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K Yashiro

Publications and source records attributed to K Yashiro.

At least 73 records · Page 4Linked to original sources
PubMed1991

Possible role of Streptococcus pyogenes in mucocutaneous lymph node syndrome. XII. Variable responses of platelets in MCLS seem to be explainable by streptococcal pyrogenic exotoxin.

As a model system for mucocutaneous lymph node syndrome (MCLS), we have advocated and used mice which had been rendered tolerant to Streptococcus pyogenes-associated antigens by neonatal infection with group A beta-hemolytic streptococci, because these mice have shown a variety of peculiar bioimmunological characteristics bearing a striking resemblance to those of MCLS patients. The results of our current investigations reaffirmed the reliability of the animal model by indicating that mice subjected to neonatal infection with S. pyogenes, or inoculation with streptococcal pyrogenic exotoxin (SPE) in Freund's adjuvant, were perfect counterparts of patients with MCLS on account of their platelet activation and hyperaggregability in response to provocative treatment, which are familiar findings in this disease.

Animals↗
PubMed1991

Possible role of Streptococcus pyogenes in mucocutaneous lymph node syndrome XIII. No recovery of beta-hemolytic streptococci from pharynx of MCLS patients.

Lack of recovery of beta-hemolytic streptococci from the throat of 80 patients finally diagnosed as mucocutaneous lymph node syndrome was again confirmed, although alpha-hemolytic streptococci were consistently isolated from all patients but one. The implications of these findings were discussed, particularly in terms of the possible role of Streptococcus pyogenes in the pathogenesis of this disease.

Bacteria↗
PubMed1991

Possible role of Streptococcus pyogenes in mucocutaneous lymph node syndrome. XI. Immunoelectron microscopic observation of protoplast-like "spherical bodies" detected in peripheral blood of MCLS patients.

Protoplast-like "spherical bodies" averaging 0.5-1.5 microns in diameter and devoid of cell walls were first detected by Ueno et al, in the buffy coat of heparinized venous blood from patients with mucocutaneous lymph node syndrome (MCLS). But the nature of the "bodies" has yet to be clarified because of the absence of convincing evidence pointing to their antigenic characteristics. The present investigations were designed solely to provide a serological identification of the "bodies" by the use of immunoelectron microscopy, with the following results. First, "spherical bodies" bearing a striking resemblance to those observed by the above-mentioned authors were detected in biopsy specimens from challenge sites in mice infected with Streptococcus pyogenes as well as in the buffy coat of peripheral blood from MCLS patients. Second, the "bodies" detected were stained distinctly in both cases by an immunohistochemical technique using, as the primary antibody, a rabbit antiserum raised toward S. pyogenes-derived protoplasts, which was then absorbed with protoplasts from Staphylococcus aureus and Escherichia coli. Third, the absorbed sera were proved to be not faultless, because complete specificity toward protoplasts from S. pyogenes was not attained due to the presence of a large amount of cross-reactive antigens between protoplasts from the immunizing and absorbing strains of bacteria. The implications of these findings are discussed, particularly in relation to the evaluation of the present serological test for the "spherical bodies".

Animals↗
PubMed1991

Interatrial shunt flow profiles in newborn infants: a colour flow and pulsed Doppler echocardiographic study.

Interatrial shunt flow profiles in 36 normal term infants were examined serially by colour flow and pulsed Doppler echocardiographic techniques from within an hour of birth to four or five days after birth. Shunt flow across the foramen ovale was detected in 33 normal infants (92%) within an hour of birth (mean 40 minutes). The occurrence of interatrial shunting decreased with age, but a shunt signal was still detected in 17 infants (47%) on the fourth or fifth day of life, by then the ductus arteriosus had already closed in all the normal infants. The direction of interatrial shunt flow was predominantly left-to-right, but in 64% there was a coexistent small right-to-left shunt in diastole within an hour of birth; by four to five days it was found in 19%. In the six patients with persistent fetal circulation the direction of the interatrial shunt flow was predominantly right-to-left with biphasic peaks in diastole and systole at the early stage of the disease, and the period of right-to-left shunt flow during each cardiac cycle was significantly longer than that in normal infants examined within 1 hour of birth. In all patients the ductus closed before the foramen ovale. At the time of ductal closure in all patients with persistent fetal circulation right-to-left shunt flow was seen during diastole and its period was still prolonged. These findings suggest that interatrial shunting, predominantly left-to-right, is common in normal newborn infants. Evaluation of the characteristics of the interatrial shunt by Doppler echocardiography may be useful for predicting the progress of or improvement in neonates with persistent fetal circulation.

