Objective To explore the relationship between drug resistance of leukemic cells and Caspase-3,this study took adriamycin(ADR)-resistant human chronic granulocytic leukemic cell strain K562/AO_2 as research subject,observing the cell survival and the morphological change of cell apoptosis under the action of ADR and arsenic sulfide and the Caspase-3 activity before and after putting in the Caspase-3 inhibitor.Methods ① The 3-(4,5-dimethylthiazo-2-yl)-2,5-diphenyl-tetrazolium bromide(MTT) method was used to determine the cell survival(A value) of K562/AO_(2)cell strain under the action of ADR and arsenic sulfide.② DNA agarose gel electrophoresis was performed to observe the DNA cleavage of apoptotic cells.③ The enzyme colorimetric activity assay(CAA) method was used to measure the change of the Caspase-3 activity of K562/AO_(2) cell strain.Results ① The A value of K562/AO_(2) cells had a time and dosage dependent relation with arsenic sulfide.② Apoptosis occurred in the K562/AO_(2) cell strain affected by arsenic sulfide.③ Compared with the cell strains with the Caspase-3 inhibitor added,the Caspase-3 activity of those without the Caspase-3 inhibitor increased remarkably(P

Objective To observe the effects of chemo-endocrine therapy on gastric carcinoma (GC). Methods Cancerous tissues from 95 patients with primary GC were examined for the presence of estrogen receptor (ER) and progesterone receptor (PgR). Afterwards, 64 GC patients with recurrent or metastatic conditions were randomly divided into two groups: chemotherapy group and chemo-endocrine therapy group. Results A total of 34.38% ER positive and 16.30% PgR positive rates were found. For ER positive patients, the use of tamoxifen-EAP regimens was more effective than that of EAP alone (P

Objective: To analyze the gene mutations and clinical features of patients with Noonan syndrome and hypertrophic cardiomyopathy. Method: Determined the mutation domain in five cases diagnosed with Noonan syndrome and hypertrophic cardiomyopathy and identified the relationship between the mutant domain and hypertrophic cardiomyopathy by searching relevant articles in pubmed database. Result: Three mutant genes (PTPN11 gene in chromosome 12, RIT1 gene in chromosome 1 and RAF1 gene in chromosome 3) in five cases all had been reported to be related to hypertrophic cardiomyopathy. The reported hypertrophic cardiomyopathy relevant genes MYPN, MYH6 and MYBP3 had also been found in case 1 and 2. Patients with same gene mutation had different clinical manifestations. Both case 4 and 5 had RAF1 mutation (c.770C>T). However, case 4 had special face, low IQ, mild pulmonary artery stenosis, and only mild ventricular hypertrophy. Conclusion Noonan syndrome is a genetic heterogeneity disease. Our study identified specific gene mutations that could result in Noonan syndrome with hypertrophic cardiomyopathy through molecular biology methods. The results emphasize the importance of gene detection in the management of Noonan syndrome.

β-glucosidase has important applications in food, medicine, biomass conversion and other fields. Therefore, exploring β-glucosidase with strong stability and excellent properties is a research hotspot. In this study, a GH3 family β-glucosidase gene named Iubgl3 was successfully cloned from Infirmifilum uzonense. Sequence analysis showed that the full length of Iubgl3 was 2 106 bp, encoding 702 amino acids, with a theoretical molecular weight of 77.0 kDa. The gene was cloned and expressed in E. coli and the enzymatic properties of purified IuBgl3 were studied. The results showed that the optimal pH and temperature for pNPG hydrolysis were 5.0 and 85 ℃, respectively. The enzyme has good thermal stability, and more than 85% of enzyme activity can be retained after being treated at 80 ℃ for2 h. This enzyme has good pH stability and more than 85% of its activity can be retained after being treated at pH 4.0-11.0 for 1 h. It was found that the enzyme had high hydrolysis ability to p-nitrophenyl β-d-glucoside (pNPG) and p-nitrophenyl β-d-xylopyranoside (pNPX). When pNPG was used as the substrate, the kinetic parameters K_m and V_max were 0.38 mmol and 248.55 μmol/(mg·min), respectively, and the catalytic efficiency k_cat/K_m was 6 149.20 s^-1mmol^-1. Most metal ions had no significant effect on the enzyme activity of IuBgl3. SDS completely inactivated the enzyme, while EDTA increased the enzyme activity by 30%. This study expanded the β-glucosidase gene diversity of the thermophilic archaea GH3 family and obtained a thermostable acid bifunctional enzyme with good industrial application potential.
beta-Glucosidase/chemistry* ; Archaea/metabolism* ; Escherichia coli/metabolism* ; Hydrogen-Ion Concentration ; Temperature ; Glucosides ; Enzyme Stability ; Substrate Specificity ; Kinetics

β-glucosidase has important applications in food, pharmaceutics, biomass conversion and other fields, exploring β-glucosidase with strong adaptability and excellent properties thus has received extensive interest. In this study, a novel glucosidase from the GH1 family derived from Cuniculiplasma divulgatum was cloned, expressed, and characterized, aiming to find a better β-glucosidase. The amino acid sequences of GH1 family glucosidase derived from C. divulgatum were obtained from the NCBI database, and a recombinant plasmid pET-30a(+)-CdBglA was constructed. The recombinant protein was induced to express in Escherichia coli BL21(DE3). The enzymatic properties of the purified CdBglA were studied. The molecular weight of the recombinant CdBglA was 56.0 kDa. The optimum pH and temperature were 5.5 and 55 ℃, respectively. The enzyme showed good pH stability, 92.33% of the initial activity could be retained when treated under pH 5.5-11.0 for 1 h. When pNPG was used as a substrate, the kinetic parameters K_m, V_max and K_cat/K_m were 0.81 mmol, 291.99 μmol/(mg·min), and 387.50 s^-1 mmol^-1, respectively. 90.33% of the initial enzyme activity could be retained when CdBglA was placed with various heavy metal ions at a final concentration of 5 mmol/L. The enzyme activity was increased by 28.67% under 15% ethanol solution, remained unchanged under 20% ethanol, and 43.68% of the enzyme activity could still be retained under 30% ethanol. The enzyme has an obvious activation effect at 0-1.5 mol/L NaCl and can tolerate 0.8 mol/L glucose. In conclusion, CdBglA is an acidic and mesophilic enzyme with broad pH stability and strong tolerance to most metal ions, organic solvents, NaCl and glucose. These characteristics may facilitate future theoretical research and industrial production.
beta-Glucosidase ; Sodium Chloride ; Temperature ; Glucose ; Ethanol/chemistry* ; Ions ; Hydrogen-Ion Concentration ; Enzyme Stability ; Substrate Specificity