Malignant glomus tumor: a case report and review of the literature.

This report concerns a malignant glomus tumor, a rare soft tissue tumor that was examined immunohistochemically and ultrastructurally. It occurred in a 44-year-old male patient who had suffered from dull pain and stiffness in the right thigh for 10 months. Radiographic examination revealed a well-defined osteolytic lesion in the diaphysis of the right femur. Hypervascularity of the tumor was observed angiographically. Computed tomographic and magnetic resonance examinations showed an intramuscular mass invading the marrow space of the femur. Wide resection was performed after open biopsy. Histologically, round to polygonal tumor cells revealed a uniform appearance of round to ovoid nuclei with single large nucleoli and slightly eosinophilic cytoplasm, forming solid sheets of cells interrupted by vessels of varying size. A few mitotic figures and vascular invasion were observed. Immunohistochemically, vimentin and alpha-smooth muscle actin were stained intensely, and muscle actin was positive for tumor cells of the perivascular area. Tumor cells were negative for desmin, factor VIII-related antigen, S-100 protein, neurofilament, cytokeratin, and epithelial membrane antigen. Ultrastructurally, tumor cells were characterized by many cytoplasmic processes, pinocytotic vesicles, plasmalemmal dense plaques, and scattered microfilaments in the cytoplasm. Few cell junctions and focal basement membrane-like structures were observed. No recurrence or metastasis was noted 57 months after operation. This case was considered to be a malignant glomus tumor, that is, a glomangiosarcoma arising de novo.

Novel antiasthmatic agents with dual activities of thromboxane A2 synthetase inhibition and bronchodilation. 1. 2-[2-(1-Imidazolyl)alkyl]-1(2H)-phthalazinones.

A number of 4-substituted 2-[omega-(1-imidazolyl)alkyl]-1(2H)-phthalazinones were synthesized in order to develop agents possessing both thromboxane A2 synthetase inhibitory and bronchodilatory activities. The pharmacological evaluation of these compounds disclosed that they have both activities to various extents. Both activities were slightly dependent on the length of the 2-substituents and largely affected by the nature of the 4-substituents. Compounds bearing phenyl and thienyl groups exhibited relatively high and well-rounded activities. Among these compounds, 12j and 15f were found to be the most effective agents having well-rounded activities in vitro and in vivo. Introduction of a carboxyl group reduced both activities contrary to our expectation. 4-(3-Pyridyl)phthalazinone 18b was of particular interest because of unexpectedly high in vivo activities in spite of an absence of significant in vitro activities.

Novel antiasthmatic agents with dual activities of thromboxane A2 synthetase inhibition and bronchodilation. 2. 4-(3-Pyridyl)-1(2H)-phthalazinones.

A series of novel 4-(3-pyridyl)-1(2H)-phthalazinone derivatives which possess dual activities of thromboxane A2 (TXA2) synthetase inhibition and bronchodilation was synthesized, and their pharmacological activities were evaluated. While the length and the bulk of 2-alkyl substituents had no influence on either activity, the 2-substituents with polar groups reduced bronchodilatory activity. Furthermore, we introduced heteroaromatic nuclei into the 4-position of the phthalazinone and found that 1-imidazolyl (13a) and 5-thiazolyl (16b and 16c) derivatives were as active as the parent 3-pyridyl compound 5b. These findings suggest that heteroaromatic nuclei at the 4-position of phthalazinones play a critical role in TXA2 synthetase inhibition. Additionally, the hydrophobicity of the compounds was found to exert a marked influence on bronchodilatory activity. These observations led to the selection of 2-ethyl-4-(3-pyridyl)-1(2H)-phthalazinone (5b) (KK-505) and 2-methyl-4-(5-thiazolyl)-1(2H)-phthalazinone (16b) (KK-562) for further studies. Although their precise mechanism of action remains unclear, this series of novel phthalazinone derivatives represents a new class of antiasthma agents with dual activities.

Novel calcium antagonists with both calcium overload inhibition and antioxidant activity. 2. Structure-activity relationships of thiazolidinone derivatives.

