Screening key factors from bone marrow mesenchymal stem cells for alleviating silicosis in mice / 中国职业医学

OBJECTIVE: To explore the mechanism of bone marrow mesenchymal stem cells(BMSCs) in alleviating silica-induced lung injury in mice. METHODS: Ten specific pathogen free healthy male C57 BL/6 mice were selected for isolating BMSCs and bone marrow macrophages(BMDMs). Transwell chamber was used, BMDMs were inoculated onto the upper chamber and BMSCs in the lower chamber. We divided them into sequencing control group and silica(SiO_2) exposure group. All cells were pre-stimulated with 50 μg/L mass concentration lipopolysaccharide for 4 hours. In the SiO_(2 ) group, 250 mg/L mass concentration SiO_2 was added to the upper chamber of transwell and cultured for 16 hours. Total RNA was extracted from the BMSCs collected from the lower chamber. HiSeq/MiSeq high-throughput sequencing technology was used to detect the BMSCs RNA paired-end sequencing. Transcriptome sequencing data was obtained and bioinformatics analysis was performed. Another 12 specific pathogen free healthy male C57 BL/6 mice were randomly divided into control group and experimental group. All mice received one intra-tracheal injection of 20.0 μL(250 g/L mass concentration) of silica dust suspension. After 6 hours, the mice in the control group was given 500.0 μL of 0.9% sodium chloride solution and mice in the experimental group was given 500.0 μL of BMSCs suspension(cell density 1×10~9/L) by tail vein infusion.Mice were sacrificed 12 hours later. The relative mRNA expression of interleukin(IL)-1 Ra, IL-10, tumor necrosis factor stimulating gene 6(TSG-6) and prostaglandin E2(PGE2) in lung tissues of mice were measured by quantitative real-time PCR(q-PCR). Meanwhile, BMDMs and BMSCs transwell co-culture models were established. The cells were divided into 5 groups: BMSCs group, BMSCs+BMDMs group, BMSCs+BMDMs+ lipopolysaccharide(LPS) group, 50 mg/L SiO_2 group, and 100 mg/L SiO_2 group. After 16 hours of corresponding SiO_2 stimulation, BMSCs of each group were collected and the relative mRNA expression levels of IL-1 Ra, IL-10, TSG-6, and PGE2 in the cells were detected by q-PCR. RESULTS: Compared with sequencing control group, BMSCs co-cultured with SiO_2 had 19 genes up-regulated and 21 genes down-regulated, including 10 genes up-regulated for more than 2.0-fold. The relative mRNA expression of IL-1 Ra, IL-10, PGE2 and TSG-6 in the lung tissue of mice increased in the experimental group than that of the control group(all P<0.05). The relative mRNA expression of TSG-6 increased by 37.5 times higher than that of the control group. Compared with the BMSCs+BMDM+LPS group, the level of TSG-6 mRNA relative expression increased in both the 50 mg/L SiO_2 group and the 100 mg/L SiO_2 group(all P<0.05). CONCLUSION: TSG-6 could be the key factor of BMSCs that can attenuate silica-induced lung injury.

Neurotoxicity and hematotoxicity of maternal exposure to 1-bromopropane in male offspring rats / 中国职业医学

OBJECTIVE: To observe the neurotoxicity and hematotoxicity of maternal exposure to 1-bromopropane(1-BP) on the offspring rats by the breast-feeding route. Method A total of eight specific pathogen free female rats and their 64 male newborn rats were divided into the control group and the exposure group, with four lactation female rats and their 32 male newborn rats in each group. The female rats in exposure group were intragastrically administered with 700.00 mg/kg body mass of 1-BP during lactation, and the control group was given equal volume of corn oil for 21 days, once a day. The body mass of female rats and their offspring rats were measured during the exposure period. After exposure, the Morris water maze and the open field tests were performed in male offspring. The blood samples of offspring were collected for blood routine and blood biochemical indexes detection. The histopathological examination was performed in the hippocampus in the male offspring. RESULTS: A litter of eight pups in the exposure group began to die one day after the mother rat was exposed to 1-BP, and all rats died on the ninth day after exposure. There was no significant difference in the body mass of female rats between the exposure group and the control group(P>0.05). The body mass of offspring rats in the exposure group was lower than that in the control group at the same time point from the first day to the 21 st day of the female rats exposed to 1-BP(all P<0.05). In the orientation navigation experiment, the escape latency time on the first, the second day and the total distance on the first day in the offspring of the exposure group were significantly prolonged than those in the control group at the same time points(all P<0.05). The number of times of crossing the platform of offspring rats in the exposure group was less than that in the control group in the spatial exploration test(P<0.01). In the open field test, there was not statistical significance of the activity, rest time ratio, total distance, the distance ratio and time ratio in the central region in the offspring between the two groups(all P>0.05). The counts of white blood cells, neutrophils, lymphocytes, and average red blood cell width, platelet ratio and average platelet volume of the offspring of the exposure group decreased(all P<0.05), the serum levels of globulin, total protein, triacylglycerol and total bilirubin decreased(all P<0.05), and the albumin/globulin ratio and serum glucose level increased(all P<0.05), when compared with that of the control group. Histopathological examination results showed that the nerve fibers were loose in the hippocampal dentate gyrus area, and there were necrotic neurons and loss of nerve fibers in the CA1 area of the offspring rats. CONCLUSION: Maternal exposure to 1-BP during lactation can induce neurotoxicity and hematotoxicity to offspring rats. The neurotoxicity mainly caused damage to the central nerve system, which affected the learning and memory function of the offspring rats. The reason may be related to the damage caused by 1-BP on the hippocampal function.

