Biomedical subjects

T Katoh

Publications and source records attributed to T Katoh.

At least 415 records · Page 23Linked to original sources

PubMed1990

Diurnal rhythm in the plasma concentration of cortisol in paediatric patients with orthostatic dysregulation.

A gas chromatographic/mass spectrometric method using stable isotopically labelled cortisol as an internal standard was employed to determine patterns of episodic secretion of cortisol in three normal subjects and four paediatric patients with orthostatic dysregulation. The measurement of the plasma cortisol level at frequent time intervals revealed how the daily secretory pattern of cortisol differs in these patients and normal subjects.

Adolescent↗

PubMed1990

Effects of iron and desferrioxamine on Rhizopus infection.

To investigate the association among iron, desferrioxamine, and a Rhizopus infection, the influence of iron and/or desferrioxamine on experimental mucormycosis in mice was examined. All mice pretreated with iron, desferrioxamine, or a combination of iron and desferrioxamine died within 5 days after the inoculation of R. oryzae. In the mice fungal lesions were observed in the brain which resembled human cerebral mucormycosis. By contrast, the mortality in the control mice with R. oryzae was 20% through the 3-week experimental period. Therefore, it was demonstrated that iron as well as desferrioxamine administration markedly promotes the growth of R. oryzae. The increased susceptibility to R. oryzae was considered to be due to increased serum iron in the animals pretreated with iron only; however, pretreatment with desferrioxamine did not affect the amount of serum ion. Thus, the data suggest that desferrioxamine acts as a siderophore to R. oryzae and exerts an adverse effect on mucormycosis. This study has shown that the presence of iron and desferrioxamine enhances the virulence and pathogenicity of R. oryzae by serving as a growth factor.

Animals↗

PubMed1990

Isolations of dermatophyte from clinically normal scalps in M. canis infections using the hairbrush method.

The scalp hair of patients with dermatophytosis due to M. canis but without scalp lesions, and that of their family members without dermatophytosis were examined using the hairbrush method. The dermatophyte was detected in 93.8% of the scalps of those who lived in homes where cats were kept, and in 25% of those without cats. After the source of infection had been treated, the dermatophyte showed a gradually decreasing presence, finally disappearing altogether, so that no case of the disease on the scalp hair could be found. We inferred from the above findings in M. canis infections that, since the dermatophytes are seen in a high proportion of cases without scalp lesions, the dermatophytes, in many cases, exist only as saprophytes on the hair.

Adult↗

PubMed1990

Effect of combined dopamine and bunazosin on the ischemic heart after occlusion of the coronary artery.

In order to investigate whether dopamine combined with bunazosin improves cardiac function, the global and regional cardiac function and regional blood flow of 7 anesthetized dogs were analyzed before and after occlusion of the left anterior descending coronary artery (LAD), then after 10 micrograms/kg/min dopamine infusion following the LAD occlusion, and again after a bolus infusion of bunazosin 250 micrograms/kg. Dopamine with bunazosin reduced left atrial pressure from 4.9 +/- 0.9 to 3.1 +/- 0.5 mmHg (p less than 0.05) and improved cardiac output from 1.22 +/- 0.15 to 1.50 +/- 0.14 L/min (p less than 0.05), maximum positive left ventricular dp/dt from 1721 +/- 202 to 3600 +/- 663 mmHg/sec (p less than 0.05) and the time constant from 45.2 +/- 5.0 to 27.5 +/- 4.6 msec (p less than 0.01). Bunazosin added to the dopamine reduced the elevated left ventricular peak systolic pressure caused by dopamine from 130 +/- 7 to 113 +/- 8 mmHg (p less than 0.01). With regard to the regional wall motion, the impaired LAD-delta L (the segment systolic shortening) and LAD-Elmax (the slope of peak systolic pressure--endsystolic length relation) following the LAD occlusion improved from 0.5 +/- 2.5 per cent to 5.9 +/- 2.6 per cent (p less than 0.01) and from 50 +/- 9 to 82 +/- 14 mmHg/mm (p less than 0.01) after the infusion of dopamine with bunazosin. Dopamine greatly increased the Rate Pressure Product (RPP) from 12610 +/- 1120 after LAD occlusion to 16950 +/- 1420, whereas dopamine in combination with bunazosin did not increase the RPP due to a drop of LV-PSP with little change in regional myocardial blood flow. It was concluded that combining dopamine with bunazosin was useful for improving both the global and regional cardiac functions of the ischemic heart.

