1.Quality control and hot issues of maternal serum prenatal screening in China
Chinese Journal of Laboratory Medicine 2013;(1):1-5
It must be emphasized in the maternal serum prenatal screening that the quality is not only influenced by accuracy of biomarker assay,risk calculation parameters and biomarker database,but also influenced by clinical factors such as gestational weeks,weight and ect.The result of prenatal screening is just a risk evaluation,the subsequent diagnosis and the follow-up are more important.It is expected to improve screening efficiency by localization of prenatal screening database and making the quality management of the prenatal screening-diagnosis suitable for the national conditions.On the other hand,prenatal screening in the women of advanced maternal age and twin pregnancy,improve amniotic fluid cell culture method,chromosome analysis automation,the introduction and positioning of rapid prenatal molecular diagnosis techniques become the hot issues.
2.Construction of retrovirus vector containing rat cardiac myosin α heavy chain cDNA
Academic Journal of Second Military Medical University 2001;22(1):50-53
Objective: To clone rat cardiac myosin α he avy chain cDNA fragment encoding aa736-960 and construct its recombinant retrov irus vector(RV). Methods: The 681 bp target gene was amplified f rom heart tissue of young rats with RT-PCR, fusion gene of huIL-2/myosin was c onstructed by splicing with huIL-2 cDNA using ligation methods and its RV was constructed. RT-PCR and immunohistochemical assay were used to iden tify the expression of myosin protein in transfected cell. Results: The determination of nucleotide sequence showed that the nucleotide and ami no acid sequence of gene clone was the same as reported, its openin g reading frame was correct, the digesting result of pLNC-huIL-2-myosin was i dentical with the predicted. NIH3T3 cell was transfected with recombinant RV, and G418-resistant NIH3T3 cell was established.RT-PCR analysis indicated tha t mRNA of pLNC-huIL-2-myosin was present in cell transfected with RV. The im munohistochemical assay also showed that the myosin protein expression was highe r in the cell transfected with constructed RV. Conclusion: Rat cardiac myosin α heavy chain cDNA has been cloned and its RV has also been cons tructed and expressed in NIH3T3 successfully, it will contribute to research of prevention and treatment of heart immune injury by cardiac myosin gene transfer to induce specific tolerance.
3.Diagnostic value and clinical significance of 3D-CE-MRA in infantile superficial hemangioma
Fangxian Lü ; Wan Lü ; Haiqin WEN ; Shen CHEN ; Xueping ZHU
Journal of Practical Radiology 2014;(10):1723-1726
Objective To investigate the diagnostic value and clinical significance of the three-dimensional contrast-enhanced MR angiography (3D-CE-MRA)in the infantile superficial hemangioma.Methods Forty-four children with superficial hemangioma un-derwent conventional and dynamic contrast-enhanced MRI.MRI scanning was started at the time of inj ection,and four dynamic pha-ses of images were acquired continually.Maximum intensity proj ection (MIP)images were reconstructed to show the blood vessels of the lesions in multiple phases.Results Forty-nine infantile superficial hemangiomas were detected by MRI,including a single le-sion in 41 patients and multiple ones in 3.3D-CE-MRA showed 37 lesions in 32 patients,and other 12 lesions were not found in 12 patients.Conclusion The conventional and dynamic contrast-enhanced MRI can reflect the location,number and the range of the su-perficial hemangioma,and show the relationship between the lesion and the surrounding tissues.3D-CE-MRA directly shows the blood supply of the tumors.
4.Correlation between Homocysteine Levels and MTHFR C677T Gene Polymorphism of Cerebral inFarction
Guobao WANG ; Qundi SHEN ; Danping Lü
Journal of Medical Research 2017;46(5):154-158
Objective To study the correlation between homocysteine levels and MTHFR C677T gene polymorphism of cerebral infarction.Methods Four hundred and fifty patients with cerebral infarction in our hospital were selected as the study group from February 2012 to August 2015,including 181 diabetes patients and 269 non-diabetic patients.Also 285 cases of physical examination healthy people in the outpatient department were selected as the control group.The MTHFR C677T polymorphism and the correlation between genotype and Hcy levels were analyzed by pyrosequencing.Results The difference of distributions of MTHFR genotype between the study group and the control group was statistically significant (P < 0.05).The frequency of the T gene in the study group was significantly higher than the control group,the difference was statistically significant (x2 =13.67,P =0.00).The Hcy concentrations of the study group was significantly higher than the control group,and the difference was statistically significant (t =12.71,P =0.00).The Hcy levels of different MTHFR genotype in the cerebral infarction patients were statistically significant (F =17.68,P =0.00).Hcy levels in non-diabetic patients with cerebral infarction was significantly higher than in diabetic patients with cerebral infarction,and the difference was statistically significant (t =2.97,P =0.00).Hcy concentrations of TT genotype of non-diabetic group was significantly higher than the TT genotype of the diabetic group,CC type Hcy concentration significantly lower than the diabetic group,and the differences were statistically significant (t =5.67,2.18;P =0.00,0.03).In cerebral infarction patients both with non-diabetic and diabetic,the Hcy levels of MTHFR gene TT genotype were significantly higher than those of CC and CT genotype,and the differences were statistically significant (P < 0.05),and the differences of Hcy levels between the genotype of CT and CC was not statistically significant (P > 0.05).Conclusion The T allele frequency of MTHFR C677T in the cerebral infarction patients is much higher than healthy people.MTHFR TT genotype is related to serum Hcy levels.Maybe it is a risk factor for cerebral infarction.
