Role of NF-κB in lead exposure-induced activation of astrocytes based on bioinformatics analysis of hippocampal proteomics.

Lead (Pb), as a heavy metal, is used in batteries, ceramics, paint, pipes, certain ceramics, e-waste recycling, etc. Chronic Pb exposure can result in the inflammation of the central nervous system, as well as neurobehavioral changes. Both glial cells and neurons are involved in central nervous injury following Pb exposure. However, significant cellular events and their key regulators following Pb exposure remain to be elucidated. In this study, rats were randomly exposed to 250 or 500 mg/L PbAc for 9 weeks. Hippocampal proteomics was performed using isobaric tags for relative absolute quantification. Bioinformatics analysis was used to identify 301 and 267 differentially expressed proteins-which were involved in biological processes, including glial cell activation, neural nucleus development, and mRNA processing-in the low and high Pb exposure groups, respectively. Gene Set Enrichment Analysis showed that astrocyte activation was identified as a significant cellular event occurring in the low- or high-dose Pb exposure group. Subsequently, in vivo and in vitro models of Pb exposure were established to confirm astrocyte activation. As a result, glial fibrillary acidic protein expression in astrocytes was much higher in the Pb exposure group. Moreover, the mRNA expression of neurotoxic reactive astrocyte genes was much higher than that of the control group. The analysis of transcription factors indicated that NF-κB was screened as the top transcription factor, which might regulate astrocyte activation following Pb exposure in the rat hippocampus. The data also showed that the inhibition of NF-κB transcription suppressed astrocyte activation following Pb exposure. Overall, astrocyte activation was one of the significant cellular events following Pb exposure in the rat hippocampus, which was regulated by the NF-κB transcription factor, suggesting that inhibiting astrocyte activation may be a potential target for the prevention of Pb neurotoxicity.

The expression of adhesion molecules in Z310 cells induced by combined exposure to black carbon and lead / 中国职业医学

Objective: To investigate the effects of combined exposure to black carbon and lead on the expression of cell adhesion molecules and their regulating microRNAs (miRNAs) in the rat choroid plexus epithelial Z310 cells. Methods: i) Z310 cells were randomly divided into control group, black carbon exposure group, lead exposure group and combined exposure group. The lead exposure group and black carbon exposure group were treated with 10 μmol/L lead acetate and 10 mg/L black carbon, respectively, and the combined exposure group was treated with both in the above doses. After 12.0 hours, the expressions of intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), and mucosal vascular addressin cell adhesion molecule-1 (MAdCAM-1) in Z310 cells was detected by Western blotting. The expression of miR-326, miR-328-3p and miR-542-3p which regulated ICAM-1 was detected by real-time fluorescent quantitative polymerase chain reaction. ii) Z310 cells or Z310 cells transfected with miRNA-326 mimic were randomly divided into control group, miRNA-326 transfection control group, combined exposure group and miRNA-326 transfection combined exposure group. Cells in the two control groups were not treated. The two combined exposure groups were treated with 10 mg/L black carbon and 10 μmol/L lead acetate for 12.0 hours. The expression of ICAM-1 was detected by Western blotting. Results: i) The relative expression of ICAM-1, VCAM-1 and MAdCAM-1 in the cells of black carbon exposure group and ICAM-1 in the lead exposure group was higher than those in the control group (all P<0.05). The relative expression of ICAM-1 and MAdCAM-1 in the combined exposure group was higher than those in the other three groups (all P<0.05). The relative expression of VCAM-1 in cells of combined exposure group was higher than those in the control group and lead exposed group (all P<0.05). The relative expression of miR-326 in cells of the lead exposure group and black carbon exposure group was lower than those in the control group (all P<0.05). The relative expression of miR-326 in the combined exposure group was lower than that in the other three groups (all P<0.05). There was no significant difference between miR-328-3p and miR-542-3p in the four groups (all P>0.05). ii) The relative expression of ICAM-1 in cells of the miR-326 transfection control group cells was lower than that in the control group (P<0.05), while in the cells in the combined exposure and miRNA-326 transfection combined exposure group, it was higher than that in the control and miRNA-326 transfection control groups (all P<0.05), and lower in the miRNA-326 transfection combined exposure group than in the combined exposure group (P<0.05). Conclusion: Black carbon or lead exposure can upregulate the expression of ICAM-1, VCAM-1 and MAdCAM-1 in Z310 cells. Black carbon and lead combined exposure lead to a synergistic effect on upregulation of ICAM-1 and MAdCAM-1 expression, particularly ICAM-1. The combined exposure of black carbon and lead may upregulate the expression of ICAM-1 by downregulating the expression of miR-326.

Impact of lead oxide nanoparticle exposure on the polarization of microglia cells in mouse hippocampus / 中国职业医学

