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.

BACKGROUND:Functional changes of some functional genes have been showed to trigger osteoarthritis, among which, age may be a critical one. OBJECTIVE:To summarize the clinical manifestations of osteoarthritis and the research process of silent information regulation 1 in the occurrence and development of osteoarthritis. METHODS:A computer-based retrieval was performed in the databases of CNKI, PubMed, SpringerLink, and Elsevier Science Direct using the keywords ofosteoarthritis, silent information regulation 1 and cartilagein Chinese and English, respectively. Finally 83 eligible literatures were enrolled for analysis. RESULTS AND CONCLUSION:Deacetylation modification acts on the occurrence and development of osteoarthritis by regulating the expression and biological function of various cytokines. Silent information regulation 1 cannot only regulate body metabolism, inhibit cellapoptosis, repair DNA injury, delay senescence and resist to stress, but also play important roles in the epigenetic modification, gene silencing and signal transduction. Therefore, silent information regulation 1 is involved in the age-related diseases, such as osteoarthritis, osteoporosis, diabetes and Alzheimer's disease. Furthermore, silent information regulation 1 is likely to be an important target of osteoarthritis drugs, and even reverses mechanical stress-induced cartilage injury in the early stage of osteoarthritis.

Objective To determine whether vascular endothelial growth factor (VEGF) could be used as a tumor marker by detecting the VEGF levels in serum and effusion from malignant tumor patients. Methods VEGF concentrations were measured using an enzyme-linked immunosorbent assay in the serum from the healthy donors and in the serum and the malignant effusion from the patients. Results The serum VEGF levels from the malignant tumor patients was higher than that from the healthy donors, and there was a significant difference ( P

Background At present,researches about retinitis and acquired immunodeficiency syndrome (AIDS) mainly focus on observation and analysis of the cytomegalovirus (CMV)-induced ocular complication.To screen the effective drugs is very important for the treatment of AIDS-related CMV-induced retinitis.Objective This study was to describe the clinical features,diagnosis and treatment outcome of CMV-induced retinitis with BAY 38-4766 and evaluate the relationship between CMV retinitis and AIDS.Methods This was a case observational study.A total of 154 eyes of 84 patients with CMV retinitis and AIDS were enrolled in this study.Before the definitive diagnosis of CMV retinitis,the AIDS course of these patients were 4-26 months.In the initial examination,the visual acuity ranged from finger counting to 0.4,and the number of CD4+ T-lymphocyte was 0-30 cells/μl.The survival time in the patients ranged from 3 weeks to 18 months.BAY 38-4766 was used in 117 eyes of 62 patients,and 102 eyes of 53 patients showed the srinked of retinal lesion and improvement of vision (0.1-0.7).BAY 38-4766 was used to treat the CMV retinitis in 117 eyes of 62 patients with the initial intravenous dose of 5 mg/kg,twice per day for consecutive 2 weeks and followed by oral dose 1 gram per day.The follow-up duration was 2 weeks to 18 months.The fundus feature,visual acuity and CD4+ T-lymphocyte counts were analyzed.This study proposal was approved by Ethic Committee of the 474th Hospital of PLA,and written informed consent was obtained from each patient prior to entering this study.Results The numbers of CD4+T-lymphocytes increased to 12-402 eells/μl after administration of BAY 38-4766.The CMV retinitis aggravated and the vision decreased in the untreated 22 patients with the CD4+T-lymphocytes 0-30 cells/μl.Conclusions CMV retinitis is the most common intraocular complication in patients with AIDS.Diagnosis of CMV retinitis is based on the characteristics of necrotizing retinitis,which is typically associated with retinal hemorrhage and vasculitis.BAY 38-4766 is an effective drug for the treatment of CMV retinitis.

Objective To explore the relationship between cough variant asthma (CVA) and mycoplasma pneumoniae (MP) infection.Methods Fifty children with CVA were chosen as the experimental group at random,and 50 children with acute upper respiratory infection,who went to the hospital in the same time and with similar age,were chosen as control group.The MP-IgM of children in both groups were tested by the granule agglutinating method.Results Significant difference (? 2=9.013 P

