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T Kawano

Publications and source records attributed to T Kawano.

At least 343 records · Page 19Linked to original sources
PubMed1989

[A case of mitral valve prolapse simulating mitral tumor or vegetation].

We observed a case of mitral valve prolapse (MVP) mimicking mitral tumor or vegetation. The patient was a 34-year-old man. He complained of palpitation and precordial oppression. Shaggy and mass echoes of the anterior mitral valve were recorded by M-mode and two-dimensional echocardiograms. The "mass" echo was confirmed to by originated in a markedly myxomatous change of the spongiosa layer of the mitral valve at operation. These problems on echocardiographic diagnosis of MVP and mitral "mass", such as mitral tumor or vegetation, were discussed in detail.

Adult↗
PubMed1989

[Two-dimensional and Doppler echocardiographic studies of the genesis of a high-pitched diastolic rumble in mitral stenosis: contribution of the deformed mitral orifice and eccentric mitral inflow jet].

To clarify the genesis of a high-pitched diastolic rumble in mitral stenosis, 51 patients with mitral stenosis were studied. They were subdivided into two groups based on the pitch of a rumble; six patients with a high-pitched rumble and 45 patients with an ordinary low-pitched rumble. Phonocardiography, and M-mode and two-dimensional (2-D) echocardiography were performed in all patients. Color and continuous wave Doppler echocardiography were performed in four patients with a high-pitched rumble and in 13 with a low-pitched rumble. Results obtained were as follows: 1. Points of the maximum intensity of a rumble: A low-pitched rumble was best heard at the apex in all patients. A high-pitched rumble was best heard at the mesoapical area, except in one patient who had an oval mitral orifice by 2-D echocardiography. 2. Correlation between the pitch of rumble and the shape of the mitral orifice: In five of the six patients with a high-pitched rumble, the mitral orifice had a tadpole-shaped deformity, in which commissural fusion and valvular thickening were more marked anterolaterally than posteromedially. Among 45 patients with oval, slit or pinhole-like valve orifices, only one had a high-pitched rumble. 3. Direction of the left ventricular (LV) inflow jet as observed by color Doppler echocardiography: On the short-axis view at the level of the papillary muscles, the inflow jet was directed toward the medial portion of the LV cavity in the patients with a high-pitched rumble. However, it was directed towards the central portion of the LV cavity in all patients with a low-pitched rumble. On the apical long-axis view, no distinct difference was detected in the direction of the LV inflow jet between the two groups. 4. Other findings: There were no significant differences between the two groups in the mitral orifice area, the peak velocity of LV inflow, fractional shortening of the LV, dimension of the left atrium, Wells' index and the degree of organic change in the subvalvular structures. These results suggest that the deformity of the mitral valve and resultant changes in the direction of the LV inflow jet may play an important role in the mechanism of producing a high-pitched diastolic rumble in mitral stenosis.

Adult↗
PubMed1988

Alpha-atrial natriuretic peptide binding sites in the rat choroid plexus are increased in the presence of hydrocephalus.

Specific alpha-rat atrial natriuretic peptide(1-28) [ANF-(99-126)] (rANP) binding sites in the choroid plexus of rats with kaolin-induced hydrocephalus were analyzed following incubation of related tissue sections with 125I-rANP, then using autoradiography and an image analysis coupled with computer-assisted micro-densitometry. The number of 125I-rANP binding sites in the choroid plexus of these rats was significantly higher, as compared to findings in the control rats, whereas no differences in the binding affinity were observed, 3 days and 3 weeks after the intracisternal injection of kaolin. The possibility that atrial natriuretic peptide may play a significant role in the function of cerebrospinal fluid production by interacting with specific, high affinity receptors in the rat choroid plexus has to be considered.

Animals↗
PubMed1988

Structural differences found in the sugar chains of eutopic and ectopic free alpha-subunits of human glycoprotein hormone.

