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Biomedical subjects

K Kurihara

Publications and source records attributed to K Kurihara.

At least 217 records · Page 12Linked to original sources

[Orofacial lymphomas in seropositive patients manifesting the type I human lymphotropic virus (HTLV-I)].

Eleven cases of extranodal orofacial lymphomas (EOFL), consisting of 4 HTLV related and 7 HTLV unrelated EOFLs, have been investigated with regard to their immunohistological and clinical features. The HTLV related EOFLs were found to be of the T-cell phenotype and were associated with a poorer prognosis than the HTLV unrelated EOFLs, most of which were of B-cell origin. The comparatively high incidence of T-cell type in our series was considered to be related to the high percentage of HTLV carriers in our district, an area in which adult T-cell leukemia lymphoma has been found to be endemic.

Adult↗

[A case of local recurrent breast cancer with complete response to combination of systemic chemotherapy and topical use of adriamycin ointment].

A Case of local recurrent breast cancer in a 45-year-old female with complete response to Combination of chemotherapy and topical administration of Adriamycin is reported. The patient had left mastectomy for breast cancer in 1978, and then right mastectomy for breast cancer in 1987. Two years later, she was readmitted to our hospital with right neck lymph node metastasis and local recurrence at right chest wall. Neck lymph node metastasis was treated with irradiation with good response. On the other hand, Adriamycin ointment was applied to recurrent cancer on the right chest. The cancer was gradually diminished in size. Seventy-eight days after treatment, the local chest wall with cancer was resected. Histologically, the entire resected tissue showed no viable cancer cells and Adriamycin concentration in the tissue was extraordinary high (ten to forty fold over on systemic chemotherapy). Adriamycin ointment may be an alternative treatment of choice for local recurrent breast cancer.

Administration, Topical↗

[Dysphagia in olivopontocerebellar atrophy].

Clinical, radiological and manometric studies on thirteen patients with olivopontocerebellar atrophy were performed in order to investigate the characteristics of dysphagia. As a clinical study, a detailed history of dysphagia was taken to distinguish two types of dysphagia, that is to say swallowing disturbance in a narrow sense and passage disturbance. In the radiological study, each phase of swallowing was observed by X-rays with contrast medium (Dionosil). In the manometric study, intraluminal resting pressure in the esophagus and pressure of esophageal contraction after swallowing were measured. The results were as follows: Eight patients had the sensation of swallowing disturbance in a narrow sense and five patients has the feeling of passage disturbance. In X-ray studies four patients had pooling in piriformis sinus and six patients had slight dilatation of the lower esophagus. In manometric studies, six patients had low intraluminal resting pressure of the upper esophageal sphincter, but almost all patients had normal intraluminal resting pressure throughout the esophagus and in the lower esophageal sphincter. Two patients, who had suffered for five and seven years, had loss of both negative and positive wave in the upper esophageal sphincter after swallowing. Another three patients, who had suffered for two, six and seven years, respectively had loss of negative wave in the upper esophageal sphincter after swallowing. Regarding peristaltic wave, eight patients had low amplitude of the wave. Two patients, who had suffered for five and six years, had diphasic shape of the wave. One patient, who had suffered for nine years, had synchronous wave. Nine patients had loss of negative wave in the lower esophageal sphincter.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Cholinergic differentiation of clonal rat pheochromocytoma cells (PC12) induced by retinoic acid: increase of choline acetyltransferase activity and decrease of tyrosine hydroxylase activity.

The effects of retinoic acid (RA), a naturally occurring metabolite of vitamin A, on the growth, morphology and neurochemical differentiation of the PC12 clone of rat pheochromocytoma cells were investigated. RA added to the medium inhibited the growth of PC12 cells in a dose-dependent manner up to 10 microM without affecting their morphology. In PC12 cells cultured in the presence of 10 microM RA for 8 days, the specific activity of choline acetyltransferase (ChAT) was increased 2-fold, while the specific activity of tyrosine hydroxylase (TH) was decreased 0.5-fold compared with cells cultured in the absence of RA. Specific activities of acetylcholinesterase (AChE), glutamate decarboxylase (GAD) and lactate dehydrogenase (LDH) were not affected by RA. Both the increase of ChAT and the decrease of TH induced by RA exhibited similar time and dose dependencies. RA inhibited the increase of TH activity induced by nerve growth factor (NGF), an adrenergic neuronotrophic factor on PC12 cells. From these observations it was concluded that RA induces a cholinergic neurochemical differentiation of PC12 cells independent of a morphological differentiation.

