1.Effects of paeoniflorin on cerebral blood flow and the balance of PGI2/TXA2 of rats with focal cerebral ischemia-reperfusion injury.
Meng-Lin RAO ; Mi TANG ; Jin-Yue HE ; Zhi DONG
Acta Pharmaceutica Sinica 2014;49(1):55-60
This study is to investigate the effects of paeoniflorin on cerebral blood flow and the balance of PGI2/TXA2 of rats with focal cerebral ischemia-reperfusion injury. A total of 72 SD rats (3) were randomly divided into 6 groups: sham operation group, cerebral ischemia-reperfusion model group (I/R gourp), low (10 mg.kg-1), middle (20 mg.kg-1) and high (40 mg.kg-1) doses of paeoniflorin groups and nimrnodipine group. Focal cerebral ischemia in rats was made by inserting a monofilament suture into internal carotid artery for 90 min and then reperfused for 24 h. The effects of paeoniflorin on neurological deficit scores and the infarction volume of brain were detected. Relative regional cerebral blood flow (rCBF) was continuously monitored over ischemic hemispheres by laser-Doppler flowmetry (LDF). The expression of COX-2 in hippocampal CAl region was estimated by immunohistochemistry and the contents of prostacyclin I2 (PGI2), thromboxane A2 (TXA2), and ratio of PGIJ2/TXA2 in serum were measured by ELISA kits. Paeoniflorin significantly ameliorated neurological scores, reduced the infarction volume, and increased regional cerebral blood flow relative to the I/R group. In addition, paeoniflorin could inhibit COX-2 expression and the release of TXA2 and prevent the downregulation of PGI2 induced by I/R injury. The neuroprotective effects of paeoniflorin against focal cerebral ischemia-reperfusion rats might be attributed to improve the supply of injured hemisphere blood flow and adjust the balance between PGI2/TXA2.
6-Ketoprostaglandin F1 alpha
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blood
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Animals
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Brain
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blood supply
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CA1 Region, Hippocampal
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metabolism
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Cyclooxygenase 2
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metabolism
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Glucosides
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isolation & purification
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pharmacology
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Infarction, Middle Cerebral Artery
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blood
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metabolism
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pathology
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physiopathology
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Male
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Monoterpenes
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isolation & purification
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pharmacology
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Neuroprotective Agents
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isolation & purification
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pharmacology
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Paeonia
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chemistry
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Plants, Medicinal
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chemistry
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Random Allocation
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Rats
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Rats, Sprague-Dawley
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Regional Blood Flow
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drug effects
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Reperfusion Injury
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metabolism
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physiopathology
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Thromboxane B2
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blood
2.Analysis of correlations between blood lead levels and calcium, iron, zinc and environmental factors in children
Xing-yi, LU ; Lin, MENG ; Jin-yi, ZHONG
Chinese Journal of Endemiology 2008;27(4):458-460
Objective To investigate the current status of lead(Pb) poisoning in children and correlations between Pb levels and calcium(Ca), iron(Fe), zinc(Zn) and environmental factors. Methods ①Questionnaire survey was conducted among 3160 parents in Qingdao area, regarding factors that might have effects on the levels of Pb. ②Levels of blood Pb, Ca, Fe and Zn were determined by graphite furnace atomic absorption (GFAA) spectrometry for 3160 children, who were divided into three groups: mildly increased Pb levels, moderately increased Pb levels and severely increased Pb levels, and the effects of Ca, Fe and Zn on children's blood Pb levels were analyzed by multiple linear regressions.③Children having mildly Pb increase were divided into four groups and received Ca, Fe or Zn preparations or placebo. Results ① Children living with smokers, in new houses, in houses or kindergartens located in industrial areas or main traffic roads, consuming preserved eggs or canned drinks regularly were more easily poisoned.②Percentages of children with increased levels who had insufficient blood Ca, Fe and Zn : 53.31% (306/574), 46.17% (265/574) and 68.47% (393/574), respectively, in the group of children with mildly increased Pb levels; 57.68% (263/456), 49.34% (225/456) and 77.41% (353/456), respectively, in the group of children with moderately increased Pb levels; 64.71% (11/17), 58.82% (10/17) and 82.35%(14/17), respectively, in the group of children with severely increased Pb levels. In contrast, the percentages of children in the control group who had low blood Ca, Fe and Zn were 19.78%(418/2113), 5.21% (110/2113) and 14.62%(309/2113), respectively. ③The levels of Ca, Fe and Zn had a negative correlations with blood levels of Pb(coefficient of regression were-0.870,-0.430,-0.565, respectively). ④When given Ca, Fe and Zn, the children had the blood Pb levels decreased by 78.32% (112/143), 66.43% (95/143) and 67.83% (97/143), respectively. Conclusions ①Children's increased levels of Pb have adverse effects on the absorption of Ca, Fe and Zn. ②Intaking Ca, Fe and Zn preparations can reduce blood Pb level.
