Objective To explore the DNA damage in peripheral blood lymphocytes of rats exposed to sodium arsenite. Methods Thirty-two Wistar rats, weighing 180 - 200 g, equal male and female, were randomly divided into 4 groups, 8 in each group. Sodium arsenite 0(control) ,0.05,0.15,0.45 mg/L were given through drinking water for 30 days. Body weight and drinking water consumption were measured every day. Blood were collected and DNA damage in peripheral blood lymphocytes was examined by single cell gel electrophoresis.Results The increase of body mass[( 121.00 ± 38.57), ( 120.62 ± 42.80), ( 125.38 ± 48.68)g]and water intake [(36.9 ± 6.2), (37.9 ± 5.8), (39.3 ± 4.2)ml/d]in 0.05,0.15,0.45 mg/L sodium arsenite groups were compared with the control group[( 119.25 ± 47.27)g, (38.4 ± 5.1 )ml/d], and the difference were not significant (F = 0.040,0.828, all P ＞ 0.05). The tail ratios[46.25%(185/400) ,57.00%(228/400),64.00%(256/400)], tail lengths [(32.89 ± 17.18), (58.74 ± 36.28), (77.55 ± 35.73 ) μm]and tail moments [(6.29 ± 3.74), ( 11.20 ± 9.64),(17.30 ± 12.60)μm]in 0.05,0.15,0.45 mg/L sodium arsenite groups were significantly higher than those of the control group[39.25%(157/400), (18.73 ± 15.83),(2.61 ± 1.05)μm, all P ＜ 0.01], and the tail ratios,tail lengths and tail moments in lymphocytes increased with increased doses of arsenic concentration. Conclusions Low doses of arsenic exposure can induce DNA damage in peripheral blood lymphocytes of rats.

We report one case of pediatric acute myeloid leukemia type 2 (AML-M2) who presented with karyotypic aberration of trisomy 21 with the t(5;ll) chromosomal translocation.The patient achieved complete remission after two cycles of chemotherapy of daunorubicin,cytarabine and etoposide.Then,follow-up cytogenetic analysis from bone marrow cell cultures demonstrated a normal karyotype of 46,XY.After 9 years,the patient relapsed and the karyotypic abnormalities of trisomy 21 with t(5;ll) reappeared.It was concluded that trisomy 21 with t(5;11) is a new unfavorable cytogenetic aberration in AML-M2.

Objective: To analyze the relationship between thrombin activatable fibrinolysis inhibitor ( TAFI ) and coronary heart disease ( CHD ), and to provide evidence for the prevention of CHD. Methods: The patients with CHD in Fushun Central Hospital in Liaoning Province were selected as the case group, the patients without CHD in the same hospital and period were selected as the control group. The demographic information and clinical examination results ( serum TAFI, lipid, glucose, etc. ) were collected to analyze the association between TAFI and CHD by logistic regression models.The multivariate logistic regression analysis was used to explore the relationship between TAFI and CHD. Results: There were 222 cases, including 100 cases of stable angina, 44 cases of unstable angina and 78 cases of acute myocardial infarction, and 222 controls. The median ages of cases and controls were 62 and 57 years old. The results of multivariate logistic regression analysis showed that serum TAFI>22.88 μg/mL ( P75 of controls ) was associated with the risk of CHD ( OR=1.619, 95%CI: 1.011-2.593 ), unstable angina ( OR=2.917, 95%CI: 1.433-5.939 ) and acute myocardial infarction ( OR=2.626, 95%CI: 1.007-6.847 ). Conclusion The high level of TAFI is related to CHD, unstable angina and acute myocardial infarction.

Objective To express a recombinant protein TFPR1 ( the functional region of the snake venom proteins from Trimeresurus flavoviridis) in Pichia pastoris expression system. Methods The target gene was codon-optimized and synthesized according to the sequence of the conserved structural do-main of triflin and then cloned into the Pichia pastoris expression vector pPICZαA to construct the recombi-nant expression plasmid pPICZαA-TFPR1. The recombinant plasmid pPICZαA-TFPR1 was electroporated into the yeast strain X33. The transformed strains carrying expression plasmid were screened out with Zeocin and then induced by methanol to express the recombinant protein TFPR1. ELISA was performed for the screening of positive clones. SDS-PAGE and Western blot were used for further identification of the ex-pressed products. Results The recombinant plasmid pPICZαA-TFPR1 was successfully constructed. The recombinant protein TFPR1 was expressed in a secreted form at a molecular weight of 16×103. Conclusion The recombinant protein TFPR1 was successfully expressed in Pichia pastoris expression system, which laid a foundation for further researches on its biological function and application as an adjuvant.