Animals↗

Possible involvements of intracellular Ca2+ and Ca2+ -dependent protein phosphorylation in cholinergic differentiation of clonal rat pheochromocytoma cells (PC12) induced by glioma-conditioned medium and retinoic acid.

It is known that nerve growth factor (NGF) induces neurite outgrowth and elevation of the activity of adrenergic marker enzyme, tyrosine hydroxylase (TH) in clonal rat pheochromocytoma cells (PC12), whereas glioma-conditioned medium (GCM) induces neurite outgrowth and elevation of the activity of cholinergic marker enzyme, choline acetyltransferase (ChAT) in PC12 cells. In the previous study we have shown that retinoic acid (RA) induces specific elevation of ChAT activity and depression of TH activity without morphological differentiation (Matsuoka, I. et al., Brain Res., 502 (1989]. In the present study, we compared the effects of NGF, GCM and RA on the intracellular signalings in PC12 cells in relation to the mechanism of cholinergic differentiation. Addition of NGF, GCM or RA to the culture medium of PC12 cells caused a rapid rise in intracellular Ca2+ concentration [( Ca2+]i) reaching the level of almost 2.5-fold the resting condition within 3-18 h. Thereafter, [Ca2+]i of NGF-treated cells were decreased to the resting level within 12 h. On the other hand, [Ca2+]i of GCM-and RA-treated cells decreased to a level which was 1.8- to 2-fold the resting condition within 24-48 h and stayed at this level for up to 4-7 days. When homogenates of GCM- and RA-treated PC12 cells were incubated with [gamma-32P]ATP, phosphorylation of a protein with molecular mass of 27 kDa (27 K-protein) was specifically enhanced. The phosphorylation of the 27 K-protein was not seen in the homogenate of the NGF-treated cells. The phosphorylation of the 27 K-protein was dependent on Ca2+ and inhibited by inhibitors of Ca2+-dependent protein kinase, H-7 and W-7. Addition of H-7 and W-7 to the culture medium of PC12 cells abolished the elevation of ChAT activity specifically induced by GCM and RA. These observations suggested that the sustained increase of [Ca2+]i and Ca2+-dependent protein phosphorylation are involved in the intracellular signaling mechanism required for the cholinergic differentiation of PC12 cells induced by GCM and RA.

Animals↗

Similarity of ion dependence of odorant responses between lipid bilayer and olfactory system.

In a previous paper (Nomura and Kurihara (1987) Biochemistry 26, 6135-6140), we demonstrated that the lipid bilayer membranes exhibit membrane potential changes in response to various odorants similarly to olfactory cells. The present study demonstrated that ion dependence of the responses of the lipid membranes to odorants is related to that in the carp olfactory system in the following point. (1) The responses to odorants diminished at low concentrations of salts and recovered upon addition of salts to stimulating solutions. (2) Divalent cations were effective in supporting the responses to odorants at much lower concentrations that monovalent cations. (3) Impermeable organic cations were effective in supporting the responses. The present results suggest that the initial process of generation of the receptor potential in olfactory cells resembles that in the lipid membranes.

Lipid Bilayers↗

Mechanism of the water response in frog gustation: possible significance of surface potential.

The frog taste response to deionized water (water response) after adaptation of the tongue to salts was recorded from the glossopharyngeal nerve under various conditions. It was found that the frog water response exhibits different behavior from the carp water response examined in a previous paper13. (a) The frog water response did not decline during stimulation and lasted for at least 3 min, while the carp water response declined within 10 s after stimulation to a spontaneous level. (b) The frog water response was practically independent of species and concentrations of salts in adapting solutions when the tongue was adapted to salts of monovalent cations, while the carp water response was highly dependent of salt concentration in adapting solution. (c) The water response was increased with an increase of CaCl2 concentration in adapting solution, while it was decreased with an increase of MgCl2 concentration. (d) 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. (e) The mechanism of the frog water response together with the carp water response was explained in terms of the surface potential.

Action Potentials↗

ADP-ribosylation of 24-26-kDa GTP-binding proteins localized in neuronal and non-neuronal cells by botulinum neurotoxin D.