3.Validation of Microbial Limit Test for Levofloxacin Hydrochloride Gel
Jin WAN ; Meng LIN ; Wei XIE ; Wenqing WANG
Herald of Medicine 2015;(11):1486-1489
Objective To establish a microbial limit test for levofloxacin hydrochloride gel. Methods Ca2+ was added to neutralize the antibacterial activity of quinolone,and to form the insoluble precipitate by binding with carbomer, therefore destroying the stability of macromolecules in the gel. The microbial limit test for levofloxacin hydrochloride gel was confirmed combining with membrane filtration and plate methods. Results The normal plate counting was used in detecting the mold and yeast colony in the gel, the recovery was more than 70%.Simultaneously neutralization centrifugation and membrane filtration were used in bacterial count,with recovery less than 70%,and controlling bacteria test. Conclusion The method is accurate and practical for microbial limit test of levofloxacin hydrochloride gel, but is risky for bacterial counting and needs further risk assessment.
4.N-Glycans and intact glycopeptide-based characterization of N-glycosylation of monoclonal antibody drugs
Meng-lin LI ; Wen-wen ZHU ; Jin-lan ZHANG
Acta Pharmaceutica Sinica 2021;56(9):2360-2366
In recent years, the biopharmaceutical industry has grown rapidly, and the market size of monoclonal antibody drugs has increased significantly. Accurate structural characterization and quality control are the supporting technologies for the development of monoclonal antibody drugs. As a significant post-translational modification of antibody drugs, glycosylation has an important influence on its efficacy, stability, and immunogenicity. The existing literature usually uses liquid chromatography-mass spectrometry to perform major glycosylation modifications of monoclonal antibody drugs. Characterization, there are few studies on low-abundance glycosylation, but the characterization and control of low-abundance glycosylation cannot be ignored. In this study, we have established a qualitative and quantitative analysis technology for N-glycans based on RapiFluor-MS reagent-labeled monoclonal antibody drugs. This method has a short sample processing time and high sensitivity. It can not only characterize the main glycoforms of three monoclonal antibody drugs (adalimumab, bevacizumab, and trastuzumab) but also can quantify low-abundance N-glycans. The results of the study showed that the main glycoforms specified in the Pharmacopoeia could be detected in different batches of monoclonal antibody drugs, but the content of N-glycans in different batches of samples is not identical. After that, we analyzed the N-glycans connection sites and glycoforms at the intact glycopeptide level, further enriching the N-glycans structure information of the monoclonal antibody. The qualitative and quantitative analysis technology of N-glycans based on RapiFluor-MS reagent-labeled monoclonal antibody drugs can realize the in-depth characterization and control of glycosylation modification of monoclonal antibody drugs.
