Publications by authors named "Qingchun Liu"

19 Publications

  • Page 1 of 1

Evaluation of a Small-Molecule Compound, N-Acetylcysteine, for the Management of Bacterial Spot of Tomato Caused by Copper-Resistant .

Plant Dis 2021 Jan 11;105(1):108-113. Epub 2020 Nov 11.

Tropical Research and Education Center, Department of Plant Pathology, University of Florida, IFAS, Homestead, FL 33031, U.S.A.

Bacterial spot caused by spp. is one of the major diseases in tomato. is the main pathogen of bacterial spot on tomato in Florida. Currently, application of copper fungicides is the primary measure used to manage this disease. However, the development of copper resistance in and accumulation of copper in the environment are major concerns for excessive use of copper-based products in agriculture. Due to its antibacterial properties and low environmental impact, N-acetylcysteine (NAC), a small molecule commonly used in medicine for human bacterial diseases, has been studied in agriculture for the control of plant bacterial pathogens, including and . This study evaluated the effect of NAC alone and in combination with copper on a copper-resistant strain in vitro and its ability to control bacterial spot of tomato under greenhouse and field conditions. In vitro, the minimum inhibitory concentration of NAC against the strain was 2,048 mg liter. NAC increased sensitivity of the copper-resistant to copper in vitro when application of NAC was followed by copper application after 6 h. In greenhouse assays, NAC applied alone or in combination with copper significantly ( < 0.05) reduced the disease severity of bacterial spot on tomato compared with the untreated control. NAC at 100 mg liter + copper at 300 mg liter consistently exhibited synergistic effects against bacterial spot. In the field trials, NAC at 1,000 mg liter + copper at 150 mg liter significantly reduced disease severity compared with the untreated control. Results from this study demonstrated that NAC significantly reduced the disease severity of bacterial spot of tomato and enhanced the efficacy of copper against copper-resistant , indicating that NAC could be applied for the effective management of bacterial spot of tomato.
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http://dx.doi.org/10.1094/PDIS-05-20-0928-REDOI Listing
January 2021

Potential of a Small Molecule Carvacrol in Management of Vegetable Diseases.

Molecules 2019 May 20;24(10). Epub 2019 May 20.

Tropical Research and Education Center, Department of Plant Pathology, University of Florida, IFAS, Homestead, FL 33031, USA.

Carvacrol, a plant-derived volatile small molecule, is effective against various agents that can cause damage to humans, the food processing industry, and plants, and is considered a safe substance for human consumption. In this short communication, previous studies on the effectiveness of carvacrol against various agents, particularly plant pathogens and their associated mechanisms are described. In our study, carvacrol was found to be effective on media against several soilborne pathogens and in planta against three foliar pathogens (, , and ) of important vegetable crops in south Florida of the United States. Current research findings indicated that the effectiveness of carvacrol against various plant pathogens tested was associated with its direct bactericidal/fungicidal effect, which was affected greatly by its volatility. Development of new formulations to overcome the volatility and to prolong the effectiveness of carvacrol was also presented. Our studies on carvacrol suggested that, with advanced development of new formulations, carvacrol could be used as a promising tool in the integrated pest management for bacterial, fungal, and viral pathogens of important vegetable crops in Florida, the USA, and the world.
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http://dx.doi.org/10.3390/molecules24101932DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6572147PMC
May 2019

In vitro additive antitumor effects of dimethoxycurcumin and 5-fluorouracil in colon cancer cells.

Cancer Med 2017 Jul 2;6(7):1698-1706. Epub 2017 Jun 2.

Department of Colorectal Surgery, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, 310003, China.