Clostridium botulinum D (strain South Africa) produces ADP-ribosyltransferase which modifies eukaryotic 24-26-kDa proteins. ADP-ribosyltransferase activity was associated with a neurotoxin of 150 kDa (Dsa toxin) as confirmed by the elution profile of Dsa toxin from high performance anion-exchange column. The 24-kDa substrate of Dsa toxin-catalyzed ADP-ribosylation was detected in several tissues examined including rat brain, heart, and liver; bovine adrenal medulla; sea urchin eggs; electric organs of electric fish; and cell lines of neural (N18, N1E115, NS20Y, NG108, PC12, and C6) and non-neural (3T3) origins, suggesting its ubiquitous localization in eukaryotic cells. On the other hand, the 26-kDa substrate was detected only in membrane fractions of neural tissues and neuronal cells, suggesting its specific localization in membrane of nerve terminals. ADP-ribosylation of both the 24-kDa substrate in PC12 membrane and the 24-26-kDa substrates in rat brain membrane was potentiated by either divalent cations or guanine nucleotides, whereas adenine nucleotides did not affect the ADP-ribosylation reaction. Trypsin digestion of the 24-kDa substrate in PC12 membrane and the 24-26-kDa substrates in rat brain membrane extract produced different tryptic fragments indicative of the structural difference between the 24- and 26-kDa substrates. Both the 24- and 26-kDa substrates were less sensitive to trypsin digestion before being ADP-ribosylated by Dsa toxin than after, suggesting the conformational alterations of the 24-26-kDa proteins induced by ADP-ribosylation. These results suggest that Dsa toxin modifies two distinct low molecular mass GTP-binding proteins by ADP-ribosylation to alter their putative function(s).

ADP Ribose Transferases↗

Inward rectifier produced by Xenopus oocytes injected with mRNA extracted from carp olfactory epithelium.

Ionic channels encoded by mRNA extracted from carp olfactory epithelium were investigated by injection into Xenopus laevis oocytes. The oocytes expressed an inward rectifier K+ -channel, as detected under two-electrode voltage clamp conditions. The results were as follows. An inactivating inward current appeared on hyperpolarization and increased with increasing extracellular K+ concentrations. The 0 current potentials plotted as a function of log [K+]0 in the range between 2 to 20 mMK+ fell on a straight line, with a slope of 58 mV per tenfold change in K+ concentration, indicating that the current carrier is K+. Chord conductances reached saturation levels on extreme hyperpolarization. The chord conductances at the saturation levels were 35.7, 22.5, and 13.4 muSec in 20, 10, and 5 mM extracellular K+, respectively. Extracellular application of 0.1 mM Cs+ or 0.1 mM Ba2+ blocked the inward current in 2 mM K+, whereas 1 microM TTX or 0.3 mM Cd2+ did not affect the inward current. Inactivation of the inward currents, which became clear on extreme hyperpolarization, was suppressed with decreasing extracellular Na+ concentration. The present results suggest that carp olfactory epithelium is rich in the inward rectifier and is an excellent source of mRNA for cloning cDNA coding the inward rectifier.

Animals↗

Inhibition of platelet-activating factor (PAF)-induced chemotaxis and PAF binding to human eosinophils and neutrophils by the specific ginkgolide-derived PAF antagonist, BN 52021.

We have investigated the effects of BN 52021 (a specific PAF antagonist derived from Ginkgo biloba) on PAF-induced human eosinophil and neutrophil chemotaxis. In response to an optimal concentration of PAF (10(-6) mol/L), the drug was significantly more potent (p less than 0.001) in inhibiting eosinophil as compared to neutrophil locomotion. These inhibitory effects were observed in a dose-dependent manner with a concentration of drug required to produce 50% inhibition of 7.0 (+/- 2.2) X 10(-6) mol/L and 2.3 (+/- 0.2) X 10(-5) mol/L for eosinophils and neutrophils, respectively. Sodium cromoglycate, nedocromil sodium, salbutamol, and dexamethasone (preincubated with cells up to 6 hours) had no effect over a wide dose range (10(-3) to 10(-9) mol/L). BN 52021 was significantly more effective in inhibiting chemotaxis when the cells were preincubated with the compound for up to 1 hour before commencement of the locomotion assay, whereas washing the cells completely abolished this effect. Inhibition by BN 52021 was specific for PAF in that it had no effect on chemotaxis induced by either leukotriene B4, N-formyl-methionyl-leucyl-phenylalanine, or a purified human mononuclear cell-derived neutrophil chemotactic factor. BN 52021 also inhibited the specific binding of [3H]-PAF (10(-8) mol/L) to eosinophils and neutrophils in a concentration-dependent fashion with a concentration of drug required to produce 50% inhibition of 1.5 (+/- 0.3) X 10(-6) mol/L and 9.1 (+/- 2.5) X 10(-7) mol/L, respectively. These results suggest that BN 52021 has potential as an anti-inflammatory agent in conditions associated with PAF-induced accumulation of neutrophils and eosinophils.