Adrenergic alpha-Antagonists↗

PubMed1990

Different responses of cytosolic and mitochondrial glutathione in rat livers after ethylene oxide exposure.

Acute effects of ethylene oxide (EO) at the concentration of 500 and 1500 ppm on glutathione and glutathione reductase of the cytosol and mitochondria in rat liver were examined. The levels of reduced glutathione content and the glutathione reductase activity in the cytosol at 1500 ppm exposure decreased to approximately 10% and 60% of those of control rats, respectively. The decreases in glutathione content and glutathione reductase activity in the mitochondria were less significant than those in the cytosol. Both mitochondrial NADPH-cytochrome c reductase and cytochrome c oxidase activities were only slightly affected by these EO exposures. These results indicate that the change in glutathione content in the cytosol mainly occurred due to the response to EO exposure, and that the mitochondrial glutathione did not serve for such cellular function.

Administration, Inhalation↗

PubMed1990

An ecological study on air pollution: changes in annual ring growth of the Japanese cedar and prevalence of respiratory symptoms in schoolchildren in Japanese rural districts.

The effect of air pollution caused by oil-fired electricity-generating stations on the annual ring growth of the Japanese cedar (Cryptomeria japonica, D. Don) and prevalence of respiratory symptoms in schoolchildren were investigated. By retrospective analysis the annual ring growth has been demonstrated to show good agreement with the general trend in air pollution. In addition it was found to be related to the prevalence of respiratory symptoms. The reduction in annual ring growth and increase in the prevalence of respiratory symptoms followed a deterioration in air pollution. Following upgrading of the power station and an improvement in air pollution, the annual ring growth and prevalence of respiratory symptoms showed opposite changes, respectively. Concerning the latter, the prevalence of wheezing and respiratory symptoms associated with school absence in schoolchildren with a positive skin test to house dust extract showed a closer correlation with the annual ring growth when compared with those who had never had a positive skin test.

Adolescent↗

PubMed1990

Glycogen accumulation in the renal tubular cells of spontaneously occurring diabetic WBN/Kob rats.

Cytoplasmic and nuclear accumulation of glycogen granules in the kidney cells of 72 male WBN/Kob rats with a long-term diabetic condition was studied histologically and by electron microscopy. The incidence and degree of the accumulation showed good correlation with the blood glucose concentration. In the kidneys, there was evidence of two types of lesion, cytoplasmic glycogen accumulation in the distal convoluted tubules and nuclear accumulation in the ascending thick segment of Henle's loops. Electron microscopically, the cytoplasmic glycogen accumulation was often associated with an increased number of lysosomal bodies containing lamellar bodies. Glycogen bodies, the halo of which was thought to be identical with that of nuclear bodies, were frequently observed in the nuclei containing the glycogen granules. These morphological and topographical differences between the two types of lesion were considered suggestive of different pathogenetic mechanisms for glycogen accumulation in the kidney cells.

Animals↗

PubMed1990

Direct effects of endothelin in the rat kidney.

