Recombinant Schistosoma japonicum egg ribonuclease SjCP1412 inhibits the activation of LX-2 hepatic stellate cells in vitro / 中国血吸虫病防治杂志

Objective To investigate the effect of recombinant Schistosoma japonicum egg ribonuclease SjCP1412 (rSjCP1412) on proliferation, cell cycle, apoptosis and activation of human hepatic stellate cells LX-2 in vitro, and explore the underlying mechanisms. Methods The rSjCP1412 protein was expressed in Escherichia coli BL21 by prokaryotic expression, and the highly purified soluble rSjCP1412 protein was prepared by Ni NTA affinity chromatography and urea gradient refolding dialysis. Yeast RNA was digested using 12.5, 25.0, 50.0 µg rSjCP1412 proteins at 37 °C for 2, 3, 4 h, and the enzymatic products were electrophoresed on 1.5% agarose gel to observe the RNAase activity of rSjCP1412 protein. The proliferation of LX-2 cells stimulated by different doses of rSjCP1412 protein for 48 hours was measured using CCK-8 assay, and the apoptosis of LX-2 cells stimulated by different doses of rSjCP1412 protein for 48 hours was detected using the Annexin V-FITC/PI double staining, while the percentage of LX-2 cells at G0/G1, S and G2/M phases of cell cycle following stimulation with different doses of rSjCP1412 protein for 48 h was detected by DAPI staining. The type I collagen, type III collagen and α-smooth muscle actin (α-SMA) mRNA expression was quantified using quantitative florescent real-time PCR (qPCR) assay and Western blotting at transcriptional and translational levels in LX-2 cells following stimulation with different doses of rSjCP1412 protein for 48 h, while soluble egg antigen (SEA) served a positive control and PBS without rSjCP1412 protein as a normal control in the above experiments. The expression of collagen I, α-SMA and Smad4 protein was determined using Western blotting in LX-2 cells following stimulation with rSjCP1412 protein, transforming growth factor-β1 (TGF-β1) alone or in combination, to examine the signaling for the effect of rSjCP1412 protein on LX-2 cells. Results The rSjCP1412 protein was successfully expressed and the highly purified soluble rSjCP1412 protein was prepared, which had a RNase activity. Compared with the normal group, the survival rates of LX-2 cells significantly decreased post-treatment with 12.5, 25.0, 50.0 µg/mL rSjCP1412 protein and SEA for 48 h (F = 22.417 and 20.448, both P values < 0.05). The apoptotic rates of LX-2 cells significantly increased post-treatment with 12.5, 25.0, 50.0 µg/mL rSjCP1412 protein for 48 h (F = 11.350, P < 0.05), and treatment with 12.5, 25.0, 50.0 µg/mL rSjCP1412 protein for 48 h resulted in arrest of LX-2 cells in G0/G1 phase (F = 20.710, P < 0.05). Treatment with 12.5, 25.0, 50.0 µg/mL rSjCP1412 protein for 48 h caused a significant reduction in relative expression levels of collagen I (F = 11.340, P < 0.05), collagen III (F = 456.600, P < 0.05) and α-SMA mRNA (F = 23.100, P < 0.05) in LX-2 cells, and both rSjCP1412 protein and SEA treatment caused a significant reduction in collagen I (F = 1 302.000, P < 0.05), α-SMA (F = 49.750, P < 0.05) and Smad4 protein expression (F = 52.420, P < 0.05) in LX-2 cells. In addition, rSjCP1412 protein treatment inhibited collagen I (F = 66.290, P < 0.05), α-SMA (F = 31.300, P < 0.05) and Smad4 protein expression (F = 27.010, P < 0.05) in LX-2 cells activated by TGF-β1. Conclusion rSjCP1412 protein may induce apoptosis of LX-2 cells and inhibit proliferation, cell cycle and activation of LX-2 cells through down-regulating Smad4 signaling molecules.

