1.Effects of ligustrazine on the calcineurin-? expression in lung tissue of rats under simulated weightlessness condition
Ye ZHANG ; Tianzhi LI ; Changting LIU
Medical Journal of Chinese People's Liberation Army 2001;0(12):-
Objective To study the dynamic changes in calcineurin-? expression in lung tissue of rats under simulated weightlessness condition,and the influence of ligustrazine(tetramethylpyrazine) on the changes in its expression.Methods The rat model of simulated weightlessness condition was reproduced by suspending the rat by tail in-30?.Thirty healthy Wistar rats were randomly divided into 3 groups(10 each): control group,suspended group(rat was suspended by tail for 7 days) and ligustrazine group(rat was suspended by tail and ligustrazine was given for 7days).In the ligustrazine group,the ligustrazine was gavaged in a dose of 1.5mg/kg(once a day).The expression of calcineurin-? in lung tissue was determined by immunohisochemistry and Western blotting.Results It was revealed by immunohisochemistry and Western blotting that the level of expression of calcineurin-? in lung tissue of the animals in suspended group was significantly higher that in control group and ligustrazine group(P0.05).Conclusion The level of expression of calcineurin-? in rat lung tissue may be increased obviously under the simulated microgravity condition,while ligustrazine treatment may down-regulate the calcineurin-? expression.
2.Clinical evaluation of mini/VITAL and Bact/Alert, two automated blood culture systems
Xiuzhen ZHANG ; Yunjian HU ; Tianzhi XUAN
Chinese Journal of Laboratory Medicine 2001;0(05):-
Objectives To evaluate mini/VITAL and BacT/Alert, two fully automated blood culture systems. Methods Standard mini/VITAL AER and ANA bottles (bioM′erieux, Marcy 1′Etoile, France) and BacT/Alert FAN aerobic and FAN anerobic bottles (organon Netherlands) were used. The bottles were analysed over a period of 7 days. A total of 600 samples of blood, 108 samples of body fluid, and 100 strains of imitation were detected by mini/VITAL and BacT/Alert parallelly. The bottles of flagged positive were smeared and Gram stained before being examined under a microscope. Subcultures were performed in parallel on fresh blood agar and chocolate agar incubated in microaerophilic Conditions with 5% CO 2. All the bottles flagged negative were examined in the same conditions as the positive bottles. Results mini/VITAL: The positive rate for aerobic and anaerobic blood cultures was 10% and 5% respectively, for aerobic body fluid culture was 26 9%. No contaminants were detected. 0.5% false positive and 0.8% false negative were detected. 90% of positive sample were detected in 48 h. The shortest time of report of positive bottles was 1.5 h for blood culture. BacT/Alert: The rate of positive of aerobic and anaerobic blood culture was 9.8% and 5% respectively. The positive rate of body fluid culturs was 26.9%. There were used 3 bottles contaminated. The false positive and false negative rate were 0.5% and 0 98% respective. 95.5% of positive bottles were detected in 48 h. The shortest time of flagged positive was 2.5 h. Conclusion mini/VITAL and BacT/Alert were accurate automated blood culture systems for the detection of bacteremia. There was no significant difference on the speed of detection between BacT/Alert FAN bottles and mini/VITAL standard bottles.
3.In vitro Antibacterial Activity of Home-made Rifamycin against Meticillin Resistant Staphylococcus and Other Pathogens of Clinical Isolates
Xiuzhen ZHANG ; Dongke CHEN ; Yunjian HU ; Tianzhi XUAN
Chinese Journal of Nosocomiology 2001;11(1):18-20
OBJECTIVE The in vitro activity of home-made rifamycin was investigated.METHODS Minimal inhibitory concentrations(MICs) were determined by agar dilution method using multipoint inoculator.RESULTS The results indicated that MIC50 and MIC90 of rifamycin against MRSA and MSSA were similar to vancomycin. The values were 1 and 2 mg/L, respectively. Rifamycin against MRSE was 4 times stronger than vancomycin.The value of MIC50 was 0.5 mg/L.The MIC50 of rifamycin against S.pneumoniae,Branhamella catarrhalis,and Listeria monocytogenes were 8,128 and 4 times lower than vancomycin, respectively.CONCLUSIONS There are good antibacterial activity of home-made rifamycin against meticillin resistant Staphyloccocus and the most species of clinical isolates,so can be used the infective diseases by MRSA and MRSE.
