Effect of Dichloromethane Extraction Phase of Patrinia Scabiosaefolia Fisch. Stem on Proliferation and Differentiation of K562 Cells / 中国实验血液学杂志

OBJECTIVE@#To explore the effect of dichloromethane extraction phase of ethanol extract from stem of Patrinia scabiosaefolia Fisch.(DPSS) on proliferation and differentiation of K562 cells and its related mechanism.@*METHODS@#MTT assay was used to detect the effects of DPSS at 0, 25, 50, 100 and 200 μg/ml on the proliferation of K562 cells at 24, 48 and 72 hours. Flow cytometry was used to analyze the changes of cell cycle and apoptosis at 24 and 48 hours. Wright-Giemsa staining was used to observe the morphological changes of K562 cells. The cell surface antigens CD33 and CD11b were detected by flow cytometry.@*RESULTS@#The proliferation of K562 cells treated with different concentrations of DPSS was inhibited in a time-dose dependent manner (r=-0.96). Cell cycle analysis showed that with the increase of DPSS concentration, cells in G2/M phase increased (r=0.88), and cells were blocked in G2/M phase. Flow cytometry results showed that with the apoptosis rate of K562 cells was the highest when treated with 200 μg/ml DPSS for 48 h. Morphological observation showed that the K562 cell body increased, the amount of cytoplasm increased, the ratio of nucleus to cytoplasm decreased, and the nuclear chromatin was rough after DPSS treatment. Cell differentiation antigen, CD33 and CD11b, were positively expressed after treated with DPSS.@*CONCLUSION@#DPSS can induce apoptosis through cell cycle arrest, inhibit the proliferation of K562 cells, and induce K562 cells to differentiate into monocytes, which has a potential anti-leukemia effect.

Free energy perturbation (FEP)-guided scaffold hopping

Scaffold hopping refers to computer-aided screening for active compounds with different structures against the same receptor to enrich privileged scaffolds, which is a topic of high interest in organic and medicinal chemistry. However, most approaches cannot efficiently predict the potency level of candidates after scaffold hopping. Herein, we identified potent PDE5 inhibitors with a novel scaffold via a free energy perturbation (FEP)-guided scaffold-hopping strategy, and FEP shows great advantages to precisely predict the theoretical binding potencies ΔG FEP between ligands and their target, which were more consistent with the experimental binding potencies ΔG EXP (the mean absolute deviations | Δ G FEP - Δ G EXP |  < 2 kcal/mol) than those ΔG MM-PBSA or ΔG MM-GBSA predicted by the MM-PBSA or MM-GBSA method. Lead L12 had an IC50 of 8.7 nmol/L and exhibited a different binding pattern in its crystal structure with PDE5 from the famous starting drug tadalafil. Our work provides the first report via the FEP-guided scaffold hopping strategy for potent inhibitor discovery with a novel scaffold, implying that it will have a variety of future applications in rational molecular design and drug discovery.

Facile synthesis of insulin fusion derivatives through sortase A ligation

Insulin derivatives such as insulin detemir and insulin degludec are U.S. Food and Drug Administration (FDA)-approved long-acting insulin currently used by millions of people with diabetes. These derivatives are modified in C-terminal B29 lysine to retain insulin bioactivity. New and efficient methods for facile synthesis of insulin derivatives may lead to new discovery of therapeutic insulin. Herein, we report a new method using sortase A (SrtA)-mediated ligation for the synthesis of insulin derivatives with high efficiency and functional group tolerance in the C-terminal B chain. This new insulin molecule (Ins-SA) with an SrtA-recognizing motif can be conjugated to diverse groups with N-terminal oligoglycines to generate new insulin derivatives. We further demonstrated that a new insulin derivative synthesized by this SrtA-mediated ligation shows strong cellular and

Identification of ferroptosis as a novel mechanism for antitumor activity of natural product derivative a2 in gastric cancer

Ferroptosis is a type of cell death accompanied by iron-dependent lipid peroxidation, thus stimulating ferroptosis may be a potential strategy for treating gastric cancer, therapeutic agents against which are urgently required. Jiyuan oridonin A (JDA) is a natural compound isolated from Jiyuan