Dimethoxycurcumin (DMC) is a lipophilic analog of curcumin, an effective treatment for colon cancer, which has greater chemical and metabolic stability. Chemotherapy treatments, such as 5-fluorouracil (5-Fu), play a key role in the current management of colon cancer. In this study, we investigated the antitumor efficacy of DMC in combination with 5-Fu in SW480 and SW620 colon cancer cells. CCK-8 assay was used to evaluate the inhibitory effect of DMC and 5-Fu on cancer cells proliferation, and the combination index was calculated. The influence of DMC and 5-Fu on cell cycle, apoptosis, reactive oxygen species (ROS) production, and mitochondrial membrane potential in SW480 and SW620 cells was determined using flow cytometry, and the related signaling pathways were detected by western blot. Transmission electron microscopy was used to observe endoplasmic reticulum expansion. DMC- and/or 5-Fu-induced apoptosis, stimulated G0/G1 phase arrest, increased ROS levels, decreased mitochondrial membrane potential, and enhanced endoplasmic reticulum expansion. The induction of apoptosis is involved in the increasing of Bax and cytochrome c and decreasing of Bcl2 expressions. Increased production of ROS was accompanied by upregulation of CHOP and Noxa. Combination therapy of DMC and 5-Fu had increased efficacy on the above pathways compared with either drug alone. Based on the calculated IC , combination treatment with DMC and 5-Fu had an additive antitumor effect in both cell lines. Combined treatment with DMC and 5-Fu led to an additive antitumor effect in colon cancer cells that was related to apoptosis induction, G0/G1 phase arrest, increased ROS production, decreased mitochondrial membrane potential, and enhanced endoplasmic reticulum expansion.
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http://dx.doi.org/10.1002/cam4.1114DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5504307PMC
July 2017

Isolation and characterization of two glutathione S-transferases from freshwater bivalve Anodonta woodiana: Chronic effects of pentachlorophenol on gene expression profiles.

Fish Shellfish Immunol 2017 May 21;64:339-351. Epub 2017 Mar 21.

State Key Laboratory of Environmental Chemistry and Eco-toxicology, Research Center for Eco-environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China. Electronic address:

Glutathione S-transferases (GST) play a prominent role in protecting cells against oxidative stress. Our previous study showed that the reactive oxygen species (ROS) generated from pentachlorophenol (PCP) could cause an acute impact on freshwater bivalve Anodonta Woodiana, but its chronic toxicity remain unclear. In order to investigate the chronic effect of PCP, clams A. Woodiana were randomly grouped into PCP treated group in which animals were administrated with 13.9 μg/L concentrations of PCP, and control group those with similar volume dimethyl sulfoxide. In addition, two complete GST sequences were isolated from A. Woodianaa and respectively named AwGST1 and AwGST2. The full-length cDNA of AwGST1 was consisted of a 5' untranslated region (UTR) of 132 bp, a 3' UTR of 80 bp and an open reading frame (ORF) of 609 bp encoding a polypeptide of 203 amino acids. The full-length cDNA of AwGST2 contained a 5' UTR of 57 bp, a 3' UTR of 291 bp and an ORF of 678 bp encoding a polypeptide of 226 amino acids. The constitutive expression levels of AwGST1 and AwGST2 were examined in different tissues including foot, mantle, adductor muscle, heart, hepatopancreas, hemocytes and gill. Administration of PCP could result in a significant increase of AwGST1 and AwGST2 expression in the hepatopancreas, gill and hemocytes. In the hepatopancreas, AwGST1 mRNA levels of PCP treated group increased more than 28.73% at day 1, then 70.37% (P < 0.05) at day 3, reach to 6.64 times (P < 0.01) at day 15 in contrasted with that of control group. AwGST2 increased more 18.18%, 82.88% (P < 0.05) and 2.43 times (P < 0.01) at day 1, 3 and 15, respectively. In the gill, AwGST1 expression showed a significant up-regulation in the PCP treated group during experiment observed compared with that of control group, mRNA level of AwGST2 increased more than 1.44 times (P < 0.05). In addition, expressions of AwGST1 and AwGST2 were significantly induced after PCP treatment in the hemocytes. These results indicated that up-regulations of AwGST1 and AwGST2 expression in bivalve A. woodiana are contribute to against oxidative stress derived from PCP treatment during experiment observed.
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http://dx.doi.org/10.1016/j.fsi.2017.03.039DOI Listing
May 2017

Congenital Heart Disease in Local and Migrant Elementary Schoolchildren in Dongguan, China.

