This study was designed to investigate the effect of substitution of strontium for calcium on mechanical activity in isolated perfused spontaneously beating rat hearts. The mechanical activity of the hearts of Langendorff's preparation in conditions of low calcium and strontium-substitution for calcium was compared. The effect of norepinephrine and verapamil were also observed in those conditions. The results were as follows: 1. In low calcium, the mechanical activity of the heart preparation was significantly reduced, but when the equimolar strontium was substituted for the reduced calcium, the activity was kept at similar level to the normal condition. 2. When equimolar strontium was substituted for the total calcium in perfusate, the heart preparation stopped its beating, and it was not restored in spite of reperfusion with normal calcium perfusate. 3. Norepinephrine-induced positive inotropic effect was inhibited in low-calcium condition especially with low concentration of norepinephrine, but not in strontium-substitution for calcium. 4. Verapamil reduced the activity of the heart both in low-calcium and strontium-substitution as well as in normal calcium conditions. From above results, it was concluded that strontium served as a substitute of calcium in maintaining mechanical activity and in responsiveness to norepinephrine, and the influx of strontium through cell membrane is inhibited by verapamil as the influx of calcium.
Animals ; Calcium ; Cell Membrane ; Heart* ; Norepinephrine* ; Rats* ; Reperfusion ; Strontium* ; Verapamil

No abstract available.
Humans

No abstract available.

PURPOSE: The purpose of this study is to evaluate the findings of magnetic resonance imaging(MRI) of posterior fossa hemangioblastoma and usefulness of contrast enhancement with Gd-DTPA. MATERIALS AND METHODS: Seven patients with posterior fossa hemangioblastoma were studied with both pre- and post-enhanced MRI. The MR images were reviewed regarding the location, size, signal intensities of cysts and mural nodules, and their contrast enhancement pattern. RESULTS: Five tumors were located in cerebellar hemisphere, one in vermis, and one in posterior part of medulla. One patient with von HippeI-Lindau disease had a medullary hemangioblastoma with multiple pancreatic cysts. In 6 cases, the major portion of the tumor was cysts and had small mulkal nodules. The solid portion was relatiely lange in one case, cemprising half of the tumor Cysts were oval shaped and their sizes were 3--6.7cm in diameter. In five cases(71%), septations were noted within the cysts. Cysts were isointense or slightly hyperintense on Tl-weighted image and hyperintense on T2-weighted image compared with cerebrospinal fluid. Mural nodules were oval or rounded appearance in five cases and flattened appearance in two, and their size was 0.5--2.5cm in diameter. Mural nodules were isointense to gray matter. They were detected in five cases on Tl-weighted images and one case on T2-weighted images. In two cases, vascular signal void area was noted in mural nodules. On contrast-enhanced Tl-weighted images, all mural nodules were intensely enhanced. CONCLUSION: MRI proved to be a good diagnostic method to detect and characterize posterior fossa hemangioblastoma. The most common finding is Cystic posterior fossa lesion with enhancing mural nodule. Contrast enhancement is essential for specific diagnosis.
Cerebrospinal Fluid ; Diagnosis ; Gadolinium DTPA ; Hemangioblastoma* ; Humans ; Magnetic Resonance Imaging* ; Pancreatic Cyst

