AIM:To investigate the effect of fenbendazole (FBZ) on the proliferation of human chronic myelogenous leukemia (CML) cell line K562.METHODS:The CCK-8 assay was used to detect the effect of FBZ on viability of the K562 cells and normal peripheral blood mononuclear cells (PBMC).The cell growth was measured by the method of Trypan blue exclusion.The cell cycle was analyzed by flow cytometry.The cell cycle-related proteins were detected by Western blot.RESULTS:The growth of K562 was significantly inhibited by FBZ.However, it elicited little cytotoxic effect on PBMC.Furthermore, FBZ induced G2/M phase arrest and mitotic catastrophe in the K562 cells based on the changes of nuclear morphology, DNA content, mitotic marker analysis and the number of polykaryocytes.CONCLUSION:Fenbendazole significantly inhibits the proliferation of K562 cells and induces cell cycle arrest at G2/M phase by the regulation of cell cycle-related proteins.

To detect cadmium ions, we constructed a specific microbial sensor and screened detecting cassettes and different fluorescence proteins. Blue fluorescence protein mTagBFP2 was selected as a reporter and a double-promoters model was used in the construction of the fusion reporter vector Pmer::merR-m-Pmer::mTagBFP2-pMD19-T. The reporter vector was then transformed into Escherichia coli MC4100 wild type strain. The medium, incubation time, initial density for induction, and the optimal detection range were determined. The specificity of the biosensor was also checked. The biosensor responded specifically to cadmium irons with low background, and the linear concentration range detection ranged from 0.1 to 75 μmol/L at the initial OD600 = 0.1 with 2 h incubation in IHMM medium. Thus we successfully constructed a specific biosensor to detect cadmium irons and provided useful strategies for development and optimization of microbial sensors to detect heavy metals.
Biosensing Techniques ; Cadmium ; analysis ; Escherichia coli ; Genetic Vectors ; Promoter Regions, Genetic

In this study we used two types of cell cultures, i.e., anchorage-dependent basket and full suspension batch cultures of sTNFRII-gAD-expressing CHO cells in the CelliGen 310 bioreactor (7.5 L) to compare their yields in order to optimize the culturing conditions for efficient expression of sTNFRII-gAD fusion protein consisting of soluble tumor necrosis factor receptor II and globular domain of adiponectin. The anchorage-dependent basket culture was performed in 4L 10% serum-containing medium with the final inoculating concentration of 3 x 10(5) to 4 x 10(5) cells/mL of sTNFRII-gAD-expressing CHO cells for 3 days, and then switched to 4 L serum-free LK021 medium to continue the culture for 4 days. The full suspension batch culture was carried out in the 4 L serum-free LK021 medium with the final inoculating concentration of 3 x 10(5) to 4 x 10(5) cells/mL of sTNFRII-gAD-expressing CHO cells for 7 days. The culturing conditions were monitored in real-time to maintain pH and dissolved oxygen stability through the whole process. The supernatants were collected by centrifuge, and the protein was concentrated through Pellicon flow ultrafiltration system and then purified by DEAE anion exchange. The results showed that the yields of sTNFRII-gAD fusion protein were 8.0 mg/L with 95% purity and 7.5 mg/L with 98% purity in the anchorage-dependent basket and the full suspension batch cultures, respectively. The study provided the framework for the pilot production of sTNFRII-gAD fusion protein.
Adiponectin ; biosynthesis ; genetics ; Animals ; Bioreactors ; CHO Cells ; Cell Culture Techniques ; methods ; Cricetinae ; Cricetulus ; Receptors, Tumor Necrosis Factor, Type II ; biosynthesis ; genetics ; Recombinant Fusion Proteins ; biosynthesis ; genetics

