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N Kaneko

Publications and source records attributed to N Kaneko.

At least 91 records · Page 5Linked to original sources
PubMed1993

[A case of metastatic iris tumor from lung cancer presenting as decreased vision].

We presented a case of metastatic iris tumor from lung cancer first presenting as decreased vision. A 47-year-old male was referred to our hospital, complaining of decreased vision. At his first visit, a yellowish mass was found on the right iris, and chest X-ray revealed paratracheal, subcarina, and right hilar lymphadenopathy. Bronchoscopy was performed, and small cell carcinoma was detected in a transbronchial biopsy specimen. Sixteen cases of metastatic iris tumor from lung cancer have been reported of such rare occurrences in Japan. The clinical features are briefly reviewed.

Carcinoma, Small Cell↗
PubMed1993

[A case of pulmonary arteriovenous fistulas (PAVF) treated with detachable balloon embolotherapy].

A case of pulmonary arteriovenous fistulas (PAVF) treated with detachable balloon embolotherapy is reported. A 31-year-old man was admitted to hospital because of polycythemia and hypoxemia. He had a history of dyspnea on exertion and transient cerebral ischemic attacks (TIA). Chest roentgenogram revealed a peripheral lobulated lesion in the right upper lung field and a coin lesion in the left lung field connected by dilated blood vessels to each hilus. Pulmonary angiography and right heart catheterization was performed. Four PAVFs were observed in bilateral lung field, and the intrapulmonary shunt ratio was 25.8%. Because the patient was symptomatic, we embolized each PAVF with a detachable balloon without complications. After embolotherapy, there was improvement in his symptoms. hypoxemia and shunt ratio. Recent reviews have highlighted the need to consider embolotherapy for bilateral multiple PAVF. We conclude that embolotherapy with detachable balloon is a very useful procedure for treatment of bilateral multiple PAVF.

Adult↗
PubMed1992

Accelerated purine nucleotide degradation by anaerobic but not by aerobic ergometer muscle exercise.

The exact conditions under which exercise causes purine nucleotide degradation are not well understood. We determined plasma hypoxanthine and uric acid levels serially in eight individuals during ergometer muscle exercise. When the load was increased gradually by 15 W/min, plasma hypoxanthine was elevated only after the status exceeded the anaerobic threshold (AT), as determined by analysis of expired gas. Nonstrenuous ergometer exercise, which kept the status continuously below the AT, induced neither blood lactic acid nor plasma hypoxanthine elevation. These results suggest that the AT is also the threshold for the acceleration of purine nucleotide degradation. Muscle exercise to a degree that does not exceed the AT does not cause major purine nucleotide degradation, and, therefore, is expected to be beneficial for patients with gout and/or hyperuricemia.

Adult↗
PubMed1992

The response to drug therapy in unstable angina on the basis of coronary angiography findings.

Among 366 unstable angina pectoris patients at our hospital, myocardial infarction was common (15.7%) in those with attacks of chest pain lasting for at least 20 min. There was also a high incidence (30.3%) when chest pain continued after the start of inpatient treatment. To investigate the etiology of unstable angina, coronary arteriography was performed in both the unstable and stable stages in these patients and the results were compared. The role of coronary spasm and coronary thrombosis in unstable angina was investigated, and the efficacy of continuous infusion of either diltiazem or isosorbide dinitrate as treatment for these patients was compared. Coronary arteriography in the unstable stage showed, no clear differences in the morphology of the stenotic site and the degree of stenosis between the patients with and without infarcts when urokinase or isosorbide dinitrate were injected into the coronary arteries. When drug treatment was effective, the angina was stabilized without any improvement in the degree of stenosis or the morphology of the involved coronary vessel. Thus, it was difficult to predict the response to treatment from coronary arteriography performed in the unstable stage. Diltiazem was more effective than isosorbide dinitrate, and it appears that some action other than coronary dilatation was involved in achieving the remission of unstable angina.

Angina, Unstable↗
PubMed1992

[The acute and chronic effects of bunazosin on exercise capacity estimated by the anaerobic threshold in patients with chronic congestive heart failure].

