Animals ; Bone Marrow ; metabolism ; Cell Division ; physiology ; Hematologic Diseases ; therapy ; Hematopoiesis ; physiology ; Hematopoietic Stem Cells ; cytology ; Humans ; Renin-Angiotensin System ; physiology

Objective To investigate celecoxib self-microemulsifying drug delivery system (CXB-SMEDDS) that was developed to increase the dissolution rate and oral bioavailability of celecoxib.Methods The formulation of CXB-SMEDDS was optimized by pseudo-ternary phase diagrams analysis.The appearance, morphology, particle size distribution and in vitro drug release behavior of CXB-SMEDDS were investigated after diluted by water.The bioavailability of CXB-SMEDDS was determined by oral administration to rats compared with CXB suspension.Results An optimized formulation was selected: Medium chain triglycerides as oil phase, Tween 20 as surfactant, Transcutol HP as cosurfactant.The ratio of oil phase, surfactant and cosurfactant was 2∶9∶9.Upon mixing with water, CXB-SMEDDS formed a clear and transparent microemulsion solution with homogeneous small spherical under transmission electron microscopy.For particle size of CXB-SMEDDS was found to be (57.6±14.2) nm.The in vitro dissolution test indicated a significant improvement in release characteristics of CXB.The AUC of CXB-SMEDDS and CXB suspension were (5.54±0.94) and (3.32±0.59) mg·L-1·h, respectively.The relative bioavailability was 166.9%.Conclusion The SMEDDS can significantly increase celecoxib dissolution in vitro and bioavailability in vivo.

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 prepare celecoxib nanostructured lipid carriers and investigate the characteristics of tissue distribution in rats. Methods:Celecoxib nanostructured lipid carriers were prepared by a melt-emulsion ultrasonication and low temperature-solidifi-cation method. The physicochemical properties of nanostructured lipid carriers were studied, such as particle size distribution, zeta po-tential and morphology. The concentration of celecoxib in different tissues was determined after tail vein injection of celecoxib nano-structured lipid carriers in rats. Results:The obtained celecoxib nanostructured lipid carriers were spherical with the average particle size of (103. 5 ± 32. 6) nm and zeta potential of ( -37. 3 ± 5. 1) mV. The re of celecoxib nanostructured lipid carriers in liver, spleen, brain and muscle respectively was 3. 43, 2. 99, 2. 38 and 2. 93 times higher than that of celecoxib injection. Conclusion:The biodistribution of celecoxib is changed by the nanostructured lipid carriers. Celecoxib nanostructured lipid carriers have the characteris-tics of liver, spleen and muscle targeting, which is benefit to improving the efficacy.

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.

OBJECTIVEThis study aims to examine the prevalence and diameter of the bony canal structure of the posterior superior alveolar artery (PSAA), residual alveolar bone height, and distance of its inferior border from the alveolar crest using cone-beam computed tomography (CBCT).

METHODSCBCT images of maxilla in 116 patients were randomly selected from patients who underwent maxillary sinus augmentation procedure and/or posterior teeth implant therapy from April 2011 to September 2012. The lower border of the bony canal to the alveolar crest, diameter of the bony canal, and residual alveolar bone height below the sinus floor to the ridge crest were measured from CBCT scans. Data were presented using descriptive statistics.

RESULTSThe prevalence of the bony canal was 75.14% (133/177). The mean diameter of the bony canal was (0.96 ± 0.29) mm. The residual alveolar bone height was (7.14 ± 3.64) mm. The distance of the bony canal's inferior border from the alveolar crest was (17.92 ± 5.68) mm. No statistically significant differences between the right and left sides were observed (F = 0.295, P > 0.05). The mean diameter of the bony canal was significantly smaller in females than that in males (F = 0.187, P < 0.05). The maxillary alveolar dimension was significantly correlated with the residual alveolar bone height.

CONCLUSIONThe results from this study suggest that CBCT is a valuable tool in evaluating the presence of the bony canal of the PSAAs efore maxillary sinus surgery.

Objective To evaluate the efficacy of discriminant function analysis for pericolic infiltration in colorectal cancer on enhanced 64-slice spiral CT and to improve the diagnostic accuracy and specificity of pericolic infiltration. Methods Dynamic enhanced 64-slice spiral CT was performed in 49 colorectal cancer patients (49 masses in total) before surgery. One or two slices were selected for each mass, with a total of 96 slices. The 96 slices were classified into two groups (pericolic infiltration or nonpericolic infiltration group) according to pathological data. Discriminant analysis was performed on the CT values between the mass and the corresponding pericolic tissue 5 mm from the mass at different time points as follows; 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, and 75 s. The discriminant function was calculated, and the pericolic infiltration determined by discriminant function and CT morphology were compared with the pathological results. The CT values in pericolic and non-pericolic infiltration groups at different enhancement time points were assessed using analysis of variance. Results The mean CT values ranged from (43. 6 ±7. 8) HU to (52. 3 ±0. 8) HU in the pericolic infiltration group, and ranged from (100.4±20.3)HU to(116.2±21.4)HU in the non.perieolic infiltration group.At 20 s and 40 s,the mean CT vshle8 were(43.6±27.8)HU and(50.9±27.8)HU in the perleolic infiltration group, (102.0±16.9)HU and(116.2 ±21.4)HU in the non-perieolic infiltration group,respectively.The mean CT value in the pericolic infiltration group was significantly lower than that in the non-pericolic infiltration group at all contrast enhancement time points(F=6.278,P<0.01).A diseriminant function Was obtained as follows:D=-3.450+0.023Xl±0.017X2-0.00lX12-0.001X22+0.002X1×X2. Based on the CT morphology of colorectal cancer,69 slices were identified correctly and 27 slices were fulsely interpreted.the sensitivity.speeificity and accuracy for perieolic infiltration determination were 82.5%,64.3%and 71.9%.respectively.Based on diseriminant function,85 slices were identified correctly and 11 slices were falsely interpreted.the sensitivity,specificity and accuracy were 85.0%.91.1%and 88.5%,respectively.Conclusion The discriminant function with dynamic enhanced 64-slice spiral CT can improve the diagnostic accuracy and specificity of perieolic infiltration in eolorectal cancer patients.