Am J Cardiol 2016 Feb 18;117(3):461-4. Epub 2015 Nov 18.

Department of Cardiology, the Dongguan Affiliated Hospital of Medical College of Jinan University, the Fifth People's Hospital of Dongguan (also called Taiping People's Hospital of Dongguan), Guangdong, China.

The aim of this study was to determine the prevalence and treated status of congenital heart disease (CHD) in elementary schoolchildren and facilitate the long-term planning of health care, resource allocation, and development of targeted primary prevention strategies. From November 2011 to November 2012, 540,574 schoolchildren from 449 elementary schools were screened for CHD by trained doctors in Dongguan City. The schoolchildren who were suspected to have CHD were referred to a pediatric cardiologist and/or an echocardiographist for complete evaluation. Of them, 214,634 (39.7%) were local children and 325,940 (60.3%) were migrant children. The total prevalence of CHD was 2.14‰, and there was a significant difference (p <0.05) of the CHD prevalence between local (1.97‰) and migrant children (2.26‰). The treatment rates of CHD in local children and in migrant children were 63.51% and 47.21%, respectively (p <0.01). The commonest CHD was ventricular septal defect (43.13%), followed by atrial septal defect (25.84%) and patent ductus arteriosus (12.79%). With respect to gender, CHD was equally distributed between men and women. In conclusion, social, economic, and environmental risk factors that affect health of migrant children with CHD call for more attention from health policy makers and researchers in contemporary China. Efforts should be made to increase public health investment, establish health care manage system for children from migrant families, and increase the parents' awareness of preventing the CHD.
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http://dx.doi.org/10.1016/j.amjcard.2015.10.061DOI Listing
February 2016

Prevalence and clinical significance of cardiac murmurs in schoolchildren.

Arch Dis Child 2015 Nov 12;100(11):1028-31. Epub 2015 Jun 12.

Department of Cardiology, The Dongguan Affiliated Hospital of Medical College of Jinan University, the Fifth People's Hospital of Dongguan (also called Taiping People's Hospital of Dongguan), Dongguan, Guangdong, China.

Objective: To determine the prevalence and clinical significance of heart murmurs detected during heart disease screening among apparently healthy schoolchildren.

Design: Cross-sectional study.

Setting: 32 elementary schools in Dongguan City of China.

Patients: 81,213 schoolchildren aged 5-13 years from different elementary schools.

Main Outcome Measures: The prevalence and clinical significance of heart murmurs among schoolchildren.

Results: Murmurs were detected in 2193 schoolchildren (2.7%), of whom 215 had a structural heart disease (SHD). Of patients who had SHD, 198 children had congenital heart disease (CHD), 12 had mitral valve prolapse and 5 had rheumatic heart disease. In patients who had CHD, the most common diagnosis was a ventricular septal defect. With respect to sex, SHDs were equally distributed between males and females. Of the schoolchildren who had a murmur, 1797 (81.9%) had a murmur with the loudness of grade 1 or 2 and 396 (18.1%) had a murmur with the loudness of grades 3-6. The prevalence of SHD fell significantly with increasing age.

Conclusions: The study suggested that apparently healthy schoolchildren with grade ≤2 cardiac murmurs are least likely to have underlying SHD, especially in those aged ≥10 years. However, echocardiography should be performed in younger schoolchildren with cardiac murmur grade ≥3.
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http://dx.doi.org/10.1136/archdischild-2014-307819DOI Listing
November 2015

Cloning and molecular characterization of scorpion Buthus martensi venom hyaluronidases: a novel full-length and diversiform noncoding isoforms.

Gene 2014 Sep 25;547(2):338-45. Epub 2014 Jun 25.

Basal Medical College of Nanyang Medical University, Nanyang, 473041 Henan Province, China.