To study the effect of bunazosin on exercise capacity in patients with congestive heart failure (NYHA II-III), anaerobic thresholds (AT, VO2, ml/min/kg) were measured before (control) and after initial 1 = 2mg administration of bunazosin (acute phase; N = 14) and after two weeks of bunazosin therapy (3mg/day, 1mg t. i. d., chronic phase; N = 6). AT were determined by Wasserman's V-slope method during ergometer exercise test with a ramp loading (10 watt/min). AT increased significantly from control during both acute (14.2 +/- 2.7 to 16.9 +/- 3.6 ml/min/kg p < 0.005) and chronic (13.6 +/- 2.5 to 16.7 +/- 1.0 p < 0.05) phase. Additionally, work (watt) attained at AT increased significantly from control during both acute (33.6 +/- 19.2 to 52.6 +/- 30.2 p < 0.005) and chronic (35.8 +/- 25 to 49.3 +/- 15 p < 0.05) phase. Pressure-rate-products (PRP, x 10(2) mmHg/min) at AT increased significantly from control during the acute phase (119 +/- 35 to 240 +/- 50 p < 0.005) alone. In the chronic phase, PRP decreased significantly at the work level equal to AT during control (from 207 +/- 41 to 187 +/- 39 p < 0.05). These data suggest that bunazosin has favorable acute and chronic effects on exercise capacity in patients with congestive heart failure.

Adult↗
PubMed1991

Schistosoma mansoni: higher free proline levels in the livers of infected mice.

The concentration of L-hydroxyproline in the liver of ICR female mice increased rapidly during the 8th to 11th weeks of Schistosoma mansoni infection. Free L-proline concentration began to increase about the 7th week and reached its maximum at the 8th to 9th weeks of the infection, when the granulomatous response to the schistosome eggs in the liver was most prominent, as indicated by the increase in liver wet weight and its deoxyribonucleic acid concentration. A significant increment in the total activity of ornithine-delta-transaminase (EC 2.6.1.13) and the decrease in the specific activity of proline oxidase (EC 1.4.3.2) became detectable in the liver homogenate of infected mice on the 8th week. However, changes in these enzymatic activities were not parallel to that of the hepatic free L-proline content. Intraperitoneal administration of S. mansoni egg granulomas or 15,000g x 30 min supernatant fluid of their extracts into uninfected, normal mice significantly increased the hepatic free L-proline content without any appreciable effect on the enzymatic activities of proline oxidase and ornithine-delta-transaminase. These findings suggest that S. mansoni egg granulomas contain a factor(s) which may be responsible for the elevation of free L-proline content in the fibrotic liver caused by experimental schistosomiasis mansoni.

Animals↗
PubMed1991

Induction of kinetic cell death and its underlying mechanisms.

Using a modified Langendorff system, we established an experimental model of kinetic cell death in the rat heart. After calcium (5.5 mM) was loaded for 20 min and 10(-7) mol isoproterenol was then delivered to the perfusion medium, the hearts developed tonic contracture. Histological examination of the myocardium revealed widespread kinetic cell death. Stimulation of alpha-adrenoceptors with phenylephrine did not induce kinetic cell death, even after calcium loading. In our kinetic cell death model in the rat, the outflow of creatine phosphokinase into the perfusion medium was increased after isoproterenol application, with a peak occurring at 45 min. The peak transient increase in the intracellular calcium ion concentration (the Ca-transient) was measured using Fura2/AM, and was found to be augmented by increasing the calcium concentration of the perfusion medium. These results suggest that in the presence of an increased intracellular calcium concentration, even slight stimulation of beta-adrenoceptors can easily induce myocardial injury.

Animals↗
PubMed1991

Clinical and pathologic studies on contraction band lesion: relation to acute myocardial infarction and unexplained sudden death.