In the present study, we tested the direct effects of endothelin (ET) on rat kidney in vivo. ET was infused into the left renal artery of anesthetized rats at a rate of 0.5, 5, 20, or 40 pmol/h. ET reduced ipsilateral urine volume (V), clearance of inulin (CIN), and clearance of p-aminohippuric acid (CPAH) in a dose-dependent manner. Thus ET at 20 pmol/h did not change V but decreased renal plasma flow (RPF) and glomerular filtration rate (GFR) by 27.6 +/- 14.3 and 30.8 +/- 10.4%, respectively, in the ipsilateral kidney. ET at 0.5 pmol/h was without effect and at 5 pmol/h had only minor effects on CIN and CPAH of ipsilateral kidney. At 40 pmol/h, ET reduced ipsilateral V, GFR, and RPF by 52.3 +/- 21.4, 58.4 +/- 14.5, and 72.5 +/- 10.6%, respectively. Filtration fraction and fractional excretion of Na remained unchanged during ET infusion. ET, 40 pmol/h, infused into the renal artery together with atrial natriuretic peptide (ANP) at a rate of 12 pmol/h reduced the ipsilateral V, GFR, and RPF by 33.2 +/- 6.3, 26.1 +/- 6.0, and 27.2 +/- 7.1%, respectively, decrements less than those with ET alone. When a calcium-channel blocker nicardipine was infused at a rate of 2.5 micrograms/h into the renal artery together with ET, 20 pmol/h, there was little change in the ipsilateral V, RPF, and GFR; ET, 40 pmol/h, with nicardipine did not change V and decreased GFR and RPF by 25.9 +/- 5.6 and 23.1 +/- 10.8%, respectively, decrements less than those without nicardipine.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1990

Remote afterloading transurethral radiotherapy for prostatic cancer.

We have developed a technique of transurethral radiotherapy for prostatic cancer using a remote after-loading system. The radioactive source is a cobalt-60 pellet with 3.7-Ci activity. Four patients with adenocarcinoma of the prostate were treated. In all patients, the local tumor response was rapid and satisfactory as judged by physical examination as well as ultrasonography. Serious complications were not seen. A new technique and preliminary clinical results are reported.

Adenocarcinoma↗

PubMed1990

[Evaluation of qualitative and quantitative tests for proteinuria and glucosuria as screening tests for cadmium-induced renal tubular dysfunction].

To evaluate the screening tests for cadmium-induced renal tubular dysfunction, qualitative and quantitative tests for urinary protein and glucose have been done in 146 urine samples obtained from subjects who had lived in the cadmium-polluted Jinzu River basin in Toyama Prefecture, Japan. The subjects consisted of 66 men and 80 women aged 55 to 71 years with beta 2-microglobulinuria exceeding 1,000 micrograms/g creatinine. The results obtained from this study were as follows; 1) The positive reaction (above 1+) for protein by the dipstick method was seen in 19.7% of men and 20.0% of women, and for glucose using Tes-tape in 48.5% of men and 33.8% of women. 2) The geometric means of protein and glucose concentrations in urine were 16.4 mg/dl and 12.7 mg/dl in men, and 14.2 mg/dl and 6.8 mg/dl in women, respectively. 3) The criteria of the primary screening in the health survey system for the residents in cadmium-contaminated areas conducted by the Japan Environment Agency were a proteinuria level exceeding 10 mg/dl and a glucosuria above (+/-) with Tes-tape. Nearly all subjects with urinary beta 2-microglobulin exceeding 30 mg/g creatinine were screened by these criteria in both sexes, whereas only 52.9% of men and 30.0% of women who had urinary beta 2-microglobulin between 10 to 30 mg/g creatinine could be screened in this manner. These results indicate that semiquantitative tests are insufficient as initial tests for screening cadmium-induced renal tubular dysfunction.

Cadmium Poisoning↗

PubMed1990

Superficial eosinophilic gastritis in laboratory beagle dogs attributable probably to diet.

Stomach tissues from 222 beagle dogs, which were used for toxicological studies, were examined histopathologically. Out of 190 dogs fed the same diet, 185 had gastric lesions, whereas all of 32 dogs fed another diet were free from them. The gastric lesions were noted as an accumulation of eosinophils, infiltration of inflammatory cells including lymphocytes, plasma cells and histiocytes in the gastric lamina propria, formation of foreign body type multinucleated giant cells, focal desquamation and papillary proliferation of mucosal epithelium. The lesions were confined to the superficial layer of the antral and pyloric mucosa, and neither desmoplasia nor clinical signs were seen. Multinucleated giant cells often contained amphophilic foreign bodies of varying appearance with inconsistent reaction for periodic acid-Schiff (PAS), but no definite causal agents were detected.

