1.The expression and significance of human macrophage metalloelastase in both gastric cancer cell lines and gastric cancer tissues
Hong ZHANG ; You-Ming LI ; Chun-Xiao CHEN ;
Chinese Journal of Digestion 1996;0(05):-
Objective To investigate the expression of human macrophage metalloelastase(HME) both in gastric cancer cell lines and gastric cancer tissues,and to find the role of HME in gastric carcino genesis.Methods Fifty eight patients who were operated in our hospital during April to Aug.2003 were enrolled.The samples taken from cancer,paracancer or normal tissues of these patients and cancer cell lines(MGC-803,SGC-7901,AGS)were detected for HME protein and HME mRNA expressions by Western blot and immunohistochemistry,RT-PCR and fluorescence quantitative PCR,respectively. Results Both HME mRNA and HME protein expressions were found in all three gastric cancer cell lines.The expressions of HME mRNA and HME protein in gastric cancer tissues was increased signifi- cantly compared with that in normal tissues(P0.05).Conclusions The increased HME expression in gastric cancer tissures compared with normal tissue indicate that HME may be a potential tumor marker for gastric cancer.
3.Surface display of phytase on Saccharomyces cerevisiae for efficient bioethanol production from corn starch.
Yan XIAO ; Xianzhong CHEN ; Wei SHEN ; Haiquan YANG ; You FAN
Chinese Journal of Biotechnology 2015;31(12):1700-1710
Production of bioethanol using starch as raw material has become a very prominent technology. However, phytate in the raw material not only decreases ethanol production efficiency, but also increases phosphorus discharge. In this study, to decrease phytate content in an ethanol fermentationprocess, Saccharomyces cerevisiae was engineered forheterologous expression of phytase on the cell surface. The phy gene encoding phytase gene was fused with the C-terminal-half region of α-agglutinin and then inserted downstream of the secretion signal gene, to produce a yeast surface-display expression vector pMGK-AG-phy, which was then transformed into S. cerevisiae. The recombinant yeast strain, PHY, successfully displayed phytase on the surface of cells producing 6.4 U/g wet cells and its properties were further characterized. The growthrate and ethanol production of the PHY strain were faster than the parent S. cerevisiae strain in the fermentation medium by simultaneous saccharification and fermentation. Moreover, the phytate concentration decreased by 91% in dry vinasse compared to the control. In summary, we constructed recombinant S. cerevisiae strain displaying phytase on the cell surface, which could effectively reduce the content of phytate, improve the utilization value of vinasse and reduce the discharge of phosphorus. The strain reported here represents a useful novel engineering platform for developing an environment-friendly system for bioethanol production from a corn substrate.
6-Phytase
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metabolism
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Biofuels
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Ethanol
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chemistry
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Fermentation
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Industrial Microbiology
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Saccharomyces cerevisiae
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metabolism
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Starch
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chemistry
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Zea mays
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chemistry
4.Investigations on biological functions of heat shock transcription factor 1 (HSF1) using a gene knock out mouse model
Xianzhong XIAO ; Guangwen CHEN ; Jialu YOU ; J.benjamin IVOR
Chinese Journal of Pathophysiology 2001;17(8):793-
HSF1 is the major heat shock transcription factor that binds heat shock element (HSE) in the promoter of heat shock proteins (HSPs) and controls rapid HSP induction in cells subjected to various stresses such as elevated temperature, chemicals, or exposure to toxins. Although at least four members of the vertebrate HSF have been cloned, details of their individual physiological roles remain relatively obscure. To clarify the exact in vivo functions of HSF1 and assess whether HSF1 exhibits redundant or unique roles, we have created homozygous Hsf1-/- mice using standard gene targeting techniques and isolated Hsf1-/- embryonic fibroblasts. Here we demonstrate that heat shock response (HSR) was not attainable in Hsf1-/- embryonic fibroblasts, and this response was required for thermotolerance and protection against heat-induced apoptosis, and that homozygous Hsf1-/- mice, which survived to adulthood according to genetic background, exhibited multiple phenotypes including: (1) placental defects that reduced embryonic viability after late midgestation (day 13.5); (2) growth retardation; (3) female infertility caused by preimplantation lethality, and (4) increased mortality (+/+ vs -/-, P<0.05) and exaggerated production of proinflammatory cytokine, TNF α (+/- vs -/-, P<0.05) after endotoxin challenge. Interestingly, although Hsf1-/- mice exhibited placental defects and embryonic death, basal HSP expression is not appreciably altered during embryonic development by the HSF1 null mutation, suggesting this factor might be involved in regulating some non-HSP genes or signaling pathways which may be important for development. Taken together, our results established direct causal effects for the HSF1 transactivator in regulating diverse physiological and pathophysiological conditions such as developnent, growth, reproduction, apoptosis and sepsis. The present work also provided a useful mammalian model for further investigating the implications of Hsf1 and its target genes (HSPs and other possible non-HSP genes) in various physiological and pathophysiological processes.
