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Biomedical subjects

H Kondo

Publications and source records attributed to H Kondo.

At least 631 records · Page 35Linked to original sources
PubMed1993

Relationship between the anti-HTLV-1 antibody level, the number of abnormal lymphocytes and the viral-genome dose in HTLV-1-infected individuals.

Two distinct diseases, adult T-cell leukemia (ATL) and HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP), develop in a minor population of HTLV-1 carriers. We examined the relationship between the viral genome dose in the peripheral-blood mononuclear cells and the serological response in HTLV-1 carriers and patients with HAM/TSP. The antibody titer to HTLV-1 gag and env proteins, as well as the frequency of an antibody response to viral protein p40tax and the titer, increased with increasing viral genome dose. However, the number of abnormal lymphocytes was not directly related to the host viral load. Patients with HAM/TSP generally showed a higher genome dose than healthy carriers and also had higher antibody titers than healthy carriers with the same HTLV-1 load, supporting the existence of an augmented immune response in these patients. These findings suggest that the antibody titer to HTLV-1 genome products, and not the number of abnormal lymphocytes, intimately reflects the approximate viral load in HTLV-1-infected individuals.

Adolescent↗
PubMed1993

Comparison of cardiac actions of doxorubicin, pirarubicin and aclarubicin in isolated guinea-pig heart.

The cardiac actions of doxorubicin were compared with those of pirarubicin and aclarubicin to understand the mechanisms responsible for differences in cardiotoxic effects of anthracycline agents. In left atrial muscle preparations obtained from guinea-pig heart and stimulated at 2 Hz, anthracyclines produced positive inotropic effects. The magnitude of the effect was pirarubicin > doxorubicin > aclarubicin. The order for depression of potentiated postrest contraction and prolongation of the time to peak twitch tension was doxorubicin > pirarubicin > aclarubicin. Drug washout following a 2-h incubation with 100 microM doxorubicin prevented a further increase in the time to peak twitch tension, caused a marked recovery of depressed potentiated postrest contractions, and augmented the positive inotropic effect. Pirarubicin and doxorubicin, but not aclarubicin, caused a parallel rightward shift of the dose-response curve for the negative inotropic effect of acetylcholine. The potency of inhibition of [3H]quinuclidinyl benzilate binding was pirarubicin > doxorubicin > aclarubicin. These results indicate that three anthracycline anticancer agents share similar effects on cardiac muscle contractility and on muscarinic acetylcholine receptors. The actions of aclarubicin were weak compared to those of doxorubicin or pirarubicin. Increases in the time to peak twitch tension and the depression of potentiated postrest contraction are apparently mediated by mechanisms different from those responsible for the positive inotropic effects or antagonism at muscarinic acetylcholine receptors.

Aclarubicin↗
PubMed1993

Developmental study of the gene expression for alpha and gamma subunits of enolase in the rat brain by in situ hybridization histochemistry.

The gene expression for alpha and gamma subunits of enolase, a dimeric enzyme in the glycolytic pathway, was examined in the developing brain of rats by in situ hybridization. The expression for the gamma subunit of enolase was first detected in post-mitotic neurons settled in the mantle zone at E13, and it increased progressively until the adult stage. Expression signals for the alpha subunit were discerned in two discrete regions showing different developmental changes: the signals in the proliferative ventricular zone were intense at E13 and decreased and eventually disappeared around birth, whereas the signals in the mantle zone persisted until the adult stage. In the adult brain, mRNAs for the alpha and gamma subunits were expressed widely in neurons, resulting in almost similar temporal patterns in the brain except for the cerebellum. Expression levels of the alpha subunit in adult glial cells were below the detection threshold of the in situ hybridization analysis. These findings suggest that both alpha and gamma enolase subunits participate in energy production in neurons of the mature brain and that marked changes in the subunit composition of enolase occur according to both neuron type and maturation.

Animals↗
PubMed1993

Expression of monocyte chemotactic and activating factor in rheumatoid arthritis. Regulation of its production in synovial cells by interleukin-1 and tumor necrosis factor.