Animals↗

PubMed1990

Granular cell tumor of the tongue: an electron microscopical and immunohistochemical study.

Granular cell tumor of the tongue in a 29-year-old woman is reported including details of studies using electron microscopy and immunohistochemistry. Immunohistochemically, the tumor cells showed moderate positivity for S-100 protein. Electron microscopically, basal lamina, angulate bodies, myelin-like figures and axon-like structures were observed in the tumor. These findings may indicate that this tumor is a lesion of Schwann cell origin. The Japanese literature on oral granular cell tumor is also reviewed and discussed.

Adult↗

PubMed1990

Clinical experience with alumina ceramic transcutaneous connector to prevent skin-exit infection around CAPD catheter.

To prevent skin-exit infection, an important CAPD complication, we developed a transcutaneous connector made of Alumina ceramic. The new connector could be downsized, because an Alumina ceramic is characteristically bio-inert, rigid and non-porous. Our animal experiments with Alumina ceramic in soft tissue demonstrated the outstanding bio-compatibility of this material. The shape of the new transcutaneous connector was of simple cylindrical configuration so as to inhibit macrostress beneath the skin. To make contact with this connector in the body, a silicon tube was made into a Swan-necked catheter with a disk-shaped polyester cuff, which was positioned subcutaneously beneath the transcutaneous connector in order to reinforce adhesion to soft tissue. The silicon tube itself was L-shaped in its outside portion just before reaching the connector. We are now using this new transcutaneous connector made of Alumina ceramic on a CAPD catheter in 8 patients. In the longest case of a patient using it, there has been no skin-exit infection for 12 months. Also, there has been virtually no downgrowth phenomenon in the skin around the connector, and the connector and tissue have remained in very close contact, although fibrous connective tissue has been seen to form in the area.

Aluminum Oxide↗

PubMed1990

[A case of cystic metastatic intracranial amelanotic melanoma--analysis of findings in CT and MRI].

A case of cystic intracranial metastatic amelanotic melanoma is presented. As far as we know, cyst formation in intracranial melanoma is rare, and only 15 cases of intracranial amelanotic melanoma have been reported until now. A 63-year-old man was admitted with headache and progressive visual disturbance. CT scan revealed a large low-density mass with ring-like enhancement in the left frontal lobe. Both T 1-and T 2-weighted MRI images revealed hyperintensity. A left frontotemporal craniotomy was performed. A yellowish mass was observed in the frontal lobe. The content of the cyst consisted of old hematoma, xanthochromic fluid and necrotic tissue, was evacuated and the cyst wall was totally resected. No abnormal pigmentation was noted in the cyst wall and surrounding brain tissue. The histological examination revealed amelanotic melanoma. Primary lesion was found on the left thigh later and resected. The patient died of further intracranial metastasis with repeated hemorrhage 5 months after the admission. Both CT and MRI findings of our case is atypical as an intracranial malignant melanoma. However, these are compatible with those of intracerebral hemorrhage in subacute stage. It is suggested that melanoma may make the diagnosis difficult when tumor hemorrhage modifies the images of CT or MRI.

Brain Neoplasms↗

PubMed1990

[What plays an important role in the secretion of alpha-human atrial natriuretic polypeptide (alpha-hANP) during the early stage of acute myocardial infarction?].