Albuterol↗

Acute aortic dissection due to giant cell arteritis. Report of two autopsy cases.

Two autopsy cases of giant cell arteritis with aortic dissection are reported. One patient was an 87-year-old man, and the other was an 80-year-old woman. In both cases the patient died suddenly, and fatal pericardial bleeding due to the aortic dissection was revealed at autopsy. Histologically, marked inflammation with giant cells was observed in the wall of the aorta and in other arteries including the cranial arteries. The authors therefore consider that giant cell arteritis was one of the preceding lesions that culminated in aortic dissection.

Aged↗

T lymphocytes in allergen-induced late-phase reactions and asthma.

We have studied a number of aspects of the interrelationship between T lymphocytes and allergic inflammation. Using monoclonal antibodies and immunocytochemistry we have observed significant infiltration by CD3+/CD4+ T lymphocytes together with evidence of T cell activation in the allergen-induced late-phase skin reaction in human atopic subjects. These changes were accompanied by eosinophil infiltration and activation. Activated T cells were also detected in the blood of patients with acute severe asthma. The role of T lymphocytes in granulocyte chemotaxis and activation was also explored, using recombinant human lymphokines, and we have identified and characterized two lymphokines which have specific effects upon neutrophils.

Acute Disease↗

Postnatal changes in an alpha subunit isoform, alpha(S), of Na+,K(+)-ATPase in the submandibular gland of rats.

The alpha and alpha(+) isoforms of Na+,K(+)-ATPase were isolated from the kidney and brain of rats and purified. Their antisera were raised to analyze the alpha isoforms in rat tissues. We found that the submandibular gland (SMG) contains a new immunoreactive alpha subunit isoform, designated alpha(S) in this report, in addition to alpha identical with those found in the kidney or brain. The new alpha(S) strongly reacted with anti-alpha-antiserum but to a much lesser extent with anti-alpha(+)-antiserum. The alpha(S) had a slightly lower molecular weight (approximately 90,000) than the brain and kidney alpha isoforms. Various fractions of SMG tissues were added to the SMG microsomes and incubated in order to test whether or not the alpha(S) is formed artificially; no increase of alpha(S) was observed by these treatments, suggesting that the alpha(S) was not the product formed from alpha during the preparation of microsome sample, but was rather a protein originally present in the SMG. The alpha(S) protein was not detected in the SMG of 2- or 5-week-old rats, but it gradually increased in rats older than 8 weeks, reaching the maximum in 30-week-old animals. The Na+,K(+)-ATPase activity in the SMG increased concomitantly with the increase of alpha(S), indicating that Na+,K(+)-ATPase comprising alpha(S) also shows enzyme activity; it is speculated that alpha(S) may have some unique and unknown function(s) in older rats.

Animals↗

Coronary aneurysms in a young adult: report of a case suspected of Kawasaki disease.

An autopsy case of coronary aneurysm was reported. The patient, a 23-year-old Japanese man, suddenly fell unconscious during a karate match and died an hour later. The autopsy revealed coronary aneurysms, one of which was accompanied by thrombosis. Histologically, the aneurysmal walls showed marked scar formation and intimal thickening and the state was regarded as healed arteritis. By taking a precise history from his parents, Kawasaki disease was thought to be the probable cause of the coronary aneurysms.

Adult↗

A simple and rapid purification procedure for the preparation of tetramethylrhodamine-labeled antibodies.

A conjugate preparation of antibody (Fab) and tetramethylrhodamine (TMR) generally adsorbs free TMR which is very difficult to remove because of its strong hydrophobic binding. On the basis of criteria such as sodium dodecyl sulfate (SDS) gel electrophoresis and staining of the plasma membrane of live cells, we found that simple extraction with n-butyl alcohol or iso-amyl alcohol could remove the contaminating free dye. The procedure is especially useful when one needs to prepare conjugates with low nonspecific binding for the study of lateral diffusion of cell membrane-associated antigens.

