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Biomedical subjects

K Kurihara

Publications and source records attributed to K Kurihara.

At least 289 records · Page 16Linked to original sources
PubMed1984

Benign fibroblastic tumor-like lesion simulating malignancy in the maxilla.

A benign fibroblastic lesion simulating malignancy is reported. The lesion occurred in the right maxilla of an 11-year-old girl and perforated the outer cortical plate, suggesting malignancy. The biopsy, however, revealed proliferation of fibroblasts and fibrocytes with neither prominent atypia nor mitosis in a myxoid matrix. Electron microscopy showed that some fibroblastic cells were indeed myofibroblasts. As the lesion did not belong to any established entities, the final pathological diagnosis of benign fibroblastic lesion was made, leading to conservative surgery. The patient is well without recurrence 18 months after surgery.

Cell Nucleus↗
PubMed1983

Ion dependence of the eel taste response to amino acids.

The effects of changed ionic environments on the taste responses to amino acids were examined by recording the activity of the palatine nerve. The responses to glycine, L-proline and L-arginine dissolved in deionized water were greatly reduced after ions were removed from the surface of the palatine epithelium by treatment with 5 mM EDTA. The addition of various species of salts to amino acid solutions caused reversible recovery of the responses. The response to 0.1 mM glycine increased with an increase in salt concentration in amino acid solutions and reached saturation level. The effects of salts of divalent cations (CaCl2 and MgCl2) appeared at much lower concentration (10(-7) M) than those of salts of monovalent cations (NaCl and KCl) (10(-4) M), suggesting that cations support the taste response. All the organic cations examined, including those of large molecular weights (choline, Tris, bis-Tris, bis-Tris propane, tetraethylammonium, triethanolamine and D-glucosamine), also supported the taste responses. The results obtained led to a conclusion that not a specific cation but various species of cations can support the eel taste responses. It is suggested that the cations do not act as current carrying ions to depolarize the taste cells but that the binding of the cations to the receptor membrane plays an essential role in taste reception.

Amino Acids↗
PubMed1983

Mechanism of the water response in carp gustatory receptors: independent generation of the water response from the salt response.

The carp gustatory responses to various salts and those to distilled water after adaptation of the receptors to the salts were recorded from the palatine nerve under varying conditions. (a) As far as Na4Fe(CN)6 solution prepared freshly was used, any peak in the dose-response curve was not observed, while the solution stored overnight induced a large peak response at the low concentration region as Konishi reported. The magnitude of the water response after adaptation to the stored solution was practically equal to that after adaptation to the fresh solution, suggesting that the receptor site for the water response is different from that for the dilute salts. (b) The responses to salts depended largely on the species of both cations and anions of the salts. The responses were deceased with an increase in the lyotropic number of the anions and increased with an increase in the number above 11. The response to distilled water was practically independent of the species of both monovalent cations and anions of the salts used for the adaptation. The pH dependence of the response to 10 mM NaCl was largely different from that to distilled water after adaptation to 10 mM NaCl. (c) The water response was suppressed by the presence of electrolytes in stimulating solution; the data obtained with different species of salts were described by a single curve as a function of the ionic strength. (d) The mechanism to explain how distilled water leads to depolarization of the taste cell was discussed in terms of the electric double-layer potential.

Animals↗
PubMed1983

Role of cations in olfactory reception.

The effects of changed ionic environments on the olfactory responses in the carp, the rainbow trout, and the bullfrog were examined by recording the stimulant-induced waves from the olfactory bulb. (a) Application of stimulants (various species of amino acids and beta-ionone) dissolved in deionized water to the EDTA-treated olfactory epithelium of the carp did not induce any response. The addition of various species of salts to the stimulating solution reversibly restored the response. (b) The responses of the carp to L-alanine in the presence of MgCl2 and MgSO4 and those in the presence of KCl and K4Fe(CN)6 are described by single curves, respectively, as a function of concentration of the cations, suggesting that the cations support olfactory reception. (c) All the inorganic cations examined (Li+, NH3+, K+, Ca2+, Mg2+, Co2+, Mn2+, Cd2+) and organic cations (Tris+, choline+, bis-Tris propane2+) were effective to support the response of the carp, whereas TEA+, TBA+, triethanolamine+, and bis-Tris+ were ineffective. (d) The olfactory responses of the rainbow trout and the bullfrog were also reduced by removal of ions from the surface of the epithelia and recovered by addition of ions. (e) It is suggested that the cations do not act as current carriers across the apical olfactory cell membrane for the generation of the receptor potential.