Study on the laboratory historical control values of biological indicators in SD rats with 28-day repeated dose oral toxicity tests / 中国职业医学

OBJECTIVE: To establish the laboratory historical control values for biological indicators in SD rats with 28-day repeated dose oral toxicity tests. METHODS: The body mass, blood routine indexes, serum biochemical indexes, organ mass and organ coefficient of 10 batches of specific pathogen free SD rats in the control group and the control additional group were collected for 28-day repeated dose oral toxicity tests, and the historical control values was established. RESULTS: The body mass of both male and female SD rats increased with the increasing age(all P<0.01). The body mass of male rats was higher than that of female rats each week(all P<0.01). The body mass, blood routine and serum biochemical indexes, organ mass and organ coefficient of SD rats were affected by the age and gender of rats to varying degrees. The effects of age and gender on organ mass and organ coefficient were not consistent. The laboratory historical control values of body mass, blood routine indexes, serum biochemical indexes, organ mass and organ coefficient of SD rats were established according to the age measured in weeks and the gender of rats. CONCLUSION: The laboratory control values of biological indicators of SD rats should be established according to different weekly age and the gender of rats. Organ coefficient is more suitable as an observation index for toxicological safety evaluation compared with organ mass.

Influencing factors of hyperuricemia in male workers of a petrochemical enterprise / 中国职业医学

OBJECTIVE: To analyze the prevalence and risk factors of hyperuricemia in male workers in a petrochemical enterprise. METHODS: A total of 1 604 male workers in a petrochemical production enterprise was selected as the study subjects using judgment sampling method. The living habits and health status of the workers were investigated, and the related examination results of hyperuricemia were collected through the “Occupational Health Surveillance and Monitoring Information System” independently developed by Guangdong Province Hospital for Occupational Disease Prevention and Treatment, and the influencing factors were analyzed. RESULTS: The prevalence of hyperuricemia in male workers was 29.6%(474/1 604). Multivariate Logistic regression analysis showed that high diastolic blood pressure, high triglyceride(TG), overweight and obesity were risk factors for hyperuricemia in male workers after excluding age, smoking and other confounding factors(all P<0.01). The results of restricted cubic spline model showed that there was a linear dose-response relationship between hyperuricemia and body mass index and diastolic blood pressure( χ~2=36.19 and 21.46, all P<0.01), and a non-linear dose-response relationship between hyperuricemia and TG( χ~2=14.56, P<0.01). CONCLUSION: The risk factors for hyperuricemia among male workers in the petrochemical enterprise included elevated diastolic blood pressure, elevated TG, overweight and obesity, and there was a dose-response relationship.

Inhibition of macrophage signaling pathway by bone marrow mesenchymal stem cells (BMSC) and alleviation of pulmonary alveolitis in mice exposed to silica dust / 上海预防医学

