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T Kanazawa

Publications and source records attributed to T Kanazawa.

At least 181 records · Page 10Linked to original sources
PubMed1989

[A case of the benign adrenal adenoma with remarkably high concentrations of deoxycorticosterone and 11-deoxycortisol].

The case was a 33-year-old woman with hypertension and hypokalemia, who presented depression of renin activity and the abnormal elevation of plasma deoxycorticosterone (DOC) and 11-deoxycortisol on laboratory tests. After admission, abdominal CT scan, 131I-adosterol scintigram and adrenal venogram revealed a tumor in the left adrenal, which histologically seemed to be benign. When the tumor was resected, blood pressure and all the biochemical data returned to normal range. DOC and 11-deoxycortisol levels in the tumor were abnormally elevated as compared with those in the normal adrenal tissue. These findings suggested that the abnormal elevation of hormone levels resulted from depression of 11 beta-hydroxylase. Though numerous adrenal tumors have been documented, we rarely encounter an apparently benign adrenal tumor that produces 2 kinds of hormones. This seemed to be the first case of benign adrenal tumor in which both DOC and 11-deoxycortisol were elevated.

17-Hydroxycorticosteroids↗
PubMed1989

[Evaluation of masticatory efficiency and the analysis of occlusal pattern factors using computer image processing method].

The purpose of this study was to evaluate the newly developed computer-assisted image processing method. We applied this method for the evaluation of masticatory efficiency and the analysis of occlusal pattern factors: the number and the size of occlusal contact areas, the number of and the size of the projected facets. We compared this new method with our conventional one which is the simplified particle counting method using a sieve and measuring the occlusal pattern factors with a planimeter. The results were as follows: 1. It is possible to count the number of particles within an optional range of size with the new method. 2. The new method may be used with minimum error for the measurement of occlusal pattern factors. We believe that this newly developed computer-assisted image processing method can be put to practical use for clinical evaluation of masticatory efficiency and analysis of occlusal pattern factors.

Dental Occlusion↗
PubMed1989

[Survey on oral and maxillofacial injuries in contact sports and diffusion of mouthguards].

Recent reports have shown an increase of oral and maxillofacial injuries caused by sports activities. In European and American countries, mouthguards are the popular measure against these injuries. The purpose of this study was to survey the rate of incidence of oral and maxillofacial injuries caused by contact sports, the diffusion and the evaluation of mouthguards and the interest in mouthguards in Japan. Questionnaires were sent to 244 Rugby football teams in Aichi prefecture and 27 American football teams in the Tokai area. We received replies from 153 Rugby football teams and 17 American football teams, and the results were as follows: 1) The rate of incidence of oral and maxillofacial injuries was 239 players out of 4721 players, which means 5.1% in Rugby football and 22 players out of 428 players, which means 5.1% in American football. 2) The diffusion of mouthguards was 20 out of 153 teams in Rugby football and 16 out of 17 teams in American football. And most of them are using commercially available mouthguards. 3) Almost all teams were not satisfied with their mouthguards and complained of speaking difficulties, discomfort and easy dislocation. 4) Almost all teams desire the improvement of mouthguards. 5) Teams with no experience of mouthguards were very much interested in the use of mouthguards but they do not have enough information about mouthguards. 6) We have to enlighten players and their instructors about mouthguards and diffuse the use of mouthguards more positively to contact sports players.

Adolescent↗
PubMed1989

[Two resected cases of human pulmonary dirofilariasis].

Two patients with human pulmonary dirofilariasis are presented. A 58-year-old woman in Tokyo (Case 1) was pointed out to have a nodular shadow in the right lower field on a routine chest X-ray in 1983. At thoracotomy a 2 cm nodule in the right lower lobe was removed by wedge resection. The nodule was a granuloma containing an immature Dirofilaria species. A 49-year-old man living in Chiba Prefecture (Case 2) was found to have a nodular shadow in the right lower lobe on a chest X-ray in 1987. He was asymptomatic, but laboratory values showed a WBC count of 5,800 with 17% eosinophils. Wedge resection of the lesion was carried out and it was found to be a 2 cm granuloma containing an immature Dirofilaria immitis. The dog heartworm, D. immitis, can occasionally cause pulmonary granulomas in man. More than 50 cases have been reported in Japan, but most of them were diagnosed by postoperative histopathologic examination. Although immunoserological examination or medical treatment were attempted in some cases, they are not established at present. The important thing is that pulmonary dirofilariasis should be included in the differential diagnoses of nodular lesion of the lung.

