[Objective]In order to dynamically observe the ossification process by living small animal Micro-CT in a rat femur distraction osteogenesis (DO) model,the author applied a special designed external fixiator system. [Methods]A femur DO model was made on 12 SD rats.After 7 days of latency,the femurs were distracted at a speed of 0.25 mm every 12 hours for 14 days.At the first day of consolidation period,the steel external fixiators were substituted by radio-transparent polymer splint material made fixiators.At 7 and 21 days of consolidation period,two randomly selected rats were sacrificed for histological examination.The other 8 rats were selected for X-ray and living Micro-CT examination at 0,7,21,35 days of consolidation period.All animals were sacrificed at 35 days of consolidation period,5 for biomechanical test,3 for histological examination.[Results]There was no significant new bone formed in distracted zone at latency and distraction periods.The volume of distracted zone increased little in the following 5 weeks of consolidation period.Bone volume,bone mineral content,bone volume fraction,and the number of trabeculae all increased over the consolidation period,while mineral content of mineralized tissue and thickness of traleculae did not increased until 3 weeks after consolidation began.At final observation (56 days post operation),there still exist un-mineralized cartilage tissues in the central of distracted zone,and the distracted femurs had lower biomechanical property when compared with corresponding normal femurs.[Conclusion]1) Radio-transparent polymer splint is a satisfactory substitute of steel external fixator.2) Micro-CT is a useful tool for dynamical observing and evaluating bone formation status in DO model.3) The increasing of bone volume began at the end of distraction,lasting at least 5 weeks,while the remodeling of new formed bone began 3 weeks after distraction ended.The increasing and remodeling of new formed bone was not concord.This result indicates that,in order to obtain proper results,the corresponding interference should be taken at different time points.

Objective:To compare and analyze the value of diffusion weighted imaging (DWI) and apparent diffusion coefficient (ADC) of 1.5T magnetic resonance (MR) in differential diagnosis for localized prostate cancer, chronic inflammatory response and benign hyperplasia.Methods: 80 patients with localized prostate cancer were enrolled in the research. The signal to noise ratio (SNR) of DWI, ADC value and semi-quantitative classification of DWI on lesions were measured, and the diagnostic efficiencies of them were compared by using ROC curve.Results: In the 80 patients with localized prostate cancer patients, there were 52 malignant lesions and 43 benign lesions in peripheral band, and there were 31 malignant lesions and 46 benign lesions in central gland. The ADC values of prostate cancer in peripheral band and central gland were 0.91±0.12 and 0.86±0.15, respectively, and they were significantly lower than that of normal tissue (1.68±0.23 and 1.28±0.31) and benign lesions (1.24±0.21 and 1.12±0.16). The semi-quantitative classifications of DWI for benign lesions were significantly higher than that for malignant lesions in peripheral band and central gland, respectively (x2=20.88,x2=12.14;P<0.05). For the diagnostic efficiency of ADC, the sensitivities of benign and malignant lesions in peripheral band and malignant gland were 91.3% and 79.1%, respectively, and the specificities of them were 89.6% and 70.2%. And they was significant higher than the corresponding sensitivities (71.2% and 51.3%)and specificities (78.4% and 65.8%) of DWI imaging.Conclusion: Both of DWI and ADC of 1.5T magnetic resonance are the important indexes in differential diagnosis for prostate cancer, chronic inflammatory response and benign hyperplasia, while ADC value is better than DWI image in the clinical efficiency.

Humans ; Radiation Injuries ; drug therapy ; prevention & control ; Radiation, Nonionizing ; Radiation-Protective Agents ; therapeutic use ; Radioactive Hazard Release ; prevention & control

Child ; Encephalitis, Viral ; pathology ; Enterovirus A, Human ; Enterovirus Infections ; complications ; Heart Failure ; etiology ; Humans ; Respiratory Insufficiency ; etiology