CP-060 (1), 2-(3, 5-di-tert-butyl-4-hydroxyphenyl)-3-[3-[N-methyl-N-[2-[3, 4-(methylenedioxy)phenoxy]ethyl]amino]propyl]-1,3-thiazolidin-4-on e, is a novel type of Ca(2+) antagonist possessing both Ca(2+) overload inhibition and antioxidant activity. The structure-activity relationships for this series of compounds were studied by synthesizing the analogues and evaluating these three kinds of activity. Ca(2+) antagonistic activity was largely determined by the lipophilicity of the phenyl group at the 2-position and the length of the alkyl chains. As for the antioxidant activity, it was demonstrated that the phenolic hydroxyl group is an essential structural element. Compounds with potent activity were evaluated for their effect on the coronary blood flow in vivo. Among these compounds, compound 1 was shown to be the most potent. Furthermore, the enantiomers of 1 were resolved by high-performance liquid chromatography with a chiral column. Compound (-)-1 showed about 10 times higher Ca(2+) antagonistic activity than (+)-1, though both enantiomers had similar potency in Ca(2+) overload inhibition and antioxidant activity. An X-ray crystal structure determination of (-)-1 hydrogen fumarate identified (-)-1 as having S configuration at the 2-position.

Novel calcium antagonists with both calcium overload inhibition and antioxidant activity. 1. 2-(3, 5-di-tert-butyl-4-hydroxyphenyl)-3-(aminopropyl)thiazolidinones.

A series of 2-(3, 5-di-tert-butyl-4-hydroxyphenyl)-3-(aminopropyl)thiazolidinones was synthesized in order to explore novel calcium antagonists with potent antiischemic activity. These compounds were designed to have, in addition to Ca2+ antagonistic activity, both Ca2+ overload prevention and antioxidant activity in one molecule. These three kinds of activity were evaluated by using a K+-depolarized rat aorta, a veratridine-induced Ca2+ overload model of rat cardiomyocytes, and a soybean lipoxygenase-induced lipid peroxidation model of rabbit low-density lipoprotein, respectively. In particular, 2-(3, 5-di-tert-butyl-4-hydroxyphenyl)-3-[3-[N-methyl-N-[2-[3, 4-(methylenedioxy)phenoxy]ethyl]amino]propyl]-1,3-thiazolidin-4-on e (7o) was found to be highly potent and possessed a well-balanced combination of these actions in vitro.

The protective effects of CP-060S on ischaemia- and reperfusion- induced arrhythmias in anaesthetized rats.

1. CP-060S is a novel sodium and calcium overload inhibitor, and is also characterized as a calcium channel blocker. As these activities have each been shown independently to ameliorate ischaemia damage in the myocardium, the combination may synergistically exert cardioprotection. In this study, therefore, the protective effect of CP-060S against ischaemia- and reperfusion-induced arrhythmia was evaluated in anesthetized rats. 2. Rats were anaesthetized with pentobarbitone, and the left anterior descending coronary artery was occluded for either 5 min with subsequent reperfusion (a reperfusion-induced arrhythmia model) or 30 min without (an ischaemia-induced arrhythmia model). All drugs were intravenously administered 1 min before the onset of occlusion. 3. In the reperfusion-induced arrhythmia model, the animals in the vehicle-treated group exhibited ventricular tachycardia (VT) in 100%, ventricular fibrillation (VF) in 89%, and death caused by sustained VF in 56%. CP-060S (30-300 microg kg(-1)) dose-dependently suppressed the incidences of arrhythmias. Significant decreases occurred at 100 microg kg(-1) in VF (incidence: 42%) and mortality (8%), and at 300 microg kg(-1) in VT (50%), VF (33%) and mortality (8%). This protective effect of CP-060S was 10 times more potent than that of a pure calcium channel blocker, diltiazem (30-1000 microg kg(-1)) we tested, in terms of effective dose ranges. As both drugs decreased myocardial oxygen consumption estimated by rate-pressure product to a similar extent, the calcium channel blocking activity of CP-060S would not seem to be sufficient to explain its potency. 4. In the same model, co-administration of ineffective doses of diltiazem (300 microg kg(-1)) and a sodium and calcium overload inhibitor, R56865 (100 microg kg(-1)), produced significant suppression of VT (incidence: 62%), VF (46%) and mortality (8%). By contrast, co-administration of R56865 at the same dose with CP-060S (300 microg kg(-1)) did not add to the effect of a single treatment of CP-060S. 5. In the ischaemia-induced arrhythmia model, CP-060S (300 microg kg(-1)) significantly decreased the incidence of VF from 75% to 29%, whereas diltiazem (1 mg kg(-1)) was ineffective. 6. These results suggest that CP-060S inhibits both ischaemia- and reperfusion-induced arrhythmia. The combination of the calcium channel blocking effect and the calcium overload inhibition was hypothesized to contribute to these potently protective effects.

