1.Determination of 7 Preservatives in Cosmetics in One Time by Gas Chromatography
Weiguang CHEN ; Yaling LIU ; Qing HAN
Journal of Environment and Health 1992;0(02):-
Objective To establish a method for determination of 7 preservatives, benzyl alechol, sorbic acid, benzoic acid, methyl-paraben, ethyl-paraben, propyl-paraben, butyl-paraben, in cosmetics in one time by gas chromatography. Methods The cosmetic sample was dissolved by methanol, extracted by ultrasonic and separated by packed column of DB1, the optimized experimental condition was explored also. Results The concentrations of 7 preservatives showed a positive correlation with the peak heights at the following ranges, 100-500 ?g/ml for benzyl alechol, 200-600 ?g/ml for sorbic acid, 25-500 ?g/ml for benzoic acid, methyl-paraben, ethyl-paraben, propyl-paraben and butyl-paraben, the correlative coefficients were 0.998 3-0.999 9. The detection limits were 5.5, 57.1, 29.6, 6.2, 5.5, 6.2, 6.2 ng/ml respectively. The recovery rates were 91.6%-102.7%. RSDs were 2.2%-10.2%. Conclusion The present method can perfectly separate the seven preservatives in cosmetics mentioned above with some advantages, such as simple, accurate, sensitive and quick.
2.Expression of human BTC with biological activity
han-bei, CHEN ; yan, DONG ; qing, SU
Journal of Shanghai Jiaotong University(Medical Science) 2006;0(02):-
Objective To obtain abundant human betacellulin(BTC) with biological activity. Methods The whole mature protein coding sequence of BTC gene was amplified by polymerase chain reaction(PCR) method applied to human pancreatic ?-cell tumors cDNA.The fragment was cloned into prokaryotic expression vector pET32a(+) plasmid.The recombinant plasmid was transformed into E.coli BL21 and the fusion protein was expressed under isopropyl-beta-D-thiogalactopyranoside(IPTG).The fusion protein was purified by Ni2+ affinity chromatography.SDS-PAGE and Western blot were employed to determine the expression and purification of the expected protein.BTC was added to culture NIH3T3 cells for 5 days,and cell proliferation was detected by MTT. Results Lots of fusion protein were produced,and the purified protein can stimulate the proliferation of NIH3T3 cells. Conclusion The human BTC can be successfully obtained from the pET32a(+) system with the biological activity of stimulating the proliferation of NIH3T3 cells.
3.Construction and expression of human PDX-1 eukaryotic expression vector
han-bei, CHEN ; yan, DONG ; qing, SU
Journal of Shanghai Jiaotong University(Medical Science) 2006;0(01):-
Objective To construct eukaryotic expression vector of human pancreatic duodenal homeobox 1(PDX-1) gene,and to detect its expression in NIH3T3 cell lines. Methods The whole coding sequence of PDX-1 gene was amplified by polymerase chain reaction(PCR) from human pancreatic-cell tumors cDNA.The fragment was inserted into eukaryotic expression vector pcDNA3.1 plasmid.The recombinant plasmid was verified by double digestion and DNA sequencing.The expression of PDX-1 gene in NIH3T3 cells was assayed by Western blot. Results The length of specific fragment amplified by PCR was 852 bp,and the recombinant plasmid pcDNA3.1-PDX-1 showed two bands of 5.5 kb and 852 bp by digestion using respective restriction enzymes BamHⅠand EcoRⅠ.The sequence of PDX-1 gene was approved or confirmed by blasting to GenBank.It was suggested that PDX-1 gene had been cloned into pcDNA3.1 vector correctly.Western blot showed that PDX-1 gene was expressed,which was detected 24 h after pcDNA3.1-PDX-1 plasmid was transfected into NIH3T3 cells. Conclusion The recombinant eukaryotic expression vector pcDNA3.1-PDX-1 was successfully constructed and expressed in NIH3T3 cell lines.
4.Determination of antibiotic residues in chicken meat using ultra-high-performance liquid chromatography coupled with hybrid quadrupole-orbitrap high-resolution mass spectrometry
PAN Xiaodong ; HAN Jianlong ; CHEN Qing
Journal of Preventive Medicine 2023;35(5):456-459
Objective:
To optimize the sample pretreatment and establish an ultra-high-performance liquid chromatography coupled with hybrid quadrupole-orbitrap high-resolution mass spectrometry (UPLC-Q-Orbitrap-MS) assay based on the parallel reaction monitoring (PRM) mode for determination of antibiotic residues in chicken meat.
Methods:
Blank matrix-spiked chicken meat samples were extracted with 95% acetonitrile aqueous solution containing Na2EDTA and formic acid. The extraction solutions were cleaned up using different combinations of C18, PSA and GCB fillers, and the combinations with a higher antibiotic recovery rate was screened. The residues of 32 antibiotics were determined using UPLC-Q-Orbitrap-MS based on the PRM mode.
Results:
If the extraction solution was cleaned up using the C18 filler, the largest number of antibiotics with a spiked recovery rate of >80% was seen, with matrix effects of 82.2% to 112.6%. The detection limits of 32 antibiotics were 0.8 to 5.8 μg/kg, with linear correlation coefficients of >0.99, spiked recovery rates of 71.3% to 111.5% and relative standard deviations of 3.2% to 14.2%.