Hyaluronidase is a common component of scorpion venom and has been considered as "spreading factor" that promotes a fast penetration of the venom in the anaphylactic reaction. In the current study, a novel full-length of hyaluronidase BmHYI and three noncoding isoforms of BmHYII, BmHYIII and BmHYIV were cloned by using a combined strategy based on peptide sequencing and Rapid Amplification of cDNA Ends (RACE). BmHYI has 410 amino acid residues containing the catalytic, positional and five potential N-glycosylation sites. The deduced protein sequence of BmHYI shares significant identity with venom hyaluronidases from bees and snakes. The phylogenetic analysis showed early divergence and independent evolution of BmHYI from other hyaluronidases. An extraordinarily high level of sequence similarity was detected among four sequences. But, BmHYII, BmHYIII and BmHYIV were short of stop-codon in the open reading frame and poly(A) signal in the 3' end.
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http://dx.doi.org/10.1016/j.gene.2014.06.045DOI Listing
September 2014

Polymorphisms of HIF1A gene are associated with prognosis of early stage non-small-cell lung cancer patients after surgery.

Med Oncol 2014 Apr 25;31(4):877. Epub 2014 Feb 25.

Department of Thoracic Surgery, Tangdu Hospital, The Fourth Military Medical University, 569 Xinsi Road, Xi'an, 710038, China.

Hypoxia-inducible factor 1α (HIF1α) activates the transcription of genes that are involved in angiogenesis and cell survival. Over-expression of HIF1α caused by intratumoral hypoxia and its genetic alterations are associated with increased mortality in several cancer types including non-small-cell lung cancer (NSCLC). The aim of this study was to investigate the predictive role of single nucleotide polymorphisms (SNPs) in HIF1A gene in NSCLC outcomes. We genotyped two functional SNPs (rs2057482 and rs2301113) in HIF1A gene and assessed their associations with clinicopathological parameters and prognosis of 494 NSCLC patients by Cox proportional hazard model. There was no significant association between the SNPs and clinical outcomes of NSCLC for overall analysis. However, in stratified analysis for NSCLC patients at early stage (I/II), we observed a protective effect conferred by variant genotype of rs2057482 on overall survival (OS) (HR 0.42, 95% CI 0.22-0.80) and recurrence-free survival (RFS) (HR 0.60, 95 % CI 0.36-0.97) in a dominant model. Additionally, multivariate Cox analysis based on dominant model indicated that significant increased death and recurrence risks were observed in patients with early T-stage (T1 and T2) tumors, who carrying variant-containing genotype of rs2301113, as well as in patients without lymph node involvement (N0 stage) for rs2057482. Genetic variations on HIF1A gene are significantly associated with NSCLC outcomes in patients with early stage disease.
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http://dx.doi.org/10.1007/s12032-014-0877-8DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3971443PMC
April 2014

Transcatheter versus surgical closure of perimembranous ventricular septal defects in children: a randomized controlled trial.

J Am Coll Cardiol 2014 Apr 5;63(12):1159-1168. Epub 2014 Feb 5.

Department of Cardiovascular Surgery, Xijing Hospital, Fourth Military Medical University, Xi'an, China; College of Health Sciences, University of Wyoming, Laramie, Wyoming.

Objectives: The objective of this study was to evaluate the safety and efficacy of the surgical versus transcatheter approach to correct perimembranous ventricular septal defects (pmVSDs) in a prospective, randomized, controlled clinical trial.

Background: pmVSD is a common congenital heart disease in children. Surgical closure of pmVSD is a well-established therapy but requires open-heart surgery with cardiopulmonary bypass. Although the transcatheter approach is associated with significant incidence of complete atrioventricular block, it may provide a less invasive alternative. Critical comparison of the safety and efficacy of the 2 interventions necessitates a prospective, randomized, controlled trial.

Methods: Between January 2009 and July 2010, 229 children with pmVSD were randomly assigned to surgical or transcatheter intervention. Clinical, laboratory, procedural, and follow-up data over a 2-year period were compared.