Free alpha-subunits of human glycoprotein hormone were purified from the urine of a healthy pregnant woman and from that of a patient with adenocarcinoma. Comparative study of their sugar moieties revealed that they have different numbers and different sets of asparagine-linked sugar chains, which are also different from those of alpha-subunit obtained by dissociation of whole hCG molecule. The eutopic free alpha-subunit contained biantennary complex-type sugar chains only. In contrast, the ectopic free alpha-subunit contained tri- and tetraantennary complex-type sugar chains in addition.

Adenocarcinoma↗
PubMed1988

Piston-pump-type high frequency oscillatory ventilation for neonates with congenital diaphragmatic hernia: a new protocol.

High frequency ventilation and extracorporeal membrane oxygenation (ECMO) are devices that are expected to save the lives of newborn infants whose pulmonary conditions have deteriorated. A piston-pump-type high-frequency oscillator (HFO), developed by Bryan and Miyasaka called "Hummingbird," is considered to be superior to high frequency "jet" ventilators or those of the flow-interrupter type, and was used successfully in two neonates with congenital diaphragmatic hernia (CDH) in a high-risk group. The first baby was on a conventional ventilator with pharmacologic support for the first 54 hours and then operated on. Postoperative deterioration necessitated the use of HFO for the next eight days. The infant then recovered uneventfully. For the second baby, HFO was necessary both preoperatively and postoperatively. This baby had a major diaphragmatic defect and her case was complicated with pneumothorax. There was a long stormy course on HFO (total, 70 days), but the patient was successfully extubated on the 75th day postoperatively and is now doing well. We believe active long preoperative stabilization with pharmacologic support and preoperative and postoperative hyperventilation with a piston-pump-type HFO may be a new innovative strategy for the management of severe CDH patients.

Female↗
PubMed1988

Effect of increased surface tension and assisted ventilation on 99mTc-DTPA clearance.

Experiments were performed to determine the effects of conventional mechanical ventilation (CMV) and high-frequency oscillation (HFO) on the clearance of technetium-99m-labeled diethylenetriamine pentaacetate (99mTc-DTPA) from lungs with altered surface tension properties. A submicronic aerosol of 99mTc-DTPA was insufflated into the lungs of anesthetized, tracheotomized rabbits before and 1 h after the administration of the aerosolized detergent dioctyl sodium sulfosuccinate (OT). Rabbits were ventilated by one of four methods: 1) spontaneous breathing; 2) CMV at 12 cmH2O mean airway pressure (MAP); 3) HFO at 12 cmH2O MAP; 4) HFO at 16 cmH2O MAP. Administration of OT resulted in decreased arterial PO2 (PaO2), increased lung wet-to-dry weight ratios, and abnormal lung pressure-volume relationships, compatible with increased surface tension. 99mTc-DTPA clearance was accelerated after OT in all groups. The post-OT rate of clearance (k) was significantly faster (P less than 0.05) in the CMV at 12 cmH2O MAP [k = 7.57 +/- 0.71%/min (SE)] and HFO at 16 cmH2O MAP (k = 6.92 +/- 0.61%/min) groups than in the spontaneously breathing (k = 4.32 +/- 0.55%/min) and HFO at 12 cmH2O MAP (4.68 +/- 0.63%/min) groups. The clearance curves were biexponential in the former two groups. We conclude that pulmonary clearance of 99mTc-DTPA is accelerated in high surface tension pulmonary edema, and this effect is enhanced by both conventional ventilation and HFO at high mean airway pressure.

Animals↗
PubMed1988

Striatal dopamine in acute cerebral ischemia of stroke-resistant rats.

We devised the present experiments to assess the effects of ischemia on the production of dopamine in the caudate nucleus of spontaneously hypertensive stroke-resistant rats. Ringer's solution was continuously perfused at a rate of 10 microliters/min through 0.2-mm-diameter dialysis tubing implanted in the rat's caudate nucleus. After bilateral occlusion of the common carotid artery, perfusate was collected at 20-minute intervals for 120 minutes and was analyzed for monoamines and their metabolites using high-performance liquid chromatography and an electrochemical detection system. The extracellular concentration of dopamine increased abruptly approximately 3 minutes after the ischemic insult, reached a maximum at between 20 and 40 minutes after the insult, and subsequently decreased. During the 120 minutes, 3,4-dihydroxyphenylacetic acid and 5-hydroxyindole-3-acetic acid concentrations decreased significantly, whereas 5-hydroxytryptamine was not detected. Our results indicate that during cerebral ischemia a large increase in extracellular dopamine concentration in the caudate nucleus occurs, probably as a result of energy failure of the cell membranes. This leakage of dopamine may be a causal factor in the neuronal damage associated with cerebral ischemia.

