The prevalent trajectory of early menopause associated with PM exposure across 1956-2018 extrapolated from LightGBM algorithm.

Background: Fine particulate matter (PM) is noxious to female reproductive development and facilitates the occurrence of subsequent diseases. Early menopause is initiative factor of female aging. But due to the lack of historical exposure of PM, we could not gain insight into the linkage between ambient PM exposure and early menopause.

Arsenic exposure is associated with DNA hypermethylation of the tumor suppressor gene p16.

Background: Occupational and environmental exposure to inorganic arsenic leads to development of cancer and represents a significant health hazard in more than 70 countries. The underlying mechanism for arsenic-induced carcinogenesis remains unclear. Laboratory studies suggest that arsenic is a poor mutagen but may cause epigenetic silencing of key tumor suppressor genes such as p16 through DNA hypermethylation.

[Effects of electromagnetic radiation from handsets of cellular telephone on neurobehavioral function].

In order to study the effects of electromagnetic radiation from handsets of cellular telephone on neurobehavioral function, 81 staff with handsets of cellular telephone and 63 staff without handsets of cellular telephone from corporations were selected as the subjects. The subjects were investigated by questionnaire on their general health, lifestyle habit, suppress of spirit, handset using of cellular telephone, environmental exposure, morbidity, and the neurobehavioral core test battery(NCTB). The data was analyzed by chi-square, stepwise regression analysis and covariance statistics.

[Effect of sepia on intracellular Ca2+ concentration, nuclear Ca2+/Mg(2+)-ATPase activities and c-jun expression in H22 cancer cells].

The effect of sepia on the intracellular Ca2+ concentration, nuclear Ca2+/Mg(2+)-ATPase activities and the expression of c-jun were studied in H22 cancer cells by using fluorescent probe and immunohistochemical method. The results showed that intracellular Ca2+ concentration decreased 69% and 79%, nuclear Ca2+/Mg(2+)-ATPase activities diminished 21% and 37%, c-jun expression decreased obviously. The results suggested that sepia probably diminished the intracellular Ca2+ concentration, affected Ca(2+)-dependent nuclear Ca2+/Mg(2+)-ATPase activities, thus reduced the amount of Ca2+ transporting into nuclei, so lessened the promoting effect of Ca2+ on c-jun expression, and therefore inhibited cellular differentiation and proliferation.

[Determination of volatile organic compounds in blood by headspace solid-phase microextraction-gas chromatography].

The headspace solid-phase microextraction (HS-SPME) is a novel extraction technique and has been developed rapidly. It is a fast, simple, solventless and sensitive method for sampling, separating, extracting, injecting and analyzing volatile organic compounds. This paper presents the research work in detecting volatile organic compounds(including ten compounds) in blood.

[Effects of microwave radiation on lipid peroxidation and the content of neurotransmitters in mice].

Male LACA mice were exposed to 900 MHz microwaves at the power densities of 0,1,2 and 5 mW/cm2. The resulting specific absorption rates(SARs) were 0, 0.22, 0.

[Determination of sexual hormones in cosmetics by using Re-HPLC method].

A Re-HPLC method for the determination of seven kinds of sexual hormones, such as estriol in cosmetics was established. Zorbax C18 and Methanol-water were used as solid phase and liquid phase respectively. Methanol was used to extract the hormones in samples using a ultrasonic method.

[Preparation of standard mixture of volatile organic compounds].

This article presented a simple, convenient and flexible device for the preparation of standard mixtures of VOCs. By the aid of a constant pressure on the surface of a liquid with specific composition of VOCs, the liquid passed through a long capillary tube at a definite flow rate. A standard VOCs source was thus formed.

[Effects of cooking oil fume condensate on cellular immunity and immunosurveillance in mice].

Rapeseed oil fume, soyabean oil fume and salad oil fume condensate were injected respectively to female Kunming mice. The results showed that, compared to control group, in mice exposed to low level of rapeseed oil fume condensate, the delayed hypersensitivity responses were inhibited, while in mice exposed to high level of that, the delayed hypersensitivity responses and the NK cells activity were inhibited. In mice exposed to high level of soyabean oil fume condensate the delayed hypersensitivity responses, the NK cells activity and CaM activity were inhibited.

[Study on the existence, distribution and bioaccumulation of chlorophenols in crucian carps].

Four representative chlorophenols (CPs) and their conjugates in fish tissues were determined by gas chromatography with electron capture detector(GC-ECD). Crucian carps were exposed to water contaminated with CPs or not contaminated water separately at room temperature(22 +/- 5 C) for 96 h. If the contaminated water samples are continuously replaced at 24 h interval, the concentration of CPs can be maintained constant throughout the experiment.

Lead can inhibit NMDA-, K(+)-, QA/KA-induced increases in intracellular free Ca2+ in cultured rat hippocampal neurons.

Objective: To examine the effects of Pb2+ on N-methyl-D-aspartate (NMDA)-, K(+)- and quisqualate(QA)/kainite(KA)-induced increases in intracellular free calcium concentration ([Ca2+]i) in cultured fetal rat hippocampal neurons in order to explain the cognitive and learning deficits produced by this heavy metal.

Methods: Laser scanning confocal microscopy was used.

