In vitro keratinization of normal human salivary gland cells.
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Biomedical subjects
Publications and source records attributed to S Imai.
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Pure prostatic leiomyoma is very rare. We report a case of magnetic resonance imaging findings of prostatic leiomyoma. The mass was expansile and had a slightly higher signal intensity than skeletal muscle on T2-weighted images. Normal prostatic glandular tissue could be clearly distinguished from the tumor.
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The Department of Radiology of the Shinshu University Hospital is presently in the process of developing a new type of mini-PACS with a hybrid architecture consisting of a video and a digital image archiving network. The video block consists of a server station with a video write-once optical disk (LD) and three workstations which are connected to two ultrasound imaging devices and an MRI device. The video images from any of these imaging devices are transferred immediately onto an LD. The examiner can observe the archived images immediately without any interruption of the examination. The image transmission time, including the record and play-back, is within 3 s. The digital block consists of a personal computer server and various workstations linked to the ETHERNET. This digital system supports database management, and archives digital images. This prototype system was used for daily clinical examinations from February 1989 to January 1990 and 31,366 images from 1561 patients were stored on the video disk. This one year experience suggests that a hybrid mini-PACS system is practical for total image archiving when the image matrix is less than 512 x 512 and selected digital image archiving.
Effects of ethanol ingestion on allylamine-induced subendocardial fibrosis of the myocardium and intimal hyperplasia of the intramyocardial coronary artery were investigated in male Wistar rats. The toxic effect of allylamine is ascribed to acrolein produced from allylamine by benzylamine oxidase. Animals were forced to drink allylamine solution for 12 weeks. Incidence and size of subendocardial fibrosis were examined, and the lesions of the intramyocardial artery were scrutinized. Effects of ethanol on the systemic blood pressure and benzylamine oxidase activity were investigated in another experiment. Treatment with allylamine resulted in subendocardial fibrosis (size = 4.2%) in 4 of 12 rats. The incidence of fibrosis was increased (up to 6/12) and the area of fibrosis was augmented (to 6.8%) in animals additionally treated with epinephrine. The lesions in the intramyocardial vasculature were also augmented. Ethanol ingestion reduced allylamine-induced subendocardial fibrosis and intramyocardial coronary lesions. The effects were significant in animals additionally treated with epinephrine. Systemic blood pressure and benzylamine oxidase activity were not significantly affected by allylamine or by ethanol. The vasodilatory effect of ethanol may have prevented the development of microvascular spasm induced by allylamine.
The shoulder capsule and labrum of Japanese macaque monkeys were studied immunohistochemically with the use of antisera against protein gene product 9.5 (PGP 9.5), calcitonin gene-related peptide (CGRP), and substance P (SP) to further characterize the innervation of the supporting structures of the shoulder joint. With PGP 9.5 immunohistochemistry thick nerve fibers (diameter > or = 10 microm) presumed to be proprioceptive based on topographic location were found to be abundant in the posterior half of the capsule. Thinner fibers (diameter <10 microm) presumed to contain nociceptive and autonomic fibers were located in the posterior half of the capsule. Ruffini-like corpuscles were predominantly located in the inferior portion of the capsule. SP and CGRP immunoreactive thin fibers presumed to be nociceptive were abundant in the posterior half of the capsule. Thin fibers that appeared to be nociceptive fibers were found in the marginal portion and the parenchyma of the labrum, although the number was small. The predominant distribution of the Ruffini-like corpuscles in the inferior portion of the capsule suggest an important role of the inferior portion in generation of the proprioceptive output, which should be advantageous in stabilization of the joint in motion. The abundance of nociceptive fibers in the posterior half of the capsule may be responsible for the pathophysiological transmission of pain around the shoulder joint.
MR studies of five chondrosarcomas and three enchondromas were performed with intravenous Gd-DTPA administration. All tumors showed enhancement of scalloped margins and curvilinear septa (ring-and-arc pattern) on T1-weighted SE sequences with Gd-DTPA. On radiologic-pathologic correlation, the enhanced areas corresponded to fibrovascular bundles surrounding hyaline cartilage lobules. The rings and arcs of enhancement with Gd-DTPA on MR is a reflection of the lobulated growth pattern of cartilaginous tumors and therefore helpful in differential diagnosis of bone tumors.
We present three giant cell tumors of bone that contained large amounts of hemosiderin and compare their MR appearance with intraoperative findings and histological characterization. Histologically, hemosiderin was found in multinucleated giant cells, mononuclear stromal cells, and xanthoma cells. All cases showed markedly decreased signal areas on both T1- and T2-weighted MR imaging due to hemosiderin deposition; this made evaluation of the integrity of the adjacent cortices difficult. In one case, extraosseous tumor extension appeared as a signal void area on MR imaging. Findings on immunohistochemical studies suggested the giant cells may have a histiocytic nature. Because the tumor cells themselves have a phagocytic nature, the decreased signal areas in and around giant cell tumors should be regarded as active tumor tissues in delineating the tumor on MR imaging.
