Microbial lipases have been widely used in traditional industries,as well as in emerging biocatalysed areas owing to their ability to catalyze a variety of reactions in aqueous and non-aqueous media.Therefore,it is very important to enhance amount of lipase production by recombinant overexpression for meeting market demand.A critical review of main and novel strategies which have been employed for recombinant expression of microbial lipases are presented,including codon optimization,fusion and co-expression,dual expression system based on hybrid promoters,homologous overexpression,cell surface displaying and high-throughput screening based on gene library of expression.These new technologies are gradually coming to the forefront in the recombinant expression of lipase,especially for cell surface displaying and high-throughput screening based on gene library of expression.Meanwhile,several recombinant expressions for representative microbial lipases were also introduced and discussed,which are available for consultation when attempting to overexpress any lipases by scientists and industrialists.

No abstract available.
Rectal Prolapse*

The fermentation conditions of lipase production by Geotrichum candidum Y162 were optimized. Initially, the most suitable carbon olive oil, nitrogen source soybean flour and NH4Cl, salt BaCl2 and MgCl2 were selected according to single factorial experiments respectively. Based on the result, screening methodology Plackett-Burman design was used to evaluate the effects of twelve factors related to lipase production and three statistically significant factors olive oil, BaCl2 and NH4Cl were selected. The path of steepest ascent was used to approach the optimal region of lipase production subsequently. Then, the optimal combined concentration for maximum enzyme activity were further optimized by response surface methodology and determined as follows: olive oil 2.35%, BaCl2 0.36%,and NH4Cl 4.69%.The optimization of culture conditions of G.candidum Y162 led to a 2.25-fold increase in lipase production relative to initial result 14.16 U/ml, which indicate that single factor in combination with response surface methodology is an effective method for optimization of lipase production conditions by G.candidum Y162.

Objective To study the effect of recombinant human growth hormone(rhgh) on the expressions of tumor necrosis factor a(TNFa) and endotoxemia in murine experimental obstructive jaundice(OJ) models.Methods Sixty adult male wistar rats.were randomly divided into three groups A: sham operation group(SO),20;B:OJ group,20;C: OJ+rhGH group,20.The rats in group OJ and OJ+rhGH suffered from bile duct ligation,while the SO group did not.Two weeks later,rats in OJ+rhGH group were injected with rhGH subcutaneously once a day.The dose was 0.75 Iu/kg.The other two groups were injected with the same amount of saline.The endotoxin(ETX),the liver function and TNFa were detected four weeks later.Result The level of ETX(0.036?0.010EU/m1) and TNFa(182.00?88.37lpg/ml) in OJ+rhGH were much lower than those in OJ group(0.065?0.011EU/m1 P

No abstract available.
Adenoids* ; Carcinoma, Adenoid Cystic* ; Maxillary Sinus*

Nevus lipomatosus cutaneous superficialis is a very rare skin disease, which usually is present at birth. The lesion shows groups of asymptomatic soft papules or nodules, which have a smooth or folded surface and are skin colored or yellowish. The area of predilection is the pelvic girdle (especially the buttock and sacrococcygeal areas). Microscopically, nevus lipomatosus cutaneous superficialis reveals groups of etopic fat cell nests within the dermis. Only one case was reported in Korea(1969). The authors observed a case of typical nevus lipomatosus cutaneous superficialis. The patient was 19 year-old male, who ha,ve had asymptomatic soft papules and nodules on the buttock, lower back and scalp since 14 years of his age. Routine laboratory findings were within normal limit. Histopathological findings showed etopic fat cell nests within mid and lower dermis (Fig. 3) Diagnosis was confirmed by clinical and histopathological findings. Litercature was briefly reviewed for the discussion.
Adipocytes ; Buttocks ; Dermis ; Diagnosis ; Humans ; Male ; Nevus* ; Parturition ; Scalp ; Skin ; Skin Diseases ; Young Adult