OBJECTIVE: To investigate whether monocyte chemotactic and activating factor (MCAF) contributes to the accumulation of macrophages in the joints of patients with rheumatoid arthritis (RA). METHODS: MCAF was measured by radioimmunoassay. MCAF gene expression was determined by Northern blotting and reverse-transcriptase polymerase chain reaction. Recombinant human MCAF was injected into rabbit joints to evaluate the effect of MCAF on infiltration of macrophages. RESULTS: High levels of MCAF were detected in synovial fluid from patients with RA. Cells freshly isolated from synovial fluid expressed MCAF messenger RNA (mRNA). Fibroblast-like synoviocytes were found to express MCAF mRNA and to secrete MCAF in response to interleukin-1 (IL-1) and tumor necrosis factor in vitro. IL-1 also promoted MCAF gene expression in rabbit synovial tissue in vivo. MCAF caused marked infiltration of macrophages in rabbit synovial tissue. CONCLUSION: Our findings suggest that MCAF may contribute to the accumulation of macrophages in inflamed rheumatoid joints.

Arthritis, Rheumatoid↗
PubMed1993

Regulation of iron metabolism in HepG2 cells: a possible role for cytokines in the hepatic deposition of iron.

In chronic inflammation it is reported that serum iron is depleted and hepatic iron is increased because of reticuloendothelial system iron blockade. However, recent studies indicate that hepatic parenchymal cells increase the uptake of transferrin-bound iron after in vivo stimulation with bacterial lipopolysaccharide, suggesting that endotoxemia itself or lipopolysaccharide-induced production of inflammation-related cytokines may also be responsible for this phenomenon. In this study the actions of inflammation-related cytokines on the synthesis of iron-binding proteins (transferrin and ferritin) and transferrin receptor and the uptake of transferrin-bound iron were investigated in a human hepatoblastoma cell line, HepG2, which is the most commonly used cell line for examining the regulation of hepatic protein synthesis by cytokines. The cells were exposed to interleukin-1 beta, interleukin-6 or tumor necrosis factor-alpha separately for 24 hr. In each cytokine treatment group, the level of transferrin, which is secreted into the conditioned medium, was found to be decreased compared with that of untreated cells. On the other hand, the biosynthesis of ferritin was markedly elevated after the same treatment. This increase in ferritin by cytokine treatment was diminished when deferoxamine was used concomitantly to deplete intracellular chelatable iron. After stimulation with interleukin-1 beta, interleukin-6 or tumor necrosis factor-alpha, 59Fe-labeled transferrin uptake into the cells was increased by 36%, 48%, or 18%, respectively, and this uptake was inhibited by the addition of excess unlabeled transferrin. A binding study with 125I-labeled diferric transferrin revealed that the three cytokines increased the number of transferrin receptors on the cell surface by 1.15-fold to 1.35-fold.(ABSTRACT TRUNCATED AT 250 WORDS)

Carcinoma, Hepatocellular↗
PubMed1993

Molecular cloning of a novel isotype of Mg(2+)-dependent protein phosphatase beta (type 2C beta) enriched in brain and heart.

Two complementary DNA (cDNA) clones (pTK-1 and -2) encoding two distinct isotypes of mouse Mg(2+)-dependent protein phosphatase beta (MPP beta-1 and -2, respectively) were isolated from a melanocyte cDNA library. Although mouse pTK-1 is orthologous to the rat cDNA (JW5) reported previously [Wenk, J., Trompeter, H.I., Pettrich, K.G., Cohen, P.T.W., Campbell, D.G., and Mieskes, G. (1992) FEBS Lett. 297, 135-138], pTK-2 is a novel cDNA clone. It was strongly suggested that the pTK-1 and -2 cDNAs are splicing variants of a single pre-mRNA. The difference in the amino acid sequences between MPP beta-1 and -2 was observed only at the carboxy-terminal regions. Both the recombinant MPP beta-1 and -2 expressed in Escherichia coli cells were immunoreactive to an anti-MPP beta antibody and exhibited Mg(2+)-dependent and okadaic acid-insensitive protein phosphatase activities with similar substrate specificities. Although the mRNA of MPP beta-1 was expressed ubiquitously in various mouse tissues, that of MPP beta-2 was expressed exclusively in brain and heart. These results suggest the difference in the physiological roles of these two enzyme isotypes.