5.Study on selective medium for isolation of Aspergillus fumigatus
Zehu LIU ; Xulian Lü ; Guixia Lü ; Yongnian SHEN ; Hongbin Xü ; Wei CHEN ; Suquan HU ; Weida LIU
Chinese Journal of Clinical Infectious Diseases 2008;1(1):34-37
Objective To investigate the growth inhibition of Aspergillns fumigatus by Candida albicans in vitro and to develop the selective medium for clinical isolation of Aspergillus fumigatus.Methods Aspergillus fumigatus and Candida albicans were single or co-cultured in sabouraud dextrose agar(SDA) medium and SDA broth in dark at 25 ℃,and fungal growth,pigmentation,as well as colony diameter weredocumented.Results ①The sensitivity of culture of Aspergillus fumigatus and Candida albicans on SDAplate was 100CFU/ml.②The growth of 106CFU/ml and 103CFU/ml Aspergills fumigatus was completely inhibited by 106CFU/ml Candida albicans.③Growth inhibition of Aspergillus fumigatus was correlated with the concentration of Candida albicans.④SDA containing 1 mg/L fluconazole inhibited growth of Candida albicans,and no Candida albicans was detected on SDA containing 5 mg/L and 25 mg/L fluconazole.Growth of Aspergillus fumigatus was partially inhibited on SDA containing 25 mg/L fluconazole.Conclusions Candida albicans can inhibit the growth of Aspergillus fumigatus in vitro.SDA containing 5 mg/L fluconazole can be used as the selective medium for the isolation of Aspergillus fumigatus.
6.Rapid identification of filamentous fungi by colony PCR
Xiaoli ZHANG ; Xuelian Lü ; Yongnian SHEN ; Guixia Lü ; Miaomiao WANG ; Yiping GE ; Weida LIU
Chinese Journal of Dermatology 2011;44(8):556-559
Objective To estimate the application value of colony PCR in the detection of pathogenic filamentous fungi. Methods Colony PCR was established and performed to amplify the internal transcribed spacer (ITS) region of 19 species (strains) of filamentous fungus followed by sequencing analysis. At the same time, DNA extracts from 8 of the 19 species of filamentous fungus were subjected to conventional PCR. Hha I and Hinf I endonucleases were used for restriction fragment length polymorphism (RFLP) analysis of the conventional and colony PCR products. Comparison analysis was carried out between the colony and conventional PCR. Results Of the 19 strains, 16(84.2%) yielded positive results by colony PCR; sequence analysis of the PCR products of ITS region revealed a 96% - 100% similarity with the reference sequence (NCBI database)of corresponding fungi. The amplification product length and RFLP profile of these products from the 8 species of filamentous fungus, except for those from Aspergillus nidulans, were consistent between the colony and conventional PCR. Conclusions Compared with conventional PCR, colony PCR-based detection of filamentous fungi is easy to operate, time and labor-saving, with high accuracy and reliability, and can be applied to the rapid identification of filamentous fungi.
7.Rapid identification of eight pathogenic filamentous fungi with PCR-RFLP analysis
Xiaoli ZHANG ; Xuelian Lü ; Yongnian SHEN ; Guixia Lü ; Miaomiao WANG ; Yiping GE ; Weida LIU
Chinese Journal of Dermatology 2010;43(8):523-525
Objective To develop a PCR-RFLP method to rapidly identify filamentous fungi causing deep infection. Methods Universal fungal primers were used to amplify the internal transcribed spacer (ITS) region of Aspergillus fumigatus, Aspergillus Bavus, Aspergillus terreus, Aspergillus niger, Aspergillus versicolor, Aspergillus nidulans, Scedosporium apiospermum and Fusarium moniliforme followed by restriction fragment length polymorphism (RFLP) analysis with restrictive endonucleases Hha I, Hae III, Hinf I, Taq I and Msp I. Then, 22 clinical and 2 environmental fungal isolates were identified with the developed PCR-RFLP method. Results The RFLP analysis of PCR products with restrictive endonucleases Hha I and Hinf I allowed discrimination of 8 filamentous fungi causing invasive infection, and it took only 1 day to carry out the whole procedure from DNA extraction to PCR and restriction digestion. The identification results of 22 clinical strains and 2 environmental isolates with this PCR-RFLP method were completely consistent with those with conventional morphological method. Conclusion PCR-RFLP analysis is an efficient method for rapid identification of cultured filamentous fungi.
