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Biomedical subjects

Y Koga

Publications and source records attributed to Y Koga.

At least 397 records · Page 22Linked to original sources
PubMed1989

Lymphocyte subsets in patients with acute myopericarditis, arrhythmias and dilated cardiomyopathy.

To investigate the role of immunoregulatory function in determining the clinical course of acute myopericarditis, lymphocyte subsets were analysed by laser flow cytometry in 20 patients with acute myopericarditis, 30 with various arrhythmias or atrio-ventricular block and 31 with dilated cardiomyopathy. During the healing stage of acute myopericarditis, patients with residual electrocardiographic or left ventricular wall motion abnormalities presented altered frequencies of lymphocyte subsets, increased B 1 and reduced OKT 8 positive cells with an elevated OKT 4/8 ratio. The abnormal pattern was not evident in patients with acute pericarditis nor in those with acute myocarditis who recovered completely without residual abnormalities. This observation suggested that an imbalance of helper/suppressor T cells could modulate the clinical course of acute myopericarditis, either by producing extensive and irreversible myocardial damage during acute illness or by inducing chronic smoulding myocardial inflammation. Patients with ventricular arrhythmias and left ventricular wall motion abnormalities also presented reduced suppressor/cytotoxic T cells, implying that they had been suffering from chronic smoulding myocarditis mediated by immunoregulatory dysfunction. However, we could not determine whether the imbalance of helper/suppressor T cells could mediate the progression from myocarditis to dilated cardiomyopathy, since no association was demonstrated between the abnormal lymphocyte subsets and mononuclear cell infiltration in endomyocardial biopsy sample from patients with dilated cardiomyopathy.

Acute Disease↗
PubMed1989

Relaxation of airway smooth muscle induced by potassium in the presence of Ca-antagonists.

We examined K+-induced relaxation instead of contraction in the presence of Ca-antagonists by measuring isometric tension in the tracheal smooth muscle isolated from guinea pigs. Cumulative administration of KCl (10-90 mM) induced a concentration-dependent contraction. When the muscle was pretreated with low concentrations of Ca-antagonists, cumulative administration of KCl caused a mild contraction, followed by a moderate relaxation. In the muscle pretreated with high concentrations of Ca-antagonists, KCl revealed a concentration-related relaxation without contraction. The potency ratios of Ca-antagonists to reverse the KCl-induced contraction to relaxation were nifedipine : verapamil : diltiazem = 94:4:1. This order of potency was quite similar to that of Ca-antagonists to relax the muscle precontracted with KCl (30 mM). Magnitudes of KCl (30 m,)-induced relaxation in the presence of Ca-antagonists were similar to those caused by Ca-antagonists in the KCl (30 mM)-precontracted muscles. Thus, K+-induced relaxation in the airway smooth muscle in the presence of Ca-antagonists may be due to the voltage-dependent increase in binding of Ca-antagonists to calcium channels.

Animals↗
PubMed1989

Reinforcement of the anastomosis between the fragile arterial vessel and the prosthetic graft. A headband method.

A new method of anastomosis was devised, intended for the reinforcement of the anastomosed area between the fragile vessel of the patient and the prosthetic graft in cardiovascular surgery. This method, which may be called a headband method, consists of suturing a small prosthetic graft wrapping the anastomosed area together with the arterial vessel in the manner of a headband. Fourteen cases have been evaluated at follow-up periods ranging from 24 to 40 months. All cases proved successful without noteworthy complications.

Anastomosis, Surgical↗
PubMed1989

[Contents and molecular forms of human atrial natriuretic peptide in right and left auricle in patients with heart disease].

