3.The Assembly of a Novel Enzyme Biosensor for Aflatoxin B_1 Detection
Da-Ling LIU ; Yi SHEN ; Jing ZHANG ; Dong-Sheng YAO ;
China Biotechnology 2006;0(03):-
A novel biosensor for aflatoxin B1 detecting has been reported. The biosensor electrode for AFB1 detecting was assembled by immobilized aflatoxin-oxidoreductase using open-ended multi-walled carbon nanotubes as matrix. Its linear range was between 0.16?M and 3.2?M. And if the specific anti-aflatoxin B1 antibody and aflatoxin oxidoreductase were both immobilized on the electrode with Multi-Walled carbon nanotubes, the detection limit of the modified electrode could be 16 nM with a 10 times improved sensitivity. The aflatoxin enzyme biosensor assembled this way strode one step forward its practical application.
4.Troubleshooting of bioinequivalence of compound valsartan tablets.
Da SHAO ; Yi-Fan ZHANG ; Yan ZHAN ; Xiao-Yan CHEN ; Da-Fang ZHONG
Acta Pharmaceutica Sinica 2014;49(4):524-529
The study aims to evaluate the bioequivalence of valsartan hydrochlorothiazide tablets, and to investigate the potential cause of bioinequivalence. This was a single-center study with an open, randomized double-way crossover design. Test and reference preparations containing 160 mg of valsartan and 25 mg of hydrochlorothiazide were given to 36 healthy male volunteers. Plasma concentrations of valsartan and hydrochlorothiazide were determined simultaneously by LC-MS/MS. The pharmacokinetic parameters and relative bioavailability were calculated, while the bioequivalence between test and reference preparations were evaluated. The dissolution profiles of test and reference preparations in four different mediums were determined via dissolution test and HPLC. The similarity was investigated according to the similarity factors (f2). The F(o-t) and F(0-infinity) were (139.4 +/- 65.2)% and (137.5 +/- 61.2)% for valsartan of test preparations. It led to get the conclusion that test and reference preparations were not bioequivalent for valsartan. A significant difference was observed between test and reference tablets in the valsartan dissolution test of pH 1.2 hydrochloric acid solution. The key factor of the bioinequivalence might be that dissolution of valsartan in acid medium has marked difference between two preparations.
Administration, Oral
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Adolescent
;
Adult
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Angiotensin II Type 1 Receptor Blockers
;
administration & dosage
;
adverse effects
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blood
;
pharmacokinetics
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Antihypertensive Agents
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administration & dosage
;
adverse effects
;
blood
;
pharmacokinetics
;
Area Under Curve
;
Chromatography, Liquid
;
Cross-Over Studies
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Drug Liberation
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Humans
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Hydrochlorothiazide
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administration & dosage
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adverse effects
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blood
;
pharmacokinetics
;
Male
;
Tablets
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Tandem Mass Spectrometry
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Therapeutic Equivalency
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Valsartan
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administration & dosage
;
adverse effects
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blood
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pharmacokinetics
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Young Adult
5.Isolation and differential expression of a novel MAP kinase gene DoMPK4 in Dendrobium officinale.
Gang ZHANG ; Yi-Min LI ; Ben-Xiang HU ; Da-Wei ZHANG ; Shun-Xing GUO
Acta Pharmaceutica Sinica 2014;49(7):1076-1083
Mitogen-activated protein kinases (MAPKs) are important signaling transduction components well conserved in eukaryotes and play essential roles in various physiological, developmental and hormonal responses in plant. In the present study, a MAPK gene, designated as DoMPK4 (GenBank accession No. JX297597), is identified from a rare endangered medicinal orchid species D. officinale using the reverse transcription polymerase chain reaction (RT-PCR) and rapid amplification of cDNA ends (RACE) methods. The full length cDNA of DoMPK4 is 1 518 bp in length and encoded a 369 aa protein with a molecular weight of 42.42 kD and an isoelectric point of 5.55. DoMPK4 protein contained a serine/threonine protein kinase active site (158-170), a MAP kinase site (71-174), and eight conserved motifs. DoMPK4 had a transmembrane (214-232) but no signal peptide. Multiple sequence alignment showed that DoMPK4 shared high identities (74.9%-80.6%) with MAPK proteins from various plants. Phylogenetic analysis demonstrated that DoMPK4 belonged to group A of the MAPK evolutionary tree, and is closely related to monocots. Real time quantitative PCR (qPCR) analysis revealed that DoMPK4 is differentially expressed among the five organs including leaf, stem, root, seed, and protocorm-like body (PLB). The transcription level of DoMPK4 is the highest in the PLBs with 17.65 fold, followed by seeds, roots, and stems with 5.84, 2.28, and 1.64 fold, respectively. The progressive enhancement of DoMPK4 transcripts in the developing PLBs compared to that in the germinating seeds, suggests a role of DoMPK4 during the development of embryogenic PLBs formation in D. officinale.