Objective To study the mechanism of bone marrow mesenchymal stem cell (BMSC)-mediated alleviation of pulmonary alveolitis in mice exposed to silica dust. Methods Thirty mice were randomly divided into 3 groups:control group, and two silica groups with or without BMSCs transplantation.Through the tracheal tube clearance, mice in control group received a single injection 20.0 μL of 0.90% sodium chloride solution by one time.Mice from in silica group and silica/BMSCs transplantation group first received a single injection of 20.0 μL silica dust suspension (mass concentration 250 g/L); followed by either 500.0 μL of 0.90% sodium chloride solution or by 500.0 μL of BMSCs suspension (cell density 1×109/L) through tail vein infusion 6 hours later.Mice were euthanized on the 3th day of the experiments.The levels of NALP3 inflammasome in lungs was determined by Western blot.Transwell system was used for co-culture of BMDM (in upper-chamber) and BMSC (in lower-chamber) co-culture.The level of cytokines IL-1β in BMDM cultural supernatant was detected by enzyme linked immunosorbent assay after stimulated by SiO2 stimulation.The levels of NALP3 inflammasome of in BMDM was determined by Western blot. Results The levels of pro-IL-1β, IL-1β, pro-caspase-1, caspase-1 in lungs of silica/BMSCs transplantation group were lower than that in silica group (P < 0.01).In the experiment in vitro, the concentrations of IL-1β in SiO2 exposed BMSC/BMDM co-culture group were lower than the SiO2 exposure only groups (P < 0.05).Meanwhile, the levels of pro-IL-1β, IL-1β, pro-caspase-1, caspase-1 in BMDM was lower than that in silica group (P < 0.01).The level of these proteins didn′t change while when the cell-free supernatant of BMSC culture was directly added. Conclusion The BMSC could inhibit NALP3 inflammasome of macrophages stimulated by SiO2.

Comparative study on 5-bromo-2-fluorobenzonitrile in rat and human plasma protein binding and its metabolism in liver microsomes in vitro / 中国职业医学

OBJECTIVE: To study the metabolic characteristics of 5-bromo-2-fluorobenzonitrile in vitro and compare the differences between rats and human,and for the purpose of providing data for poison effect research and extrapolating poison effect of 5-bromo-2-fluorobenzonitrile from animals to human being. METHODS: Equilibrium dialysis method was used to analyze the protein binding ratio of 5-bromo-2-fluorobenzonitrile in the plasma of rats and humans in the groups of low dose,medium dose and high dose which were treated with mass concentration of 5-bromo-2-fluorobenzonitrile at 500,5 000 and 50 000 μg / L respectively. Metabolic incubation systems of SD rat microsomes and human liver microsomes were established in vitro. When the mass concentration of 5-bromo-2-fluorobenzonitrile in the systems was 800 μg / L,the concentration of liver microsome was 0. 5 g / L; after being incubated for 0,10,30,60 and 90 min with the involvement of the regeneration system of nicotinamide-adenine dinucleotide phosphate in the incubation systems,the metabolic reaction was stoped. The residual amounts of 5-bromo-2-fluorobenzonitrile were analyzed and metabolic half-life of 5-bromo-2-fluorobenzonitrile incubating with liver microsomes in vitro was figured out. RESULTS: Protein binding ratio of 5-bromo-2-fluorobenzonitrile in the groups of low dose,medium dose and high dose were( 83. 5 ± 0. 9) %,( 88. 8 ± 0. 3) % and( 88. 6 ± 0. 3) % in rats plasma,and( 85. 2 ± 0. 1) %,( 89. 0 ± 0. 1) % and( 91. 1 ± 0. 4) % in human plasma. Both in rat plasma and human plasma,the protein binding ratio of 5-bromo-2-fluorobenzonitrile in the groups of medium dose and high dose were significantly increased than that in the low-dose group( P < 0. 01). In human plasma,the protein binding ratio of 5-bromo-2-fluorobenzonitrile in the high-dose group significantly increased than that in the medium-dose group( P < 0. 01). In the groups of low dose and high dose,the protein binding ratio of 5-bromo-2-fluorobenzonitrile in human plasma significantly increased than that in rats plasma( P < 0. 01). Absolute differences in protein binding ratio of 5-bromo-2-fluorobenzonitrile between the rat plasma and the human plasma were no more than 2. 5% in the same dose groups. Metabolic half-life of 5-bromo-2-fluorobenzonitrile incubating with rats and human liver microsomes and control solution in vitro were respectively( 58. 6 ± 1. 6),( 59. 2 ± 1. 5) and( 65. 0 ± 6. 3) min,which shows no significant differences( P < 0. 05). CONCLUSION: The potein binding ratio and metabolism of 5-bromo-2-fluorobenzonitrile in liver microsomes in rat plasma is similar to those in human plasma. Both in the plasmas of rats and humans,5-bromo-2-fluorobenzonitrile has high protein binding ratio,and 5-bromo-2-fluorobenzonitrile is not metabolized in liver microsomes of either rats or humans.

