Effects of 1-(2,6-dimethylphenoxy)-2-(3,4-dimethoxy phenylethylamino) propane hydrochloride on cytosolic free calcium concentration of rabbit platelets

The effects of 1-(2, 6-dimethylphenoxy)-2- (3,4-dimethoxyphenylethylamino) propane hydrochloride (DDPH) and verapamil on cytosolic free calcium concentration of rabbit platelets were investigated. The results showed that the elevation of cytosolic free calcium concentration ([Ca2+]i) of rabbit platelets following ionophore A23187 was significantly inhibited by DDPH and verapamil. The rates of inhibition with DDPH and verapamil were 58% and 78%, respectively, with no significant difference between the two groups (P > 0.05).     

Inverse effect of chronically elevated blood flow on atherogenesis in miniature swine

The effect of chronically elevated blood flow on the development of atherosclerosis in miniature swine was studied. Fistulas connecting the right external iliac artery and vein were surgically created in four swine, while three were not fistulated. Pulsed Doppler velocity detection cuffs placed around the abdominal aorta and both iliac arteries of all pigs permitted chronic measurements of blood velocity, blood velocity distributions, and blood flow. All swine were fed an atherogenic diet consisting of 20% beef tallow, 3% cholesterol, and 5% cholic acid for 6 months. This diet elevated the serum cholesterol to values exceeding 500 mg/100 ml. Creation of the arteriovenous fistula (AVF) markedly elevated blood velocity and flow in the abdominal aorta and in the shunted iliac artery. In the shunted animals the aortic blood flow was 42.1 +/- 2.0 ml/sec compared with 17.3 +/- 1.4 ml/sec in the unshunted swine. The velocity distribution pattern across the vessel was also indicative of an elevated wall shear stress. After 6 months, the animals were killed and the arterial vessels examined macroscopically and microscopically for the presence of atherosclerotic lesions. In the shunted pigs, 17 +/- 15% of the lumenal surface was occupied by sudanophilic lesions, whereas 80 +/- 8% of the surface was covered by lesions in the unshunted (control) pigs. From these studies, it is apparent that mechanical factors related to blood flow rates can influence the development of atherosclerotic lesions in swine.     

Monolithically integrated multiwavelength sampled grating DBRlasers for dense WDM applications

For accurate control of the channel spacing in fabricating multiwavelength laser arrays or discrete multicolor lasers, we proposed a novel approach that exploits sampled grating distributed Bragg reflector (DBR) mirrors to vary the laser wave length across the wafer. This approach can realize a set of lasers with a wavelength spacing that meets the ITU recommendations for dense wavelength-division multiplexing systems and a wavelength range that can cover up to 40 nm or more. The wavelength variation across an array is achieved by changing the sampling periods of the DBR mirrors from laser to laser. The accuracy on the channel spacing of sampled grating DBR laser arrays was shown to be the same as that of conventional distributed feedback or DBR laser arrays, but their wavelengths can be better controlled for the gratings are fabricated with single holographic exposure. Arrays of 21 lasers have been successfully fabricated and have around 0.8-nm wavelength spacing with a simple tuning mechanism