Objective To investigate the effect of As2 O3 in combination with cinobufacini on proliferation and apoptosis of the K562 cells and provide theoretical basis for clinical application.Methods Cell proliferation was assayed by analyzing the growth and viability of the cells.Apoptosis was assayed by performing cell morphology,Annexin-V/PI staining,DNA-PI staining,and DNA gel electrophoresis.Results After exposure to As2O3 and cinobufacini,the growth of K562 cells was inhibited and the viability of K562 cells was decreased. After treated with 1.0μmol/L As2O3,0.125μg/ml cinobufacini,0.25μg/ml cinobufacini,1.0μmol/L As2O3 + 0.125 μg/ml cinobufacini,1.0μmol/L As2O3 + 0.25μg/ml cinobufacini for 24 and 48 hours,the proliferation inhibition rate were(24 ± 1.3)%,(21 ± 1.5)%,(38 ± 3.1)%,(57 ±2.7)%,(66 ±3.3)% and(49 ±2.9)%,(48 ±2.7)%,(61 ±2.1)%,(77 ±3.8)%,(82 ±4.2)%,the apoptosis rate of K562 cells were(4.8 ± 0.5)%,(5.6 ± 0.7)%,(9.8 ± 0.6)%,(11.9 ± 1.2)%,(15.2±1.5)% and(11.0 ±0.9)%,(12.9 ±1.1)%,(18.4 ±1.5)%,(21.0 ±2.0)%,(28.0 ±1.9)%.The percentage of apoptotic cells was a time- and dose-dependent manner.Typical DNA ladder was shown by DNA gel electrophoresis.Conclusions As2O3 combined with cinobufacini inhibited the proliferation of K562 cells and induced apoptosis of the K562 cells,the combination of the two drugs had better effect.

Objective To investigate the change of T helper 17 cells (Th17) in the peripheral blood mononuclear cell (PBMC) in patients with liver cystic echinococcosis. Methods Fifty-six subjects were divided into three groups: healthy controls (HD, n = 20), patients with cystic echinococcosis (CE, n= 18) and patients with cystic echinococcosis combined with bile fistula (BF,n= 18). The frequency of Th17 cells in CD4+ T lymphocytes was detected by flow cytometry. Th17-related cytokines including interleukin (IL)-17 and IL-23 were measured by enzyme-linked immunosorbent assay (ELISA). The data were analyzed by t test and Pearson correlation analysis.Results The frequency of Th17 in the peripheral blood was significantly lower in CE group compared to BF group and HD group [(0. 23±0. 11)% vs (0. 76±0.43)% vs (0.52±0.50)%; t=2. 225 and4. 077 respectively, both P＜0.05), while there was no statistical difference between BF group and HD group (t=1. 931, P＞0.05). The levels IL-17 and IL-23 were (12.1±3.7) ng/L and (84.4±46.0) ng/L respectively in CE group, which were lower than those in BF group [(15.5±4.1) ng/L and (138.6±37. 9) ng/L, respectively; t=2. 515 and 3. 649 respectively, both P＜0.05] and those in HD group [(14.8±4.4) ng/L and (138.1±48. 7) ng/L, respectively; t=2. 401 and 3. 706 respectively,both P ＜0.05], while there was no statistical difference between BF group and HD group (t=0. 534,P ＞0.05). Serum concentrations of IL-17 were all positively correlated with the concentrations of IL23 in these three groups (r=0. 657, P＜0.05). Conclusion The frequeny of Th17 cells in PBMC and the serum concentrations of IL-17, IL-23 are significantly reduced in patients with cystic echinococcosis.

Objective To investigate the effect of before and after combination therapy of thalidomide and methotrexate (T+M) on regulatory T cells and IL-6 expression profile,and to reveal the mechanism of therapeutic effect of T+M on rheumatoid arthritis.Methods A total of 58 patients with rheumatoid arthritis from August 2014 to August 2016 in the Third Affiliated Hospital of Wenzhou Medical University.The flow cytometry assay and enzyme-linked immunosorbent assay (ELISA) were used to estimate the ratio of peripheral blood regulatory T cells and expression profile of IL-6 in peripheral blood lymphocyte before and after combination therapy of thalidomide and methotrexate .Results After combination therapy of T+M,the ratio of peripheral blood CD25 +Foxp3/CD4 +T cells had a marked increase compared with before combination of therapy of T +M;but the expression of IL-6 had a significant decrease in the group of after combination therapy of T +M compared with before combination therapy.Conclusion The effect of combination therapy of T+M on rheumatoid arthritis is associated with increasing the ratio of regulatory T cells and decreasing the secretion of IL-6 that could regulate T cells to homeostasis.

COVID-19 has swept globally and Pakistan is no exception.To investigate the initial introductions and transmissions of the SARS-CoV-2 in Pakistan,we performed the largest genomic epidemiology study of COVID-19 in Pakistan and generated 150 complete SARS-CoV-2 genome sequences from samples collected from March 16 to June 1,2020.We identified a total of 347 mutated positions,31 of which were over-represented in Pakistan.Meanwhile,we found over 1000 intra-host single-nucleotide variants(iSNVs).Several of them occurred concurrently,indicating possible interactions among them or coevolution.Some of the high-frequency iSNVs in Pakistan were not observed in the global population,suggesting strong purifying selections.The genomic epidemiology revealed five distinctive spreading clusters.The largest cluster consisted of 74 viruses which were derived from different geographic locations of Pakistan and formed a deep hierarchical structure,indicating an extensive and persistent nation-wide transmission of the virus that was probably attributed to a signature mutation(G8371T in ORF 1ab)of this cluster.Further-more,28 putative international introductions were identified,several of which are consistent with the epidemiological investigations.In all,this study has inferred the possible pathways of introduc-tions and transmissions of SARS-CoV-2 in Pakistan,which could aid ongoing and future viral surveillance and COVID-19 control.