Effects of miR-363-5p on proliferation and apoptosis of nasopharyngeal carcinoma cells and the possible mechanism / 中国基层医药

Objective:To investigate the effects of miR-363-5p on the proliferation and apoptosis of nasopharyngeal carcinoma cells and the possible mechanism.Methods:miR-363-5p expression in human normal nasopharyngeal epithelial cells NP-69 and nasopharyngeal carcinoma cells 5-8F was detected using quantitative real-time polymerase chain reaction. Proliferation and apoptosis of 5-8F cells overexpresing miR-365-5p were determined. At the same time, Caspase3 and BRD4 protein expression in 5-8F cells were also detected.Results:miR-365-5p expression in 5-8F cells (0.71 ± 0.45) was significantly lower than that in NP-69 cells ( t = 2.68, P < 0.05). After overexpressing miR-363-5p, the proliferation of 5-8F cells was significantly decreased ( F = 22.68, P < 0.05). The apoptotic rate in the 5-8F cells was significantly higher than that in the control group [(24.45 ± 5.38)% vs. (18.23 ± 2.41)%, t = 4.13, P < 0.05]. Bax and Caspase3 protein levels in the 5-8F cells were (1.35 ± 0.24) and (1.44 ± 0.34) respectively, which were significantly higher than those in the NP-69 cells [(1.00 ± 0.08), (1.00 ± 0.23), t = 3.12, 5.12, P < 0.05]. BRD4 protein level in the 5-8F cells was significantly lower than that in the control group [(0.42 ± 0.24) vs. (1.00 ± 0.37), t = 2.98, P <0.05]. Conclusion:miR-365-5p can inhibit proliferation of nasopharyngeal carcinoma cells and promote their apoptosis. The negative regulatory effects of miR-363-5p on tumor cells are achieved possibly through inhibiting BRD4 protein expression.

A highly sensitive bio-barcode immunoassay for multi-residue detection of organophosphate pesticides based on fluorescence anti-quenching / 药物分析学报

Balancing the risks and benefits of organophosphate pesticides(OPs)on human and environmental health relies partly on their accurate measurement.A highly sensitive fluorescence anti-quenching multi-residue bio-barcode immunoassay was developed to detect OPs(triazophos,parathion,and chlorpyrifos)in apples,turnips,cabbages,and rice.Gold nanoparticles were functionalized with monoclonal antibodies against the tested OPs.DNA oligonucleotides were complementarily hybridized with an RNA fluorescent label for signal amplification.The detection signals were generated by DNA-RNA hybridization and ribonuclease H dissociation of the fluorophore.The resulting fluorescence signal en-ables multiplexed quantification of triazophos,parathion,and chlorpyrifos residues over the concen-tration range of 0.01-25,0.01-50,and 0.1-50 ng/mL with limits of detection of 0.014,0.011,and 0.126 ng/mL,respectively.The mean recovery ranged between 80.3％and 110.8％with relative standard deviations of 7.3％-17.6％,which correlate well with results obtained by liquid chromatography-tandem mass spectrometry(LC-MS/MS).The proposed bio-barcode immunoassay is stable,reproducible and reliable,and is able to detect low residual levels of multi-residue OPs in agricultural products.

Advances in chemical synthesis of dual inhibitors of HIV integrase and ribonuclease H / 药学学报

Antiretroviral therapy has been used for treating AIDS with 31 single-target anti-HIV drugs currently on market. Searching for safe and effective of novel anti-HIV drugs remains a challenge worldwide. Multi-targets single-structure compounds referred to as designed multiple ligands (DMLs) have become a hot topic of producing anti-HIV drugs recently due to reduction in the likelihood of drug resistance, simplified dosing and improved patient adherence. Integrase (IN) and ribonuclease H (RNase H) are two indispensable enzymes in HIV republication, therefore are two important targets for developing anti-HIV drugs. Recently, diverse dual inhibitors of HIV IN and RNase H (IN/RNase H) have been developed via rational drug design and screening. This review summarizes the advances in chemically synthesized dual inhibitors of HIV IN/RNase H to provide the information for developing multi-targets anti-HIV drugs.

