Search PubMed⌕ Search

Biomedical subjects

S Hirose

Publications and source records attributed to S Hirose.

At least 505 records · Page 28Linked to original sources
PubMed1989

B cell hyperresponsiveness to interleukin 2 and the age-associated decline in murine lupus.

In young NZB x NZW (B/W) F1 mice there was a population of B cells that were hyperresponsive to interleukin 2 (IL-2) and that proliferated but did not differentiate, even in the absence of a prior activation signal, and hence were already stimulated in vivo and were prepared to respond to IL-2. These B cells belonged to the population that was nonadherent to the Sephadex G-10 (G-10) column. We found that such hyperresponsiveness was progressively reduced with the aging of these mice. This event did not appear to be related to the age-associated changes of IL-2 receptors on B cells, since the IL-2-binding ability and the density of IL-2 receptor alpha expressed on B cells in culture did not differ between the young and the old mice. Studies suggested that two major mechanisms are responsible for the age-associated decline in the IL-2 responsiveness of B cells. First, the capacity of IL-2 hyperresponsiveness of such B cells decreases in B/W F1 mice with aging, probably through further activation and differentiation of the B cells. Second, the G-10 adherent, but not nonadherent, B cells from the aged mice inhibit the IL-2 response of G-10 nonadherent B cells. The G-10 adherent B cells from the old mice also inhibited the IL-2 production of T cells from the young B/W F1 mice. Taken together, it appears that young B/W F1 mice bear a population of B cells already stimulated so that they can respond to IL-2 without prior stimuli. With aging, activation of the B cells progresses and they appear to down-regulate the IL-2 hyperresponse of B cells and the IL-2 synthesis by T cells.

Aging↗
PubMed1989

Caudato-nigral transmission in the substantia nigra pars reticulata neurons changes with recovery from circling movements induced by microinfusion of ibotenic acid. I. Behavioral study.

Following creation of a unilateral circumscribed lesion in a portion of a cat substantia nigra pars reticulata by microinfusion of ibotenic acid, circling movements toward the contralateral side of the lesion appeared within 2 days and disappeared a few days later. After recovery, the circling movements reappeared when the cats were decerebrated at the premammillary and precollicular level, suggesting that brain centers rostral to the decerebration participate in compensating the circling movements.

Animals↗
PubMed1989

Caudato-nigral transmission in the substantia nigra pars reticulata neurons changes with recovery from circling movements induced by microinfusion of ibotenic acid. II. Electrophysiological study on synaptic transmission.

Caudato-nigral synaptic transmission was examined by stimulation of the caudate nucleus while recording from nigral neurons in cats recovering from circling movements induced by a unilateral circumscribed lesion in the substantia nigra pars reticulata after microinfusion of ibotenic acid. Extra- and intracellular recording from neurons in lesion-spared areas of the substantia nigra pars reticulata indicated that the caudato-nigral synaptic action on the side ipsilateral to the lesion exhibited a shorter duration of inhibition and a larger amplitude of excitation as a means of compensating for the circling movements.

Action Potentials↗
PubMed1989

Are Ly1 B cells responsible for the IL2-hyperresponsiveness of B cells in autoimmune-prone NZB x NZW F1 mice?

Unlike splenic B cells from normal BALB/c mice, those from autoimmune-prone NZB x NZW (B/W) F1 young mice were hyperresponsive to interleukin 2 (IL2) and proliferated even in the absence of prior stimulation signals. We found that the B cell subpopulation responsible for this event belongs to that with 6B2 (B220)-dull, Ly1(CD5)-positive phenotypes. Cell cycle analysis revealed that the 6B2-dull, Ly1 B cell subpopulation contains a significant number of cells at stages of G1A and G1B, while the majority of 6B2-bright B cells belongs to GO. Therefore, it appears that most of the 6B2-dull, Ly1 B cells in young B/W F1 mice are already stimulated in vivo to the stage of early activation, so that they respond to IL2 without prior stimuli. Unlike other strains of mice, including parental NZB and NZW, the B/W F1 mice showed a rapid decrease in the proportion of splenic Ly1 B cells, beginning at about 6 months of age. This was associated with the hyporesponsiveness to IL2 of 6B2-dull splenic B cell population in the old B/W F1 mice. This phenomenon seems to relate to further activation and differentiation, which occur in Ly1 B cells with aging.

Aging↗
PubMed1989

The novel murine B cell differentiation antigen Lp-3.

