Objective To investigate the relationship between the expressions of P-gp, GST-π and C-erbB-2 and clinicopathologic characteristics as well as prognosis in breast cancer. Methods The expressions of P-gp， GST-π and C-erbB-2 were detected by immunohistochemistry in 48 cases of breast cancer, and histopathologic characteristics as well as 5-year survival rate of these cases were analyzed. Results There was no significant difference in the expressions of P-gp and GST-π with age, histologic grade, number of lymph node metastasis and TNM stage of breast cancer ( P ＞ 0.05). There was significant difference in expression of C-erbB-2 with histologic grade, number of lymph node metastasis and TNM stage of breast cancer （ P ＜ 0.05）. Positive rate of P-gp expression in breast cancer with positive C-erbB-2 expression was remarkably higher than that in breast cancer with negative C-erbB-2 expression ( P ＜ 0.05) . Positive rate of GST-π and C-erbB-2 expression in survivals within 5 years was remarkably lower than that in deaths within 5 years ( P ＜ 0.01). Conclusion P-gp participates primary drug-resistance mechanism of breast cancer. The possibility of primary drug-resistance is higher in breast cancer with positive C-erbB-2 expression. The expression of C-erbB-2 helps to evaluate prognosis and the result of treatment in breast cancer.
In order to choose the appropriate antibiotics for treating secondary pancreatic infection, permeability of antibiotics to pancreatic tissue was investigated on experimental dogs with acute hemorrhagic necrotizing pancreatitis. The concentrations of 8 different antibiotics were determined in the blood and the pancreatic tissue using highperformance liquid chromatography. Pancreatic tissue permeability of Cefotaxime, Ofloxacin, Amikacin, Piperacllin, Cefoperazone, Ampicillin, Metronidazole and Ciprofloxacin was 12%, 19%, 20%, 46%, 55%, 63%, 71% and 132% respectively. The study shows that this eight antibiotics have different permeability to the pancreatic tissue. Such observations support the existence of a bloodpancreas barrier, which acts to restrict the permeation of antibiotics into the pancreas. The results suggest that antibiotics with high permeability rate be used to treat the patient with secondary pancreatic infection.
Objective To observe the change of diffusion upper limit of macromol ecules through pathological retina and the difference between the layers of retina. Methods Retinal edema was emulated by establishing branch retinal vein occlusion (RVO) model in miniature pig eyes under photodynamic method. Two days later, the retinas of both eyeballs were peeled off. The diffusion test apparatus was designed by ourselves. FITC-dextrans of various molecular weights (4.4, 9.3, 19.6, 38.9, 71.2 and 150 kDa) and Carboxyfluorescein (376 Da) were dissolved in RPMI1640 solutions and diffused through inner or outer surface of retina. The rate of transretinal diffusion was determined with a spectrophotometer. Theoretical maximum size of molecule (MSM) was calculated by extrapolating the trend-linear relationship with the diffusion rate. In separate experiments to determine the sites of barrier to diffusion, FITC-dextrans were applied to either the inner or outer retinal surface, processed as frozen sections, and viewed with a fluores cence microscope. Results FITC-dextrans applying to inner retinal surface, 4.4 kDa dextrans were largely blocked by inner nuclear layer (INL); 19.6,71.2 kDa dextrans were blocked by the nerve fiber layer (NFL) and inner plexiform layer; 15.0 kDa dextrans were blocked by NFL. FITC-dextrans applying to outer retinal surface, most dextrans with various molecular weights were blocked before outer nuclear layer (ONL). No matter applying to the inner or outer surface, Carboxyfluore scein can diffuse through the whole retina and aggregate at INL and ONL. After RVO, the inner part of retina became edema and cystoid, loosing the barrier function. Compared with the normal retina, the MSM in RVO tissues increased (6.5plusmn;0 39nm Vs 6.18plusmn;0.54nm, t=4.143, P=0.0001). Conclusions A fter RVO, the barrier function of inner part of retinal is destroyed and the upper limit of diffusion macromolecule size increased, which is nevertheless limited. ONL acts as bottle-neck barriers to diffusion, if the outer part of retina is damaged, the change of the diffusion upper limit will be prominent. （Chin J Ocul Fundus Dis，2008，24：197-201）
Triply periodic minimal surface (TPMS) is widely used because it can be used to control the shape of porous scaffolds precisely by formula. In this paper, an I-wrapped package (I-WP) type porous scaffolds were constructed. The finite element method was used to study the relationship between the wall thickness and period, the morphology and mechanical properties of the scaffolds, as well as to study the compression and fluid properties. It was found that the porosity of I-WP type scaffolds with different wall thicknesses (0.1 ~ 0.2 mm) and periods (I-WP 1 ~ I-WP 5) ranged from 68.01% ~ 96.48%, and the equivalent elastic modulus ranged from 0.655 ~ 18.602 GPa; the stress distribution of the scaffolds tended to be uniform with the increase of periods and wall thicknesses; the equivalent elastic modulus of the I-WP type scaffolds was basically unchanged after the topology optimization, and the permeability was improved by 52.3%. In conclusion, for the I-WP type scaffolds, the period parameter can be adjusted first, then the wall thickness parameter can be controlled. Topology optimization can be combined to meet the design requirements. The I-WP scaffolds constructed in this paper have good mechanical properties and meet the requirements of repairing human bone tissue, which may provide a new choice for the design of artificial bone trabecular scaffolds.