Mechanism of 1,2-dichloroethane-induced toxicity in SH-SY5Y Cells / 中国职业医学

OBJECTIVE: To establish the cell model of human neuroblastoma cell( SH-SY5Y cell) exposed to1,2-dichloroethane( 1,2-DCE) in vitro and to explore the mechanism of 1,2-DCE-induced toxicity in SH-SY5Y cells.METHODS: SH-SY5Y cells were collected in their logarithmic growth phase and cultured in complete medium that had final concentrations of 1,2-DCE in 0,10,20,30,40,50,60,70 and 80 mmol / L for 24 hours. Cell morphology was observed and cell survival rate was examined by CCK-8 assay. Using chemical colorimetric method, the activity of lactic dehydrogenase( LDH) in the cell culture supernatant,and the intracellular level of malondialdehyde( MDA),the intracellular activities of superoxide dismutase( SOD) and adenosine triphosphate( ATP) enzymes were detected. RESULTS: With the increasing exposure concentrations of 1,2-DCE,the cell density of SH-SY5Y cells gradually decreased,the synapse became shorter,the membrane ruptured,cytoplasm condensed and cytoplasmic contents overflowed increased.With the increasing concentration of 1,2-DCE,the cell survival rate decreased( P < 0. 01),the activity of LDH in the cell culture supernatant increased( P < 0. 01). These changes had a dose-effect correlation. Intracellular MDA level,and activities of SOD,Na~+-K~+-ATP enzyme,Ca~(2+)-Mg~(2+)-ATP enzyme and total ATP enzyme increased at first and then decreased. The activity of LDH in the cell culture supernatant and cell survival rate was negatively correlated( the correlation coefficient is- 0. 907,P < 0. 01). CONCLUSION: 1,2-DCE could inhibit the proliferation of SH-SY5Y cells.The mechanism may be related to the permeability change of cell membrane,cellular damage from excessive free radicals,the decrease of free radical scavenging capacity,ATP enzyme activity and calcium overloading. SH-SY5Y cells can be used as a common cell line for 1,2-DCE cytotoxicity analysis.

Immune cytotoxic effect of trichloroethylene in Jurkat T cells / 中国职业医学

OBJECTIVE: To explore the immune cytotoxic effect and the maximum non-effect dose of trichloroethylene( TCE) on Jurkat T cells in vitro. METHODS: i) Naive and activated Jurkat T cells were treated with different concentrations of TCE( 0. 10, 0. 50, 1. 00, 2. 00, 5. 00, 10. 00 mmol / L). Phorbol-12-myristate-13-acetate and ionomycin were used as agonist. No TCE was used in the control group and dimethyl sulfoxide( DMSO) was used as the solvent group. The morphology of Jurkat T cells was observed using a light microscope and the survival rate of Jurkat T cells was investigated using CCK-8 essay after cells were cultured for 24,48 and 72 hours. ii) Nave and activated Jurkat T cells were treated with different concentrations of TCE( 0. 00,0. 02,0. 20,2. 00 mmol / L). The apoptosis of cells was detected using flow cytometry and the level of interleukin-2( IL-2) in supernatant was detected using enzyme linked immunosorbent assay after cells were cultured for 24,48 and 72 hours. RESULTS: i) Cytotoxic effect was observed after cells were exposed to 10. 00 mmol / L TCE for 24 hours. Cells dispersed,cell volume diminished,cell membrane ruptured,cytoplasm condensed and increased outflow of intercellular organelles. The effect of interaction between exposure dose and exposure time was statistically significant on cell survival rate( P < 0. 01). Compared with the control and DMSO groups at the same time points,there were no significant differences in the 0. 10,0. 50,1. 00 and 2. 00 mmol / L TCE treatment groups in cell survival rates in three different time points( P > 0. 05),while the cell survival rates of 5. 00 and 10. 00 mmol / L TCE treatment groups were significantly decreased( P < 0. 01). ii) When TCE concentration was 0. 00-2. 00 mmol / L,there were no significant differences in the main effect of exposure dose and interactions of between exposure dose and cell type or exposure time on cell apoptosis rate( P > 0. 05). Compared with the same time points and groups of naive Jurkat T cells,the levels of IL-2 of activated Jurkat T cells were significantly increased( P < 0. 01). In the three different time points,the level of IL-2 of activated Jurkat T cells increased in accordance with the TCE exposure dose,showing a dose-effect relationship( P < 0. 01). The level of IL-2 of activated Jurkat T cells increased in accordance with TCE exposure time,showing a time-effect relationship( P < 0. 01). CONCLUSION:s TCE at the level of 2. 00 mmol / L had no observed effect in Jurkat T cells. High doses of TCE( ≥5. 00 mmol / L) showed cytotoxic damages to naive and activated Jurkat T cells and low doses of TCE( ≤2. 00 mmol / L) could stimulate activated Jurkat T cells secrete IL-2 in a dosedependent and time-dependent manner.

