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Biomedical subjects

Y Sakai

Publications and source records attributed to Y Sakai.

At least 775 records · Page 43Linked to original sources

An infertile man with a 45X karyotype.

We describe an infertile man with normal secondary sexual characteristics and a 45X karyotype. Physical examination showed bilateral soft small testes and the semen contained no sperm. Serum testosterone, estrogen and gonadotropin levels were within normal range. Biopsy of the testis showed germinal aplasia.

Adult↗

Graft transection and warm perfusion in situ in canine partial orthotopic liver transplantation.

Liver transplantation is now proven therapy for various forms of end-stage liver disease in children; however, the problem of donor liver shortage remains. To investigate the feasibility of graft procurement from living, genetically related adult donors without injury to either donor or recipient, partial orthotopic liver transplantation (PLT) using a graft transected and warm perfused in situ was evaluated in beagles; the viability of the graft was assessed in terms of energy metabolism, including blood ketone body ratio (KBR), as well as of recipient survival. PLT was performed in two groups with venovenous bypass. The left half of the donor liver was transected in situ, flush perfused with 2 l lactated Ringer's solution (4 degrees C in group A, 20 degrees C in group B), and immediately implanted into the recipient, who was totally hepatectomized, care having been taken to leave the inferior vena cava intact. Four of seven dogs survived for 5 days or longer (longest, 8 days) in group A and six of eight dogs (longest, 20 days) in group B. Causes of death were gastrointestinal bleeding, intussusception, or infection but not graft dysfunction. In both groups the KBR decreased significantly during the anhepatic period, recovered rapidly to the pre-anhepatic level after revascularization, and was maintained within a normal range thereafter. No significant differences in the time course of changes in KBR were seen between the two groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

Production of Formaldehyde by Detergent-Treated Cells of a Methanol Yeast, Candida boidinii S2 Mutant Strain AOU-1.

Treatment of cells of a methanol yeast, Candida boidinii, with the cationic detergent cetyldimethylbenzyl-ammonium chloride (Cation M2) improved the production of formaldehyde. Formaldehyde production was improved twofold with respect to the initial amount of formaldehyde and 1.61-fold with respect to the final amount of formaldehyde after a 12-h reaction under optimized detergent treatment conditions. The treatment caused formaldehyde and formate dehydrogenases to leak out of the cells more rapidly than catalase, but there was no leakage of alcohol oxidase. The improvement in formaldehyde production was considered to be due to the increased permeability of yeast cell membranes and to lower activities of formaldehyde and formate dehydrogenases in Cation M2-treated cells than in intact cells. Changes in the ultrastructure of the cells were observed upon Cation M2 treatment. Several developed peroxisomes were observed in intact cells. After Cation M2 treatment, the cells were obviously damaged, and several peroxisomes seemed to have fused with each other.

Journal Article↗

Bacterial interference in mixed infection in the rat bladder.

Interaction between Escherichia coli and Pseudomonas aeruginosa was studied in chronic bladder infection made in male Wistar rats by implanting a knotted silk thread holding organisms into the bladder. Strains isolated from patients were used. The number of organisms in bladder urine was measured 1 week after the inoculation. When E. coli and P. aeruginosa were inoculated simultaneously, P. aeruginosa grew less well than when inoculated alone. When P. aeruginosa was inoculated into the bladder colonized with E. coli, P. aeruginosa was almost always unable to grow in the bladder, while E. coli inoculated into the bladder colonized with P. aeruginosa was able to grow there in many animals. Bacteriocin activity had nothing to do with the results. These results indicate that E. coli interferes with the growth of P. aeruginosa in mixed infection in the bladder.

Animals↗

New diagnostic evidence on the T wave map indicating involved coronary artery in patients with angina pectoris.

