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Biomedical subjects

M Tamura

Publications and source records attributed to M Tamura.

At least 559 records · Page 31Linked to original sources
PubMed1993

Pleomorphic ventricular tachycardia arising from a new site during antiarrhythmic drug therapy.

UNLABELLED: We analyzed the site of VT origin and the induction mode of VT in 9 patients who showed new VT morphologies with different bundle branch block patterns after administering antiarrhythmic drug(s). In all patients, VT exhibiting the clinical morphology was induced in the drug free state. (1) VT origin: In 6 patients, VTs showing LBBB pattern had a site of origin at the right ventricular free wall, and VTs with RBBB pattern originated from the left ventricular free wall. VT from the intraventricular septum of the right ventricle showed RBBB pattern in two patients and VT with LBBB pattern arose from the posteroseptum of the left ventricle in one patient. (2) VTs with new morphologies: After administering drug(s), VTs with new morphologies were induced in 18 studies and the mean cycle length of these VTs was not different from that in the control study. Among them, the induction mode was less aggressive in 4 of 7 drug studies and more aggressive in 1 study. (3) VTs with the same morphology: VTs with morphologies identical to those of the clinical VTs were induced in 15 studies. However, the drugs' effect was evident. The mean cycle length of these VTs was significantly prolonged, and VTs were induced by less aggressive modes or at longer coupling intervals. IN CONCLUSION: (1) After administering drug(s), different electrophysiologic characteristics were observed between the VTs with new morphologies and the VTs with the same morphology. (2) If a new VT was induced by less aggressive modes after administering drug(s), the drug(s) might act to facilitate inducibility: proarrhythmic effect.

Adolescent↗
PubMed1993

Coronary perforation to the left ventricular cavity by a guide wire during coronary angioplasty.

We describe a case in which the guide wire penetrated through the left anterior descending artery into the left ventricular cavity during percutaneous transluminal coronary angioplasty. This complication of coronary angioplasty which had not been previously reported was suspected because of the characteristic motion of the guide wire on the X-ray image and was confirmed by echocardiography.

Angioplasty, Balloon, Coronary↗
PubMed1993

[Study on the relationship between appearance of autoantibodies and chest X-ray findings of asbestos plant employees].

Antinuclear factor (ANA) and rheumatoid factor (RF) were determined in 220 employees of an asbestos plant. The relationship of the appearance of the two factors to sex, age, smoking habit, duration of asbestos exposure and asbestos exposure level was studied. In 207 employees who had chest roentgenograms, the relationship of these two factors to pulmonary lesions and pleural lesions was examined. Of the 220 employees, 33 (15%) had ANA and 7 employees (3.2%) had RF. ANA positive rate in the asbestos plant employees was significantly higher than in the control. Factors significantly correlated to their appearance could not be demonstrated. With the progress of pulmonary lesions the ANA positive rate significantly elevated, but ANA positive rate was not significantly correlated with pleural lesions. RF did not show any significant correlation with any of the factors.

Adult↗
PubMed1993

Mortality and morbidity in two-year disease-free survivors of small cell lung cancer after treatment with combination chemotherapy with or without irradiation.

We evaluated the long-term outcome of 148 patients with small cell lung cancer (SCLC) who had been entered into clinical trials of chemotherapy with or without thoracic and prophylactic cranial irradiation (PCI) between 1981 and 1987. Eighteen patients (12%) survived for 2 or more years. With a minimum follow-up of 4.5 years, 10 of the 18 patients who remained disease-free at 2 years are currently alive and free of SCLC. Seven of these 10 patients currently function as they did before diagnosis. However, three suffer from central nervous system changes of varying degrees in severity which appeared 2-3 years after PCI. Eight of the 18 patients who were disease-free at 2 years have died. Two died of isolated relapse in the brain at 3.6 and 4.2 years after initiation of chemotherapy. Five died of other malignancies while continuing their complete response to SCLC; two of non-small cell lung cancer, two of acute myelogenous leukemia, and one of hepatocellular carcinoma. Another patient died of an unrelated disease without any evidence of SCLC. A small but substantial proportion of patients who underwent intensive treatment will achieve long-term survival; however, these patients remain at higher risk for second cancers and late toxicities. Therefore, attention must be directed to defining the safest way to employ such treatment in the management of SCLC.

Adult↗
PubMed1993

Small gliomas: clinicopathological study.

