In recent years,more and more of the enzyme proteins have been carried out using recombinant microorganism bioreactor for large scale production.For reasons of improved the catalytic capability and environmental suitability,or enhanced expression level of the protein,a variety of genetic engineering technology according to protein molecule modification have been applied extensively.Major strategies and achievements of molecular modification for microbial enzyme,such as site-directed mutagenesis,error-prone PCR,DNA shuffling and optimum codon design were reviewed.

Recent studies show that epileptic seizures result in mass free radical production and induce oxidative damage because of relative deficiency in anti-oxygen system.Mitochondrium is crucial to sustaining energy metabolism,regulating cell death,synthesising neurotransmitter and oxidating fatty acid.Mitochondrium is not only the place for free radical production,but also the target of oxidative damage.Mitochondrial oxidative stress and resultant dysfunction enhance epileptic susceptibility.Seizure-induced free radical can influence energy metabolism,destroy DNA construction and induce apoptosis in neurontoxic consequences in epilepsy.

Adenosine deaminase (ADA)plays an important role in the regulation of normal immune system.The altered activ-ity of serum ADA could associate with some autoimmune diseases(AID).Various studies abroad have found the elevated ac-tivity of serum ADA compared with healthy controls in many kinds of AID such as systemic lupus erythematosus (SLE), rheumatoid arthritis(RA),et al (P<0.05).Many studies foused on the correlation of altered activity of serum ADA with the disease severity,but there is still controversy.To explore the diagnostic value of serum ADA in AID,make a review a-bout the application research progress of ADA in several AID.

Objective To explore a simple and convenient method for the treatment of penis skin defect.Methods Since Jan.1995,the scrotal skin flaps have been used to repair the defects of the penis skin in 8 patients with penis skin infection.6 of these cases lost their whole penis skin,and 2 of them lost 2/3 of their penis skin.The granulation tissues in the defective area of penis skin were cut away,and then the normal aponeurosis of corpus cavernosum or spongiosum exposed.The scrotal skin flaps were designed and shaped.The flaps were transferred to cover the defects,and the incisions were closed.Results All the flaps in 8 cases survived completely.The follow-up period was 3 to 12 months after operation.All cases obtained satisfactory results to the contour and function of the penises.Conclusion This procedure is a much better method for repairing skin defects in the penis.It can be easily operated and completed in one-stage.The postoperative results are satisfactory.

Objective To investigate the characteristics of depression in the chronic hepatitis C (CHC) patients who received pegylated interferon therapy.Methods Clinical data of 218 CHC patients who were treated with pegylated interferon were collected in Huzhou Central Hospital,Zhengjiang from January 2008 to December 2013.The Hamilton Depression Rating Scale (HAMD) was used to assess the patient's depression symptoms during the treatment process.The sustained virological response (SVR) rate was assessed 24 weeks after the completion of treatment.Chi square test was used to compare the effects of treatment,gender,age,different types of interferon during the treatment process on depression,and to analyze the dynamic changes of depression and the effect of depression on SVR.Results Of the 218 CHC patients who completed pegylated interferon treatment,the proportion of patients with HAMD score ≥8 (n=73,33.19％) after treatment was significantly higher than that before treatment (n=20,9.17％;x2=40.321,P＜0.05).The female CHC patients were more prone to have depressive symptoms than the male patients (40.50％o [49/121] vs 24.74％ [24/97];x2 =6.097,P＜0.05).The incidence rate of depression in patients younger than 55 years old was lower than that of over 55 years (27.48％ [36/131] vs42.53％ [37/87];x2=5.271,P＜0.05).The incidence rate was not significant different between pegylated interferon α-2a group and pegylated interferon α-2b group after treatment (35.04％ [41/117] vs31.68％ [32/01];x2=0.275,P＞0.05).At week 8 of treatment,the number of depression patients increased most significantly.Totally 113 (51.83 ％) of 218 patients achieved SVR,including 57.53％ (42/73) of patients with depression and 48.97％ (71/145) of patients without depression,but there was no statistical significance (x2 =1.432,P＞0.05).Conclusion In CHC patients received pegylated interferon treatment,elderly and female patients are more susceptible to develop depression and the incidence of depression peaks at week 8 of treatment.

Lithium carbonate could be used to treat or prevent brain damage following traumatic injury and neurodegenerative diseases.It has been shown that its protective effect is related to protein kinase C (PKC) and extracellular signal-related kinase (ERK).It was demonstrated that PDBu,a PKC activator,inhibited amplitudes of delayed rectifier potassium current (It,) and produced a hyperpolarizing shift in the activation-voltage curve.The responses to PDBu were inhibited by lithium carbonate (50μmol/L).Further studies showed that when pretreated with MEK/ERK inhibitor U0126 (20 μmol/L),although PDBu significantly reduced IK,lithium did not reverse the effect of PDBu.Thus,the results suggested that PKC signaling cascades,along with MAPK (mitogen-activated protein kinase) pathway,were required in the phosphorylation of potassium channel,which was presented by regulation of potassium channel characteristic.AC-cAMP and their eross-talk with GC-cGMP pathway could also modulate the effect of lithium on PKC activation,which could be one of underlying mechanisms likely related to neuroprotective effect of lithium.

