2.The primary study on the detection of sterigmatocystin by biologic enzyme electrode modified with the multiwall carbon nanotubes.
Dong-Sheng YAO ; Sheng-Mei WEN ; Da-Ling LIU ; Chun-Fang XIE ; Yan BAI ; Yan-Hong RAN
Chinese Journal of Biotechnology 2004;20(4):601-606
Sterigmatocystin (ST), the secondary metabolite of many kinds of filamentous fungi, is a potent carcinogen structurally related to the aflatoxins (AFT). With similar chemical structure, sterigmatocystion behaves much the homogeneous properties to aflatoxins, both of these mycotoxins exhibit similar biological properties due to their bisfuranoid structure. Since the common, and even heavier pollution, found in foods and feeds-stuff, sterigmatocystion is more harmful than aflatoxins. The reported detection methods of sterigmatocystion included the Thin-layer Chromatography, the High-Performance-Liquid Chromatography, the Enzyme-Linked Immunosorbant Assay and the PCR detection to the toxic gene, however studies about both easy and inexpensive electro-chemical methods have not been found. Our previous studies had discovered that Sterigmatocystin (ST) exist similar sensitivity towards aflatoxin-detoxifizyme (ADTZ), which we had isolated from a fungus, as aflatoxin does. In this work, the preliminary study on electrochemical analysis and determination of ST with triplet electrode enzyme-biosensor system (Ag/AgCl as the reference electrode, Pt and Au as the pair and work electrode, respectively) was carried out. Multiwall-carbon-nanotube (MWNT) had been used to increase the electron transportation on electrode. In the research, the Au electrode was modified by MWNT-immobilized ADTZ, and then the voltammertric behavior of ST was studied by means of cyclic voltammogram analysis and different pulse analysis. Autoprobe CP Research Atomic Force Microscope and TECNAI 10 Transmission Electron Microscope, had been used to detect the MWNT as well as the surface of MWNT-modified ADTZ. The voltammertric behavior of ST was studied by means of cyclic voltammogram analysis and different pulse analysis. The results show that the red-ox peak potential of ST is at the point of -600 mV, the linear detection range is from 8.32 x 10(-5) to 66.56 x 10(-5) mg/mL, the detection limit is at 8.32 x 10(-5) mg/mL, and the response time is 10 seconds. This study provided a good basic work for further research.
Biosensing Techniques
;
methods
;
Electrochemistry
;
Microscopy, Atomic Force
;
Microscopy, Electron, Transmission
;
Nanotubes, Carbon
;
chemistry
;
Sterigmatocystin
;
analysis
3.Molecular diagnosis of children with unexplained intellectual disability/ developmental delay by array-CGH.
Xi-Yu HE ; Xiao-Chun CHEN ; Ran LI ; Pei LI ; Ai-Mei LU
Chinese Journal of Contemporary Pediatrics 2015;17(5):459-463
OBJECTIVETo analyze the potential pathogenic genomic imbalance in children with unexplained intellectual disability (ID) and/or developmental delay (DD) and its association with phenotypes, and to investigate the value of array-based comparative genomic hybridization (array-CGH) in clinical molecular genetic diagnosis.
METHODSThe whole genome of 16 children with ID/DD was scanned by the array-CGH for detection of genomic copy number variations (CNVs), and the revealed genomic imbalance was confirmed by multiplex ligation-dependent probe amplification.
RESULTSG-band karyotyping of peripheral blood cells showed no abnormalities in the 16 children. The results of the array-CGH revealed that 6 (38%) of the 16 patients had genomic CNVs, and 3 cases of CNVs were normal polymorphic changes; 1 CNV was a microdeletion of 4p16.3, which was the critical region for Wolf-Hirschhorn syndrome, and 1 CNV was a microdeletion of 7q11.23, which was the critical region for Williams-Beuren syndrome. Moreover, a CNV was identified with two duplications at 2q22.2 and 15q21.3 in a boy, which proved to have a clinical significance due to its association with ID, brain DD, unusual facies, cryptorchidism, irregular dentition, etc.
CONCLUSIONSArray-CGH allows for the etiological diagnosis in some of the children with unexplained ID/DD. As a high-throughput and rapid tool, it has a great clinical significance in the etiological diagnosis of ID/DD.
Adolescent ; Child ; Comparative Genomic Hybridization ; methods ; Developmental Disabilities ; diagnosis ; genetics ; Female ; Humans ; Infant ; Intellectual Disability ; diagnosis ; genetics ; Male ; Multiplex Polymerase Chain Reaction
4.Determination of propofol in human serum by improved reversed phase high-performance liquid chromatography with fluorescence detection.