Quantitative assessment of occupational health risks in workers exposed to low-level dichloromethane / 中国职业医学

OBJECTIVE: To quantitatively evaluate the non-carcinogenic and carcinogenic risks of low-level dichloromethane(DCM) exposure. METHODS: A typical sampling method was used to select workers from an engine factory and an automobile parts factory as the research subjects. After hazard identification and hazard characteristic assessment, the occupational health risks of DCM in the workplace were quantitatively assessed by non-carcinogenic risk assessment and carcinogenic risk assessment. RESULTS: The highest exposure concentration of short-term of DCM was 43.6 mg/m~3 in the air of eight DCM job posts in these two enterprises, which was lower than the operational level of 300.0 mg/m~3(half of the occupational exposure limit in China). Under this premise, the non-carcinogenic risk assessment results showed that the non-carcinogenic risk caused by inhalation of DCM was unacceptable in workers of these eight job posts. The results of carcinogenic risk assessment showed that the carcinogenic risk caused by inhalation of DCM was acceptable for all the workers in these eight job posts. CONCLUSION: Low-level DCM exposure can cause unacceptable occupational health risks to workers. Quantitative risk assessment can be applied to assess exposure to low-level chemicals.

Anti-acetylcholinesterase Active Ingredients from Aconitum tanguticum by UPLC-Q-TOF-MS/MS / 中国实验方剂学杂志

Objective:To identify the anti-acetylcholinesterase active ingredients in <italic>Aconitum tanguticum</italic>， so as to lay the foundation for finding new anti-Alzheimer's disease （AD） drugs. Method:The anti-acetylcholinesterase active fractions of <italic>A. tanguticum</italic> were screened by the modified Ellman's method， and the chemical composition of the active fraction was analyzed by ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry （UPLC-Q-TOF-MS/MS）. The chromatographic separation was performed on an ACQUITY UPLC BEH C₁₈ column （2.1 mm×50 mm， 1.7 μm） with acetonitrile （A）-0.4% ammonia aqueous solution （B） as mobile phase for gradient elution， and the column temperature was set at 30 ℃ with the flow rate of 0.4 mL·min^-1. Phase A of the dichloromethane fraction changed with time as follows：0-3 min， 5%A； 3-7 min， 5%-20%A； 7-11.5 min， 20%-33%A； 11.5-15.5 min， 33%-50%A； 15.5-20.5 min， 50%-80%A； 20.5-23 min， 80%-85%A； 23-25 min， 85%-95%A. Phase A of the <italic>n</italic>-butanol fraction changed with time as follows：0-2 min， 5%A； 2-8 min， 5%-20%A； 8-11 min， 20%-33%A； 11-15 min， 33%-95%A. Mass spectrometry was performed on electrospray ionization， data were collected in positive ion mode， and the detection range was <italic>m</italic>/<italic>z</italic> 100-1 500. Result:Both the dichloromethane and <italic>n</italic>-butanol fractions had a certain inhibitory effect on acetylcholinesterase， their half inhibitory concentration （IC₅₀） values were （64±4.4） mg·L^-1 and （85.7±3.8） mg·L^-1， respectively. By UPLC-Q-TOF-MS/MS analysis， a total of 21 alkaloids were identified from the dichloromethane fraction， and 11 alkaloids were identified from <italic>n</italic>-butanol fraction. Guan-fu base Ⅰ， found in both fractions， was first discovered in <italic>A. tanguticum</italic>. Conclusion:Diterpene alkaloids are the main anti-acetylcholinesterase substances of <italic>A. tanguticum</italic>， which is worth further exploration.

Improvement of detection method for anionic synthetic detergents in drinking water / 公共卫生与预防医学

Objective To detect anionic synthetic detergents in drinking water with dichloromethane as the extracting agent using an automatic anionic detergent online extraction analysis system. Methods Anionic synthetic detergent in water reacted with methylene blue dye to produce blue compounds. Dichloromethane was used instead of chloroform for extraction. The automatic anionic detergent on-line extraction and analysis system was used for color comparison and quantification. Results The linear relationship of the anionic synthetic detergents was good in the range of 0 mg /L～0.50 mg /L with a correlation coefficient being greater than 0.9990. The relative standard deviation was 1.08%～4.63%, the recovery was 93.76%～106.64%, and the method detection limit was 0.004 mg /L. Conclusion This method used dichloromethane as an extractant to determine anionic synthetic detergents in drinking water, and obtained satisfactory results. At the same time, full automation kept the detection environmental conditions of different samples consistent, saved labor and further improved the safety of operators.