8.Effect of electron transfer system on the hyphal formation of Candida albicans
Zehu LIU ; Xuelian Lü ; Xiaofang LI ; Guixia Lü ; Yongnian SHEN ; Min LI ; Weida LIU
Chinese Journal of Dermatology 2009;42(8):537-540
Objective To investigate the effect of electron transfer system on the hyphal formation of Candida albicans. Methods Candida albicans was cultured in RPMI 1640 supplemented with 10% new-born calf serum in 5% CO2 at 37 ℃ with or without the presence of inhibitors or activators of electron transfer system. Growth curve, morphology and percent of filamentation were observed for Candida albicans. MTT assay was used to assess the viability of Candida albicans. Results The solvents (chloroform and dimethyl sulfoxide) had no significant effect on the growth of and filamentation in Candida albicans. After incubation with thenoyltrifluoroacetone (TTFA) or benzhydroxamic acid for 24 hours, yeast cells of Candida albicans predominated in the culture. The growth of Candida albicans was significantly inhibited in log phase by the incubation with classic respiratory chain inhibitors such as rotenone, antimycin A, oligomycin, sodium azide, TTFA and sodium malonate, compared with the controls (all P < 0.01). Benzhydroxamic acid, an inhibitor of alternative oxidative pathway, also significantly inhibited the growth of Candida albicans in log phase (t = 10.92, P < 0.01). After incubation with rotenone, antimycin A, oligomycin, sodium azide, TTFA, sodium malonate, benzhydroxamic acid and disodium gnanylate, the percentage of filamentation in Candida albicans at 12 hours was 87.49 ± 0.52, 48.75 ± 4.44, 50.33 ± 8.50, 99.00 ± 1.00, 1.60 ± 0.53, 94.01 ± 0.99, 0.00 ± 0.00 and 92.33 ± 2.08, respectively, and the growth of Candida albicans at 7 hours was inhibited by (1.34 ± 0.15)%, (70.61 ± 1.02)%, (50.63 ± 5.38)%, (17.80 ± 7.89)%, (45.17 ± 1.27)%, (10.75 ± 3.62)%, (72.46 ± 1.14)% and -(5.96 ± 4.07)%, respectively. Conclusions Hyphal formation of Candida albicans could be suppressed by inhibitors of classic respiratory chain or alternative oxidative pathway, and is mainly regulated by alternative oxidative pathway.
9.Isolation and identification of Trichosporon inkin colonized in vagina
Xuelian Lü ; Huihua DAI ; Yaning MEI ; Xiaoli ZHANG ; Guixia Lü ; Yongnian SHEN ; Shuyu WANG ; Weida LIU
Chinese Journal of Dermatology 2009;42(8):525-528
Objective To report a case of vaginal colonization due to Trichosporon inkin. Methods A 34-year-old female presented with increased vaginal discharge accompanied by abnormal odor for 2 months. Clinical laboratory examination was carried out. Cultures of vaginal discharge yielded yeast-like colony. Subsequently, the isolate underwent the following mycological examinations: purification, slide micro-culture, temperature test, urea enzyme test, biochemistry identification, antifungal susceptibility test, and gene sequencing. Results Gynecological examination revealed white homogeneous secretions attached to mucous membrane of the vagina. Nugent scores of vaginal discharge amounted to 5-6. Two rounds of culture of vaginal discharge resulted in stramineous, reductus and yeast-like colony. The isolate could grow in 42 ℃. Appressorium on the top of hypha and typical sarcinae formed in slide microculture of corn agar, and yeast malt agar was the optimal growth medium for it. Urea enzyme test was positive. API 20C AUX biochemical test and gene sequencing revealed that the isolate was consistent with Trichosporon inkin. The isolate was sensitive to amphotericin B and azoles such as clotrimazole and fluconazole, but resistant to flucytosine and caspofungin. Conclusions It is the first report of vaginal colonization due to T. Inkin in China. The accu-rate identification of T. Inkin relies on synthetic analysis of phenotype characteristics, biochemistry test and molecular sequencing.
10.Expression of NF-κB gene and its significance in mouse hepatocellular carcinoma cell lines with differently lymphatic metastasis potentials
Xuening JI ; Xuejun FAN ; Mei LI ; Shen Lü ; Ruoyu WANG
Chinese Journal of Clinical and Experimental Pathology 2009;(6):624-627
Purpose To study NF-κB gene expression level in mouse hepatocellular carcinoma cell lines with differently lymphatic metastasis potentials and to discuss its roles in lymphatic metastasis.Methods Using real-time quantitative PCR, NF-κB gene expression level was detected in mouse hepatocellular carcinoma cell lines, including Hca-P with low lymphatic metastasis potential and Hca-F with high lymphatic metastasis potential.Results NF-κB mRNA expression in Hca-P and Hca-F cell lines were (1.41±0.48)×10~(-3),and (2.95±0.22)×10~(-3) (P<0.01),respectively.NF-κB mRNA expression levels were increased with metastasis potential.Conclusion NF-κB gene may play an important role in lymphatic metastasis of hepatocellular carcinoma.