Objective To assess the relationship between mitochondrial DNA (mtDNA) ND2 gene C5178A polymorphism and complications of cardio-cerebral-vascular in patients with type 2 diabetes mellitus (T2DM).Methods This is a case-control study.448 unrelated patients with T2DM were collected from Zhejiang Provincial People's Hospital from 2010 to 2011,including 274 males and 174 females.Direct nucleotide sequencing analysis was used to screen mtDNA ND2 gene C5178A genotyping in ）patients.Meanwhile,detailed clinical and laboratory information for all of study subjects were collected.Body mass index (BMI),blood pressure,blood lipid,blood glucose and incidence rate of cerebral infarction were compared between 5178C patients and 5178A patients.Furthermore,according to the genotyping results,we 2analyzed whether these differences exist in patients with different gender by using t test or x2 test.Results 348 out of 448 patients with T2DM were C carriers and the remaining patients were A carriers.There're significant differences between T2DM patients with 5178A and T2DM patients with 5178C on systolic pressure (124.6 mm Hg ± 9.0 mm Hg vs 127.8 mm Hg ± 10.7 mm Hg,t =2.700,P =0.007)and HDL (1.3 mmol/L ± 0.2 mmol/L vs 1.2 mmol/L ± 0.3 mmol/L,t =2.968,P =0.003).Moreover,the incidence of cerebral infarction in T2DM patients with 5178A (8.0％,8/100) was much lower than that with 5178C (21.0％,73/348 ; x2 =8.832,P =0.003).No statistical gender difference was found in the distribution of C5178A (P ＞ 0.05).Our results also revealed that the female T2DM patients with 5178A had a lower serum triglyceride (1.5 mmol/L ±0.8 mmol/L; t =2.601,P =0.011) and lower systolic pressure (123.6 mm Hg±6.6 mm Hg; t =2.887,P =0.004) than that with 5178C (1.8 mmol/L ± 1.0 mmol/L and 128.0 mm Hg ± 9.0 mm Hg,respectively).Furthermore,cerebral infarction was more common in female T2DM patients with 5178C (21.3％,29/136; x2 =5.232,P =0.022) than that with 5178A (5.3％,2/38).Similarly,male T2DM patients with 5178A had a much lower incidence rate of cerebral infarction (9.7％,6/62; x2 =3.946,P =0.047) than that with 5178C (20.7％,44/212).In contrary,the serum concentration of HDL was higher in male T2DM patients with 5178A (1.4 mmol/L ±0.2 mmol/L;t=3.511,P =0.001) than that with 5178C (1.2 mmol/L±0.3 mmol/L).Conclusions The polymorphism site mtDNA C5178A correlates with cerebral-cardiovascular complications in patients with type 2 diabetes mellitus.mtDNA 5178A allele may protect T2DM patients from developing cerebral-cardiovascular diseases through regulation of blood pressure and lipid metabolism.

Objective To investigate the therapeutic effect of tumor necrosis factor (TNF)-αsiRNA on typeⅡcolla-gen induced arthritis (CIA) in rats. Methods The expression vectors of siRNA against TNF-αgene were constructed suc-cessfully and were injected by tail veil into CIA rats. Twenty-four CIA rats were randomly divided into 4 groups including model group, empty vector group, TNF-α-siRNA1 group and TNF-α-siRNA2 group. CIA rats were injected with the same dose of phosphate buffered sodium (PBS) and pGFP-V-RS vector respectively in model group and empty vector group, while TNF-α-siRNA1 group and TNF-α-siRNA2 group were injected with TNF-α-siRNA1 eukaryotic expression vector and TNF-α-siRNA2 eukaryotic expression vector respectively. Another 6 rats, which were not established CIA model, were in-jected with PBS (blank control group). The serum expression levels of IL-1 were detected by ELISA on day 1, 5, 9 and 13 af-ter injection. The expression level of TNF-αmRNA was detected by reverse transcriptase polymerase chain reaction (RT-PCR) on day 13. Results The expression level of IL-1 was significantly higher on day 1, 5, 9 and 13 in model group than that of blank group (P＜0.05). The expression levels of IL-1 were significantly lower on day 1, 5 and 9 in TNF-α-siRNA1 group and TNF-α-siRNA2 group than that of model group and blank group (P ＜ 0.05). The expression level of TNF-αmRNA was significantly higher on day 13 in model group than that of blank group (P＜0.05). The expression levels of TNF-αmRNA were significantly lower in TNF-α-siRNA1 group and TNF-α-siRNA2 group than those of model group and emp-ty vector group (P＜0.05). Conclusion TNF-αspecific siRNA can suppress the levels of TNF-αmRNA and IL-1, which provides experimental basis for gene therapy of rheumatoid arthritis.