Results: Neither group had mortality or major complications. However, statistical analysis of the 2 groups demonstrated significant differences (p < 0.001) in minor adverse events (32 vs. 7), quantity of blood transfused, duration of the procedure, median hospital stay, median intensive care unit stay, median hospitalization cost, and median blood loss. During a median follow-up of 2 years, the left ventricular end-diastolic dimension of both groups returned to normal and there was no difference in closure rate, adverse events, and complications between groups.

Conclusions: Transcatheter device closure and surgical repair are effective interventions with excellent midterm results for treating pmVSD in children. Transcatheter device closure has a lower incidence of myocardial injury, less blood transfused, faster recovery, shorter hospital stay, and lower medical expenses. (Transcatheter Closure Versus Surgery of Perimembranous Ventricular Septal Defects; NCT00890799).
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http://dx.doi.org/10.1016/j.jacc.2014.01.008DOI Listing
April 2014

Antioxidant and hepatoprotective effect of different extracts of guizhencao (herba bidentis bipinnatae) against liver injury in hyperlipidemia rats.

J Tradit Chin Med 2013 Aug;33(4):518-23

Basic Medicine College, Nanyang Medical University, Nanyang 473061, China.

Objective: To investigate the antioxidant and hepatoprotective properties of the different extracts Guizhencao (Herba Bidentis Bipinnatae) against liver injury in hyperlipidemia rats.

Methods: The rats were divided into 7 groups, with 10 rats in each. Rats were treated with high-fat diet for 18 weeks besides the normal control group, then rats in both normal control and model groups were received 5 mL/kg(-1) x day(-1) of saline and those in the positive control group with 2 mg/kg(-1) x day(-1) of lovastatin. Rats in the positive control group and different Guizhencao (Herba Bidentis Bipinnatae) extracts treatment groups (ethyl acetate extract group, n-hexane extract group, ethanol extract group, and aqueous extract group) were treated with corresponding extract at a concentration of 5 mL/kg(-1) x day(-1). After 8 weeks treatment, all rats were sacrificed and total blood samples were collected. Histological analysis of liver was underdone by hematoxylin and eosin. The levels of serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), glouse (GLU), cholesterol (TC), triglycerides (TG), low-density lipoprotein-cholesterol (LDL-C) and high-density lipoprotein-cholesterol were measured according to standard procedure using auto-analyzer. The superoxide dismutase (SOD) and malondialdehyde (MDA) levels in liver were ananlyzed by procedure instruction.

Results: The histopathological analysis implied that the administration of Guizhencao (Herba Bidentis Bipinnatae) extracts resulted in hepatoprotective role compared with that of the model group. In addition, the high-fat diet caused a remarkable increase of ALT, AST, GLU, TC, TG, LDL-C and MDA levels. A decline in HDL-C and SOD concentrations and a reversal of effects were observed in different Guizhencao (Herba Bidentis Bipinnatae) extracts groups, especially in the aqueous extract and ethanol extract groups.

Conclusion: The different extracts of Guizhencao (Herba Bidentis Bipinnatae) can play a protecting role against liver injury in hyperlipidemia rats maybe through decreasing ALT, AST, GLU, TC, TG, LDL-C and MDA levels and enhancing the liver anti-oxidative ability.
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http://dx.doi.org/10.1016/s0254-6272(13)60158-2DOI Listing
August 2013

The estrogenic effects of benzylparaben at low doses based on uterotrophic assay in immature SD rats.

Food Chem Toxicol 2013 Mar 5;53:69-74. Epub 2012 Dec 5.

College of Urban and Environmental Sciences, MOE Laboratory for Earth Surface Processes, Peking University, Beijing 100871, China.

