AIM: To prepare a novel long-circulating paclitaxel-containing liposomes, evaluate its quality and study its toxicity to gastric cancer cell line BGC823. METHODS: From May to November in 2006, the experiment was carried out in the Laboratory of Chemistry, Kaili College and the Laboratory of Physics and Chemistry Department, Southeast Guizhou Center for Disease Control and Prevention.①The novel long-circulating paclitaxel-containing liposomes was prepared by ultrasonic film method. Encapsulation efficiency and stability of the paclitaxel liposomes were measured by RP-HPLC.②The paclitaxel liposomes were dispersed in phosphate buffer at the pH value of 6.5, at 4 ℃ for 30 days, and the change of drug loads was observed.③The proliferation of BGC823 cell at logarithmic phase was tested by MTT method under the paclitaxel liposomes concentrations of 5, 10, 15, 20 mg/L. Meanwhile the paclitaxel free drug was taken as controls. RESULTS: ①Encapsulation efficiency of this paclitaxel liposomes was high to 97.6% detected by RP-HPLC.②When the paclitaxel liposomes were stored in refrigerator of 4 ℃, there was no flocculent precipitation during one month. Drug loaded in liposome after 3, 8, 15, 22, 30 days of preservation was respectively 97.3%, 96.2%, 95.6%, 94.9%, and 94.2%. The drug leakage of the paclitaxel liposomes was only 6% one month after dispersing in this buffer.③The result of in vitro cell toxicity showed that, under the drug concentration of 5, 10, 15, 20 mg/L, the inhibition rate to BGC823 cell of paclitaxel liposomes was 33.46%, 44.15%, 51.94%, 68.64% respectively, where those of free paclitaxel was 35.24%, 48.37%, 57.49%, 74.84%. CONCLUSION: ①This high-encapsulated and stable long-circulating paclitaxel-containing liposomes is expected to provide a more effective paclitaxel preparation.②The inhibition rate to BGC823 cell of the paclitaxel liposomes is low to that of free paclitaxel at the same drug concentration, indicating that it can present the slow release of liposomes.

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.

Objective To study the effects of simulated gravity loss on nuclear factor Kappa-B expression in rats′ pulmonary tissue, and to investigate the mechanism of changes in NF-?B during simulated loss of gravity. Methods Tail-suspension(TS) was used as the method to simulate the physiological effects of weightlessness. 40 Wistar male rats Wistar rats were randomly divided into 4 groups: control for 7 days (7d CON), 21d CON, TS for 7d (TS7d) and TS21d. The dynamic express of nuclear factor Kappa-B in lung tissue was respectively assessed using the immunohisochemical technique. Results Compared with control group, the expression level of NF-?B in the lung tissue of tail-suspension 7d rats was elevated significantly (P

Objective: To provide references for the locating the third ventriculos tomy by measuring normal brain MRI data. Methods: Three hundreds normal brain MRI data were tagged and measured. The relevant reference data about third ventricle fistulization were obtained after statistics processing. Rosults: There were no statistical differences in the ratio of the distance before and after into the skull (BC / AC) in all age groups (P＞0.05). There were statistical differences in parameters of surgical approach-the distance of the middle line beside the incision (L),the depth inside the scalp (H) and the angle between the long axle of endoscope and the center sagittal plane (a) between ≤ 9-year--old and other age groups. The 95 percent confidence interval about parameters of surgical approach was obtained among all age groups. Conclusion: The results provide the reference of surgical treatment for the individual, enjoying the advantage of accuracy location and wide application.