4.Mutant Prevention Concentration of Three Cephalosporins Against Staphylococcus aureus and Streptococcus pneumoniae
Hongtao XU ; Fengrong TAO ; Peng ZHANG ; Dongke CHEN ; Tianzhi XUAN ; Xiaoman AI ; Yunjian HU ; Xiuzhen ZHANG
Chinese Journal of Nosocomiology 2006;0(12):-
OBJECTIVE To determine the mutant prevention concentration(MPC) of 3 cephalosporins against clinical isolates of Staphylococcus aureus and Streptococcus pneumoniae.METHODS Agar dilution was used to determine the minimum inhibitory concentration(MICs) and MPCs of cefaclor,cefprozil and cefuroxime against S.aureus and the MICs to Str.pneumoniae.The MPCs against Str.pneumoniae were determined by mixing-bacterium.RESULTS The MPCs and the ratio of MPC90/MIC90 of cefaclor,cefprozil and cefuroxime against S.aureus were 32,16;16,16;2,8;and the MPCs and the ratio of MPC90/MIC90 against Str.pneumoniae were 8,16;4,32;2,8,respectively.CONCLUSIONS The ability of cefuroxime for restricting the selection of resistant mutant of Str.aureus and S.pneumoniae is stronger than cefaclor and cefprozil.
5.Research on prediction model of learning behavior of clinical medical postgraduates-comparative analysis of linear regression and machine learning
Chi ZHANG ; Yanqing LI ; Deping LIU ; Peizhong WANG ; Tianzhi CHEN ; Wenzhuo LI ; Jinzhong JIA
Chinese Journal of Medical Education Research 2021;20(3):350-355
Objective:To compare the prediction efficiency of traditional linear regression model and four machine learning models on the learning behavior of clinical medical postgraduates, and to explore the pros and cons and applicability of different prediction models.Methods:A total of 6,922 clinical medical postgraduates were surveyed, their comprehensive learning behavior scores were obtained through the learning behavior scale. In the training set, Lasso linear regression and artificial neural network, decision tree, Bootstrap random forest, and lifting tree were used to build prediction models respectively. The above models were used to predict the validation set data and compare the prediction efficiency.Results:The comprehensive learning behavior score of clinical medical postgraduates was (3.31±0.54) points, and the overall compliance rate was 74.02%. In the linear regression model, the influence of age, school level, degree type, learning interest, pressure and satisfaction on learning behavior were statistically significant. In the prediction of validation set, the sensitivity, specificity, and accuracy of the linear regression model were 0.484, 0.914, and 0.801, respectively. The indexes of the four machine learning models were higher than those of the traditional linear regression model, and the Bootstrap random forest had the highest elevation.Conclusion:The linear regression model has a good prediction effect on learning behavior, and machine learning is superior to linear regression model in terms of accuracy of prediction. However, traditional linear regression models are superior to machine learning models in computational efficiency and interpretability.
6.Influence of sulbactam content on susceptibility testing results of cefoperazone/sulbactam combination disks
Jihong HU ; Nan ZHANG ; Zhenxiang GAO ; Yi GAO ; Ran ZHANG ; Xiaoman AI ; Hongtao XU ; Fengrong TAO ; Tianzhi XUAN ; Yunjian HU
Chinese Journal of Laboratory Medicine 2010;33(3):231-235
Objective To study the discrepancy influence of the sulbactam content on susceptibility testing results of cefoperazone/sulbactam combination disks.Methods Agar dilution method was used to determine MICs of cefoperazone,cefoperazone/sulbactam(2:1 and 1:1),and disk diffusion was used to detect the zone diameters of cefoperazone,cefoperazone/sulbactam(75/30 and 75/75μg/disk)disks against 534 clinical gram-negative isolates.The discrepancy within the results of MICs,zore diameters,the method of agar dilution and disk diffusion was analyzed.Results By standard agar dilution method,MIC_(50) of cefoperazone,cefoperazone/sulbactam(2:1 and 1:1)were 32,16,16μg/ml,and MIC_(90) of those were ≥256.128,64 μg/ml respectively.No statistic discrepancy was found for MICs between the ratios of 2:1 and 1:1 combination by Wilcoxon ranks test(Z=-0.248,P=0.804).Susceptibility rate,resistance rate,and intermediate rate with 75/30μg disk were 55.3%,24.5%and 20.2%respectively,which were similar to those determined by agar dilution method.Susceptibility rate,resistance rate,and intermediate rate(I%)with 75/75μg disk were 72.5%,12.4% and 15.1% respectively,compared with the susceptibility rate from 75/30μg disk was 17.2% higher.Statistic discrepancy were tested by paired t-test (t=21.613,P<0.01)with two groups of whole strains' zone diameters from 75/30μg and 75/75μg disks,and resulting in the difference of susceptibility or resistance rates for ESBL-producing strains,Acinetobacter bauamnnii and Enterobacteriaceae without ESBL tested isolates.On the contrary,for Pseudomonas aeruginosa,Stenotrophomonas maltophilia and ESBL negative isolates,the zone diameters discrepancy was not statistically significant between the results from 75/30μg and 75/75μg disks.Conclusions There is no statistic discrepancy between the susceptibility results from cefoperazone/sulbactam(2:1 or 1:1 ratios)in dilution method and in diffusion method with 75/30μg disk.When the 75/75μg disk is used to be tested for ESBL-producing strains,Acinetobacter bauamnnii and other Enterobacteriaceae,the results should be shown with sulbactam content.