The clinicopathological characteristics of small gliomas were investigated in nine patients with gliomas less than 2 cm in diameter. The tumor histology and proliferative activity were also examined. Three tumors occurred in the white matter and six at the corticomedullary junction. Histological diagnosis, Daumas-Duport's grading, bromodeoxyuridine labeling index, and proliferating cell nuclear antigen counts were well correlated. Most small gliomas were histologically benign, localized, and removable if not in eloquent areas of the brain. However, some cases showed high-grade glioma and invasive character at the early stage, resulting in a poor outcome.

Adolescent↗
PubMed1993

Pathological anatomy of autopsy brain with malignant glioma.

The morphology of supratentorial malignant glioma was examined in autopsy brains from three anaplastic astrocytoma and 11 glioblastoma multiforme patients. Large histological preparations and routine preparations were used to investigate the primary lesion site, infiltration to adjacent brain, and cerebrospinal fluid (CSF) dissemination. The primary lesion sites showed active tumor growth with mass effect in three cases, necrotic tumor and brain with no or mild mass effect in nine, and no residual tumor in two. Tumor infiltration included extensive bilateral cerebral hemisphere infiltration in seven cases, moderate infiltration of one or two lobes in three, minimal infiltration just beyond the tumor bed in two, and no infiltration in two. Infiltration occurred along the fiber tract and subependymal tissue. CSF tumor cell dissemination occurred in the ventricular system in two cases, cerebral subarachnoid space in five, and spinal subarachnoid space in one. Small fibrillated cells and small anaplastic cells predominated in infiltrated lesions and CSF dissemination.

Adult↗
PubMed1993

[Transition of diagnosis and treatment for impotence].

Statistic study was made on 685 outpatients with erectile dysfunction during 13 years periods from 1979 to 1991 in the Department of Urology, Takamatsu Red Cross Hospital. The age distribution showed the highest frequency in the thirties decade (27.9%). 1. Diagnosis Nocturnal penile tumescence monitoring was the only method to distinguish organic impotence from functional impotence during the first 5 years. From 1984 we have been able to diagnose corporal veno-occlusive insufficiency (CVI) by papaverine test and dynamic infusion cavernosometry and cavernosography. Measurement of penile brachial index and pelvic angiography were performed to diagnose arterial insufficiency (AI). In neurological examination we have measured bulbo-cavernosus reflex latency and nerve conduction velocity of the dorsal penile nerve and performed microvibration measurement and sweat spots test. All diagnostic methods were established in 1987 and we have been able to classify about 80% patients. We classified 305 patients during the last 5 years from 1987 as follows: psychogenic; 31.1%, CVI; 20.0%, AI; 7.9%, neurogenic; 7.9%, others; 14.1%, drop-out and unknown; 19.0%. 2. Treatment In the beginning only counseling and drug therapy were performed. However we lately performed various suitable methods for individuals based on their diagnoses. We performed counseling, drug therapy and intracavernous injection of vasoactive drug therapy for recovery of spontaneous erection (vascular training) for psychogenic IMP. The efficacy rate of counseling was low (30.4%) but that of drug therapy was 41.6%, and that of vascular training, 64.2%. For CVI without other factors we performed venous surgeries. Only about 25% of them perform sexual intercourse with or without self injection of vasoactive drug (self injection).(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1993

[The relaxation of human corpus cavernosum caused by nitric oxide].

Non-adrenergic non-cholinergic nerves (NANC) are thought to be important in the relaxation of corpus cavernosum for erectile function. On the other hand, it has been shown that nitric oxide (NO) is synthesized from L-arginine and released by the endothelium of blood vessels and accounts for the activity of endothelium-derived relaxing factor (EDRF). We studied whether electrical field stimulation (EFS) of isolated strips of human corpus cavernosum released NO and whether it could act as a NANC neurotransmitter. Human penile tissue specimens were mounted in an organ bath and the isometric tension recorded. EFS was applied to precontracted strips between two parallel platinum electrodes. Relaxation induced by EFS was not influenced by guanethidine or atropine, but was markedly inhibited by NG-nitro-L-arginine which is an analog of L-arginine that inhibits the conversion of L-arginine to NO, and hemoglobin which is an agent that inhibits the biological actions of NO. Methylene blue which is an inhibitor of cytosolic guanylate cyclase also reduced the relaxation of EFS, but not completely. The inhibitory effect of NG-nitro-L-arginine was reversed by addition of excess L-arginine. Exogenous NO relaxed human corpus cavernosum. The relaxation was only a transient response and concentration-dependent. The profile of responses is similar to that evoked by EFS. Our data clearly demonstrate the release of NO during EFS and the function of NO as a NANC neurotransmitter. Human penile erection may be mediated by NO generated in response to NANC neurotransmission.

Adult↗
PubMed1993

[Postoperative results of ligation of crura penis for impotence with corporal veno-occlusive insufficiency].

