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Biomedical subjects

K Kurihara

Publications and source records attributed to K Kurihara.

At least 19 recordsLinked to original sources
PubMed1992

Interleukin-5 selectively enhances the chemotactic response of eosinophils obtained from normal but not eosinophilic subjects.

We have attempted to determine whether interleukin-5 (IL-5), a cytokine that selectively affects eosinophil (as opposed to neutrophil) differentiation and activation, also modulates eosinophil migrational responses. Using a modified Boyden chemotaxis assay, IL-5, IL-3, and granulocyte-macrophage colony-stimulating factor (GM-CSF) gave a weak locomotory response for eosinophils from normal nonatopic subjects (optimal at 10(-11), 10(-8), and 10(-9) mol/L, respectively), but not for eosinophils from subjects with an eosinophilia associated with asthma and/or allergic rhinitis. In contrast, IL-5 and IL-3 had no effect on neutrophils, while GM-CSF was chemotactic for neutrophils over a limited concentration range, optimal at 10(-8) mol/L. When eosinophils from normal subjects were incubated with IL-5 (10(-9) mol/L), the locomotory response to platelet-activating factor (PAF; 10(-8) mol/L, P less than .05), leukotriene B4 (LTB4; 10(-6) mol/L, P less than .01), and N-formyl-methionyl-leucyl-phenylalanine (FMLP; 10(-8) mol/L, P less than .01) was significantly enhanced. The percentage enhancement of eosinophil locomotion by IL-5 was greater for eosinophils from normal as compared with subjects with an eosinophilia associated with asthma (P less than .05 for PAF and LTB4; P less than .01 for FMLP). Preincubation of eosinophils from normal subjects with IL-5 (10(-9) mol/L) attenuated the subsequent locomotory response to IL-5 (10(-12) and 10(-11) mol/L, P less than .05). Therefore, the observed refractoriness of eosinophils from eosinophilic subjects to both directional migratory and priming effects of IL-5 in vitro, may reflect a deactivation process resulting from prior exposure in vivo. The selective priming of eosinophil but not neutrophil locomotion by IL-5 suggests that this cytokine may play a significant role in the preferential accumulation of eosinophils at sites of allergic inflammation.

Asthma↗
PubMed1992

Desmoplastic malignant melanoma of the gingiva.

A case of desmoplastic melanoma in a 58-year-old man is reported. This rare malignancy occurred in the maxillary alveolus, appearing as an epulis. Histologically, the tumor was flanked by melanocytic proliferation in the adjacent mucosae. At the time of local recurrence after partial maxillectomy, the tumor showed a polypoid growth, with an increase in cellularity and mitotic rate resembling spindle cell carcinoma. The value of immunostaining for diagnosis is stressed.

Humans↗
PubMed1992

Cranial fasciitis of childhood: a case report.

Cranial fasciitis of childhood is very rare, only 17 cases having been reported in the literature. We report an additional case of this rare disease. The patient was a 5-year-old boy who complained of left exophthalmos and double vision. Computed tomography (CT) and magnetic resonance imaging (MRI) revealed a large epidural mass in the left frontal region that had invaded into the underlying anterior skull base. The tumor showed homogeneous, low density with nonhomogeneous contrast enhancement on the CT scans, and low intensity on the T1-weighted and high intensity on the T2-weighted MRI images. A whitish-pink, elastic, hard tumor was revealed in the epidural space in the left anterior cranial fossa, which was totally excised with curettage of the affected anterior skull base. The origin of the tumor was suspected to be the fibrous connective tissue of the sphenofrontal suture. The histological diagnosis was that of cranial fasciitis. There was no evidence of recurrence 1 year postoperatively.

Child, Preschool↗
PubMed1992

Epithelial hyperplasia of the breast. Comparison of incidence between cases of breast carcinoma and control autopsy specimens with immunohistochemical observation of blood group antigens.

Epithelial hyperplasia in the duct, ductule or lobule of the breast is a very common lesion and has been considered to carry a risk of subsequent invasive carcinoma. However, it is not known whether epithelial hyperplasia can transform into carcinoma or whether malignant change occurs de novo. We analyzed the incidence of epithelial hyperplasia of the breast by making a comparison between cases of breast carcinoma and control autopsy specimens, and studied differences in the membrane antigens of the constituent cells using immunohistochemical staining of blood group antigens. It was found that the frequency of epithelial hyperplasia was higher in the cases of breast carcinoma. The lesions showed loss of A, B and H antigens at high frequency, and the proportion of lesions showing loss of these antigens became higher as the atypia of the lesion increased. On the other hand, expression of Lea antigen was observed more frequently in atypical epithelial hyperplasia or in situ carcinoma than in ordinary epithelial hyperplasia. These findings suggest possible transformation from epithelial hyperplasia to carcinoma, and indicate that atypical epithelial hyperplasia may be precancerous in nature.

