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Biomedical subjects

A Hashimoto

Publications and source records attributed to A Hashimoto.

At least 55 records · Page 3Linked to original sources

[Orthotopic heart transplantation with sinus venosus incision of right atrium in dogs--preservation of sinus node and original right atrium].

Orthotopic heart transplantation with sinus venosus incision of right atrium was aimed to preserve the sinus node, terminal crista, sinus node artery and whole right atrial muscle of the transplanted heart. This transplant procedure was performed in eight mongrel dogs and electrocardiogram was followed up to five postoperative months. Direct cross circulation technique was employed as an alternative of cardiopulmonary bypass. Donors and recipients were 6 to 8 kg mongrel puppies, and 19 to 25 kg adult dogs supported the cross circulation. Myocardial protection of the donor heart was carried out by low-flow continuous potassium cardioplegia and topical cooling. Right atrial incision of the donor heart was made longitudinally in the posterior wall of sinus venosus. After a median sternotomy, ascending aorta and superior and inferior venae cavae of the recipient were cannulated and connected respectively with carotid artery and jugular vein of the cardiopulmonary support dog. Electrocardiogram, arterial pressure and central venous pressure of the recipient were monitored, and an electro-magnetic flow meter was employed for measuring the blood flow of direct cross circulation. The native heart was resected after aortic cross-clamping, and left atrium and atrial septum were sutured continuously. Sinus venosus incision of the donor heart was anastomosed to the recipient's right atrium. Ascending aorta and pulmonary trunk were reconstructed in the standard fashion. Aortic cross-clamp time was less than one hour and sinus rhythm of the transplanted heart was continued in all cases. Five of the eight dogs were alive postoperatively for one week to five months.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals

[Para-esophageal anastomosis of left atrium in orthotopic heart transplantation in dogs: possibility for electrophysiologic examination of the transplanted heart with transesophageal atrial stimulation].

Para-esophageal anastomosis of left atrium was examined in orthotopic heart transplantation as a new surgical technique for transesophageal electrophysiologic study of the transplanted heart. Seven orthotopic heart transplantations were performed in mongrel dogs. Left atrial appendage of the donor heart was trimmed as a flap and the sinus venosus of right atrium was incised posteriorly. An upper midline incision was made in the posterior wall of left atrium of the recipient after native ventricles were resected. Left atrial appendage flap of the donor heart was anastomosed to the posterior incision of native left atrium, and the remains of left atrium were sutured continuously. Sinus venosus incision of the donor heart was anastomosed to the right atrium of recipient. Ascending aorta and pulmonary trunk were reconstructed in the standard fashion. Transesophageal atrial pacing was possible during and after weaning from cardiopulmonary bypass in all seven cases. The appendage flap was found to occupy one third of the posterior wall of left atrium at the time of sacrifice. It was suggested that para-esophageal anastomosis of left atrium would be an useful technique for transesophageal electrophysiologic study of the transplanted heart.

Anastomosis, Surgical

Decrease in the single-breath diffusing capacity after saturation dives.

Before and after saturation dives, we measured lung volumes and diffusing capacity (DL(CO)/V(A] with a single-breath method on 12 divers (6 divers per dive) who participated in 300-msw saturation dives (total dive time of 15 days with P(O)2 = 0.42 atm abs) and on 6 divers who were engaged in a 320-msw saturation dive (6 days of bottom time with P(O)2 = 0.42 atm abs and 12 days of total decompression time with P(O)2 = 0.495 atm abs. In all divers, vital capacity right after surfacing did not significantly decrease compared with predive values. In the 300-msw saturation divers after surfacing, DL(CO)/V(A) adjusted for hemoglobin (Hb) changes did not significantly decrease, but in the 320-msw saturation divers Hb-adjusted DL(CO)/V(A) was significantly (P less than 0.001) decreased by 0.70 (mean) +/- 0.21 (SD) (ml.min(-1).mmHg(-1).liter(-1]. These observations indicate that the diffusing capacity is a more sensitive index of pulmonary oxygen toxicity than vital capacity that is traditionally used, and that oxygen partial pressure less than 0.5 atm abs can induce a decrease in pulmonary function.

Diving

[Prevention of cerebral complications during thoracic aortic aneurysms operation: study of preoperative selective cerebral arteriography].

Preoperative selective cerebral arteriography is carried out in order to determine if the circle of Willis is intact in the cases of the thoracic aortic aneurysms. As regard to the bilateral vertebrobasilar communications, 26 of 30 patients (86.7%) have good condition, 4 of 30 patients (13.3%) have poor, and in 2 cases the left vertebral artery supplied broad area of posterior cranial fossa. We believe that in the cases in whom the left vertebral artery is dominant, and cross collateral circulation is absent, perfusion of the left subclavian artery is necessary to prevent vertebrobasilar ischemia during aortic aneurysms operation under normothermia.

