BACKGROUNDTo express in vitro the bovine enterokinase catalytic subunit (EKL) protein, which could be used in the future for the cleavage and purification of fusion proteins.

METHODSBovine enterokinase catalytic subunit cDNA was obtained by RT-PCR from duodenal mucosa of a bovine obtained at wholesale market, and then cloned into a pUCmT cloning vector and sequenced. The desired gene fragment was inserted into a pET39b expression plasmid and the recombinant vector pET39b-EKL was transformed into E. coli BL21 (DE3). Protein expression was induced using IPTG. The recombinant DsbA-EKL was purified with His.Tag affinity chromatography, and it bioactivity was analyzed.

RESULTSCompared with the sequence deposited in GenBank, the sequence of the EKL gene cloned in the present study is correct. It was also confirmed that the nucleotide sequence of expression plasmid pET39b-EKL was correct at the conjunction site between the recombinant DNA 5' terminal multi-cloning site and the recombinant fragment. SDS-PAGE analysis indicated that the target product was about 65 kDa and represented 28% of total cell protein. Purified recombinant protein was obtained by metal chelating chromatography using Ni-IDA resin. After desalting and changing the buffer, the crude kinase was incubated at 21 degrees C overnight and shown to have a high autocatalytic cleavage activity.

CONCLUSIONSThe EKL gene from Chinese bovine has been cloned successfully and expressed. This investigation has layed the foundation for future enterokinase activity research and for further large-scale application of expression products.

Animals ; Catalytic Domain ; genetics ; Cattle ; Cloning, Organism ; DNA, Complementary ; Enteropeptidase ; analysis ; genetics ; Recombinant Proteins

Objective To identify interleukin (IL)-17-producing T cells and Foxp3 positive CD4 positive T ceils from patients with rheumatoid arthritis (RA), and investigate their cytokine levels as well as their correlations. Methods Flow cytometry was used to analyze the subsets of T cells in peripheral blood from 39 RA patients and 40 healthy donors. IL-17, IL-6, IL-23 and transforming growth factor (TGF)-beta levels in sera of these subjects were tested by ELISA. Results IL-17+CD4+ T cells increased significantly and IL-17, IL-6 and IL-23 elevated markedly in peripheral blood of RA patients compared to healthy donors (P< 0.01 ). However,Foxp3+CD4+T cells decreased evidently (P<0.01) and TGF-beta did not increase in RA pati-ents when compared to healthy donors (P>0.05). Conclusion This study suggests that Th17 cells predomin-ance coupled with relatively insufficient CD4+ regulatory T cells in RA is mainly caused by alterations of rela-ted cytokines.

Alveolitis, Extrinsic Allergic ; Humans ; Occupational Diseases

Objective To investigate the therapeutic effect of large dose mucosolvan combined variant flow rate continuous positive airway by nasal mask on neonatal respiratory distress syndrome(NRDS).Methods One hundred and fourteen newborns with NRDS were randomly divided into treatment group(58 cases) and control group(56 cases),on the base of same combined therapy,the cases in control group only underwent oxygen-absorbing by head set with the flow rate 4-6 L/min,and the cases in treatment group were given large dose mucosolvan(Ambroxol Hydrochloride) 30 mg/(kg?d) + 5%GS 20 mL,for two times and variant flow rate continuous positive airway by nasal mask(NCPAP),the parameter setting flow rate 6-8 L/min,FiO_2 0.4-0.6,pressure 5-8 cm H_2O.The clinical symptom and blood gas analysis after 12 and 48 hours were observed and compared the changes of pa(O_2),pa(CO_2),pa(O_2)/FiO_2 in two groups.Results The dyspnea and groan in 44 cases in the treatment group lessoned or vanished,pa(O_2) rised and pa(CO_2) lowered,the oxygenation index obviously increased,the cases with RDS grade Ⅰand gradeⅡ had better therapeutic effect,and the cases with RDS grade Ⅲ(X-ray)and Ⅳ had not manifest effect,the total effective rate was 75.8% in treatment group and 26.7% in control group.There were significant difference in therapeutic effect and oxygenation index between two groups.Conclusions Large dose mucosolvan(combi)-ning variant flow rate continuous positive airway by nasal mask can significantly improve the ventilation and oxygenation function and there are significant therapeutic effect in NRDS,especially in the NRDS grade Ⅰand gradeⅡ,the trachea cannula may be avoided and mechanical ventilation rate may be decreased if the therapeutic method can be used in earlier period.

