiropractic manipulation has good clinical effect and is worth further application and development.

Effects of stomatal development on stomatal conductance and on stomatal limitation of photosynthesis in Syringa oblata and Euonymus japonicus Thunb.

During leaf development, the increase in stomatal conductance cannot meet photosynthetic demand for CO2, thus leading to stomatal limitation of photosynthesis (Ls). Considering the crucial influences of stomatal development on stomatal conductance, we speculated whether stomatal development limits photosynthesis to some extent. To test this hypothesis, stomatal development, stomatal conductance and photosynthesis were carefully studied in both Syringa oblata (normal greening species) and Euonymus japonicus Thunb (delayed greening species). Our results show that the size of stomata increased gradually with leaf expansion, resulting in increased stomatal conductance up to the time of full leaf expansion. During this process, photosynthesis also increased steadily. Compared to that in S. oblata, the development of chloroplasts in E. japonicus Thunb was obviously delayed, leading to a delay in the improvement of photosynthetic capacity. Further analysis revealed that before full leaf expansion, stomatal limitation increased rapidly in both S. oblata and E. japonicus Thunb; after full leaf expansion, stomatal limitation continually increased in E. japonicus Thunb. Accordingly, we suggested that the enhancement of photosynthetic capacity is the main factor leading to stomatal limitation during leaf development but that stomatal development can alleviate stomatal limitation with the increase of photosynthesis by controlling gas exchange.