Blood Flow Velocity↗
PubMed1991

[Treatment of 61 patients with acute myelogenous leukemia at first relapse].

Treatment results in the 61 adult patients with AML in first relapse were analyzed to establish a better strategy for this group of patients. These patients received reinduction chemotherapy during 1979-1988. Complete remission (CR) was obtained in 57.4% of the cases, and the probability of survival and remaining in CR at five years was 11.9% and 17.9%, respectively. The longer duration of initial remission was favorable factor for achieving second CR. Type of reinduction regimens which were different from those used in the initial induction phase did not influence the second CR rate. The use of different consolidation regimen appeared to favorably affect the survival and probability of remaining in CR.

Adult↗
PubMed1990

Endoscopic appearance of the colon and small intestine of a patient with hemorrhagic enteric graft-vs.-host disease.

Endoscopic appearance of the gastrointestinal tract of a patient with severe hemorrhagic enteric graft-vs.-host disease (GVHD) is presented. A 29-year-old man with chronic myelogenous leukemia suffered from severe enteric GVHD after allogeneic bone marrow transplantation. Endoscopy showed hemorrhagic ulceration of the upper jejunum, terminal ileum, and colon at the onset of melena. Sections of biopsies were compatible with acute GVHD. Repeat endoscopy showed gradual healing of the lesions after steroid pulse and antilymphocyte globulin therapy, but the patient died of cytomegalovirus pneumonitis 14 months later. Autopsy revealed submucosal fibrosis of the small intestine and colon.

Adult↗
PubMed1990

Biochemical and physical analysis of subcellular membranes in rat parotid gland enlarged by chronic isoproterenol administration.

1. Chronic administration of isoproterenol caused similar alterations of membrane lipid profile in at least two rat parotid subcellular fractions, secretory granular and microsomal. 2. Typical changes in phospholipid classes and fatty-acyl chain groups were an increase of phosphatidylcholine and a decrease of sphingomyelin, and an increase of octadecadienoyl chain and a decrease of eicosatetraenoyl chain, respectively. 3. Electron spin resonance study showed that the isoproterenol-treatment also affected a membrane physical property, which may be through these compositional changes in membrane constituents.

Animals↗
PubMed1990

[Changes in the free fatty acid composition of rat salivary glands induced by chronic administration of isoproterenol].

The major constituent free fatty acid in rat parotid and submandibular glands was palmitic acid (about 40% of the total), followed by saturated and unsaturated fatty acids with 18 carbon atoms and arachidonic acid. The composition was changed by chronic administration of isoproterenol, with an increase of linoleic acid and a decrease of arachidonic acid coinciding with changes in the acyl composition of phospholipids. With respect to the metabolism of unsaturated fatty acids, delta 6-desaturation activity converting linoleic acid to gamma-linolenic acid was detected using [14C]linoleoyl-CoA in the submandibular gland. These results suggest that changes in the acyl composition of phospholipids induced by chronic administration of isoproterenol are in part due to changes in free fatty acid composition and that delta 6-desaturation activity may be involved in the regulation of unsaturated fatty acid composition.

Animals↗
PubMed1990

[A quantitative study of TMJ sounds. 1. A systematization on frequency analysis of clicking sounds].

TMJ clicking sound is a sign worth noticing as prodromal symptoms of TMJ dysfunction. Therefore, a solution of its characteristics is an important matter to grasp the diagnosis of stomatognathic function and progress of the disease. We try to systematize the procedure from picking-up TMJ sound to convertion of frequency and then investigate picking-up method and the measurement apparatus, because we need a quantitation of acoustical components of clicking sound to examine the influence of hearing ability due to TMJ dysfunction. The following were obtained: 1. Low frequency noise is reduced by using headgear with microphone located in a external ear. 2. We pick up continuous 30 TMJ sounds three times in separate days. The waveforms of each set are approximately similar. 3. Each peak frequency and pattern of power spectrum examined three times show high correspondence. 4. The range of maximum peak frequencies in all subjects are from 0 to 0.8 KHz.