Contents and molecular forms of human atrial natriuretic peptide (hANP) in right and left auricle were analyzed by reverse phase high liquid chromatography (RP-HPLC), coupled with radioimmunoassay for hANP. Analyses were done with auricles taken from 4 autopsied cases without heart disease, and 13 patients with heart disease. Both right and left auricular hANP contents in patients with heart disease were higher than those obtained at autopsy. In patients with mitral stenosis (MS) or mitral regurgitation (MR) who have left atrial pressure and/or volume overload, hANP contents in left auricle were higher than those in right auricle. In addition, three types of molecular forms of hANP, (gamma) type, (alpha, beta, gamma) type, (beta, gamma) type, were observed in both right and left atrium. In patients with MS or MR, (beta, gamma) type or (alpha, beta, gamma) type which have beta-hANP immunoreactivity were observed in 8 out of 9 in patients in left auricle, however, in 4 out of 9 patients in right auricle. Our results suggested that the difference of contents and molecular forms of hANP may reflect the pathophysiological role in heart diseases.

Adult↗
PubMed1989

[Concentric left ventricular hypertrophy in patients with aortic regurgitation].

Chronic aortic regurgitation (AR) is a disease incorporating volume overload of the left ventricle (LV) which is characterized by hyperactive left ventricular dilatation (LVD). However, we have encountered several patients who had concentric LV hypertrophy (LVH) instead of LVD. We therefore studied 50 consecutive patients with isolated AR but without aortic stenosis and found seven patients with concentric LVH having LV wall thickness (determined by summing ventricular septal and posterior wall thicknesses) exceeding 30 mm and LV diastolic diameters of less than 60 mm. These seven patients with AR and LVH were older (55 +/- 27 vs 42 +/- 11 years) and tended to have milder degree of AR, compared with the remaining 43 patients having AR and LVD. However, patients with AR and LVH did not differ from AR and LVD as to the cardiothoracic ratio, SV1 + RV5, T-waves, ejection fraction, operative findings of valvular morphology and underlying etiologies. In contrast, patients with AR and LVH presented higher systolic (196 +/- 41 vs 149 +/- 26 mmHg, p less than 0.01) and diastolic pressures (74 +/- 14 vs 51 +/- 13 mmHg, p less than 0.01) and higher systemic vascular resistance (1,854 +/- 399 vs 1,388 +/- 352 dyne.sec.cm-5, p less than 0.05) during catheterization than did those with AR and LVD. However, blood pressure at the time of admission was not different in the two groups. These observations indicate that concentric LVH is not rare among patients with AR, and that an association of pressure overload with volume overload of the LV, particularly during exercise or stress, may lead to concentric LVH, even in patients with chronic AR.

Adult↗
PubMed1989

[A case of giant mediastinal cystic lymphangioma].

A 13 year-old boy was admitted because of anterior chest pain, fever up and exertional dyspnea. Chest X-ray film showed a large mass shadow on the middle and lower lung field with positive silhouette sign. Under the ultra-sonic tomogram the mass showed cystic pattern with septum. The bloody fluid collected by puncture suggested hemorrhage into the cyst. Chest CT scan revealed a well defined cystic mass in the left thoracic space. The mass reached to the right thoracic space through behind the Inferior Vena Cava (IVC). At operation, although the tumor adjoined heart, esophagus, diaphragma and IVC, it was removed completely. Pathological diagnosis was cystic lymphangioma.

Adolescent↗
PubMed1989

[Myocardial protection of temperature].

The effects of myocardial temperature on 120-minute preserved hearts were studied on heterotopically transplanted hearts of rats of isogeneic strain. Rats were divided in the following groups; the control group, the 0 degree C preservation group, the 5 degrees C group, the 10 degrees C group, the 15 degrees C group and the 20 degrees C group. Experiments were divided into the acute stage experiments and chronic stage experiments. The former included electron microscopic studies of the myocardium of heart transplants and serum enzymes of recipients. In the chronic stage experiments, the percentage of fibrosis was compared as an index of success. No hearts of the 20 degrees C group resuscitated, and by the indices of acute stage experiments, the 10 degrees C group and the 15 degrees C group showed considerable impairment; other groups showed less damage of the same degree. The chronic stage experiments indicated that the 0 degree C group was best, followed by the 5 degrees C group in the increasing order of temperature, evaluated by the rate of fibrosis. It may be concluded that hypothermia close to the freezing point has the best protective effects on the myocardium. Cold injury, even if present, may be transient and not harmful when ischemia is about 120 minutes. Comprehensive evaluation of various factors contributing isograft survival should include not only various methods examined in the acute stage but also an over-all evaluation of fibrosis in the chronic stage, since the myocardium of the graft shows a variability of findings in the acute stage.