The production technology for the first generation of biofuels has been made great achievements and some countries, such as USA, EU countries, and Brazil, have formed successful biofuel industrial chains. Cellulose ethanol, a representative of the second generation of biofuels and a kind of more promising alternative fuels, has not yet got enough key technological breakthroughs and its large scale commercial production still needs rather some time to realize. Now it is in the early stage of transition to the second generation of biofuels. Taking the development of second generation of biofuels as their national policies, many countries have developed long-term development plans and objectives, and provided a good policy environment and strong support for it. Thus institutes and enterprises are engaging and successing in addressing key issues relating to the development of biofuels. At the mean time, some important issues relating to the sustainable development of biofuels have attracted people's attention.

Biomass resources are strategically vital for the sustainable development of a country.The United States has recently made a variety of plans or roadmaps and taken significant actions in order to promote the R&D of biomass resources.These plans and actions for the key issues in the development of biomass resources were analysed.

Objective To investigate whether the protein kinase C inhibitor can promote the apopto- sis of multidrug resistance tumor cell lines which are induced by chemotherapy drugs.Methods Choose the KB/S(oral squamous cancer cell line)and KB/VCR(its multidrug resistant cell line)to compare the Adri- amycin-induced apoptosis with or without staurospolin(protein kinase C inhibitor).The apoptosis is stained with acridine orange,tested by flow cytometry,and approved by electron microscope.Results 36 hours after the treatment with 0.04 ?g/ml adriamycin,apoptotic cells of KB/S are 96.68%,and after 48 hours,the apop- totic cells of KB/VCR are 64.99%.When the concentration of adriamycin are augmented to 0.4?g/ml and 2.0?g/ml,the apoptotic cells of KB/VCR are 69.74% and 37.18% respectively.When treated with stau- rospolin together,the apoptotic cells of KB/VCR increased to 72.58%(?~2=4.5,P0.05)respectively.These results were testified by electron microscope and acridine orange-stain.Conclu- sion The resistance to apoptosis may be one of the mechanisms of multidrug resistance and the protein ki- nase C inhibitor may reverse this resistance by promoting the apoptosis of multidrug resistance tumor cells.

Aim To study inhibitory effect of 5-fluorouracil encapsulated by galactosylceramide liposomes (5-Fu-GCL)on 5-Fu-resistent HepG_2 cells and its mechanisms. Methods Inhibitory effect of 5-Fu-GCL on established model of 5-Fu-resistant HepG_2 cells was assessed with MTT assay in vitro. The concentration-time course of 5-Fu-GCL in intracellular fluid was detected with high performance liquid chromatography (HPLC). Thymidylic acid synthase (TS) expression was observed with immunohistochemical method,and NO content was determined with chemical method. Results Obvious inhibitory effects of 5-Fu-GCL (75,150,300,600,1200?mol?L-1) on 5-Fu-resistant HepG_2 cells were observed with IC_ 50 of 158.6 ?mol?L-1,far lower than that of free 5-Fu (400.9 ?mol?L-1). 5-Fu-GCL (300 ?mol?L-1) inhibited 5-Fu-resistant HepG_2 cells in a time-dependent manner,and the inhibitory effect of 5-Fu-GCL was stronger than that of free 5-Fu during 12～48 h. Compared with free 5-Fu,5-Fu-GCL (300 ?mol?L-1) increased the content of intracellular fluid in 5-Fu-resistant HepG_2 cells. 5-Fu-GCL(62.5,300,1200 ?mol?L-1) not only inhibited the expression of TS,but also increased the production of NO in 5-Fu-resistant HepG_2 cells,and these effects of 5-Fu-GCL(300,1200 ?mol?L-1) were stronger than those of free 5-Fu. Conclusion 5-Fu-GCL has inhibitory effect on 5-Fu-resistant HepG_2 cells. The effect may be related to the increased concentration of 5-Fu-GCL in intracellular fluid,inhibited expression of TS and increased production of NO.