Adolescent↗
PubMed1992

P2 purinergic receptors and cellular calcium metabolism in A 431 human epidermoid carcinoma cells.

Stimulation of P2 purinergic receptors on A 431 human epidermoid cells with ATP rapidly mobilized intracellular calcium and increased cytosolic free Ca2+ ([Ca2+]i). Incorporation of 45Ca2+ was also stimulated by ATP at a rate less than that of [Ca2+]i elevation. Among a number of nucleosides, nucleotides, and their analogues examined, ATP, GTP, UTP, ADP, UDP, adenosine 5'-O-(3-thiotriphosphate) (ATP gamma S), and 5'-adenylylimidodiphosphate (AMP-PNP) increased both [Ca2+]i and 45Ca2+ influx, whereas others did not; these latter two analogues (ATP gamma S and AMP-PNP) blocked the ATP-stimulated 45Ca2+ influx only very slightly, suggesting that they are not prominent antagonists but rather agonists. A high correlation between [Ca2+]i increase and 45Ca2+ influx, in terms of nucleotide specificity, suggests the involvement of [Ca2+]i in influx of 45Ca2+. It appeared that [Ca2+]i elevated by several nucleotides or nucleotide analogues opened a calcium gate, thus allowing the influx of 45Ca2+. P2 purinergic receptors on these cells had such a characteristic that they were rapidly desensitized. These nucleotides or analogues also affected epidermal growth factor (EGF) receptors by inhibiting the EGF binding. The differences of ligand or substrate specificities between P2 purinergic receptors and ecto-nucleotidases indicates that the two components are different molecules involved in different systems.

Calcium↗
PubMed1992

Quantitative analysis on odor intensity and quality of optical isomers in turtle olfactory system.

No systematic electrophysiological study on differences in odor intensity and quality between optical isomers has been carried out. In the present study, we measured the turtle olfactory bulbar responses to six pairs of highly pure optical isomers and compared the differences in odor intensity and quality between the optical isomers. The results obtained indicated that with all odorants tested, there was no difference in odor threshold and intensity in the whole concentration range examined between optical isomers. The difference in odor quality of optical isomers was evaluated by a quantitative cross-adaptation method in which odorant concentration was varied. The degree of cross adaptation between optical isomers greatly varied with species of odorants. The rank order of the magnitude of the differences in odor quality between optical isomers was carvone greater than beta-citronellol greater than menthol greater than hydroxycitronellal greater than citronellal greater than limonene.

Adaptation, Physiological↗
PubMed1992

Characterization of ecto-nucleoside triphosphatase on A-431 human epidermoidal carcinoma cells.

Hydrolysis of extracellular ATP and other nucleoside phosphates by A-431 human epidermoidal carcinoma cells was studied. The hydrolysis of extracellular ATP by these cells required either Mg2+ or Ca2+, and either cation could be replaced by Co2+, Fe2+, or Mn2+. Nucleoside triphosphates (ATP, GTP, CTP, UTP, and dTTP), but not nucleoside diphosphates, were hydrolyzed by the cells with Km and Vmax values similar to those for ATP (0.9-1.1 mmol/l and 6-10 nmol Pi formed/10(6) cells, respectively). The hydrolysis of ATP was inhibited strongly by ATP-gamma S and AMPPNP, and weakly by AMPCPP and ADP-beta S, but not by AMPCPP or AMPCP. Since the hydrolysis of [gamma-32P]ATP was inhibited by all these nucleoside triphosphates, the binding site for ATP is presumed to be the same as that for the other nucleoside triphosphates. All these results indicate that ecto-ATPase activity associated with A-431 cells is due to ecto-nucleoside triphosphatase. The nucleotide specificity shown in the present study indicates that ecto-nucleoside triphosphatase associated with A-431 cells is a molecule different from P2-purinergic receptors which can be stimulated specifically with nucleoside phosphates like ATP, ADP, UTP, UDP, and GTP, but not by other nucleotides.

Adenosine Diphosphate↗
PubMed1992

A case of homicidal choking mistaken for suicide.

This report presents an autopsy case of the homicidal choking of an adult, who died as a result of tissue paper being thrust into his mouth. An in-patient (a 29-year-old Japanese man) at a mental hospital was choked to death by another male in-patient, his roommate, who thrust a large amount of tissue paper into his mouth after rendering him slightly unconscious by cervical compression. At the time of discovery, this mental patient was believed to have committed suicide by inserting tissue paper into his own mouth. Autopsy findings and re-investigation of the case revealed that the subject had been murdered. This is a very rare case of choking used as a method of homicide.

Adult↗
PubMed1992

[Inversion of chromosome 16 observed in acute myeloblastic leukemia (M2) with biphenotypic surface markers lacking monocytosis and eosinophilia].