Objective To investigate the predicative value of midkine (MK) as a cancer biomarker for metastatic lesions in differentiated thyroid cancer (DTC) patients with positive thyroglobulin antibodies (TgAb) before the first 131Ⅰ therapy.Methods MK levels were measured by enzyme-linked immunosorbent assay in 151 recruited DTC patients included in this study according to strict inclusion and exclusion criteria.There were 28 TgAb positive DTC patients with metastases and 123 DTC patients without metastases.The value of pre-131Ⅰ-ablative MK to predict metastasis was assessed by receiver operating characteristic (ROC) curves in these two groups of patients.Results MK levels were significantly higher in TgAb positive DTC patients than those in DTC patients without metastases.MK levels showed good diagnostic value,with an area under the curve of 0.856 (P＜0.001),and a diagnostic accuracy of 83％ at the optimal cut-off value of 550 ng/L.Conclusion Results show that MK can potentially be used as a surrogate biomarker for predicting DTC metastases when thyroglobulin is not suitable due to TgAb positivity.

Most main oilfields in China have already entered a "double high" development stage (high water cut, high recovery degree). To further enhance oil recovery in reservoirs after polymer flooding (RAPFs), an efficient activator formulation for promoting metabolism of endogenous microorganism was studied by aerogenic experiments, physical simulation experiments, electron microscopy scanning and pyrophosphate sequencing. Results show that the activator could activate the endogenous microorganisms in the injected water and make the pressurized gas reach 2 MPa after 60 d static culture of the activator in a high pressure vessel. The oil recovery efficiency of natural core physical simulation flooding can be improved by more than 3.0% (OOIP) in RAPFs when injected 0.35 PV activator with 1.8% mass concentration, and a lot of growth and reproduction of activated endogenous microorganism in the core was observed by electron microscopy scanning. Field trial with 1 injector and 4 producers was carried out in the east of south II block of Sa Nan in December 2011. By monitoring four effective production wells, changes of carbon isotope δ13C (PDB) content of methane and carbon dioxide were -45 per thousand to -54 per thousand and 7 per thousand to 12 per thousand. Compared with east II of Sa Nan block, the oil amount increased by 35.9%, water cut stabled at 94%. The incremental oil was 5 957 t during the three and a half years, which provides an alternative approach for further improving oil recovery in similar reservoirs.
Carbon Dioxide ; chemistry ; Carbon Isotopes ; analysis ; China ; Diphosphates ; chemistry ; Methane ; chemistry ; Oil and Gas Fields ; microbiology ; Polymers ; Water ; Water Microbiology

Objective To report the primary experience of open placement of triple-branched stent graft for acute Stanford type A aortic dissection. Methods Between June 2008 and September 2009, 20 well-selected patients with acute Stanford type A aortic dissection underwent open placement of triple-branched stent graft for total arch reconstruction. When core cooling to a 20℃ nasophageal temperature, perfusion to the lower body was discontinued and the ascending aorta was transected at the base of the innominate artery. Through a transverse incision, the triple-branched stent graft was inserted into the true lumen of the arch and descending aorta, and each side arm of the stent graft was positioned one by one into the arch branches.The transected stump of the ascending aorta was reconstructed by inner proximal stent-free dacron tube of the main graft and outer teflon felt, and subsequently continuous anastomosis to the 1-branched dacron tube graft was made. Results Open placement of triple-branched stent graft was technically successful in all patients. The mean cardiopulmonary bypass time, aortic cross-clamp time and lower body arrest time were (163.2 ±19.2) min, (89.4 ±10.0) min and (32. 7 ±6. 6)min, respectively. Transient postoperative neurological dysfunction was observed in 1 patient and acute renal failure in 1 patient. All patients were discharged from the hospital. Their computed tomographic scans at 3 months postoperatively showed that all stent grafts were fully opened without distortion. In the vascular stent implantation site the dissected false lumen was eliminated. The false lumen of the descending aorta distal to the stent graft was closed with thrombus in 16 cases. Conclusion Open placement of triple-branched stent graft is a new effective technique for total arch reconstruction in acute type A aortic dissection. Patients have the indications of the extensive primary repair of the thoracic aorta without primary intimal tears in the arch may be the best candidates for this new technique. The size of the stent graft, the distances between two neighboring side arm grafts and the prevention of the intimal trauma during the placement are crucial for successful open placement of triple-branched stent graft.

Hyperuricemia and metabolic syndrome were studied in 17 762 subjects of Tianjin Municipality from July 2007 to July 2009. The overall prevalence rate of hyperuricemia was 12. 16% (2160cases) , the rate in males was significantly higher than that in females (15. 71% vs. 6. 51% , P <0. 01).The overall prevalence rate of metabolic syndrome was 25. 56% (4540 cases) , the rate in males was also higher than that in females (28. 17% vs. 21. 40% , P <0. 01). Binary logistic regression analysis disclosed that females with high uric acid were twice likely to suffer from metabolic syndrome than males; and female ≤ 44 years with hyperuricemia had the highest odd ratio for metabolic syndrome.