Auscultation↗
PubMed1989

Phospholipid metabolism in rat submandibular gland. Positional distribution of fatty acids in phosphatidylcholine and microsomal lysophospholipid acyltransferase systems concerning proliferation.

Rat submandibular gland phosphatidylcholine mainly consisted of the 1-saturated acyl-2-unsaturated acyl type. The high occupancy of unsaturated fatty acid at the C-2 position is in part explained by the preference of microsomal acyl-CoA:1-acyl-sn-glycero-3-phosphocholine (1-acyl-GPC) acyltransferase for unsaturated fatty acyl-CoAs. This enzyme activity was partially inhibited by divalent cations. Ca2+ may be important for regulation of a deacylation-reacylation cycle, suggested because Ca2+ is also known to activate the deacylation enzyme, phospholipase A2. Although the presence of 1-acyl-GPC acyltransferase activity is also observed in plasma membrane of the submandibular gland, the microsomal enzyme showed properties different from the enzyme in plasma membrane in terms of its susceptibility to neural salts and detergents. Cell proliferation caused by chronic administration of isoproterenol resulted in an increase of linoleic acid at the C-2 position of phosphatidylcholine. However, this alteration did not correlate with the changes of activity and substrate specificity of 1-acyl-GPC acyltransferase and the other C-2 acylation enzyme, 1-acyl-sn-glycero-3-phosphate acyltransferase, which suggests that the alteration of fatty acid by isoproterenol treatment is due to a change of supply of substrates or specific acyl breakdown of phosphatidylcholine.

1-Acylglycerophosphocholine O-Acyltransferase↗
PubMed1989

Follow-up after polypectomy of colorectal adenomas. The importance of total colonoscopy.

Five hundred eighty-two patients with colorectal adenomas or early cancers were polypectomized from 1974 to 1985. In 100 patients, total colonoscopy was performed more than twice after the initial polypectomies. These patients were divided into three groups: group A patients underwent total colonoscopy at 1-year intervals; group B patients underwent total colonoscopy at 2-year intervals, group C patients underwent total colonoscopy at 3-year or more than 3-year intervals. The frequency and location of newly developed adenomas were investigated. The detection rate for new adenomas was 13% in group A and 50% in group B; thus, there was a significant difference between group A and group B (P less than 0.01). The transverse colon is the only segment where the topological proportion of newly developed adenomas increased in comparison with that of index adenomas (P less than 0.05). The detection rate for new adenomas was significantly higher in patients who had carcinoma in situ at the time of initial polypectomy (P less than 0.05). Questionnaires about colonoscopy and colonic adenomas were therefore mailed to the patients who were lost to follow-up after the polypectomy.

Colonic Polyps↗
PubMed1989

Comparison of phospholipid N-methylation activity in rat submandibular salivary gland and liver.

Successive phospholipid N-methylation from phosphatidylcholine to phosphatidylethanolamine in submandibular gland and liver microsomes proceeded without the addition of exogenous phospholipid substrate. Methylation activity in the submandibular microsomes showed different susceptibilities to various detergents than the liver enzyme and also partially required Mg2+. However, the three methylation steps could not be distinguished by their Mg2+ requirements. Ca2+ had no effect on the activity. The methylation activity in submandibular gland was much lower than in liver. Chronic administration of isoproterenol, which causes an increase of phosphatidylcholine in membrane phospholipids of salivary glands, decreased methylation activity in the submandibular gland. Thus the increase in phosphatidylcholine in isoproterenol-treated rat salivary glands may not be derived from the phospholipid methylation pathway, but may be due to stimulation of other routes of phosphatidylcholine metabolism.

Animals↗
PubMed1989

An experimental study of spinal cord evoked potentials and histologic changes following spinal cord heating.

To study the safety of hyperthermia cancer treatment, canine spinal cords were heated with radio waves to between 43 C and 47 C for 30 minutes. Spinal cord evoked potentials (SCEP) studied by epidural recording after epidural stimulation showed shortened latency and unchanged amplitude at 44 C or below. At 45 C or above, reduction of amplitude combined with shortened latency was observed, a phenomenon that has not hitherto been reported. After heating to 45 C, SCEP recovered with the reduction of temperature, but histologic examinations showed pigment exudation, vacuolation, and hemorrhage. These results suggest that tolerable spinal cord temperature should not exceed about 44 C.