Objective To investigate the effect of exposure to lead oxide nanoparticles (PbO NPs) on the polarization of microglia in mouse hippocampus. Methods i) Specific pathogen-free male C57 mice were randomly divided into control group, low-, medium- and high-dose groups, with 10 mice in each group. Mice in these three dose groups were intraperitoneally injected with PbO NPs suspension at doses of 5, 10 and 20 mg/kg per day, respectively, and mice in the control group were intraperitoneally injected with the same volume of 0.9% sodium chloride solution, five days per week for four weeks. ii) BV-2 cells were treated with PbO NPs at doses of 0.0, 2.5, 5.0 and 10.0 mg/L for 24 hours. iii) BV-2 cells were randomly divided into control group, PbO NPs group and triggering receptor expressed on myeloid cells 2 (TREM2) high expression + PbO NPs group. The cells in the control group received no treatment. The cells in PbO NPs group were exposed to 10.0 mg/L PbO NPs suspension for 24 hours. Cells in TREM2 high expression + PbO NPs group were transfected with Trem2 high expression plasmid, and then exposed to 10.0 mg/L PbO NPs suspension for 24 hours. iv) The mRNA expression of M1 markers ［nitric oxide synthase (iNos), cyclooxygenase 2 (Cox2), chemokine receptor 7 (Ccr7)］, M2 markers ［arginin-1 (Arg-1), transforming growth factor-β (Tgf-β), chemokine receptor 2 (Ccr2)］ and Trem2 of microglia was detected by real-time fluorescent quantitative polymerase chain reaction. The protein expression of iNOS, ARG-1 and TREM2 was detected by Western blotting. Results i) During the experiment, there was no significant difference in body weight of mice among these four groups (P>0.05). The relative expression of Cox2 and Ccr7 mRNA in the hippocampus of the mice increased in the low-dose group and the iNos, Cox2 and Ccr7 mRNA increased in the medium- and high-dose groups, compared with the control group (all P<0.05). The relative mRNA expression of Tgf-β in the hippocampus of the mice of low-dose group and Arg-1, Tgf-β and Ccr2 in the medium- and high-dose groups was decreased compared with the control group (all P<0.05). The mRNA relative expression of iNos, Cox2 and Ccr7 was increased (all P<0.05), while the mRNA relative expression of Arg-1, Tgf-β and Ccr2 was decreased (all P<0.05) in the hippocampus of the mice of high-dose group compared with the low-dose group. The relative expression of Trem2 mRNA and TREM2 protein in the hippocampus of mice of the medium- and high-dose groups was lower than those in the control group (all P<0.05). The relative expression of Trem2 mRNA and TREM2 protein in the hippocampus of mice of the high dose group was lower than those in the low- and the medium-dose groups (all P<0.05). With the increase of PbO NPs exposure dose, the relative expression of iNOS protein in hippocampus tissues of mice increased (P<0.01), and the relative expression of ARG-1 protein decreased (P<0.01). ii) With the increase of PbO NPs exposure dose, the relative expression of iNOS protein increased (P<0.01), and the relative expression of ARG-1 protein decreased (P<0.01) in BV-2 cells. The relative expression of iNOS protein in BV-2 cells of PbO NPs group and TREM2 high expression + PbO NPs group was increased (all P<0.05), and the relative expression of ARG-1 protein decreased (all P<0.05) compared with the control group. The relative expression of iNOS protein decreased (P<0.05), and the relative expression of ARG-1 protein increased (P<0.05) in BV-2 cells of TREM2 high expression + PbO NPs group compared with the PbO NPs group. Conclusion Exposure to PbO NPs could increase the M1 polarization and decrease the M2 polarization of microglia, with a dose-effect relationship. The M1 polarization of microglia decreased and M2 polarization increased after overexpression of Trem2 gene. The regulation of microglia polarization by TREM2 may be involved in the neurotoxic effects of PbO NPs.

Effects of nano lead oxide exposure on cognitive function and inflammatory mechanism of leukocyte infiltration in mice / 中华行为医学与脑科学杂志

Objective:To investigate the effect of nano lead oxide (nano-PbO) exposure on learning and memory as well as spatial exploration ability in the mice, and the role of leukocyte infiltration of brain tissue in neurobehavioral damage caused by nano-PbO exposure.Methods:A total of 60 male SPF grade Kunming mice were divided into control group, low-dose nano-PbO group, medium-dose nano-PbO group and high-dose nano-PbO group according to body mass matching method, with 15 mice in each group.Mice in low, medium and high dose groups of nano-PbO were intraperitoneally injected with 5 mg·kg -1, 10 mg·kg -1, 20 mg·kg -1 nano-PbO, respectively. And mice in the control group were intraperitoneally injected with the same volume of 0.9% normal saline.The frequency of intervention was once a day for 28 days.Morris water maze test and open field test were used to detect the ability of learning and memory and spatial exploration of mice. Western blot was used to detect the protein expression of tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β) in hippocampus of mice, intercellular cell adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1) in mouse microvessels and lymphocyte function-associated antigen-1 (LAF-1) in mouse blood leukocyte. The proportion of leukocytes in mouse brain was detected by flow cytometry. All statistical analyses were performed by SPSS 20.0. Morris water maze data were analyzed by repeated measures ANOVA, the other data among multiple groups were compared by one-way ANOVA, and Tukey's test was used for further pairwise comparison.Pearson correlation analysis was performed to evaluate the correlation between neurobehavioral indexes and the proportion of white blood cells, TNF-α and IL-1β in brain tissue. Results:Morris water maze results showed that the escape latency of the four groups of mice had a significant interaction between group and time( F=3.21, P<0.05). The escape latencies of mice in middle and high dose groups of nano-PbO were higher than that in the control group (both P<0.05), and the numbers of crossing the platform of the two groups were lower than that in the control group (both P<0.05). The results of open field test showed that there was a statistically significant difference in the residence time of the mice in the four groups ( F=119.10, P<0.01). The total standing times of mice in the middle group and high dose group of nano-PbO were lower than that in the control group (both P<0.01). The results of Western blot showed that the levels of TNF-α and IL-1β in hippocampus tissue of mice were significant differences among the four groups ( F=7.21, 9.89, both P<0.05). The levels of TNF-α and IL-1β in the hippocampus of mice in the high-dose nano-PbO group were higher than those in the control group (TNF-α: (0.35±0.10), (1.03±0.30), P<0.05; IL-1β: (0.32±0.10), (0.50±0.15), P<0.05). The results of flow cytometry analysis showed that the proportions of leukocytes in the brain tissue of mice in the low, medium and high dose groups of nano-PbO were (9.99±1.09)%, (13.03±0.94)% and (16.51±3.89)%, respectively. Among them, the proportions of leukocytes in the middle and high dose groups of nano-PbO were significantly higher than that in the control group((8.13±1.29)%) (both P<0.05). The results of correlation analysis showed that the proportion of leukocytes, levels of TNF-α, IL-1β protein of hippocampus in the medium, high dose groups of nano-PbO were negatively correlated with the behavioral indexes ( r=-0.815, -0.744, -0.578, all P<0.01; r=-0.771, -0.836, -0.704, all P<0.05; r=-0.823, -0.876, -0.695, all P<0.05). The results of Western blot showed that the levels of ICAM-1 and VCAM-1 in cerebral microvessels of mice in the four groups were significantly different ( F=5.51, 16.19, both P<0.05). The levels of ICAM-1 and VCAM-1 in the middle and high dose groups of nano-PbO were higher than those in the control group(ICAM-1: (1.07±0.16), (1.21±0.35), (0.59±0.19), all P<0.05; VCAM-1: (0.68±0.12), (1.92±0.23), (0.23±0.05), both P<0.05). In addition, there was a significant difference in the level of LFA-1 protein in blood leukocytes of mice in the four groups ( F=41.80, P<0.05). The levels of LFA-1 in the middle and high dose groups of nano-PbO were higher than that in the control group((0.33±0.06), (0.89±0.23), (0.05±0.01), both P<0.05). Conclusion:The nano-PbO exposure can lead to cognitive impairment and increased inflammatory factors in the hippocampus of mice, which may be related to the increase of ICAM-1 and VCAM-1 in vascular endothelial cells, which promotes leukocyte infiltration into brain tissue.