Diagnosis, Differential↗
PubMed1988

Conformational changes in the vicinity of the N-iodoacetyl-N'-(5-sulfo-1-naphthyl)ethylenediamine attached to the specific thiol of sarcoplasmic reticulum Ca2+-ATPase throughout the catalytic cycle.

In the previous experiment (Suzuki, H., Obara, M., Kuwayama, H., and Kanazawa, T. (1987) J. Biol. Chem. 262, 15448-15456), the Ca2+-ATPase of sarcoplasmic reticulum vesicles was labeled with N-iodoacetyl-N'-(5-sulfo-1-naphthyl)ethylenediamine without a loss of the catalytic activity. The main labeled site was Cys674. A large monophasic fluorescence drop occurred upon ATP binding to the catalytic site of the Ca2+-activated enzyme in the presence of K+. The present results show that this fluorescence drop is biphasic in the absence of K+. The first and rapid phase of this drop accounts for most of the fluorescence drop. This phase reflects a conformational change in the enzyme.ATP complex. The second and slow phase, being much smaller than the first phase, coincides with phosphoenzyme (EP) isomerization from the ADP-sensitive form to the ADP-insensitive form. This phase disappears when accumulation of ADP-insensitive EP is inhibited by K+ or when EP isomerization is prevented by the N-ethylmaleimide treatment. These results show that this phase reflects a conformational change upon EP isomerization. When free Ca2+ is chelated after EP formation from ATP, the fluorescence intensity is restored to the initial level without Ca2+. This restoration coincides with EP decomposition. This suggests that the fluorescence restoration reflects a conformational change upon hydrolysis of ADP-insensitive EP. This probability is supported by the concurrent occurrence of the Pi-induced fluorescence drop and EP formation from Pi. The results demonstrate that the fluorescence drop upon ATP binding is predominant in the fluorescence change throughout the catalytic cycle.

Adenosine Triphosphate↗
PubMed1988

Selective inhibition by ionophore A23187 of the enzyme isomerization in the catalytic cycle of Na+, K+ -ATPase.

The effect of an ionophore A23187 on the purified Na+,K+-ATPase from the outer medulla of pig kidney was investigated. When the enzyme was pretreated with A23187 in the presence of Na+ and K+, the ATPase activity was inhibited almost completely. When the pretreatment was performed in the presence of Na+ and absence of K+, formation of the phosphoenzyme (EP) from ATP was only slightly retarded. The steady state level of EP thus formed was not altered, but EP decomposition was strongly inhibited. Under these conditions, the accumulated EP was sensitive to ADP and insensitive to K+. On the other hand, when the pretreatment was performed in the absence of Na+ and presence of K+, EP formation following simultaneous addition of Na+ and ATP was extremely slow, but the steady state level of EP was not substantially altered. When the pretreatment was performed in the absence of Na+ and presence of K+, EP formation from Pi was unaffected, and the EP formed was in rapid equilibrium with Pi of the medium. These results demonstrate that A23187 selectively inhibits isomerization of the enzyme between the high Na+ and low K+ affinity form and the low Na+ and high K+ affinity form in the catalytic cycle, whether or not the enzyme is phosphorylated. This inhibition is quite similar to the A23187-induced inhibition of the enzyme isomerization in the catalytic cycle of the Ca2+ -ATPase from sarcoplasmic reticulum (Hara, H., and Kanazawa, T. (1986)J. Biol. Chem.261, 16584-16590). These findings suggest that some common mechanism, which is involved in the enzyme isomerization, between these two transport ATPases is strongly disturbed by A23187.

Adenosine Diphosphate↗
PubMed1988

Effects of KB-2796, a new calcium antagonist, and other diphenylpiperazines on [3H]nitrendipine binding.

The effect of KB-2796, a new diphenylpiperazine calcium antagonist, on [3H]nitrendipine ([3H]NTD) binding was investigated in synaptosomal membranes prepared from the guinea pig cerebral cortex. KB-2796 inhibited [3H]NTD binding in a dose-dependent manner with an IC50 value of 86 nM. In this respect, KB-2796 was the most potent among the diphenylpiperazine derivatives tested. Saturation binding data indicated that this inhibition resulted from a decrease in the binding affinity without changes in the maximal number of binding sites. KB-2796, however, significantly increased the dissociation rate constant of [3H]NTD from radiolabeled membranes. This finding suggests that KB-2796 inhibits [3H]NTD binding by a negative heterotropic allosteric mechanism. Other diphenylpiperazines tested also showed similar inhibitory properties. Diphenylpiperazines may act at a site, which is different from the 1,4-dihydropyridine binding site, on the voltage-dependent calcium channel.