As one of many cell-many cell-based cartilage repairing methods, transplantation of chondrocyte-embedded-collagen gels in cartilage defect was performed for more satisfactory regeneration of cartilage. The authors performed this study to investigate whether the TGF-beta1 treatment of chondrocytes can do some additional synergistic effect on the transplantation of chondrocyte-embedded-collagen gels for crtilage repair. Chondrocytes were isolated from the articular cartilage of newborn Sprague-Dawley rats. Chondrocytes cultured for 10 days in monolayer were embedded in the 0.45% type I collagen gel. Full-thickness cartilage defect was made in the patellar groove of adult Sprague-Dawley rats. Chondrocytes culdefect was made in the patellar groove of adult Sprague-Dawley rats. The cartilage defects were treated with the following methods in a total of 200 animals, which were assigned to 5 different groups of 40 rats. In the control group, the deffect was left without any treatment, in group I, the defect was filled with collagen gel only, in group II, with collagen gel coontaining 10 ng/ml concentration of TGF-beta1, in group III, with collagen gel containing chondrocytes, and in group IV, with collagen gel containing chondrocytes and TGF-beta1. At 1, 2, 4, 8, 12 weeks after the operation, eight rats of each group were sacrificed, and their distal femurs were harvested for the histologic and biomechanical tests. The section s were stained with hematoxilin and eosin. Alcian-blue, and Safranin-O. Regenerated cartilage was analyzed by the semiquantitative histological grading system. Point indentation test was performed as a biomechanical evaluation, and the stiffness was calculated. The results of the histological grading system revealed that the scores gradually increased with time in all groups, and the scores of group III and IV were higher than those of control, group I and II. The biomechanical study showed that the stiffness gradually increased to reach a plateau level in each group. In control, group I and II, the stiffness increased up to the eighth week and remained around the increased level at the twelfth week, and did not show any statistically significant difference between the groups. In group III and IV, the stiffness was higher than in control group, and increased markedly at the fourth week and the increased level was maintained onwards. The results of this study showed that the transplantation of chondrocyte-embedded-collagen gels enhanced the healing process, and the treatment of TGF-beta1 demonstrated at least partially significant improvement.
Adult ; Animals ; Cartilage ; Cartilage, Articular* ; Chondrocytes ; Collagen ; Collagen Type I ; Eosine Yellowish-(YS) ; Femur ; Gels ; Humans ; Infant, Newborn ; Rats* ; Rats, Sprague-Dawley ; Regeneration ; Transforming Growth Factor beta1

No abstract available.
Child* ; Hematuria* ; Humans ; Jeollabuk-do* ; Prevalence*

This study was performed to investigate the effect of octreotide on the contractility of rat vas deferens. The -smooth muscle strips isolated from the prostatic portion were myographied in isolated organ bath. Electric -field stimulation (monophasic square wave, duration : 1. mSec, voltage : 50 V, frequency : 5 Hz or 30 Hz, train : 10 Sec) produced reproducible contraction. The contraction was composed of two component, first phasic component (FPC) and second tonicc component (STC).. These contractions were abolished by -tetrodotoxin (1 microM). Octreotide inhibited the field stimulation induced contractions both FPC and STC concentration- dependently. The FPC was decreased by a desentization of purinergic receptor by pretreatment of mATP, and the STC was decreased by pr,,creatment of reserpine (3 mg/kg, EP) 24 hours before experiments. Octreotide reduced the field stimulation induced contraction in the presence of mATP and of reserpinized muscle strips. The inhibitory effect of octreotide was more potent at 5 Hz than at 30 Hz. Octreotide did not affect basal ton and exogenous norepinephrine- or ATP-induced contraction. These results suggest that octreotide inhibit the contractility of the isolated rat vas deferens by inhibition of the release of neurotransmitters, both ATP and norepinephrine from adrenergic nerve terminal.
Adenosine Triphosphate ; Animals ; Baths ; Neurotransmitter Agents ; Norepinephrine ; Octreotide* ; Rats* ; Reserpine ; Vas Deferens*

Poor R-Wave Progression(PRWP) of precordial leads is frequently encountered electrocardiographic findings of uncertain significance and has simply been deemed as suggestion of anterior myocardial infarction without concrete ground. 217 cases with poor R-Wave Progression have been analyzed on clinical records and results are as follows. 1) PRWP was most frequently found in fifties and sixities, comprising 63.9% of the subjects. 2) Co-existent disease entities with PRWP were classified into three categories, cardiovascular diseases, chronic lung diseases and normal variants. 3) The cardiovascular diseases related with PRWP were mainly hypertensive diseases, comprising 59.8% of cardiovascular diseases, followed by ischemic heart disease, valvular heart disease and cardiomyopathies. 4) PRWP may be an early sign of acute myocardial infarction in a certain part of cases, which was endorsed by typical clinical symptoms and enzyme studies. 5) As the criterion of PRWP, V3R equal to or less than 3 mm was thought more adequate for higher specificity rather than 4 mm.
Cardiomyopathies ; Cardiovascular Diseases ; Electrocardiography ; Heart Valve Diseases ; Lung Diseases ; Myocardial Infarction ; Myocardial Ischemia ; Sensitivity and Specificity

No abstract available.
Animals ; Interleukin-2 ; Mice*

No Abstract Available.