Comparison of two risk assessment methods to assess occupational health risk in key industries of dichloromethane in Shenzhen City / 中国职业医学

OBJECTIVE: To compare the applicability of two risk assessment methods to assess the occupational health risk of key industries of dichloromethane in Shenzhen City. METHODS: The Singapore ministry of manpower risk(MOM) method and the comprehensive index method were used to evaluate the risk of 123 positions in 47 key industries of dichloromethane in Shenzhen City. Then the risk classification results of the two assessment methods were compared. RESULTS: The results of MOM method showed that the median and the 0 th to 100 th percentile [M(P_0-P_(100))] of risk of dichloromethane in electronics industry was 2(2-3), and the risk level was low to medium. The M(P_0-P_(100)) of risk of dichloromethane in printing industry was 2(2-4), and the risk level was low to high. The results of the comprehensive index method showed that the M(P_0-P_(100)) of risk of dichloromethane in electronics industry and printing industry were 3(3-4), and the risk level was medium to high. There was no significant difference in the assessment results of occupational health risk of dichloromethane between the electronic industry and the printing industry by MOM evaluation method(P>0.05). The occupational health risk assessment of dichloromethane in printing industry was higher than that in electronic industry by the comprehensive index method(P<0.01). Both evaluation methods were not consistent in the electronics industry and the printing industry(k values were-0.01 and 0.04, all P>0.05). After merging the evaluation results of the two industries, there was no consistency in the evaluation results of the two evaluation methods(k value=0.01, P>0.05). CONCLUSION: The risk level of dichloromethane in printing industry is higher than that in printing industry in Shenzhen City. The comprehensive index method may comprehensively and objectively assess the occupational health risk level of dichloromethane in key industries in Shenzhen City.

Chlorella sorokiniana and Chlorella minutissima exhibit antioxidant potentials, inhibit cholinesterases and modulate disaggregation of ß-amyloid fibrils

BACKGROUND: Microalgae are aquatic chlorophyll-containing organisms comprising unicellular microscopic forms, and their biomasses are potential sources of bioactive compounds, biofuels and food-based products. However, the neuroprotective effects of microalgal biomass have not been fully explored. In this study, biomass from two Chlorella species was characterized, and their antioxidant, anticholinesterase and anti-amyloidogenic activities were investigated. RESULTS: GC­MS analysis of the extracts revealed the presence of some phenols, sterols, steroids, fatty acids and terpenes. Ethanol extract of Chlorella sorokiniana (14.21 mg GAE/g) and dichloromethane extract of Chlorella minutissima (20.65 mg QE/g) had the highest total phenol and flavonoid contents, respectively. All the extracts scavenged 2,2-diphenyl-1-picrylhydrazyl, 2,2-azinobis (3-ethylbenzothiazoline-6-sulfonate) and hydroxyl radicals. The highest metal chelating activity of the extracts was observed in the ethanol extracts of C. minutissima (102.60 µg/mL) and C. sorokiniana (107.84 µg/mL). Furthermore, the cholinesterase inhibitory activities of the extracts showed that ethanol extract of C. sorokiniana (13.34 µg/mL) exhibited the highest acetylcholinesterase inhibitory activity, while dichloromethane extract of C. minutissima (11.78 µg/mL) showed the highest butyrylcholinesterase inhibitory activity. Incubation of the ß-amyloid protein increased the aggregation of amyloid fibrils after 96 h. However, ethanol extract of C. sorokiniana and C. minutissima inhibited further aggregation of Aß1­42 and caused disaggregation of matured protein fibrils compared to the control. This study reveals the modulatory effects of C. sorokiniana and C. minutissima extracts on some mediators of Alzheimer's disease and provides insights into their potential benefits as functional food, nutraceutics or therapeutic agent for the management of this neurodegenerative disease.