Objective - To analyze the prevalence and influencing factors of work related musculoskeletal disorders (WMSDs) Methods among painters in the manufacturing industry. A total of 639 painters from one shipbuilding enterprise, one automobile manufacturing enterprise and three wooden furniture manufacturing enterprises in Guangdong Province were selected as the research subjects using typical sampling method. The Chinese version of Musculoskeletal Disorders Questionnaire was Results used to investigate the prevalence of WMSDs in the past one year, and the influencing factors were analyzed. The total prevalence rate of WMSDs among painters in the manufacturing industry was 37.4%. The prevalence of WMSDs in different vs vs P industries from high to low was shipbuilding, automobile and furniture manufacturing (50.0% 38.7% 29.0%, <0.01). The prevalence of WMSDs in different parts of the body from high to low was neck, ankle/foot, shoulder, low back, upper back, knee, vs vs vs vs vs vs vs vs P hand/wrist, hip/leg and elbow (20.7% 19.2% 17.4% 15.8% 14.1% 13.8% 13.5% 9.5% 6.6%, <0.01). Multivariate logistic regression analysis results showed that working in uncomfortable postures was a risk factor for neck, ankle/ P P foot and shoulder WMSDs (all <0.01); long time head turning was a risk factor for neck and shoulder WMSDs (both <0.05); P overweight and obesity, and bending and turning frequently at the same time were risk factors for ankle/foot WMSDs (all <0.05); P adequate rest time was a protective factor for neck and ankle/foot WMSDs (both <0.01); participated in physical exercise more P than once a week was a protective factor of neck and shoulder WMSDs in painters (all <0.05), after excluding the influence of Conclusion confounding factors. The prevalence of WMSDs in manufacturing painters was high, and the main body parts E mail 4813545@qq.com E mail wangzhongxu2003@163.com· · 中国职业医学 年 月第 卷第 期 ， ， ， 482 2022 10 49 5 Chin Occup Med October 2022 Vol.49 No.5 involved were neck, ankle/foot and shoulder. The influencing factors include individual factors, poor ergonomics factors and unreasonable work organization.

Objective To determine the distributions of major pathogenic capsular types and in vitro antimicrobial susceptibility of different serotypes of Streptococcus suis isolated from clinically healthy sows in China. Methods Tonsil specimens of clinically healthy sows from 10 different provinces in China were collected, a total of 421 S.suis were isolated. Capsular types of S.suis were decided using the sera agglutination reaction. Antimicrobial susceptibility testing was performed using a broth microdilution method and the differences between serotypes were decided statistically. Results The prevalent capsular types of S.suis isolated from clinically healthy sows were 9(26.6% ), 3 (23.5%) and 7(15.7% ) types, respectively. 7.4% of isolates were confirmed to be S.suis type 2. Overall, differences in antimicrobial susceptibility among serotypes of S. suis were found. By comparison, lower resistance was observed for S.suis type 2 from clinically healthy sows. Conclusion The prevalence of pathogenic S.suis serotypes from clinically healthy sows again indicates S.suis is a conditional pathogenic bacterium. Differential prevention and treatment regimes should be considered according to antimicrobial susceptibility of different serotypes of S.suis.

Objective To analyze the polymorphism(s) or mutation(s) of the granulocyte colony-stim- ulating factor gene (G-CSF,Csf3) and its possible association with the susceptibility to systemic lupus erythe- matosus (SLE).Methods Polymorphism screening was carried out by the polymerase chain reaction-single strand conformation polymorphism method (PCR-SSCP),using DNA from 204 Northern Chinese patients with SLE,459 ethnically matched healthy control,78 patients with other autoimmune diseases.Results It was i- dentified that 4 polymorphisms at position 1869,1205,1931,and 394.The nucleotide sequences of the sample that showed different SSCP patterns and different distribution between SLE and healthy controls were deter- mined by direct sequencing.Only the distribution of the fifth extron of Csf3 (1931) between SLE and controls was different.The frequency of A/G genotype (60.5%) and A allele (53.2%) at position 1931 in patients with SLE was significantly higher than that in healthy controls (51.6% and 45.2%,respectively),whereas,the fre- quency of G/G genotype (16.2%) and G allele (46.8%) in patients with SLE was lower than that in healthy controls (28.9% and 54.8% respectively).Conclusion The results suggest that Csf3 (1931) is significantly associated with the susceptibility to SLE in Northern Chinese patients .Further population and functional stud- ies will be followed to establish Csf3 (1931) as one of the susceptible genes for SLE.