The unique murine lymphocyte differentiation antigen, Lp-3, with a mol. wt of approximately 125 kd, was found using a rat monoclonal antibody. The Lp-3 antigen was distributed on a wide variety of myeloid, T cell, and B cell lineages in mice. However, the expression was only found in B cells at certain stages of differentiation. The pre-B and virgin B cells in the bone marrow from 2-month-old BALB/c mice were weakly positive for Lp-3, while the resting B cells in the spleen and lymph node were Lp-3 negative. In contrast, the majority of B cells in the peritoneal cavity, mostly Ly-1 (CD5) B cells, had a brighter fluorescence for Lp-3 than did bone marrow B cells. The Lp-3 antigen could be induced in a high density in approximately one-half of lipopolysaccharide-stimulated, large, blastic spleen B cells. Cell cycle analysis showed that Lp-3 is an early B cell activation antigen which is first expressed at the G1A phase of the cell cycle. Therefore this novel B cell differentiation antigen will be useful for differentiating pre-B and virgin B cells in the bone marrow, resting B cells, and a population of activated B cells in the periphery. In contrast to findings in BALB/c mice, there was an elevated population of B cells with a bright Lp-3 expression in the spleen of autoimmune-prone NZB x NZW F1 mice.

Animals↗
PubMed1989

Effect of polyamines on mitochondrial F1-ATPase catalyzed reactions.

The effect of polyamines on F1-ATPase catalyzed reactions has been studied through the use of submitochondrial particles and F1-ATPase. ATP degradation catalyzed by submitochondrial particles and F1-ATPase was inhibited by spermine and spermidine. Spermine's inhibition was much greater than spermidine's effect. In contrast, P1-ATP exchange and succinate dependent ATP synthesis catalyzed by submitochondrial particles were both stimulated by spermine. The inhibition of ATPase activity by polyamines probably occurs through polyamine's replacement of Mg2+ on ATP, for the following reasons. (a) The ATPase activity inhibited by spermine was partially recovered when Mg2+ was added. (b) Spermine bound to ATP and phospholipids but not to F1-ATPase; yet spermine inhibited the ATPase reaction catalyzed by F1-ATPase, a protein free of phospholipid. (c) The binding of spermine to ATP was inhibited by Mg2+. The ATP content in polyamine-deficient cells definitely was lower than that in normal cells. On the basis of these results, the possible role of spermine in keeping the ATP concentration at a high level is discussed.

Adenosine Diphosphate↗
PubMed1989

Immunochemical and biochemical distinction of subtypes of atrial natriuretic peptide receptor.

The presence of subtypes of atrial natriuretic peptide (ANP) receptor has been demonstrated by examining the immunological features and ligand specificities of the receptors in various bovine tissues. The antibody probe used was the antiserum raised against the bovine lung ANP receptor, and the tissues examined for the possible presence of different types of ANP receptor were the lung, kidney, adrenal cortex, ovary, choroid plexus, and vascular tissues. When incubated with Triton extracts of these tissues, the antiserum strongly cross-reacted with the ovary, kidney, and choroid plexus receptors as well as the homologous lung receptor (type I). The adrenal and vascular receptors were recognized only weakly, however, suggesting the presence of distinct ANP receptors (type II). In support of this immunochemical subtyping, type I and type II receptors showed a marked difference in their ability to bind the ANP analog atriopeptin I (ANP5-25): type I receptors in the lung exhibited a moderate affinity for atriopeptin I with a KD of 10(-9) M; however, type II receptors in adrenal and artery showed only a weak affinity for the analog with a KD of 10(-6) M. Structural analysis of affinity-labeled ANP receptors by SDS-PAGE indicated that type I and type II receptors have similar disulfide-linked dimeric structures.(ABSTRACT TRUNCATED AT 250 WORDS)

Adrenal Cortex↗
PubMed1989

A novel second-generation polyolefin container for storage of single-donor apheresis platelets.

A non-blow-molded LE-2 polyolefin (PO) container was developed to store single-donor apheresis platelet concentrates (PCs) processed by the Haemonetics Plasma Collecting System (PCS) at 22 degrees C for over 1 day. We molded PO containers with heat-sealing of light-weight polymer alloy films with a thickness of 0.25 mm. The film was made of polymer blends consisting of polypropylene, styrene ethylene butylene styrene-block copolymer, and ethylene ethylacrylate copolymer. The PO container with enough strength and flexibility in routine practice has 2 and 1.6 times higher oxygen and carbon dioxide gas transfer properties than standard polyvinyl chloride (PVC) plastic containers. PCs (1-1.9 x 10(11) platelets) processed from 450 ml platelet-rich plasma were stored in 0.6-liter PO containers at 22 degrees C with flatbed agitation for up to 6 days. The pH of PCs was well maintained at the mean values of 7.0 in PO containers after 6 days in the well-oxygenated condition. The energy metabolism of stored platelets was determined. Oxygen consumption rates of platelets stored in PO containers averaged 1.5 nmol/min/10(9) platelets. The rates of glucose consumption and lactate production were 0.4 and 0.8 nmol/min/10(11) platelets, respectively. The rates of adenosine triphosphate (ATP) generation of platelets, 9.7 nmol/min/10(9) platelets, in PO containers did not differ from those in the PVC containers. Aggregation responses to adenosine diphosphate and hypotonic shock response of platelets were better maintained in PO containers. The morphological changes into sphere forms with projections and the appearance of unclassified forms were more frequently observed in PO than in PVC containers.(ABSTRACT TRUNCATED AT 250 WORDS)

Blood Component Removal↗
PubMed1989

Relation between soluble interleukin 2 receptor and clinical findings in patients with systemic lupus erythematosus.