Cardiotoxicity in Zebrafish Embryos of Euphorbiae Pekinensis Radix Before and After Processing with Vinegar / 中国实验方剂学杂志

Objective:Taking zebrafish embryos as research model, to investigate the toxic effect of different polar fractions of Euphorbiae Pekinensis Radix before and after processing with vinegar on heart. Method:Zebrafish embryos with normal development at 12 h after fertilization were treated with petroleum ether, dichloromethane and ethyl acetate extracts of Euphorbiae Pekinensis Radix before and after processing with vinegar for observation of cardiac development and function at 72 h. Result:Various polar fractions of Euphorbiae Pekinensis Radix before and after processing with vinegar had the cardiotoxicity on zebrafish embryos in a dose-dependent manner. In addition, the cardiotoxicity of different polar fractions was followed by petroleum ether, dichloromethane and ethyl acetate. The cardiotoxicity was mainly manifested as slow cardiac development, pericardial edema, decrease of heart rate and apoptosis of cardiac cells. Compared with the corresponding polar fraction of raw products, the cardiotoxicity of the same polar fraction of vinegar-processed products with similar doses decreased. Conclusion:Euphorbiae Pekinensis Radix has cardiotoxicity to zebrafish embryos and the cardiotoxicity is reduced after processing with vinegar, which can provide some experimental basis for further elucidation of the detoxication mechanism of Euphorbiae Pekinensis Radix processed with vinegar.

Simultaneous Determination of Six Residual Solvents in Phenylbutazone Raw Material by Head-space GC / 中国药房

OBJECTIVE： To establish a method for simultaneous determination of residual solvents in phenylbutazone raw material. METHODS： Head-space GC was adopted. The determination was performed on Agilent HP-5 capillary column by temperature programming. The temperature of injector was 200 ℃， and detector was flame ionization detector with temperature of 250 ℃； carrier gas was nitrogen （purity：99.99％） at the flow rate of 2.0 mL/min. The split ratio was 5 ∶ 1. Headspace equilibrium temperature was 60 ℃， and equilibration time was 30 min. The sample size was 1 mL. RESULTS： The linear range was 0.15-4.5   μg/mL for methanol （r＝0.999 9）， 0.25-7.5 μg/mL for ethanol （r＝0.999 7）， 0.25-7.5 μg/mL for isopropyl alcohol （r＝0.999 7）， 0.03-0.9 μg/mL for dichloromethane （r＝0.999 3）， 0.25-7.5 μg/mL for ethyl acetate （r＝0.999 3）， 0.044-1.32 μg/mL for N，N-dimethyl formamide （r＝0.999 3）， respectively. The limits of detection were 0.05， 0.08， 0.08， 0.01， 0.08， 0.015 μg/mL. The limits of quantitation were 0.15， 0.25， 0.25， 0.03， 0.25， 0.044 μg/mL. RSDs of precision test were lower than 2.0％. RSDs of stability and reproducibility tests were lower than 3.0％. The recoveries were 98.75％-100.12％ （RSD＝0.56％， n＝9）， 98.07％-101.20％ （RSD＝1.12％， n＝9）， 98.36％-100.80％ （RSD＝0.92％， n＝9）， 98.33％-101.67％ （RSD＝0.98％， n＝9）， 98.11％-100.40％ （RSD＝0.72％， n＝9） and 98.75％-101.05％ （RSD＝0.89％， n＝9）. CONCLUSIONS： The method is simple， accurate， precise， stable， reproducible and durable， and can be used for simultaneous determination of 6 residual solvents in phenylbutazone raw material.

