Advances in enzyme immobilization based on hierarchical porous metal-organic frameworks / 生物工程学报

As an excellent hosting matrices for enzyme immobilization, metal-organic framework (MOFs) provides superior physical and chemical protection for biocatalytic reactions. In recent years, the hierarchical porous metal-organic frameworks (HP-MOFs) have shown great potential in enzyme immobilization due to their flexible structural advantages. To date, a variety of HP-MOFs with intrinsic or defective porous have been developed for the immobilization of enzymes. The catalytic activity, stability and reusability of enzyme@HP-MOFs composites are significantly enhanced. This review systematically summarized the strategies for developing enzyme@HP-MOFs composites. In addition, the latest applications of enzyme@HP-MOFs composites in catalytic synthesis, biosensing and biomedicine were described. Moreover, the challenges and opportunities in this field were discussed and envisioned.

Effect of angiotensin-converting enzyme inhibitor on acute kidney injury in patients with sepsis / 中华急诊医学杂志

Objective To investigate the protective effect of angiotensin-converting enzyme inhibitor (ACEI) on kidney function in patients with sepsis.Methods Eighty-seven patients with sepsis were randomly (random number) divided into the routine treatment (A group,n ＝45) and the ACEI intervention group (B group,n =42).Patients were managed by international guidelines for sepsis in A group and were treated with benazepril (ACEI) 20 mg a day in addition in B group.Serum creatinine and cystatin C were detected and APACHE Ⅱ scores and urine output were recorded on the 1st,3rd and 7th day.Those laboratory findings and APACH Ⅱ score were compared between two groups.The incidence of acute kidney injury (AKI) and abnormal cystatin C levels were compared between two groups.Results In B group,serum creatinine and cystatin C of patients were lower compared with A group.The incidence of AKI and abnormal cystatin C and APACHE Ⅱ scores were reduced in B group compared with the A group.Conclusions Benazepril improved sepsis-induced AKI and patient conditions.

Separation and purification of recombinant thymosin alpha 1 and interferon alfacon-1 fusion protein / 中国组织工程研究

BACKGROUND: It demonstrated that combined application of thymosin α 1 (TM-α1) and interferon (IFN) can enhance the antiviral activity of IFN.OBJECTIVE: To obtain recombinant fusion protein of TM- α1 and consensus IFN α (IFN α -con) with double activity of antiviral activity and immunity enhancement.DESIGN, TIME AND SETTING: The in vitro contrast experiment was conducted in the Biochemical Laboratory of Research Institute of Medicine, Chongqing K.E.W Pharmaceutical Co., Ltd. from March 2003 to December 2004.MATERIALS: The fusion gene fragment (TM- α 1+IFN α -con) was synthesized by Shanghai Sangon Biological Engineering Technology And Service Co., Ltd, WISH cell, and vesicular stomatitis virus (VSV) was purchased from Institute of Biochemistry and Cell Biology, commercial products of IFN α 1b, IFN α 2a and TM- α 1 was served as reference substance.METHODS: The preference for E. coli of fusion sequence coding TM- α 1 and IFN α -con were cloned into expression vector of pET-22b(+) and expressed in BL21(DE3)-Codon plus-RP-X, which was purified by precipitation of (NH4)2SO4, hydrophobic interaction chromatography, anion-exchange chromatography, cation-exchange chromatography and molecular exclusion chromatography. The antiviral activity of fusion protein was tested by cytopathic-effect inhibition assay, and effect of fusion protein on lymphocyte proliferation was tested by cell proliferative assay.MAIN OUTCOME MEASURES: The specific activity of fusion protein and its biological activity in promoting lymphocyte proliferation.RESULTS: The fusion protein was expressed as a soluble form, accounting for over 20% of the total cell protein in E. coli, which approached 96% after purification. The antiviral activity of fusion protein was superior to IFN α 1b and IFN α 2a. However, the activity of fusion protein for promoting lymphocyte proliferation was similar to TM- α 1.CONCLUSION: The fusion protein of TM- α 1 and IFN α -con expressed in E. coli has both effects on anti-virus and promoting lymphocyte proliferation.

Expression and activity analysis of interferonalpha-con and thymosin-alpha1 / 生物工程学报

This study aimed to obtain recombinant fusion protein of thymosin alphal(TM-alpha1) and consensus IFNalpha (IFNalpha-con) which have bath TM-alpha1 and IFNalpha-con activities. The DNA sequence for the fusion protein was cloned into expression vector of pET-22b (+) and expressed in BL21 (DE3)-Codon plus-RP-X. The expressed product (TM-alpha1-IFN-con) was soluble, and amounted to more than 20% in total proteins of E. coli. By precipitation of (NH4)2SO4, hydrophobic interaction chromatography (HIC, Phenyl Sepharose 6 Fast Flow), anion-exchange chromatography (Q Sepharose Fast Flow), cation-exchange chromatography (SP Sepharose Fast Flow) and gel filtration (Sephadex G-75), it was purified to more than 96% purity. The activity of fusion protein for antivirus was tested by cytopathic-effect inhibition assay and activity for promoting lymphocyte proliferation was tested by cell proliferative assay. The activity for antivirus was higher than commercial IFNalpha1b and IFNalpha2a and activity for promoting lymphocyte proliferation was similar to commercial TM-alpha1. The fusion protein had better effect for anti-HBV in vitro, its effect was stronger than combination of IFNalpha and TM-alpha1 and cell toxicity was less than combination of IFNalpha and TM-alpha1. The above results show that it has effect bath antivirus of IFNalpha and promoting lymphocyte proliferation of the soluble fusion protein expressed in E. coli.