The relation between contraction band lesion (CBL) and major cause of death was investigated through the use of hearts from 500 serialized autopsy cases. Acute myocardial infarction (AMI), unexplained sudden death (USD), cardiac surgery death, cancer, infection, cerebrovascular disease, and ruptured aortic aneurysm were examined with respect to age, sex, heart weight, and CBL localization patterns. CBL was observed frequently with AMI, USD, and cardiac surgery death, but virtually unseen with cancer or in the remaining disease categories. In a comparison of average heart weight among the various groups, there appeared to be a correlation between heavy heart weight and increased frequency of CBL. In a second investigational phase, the relation between CBL and application of cardiopulmonary resuscitation techniques was investigated in 100 separate autopsy cases. There was no significant difference between treated and untreated patients regarding frequency and pathology of CBL. We hypothesize that CBL-AMI and CBL-USD belong to the same disease group and that CBL develops before the onset of death with no connection to the mechanical and pharmacologic effects of cardiopulmonary resuscitation.

Adolescent↗
PubMed1990

Human peroxisomal L-alanine: glyoxylate aminotransferase. Evolutionary loss of a mitochondrial targeting signal by point mutation of the initiation codon.

The amino acid sequence of human hepatic peroxisomal L-alanine: glyoxylate aminotransferase 1 (AGTI) deduced from cDNA shows 78% sequence identity with that of rat mitochondrial AGTI, but lacks the N-terminal 22 amino acids (the putative mitochondrial targeting signal). In humans this signal appears to have been deleted during evolution by a point mutation of the initiation codon ATG to ATA. These data suggest that the targeting defect in primary hyperoxaluria type 1, in which AGT1 is diverted from the peroxisomes to the mitochondria, could be due to a point mutation that reintroduces all or part of the mitochondrial signal sequence.

Alanine Transaminase↗
PubMed1990

A case of lipoprotein glomerulopathy. Light and electron microscopic observations of the glomerulus.

A 41-year-old Japanese woman with lipoprotein glomerulopathy is reported. The patient presented with nephrotic syndrome, hyperlipoproteinemia and an increased level of plasma Apo E. The damaged glomeruli showed various degrees of capillary dilatation and accumulation of some material-often showing stratification, along with mesangial proliferation and mesangial interposition. The accumulated material was stained positive for beta-lipoprotein by the indirect immunoperoxidase technique. Capillary dilatation resulted from gradual accumulation of the lipoprotein as well as destruction of the mesangium, as if being torn off, due to increased intraluminal pressure. The patient's eldest sister also suffers from the same renal disease, suggesting a hereditary predisposition.

Adult↗
PubMed1990

Turner's syndrome--review of the literature with reference to a successful pregnancy outcome.

A 30-year-old Japanese female with Turner's syndrome had become pregnant and delivered a normal male infant by cesarean section. Her menarche was at age 14, and secondary sex characteristics developed normally. She had some features of Turner's syndrome, and cytogenetic studies from peripheral blood lymphocytes and several tissues revealed only 45,XO karyotype without evidence of mosaicism. To our knowledge, she is only the thirteenth case of monosomy X to achieve pregnancy. A review of the literature indicates a high incidence of fetal wastage and increased chromosomal errors in the offspring of women with a 45,XO cell line with or without mosaicism.

Adult↗
PubMed1990

[Effects of indomethacin on calcium release from cultured rat calvaria].

The bone-resorbing action of lipopolysaccharides (LPS) in vitro has unknown mechanism of action. In order to evaluate the effect of LPS on rat calvaria and the influence of LPS on the bone-resorbing activity of macrophages, the following experiments were conducted. The addition of macrophages 10(6)/ml to a culture system composed of rat calvaria increased calcium release from the cultured bone. Addition of macrophages 10(6)/ml preincubated with 10(-2) mg/ml LPS caused a more pronounced release of calcium from the cultured bone. Combined use of Indomethacin, a prostaglandin synthesis inhibitor, with macrophages and macrophages preincubated with LPS inhibited calcium release, suggesting a possible participation of prostaglandins in osteoclast mediated bone resorption.

Animals↗
PubMed1989

Schistosoma mansoni: suppression of carbamoyl phosphate synthetase (ammonia) and ornithine carbamoyltransferase activities in the liver of infected mice.