Amino Acids↗
PubMed1983

Extramedullary plasmacytoma associated with a Castleman's lesion of the cervical nodes.

A rare case of extramedullary plasmacytoma seen in a patient with a Castleman's lesion is described. The mass occurred in the cervical nodes of a 61-year-old female patient, and the primary site was the intra- or peri-parotid nodes. The histological examination revealed abnormal characteristic lymph follicles and nodular proliferation of plasma cells in the same lymph nodes. The neoplastic change of plasma cells was studied on the basis of the immunoperoxidase (PAP) method. The patient is well without recurrence 15 months after total resection.

Female↗
PubMed1983

Extramedullary plasmacytoma with crystal inclusions arising from the palatal tonsil.

A case of extramedullary plasmacytoma of the left palatal tonsil in a 51-year-old woman is reported. The histological features of the tumor are typical, except for the appearance of crystal inclusions in plasma cells, histiocytes and matrices. The developmental process and the nature of the crystal inclusions are discussed, based on electron-microscopic findings. The patient has been followed for one year post-operatively, and no clinical evidence of recurrence has been observed.

Crystallography↗
PubMed1983

Voltage-dependent Ca2+ channel and Na+ channel in frog taste cells.

Frog taste cells were hyperpolarized by injecting an inward current pulse, and regenerative anode-break potentials were observed at the termination of the current pulse. The results obtained are as follows. 1) The magnitude of the anode-break potentials increased with the extent of hyperpolarization of taste cells and reached a saturation level around -200 mV. 2) The magnitudes of the anode-break potentials observed in 80 different taste cells hyperpolarized to about -200 mV were distributed widely from cell to cell. The average magnitude was 39 mV. 3) The anode-break potentials were recorded after the lingual artery was perfused with artificial solutions containing various channel blockers. The results indicated that the anode-break potentials are composed of Na+ and Ca2+ components. 4) The slope of the current-voltage relation obtained with cells hyperpolarized to 100 mV was appreciably decreased above -50 mV by application of tetrodotoxin to the perfusing solution. Discussion was made on possible roles of the voltage-dependent Na+ and Ca2+ channels in the electrotonic spreading of the depolarization at the receptor membranes to the synaptic area and in releasing a chemical transmitter.

Animals↗
PubMed1982

Effect of Ca2+, cyclic GMP, and cyclic AMP added to artificial solution perfusing lingual artery on frog gustatory nerve responses.

The lingual artery of the bullfrog was perfused with artificial solution and the effects of Ca2+, Ca-channel blockers (MnCl2 and verapamil), cGMP, and cAMP added to the perfusing solution of the gustatory nerve responses were examined. The responses to chemical stimuli of group 1 (CaCl2, NaCl, distilled water, D-galactose, and L-threonine) applied to the tongue surface were greatly decreased by a decrease in Ca2+ concentration in the perfusing solution, suppressed by the Ca-channel blockers, enhanced by cGMP, and suppressed by cAMP. The responses to chemical stimuli of group 2 (quinine hydrochloride, theophylline, ethanol, and HCl) were practically not affected by a decrease in Ca2+ concentration, the Ca-channel blockers, cGMP, and cAMP. The responses to the stimuli of group 1 seem to be induced by Ca influx into a taste cell that is triggered by depolarization and modulated by the cyclic nucleotides in a taste cell. The responses to group 2 seem to be induced without accompanying Ca influx.

Animals↗
PubMed1982

Pathological characteristics of oral lymphomas.