Mechanisms of ferroptosis in microglial cell line BV-2 cells after lead acetate exposure / 环境与职业医学

Background Lead exposure induces microglial cell death, of which the mechanism is unclear. Ferroptosis is a new death form and its role in microglia death has not been reported. Objective To investigate the role of ferroptosis in microglia following lead exposure in order to provide a theoretical basis for the mechanism of lead neurotoxicity. Methods Microglial cell line BV-2 cells were co-cultured with 0, 10, 20 and 40 μmol·L−1 lead acetate for 24 h. The 40 μmol·L−1 lead acetate group with iron chelator (DFO) was named the 40+DFO group. Changes in BV-2 cell morphology after lead exposure were observed under an inverted microscope; tissue iron kit and glutathione kit were used to detect intracellular iron and glutathione (GSH) respectively; flow cytometry was applied to detect lipid reactive oxygen species (lipid ROS) immunofluorescence intensity. Western blotting and qPCR were adopted to detect the expressions of glutathione peroxidase 4 (GPX4), solute carrier family 7 member 11 (SLC7A11), transferrin receptor 1 (TFR-1), divalent metal transporter 1 (DMT1), ferroportin 1 (FPN1) protein and mRNA. Results Compared with the control group, the number of BV-2 cells decreased with increasing doses of lead and the cells showed a large, round amoeboid shape. The intracellular levels of iron of BV-2 cells were (1.08±0.04), (1.29±0.03), and (1.72±0.10) mg·g−1 (calculated by protein, thereafter) in the 10, 20, and 40 μmol·L−1 lead acetate groups, respectively, significantly higher than that in the control group (P<0.05), and the intracellular level of iron in the 40+DFO group, (1.34±0.10) mg·g−1, was lower than that in the 40 μmol·L−1 lead acetate group, (1.72±0.03) mg·g−1 (P<0.05). Compared with the control group, the TFR-1 and DMT1 protein and mRNA expressions were increased in BV-2 cells in the 10, 20, 40 μmol·L−1 lead acetate groups (P<0.05), especially in the 40 μmol·L−1 lead acetate group; the FPN1 protein expression did not change significantly, but the FPN1 mRNA expressions in BV-2 cells in the 10, 20, 40 μmol·L−1 lead acetate groups were significantly decreased (P<0.05). Compared with the control group, the intracellular GSH level decreased and the lipid ROS content increased in all three lead acetate groups; compared with the 40 μmol·L−1 lead acetate group, the GSH level increased by 12.30% and the lipid ROS content decreased by 13.00% in the 40+DFO group (P<0.05). The expressions of GPX4 protein were reduced to 50.00%, 35.00%, and 17.00% of that of the control group in the 10, 20, and 40 μmol·L−1 lead acetate groups respectively, while the expressions of GPX4 mRNA were also significantly reduced; the expressions of SLC7A11 protein and mRNA in the 20 and 40 μmol·L−1 lead acetate groups were lower than that in the control group, with the most significant decrease in the 40 μmol·L−1 lead acetate group (P<0.05). Conclusion Lead exposure could induce ferroptosis in BV-2 cells, in which iron transport imbalance and oxidative damage might be involved.

Research on Early Warning Mechanism and Model of Liver Cancer Rehabilitation Based on CS-SVM.

Since the 20th century, cancer has become one of the main diseases threatening human health. Liver cancer is a malignant tumor with extremely high clinical morbidity and fatality rate and easy recurrence after surgery. Research on the postoperative recurrence time and recurrence location of patients with liver cancer has a crucial influence on the postoperative intervention of patients. Evaluation of the clinical manifestations of patients after liver cancer surgery is conducted according to medical knowledge or national standards to determine the main factors affecting liver cancer rehabilitation. In order to better study the mechanism of liver cancer recurrence, this paper uses CS-SVM to predict the recurrence time of liver cancer patients, so as to timely intervene the patients. There are five evaluation indicators which are basic indicators, immune indicators, microenvironment indicators, psychological indicators, and nutritional indicators, respectively. This paper collects the clinical evaluation data of postoperative follow-up visits for patients with liver cancer in a hospital, improves the parameter selection process of the support vector machine by using the search ability of the cuckoo algorithm, and establishes an algorithm-optimized prediction model of support vector machine for the prognosis of liver cancer to predict the location and approximate time of recurrence. According to the clinical evaluation data of patients with liver cancer after surgery, logistics regression, BP neural network, and other related methods are used to predict the prognosis of liver cancer patients after surgery. The prediction effects of several methods are compared, and the superiority of the model is discussed. At the end of this article, we conducted an empirical analysis on the clinical evaluation data of patients with liver cancer after surgery. For the collected samples of 776 liver cancer recurrences after surgery, the established liver cancer prognosis outcome prediction model was used to predict the recurrence time and recurrence location, respectively. The mean square error of recurrence time prediction is 9.2101, which is much smaller than the prediction mean square error of BP neural network of 177.9451; the prediction accuracy of recurrence location is 95.7%, which is much higher than the 63.14% of logistic regression. The empirical analysis results show that the improved support vector machine model based on cuckoo established in this paper can effectively predict the time and location of cancer recurrence.