Amino Acid Sequence
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DNA, Complementary
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genetics
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DNA, Plant
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genetics
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Dendrobium
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enzymology
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genetics
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Gene Expression Regulation, Plant
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Mitogen-Activated Protein Kinases
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genetics
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metabolism
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Phylogeny
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Plant Leaves
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metabolism
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Plant Proteins
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genetics
;
metabolism
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Plant Roots
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metabolism
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Plant Stems
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metabolism
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Seeds
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metabolism
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Sequence Alignment
6.Cloning and expression analysis of a zinc-regulated transporters (ZRT), iron-regulated transporter (IRT)-like protein encoding gene in Dendrobium officinale.
Gang ZHANG ; Yi-Min LI ; Biao LI ; Da-Wei ZHANG ; Shun-Xing GUO
China Journal of Chinese Materia Medica 2015;40(1):42-47
The zinc-regulated transporters (ZRT), iron-regulated transporter (IRT)-like protein (ZIP) plays an important role in the growth and development of plant. In this study, a full length cDNA of ZIP encoding gene, designed as DoZIP1 (GenBank accession KJ946203), was identified from Dendrobium officinale using RT-PCR and RACE. Bioinformatics analysis showed that DoZIP1 consisted of a 1,056 bp open reading frame (ORF) encoded a 351-aa protein with a molecular weight of 37.57 kDa and an isoelectric point (pI) of 6.09. The deduced DoZIP1 protein contained the conserved ZIP domain, and its secondary structure was composed of 50.71% alpha helix, 11.11% extended strand, 36.18% random coil, and beta turn 1.99%. DoZIP1 protein exhibited a signal peptide and eight transmembrane domains, presumably locating in cell membrane. The amino acid sequence had high homology with ZIP proteins from Arabidopsis, alfalfa and rice. A phylogenetic tree analysis demonstrated that DoZIP1 was closely related to AtZIP10 and OsZIP3, and they were clustered into one clade. Real time quantitative PCR analysis demonstrated that the transcription level of DoZIP1 in D. officinale roots was the highest (4.19 fold higher than that of stems), followed by that of leaves (1.12 fold). Molecular characters of DoZIP1 will be useful for further functional determination of the gene involving in the growth and development of D. officinale.
Amino Acid Sequence
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Cloning, Molecular
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Dendrobium
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chemistry
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classification
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genetics
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metabolism
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Gene Expression Regulation, Plant
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Iron
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metabolism
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Membrane Transport Proteins
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chemistry
;
genetics
;
metabolism
;
Molecular Sequence Data
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Phylogeny
;
Plant Proteins
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chemistry
;
genetics
;
metabolism
;
Plants
;
chemistry
;
classification
;
genetics
;
Sequence Alignment
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Zinc
;
metabolism
7.Usefulness of Ankle Brachial Index to Predict the Extent of Coronary Stenosis
Shi-wei YANG ; Da-yi HU ; Xian WANG ; Shouyan ZHANG ; Jian ZHANG ; Shi GUO
Chinese Journal of Rehabilitation Theory and Practice 2006;12(6):461-463
ObjectiveTo examine the relationship between ankle brachial index (ABI) and the extent of coronary stenosis and evaluate the usefulness of ABI to predict the extent of coronary stenosis in old patients.Methods118 patients with coronary angiography were examined by ABI and hemostatic factors evaluation in addition to history collection.ResultsABI was inversely and significantly associated with Gensini score. ABI reduced significantly (P<0.001) in the patients with 3-vessel or left main coronary artery disease (CAD). But there were no significant differences in ABI among the patients with no CAD, 1-vessel or 2-vessel CAD. The corresponding area under the ROC curve was 0.75±0.045, with 95% CI=0.67~0.84 (P<0.001) in ABI in 3-vessel or left main CAD. When ABI≤0.9, it had a relatively high specificity (89.1%) and sensitivity (55.6%) for predicting the presence of 3-vessel disease or left main CAD.ConclusionIn the old patients, ABI is inversely and significantly associated with the extent of coronary stenosis, and ABI≤0.9 has a relatively high specificity and sensitivity for predicting the presence of 3-vessel or left main CAD.
8.Expression of SDF-1 gene in bone marrow mesenchymal stem cells of patients with myelodysplastic syndrome.