Conclusion
The UPLC-Q-Orbitrap-MS assay is suitable for determination and quantitative analysis of multiple antibiotics in chicken meat.
Key words: high-resolution mass spectrometry orbitrap antibiotic residue parallel reaction monitoring
5.Influential Factors of Hearing Rehabilitation of Prelingually Deafened Children with Multichannel Cochlear Implant
Yi-qing CHEN ; Mo LONG ; Rui HAN
Chinese Journal of Rehabilitation Theory and Practice 2006;12(7):593-595
ObjectiveTo analyze the relative influential factors of hearing rehabilitation of the deafened children with multichannel cochlear implant. Methods42 prelingually deafened children who accepted multichannel cochlear implant were evaluated with their hearing ability, hearing thresholds and talent level, while their family and usage of the multichannel cochlear were investigated. Results and ConclusionThe result shows that the factors influencing the hearing rehabilitation are the occupations of the parents, income of the family, the time between diagnosing deaf and the operation, the time after the cochlear implant operation and the talent level. The results of the logistic regression show that the deafened children can gain their hearing developing rapidly if they living in a family with high income, their mothers have accepted more education, and they accepted longer time of continuing hearing-aid, etc.
6.Influential Factors of Hearing Rehabilitation of Prelingually Deafened Children with Multichannel Cochlear Implant
Yi-qing CHEN ; Mo LONG ; Rui HAN
Chinese Journal of Rehabilitation Theory and Practice 2006;12(7):593-595
ObjectiveTo analyze the relative influential factors of hearing rehabilitation of the deafened children with multichannel cochlear implant. Methods42 prelingually deafened children who accepted multichannel cochlear implant were evaluated with their hearing ability, hearing thresholds and talent level, while their family and usage of the multichannel cochlear were investigated. Results and ConclusionThe result shows that the factors influencing the hearing rehabilitation are the occupations of the parents, income of the family, the time between diagnosing deaf and the operation, the time after the cochlear implant operation and the talent level. The results of the logistic regression show that the deafened children can gain their hearing developing rapidly if they living in a family with high income, their mothers have accepted more education, and they accepted longer time of continuing hearing-aid, etc.
8.Evaluation of TAZ and KLF5 expression and their clinical significance in hepato-cellular carcinoma
Junren CHEN ; Dinghua YANG ; Yanhua SUN ; Qing HAN ; Minjie ZHANG
Chinese Journal of Immunology 2015;(3):380-383
Objective:To investigate the expression of TAZ and KLF5 and their clinical significance in hepatocellular carcinoma ( HCC).Methods:We freshly collected 76 samples of surgically resected HCC and matched normal tumor-adjacent tissues and detected TAZ and KLF5 expression in these samples using immunohistochemical staining.The clinical significance of TAZ and KLF5 protein expression were analysed.Results:The protein expression of TAZ and KLF5 in HCC tissues was significantly higher than those in matched normal tumor-adjacent tissues ( P=0.001;P=0.035 ).Clinicopathological analysis suggested that TAZ and KLF5 protein expression were associated with histopathological differentiation ( P=0.007;P=0.047 ) and TNM stage ( P=0.009;P=0.040).TAZ was positively correlated with KLF5 protein in HCC tissues (r=0.651,P=0.003).Conclusion:The high-expression of TAZ and KLF5 are correlated with poor clinicopathological characteristics,and TAZ is positively associated with KLF5 in HCC tissues, suggesting that TAZ may promote tumor progression through inhibition of KLF5 protein degradation in HCC.
9.Identification of Clostridium perfringens Causing Human Disease by Multiplex PCR
Yuhui ZHAO ; Weiling FU ; Ming CHEN ; Qing HUANG ; Han XIA
Chinese Journal of Nosocomiology 2005;0(11):-
OBJECTIVE To search a method for identifying Clostridium perfringens and genotyping their toxin for gene diagnosis by multiplex PCR.METHODS The mutiplex PCR was developed with three sets of primers(designed) based on the sequences of three C.perfringens toxin genes(CP?,CP? and CPE) published in GenBank to identify C.perfringens and genotype their three toxin genes.RESULTS Three expected(sequences) were (obtained) successfully by multiplex PCR and identified by electrophoresis.CONCLUSIONS The(specific) sequences of C.perfringens could be amplified and their three genes of toxins could be identified by this multiplex PCR(system).Such method should be helpful for developing gene diagnosis well.
10.Inflammatory stress induces insulin resistance in CD36 knockout mice
Xian CHEN ; Qing LIU ; Han LEI ; Hong LIU
Journal of Third Military Medical University 2003;0(09):-
Objective To explore whether the inflammatory stress can increase insulin resistance in the CD36 knockout (KO) mice.Methods After the mice were fed a standard chow for 14 weeks,oral glucose tolerance test,insulin release tests,lipids metabolism,SAA,IL-6,TNF-? and hepatic mRNA and proteins expression of mTOR,S6K,IRS-1,pIRS-1,2 were measured.Results Compared with the wide-type,the CD36 KO mice un-inflamed exhibited insulin resistance,and the insulin resistance index was increased[(3.01?1.24) vs (0.81?0.12),P