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M Araki

Publications and source records attributed to M Araki.

At least 127 records · Page 7Linked to original sources
PubMed1994

[The interrelation of serum lysozyme level and cytoplasmic lysozyme level].

By means of the immunocytochemical method, the level of cytoplasmic lysozyme in leukocytes from healthy volunteers (n = 50) and from patients with uremia (n = 50), leukocytosis (n = 50), various forms of leukemia (n = 36) and myelodysplastic syndrome (MDS) (n = 7) were analysed, and compared with that of simultaneously assayed serum lysozyme. Both the cytoplasmic and serum levels of lysozyme in uremia and leukocytosis were significantly higher than normal subjects (p < 0.001). No correlation, however, was found between their cytoplasmic and serum levels of lysozyme. Morphological analysis for various kinds of leukemia and MDS indicated that myelocytic and monocytic cells became highly positive for lysozyme staining with maturation, and that lymphocytes, leukemic myeloblasts and monoblasts were negative. The cytoplasmic and serum lysozyme levels of leukemias or MDS having a number of lysozyme-positive cells were elevated as compared with those of normal individuals. Among them acute myelocytic leukemia (FAB M4) revealed an excellent correlation between the lysozyme levels in cytoplasm and in serum. The rest whose serum lysozyme level tend to be lower than the cytoplasmic one gave poor correlation. Thus, serum lysozyme level is not fully reflected by the cytoplasmic level. The dual determination of cytoplasmic and serum lysozyme is suggested to be helpful on estimating leukemia types, the degree of cellular maturation and total cell mass, and might also provide a valuable tool for prediction of prognosis for these disorders.

Cytoplasm↗
PubMed1993

Sp1 binds to the adhesion-molecule-on-glia regulatory element that functions as a positive transcription regulatory element in astrocytes.

We analyzed cis-acting elements regulating the expression of the gene encoding adhesion molecule on glia (AMOG) in primary cultured astrocytes from newborn rat cerebrum and cerebellum. The relative promoter activities among the series of 5' sequential deletion mutants are similar to those observed in B103 (rat neuroblastoma cell line) cells. The previously identified AMRE (AMOG regulatory element) of the GAGGCGGGG sequence functions as a positive regulatory element, not only in B103 cells, but also in astrocytes. Binding factors to the element were identified as Sp1 based on the following observations using nuclear extracts from the astrocytes and B103 cells: (1) The interaction of the factors with AMRE analyzed by DNase I footprinting and methylation interference analyses was similar to that of Sp1; (2) The binding of the factors to AMRE competed with an oligonucleotide containing the authentic Sp1 consensus sequence; (3) Sp1-specific antibody interfered with the formation of the AMRE gel retardation complexes. The functional implications of the factors in AMOG gene regulation are discussed.

Adenosine Triphosphatases↗
PubMed1993

Early changes of macrophage-like immunoreactivity in the rat inferior olive after intraperitoneal 3-acetylpyridine injection.

Early changes of macrophage-like immunoreactivity were observed in the inferior olive after intraperitoneal injection of 3-acetylpyridine (3AP) using seven monoclonal antibodies recognizing macrophage subpopulations (OX-42, OX-6, ED-1, RM-1, TRPM-1, TRPM-2, and TRPM-3). Both resting and activated forms of microglia were stained with OX-42 and TRPM-2. Some of activated microglia reacted to OX-6 and/or ED-1. Neither resting nor activated microglia reacted to any of RM-1, TRPM-1, and TRPM-3. Four h after 3AP injection, the processes of OX-42-positive microglia had increased in number and became thicker than resting microglia. Between 24 h and the 7th day after 3AP injection (day 7), OX-42-positive microglia gradually increased in number. At 24 h after 3AP injection, round cells appeared that stained with all seven antibodies. These disappeared by day 3. Double staining indicated that OX-42-positive activated microglia on day 7 were divided into subpopulations by their immunoreactivity to ED-1. We suggest that the round cells derived from blood monocytes and entered the brain only transiently while OX-42-positive activated microglia originated from parenchymal resting microglia and continued to increase in number after the disappearance of the round cells.

Animals↗
PubMed1993

Cloning and sequencing of mouse VCAM-1 cDNA.