BACKGROUND:The reported time of bone marrow mesenchymal stem cel s induced to differentiate into chondrocytes is different. Few studies have observed and compared the cel s’ dynamic transformation during the induction process.
OBJECTIVE:To observe the dynamic differentiation and the mature time of rabbit bone marrow mesenchymal stem cel s which were directional y induced to chondroblasts for 8, 11, 14, 17, 20 days.
METHODS:Bone marrow was aspirated from the femur of New Zeal rabbits, and bone marrow mesenchymal stem cel s were isolated by gradient centrifugation. After cultivation and amplification, bone marrow mesenchymal stem cel s at passage 3 were directional y induced to chondrocytes by the serum-free medium containing transforming growth factor beta-1. The experiments were divided into five groups according to different induction time points:8 days, 11 days, 14 days, 17 days, 20 days. Then cel ular morphology, toluidine blue staining, typeⅡ col agen immunohistochemistry, aggrecan content in induction medium, and chondrogenic differentiation in each group were observed and compared.
RESULTS AND CONCLUSION:Bone marrow mesenchymal stem cel s had apparently transformed in morphology at 8 days of induction, and presented obvious chondrocytes’ morphology at 14 days. The aggrecan in induction medium could be detected at a low level at 4 days, significantly increased at 8 days, and maintained slow increasing at 20 days. At 14 days, the metachromatic particles could be found by toluidine blue staining, and the col agen type Ⅱimmunohistochemistry was significantly positive in cel climbing slice. Experimental findings indicate that, bone marrow mesenchymal stem cel s that are monolayer cultured in a high density can be induced into chondroblasts at the effect of transforming growth factor beta-1 and other factors. There are a few chondroblasts in the early induction process, then cel s begin to have chondrocytes morphology and function after induced for 8 days, and may differentiate to mature chondrocytes at 14 days. In addition, they can keep a high biological activity in the induction process.

Objective To establish a method for detection of gene mutations in β-thalassemia by high-resolution melting (HRM) and study its preliminary clinical application.Methods Two common mutations [ IVS-2-654 ( C ＞ T ) and -28 ( A ＞ G ) ]of β-thalassemia in Wenzhou city population were selected.The plasmid DNA fragments of these mutations were constructed by TA clone technology as PCR templates or genotyping controls.A method for detection of β-thalassemia gene mutations based on HRM analysis was established and its specificity,sensitivity and repeatability were methodologically evaluated.One hundred and seventeen patients with clinically suspected β-thalassemia from Second Affiliated Hospital and Yu ying Children's Hospital of Wenzhou Medical College were enrolled into this study.The genomic DNA was extracted from whole blood cells and detected by HRM method.The results were compared with the direct sequencing data.Results HRM method could detect the mutations [ IVS-2-654( C ＞ T) and -28 ( A ＞ G ) ]of β-thalassemia and the results did not show any non-specific amplified fragments.All within-run and between-run coefficients of variation for different DNA types' Tm were smaller than 0.1％.And minimum 103 copies of DNA of each assay and 10％ mutation could be determined by this method.One hundred and seventeen patients with clinically suspected β-thalassemia were detected with HRM and all the results were in accordance with direct DNA sequencing.There were 45 IVS-2-654 ( C ＞ T)heterozygous mutation and 9-28 ( A ＞ G)heterozygous mutation and none homozygous mutation.Conclusion The method of rapid identification of β-thalassemia gene mutations based on HRM analysis is successfully established,which is a convenient,rapid,specific,sensitive and accurate technique for screening gene mutations in β-thalassemia as well as a general technical platform to identify other gene mutations.

