1.Self-solidifying hydroxyapatite/norvancomycin composite for pulp capping
Xiao XU ; Junjun ZHAO ; Junli HAN
Chinese Journal of Tissue Engineering Research 2008;12(45):8973-8976
BACKGROUND: Hydroxyapatite has favorable biocompatibility, can protect pulp tissue and promote the formation of osteoid dentin and the concrescence of pulp tissue. However, hydroxyapatite has no capability of anti-infection. Increasing scholars deem that antibacterials should be added with the hydroxyapatite during the treatment of vital pulp conservation to elevate curative effects.OBJECTIVE: To observe the curative effects of self-solidifying hydroxyapatite/norvancomycin composite as pulp capping material and to make a comparison with calcium hydroxide.DESIGN, TIME AND SETTING: The present randomized controlled observation experiment was performed at the General Dental Clinic, the Ninth People's Hospital, Shanghai Jiao Tong University Medical College between January 2004 and June 2005.PARTICIPANTS AND MATERIALS: A total of 60 patients (60 teeth) that suffered from deep caries or pulp exposure, could return visit on time, and agreed to sign informed consents were selected for this study. These patients comprised of 28 males and 32 females, aged 9-40 years. Diagnosis criteria: Teeth with food impaction pain and/or caloric stimulation pain which can relieve after stimulation removal; in addition, with no spontaneous pain, radiating pain, and hypnalgia. Self-solidifying hydroxyapatite/2.5% norvancomycin composite were prepared in the Department of Dental Material, Shanghai Second Hospital. Self-hardening calcium hydroxide was provided by Dentsply Company, USA.METHODS: All 60 patients were randomly divided into an experimental group and a control group, with 30 patients (30 teeth) per group. Self-solidifying hydroxyapatite/2.5% norvancomycin composite and self-hardening calcium hydroxide were applied as pulp capping agents in the experimental and control groups, respectively. Pulpal tissue reactions were assessed after 8 weeks. Teeth with normal response were restored permanently, and the others were given root canal treatment.MAIN OUTCOME MEASURES: Pulpal tissue reaction of patients.RESULTS: In the experimental group, one case showed vague pain after 1-week pulp capping and received root canal therapy, with success rate of 97%. In the control group, two cases presented with vague pain after 3-day and 1-week pulp capping, respectively, and also received root canal therapy, with success rate of 93%.CONCLUSION: Self-solidifying hydroxyapatite/norvancomycin composite acquires a high success rate of pulp capping, with curative effects similar to calcium hydroxide, it is a good pulp capping agent for vital pulp preservation.
2.Determination of Ultratrace Copper in Barium Phosphate Laser Glass by Inductively Coupled Plasma Mass Spectrometry
Junjun XU ; Peng MEI ; Qiurong LI ; Taicheng DUAN ; Yongchun XU
Chinese Journal of Analytical Chemistry 2015;(1):27-32
With the use of high pure HF and HNO3 reagents, and autoclaves made of high purity Rerfluoroalkoxy ( PFA ) material, a solution sample digestion technique effective for phosphate samples, subjected to high temperature fusion, was established. The whole procedure was concise, fast and of low blank value. Key factors such as the amount and ratios of the reagents, the digestion temperature and time, were systematically optimized, it was found that within 0. 5 h at 150 ℃, only 1. 7 mL of total reagent consumption could lead to a complete sample decomposition. Most importantly, the samples were not required to be ground to fine powder, which greatly reduced the risk of contamination. In addition, an effective liquid_liquid extraction procedure based on 5_nonylsalicylaldehyde oxime as the extractant was established for matrix separation and analyte preconcentration. Under the optimal extraction conditions of 5 mL of 15% extractant, 0. 5% HNO3 of extraction acidity and 20% HNO3 of back_extraction acidity, a matrix separation efficiency of over 99. 999% could be realized and a preconctration factor of 10 could be obtained, which resulted in complete elimination of the matrix_induced interference and great enhancement of the analytical sensitivity. After optimization of the operation parameters of ICP_MS, high signal to background detection of Cu in 20%HNO3 at 840 W of plasma power and low sample uptake rate were realized. The detection limits of 2. 5 ng/g, RSD of 3. 3% for six detections of parallel samples, and the recovery of 94. 3% for spike test were obtained, respectively. The method was finally applied to three real samples analysis, and the results agreed well with the data from laser adsorption loss experiment.