We performed ligation of the crura penis for 34 impotents with corporal veno-occlusive insufficiency without arterial insufficiency and neural dysfunction from October 1987 to April 1991. Ages ranged from 24 to 72 (52.6 +/- 12.7) years old and follow up period was from 1 to 41 (17.7 +/- 12.6) months. For six patients ligation of the crura only was performed, for 22 ligation of the crura and deep dorsal vein (DDV) as well was performed at the same time, and for 6 crural ligation was performed after ligation of DDV. These operations required less than one hour and there were no severe complications. The postoperative results at 1 month were as follows: Excellent (sufficient spontaneous erection was recovered); 18, Improved (complete erection with intracavernous papaverine injection was achieved); 13, and Failure; 3. Erectile function was maintained only in 50% of the 18 pts. graded excellent. Ninety percent of the 31 patients graded either excellent or improved could maintain erectile function after 40 months with papaverine injection. Venous surgeries could not be a primary treatment for correcting the outflow abnormalities (of the veins). So it is conceivable that failure or recurrence could occur during a long follow up period. We concluded that crural ligation was acceptable as the first line treatment for erectile dysfunction due to corporal veno-occlusive insufficiency because of its relative non-invasiveness compared to other venous surgeries.

Adult↗
PubMed1993

A novel endogenous sodium-pump inhibitor in pig urine: purification and comparison with the inhibitor purified from bovine adrenal glands.

To clarify the chemical nature and pathophysiological significance of an endogenous, specific Na-pump inhibitor, extracts of various tissues have been examined. The activities were extracted by an Amberlite XAD-2 adsorbent and fractionated by high-performance liquid chromatography (HPLC) on an ODS column. Among many tissues and fractions tested, the extract of pig urine has been found to contain a large amount of 86Rb uptake inhibitory activities. The strongest inhibitory activity for 86Rb influx into erythrocytes also exhibited a cross-reactivity with anti-ouabain antibodies. This activity has been purified to homogeneity using five steps of reverse-phase HPLC. Although most of the dose-response curves for this purified Na-pump inhibitor, designated as uroxin, in the various assay systems paralleled those of ouabain and the inhibitor purified from bovine adrenal glands (designated as adrexin C), the cross-reactivity curve with anti-ouabain antibodies did not. The retention time of uroxin on an ODS HPLC column was also different from that of digoxin, ouabain, or adrexin C. 1H nuclear magnetic resonance spectroscopic study suggests that uroxin is a novel Na-pump inhibitor that is structurally different from any of the known cardiotonic steroids or the substances previously reported to exhibit Na-pump inhibitory activity. Thus, uroxin may be a new type of endogenous regulator for the Na pump.

Adrenal Glands↗
PubMed1993

[Sarcoidosis].

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Adolescent↗
PubMed1993

[Possible existence of non-identified anti-leukemic factor in the crude sampling of natural human interferon gamma].

Human natural interferon gamma (IFN-gamma) exerts differentiating and cytocidal effects in vitro on the human myeloblastic leukemia cell line ML-2. The anti-leukemic effects of the crude preparation of IFN-gamma are more intensive than those of the mixture of purified IFN-gamma, IFN-alpha, tumor necrosis factor alpha and lipopolysaccharide, suggesting existence of an unknown anti-leukemic factor in the crude IFN-gamma sample.

Humans↗
PubMed1993

[Causes of idiopathic interstitial pneumonia (IIP): inhaled dust as environmental problem].

We have reported that patients with IIP can be roentgenologically grouped into two subtypes, typical (type-A) and atypical (type-B). The characteristic feature of X-ray findings in type-A is marked restriction of the lung, especially of the lower lobes, and in type-B is emphysematous changes in addition to the findings of type-A. In this study, to clarify the pathological findings of these two subtypes, 60 IIP patients in whom open lung biopsy and/or autopsy were performed were studied both clinically and pathologically. The following results were obtained. 1) Pathological features of type-A were alveolitis, marked restriction of the lung secondary to atelectasis and fibrosis of lung parenchyma, and honeycombing as a result of remodeling. 2) The features of type-B were intra-alveolar organization and secondary emphysema after intra-alveolar inflammation (pneumonia) overlapped the pathological changes of type-A. 3) Patients with a history of dust inhalation were much more frequently observed in type-B than in type-A (p < 0.01). These results suggest that inhaled dust may be a causative factor of IIP, especially of type-B.

Dust↗
PubMed1993

[Chronic type hypersensitivity pneumonitis].