Objective To explore the safety and effectiveness of percutaneous vertebrophasty(PVP)in the treatment of the metastatic tumor involved axis.Methods Ten patients(8 male,2 female)with osteolytic metastases involved axis were treated with PVPs.The anterolateral approach with fluoroscopy guidance was selected in 9 cases,while the posterolateral approach with CT guidance was selected in 1 case.Results Successful unilateral-paracentesis for PVP were achieved in all patients without intervention related complications such as bleeding and symptomatic polymethylmethacrylate(PMMA)leakage.CT scan taken following PVP showed that over 70% of the osteolytic metastatic area was well filled with PMMA in all cases.Varying degrees of pain relief were observed(CR in 7 cases,PR in 3 cases)within 7 days.All patients could support their heads without brackets.During a 3 to 24 months follow up after the procedures,No aggravated pain was found in the group.Two patients died in 4 months,3 Patients died in 8 to 11 months 4 patients died in 13 to 15 months,and 1 patient still was alive after 24 months.Conclusion Anterolateral or posterolateral approach to Aixs in PVP is safe and effective in treating osteolytic metastatic tumors.

Objective To investigate the features of intravertebral vacuum phenomenon (IVP)in vertebral compression fractures (VCFs). Methods Two hundred and nine patients with VCFs underwent percutaneous vertebroplasty (PVP) and percutaneous kyphoplasty (PKP). The biopsies and the images of X-ray, CT, MRI of VCFs were obtained. The consistency between IVP and osteonecrosis on histology and the positive predictive value (PPV), negative predictive value (NPV), sensitivity, specificity and Youden index of IVP for diagnosing local osteonecrosis in VCFs were analyzed. Fisher exact probability test was used to analyze the coherence between IVP and osteonecrosis. Results Histological examination revealed 146(69.9%) osteoporoses, 10 (4.8%) osteonecroses with osteoporoses, 53 (25.4%) neoplasms. Prior to surgery,10 cases of IVP were found. Plain radiograph showed horizontally oriented lucent cleft in the vertebral body;CT further confirmed the location of gas;T_1-weighted MR image appeared hypointensity,while the signal intensity of T_2-weighted MR image differed, depending on the duration of recumbency. Nine of 10 patients with IVP showed osteonecrosis on histology, while 9 of 10 patients with osteonecrosis contained IVP. The association of osteonecrosis on histology and the IVP was statistically significant(P <0.01). The PPV, NPV, sensitivity, specificity, and Youden index for diagnosing local osteonecrosis was 90% (9/10), 99.5% (198/199), 90.0% (9/10), 99.5% (198/199), and 0.9, respectively. Conclusion The IVP is stongly suggestive of local osteonecrosis in vertebral compression fracture.

Objective To investigate the usefulness of 99Tcm-MDP whole body bone scan in bone malignant fibrous histiocytoma (BMFH).Methods Fifteen patients (11 males,4 females,age ranged from 23 to 60 years,average age (50.4±12.8) years) who had documented BMFH and underwent 99Tcm-MDP whole body bone scan were retrospectively analyzed.The appearance of increased uptake,decreased uptake or defect in radioactivity on bone was considered as positive.The typical scintigraphic manifestations of BMFH were summarized and compared to other radiological imaging data.Results All 15 patients showed positive results.The lesions involved femoral in 10 cases(66.7％),46.7％(7/15) of which was distal femur.The lesions also involved sacrum,tibia,humerus,radius each in 1 case and multiple lesions in 1 case.Among 27 lesions found,63.0％ (17/27) showed strong increased radioactivity together with reduced or defect area and 37.0％ (10/27) showed strong increased radioactivity only.X-ray found 20 lesions.Twelve cases underwent CT and 7 cases underwent MRI.Abnormal spots showed on CT and MRI were also positive on the whole body bone scan.Conclusions The most common site of BMFH is femur,especially distal femur.BMFH lesions are presented as strong increased radioactivity together with sparse and defect area on bone scan.The whole body bone scan may be an auxiliary examination to evaluate whether there are multiple bone lesions and bone metastasis.