Metabolism of n-alkane mainly includes ?-oxidation pathway and ?-oxidation pathway in Candida tropicalis,which are both catalyzed by a series of enzymes. The transformation from n-alkane to fatty acid is accomplished via ?-oxidation pathway,and the degradation of fatty acid is involved in ?-oxidation pathway. The mechanism on metabolism of n-alkane and studies on related enzymes are summarized in the review. Furthermore,some molecular genetics and metabolic engineering techniques related to Candida tropicalis developed in recent years are introduced.

Objective:To observe the effect of dexmedetomidine used in ophthalmic surgery anesthesia on the recovery quality in children. Methods:Totally 126 children with ophthalmic surgery were randomly divided into the control group and the observation group with the same induction program. The control group was given propofol with target controlled infusion during the operation, while the observation group was given dexmedetomidine 0. 6μg·kg-1 before the induction, and infused up in 10min, propofol with target controlled infusion was used during the operation, and stopped infusion 10min before the end of the operation. The cough number and degree, the occurrence of agitation and extubation time of the two groups were observed and compared during the anesthesia recovery period. Results:The cough incidence and agitation incidence was 36. 51% and 4. 76% in the observation group, respectively, which were significantly lower than those in the control group (74. 60% and 33. 33%, P<0. 05). The cough degree between the two groups showed significant difference (P<0. 05). The first cough time and the extubation time between the two groups showed no significant difference (P>0. 05). Conclusion:Dexmedetomidine used in ophthalmic surgery anesthesia of children can effectively control cough frequency and degree during the recovery period and reduce the agitation to improve the quality of clinical anesthesia recovery.

BACKGROUND:Transplantation of exogenous stem cells for functional cardiac celldeath or apoptosis easily induced complications after transplantation. Therefore, cardiac progenitor cells of heart itself have been ideal seed cells. OBJECTIVE:To establish stable celllines of cardiac progenitor cells from mouse heart, and to provide ideal cellmodels for studying proliferation and differentiation factors affecting cardiac progenitor cells during adult myocardial cells were damaged. METHODS:(1) Myocardiocytes were isolated from embryonic 15.5 days mice. (2) The cultured myocardiocytes were immortalized using retrovirus SSR69. Immortalized monoclonal myocardial cells were obtained using antibiotic selection and infinite dilution. (3) Monoclonal cellline with the property of cardiac progenitor cells was screened out. RESULTS AND CONCLUSION:(1) Myocardiocytes were successful y isolated and cultured. Partial cells showed obvious beating. (2) Myocardiocytes infected with retrovirus SSR69 were cloned and got 76 clones, then were named as CP15-#, (3) Screening the first 20 clones, the reasonable clones with the characteristics of cardiac progenitor cells were obtained according to myocardial cellmarker genes. The results suggested that immortalized cardiac progenitor cells were established mediated by reversible SV40 T antigen.

BACKGROUND:Nano-hydroxyapatite/bacterial celulose (nHA/BC) composite scaffolds prepared by nano-bionics method exhibit a structure and performance similar to natural bone. OBJECTIVE:To study the cytotoxicity and biocompatibility of nHA/BC composite scaffolds. METHODS:(1) Acute systemic toxicity test: nHA/BC leach liquor and normal saline were respectively injected intraperitonealy into Kunming mice. After 24, 48, 72 hours, the body mass of mice was recorded. (2) Sensitization test: nHA/BC leach liquor and normal saline were respectively injected subcutaneously into the back of Japanese white rabbits. With 72 hours of injection, edema and erythema were observed, and the experiment was done again at an interval of 14 days. (3) Pyrogen test: nHA/BC leach liquor and normal saline were respectively injected into the ear vein of Japanese white rabbits, and after injection, the body temperature of rabbits were determined. (4) Hemolysis test: Diluted rabbit anti-coagulant was added into nHA/BC leach liquor, normal saline and distiled water, respectively. (5) Passage 3 bone marrow mesenchymal stem cels from rabbits were co-cultured with nHA/BC materials, and then, cel proliferation, growth and adhesion on the material surface were observed. RESULTS AND CONCLUSION: nHA/BC composite scaffold was of no acute systemic toxicity, non-alergenic, no pyrogenic and hemolytic reactions; nHA/BC had a three-dimensional porous structure that was better for growth, proliferation and adhesion of rabbit bone marrow mesenchymal stem cels. These findings indicate that the nHA/BC composite scaffold has good biocompatibility and cytocompatibility.