Dichloromethane-Induced Chemical Burn of the Hand: A Report of Two Cases

Detecting three halogenated hydrocarbons in blood by gas chromatography-mass spectrometry / 中国职业医学

OBJECTIVE: To establish a method for detecting dichloromethane,trichloromethane and 1,2-dichloroethane in blood by gas chromatography-mass spectrometry. METHODS: Using static headspace analysis, three halogenated hydrocarbons in blood samples were separated by DB-5 MS elastic capillary column and detected by gas chromatographymass spectrometry. RESULTS: There was a good linear relationship in the selected range of dichloromethane,trichloromethane and 1,2-dichloroethane in blood. The linear correlation coefficient was greater than 0. 999 8. The detection limit and the lower limit of quantitation was 0. 19-0. 28 and 0. 64-0. 93 μg/L,respectively. The average recovery rate was 95. 1%-106. 6%. The within-run and between-run relative standard deviation was 2. 9%-4. 9% and 5. 0%-7. 0%,respectively. The samples could be preserved at room temperature or 4 ℃ for 3 days and at-8 ℃ or below for7 days. CONCLUSION: With the features of high sensitivity,precision,accuracy,easy operation and less interference,this method is suitable for detecting dichloromethane,trichloromethane and 1,2-dichloroethane in the blood.

Anti-biofilm activity against Staphylococcus aureus MRSA and MSSA of neolignans and extract of Piper regnellii

ABSTRACT Many infections worldwide are associated with bacterial biofilms. The effects of isolated neolignans (conocarpan and eupomathenoid-5) and the dichloromethane extract of Piper regnellii (Miq.) C. DC., Piperaceae, were tested against isolates of methicillin-resistant Staphylococcus aureus and methicillin-sensitive S. aureus biofilms and S. aureus planktonic cells. The dichloromethane extract presented better results than isolated neolignans against all of the biofilms tested, with a minimum inhibitory concentration <400 µg/ml for preformed biofilms and minimal biofilm inhibitory concentration of 15.6 µg/ml for biofilm formation. The minimum inhibitory concentration to planktonic cells was <12.5 µg/ml. These results indicate a good effect of the dichloromethane extract against methicillin-resistant S. aureus and methicillin-sensitive S. aureus biofilms and efficient prophylaxis.

Simultaneous Determination of 6 Residual Organic Solvents in Omeprazole Magnesium by Headspace GC / 中国药房

OBJECTIVE:To establish a method for the simultaneous determination of 6 kinds of residual organic solvents in Omeprazole magnesium,such as methanol,isopropanol,acetonitrile,dichloromethane,ethyl acetate and toluenein. METHODS:Headspace GC was adopted. The determination was performed on the column of DB-624 column by temperature programming. The inlet temperature was 200 ℃,and hydrogen flame ionization detector was adopted with the temperature of 250 ℃;nitrogen gas was used as carrier gas with flow rate of 2.0 mL/min;the splitting-radio was 5 : 1,and sample size was 1 mL;the headspace tem-perature was 80 ℃ and the equilibrium time was 20 min. RESULTS:The linear range were 12.56-628.00 μg/mL for methanol(r=0.9997),20.22-1011.20 μg/mL for isopropanol(r=0.9999),1.96-97.76 μg/mL for acetonitrile(r=0.9997),3.10-154.88 μg/mL for dichloromethane(r=0.9998),20.69-1034.56 μg/mL for ethyl acetate(r=0.9998),and 3.53-176.72 μg/mL for toluene(r=0.9998);the limits of quantitation were 1.00,0.91,0.47,0.93,0.41 and 0.35 μg/mL respectively;the limits of detection were 0.31,0.30,0.14,0.31,0.12 and 0.11 μg/mL respectively;RSDs of precision,stability and reproducibility tests were lower than 3%;the recoveries were 94.53%-101.29%(RSD=2.15%,n=9),97.78%-103.42%(RSD=1.77%,n=9),96.99%-105.76%(RSD=2.59%,n=9),96.83%-102.05%(RSD=1.86%,n=9),97.98%-101.13%(RSD=0.88%,n=9)and 97.80%-102.40%(RSD=1.41%,n=9). CONCLUSIONS:The method is sensitive and accurate,can be used for the simultaneous determination of 6 kinds of residual organic solvents in Omeprazole magnesium,such as methanol,isopropanol,acetonitrile,dichloromethane,eth-yl acetate and toluenein.