To clarify the factors stimulating the secretion of alpha-human atrial natriuretic polypeptide (alpha-hANP) during the early stage of acute myocardial infarction (AMI), the plasma alpha-hANP level was sequentially measured and evaluated in terms of correlation with the severity of AMI, cardiovascular hemodynamics and endocrine functions in 61 patients with AMI. The plasma alpha-hANP levels within 24 hrs, from 48 to 72 hrs, and from 120 to 168 hrs after the onset of AMI were 213.8 +/- 198.0, 152.0 +/- 131.2, and 156.0 +/- 166.4 pg/ml, respectively, all of which were significantly higher compared to the control level (29.6 +/- 9.3 pg/ml). In surviving patients, the level of plasma alpha-hANP within 24 hrs was significantly higher than those in 48-72 and 120-168 hrs. On the contrary, non-surviving patients displayed prolonged elevation of alpha-hANP during the early stage of AMI. The initial alpha-hANP levels in Killip I, II, III and IV patients were 229.3 +/- 232.7 (n = 43), 216.7 +/- 86.6 (n = 7), 243.3 +/- 113.5 (n = 6) and 282.0 +/- 224.6 pg/ml (n = 5), respectively, and there were no significant differences between the categories.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1990

[Left ventricular aneurysmectomy after myocardial infarction--comparative study between true aneurysms and functional aneurysms].

Postinfarction left ventricular aneurysms are pathophysiologically divided into true, functional and false aneurysm. On 14 patients treated by aneurysmectomy, we studied the difference of pre- and post-operative cardiac function between true aneurysms (9 patients) and functional aneurysms (5 patients). The aneurysm area, which is expressed as the end-diastolic perimeter (akinetic or dyskinetic area/left ventricular silhouette), was 51.6 +/- 7.7% in the true aneurysms versus 35.7 +/- 6.0% in the functional aneurysms. Preoperatively, patients with a true aneurysm had a more severe clinical status than those with a functional aneurysm (Six of nine patients with a true aneurysm were in New York Heart Association functional class III or IV). Postoperatively, all patients except one with a true aneurysm and one with a functional aneurysm improved in clinical status. Nonaneurysmal EF, that is the function of the nonaneurysmal left ventricle, has a significant correlation to postoperative LVEF (r = 0.57, p less than 0.05). Nonaneurysmal EF was 54 +/- 4% in the true aneurysm group versus 51 +/- 16% in the functional aneurysm group. LVEF improved significantly (p less than 0.05) from 31 +/- 11% preoperatively to 55 +/- 10% postoperatively in the group of true aneurysm, but did not improved significantly from 43 +/- 12% to 50 +/- 9% in the functional aneurysm group. The postoperative akinetic area was 8.1 +/- 9.1% in the true aneurysm group versus 17.8 +/- 11.5% in the functional group. We conclude that larger and more adequate resection of aneurysms improves the cardiac function in the true aneurysm group more than in the functional aneurysm group.

Adult↗

PubMed1990

[Malignant pheochromocytoma presenting as an acute abdomen: a case report].

A case of right adrenal malignant pheochromocytoma was reported. The patient was a 16-year-old boy who complained of severe right side abdominal pain due to spontaneous hemorrhage into the retroperitoneal space. Right adrenalectomy was performed on Feb. 22, 1988 but the preoperative high serous catecholamine level did not drop to the normal level. Postoperatively bone and liver metastasis were detected by a 131I-MIBG scan. He was treated with a combination chemotherapeutic regimen consisting of cyclophosphamide, vincristine and dacarbazine in 2 repeated cycles but there was no effect. He died 5 months after the operation.

Abdomen, Acute↗

PubMed1990

[A successful removal of a left atrial massive ball thrombus caused by mitral stenosis].

A 66-year-old female with a mitral stenosis and a left atrial massive ball thrombus is presented. She was admitted due to a transient right hemiplegia and a speech disturbance. This thrombus had been detected preoperatively by an echocardiogram and a left atriography. A mitral valve replacement using a Björk-Shiley valve 27 mm, accompanied with the removal of the thrombus was performed. The ball thrombus was dark red, 55 x 35 x 32 mm in size and 15 g in weight. After the surgery, the patient progressed well. Because of the high frequency of peripheral embolism and of sudden death, a left atrial ball thrombus should be removed immediately.

Female↗