The concentration of soluble interleukin 2 receptor (IL-2R) was determined in the serum of 54 patients with systemic lupus erythematosus (SLE) by an enzyme linked immunosorbent assay (ELISA) using two monoclonal antibodies with the IL-2R. Concentrations of soluble IL-2R in the serum of the patients with SLE (study group) were significantly higher than in 20 normal subjects (control group). The relation between concentrations of soluble IL-2R and clinical findings was investigated. The concentration of soluble IL-2R showed no particular relation with the clinical manifestations and did not correlate with the level of anti-DNA antibody or CH50. Significant correlation between the concentration of soluble IL-2R and disease activity did exist, however. Furthermore, the concentration of soluble IL-2R in some cases changed simultaneously with the disease activity. Thus the concentration of soluble IL-2R may serve as a new clinical indicator of disease activity in patients with SLE.

Adult↗
PubMed1989

Subtype switching of ANP receptors during in vitro culture of vascular cells.

Vascular receptors for atrial natriuretic peptide (ANP) have been characterized immunochemically and found to be classified into two subtypes that show differential localization and expression. An antiserum, recognizing the protein core of the receptor, was raised against the purified bovine lung ANP receptor and used for the immunochemical subtyping. ANP receptors solubilized from the bovine jugular vein reacted strongly with the antiserum as well as the homologous lung receptor; however, the receptors from the aorta and carotid artery were recognized only weakly, indicating the presence of two types of ANP receptor in the vascular system. The one that reacts strongly with the antiserum and is distributed mainly in the venous side is termed type I and the other reacting weakly and predominating in the arteries, type II. The two subtypes were also distinguishable in their ligand specificities; the type I receptor showed a remarkably higher affinity for the ANP analogue atriopeptin I than the type II receptor. Surprisingly, similar immunochemical and biochemical analysis of the receptors on cultured vascular smooth muscle and endothelial cells revealed that the arterial cells originally expressing the type II receptor begin to express the type I receptor when cultured in vitro.

Animals↗
PubMed1989

T-cell colony formation in healthy homosexual men without anti-human immunodeficiency virus antibody.

In order to study the abnormal differentiation and proliferation of precursor T cells in homosexual men, a study was made of T-cell colony formation in 15 healthy homosexual men without anti-human immunodeficiency virus (HIV) antibody. The colony forming method used was the one-step monolayer technique using phytohemagglutinin as an inducer. Our results revealed that colony formation was extremely reduced and 3 cases showed no colony growth. However, with the addition of recombinant interleukin 2 to the culture system, the number of colonies increased up to the same level as in heterosexual controls. In addition, the analysis of CD3+, 4+, and 8+ cells of colony component cells revealed a decrease in CD3+ and 4+ cells. However, with the addition of recombinant interleukin 2, the numbers of CD3+ cells distinctly increased. The above results suggest that a disorder in the differentiation and proliferation of precursor T cells in homosexual men might be one of the causes of immunodeficiency.

Adult↗
PubMed1989

Colony-stimulating factors in B-cell colony formation in patients with B-cell chronic lymphocytic leukemia.

A new in vitro colony growth assay system method was found to be reliable in its use for evaluating B-cell proliferation in normal subjects and in 9 patients with B-cell chronic lymphocytic leukemia (B-CLL). The method is based on a phytohemagglutinin (PHA)-stimulated monocyte and T-cell-conditioned medium (PHA-MTCM) composed of PHA, silica, normal monocytes and normal T cells. The number of colonies proliferated was significantly greater in 5 patients who had not undergone treatment than in normal subjects (1,417 +/- 660 vs. 661 +/- 119) (p less than 0.002). Normal cultured B-cell colonies were shown to be 71% surface IgM colonies, and 6% cytoplasmic IgA colonies with the appearance of blastic cells. B-CLL colonies, on the other hand, were demonstrated to be monoclonal with the same CLL circulating cells being retained. We also studied the effect of interleukin-2 (IL-2) on B-cell colony growth assay in 4 patients with B-CLL cells. Only 1 patient with M protein responded to IL-2, proliferated and expressed IL-2 receptors. Although 3 patients without M protein did not respond to IL-2, they did respond to the supernatant, and they proliferated but expressed no IL-2 receptors.

Adult↗
PubMed1989

Immunohistochemical localization of atrial natriuretic peptide receptor in bovine kidney and lung.