Amino Acid Sequence↗
PubMed1993

Multi-unit compartmentation of the carotid body chemoreceptor by perineurial cell sheaths: immunohistochemistry and freeze-fracture study.

The existence and extent of the perineurial cell envelope in the carotid body was clearly demonstrated by the immunoreactivity for nerve growth factor receptor (NGFR) and the freeze-fracture analysis. Consequently the chemoreceptor is regarded as multiple units, each of which consists of certain numbers of chief and sustentacular cells and nerves covered as a whole by a sheath of the perineurial cells.

Animals↗
PubMed1993

Antioxidant enzyme systems in skeletal muscle atrophied by immobilization.

To clarify the mechanism of oxidative stress in skeletal muscle atrophied by immobilization, we investigated the change of antioxidant enzyme activities in a typical slow red muscle, the soleus. Atrophied soleus muscles were collected from male Wistar rats (16 weeks old), one ankle joint of which had been immobilized in the fully extended position for 7 days. Also, soleus muscles were collected from intact age-matched rats as control. The activities of Mn-containing superoxide dismutase (Mn-SOD), Cu,Zn-containing superoxide dismutase (Cu,Zn-SOD), Se-dependent glutathione peroxidase (Se-GSHPx), glutathione S-transferase (GST), catalase, and glutathione reductase (GSSGRx) were measured. The activities of Cu,Zn-SOD, GST, and GSSGRx were significantly higher in atrophied muscles, while the others were unchanged. Increased Cu,Zn-SOD and unchanged Mn-SOD levels might reflect increased generation of superoxide anions in the cytoplasm rather than in the mitochondria. Owing to the enhancement of Cu,Zn-SOD and the unaltered Se-GSHPx and catalase activities, hydrogen peroxide is thought to be increased in the cytoplasm. Because there is also an increase of iron in the microsomes of atrophied muscles, the production of hydroxyl radicals, the most aggressive of radicals, might consequently be elevated.

Animals↗
PubMed1993

Autonomous migration of human fetal skin fibroblasts into a denuded area in a cell monolayer is mediated by basic fibroblast growth factor and collagen.

Human fetal skin fibroblasts (TIG-3S) were found to migrate into a denuded area in a cell monolayer when cultured in both serum-depleted and serum-supplemented media, unlike adult-donor skin fibroblasts which migrated well only when cultured in serum-supplemented medium. Therefore, a series of experiments was carried out to determine whether autocrine factors are involved in their migration. The migration of TIG-3S cells in serum-depleted medium was suppressed by the addition of suramin, a factor with growth factor antagonist properties, which suggests that growth factors are important for cell migration. The suramin-induced inhibition was reversed completely by adding excess basic fibroblast growth factor (bFGF) to the culture medium and partially by platelet-derived growth factor (PDGF). Treatment with neutralizing anti-PDGF antibody did not suppress TIG-3S cell migration, whereas neutralizing anti-bFGF antibody did, which indicates that bFGF is an autocrine and PDGF a paracrine factor involved in cell migration. Next, an experiment was performed to ascertain whether the extracellular matrix is involved in TIG-3S cell migration. Monensin, an inhibitor of extracellular matrix secretion, inhibited cell migration, which was reversed by adding excess type I collagen, but not excess plasma fibronectin. In addition, further evidence for the involvement of collagen was provided by the observation that ethyl-3,4-dihydroxybenzoate, a specific inhibitor of collagen synthesis, suppressed cell migration. These results suggest that the autonomous migration of TIG-3S human fetal skin fibroblasts is mediated by bFGF and type I collagen, which they produce and secrete.

Antioxidants↗
PubMed1993

Thoracoscopy for staging of lung cancer.