Purification and characterization of two PR-10 protein isoforms from the crude drug of Angelica sinensis / 生物工程学报

Two proteins of similar molecular weight (named as ASPR-C-1 and ASPR-C-2) from the crude drug of Angelica sinensis were purified and characterized by 80% ammonium sulfate precipitation, Sephadex G-50 gel filtration chromatography, and DEAE-Sepharose anion exchange chromatography. The molecular weight of ASPR-C-1 and ASPR-C-2 on SDS-PAGE was 17.33 kDa and 17.18 kDa, respectively. They were mainly monomeric in solution, but partially formed dimers and they were glycoproteins with glycosyl content of 2.6% and 8.2%, respectively. Both ASPR-C-1 and ASPR-C-2 were identified to be members of pathogenesis-related 10 family of proteins by matrix-assisted laser desorption ionization time-of-flight mass spectrometry and have ribonuclease activities with the specific activity of 73.60 U/mg and 146.76 U/mg, respectively. The optimum pH of the two isoforms was similar, at about 5.6, while their optimum temperatures were different. The optimum temperature of ASPR-C-1 was 50 ℃, and that of ASPR-C-2 was 60 ℃. Both isoforms presented highest thermal stability at 60 ℃. However, ASPR-C-2 was more thermotolerant than ASPR-C-1. The latter was rapidly inactivated and retained only about 20% residual activity while the former still maintained about 80% of its original activity at a higher treatment temperature (80 to 100 ℃). In addition, Fe²⁺ had an activating effect on the ribonuclease activities of two isoforms while Ca²⁺, Mg²⁺, Zn²⁺, Mn²⁺, Ag⁺, Cu²⁺, EDTA (Elhylene diamine tetraacetic acid), dithiothreitol and sodium dodecylsulphate showed different degrees of inhibition of the enzyme activities. Our findings provide a foundation for further research on the biological function of PR-10 protein from Angelica sinensis.

Purification and biochemical function of Astragalus membtanaceus pathogenesis-related protein 10 / 中国中药杂志

Astragalus membranaceus pathogenesis-related protein 10 (AmPR-10) is largely expressed in case of environmental pressure and pathogen invasion. This study aims to explore the biochemical functions of AmPR-10. The dried root of Astragalus membranaceus was mechanically homogenized and extracted by Tris-HCl buffer to obtain its crude extract, which was then purified by anion exchange chromatography and gel filtration chromatography to obtain electrophoretically pure AmPR-10. The nuclease activity of AmPR-10 was tested with different RNAs by detecting the absorption value at 260 nm. The results demonstrated potent nuclease activity toward yeast tRNA, yeast RNA, Poly (A) and Poly (C). The optimum reaction temperature was 50 °C and pH was 7-8. EDTA showed no effect on its activity, while Mg²⁺ exhibited potent activation effect on the activity, and Co²⁺, Ca²⁺ and Zn²⁺ manifested moderately inhibition of the activity. Since AmPR-10 had no sequence homology with other known nucleases, AmPR-10 was probably a novel nuclease. The inhibition kinetic data against papain was analyzed by Lineweaver-Burk plots, and the results showed that the inhibition of papain followed noncompetitive-type kinetics. AmPR-10 played an important role in Astragalus membranaceus defense mechanism against environmental pressure and pathogen invasion, which may be achieved by inhibiting cycteine enzymes activity.

Research on purification and activity characterization of AmPR-10 ribonuclease from Astragalus membranaceus / 中草药