Objective To prepare hepatocyte growth factor(HGF) recombinant protein and confirm its activity preliminarily according to building HGF gene prokaryotic expression vector and transforming into E.coli.Methods Clone HGF inserted into the vector pET-26b(+) to construct prokaryotic expression vector pET-26b(+)-HGF and transform into E.coli Rosseta(DE3).The transformed bacteria induced by IPTG was purified through Ni-NTA resin affinity chromatography frozen-drying after renaturation.Results HGF gene recombinant prokaryotic expression vector pET-26b(+)-HGF was constructed successfully.E.coli Rosseta(DE3) which was transformed into pET-26b(+)-HGF expresses the target protein as the form of inclusion bodies,accounting for 38％ of the total bacterial proteins,and confirmed by Western blot.HGF protein which was purified by Ni-NTA resin affinity chromatography,has a purity of about 95％,and can promote proliferation,migration,and inhibition of apoptosis for human non-small cell lung cancer cell line A549 cells after interaction.Conclusion HGF gene recombinant prokaryotic expression vector pET-26b (+)-HGF was constructed and expressed in transformed E.coli Rosseta(DE3) successfully.They resumed their recombinant HGF protein structure after purification and renaturation,and had biological activity confirmed by in vitro studies.

Objective To prenatally diagnose HA fetus with different clinical backgrounds. Methods Genetic tests were performed on 15 gravidas subjected for prenatal diagnosis of HA and different methods were employed for diagnosis according to the gestational weeks and clinical data. Amniotic fluid were taken from pregnant women within 23 gestational weeks for direct genotyping and indirect linkage analysis, since these women had probands with clear-cut mutations. Cordocentesis was performed for linkage analysis in pregnant women over 23 gestational weeks with probands whose types of mutation were unknown, while the FⅧ activity tests were carried out simultaneously. For the pregnant women over 23 gestational weeks without proband, cordocentesis was operated for measurement of FⅧ activity and karyotyping, but carriers of hemophilia A could not be detected in these cases. The introns 22 and 1 inversion of F8 gene were identified by long distance-polymerase chain reaction. Nucleotide sequencing was employed if the gene inversion could not be found and linkage analysis of 7 polymorphic markers, including DXS1108, F8Civs13, INTRON22,DXS1073,DXS9901, DXS15, DXS8069 and sex site (Amelo) were applied eventually. Identification of maternal blood contamination must be done before the tests. Results Fifteen samples were identified without maternal blood contamination. Five fetuses were diagnosed with hemophilia A. Meanwhile there were three pregnant women whose cord blood FⅧ activities were less than 1%. One of them was accompanied by trisomy 21; another had inversion mutation in introns 22 of F8 gene; the remaining one was identified with missense mutation in exon 23 (p. Arg2182Cys) of F8 gene. Conclusions Diverse methods should be applied in prenatal diagnosis of hemophilia A with different clinical backgrounds, for the sake of birth defects prevention.

Objective To develop and evaluate an aptamer based biosensor (aptasensor) for rapid colorimetric detection of enteropathogenic Escherichia coli (EPEC). Method The aptasensor was fabricated by modifying the truncated LPS-binding aptamer on the surface of nanoscale polydiacetylene vesicles using peptide bonding between the carboxyl group of the vesicle and the amine group of the aptamer. Molecular recognition between EPEC and aptamer at the interface of the vesicle led to blue-red transition of polydiacetylene which was readily visible to the naked eyes and could be quantified by colorimetric responses (CR). Transmission electron microscopy (TEM) was used to confirm the specific interactions between EPEC and polydiacetylene vesicles. Result Truncated aptamer showed the similar LPS-binding activity. The aptasensor could detect the target bacteria in a range of 105-108 colony-forming units (CFU)/ml within less than 30 minutes and its specificity was 100% for detection of EPEC O111. The sensor reproducibiliry obtained at 106 CFU/ml was 6. 08% R. S. D. The results of TEM confirmed that the specific interactions between EPEC and polydiacetylene vesicles. Conclusion A new aptasensor was developed successfully for rapid colorimetric detection of EPEC.