Benzylparaben (BzP), a type of parabens being used as a preservative agent in cosmetics, food, and pharmaceutical products, may be ingested by humans. In this study, we performed an immature uterotrophic assay using Sprague Dawley (SD) rats by intragastric administration to determine the estrogenic effects of BzP and found significant increases in uterine weight with doses of 0.16 mg/kg body weight and higher (P<0.05). The in vivo estrogenicity of BzP was supported by in vitro results from the human estrogen receptor α (hERα)-coactivator recruiting assay and in silico molecular docking analysis performed in this study. The in vitro estrogenic activity of BzP can be observed at concentrations of 1.0×10(-8) M and higher. Molecular docking analysis showed that BzP fits well into the agonist pocket of hERα. The lowest observed effect dose (LOED) (0.16 mg/kg/day) of BzP is much lower than the documented LOEDs of other parabens. Actual risk may exist for people who consume a diet high in BzP or use BzP-laden cosmetics. In addition, we tested the sensitivity of Wistar rats to 17β-estradiol by immature uterotrophic assay, and no obvious uterotrophic response was observed in the rats given doses up to 100 μg/kg body weight.
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http://dx.doi.org/10.1016/j.fct.2012.11.043DOI Listing
March 2013

Sensitive and selective capillary electrophoretic analysis of proteins by zirconia nanoparticle-enhanced copper (II)-catalyzed luminol-hydrogen peroxide chemiluminescence.

Talanta 2012 Aug 10;97:193-8. Epub 2012 Apr 10.

College of Chemistry, Beijing Normal University, No. 19, Xinjiekou Wai Street, Beijing 100875, China.

We report herein a sensitive, selective, convenient CE determination of heme proteins in complex matrices by a sodium-dodecyl-sulfate-assisted, zirconia nanoparticle-enhanced copper (II)-catalyzed luminol-hydrogen peroxide chemiluminescence (CCLHPCL). Introducing a segment of sodium dodecyl sulfate to the capillary after sample injection not only rendered selective detection by quenching the luminescence signals from the non-heme proteins but also owning to the suppressed protein adsorption, led to significant improvement in separation efficiency and detection sensitivity. The signals were further improved by addition of ZrO(2) nanoparticles to the chemiluminescence solution. Compared with the conventional CCLHPCL, the detection limits (S/N=3) were improved by 10.2-22.0 folds, with 7.8×10(-9), 3.3×10(-9) and 1.5×10(-9) M for three model proteins, viz, myoglobin, hemoglobin and cytochrome C, respectively. Because the method did not require sophisticated pretreatment, it was convenient to analyze heme proteins in complex matrices, as demonstrated, hemoglobin in human blood and spiked human urine samples.
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http://dx.doi.org/10.1016/j.talanta.2012.04.016DOI Listing
August 2012

[Study on transportation of Xiaochaihu Tang in Caco-2 cell model].

Zhongguo Zhong Yao Za Zhi 2011 Apr;36(8):1087-90

Institute of Pharmacology and Toxicology, Key Laboratory of Biological Evaluation of Traditional Chinese Medicine Quality of the Administration of Traditional Chinese Medicine, Sichuan Provincial Key Laboratory of the Quality and Innovation Research of Chinese Materia Medica, Sichuan Academy of Chinese Medicine Sciences, Chengdu 610041, China.

Objective: To study the transportation of Xiaochaihu Tang in Caco-2 cell model.

Method: The safety concentration of Xiaochaihu Tang in Caco-2 cells was determined by MTT assay. Then the Caco-2 cell model was used to investigate the bi-directional transportation of Xiaochaihu Tang. The multicomponents of Xiaochaihu Tang and the influence of time were measured by high performance liquid chromatography (HPLC).

Result: The P(app) values of wogonoside and wogonin were (1.23 +/- 0.09) x 10(-6), (1.07 +/- 0.89) x 10(-5) cm x s(-1) from the AP side to BL side, and (2.12 +/- 0.19) x 10(-6) and (7.12 +/- 1.02) x 10(-6) cm x s(-1) from the BL side to AP side, respectively. The P(appAP --> BL)/P(app BL --> AP) ratio of wogonoside and wogonin were 0.58 and 1.49, respectively. Baicalin, baicalein and glycyrrhizic acid could not permeate the Caco-2 cell model.