5.Development of mass spectrometry technique for quality assessment of monoclonal antibodies
Wen-wen ZHU ; Meng-lin LI ; Jin-lan ZHANG
Acta Pharmaceutica Sinica 2020;55(12):2843-2853
The research and development of monoclonal antibodies (mAbs) is a rapidly developing field. From the first generation of murine mAbs to the fourth generation of fully human mAbs, the efficacy and safety of mAbs in the treatment of various diseases have been continuously improved. In order to regulate the development and evaluation of mAbs, drug regulatory agencies and pharmacopeias of America and China have tried to issue feasible test procedures and acceptance criteria for quality evaluation of mAbs and biosimilars. Mass spectrometry (MS) technique with high sensitivity, resolution, selectivity, and specificity has become an important tool to evaluate the quality characteristics of monoclonal antibody-related products or specify mAb quality. The research of MS-based monoclonal antibody study involves structure characterization, impurity analysis, pharmacokinetics/pharmacodynamics (PK/PD), etc. This review focuses on the current quality control requirements of mAb related products and the development of MS technique for mAb quality characterization and specification. It is expected to provide information and references for evaluating the quality of monoclonal antibodies under research and development.
6.The Effect of Norcantharidin on Human Rectal Cancer Colo 320 Cells
Meng LI ; Tianyang WANG ; Cheng SHI ; Guojian ZHANG ; Lin LIN ; Jin ZHAO ; Pengtao REN ; Qinghui YAN
Journal of Kunming Medical University 2013;(9):20-24
Objective To investigate the effect of norcantharidin on growth inhibition and induction of apoptosis of human rectal cancer Colo 320 cells. Methods Norcantharidin (NCTD) in different concentrations were added to rectal cancer Colo 320 cells. Morphological characteristics of apoptosis were observed using the light microscope and transmission electron microscope. The expressions of Bag-1 and Bcl-2 proteins were tested by Western blotting. The growth inhibition of Colo 320 cells on the cell cycle was observed by flow cytometry. Results The apoptosis morphological changes of Colo 320 cells were observed by the light microscope and transmission electron microscopy. Flow cytometry analysis showed that the cell count of G2/M phase in experimental group was higher than that in control group ( <0.05) but the cell counts of G0/G1 and S phases have decreased in experimental group after treatment with NCTD at the concentrations of 5μg/mL, 10μg/mL and 20 μg/mL, and presented dosage dependence relations. The expressions of Bag-1 and Bcl-2 proteins have decreased. Conclusion Norcantharidin has inhibitory effect on rectal cancer Colo 320 cells, and the effect may be related to the cell cycle arrest and apoptosis.
7.Antitumor activity of recombinant antimicrobial peptide penaeidin-2 against kidney cancer cells.
Ming-Xiang, MENG ; Jian-Fang, NING ; Jing-You, YU ; Dan-Dan, CHEN ; Xiao-Lin, MENG ; Jin-Ping, XU ; Jie, ZHANG
Journal of Huazhong University of Science and Technology (Medical Sciences) 2014;34(4):529-34
Penaeidin-2 (Pen-2) is an important antimicrobial peptide derived from the Pacific white shrimp, Penaeus vannamei, and possesses both antibacterial and antifungal activities. Recent studies suggest that recombinant penaeidins show similar activities to the native Pen-2 protein. Previous researches have shown that some antimicrobial peptides (AMPs) exhibit cytotoxic activity against cancer cells. To date, there have been no studies on the antitumor effects of Pen-2. This study evaluated the potential of recombinant pen-2 (rPen-2) in the selective killing of kidney cancer cell lines ACHN and A498, and its action mechanism. MTT assays found the maximal growth inhibition of HK-2, ACHN and A498 cells treated with 100 μg/mL rPen-2 at 48 h was 13.2%, 62.4%, and 70.4%, respectively. DNA-specific fluorescent dye staining showed a high percentage of apoptosis on cancer cells. Flow cytometry revealed that the apoptosis rate of HK-2, ACHN and A498 cells was 15.2%, 55.2%, and 61.5% at 48 h respectively, suggesting that rPen-2 induced higher apoptosis rate in cancer cells than in HK-2 cells. Laser confocal scanning microscopy demonstrated that the plasma membrane was the key site where rPen-2 interacted with and destroyed tumor cells. Scanning electron microscopy showed the morphologic changes of the cell membranes of kidney cancer cells treated with rPen-2. These results suggest that rPen-2 is a novel potential therapeutic agent that may be useful in treating kidney cancers.
