The differential expression of Stathmin in the spinal cord tissue of hens exposed to tri-o-cresyl phosphate / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To screen the differently expressed proteins related to regulating the depolymerization of microtubules in the spinal cord of hens exposed to tri-o-cresyl phosphate (TOCP) and to provide target protein evidence for exploring the mechanisms of the delayed neurotoxicology (OPIDN) induced by organophosphorus compounds (OPs).</p><p><b>METHODS</b>Forty two Roman hens were randomly divided into three groups, i.e. TOCP group treated with 1000 mg/kg TOCP; intervention group treated with 40 mg/kg phenylmethanesulfonyl fluoride (PMSF) before 1000 mg/kg TOCP treatment and control group treated with tap water. Four hens in each group were sacrificed on the 5th and 20th days after exposure, respectively. Spinal cords were separated and homogenates at low temperature, and the total proteins were extracted. The OPIDN symptoms observed and recorded in the remaining 6 hens in each group. The differently expressed proteins related to regulating the depolymerization of microtubules were screen by two-dimensional electrophoresis and mass spectroscopy (MS).</p><p><b>RESULTS</b>The OPIDN symptoms appeared on the 5th day after exposure in TOCP group, which were gradually serious with time. The results by two-dimensional electrophoresis and MS showed that the Stathmin expression was downregulated 3.4 times and 2.8 times in TOCP group, respectively, as compared with the control and PMSF intervention groups. However, there was no significant difference of the Stathmin expression between control group and PMSF intervention group.</p><p><b>CONCLUSION</b>The Stathmin expression in the spinal cord tissues of hens exposed to TOCP significantly downregulated. Moreover, the downregulated Stathmin expression may be related to excess polymerization of microtubules and the mechanism of OPIDN.</p>

Screening the proteins of organophosphoms ester-induced delayed neurotoxicity in the cerebral tissue of hens exposed to tri-ortho-cresyl phosphate / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To screen the proteins with differential expression levels in the cerebral tissue of hens exposed to tri-ortho-cresyl phosphate (TOCP), and to provide target proteins for studying the mechanism of organophosphoms ester-induced delayed neurotoxicity (OPIDN).</p><p><b>METHODS</b>Thirty two adult Roman hens were randomly divided into four groups: TOCP group was exposed to 1000 mg/kg TOCP, PMSF group was exposed to 40 mg/kg PMSF, PMSF plus TOCP group was exposed to 40 mg/kg PMSF and after 24 h exposed to 1000 mg/kg TOCP, control group was exposed to normal saline. All hens exposed to chemicals by gastro-intestine for 5 days were sacrificed, and the cerebral tissue were dissected and homogenized in ice bath. Total proteins extracted from the cerebral tissue were separated by isoelectric focusing as the first dimension and SDS-PAGE as the second dimension. The 2-DE maps were visualized after silver staining and analyzed by Image Master 2D software. At last ,the expressed protein spots were identified by Mass spectrometry.</p><p><b>RESULTS</b>From total proteins in TOCP group, the PMSF plus TOCP group and PMSF group, 1185, 1294 and 1063 spots were detected, respectively. One thousand three hundred thirty two spots from total proteins in control group were detected. The match rates of protein spots in TOCP group, the PMSF plus TOCP group and PMSF group were 78.32 %, 79.56 % and 80.93%, respectively. There were 235 protein spots with differential expression levels between TOCP group and control group, which included 158 up regulation spots and 77 down regulation spots. According to the PMSF features, there were 102 spots with differential expression levels between TOCP group and control group and without differential expression levels between TOCP group and PMSF plus TOCP group, among them there were 13 spots with 4 fold differential expression levels between TOCP group and control group and without differential expression levels between TOCP group and PMSF group. Seven protein spots (homer-1b, Destrin, heat shock protein 70, eukaryotic translation initiation factors, proteasome alpha1 subunit, lactate dehydrogenase B, glutamine synthetase) were detected by Mass spectrometry.</p><p><b>CONCLUSION</b>There are 112 protein spots with differential expression levels of the cerebral tissue in TOCP group, which may be related to OPIDN, among them 13 protein spots with differential expression levels are associated closely with OPIDN. Seven protein spots detected by Mass spectrometry may be related to the mechanism induced by OPIDN.</p>

Maternal and fetal exposure to four carcinogenic environmental metals / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To examine maternal and fetal exposure levels to four carcinogenic metals, arsenic (As), cadmium (Cd), nickel (Ni), and beryllium (Be), and to investigate their environmental influences.</p><p><b>METHODS</b>Metal concentrations in maternal and umbilical cord blood were measured by inductively coupled plasma-mass spectrometry (ICP-MS). Environmental factors that might play a role in exposure were analyzed using Mann-Whitney nonparametric U-tests and multiple linear regression.</p><p><b>RESULTS</b>The concentrations of As, Cd, and Ni in umbilical cord blood (5.41, 0.87, and 139.54 μg/L) were significantly lower than those in maternal blood (6.91, 1.93, and 165.93 μg/L). There were significant positive correlations between the maternal and cord concentrations of each carcinogen. Our results showed that: (i) exposures to potentially harmful occupational factors during pregnancy were associated with high levels of maternal As, Cd, and Ni; (ii) living close to major transportation routes (<500 m) or exposure to second-hand smoke during pregnancy increased the maternal Cd levels and (iii) living close to industrial chimneys induced high maternal Ni levels. Multiple linear regression analysis showed that these environmental factors remained significant in models of the influences of these four carcinogens.</p><p><b>CONCLUSION</b>Both mothers and fetuses had been exposed to As, Cd, Ni, and Be. The increased levels of these carcinogens in pregnant women were associated with some detrimental environmental factors, such as occupational exposure, contact with second-hand smoke and living close to major transportation routes or industrial chimneys.</p>

Effects of sodium arsenite on catalase in human keratinocytes / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To evaluate the effects of sodium arsenite on the activity, the mRNA and the protein expression of CAT in human keratinocyte cell line (HaCaT).</p><p><b>METHODS</b>The activity of catalase (CAT) was detected by ultraviolet direct velocity assay. RT-PCR was used to detect the mRNA expression of CAT and Western blotting was conducted to detect the protein expression of CAT.</p><p><b>RESULTS</b>If the cells were treated with higher than 5.0 micromol/L sodium arsenite, the activity, mRNA and protein expression of CAT were decreased significantly and in a dosage dependent fashion (P < 0.05).</p><p><b>CONCLUSION</b>CAT is inhibited by sodium arsenite in the transcription, translation and activity levels.</p>