Isolation and Identification of a Murine Norovirus Persistent Infection Strain in China.

Murine Norovirus (MNV) is one of the most known viruses among viruses in mice. Because of the high prevalence of MNV in frequently used laboratory animals in biomedical researches, there is a significant impact of MNV. There may be different prevalence degrees and molecular characteristics of MNV in different regions around the world. Here, we reported an MNV strain "designated HBTS-1806" isolation from commercial mice's feces that caused a detectable cytopathic effect (CPE) in RAW264.7 cells. According to electron microscopy, the virus was 50-70 nm in diameter. The complete genome of HBTS-1806 is 7383 nucleotides with a structure similar to that of MNV reference strains. According to phylogenetic analysis on the basis of the whole genome, HBTS-1806 shared nucleotide sequence identities of 90.2-95.4% with other Chinese isolates reported. Analysis of amino acid sequence on the basis of ORF1 and ORF2 suggested that the isolated strain may be derived from recombination. Although no gross lesions or histopathological changes were found from mice infected with 5 × 105 TCLD50 of MNV by oral gavage inoculation, the intestinal virus loads lasted 12 weeks, suggesting a persistent infection strain of MNV isolate in China.

Effect of lead exposure on neuroinflammation of hippocampus and cognitive impairment in diabetic rats / 中国职业医学

OBJECTIVE: To explore the effects of lead exposure on inflammatory damage of hippocampus and cognitive impairment in diabetic rats. METHODS: The specific pathogen free(SPF) male healthy Wistar rats were randomly divided into control group and lead-exposed group. The SPF male Goto-Kakisaki Wistar rats rats were randomly divided into diabetes group and diabetes lead-exposed group, with 10 rats in each group. Rats in lead-exposed group and diabetes lead-exposed group were continuously exposed to lead acetate water with a mass fraction of 0.025% for 9 weeks. Rats in control group and diabetes group were given distilled water. The body weight and blood glucose level of rats were measured before lead exposure and at 1, 3, 5, 7 and 9 weeks after exposure. After the exposure, Morris water maze test was used to evaluate the learning and memory ability of rats. The lead levels in whole blood and hippocampal tissues were detected by inductively coupled plasma mass spectrometry, and the expression of mRNA and protein expression of inflammatory factors in hippocampal tissues of rats were detected by real-time fluorescence quantitative polymerase chain reaction and enzyme-linked immunoadsorption, respectively. RESULTS: At the end of lead exposure, the difference of body mass of rats in the diabetes group and the diabetes lead-exposed group was not statistically significant compared with that in the same group before exposure(all P values were >0.05); but the body mass of rats in these two groups was lower than that of the control group and the lead-exposure group(all P values were <0.05). The blood glucose levels of rats were higher in the diabetic group and the diabetes lead-exposed group than that in the control group and the lead-exposed group, respectively(all P values were <0.05). Morris water maze test showed that the escape latency of rats in the 1 st, 2 nd and 3 rd day were longer in diabetes group and the diabetes lead-exposed group than that in the control group and the lead-exposed group(all P values were <0.05). The number of times of crossing platforms were less in the lead-exposed group and the diabetes group than that of the control group(all P values were <0.05). The number of times of crossing platforms was more in the diabetes lead-exposed group than that in the other 3 groups(all P values were <0.05). The levels of lead in blood and hippocampus of rats were higher in the lead-exposed group than those in the control group(all P values were <0.05), and those in the diabetes lead-exposed group were higher than that in the other 3 groups(all P values were <0.05). The relative expression of mRNA of interferon-γ(ifn-γ) and interleukin(il)-6 in hippocampal tissues of rats was higher in the lead-exposed group and the diabetes group than that of the control group(all P values were <0.05). The relative expression of mRNA of tumour necrosis factor-α(tnf-α) and il-1β in the hippocampal tissues of rats was higher in the diabetes group than that of the control group and the lead-exposed group, respectively(all P values were <0.05). The relative expression of mRNA of ifn-γ, tnf-α, il-1β and il-6 in hippocampal tissues of rats was higher in the diabetes lead-exposed group than that of the other 3 groups(all P values were <0.05). The relative protein expression of IFN-γ, TNF-α, IL-4 and IL-6 in hippocampal tissues of rats was higher in lead-exposed group than that of the control group(all P values were <0.05). The relative protein expression of IFN-γ, TNF-α, IL-1β and IL-6 in hippocampal tissues of rats was higher in diabetes group than that of the control group(all P values were <0.05). The relative protein expression of IFN-γ, IL-1β and IL-6 in hippocampal tissues of rats was higher in diabetes group than that of the other 3 groups(all P values were <0.05). CONCLUSION: Diabetes can promote the lead accumulation in the blood and hippocampus of rats. The combined effect of lead exposure and diabetes can up-regulate the expression of pro-inflammatory cytokines in the hippocampal tissues of rats, aggravate the inflammatory response, and have a synergistic effect on the cognitive impairment in rats.

Factors related to antibiotic-associated diarrhea in patients in the intensive care unit receiving antifungals: a single-center retrospective study.

OBJECTIVE: To analyze factors related to antibiotic-associated diarrhea (AAD) in patients in the intensive care unit (ICU) receiving antifungals with the aim of informing rational antibiotic use. METHODS: Sex, age, medical history, use of proton pump inhibitors, administration of parenteral nutrition, albumin level, occurrence of AAD, type of antibiotics, duration of ICU admission, and prognosis were retrospectively analyzed. The associations of age, sex, medical history, and other factors with AAD were associated by logistic regression. RESULTS: In total, 284 patients were enrolled (antifungals, n = 110; no antifungals, n = 174). The total incidence of AAD was 32.39%. The incidence of AAD was significantly different between the groups (52.73% vs. 19.54%). The duration of proton pump inhibitor therapy, duration of antifungal therapy, enzyme inhibitor antibiotic use, and azithromycin use were associated with AAD in ICU patients receiving antifungal therapy. The mean duration of ICU admission was higher in patients receiving antifungal therapy (20.14 ± 11.50 vs. 14.48 ± 8.54 days). There was no significant difference in ICU mortality rates. CONCLUSION: The duration of proton pump inhibitor therapy, duration of antifungal therapy, use of enzyme inhibitor antibiotics, and use of azithromycins were associated with AAD in ICU patients receiving antifungal therapy.