Mechanism of bone marrow mesenchymal stem cells in alleviating pulmonary alveolitis in mice exposed to silica dust / 中国职业医学

OBJECTIVE: To explore the mechanism of bone marrow mesenchymal stem cells( BMSCs) in alleviating pulmonary alveolitis in mice exposed to silica dust. METHODS: Five specific pathogen free healthy male C57 BL /6 mice were used to isolate BMSCs using bone marrow adherent method. The poly-potent differentiation ability of BMSCs were identified by 3 differentiation-inducing experiments. Forty-five mice of similar background were randomly divided into 3groups: control group,silica group and BMSCs transplantation group. The mice of the control group were given 20. 0 μL of0. 90% sodium chloride solution by one time intratracheal injection. The mice of silica group and BMSCs transplantation group were first received 20. 0 μL( 250 g / L mass concentration) of silica dust suspension by one time intratracheal injection; followed by 500. 0 μL of 0. 90% sodium chloride solution or 500. 0 μL of BMSCs suspension( cell density 1 ×109/ L) by tail vein infusion 6 hours later. Mice were euthanized on the 3rd day of the experiment. Lung functional coefficient and pathologic changes in the lung were examined. The level of cytokines in bronchoalveolar lavage fluid( BALF) was detected by enzyme linked immunosorbent assay. Wright-Giemsa staining was used for staining cells in BALF for counting. Flow cytometry( FCM) was used to measure the percentage of macrophages of BALF in the mice. RESULTS: BMSCs were successfully induced to differentiate into osteogenic,adipogenic and chondrogenic cells and developed into osteoblast,adipogenic cells and chondroblast. On the 3rd day of the experiment,the mice in silica group showed histopathological changes similar to pulmonary alveolitis; while there was no obvious inflammatory change observed in the BMSCs transplantation group,and the structure of lung tissue appeared normal. The lung coefficient of the silica group was higher than that of the control group( P < 0. 05); the lung coefficient of BMSCs transplantation group was lower than that of the silica group( P < 0. 05),but it showed no significant difference when compared to the control group( P > 0. 05). The interleukin( IL)-1β,IL-6 and chemokine ligand 3 levels in BALF in the silica group were higher than those of the control group( P < 0. 05),and the above 3 indices in the BMSCs transplantation group regaining the level of the control group( P > 0. 05) were lower than those of the silica group( P < 0. 05). The level of tumor necrosis factor-α in BALF in silica group and BMSCs transplantation group were higher than that of the control group( P < 0. 05),but there was no significant difference between silica group and BMSCs transplantation group( P > 0. 05). The level of IL-10 in BALF showed no significant difference in these 3 groups( P > 0. 05). Wright-Giemsa staining results showed that the number of total cells and macrophages in BALF in the silica group was higher than that of the control group( P < 0. 05),and the above cell number of BMSCs transplantation was lower than that of silica group( P < 0. 05),but it showed no significant difference when compared to the control group( P > 0. 05). The FCM result showed that the percentage of macrophages was in accordance with that of the Wright-Giemsa staining. CONCLUSION: The BMSCs can alleviate pulmonary alveolitis in the mice exposed to silica dust by inhibiting the amounts and activity of alveolar macrophages and down-regulating the expression of IL-1β and IL-6 in BALF.

Effect of 1-bromopropane inhalation on the expression of neuron specific enolase and myelin basic protein in plasma and brain tissue of male rats / 中国职业医学

OBJECTIVE: To determine the effects of 1-bromopropane( 1-BP) subacute inhalation on the expression of neuron specific enolase( NSE) and myelin basic protein( MBP) in plasma and brain tissue in male rats. METHODS: Specific pathogen free adult male Wistar rats were randomly divided into 4 groups with 12 rats in each group: the control group,the low-,medium- and high-dose groups with 1-BP exposure levels at 0,1 250,2 500 and 5 000 mg / m3,respectively. The rats were given continuous dynamic inhalation of 1-BP for 6 hours per day,5 days per week,for continuous 4 weeks. The rats were sacrificed at the end of exposure,9 rats from each group were randomly chosen and the blood from abdominal aorta was collected and the plasma was isolated. The plasma levels of NSE and MBP were measured by enzyme-linked immunosorbent assay. The whole brain,pallium,cerebellum and brainstem were isolated for detection of organ coefficient.The rest of 3 rats in each group were processed for histopathologic examination and the expressions of NSE and MBP were evaluated by immunohistochemistry. RESULTS: The organ coefficients of whole brain,pallium,cerebellum and brainstem in the high-dose group were higher than those in the control group [( 0. 754 ± 0. 056) % vs( 0. 663 ± 0. 035) %,( 0. 382 ±0. 037) % vs( 0. 339 ± 0. 021) %,( 0. 115 ± 0. 008) % vs( 0. 098 ± 0. 006) % and( 0. 213 ± 0. 018) % vs( 0. 183 ±0. 014) %,respectively,P < 0. 01]. The plasma NSE levels in the 3 exposure groups were lower than those of control group [( 7. 92 ± 0. 53) vs( 24. 73 ± 11. 44),( 9. 12 ± 2. 17) vs( 24. 73 ± 11. 44) and( 11. 10 ± 2. 84) vs( 24. 73 ±11. 44) mg / L,respectively,P < 0. 01]. The plasma MBP levels in all groups showed no statistical difference [( 2. 52 ±0. 70) vs( 2. 50 ± 0. 72) vs( 2. 47 ± 0. 66) vs( 2. 44 ± 0. 81) mg / L,P > 0. 05]. Histopathological examination showed that a few necrotic nerve cells were observed in hippocampus of rats in high-dose group. The expressions of NSE and MBP in brain tissue of rats in control,low- and medium-dose groups showed no significant difference. The down-regulated expression of NSE and MBP were only observed in cells of hippocampus of rats in the high-dose group. CONCLUSION: The1-BP induced neural toxicity was reflected in the function of central nervous system rather than in the structural morphology. The plasma NSE might be one of the effect biomarkers for monitoring 1-BP exposure.

