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Biomedical subjects

K Takatsuki

Publications and source records attributed to K Takatsuki.

At least 541 records · Page 30Linked to original sources
PubMed1982

Modulation of Tac antigen on activated human T cells by anti-Tac monoclonal antibody.

A monoclonal antibody termed anti-Tac antibody is reactive with activated and functionally mature human T cells, but not reactive with resting T cells or B cells. We found that the expression of Tac antigen on activated T cells was inhibited by the addition of anti-Tac antibody in the culture of T cells activated with Con A or alloantigen. In the mixed lymphocyte culture, the expression of Ia-like antigen on allo-activated T cells was also inhibited by anti-Tac antibody, although the antibody does not recognize Ia-like antigen. However, anti-Ia monoclonal antibody did not suppress the expression of either Tac or Ia-like antigen. In addition, Tac antigen expressed on activated T cells was modulated by anti-Tac antibody cultured with activated T cells at 37 degrees C for 48 hr. Antigenic modulation, which means a specific loss of Tac antigen from the cell surface of T cells, was detected by the indirect immunofluorescence method. Tac antigen was reexpressed on T cells after restimulation when the anti-Tac antibody was removed, whereas Ia-like antigen already expressed on allo-activated T cells was not modulated by anti-Tac antibody. These results suggest that Tac and Ia-like antigens are carried on different molecules, both of which are closely linked in expression on activated T cells. The expression of Tac antigen may be essential for the following expression of Ia-like antigen.

Antibodies, Monoclonal↗
PubMed1982

Gas chromatographic determination of propionates as paranitrobenzyl ester in bakery products.

A procedure was developed to determine propionates used as mold inhibitors and preservatives in bakery products. Propionates were extracted from the sample with water alkalinized by potassium carbonate. Water was evaporated, and the residue was reacted with paranitrobenzyl bromide in dimethyl-formamide-water (90 + 10) at room temperature to convert propionates to paranitrobenzyl ester, which was determined with a gas chromatograph equipped with a flame ionization detector. Bakery products, such as bread, sponge cake, cookies, and biscuits, were analyzed by this procedure. Recoveries from samples fortified with propionates ranged from 94 to 101%, with a standard deviation of 3.32. The concentrations determined were 50 to 2500 micrograms/g sample.

Bread↗
PubMed1982

Coexistence of Kimura's disease and lichen amyloidosus in three patients.

Three patients had Kimura's disease with multiple asymptomatic subcutaneous tumors of 11 to 20 years' duration on the head, soft palate, elbow, or inguinal regions associated with enlarged regional lymph nodes. In each patient, lichen amyloidosus had also developed on the extensor surfaces of the extremities during the past 12 to 20 years. Blood eosinophilia (26% to 75%) was present in all cases. The possible pathogenetic relationship between Kimura's disease and primary localized cutaneous amyloidosis is discussed.

Adult↗
PubMed1981

Ontogeny of somatostatin-containing neuron system of the rat: immunohistochemical observations. I. Lower brainstem.

The ontogeny of the somatostatin (SRIF) neuron system in the lower brainstem of the rat was analyzed using the indirect immunofluorescence technique of Coons. SRIF-positive structures first appeared in the primordium of the ventral nucleus of the lemniscus lateralis of the rat fetus corresponding to gestational day 15 (12-14-mm embryos). On and after gestational day 15, these structures appeared in progressively more diverse areas of the lower brainstem and continued to show an increase in number and intensity up till birth. The maximum SRIF-positive structures were histochemically identified in the lower brainstem at the perinatal stage. However, after birth, the numbers of SRIF-positive structures in the lower brainstem began to decrease as the rat grew and none or only a few SRIF-positive structures were detected in the adult rats. This ontogenetical study of the SRIF neuron system on the lower brainstem of the rat strongly suggests that SRIF might play an important role in the development of the lower brainstem other than in its neurotransmitter or neuromodulator function.