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OBJECTIVE:To prepare and characterize celecoxib-loaded PLGA nanoparticles. METHODS:Emulsification-solvent evaporation method was adopted to prepare celecoxib-loaded PLGA nanoparticles. With encapsulation efficiency and particle size as the indexes,Plackett-Burman design was preferred to screen the formulation and variables which had a significant effect on the property of nanoparticles. And then Box-Behnken response surface method was used to further optimize selected variables including mass concentration of PLGA,ultrasonic power and ultrasonic time,followed by verification. Malvern particle size analyzer was used to determine the particle size distribution of nanoparticles and Zeta potential of nanoparticle by the optimal formulation technol-ogy,and transmission electron microscope was used to observe the morphology of the nanoparticles,and their drug release in vitro behavior and stability(25,5 ℃)were also observed. RESULTS:The optimal formulation and technology was as follows as PLGA mass concentration of 30.0%,ultrasonic power of 180 W and ultrasonic time of 8 min. For the prepared nanoparticles,encapsula-tion efficiency and particle size were (85.7 ± 4.1)% and (226.1 ± 36.1) nm (n=3) respectively;particle size distribution was (176.2±41.2)nm,polydispersity index was 0.211±0.021,and Zeta potential was(-37.3±1.6)mV. Under the electron micro-scope,the nanoparticles were homogeneous in particle size and distributed spheroidally,with 24 h accumulative release of 52.4%. They were stable within 3 months at 5℃. CONCLUSIONS:Celecoxib-loaded PLGA nanoparticles have been prepared successfully.

Objective To investigate the effect of comprehensive intervention therapy of losing weight on leptin and blood lipid,blood glucose,insulin in adolescent girl students with simple obesity.Methods Simple obesity adolescent girl students were accepted the losing weight therapy composed of the aerobic exercise,reasonable diet,behavior modification and medical supervision for 10 months.Then the changes of blood leptin and correlated hormone were examined before test,during test and after test,respectively.Results The leptin and correlated hormone levels were significantly higher in obesity subjects than that in normal subjects,and the levels of serum leptin was positively correlated with BMI and insulin.The blood leptin and blood lipid,blood glucose,insulin were decreased obviously after experimental losing weight.Conclusion Comprehensive intervention therapy of losing weight can significantly lose weight,leptin and insulin,so it plays an important role in modifying the metabolism disorder

An inner-bioreactor rapid filtration sampling probe was designed to resolve the problems of continuous sampling the fermentation broth in on-line measurement the fermentation process. The probe consists of a support, a plug valve, an O-ring, a filter membrane and a pipe cover. It can be inserted directly into the bio-reactor withstanding high-temperature sterilization before fermentation, or preventing the bacteria's invasion during sampling. Fermentation broth in tank is cross-flow filtrated by a cylindrical ceramic membrane which is used as filtration membrane, and then the sterile permeated liquid is transported to the analyzer by a peristaltic pump. The sampling experiments using this device was described for sampling glucose solution indicating it is suitable for fermentation online sampling. The sampling rate is up to 3. 0 mL/ min, glucose permeability maintains 100% , and the delay time caused by the probe is about 2 min.

Objective:To prepare celecoxib nanosuspension ( CXB-NSs) and study the pharmacokinetics of CXB-NSs in rats. Methods:CXB-NSs were prepared by an anti-solvent precipitation and high pressure homogenization method. The particle size, polydispersion index ( PdI) and zeta potential of the nanosuspension were studied. Totally 12 Wistar rats were randomly divided into CXB-NSs group and CXB suspension group, and gastric drug dose was 100 mg·kg-1 . CXB concentration in plasma was determined by HPLC and the pharmacokinetic parameters were calculated by 3P97 software. Results: The particle size, polydispersion index, zeta potential of CXB-NSs was (442. 5 ± 61. 9) nm, 0. 312 ± 0. 057 and ( -31. 6 ± 3. 9) mV, respectively. AUC (0-t) of CXB suspension and CXB-NSs was (5.13 ±0.77) and (13.51 ±3.18) mg·L-1·h, half time (t1/2) was (12.31 ±1.91) and (12.73 ±1.83) h, Tmax was (2. 48 ± 0. 37) and (1. 41 ± 0. 27) h and Cmax was (0. 94 ± 0. 31) and (2. 38 ± 0. 25) mg·L-1 , respectively. Conclusion:CXB-NSs can remarkably increase bioavailability in rats.