Animals↗
PubMed1988

Disseminated intravascular coagulation accompanying thoracic and abdominal aortic aneurysm; report of three cases.

We reported three patients who developed disseminated intravascular coagulation (DIC) accompanying thoracic and abdominal aortic aneurysm. The first case, a 26-year-old man with dissecting aortic aneurysm developed DIC with clinical bleeding after operating on glaucoma. The administration of fibrinogen concentrates and antifibrinolytic agent made his DIC improve. The second case, a 70-year-old man with abdominal aortic aneurysm developed DIC showing large ecchymosis after angiography. His DIC disappeared after operation on aneurysm. The third case, a 73-year-old woman with thoracic and abdominal aneurysm developed laboratory-DIC without severe hemorrhagic diathesis. During antifibrinolytic therapy, platelet count, fibrinogen and fibrinogen degradation product (FDP) level improved. Since the treatment of the coagulopathy might be varied in the situation of the cause and clinical course, it is noted that anti-fibrinolytic therapy was effective in our two cases.

Adult↗
PubMed1988

Epidemiologic studies on schistosomiasis japonica in a newly found habitat of Oncomelania snails in Japan.

Epidemiologic studies' on schistosomiasis japonica were carried out in the Obitsu River basin of central Boso Peninsula, a newly found habitat of Oncomelania snails in Japan. Forty-five (4.1%) of 1,102 schoolchildren and 64 (10.4%) of 618 junior high school students were positive for the skin test with veronal buffered saline-extracted Schistosoma japonicum antigen. None was positive by the enzyme-linked immunosorbent assay, complement fixation test, double diffusion test in agar, and circumoval precipitin test. About one fifth of 356 adult inhabitants showed positive reactions in the enzyme-linked immunosorbent assay and complement fixation test as well as in the skin test, although only 25 individuals (7%) were positive for the circumoval precipitin test. All of 70 individuals who had shown positive reactions in at least two of the immunological tests were negative for a series of 5 stool examinations with the AMS III method. Release of S.japonicum cercariae was not observed in 15,000 O. hupensis nosophora collected in this area. Repeated examinations by dipping mice into irrigation ditches were negative. These observations, with the fact that all of 15 patients reported from nearby hospitals to have schistosome eggs in their tissues were over 45 years old, suggest that schistosomiasis has become a disease of the past in this area.

Adolescent↗
PubMed1988

General pharmacology of 1-(2-ethoxyethyl)-2-(4-methyl-1-homopiperazinyl)benzimidazole difumarate. 2nd communication: Effects on the circulation and the other systems.

Effects of 1-(2-ethoxyethyl)-2(4-methyl-1-homopiperazinyl)benzimidazole difumarate (KB-2413) on the circulation and the other systems were compared with those of ketotifen and chlorpheniramine. 1. Among the effects on the circulation and the respiratory system, KB-2413 as well as ketotifen and chlorpheniramine transiently inhibited respiration at 3 mg/kg i.v. and slightly decreased blood pressure in dogs. KB-2413 slightly decreased heart rate in dogs, but ketotifen slightly increased it. 2. KB-2413 at 100 mg/kg p.o. slightly decreased the volume of gastric juice in rats and dose-dependently increased biliary secretion in rats in the dose range of 10-100 mg/kg i.d. On the other hand, ketotifen and chlorpheniramine decreased biliary secretion. 3. KB-2413 inhibited the spontaneous movements of various isolated smooth muscles at a high concentration of 10(-4) g/ml. 4. The autonomic system in cats and the motor nervous system in rats were not influenced by KB-2413 at 3 mg/kg i.v. 5. The blood clotting system, blood sugar level, urine volume and urinary electrolytes in rats were not affected by KB-2413 in the dose range of 10-100 mg/kg p.o. 6. KB-2413 inhibited carrageenin-induced rat paw edema at 100 mg/kg p.o. In conclusion, KB-2413 showed a less potent effect on the circulation and the other systems than ketotifen and chlorpheniramine, and no results suggested serious side effects of KB-2413.

Animals↗
PubMed1988

[Pharmacokinetic study on oxalate in rats].