Conclusion: The transportation of wogonoside and wogonin in Caco-2 cell model may be a passive transportation.
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April 2011

[Chemical constituents from aerial part of Atractylodes macrocephala].

Zhongguo Zhong Yao Za Zhi 2011 Mar;36(5):578-81

Department of Pharmacognosy, School of Pharmacy, Second Military Medical University, Shanghai 200433, China.

Objective: To investigate the chemical constituents from the aerial part of Atractylodes macrocephala.

Method: The constituents were isolated and purified by repeated column chromatography on silica gel, Sephadex LH-20 and ODS. Their structures were identified by physicochemical properties and spectrum analysis.

Result: Fourteen compounds were isolated and identified as atractylenolide I-III (1-3), 2-[(2E) -3, 7-dimethyl-2, 6-octadienyl]-6-methyl-2, 5-cyclohexadiene-1, 4-dione(4), 2, 6-dimethoxyphenol (5), scopoletin (6), 4-methoxycinnamic acid (7), caffeic acid (8), ferulic acid (9) protocatechuic acid (10), 3-hydroxy-1-(4-hydroxy-3- methoxyphenyl) propan-1-one (11), dictamnoside A (12), syringin (13), D-mannitol (14).

Conclusion: All the compounds were isolated from the aerial part of A. macrocephala for the first time and compounds 4, 5, 7-12, 14 were isolated from this species for the first time.
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March 2011

Cationic poly(amidoamine) dendrimers as additives for capillary electroseparation and detection of proteins.

Electrophoresis 2011 Jun 2;32(11):1302-8. Epub 2011 May 2.

College of Chemistry, Beijing Normal University, Beijing, 100875, P. R. China.

We examine the influence of cationic poly(amidoamine) (PAMAM) dendrimers on capillary electroseparation-UV analysis of proteins. PAMAMs adsorbing to the capillary surface suppressed the wall-adsorption of proteins; meanwhile, PAMAMs added to the buffer exhibited selectivity toward proteins. Presence of 3 x 10⁻⁴  g/mL PAMAM generation one (G 1.0) in 30 mM phosphate, at pH 2.6, rendered significant enhancement in separation efficiency; the merged peaks of myoglobin and trypsin inhibitor were separated. Moreover, the protein-dendrimer interactions changed the inherent UV absorbance profiles of proteins. UV-Vis study showed that the absorbance of cytochrome C and transferrin increased at the detection wavelength of 214 nm; their detection sensitivity enhanced by 2.44 and 2.01-folds, respectively, with addition of 5 x 10⁻⁴  g/mL PAMAM G 1.0.
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http://dx.doi.org/10.1002/elps.201000440DOI Listing
June 2011

[Simultaneous determination of five active constitutents in Xiaochaihu Tang by HPLC].

Zhongguo Zhong Yao Za Zhi 2010 Mar;35(6):708-10

Sichuan Academy of Chinese Medicine Sciences, Chengdu 610041, China.

Objective: To establish a HPLC-PDA method for the determination of baicalin, wogonoside, baicalein, wogonin and glycyrrhizic acid in Xiaochaihu Tang.

Method: A Symmetry Shield RP18 (4.6 mm x 250 mm, 5.0 microm) was used with a mobile phase of acetonitrile-0.01% H3PO4 in gradient elution. The detection wavelength was 251 nm,the flow rate was 0.45 mL x min(-1) and the column temperature was maintained at 30 degrees C.

Result: The accuracy, precision, sensitivity, specificity and linearity of this method met the requirements. The contents of the five effective fractions were determined simultaneously.

Conclusion: The method is rapid,simple and accurate and it can be suitable for the determination of baicalin, wogonoside, baicalein, wogonin and glycyrrhizic acid in Xiaochaihu Tang simultaneously.
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http://dx.doi.org/10.4268/cjcmm20100610DOI Listing
March 2010

CE determination of quinolones in the presence of bovine serum albumin.