Objective To establish a stable and rapid separation and purification method for Astragalus membranaceus (Am) pathogenesis-related protein-10 (AmPR-10) using an automatic intelligent protein purification system AKTA Avant 25, and analyze its physiochemical and biological activity. Methods Am was extracted by Tris-HCl buffer. The crude extract was captured by anion exchange chromatography, and finely separated by hydrophobic chromatography and gel filtration chromatography. The relative molecular weight of AmPR-10 was measured by MALDI-TOF/TOF mass spectrometry, the protein identification was determined by mass spectrometry and MS/MS Ion Search, the glycoprotein identification was estimated by periodic acid-Schiff method, and the ribonuclease activity and effect factors were analyzed by agarose gel electrophoresis. Results The electrophoretically pure AmPR-10 was obtained by three-step purification of Q Sepharose Fast Flow, Butyl Sepharose High Performance and SuperdexTM 75 10/300 GL from the crude extraction. The relative molecular weight of AmPR-10 was 16 801. AmPR-10 was highly homologous to PR-10 and has no carbohydrate chains. Incubated at 56 ℃ for 30 min, AmPR-10 exhibited significant ribonuclease activity to total RNA of mammalian cells. The activity was insensitive to NaCl, pH value and mental ions, and weekly inhibited by 0.5 mol/L NaCl, pH 9.0, Mg2+ and Co2+. The activity was the same at EDTA as high as 20 mmol/L. Conclusion The three-step method of exchange chromatography-hydrophobic chromatography-gel filtration chromatography, a stable and rapid separation and purification method of AmPR-10, can be applied for other Chinese herbs. AmPR-10 might play an important role in resistance against virus.

Aislamiento y caracterizacion parcial de fracciones con actividad ribonucleasa a partir del latex de calotropis procera (Aiton) W.T. Aiton y pedilanthus tithymaloides (L.) poit / Isolation and partial characterization of fractions with ribonuclease activity from latex of calotropis procera (Aiton) W.T. Aiton and pedilanthus tithymaloides (L.) poit

Con el objetivo de aislar y caracterizar parcialmente las enzimas ribonucleasas (RNasas) contenidas en el látex de Calotropis procera y Pedilanthus tithymaloides, se colectaron muestras de plantas adultas. Las proteínas solubles fueron extraídas con acetato de sodio y centrifugación a 16.000 x g durante 15 min y fraccionadas por cromatografía de intercambio iónico. Se estimó la masa molecular a través de ecuaciones de regresión lineal. Se realizaron pruebas de glicosilación. En ambas especies, las proteínas con actividad RNasa presentaron una masa molecular entre 28 y 30 kDa. No existe evidencia de proteínas glicosiladas en el látex de C. procera. En P. tithymaloides la RNasa es una proteína glicosilada.

In order to isolate and characterize partially ribonucleases (RNases) enzymes contained in the latex from Calotropis procera and Pedilanthus tithymaloides, samples were collected from mature plants. Soluble proteins were extracted with sodium acetate and centrifugation at 16,000 xg for 15 min and fractionated by ion exchange chromatography. Molecular mass was estimated by linear regression equations. Glycosylation tests were conducted. In both species, proteins with RNase activity showed a molecular mass between 28 and 30 kDa. No evidence of glycosylated proteins in latex from C. procera. In P. tithymaloides, RNase may be a glycosylated protein.

Over-expression of human ribonuclease inhibitor suppresses invasion and migration of transplanted bladder cancer / 重庆医学

Objective To investigate the effect of over-expression of human ribonuclease inhibitor suppresses invasion and migration of transplanted bladder cancer .Methods The T24 cells were stably transfected with pIRES2-EGFP-RI and pIRES2-EG-FP plasmid respectively .Using the cell transfected with pIRES2-EGFP and untransfected cell as controls .and the positive clones were screened by G418 ,respectively ;Tumor cells of the three groups at 2 × 106 were respectively injected into the back of BALB/C nude mice to establish the xenograft models .Change of micro-blood vessels in tumor tissue and expression of CD31 were detected by Immunohisto-chemical and HE staining .Immunohisto-chemical assay was used to detect the expression of RI ,MMP-2 ,MMP-9 ,E-cadherin ,N-cadherin ,Vimentin ,Snail ,Slug ,Twist in the tumors .Results Animal experiment showed that the T24-RI cells group significantly inhibited the growth of bladder cancer compared with the other two control groups .Compared with the T24 and T24 vector cells groups ,the microvessel density in tumor tissue of T24-RI group was notably reduced and the expressions of MMP-2 , MMP-9 ,N-cadherin ,Vimentin ,Snail ,Slug ,Twist significantly were decreased simultaneously ,while the expressions of RI and E-cadherin were increased .Conclusion up-regulation RI can inhibit the growth of transplanted bladder cancer in nude mice by decrea-sing the expression of invasion protein and EM T protein .