We report here the nucleotide sequence of a cDNA encoding the mouse vascular cell adhesion molecule-1 (VCAM-1), a member of the immunoglobulin gene superfamily. The 2972-bp cDNA encodes 739 amino acids (aa) and shows 76.4% and 75.9% similarity with the human VCAM-1 nucleotide (nt) and aa sequence, respectively. Three independent cDNA clones had a 7-Ig unit structure (molecule containing a seven 'immunoglobulin motif' repeat), and only sequences corresponding to the 7- (and not to the 6)-Ig unit VCAM were detected by reverse transcription polymerase chain reaction (RT-PCR), indicating that in the mouse this is the dominant, if not exclusive, form of this molecule. Unlike other adhesion molecules, the cytoplasmic tails (19 aa) of mouse and human VCAM-1 are identical, despite a 85.2% similarity only at the nt level, suggesting a critical functional role.

Amino Acid Sequence↗
PubMed1993

A new enzyme-linked immunosorbent assay (ELISA) for studying immunocytochemical procedures using an antiserum produced against spermidine as a model.

Antiserum was produced in rabbits against the polyamine spermidine (Spd) conjugated to bovine serum albumin (BSA). The reactivity of the serum to Spd and a variety of structurally related compounds was quantified by a new immunocytochemical model system incorporating an enzyme-linked immunosorbent assay (ELISA) binding test. This is based on the principle of coupling these compounds to the wells of microtiter plate activated with poly-L-lysine and glutaraldehyde and incubating the wells by the indirect immunoperoxidase method. The antiserum showed a 25% cross reaction with spermine (Spm), putrescine (Put), and cadaverine (Cad), and a 1% cross reaction with 1,3-diaminopropane (Dap), but no cross reaction with monoacetyl polyamines and amino acids. The antibody binding was inhibited most effectively by absorption of the antiserum with N1-acetylspermidine and Spd in the ELISA inhibition test. Also, immunoblot analysis of the antiserum with nitrocellulose paper gave completely identical results to the ELISA binding tests. Spd-like immunoreactivities in human melanoma BD and neuroblastoma IMR 32 cell lines are presented as examples of the staining pattern obtained with the antiserum. Absorption of the serum with N1-acetylspermidine and Spd was demonstrated to abolish the immunostaining reaction. The immunohistochemical model is simple: amines and amino acids are bound in the same way as in aldehyde-fixed tissues and, in comparison to immunoblot analysis, the immunoreactivity can be more easily and accurately quantified by assay with the antibody. The model should prove useful in assessing the specificity of other antisera.

Enzyme-Linked Immunosorbent Assay↗
PubMed1993

K252a, a potent protein kinase inhibitor, improves endotoxic lethality and glucose dyshomeostasis.

To investigate whether the inhibition of protein kinases including protein kinase C can antagonize endotoxicosis, the in vivo effects of K252a, a potent inhibitor of protein kinases, on endotoxin-induced lethality and glucose dyshomeostasis were determined in conscious rats. Sprague-Dawley rats (260-340 g) were divided into the following four groups: Group DS, 2.5% dimethyl sulfoxide (DMSO), 6 ml/kg iv + 0.9% saline, 2 ml/kg iv; group KS, K252a in 2.5% DMSO, 4 mg/kg iv + 0.9% saline; group DE, 2.5% DMSO + endotoxin (E. coli), 15 mg/kg iv; and group KE, K252a in 2.5% DMSO + endotoxin. A quarter of DMSO or K252a solution was continuously infused over a 15 min period before a bolus injection of either saline or endotoxin. The remaining dose was administered over a 180 min period after saline or endotoxin. All animals in the DS and KS groups survived for 24 hrs. K252a significantly improved endotoxic lethality. It attenuated the initial hyperglycemia, and late hypoglycemia, hyperlactacidemia, and base deficit after endotoxin. However, K252a had no influence on the endotoxic alterations of blood pressure, PaCO2 or PaO2. These results suggest that the activations of protein kinases, particularly protein kinase C, are involved in the pathogenesis of lethal endotoxicosis and sepsis.

Animals↗
PubMed1993

The capacity of central and peripheral catecholaminergic neurons to innervate the pineal organ and cerebral cortex of the rat: in vitro immunohistochemical observations.