Aging↗
PubMed1981

Morphological study of noradrenaline innervation in the caudal raphe nuclei with special reference to fine structure.

Previous histofluorescence studies have demonstrated that the caudal raphe nuclei (CRa) of the rat, particularly the ventral portion (VCRa), contains a very high density of noradrenaline (NA) terminals and in the present study we attempted to elucidate the origins and free structure of the NA terminals in this region. The majority of NA terminals found in the VCRa originated from A1 and A3 NA neurons and disclosed that a small number of very strongly fluorescent fibers located along the blood vessels arise from the superior cervical ganglion (SGC). Electron microscopic analysis after potassium permanganate fixation demonstrated that the NA terminals originated from A1 and A3 NA neurons are connected with neuronal elements, while NA fibers from the SGC were identified among the vascular elements. Axodendritic contacts were found to be predominant among the synapselike contacts of NA terminals in this area.

Animals↗
PubMed1981

Distribution of somatostatin in the frog brain, Rana catesbiana, in relation to location of catecholamine-containing neuron system.

The distribution of somatostatin (SRIF)-immunoreactive structures in the central nervous system of the bull frog (both with and without treatment of colchicine) was studied, using the indirect immunofluorescence technique of Coons and co-workers (Coons, '58). SRIF-containing cells were observed in more than ten areas including the spinal cord. These SRIF-positive cells showed segmental distribution, in that SRIF-positive neurons were identified in various areas at various brain levels. An extensive network of SRIF-positive fibers was found in most parts of the central nervous system. The distribution of a catecholamine (CA)-containing neuron system in the frog brain is also presented in this study. The possible interactions between SRIF and CA neurons systems are briefly discussed.

Animals↗
PubMed1981

Topographic atlas of somatostatin-containing neurons system in the avian brain in relation to catecholamine-containing neurons system. I. Telencephalon and diencephalon.

The morphological organization of the somatostatin (SRIF)-positive neurons in the forebrain (telencephalon and diencephalon) of the warbling grass parakeet (Melopsittacus undulatus) was studied using the indirect immunohistochemical technique of Coons and co-workers ('58). In the telencephalon, a number of SRIF-positive neurons was detected in the lobus paraolfactorius, hippocampus, and paleostriatum. Furthermore, scattered SRIF-labeled cells were noticed in the area corticoidea dorsolateralis and area temporoparieto-occipitalis. A moderate density of immunoreactive fibers was found in the above areas. In addition, although the septal areas was devoid of SRIF-positive neurons, this area contained a moderate occurred in the following hypothalamic areas: (1) nucleus medialis hypothalami posterior, (2) lateral hypothalamus, and (3) mammillary nucleus. The bird hypothalamus also received a strikingly massive SRIF innervation. The heaviest concentration of SRIF-labeled fibers was detected in the medial eminence. Many SRIF-labeled fibers were also observed in other hypothalamic regions. Their locations roughly corresponded in many cases to the areas in which SRIF-positive neurons were disclosed. The overall distribution of the catecholamine system (CA) of the avian forebrain is also represented by means of histofluorescent technique. A possible interaction between SRIF and CA neurons systems is briefly discussed.

Animals↗
PubMed1981

Topographic atlas of somatostatin-containing neuron system in the avian brain in relation to catecholamine-containing neuron system. II. Mesencephalon, rhombencephalon, and spinal cord.

With the indirect immunofluorescence technique of Coon's and collaborators, overall distribution of the somatostatin (SRIF)-positive neurons system in the avian lower brain stem was explored. Numerous cell somata containing SRIF were identified in the interpeduncular nucleus and substantia grisea centralis (GCT) at the level of the nucleus nervi trochlearis. Furthermore, a moderate number of SRIF-positive neurons were seen in the tectum opticum, nucleus tractus solitarii, and spinal cord. Scattered labeled cells were noticed in the rhombencephalon. A dense network of SRIF-positive fibers was distributed widely in the lower brain stem of birds. Their locations corresponded in many cases to the areas where SRIF-positive neurons were found. The present study also presents the distribution of the catecholamine (CA) neuron system in the avian lower brain stem. Possible interactions between SRIF and CA neurons systems are briefly discussed.