Study on NIH3T3 cells infected by retrovirus encoding EGFP fusion of human ribonuclease inhibitor protein / 中国医学装备

Objective:To identify the expression of egfp-hri fusion on NIH3T3 cells which is carried by recombinant retrovirus. Methods:The egfp-hri fusion gene was integrated intoNIH3T3 cells by the infection of recombinant viral supernatant from the G418 resistent PA317 cells transfected stably with the plasmid of pLNCX-EGFP-C1-hri. The expression effect of egfp-hri fusion was visualized under the fluorescent microscope, while the expression levels of egfp-hri fusion protein by Western blot. Results:The observation from fluorescent microscope showed the green fluorescent was obviously observed in the cytoplasm , western-blotting showed the expression level of egfp-hri fusion gene increased by 83%and 81%, as compared with those uninfected cells and in the cells infected with empty vector, respectively. Conclusion:The infected NIH3T3 cells can express egfp-hri fusion protein successfully.

Identification of the expression of recombinated plasmid pLNCX-EGFP-C1-hri in PA317 packaging cell line / 中国医学装备

Objective:To identify the expression of plasmid pLNCX-EGFP-C1-hri targeting the gene of Human ribonuclease inhibitor (hri) in PA317 cells which is capable of expression in mammalian cells.Methods: The vector of pLNCX-EGFP-C1-hri was transfected into PA317 cells by Lipofectamine 2000 and then the expression of recombinated plasmid was verified in living cells by observing the transcription level of egfp-hri fusion gene mRNA with RT-PCR method and the expression level of egfp-fusion hRI protein with western blotting method respectively.Results: Both RT-PCR and western blotting showed the egfp-hri fusion gene was obviously expression in PA317 cells.Conclusion: The plasmid of pLNCX-EGFP-C1-hri targeting hRI is successfully constructed and the protein of hRI can be expressed in PA317 cells correctly.

Establishment and optimization of a method to extract miRNAs from plasma / 军事医学

Objective To develop and optimize a new method to extract miRNAs from plasma.Methods miRNAs were extracted from plasma by mixing it with the extraction solution that contained surfactant and by heating .Then the ribonuclease inhibitor was added into the extraction to prevent RNAs from degradation .The expression level of each miRNA was detected by real-time quantitative PCR in oder to evaluate the feasibility of this method .Results A method which extracted miRNAs from plamsa in just one step was established .The specificity , reproducibility and stability of this method have been demonstrated by real-time quantitative PCR .Conclusion The one-step method is simple , inexpensive , and plasma-saving.It seems like a new method for clinical examination of miRNAs from plasma .

Target-directed catalytic metallodrugs

Most drugs function by binding reversibly to specific biological targets, and therapeutic effects generally require saturation of these targets. One means of decreasing required drug concentrations is incorporation of reactive metal centers that elicit irreversible modification of targets. A common approach has been the design of artificial proteases/nucleases containing metal centers capable of hydrolyzing targeted proteins or nucleic acids. However, these hydrolytic catalysts typically provide relatively low rate constants for target inactivation. Recently, various catalysts were synthesized that use oxidative mechanisms to selectively cleave/inactivate therapeutic targets, including HIV RRE RNA or angiotensin converting enzyme (ACE). These oxidative mechanisms, which typically involve reactive oxygen species (ROS), provide access to comparatively high rate constants for target inactivation. Target-binding affinity, co-reactant selectivity, reduction potential, coordination unsaturation, ROS products (metal-associated vs metal-dissociated; hydroxyl vs superoxide), and multiple-turnover redox chemistry were studied for each catalyst, and these parameters were related to the efficiency, selectivity, and mechanism(s) of inactivation/cleavage of the corresponding target for each catalyst. Important factors for future oxidative catalyst development are 1) positioning of catalyst reduction potential and redox reactivity to match the physiological environment of use, 2) maintenance of catalyst stability by use of chelates with either high denticity or other means of stabilization, such as the square planar geometric stabilization of Ni- and Cu-ATCUN complexes, 3) optimal rate of inactivation of targets relative to the rate of generation of diffusible ROS, 4) targeting and linker domains that afford better control of catalyst orientation, and 5) general bio-availability and drug delivery requirements.