PURPOSE: The aim of this study was to establish an in vitro method to purify human multipotent adult progenitor cells (hMAPCs) and assess their possible differentiation into hepatocytes by coculture with human hepatocyte line L02. METHODS: hMAPCs were isolated by magnetic activated cell sorting (MACS) depletion selection using CD45 and GlyA microbeads. After indirect or direct coculture of hMAPCs and human hepatocyte line L02, the expression of albumin (ALB), alpha-fetoprotein (AFP), cytokeratin (CK) 18, and CK19 by hMAPCs was detected by immunocytochemistry. RESULTS: With the MACS method, (5-10) x 10(4)/mL hMAPCs could be separated from 1 x 10(6)/mL bone marrow mononuclear cells. The purity of CD45-/GlyA- cells separated from bone marrow adherent cells was more than 98%, as determined by flow cytometry. In the coculture without cell-to-cell contact, hMAPCs expressed high AFP on day 1, and then tapered daily to low expression on day 7; ALB expression reached its peak on day 5, and remained high on day 7; CK18 was initially expressed on day 5 and was higher on day 7; CK19 was negative in all assays. In the coculture with cell-to-cell contact, ALB and CK18 were expressed by most cells while AFP appeared in only a few on day 5. CONCLUSION: hMAPCs were induced to differentiate into mature hepatocyte-like cells by coculture with a hepatocyte cell line, either with or without cell-to-cell contact, but the former seemed more effective.
Adult* ; alpha-Fetoproteins ; Bone Marrow ; Cell Differentiation ; Cell Line ; Coculture Techniques* ; Flow Cytometry ; Hepatocytes* ; Humans ; Immunohistochemistry ; Keratins ; Microspheres ; Stem Cells*

AIMTo study the effect of 3,4-oxo-isopropylidene-shikimic acid (ISA) on H2O2 (200 mol.L-1, 4 h) injured human umbilical vein endothelial cells (HUVEC).

METHODSMorphological change was observed under microscop. Cell viability was assessed by MTT assay. The release of intracellular lactate dehydrogenase (LDH) and NO was assessed by colorimetry. Radioimmunoassay was used to assess 6-keto-prostaglandin F1 alpha (6-keto-PGF1 alpha).

RESULTSPretreatment with ISA for 6 h alleviated the morphological damage of H2O2 induced HUVECs. At the concentration of 1-100 mumol.L-1, ISA prevented the inhibitory effect on cell viability induced by H2O2 in dose-dependent manner, but increased the ratio of cell viability from 60.4% to 84.3%. ISA reduced LDH release and increased the level of NO and 6-keto-PGF1 alpha in H2O2 induced HUVECs.

CONCLUSIONISA exerted protective effect on H2O2 injured HUVEC.

6-Ketoprostaglandin F1 alpha ; metabolism ; Cell Survival ; drug effects ; Cells, Cultured ; Endothelial Cells ; metabolism ; pathology ; Humans ; Hydrogen Peroxide ; antagonists & inhibitors ; Infant, Newborn ; L-Lactate Dehydrogenase ; metabolism ; Nitric Oxide ; metabolism ; Protective Agents ; pharmacology ; Shikimic Acid ; analogs & derivatives ; pharmacology ; Umbilical Veins ; cytology

This study was aimed to investigate the effects of ouabain at low concentrations on growth regulation in various leukemia cell lines and to determine the therapeutic potential of ouabain in leukemia. By using MTT, flow cytometry (FCM), the changes in cell growth and cell cycle of leukemia cell lines were observed after treating with ouabain at low concentrations ( Cell Line, Tumor ; Cell Proliferation ; drug effects ; Dose-Response Relationship, Drug ; Humans ; Leukemia ; pathology ; Leukemia, Megakaryoblastic, Acute ; pathology ; Ouabain ; pharmacology ; Sodium-Potassium-Exchanging ATPase ; metabolism