Neuropathology of familial erythrophagocytic lymphohistiocytosis: six cases and review of the literature.

The authors report the brain findings in six cases of familial erythrophagocytic lymphohistiocytosis (FEL) and review the literature, focusing primarily on the neurologic and neuropathologic aspects. Clinically, the most common neurologic abnormalities in the six patients were stupor or coma and seizures, with hemiplegia and cranial nerve palsies. Neuropathologic changes were characterized by infiltration of the meninges by lymphocytes and histiocytes and perivascular lymphocytic cuffing and diffuse proliferation of histiocytes in the brain parenchyma. The severity of the brain involvement was variable. In the mildest case there was only meningeal involvement. More severely involved cases showed meningeal and perivascular infiltration of lymphoid cells in the brain. In the most severely involved cases, there was, in addition, diffuse cerebral infiltration by histiocytes accompanied by multifocal necrosis. Some cases showed disproportionately greater involvement of the brain than of the visceral organs. The authors conclude that "meningoencephalitis," histiocytic invasion, and necrotizing brain lesions are characteristic of FEL, although the mechanism of their production is not known. Frequent seizures and disseminated intravascular coagulopathy may be contributory.

Craniometaphysial dysplasia with leukoencephalopathy. A case report.

A case of craniometaphysial dysplasia with extensive degeneration of the cerebral white matter is presented. The cortex of the swollen part of the long bones was quite thin and there was striking trabecular atrophy. Both the vault and base of the skull showed marked thickening and sclerosis, leaving no interlaminal zone. It is probable that the diffuse degenerative change of the cerebral white matter with gliosis bears some resemblance to that produced by a circulatory disturbance of the great vein of Galen. Due to the narrowed foramen magnum, deformed atlase and axis, and the surrounding postoperative scar, the upper cervical cord was compressed, markedly atrophic and degenerated. Other segments of the cervical and thoracic cord displayed secondary wallerian degeneration and focal neurolytic lesions in the white matter. At the level of Th11 there was a pencil-like malacic lesion, suggesting an apparent interference of circulatory disturbance due possibly to the deformed vertebral column.

An analysis of the stimulant effects of 5-hydroxytryptamine on isolated, blood-perfused rat heart.

In rat isolated hearts perfused at a fixed low rate, single injections of 5-hydroxytryptamine (5-HT) (0.1--3 microgram) into the coronary perfusion produced dose-dependent increases in left ventricular (LV) dP/dt max and perfusion pressure (PP), but no clear changes in heart rate. The increases in the LVdP/dt max and PP were not significantly affected by treatment with propranolol, while they were abolished by methysergide. The present study indicates that the positive inotropic and vasoconstrictor responses of the rat heart to 5-HT are not mediated by endogenous catecholamine release, but are induced by a direct action on 5-HT receptors.

Analysis of the contractile responses of the ileal segment of the isolated blood-perfused small intestine of rats to adenosine triphosphate and related compounds.

For close-arterial injection the isolated small intestine of the rat was perfused by a cross-circulation technique at a fixed flow rate through the superior mesenteric artery with arterial blood from a donor. Single intra-arterial injections of purine derivatives elicited a monophasic fast contraction of the ileum. In order to elucidate the mechanism of the fast contraction, adenosine triphosphate (ATP) was chosen for further investigations. The ileal response to ATP was abolished by tetrodotoxin, hexamethonium or morphine, but was resistant to blockade by atropine, methysergide or mepyramine. These results definitely indicate that ATP causes the fast contraction of the ileum by a stimulation of neuronal elements in the myenteric plexus involving cholinergic interneurons.

Synergistic effect of calcitonin gene-related peptide on adenosine-induced vasodepression in rats.