Animals↗
PubMed1989

[Right ventricular regional wall motion and function after tetralogy repair].

The right ventricular (RV) function is very important after correction of tetralogy of Fallot (TOF) similarly to left ventricular (LV) function. The influence to RV contraction caused by RV outflow tract patch after repair of TOF is serious. There are a few literatures about contraction mode of RV but we can't see any reports about regional RV wall motion before and after surgery of TOF. This paper is the first report about RV regional wall motion and function after 20 cases of tetralogy repair. We would emphasize the following points. 1) Regional wall motion of RV at antero-basal and anterolateral is getting worse but is improved at anteroapical of RV. 2) Appropriate rate of RV systolic pressure to LV systolic pressure just after weaning from cardiopulmonary bypass and rate of patch length to RV length is below 0.5 and 0.4 respectively. 3) There is positive correlation between RV ejection fraction and wall motion at anteroapical of RV.

Child↗
PubMed1989

[Evaluation of hepatic function by hepatobiliary scintigraphy using factor analysis].

Factor analysis of hepatobiliary scintigraphy using 99mTc-N-pyridoxyl-5-methyltryptophan (99mTc-PMT) was performed, and functional factor of liver parenchyma (FA-hepatogram) was obtained. Two parameters (peak time, T 1/2) were calculated from this hepatogram. A good correlation was obtained between these parameters and ICG-R15; furthermore, these parameters were prolonged in patients with normal volunteers, chronic hepatitis, compensated and decompensated liver cirrhosis in this order. Conventional hepatogram by ROI method (ROI-hepatogram) was not suitable for the evaluation of global liver function in condition such as a large intrahepatic mass, intrahepatic gall bladder, dilatation of biliary tree, and severe liver cirrhosis. But, even in such cases, FA-hepatogram was useful for the evaluation of global liver function.

Biliary Tract↗
PubMed1989

[A case report of bronchial rupture with a polyvinylchloride (PVC) double-lumen tube].

The patient is a 58-year-old man with a 3-months history of painful swallowing. Endoscopy and biopsy demonstrated squamous cell carcinoma of the middle one third of the esophagus. On Sept. 13, 1987, the patient underwent surgery. The patient was intubated with the PVC double-lumen tube. After the resection of esophagus, when lymphadenectomy was performed, we noticed the herniation of a bronchial cuff through the left main bronchial tear. Surgical repair of the lesion was accomplished with a continuous suture with 3-0 vicryl. Subsequent course of the patient was uneventful. Tracheobronchial rupture is rare complication of intubation with PVC double-lumen tube. This complication results from measures such as using an inadequate tube size, malpositioning the tip of the tube, or insufflating the balloon too rapidly, which dose not allow adaptation of the balloon to the tracheobronchial wall. In our case, overinflation of the bronchial balloon was probably the etiology of rupture. This was probably secondary to diffusion of nitrous oxide, rather than initial over-distension. Meticulous cares must be emphasized to avoid such complication.

Bronchi↗
PubMed1989

[Yersinia enterocolitis--report of two cases].

We reported two cases of terminal ileitis caused by Yersinia enterocolitica (Y.e.). Y.e. was proven by stool culture in each case. They were admitted to the hospital complaining abdominal pain. They are examined by X-ray and endoscopy in the different time, and their examination revealed edema, coarse mucosa and varioliform elevated lesions with the passage of time.

Adult↗
PubMed1989

[A case of Morgagni's hernia complicated with esophageal hiatus hernia].

A rare case of Morgagni's hernia complicated with esophageal hiatus hernia is reported. A 85-year-old female suffered from swallowing disturbance admitted for evaluation of abnormal finding on chest X-ray film. The diagnosis was confirmed by chest roentgenogram, gastro-intestinal series and CT scan. Satisfactory repair was performed by the transabdominal approach and the postoperative course was excellent without any complication.