Effect of lead exposure on the accumulation of copper and iron in central nervous system of rats / 中华劳动卫生职业病杂志

Objective@#To investigate the dynamic changes of copper and iron contents in brain tissue, body fluids and barriers of rats exposed to lead at different periods in order to provide a theoretical basis for the study of the mechanism of lead nerve injury.@*Methods@#Sixty-four healthy adult SPF male SD rats were randomly divided into control group and lead exposure group, after one week of adaptive feeding, rats in the lead exposure group were treated with 250 mg/L lead acetate, and rats in control group were treated with ordinary drinking water, the experimental period was 12 weeks. After exposure for 3, 6, 9 and 12 weeks, the samples including blood, choroid plexus, cerebrospinal fluid, cortex, hippocampus, striatum, hypothalamus, amygdala, substantia nigra and cerebellum were obtained. Lead, copper and iron content in all kinds of samples were detected by Inductively Coupled Plasma Mass Spectrometry(ICP-MS). The measurement data were presented as Mean±SD, Comparison of metal contents in different tissues of rats at different time analyzed using repeated measurement analysis of variance, Two-variable correlation analysis using Spearman correlation test.The relationship between lead exposure experiod and copper and iron in samples was studied by using trend test.@*Results@#After 12 weeks of lead exposure compared with the control group, lead contents in cortex, hippocampus, striatum, hypothalamus, amygdala, substantia nigra and cerebellum of rats were 2.21, 2.44, 2.95, 3.53, 4.01, 1.85 and 2.86 folds of control group, and the differences were statistically significant(P<0.05). At the same time, lead content in blood, cerebrospinal fluid,choroid plexus, brain microvessels and bones increased. The increase rate in the amygdala and cerebrospinal fluid ranked first among brain tissue or barrier,which were 4.01 and 3.0 folds respectively. Compared with the control group, Compared with the control group, copper content in cortex,hippocampus, striatum, hypothalamus,amygdala, cerebellum,blood,cerebrospinal fluid,choroid plexus and cerebral microvasculature showed an increasing trend among rats following 3,6,9,12 weeks of lead exposure. Copper content change in the striatum was highest among all brain tissue. The increase rate of copper content in the striatum was at the top among brain tissues. After 12 weeks of lead exposure,copper content in brain microvessels was 4.98 folds higher than that of the control group (P<0.05). After lead exposure at different periods,the iron content in the cortex, hippocampus, striatum,cerebrospinal fluid,choroid plexus and brain microvessels of experimental rats all increased(P<0.05). And the iron increase rate in the hypothalamus or cerebrospinal fluid increase ranked first among brain tissues or body fluid the most obviously.@*Conclusion@#With the increase of exposure time, lead exposure can changes in the contents of copper and iron in different brain tissues,body fluids and barriers in rats,among which, the contents of copper and iron in the amygdala,cerebrospinal fluid and brain microvessels increase significantly. This may be related to nerve damage from lead exposure.

Lead exposure promotes hypothalamic inflammation in mice on a high-fat diet / 中国职业医学

OBJECTIVE: To investigate the effect and mechanism of lead exposure on hypothalamic inflammatory factors in mice fed with high-fat diet. METHODS: Specific pathogen free healthy male Kunming mice were randomly divided into control group, high-fat diet group, lead exposure group, and combined exposure group, with 8 rats in each group. The control group and the lead exposure group were given regular diet, while high-fat diet group and combined exposure group were given high-fat diet. The lead exposure group and combined exposure group were given water with 250 mg/L lead acetate. The control group and high-fat diet group were given double distilled water. Continuous lead exposure was given for 9 weeks, 7 days per week. Body weights of the mice were measured every other week. After 9 weeks of exposure, the behavioral changes of mice were detected by open field test. The levels of triglyceride(TG), low density lipoprotein(LDL) and high density lipoprotein(HDL) in serum were detected by microplate reader. Western blotting was used to detect the relative protein expression of interleukin(IL)-1β, IL-6, IL-17 A, IL-22, tumor necrosis factor-α(TNF-α) and transforming growth factor-β(TGF-β) in the hypothalamus of mice. The relative expression of mRNA of IL-1β, IL-6, IL-17 A and TNF-α mRNA was detected by real-time fluorescence quantitative polymerase chain reaction. RESULTS: Beginning from the first week, the body weights of mice in the high-fat diet group and the combined exposure group were higher than that in the control group and the lead exposure group(P<0.05). The numbers of standing in the lead exposure group and the combined exposure group were lower than that in the control group and the high-fat diet group(P<0.05). The distances of central area activity in the high-fat diet group, the lead exposure group and the combined exposure group were lower than that in the control group(P<0.05). The total distances in the high-fat diet group and the combined exposure group were lower than that in the control group(P<0.05). The serum levels of TG and LDL in the combined exposure group increased(P<0.05), and the HDL level decreased(P<0.05), when compared with the control group and the lead exposure group. The relative protein expression of IL-1β, IL-6, IL-17 A and IL-22 in the hypothalamus of the high-fat diet group and lead exposure group was higher than those of the control group(P<0.05). The relative protein expression of TNF-α and TGF-β in the hypothalamus of the lead exposure group was higher than that in the control group(P<0.05). The relative protein expression of IL-1β, IL-6, IL-17 A, TGF-β in the hypothalamus of the combined exposure group was higher than the other 3 groups(P<0.05). The relative protein expression of IL-22 in the hypothalamus of the combined exposure group was higher than that of the control group(P<0.05), while the relative protein expression of TNF-α was higher than that of the control group and the high-fat diet group(P<0.05). The relative expression of IL-1β, IL-6, IL-17 A, and TNF-α mRNA in the hypothalamus of the high-fat diet group, the lead exposure group and the combined exposure group was higher than that in the control group(P<0.05). The above indicators of mice in the lead exposure group were higher than that in the high-fat diet group(P<0.05). The above indicators of mice in the combined exposure group were higher than those in the high-fat diet group and the lead exposure group(P<0.05). CONCLUSION: Lead exposure can promote neurobehavioral changes and hypothalamic inflammatory damage in high-fat diet mice. IL-1β, IL-6, IL-17 A, TGF-β and TNF-α might involve in the process of synergistic effect of lead and high-fat diet exposure on inflammatory hypothalamic injury.