Results: The results clearly demonstrated that adding Pb2+ before or after NMDA/glycine stimulation selectively inhibited the stimulated increases in [Ca2+]i in a concentration-dependent manner.

[Method of separate culture of primary neurons using glial feeder layer].

In order to obtain primarily cultured neurons that can live longer and are healthy, and easy to be isolated and purified, the glial feeder layers are used for culturing the primary neurons separated from the glial cells. The result shows that this method is reliable and easy to be handled. The cultured neurons are pure, and healthy.

[A portable analyzer for determination of iodine in human urine].

A instrument based on principle of ion chromatography and amperometric detector for quick determination of iodine in urine are introduced in this paper, which covers from signal collection and treatment to data analysis. It presents the principle of hardware and software method to obtain the determination by using computer technology as well as the method of analysis of chromatogram. The instrument possess advantage of single, sensitive and simple.

[Combined effect of lead and cadmium on lipid peroxidation in renal tubular epithelial cells of rats].

In order to observe the combined effects of lead and cadmium on lipid peroxidation, the cultured renal tubular epithelial cells (TEC) of rats are used to perform 3 x 3 factorial experimental design. In the experimental group (A-H), rats are given lead and cadmium respectively for 6 hours at different concentrations (A: lead acetate 0.02 mmol/L; B: lead acetate 0.

[Method for multiple gaseous pollutants monitoring by passive sampler].

A new monitoring method used passive samplers by molecular diffusion was developed to determine simultaneously the concentration of HCHO, NO2 and SO2 in the air. Pretreated activated-charcoal fibers were used as absorbent layer. After being sampled, the gaseous pollutants collected in absorbent layer were desorbed by 0.

[Photocatalytic oxidation of airborne VOCs on TiO2].

Titanium dioxide(TiO2) was used to catalyze the photolysis of benzene, xylene, n-heptane, methanol, acetone, ethylether, formaldehyde, trichloroethylene and perchloroethlene in air. The photolysis was carried out with a high pressure mercury lamp. The degradation rate of these VOCs was more than 80 percent in five minuts except formaldehyde.

[Study on dynamic adsorption of HF gas by ion-exchange fiber].

The dynamic adsorption capacity of HF gas utilizing domestic FA-weak basic ion-exchange fiber as adsorbent is studied. Also, the factors influencing dynamic adsorption are investigated and the re-adsorption effect of HF gas is tested. The results showed that the pierce through adsorption amount of HF by ion-exchange fiber is 75 mg/g, and the saturated adsorption amount of HF by the fiber is 152 mg/g.

[Advances on the biological effect indices for fine particles (PM2.5) in air].

Fine particles are complex mixture of air pollutants containing not only a great deal of organic compounds but also varied kind of metals, such as B(a)p, Pb, Cd, Cr etc. Most of those compounds are toxic. Some of them are the cause of lung inflammation and asthma, some are genotoxic with a potential of carcinogenesis.

[Analysis on the dermal irritation caused by imported cosmetics].

Dermal irritation tests on 902 kinds of cosmetics were conducted. The acute dermal irritation/corrosion tests for 175 samples showed no irritation in 65.1% of them, and 34.

[Survey on the microbial pollution of pure water in water dispenser and its disinfection].

The counts of bacteria, total coliforms and fungi of pure water in the water dispensers were detected and the regular pattern of bacterial reproduction in water were studied after the dispensers and water were disinfected. The results showed the bacterial pollution in the water dispensers was serious and the bacteria counts increased with the time of using dispensers lasted. The disinfectant could killed effectively the bacteria in the water sources but it could not control the new bacteria polluted and reproduced while the water dispensers were in use.

[Determination of domoic acid in water and aquatic animals by high performance liquid chromatography].

The content of domoic acid in water and in the body of some aquatic animals was detected by HPLC in order to find out the pollutant condition. The result showed that HPLC analysis was a simple and effective method for determining domoic acid in water and aquatic animals. Domoic acid has been found in some marine shellfish and not in seawater or freshwater.

[Determination of eleven preservatives including bronopol in cosmetic by reversed-phase ion-pair chromatography].

Reversed-phase ion-pair chromatography was used to detect 11 preservatives including bronopol, esters of p-hydroxybenzoic acid (PHBA) in cosmetics. Zorbax C8 column was used and mobile phase was V (0.05 mol/L NaH2PO4):V(methyl alcohol):V(acetonitrile) = 50:35:15 with addition of hexadecyltrimethylammonium chloride (2 mmol/L) and the pH adjusted to 3.

[Determination of dyes in cosmetic by high performance liquid chromatography].

A reversed-phase high performance liquid chromatographic method was used to detect 5 dyes including p-phenylenediamine in cosmetrics. A Zorbax C8 column was used and mobile phase was V (triethanolamine):V(water):V(acetonitrile) = 0.95:94.

[Effects of electromagnetic radiation from cellular telephone handsets on symptoms of neurasthenia].

In order to study the effects of electromagnetic radiation from cellular telephone handsets on symptoms of neurasthenia, 115 and 101 persons with or without handsets were selected. The subjects were investigated by questionnaire on their general health, lifestyle, habit, mental stress, the frequency of using the handsets, living and working environment, the cases of suffered from diseases and symptoms of neurasthenia. The data were analyzed by Chi-square test and Logistic regression statistics.