Aged↗
PubMed1988

Cardiovascular interaction between sevoflurane and nicardipine in open chest dogs.

Cardiovascular interaction between nicardipine and sevoflurane was examined in dogs and compared with nicardipine-thiopental interaction and nicardipine-halothane interaction. The bolus intravenous injection of nicardipine at dosages of 15 micro g/kg and 30 micro g/kg under sevoflurane anesthesia produced transient decreases in blood pressure, systemic vascular resistance, left ventricular pressure, left ventricular (dp)/(dt) and -(dp)/(dt), and a slight increase in cardiac output. The degrees of these changes were almost identical to those under thiopental or halothane anesthesia. Left and right atrial pressure, pulmonary arterial pressure, pulmonary vascular resistance were not changed by nicardipine under any of the three anesthetics. These results suggest that the cardiovascular interaction of nicardipine and sevoflurane is additive and similar to that of nicardipine and halothane and that the cardiovascular changes induced by nicardipine are not modified by the presence of anesthetics.

Journal Article↗
PubMed1988

Expression of the human T-cell-specific tyrosine kinase YT16 (lck) message in leukemic T-cell lines.

To evaluate the role of the human T-cell-specific tyrosine kinase lck (YT16), we measured the levels of lck expression in thymocytes, peripheral T-cells, and leukemia T-cell lines which are arrested at different stages of thymic differentiation. The results indicate that higher levels of the lck message can be found in total thymocytes and T-cells arrested at Stage III (thymocytes that have rearranged their alpha, beta, and gamma chain T-cell receptor genes). A 20-fold lower level of these transcripts, however, can be found in cells derived from Stage I cells (thymocytes with germline alpha, beta, and gamma genes), 4 times less messages in Stage II cells (thymocytes with rearranged gamma and beta chain genes, but with germline alpha chain genes), and a 4-fold lower amount of RNA in Stage IV cells (mature lymphocytes). Culture of these cells with a variety of inducing reagents indicated that leukemia cell lines of only Stages I and II can be induced to increase their levels of YT16 expression by the addition of tetradecanoyl phorbol-13-acetate. These results suggest that there may be a developmental regulation of these tyrosine kinase messages during T-cell ontogeny. The high level of these transcripts in more mature T-cell leukemia lines suggests that they may primarily play a role in the proliferative controls of these cells.

Antibodies, Monoclonal↗
PubMed1988

Findings in muscle in complex I (NADH coenzyme Q reductase) deficiency.

Thirteen of 15 patients with complex I deficiency had the multisystemic form, with strokelike episodes and other symptoms that fulfilled the diagnostic requirements for MELAS (mitochondrial myopathy, encephalopathy, lactic acidosis, and strokelike episodes), and 2 had only muscle fatigability and weakness, having the purely myopathic form. In the multisystemic form, 12 patients had ragged-red fibers. All multisystemic patients had myopathic histochemical abnormalities that consisted of mild to moderate variation in fiber size, disorganized intermyofibrillar networks, type 2 fiber atrophy, and an increased number of type 2C fibers. Five of 13 multisystemic patients had decreased cytochrome c oxidase (CCO) activity in extrafusal fibers, with sparing of intrafusal muscle fibers. In the myopathic form, pathological findings were similar to those in the multisystemic form. In addition to complex I and NADH dehydrogenase activities being decreased, the CCO activity was significantly decreased (less than 50% of control value) in 8 patients, especially when the disease was in its advanced stages, suggesting that CCO enzyme might be secondarily affected as the disease progresses.

Adolescent↗
PubMed1988

A long term follow up of resection interposition arthroplasty of the knee using chromicized fascia lata.

We have reviewed the results of 25 patients who had a resection interposition arthroplasty of the knee using chromicized fascia lata, with a mean follow-up of 22 years. No patient had severe pain although 10 had occasional pain after heavy labour. Thirteen knees had 60 degrees of movement or more but 12 had 45 degrees or less. The radiographs all showed adaptive remodelling of the resected bone ends. This procedure successfully restored function in the majority of cases with absence of pain over a long period.

Adolescent↗