Cofactor engineering, a vital part of metabolism engineering, changes the redox cofactor regeneration approach. Its main goal is to rebuild the components of metabolic products. The bioconversion of xylose for the production of ethanol is being studied intensively because ethanol is an alternative energy source and a potential liquid fuel. Saccharomyces cerevisiae has been traditionally used in producing ethanol from fermentable sugars but it cannot utilize xylose, only its isomer xylulose. Introduction of the xylose fermentation pathway from Pichia stipitis into S. cerevisiae enables xylose utilization in recombinant S. cerevisiae, but the ethanol yields of xylose fermentation with recombinant S. cerevisiae has been low and large amounts of the byproduct xylitol are produced. The major reason is that the catabolism of xylose with the fungal pathway leads an imbalance of redox cofactor. The process of the catabolism of xylose requires NADPH and NAD~+, both of which have to be regenerated in separated processes. More and more attention has therefore focused on the redox cofactor balance in S. cerevisia. The research progress of cofactor engineering to solve the imbalance of redox cofactor in xylose metabolism recombinant S. cerevisiae was introduced. This included expression of transhydrogenase, increasing the utilization of NADPH, and achieving the anaerobic reoxidation of NADH. Reversing the cofactor specificity of enzymes is another effective way.

Objective To observe the influence of highflux hemodialysis(HFD)on homocysteine(Hcy) level and major cardiovascular events of maintenance hemodialysis (MHD) patients. Methods Patients eligible for inclusion were randomly divided into HFD group and low flux hemodialysis(HD)group with 30 cases in each group. Patient′s serum homocysteine (Hcy),major cardiovascular events and various clinical indicators were observed for 12 months then the data were analyzed. Results Hcy baseline levels in 2 groups(21.02 ± 11.79 mmol/L vs. 19.86 ± 6.97 mmol/L)indicated no significant difference(P = 0.162)before hemodialysis but Hcy levels had significant difference(20.29 ± 11.45 mmol/L vs. 24.57 ± 13.23 mmol/L),(P=0.045)after 12-month observation. There was lower incidence of major cardiovascular events in HFD when compared to that in HD group (10.0% vs. 33.3%) which showed significantly statistical difference (P=0.034),and there was no mortality in HFD group but 1 case of death in HD group. All-cause mortality in 2 groups showed no significant difference (P > 0.05). Conclusion Long-term HFD treatment significantly reduces Hcy levels and the incidence of major cardiovascular events of MHD patients

Delightful achievements have been obtained in forestry genetic breeding since the application of transgenic technology in this field during the past 20 years. Field trials of some genetic modified (GM) trees have been carried out, and some GM trees have been commercialized. Meanwhile, the risks of ecological safety caused by GM trees have raised attention in the public gradually. These issues mainly include the horizontal transfer and vertical flow of foreign genes, and the potential effects on insects, soil ecosystems and virus. The current status of field trials, commercial applications and the potential ecological risks of GM trees were summarized. Then the prospects of GM trees were also presented.

Background The identification of mesenchymal stem cells(MSCs) have provided exciting prospects for cell-based regeneration after myocardic infraction.However cell therapy have inherent limitations such as low survival rate of transplanted cells and insufficient cell number.It is known that cell-matrix adhesion plays a key role in cell proliferation,differentiation and survival,and chemokine CXCL12 may involved in these prcesses.Transfected mesenchymalstem cells with CXCL12 for local secretion of CXCL12 and then explored CXCL12 triggered adhesion of mesenchymal stem cells to extracellular matrix proteins.Mesenchymal stem cells was transfected with CXCL12.?V and ?3 integrins content was evaluated by Western blot analysis.Cell adhesion to extracellular matrix was examined in vitro and cell prolife-ration after transplantation in vivo.Transfection of CXCL12 resulted increased CXCL12 in situ.Increased CXCL12 induced elevated adhesion to fibronectin in vitro and higher survival in vivo.CXCL12 mediated adhesion and proliferation was established by ?V and ?3 integrin subunits.Chemoattractive mechanisms are involved in adhesion processes of mesenchymal stem cells.Increased CXCL12 leads to enhanced expression of ?V and ?3 integrins,which may augment cell survival,proliferation and differrentiation.

AIM: To investigate the influence and mechanism of recombinant interleukin-13 (rIL-13) on fibroblasts. METHODS: 3T3 fibroblasts were divided into two groups: the treated group was treated with rIL-13 (80 ?g/L, 24 h or 48 h) and the control was without rIL-13 treatment. Transmission electron microscope and Hoechst kit were used to observe morphology of 3T3 fibroblasts in both groups. The activity of proliferation in both groups was investigated and compared by MTT means. Western blot was used to analyze the level of collagen type I induced by rIL-13 in fibroblasts. The levels of IL-6 and IL-8 in the culture supernatants were determined by radioimmunoassay. RESULTS: The more ribosomes and mitochondrions, as well as bigger nuclei were found in the treated group. The production of IL-6 and IL-8, and proliferation ratio of fibroblasts treated with rIL-13 for 24 h or 48 h were increased obviously, compared with the control (P