7.Efficacy of enternal nutrition support with high-energy density nutrition emulsion in severely burned patients
Tianzhi HAO ; Jingmin ZHU ; Wenbo HU ; Hua ZHANG ; Zhenhui GAO ; Xuehui WEN ; Jingjie LIU ; Zhi ZHOU ; Gang LU
Chinese Journal of Clinical Nutrition 2009;17(1):10-12
Objective To study the mechanism of glutamine dipeptide on wound healing after operations on bums. Methods Totally, 30 burned patients were randomly divided into study group and control group (15 cases in each group). All patients received parental nutrition support after operation. Study group patients were supplemented with glutamine dipeptide at a dose of 0. 5 g · kg±1 · d±1. The plasma free hydroxyproline level was measured by a standard amino acid analyzer 1 day before operation and 7 days after operation and the wound healing time was recor± ded. Results The plasma free hydroxyproline levels of both groups were higher than the normal values before opera± tion but without significant difference [control group: (2. 24 ±0. 84) fig/ml, study group: (2. 32 ±0.92) μg/ml, normal value: (1.27 ±0.44) μg/ml]. On the post±operative 7 day, the plasma free hydroxyproline level of study group [ (4. 31 ±1. 05) μg/ml] was significantly higher than that of control group [ (3. 04± 1. 01) μ/ml] (P = 0.002). The wound healing time of study group [ (29. 7±5.3) d] was shorter than that of control group but with± out significant difference [ (33. 3 ±7.5) d, P = 0. 14 ]. Conclusion The intravenous supplementation of glutamine dipeptide may increase the plasma hydroxyproline level after operation and thus promote wound healing.
8.Therapy for Graves' ophthalmopathy.
Jianguo ZHENG ; Xia ZHANG ; Rixiang GONG ; Ji WANG ; Tianzhi TAN
Journal of Biomedical Engineering 2004;21(5):876-879
Graves' ophthalmopathy (GO) is also called thyroid-related eye disease, infiltrative ophthalmopathy, which is related with the autoimmunity of thyroid, especially hyperthyroidism. Its morbidity ragnes from five percent to ten percent of hyperthyroidism, and the morbidity of male patients is higher than that of the female patients. The treatment of severe GO is a difficult task for doctors. The therapeutic effect is not always satisfactory. In order to solve this knotty problem, researchers have been devoting themselves to the development of new therapeutic methods. Here, the development of the therapies for GO is introduced, and the trends of treatments are prospected.
Combined Modality Therapy
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Exophthalmos
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etiology
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radiotherapy
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therapy
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Graves Disease
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complications
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radiotherapy
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therapy
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Humans
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Immunoglobulins
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therapeutic use
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Prednisolone
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therapeutic use
9.A comparison on radiochemical behavior and biological property of antisense oligonucleotide labeled with technetium-99m by two methods: NHS-MAG3 versus SHNHP.