1-Butanol↗

[Effect of different kinds of toothbrushes on toothbrushing pressure and plaque removal in the scrubbing method of toothbrushing (5). Toothbrushes with nylon bristles arranged in different lengths along the toothbrush shank and with different types of toothbrush bristle tip].

The purpose of this study (Report 5) was to investigate the effect of difference in the length of toothbrush shank and type of tip of toothbrush bristle on toothbrushing pressure and plaque removal in the scrubbing method. Four kinds of toothbrushes which were different in length of shank (30 mm, 40 mm) and type of bristle tip (round type, tapered type respectively) were used in this study. Referring to the results of our previous reports (1-4), the dimension of new toothbrushes were determined as follows, nylon bristles: 40 mm long and 0.20 mm in diameter, brushing surface: 30 mm long, bristles: 3 rows with 26 tufts, and a straight handle. Twelve subjects participated in this experiment. Plaque scores were measured before and after toothbrushing. Then plaque removal rates were calculated. Toothbrushing pressure was determined using Watanabe's method. The average toothbrushing pressure of the toothbrush with a 40 mm long shank (301.6 +/- 84.1 g/cm2) was higher than that with a 30 mm long shank (294.7 +/- 74.8 g/cm2), and that with a tapered bristle type (316.7 +/- 90.4 g/cm2) was higher than that with a round type bristle (279.6 +/- 61.7 g/cm2). However statistically significant differences were not found among the four toothbrushes in brushing pressure and in plaque removal on total teeth surfaces and on distal surfaces of the most posterior teeth (P less than 0.05; two-way ANOVA).

Dental Plaque↗

The blood vascular architecture of the salamander external gill: a scanning electron microscopic study of corrosion casts.

The blood vascular architecture in three-paired external gills of salamander tadpoles, Hynobius dunni Tago, was demonstrated with special reference to metamorphosis by scanning electron microscopy of vascular corrosion casts. In the fully developed gill, each of the three-paired afferent branchial arteries gave off secondary afferent filament arterioles. The afferent filament arteriole drained toward the efferent filament arteriole, forming the loop at the posterior extremity of the gill filament. The branched capillaries from the afferent filament arteriole formed two plates of respiratory capillary networks with irregular honeycomb-shaped meshes. In addition, there were non-respiratory shunts as bypass of the blood circulation between the afferent and efferent branchial arteries without branching filament arterioles. Furthermore, the deep venous plexus and subepithelial capillary plexus were seen around each efferent branchial artery. The filament central venule in the central part of the filament merged into the venous plexus. Nutritive capillaries branched from efferent branchial arteries also drained toward the venous plexus. Such general vascular architecture is simpler than that of the fish. During metamorphosis, the pattern of the vascular distribution, especially filament net capillaries became irregular, and then markedly tortuous or convoluted blood vessels occurred in the absorbing gill. At the metamorphic climax, the capillary network practically disappeared in the remnant of the gill but the bypass shunt as a non-respiratory artery remained almost unchanged.

Animals↗

Studies on the salivary secretion induced by substance P in perfused submandibular gland of rat.

The purpose of these experiments was to clarify the effects of substance P (SP) on the salivary secretion in comparison with those of autonomic agents. Salivary secretion from rat submandibular gland (SMG) was induced by intravenous infusion into the femoral vein or partial perfusion of SMG with isotonic solution containing SP or autonomic stimulants. Blood and salivary flow rates, and electrolyte concentrations of saliva were measured. The relationship between electrolyte concentrations and salivary flow rate after intravenous infusion of SP was similar to that obtained using parasympathomimetic agents. Salivary flow rates induced by phenylephrine and isoproterenol were significantly increased by the further addition of SP, while the pilocarpine-induced flow rate was not affected. SP alone caused a significant increase in blood flow rate of perfused rat SMG. SP with atropine or phentolamine somewhat increased the blood flow. However, concomitant perfusion of atropine and phentolamine completely inhibited the SP effect. Salivary secretion induced by SP perfusion was reduced by atropine or phentolamine. Both blood flow elevation and salivary secretion induced by SP were reduced with increasing doses of a SP-antagonist. Also blood and salivary flow responses induced by phenylephrine were severely reduced by the SP-antagonist. On the other hand, the salivary secretion induced by pilocarpine was moderately reduced by the SP-antagonist. These results indicate that the salivation and especially the glandular vasodilation induced by SP were partially modified by the autonomic agents.

Animals↗