We compared the beta-adrenoceptor blocking actions of bupuranolol and propranolol using the response to isoprenaline of the strength of contraction of the canine blood-perfused ventricular muscle, of the rate and strength of contraction of the isolated guinea pig heart and of a guinea pig tracheal ring preparation. The potency ratios of bupuranolol to propranolol were 3.6, 3.0, 3.4, and 2.4, respectively. Bupuranolol decreased the maximum dV/dt of the canine ventricular action potential and had no sympathomimetic action. Bupuranolol effectively suppressed halothane-adrenaline ventricular arrhythmias in the dog, reflecting its potency as a beta-adrenoceptor antagonist. In contrast, bupuranolol did not suppress ventricular arrhythmias induced by two-stage coronary ligation in the dog. Compared to propranolol and certain other antiarrhythmic drugs, bupuranolol had weaker effects on prolonging the effective refractory period than on the maximum dV/dt of canine ventricular muscle. This suggests that lengthening of the refractory period may be important for suppressing the two-stage coronary ligation arrhythmia and that the mechanism of this arrhythmia might be reentry.
Since Ca-mediated electrophysiological phenomena seem to be important in the generation of various arrhythmias, we quantitatively compared the effects of quinidine, disopyramide, procainamide, lidocaine, propranolol, and etafenone, a new coronary vasodilator with antiarrhythmic properties, on Na and Ca channels in normal and depolarized guinea pig atria. The maximum rate of rise of the normal action potential and the amplitude of the depolarized, Ca-mediated action potential were measured to examine the Na and Ca channel activity, respectively. In both preparations, the contractile force was determined concomitantly in order to establish the role of Ca influx in the inotropic effects of the drugs. All six drugs suppressed the Na channel, the effect being strongest with etafenone, followed in order by quinidine, propranolol, disopyramide, lidocaine, and procainamide. Only quinidine, disopyramide, and propranolol suppressed the Ca channel and only in concentrations higher than those required to block the Na channel. Etafenone and procainamide decreased Ca influx, while lidocaine had no effect on it. The negative inotropic effects of propranolol and disopyramide may be due to decreases in Ca influx, but the order drugs seem to have other mechanisms for their inotropic effects.
The effects of parathyroid hormone and related polypeptides on the heart were examined using the canine heart-lung preparation supported by a donor. Synthetic bovine parathyroid hormone (PTH) containing 34 amino acids [PTH-(1--34)] and natural bovine PTH containing 84 amino acids [PTH-(1--84)] showed slight positive chronotropic and inotropic action and prominent coronary vasodilator action. The effects of the two compounds were very similar. The cardiac stimulatory action was not blocked by pindolol. The coronary vasodilation occurred without increase in the myocardial oxygen consumption, suggesting that it is due to a direct action on the coronary vasculature. All effects occurred soon after intra-arterial injection, lasted only about 20 min, and were not accompanied by changes in plasma Ca and Pi levels. Fragments of PTH, PTH-(24--34) containing 11 amino acids. PTH-(24--28) containing 5 amino acids, and PTH-(25--27) containing 3 amino acids showed very weak transient coronary dilatory action without cardiac stimulatory effects.
Using 31P nuclear magnetic resonance (NMR) spectroscopy (acquisition time of 3 min), we studied the effects of l- and d-propranolol on the ischemic derangement of myocardial energy metabolism in the isolated perfused guinea pig heart. The myocardial pH and concentration of high-energy phosphate were used as measures of the energy metabolism. Cardiac pH progressively declined during ischemia from 7.41 +/- 0.04 to 7.13 +/- 0.05, 6.91 +/- 0.04, 6.74 +/- 0.04, and 6.61 +/- 0.04 (before ischemia and 3, 6, 9, and 12 min after ischemia, respectively). After 3 min of reperfusion, pH rapidly returned to 7.42 +/- 0.04. Creatine phosphate (CP) and adenosine triphosphate (ATP) contents were reduced, while inorganic phosphate (Pi) contents were increased during ischemia. Whereas CP and Pi contents were restored to the normal values after reperfusion, the recovery of ATP contents was poor. Both l- and d-propranolol (10(-6) M) significantly suppressed the fall of the myocardial pH. Changes in the high-energy phosphate contents were also attenuated by l- and d-propranolol. These results suggest that not only l-propranolol, but also d-propranolol can produce beneficial effects on the ischemic derangements of myocardial energy metabolism.