Ying-ying FAN ; Li-xian XU ; Ai-dong WEN ; Hui ZHANG ; Chun-ran LIU ; Wei LI ; Xiao-peng MEI
Journal of Southern Medical University 2006;26(10):1510-1512
OBJECTIVETo develop a new high-performance liquid chromatographic (HLPC) method for determination of propofol in human serum.
METHODSHuman serum samples were precipitated with 20% perchloric acid and centrifuged to obtain 50 microl of the supernatant for analysis by HPLC coupled with fluorescence detection. The analysis was performed with a C(18) reversed-phase column using a acetonitrile-water (90:10) phase delivered at 1.0 ml/min, with the excitation wavelength of 276 nm and emission wavelength of 310 nm.
RESULTSThe calibration curves were linear (r=0.997 5) within the concentration range of 0.05-10 microg/ml, the limit of propofol quantification was 50 ng/ml and the intra- and inter-day precisions were between -/+15%.
CONCLUSIONSThe method is accurate, sensitive and simple for propofol determination in clinical anesthesia.
Anesthetics, Intravenous ; blood ; chemistry ; Chromatography, High Pressure Liquid ; methods ; Fluorescence ; Humans ; Propofol ; blood ; chemistry ; Reproducibility of Results ; Spectrometry, Fluorescence ; methods
5.The effects of Mcl-1 gene on ATRA-resistant HL-60 cell.
Jin-rong FU ; Wen-li LIU ; Jian-feng ZHOU ; Han-ying SUN ; Miao ZHENG ; Mei HUANG ; Chun-rui LI ; Dan RAN ; Li LUO
Chinese Journal of Hematology 2005;26(6):352-354
OBJECTIVETo investigate the role of Mcl-1 gene in resistance of all-trans retinoic acid (ATRA) of leukemia cells.
METHODSLong-term, intermittent and repetitive exposure of HL-60 cells to ATRA was used to establish a multidrug-resistance cell line (HL-60/ATRA). HL-60/ATRA cells were transfected with Mcl-1 small interference RNA (siRNA) by Lipofectamine 2000. Western blot was used to detect the expression of Mcl-1. The proliferation, apoptosis and differentiation were evaluated by MTT assay, in situ nick end-labeling (TUNEL) and NBT assay, respectively.
RESULTSThe HL-60/ATRA could keep its undifferentiated and proliferative status to a high concentration of ATRA (100 nmol/L) with highly expressed Mcl-1 protein (relative grey scale 0.624 +/- 0.127). Mcl-1 gene knockdown by siRNA (relative grey scale 0.267 +/- 0.086) could reverse the resistance of ATRA of HL-60/ATRA by inhibiting proliferation, and inducing differentiation and apoptosis [apoptosis rate (18.5 +/- 4.5)%].
CONCLUSIONMcl-1 gene might be involved in ATRA resistance in HL-60 cells and inhibiting its expression could be a new approach to ATRA resistance reversion.
Apoptosis ; drug effects ; genetics ; Cell Differentiation ; drug effects ; genetics ; Cell Proliferation ; drug effects ; Drug Resistance, Neoplasm ; genetics ; HL-60 Cells ; drug effects ; metabolism ; Humans ; Proto-Oncogene Proteins c-bcl-2 ; genetics ; metabolism ; RNA, Small Interfering ; Tretinoin ; pharmacology
6.Biotransformation by human intestinal flora and absorption-transportation characteristic in a model of Caco-2 cell monolayer of d-corydaline and tetrahydropalmatine.
Yang-Zi LIU ; Xin-Bao YANG ; Xiu-Wei YANG ; Chun-Mei YAO ; Li RAN ; Shuai WU ; Wei XU ; Jian-Xun LIU
China Journal of Chinese Materia Medica 2013;38(1):112-118
OBJECTIVETo study the biotransformation by human intestinal flora, and the absorption and transportation characteristic in a model of human colon adenocarcinoma cell lines (Caco-2 cell) monolayer of d-corydaline (CDL) and tetrahydropalmatine (THP).
METHODCDL or THP was incubated with crude enzymes of human intestinal flora under the anaerobic environment and 37 degrees C conditions to transform CDL or THP. Caco-2 cell monolayer was used as an intestinal epithelial cell model for determination of the permeability of CDL or THP from apical side (AP side) to basolateral side (BL side) or from BL side to AP side. Transportation parameters and permeability coefficients (P(app)) were then calculated, and P(app) values were compared with the reported values for model compounds, propranolol as a well absorbed drug and atenolol as a poor absorbed drug. The concentration of CDL or THP was measured by HPLC coupled with photodiode array detector.