Objective To observe the expression of osteoprotegerin (OPG), receptor activator of nuclear factor κβ ligand(RANKL) and receptor activator of nuclear factor κβ (RANK) in bone tissue of rats with chronic fluorosis and to explore the relation between OPG/RANKL/RANK system and bone damage in chronic fluoride poisoning rat and the antagonism effects of Danlan Xianpeng capsule. Methods SD rats were randomly divided into six groups according to body weight (equal male and female in each group): fluorosis group, high dose drug group, medium dose drug group, low dose drug group, control group, borax group(positive control), 12 rats in each group. The control group drank tap water and the remaining 5 experimental groups consumed 50 mg/L fluoride water, and high, medium and low doses drug group took Danlan Xianpeng capsule at doses of 0.8,0.4,0.2 g/kg,borax group took borax at dose of 0.8 g/kg. OPG, RANKL, RANK protein in rat tibial metaphysis was detected by immunohistochemistry at the 6 month. Results Compared with the control group(173.79 ± 5.23, 174.17 ± 5.01,155.63 ± 7.11), the expressions of OPG, RANKL were increased and the expression of RANK was decreased in fluorosis group(156.83 ± 5.80, 157.74 ± 6.70, 173.92 ± 4.37), the difference was statistically significant (all P ＜ 0.05). Compared with the fluorosis group, the expression of OPG and RANKL were decreased and the expression of RANK was increased in high-dose drug group, middle-dose drug group(169.67±5.07, 168.08 ± 5.05,162.12 ± 4.24, 170.78 ± 5.01, 168.41 ± 7.19, 166.69 ± 5.78, all P ＜ 0.05). Compared with the borax group (167.27 ± 4.08, 167.85 ± 5.01, 166.14 ± 3.95), the expression of OPG and RANKL was increased in the low-dose drug group (163.40 ± 4.11, 159.49 ± 5.78), the expression of RANK was increased in the high-dose drug group (162.12 ± 4.24) and decreased in the low-dose drug group(171.54 ± 8.06), the difference was statistically significant (all P ＜ 0.05). Conclusions Chronic fluoride poisoning can cause increased bone turnover and enhance the activity of osteoelastic absorption by increasing RANKL. Danlan Xianpeng capsule can affect bone remodeling through the OPG/RANKL/RANK system, and antagonises bone damage caused by fluoride.

Child, Preschool ; Humans ; Male ; Neonatology ; Research Report ; Sarcoma, Myeloid ; physiopathology

The microstructure of cationic cyclopeptide (TD-34) treated Caco-2 cell membrane was observed, and we discussed the relationship between membrane structure and insulin transmembrane permeability. Atomic force microscope (AFM) was used to observe living cell membrane in air condition and tapping mode. Results showed that the surface of Caco-2 cell membrane treated with TD-34 lost its smoothness and nearly doubled its roughness. Apparent permeability coefficients (P(app)) of insulin in Caco-2 cell monolayers increased 2.5 times. In conclusion, AFM can be used to observe microstructure of cationic cyclopeptide treated cell membrane and cationic cyclopeptide enhanced insulin delivery across Caco-2 cell membrane by increasing membrane fluidity.
Caco-2 Cells ; Cations ; Cell Membrane ; drug effects ; Cell Membrane Permeability ; drug effects ; Humans ; Insulin ; metabolism ; Membrane Fluidity ; drug effects ; Microscopy, Atomic Force ; Peptides, Cyclic ; pharmacology

Objective To investigate the regulation expression of leukemia inhibitory factor(LIF)in hu- man and animal osteoarthritic(OA)tissues and its clinical relevance.Methods 1)Thirty-five Japanese rabbits, aged eight months,were used to make models of experimental osteoarthritis.Operations were performed at the right knee and the sham ones at the left knee in each rabbit.Rabbits were sacrificed on the 3,7,14,28,42,56 and 84 days after operation respectively.Cartilage and synovium of the knee were collected to observe histological changes of osteoarthritis at different times;immunohistochemistry analysis was conducted to observe the LIF expression and distribution in the cartilage and synovium of the animals.2)From April 2003 to October 2003,32 samples of human articular tissues(cartilage,subchondral bone and synovium)were obtained in the operational procedures and a good quantity of RNA was isolated using Magnetic Beads.The patients who underwent articular operations donated the samples.In the reverse transcription-polymerase chain reaction(RT-PCR),the mRNA expression of LIF was mea- sured by semi-quantity analysis and the location of LIF protein was determined by enzyme-linked immunosorbent assay (ELISA).Results A slight expression of LIF was seen in normal cartilage but less in synovium.However,the expression of LIF was remarkable in synovial lining cells,superficial and middle layers of cartilage in animal os- teoarthritis.There was a significant difference in expression between the animal osteoarthritis and the control group (P＜0.05 ).In human tissue study,LIF mRNA was expressed to a very low level in normal articular tissues and there was no significant difference(P＞0.05)between different anatomical locations.In moderate degrading sub- chondral bone,LIF mRNA was expressed to its highest level.LIF was expressed to the highest level in seriously degrading cartilage tissues.The results were similar to ELISA testing results.LIF extents varied in different articular tissue sections.Conclusions LIF is an important mediator that can contribute to tbe pathogenesis of OA.The different temporal and spatial distributions of LIF in normal and OA tissues imply that LIF may play some important roles in pathogenesis of OA.

A PCR method was used to amplify the sequence encoding the mature peptide of?-mannanase of Bacillus subtilis. The gene was inserted into the Pichia pastoris vector pPIC9K, downstream of?-factor signal peptide sequence. The resultant recombinant plasmid pPIC9K-MAN was lineared by BglII digestion and introduced into the host Pichia pastoris GS115 by PEG method. After screen, the recombinant P. pastoris strain MAN22 was obtained and fermented in large scale 5L fermenter. The recombinant mannanase activity could reach to 1102IU/ml. The properties of the recombinant mannanase were characterized.