Factors associated with blood lead levels in children in Shenyang, China: a cross-sectional study.

BACKGROUND: Although blood lead levels (BLLs) in children are gradually decreasing, low-concentration lead exposure can still exert adverse effects. We studied the factors that affect BLLs in children in Shenyang, China. METHODS: We conducted a cross-sectional study by administering structured questionnaires on family demographics and food intake. The concentrations of lead in venous blood were determined by graphite furnace atomic absorption spectrometry. RESULTS: A total of 273 children aged 1-6 years were enrolled. The geometric mean (geometric standard deviation) of BLLs was 24.94 (12.70) µg/L in boys and 23.75 (11.34) µg/L in girls. The prevalence of BLLs of ≥35 µg/L was 22.7% and was mainly observed in children aged under 3 years. Often hand washing before meals was protective against BLLs ≥20 µg/L (adjusted OR: 0.427, 95%CI: 0.238-0.767, p = 0.004). Consumption of puffed grains and eggs had an adjusted OR (95%CI) for BLLs ≥20 µg/L of 1.714 (1.012-2.901) (p = 0.045) and 1.787 (1.000-3.192) (p = 0.050), respectively. CONCLUSIONS: BLLs of children in Shenyang are still higher than in developed countries. Consumption of puffed grains and eggs is associated with higher BLLs. Often hand washing before meals may be protective against high BLLs.

Role of piwi-interacting RNA-651 in the carcinogenesis of non-small cell lung cancer.

Piwi-interacting RNAs (piRNAs/piRs) are small non-coding RNAs that can serve important roles in genome stability by silencing transposable genetic elements. piR651, one of these novel piRNAs, regulates a number of biological functions, as well as carcinogenesis. Previous studies have reported that piR651 is overexpressed in human gastric cancer tissues and in several cancer cell lines, including non-small cell lung cancer (NSCLC) cell lines. However, the role of piRNAs in carcinogenesis has not been clearly defined. In the present study, a small interfering RNA inhibitor of piR651 was transfected into the NSCLC A549 and HCC827 cell lines to evaluate the effect of piR651 on cell growth. The association between piR651 expression and apoptosis was evaluated by flow cytometry and western blot analysis. Wound-healing and Transwell migration and invasion assays were used to determine the effect of piR651 on the migration and invasion of NSCLC cell lines. The results revealed that inhibition of piR651 inhibited cell proliferation and significantly increased the apoptotic rate compared with the negative control (NC), as well as altering the expression of apoptosis-associated proteins. There were fewer migrating and invading cells in the piR651-inhibited group than in the NC group in the Transwell assays. Furthermore, in the wound-healing assay, the wound remained wider in the piR651 inhibitor group, suggesting decreased cell migration compared with that in the NC group. The results of the present study demonstrate that piR651 potentially regulates NSCLC tumorigenic behavior by inhibiting cell proliferation, migration and invasion and by inducing apoptosis. Therefore, piR651 is a potential cancer diagnosis marker.

New technique: Development of a large-scale isolation chamber system for the safe and humane care of medium-sized laboratory animals harboring infectious diseases.

The close phylogenetic relationship between humans and non-human primates makes non-human primates an irreplaceable model for the study of human infectious diseases. In this study, we describe the development of a large-scale automatic multi-functional isolation chamber for use with medium-sized laboratory animals carrying infectious diseases. The isolation chamber, including the transfer chain, disinfection chain, negative air pressure isolation system, animal welfare system, and the automated system, is designed to meet all biological safety standards. To create an internal chamber environment that is completely isolated from the exterior, variable frequency drive blowers are used in the air-intake and air-exhaust system, precisely controlling the filtered air flow and providing an air-barrier protection. A double door transfer port is used to transfer material between the interior of the isolation chamber and the outside. A peracetic acid sterilizer and its associated pipeline allow for complete disinfection of the isolation chamber. All of the isolation chamber parameters can be automatically controlled by a programmable computerized menu, allowing for work with different animals in different-sized cages depending on the research project. The large-scale multi-functional isolation chamber provides a useful and safe system for working with infectious medium-sized laboratory animals in high-level bio-safety laboratories.