Yunchun LI ; Tianzhi TAN ; Jianguo ZHENG ; Chun ZHANG
Journal of Biomedical Engineering 2008;25(4):889-902
This study was undertaken to explore and compare the radiochemical behavior and biological property of antisense oligonucleotide (ASON) labeled with Technetium-99m using two methods: N-hydroxysuccinimidyl S-acetylmercaptoacetyltriglycline (NHS-MAG3) versus hydrazino nicotinamide derivative (SHNH). After SHNH and NHS-MAG3 were synthesized, ASON was labeled with Technetium-99m using SHNH and NHS-MAG3 as a bifunctional chelator, separately. The stability in vivo and in vitro, the combination with plasma albumen of rabbit, the biodistribution in BALB/ C mice and the HT29 cellular uptake were compared between labeled compound 99mTc-SHNH-ASON, using SHNH as a bifunctional complex reagent, and 99mTc-MAG3-ASON, using NHS-MAG3 as a bifunctional chelator. The results revealed that the labeling rate and the stability of 99mTc-MAG3-ASON were evidently higher than that of 99mTc-SHNH-ASON (P < 0.05), the combination rate of 99mTc-MAG3-ASON with plasma albumen was markedly lower than that of 99mTc-SHNH-ASON (P < 0.05); the biodistribution of 99mTc-MAG3-ASON was markedly lower than that of 99mTc-SHNH-ASON in blood, heart, stomach and intestines (P < 0.05), slightly lower than that of 99mTc-SHNH-ASON in liver and spleen (P > 0.05), and markedly higher than that of 99mTc-SHNH-ASON in kidney (P < 0.05); the HT29 cellular uptake rates of 99mTc-MAG3-ASON was markedly higher than that of 99mTc-SHNH-ASON (P < 0.05). Therefore, the radiochemical behavior and biological property of 99mTc-MAG3-ASON labeled using NHS-MAG3 is better than that of 99mTc-SHNH-ASON labeled using SHNH.
Animals
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Colonic Neoplasms
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metabolism
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pathology
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Glycine
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analogs & derivatives
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chemistry
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pharmacokinetics
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Humans
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Isotope Labeling
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methods
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Mice
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Mice, Inbred BALB C
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Niacinamide
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analogs & derivatives
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chemistry
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pharmacokinetics
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Oligonucleotides, Antisense
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chemistry
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pharmacokinetics
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Radiopharmaceuticals
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chemical synthesis
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pharmacokinetics
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Succinimides
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chemistry
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pharmacokinetics
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Technetium Tc 99m Mertiatide
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chemistry
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pharmacokinetics
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Tumor Cells, Cultured
10.Preparation of liposome-mediated 99m-technetium-labeled antisense oligonucleotides of c-myc mRNA.
Jianguo ZHENG ; Tianzhi TAN ; Chun ZHANG ; Yunchun LI ; Zhenglu LIANG ; Juguang TU
Journal of Biomedical Engineering 2003;20(4):704-707
To explore the preparation method of liposome-mediated 99m-technetium-labeled antisense oligonucleotides of c-myc mRNA and lay foundations for antisense imaging and treatment, antisense oligonucleotides (DNA) with 15 bases and di-functional chelate, hydrazino nicotinamide derivatives, were synthesized. After DNA combined with chelate, they were labeled with 99m-technetium to form compounds, 99mTc-chelate-DNA (99mTc-DNA), and were purified through Sep-Pak reverse column(C18, Waters) by using methanol and water as eluent. The leaching curve was made; the labeling efficiency was calculated. The products were then encapsulated with cation liposome to form liposome-mediated 99mTc-DNA. The radiochemical purity and stability of the liposome-mediated 99mTc-DNA were tested through strip chromatography. The labeling efficiency was 63.37% +/- 3.51% at the radioactive concentration of 1480 MBq, 62.52% +/- 3.69% at that of 740 MBq, 59.82% +/- 5.12% at that of 592 MBq. There were no significant differences between these labeling efficiencies. The radiochemical purity was 96.47% +/- 3.01%. The liposome-mediated radiolabeled antisense oligonucleotides were stable after incubation with water or serum. Therefore liposome-mediated radiolabeled antisense oligonucleotides could be obtained through hydrazino nicotinamide derivatives as di-functional chelate and liposome as vector.
DNA, Antisense
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chemical synthesis
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Drug Compounding
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methods
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Drug Stability
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Isotope Labeling
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methods
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Liposomes
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Proto-Oncogene Proteins c-myc
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genetics
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RNA, Messenger
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genetics
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Technetium