Nine cases of oral extranodal lymphomas are described. Histologically, 6 cases were histiocytic, 2 lymphocytic and 1 Burkitt's lymphoma. According to the criteria of the Japanese Lymphoma Study Group, 8 cases seemingly belonged to the B-cell lymphoma classification, and one was unclassified. Geographical differences in the distribution of oral extranodal lymphomas between Japan and western countries were surveyed. A review of our cases and those in the literature revealed no significant difference in sex, age, frequency of B-cell lymphomas or site of predilection. In Japan, histiocytic lymphomas were the most common type of extranodal oral lymphomas. The most prevalent type of oral extranodal lymphomas in western countries could not be determined from the literature.

Adult↗
PubMed1982

High sensitivity of Xenopus gustatory receptors to amino acids and bitter substances.

The gustatory nerve responses of the aquatic toad Xenopus laevis to salts, acids, amino acids, and bitter substances were recorded. 1) The gustatory receptors were sensitive to amino acids and bitter substances. The thresholds were 10(-7) M for Arg, 3 X 10(-9) M for strychnine, and 3 X 10(-8) M for quinine, 200-20,000 times lower than the thresholds for the respective stimuli in the bullfrog. 2) The basic and the neutral amino acids were effective whereas the acidic ones were not. Relations between the responses and log stimulus concentrations for the basic amino acids were linear in a wide concentration range whereas those for the neutral ones were of S shape. Cross-adaptation did not occur among pairs of a basic amino acid and a neutral one. 3) Responses to the basic amino acids and the basic bitter substances were suppressed by the addition of salts to the stimulating solutions, while those to the neutral and the acidic substances were not suppressed.

Amino Acids↗
PubMed1982

[Studies on cerebral scavenger cells (fluorescent granular perithelial cells) - especially uptake and digestion of incorporated fat].

Small cerebral vessels including capillaries are provided with the specific barrier (blood brain barrier) for a transport of substances from blood to cerebral tissue. However, it is also established that fat soluble substances are easily permeable in this barrier. Along cerebral small vessels, the cells having intracellular fluorescent granules are distributed and named "fluorescent granular perithelia (F.G.P.)" by the authors. They are potent in the uptake capacity for exogenous substances as reported in the previous papers. In this study, 24 male Wistar rats aged 8 months and 2.5 years old were employed. They were fed with a fat rich chow (Oriental Co.) containing 10% lard, 2% cholesterol and methylthiouracil for one day and fifteen days. Half of them was subcutaneously injected with 5 mg/kg of elastase (Eisai Co.) dissolved in physiological saline once a day. To clarify the effect of elastase on fat incorporated by F.G.P., 4 rats aged 2.5 years were fed with a fat rich chow for 2 days. After then, they were fed with ordinal rat chow for 3 days with or without elastase injection. After decapitation, cerebral cortex of rats was removed in cold physiological saline and sliced with a blade. Half of the sliced specimens was prepared by the authors' method (Mato and Ookawara, 1979) and stained with hematoxylin eosin, periodic acid Schiff reaction and sudan black B for a light microscopical observation. The other half of the specimens was immersed in a mixture containing 2% paraformaldehyde and 2.5% glutaraldehyde buffered with 0.1M phosphate solution (pH 7.4) for 10 h. The specimens were then postfixed with osmium tetroxide buffered with the same solution for 2h. The other procedures for embedding and cutting were the same as in a routine method. Following findings were obtained at the light and electron microscopical levels; when they were fed with a fat rich chow, fat in blood passed through vascular walls and was taken up by F.G.P.. The quantity of fatty deposits in F.G.P. was different depending on age of rats employed for the experiment. The deposits in F.G.P. increased with advancing of age. That is, in old rats a lot of deposits were chiefly distributed in inclusion bodies at one and fifteen days after the administration. The difference in quantity of deposits between young and old rats was not only based on the permeability of vessels, but on the digestion capacity of F.G.P. for fat. On the other hand, Elastase, a specific enzyme for lysis and synthesis of elastic components, prepared by Eisai Co., made a suppressive effect to the permeability of cerebral small vessels and facilitated markedly the digestion capacity of F.G.P. for fat, although the mechanism remained unsettled. From this standpoint, F.G.P. are also designated as "cerebral scavenger cells".

Animals↗