Simultaneous Determination of 4 Residual Organic Solvents in Lacidipine Raw Material by GC / 中国药房

OBJECTIVE:To establish a method for simultaneous determination of 4 residual organic solvents such as ethanol,dichloromethane,isopropanol and ethyl acetate in lacidipine raw material.METHODS:GC method was adopted.The determination was performed on DB-624 capillary column at the rate of 2.0 mL/min using nitrogen gas as carrier and FID as the detector by temperature programming.The temperature of detector was set at 250 ℃.Carries gas was nitrogen.The split ratio was 10 ∶ 1.The sample size was 10 μL.RESULTS:The linear ranges of ethanol,dichloromethane,isopropanol and ethyl acetate were 0.259 5-2.076 mg/mL (r=0.999 6),0.055 3-0.316 mg/mL (r=0.999 2),0.342 3-1.956 mg/mL (r=0.999 5),0.370 6-2.118 mg/mL(r=0.999 4),respectively.The limits of quantification were 2.96,2.24,4.4,4.44 μg/mL,and the detection limits were 0.887,0.672,1.3,1.32 μg/ mL,respectively.RSDs of precision,stability and reproducibility tests were all lower than 4.0％.The recoveries were 95.00％-101.17％ (RSD=2.19％,n=9),96.22％-104.53％ (RSD=3.27％,n=9),96.20％-104.90％ (RSD=2.41％,n=9),95.60 ％-104.48 ％ (RSD=2.85 ％,n=9).CONCLUSIONS:The method is simple,sensitive and reliable,and is suitable for simultaneous determination of 4 residual organic solvents in lacidipine raw material.

Simultaneous Residual Determination of Two Organic Solvents in Bisacodyl Raw Material by Head-space GC / 中国药房

OBJECTIVE:To establish a method for simultaneous residual determination of dichloromethane and ethyl acetate in bisacodyl raw material. METHODS:Head-space GC was performed on the capillary column of 6% cyanopropyl phenyl-94% di-methyl polysiloxane(DB-624)by temperature programming,the temperature of injector was 220 ℃,detector was flame ionization detector with temperature of 250 ℃,carrier gas was high purity nitrogen with the flow rate of 3.0 ml/min,split ration was 1∶10, headspace heating temperature was 70 ℃,equilibration time was 30 min,volume of headspace vial was 5 ml,and the injection volume was 1 ml. RESULTS:The linear range was 6-120μg/ml for dichloromethane(r=0.999 9)and 50-1 000μg/ml for ethyl ac-etate(r=0.999 9);the limit of quantitation was 0.2,1.7 μg,limit of detection was 0.06,0.5 μg;RSDs of precision,stability and reproducibility tests were no higher than 3%;recoveries were 100.30%-102.00%(RSD=0.63%,n=9) and 100.10 %-101.30%(RSD=0.44%,n=9). CONCLUSIONS:The method is simple and accurate,and can be used for the simultaneous residual deter-mination of dichloromethane and ethyl acetate in bisacodyl raw material.

A study on the effect of repeated -dose toxicity on rats exposed to dichloromethane by dermal route for 28 days / 预防医学

Objective To learn the toxic effects on rats repeatedly exposed to dichloromethane by dermal route at the same dose for 28 days.Methods Seventy two Sprague Dawley rats were divided into six groups:a solvent control group (oliver oil),four exposure groups (0.75,1.5,3.0 and 6.0 g/kg·BW)and a recovery group.Each group included six female and six male rats.The exposure groups were dermal exposed to DCM at 1.5,3.0 and 6.0 g/kg·BW,6 hours/day,5 days/week for four weeks.The recovery group was dermal exposed to 6.0 g/kg BW of DCMduring the same period then recovered for 2 weeks.Clinical signs including body weight and food consumption of each group were observed.After rats were sacrificed,the hematological and serum biochemical parameters were determined.Histopathological examination was performed on selected tissues for all animals.Results The male rats in test groups including four exposure groups and a recovery group,showed decreased body weight gain.Neutrophilia and lymphocytopenia were determined in females of 3.0 and 6.0 g/kg BW groups and males of 1.5,3.0 and 6.0 g/kg BW groups by blood routine test (P <0.05).The mean levels of serum ALT and AST significantly increased in males of 3.0 and 6.0 g/kg BW groups (P <0.05).Only the mean level of serum TG in males of 6.0 g/kg BW group decreased (P <0.05).No significant differences of these indexes were shown in female rats of all exposure groups compared to control group.The exposure -related significant increases on the incidences of epidermis and dermis lesion,hepatocellular degeneration and necrosis were observed in test groups compared to the control group.The rats of recovery group were exhibited normal percentages of lymphocytes and neutrophils,levels of ALT,AST and TG. The skin and hepatocellular lesion were improved to some extent, but not recovered exactly.Conclusion In a 4 -week repeated -dose toxic study,DCM induce dose -related effects in rats involving skin lesion and liver injury with adverse changes in body weight gain of male rats,part parameters of hematology and serum biochemistry .