Effects of subacute 1-bromopropane inhalation on the expression of SYP,GluR2 and NR2B in hippocampus of male rats / 中国职业医学

OBJECTIVE: To study the potential effects of subacute 1-bromopropane( 1-BP) inhalation on the expression of synapse specific biomarkers synaptophysin( SYP),glutamate receptor 2( GluR2) and N-methyl-D-aspartate receptor 2B( NR2B) in the hippocampus of male rats. METHODS: Forty-eight specific pathogen free adult male Wistar rats were randomly divided into control group,low-,medium-,and high-dose groups according to body weight. Each group consisted of 12 rats. By dynamic inhalation intoxication method,the control group was exposed to fresh air,the dose groups were given 1 250,2 500 and 5 000 mg / m3 of 1-BP respectively,6 hours per day,5 days per week for continuous 4 weeks. After the exposure,the rats were executed and the whole brains were separated into cerebrum( included hippocampus),brainstem and cerebellum. Real time quantitative polymerase chain reaction and Western blot were used for detection of SYP,GluR2 and NR2 B mRNA and protein expression in hippocampus. RESULTS: Slow response and muscle strength descended in hind limbs were found in high-dose group in the 3rd week. Body weights of rats in high-dose group were lower than those of control group from the 1st to the 4th week( P < 0. 01). Weights of whole brain,cerebrum and brainstem in high-dose group were lower than those of control group( P < 0. 05). Rats in high-does group were found neuron necrosis in hippocampus cornu ammonis 3 and dentate gyrus region. No significant difference was found in SYP,GluR2 and NR2 B mRNA relative expression in all groups( P > 0. 05). No significant difference was found in SYP protein relative expression in different groups( P > 0. 05). The GluR2 protein relative expression in high-dose group was lower than that of control group( P < 0. 05). The NR2 B protein relative expression was higher than that of control group( P < 0. 05). CONCLUSION: The GluR2 and NR2 B protein expression in hippocampus can be potential biomarkers for 1-BP central neurotoxicity,but its physiological meaning needs further elucidation.

Inhibitory effect of bone marrow mesenchymal stem cells on early stage of inflammation in mice exposed to silica dust / 中国职业医学

OBJECTIVE: To study the effects of bone marrow mesenchymal stem cell( BMSC) transplantation on early stage of inflammation in mice exposed to silica dust. METHODS: Specific pathogen free healthy male C57 BL /6 mice were used.Five mice were used to isolate BMSCs using bone marrow adherent method. Thirty mice were randomly divided into 3groups: control group,silica group and BMSCs transplantation group. The mice of the control group were given 20. 0 μL of0. 90% sodium chloride solution by one time intratracheal injection. The mice of silica group and the BMSCs transplantation group first received 20. 0 μL( 250 g / L mass concentration) of silicosis dust suspension by one time intratracheal injection; followed by 500. 0 μL of 0. 90% sodium chloride solution in the silica group,and 500. 0 μL of BMSCs suspension( cell density 1 × 109/ L) by tail vein infusion in the BMSCs transplantation group 6 hours later. Mice were euthanized on the 7th day of the experiments. The histopathology changes in lung tissues were examined. The serum levels of interleukin( IL)-1β, IL-6 and IL-10 were detected by enzyme linked immunosorbent assay. Real-time quantitative polymerase chain reaction was used to detect the mRNA relative expression levels of above cytokines in the lung tissues. RESULTS: The positive rates of BMSCs surface molecules cluster differentiation( CD) 29,CD34,CD90,CD105 and CD106 were 67. 70%,0. 12%,39. 00%,37. 10% and 20. 10%,respectively. Histopathology examination showed the thickened alveolar walls,broadening alveolar septum and the damaged alveolar structure in silica group. In the BMSCs transplantation group,there was no obvious damage found in the lung tissue. There was no change in the alveolar cavity and alveolar structure was complete. The IL-1β and IL-6 levels in serum and mRNA relative expression of IL-1β and IL-6in lung tissue in the silica group were higher than those of the control group and BMSCs transplantation group( P < 0. 05).The IL-1β level in serum and mRNA relative expression of IL-1β in lung tissue in the BMSCs group were higher than those of the control group( P < 0. 05). The IL-10 level in serum and mRNA relative expression of IL-10 in lung tissue in all groups showed no statistical difference( P > 0. 05). CONCLUSION: The BMSCs can alleviate pulmonary inflammatory damage at early stage by down-regulating the expression of proinflammatory factors of IL-1β and IL-6.