Animals ; Cholestasis ; complications ; Fibrosis ; etiology ; Gallbladder ; pathology ; Humans ; Kidney ; pathology ; Lipid Metabolism ; Liver Cirrhosis ; etiology ; therapy ; Myocardium ; pathology ; Receptors, Cytoplasmic and Nuclear ; physiology

OBJECTIVETo explore the effects and mechanisms of multi-glycoside of Tripterygium wilfordii (GTW) on improving glomerular inflammatory lesion in rats with diabetic nephropathy (DN).

METHODDN model was induced by unilateral nephrectomy and intraperitoneal injection of STZ (35 mg x kg(-1)) twice. The rats were randomly divided into 3 groups, the sham-operated group (Sham group, n = 5), the vehicle-given group (Vehicle group, n = 5 ) and GTW-treated group (GTW group, n = 5). After the model was successfully established, the rats in GTW group were daily oral administrated with GTW suspension (50 mg x kg(-1) x d(-1)), meanwhile, the rats in Vehicle group were daily oral administrated with distilled water (2 mL) for 8 weeks. From the beginning of the administration, all rats were killed 8 weeks later. Blood and renal tissues were collected,and then UAlb, renal function, glomerular morphology characteristics and glomerular macrophages (ED1 + cells) infiltration, as well as the protein expressions of inflammatory cytokines including tumor necrosis factor(TNF)-α and interleukin(IL)-lβ, and the key molecules in p38MAPK signaling pathway including p38 mitogenactivated protein kinase (MAPK), phosphorylated p38 (p-p38MAPK) and transforming growth factor(TGF)-β1 were investigated respectively.

RESULTGTW not only ameliorated the general state of health and body weight,but also attenuated UAlb, glomerulosclerosis, the infiltration of glomerular ED1 + cells and the protein expressions of TNF-α, IL-1β, p-p38MAPK and TGF-β1 in the kidney in DN model rats.

CONCLUSIONBy means of DN model rats, we demonstrated that GTW has the protective effect on renal inflammatory damage in vivo via inhibiting inflammatory cells infiltration and inflammatory cytokines expression. Furthermore, GTW could improve renal inflammatory lesion through down-regulating the expressions of the key signaling molecules in p38MAPK pathway such as p-p38MAPK and TGF-β1 ,and inhibiting the activation of p38MAPK signaling in the kidney.

Animals ; Diabetic Nephropathies ; drug therapy ; Disease Models, Animal ; Glomerulonephritis ; drug therapy ; Glycosides ; pharmacology ; MAP Kinase Signaling System ; drug effects ; Male ; Rats ; Rats, Sprague-Dawley ; Transforming Growth Factor beta1 ; analysis ; Tripterygium ; chemistry ; p38 Mitogen-Activated Protein Kinases ; physiology

Objective: To analyze the relationship between thrombin activatable fibrinolysis inhibitor ( TAFI ) and coronary heart disease ( CHD ), and to provide evidence for the prevention of CHD. Methods: The patients with CHD in Fushun Central Hospital in Liaoning Province were selected as the case group, the patients without CHD in the same hospital and period were selected as the control group. The demographic information and clinical examination results ( serum TAFI, lipid, glucose, etc. ) were collected to analyze the association between TAFI and CHD by logistic regression models.The multivariate logistic regression analysis was used to explore the relationship between TAFI and CHD. Results: There were 222 cases, including 100 cases of stable angina, 44 cases of unstable angina and 78 cases of acute myocardial infarction, and 222 controls. The median ages of cases and controls were 62 and 57 years old. The results of multivariate logistic regression analysis showed that serum TAFI>22.88 μg/mL ( P75 of controls ) was associated with the risk of CHD ( OR=1.619, 95%CI: 1.011-2.593 ), unstable angina ( OR=2.917, 95%CI: 1.433-5.939 ) and acute myocardial infarction ( OR=2.626, 95%CI: 1.007-6.847 ). Conclusion The high level of TAFI is related to CHD, unstable angina and acute myocardial infarction.