The action of calcitonin gene-related peptide (CGRP) on the vasodepressor response to adenosine was investigated in anesthetized rats. I.v. bolus injections of adenosine (1-100 microg/kg), acetylcholine (0.05-0.4 microg/kg), isoproterenol (1-30 ng/kg), nitroglycerin (0.3-10 microg/kg) and diltiazem (10-300 microg/kg) produced dose-dependent decreases in blood pressure, accompanied by changes in heart rate. Only the vasodepressor response elicited by adenosine, among the agents tested, was significantly enhanced by i.v. infusion of either CGRP (1 ng/kg per min) or cromakalim (0.1 microg/kg per min), which possesses glibenclamide-sensitive K+ channel opening activity. After i.v. treatment with glibenclamide (20 mg/kg), the vasodepressor responses not only to adenosine but also to CGRP (0.5 microg/kg) and cromakalim (30 microg/kg) were significantly reduced, while those to acetylcholine and isoproterenol remained unchanged. The result indicates that the enhancement of the adenosine-induced vasodepression by CGRP, like that elicited by cromakalim, seems to be mediated at least partly through ATP-sensitive K+ channel activation.

Is the cardiovascular effect of nitroglycerin related to the prostaglandin system in the dog?

Open-chest dogs were used for studies of the effects of intra-coronary (0.3-10 micrograms) or i.v. nitroglycerin (0.3-100 micrograms/kg) on systemic blood pressure (SBP), heart rate, left ventricular (LV) pressure, coronary blood flow and vascular resistance in the absence of presence of indomethacin (3 mg/kg i.v.). The nitroglycerin-induced changes in the cardiovascular parameters were not significantly modified by indomethacin (3 mg/kg i.v.). The dose of indomethacin used was large enough to inhibit significantly, for more than 2 h, the coronary vasodilation induced by arachidonic acid (100 micrograms) administered intra-arterially. The present study suggests that the cardiovascular action of nitroglycerin may not be mediated through the prostaglandin system.

In vivo experiments for the evaluation of alpha 1-adrenoceptor antagonistic effects of SGB-1534 on canine urethra.

The alpha 1-adrenoceptor blocking effects of SGB-1534 on the urethral smooth muscle were compared in in vivo lower urinary tract preparations of anesthetized dogs, with the effects of other alpha 1-adrenoceptor antagonists, prazosin and bunazosin. Hypogastric nerve stimulation and selective administration of phenylephrine to the urethra and bladder through the cannulated right external iliac artery (i.a.) elicited reproducible frequency- and dose-dependent increases in intra-urethral pressure. Intra-bladder pressure was increased by the nerve stimulation but not by i.a. phenylephrine. SGB-1534, prazosin or bunazosin (0.1-10 micrograms/kg i.v.) dose dependently suppressed the urethral contraction evoked by the nerve stimulation and i.a. phenylephrine but did not influence the bladder contraction elicited by nerve stimulation. The alpha 1-adrenoceptor blocking potency of SGB-1534 was approximately 2.3 and 8.1 times greater than that of prazosin and bunazosin, respectively. The results indicate that alpha 1-adrenoceptors may mediate mainly the urethral contraction induced by hypogastric nerve stimulation and i.a. phenylephrine, and that SGB-1534 was more potent alpha 1-adrenoceptor blocking activity than prazosin and bunazosin in the canine urethra.

Role for adenosine A1 and A2 receptors in femoral vasodilatation induced by intra-arterial adenosine in rabbits.

The vasodilator effects of adenosine injected into the femoral artery (i.a.) of rabbits were analyzed. Single bolus i.a. doses of adenosine (0.3-10 microg) and 5'-(N-cyclopropyl)-carboxamidoadenosine (CPCA) (0.03-1 microg), an adenosine A2-receptor agonist, produced dose-dependent increases in femoral blood flow and decreases in resistance, almost without affecting blood pressure, heart rate, left ventricular (LV) pressure, and LVd P/dt max, even though CPCA elicited slight decreases in arterial blood pressure and LV pressure. On the other hand, bolus i.a. injections of N6-cyclopentyladenosine (CPA) (1-30 microg), an adenosine A1 receptor agonist, caused a relatively weak increase in blood flow, but markedly affected cardiac parameters, especially heart rate and LVd P/dt max. I.v. treatment with 3,7-dimethyl-1-propargylxanthine (DMPX)(2 mg kg(-1)), an antagonist of adenosine A2 receptors, or 8-phenyltheophylline (1 mg kg(-1)), an antagonist of adenosine A1 receptors, significantly attenuated the vasodilator response to adenosine, but not that to acetylcholine. Decreases in blood pressure, heart rate, LV pressure, LVdP/dt max and femoral vascular resistance, and increases in the blood flow elicited by CPA were not significantly modified by the DMPX treatment, but when this was combined with 8-phenyltheophylline, the responses to CPA were completely abolished. The present results indicate that the adenosine-induced femoral vasodilatation in rabbits may be mediated throughout activation of both adenosine A1 and A2 receptors.