Adult

Electron microscopic study of cultured cells from the murine hair tissues: cell growth and differentiation.

The cultured hair cells from 4-day-old C3H mice were studied by electron microscopy. The hair roots isolated from the skin by collagenase digestion were dispersed into a cell suspension by treatment with a mixture of trypsin and ethylenediaminetetraacetate. The cells were cultured in MCDB-153 (a medium containing seven growth factors) for 1, 3, 6 or 13 days. The number of cultured cells on day 3 was twice that on day 1, and stayed at the same level until day 13. By electron microscopy, some of the cells cultured for 1 day were seen to be undifferentiated and others already showed differentiation into various hair structures. Such differentiated cells disappeared on day 3 and most of the cells cultured for 3 days were undifferentiated. Cell cultured for 6 days were differentiated showing inner root sheath cell, hair cortical cell and medulla cell structures. The characteristics of these cultured cells corresponded well to those of in vivo cells of the hair tissues from the back skin of 7-day-old C3H mice. On day 13 degeneration occurred in the cultured cells. In none of these cultures were mesenchymal cells, such as fibroblasts, found. The present electron microscopic study reveals that immature cells obtained from mouse hair tissues proliferate in vitro and differentiate into several subpopulations corresponding to those of in vivo cell layers of hair tissues. The present culture technique may be useful for studies of hair cell growth and differentiation.

Animals

Evaluating marine traffic safety at channels.

An approach for measuring effects of policy schemes for improving marine traffic safety at channels is presented. Operational models involving traffic, channel, and ship characteristics are provided, and both collision and channel deviation risks of actual channels are quantified using them. Moreover, traffic control, speed regulation, and center line indication are considered as channel safety policies, and their effects are also measured using the models. The results suggest that the speed regulation scheme is effective in reducing accident risk in channels. It is concluded that methodology demonstrated and knowledge obtained in this study are useful for planning and safe operation of channels.

Accidents, Traffic

Increased levels of beta-human atrial natriuretic peptide-like immunoreactivity in chronically overloaded atrial tissue.

The levels and molecular form of atrial natriuretic peptide-like immunoreactivity (ANP-LI) in human atrial tissue were investigated. The levels of right atrial ANP-LI were significantly higher in mitral disease than in other cardiac or noncardiac diseases. The increased ANP-LI was mainly accounted for by an increase in beta-human ANP-LI (beta-hANP-LI). Both total ANP-LI and beta-hANP-LI levels were associated with the presence of atrial fibrillation and with increased atrial pressure. Plasma beta-hANP-LI levels were also increased in mitral disease. These results suggest that human atrium with hemodynamic overloads is characterized by increased tissue levels of ANP and by a shift to the beta-hANP form.

Adult

Hypertension and cardiovascular diseases in an epidemiological study in Hokkaido, Japan.

The present study describes the results from the 10-year follow-up data of a prospective epidemiological study for hypertension and cardiovascular diseases in two communities of rural agricultural districts in Hokkaido, Japan. The number of incidences of cerebrovascular accidents (CVAs) in persons who were normotensive, borderline hypertensive (BHT), untreated hypertensive (HT), well-controlled HT [blood pressure (BP) less than 150/90 mm Hg], and poorly controlled HT (BP greater than or equal to 150/90 mm Hg) were 0.46, 3.24, 4.17, 3.49, and 12.76 per 1,000 person-years. respectively: CVAs were markedly high in poorly controlled HT persons. The winter-summer mean BP differences in the first year were significantly and positively correlated with the differences in mean BP between the tenth and the first year, and were significantly higher in the progression to hypertension group than in the nonprogression group in both towns. Multivariate analysis indicated that the winter-summer mean BP difference was a significant variable for indication of progression to hypertension. From these results, we concluded that (a) good control of hypertension could considerably prevent CVA, (b) cold environment may contribute to the progression to hypertension, and (c) winter-summer variation in BP may predict the future course of BP.

Acute Disease

Relationship between NK cells and granulomatous inflammation in mice.

The relationship between natural killer (NK) cells and granulomatous inflammation was investigated using two experimental granuloma models in C57BL/6 mice. The hepatic granuloma model was produced by infection with Schistosoma mansoni (S. mansoni), and the skin granuloma model was established by subcutaneous inoculation of the isolated hepatic granulomas. NK cell activity in lymph nodes and spleen, measured by 51Cr-release assay against YAC-1 cells, was compared to that in age-matched control mice. The activity decreased progressively as granulomas developed without changing the number of NK-1.1+ cells. The reduced NK cell activity was not reversed by administration of indomethacin. In order to further substantiate whether NK cells contribute to granulomatous inflammation, NK cells were depleted in the mice by injection of anti-NK-1.1 mAb. Reduction of NK cell activity (70-90%) was achieved during granuloma formation. An increase of about 20% in the mean granuloma diameter was detected in the mAb-treated mice in both models. Moreover, the percentage of granuloma takes in the skin model was enhanced (65% increase). The mAb treatment did not alter T cell counts in granulomas, T cell subset numbers or proliferative response in spleen. These findings indicate that NK cells directly play a regulatory role in granulomatous inflammation.