3.The clinical investigation of ischemic tolerance of brain
Yanping WANG ; Xiaoling ZHANG ; Junjun HUANG ; Minchu ZHU ; Lizhen XU
Chinese Journal of Postgraduates of Medicine 2009;32(31):3-5
Objective To explore whether ischemic tolerance exists in patients of cerebral infarction following transient ischemic attacks (TIA). Methods Thirty-eight patients with cerebral infarction following TIA(with TIA group) and 98 patients with cerebral infarction without TIA (without TIA group)were studied. The positive expression rate of CD62P in platelet and the size of cerebral infarction on admission was measured. The scores of activities of daily living were evaluated on admission and after a month. Results The positive expression rate of CD62P in platelet was lower in with TIA group than that in without TIA group [ (4.21 ± 0.43 )% vs (6.01 ± 0.03)%,P< 0.05 ]. The area of cerebral infarction and the scores of activities of daily living were lower in with TIA group than those in without TIA group(P< 0.05 ). Conclusion Cerebral infarction following TIA has ischemic tolerance.
4.Clinical of distribution of 410 strains of Klebsiella pneumoniae and its drug resistance analysis in a hospital of Dongguan during 2012-2014
Mingkao XU ; Cailian XIE ; Junjun PAN ; Yali LEI ; Hua DU
International Journal of Laboratory Medicine 2016;37(7):920-922
Objective To investigate the drug resistance tendency of Klebsiella pneumoniae isolated from the clinical samples during 2012-2014 to provide reliable evidence for clinical treatment .Methods The Klebsiella pneumoniae strains isolated from the submitted specimens were collected and identified according to the national clinical test procedures ,and the drug sensitivity test was performed by using MIC method .The confirmation test of ESBLs was conducted by using K‐B method and the phenotype of carbap‐enemases producing was confirmed by using the improved Hodge test .Results Totally 410 strains of Klebsiella pneumoniae were i‐solated ,55 .87% of which were derived from sputum ,and the rest was derived from pus(9 .53% ) ,secretion(9 .47% ) and blood (8 .78% );Klebsiella pneumoniae was mainly originated from ICU ,respiration department and oncology department ,accounting for 16 .10% ,9 .02% and 7 .80% respectively ;the resistance rates of Klebsiella pneumoniae against imipenem was 0 .74% ,the resist‐ance rates of Klebsiella pneumoniae against ampicillin/sulbactam ,cafazolin ,cefepime ,cefotaxime ,cefatriaxone ,ceftazidine ,compound sulfamethoxazole were decreased year by year ,while which against amoxicillin/clavulanic acid showed the increasing trend as a whole .Conclusion Timely conducting the identification and drug susceptibility analysis on local Klebsiella pneumoniae and tracking its drug resistance trend can guide the rational and standardized use of antibacterial drugs ,reduces the pressure for selecting anti‐bacterial drugs in order to reduce the generation of drug resistant strains .
5.Fast Determination of Al Residue in Polyether Ketone Ketone by Graphite Furnace Atomic Absorption Spectrometry
Peng MEI ; Junjun XU ; Junfang GUO ; Taicheng DUAN
Chinese Journal of Analytical Chemistry 2014;(11):1702-1705
AnewmethodwasdevelopedforfastdeterminationofAlresidueinpolyetherketoneketone ( PEKK) special polymer material by graphite furnace atomic absorption spectrometry ( GF-AAS) . Instead of high temperature ashing, sample was dissolved in concentrated sulfuric acid and diluted by tetrahydrofuran, then was directly analyzed by GF-AAS. Systematical investigation was made on sample preparation, it was found that for 0. 2 g of sample weight, a clear sample solution could be obtained by heating at 220 ℃ with 2 mL of concentrated H2 SO4 for 4 min, and the obtained solution was ready for the subsequent mixing with tetrahydrofuran for sample dilution or dispersion before analysis. Redesign of the GF-AAS temperature program was also made, on the basis of the recommended program a pre-ashing step was added, which greatly helped increasing the analytical precision when the temperature was set at 400 ℃ and the total time was set at 40 s. The detection limits ( 3σ) were 38. 5 ng/g, the RSD for six parallel determinations of real samples was 2. 2%, and the recoveries for spiked tests were 99%-105%, respectively. In comparison with the traditional high-temperature ashing technique, the established method was more concise, faster and less exposed to contamination during sample preparation.