Effects and relations of carvedilol on heart rate turbulence and secretion of sympathetic nerve in patients with myocardial infarction / 中国基层医药

Objective To investigate the effects and relations of carvedilol on heart rate turbulence and secretion of sympathetic nerve in patients with myocardial infarction. Methods Sixty-six patients selected with acute myocardial infarction were randomized to enroll into experimental group ( n = 33 ) treated with earvedilol and control group( n = 33 ) treated with metoprolol for 12 months follow-up treatment. The concenrrarions of plasma norepinephrine(NE) and epinephrine (E) and 24 hour Holter monitoring were messured respectively before the treatment ,after 6 months and 12 months; and new cardiac events were supervised for all cases. Quantification of heart rate turbulenee(HRT) were carried out by computer analyzing two factors: turbulence onset(TO) and turbulence slope(TS) from the data of 24 hour Holter monitoring. NE,E,TO,TS and the occurrence rate of new cardiac events were compared between two groups and in different times of treatment. The correlation between TO,TS and NE,E was analysed. Results Before the treatment, there was no significant differences between two groups to the comparisons of NE,E,TO and TS(P＞0.05). After treating 6 and 12 months, NE, E and TO of experimental group were all lower than control group's significantly, accordingly TS were all higher(P＜0.05). By comparing 3 times( before,after 6 and 12 months of treatment), NE, E and TO of two groups dropped, meanwhile TS rose; experimental group showed significant changes( P＜0.05 ), but control group showed no significant differences(P＞0.05 ). The occurrence rate of new cardiac events of experimental group was lower than control group's significantly (P＜0.05 ).There was significant correlation between NE, E and TO, TS (P＜0.05 ). Conclusion Carvedilol treatment can block the secretion of sympathetic nerve after myocardial infarction and prevent the occurrences of new cardiac events significantly; the changes of the secretion of sympathetic nerve can play an important role for heart rate turbulence (HRT) ,the changes of HRT would be hopeful to predict new cardiac events alter myocardial infarction.

Effect of carvedilol on the stability of plasma catecholamine in patients with myocardial infarction / 中国基层医药

Objective To study the effects of carvedilol on the stability of plasma catecholamine in patients with post-acute myocardial infarction during consecutive periods. Methods Thirty-slx patients selected with acute myocardial infarction were randomized to experimental group treated with the nonselective beta-blocker earvedilol( n=18) and control group treated with the selective beta-blocker metoprolol(=18) for 12-months follow-up. In the two groups,the concentrations of plasma norepinephrine and epinephrine were measured before the treatment and after 2 months,4 months,6 months,8 mouths,10 months and 12 months and new cardiac events were supervised. Results After the treatment, in each point of periods, experimental group showed lower concentrations of plasma norepinephrine and epinephrine statistically than control group(P<0.05) ,and a stable dynamic change during 12 months of treat-ment( P>0.05 ) ;the occurrence rate of new cardiac events was lower significantly in experimental group than in con-trol group(P<0.05). Conclusion Carvedilol can decrease the spillover of sympathetic nerve, control more stably cardiac sympathetic nerve activity and then decrease more sharply the occurrence rate of new cardiac events in pa-tients with acute myocardial infarction than metoprolol.

Effect of recombinant human troponin C on the growth of human umbilical vein endothelial cells and mouse xenograft tumor / 中国组织工程研究