8.Development of Lateral-flow Immunoassay for WSSV with Polyclonal Antibodies Raised against Recombinant VP (19+28) Fusion Protein
Qing-yu, CHENG ; Xiao-lin, MENG ; Jin-ping, XU ; Wei, LU ; Jian, WANG
Virologica Sinica 2007;22(1):61-67
We have developed a sensitive and rapid lateral-flow immunoassay (LFIA) for WSSV,using colloidal gold as an indicator.The fusion protein,VP (19+28),was expressed in E.coli,purified and used to prepare polyclonal antibodies.The purified anti-VP (19+28) IgG were conjugated with colloidal gold.Unconjugated anti-VP (19+28) IgG and goat anti-rabbit IgG were immobilized on nitrocellulose membranes.After assembly,three groups (5 individual animals in each group) of shrimp samples were tested which included healthy,moribund and dead shrimps.For each group,three different tissues (body juices,gills and hepatopancreas) were tested at the same time.In parallel,all the samples were also analyzed using PCR for comparison.Out of 45 samples tested,30 were detected as positive while 15 were classified as negative.The results of LFIA correlate with those obtained by the PCR analysis,indicating that these two detection methods have the same efficacy in the limited number of samples tested in this preliminary study.
9.Support of acellular porcine corneal stroma for growth of corneal epithelium and stromal cell in vitro
Xu-Chu, LIN ; Yan-Nian, HUI ; Hao, MENG ; Yong-Jie, ZHANG ; Yan, JIN
International Eye Science 2008;8(7):1293-1295
AIM:To determine whether acellular porcine cornea stroma (APCS) could support the growth of the rabbit corneal cells in vitro.METHODS: APCS was prepared. The rabbit's corneal epithelium and stromal cells were cultured and seeded on, APCS in vitro.The observation of phase contrast photograph and histological examination were performed.RESULTS: Histological examination showed the epithe- lium grew on the scaffold of APCS in 2-3 layers at 10th day. The stromal cells adhered to the surface of the scaffold after 24 hours and invaded into the interlaminar of the material at 5th day.CONCLUSION: These results indicate that APCS can support the growth and proliferation of the corneal epithelium and stromal cells in vitro.
10.Denervation of the inferior alveolar nerve is associated with bone formation and bone mass maintenance in extraction sockets
Chengyong WANG ; Weihui CHEN ; Meng LU ; Jin WANG ; Chuanqing MAO ; Hai LIN
Chinese Journal of Tissue Engineering Research 2015;(42):6740-6745
BACKGROUND: There is a close relationship between innervations and bone formation and bone mass maintenance in the extraction sockets. OBJECTIVE:To study the possible effect of denervations on the regulation of new bone formation and bone mass maintenance in the extraction sockets. METHODS:The unilateral inferior nerve of dogs was sectioned to establish an animal denervation model. The normal side was used as control. After model establishment, the premolars of denervated side and normal side were extracted. Histological method was used to test new bone formation and bone mass maintenance in the extraction sockets at the 2nd, 4th, 8th and 12th weeks after tooth extraction. RESULTS AND CONCLUSION:The percentage of new bone areas in the extraction sockets was significantly lower in the experiment group than the control group at weeks 2, 4, 8 after tooth extraction (P < 0.01). The height difference between the buccal and lingual alveolar ridge was higher in the experimental group than the control group at weeks 2, 4, 8, 12 after tooth extraction (P < 0.05 or P < 0.01). These findings indicate that denervation is closely related with new bone formation and bone mass maintenance in the extraction sockets.