6.Binding capacity of aberrantly glycosylated serum IgA1 with human umbilical vein endothelial cells
Junjun ZHANG ; Feng YU ; Lixia XU ; Ying ZHANG ; Minghui ZHAO
Journal of Peking University(Health Sciences) 2004;0(02):-
0.05), respectively. Conclusion: IgA1 could bind to HUVEC directly, and the binding capacities of DesIgA1 and Des/DeGalIgA1 to HUVEC were significantly higher than that of normal IgA1. Serum IgA1, especially deglycosylated IgA1, might play some role in vascular lesions of IgAN.
7.Effects of macrophage metalloelastase on angiostatin generation and growth of tumor vessels in murine colon carcinoma
Zhangwei XU ; Jianming XU ; Hai SHI ; Qiao MEI ; Junjun BAO ; Yuxian SHEN
Chinese Journal of Digestion 2011;31(4):258-263
Objective To determine the pathway of macrophage metalloelastase (MME)generate active angiostatin by decomposing plasminogen and its effect on inhibiting growth of tumor and microvessel density (MVD) in vivo in mouse models. Methods The recombined plasmid pEGFPC1-MME was constructed. Thirty mice were subcutaneously inoculated with CT-26 cells that were stably transfected with pEGFP-C1-MME (MME-transfected group), 30 with CT-26 cells transfected with empty vector pEGFP-C1 (vector-transfected group) and 30 with CT-26 cells (non-transfected group). Radioiodination and radioisotope tracer were used to explore the pathway of angiostatin generation in vivo. Results SDS-PAGE electrophoresis analysis revealed that, in the PAGE gel contained the protein with molecular weights of 35 000 and 38 000, radioactivity in MME-transfected group was significantly higher than vector-transfected and non-transfected groups (P = 0. 00).Western blotting analysis demonstrated two bands containing 35 000 and 38 000 fragments in three groups. Quantification of the protein signals by image analysis revealed that the levels of 35 000 and 38 000 fragments were obviously increased in MME-transfected group (9.32±1.52 and 5.61±2.24,respectively) than those in vector-transfected (2.47 ± 0.23 and 0. 67 ± 0. 12, respectively) and nontransfected (1.21±0. 69 and 0. 86 ± 0.44, respectively) groups (P= 0.00). The average value of MVD and fluorescent express of vascular endothelial growth factor (VEGF) were lower in MMEtransfected group when compared with those in vector-transfected and non-transfected groups (P =0.00). The average tumor size in MME-transfected group was small in comparison with vectortransfected and non-transfected groups (P= 0.00). Conclusions MME is demonstrated to be one of matrix metalloproteinase that closely related with angiostatin production and has inhibitory effect on tumor growth in tumor-bearing mice.