Inversion of chromosome 16 was found in a 73-year-old female with acute myeloblastic leukemia (FAB:M2). Complete remission was achieved by combined chemotherapy (DNR, Ara-C, 6-MP, Prednisolone), but she relapsed 6 months later without CNS involvement and died of respiratory failure presumably due to cerebrovascular accident during remission reinduction chemotherapy. Biphenotypic surface markers (CD2+ and CD13+) were observed on relapse. Eosinophilia was not observed throughout. Our patient and the other reported case suggest that biphenotypism and the lack of eosinophilia and monocytosis in inv (16) leukemia may be correlated with a poor prognosis.

Aged↗
PubMed1992

Convulsions in senescence-accelerated mice (SAM-R/1/Eis).

Senescence-accelerated mice (SAM) are one of the animal models used for studying senescence, which consist of several substrains such as SAM-R/1, R/2, P/1, P/2. SAM-R/1/Eis maintained in Eisai Tsukuba Research Laboratories, Ibaraki, Japan, was originally introduced as a substrain of a normal control SAM-R/1 from Kyoto University, Japan. We have noted signs of convulsions in SAM-R/1/Eis mice during routine animal care, particularly while changing cages. We identified the clinical signs and determined the concentrations of glucose and immunoreactive insulin in plasma of SAM-R/1/Eis mice. There were no differences in the male:female ratios of mice showing prodrome only, grand mal, or no-signs. The ages at which prodrome and grand mal were first noted peaked between 20 and 25 weeks. Concentrations of glucose and immunoreactive insulin in plasma did not indicate the mice were in insulin hypoglycemia, which is one cause of convulsions. AKR strain mice, some of which originated with the SAM strain are known to become convulsive by repeated "throwing" stimulations. Conversely, in SAM-R/1/Eis, throwing stimuli are not needed to cause convulsive signs. Thus it is likely that in SAM-R/1/Eis mice the signs are triggered by repeating mild environmental changes, such as changing cages. The results of this study show that SAM-R/1/Eis is neither a normal control strain, nor an original SAM-R/1 strain. But it is possible that SAM-R/1/Eis is another useful animal model for studying spontaneous convulsion.

Aging↗
PubMed1992

Serological and biochemical studies on En(a-) human erythrocytes in a Japanese family.

The propositus erythrocytes with phenotype En(a-), which was found in the first example of a Japanese family, reacted with anti-N serum weaker than the ordinary phenotype N erythrocytes. When the erythrocyte membranes of the propositus were subjected to SDS-PAGE, no glycophorin A was observed on the gel by PAS staining, whereas glycophorin B band was observed. The S and the s antigens of the propositus erythrocytes were appeared to be normal. These results suggested that N activity of the propositus erythrocytes may be derived from glycophorin B components on the erythrocyte membranes. The amounts of bound sialic acid of the erythrocyte membranes were significantly lower in the En(a-) erythrocytes than the ordinary OMN erythrocytes. Neither the OMN nor the En(a-) erythrocytes showed the agglutinability to Arachis hypogaea lectin. The number of lectin receptor sites on the En(a-) erythrocyte membranes was significantly lower than on the OMN erythrocyte membranes for Limulus polyphemus, Triticum vurgaris and Bauhinia purpurea lectins. These results provide further support for the contention that En(a-) cells lack the glycophorin A as major erythrocytes sialoglycoprotein on the membranes.

Asian People↗
PubMed1992

[Right-sided patent ductus arteriosus with a right aortic arch and right descending aorta].

We experienced an extremely rare anomaly, i.e. right-sided persistent ductus arteriosus with a right aortic arch and right descending aorta. Reviewing the literature, we found only two cases clinically reported in Japan as far as we know. The diagnosis was established by angiography and MRI. We treated the patient successfully through right thoracotomy.

Aorta, Thoracic↗
PubMed1992

[Basic research into the measurement of eosinophil cationic protein (ECP) in blood samples].

Eosinophil cationic protein (ECP), which is one of the eosinophil granule proteins, can now be measured with a radioimmunoassay kit. However, the level of ECP in blood samples is affected by the method of treatment of the samples. We investigated the effect on ECP level of a variety of treatment methods to establish the fundamental condition for the measurement of ECP level in blood samples. ECP levels in serum or heparin plasma increased time-dependently until 2 hr. This increase was considered to be due to active in vitro release of ECP from eosinophils. Serum ECP level at 1 hr was temperature-dependent, being higher at 37 degrees C than at 25 degrees C. On the other hand, ECP level in EDTA plasma did not change significantly during a 3 hr period, and this level of ECP was considered to be that which had been released into the blood in vivo. ECP levels were always in the order of serum greater than heparin plasma greater than EDTA plasma. Though there was a positive correlation between serum ECP level and peripheral blood eosinophil count, the degree of correlation was not strong (r = 0.46, 6, 0.05 greater than p less than 0.01). This suggests that the serum level of ECP, or the "releasibility" of ECP from eosinophils, may reflect the activation of eosinophils.