IgA nephropathy in a laboratory worker that progressed to end-stage renal disease: a case report

BACKGROUND: IgA nephropathy (IgAN) is the most common form of glomerulonephritis, a principal cause of end-stage renal disease (ESRD) worldwide. The mechanisms of onset and progression of IgAN have not been fully revealed, and epidemiologic studies have yielded diverging opinions as to the role of occupational exposure to organic solvents in the initiation or worsening of IgAN. As the authors encountered a laboratory worker with IgAN that progressed to ESRD, we present a case report of IgAN progression due to dichloromethane exposure along with a review of literature. CASE PRESENTATION: A 41-year-old male laboratory worker began to experience gross painless hematuria after two years of occupational exposure to toluene. Although clinical follow-up was initiated under the impression of IgAN based on clinical findings, the patient continued to work for four more years in the same laboratory, during which he was in charge of laboratory analysis with direct exposure to a high concentration of dichloromethane without proper protective equipment. During that time, his renal function rapidly worsened and finally progressed to ESRD 10 years after the first clinical symptoms. The result of exposure assessment through reenactment of his work exceeded the occupational exposure limit for dichloromethane to a considerable degree. CONCLUSIONS: The causal association between occupational solvent exposure and IgAN is still unclear; therefore, this case report could be used as a basis to support the relevance of occupational solvent exposure to IgAN and/or its progression. Early intervention as well as close monitoring of laboratory workers exposed to various organic solvents is important to prevent or delay the progression of glomerulonephritis to ESRD in the occupational setting.

A study on the influence of dichloromethane exposure on liver function among furniture manufacturing workers / 预防医学

Objective To explore the effects of dichloromethane(DCM)exposure on serum biochemical indexes among furniture manufacturing workers. Methods A total of 65 workers who engaged in adhesive operations in furniture manufactory and 56 workers who would be recruited into another factory as new employees were investigated. Twenty two pairs of workers were selected as occupationally exposure group and control group,respectively. The concentration of DCM in workplace of adhesive operations in furniture manufactory was determined. Serum levels of TP,ALB,GloB,A/ G, ALT,AST,GGT,AFU,GPDA,ADA,ALP,CHE,CHOL,TG,TBA,TBIL,DBIL and IBIL were tested by automatic biochemical analyzer in all groups. Results The mean levels of serum TP,ALB,GloB in exposure group( the concentrations of DCM in workplace were 1 300 - 7 760 mg/ m3 )were 73. 7 ± 3. 6,47. 5 ± 2. 3 and 26. 2 ± 2. 8 g/ L,which were significantly lower than that of control group(P < 0. 05). Compared to the control group,the mean levels of CHE, ADA,AST and ALT activity in exposure group(7 477. 8 ± 1 240. 8,7. 3 ± 1. 7,21. 6 ± 5. 6 and 13. 0 ± 5. 6 U/ L)were significantly lower(P < 0. 05). The mean levels of TBIL,DBIL and IBIL were 13. 9 ± 7. 6,6. 4 ± 4. 3 and 7. 5 ± 3. 4μmol/ L,respectively,which were significantly higher than that of control group(P < 0. 05). No significant difference in the mean levels of the other biochemical indexes in serum was observed between exposure and control group. However,no correlation was found between the levels of ALB and TBIL,ALB and DBIL,or ALB and IBIL. Conclusion Occupational exposure to DCM is associated with the decrease of TP,ALB,GloB and CHE levels in serum. Meanwhile,DCM occupational exposure is correlated with the increase of TBIL,DBIL and IBIL levels in serum. Our data suggest that occupational exposure to DCM may be related to inhibition of synthetic function in live,damage of blood cells and declined metabolism of bilirubin.