8.The role of TrkA/TrkB in radiation-induced hippocampal neurogenesis impairment
Haohao WU ; Xin DING ; Meiling XU ; Peiwen DAI ; Junjun ZHANG ; Shengjun JI ; Ye TIAN
Chinese Journal of Radiological Medicine and Protection 2017;37(4):241-245
Objective To investigate the roles of TrkA and TrkB in radiation-induced hippocampal neurogenesis impairment.Methods Fifty-six rats were randomized into radiation group and sham control group.Radiation group received whole brain irradiation at a single dose of 10 Gy.The hippocampus were separated from rats in day 1,day 3,day 14 and 1 month after irradiation.Western blot and RT-PCR were applied to detect the protein levels and mRNA levels.Golgi staining was used to observe the dendritic spine of hippocampus.Immunofluorescence was performed to detect neural precursor's proliferation.Results Compared with control group,the numbers of dendritic spine significantly decreased after irradiation and its shape change obviously.Immunofluorescence showed a significant decrease in neural precursor's proliferation comparing with control group (t =6.49,P < 0.05).Protein level of TrkA expression increased (t =2.64,3.06,4.80,2.64,P < 0.05),while the levels of TrkB protein expression decreased significantly (t =4.59,3.06,2.81,2.57,P < 0.05).The mRNA level of TrkA expressions increased (t =4.57,3.06,5.39,5.86,P < 0.05),while the mRNA level of TrkB decreased (t =14.87,11.69,4.98,P < 0.05).Conclusions As a signaling pathways downstream of NGF and BDNF,TrkA and TrkB may play an important role in radiation-induced neurogenesis impairment.
9.Effect of phenolic ketones on ethanol fermentation and cellular lipid composition of Pichia stipitis.
Jinlong YANG ; Yichao CHENG ; Yuanyuan ZHU ; Junjun ZHU ; Tingting CHEN ; Yong XU ; Qiang YONG ; Shiyuan YU
Chinese Journal of Biotechnology 2016;32(2):185-194
Lignin degradation products are toxic to microorganisms, which is one of the bottlenecks for fuel ethanol production. We studied the effects of phenolic ketones (4-hydroxyacetophenone, 4-hydroxy-3-methoxy-acetophenone and 4-hydroxy-3,5-dimethoxy-acetophenone) derived from lignin degradation on ethanol fermentation of xylose and cellular lipid composition of Pichia stipitis NLP31. Ethanol and the cellular fatty acid of yeast were analyzed by high performance liquid chromatography (HPLC) and gas chromatography/mass spectrometry (GC/MS). Results indicate that phenolic ketones negatively affected ethanol fermentation of yeast and the lower molecular weight phenolic ketone compound was more toxic. When the concentration of 4-hydroxyacetophenone was 1.5 g/L, at fermentation of 24 h, the xylose utilization ratio, ethanol yield and ethanol concentration decreased by 42.47%, 5.30% and 9.76 g/L, respectively, compared to the control. When phenolic ketones were in the medium, the ratio of unsaturated fatty acids to saturated fatty acids (UFA/SFA) of yeast cells was improved. When 1.5 g/L of three aforementioned phenolic ketones was added to the fermentation medium, the UFA/SFA ratio of yeast cells increased to 3.03, 3.06 and 3.61, respectively, compared to 2.58 of the control, which increased cell membrane fluidity and instability. Therefore, phenolic ketones can reduce the yeast growth, increase the UFA/SFA ratio of yeast and lower ethanol productivity. Effectively reduce or remove the content of lignin degradation products is the key to improve lignocellulose biorefinery.
Acetophenones
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chemistry
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Ethanol
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chemistry
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Fermentation
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Industrial Microbiology
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Ketones
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chemistry
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Lignin
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chemistry
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Lipids
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chemistry
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Phenols
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chemistry
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Pichia
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chemistry
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Xylose
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chemistry
10.Metagenomics in studying gastrointestinal tract microorganism.
Bo XU ; Yunjuan YANG ; Junjun LI ; Xianghua TANG ; Yuelin MU ; Zunxi HUANG
Chinese Journal of Biotechnology 2013;29(12):1721-1735
Animal gastrointestinal tract contains a complex community of microbes, whose composition ultimately reflects the co-evolution of microorganisms with their animal host. The gut microbial community of humans and animals has received significant attention from researchers because of its association with health and disease. The application of metagenomics technology enables researchers to study not only the microbial composition but also the function of microbes in the gastrointestinal tract. In this paper, combined with our own findings, we summarized advances in studying gastrointestinal tract microorganism with metagenomics and the bioinformatics technology.
Animals
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Gastrointestinal Tract
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microbiology
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Humans
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Hyperglycemia
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etiology
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Inflammatory Bowel Diseases
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etiology
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Metagenome
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physiology
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Metagenomics
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methods
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Obesity
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etiology