Effects of lead exposure and high fat diet on the hippocampal inflammatory factors and learning-memory in male rats / 中国职业医学

OBJECTIVE: To investigate the effects of lead exposure and high fat diet on the hippocampal inflammatory factors and learning-memory in rats. METHODS: A total of 40 specific pathogen free male SD rats were randomly divided into control group,high fat diet group,lead exposure group,combine exposure group,10 rats in each group. Rats in control group were given regular diet and rats in high-fat diet group were given high-fat diet. Rats in lead exposure group were given regular diet and water with 400 mg/L lead acetate. Rats in combine exposure group were given high fat diet and water with 400 mg/L lead acetate. Body weight was measured every other week. The exposure period was 9 weeks. Morris water maze was applied to measure the learning-memory. The content of total cholesterol,triglyceride(TG),low density lipoprotein cholesterol(LDL) and high density lipoprotein cholesterol(HDL) in serum were detected by using microplate reader. The lead content of hippocampus was detected by inductively coupled plasma mass spectrometer. Enzyme-linked immuno sorbent assay was used to detect the content of tumor necrosis factor-α(TNF-α),interleukin(IL)-1β,IL-4,IL-6 and interferon-γ(IFN-γ). RESULTS: Beginning from the third week,the body weight of rats in high fat diet and combine exposure group were significantly higher than that in control group(P < 0. 05). In addition,the body weight of rats in combine exposure group were higher than that in lead exposure group(P < 0. 05). Escape latency and the frequency of crossing platform of rats in high fat diet group,lead exposure group and combine exposure group were significant changed compared with those in control group(P < 0. 05). The escape latency of rats in combine exposure group increased compared with those in high fat diet group and lead exposure group(P < 0. 05). In addition,serum TG and LDL content in high-fat diet group and combine exposure group increased and HDL decreased compared with the control exposure group and lead exposure group(P < 0. 05). Compared with the control group and high fat diet group,the content of lead in hippocampus of lead exposure group and combine exposure group substantially increased(P < 0. 05). The levels of TNF-γ,IL-6,IL-1β,IFN-γ of hippocampus in high fat diet group,lead exposure group and combine exposure group were significantly higher than those in control group(P < 0. 05). Besides,the levels of IL-4 of hippocampus in lead exposure group and combine exposure group were higher than that in control group(P < 0. 05). IL-1β content of rats hippocampus in combine exposure group was higher than that in high-fat diet group or lead exposure group(P < 0. 05). CONCLUSION: Combine lead and high-fat diet exposure can exert a synergy in decrease of learning-memory in rats. IL-1β might involved in the process of synergic neurotoxicity induced by lead and high fat diet.

Effects of low temperature adjustable sodium dialysis combined astragalus injection in patients with chronic cardiac insufficiency uremia combined the clinical curative effect of dialysis related hypotension / 重庆医学

Objective To investigate the effects of low temperature adjustable sodium dialysis combined Astragalus injection in patients with chronic cardiac insufficiency uremia combined the clinical curative effect of dialysis related hypotension .Methods Fourty‐nine patients with uremia combined chronic cardiac insufficiency and suffered repeated dialysis hypotension were involved in this study ,and they were divided into treatment group(n=25) and control group(n=24) .Patients in the control group were treated with hemodialysis for low temperature (35 .5 ℃) ,and sodium curve dialysis ;patients in the treatment group were treated with the same method in that of control group ,and they were treated with astragalus injection 40 mL continuous intravenous drip .Then ob‐serve the blood pressure changes and treatment effect of the two groups of before and after treatment .Results Systolic pressure of the treatment group and the control group was (92 .6 ± 8 .4) and (89 .5 ± 9 .0) mm Hg ,and that of after treatment was (99 .9 ± 8 .0) and (94 .9 ± 9 .3) mm Hg respectively ,the difference before and after treatment in each group was significant (t=3 .147 , 2 .044 ,P<0 .05) ,and the difference of systolic pressure before and after treatment in each group was significant (t=2 .020 ,P<0 .05) .Before the treatment ,the left ventricular ejection fraction score of treatment group and control group was (45 .80 ± 3 .62)%and (46 .01 ± 3 .59)% ,and that of after treatment was (59 .05 ± 3 .15)% and (53 .85 ± 1 .60)% ,respectively ,and the difference be‐fore and after treatment was significant (t=13 .906 ,9 .847 ,P<0 .05) ,and the difference of the left ventricular ejection fraction score after treatment in the two groups was significant (t=7 .328 ,P<0 .05) .Conclusion For patients with uremia combined chronic car‐diac insufficiency and suffered repeated dialysis hypotension ,low temperature adjustable sodium dialysis can significantly reduce the incidence of hypotension in the process of dialysis .But combined huangqi injection in the treatment group could significantly in‐creased the left ventricular ejection fraction ,thus improve the left ventricular function in patients with dialysis .