OBJECTIVE To compare commonly used antibiotics including cefotaxime,ceftazidime imipenem and meropenem inductivity to L1,L2 ?-lactamases from Stenotrophomonas maltophilia.METHODS RT-PCR method was used to determine the expression of L1,L2 ?-lactamases under the condition of different concentrations(1/4,1,4?MIC)of antimicrobial agents.Electrophoresis strip of L1,L2 ?-lactamases was quantified by software Image J.Minimal inhibitory concentrations(MICs)were detected by agar dilution method when different concentrations of antibiotics were as inductors.RESULTS Different concentrations of four antibiotics being used as inductors,electrophoresis strips of L1,L2 amplicons were not found in strains of blank control and those whose media had imipenem,meropenem or cefotaxime(4?MIC).The weaker electrophoresis strips were found in the isolates whose media had ceftazidime(1/4,1,4?MIC)or cefotaxime(1/4?MIC),but the strongest electrophoresis strips,the most quantities of expression and higher MICs were shown in the isolates whose media had cefotaxime(1?MIC)(P

Objective To explore the impact of different doses of butylphthalide on renal interstitial fibrosis in mice with obstructive nephropathy, and to discuss the correlation between Nrf-2 expression level and renal interstitial fibrosis. Methods Totally 72 male CD-1 mice of clean grade were selected and randomly assigned into 4 groups:sham operation group (Sham), model group (UUO), low dose of butylphthalide group (NBPL) and high dose of butylphthalide group (NBPH). In addition to the control group, UUO model was established in other three groups. NBPL group was given NBP 150 mg/(kg· d) by gavage since postoperative day 1,NBPH group was given NBP 220 mg/(kg·d) by gavage. Sham group and UUO group were given equal volume of saline by gavage. Six mice were sacrificed at the third, 7th, 14th day, respectively. The obstructive renal tissue was selected for immunohistochemical staining and Western blot assay. The expression levels of Nrf- 2 and type Ⅰ collagen were detected by Western blot assay. Results The IOD value of type Ⅰ collagen was increased with time in UUO group, and which showed a gradual decreasing trend in Sham group, NBPL group and NBPH group (P<0.05). The IOD values at different time points were significantly higher in UUO group, NBPL group and NBPH group compared to those of Sham group. The IOD values were significantly decreased in NBPL and NBPH groups than that of UUO group, and IOD value was lower in NBPH group than that of NBPL group (P<0.05). Western blot assay showed that IOD values of Nrf-2 and type Ⅰ collagen at 7 d and 14 d were increased in UUO group, NBPL group and NBPH group compared with those of Sham group. The IOD values of Nrf-2 protein were increased, and IOD values of type Ⅰcollagen were decreased, in NBPL group and NBPH group than those of UUO group. The IOD value of Nrf-2 protein was decreased in NBPL group than that of NBPH group, but the IOD value of type Ⅰcollagen was increased in NBPL group than that of NBPH group (P<0.05). Conclusion NBP can improve renal interstitial fibrosis in UUO mice, which may be related with the increased expression of Nrf-2 and the down-regulated expression of type I collagen.

OBJECTIVE To investigate the distribution and characterization of the classes Ⅰ,Ⅱ and Ⅲ integrons on Stenotrophomonas maltophilia and clarify their influence on the bacterial drug-resistance.METHODS A multi-PCR assay using specific primers of int1,int2 and int3 was constructed to screen classes Ⅰ,Ⅱ and Ⅲ integrons.RESULTS Class Ⅰ integron was detected in 13.4% of clinical isolates,3 isolates harbored among class Ⅱ integrons. There was not been reported in abroad.CONCLUSIONS Classes Ⅰ and Ⅱ integrons could play an important role in causing the antibiotic multidrug resistance.

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.

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.

Objective To explore the repair of the open compound wounds in lower extremities caused by multiple factors. Methotis Transplantation of cutaneous.musculo-cutaneous or greater omentum flaps were applied to 155 patients of open compound lower extremity wounds. Results The wound healing rate following first operation was 50% and that following two operations was 14.8%.While the wounds were healed in 7.7% of patients after three operations. Conclusion Transplantations of cutaneous,musculo-cutaneous or greater omentum flaps ale effective to repair and reconstruct the open compound lower extremity wounds.