We determined the minimum effective plasma concentrations of several antiarrhythmic agents against canine halothane-adrenaline arrhythmia. Sustained ventricular tachycardia was produced by continuous adrenaline infusion at rates of 1.5 to 4 micrograms/kg/min under 1.5% halothane anesthesia. Procainamide, 20 mg/kg, produced ventricular fibrillation in three of nine dogs. Disopyramide, 3 mg/kg, suppressed the arrhythmia in nine of 11 dogs at a minimum effective plasma concentration of 4.2 micrograms/ml, but produced ventricular fibrillation in the remaining two dogs. Phenytoin, 5 mg/kg, was effective at a minimum concentration of 12 micrograms/ml. Lidocaine, 10 mg/kg, suppressed the arrhythmia at a minimum concentration of 15 micrograms/ml, which is much higher than the human toxic plasma level. These drugs may have suppressed the adrenaline arrhythmia by inhibiting the sodium channel, because their effective concentrations were very close to membrane-stabilizing concentrations in vitro. Small doses of 30 micrograms/kg propranolol and 0.1 mg/kg N-696, two beta-blockers, and 0.1 mg/kg verapamil, a calcium channel blocker, yielding a concentration of 0.03 micrograms/ml, suppressed the arrhythmia, probably by indirectly or directly blocking the calcium channel.
In the canine heart-lung preparation (HLP) and the anesthetized open-chest dog, both 8-(Benzylthio)-N6-n-butyl-cyclic AMP (BTB-cyclic AMP) (10 times more potent) and dibutyryl-cyclic AMP (DB-cyclic AMP) produced a definite positive inotropic effect (PIE) and an increase in the coronary blood flow with either no change (HLP) or a slight increase (anesthetized animal) (BTB-cyclic AMP) and a definite increase in the heart rate (DB-cyclic AMP). In the isolated atrial preparations of the guinea pig (AG), BTB-cyclic AMP produced a slight PIE at 3 X 10(-5) M and a negative chronotropic effect at 3 X 10(-4) M. Aminophylline reversed the latter to the positive one, while potentiating the former. At 10(-3) M marked positive inotropic and chronotropic effects were observed. DB-cyclic AMP was without effects. In the right ventricular papillary muscle preparations of the guinea pig (PMG), both compounds produced PIE. BTB-cyclic AMP initiated a contraction (AG) and a "slow" action potential (PMG) in partially depolarized preparations. Both of these effects were abolished by diltiazem. BTB-cyclic AMP (10(-3) M) suppressed the heart rate increase induced by isoproterenol in right AG. It was concluded that BTB-cyclic AMP was a cardiotonic agent with a relatively weak positive chronotropic effect and that the cardiotonic effect was ascribable to the initiation of slow action potentials and related contractions.
A 67 year old male with non-resectable hepatocellular carcinoma (HCC) in both lobes and liver cirrhosis was treated with transcatheter arterial embolization and regional chemotherapy. He was doing well for 18 months. He was readmitted for fever, chest pain and multiple pulmonary metastases. During interleukin-2 therapy, he suddenly developed dyspnoea and palpitation, and was in shock. Left-sided haemothorax was confirmed by draining 3 L of fresh blood. In spite of intensive care, he died within 36 h. Autopsy showed that the haemothorax was caused by rupture of one of the metastases in the upper lobe of the left lung, and that the primary HCC was totally necrotic. Survey of the literature failed to find a report of fatal bleeding from a lung metastasis of HCC.
The composition of the rumen ciliate fauna in 76 Kafue lechwe inhabiting a limited area in Zambia was surveyed and five genera containing 24 species with 16 formae belonging to the family Ophryoscolecidae were identified. Four new species belonging to Diplodiniinae were recognized and described as Diplodinium lochinvarense n. sp., Diplodinium leche n. sp., Diplodinium zambiense n. sp., and Metadinium ossiculi n. sp. In addition, Ostracodinium gracile form fissilaminatum Dogiel, 1932 was found for the second time and described as Metadinium fissilaminatum n. comb. The species composition was fairly unusual. Seven of the species have been found only in African wild antelopes and these species were found more frequently than cosmopolitan species. There was no evidence of isotrichid species. The average density of ciliates per 1 ml of the rumen fluid was 25.7 x 10(4), and the number of ciliate species per head of host was 10.8.
Isotricha jalaludinii n. sp. found in the rumen of lesser mouse deer, Tragulus javanicus, in Malaysia was described and illustrated. This new species is characterized by the location and direction of the vestibulum, shape of the macronucleus, and absence of a dent at the vestibular opening. The presence of single peculiar isotrichid species in the rumen of mouse deer, which is recognized as one of the most primitive ruminants, suggests that the isotrichid ciliates similar to I. jalaludinii and Isotricha intestinalis were established at a fairly early period during the evolution of ruminants.
Composition of rumen ciliate fauna in five Zambian, sassaby antelopes was determined. Six genera, 18 species, and four forms were identified. One new species and form, belonging to the subfamily Diplodiniinae, were found, then labeled Ostracodinium damaliscus n. sp. and Diplodinium bubalidis f. aspinosum n. f., respectively. Only ophryoscolecid species were present while isotrichids were absent. Twelve of 18 total species are commonly found in African antelopes. Three of those 12 species, Entodinium fyferi, Enoploplastron garstangi and Opisthotrichum janus, are only found in African antelopes. Percentage composition was low in the genera Enoploplastron, Eudiplodinium and Entodinium, and high in the genus Opisthotrichum. The average density of ciliates was 3.1 x 10(5)/ml of rumen fluid, and the average number of ciliate species per host was 17.2.