3,4-Dihydroxyphenylacetic Acid↗
PubMed1988

Effect of RU 486 on luteal function in the early pregnant rat.

A dose of 30 mg RU 486/kg, an antiprogesterone, was administered to pregnant rats on Day 2 (Group 1) or Day 4 (Group 2) of pregnancy. RU 486 significantly changed serum progesterone and oestradiol concentrations and luteal 3 beta-HSD and 20 alpha-HSD activities in Group 1, and implantation was significantly inhibited. The luteal 3 beta-HSD activity in Group 2 rats on Day 6 was significantly (P less than 0.01) lower than the control value (7.5 +/- 0.6 and 10.1 +/- 0.6 mU/mg protein respectively). This decline in the 3 beta-HSD activity was followed by a marked decrease in the serum progesterone concentration, resulting in a significant decrease of the progesterone/oestradiol ratio and implantation was completely inhibited. The 20 alpha-HSD activity, which could not be detected on Day 6 in the control rats, was twice as great in Group 2 than in Group 1 rats (17.5 +/- 1.2 and 7.4 +/- 3.1 mU/mg protein respectively). Ultrastructural examination of corpora lutea of Group 2 rats confirmed luteolysis. These results suggest that RU 486 has a luteolytic effect and its anti-implantation effect is concomitant with luteolysis of the corpora lutea of pregnancy.

20-Hydroxysteroid Dehydrogenases↗
PubMed1988

[A case of preoperative esophageal cancer developing lobar pneumonia due to MRSA infection of the catheter].

The 65-year-old male patient of esophageal cancer before operation suffered from lobar pneumonia. Bacteriological examination identified MRSA in his sputum and catheter tip. None of the cefem type antibiotics were effective, but CLDM and MINO were so much effective against that. We studied 47 cases of esophageal cancer which received operation last year. In many bacteria which were identified in the sputum and pus, MRSA occupied 30% as well as Pseud. aeruginosa. In the preoperative period enteral nutrition (ED) may be acceptable, if possible, as nutritional support alternative to TPN.

Aged↗
PubMed1988

[Genesis and clinical significance of the "low-pitched" aortic ejection sound].

The genesis and clinical significance of the aortic ejection sound with a low-frequency predominance and delayed appearance were studied. This is recorded on the phonocardiogram in some patients with left ventricular dysfunction. Subjects studied consisted of 10 patients with a low-pitched ejection sound and seven patients with an ordinary high-pitched aortic ejection sound. No patients had echocardiographic findings suggestive of organic lesions of the aortic valve. Time relationships among the ejection sounds, aortic valve echograms and carotid artery pulses, and then movements of the aortic valve cusps and non-invasively estimated left ventricular systolic function were compared between the two groups. Results were as follows: 1. The low-pitched ejection sound: 1) The beginning of the sound was nearly coincident with the onset of the upstroke of the carotid artery pulse and the initial full opening of the aortic valve cusps. 2) The beginning of the ejection systolic murmur followed immediately after the ejection sound. 3) The amplitude of the sound was closely related to the height of the carotid artery pulse in a case of atrial fibrillation. 2. The low-pitched ejection sound vs the high-pitched ejection sound: 1) The onset of the low-pitched ejection sound was significantly delayed. 2) The amplitude and the velocity of the initial opening of the aortic valve cusps were significantly decreased. 3) The preejection period (PEP) was significantly prolonged; the ejection time (ET) was significantly shortened; and the PEP/ET ratio was significantly increased.(ABSTRACT TRUNCATED AT 250 WORDS)

Aorta↗