BACKGROUND: Troponin I (Tn I ) could inhibit the growth of vascular endothelial cells, inhibit neovascularization,through which to inhibit the development and metastasis of solid tumor. Similar to Tn I, TnC also exists in non-muscular tissue, but does it has the analogous activity of anticancer like Tn I ?OBJECTIVE: To explore the effect of recombinant human TnC (rhTnC) on the growth of human umbilical vein endothelial cells (HUV-EC) and mouse xenograft tumor.DESIGN: Controlled observation in vivo and in vitro.SETTING: Research Institute of Medicine, Chongqing K.E.W Pharmaceutical Co., Ltd. and Department of Biochemistry of Chongqing Medical University.MATERIALS: The experiment was conducted in the Biochemical Laboratory of Research Institute of Medicine,Chongqing K.E.W Pharmaceutical Co., Ltd. from March 2003 to December 2004. 100 Kunming mice either male or female of 15-22 g purchased from Chongqing Academy of Chinese Materia Medica. E.coli BL21 (DE3)pLysS/pET3b-TnC provided by Chongqing K.E.W Pharmaceutical Co., Ltd. HUV-EC (Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences).METHODS: Human TnC cDNA was obtained from human thymus cDNA library using PCR. The colony was cloned in E.coli and a bacterial strain of gene engineering E.coli BL21 (DE3) pLysS/pET3b-TnC was obtained, which could express hTnC. The recombinant human TnC (rhTnC) was purified with affinity chromatography of Ni-NTA agarose. ①In vitro cell experiment: HUV-ECs were seeded in the 96-well plates at density of 2×103 cells per well and co-cultured with rhTnC of 1, 5, 10, and 50 mg/L for 3 days. The absorption (A value) was detected with microplate reader at 540 nm and the inhibition rate of cell growth was calculated. Meanwhile, the 50% inhibiting dose (IC50 value) was assayed by LOGIT method. ②In vivo animal experiment: Ascites tumor (S-180) that had been inoculated for 7-8 days was harvested. The tumor cells were diluted to 1 ×1010 L-1 and 0.2 rnL was subaxillarily and intraperitoneally injected into each mouse (50 mice in each group). The next day, the mice were randomly divided into 5 groups: rhTnC 20 mg/kg group, rhTnC 10 mg/kg group, rhTnC 5 mg/kg group, Cyclophosphamide (Cy) group and control group with 10 mice in each group. The rhTnC 20,10 and 5 mg/kg groups were given administration at the corresponding doses, once a day for 7 days; 50 mg/kg Cy was given the Cy group one after an interval of day, and the same volume normal saline was given to the control group. One day after the last time of administration, all mice were killed and the tumor was harvested and weighed. The inhibition rate of tumor growth was calculated: tumor inhibition rate=[(Average weight of tumor in control group-Average weight of tumor in drug group)/Average weight of control group]×100%.MAIN OUTCOME MEASURES: Inhibition rate of rhTnC to HUV-EC proliferation in cell experiment in vitro and mouse xenograft tumor in animal experiment in vivo.RESULTS: ①In vitro cell culture showed that rhTnC suppressed HUV-EC proliferation in a dose-dependent manner (IC50=7.5 mg/L). ②Similar to the result of in vitro cell experiment, after intraperitoneal administration, the inhibition rate of rhTnC 5, 10, and 20 mg/kg groups was higher than that of control group (P ＜ 0.01); after subaxillary administration, the inhibition rate of rhTnC 5, 10, and 20 mg/kg groups was also higher than that of control group (P ＜ 0.05-0.01). There was no significant difference in the inhibition rate between two administration approaches (P ＞ 0.05).CONCLUSION: rhTnC is capable of inhibiting the proliferation of HUV-EC dose-dependently, and displays the activities of inhibiting the proliferation of HUV-EC and anti-tumor.

The change of nuclear factor ?B activity in peripheral blood monocytes in patients with acute coronary syndrome / 中华急诊医学杂志

Objective To investigate the role of nuclear factor ?B activation in the onset of acute coronary syndrome(ACS).Methods 76 patients with acute myocardial infraction(AMI),41 patients with unstable angina pectoris(UAP),43 patients with stable angina pectoris(SAP)and 20 normal controls were enrolled.NF-?B activation in monocytes in peripheral blood monocyte was determined by ELISA with the NF-?B p65 Kit the at 3 and 5 days after admission.Results The activity of NF-?B in monocytes of peripheral blood in AMI patients and UAP patients was significantly higher than that in SAP patients and normal controls(P

Influence of the excision of cardiac sympathetic nerves on QT dispersion / 中国病理生理杂志

AIM: To observe and study the influence of cardiac sympathetic nerve on QT dispersion (QTd) and the circadian variations of QTd in experimental rabbits. METHODS: The rabbits were divided into experimental group (without cardiac sympathetic control by operation) and control group (with retained cardiac sympathetic control by operation, sham operation). QTd of both groups were measured and compared before and after the operation. The circadian variations of QTd were also observed in both groups. RESULTS: QTd in experimental group decreased significantly after the cardiac sympathetic nerves were excised (P

Relationship between QT dispersion and autonomic nerve of heart / 中国病理生理杂志

QT dispersion(QTd,equals maximal minus minimal QT interval on a standard ECG) has been shown to reflect inhomogeneity of myocardial repolarization and cardial electrical instability, hence,been proposed to be associated with ventricular arrhythmias.But the intrinsical mechanism of QTd is incompletely understood. Contributing to QTd are differences of action potential duration(APD) in the three-dimensional structure of ventricular myocardium, which is identified to own three cell subtypes:endocardial, midmyocardial(M cells) and epicardial cells.And findings suggest that regional differences in the duration of the M cell action potential may lead transmural and spatial dispersion of repolarization. Autonomic nerves by combining receptors on the myocardial cells,especially M cells affect significantly the APD.Concordance between heterogeneity of ventricular myocardium and heterogeneity of autonomic innervation in heart provide support for the role of autonomic nerve in the generation of the QT dispersion.