Animals↗
PubMed1989

Possible role of Streptococcus pyogenes in mucocutaneous lymph node syndrome. VIII. Immunological tolerance to S. pyogenes-associated antigens seems essential to induction of MCLS.

In our previous studies, we attempted to show that new-born mice infected with an attenuated strain of Streptococcus pyogenes, and exposed to streptococcal antigens approximately one month later, failed to develop a humoral response to those antigens but were able to respond normally to other unrelated antigens. Since such immunological characteristics are identical to those of patients with the mucocutaneous lymph node syndrome (MCLS), the present studies were performed with the aim of assessing the antibody-forming activities of peripheral blood lymphocytes collected from MCLS patients. These lymphocytes were cultured in the presence of pokeweed mitogen, streptolysin-O and streptococcal C-polysaccharide, leading to their refractoriness to S. pyogenes-associated antigens coupled with normal responsiveness to unrelated antigens. The implication of such immunological responsiveness elicited from neonatal exposure to streptococcal antigens is discussed, particularly with reference to the induction of MCLS.

Antibody Formation↗
PubMed1989

Possible role of Streptococcus pyogenes in mucocutaneous lymph node syndrome. IX. Quantitation by ELISA of streptococcal pyrogenic exotoxin in the serum of MCLS patients.

In the present paper we describe the use of an enzyme-linked immunosorbent assay reinforced with an introduction of monoclonal antibody, for the detection and quantitation of streptococcal pyrogenic exotoxin (SPE) in the serum of patients with mucocutaneous lymph node syndrome (MCLS). The amount of SPE was usually at a high level, and its 100% incidence in patients' sera was proved whenever the assay was made on the day of admission, thereby showing a marked contrast to carefully matched control sera which failed to mediate any positive result. As for the change in detected amount of the toxin, a clear dichotomy was observed between the serum of gammaglobulin-treated patients and that of infants given aspirin; in the former the positive result turned to negative rapidly following the initiation of treatment coupled with a defervescence, while in the latter the reduction of SPE levels was scarcely monitored for as long as 17 days after the onset of illness. Quantitation of SPE might be an auxiliary test for the diagnosis of MCLS, because a considerable amount of SPE was assessed in a patient who developed characteristic huge coronary artery aneurysms following an illness which did not fulfill the diagnostic criteria. These findings support our speculation in relation to the certain role of S. pyogenes as an etiological agent for MCLS. The possible mechanisms of gammaglobulin treatment in reducing the prevalence of cardiovascular lesions and the duration of systemic inflammation are discussed.

Animals↗
PubMed1989

Responsiveness of the ductus arteriosus to prostaglandin E1 assessed by combined cross sectional and pulsed Doppler echocardiography.

Cross sectional echocardiography combined with Doppler echocardiography was used to record either ductal morphology or the flow profile within the ductus arteriosus before and after infusion of prostaglandin E1 in 25 newborn infants with cyanotic and acyanotic congenital heart disease with ductus dependent blood flow. The ultrasound results were compared with changes in arterial oxygen tension and the overall clinical response to prostaglandin E1 seen during the same period in 24 of the 25 patients in whom the degree of ductal narrowing could be determined with the ultrasound method. At the time of the study, the ductus was widely patent or slightly narrowed in 12 patients and was closed in two patients. These patients did not respond to prostaglandin E1. There was prominent localised narrowing of the ductus in seven patients and generalised narrowing in three. After the infusion of prostaglandin E1 there was no ductal narrowing in these patients, except for one patient who had slight residual localised narrowing. There was also a considerable change in the ductal flow profiles in each patient. In these 10 patients infusion of prostaglandin E1 resulted in an increase in arterial oxygen tension, clinical improvement, or both. The present study indicates that prostaglandin E1 is effective in patients with prominent narrowing of the ductus but is not in patients in whom the ductus is widely patent or closed. Cross sectional echocardiography combined with Doppler echocardiography was useful for predicting the responsiveness of the ductus arteriosus to the infusion.

Alprostadil↗