Objective To study the probability of transferring the regulatory T cells induced by TGF-β1 to prolong the allograft survival and the mechanisms involved.Methods According to the different culture conditions.three experimental groups were established:control group(T cells from C57 BL/6 mice cultured with II-2),MLR group(T cells from C57BL/6 mice activated by alloantigen)and TGF-βgroup(T cells from C57BL/6 mice activated by alloantigen and cultured with 5.0 ng/ml TGF-β1).After the culture,the ratio of CI4+CD25+T and the Foxq3 expression were measured by FACS and RT-PCR,respectively.On 9th day,the pathologic analysis was performed and the ratios of TH1,TH2 and Treg and the proliferation of lymphocytes were measured.Results The ratio of CD4+CD25+T in TGF-β group was higher than that in control group and MLR group(P<0.05),and Foxp3 was expressed in CD4+CD25+T cell from TGF-βgroup.After transferring ofthe cells,the allografi survival time in TGF-β group was prolonged and its mean survival time(MST)was(22.8±1.9)d,which was longer than that in MLR group and control group (P0.05),lower than that of control group(P<0.05). And the ratio of CD4+CD25+T in TGF-β group was higher than that in control and MLR group obviously(P

To achieve higher level expression of Interferon α2b (IFN-α2b) in methylotrophic yeast (Pichia pastoris), a cDNA fragment coding for the mature IFN-α2b was designed and synthesized based on the synonymous codon bias of P. pastoris and optimized G+C content. The synthetic IFN-α2b was inserted into the secreted expression vector pPICZαA, and then integrated into P. pastoris GS115 genome by electroporation. Multi-copy integrants in the Mut+ recombinant P. pastoris strain were screened by high concentrations of Zeocin. 120 hours culturing allowed expression of the IFN-α2b transformant up to 810 mg/L as detected by SDS-PAGE and quantitative methods. In addition, Western blot analysis showed that the recombinant proteins had immunogenicity. The significant antiviral activity of the recombinant IFN-α2b protein was verified by WISH/ VSV system, which was 3.3×105 IU/mL.

Objective To investigate the osteoclast′s function levels in infants and toddlers and the relationship between the osteoclast function and sex,age,body length,body weight and body mass index(BMI).Methods Sixty-eight children(37 boys and 31 girls,aged from 1 to 36 months) were studied.All of the children were in good health.These children were divided as infants group and toddlers group according to their age.Just before the samples were collected,the children′s body weight,body length were measured and the BMI were calculated.Two biochemical markers,such as serum tartrate-resistant acid phosphatase 5b(TRAP5b) and urine deoxypyridinoline(DPD) were measured.Results The difference of serum TRAP5b concentration between infants and toddlers was significant at the level of P

Objective To assess the value of chest computer tomography (CT) and serum tumor marker in lung cancer screening among health check-up populations.Methods A total of 88 596 adults who had a medical check-up (including chest CT,chest DR,and tumor biomarkers test) in our center were enrolled in this investigation.Clinical diagnosis of lung cancer was confirmed by three professional doctors.Receiver operating characteristic (ROC) curve was used to assess the relationship between serum level of tumor biomarkers and lung cancer.Results The average detection rate of lung cancer was 59.8/100 000 in our center during 2007 and 2011 (men 42.9/100 000,women 92.2/100 000).Rate of positive results of chest CT was 94.3％,which was approximately 2 times of chest DR.Moreover,carcinoembryonic antigen (CEA) testing was effective in early diagnosis of lung cancer with higher sensitivity (73.6％) and specificity (57.1％).Conclusion This study suggests that health checkup centers should pay more attention to lung cancer screening in high risk populations,and new technologies might be used to facilitate the early diagnosis of lung cancer.

Objective To understand the infection situation of human T lymphocyte virus(HTLV) among blood donors in Zhongshan area.Methods Blood samples from 40 874 blood donors in Zhongshan from March to December 2016 were screened for HTLV antibody by using,enzyme linked immunosorbent assay(ELISA).The positive samples were reexamined two times,and specimens with positive results of reexamination were detected by using immunohistochemical method(CLIA).Then the positive samples were confirmed by Western blot(WB),and confirmed positive samples were judged as infection.Results Of all 40 874 cases of voluntary blood donors,21 cases were positive with HTLV antibody detected by ELISA,the positive rate of ELISA was 0.05%.Five cases were positive detected by CLIA method.One case was confirmed by WB,and the infection rate was 0.002 4%.Conclusion In order to ensure the safety of blood transfusion and reduce blood transfusion infection of HTLV,it might be necessary to perform HTLV screening in first-time blood donors in Zhongshan area.