Receptors for atrial natriuretic peptide (ANP) were localized in the alveoli and bronchiolar smooth muscle cells of bovine lung and in podocytes of the kidney by immunofluorescence and immunoperoxidase methods. Two specific antisera were raised against the ANP receptor purified from bovine lung plasma membranes: anti-Rc 140 and anti-Rc 70. Anti-Rc 140 was raised against the 140 KD native receptor having a homodimeric structure, and anti-Rc 70 was elicited by immunizing a rabbit with the 70 KD reduced subunits. Essentially identical staining patterns were obtained with both antisera. Identification of ANP receptor sites would provide useful information in understanding the pulmonary and renal actions of ANP.

Animals↗
PubMed1989

Determination of sisomicin in eluate from dried blood spot on filter paper disc for monitoring of blood level in rat, by reversed-phase high-performance liquid chromatography after pre-column fluorimetric derivatization.

About 20 microliters of whole blood obtained by venipuncture from rat tail vein was spotted onto a filter paper and the blood spot was punched out (5 mm diameter). Sisomicin (SISO) in the dried blood spot (DBS) was extracted effectively into 0.5 M Na2HPO4 solution by ultrasonication and determined by reversed-phase high-performance liquid chromatography with pre-column derivatization using o-phthalaldehyde and beta-mercaptopropionic acid. This method could be used for the pre-clinical study of SISO blood levels of a number of mice or rats without killing. The results were identical with those for SISO in serum, if corrected for hematocrit values, and were used for the calculation of pharmacokinetic parameters for individual rats. The detection limit of SISO in DBS (10.1 microliters of whole blood) was 1.0 microgram per ml of whole blood.

Animals↗
PubMed1989

Simultaneous assay of hypoxanthine, xanthine and allopurinol by high-performance liquid chromatography and activation of immobilized xanthine oxidase as an enzyme reactor.

A selective and sensitive assay of substrates (hypoxanthine, xanthine and allopurinol) of xanthine oxidase by reversed-phase liquid chromatography coupled with the use of immobilized enzyme reactors is described. These compounds were oxidized by immobilized xanthine oxidase and produced hydrogen peroxide, which was determined fluorometrically using immobilized peroxidase and p-hydroxyphenylacetic acid. The detection limits of hypoxanthine, xanthine and allopurinol were approximately 50, 120 and 130 pg per injection, respectively. Immobilized xanthine oxidase inhibited by oxipurinol during the assay was reactivated by 2,6-dichlorophenolindophenol and could be used for a long period without a significant activity loss. These methods were applied to plasma and urine samples.

Allopurinol↗
PubMed1989

[Fractional determination of bile acids bound with protein in serum by high-performance liquid chromatography using dual-column switching system].

A simple and rapid technique for the fractional determination of bile acids bound with protein in the serum was developed by using high performance liquid chromatography with a dual-column switching system. The serum samples were directly injected onto a first column (hydroxyapatite), which was initially flushed with 1 mM phosphate buffer. Serum proteins were strongly retained on a column of hydroxyapatite, but free bile acids were not retained. The bile acids were adsorbed on a second column (Serumout-25) and eluted onto a column of immobilized 3 alpha-hydroxysteroid dehydrogenase (3 alpha-HSD) with an elution solvent (CH3CN-MeOH-30 mM ammonium acetate, 30:30:40, v/v/v). Reduced nicotinamideadenine dinucleotide was produced on the immobilized 3 alpha-HSD column and then determined fluorometrically. Subsequently, the hydroxyapatite column was flushed with 20 mM phosphate buffer. Bile acids bound with albumin were eluted and condensed on Serumout-25. The phosphate buffer (400 mM) was finally used for the elution of bile acids bound with globulin from the hydroxyapatite column. Each condensed bile acid was eluted onto the immobilized 3 alpha-HSD column as described above.

Bile Acids and Salts↗
PubMed1989

Ectopic production of renin by ileal carcinoma.

A 54-yr-old woman with the symptoms of primary reninism, i.e. hypertension, metabolic alkalosis and elevated levels of plasma renin activity (PRA) and aldosterone, is described. She had an ileal cancer secreting active and inactive renin. The symptoms markedly improved after resection of the tumor. In the tumor active and inactive renin were proved to be present by an assay of angiotensin I formation in the presence and absence of renin antibody, and renin immunoreactivity was found immunohistochemically. The mRNA coding for the renin precursor was identified in the RNA-rich extract of the tumor by blot hybridization analysis with the human renin cDNA as a probe. The mRNA from the tumor was shown to be identical in molecular size to that from the human kidney by agarose gel electrophoresis. This is the first description of an ectopic renin-producing ileal carcinoma and the first demonstration of renin mRNA in the tumor tissue.

Carcinoma, Small Cell↗