Actions of CP-060S on veratridine-induced Ca2+ overload in cardiomyocytes and mechanical activities in vascular strips.

CP-060S, (-)-(S)-2-[3,5-bis(1, 1-dimethylethyl)-4-hydroxyphenyl]-3-[3-[N-methyl-N-[2-(3, 4-methylenedioxyphenoxy)ethyl]amino]propyl]-1,3-thiazolidin- 4-one hydrogen fumarate, is a novel cardioprotective drug which is designed to prevent Ca2+ overload and cause vasorelaxation. The effects of this compound were evaluated and compared with those of CP-060R (enantiomer of CP-060S,) and diltiazem (Ca2+ channel antagonist) in a veratridine-induced model of Ca2+ overload and vasorelaxation. After 5-min superfusion of veratridine (74 microM), intracellular free calcium concentrations ([Ca2+]i) of rat single cardiomyocytes, as measured with the fura-2 procedure, were greatly elevated, from 44 +/- 5 nM to 3705 +/- 942 nM, and subsequently generated cell contracture. Pretreatment of cardiomyocytes with more than 300 nM of CP-060S or CP-060R for 30 min provided almost complete protection against the veratridine-induced cell contracture; in CP-060S(1 microM)-treated myocytes, [Ca2+]i were minimal and partially elevated from 42 +/- 5 nM to 72 +/- 14 nM after 5 min of veratridine superfusion. In comparison, diltiazem showed no protection below 1 microM and only partial protection at 10 microM. CP-060S, CP-060R and diltiazem all shifted the concentration-response curve for CaCl2 to the right in a competitive manner in depolarized rat thoracic aorta. The pA2 values of CP-060S, CP-060R and diltiazem were 9.16 +/- 0.18, 8.24 +/- 0.14 and 7.66 +/- 0.09, respectively. Our results indicate that CP-060 behaves stereoselectively as a Ca2+ channel antagonist and non-stereo-selectively to protect against veratridine-induced contracture. The latter effect suggests that Ca2+ entry blockade is not the mechanism by which CP-060S exerts cardioprotection.

Vasoconstriction after adenosine and inosine in the rat isolated hindlimb abolished by blockade of tryptaminergic mechanisms.

The isolated right hindlimb of the rat was perfused at a fixed flow rate through the femoral artery with heparinized blood from the carotid artery of a donor. Single injections of adenosine (1--300 microgram) induced a biphasic response, a long-lasting vasoconstriction preceded by a transient vasodilatation. Inosine (1--300 microgram) produced only vasoconstriction. After repeated administration of 300 microgram of these substances, the vasoconstriction became less prominent, and finally reverted to vasodilatation. The vasoconstrictor response to these substances (300 microgram) was also diminished or reverted to vasodilatation after pretreatment with reserpine or methysergide. From these results, it is concluded that vasoconstriction after adenosine or inosine may be mediated by 5-hydroxytryptamine released from the peripheral stores and that the intrinsic direct action of these substances on the femoral vascular bed is vasodilator.

Effects of CP-060S, a novel cardioprotective drug, in the methacholine-induced ECG change model in rats.