Gas chromatography for determination of N-isopropylaniline in workplace atmosphere / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To establish a method for determination of N-isopropylaniline in the workplace atmosphere by gas chromatography.</p><p><b>METHODS</b>Air samples were collected by silica gel tube and desorbed by acetone. Then they were separated through DB-WAX columns and N-isopropylaniline was determined by flame ionization detector.</p><p><b>RESULTS</b>The concentration of N-isopropylaniline showed a good linear relationship within the range of 1.40∼665.0 µg/ml. The sampling efficiency was 100%. The accuracy was 96%∼ 99% and the precision was 2.1%∼7.0%. The minimum detectable concentration was 0.056 mg/m(3) (with sampled air volume of 7.5 L).</p><p><b>CONCLUSION</b>The method meets the requirements of analysis and applies to the determination of N-isopropylaniline in the workplace atmosphere.</p>

Application of error-correction education mode for diabetic dietary education in the nursing specialist outpatient service / 中国实用护理杂志

Objective To explore the best mode of diabetic dietary education in the nursing specialist outpatient service,which is suit for China's national situation.Methods A total of 100 diabetic patients consulting diabetes diet in the nursing specialist outpatient service were divided into observation group and control group with 50 cases each by random digits table method.The routine sermonic education mode was used in control group,while the error-correction education mode was used in observation group.The question-real-time evaluation was performed at the end of the education and a follow-up evaluation after 6 months of intervention was evaluated.Results Grasp of the knowledge of diabetes diet in observation group immediately after education and 6 months after education were better than those in control group,t=3.07,3.06,P＜0.01.In the follow-up evaluation after 6 months of intervention,fasting blood glucose and glycosylated hemoglobin were (6.84±0.79) mmol/L,(6.83±0.36) ％ in observation group and (7.56±0.93) mmol/L,(7.67±0.87) ％ in control group.The indices in observation group were significantly better than those in control group,t=-4.17,-6.32,P＜0.01.Conclusions Using the error-correction education mode can correct the false dietary behavior of patients and improve the effect of the diabetic dietary education more effectively.

Effects of nano-lead exposure on learning and memory as well as iron homeostasis in brain of offspring rats / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To investigate the effects of nano-lead exposure on learning and memory and iron homeostasis in the brain of the offspring rats on postnatal day 21 (PND21) and postnatal day 42 (PND42).</p><p><b>METHODS</b>Twenty adult pregnant female Sprague-Dawley rats were randomly divided into control group and nano-lead group. Rats in the nano-lead group were orally administrated 10 mg/kg nano-lead, while rats in the control group were administrated an equal volume of normal saline until PND21. On PND21, the offspring rats were weaned and given the same treatment as the pregnant rats until 42 days after birth. The learning and memory ability of offspring rats on PND21 and PND42 was evaluated by Morris water maze test. The hippocampus and cortex s amples of offspring rats on PND21 and PND42 were collected to determine iron and lead levels in the hippocampus and cortex by inductively coupled plasma-mass spectrometry. The distributions of iron in the hippocampus and cortex were observed by Perl's iron staining. The expression levels of ferritin, ferroportin 1 (FPN1), hephaestin (HP), and ceruloplasmin (CP) were measured by enzyme-linked immunosorbent assay.</p><p><b>RESULTS</b>After nano-lead exposure, the iron content in the cortex of offspring rats on PND21 and PND42 in the nano-lead group was significantly higher than those in the control group (32.63 ± 6.03 µg/g vs 27.04 ± 5.82 µg/g, P<0.05; 46.20 ±10.60 µg/g vs 36.61 ± 10.2µg/g, P<0.05). The iron content in the hippocampus of offspring rats on PND42 in the nano-lead group was significantly higher than that in the control group (56.9 ± 4.37µg/g vs 37.71 ± 6.92µg/g, P<0.05). The Perl's staining showed massive iron deposition in the cortex and hippocampus in the nano-lead group. FPNl level in the cotfex of offspring rats on PND21 in the nano-lead group was significantly lower than that in the control group (3.64 ± 0.23 ng/g vs 4.99 ± 0.95 ng/g, P<0.05). FPN1 level in the hippocampus of offspring rats on PND42 in the nano-lead group was significantly lower than that in the control group (2.28 ± 0.51 ng/g vs 3.69 ± 0.69 ng/g, P<0.05). The escape latencies of offspring rats on PND21 and PND42 in the nano-lead group were longer than those in the control group (15.54 ± 2.89 s vs 9.01 ± 4.66 s; 6.16 ± 1.42 s vs 4.26 ± 1.51 s). The numbers of platform crossings of offspring rats on PND21 and PND42 in the nano- lead group were significantly lower than those in the control group (7.77 ± 2.16 times vs 11.2 ± 1.61 times, P<0.05; 8.12 ± 1.51 times vs 13.0 ± 2.21 times, P<0.05).</p><p><b>ONCLUSION</b>n Nano-lead exposure can result in iron homeostasis disorders in the hippocampus and cortex of offspring rats and affect their learning and memory ability.</p>

Myelin protein zero and its antibody in serum as biomarkers of n-hexane-induced peripheral neuropathy and neurotoxicity effects / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Chronic exposure to n-hexane can lead to peripheral neuropathy that no effective treatment regimen could be applied presently. This study investigated whether myelin protein zero (P0) protein and its antibody could be used to distinguish n-hexane intoxication and protect workers from peripheral neuropathy.</p><p><b>METHODS</b>We compared P0 protein and its antibody among three levels of n-hexane-exposed groups, which included 18 patients with n-hexane-induced peripheral neuropathy as case group, 120 n-hexane-exposed workers as n-hexaneexposed control group, and 147 non-hexane-exposed participants used as control group. ELISA method was applied to detect P0 protein and its antibody.</p><p><b>RESULTS</b>P0 protein in serum was significantly higher in the case group and n-hexane-exposed control group in comparison with the control group (P < 0.01). Compared with the n-hexane-exposed control group, the case group also had significant increase of P0 protein (P < 0.01). After 6 months therapy, P0 protein was observed to decrease significantly in the case group (P < 0.01). The P0 antibody in serum was significantly higher in the n-hexane-exposed control group than in the control group (P < 0.01), but not significantly different between cases and controls.</p><p><b>CONCLUSIONS</b>P0 antibodies in serum may be a short-term effect biomarker for n-hexane exposure. P0 protein in serum may be an early effective biomarker for peripheral nerve neuropathy and its biological limit value needs investigation in the future study.</p>

