Aspirin and salicylate enhances the induction of inducible nitric oxide synthase in cultured rat smooth muscle cells

Aspirin and sodium salicylate enhance to a similar extent the production of nitric oxide (NO) in cultured smooth muscle cells following stimulation by interleukin-1beta (IL-1beta). The similar potencies of aspirin and sodium salicylate indicate that acetylation of cellular macromolecules is not essential for the enhancement of NO production. The failure of added prostaglandin E2 (PGE2) or Thromboxane A2 (TXA2) to overcome the effects of aspirin or sodium salicylate indicates that these effects are not simply the result of inhibition of prostaglandin synthesis. The enhancement of NO production occurs dependent of the effects of these agents on induction of inducible nitric oxide synthase (iNOS) expression by IL-1beta. Aspirin and sodium salicylate enhance the induction of iNOS expression by IL-1beta. We previously reported that pretreatment of vascular smooth muscle cells (VSMCs) with high glucose decreased the response of the cells by IL-1beta, that is, the induction of iNOS expression and NO production. We investigated the effect of aspirin and sodium salicylate on the response by IL-1beta of VSMCs pretreated with high glucose (25 mM). Aspirin and sodium salicylate ameliorate the down-regulation of iNOS expression and the decrease of NO production caused by pretreatment with high glucose (25 mM). These results suggest a possible therapeutic role in atherosclerotic disease and diabetes mellitus for aspirin and sodium salicylate by enhancing the level of iNOS expression and NO production.     

Structure-activity relationships of spontaneous nitric oxide releasers, FK409 and its derivatives

(+/-)-(E)-4-Ethyl-2-[(E)-hydroxyimino]-5-nitro-3-hexenamide (FK409) shows both potent in vitro vasorelaxant and antiplatelet activities via nitric oxide (NO) generated spontaneously from the compound. In this study, we measured spontaneous NO-releasing rates of a series of FK409 derivatives, of which chain lengths or substituents were systematically modified, in sodium-phosphate buffer solution at pH 7.4. Furthermore, we studied their in vitro antiplatelet and vasorelaxant effects to evaluate relationships between spontaneous NO-releasing activities of FK409 analogs and their biological activities. FK409 derivatives were found to possess different spontaneous NO-releasing rates and biological activities according to their structural modification. In addition, these studies revealed a close correlation between NO-releasing rates of FK409 derivatives and their in vitro antiplatelet activities in human platelet-rich plasma, whereas the in vitro vasorelaxant activities of these compounds in isolated rat aorta did not correlate with the rates of NO liberation. The vasorelaxant effects were supposed to be affected by the structural properties of FK409 derivatives as well as their NO-releasing abilities.     

Materials evaluation of diffusion bonded steel bar and its impact characteristics

When we apply non-destructive test for evaluating the soundness of weld joints it is necessary to know the mechanical properties of the joints by destructive test. In this paper we tried to obtain the correlation between the data by ultrasonic C-scope method and the absorbed energy by Charpy impact test for diffusion bonded steel bars. The surface roughness of specimens (materials: S25C, mild steel) used for the diffusion bonding was changed into several steps by machining and the diffusion bonding was performed on five kinds of combinations of the surface roughness. Through this process we obtained the diffusion bonds whose ratio of non-bonded area was different. In the ultrasonic test we used the frequency of 10 MHz and a transducer of 12.7 mm in diameter. The ratio of non-bonded area is obtained by using C-scope method by immersion testing, and this depended on the threshold echo level when we binarized the images of C-scope presentation and the surface roughness of the specimen. The lower the threshold echo level, the larger the ratio of non-bonded area. The absorbed energy depended on the ratio of non-bonded area. It is made clear that the proper threshold echo level should be selected for evaluating the soundness of diffusion bonds by ultrasonic test. Moreover, when the transition liquid phase diffusion bonding was performed on SD345 (deformed reinforcing steel bar) using Ni amorphous foil as an insert metal the absorbed energy also decreased with the increase in the ratio of flaw area obtained by ultrasonic test, though no change in the tensile strength was observed.     