Effect of Ligusticum wallichii-containing serum on expressions of Toll-like receptor 4 and myeloid differentiation factor 88 in hepatic stellate cells / 中国中药杂志

To observe the effect of Ligusticum wallichii-containing serum on the expressions of Toll-like receptor 4 and myeloid differentiation factor 88 in hepatic stellate cells. Clean-grade SD rats were randomly divided into 5 groups and orally given L. wallichii decoction, colchicine and normal saline for 7 d to prepare L. wallichii-containing serums. Except for the blank group, all of the remaining groups were stimulated with LPS 1 mg x L(-1) for 24 h. After being intervened, the L. wallichii-containing serums were cultured in 5% CO2 incubator at 37 degrees C for 24 hours. The expression of TLR4 and MyD88 were detected by RT-PCR and Western blot. After HSC was stimulated with LPS, TLR4 and MyD88 mRNA and protein expressions were significantly higher than the blank control group (P < 0.01). After being intervened with L. wallichii-containing serum, TLR4 and MyD88 mRNA and protein expressions were notably lower than the model group (P < 0.05 or P < 0.01). In conclusion, L. wallichii-containing serum could regulate the TLR4 signaling pathway and show the anti-fibrosis effect by inhibiting the expression of TLR4 and MyD88 in LPS-induced HSCs.

Effect of Danshen-containing serum on expression of SuFu and DYRK2 in HSCs / 中国中药杂志

To observe the effects of Danshen-containing serum on SuFu and DYRK2 expression in the HSCs stimulated by leptin. SD rats (n = 60) were used to make danshen-containing serum by gastric perfusion for ten days with Danshen water decoction, normal saline and colchicine. The HSCs that were cultured in vitro would be stimulated for 24 hours by leptin (100 μg x L(-1)) except blank control group, after being intervened, the drug serum in each group would be cultured at 37 degrees C in 5% incubator. The cells would be collected after 24 hours, then the effects of danshen-containing serum on the proliferation of HSCs were detected by MTT, the expression of SuFu mRNA and DYRK2 mRNA were detected by RT-PCR, the expression of SuFu and DYRK2 proteins were tested by Western blot. Compared with blank control group, the expression of DYRK2 mRNA and DYRK2 proteins were enhanced obviously after stimulated the HSCs of rats by leptin (P < 0.01), but the expression of SuFu mRNA and SuFu proteins were decreased significantly (P < 0.01). Compared with the model group, after cyclopamine group (Hh pathway inhibitor), Danshen-containing serum and colchicine were interfered, the expression of DYRK2 mRNA and DYRK2 proteins were decreased clearly (P < 0.01), but the expression of SuFu mRNA and SuFu proteins were increased significantly (P < 0.01 or P < 0.05). Compared with model group, adding purmorphamine (Hh pathway agonist) to model group and making it activate could increase the expression of DYRK2 mRNA and DYRK2 proteins, but the expression of SuFu mRNA and SuFu proteins were decreased significantly (P < 0.01). Compared with the model group, using the Danshen-containing serum to interfere the purmorphamine group could make the expression of DYRK2 mRNA and DYRK2 proteins decrease and the expression of SuFu mRNA and SuFu proteins increase significantly (P < 0.01). Danshen-containing serum would inhibition the activation and increment of HSCs by interfering the expression of SuFu and DYRK2 which were induced by leptin.