We compared the antianginal effect of CP-060S, a novel cardioprotective drug with Na+ and Ca2+ overload-preventing activity as well as Ca2+ channel antagonistic activity, with that of diltiazem, in an experimental model of vasospastic angina induced by methacholine in anaesthetized rats. Intra-aortic injection of methacholine at the coronary ostium provoked the ST-segment elevation of the electrocardiogram (ECG), indicating myocardial ischemia. CP-060S (3, 5 and 10 mg/kg, i.d.) significantly and dose-dependently suppressed the methacholine-induced ST-elevation, with the duration of action being at least 3 h at the highest dose. In addition, CP-060S at 3 mg/kg could inhibit the ST-elevation without producing significant changes in blood pressure, heart rate or rate-pressure product (RPP). In contrast, diltiazem (10 and 30 mg/kg, i.d.) significantly decreased the RPP, a significant suppression of the ST-elevation could only be achieved at the highest dose and its duration of action was about 2 h. Similar results were obtained with i.v. administration of the drugs, i.e. CP-060S given i.v. could inhibit the ST-elevation with less haemodynamic changes than diltiazem. In conclusion, CP-060S exerted a more potent and sustained protection against myocardial ischemia evoked by methacholine than diltiazem. The characteristics of the effects of CP-060S observed here suggest that this drug may be a desirable drug for the treatment of vasospastic angina.

A research method for MRI tissue characterization studies using small coils for excised organs.

The main purpose of this report is to describe our method of MRI tissue characterization studies, which consists of MR imaging of the patient, precision MR imaging of the excised organ, and pathological examination of the organ. We first made small coils to be used with conventional MRI scanners to examine the excised organs. In order to make it easier to understand the effectiveness of our method, three illustrative case reports of abdominal or pelvic tumors were presented as examples of the tissue characterization studies. In conclusion, this method seemed very useful and, in addition, it was found that this small coil technique has several advantages in other applications.

Differential effects of nicorandil on the vasodepressor responses to vasoactive polypeptides administered intravenously to rats.

The effects of nicorandil on vasodepressor responses to vasoactive intestinal polypeptide (VIP), calcitonin gene-related peptide (CGRP) and substance P have been examined in anaesthetized rats. Intravenous bolus injections of VIP (0.3 microg kg(-1)), CGRP (0.1 microg kg(-1)) and substance P (0.1 microg kg(-1)) induced reductions of blood pressure accompanied by slight increases (less than 5%) in heart rate. Nicorandil infused intravenously at 10 or 30 microg kg(-1) min(-1) significantly augmented the vasodepressor responses to VIP and CGRP but did not modify the responses to substance P and acetylcholine (0.1 microg kg(-1)). Intravenous treatment with glibenclamide (20 mg kg(-1)) [corrected] significantly attenuated not only the vasodepression caused by VIP and CGRP, but also the enhancement of the effects of the agents by nicorandil. These results indicate that nicorandil can enhance the action of VIP and CGRP, in rats, at least partly through ATP-sensitive K+-channel activation.

Hypotensive effects and biotransformation of nicorandil, a new antianginal agent, administered to rats by different routes: comparison with nitroglycerin and isosorbide dinitrate.

The effects of nicorandil, N-(2-hydroxyethyl)nicotinamide nitrate (ester), in reducing systemic blood pressure (SBP) in rats were studied in comparison with isosorbide dinitrate and nitroglycerin. The drugs were administered to pentobarbitone-anaesthetized rats by jugular vein (i.v.), portal vein (p.v.), intrajejunal (i.j.), intraperitoneal (i.p.) and subcutaneous (s.c.) routes. Nicorandil was absorbed rapidly through all routes, and caused marked hypotension dose-dependently. With isosorbide dinitrate and nitroglycerin, unlike nicorandil, the p.v. dose required to induce a vasodepressor response was significantly greater than that required to cause a comparable response after i.v. administration. In non-recirculating rat liver perfusion experiments, nicorandil was reduced only 5-10% during a single passage through the liver, while nitroglycerin was reduced over 95%. In recirculating liver perfusion experiments, the progressive decrease of nicorandil in the blood recirculated was accompanied by a corresponding increase of SG-86, a dinitrate compound of nicorandil (its main metabolite). Sixty min after dosing, nicorandil was decreased by approximately 73% of the initial nicorandil blood concentration and SG-86 was increased by approximately 70%. The extent of degradation of nicorandil in liver homogenates, examined by thin-layer chromatography, was in the following order: rat = guinea-pig greater than dog = monkey greater than pig. In these species a close inverse relationship is apparent between the rate of liver nicorandil degradation and hypotensive effects of nicorandil.