The locus coeruleus (LC) or superior cervical ganglion (SCG) of neonatal rats were co-cultured either with the pineal organ or cerebral cortex (CX) to investigate the innervating capacity of central and peripheral catecholamine neurons under these experimental conditions. After 2 weeks of co-culturing, cultures were fixed for tyrosine hydroxylase (TH) immunohistochemistry to examine the distribution of catecholamine neurons and their fibers. Glial fibrillary acidic protein and fibronectin immunohistochemistry was performed to determine the cell types proliferating around the explants. In LC/CX co-cultures, numerous astrocytes spread between the two explants, and TH-immunoreactive neurites were generally seen to invade CX explants. In contrast, neurite extension from LC to pineal explants occurred only when a glial cell sheet grew between the two explants, and when the pineal explants were not surrounded by a tight fibronectin-positive cell layer. Neurites of the SCG usually invaded both CX and pineal explants, regardless of the existence of glial or non-glial cell layer. These results indicate that central and peripheral catecholamine neurites have the potential of invading both the cortex and pineal, although they are distributed only in particular regions of the intact brain. The distribution of LC neurites, however, seems to be profoundly affected by the cell types spreading around the explants; glial cells appear to support LC neurite extension, whereas non-glial cells appear to inhibit it.

Animals↗
PubMed1993

Modification of hepatic protein kinase C with phorbol myristate acetate and staurosporine alters hemodynamics in the perfused rat liver.

Activation of protein kinase C (PKC) has been implicated in the pathogenesis of endotoxicosis and severe sepsis. Since hepatic blood flow and metabolism have been known to be altered in endotoxicosis and sepsis, we studied the hemodynamic effect of PKC modulation with phorbol 12-myristate 13-acetate (PMA) and staurosporine (St) on the perfused rat liver. The liver was isolated from overnight-fasted male Sprague-Dawley rats and placed in a recirculating perfusion apparatus. The liver was perfused with Krebs-Ringer-bicarbonate solution at a constant pressure of 12 cmH2O. Flow to the liver was continuously monitored with an electric magnetic flowmeter. PMA at an initial concentration of 2 x 10(-8) M significantly decreased hepatic flow. Staurosporine (St), a potent PKC inhibitor at 4 x 10(-7) M produced a small increase in hepatic flow. Pretreatment with St significantly attenuated the flow reduction by PMA. St significantly suppressed the flow reductions by 4 x 10(-6) M of prostaglandin E2 and D2. These results suggest that the PKC inside the liver may play an important role in the regulation of hepatic blood flow during endotoxicosis and sepsis.

Journal Article↗
PubMed1993

Prostaglandin E1 (PGE1) attenuates vasoconstriction induced by PGE2, PGD2 and phorbol myristate acetate in the perfused rat liver.

It has been shown that prostaglandins (PGs) produced by Kupffer and endothelial cells play an important role in mediating physiological responses to various immunological stimuli. We studied the effect of prostaglandin E1 (PGE1) on the hemodynamic and metabolic changes induced by prostaglandin E2 (PGE2), D2 (PGD2) and phorbol 12-myristate 13-acetate (PMA), a potent inducer of PGs in the isolated rat liver perfused with Krebs-Ringer-bicarbonate (KRB) solution at a constant pressure of 12 cmH2O. The liver was taken from overnight-fasted male Sprague-Dawley rats weighing 260 to 310 g. Both PGE2 and PGD2 significantly decreased hepatic flow when their initial concentration was elevated to micromolar range. Although 1 x 10(-6) M of PGE1 did not have a major effect on hepatic flow, it significantly attenuated the declines of hepatic flow produced by 4 x 10(-6) M of PGE2 and PGD2. However, none of PGs tested influenced glucose and lactate concentrations in the medium. Continuous infusion of PGE1 into the medium at a rate of 5 microg.min(-1) significantly diminished the decreases in hepatic flow and oxygen consumption induced by 2 x 10(-8) M of PMA. These results suggest that administration of PGE1 may preserve hepatic blood flow by modifying the intrahepatic regulatory mechanism involving the activation of Kupffer and endothelial cells.

Journal Article↗
PubMed1993

Fibrinolytic components in fetal membranes and amniotic fluid.

OBJECTIVE: We evaluated fibrinolytic components in plasma and amniotic fluid of pregnant women and in postpartum fetal membranes. STUDY DESIGN: Fibrinolytic parameters in amniotic fluid and plasma were measured by means of enzyme-linked immunosorbent assays. Fetal membranes collected after spontaneous labor at term were analyzed by immunohistochemical methods with immunospecific antibodies against fibrinolytic components. RESULTS: Amniotic fluid contained high plasminogen activator inhibitor-1 concentrations but had low activity. Strong staining for plasminogen activator inhibitor-1 and vitronectin was observed in chorionic trophoblasts and moderate staining in decidual connective tissue. Strong staining for plasminogen activator inhibitor-2 was seen in decidual cells. Although prominent staining of plasminogen activators and plasminogen were observed in the amniotic epithelium, virtually no plasminogen activator inhibitor-1, plasminogen activator inhibitor-2, or alpha 2-plasmin inhibitor staining was detected. CONCLUSION: The delicate balance of fibrinolytic activators and inhibitors in fetal membranes and amniotic fluid may contribute to the triggering of membrane rupture at term.