Studying the changes of the related serum complement immune indexes in patients with occupational medicamentosa-like dermatitis induced by trichloroethylene and workers occupationally exposed to trichloroethylene / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To explore the mechanism of occupational medicamentosa-like dermatitis (OMDT) induced by trichloroethylene (TCE) and some immunity indexes in workers occupationally exposed to TCE.</p><p><b>METHODS</b>The blood samples from 8 cases with medicamentosa-like dermatitis in 1st, 2nd, 3rd, 4th and 5th weeks after admitting to hospital were examined for liver function, immunoglobulin and some complement indexes. Thirty nine workers occupationally exposed to TCE were investigated for urinary TCE and some immuno-complement indexes. The TCE concentrations of air in workplaces were monitored.</p><p><b>RESULTS</b>C3d-CIC and C3 of patients before admission were (92.86 ± 44.80) mg/L and 0.91 ± 0.19 mg/L, respectively. C3d-CIC and C3 of patients before discharge were (52.41 ± 17.75) mg/L and (1.14 ± 0.22) mg/L, respectively. There were significant differences between admission and discharge (P < 0.05). The average TCE concentration in 4 workplaces was (351.96 ± 36.72) mg/m(3), which was higher than the occupational exposure limits (OELs). The number of workers exposed to the TCE concentration-time weighted and TCA in urine over OELs were 28.21% and 56.41% of total subjects, respectively. The serum IgG and CIC levels of patients before discharge were (10.03 ± 1.21) mg/L and 103.50 ± 29.17 mU/L, which were significantly lower than those (17.21 ± 1.85) mg/L and (227.46 ± 111.67) mU/L of patients before admission (P < 0.01).</p><p><b>CONCLUSION</b>The type II and III hypersensitivity may be associated with OMDT and the organ injure induced by TCE.</p>

Protective effect of donator liver ischemic preconditioning on posttransplant liver graft function in Chinese miniature pigs / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the protective effect of the ischemia preconditioning of the donor liver on posttransplant liver graft function in Chinese miniature pigs.</p><p><b>METHODS</b>Twenty-five partially inbred Chinese miniature pigs were randomized into three groups, namely the normal control group, the ischemia-reperfusion group and ischemic preconditioning group. Biopsies of the liver graft were performed to analyze HSP70 expression by means of immunoblotting, and the changes of serum AST/ALT levels were assayed using an automated biochemical analyzer. Histopathological assessment was carried out to identify the hepatocyte injury using optical and transmission electron microscopy.</p><p><b>RESULTS</b>Ischemia preconditioning resulted in a notable increase in HSP70 expression and milder injury of the hepatocyte microstructure, whereas ischemia-reperfusion caused a significant increase of serum transaminases level (P<0.01) with declined HSP70 expression and obvious microstructural changes of the liver tissue.</p><p><b>CONCLUSION</b>Ischemic preconditioning can produce obvious protective effects on the donor liver, and positively regulates the expression of shock protein.</p>

Induced differentiation of bone marrow stem cells in transplanted rat liver / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the differentiation of bone marrow stem cells in transplanted livers and its impact on the long-term survival of rats with orthotopic liver transplantation.</p><p><b>METHODS</b>Twenty-four female recipient rats with orthotopic liver transplantation were randomized into blank-control group, D-hanks solution group, bone marrow stem cells group with postoperative infusion of stem cells, and the pathological changes of the liver grafts and survival time of the rats were observed. The differentiation of the bone marrow stem cells were assessed 60 days after transplantation using in situ hybridization histochemistry for Sry gene and alpha-fetoprotein (AFP) immunohistochemistry.</p><p><b>RESULTS</b>In rats with postoperative infusion of bone marrow stem cells through the portal vein, the median long-term graft survival time exceeded 180 days, significantly longer than that in the other two groups (P<0.05), and no obvious evidence of acute rejection was observed with positive Sry expression and AFP expression.</p><p><b>CONCLUSION</b>Infusion of bone marrow stem cells through the portal vein following liver transplantation may alleviate acute graft rejection and promote long-term liver graft survival and AFP expression.</p>

PDX-1 gene transfection and expression in bone marrow stromal cells-derived nestin-positive cells / 南方医科大学学报

<p><b>OBJECTIVE</b>To introduce the eukaryotic expression vector pEGFP-C1-PDX-1 into nestin-positive cell derived from bone marrow stromal cells by nucleofection and optimize the conditions for transfection.</p><p><b>METHODS</b>The recombinant plasmid was transfected into bone marrow stromal cells-derived nestin-positive cells with varied DNA quantities or the serum concentration in the medium. The expression of PDX-1 gene in the transfected cells was detected by RT-PCR.</p><p><b>RESULTS</b>Satisfactory efficiency of transfection was achieved with the DNA quantity of 2-10 microg and medium serum concentration of 20%. PDX-1 expression was detected in the transfected cells by RT-PCR.</p><p><b>CONCLUSION</b>The optimized transfection conditions result in enhanced efficiency of PDX-1 gene transfection into nestin-positive cells derived from bone marrow stromal cells, which may serve as the seed cells in tissue-engineering.</p>