Reduction of Vasoreactivity and Thrombogenicity with Laser-Thermal Angioplasty: Comparison with Balloon Angioplasty

The vasoreactivity and thrombogenicity of laser-thermal angioplasty were examined and compared with those of balloon angioplasty in an atherosclerotic rabbit iliac artery. Eight rabbits underwent laser-thermal angioplasty with a 1.7-mm hot-tip probe activated at 7 W with a probe temperature of 126 +/- 19 degrees C in one iliac artery. The other iliac artery was treated with balloon angioplasty using a 2.0-mm balloon. Angiographic luminal diameter increased from 0.19 +/- 0.15 to 1.54 +/- 0.35 mm by laser and from 0.29 +/- 0.22 to 1.84 +/- 0.20 mm by balloon (P less than 0.0001, respectively). However, it decreased to 1.34 +/- 0.42 for laser and 0.45 +/- 0.39 for balloon 60 minutes later (P less than 0.0001 vs immediately post). Both iliac arteries were visualized using angioscopy, which revealed thrombotic obstruction of 91% stenosis in the ballooned artery and 8% stenosis in the lased artery. Vasoreactivity of treated vessels was also investigated. Segments 3-mm long were obtained from either treated artery or control artery and examined for noradrenaline (10 -7 M) contraction. The segments were then mounted isometrically with 1 g tension in Krebs-bicarbonate buffer. Developed tension was 0.13 +/- 0.21 g for laser thermal and 2.33 +/- 0.4 g for its control (P less than 0.0001), and 0.15 +/- 0.16 g for balloon dilatation and 2.12 +/- 0.43 g for its control (P less than 0.0001). Neither acetylcholine at 10 -6 M or papaverine at 10 -4 M induced relaxation of treated segments. Histology showed slight thermal injury at thermally-treated sites without thrombus, and intimal and medial dissection with thrombus formation at balloon dilated site. In conclusion: (1) neither a laser-thermal recanalized or a balloon dilated obstructed artery is vasoreactive to constrictive or relaxant agents; and (2) laser-thermal angioplasty results in less thrombogenicity than balloon angioplasty under moderate probe temperature.     

Summation and Inhibition by Ultrarapid Train Pulses in Dogs: Effects of Frequency and Duration of Trains, Lidocaine, and Beta Blockade

To test whether summation and inhibition of excitation by ultrarapid train pulses were modified by frequency and duration of trains, using lidocaine and beta blockade, the strength-interval relationship was determined with a single extrastimulus and train pulses (100 and 200 Hz) in 28 anesthetized, open-chest dogs. The effective refractory period (ERP) determined at greater than or equal to 5 mA was shorter for trains than for single stimulus (summation). Summation determined at 15 mA increased progressively as the duration of trains was increased to 50 msec after which it reached a plateau. ERP determined at less than or equal to 2 mA was longer with train pulses than with single stimulus (inhibition). Inhibition for 200 Hz trains increased linearly with train duration up to 200 msec, while for 100 Hz trains it became constant when the duration was greater than or equal to 80 msec. Lidocaine (plasma concentration: 2.6 +/- 1.0 micrograms/mL) did not affect inhibition and summation in 11 dogs. Propranolol (1 mg/kg, iv) increased summation at 15 mA (n = 7, 30 +/- 10 vs 46 +/- 11 msec with 100 Hz trains, P less than 0.01), but did not affect inhibition (37 +/- 26 vs 29 +/- 17 msec, NS). In conclusion, (1) effect of frequency of train pulses was more on inhibition than on summation; (2) lidocaine did not affect inhibition and summation; and (3) propranolol increased summation but not inhibition.     

Clinical features of anti-chromo antibodies associated with anti-centromere antibodies

Anti-chromo antibodies (AChA) are autoantibodies accompanying anti-centromere antibodies (ACA). We determined the frequency and clinical significance of AChA in autoimmune rheumatic diseases. Serum samples from 252 patients with rheumatic diseases were examined by immunoblotting with HeLa nuclear extract and with recombinant N-terminus of 25-kD chromo protein (p25). AChA were detected in 28 (36%) of 77 sera with ACA. AChA were found only in ACA-positive sera. Twenty-two (79%) of 28 recognized a recombinant N-terminal portion of p25, including the chromo domain which is conserved among species. AChA were related to leucopenia, thrombocytopenia, elevated erythrocyte sedimentation rate, and existence of Sjögren*s syndrome (SS). In ACA-positive patients, AChA might be a serologic indicator of systemic sclerosis (SSc), having features of systemic lupus erythematosus and/or SS or diseases other than SSc.     

Effect of Partial Bladder Outlet Obstruction on the Morphology of Elastin in Rabbit Bladder Smooth Muscle

Objectives: Elastin, in association with collagen, allows the body's organs to stretch and relax. Collagen and elastin, the major components of connective tissue, are present throughout the bladder wall and are intimately related to bladder compliance. The present study was undertaken to evaluate elastin morphologically using immunostaining and electron microscopy in the rabbit model of partial bladder outlet obstruction (PBOO). Methods: Four groups of Japanese white rabbits underwent either PBOO by mild ligation of the urethra (2‐ and 4‐week PBOO) or no obstruction (2‐ and 4‐week sham). Histopathological examination was performed by Elastica van Gieson staining, scanning electron microscopy, transmission electron microscopy, and ultra‐high voltage electron microscopy. The number of pixels representing elastin fibers in computerized images was analyzed using Adobe Photoshop Version 2.0. Results: Bladder weight significantly increased after PBOO. Increase in the thickness of the bladder wall was observed after obstruction on histopathological examination. On scanning electron microscopy, elastin was very thick and was found in large configurations. 3‐D analysis using electron microscopic tomography revealed that elastic fibers in the bladder had a coil‐like appearance in the muscle layer, with each fiber composed of several fibrils. Such structures may be closely related to the physiological function of the bladder. Conclusion: Elastin in the bladder assumes the form of a coil during micturition. We examined that the increase in elastin makes it difficult for elastin to stretch linearly resulting in reduced elasticity. This change may be one of the factors involved in the decrease in compliance mediated by PBOO.     

Multicentric liposarcoma

Abstract A 72-year-old man complaining of upper abdominal discomfort was diagnosed as having retroperitoneal liposarcoma by means of diagnostic imaging. He then underwent an operation. One mass existed on the curvatura ventriculi major, extending to the hilum splenicum and pressing back the pancreal head and body. There was another mass to the left of the first, situated on the ventral side of the left kidney. Also, another mass was intramurally found adjacent to the curvatura ventriculi major. Histologically, the mass on the curvatura ventriculi major ranged from the peritoneal cavity to the retroperitoneum Its intraperitoneal portion was classified as a differentiated lipoma-like type and the retroperitoneal mass was of mucous type. The mass on the left kidney was of a differentiated fibrosing type. The intramural mass in the gastric curvature was found to be a differentiated lipoma-like type. The patient has been under observation for 12 months and has shown no recurrence.     

Video analysis of gross body movements during sleep

Abstract Gross body movements (GM) during sleep, classified into four GM types by the involved parts of body, were evaluated using two-dimensional video analysis in five normal children aged 4–12 years. The rate of occurrence of all GM types showed apparent sleep stage dependency. Among four GM types, GM-1 (GM with axial rotation) was the most frequent. Averaged duration of GM-1 was the longest. A total of 77.2% of GM-1 started with the contraction of chin muscle and 35% of total sleep changes (tSC) were related to GM. A total of 5.6% of tSC following GM shifted to the deeper stage. Further evaluation is necessary in order to understand the physiological mechanism of GM.