Amniotic Fluid↗
PubMed1993

Retinal differentiation from multipotential pineal cells of the embryonic quail.

Pineal cells of the embryonic quail are multipotent stem cells which are able to differentiate in vitro into pigmented epithelial cells, lens cells and skeletal muscle fibers. Neuronal expression was added in this study in the repertory of differentiating potency of pineal cells. We used immunohistochemical methods to characterize neuronal properties with antibodies against serotonin, GABA, tyrosine hydroxylase and neuron-specific antigen (HPC-1) in addition to the enzyme histochemistry for acetylcholinesterase activity. Cells in the culture were found to be positively stained with these methods, suggesting that embryonic pineal cells are neuropotent to differentiate various types of neuronal cells. We have studied the culture conditions which favor increment of neuronal cells with extension of neuritic processes, and we have found that neuronal cells are maintained for quite a long period under suppressive conditions of DNA synthesis and under the effect of basic fibroblast growth factor (FGF). Suppression of DNA synthesis was achieved by the addition of aphidicolin, an inhibitor of DNA polymerase alpha, in the medium. Time lapse videograph revealed two different cell types participated in neurogenesis; a minor population of small round cells and a major one of flat epithelial cells. Since embryonic quail pineal cells have been shown to differentiate into two types of photoreceptors, the present results show wider retinal potency of cell differentiation by embryonic pineal cells. The cessation of DNA synthesis as well as growth factor(s) may be positively involved in the mechanisms of determination and differentiation of pineal neurons.

Animals↗
PubMed1993

Modulation of protein kinase C alters hemodynamics and metabolism in the isolated liver in fed and fasted rats.

The activation of protein kinase C (PKC) has been implicated in the pathogenesis of gram-negative sepsis. The effects of PKC modulation on hepatic flow and metabolism were studied using isolated liver perfusion. The liver was isolated from well-fed or overnight-fasted, male Sprague-Dawley rats weighing 250-310 g, and perfused at a constant pressure of 12 cmH2O using a recirculating system. Phorbol 12-myristate 13-acetate (PMA), a potent activator of PKC, decreased hepatic flow and oxygen consumption, and increased net lactate production. It enhanced net glucose production in fed animals. Neither 4 alpha-phorbol didecanoate, an inactive phorbol ester for PKC nor 4 alpha-phorbol, an inactive phorbol had any significant effect. The effects of PMA were augmented by increasing calcium concentration in the medium. PMA at an initial concentration of 4 x 10(-8) M stimulated net lactate and/or glucose production more than a reduction of perfusion pressure from 12 to 6 cmH2O. Staurosporine, a potent PKC inhibitor, significantly attenuated the PMA-induced alterations of hepatic flow and oxygen consumption. These results indicate that modulation of PKC exerts significant effects on hepatic flow and metabolism, which are dependent on extracellular calcium concentrations and feeding conditions, and that the effect of PMA on carbohydrate metabolism is not merely attributed to decreases in hepatic flow and oxygen consumption. It is suggested that PKC activation may be involved in the alterations of hepatic flow and metabolism during severe sepsis.

Alkaloids↗
PubMed1993

Chemical structures of two subunits, A-subunit and B-subunit, of galactose-specific isolectins from Erythrina variegata seeds.

We previously isolated galactose-specific isolectins, EVLI, EVLII, and EVLIII, from the Erythrina variegata seeds [J. Chromatogr. 597, 207-211 (1992)]. The amino acid sequences of the two subunits, A- and B-subunits, of which the isolectins are composed, were determined. A comparison of the amino acid sequences of tryptic peptides from the two subunits revealed seven amino acid substitutions. Among them, Asn46, to which the oligosaccharide chain is linked in the A-subunit, is replaced by Asp46 in the B-subunit, causing the B-subunit to lack one glycosylation site. The N-linked oligosaccharides of these subunits were also analyzed. The N-linked oligosaccharides were first liberated by hydrazinolysis. After N-acetylation, the reducing ends of the oligosaccharides were coupled with 2-aminopyridine, and then the pyridylamino (PA-) derivatives were purified by gel filtration and HPLC on an ODS-silica column. One major sugar chain, accounting for more than 98% of the total, was purified from both species. The structure of this major sugar chain was established to be Man alpha 6(Man alpha 3)(Xyl beta 2)Man beta 4GlcNAc beta 4(Fuc alpha 3)GlcNAc. This finding that there is no structural difference of the sugar chains linked to the two subunits of E. variegata lectins, together with the results of amino acid sequence comparisons, indicates that the difference in molecular mass of these two subunits results almost wholly from the difference in the number of oligosaccharides linked to them.