J Sep Sci 2009 Jan;32(1):118-24

College of Chemistry, Beijing Normal University, Beijing, PR

This article describes the influence of bovine serum albumin (BSA) as an additive on the capillary electrophoresis-potential gradient determination of five quinolones, enoxacin, norfloxacin, ofloxacin, fleroxacin, and pazufloxacin. With 10 mg/L of BSA present in the buffer of 30 mM Tris and 3 mM phosphoric acid at pH 9, the detection limits of the five quinolones were in the range of 0.24-0.68 mg/L, i. e. 5.8-16.5-fold lower than those obtained with the buffer devoid of BSA, and the analysis time was shortened. We suggest that the inner wall-adsorbed BSA suppresses the adsorption of quinolones and simultaneously enhances the electroosmotic flow rate. Our experiments indicated that adopting the potential gradient detection technique could eliminate the interference of the UV-active proteins on the detection of quinolones that would occur with conventional optical detection, and therefore offer high detection sensitivity. As a demonstration, the method was applied to the determination of QNs in fortified chicken muscle sample with satisfactory results.
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http://dx.doi.org/10.1002/jssc.200800336DOI Listing
January 2009

Reactive block copolymer vesicles with an epoxy wall.

Langmuir 2007 Jan;23(2):790-4

State Key Laboratory of Polymer Physics and Chemistry, Joint Laboratory of Polymer Science and Material, Institute of Chemistry, The Chinese Academy of Sciences, Beijing 100080, China.

Recently, block copolymer vesicles have attracted considerable attention because of their properties in encapsulation and release. To explore their applications in biorelated fields, functionalization of the polymer vesicle is necessary. Herein, a reactive unilamellar vesicle is reported by self-assembly of poly(ethylene oxide)-block-poly(glycidyl methacrylate) copolymer (PEO-b-PGMA) in solution. When water was added into the PEO-b-PGMA solution in THF, unilamellar vesicles were produced. If hydrophobic primary amine additives, such as hexamethylenediamine (HDA) and dodecylamine (DA), were introduced during block copolymer assembling, the vesicular morphology remained unchanged; instead, the amines reacted with the epoxys and the vesicles were fixed by cross-linking. Furthermore, when 3-aminopropyl trimethoxysilane (APS) was applied, the organic/inorganic hybrid vesicles were obtained, which were stable against the solvent change. Therefore, this research not only supplies a new way to fix the vesicular morphology but also a reactive vesicle scaffold for introducing functional species.
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http://dx.doi.org/10.1021/la060766yDOI Listing
January 2007

[Value of right ventricular ejection fraction in the preoperative risk evaluation for pulmonary resection].

Zhongguo Fei Ai Za Zhi 2002 Apr;5(2):131-2

Department of Cardiothoracic Surgery, Maoming People's Hospital, Maoming, Guangdong 525000, P.R.China.

Background: To evaluate the preoperative right ventricular ejection fraction (RVEF) as a predictor of postoperative complications after lung resection.

Methods: RVEF was consecutively assessed in 254 patients before pulmonary resection by echocardiography. According to preoperative right ventricular function, the patients were divided into: group Ia (n=82, RVEF≥45%), group Ib (n=92,RVEF < 45%), group Ic (n=42, RVEF < 40%),and group Id (n=38, RVEF≤35%). Postoperative RVEF was detected again in 122 patients 3 weeks later after lung resection.

Results: Preoperative RVEF of patients with postoperative complications was significantly higher than that of patitents without postoperative complications (P < 0.001). Among group Ia, Ib, Ic, and Id, there were significant differences in postoperative morbidities (P < 0.005). Patients with a preoperative RVEF less than 40% had a higher incidence of complications than those with RVEF over 40% (P < 0.005). Of the 122 patients, postoperative RVEF was remarkably lower than preoperative RVEF (P < 0.01).

Conclusions: The preoperative RVEF may be a predictor of postoperative complications for lung resection. RVEF higher than 40% is considered as a safe range for pneumonectomy.
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http://dx.doi.org/10.3779/j.issn.1009-3419.2002.02.15DOI Listing
April 2002