The present study is to investigate whether the extracellular signal-regulated kinase (ERK) and cAMP response element binding protein (CREB) signaling pathway contributes to the initiation of chronic constriction injury (CCI)-induced neuropathic pain in rats. Mechanical allodynia was assessed by measuring the hindpaw withdrawal threshold in response to a calibrated series of von Frey hairs. Thermal hyperalgesia was assessed by measuring the latency of paw withdrawal in response to a radiant heat source. The expressions of phosphor-ERK (pERK) and phosphor-CREB (pCREB) were examined using Western blot analysis and immunohistochemistry. An early robust increase in the expression of pERK on the spinal cords ipsilateral to injury was observed on day 1 after CCI, when the CCI-induced behavioral hypersensitivity had not developed yet. Moreover, the upregulation of pERK expression in ipsilateral spinal cord was associated with the increase in pCREB expression in bilateral spinal cord. Intrathecal administration of mitogen-activated protein kinase kinase (MEK) inhibitor U0126 before CCI can efficiently block and delay the CCI-induced mechanical allodynia and thermal hyperalgesia. These data suggest that activation of ERK and CREB in the spinal cord contributes to the initiation of peripheral nerve injury-induced pain hypersensitivity, and an early intervention strategy should be proposed.
Animals ; Butadienes ; pharmacology ; Cyclic AMP Response Element-Binding Protein ; metabolism ; Enzyme Inhibitors ; pharmacology ; Extracellular Signal-Regulated MAP Kinases ; metabolism ; Hyperalgesia ; etiology ; physiopathology ; prevention & control ; Male ; Nitriles ; pharmacology ; Pain ; etiology ; physiopathology ; prevention & control ; Peripheral Nerve Injuries ; complications ; metabolism ; physiopathology ; Rats ; Rats, Sprague-Dawley ; Sciatic Neuropathy ; metabolism ; physiopathology ; Spinal Cord ; metabolism

OBJECTIVETo explore the relationship between sample size and variance of means for personal noise exposure in weaving workers as to contributing evidence for establishing personal noise exposure measurement guideline.

METHODSA personal noise exposure measurement database from a group of weaving workers was used in the randomized re-sampling data analysis. The sampling cases were one number selecting from one to fifteen at each randomized re-sampling procedure. The randomized re-sampling was one thousand times from original personal noise exposure measurement database to get one thousands of re-sampling database. One thousands of L(Aeq.8 h) mean were calculated by re-sampling databases. The variation of randomized re-sampling means was analyzed for different re-sampling numbers.

RESULTSThe change for narrow trend of maximum, minimum, 95 percent number, 5 percent number of L(Aeq.8 h) mean was faster when randomized re-sampling number was smaller in variation vs randomized re-sampling number curve analysis. After that, the change for narrow trend of L(Aeq.8 h) mean was smooth for increasing the randomized re-sampling numbers. The 95% - 5% of L(Aeq.8 h) mean was about half for randomized re-sampling four cases (3.30 dB) vs one case (7.40 dB), and about one third for seven cases (2.44 dB), and about one fourth for eleven cases (1.85 dB).

CONCLUSIONThe sample size in personal noise exposure measurement guideline could be selected from four to eleven.

Humans ; Noise, Occupational ; statistics & numerical data ; Occupational Exposure ; statistics & numerical data ; Sample Size ; Sampling Studies

OBJECTIVETo investigate the application of 293 cells to detect suspected carcinogens and provide experimental evidence by using in vitro cell transformation assay and tumorigenicity study.

METHODSThe transformation systems of cells cultured in vitro have been adopted to clarify the tumor promotive activity of Microcystin LR (MC-LR). The malignant transformation of 293 cells induced by MC-LR is tested by several methods including clone forming in soft agarose, serum requirement assay and tumor forming in mice to define the promotive activity of 293 cells.

RESULTS293 cell acted like tumor cells after induced by MC-LR: serum dependence decreased, anchorage independence growth in soft agarose and formed cell clones, malignant tumors appeared in SCID mice.

CONCLUSION293 cells were easy to culture and sensitive to environmental carcinogens so that can be used in detection of suspicious carcinogens.

Animals ; Carcinogenicity Tests ; methods ; Carcinogens ; toxicity ; Cell Line ; drug effects ; Cell Transformation, Neoplastic ; drug effects ; Humans ; Mice ; Mice, SCID ; Microcystins ; toxicity