Association between breast cancer and hepatitis C: A joint study of hospitalized patients and nationwide cohorts

Whether hepatitis C virus (HCV) infection is associated with breast cancer risk remains elusive, and we aimed to elucidate it. A nationwide population-based cohort study of the Taiwan National Health Insurance Research Database (TNHIRD) was conducted. Additionally, breast cancer risk factors, and HCV core expression were surveyed in breast cancer patients of a tertiary care center. Three TNHIRD cohorts (1:4:4, propensity score-matched, 2003-2012), including HCV-treated (3646 HCV-infected females with interferon-based therapy ≥6 months), HCV-untreated (n = 14,584) and HCV-uninfected (n = 14,584) cohorts, were enrolled. The HCV-untreated cohort had the highest 9-year breast cancer cumulative incidence (2.017%; 95% confidence interval [CI]: 1.382%-2.846%), while the HCV-treated (1.073%; 0.414%-2.356%), and HCV-uninfected (1.453%; 0.785%-2.486%) cohorts showed no difference. Untreated HCV infection (hazard ratio [HR]: 1.701; 95% CI: 1.205%-2.400), urban residency (1.658, 1.183-2.323), and baseline cardiovascular events (1.920; 1.005-3.668) were associated with incident breast cancers. The interaction analysis showed that particularly among patients <49 years, HCV infection was associated with breast cancer development (2.193; 1.097-4.384). Of 12,170 hospitalized breast cancer patients, 4.90% were HCV Ab-positive. HCV Ab-positive patients were older (60.92+/-10.82 vs 53.91+/-11.38 years, P < 0.0001) and had a higher body mass index (25.39+/-5.1 vs 24.5+/-4.3 kg/m², P = 0.007), rates of diabetes (30.60 vs 19.98%, P < 0.0001), hypertension (46.9 vs 30.39%, P < 0.0001), dyslipidemia (25.52 vs 20.28%, P = 0.031), and hyperuricemia (11.38 vs 5.52%, P < 0.0001) than their counterparts. No HCV core-positive cells were demonstrated in breast cancer tissues. Conclusions: Untreated HCV infection, urbanization, and cardiovascular events were potential risk factors for breast cancer. The HCV-associated risk was most prominent among patients <49 years, might not be associated with in situ HCV core-related oncogenesis but with metabolic alterations, and was reversed by anti-HCV therapy.

Report of the consensus conference on diagnostic criteria of ALI/ARDS at high altitudes in Western China

China is a mountainous country. The Qing-Zang plateau, Yun-Gui plateau, and Yellow Land plateau, which are known as the world's ridge, are located in the west of China. The highland area over 3,000 m in height occupies one-sixth of the land area of China and half the highland area of the world. About 60-80 million people live in the regions where the elevation ranges from 1,500 m to 4,000 m. In the latter half of the last century, the influence of complex environmental factors on the human body, such as low oxygen pressure, cold climate, strong radiation, high wind speed, and super-evaporation, were studied in an extensive and profound way and formed an important field of altitude medicine. For a long time, many researchers have carried out investigations related to the systemic inflammatory response syndrome (SIRS), acute respiratory distress syndrome (ARDS), and multiple organ dysfunction syndrome (MODS) and its pathophysiological mechanism initiated by cytokines and mediators, regarding which many problems are still unclear. However, systematic research into the mechanism from SIRS to ARDS to MODS in the highlands remains blank. The diagnostic criteria of ALI/ARDS in the highlands are quite different from that in the plain, and thus was a central topic for discussion at this meeting.

Genotoxicity of heated cooking oil vapors

Epidemiological studies of lung cancer in Chinese women indicated that factors other than cigarette smoking are related to lung cancer risk. A case-control study suggested that indoor air pollution, particularly from cooking oil emissions, may be involved. Condensates of volatile emissions from rapeseed and soybean cooking oils were prepared and found to be genotoxic in short-term tests including the Salmonella mutation assay, SV50 forward-mutation assay, and sister-chromatid exchange assay, as well as the micronucleus assay in mouse bone marrow. In contrast, condensates from rapeseed oil with butylated hydroxyanisole or hydrogenated rapeseed oil were not mutagenic, implicating oxidation products as the cause for mutagenicity. Peanut oil and lard condensates were not mutagenic in any assay. The association of exposure to Chinese rapeseed cooking-oil emissions and lung-cancer risk may be related to the mutagenic component of these condensates.

Synergistic and antagonistic effects on genotoxicity of chemicals commonly found in hazardous waste sites

Synergistic and antagonistic effects on genotoxicity of mixtures of four chemicals; i.e., lead tetraacetate (LTA), arsenic trioxide (ATO), dieldrin (DED), and tetrachloroethylene (TCE), were evaluated by the Tradescantia-micronucleus (Trad-MCN) assay. The chemicals were mixed in ratios of 1:1, 1:2 and 2:1 for mixtures of two chemicals and 1:1:1 each for three chemicals. The concentration of stock solution of these chemicals was around the minimum effective dose (MED) or below the MED for these chemicals as reported by Sandhu et al. (1989). Treatments were applied to plant cuttings by hydroponic uptake of the mixed solutions through the stems of the plant for 30 h followed by fixation of the flower buds in aceto-alcohol (1:3 ratio) without a recovery period. Microslides were prepared for scoring MCN frequencies. Results of two series of repeated experiments indicated that all mixtures of LTA/ATO exhibited antagonistic effects. On the other hand, all mixtures of TCE and DED exhibited synergistic effect. These data indicate that for evaluating biological hazards at chemical waste sites, it is prudent to evaluate the genotoxicity of complex chemical mixtures as these exist in nature because the biological effects based on evaluating individual chemicals may not be true predictors of the interactive effects of the pollutants.