The recent advancements in diagnosis and treatment of thoracic disease have been made mostly in line with advancements in endoscopic equipment design and refinement of thoracoscopic surgery techniques. Between March 1992 and February 1993, video thoracoscopic procedures were performed in 50 patients. Twelve of the 50 patients were diagnosed with lung cancer. Thoracic staging was performed in 6 patients (clinical diagnosis of suspicious intrapulmonary metastasis, 3 patients; intrapulmonary metastasis and/or lymph node metastasis, 1 patient; interlobar pleural effusion, 1 patient; and pleural dissemination, 1 patient). There were no complications or mortality associated with these procedures. Our initial experience has indicated that thoracoscopic staging for lung cancer is a safe and effective procedure.

Adenocarcinoma↗
PubMed1993

Age-related changes in the mitogenic activity of heparin-binding growth factors in rat sera.

Sera from rats of either sex and different ages were examined for their ability to stimulate DNA synthesis in BALB/c 3T3 cells. The activity levels of sera from male and female rats were almost the same, with age-related changes in activity also being quite similar. Activity was considerably higher in infant rats (1-month-old), but then, at a young age (6-7 months), decreased drastically for male rats, but not significantly for female rats. It increased again in middle-aged rats (12-13 months old) and was maintained at the same level toward old age (24-26 months old) for both sexes. In order to determine what kinds of growth factors were responsible for these changes, we carried out heparin affinity chromatography on the sera of male rats. Four peaks were obtained for all sera, with individual peaks exhibiting specific age-related changes in activity. Among them a peak which was eluted at 1.1 M NaCl had very high activity. It showed a similar age-related change to that of the whole sera, except for a significant increase at old age, and the factor(s) included in the peak was found to be derived from platelets. These results suggested that the factor(s) in the peak was responsible for maintaining serum mitogenic activity at an old age. The experiments undertaken to characterize this factor suggested that it is a novel one.

Aging↗
PubMed1993

Anti-HIV (human immunodeficiency virus) activity of sulfated paramylon.

Sulfated derivatives of paramylon, a water-insoluble (1-3)-beta-D-glucan from Euglena gracilis, significantly inhibited the cytopathic effect of human immunodeficiency virus (HIV-1, HIV-2) and the expression of HIV antigen in cultured MT-4, MOLT-4 cells and human peripheral blood mononuclear cells. Native paramylon, N,N-dimethylaminoethyl paramylon, N,N-diethylaminoethyl paramylon, 2-hydroxy-3-trimethylammoniopropyl paramylon chloride, and carboxymethyl paramylon had little or no anti-HIV activity. The anti-HIV activity of the sulfated paramylon derivatives depended on the number of sulfate groups, and the molecular weight. Paramylon sulfate significantly inhibited HIV-1 binding to MT-4 cells. The anti-coagulant activity of the sulfated paramylon derivatives also depended on the number of sulfate groups, but was generally lower than that of dextran sulfate. The results point to the potential of paramylon sulfate in the treatment of HIV infection.

Animals↗
PubMed1993

The expression of rat GAP-43 cDNA in transgenic carp.

To understand more about growth-associated protein-43 (GAP-43), we produced transgenic carp by introduction of a rat GAP-43 cDNA linked to the Rous sarcoma virus-long terminal repeat into fertilized eggs. Of 180 eggs microinjected with exogenous gene, 59 embryos hatched and 4 fish were found to contain the exogenous gene sequences in the genomic DNA. From a mature female transgenic carp, parthenogenetically, 126 progeny were derived and 52 of them survived for more than 90 days. The exogenous gene sequences were detected in 22 F1 progeny, and its messenger RNA was detected in all of 10 transgenic F1 carp examined. In serum-free medium, cultured retinal ganglion cells isolated from transgenic carp elongated their axons, while non-transgenic cells did not elongate axons.

Animals↗
PubMed1993

Cloning and sequencing of a gene encoding the beta polypeptide of Ca2+/calmodulin-dependent protein kinase IV and its expression confined to the mature cerebellar granule cells.