Amino Acid Sequence↗
PubMed1993

[A case of angiosarcoma of the heart with cardiac tamponade and repeated hemoptysis].

A 30-year-old man who died from brain metastasis of cardiac angiosarcoma is presented. His chest X-ray film showed cardiac tamponade and bilateral pleural effusion. His symptoms were improved only by drainage of the bloody pericardial and pleural effusion. During the course of the disease, multiple nodular infiltrates were seen on chest CT and hemoptysis occurred repeatedly. He presented to our hospital. On the first night of hospitalization, symptoms including headache, vomiting and disturbance of consciousness appeared and brain CT showed suspected brain metastasis. He died on the 20th hospital day with no definite diagnosis having been established. At postmortem examination, a hen's egg sized cardiac angiosarcoma was found infiltrating the right atrial wall. Metastatic foci were found in the epicardium and bilateral lungs. This case was considered to be angiosarcoma of the heart, manifesting various clinical symptoms because of bleeding from the metastatic foci.

Adult↗
PubMed1992

A PCR analysis of rhodopsin gene transcription in rat pineal photoreceptor differentiation.

A polymerase chain reaction (PCR) method was used to detect rhodopsin transcripts in rat pineals both in vivo and in vitro. Only very low levels of transcripts were detected in preparations from adult rat pineal tissue, but fairly large amounts were detected in cDNA preparations from cultures of newborn rat pineals. The transcript level was reduced significantly if the cells had been cultured in the presence of 10 microM norepinephrine (NE). This concentration of NE had previously been shown to abolish almost completely the rhodopsin immunoreactivity normally seen in such cultures. The present work indicates that part, but not all, of the effect of NE is probably at the level of translation.

Animals↗
PubMed1992

The embryonic pineal body as a multipotent organ.

The repertoire of differentiating potency of mammalian and avian pineal cells has been examined utilizing cell culture technique. Skeletal muscle fibers are differentiated from pineal cells of the rat under the usual culture condition and from those of quail under hypertonic conditions. Myogenesis of pineal cells may be explained from the ontogeny of the pineal body. Anlagen of a pineal body are situated in bilateral cephalic neural folds, which also supply multipotent neural crest cells. In some conditions, almost all quail pineal cells are able to differentiate into pigmented epithelial cells and/or lens cells. Opsin containing cells found in culture of rat pineal cells may be in a similar category reflecting the "third eye": the phylogenetic ancestor of the pineal body of avian and mammalian species. Neuron-like cells have also been reported and neuronal morphology has been intensified under the effect of testicular hyaluronidase. The cytodifferentiation described above is suggested to be different expressions of a single type of progenitor cells in the pineal body. In relation to multipotentiality of pineal cells, the original differentiating state of pineal cells is interesting; it has been found that tyrosinase is expressed from the beginning of pineal formation and that its expression is stage-specific (during embryonic period) and site-specific (predominance in the dorsal half of the pineal body and in the apical cytoplasm of the pineal cell). In the 8 day quail embryo used for culture studies, three differentiating states as to tyrosinase are noticed. However, the distinction may be apparent, as even the cells negative in tyrosinase in this stage are still ready to express tyrosinase in the suitable culture condition.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1992

Isolation and characterization of isolectins from Erythrina variegata seeds.

Three isolectins were isolated from seeds of Erythrina variegata (Linn.) var. Orientalis by ion-exchange chromatography, followed by affinity chromatography on lactose-Sepharose 4B and acid-treated Sepharose 4B columns. The purified isolectins (EVLI, EVLII and EVLIII) are all specific for galactopyranosides and N-acetylgalactosamine, and their affinities for simple sugars are EVLIII greater than EVLII greater than EVLI. EVLI and EVLIII are homodimers made up of an A-subunit of molecular mass 36,000 and a B-subunit of molecular mass 33,000, whereas EVLII is a heterodimer composed of the A- and B-subunits. Upon treatment with trifluoromethansulphonic acid, the molecular masses of both subunits decreased to 31,000. Rechromatography of EVLII on the acid-treated Sepharose 4B column again produced the homodimeric lectins (EVLI and EVLIII). It is suggested that the constituent subunits of Erythrina variegata isolectins are eschangeable with each other in vitro.

Amino Acids↗