ICR female mice infected with cercariae of Schistosoma mansoni exhibited a significant decrease in both total and specific activities of carbamoyl-phosphate synthetase (ammonia) (EC 6.3.4.16) and ornithine carbamoyltransferase (EC 2.1.3.3), and also in the serum urea level. Intraperitoneal administration of the S. mansoni egg granulomas or 15,000g X 30 min supernatant fluid of their extract into the uninfected, normal mice also significantly decreased the total and specific activities of both enzymes without any appreciable histopathological influence on their livers. S. mansoni viable eggs caused a significant decrease in the total and specific activities of carbamoyl phosphate synthetase (ammonia) alone as well as active intraperitoneal inflammation when inoculated into the normal mice by the same route. There was no difference in the amount of food intake between the control and these experimental mice. These findings suggest that the granuloma or inflammatory cells induced by schistosome eggs produce some factor(s) which may be responsible for reduction of these enzymatic activities in experimental schistosomiasis mansoni.

Animals↗
PubMed1989

Malignant luteoma in a sow.

A case of malignant luteoma was found in a 3-year-old Landrace sow. A large neoplastic mass was present in the left ovary and small neoplastic nodules were seen in the right ovary. There were metastatic lesions in the diaphragmatic peritoneum and heart. The neoplastic cells were extremely pleomorphic and among them relatively large cells predominated. The neoplastic cells had lipid droplets, membranous structures, intermediate filaments and lipofuscin granules in their cytoplasm.

Animals↗
PubMed1989

Appearance of osteoclasts by injections of lipopolysaccharides in rat periodontal tissue.

The effect of lipopolysaccharides (LPS) on periodontal tissue was studied in 11-week-old Wistar rats. Four injections of 500 micrograms LPS induced marked osteoclastic alveolar bone resorption, whereas no alveolar bone resorption occurred after four injections of physiological saline. The osteoclast count increased progressively during the four injections of 500 micrograms LPS. After eight injections, however, the osteoclast count fell from the maximum level after four injections, although osteoclasts continued to increase in size and demonstrate an increased number of nuclei. Comparison of the osteoclast number between a series of four injections of 5, 50 or 500 micrograms LPS each revealed a dose-dependent increase. This strongly suggests LPS induction of osteoclastic bone resorption in vivo. Combined use of indomethacin, a prostaglandin synthesis inhibitor, with LPS injections inhibited both the LPS-induced alveolar bone resorption and osteoclast increase, suggesting a possible participation of prostaglandins in osteoclast-mediated bone resorption.

Animals↗
PubMed1989

[Effects of various doses of monocrotaline administration on the development of pulmonary hypertension and its regression in rats].

We observed the time course of hemodynamic and pathological changes after single injection of various dose of monocrotaline (Mct) to investigate the dose-dependent effects on the induction and regression of pulmonary hypertension in rat: A hundred four-week old male Sprague-Dowley rats were divided into five groups and each group, except the control group, received 10 mg, 20 mg, 30 mg or 40 mg/kg Mct, respectively. The experimental periods were nine weeks after monocrotaline injection. At the third, sixth and ninth week after treatment, the survival rate, cardiac catheterization and pathological changes were evaluated. All rats given 30 mg or 40 mg per kg of Mct died within five weeks. In the third week after the treatment, elevation of the right ventricular systolic pressure (RVSP), the grade of right ventricular hypertrophy (RVH) and histological change showed no significant difference among rats receiving 20, 30 or 40 mg/kg Mct injection. Almost all rats given 10 mg or 20 mg/kg Mct survived through the experimental period of nine weeks. Rats given 10 mg per kg of Mct did not develop pulmonary hypertension or pathological abnormalities in the lungs. Rats receiving 20 mg/kg Mct showed transient elevation of RVSP, RVH and pulmonary histological changes in the early phase, but these findings regressed by the ninth week of the experiment. Namely, rats which received 20 mg pr kg of Mct revealed transient elevation of right ventricular systolic pressure, right ventricular hypertrophy and pulmonary histological changes only in the early phase and these changes regressed gradually thereafter. These results indicate some kind of transient and reversible factor may play a role in the development and regression of Mct-induced pulmonary hypertension in rats.

Animals↗