A cDNA encoding the beta polypeptide of Ca2+/calmodulin-dependent protein kinase IV (CaM kinase IV) was isolated and sequenced from a rat cerebellar cDNA library. By in situ hybridization histochemistry, we demonstrated the differential gene expression for alpha and beta polypeptides of CaM kinase IV in mature and developing rat brains using oligonucleotide probes specific for each polypeptide.

Amino Acid Sequence↗
PubMed1993

Molecular cloning of rat cDNAs for beta and gamma subtypes of 14-3-3 protein and developmental changes in expression of their mRNAs in the nervous system.

We isolated cDNAs to beta and gamma subtypes of 14-3-3 protein, a putative regulatory protein for protein kinase C, from the brain and clarified a high homology in sequences of nucleotides and deduced amino acids between the two rat subtypes and the bovine counterparts and even reciprocally between the two rat subtypes. In Northern blot analysis, the gene expression of the two subtypes was detected weakly at E13, increased progressively after birth and reached a maximum at P7-P14. Thereafter it decreased slightly. In situ hybridization analysis allowed detection of the beta but not the gamma subtype in the matrix cells of the ventricular germinal zone of the neural wall. In post-mitotic neurons in the mantle zone and maturing brain loci, genes of the two subtypes were expressed in patterns similar to each other, and three neuron types were identified: type I neurons with high levels of expression throughout development; type II neurons showing high expression during the early developmental stages with a subsequent decrease in the expression at maturing and adult stages; and type III neurons showing consistently low levels of expression throughout development. The wider and more highly-patterned expression of the 14-3-3 protein family than expected suggests that this protein may be involved in the elaborate regulation of some fundamental cellular activities and differentiation of neurons.

14-3-3 Proteins↗
PubMed1993

Differential expression of mRNAs encoding gamma and delta subunits of Ca2+/calmodulin-dependent protein kinase type II (CaM kinase II) in the mature and postnatally developing rat brain.

The expression of mRNAs encoding gamma and delta subunits of Ca2+/calmodulin-dependent protein kinase type II (CaM kinase II) in the brain of mature and postnatally developing rats was examined by in situ hybridization histochemistry. At the adult stage, mRNAs for both subunits were expressed in the olfactory bulb, and piriform cortex. The cerebral neocortex expressed the gamma subunit mRNA evenly through the layers II to VI at a moderate level, whereas the delta subunit mRNA was expressed in a distinctly laminar distribution. The hippocampal pyramidal and dentate granule cells expressed the gamma subunit mRNA intensely without any significant expression signals for the delta subunit. In the cerebellum, moderate expression signals for the gamma subunit were confined to the Purkinje cell layer, while intense expression signals for the delta subunit were detected in the cerebellar granule cell layer, without any significant expression signals in the Purkinje cell layer. In the spinal cord, mRNA for the gamma subunit was expressed in neurons throughout the gray matter, while the expression of mRNA for the delta subunit was confined to neurons in laminae I and IX. The expression pattern of genes for both subunits was basically accomplished at birth with lower intensity, except for the striatum and cerebellar Purkinje cells, which transiently expressed mRNA for the gamma and delta subunits, respectively, at birth. These results indicate that the expression of genes for each of the subunits of CaM kinase II is differentially regulated in various brain regions and that the individual subunits are involved in differential functions in mature and developing rat brain.

Animals↗
PubMed1993

Pathological changes in epidemic porcine Pneumocystis carinii pneumonia.

An outbreak of epidemic porcine Pneumocystis carinii pneumonia on a "farrow-to-finish" pig farm was examined. The clinical disease was observed in weanling piglets, mostly in the seventh to eleventh weeks of life. Lesions of P. carinii pneumonia were detected histologically in the pigs at 36 to 75 days of age. These included pulmonary septal thickening, with mononuclear cell infiltration, swelling of the alveolar lining, an intra-alveolar exudate and the presence of P. carinii organisms. Focal pneumonia was seen at 36-43 days of age and diffuse pneumonia at 46-75 days. This outbreak resembled the infantile epidemic form of P. carinii pneumonia in man, in being age-related and in causing a non-suppurative intense inflammatory response in the lungs.

Animals↗