The pharmacokinetics of oxalate were studied in normal and nephrectomized rats, using radioisotope-labelled oxalate to resolve the mechanism of calcium oxalate stone formation. Plasma disappearance of 14C-oxalate was analyzed with a 2-compartment open model, and each compartment volume, the first-order rate constant for elimination, and the first-order rate constant for transfer between the central compartment and peripheral compartment were obtained. These values were compared with those for inulin. In normal rats, the total distribution volume was 57% of body weight for oxalate and 34% for inulin. The elimination rate constant from the central compartment for oxalate was lower than that for inulin, but oxalate had a much larger central compartment volume than inulin. Thus, the total clearance of oxalate was greater than that of inulin. In nephrectomized rats, total clearance of oxalate decreased to 1/6 of that in normal rats, while total clearance of inulin decreased to 1/27 of that in normal rats. These results suggest that oxalate is more diffusible than inulin, and that oxalate is excreted mainly from the kidney.

Animals↗
PubMed1988

[A case of stone former with pacemaker treated by extracorporeal shock wave lithotripsy].

A stone former, a 60-year-old male with a pacemaker, was treated by extracorporeal shock wave lithotripsy (ESWL). He had been on a DVI pacemaker due to sick sinus syndrome since the age of 52. During treatment for left ureteral stone by ESWL, the pacemaker was stopped, since there was a possibility of extra systoles caused by coupled triggering of the shock wave with the pacemaker spike wave in ECG. Pulse and blood pressure were maintained by continuous drip infusion of phenylephrine chloride and isoproterenol. As a result, ESWL was accomplished and pacemaking was reestablished without any problem. KUB revealed that the patient became stone free on the postoperative 17th day.

Electrocardiography↗
PubMed1988

[A case of bronchial carcinoma showing regression upon intratumoral administration of OK-432].

A 38-year-old female suffering from chronic respiratory symptoms due to lung cancer occupying the left main bronchus was treated by frequent intratumoral injections of OK-432. The immune-modifying therapy was performed as follows; 0.2 KE of OK-432 was injected intracutaneously once a week, then the dose was gradually increased to 3.0 KE once a week. Following immunization, intratumoral injection was done under endoscopy at a dose of 3.0 KE every two weeks. Three months later, the tumor showed remarkable regression, and clinical symptoms were diminished. In conclusion, intratumoral injection of OK-432 was considered to be very beneficial in lung cancer.

Adult↗
PubMed1987

A conformational change of N-iodoacetyl-N'-(5-sulfo-1-naphthyl)ethylenediamine-labeled sarcoplasmic reticulum Ca2+-ATPase upon ATP binding to the catalytic site.

Sarcoplasmic reticulum vesicles were modified with a fluorescent thiol reagent, N-iodoacetyl-N'-(5-sulfo-1-naphthyl)ethylenediamine. One mol of readily reactive thiols per mol of the Ca2+-ATPase was labeled without a loss of the catalytic activity. The fluorescence of the label increased by 8% upon binding of Ca2+ to the high affinity sites of the enzyme. This fluorescence enhancement probably reflects a conformational change responsible for Ca2+-induced enzyme activation. Upon addition of ATP to the Ca2+-activated enzyme, the fluorescence decreased by 15%. This fluorescence drop and formation of the phosphoenzyme intermediate were determined under the same conditions with a stopped-flow apparatus and a rapid quenching system. The amplitude of the fluorescence drop thus determined was saturated with 3 microM ATP. This shows that the fluorescence drop was caused by ATP binding to the catalytic site. In contrast, the rate of the fluorescence drop was not saturated even with 50 microM ATP. The fluorescence drop coincided with phosphoenzyme formation at 0.5 or 3 microM ATP, but it became much faster than phosphoenzyme formation when the ATP concentration was raised to 100 microM. These results indicate that the ATP-induced fluorescence drop reflects a conformational change in the enzyme.ATP complex. The fluorescence drop was accompanied by a red spectrum shift, which suggests that the label was exposed to a more hydrophilic environment. The electrophoretic analysis of the tryptic digest of the labeled enzyme (10.9 kDa) showed that almost all of the label was located on the 5.2-kDa fragment which includes the carboxyl terminus and the putative ATP-binding domain. The sequencing of the two major labeled peptides, which were isolated from the thermolytic digest of the labeled enzyme, revealed that the labeled site in either of these peptides was Cys674. It seems likely that the label bound to this Cys674 could be involved in the observed fluorescence changes.

Adenosine Triphosphate↗