RESULTCDL or THP in the human intestinal flora incubation system did not happen biotransformation. In the Caco-2 cell monolayer model, the P(app) magnitudes of both CDL and THP were 1 x 10(-5) cm x s(-1) in the bi-directional transport, which were identical with propranolol. And their transports were concentration dependent between 0-180 min.
CONCLUSIONBoth CDL and THP may be stable in the human intestinal flora incubation system, and their absorption and transportation in the human Caco-2 cell monolayer model are mainly via passive diffusion mechanism.
Bacteria ; metabolism ; Berberine Alkaloids ; metabolism ; pharmacokinetics ; Biological Transport ; Biotransformation ; Caco-2 Cells ; Corydalis ; chemistry ; Drugs, Chinese Herbal ; metabolism ; pharmacokinetics ; Humans ; Intestinal Absorption ; Intestines ; metabolism ; microbiology ; Models, Biological
7.Excision repair cross complementation group 1 polymorphisms and lung cancer risk: a meta-analysis.
Chao CAO ; Yan-mei ZHANG ; Ran WANG ; Shi-fang SUN ; Zhong-bo CHEN ; Hong-ying MA ; Yi-ming YU ; Qun-li DING ; Li-hua SHU ; Zai-chun DENG
Chinese Medical Journal 2011;124(14):2203-2208
BACKGROUNDSeveral studies have evaluated the association between polymorphisms of encoding excision repair cross complementation group 1 (ERCC1) enzyme and lung cancer risk in diverse populations but with conflicting results. By pooling the relatively small samples in each study, it is possible to perform a meta-analysis of the evidence by rigorous methods.
METHODSEmbase, Ovid, Medline and Chinese National Knowledge Infrastructure were searched. Additional studies were identified from references in original studies or review articles. Articles meeting the inclusion criteria were reviewed systematically, and the reported data were aggregated using the statistical techniques of meta-analysis.
RESULTSWe found 3810 cases with lung cancer and 4332 controls from seven eligible studies. T19007C polymorphism showed no significant effect on lung cancer risk (C allele vs. T allele: odds ratio (OR) = 0.91, 95% confidence interval (CI) = 0.80 - 1.04; CC vs. TT: OR = 0.76, 95%CI = 0.56 - 1.02; CC vs. (CT + TT): OR = 0.96, 95%CI = 0.84 - 1.10). Similarly, there was no significant main effects for T19007C polymorphism on lung cancer risk when stratified analyses by ethnicity (Chinese or Caucasian). No significant association was found between C8092A polymorphism (3060 patients and 2729 controls) and the risk of lung cancer (A allele vs. C allele: OR = 1.03, 95%CI = 0.95 - 1.11; AA vs. CC: OR = 1.08, 95%CI = 0.88 - 1.33; AA vs. (AC + CC): OR = 1.08, 95%CI = 0.88 - 1.31).
CONCLUSIONWe found little evidence of an association between the T1900C or C8092A polymorphisms of ERCC 1 and the risk of lung cancer in Caucasian or Han Chinese people.
Asian Continental Ancestry Group ; genetics ; DNA-Binding Proteins ; genetics ; Endonucleases ; genetics ; Genetic Predisposition to Disease ; genetics ; Humans ; Lung Neoplasms ; genetics ; Polymorphism, Genetic ; genetics
8.Secondary injury in rats with intra-cerebral hematoma: a 7 Tesla high-field strength MRI study
Jun-Hai ZHANG ; Jian-Wen GU ; Fa-Bao GAO ; Rui XIA ; Tao YANG ; Yong-Qin KUANG ; XIAXun ; Yuan MA ; Jin-Min CHENG ; Bin KONG ; Hai-Dong HUANG ; Fan-Jun ZENG ; Min LU ; Chun-Mei RAN ; Yun-Ming LI
Chinese Journal of Neuromedicine 2012;11(6):586-589
Objective To dynamically analyze the evolutionary process of cerebral edema absorption and the level of local iron in rats with intra-cerebral hematoma by high-field strength 7 Tesla MRI and explore the characteristics and mechanism of secondary injury after intra-cerebral hematoma.Methods Sixteen adult SD rats (about 150 g) were randomly divided into experimental group (n=10) and control group (n=6).Rat models in the experimental group were established by performing injection of 50 μL their own venous blood into their right caudate nucleus accurately. Rats in the control group were used normal saline,instead.After that,head MRI (T2 and T2-star scans) was performed 1,2,3,7 and 14 d after the injection; their imaging features were compared. Results Nine rats in the experimental group survived and 1 died after the operation; in the early days (within 3 d), the T2 weighing imaging showed that the time of relaxation surrounding the hematoma was longer than that in control group,suggesting that the zone of the edema surrounding the hematoma became more clearly.In the early days (within 3 d),T2-weighted imaging was clear,and the time of relaxation surrounding the hematoma increased rapidly,steadily improved 3 d after the operation and reached its peak level 7 dafter the operation; the damage area absorption decreased steadily but turned widening 3 d later and reached the peak 7 d later.T2-star value reached the peak rapidly 3 d after the operation,and then,moderated the downturn.The rats in the control group showed no obvious signal changes under MRI,except those with needle tract injury. Conclusion Secondary injury after intra-cerebral hemorrhage shows a rapidly injury progress in the short terrn at first,and then,has intensify again after a stable period; the local iron diffusion trend is synchronized to the secondary injury,suggesting that iron may play a key role in the mechanism of secondary brain edema.