Blood Proteins↗
PubMed1991

Liposomes having high sensitivity to odorants.

The conditions to increase the sensitivities of liposomes to odorants were examined. The results obtained are as follows. (1) The minimum concentration of amyl acetate to induce the membrane potential changes (threshold) in phosphatidylcholine (PC) liposomes was about 10(-4) M and addition of 10 or 20% phosphatidylserine (PS) lowered the threshold to about 10(-9) M, which was lower than the thresholds for amyl acetate in the turtle and frog olfactory systems. (2) Similar to amyl acetate, addition of PS to PC greatly lowered the threshold for beta-ionone. On the other hand, addition of PS to PC in certain ratio increased the threshold for citral, suggesting that addition of PS to PC does not always increase the responses to all odorants. (3) The membrane fluidity change of the liposomes in response to odorants occurred at similar concentration region where the membrane potential changes occurred. The presence of CaCl2 in external solution much greatly increased both the magnitude of the membrane potential changes and the membrane fluidity changes of the PC-PS liposomes in response to amyl acetate than the presence of NaCl and MgCl2. These results suggest that the membrane fluidity change is related to generation of the membrane potential change. (4) It was estimated that adsorption of less than a few molecules of amyl acetate on single liposome elicits detectable changes in the membrane potential and the membrane fluidity.

Benzothiazoles↗
PubMed1991

Canine taste nerve responses to monosodium glutamate and disodium guanylate: differentiation between umami and salt components with amiloride.

It has been argued whether the 'umami substances' such as monosodium glutamate (MSG) and disodium 5'-guanylate (GMP) stimulate the salt receptor or the unique receptor to the umami substances. We examined effects of amiloride, which inhibited the canine chorda tympani nerve responses to salts such as NaCl, KCl and NH4Cl, in a competitive manner, on the nerve responses to the umami substances and differentiated between the umami and salt components. Amiloride shifted the dose-response curves for MSG to a higher concentration region, suggesting that amiloride inhibits the response to MSG in a competitive manner. The response to GMP alone and that induced by synergism between relatively low concentrations of MSG and GMP were not inhibited by amiloride. These results suggested that the response to MSG alone is the salt response and the response to GMP alone or that induced by the synergism is the umami response. The presence of MSG shifted the dose-response curves for GMP to a lower concentration region, suggesting that MSG increases the affinity of GMP to umami receptors. The present results favor the conclusion that GMP acts as an agonist and MSG acts as a modulator for the umami receptor in the dog. The synergism can be explained by an allosteric model where the umami receptor is assumed to have two binding sites, one for GMP and another for MSG.

Amiloride↗
PubMed1991

Canine taste nerve responses to umami substances.

The taste responses to the "umami substances" such as monosodium glutamate (MSG), guanosine 5'-monophosphate (GMP) and inosine 5'-monophosphate (IMP) were recorded from the canine chorda tympani nerve. A large synergism was observed between MSG and the nucleotides in most mongrel dogs (type A dog). The extent of the synergism between MSG and the nucleotides was much larger than that observed in any other animal examined except for humans. No synergism was observed between the nucleotide (GMP) and stimuli other than MSG, such as NaCl, HCl, sucrose, quinine, and glycine. It was concluded that the dog is a suitable experimental animal for studies on the responses to umami substances. In order to differentiate umami and salt components in the responses to umami substances, effects of amiloride on the responses were examined. Amiloride inhibited the response to MSG, but did not inhibit the response to GMP alone or those induced by synergism between GMP and MSG. The present results favor a conclusion that GMP acts as an agonist and MSG acts as a modulator for the umami receptor in the dog. The synergism can be explained by an allosteric model where the umami receptor is assumed to have two binding sites, one for GMP and another for MSG.

Amiloride↗
PubMed1991

Rat taste nerve responses to salts carrying cations of large molecular size; are the taste responses to the salts induced by cation transport across apical membranes of taste cells?

1. The responses of rat chorda tympani nerve to various salts carrying cations of large molecular size which have small permeability were measured. 2. Salts carrying polyvalent cations such as Fe3+ or La3+ elicited much larger responses than NaCl or KCl. 3. Ammonium chloride derivatives having methyl or ethyl groups and salts carrying other organic cations of large molecular size elicited the responses comparable to that induced by NH4Cl or NaCl. 4. It was suggested that the taste responses to the salts carrying the cations of large molecular size are induced not by the cation transport but by adsorption of the cations on the membranes.

Animals↗