Purification and characterization of a ribonuclease from the wild edible mushroom Armillaria luteo-virens.

A 15 kDa ribonuclease (RNase) was purified from dried fruiting bodies of the wild edible mushroom Armillaria luteo-virens. The simple 4-step purification protocol involved ion-exchange chromatography on DEAE-cellulose, affinity chromatography on Affi-gel blue gel, ion-exchange chromatography on SP-Sepharose and a final gel filtration by FPLC on Superdex-75. The RNase was unadsorbed on Affi-gel blue gel, but adsorbed on DEAE-cellulose and SP-Sepharose. The N-terminal amino acid sequence of purified RNase was AGVQYKLTILLV, which showed low sequence homology to those of previously reported RNases. The optimal pH and temperature of the enzyme were very close to 4.0 and 70°C, respectively. The enzyme showed considerably high ribonucleolytic activity and broad specificity towards polyhomoribonucleotides, with a specificity of poly(U)>poly(C)>poly (G)>poly(A). The ribonucleolytic activities towards poly(U), poly(C), poly(G) and poly(A) were 279.5, 184.1, 69.9 and 52.3 U/mg, respectively.

Significance and expression of PIWIL1 protein and DICER enzyme in hepatocellular carcinoma / 中华肝胆外科杂志

Objective To explore the expression of PIWIL1 protein and DICER enzyme in hepa tocellular carcinoma (HCC) and their significance.Methods Immunohistochemical method was used to detect the expression of PIWIL1 and DICER in 47 cases of HCC and the adjacent HCC tissues.Western blot method was used to detect the expression of PIWIL1 and DICER in 31 cases of fresh HCC tissues and their adjacent HCC tissues.The relationship between PIWIL1 and DICER and their relationships were analysed with clinical features.12 cases of normal liver tissues were used as control group.Results The expression of PIWIL1 was high in HCC but low in normal liver tissues (P＜ 0.05).The expression of DICER was high in normal liver tissues but low in HCC (P＜0.05).The expression of PIWIL1 was positively correlated with invasion to adjacent tissues and histological differentiation (P＜0.05).The expression of DICER was negatively correlated with invasion to the adjacent tissues and histological differentiation (P＜0.05).There was a negative correlation between PIWIL1 and DICER (P＜ 0.05).Conclusions High expression of PIWIL1 and low/missing expression of DICER was related to pathological differentiation and invasion of adjacent tissues.

Acne Inversa: Evaluating Antimicrobial Peptides and Proteins

BACKGROUND: Acne inversa is a chronic, suppurative relapsing inflammatory skin disease that primarily affects the axillae, perineum and inframammary regions. Evidence suggests that the innate immune system is involved in the pathogenesis of acne inversa. OBJECTIVE: To investigate the role of the innate immune system in acne inversa. METHODS: Skin biopsies were obtained from inflammatory skin lesions (n=17) and from non-lesional skin (intraindividual control, n=17) of patients with acne inversa. Additional skin lesions were taken from patients with chronic venous leg ulcers (interindividual control, n=5). Quantitative real-time reverse transcription-polymerase chain reaction was used to determine the mRNA levels of antimicrobial peptides and proteins (AMPs), including human beta-defensin (hBD)-1, hBD-2 and hBD-3, LL-37 (cathelicidin) and Ribonuclease 7 (RNase 7). mRNA levels were also determined for inflammatory and anti-inflammatory cytokines, including tumor necrosis factor-alpha (TNF-alpha), matrix metalloproteinase-1 (MMP1), interleukin (IL)-1beta, IL-6, IL-8 and IL-10. RESULTS: The mRNA levels of hBD-2, LL-37, IL-1beta, IL-6, IL-8, IL-10 and MMP1 were significantly higher in acne inversa lesions compared to non-lesional skin (p<0.05). A significant positive correlation expression was observed between hBD-2 mRNA expression and LL-37 (rho=0.53, p=0.03), and between hBD-2 and RNAse 7 (rho=0.68, p=0.006). When compared to the chronic venous leg ulcer lesions, acne inversa lesions showed a significantly higher expression of RNase 7 mRNA, while IL-1 beta, IL-6, IL-8, TNF-alpha and MMP1 mRNA expression was significantly higher in the chronic venous leg ulcer lesions (p<0.05). CONCLUSION: The AMP, cytokine milieu and tissue proteases in acne inversa lesions differ significantly from non-lesional skin and chronic venous leg ulcers. The positively correlating up-regulation of AMPs in acne inversa indicates an important role of the innate immune system in the pathogenesis of this disorder.

