Effect of Chronic Alcohol Consumption on Phosphatidylcholine Hydroperoxide Content of Rat Liver and Brain

Purpose: To investigate the correlation between alcohol-induced oxidative stress and tissue phosphatidylcholine hydroperoxide (PC-OOH) content of rat liver and brain.Methods: Ten Wistar rats were divided into two groups: one group was given 20 % ethanol (5 g/kg) and the other the same volume of normal saline, orally once a day for 6 weeks. Catalase activity, malondialdehyde (MDA) content, total antioxidant capacity (TAC) and PC-OOH content of liver and brain were determined.Results: The ethanol-treated group had lower catalase activity and total antioxidant capacity. MDA level in the liver was 0.33 ± 0.07 μM/mg protein which is significantly (p < 0.05) higher than that of the control group (0.17 ± 0.06 μM/mg protein), but in brain, there was no significant difference. PC-OOH level in the ethanol-treated group was 46.91 ± 12.87 pmol/mg in liver and 71.97 ± 26.12 pmol/mg protein in brain while PC-OOH level of control group was 21.40 ± 10.71 pmol/mg protein in liver and that in brain was 25.29 ± 5.67 pmol/mg protein pmol. Thus, PC-OOH levels in both liver and brain were significantly (p < 0.05) higher than that of control group. PC-OOH content in the liver and brain correlated significantly (p < 0.05) with catalase activity and total antioxidant capacity (TAC).Conclusion: The study demonstrates that PC-OOH content in liver and brain tissues may be a marker for alcohol-induced oxidative stress.Keywords: Alcohol Toxicity, Oxidative Stress, Phosphatidylcholine Hydroperoxide, Liver, Brain, Biomarke

Synchrotron X-ray microtomography for 3D imaging of polymer blends

Despite sufficient spatial resolution and routine operation, traditional electron microscopy (SEM and TEM) of polymer blend morphologies is limited to two dimensions (2D) and often requires tedious sample preparation. We have used a powerful X-ray imaging technique to visualize the morphology of polymer blends in three dimensions (3D). Images of polystyrene/high-density polyethylene (PS/HDPE) blend samples were constructed with microtomography using coherent synchrotron X-rays. Good contrast for blends with and without the PS phase removed (no other sample preparation was needed) was accomplished, and image quality is compared in the paper. High resolution (1 mu m) images of relatively thick (similar to 1 mm) blend samples were possible by adapting a sample stage equipped with high precision motor controls, by enhancing phase contrast through optimization of sample-scintillator distance, and by taking a large number of projection images (up to 1000) along different angles. Reconstructed slices were used to create 3D volume-rendered images of the blends. Coarsening of the cocontinuous morphology during annealing was monitored using extraction-free microtomography. Measurements of interfacial area per volume at varying annealing times agree with experimental results obtained using mercury porosimetry. It was also shown that SEM quantitative annealing results are limited at long annealing times due to the limitations of two-dimensional images of a three-dimensional morphology.X114442sciescopu

Imaging of renal and prostate carcinoma with refractive index radiology

Aim: Having better edge enhancement and penetrating power, refractive index radiology is suitable for the imaging of weakly absorbing objects such as tissue specimens. In this study the potential of refractive index radiology was evaluated for the imaging of renal cell carcinoma (RCC) and prostate cancer (PCA). Methods: Specimens were cut in 3 mm and 4 mu m thickness for X-ray radiology and hematoxylin and eosin (HE) staining, respectively. Radiographic images of RCC and PCA were obtained using the synchrotron hard X-rays from the 7B2 beam-line of the Pohang Light Source (PLS). The imaging technique applied was phase-contrast radiology based on the refraction enhancement mechanism. The resulting radiographic images were analyzed in correlation with those of optical microscopy. Results: Using unmonochromatized hard X-rays, it was possible to obtain images with clear edge enhancement and relatively large field of view (6 cm x 6 cm). Even with overlapping signals from thick samples (more than 700-fold thicker than microscopic images), radiographic images clearly showed histological information of organelles in normal kidney such as glomeruli, tubules, and collecting ducts. Histological information of RCC including tumor subtypes and minute changes such as cystic degeneration could be identified without difficulty. The radiographic images of the prostate were comparable with those of low magnification optical microscopy, providing good visualization of normal microstructures such as adenoma, smooth muscle, and normal glands, or differentiation of tiny tumors from surrounding normal tissues. Conclusions: These results suggest the potential of refractive index radiology to provide a new way of imaging biological tissues with low absorption contrast such as RCC and PCA.X1110sciescopu