6.Isolation and Identification of Osmotolerant Yeast from "Swollen Can" Soy Sauce
You-Sheng OUYANY ; Xiao-Bao XIE ; Jiao-Di CHEN ; Hua XUE ; Yi-Ben CHEN ;
Microbiology 1992;0(04):-
Three osmotolerant yeasts were isolated from three batches of "swollen can" soy sauce produced by a Guangdong condiment plant. These strains grew faster in the media containing 50%~60% glucose or 15% NaCl than in common yeast media. The three yeasts were identified as Pichia etchellsii by using morphological characteristics, physiological and biochemical tests.
7.Pharmacokinetics of oleanolic acid liposomes in rats
Hongxuan CHEN ; Jiangxiu NIU ; Yanyu XIAO ; Zhipeng CHEN ; Ping HE ; Guoye YOU
Chinese Traditional Patent Medicine 1992;0(04):-
AIM: To study the pharmacokinetics of oleanolic acid liposomes in rats.METHODS: Oleanolic acid liposomes were prepared by ethanol injection-sonication;The pharmaceutical properties including morphology,encapsulation efficiency,particle size,zeta potential were determined.Rats were injected with oleanolic acid lipo-somes and oleanolic acid solution via the tail,respectively.The plasma concentrations of sample in rats were assayed by RP-HPLC.The pharmacokinetic parameters were computered by 3P97 program package.RESULTS: Oleanolic acid liposomes showed almost spherical,the mean diametre was(206.4 ? 4.7) nm.The encapsulation efficiency of oleanolic acid liposomes could be more than 90% based on orthogonal design,and no haemolyticus existed.The plasma concentration-time curves of the oleanolic acid liposomes conformed to a two-compartment model.T1/2? of oleanolic acid liposomes was(33.59 ? 12.53) min,AUC was(240.13 ? 23.62)(?g/mL.min),obviously higher than that of the control preparation.CONCLUSION: The oleanolic acid liposomes with high entrapment efficiency and even size has a good pharmacokinetic parameters by comparison with non-liposomes.
8.Rational Usage and Administration of Antibiotics in Polyclinics:A Cost-effectiveness Analysis
Min CHEN ; Wei-Jia YIN ; Tao-You ZHOU ; Fu QIAO ; Xiao-Ju LV ; Li-Ke LIU ;
Chinese Journal of Nosocomiology 1994;0(01):-
OBJECTIVE To enhance the rational usage of antibiotics by comprehensive interventional measures in clinics.METHODS Several interventional measures have been adopted in our hospital since January 2001: to(establish) expert team on antibiotics usage and administration consultation;constitute antibiotics use criteria(suitable) for each clinical specialty;train and examine the usage of antibiotics;censor the distribution of pathogen and drug-resistance variance.Then 10% of the discharged medical records in 2000,2002 and 2004 were drawn out respectively to analyze the usage of antibiotics and the isolation of pathogen from nosocomial infection cases.(RESULTS) The proportion of the patients with prophylactic and remedial indications was increased remarkably((P
9.Analysis on the risk factors associated with fungal infection following operation of gastrointestinal neoplasm
Yu-Feng YAO ; Zong-You CHEN ; Peng SUN ; Jian-Bin XIANG ; Xiao-Dong GU ; Duan CAI ;
Chinese Journal of Infection and Chemotherapy 2007;0(01):-
Objective To investigate the relevant risk factors for fungal infection following operation of the gastrointestinal neo- plasm and offer supporting data for the prevention of fungal infection.Methods Medical records from 116 patients who under- went the operation of gastrointestinal neoplasm in the special group of this hospital from January 2006 to June 2006 were retro- spectively reviewed on the relevant risk factors by univariate and multivariate Logistic regression analysis.Results Of the 116 patients reviewed, 18 had fungal infection.Forty-six samples were positive for fungal pathogen.The most frequently isolated fungal strain was Candida albicans (15/20) and the most common infection site was gastrointestinal tract (14/18).Fungal in- fection after the operation of gastrointestinal neoplasm was significantly relevant with the duration of antibiotic use, duration of post-operative fasting, low serum albumin, high blood glucose and complication of bacterial infection.The duration of antibiotic use was a significantly independent risk factor.Conclusions Reasonable antibiotic use, nutritional support, early enteral nutri- tion and control of blood glucose should be taken into account after the operation of gastrointestinal neoplasm in order to prevent fungal infections.
10.The Microorganism Constitutes Analysis of Soy Sauce Liquor from High-Salt-Level Watery State Fermentation
Xiao-Bao XIE ; You-Sheng OUYANG ; Hai-Yan ZENG ; Chun-Hua WANG ; Yi-Ben CHEN ;
Microbiology 1992;0(03):-
A system analysis about the microbial flora of normal and abnormal soybean sauce liquor from the high-salt-level watery state fermentation was made and the dominant bacteria and yeasts were identified.On the other hand,a discussion of effect of temperature on microbial flora was made.The results indicated that there were no obvious differences about the count of aerobe,spore-producing bacteria,enterobacteriaceae,lactic acid bacteria and anaerobe between the normal and abnormal soybean sauce liquor and there were marked differences about the count of yeasts and salt-tolerant bacteria.The predominant yeasts in normal soybean sauce were Torulopsis and Saccharomyces,accounting for 55.9% and 35.3% of the total yeasts separately,and in abnormal soybean sauce were Pichia,candida and Saccharomyces,accounting for 62.8%,17.9% and 9.0% respectively.