Animals

Local effects of granulomatous inflammation on functional activation of T cells in athymic mice.

We investigated the effect of granulomatous inflammation in skin on lymphocyte maturation in athymic (nu/nu) mice. Hepatic egg granulomas developed in euthymic (nu/+) mice with schistosomiasis were transplanted into skin of nu/nu mice. During skin granuloma development the rate of DNA synthesis and interleukin 2 activity of lymphocytes from lymph nodes, with and without concanavalin A stimulation, showed that the nu/nu cells were activated to levels of untreated nu/+ lymph node cells. Activation of splenic lymphocytes was not detected in the grafted nu/nu mice. Also, immunohistochemical staining demonstrated an increase in cells expressing Thy 1.2, Lyt-1 or L3T4 surface markers in the skin and lymph nodes, but not in spleen. The findings indicate that a granulomatous reaction in nu/nu mouse skin induces local, but not systemic, proliferation and differentiation of lymphocytes, to a low degree compatible with resting nu/+ mice.

Animals

[Assessment of infarct-related coronary arteries using the bull's eye view method and unfolded surface mapping in thallium-201 myocardial tomography].

Infarct-related coronary lesions and collaterals were assessed by the bull's eye view and the unfolded surface map derived from thallium-201 myocardial tomography (Tl-201 SPECT) in 25 patients with anterior myocardial infarction. The patients were categorized in six groups according to their cine-angiographic findings: locations of stenosis (proximal or distal portions of the first diagonal branch or distal site of the first septal branch), and the presence or absence of collaterals. The anterior half of the left ventricle on the bull's eye view map was divided into eight regions from the anterior septum to the lateral wall and from the apex to the cardiac base. Tl-201 SPECT images were expressed as functional maps using maximum-count circumferential profile analysis: an "extent image" showing the extent of perfusion defect, and a "severity image" demonstrating the degree of hypoperfusion. The following results were obtained: 1. Perfusion defect of the "extent image" at the basal portion of the anterior septum reflected poor collaterals, with a sensitivity of 81.3%, a specificity of 77.8%, and a diagnostic accuracy of 80.0%. 2. Coronary stenosis at segment 6 (AHA classification) was differentiated from that at segment 7 by detecting hypoperfusion at the basal septum on the "severity image", with a sensitivity of 71.4%, a specificity of 77.8%, and a diagnostic accuracy of 75.0%. 3. Perfusion defect at the basal section of the proximal portion of the anterior wall on the "extent image" indicated stenosis at the proximal segment 6, with a sensitivity of 57.1% and a specificity of 88.9%.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult

[Silent myocardial ischemia in diabetics--by treadmill exercise testing].

We examined silent myocardial ischemia in diabetics by treadmill exercise testing. There were 28 diabetic men and 64 diabetic woman without angina, with a mean age of 59 +/- 11 years. Symptom-limited treadmill exercise testing was performed, and we used the electrocardiogram during exercise and immediately after exercise for judgement. ST segment depression was defined as positive if there was at least 0.1 mV of ST depression 80 ms from the J point. It was defined as negative if max heart rate (HR) was more than 80% of target HR and there was no significant ST depression. It was defined as equivocal if there was no significant ST depression but max HR was less than 80% of target HR. In 92 diabetics, 21 patients (23%) showed positive ST depression, 35 (38%) showed negative ST depression, 36 (39%) showed equivocal ST depression. In 56 diabetics exclusive of treadmill equivocal patients, 38% of patients showed positive ST depression. Treadmill positive diabetics had a significantly higher rate of smokers, patients with hypertension, and a higher triglyceride level as compared with treadmill negative diabetics. Coronary arteriography, which was performed in six treadmill positive diabetics, revealed coronary stenosis of more than 75% in four patients.

Adult

[Prevention of alcohol-induced gastric mucosal injury by prostaglandin E-1].