To define the clinical significance of T wave map changes in patients with angina at rest, body surface isopotential T distributions were obtained in 48 patients with single-vessel disease (left anterior descending artery, 34; right coronary artery, eight; left circumflex artery, six) documented angiographically and were compared with those in 120 healthy subjects and those in 19 patients with left ventricular overload whose electrocardiograms showed negative T waves accompanied by an increase in R wave amplitude in left precordial leads. The T wave map abnormalities were observed in 24 of 48 patients (50%) with angina and were classified into three types: (1) type I (18 patients, 37.5%) was characterized by a segmental negative potential in the positive area located at the left thorax and the minimum at the peak of T wave positioned in the upper portion of the left anterior chest, (2) type II (three patients, 6.3%) was characterized by a negative potential with a minimum in the inferior thorax and an indentation of negative potential at the lower margin of the positive potential located over the upper thorax, and (3) type III (three patients, 6.3%) was characterized by a negative potential with a minimum at the back throughout the period of T wave. All patients showing T wave map abnormalities of type I had a significant stenosis of the left anterior descending artery. Likewise, all patients with type II or III had single-vessel disease of the right coronary or left circumflex artery, respectively. All types of T wave map changes observed in patients with angina were different from those in patients with left ventricular overload, whose maps showed the generalized negative potential at the inferior thorax and the left back and the minima clustered at the precordium. In seven patients with lesions of the left anterior descending artery, T wave map abnormalities of type I recovered to normal after successful percutaneous transluminal coronary angioplasty. The behavior of the negative potential and its extrema on the T wave map, which was not available from routine electrocardiography, was indicative of the involved coronary artery and probably of its associated ischemic area in one-half of our patients with angina pectoris.

Adult↗

Coronary artery aneurysms and congestive heart failure--possible long-term course of Kawasaki disease in an adult--a case report.

Multiple coronary artery aneurysms, rarely seen in patients with atherosclerotic heart disease, can be frequently observed in children with Kawasaki disease. However, their long-term clinical courses still remain obscure. A thirty-nine-year-old male came to our clinic because of congestive heart failure. A left ventriculogram revealed highly reduced wall motion. A coronary angiogram showed left main trunk aneurysm with complete occlusion of the left anterior descending artery and ramification of the right coronary artery close to the ostium. Six months after discharge, he died suddenly. On autopsy, aneurysms were observed in the left main trunk and right coronary artery, together with an old anteroseptal myocardial infarction. Although he did not have a clear history of febrile disease in childhood, he was highly suspected to be a long-term survivor of Kawasaki disease because of the unique form and distribution of the coronary artery aneurysms.

Adult↗

Effectiveness of continuous arteriovenous hemofiltration for patients with refractory heart failure.

Continuous arteriovenous hemofiltration (CAVH) was carried out in 8 patients with refractory congestive heart failure. All these patients had heart failure and oliguria for over 24 hours and intensive treatment with digitalis, diuretics, catecholamines and vasodilators was prescribed. Hemodynamics were followed closely during CAVH. During CAVH, pulmonary arterial pressure and pulmonary capillary wedge pressure were significantly reduced in all patients, the right atrial pressure decreased in 6 with right cardiac failure, the heart rate decreased in 3 with tachycardia and the blood pressure and cardiac index were elevated in 3 with hypotension. These observations show that CAVH can be performed safely and effectively in patients with congestive heart failure, oliguria and hypotension.

Adult↗

Stereotyped phrenic response to laryngeal afferent volleys: the mechanism and anesthetic sensitivity.

The stereotyped reflex changes in phrenic discharge, produced by train(s) of electrical shocks to myelinated afferents in the internal branch of the superior laryngeal nerve (SLN), were studied in vagotomized cats and rabbits, mechanically ventilated with the mixture of oxygen and nitrous oxide. Single weak shocks caused a short latency (4-5 msec) phrenic response, an excitation followed by a slight inhibition for 10 msec, which was repeatable at a rate of 200 Hz or more. Repeated weak shocks at a rate higher than 100 Hz or single stronger shocks caused a powerful inhibition with a limited duration (25-30 msec) of both the central inspiratory activity (CIA) and short latency response. This stereotyped inhibition, which was followed by a rebound excitation, could occur every 30-50 msec with some reduction and was apparently associated with a decreased slope of integrated phrenicogram. During inhalation of halothane (0.5-1.5%), the short latency phrenic response was reduced, while the stereotyped inhibition and the reduction of phrenic augmentation were markedly enhanced when the CIA was slightly depressed by halothane inhalation. Therefore, the stereotyped inhibition produced by myelinated laryngeal afferents.

