Effect of programmed necrosis inhibitor Nec-1 on lead-induced BV2 cell injury / 环境与职业医学

Background Programmed necrosis is closely related to the occurrence and development of neurodegenerative diseases, but whether lead causes programmed cell necrosis has not been reported. Objective This experiment is designed to probe into the function of programmed necrosis and the effect of its inhibitor on lead-induced microglia (BV2 cell) injury. Methods The BV2 cells at logarithmic growth phase were treated with 0, 1, 5, 10, 25, 50, 100, and 200 μmol·L−1 lead acetate for 12, 24, 36, and 48 h, respectively, and methylthiazolyldiphenyl-tetrazolium bromide (MTT) was used to determine cell viability. After treatment with 0, 25, 50, and 100 μmol·L−1 lead acetate for 24 h, enzyme-linked immunosorbent assay, Western blotting, and flow cytometry were used to determine the expressions of tumor necrosis factor-α (TNF-α), receptor-interacting protein kinase 3 (RIPK3), receptor-interacting protein kinase 1 (RIPK1), and mixed lineage kinase domain-like protein (MLKL) in the cells, and the effect of RIPK1 inhibitor Nec-1 pretreatment on lead-induced BV2 cell injury . Results The BV2 cell viability decreased with higher lead concentration (r12 h=−0.995, r24 h=−0.984, r36 h=−0.983, r48 h=−0.981, all P<0.01) and time extension (only for 5 μmol·L−1 lead acetate, r=−0.994, P<0.01). Compared with the control group, the BV2 cell viability decreased at the same exposure time when the concentration of lead was above 10 μmol·L−1 (P<0.01). Compared with the control group, the expressions of RIPK1 and MLKL were increased in the 25, 50, and 100 μmol·L−1 lead groups (P<0.05 or 0.01), accompanied by an increase in the contents of inflammatory cytokine TNF-α, especially in the 100 μmol·L−1 lead group, the increment was the highest (P<0.01). The expression levels of p-RIPK1 and p-MLKL in BV2 cells were both increased when the concentration of lead acetate was above 50 μmol·L−1 (P<0.01). In addition, pretreatment with Nec-1 increased the cell viability rate and decreased the necrosis and late apoptosis rate of BV2 cells exposed to lead compared with corresponding lead exposure groups (P<0.05). Conclusions Lead can reduce BV2 cell viability, increase necrosis rate, and up-regulate the expressions of RIPK1, RIPK3, amd MLKL, and the phosphorylation levels of RIPK1 and MLKL. The RIPK1 inhibitor Nec-1 has an intervention effect on lead-induced damage in BV2 cells, indicating that programmed necrosis may play a role in lead neurotoxicity.

Advances in the application of clinical toxicology in the treatment of acute poisoning / 中华劳动卫生职业病杂志

Acute poisoning is a component of emergency medicine and a key public health problem in clinical toxicology. In recent years, the research and development of industrial chemicals and drugs have developed rapidly, and the incidence of acute drug poisoning has been increasing. It is very important to strengthen the application research of clinical toxicology in acute poisoning, to identify rare and new toxic drugs, and to create conditions for rapid detection of toxic substances. Therefore, this article reviews the types of acute poisoning, the epidemiological characteristics, the detection technology and significance of clinical toxicology, the role of clinical toxicology in the treatment of acute poisoning and its application.

Effect of air pollution on carbonylated protein level in the stratum corneum and protective effect of pink pepper tree extracts and lipid mixtures on skin damage / 中华皮肤科杂志