Effects of ethanol and prostaglandin on the glycoprotein synthesis in the gastric mucus cells have been evaluated. The rat gastric mucosal cell were subjected to a short-term tissue culture in the presence of ethanol and prostaglandin E2 (Ornoprostil), using [3H]-proline, [3H]-palmitic acid, [3H]-galactosamine. Low concentration of ethanol (0.05-0.01 M) stimulated the glycoprotein synthesis, but higher concentration of ethanol (0.5-1.5 M) caused a marked reduction in the glycoprotein synthesis. Addition of prostaglandin E2, especially addition of prostaglandin prior to ethanol treatment, has improved the glycoprotein synthesis and secretion in the presence of ethanol. It was suggested that addition of prostaglandin resulted in the stabilization of the synthesis and secretion of the mucus glycoprotein in the presence of ethanol.

Alprostadil

[Three cases of pulmonary atypical mycobacteriosis associated with lung cancer and adult T-cell leukemia].

Three cases of pulmonary atypical mycobacteriosis (AM) were reported. Two cases were associated with lung cancer in which the diagnosis of malignancy was difficult and delayed by the coexistence of AM. The third was a case of adult T-cell leukemia (ATL) which manifested during the course of AM. In case 1 (73 years, male) and case 2 (86 years, male), chest roentgenogram abnormalities as well as clinical symptoms were considered to be caused by mycobacteriosis because of positive smear of acid-fast bacilli in sputa on admission. Therefore it took four months and three months respectively for final diagnosis of lung cancer. The autopsy of case 1 revealed a poorly differentiated adenocarcinoma with coexisting foci of squamous cell carcinoma in right lower lung, and granulomatous inflammations with caseating necroses in right mid and lower lungs. M. avium complex was cultured from sputum on admission, and also a high titer of HTLV-I antibody was demonstrated. In case 2 malignant cells were detected in sputa (class V), however his general condition did not allow an aggressive anticancer chemotherapy and he died of malignancy with complication of thromboangiitis obliterans on right lower leg. Case 3 was a 76-year-old male who had been diagnosed as lung AM for more than two years. His chest radiography showed bilateral infiltrative shadows with frequent positive cultures of M. avium complex (more than 100 colonies) from sputum. A generalized lymphadenopathy including right hilar lymph node on chest X-ray film was followed by the presence of atypical lymphocytes in peripheral blood and the elevation of HTLV-I antibody in serum. Four months later he died with hypercalcemia and renal failure in spite of chemotherapy (CPM + VCR + ADR + PLS). The above cases suggest that AM as well as tuberculosis should be considered when pulmonary infiltrates were observed in malignant patients, especially in patients with retrovirus infections.

Aged

[Iatrogenic left main coronary artery stenosis following aortic valve replacement: two cases report].

Two cases of iatrogenic left main coronary artery stenosis (ICOS) following aortic valve replacement (AVR) are documented. The first patient began to have chest pain due to myocardial ischemia 7 months after AVR. Angiographically, the ostium of her left coronary artery was severely stenotic. She refused coronary bypass grafting. She died of myocardial infarction due to ICOS, 23 months after AVR. Histologically, a loose cellular connective tissue was found around the stenotic coronary arterial lumen. The other patient had chest pain 4 months after aortic and mitral valve replacement. The ICOS was diagnosed angiographically. After she had coronary bypass grafting, she was free from myocardial ischemic symptoms. The onset of myocardial ischemic symptoms in the first six months after AVR is highly suggestive of ICOS, and urgent coronary angiography is recommended and, if proximal stenosis of the coronary arteries is diagnosed, coronary bypass grafting should be performed.

Adult

Release of PI-anchoring enzymes and other effects of phosphatidylinositol-specific phospholipase C from Bacillus thuringiensis on TN-368 cells from a moth ovary.

Release of PI-anchoring enzymes and other effects of phosphatidylinositol-specific phospholipase C from Bacillus thuringiensis on TN-368 cells from a moth ovary. Toxicon 27, 637-645, 1989.--The effect of phosphatidylinositol-specific phospholipase C(PIPLC) from Bacillus thuringiensis was investigated on TN-368 cells, derived from the ovary of a moth, Trichoplusia ni. Quantitative analysis of lipids showed that phosphatidylinositol (PI) was contained as one of the major phospholipids in TN-368 cells, whereas sphingomyelin and cholesterol were minor lipid components. When TN-368 cells were treated with PIPLC, significant amounts of alkaline phosphatase, 5'-nucleotidase and beta-glucosidase were released from these cells. Thus, these enzymes were shown to be PI-anchoring proteins in the plasma membrane of these cells. In the presence of 4.2 units of PIPLC, the cell growth of TN-368 was inhibited by 50%. In contrast with normal cells, the cells cultured in the presence of PIPLC became swollen and globular, losing their protoplasmic extensions. Also, there was degeneration of the interior of TN-368 cells cultivated in the presence of PIPLC. Mitochondria became swollen with a decrease in number of granules while the crista turned transparent. Also, an increase in lysosomes was observed and vacuoles seemingly derived from smooth endoplasmic reticula appeared.

Animals