Targeting therapy of single chain immunotoxin hdsFv-RC-RNase against hepatocellular carcinoma / 中国肿瘤生物治疗杂志

Objective: To observe the targeting therapy of the hdsFv-RC-RNase recombinant single chain immunotoxin on the xenograft of the human hepatocellular carcinoma in nude mice and to explore its clinical potentiality. Methods: The prokaryotic expression vector TIG-hdsFv-RC-RNase was transformed into E.coli BL21(DE3)plys to largely express recombinant single chain immunotoxin hdsFv-RC-RNase against hepatocellular carcinoma induced by IPTG. The expressed product was purified via Ni-NTA affinity chromatography under native conditions and mildly refolded. The ELISA was used to analyze its immunological activity of antigen-binding capability. The xenogrft model of the human hepatocellular carcinoma in nude mice was established and the targeting therapy of hdsFv-RC-RNase was evaluated. Results:After induced by IPTG, a new protein band with M_r 41 000 was found in the supernatant of the bacteria and expressed in a soluble form. The expressed product was purified to homogeneity via Ni-NTA affinity chromatography under native conditions. The results of ELISA showed the refolded hdsFv-RC-RNase had the specific antigen-binding capability to the human hepatocellular carcinoma cell, but not to the normal hepatocyte (P

Polymorphism of black snake venom Ribonuclease II –chromatographical forms

By ion-exchange chromatography, the existance of Ribonuclease from Vietnam’s black cobra. Venum in multiple molecular forms was confirmed. Its two separated peaks were noted on CM-cellulose column chromatography. At present , the nature of these RNase chromatographic forms are unknown, but it is probably that they possess quaternary structure

Polymorphism of Black Snake Venom RNase.I - Two distinct kinetical forms

In the study, using the kinetic method for the examination of the dependence between the specific activity of the enzyme and the concentration of the enzyme itself in the combined reaction, the researchers have proved that the Ribonuclease (R.Nase) molecule of the black cobra (Naja naja) venom exits at least in two interconvertible forms with the difference in specific activity of almost one grade. These two forms are probably the different oligomers or configurations, temporarily named as the kinetic forms of R.Nase found in the black cobra venom.

The construction of eukaryotic expressive vector of RI gene and the effects of the transfected pLNCX-ri on the growth of C6 glioma cells / 中国癌症杂志

Purpose:To clone and construct an eukaryotic expressive vector of ribonuclease inhibitor (RI) gene ,as well as to observe the effects of the transfected pLNCX-ri on the growth of C6 glioma cells.Methods:A segment of RI gene of 1.4 kb was obtained by Nde I/Xho digestion and cloned into pLNCX. Transfective agent and selective antibiotic were lipofect AMINE and G418 respectively. The expression of pLNCX-ri in C6 glioma cells was detected by Western blotting. And SD rats were inoculated by the transfected C6 glioma cells.Results:An eukaryotic expressive vector of RI gene was constructed successfully. RI content was remarkably higher in the transfected cells than that of in the untransfected cells. After SD rats were inoculated by the transfected C6 glioma cells,the tumorigenic time was prolonged, the tumor weight was reduced and the density of tumor vessels was notably decreased. Conclusions:These results indicated that RI gene powerfully inhibited the growth of C6 glioma cells via decreasing tumor vessels formation.