Child ; Child, Preschool ; Female ; Heart Defects, Congenital ; complications ; Humans ; Infant ; Infant, Newborn ; Male ; Tracheal Stenosis ; diagnosis ; therapy

Adult ; Bone Neoplasms ; diagnostic imaging ; therapy ; Combined Modality Therapy ; Curettage ; methods ; Embolization, Therapeutic ; methods ; Female ; Follow-Up Studies ; Giant Cell Tumor of Bone ; diagnostic imaging ; therapy ; Humans ; Male ; Sacrum ; Time ; Tomography, X-Ray Computed ; Treatment Outcome ; Young Adult

Objective To summarize the experiences of microsurgery for treatment of middle cerebral artery aneurysms (MCAA). Methods The clinical data of 35 patients with MCAA treated by microsurgery in General Hospital of PLA from 2004 to 2008 were retrospectively reviewed. Of them there were 20 males and 15 females, aged 18 to 72 years with a mean of 40 years. Of the 35 patients, subarachnoid hemorrhage occurred formerly in 22, intracerebral hemorrhage occurred in 11 and subdural hematoma in one patient. The MCAA located in the middle cerebral artery trunk in 10 patients, at the bifurcation in 20 patients (including one patient with 2 MCAAs), and in the distal segment in 5 patients. MCAA located on the left side in 13 and on right side in 22 patients. There were 7 patients with giant aneurysms, 11 with large aneurysms and 17 with small aneurysms. Microneurosurgery was performed in all cases, and different approaches were taken according to the locations of aneurysms. Superior temporal gyrus approach was conducted in 3 patients with giant intracerebral hematoma. Bypass of superficial temporal artery to middle cerebral artery was performed before occlusion of the afferent artery in one patient with giant aneurysm. Bypass with saphenous vein to middle cerebral artery was performed in another patient with giant aneurysm. Results The giant and large MCAAs consisted of 51.4% of all cases. Excellent outcomes were achieved in 20 patients, no marked change in 12 patients, and post-operative complications were observed in 3 patients. No perioperative death occurred. Conclusions Giant and large aneurysms are more common in middle cerebral artery aneurysms. Proper surgical approaches based on different situations during operation should be considered to achieve satisfactory outcome.

Purpose Estimation of the degree of pulmonary artery stenosis (PS) in children patients before treatment can provide an important basis for the choice of treatment.This study explores the accuracy of non-invasive continuous wave Doppler (CW) and electrocardiogram (ECG) in estimating the degree of PS in children patients.Materials and Methods Sixty consecutive cases of PS children were collected from January 2012 to August 2016 in the General Hospital of Shenyang Military.The right ventricular pressure was estimated by measuring cross-pulmonary artery pressure gradient by CW,or estimated by measuring the amplitude of the V1R wave by ECG,which was then compared with that measured by cardiac catheterization respectively.Results The right ventricular pressure estimated by measuring cross-pulmonary artery pressure gradient by CW was positively correlated with that measured by cardiac catheterization (r=0.88,P＜0.05).The right ventricular pressure estimated by measuring the amplitude of the V1R wave by ECG was also positively correlated with that measured by cardiac catheterization (r=0.83,P＜0.05).Conclusion The right ventricular pressure estimated by CW or ECG has good consistency with that measured by cardiac catheterization.Both CW and ECG can be used as noninvasive methods for estimating the degree of PS in children.

Objective To investigate the mitochondrial energy metabolism in D-galactoseinduced cell ageing model.Methods MRC-5 cells were cultivated for 72 hours in a medium containing 55 mmol/L D-galactose.The analysis of cell proliferation capacity by CCK8 method,β-galactosidase staining and detection of p21 protein expression level were performed for identifying cell senescence.The cell oxidation-reduction state was evaluated by an analysis of cellular ROS levels,SOD activity,MDA content and oxidative damage level of mitochondrial DNA(mtDNA).For purpose of detecting mitochondrial function and its impairment,mitochondrial morphology was observed by electron microscope,mitochondrial quantity was analyzed by flow cytometry,mitochondrial membrane potential(△Ψm) was measured by JC-1 staining,and ATP content was analyzed by HPLC,and mitochondrial oxygen consumption rate was detected by Seahorse cell energy metabolism detection system.Results The decreased MRC-5 cell proliferation,up-expression of p21 protein,increased β-galactosidase activity were observed in D-Gal-treated cells,which indicated the cell premature senescence.When treated with D-Gal,the significantly increased ROS and MDA level,decreased SOD activity and increased oxidized mtDNA proved that the cells kept higher oxidative stress.D-Gal induced-mitochondrial impairment was evidenced by the dimming of mitochondrial cristae and double membrane structure,decrease of transmembrane potential and ATP synthesis,and decrease of its oxygen consumption rate(OCR).Conclusions The 55 mmol/L D-Gal causes an impairment of mitochondrial structure and a decrease of function of energy metabolism,which is associated with cellular senescence induced by D-Gal.