9.Screening results and genetic features of glucose-6-phosphate dehydrogenase deficiency in 54 025 preterm infants in Chengdu, China.
Zhou JIANG ; Mei WANG ; Li TANG ; Xiao-Li LI ; Chun-Rong LI ; Xin-Ran CHENG
Chinese Journal of Contemporary Pediatrics 2021;23(5):482-487
OBJECTIVE:
To analyze the screening results of glucose-6-phosphate dehydrogenase (G6PD) deficiency and gene mutation distribution of G6PD deficiency in preterm infants in Chengdu, China, in order to provide a basis for the improvement of G6PD screening process in preterm infants.
METHODS:
Fluorescent spot test for G6PD deficiency using dried blood spots was used for G6PD screening of 54 025 preterm infants born from January 1, 2015 to December 31, 2019 in Chengdu, and G6PD enzymology and gene detection were used for the diagnosis of 213 infants with positive screening results.
RESULTS:
Among the 54 025 preterm infants, 192 were diagnosed with G6PD deficiency, with an incidence rate of 3.55‰. The incidence rate of G6PD deficiency in preterm infants was higher than that in full-term infants in the same period of time and tended to increase year by year. Birth in summer, gestational age <32 weeks, and birth weight <2 500 g were influencing factors for the increase in false positive rate of screening (
CONCLUSIONS
Screening for G6PD deficiency in preterm infants should be taken seriously. It is recommended to apply cold-chain transportation of samples in summer to reduce the false positive rate of primary screening for G6PD deficiency. Genetic tests should be promoted in girls with positive screening results to improve the detection rate of G6PD deficiency in preterm female infants. There are various types of gene mutations in preterm infants with G6PD deficiency in Chengdu, and infants with c.1024C>T mutation tend to have mild conditions.
China/epidemiology*
;
Female
;
Genetic Testing
;
Glucosephosphate Dehydrogenase/genetics*
;
Glucosephosphate Dehydrogenase Deficiency/genetics*
;
Humans
;
Infant
;
Infant, Newborn
;
Infant, Premature
;
Mutation
10.Characteristics of immune function of full-term infants with different feeding patterns at the age of 3 months: a prospective cohort study.
Jing-Ran MA ; Zheng-Hong LI ; Wen-Juan ZHANG ; Chun-Li ZHANG ; Yu-Heng ZHANG ; Hua MEI ; Na ZHUO ; Hong-Yun WANG ; Dan WU
Chinese Journal of Contemporary Pediatrics 2021;23(10):1002-1007
OBJECTIVES:
To explore the characteristics of immune function of healthy full-term infants at the age of 3 months, and to analyze the relationship of immune function with feeding pattern and sex.
METHODS:
A total of 84 healthy full-term infants born in four hospitals in Beijing and Hohhot, China were prospectively recruited. Their feeding patterns remained unchanged within 4 months after birth. They were divided into a breast-feeding group and a milk powder feeding group according to their feeding patterns. At the age of 3 months after birth, peripheral venous blood samples of the two groups were collected to evaluate cellular immunity and humoral immunity and perform routine blood test. The laboratory indices were compared between infants with different feeding patterns and sexes.
RESULTS:
Compared with the milk powder feeding group, the breast-feeding group had significantly lower proportion of T cell second signal receptor CD28, immunoglobulin M, and proportion and absolute count of neutrophils (
CONCLUSIONS
Sex has no significant effect on the proportion of lymphocyte subsets in 3-month-old full-term infants, but feeding patterns are associated with the proportion of CD28
Breast Feeding
;
CD8-Positive T-Lymphocytes
;
Female
;
HLA-DR Antigens
;
Humans
;
Infant
;
Lymphocyte Activation
;
Male
;
Prospective Studies