Animals↗
PubMed1981

Comparative anatomy of the distribution of catecholamines within the inferior olivary complex from teleosts to primates.

The distribution of catecholamine (CA) in the inferior olivary complex (IO) of various vertebrate (from fish to monkey) was investigated by means of the histofluorescence technique. In addition, using rats, a further attempt was made to elucidate the origins of CA in the IO. The IO of the lower vertebrates (from fish to birds) was in general poorly innervated by the CA neuron system. IO in the lower mammals, such as insectivora and bats, contained only a few CA nerve terminals, while that in the higher mammals such as rat, guinea pig, rabbit, cat, and monkey revealed quite a number. In these animals, species-species patterns of CA nerve terminals were found. In the rat, the highest concentration was observed in the dorsal lamella of the principal nucleus and in guinea pig ventral lamella. In the rabbit and cat, maximum CA nerve terminals were detected in the dorsal accessory nucleus, while in the monkey, they were detected in the medial accessory nucleus. The retrograde tracer technique of horseradish peroxidase (HRP) suggested that the main source of the abundant CA terminals in IO of the rat might be A1, A2, and A3 noradrenaline neurons, though not locus coeruleus and not dopaminergic ones.

Animals↗
PubMed1981

Experimental immunohistochemical studies on the amygdalofugal peptidergic (substance P and somatostatin) fibers in the stria terminalis of the rat.

The amygdalofugal substance P (SP) and somatostatin (SRIF) neuron systems in the stria terminalis (ST) were investigated by means of the indirect immunofluorescence technique of Coons. SP- and SRIF-positive cells were mainly located in the area (Amc) between the central (ac) and medial (am) amygdaloid nuclei. Some extended medially into the am and laterally into the ac. Destruction of the Amc resulted in a marked reduction of SP- and SRIF-positive fibers in the ST. Furthermore, a substantial decrease in SP-positive fibers was seen in the dorsal part of the bed nucleus of the ST (stb), there was a small decrease in the SP-positive fibers in the lateral hypothalamus (LH), a significant decrease in the SRIF-positive fibers in the lateroventral part of the anterior hypothalamic nucleus (lvAH), and a small decrease in the SRIF-positive fibers in the LH. These facts indicate that the origins of a number of SP- and SRIF-positive fibers are the Amc and that the amygdalofugal SP pathway in the ST innervates stb and LH and the amygdalofugal SRIF pathway in the ST projects to lvAH and LH.

Amygdala↗
PubMed1981

Regional distribution of substance P-like immunoreactivity in the frog brain and spinal cord: immunohistochemical analysis.

With the indirect immunofluorescence technique of Coons, the overall distribution of the substance P (SP)-positive neuron system in the frog brain and spinal cord was explored. SP-positive cells were observed in more than ten areas, such as olfactory bulb, amygdaloid complex, septal area, bed nucleus of hippocampal commissure, hypothalamic periventricular zone, dorsal and ventral thalamus, infundibulum, torus semicircularis, optic tectum, the area dorsal to the interpeduncular nucleus, central gray matter of the mesorhombencephalon, and raphe region, etc. A dense network of SP-positive fibers was also widely distributed in the frog brain and spinal cord. SP-positive fibers were roughly divided into two types. One consisted of very fine SP-positive fibers and gave the region a diffuse appearance. The area medial to n. Bellonci, interpeduncular nucleus, n. isthmi, and optic tectum contained this type of SP-positive fibers. The other one consisted of clearly distinguishable varicose fibers. A number of SP-positive fibers located in the amygdaloid complex, striatal complex, hypothalamus, central gray matter of the mesorhombencephalon, trigeminal spinal nucleus, and posterior horn of the spinal cord belonged to this category. The functional role of the SP-positive neuron system in the central nervous system is also briefly discussed.

Animals↗