Action Potentials↗

Ultrasonic evaluation of cervical metastatic lymphadenopathy.

We investigated the location, size, and shape of cervical lymph nodes in head and neck cancer, using a 7.5-MHz ultrasound scanner. First, the different criteria for normal size were obtained for cervical lymph nodes in each region; lymph nodes greater than 9 mm in thickness in the internal jugular chain or greater than 7 mm in thickness in the submandibular and submental chains should be suspected of harboring metastatic foci. Second, metastatic nodes showed a more rounded configuration than nonmetastatic ones. Third, a comparative study of metastatic lymph nodes between the in vivo and in vitro ultrasonograms and the corresponding histopathological findings disclosed that an echogenic region in an ultrasonogram of a metastatic node was caused by coagulation necrosis, and a cystic area of liquefaction necrosis.

Carcinoma, Squamous Cell↗

[Nutritional assessments in the long-term survivors following massive resection of the small intestine].

Nutritional assessments were measured in the sixteen long-term survivors who had undergone a massive resection of more than two-thirds of the small intestine or less than 170 cm of the remaining small intestine. Prealbumin, retinol binding protein and zinc in serum and arm muscle circumference were significantly lower than the normal range. Serum albumin had a tendency to correlate to the length of the remaining small intestine. Nutritional risk index had a correlation with the length of the remaining small intestine. In this study, nutritional assessments in the patients with a massive resection of the small intestine indicated to be in preclinical malnutritional state. This may support that supplementary nutritional therapy is necessary for such patients. In addition, we reported a patient with sensory polyneuropathy caused by vitamin E deficiency due to short bowel syndrome. The level of vitamin E was low in his serum, 294 micrograms/dl (normal: 1004 +/- 65) and in his red blood cells, 136 micrograms/dl (normal: 176 +/- 9). His symptom was markedly decreased within two weeks after the administration of large doses of vitamin E.

Adolescent↗

[A case of advanced gastric cancer responsive to intratumoral OK-432 injection].

An 83-year-old patient with advanced gastric cancer was given repeated endoscopic administration of OK-432 combined with systemic immunochemotherapy. The cancerous lesion gradually regressed following the treatment, and remarkable degeneration was observed in many tumor cells. Detailed immunohistochemical examination revealed that Leu 7-positive cells had markedly infiltrated the cancerous tissue. This finding suggests that NK cells may play an important role in tumor regression induced by intratumoral OK-432 therapy.

Adenocarcinoma↗

NMDA-receptors on Purkinje cell dendrites in guinea pig cerebellar slices.

The Mg2+-dependent depolarizing action of N-methyl-D-aspartate (NMDA) was intrasomatically investigated, in comparison with quisqualate (QA), in Purkinje cells in cerebellar slices from adult guinea pigs. NMDA applied iontophoretically to the proximal dendritic region (about 100 micron from the Purkinje cell soma) induced depolarizations and spike firings in about the half of the Purkinje cells tested in nominal Mg2+-free medium (contaminated with 4-11 microM Mg2+), and 1 mM Mg2+ almost completely blocked this NMDA action. Application of NMDA onto the distal dendritic region (about 200 micron from the soma) caused no depolarization at all even in the Mg2+-free medium. QA applied onto either the proximal or distal dendritic region consistently showed Mg2+-independent depolarizations. The amplitude of NMDA-induced depolarization in the Mg2+-free medium was non-linearly related to the membrane potential, i.e. smaller at a hyperpolarized potential level. 2-Amino-5-phosphonovalerate blocked the NMDA action partially but more selectively than the QA action, while the reverse was the case for glutamic acid diethylester. These results suggest that the Mg2+-dependent, NMDA-sensitive receptor, which is distinct from the QA receptor and probably similar to the well-known NMDA receptor, is present on the proximal dendrite of the cerebellar Purkinje cell of the guinea pig.

Animals↗