Journal of Experimental Hematology 2006;14(2):281-284
This study was aimed to investigate the expression level of stromal cell derived factor-1 gene (SDF-1) in bone marrow mesenchymal stem cells (MSC) of patients with myelodysplastic syndrome (MDS). The MSC from bone marrow samples of MDS patients were isolated, cultured and expanded, the morphology and immunophenotype of MSC were analyzed. The expression levels of SDF-1 and internal reference GAPDH in MSC of MDS patients were detected by real-time quantitative reverse transcriptase polymerase chain reaction (RQ-RT-PCR) method and were compared with expression levels of healthy donors. The results showed that the expression levels of SDF-1 in MDS patients were significantly different from those in healthy donors (1.53 +/- 0.92 vs 5.51 +/- 0.99) (P < 0.01). SDF-1 gene expression levels in bone marrow MSC of MDS patients were significantly higher than that in MSC derived from healthy donors. It is concluded that the abnormal expression of SDF-1 gene in MSC may influence the regulation of hematopoiesis of the bone marrow microenvironment in MDS patients and it is worthy of further investigation for new clue on etiological mechanism and treatment of MDS.
Adult
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Aged
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Bone Marrow Cells
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metabolism
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pathology
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Cells, Cultured
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Chemokine CXCL12
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biosynthesis
;
genetics
;
Female
;
Humans
;
Male
;
Mesenchymal Stromal Cells
;
metabolism
;
pathology
;
Middle Aged
;
Myelodysplastic Syndromes
;
genetics
;
metabolism
;
pathology
9.The enantioselective pharmacokinetic study of desvenlafaxine sustained release tablet in Chinese healthy male volunteers after oral administration.
Yin-xia CHEN ; Jiang-bo DU ; Yi-fan ZHANG ; Xiao-yan CHEN ; Da-fang ZHONG
Acta Pharmaceutica Sinica 2015;50(4):486-491
A chiral LC-MS/MS method for the simultaneous analysis of desvenlafaxine (DVS) enantiomers in human plasma was developed and applied to a pharmacokinetic study on 12 Chinese healthy volunteers. d6-Desvenlafaxine was used as internal standard (IS). Chromatographic separation was performed on the Astec Chirobiotic V chiral column (150 mm x 4.6 mm, 5 μm). The assay was linear over the concentration range of 0.500-150 ng x mL(-1) for both enantiomers (r2 > 0.99). The method was successfully applied to a stereoselective pharmacokinetic study of 100 mg desvenlafaxine sustained release tablets on 12 Chinese healthy volunteers under fasting conditions. The results showed that the pharmacokinetic parameters were similar to both enantiomers in Chinese healthy volunteers. The AUC(0-t), and C(max) of the two enantiomers were about 1.5 times higher than those of blacks and whites reported in the literature.
Administration, Oral
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Area Under Curve
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Asian Continental Ancestry Group
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Chromatography, Liquid
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Cyclohexanols
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blood
;
pharmacokinetics
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Delayed-Action Preparations
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Desvenlafaxine Succinate
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Dose-Response Relationship, Drug
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Healthy Volunteers
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Humans
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Male
;
Plasma
;
chemistry
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Stereoisomerism
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Tablets
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Tandem Mass Spectrometry
10.In vitro biological characteristics of mesenchymal stem cells from patients with myelodysplastic syndrome and their support to hematopoiesis.
Journal of Experimental Hematology 2005;13(5):839-842
To study the biological characteristics of mesenchymal stem cells (MSC) from patients with myelodysplastic syndrome (MDS) and their supportive capacity for hematopoiesis in vitro, MSCs from bone marrow samples of MDS patients were isolated, cultured and expanded. Morphology, immunophenotype, osteoblasts differentiative and proliferative property of MSC and colony forming unit-fibroblast (CFU-F) were measured and analyzed. Mononuclear cells (MNC) of cord blood were plated onto a feeder layer formed by MSC of MDS patient, cells count and CFU-GM production were observed. The results showed that the culture-expanded cells from MDS patients presented a typical fibroblast-like morphology. Cells were positive for SH2 (CD105), SH3 (CD73), Thy-1 (CD90), but negative for CD34 and CD45. After induction, these cells could differentiate into osteoblasts. Their proliferative capacity and CFU-F number were similar to those of MSC from healthy donors. The total cell count and CFU-GM yield in supernatants after culture for 2 weeks were significantly lower than those of control in hematopoiesis supportive experiments in vitro (P < 0.05). It is concluded that the biological characteristics of MSC from bone marrow of MDS patients are not different from those of MSC isolated from bone marrow of normal donors, however, their capacity of hematopoiesis support in vitro are significantly weaker.
5'-Nucleotidase
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analysis
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Adult
;
Aged
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Antigens, CD
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analysis
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Antigens, CD34
;
analysis
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Bone Marrow Cells
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cytology
;
immunology
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Cell Differentiation
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Endoglin
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Female
;
Hematopoiesis
;
Humans
;
Male
;
Mesenchymal Stromal Cells
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cytology
;
immunology
;
Middle Aged
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Myelodysplastic Syndromes
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blood
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Receptors, Cell Surface
;
analysis