Objective To evaluate the effect of air pollution on carbonylated protein level in the stratum corneum,and to assess the protective effect of pink pepper tree extracts and lipid mixtures on skin damage.Methods After the investigation of influencing factors in the preliminary experiment,fluorescence labelling assay was performed to detect the carbonylated protein level in the skin stratum corneum at different body sites of 34 healthy testees.Cigarette smoke was used to simulate pollutants,and the forearms of 15 healthy testees were exposed in the customized pollution simulation chamber with the flexor aspects facing upwards.After 0,1,2,4,5 hours of exposure,stratum corneum samples were collected by using D-squame tapes.In each of 14 selected healthy testees,3 adjacent areas on the flexor aspect of unilateral forearm were divided into 3 groups:pink pepper tree group treated with 1％ aqueous solution of pink pepper tree extracts,control group treated with deionized water,and blank group receiving no treatment.Then,the forearms of the 14 testees were exposed in the pollution simulation chamber for 5 hours,and stratum corneum samples were collected from the 3 areas before and after the exposure.Another 16 healthy testees were included,and 3 adjacent areas on the flexor aspect of their unilateral forearms were divided into 3 groups:lipid mixture group treated with 5％ lipid mixture emulsion,control group treated with lipid mixture-free placebo emulsion,and blank group receiving no treatment.Then,the forearms of the 16 testees were exposed in the pollution simulation chamber for 5 hours,and stratum corneum samples were collected from the 3 areas before and after the exposure.Moreover,twenty healthy testees were enrolled into the double-blind split-face clinical trial.That is,one half of the face was randomly chosen to be treated with 1％ emulsion of pink pepper tree extracts,and the other facial side was treated with placebo emulsion.Before and after 56-day treatment,stratum corneum samples were collected from the cheeks of testees by using D-squame tapes.Fluorescence labelling assay was conducted to detect the carbonylated protein level in the above stratum corneum samples.Results The analysis of 34 testees showed that carbonylated protein levels (average fluorescence intensity) significantly differed among different body sites (P ＜0.001),and the carbonylated protein levels were significantly higher in the cheeks (26.3 ± 7.1) and forehead (22.9 ± 7.9) than in the forearm (14.7 ± 4.9) and waist and back (12.6 ± 4.2) (P ＜ 0.001),and higher in the forearm than in the waist and back (P =0.046).In the short-term simulated accelerated exposure experiment,the carbonylated protein level increased along with the increase of the duration of exposure to pollution (R2 =0.995 9).After 5-hour exposure,the pink pepper tree group and lipid mixture group both showed significantly lower elevated levels of carbonylated protein in the stratum corneum (9.7 ± 5.2,5.8 ± 4.9) compared with the corresponding blank groups (19.0 ± 10.0,17.4 ± 8.8;P ＜ 0.005) and control groups (18.5 ± 7.3,15.9 ± 6.4;P ＜ 0.005).In the long-term human trial,the carbonylated protein levels significantly decreased in the facial side treated with 1％ emulsion of pink pepper tree extracts for 8 weeks compared with the placebo-treated facial side.Conclusion Air pollution aggravates skin damage induced by protein carbonylation in the stratum corneum,and pink pepper tree extracts and lipid mixtures can effectively reduce the carbonylated protein level.

An association study between gene polymorphism of the key enzyme's folacin metabolism pathway and plasmatic homocysteine levels in fertile woman / 中华预防医学杂志

<p><b>OBJECTIVE</b>The effect of the gene polymorphism for the key enzyme's folacin metabolism pathway on plasmatic homocysteine (Hcy) levels in fertile woman was observed.</p><p><b>METHODS</b>The subjects were from Shaoxing City, Jiangsu province in 2012, the selection criteria for the women of childbearing age were between 20-45 years old, with an average age of 28.2 (95%CI:27.8-28.6) years old. Sample collection continued uninterrupted lasted seven days, a total of 535 samples were collected, venous blood with EDTA addition or sodium citrate to anticoagulant. After separation, the blood cells and blood plasma were cryopreserved. DNA was extracted using spin column method. All the samples were selected for the gene polymorphism testing of the key enzyme's on folate metabolism and monitoring of plasmatic Hcy level.</p><p><b>RESULTS</b>Eight single nucleotide polymorphism (SNP) sites of methylenetetrahydrofolate reductase gene (MTHFR) , methionine synthase gene (MS) , synthetic methionine reductase gene (MSR) and cystathionine β synthase gene (CBS) were detected. It was found the genotype AA of the SNP sites-rs1801131 would result higher plasmatic Hcy levels (8.99 µmol/L) than the genotypes CC (7.81 µmol/L) and CA(8.38 µmol/L) (P < 0.01) . Similarly, the genotype TT of the SNP sites-rs1801133 was significantly responded to the increasing of Hcy levels (11.10 µmol/L) than the genotype CC (8.15 µmol/L) and CT (8.45 µmol/L), (P < 0.01) . The two sites of genotype combination of AA-TT could also result in the significant increase of Hcy levels (11.02 µmol/L) than other combined genotypes (genotypes CC-CC, CA-CC, CA-CT, AA-CC, AA-CT), especially the genotype CC-CC. And the risk factor was 1.41 (95CI:1.20-1.66) times over the genotype CC-CC.</p><p><b>CONCLUSION</b>The gene mutations of two SNP sites rs1801131 and rs1801133 in MTHFR would increase Hcy levels.</p>

Analysis of risk factors for children with incomplete Kawasaki disease / 中国综合临床

ObjectiveTo study the risk factors for children with incomplete Kawasaki disease(IKD) to decrease the development of coronary artery lesions (CAL).MethodsAll children diagnosed as IKD from Jan.2005 to Apr.2011 in our department were reviewed retrospectively for their clinical data,laboratory values and treatment measures.ResultsEight of the children (8/36,22.2％ ) were positive for CAL.The count of white blood cell( WBC),count of platelet(PLT),hematocrit and C reactive protein(CRP) level were ( 18.36 ± 4.63) × 109/L,(450.30 ± 155.40) × 109/L,( 25.63 ± 3.53 ),( 18.30 ± 3.80) mg/L and ( 13.48 ±3.27) × 109/L,(350.60 ± 56.80) × 109/L,( 33.78 ± 2.24 ),(9.70 ± 2.50) mg/L in the CAL group and non-CAL group respectively.And there were significant differences on the four indexes between CAL group and non-CAL group ( t =2.58,2.65,2.73,2.48,respectively,P ＜ 0.05 ).Pyretolysis time of children first undergoing globulin treatment was (2.5 ± 1.5 ) d and ( 1.5 ± 1.0 ) d in children under 1-year old and those above l-year old respectively,and the difference was significant ( t =2.35,P ＜ 0.05).ConclusionCAL should be cautiously prevented in IKD infants under l-year old with a fever lasting for over 5 days,decreased hematocrit and elevated WBC count,PLT count,Hct and CRP.Infant IKD patients are not so sensitive to intravenous gamma globulin and tend to occur CAL.They should be given an early diagnosis and timely treatment.