Effect of lead exposure on permeability,secretion and transportation function of blood-cerebro-spinal fluid barrier of rats / 中国药理学与毒理学杂志

OBJECTIVE To investigate the effects of lead exposure on the permeability,secretion and transportation function of blood-cerebro-spinal fluid barrier (BCB)of rats in order to provide the theo-rical basis for elucidating the mechanis m of lead induced neurotoxicity.MEHTODS 60 SPF SD rats were rando mly divided into 4 groups,including a control group and three doses lead exposed groups. Rat in the lead exposure groups were given drinking water containning 0.05%,0.1 % and 0.2% lead acetate (at dose of 80,160,320 mg·kg -1 )for 8 weeks.Laser scanning confocal microscopy was uti-lized to determine the lead content in seru m,cerebrospinal fluid (CSF)and choroid plexus sa mples. Morris maze was used to test learning and me mory.Fe moral artery perfusion of Evans blue (EB)and fluorescein sodiu m (NaFI)was performed to measure BCB permeability function.Confocal laser scan-ning was applied to detect junction adhesion molecule (JAM)and occludin protein expression in choroid plexus.ELISA was used to measure the concentration of transthyretin (TTR)and leptin in seru m and CSF.RESULTS The lead content in seru m,choroid plexus and CSF significantly increased,especially the lead level in CSF.Morris water maze data showed that escape latency of rat in lead acetate 160 and 320 mg·kg -1 group were 52 ±12,(89 ±19)s,respectively,longer than that of control group 〔(28 ±7)s, P<0.05〕.The ti mes across platform of rats in lead acetate 160 and 320 mg·kg -1 group were lower than that of control group(P <0.05).The NaFI content in CSF of rats in all lead acetate exposure groups were 0.94 ±0.09,1 .02 ±0.03 and (1 .08 ±0.18)mg·L -1 ,respectively,and were higher than those of control group〔(0.74 ±0.04)mg·L -1 〕;While the EB content in CSF of rat in lead acetate 160 and 320 mg·kg -1 group were higher than the control group(P <0.05),which indicated that lead acetate exposure at low dose can lead to the increase of permeability of BCB.Laser scanning confocal micro-scope i mages showed that the JAM protein expression of choroid plexus in lead acetate 160 and 320 mg·kg -1 group were 44.9% and 42.9% of the control group.Sa me decline was seen in terms of occludin expression.The TTR content of CSF of rats in lead acetate 80 mg·kg -1 group was (32.3 ± 1 1 .7)ng·g -1 protein,lower than that of the control group,and the difference was significant.This decline was also noted in lead acetate 160 and 320 mg·kg -1 group.The data of TTR in CSF suggested that the low dose lead acetate exposure can disrupt the BCB secretion function.The leptin levels in CSF of lead acetate 160 and 320 mg·kg -1 group were lower than that in the control group (P <0.05 ). CONCLUSION Lead exposure did disrupt the permeability,transportation and secretion function of BCB.Our data suggest that BCB dysfunction might be involved in the mechanis m of lead induced neurotoxicity.

Effects of lead exposure on copper and copper transporters in choroid plexus of rats / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To investigate the effects of lead exposure on the copper concentration in the brain and serum and the expression of copper transporters in the choroid plexus among rats.</p><p><b>METHODS</b>Sixty specific pathogen-free Sprague-Dawley rats were randomly divided into a control group and three lead-exposed groups, with 8 mice in each group. The lead-exposed groups were orally administrated with 500 (low-dose group)), 1 000 (middle-dose group), and 2 000 mg/L (high-dose group) lead acetate in drinking water for eight weeks. And the rats in control group were given 2 000 mg/L sodium acetate in drinking water. The content of lead and copper in the serum, hippocampus, cortex, choroid plexus, bones, and cerebrospinal fluid (CSF) was determined by inductively coupled plasma-mass spectrometry (ICP-MS). Confocal and real-time PCR methods were applied to measure the expression of copper transporters including copper transporter 1 (Ctr1), antioxidant protein 1 (ATX1), and Cu ATPase (ATP7A).</p><p><b>RESULTS</b>Compared with the control group, the lead-exposed groups showed significantly higher lead concentrations in the serum, cortex, hippocampus, choroid plexus, CSF, and bones (P < 0.05) and significantly higher copper concentrations in the CSF, choroid plexus, serum, and hippocampus (P < 0.05). Confocal images showed that Ctr1 protein was expressed in the cytoplasm and cell membrane of choroid plexus in control group. However, Ctr1 migrated to CSF surface microvilli after lead exposure. Ctr1 fluorescence intensity gradually increased with increasing dose of lead, except that the middle-dose group had a higher Ctr1 fluorescence intensity than the high-dose group. In addition, the middle- and high-dose groups showed a lower ATX1 fluorescence intensity compared with the control group. Real-time PCR data indicated that the three lead-exposed groups showed significantly higher mRNA levels of Ctr1 and ATP7A compared with the control group (P < 0.05).</p><p><b>CONCLUSION</b>Copper homeostasis in the choroid plexus is affected by lead exposure to induce copper homeostasis disorders in brain tissue, which may be one of the mechanisms of lead neurotoxicity.</p>

Multiple-Factor Analysis on Air Pollution, Part of Immune and Pulmonary Ventilation Function in Children / 环境与健康杂志

ve To explore the health impacts of air pollution on children. Methods Based on monitoring data on outdoor air pollutants of SO2, NOx, TSP and CO, The local non-specific immune function [the activity of saliva lysozyme, the content of secretory immunoglobulin A (SIgA)]and the pulmonary ventilation function [vital ca-pacity (VC), forced vital capacity (FVC), forced expiratory volume in one second (FEV1), 25%, 50% and 75% forced expiratory volume in one second (V25, V50, V75) and maximum ventilatory volume (MVV)] were determined, and the questionaire was carried out among 656 school-age children aged 7~15 yrs in industrial area (polluted area)and 712 school-age children aged 7~15 yrs in relative clean area (control area). Results Significantly higher levels of SO2, NOx , TSP in outdoor air were found in polluted area compared with those in control area ( P