Reactive oxygen species (ROS) have the potential to damage cellular components, such as protein, resulting in loss of function and structural alteration of proteins. The oxidative process affects a variety of side amino acid groups, some of which are converted to carbonyl compounds. We have previously shown that a prostaglandin D2 metabolite, 15-deoxy-delta(12,14)-prostaglandin J2 (15d-PGJ2), is the potent inducer of intracellular oxidative stress on human neuroblastoma SH-SY5Y cells [Kondo, M., Oya-Ito, T., Kumagai, T., Osawa, T., and Uchida, K. (2001) Cyclopentenone prostaglandins as potential inducers of intracellular oxidative stress, J. Biol. Chem. 276, 12076-12083]. In the present study, to elucidate the molecular mechanism underlying the oxidative stress-mediated cell degeneration, we analyzed the protein carbonylation on SH-SY5Y cells when these cells were submitted to an endogenous inducer of ROS production. Upon exposure of SH-SY5Y cells to this endogenous electrophile, we observed significant accumulation of protein carbonyls within the cells. Proteomic analysis of oxidation-sensitive proteins showed that the major intracellular target of protein carbonylation was one of the regulatory subunits in 26 S proteasome, S6 ATPase. Accompanied by a dramatic increase in protein carbonyls within S6 ATPase, the electrophile-induced oxidative stress exerted a significant decrease in the S6 ATPase activities and a decreased ability of the 26 S proteasome to degrade substrates. Moreover, in vitro oxidation of 26 S proteasome with a metal-catalyzed oxidation system also confirmed that S6 ATPase represents the most oxidation-sensitive subunit in the proteasome. These and the observation that down-regulation of S6 ATPase by RNA interference resulted in the enhanced accumulation of ubiquitinated proteins suggest that S6 ATPase is a molecular target of ROS under conditions of electrophile-induced oxidative stress and that oxidative modification of this regulatory subunit of proteasome may be functionally associated with the altered recognition and degradation of proteasomal substrates in the cells.

The tribological properties of cast iron have been investigated to determine the effects of micro-texturing the surfaces. The micro-textured surfaces were prepared by shot blasting or milling using a shaper. The surfaces with groove patterns and mesh patterns had higher friction coefficients than the flat surfaces. The surfaces with dimpled patterns had lower friction coefficients than the flat surfaces. The results indicated that the dimpled pattern had a beneficial effect by decreasing the friction.

Imaging with 18 F-FDG PET/CT is able to reveal vascular inflammation, and several studies have shown that increased 18 F-FDG uptake in carotid artery plaques can qualify the degree of atherosclerotic inflammation. However, clinical assessment of acute aortic dissection (AAD) by PET/CT remains largely unexplored. This study aimed to investigate the use of 18 F-FDG PET/ CT to predict short-and midterm outcomes in medically controlled AAD patients. Methods: A total of 28 medically treated AAD patients (2 Stanford type A and 26 type B, aged 69.5 6 11.6 y) were prospectively studied. All patients were examined by enhanced CT for diagnosis of AAD and underwent serial imaging studies during follow-up. PET/CT images were acquired 50 and 100 min after 18 F-FDG injection in all patients in the acute phase. Results: Of the 28 patients, 8 who had an unfavorable outcome due to death from rupture (n 5 2), surgical repair (n 5 4), and progression of dissection (n 5 2) were categorized as having unfavorable AAD. The remaining 20 patients were categorized as having favorable AAD. Maximum dissection diameter in the unfavorable group was significantly greater than that in the favorable group (P 5 0.0207). On 50-min images, maximal and mean standardized uptake values (SUVs) at maximum aortic dissection sites were significantly greater for the unfavorable group than for the favorable group (all P , 0.01). A stepwise-forward selection procedure demonstrated that the mean SUV at sites of maximum aortic dissection on 50-min images significantly and independently predicted an unfavorable outcome for AAD (P 5 0.0171; odds ratio, 7.72; 95% confidence interval, 1.44-41.4; R 2 5 0.2372). A mean SUV greater than 3.029 had significant predictive power, with sensitivity of 75.0%, specificity of 70.0%, a positive predictive value of 50.0%, a negative predictive value of 87.5%, and accuracy of 71.4%. Conclusion: Greater uptake of 18 F-FDG in AAD was significantly associated with an increased risk for rupture and progression. 18 F-FDG PET/CT may be used to improve AAD patient management, although more studies are still needed to clarify its role in this clinical scenario. Acut e aortic dissection (AAD) is a life-threatening condition that arises from an atherosclerotic lesion in the aorta and is a leading cause of mortality (1). Current outcomes of medical therapy for Stanford type B AAD remain poor, with early mortality ranging from 10% to 12% (2,3). Medical management for AAD, particularly for Stanford type B, poses the difficult problem of deciding on whether surgery is needed and when it should be performed. The decision should balance the surgical risk and the hazard of aortic rupture in elective cases of Stanford type B AAD and in the elderly (4). Close, long-term CT monitoring of morphologic parameters, including maximum aortic diameter and the shape of the dissection, is helpful both for preventing aortic rupture and for undertaking timely surgical or endovascular intervention (5). However, only the relative and not the individual risk of...

The nodule detection performance on the LCD monitors with a spatial resolution higher than a matrix size of 1,024x1,280 was found to be equivalent to that on the high-resolution CRT monitor.