Analysis of the relationship between mycoplasma pneumoniae infection and children asthma / 中国基层医药

Objective To study the relationship between mycoplasma pneumoniae(MP) infection and children asthma,and to observe the treatment effects of macrolide antibiotics (azithromycin) on mycoplasma pneumoniae infection.Methods 250 children of respiratory disease were investigated with olimpus electron gastroscope,200 children asthma;the serum specific antibodies were determined by Diagnostic Kit for measurement of antibodies to mycoplasma pneumoniae (Passive Particle Agglutination) ;and the eosinophilic grannlocytes were serologically analyzed in children with recent asthma.Random selection 42 MP infection positive to macrolides antibiotics (azithromycin) treatment.Results 44 MP infection positive,200 children asthma cases had MP infection with 21％ (42/200) MP positive,the specific antibody titers to MP showed significant difference in children with recent asthma compared with those in the contol group ( x2 =6.14,P ＜ 0.05 ),and correlated with the count of eosinophilic granulocy positively ( r =0.603,P ＜ 0.05) ;The positive rates of specific antibody,infection with MP were significantly higher than those in the control group( t =4.38,P ＜ 0.05 ).MP infection positive group with azithromycin treatment effect is significantly higher than that of cefuroxime group ( x2 =16.18,P ＜ 0.05 ).Conclusion MP infection is closely associated with the pathogenesis of children asthma;and early routine testing for MP antibodies.Macrolides antibiotics can eliminate MP infection,a new generation of macrolides antibiotics(azithromycin) is more advantageous to the control of acute attack of asthma.

Application of routine MRI and 1H-MRS in evaluating the central neurological damages caused by occupational manganese exposure / 中华放射学杂志

Objective MRI and MR hydrogen proton spectroscopy (1H-MRS) were used to detect the abnormal signal and alteration of metabolites, in order to explore the efficacy of these method in evaluating the damages of central nervous system (CNS) induced by occupational manganese exposure.Methods Eighteen workers exposed to manganese without any manganism symptoms, 12 workers with slightly chronic manganese poisoning, and 19 healthy workers were scanned using routine MRI sequence and 1H-MRS.The blood manganese concentration was also collected for each subject.On cerebral axial T1 WI,the signal intensities of ipsilateral globus pallidus and frontal white matter were measured in the visually brightest area (try to select the signal homogeneous region), and the globus pallidus index (PI) was then calculated.The 1H-MRS data was calculated to get the values of the peak height of N-acetylaspartate (NAA), choline (Cho), inositol (mI) and creatine (Cr) and the ratios of NAA/Cr, Cho/Cr, and mL/Cr were also calculated.One way ANOVA was used to compare the values of PI, NAA/Cr, Cho/Cr, mI/Cr and MnB among the three groups, and the correlations between PI and the time span of manganese exposure or blood manganese concentration were analyzed by Pearson correlation analysis.Eight workers exposed to manganese were followed up one year, and their PI , NAA/Cr before and after follow-up were compared by t test.Results Fourteen of 18 cases exposed to manganese without any manganism symptoms showed symmetrically high intensity signal on T1 WI, while the T2 WI were normal.No high signal intensity was observed on T1WI in any of the healthy workers or manganese poisoning workers.We found that the average PI in manganese exposed group (1.16 ±0.09) was significantly higher (F =24.79 ,P =0.O00)than those of the poisoning ( 1.05 ± 0.07 ) and control groups ( 1.01 ± 0.05 ).The blood manganese concentration in manganese exposed group, the poisoning group and the control group were (0.051 ±0.024), (0.047 ±0.018 ), ( 0.043 ± 0.020 ) μg/ml respectively, which was not significantly different ( F = O.623, P =0.541 ) and did not exceed the upper limit of normal reference value ( < 0.10 μg/ml ).There was a significantly correlation between PI and the time span of manganese exposure ( r = 0.67, P = 0.002 ),however, there was no correlation between PI and blood manganese concentration ( r = 0.20, P = 0.427 ).Furthermore, the NAA/Cr ratio decreased variously in the manganese poisoning group ( 1.22 ± 0.07 ) which was significantly lower( F = 4.120, P = 0.023 ) than those of the poisoning( 1.33 ± 0.13 ) and control groups ( 1.31 ±0.13).No statistical significanees were found in the ratios of Cho/Cr and mI/Cr among these three groups(P>0.05).No obvious changes of the PI and NAA/Cr were found in the 8 manganese exposed workers after 1 year follow-up.Conclusion Manganese exposure could lead to the high intensity signal on T1 WI, therefore the increased PI may be the biomarkers of central nerve system damages caused by the occupational manganese exposure.