Simultaneous measurement of surface tension and kinematic viscosity using thermal fluctuations

We have developed a surface laser-light scattering apparatus to measure simultaneously surface tension and kinematic viscosity. In this method, we can obtain the surface properties by the laser heterodyne detection of light scattered from thermally excited capillary waves (called ripplon), which are typically of low amplitude (1 nm) and a characteristic wavelength (100m). Two gratings (d=100 and 200m) were employed to select the wave number of the capillary waves and to produce a reference beam for heterodyne detection. It was found through an experimental study on water that this contact-free method has considerable potential for application to measurements under extreme conditions such as high temperatures and high pressures.Paper presented at the Twelfth Symposium on Thermophysical Properties, June 19–24, 1994, Boulder, Colorado, U.S.A.     

Preparation of highly oriented thin film exhibiting transparent conduction by the sol-gel process

Highly oriented thin films exhibiting transparent conduction aluminium-doped ZnO (AZO), were prepared by a spin-coating method. The effects of the solvents on the preparation and electrical properties of the thin films were examined. The thin films were formed on quartz glass substrates by spin-coating into a selected solution and calcining at 700 °C for 5 h. The thin films had a resistivity of ( cm)=1.5 after heat treatment in an air atmosphere, and 1.5 × 10^–3 cm in a reducing atmosphere, and a transmission of about 85% in the visible light region. The differences in the high orientation and the conductivities were attributed to a chelate formation in the aluminium-doped ZnO due to the solvent effect.     

Glial tumourettes (glial microtumours): their clinical and histopathological manifestations

This study represents our experience with eight cases (males: 4; females: 4; 13-47 years old, average age 28.5 years) of a "glial tumourette" (minute glioma), which measured less than 15 mm in diameter on an MRI. Four tumours were located in the frontal lobe, one in the rostrum of the corpus callosum, two in the midbrain, and one in the thalamus. The symptoms and signs lasted from two days to 15 months prior to diagnosis, and they consisted of epileptic seizures in five patients and increased intracranial pressure due to hydrocephalus resulting from aqueductal stenosis in three. All patients had a CT scan and an MRI as a part of their initial neuroimaging evaluations. While the CT findings failed to show the lesion in four patients, MRI demonstrated it in all cases. Five tumours were either totally or subtotally removed while the remaining three were biopsied. Histological examinations revealed six tumours to be low-grade gliomas (fibrillary astrocytoma: 4; oligoastrocytoma: 2) and two to be high-grade gliomas (anaplastic astrocytoma: 1; anaplastic oligodendroglioma: 1). Regarding adjuvant therapy, three patients received radiation and/or chemotherapy. One of the patients with midbrain fibrillary astrocytoma died of the disease 38 months after the operation, however, no evidence of progression in the remaining seven has been observed in the follow-up period ranging from five to 65 months after the operation (average: 25.4 months). The histogenesis of benign and malignant gliomas and the importance of surgical exploration in the management of such patients with minute intracerebral tumours are also discussed.     

Photo-induced super-hydrophilic property and photocatalysis on transparent Ti-containing mesoporous silica thin films

The transparent Ti-containing mesoporous silica thin films can be prepared on quartz plate using a spin-coating sol–gel method. The spectroscopic characterization has revealed that the Ti-containing mesoporous silica thin films contain isolated and tetrahedrally-coordinated titanium oxide moieties in the frameworks. Compared with the common mesoporous silica thin films, these Ti-containing mesoporous silica thin films have demonstrated a strong hydrophilic surface property even before UV-irradiation. After UV-light irradiation, the contact angle of water droplet on the Ti-containing mesoporous silica thin films became lower, indicating the appearance of the super-hydrophilic property. Under UV-light irradiation Ti-containing mesoporous silica thin films also exhibited highly selective activity for the photocatalytic oxidation of propylene. The isolated and tetrahedrally-coordinated titanium oxide moieties are responsible for these photo-induced surface reactions.