The clinical features and chest X-ray appearances of chronic type hypersensitivity pneumonitis closely resemble those of idiopathic interstitial pneumonia. Therefore, it is very difficult to make a correct diagnosis without detailed information. Our study showed that bronchoalveolar lavage and lung biopsy are useful examinations for the differential diagnosis of these two diseases. The characteristic finding of bronchoalveolar lavage of chronic type hypersensitivity pneumonitis is still lymphocytosis, as is also seen in the acute type. The pathological findings of chronic type hypersensitivity pneumonitis are alveolitis with marked lymphocyte infiltrations and granuloma formation although the number of granulomas is low. Recently, we experienced five patients with chronic type farmer's lung. The average age of these five patients was significantly older than that of acute type farmer's lung. They had engaged in farming after the onset of their disease, which suggested continuous chronic exposure to mouldy hay. It is concluded that patients with hypersensitivity pneumonitis, especially aged people, should avoid antigen exposure and should be followed up the progress of the disease with intensive care.

Chronic Disease↗
PubMed1993

Torsades de pointes associated with acquired long QT syndrome: observation of 7 cases.

We examined the clinical characteristics and electrocardiographic findings of 7 patients having the acquired long QT syndrome who developed torsades de pointes while receiving no antiarrhythmic drugs. A total of 43 episodes of torsades de pointes were documented among these patients. Underlying heart diseases were present in 6 patients and hypopotassemia (< or = 3.3 mEq/l) in 4. Four had bradycardia (< or = 52 beats/min) immediately before the development of torsades de pointes. The QTc intervals measured immediately before the episodes of torsades de pointes were significantly longer than those 6-24 hours before the episodes (0.69 +/- 0.10 vs 0.56 +/- 0.10 sec, p < 0.05), while heart rates did not differ significantly between these 2 periods (54 +/- 12 vs 58 +/- 15 beats/min). The ventricular rate of torsades de pointes was 192 +/- 24 beats/min. A "long-short initiating cycle" was noted in all 43 episodes, and the initiating premature ventricular beat (PVB) showed the "R on T(U)" phenomenon in 42 of the episodes. A notched T-U complex due to a prominent slow wave (U wave) at the end of the T wave was noted in 5 patients immediately before the episodes of torsades de pointes. Prolongation of the preceding RR interval was directly related to the increase of the U wave amplitude, which caused an increased likelihood of the occurrence of PVBs near the peak of the U wave. Torsades de pointes developed from the largest U wave. Direct current cardioversion was transiently effective for treating torsades de pointes, and intravenous lidocaine, atropine and verapamil were effective in some cases.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1993

[Effects of the volume of the reservoir bag and the amount of fresh gas flow on FRC during CPAP].

We have examined effects of the volume of the reservoir bag and the amount of fresh gas flow (FGF) on FRC during CPAP with PEEP level of 8 or 11 cmH2O. We used reservoir bags of 4 different volumes (5, 10, 15, 20l). We set up the air way pressure graduation between inspiration and expiration (delta P) by adjusting FGF rate, then we measured delta FRC and other respiratory parameters in 8 volunteers (26.3 +/- 0.8 yo). With the same PEEP level, delta P decreased but FRC increased by increasing FGF rate. When we used a lager reservoir bag, FGF rates which are necessary to set up the minimum delta P decreased during CPAP. We could obtain a larger delta FRC by using a larger reservoir bag compare with a smaller one, at the same delta P using same CPAP level. We should consider not only delta P but also the volume of the reservoir bag to obtain a reasonable and comfortable CPAP.

Adult↗
PubMed1993

Clinical evaluation of thallium-201 SPECT in supratentorial gliomas: relationship to histologic grade, prognosis and proliferative activities.

We performed 201Tl SPECT and cell kinetic studies on 28 presurgical patients with supratentorial gliomas by administering bromodeoxyuridine (BUdR). All patients had surgery and had follow-up for more than 25 mo. In patients with grade IV glioma (198.1% +/- 32.8%, n = 10), the 201Tl index, expressed as the count rate of the tumor site to the count rate over the contralateral normal region, was significantly higher than that in patients with grade III glioma (140.5% +/- 15.1%, n = 4, p < 0.01) or low-grade glioma (104.1% +/- 22.6%, n = 14, p < 0.001). A significant correlation was observed between the 201Tl index and BUdR-positive cells in excised tumor specimens (r = 0.67, p < 0.001). The 201Tl index of the 12 patients who died was higher than those who survived (173.2% versus 122.4%, p < 0.01). These results show the clinical utility of 201Tl brain SPECT in imaging supratentorial glioma and that the 201Tl index is representative of proliferative activity of the tumor.

Adult↗