Publications by authors named "Nishihara M"

A repeat-injection of polyethylene glycol-modified liposomes (PEGylated liposomes) causes a rapid clearance of them from the blood circulation in certain cases that is referred to as the accelerated blood clearance (ABC) phenomenon. In the present study, we examined whether polymeric micelles trigger ABC phenomenon or not. As a preconditioning treatment, polymeric micelles (9.

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Type-I ribosome-inactivating protein (RIP), which is found in many plants, catalyzes depurination of a specific adenine in the sarcin/ricin domain (SRD) of the large rRNA causing loss of ribosomal activity. Previously, we found a RNA apurinic site-specific lyase (RALyase) that catalytically cleaved the phosphodiester bond at the RIP-dependent depurination site by beta-elimination reaction. Here we show that both the RIP activity and RIP-RALyase-mediated cleavage of SRD in the cytoplasmic ribosome were induced at the late stage of senescence of wheat coleoptiles.

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Blue-flowered gentian (Gentiana triflora) is known to accumulate gentiodelphin, a unique polyacylated delphinidin-type anthocyanin, in the petals. Almost all of the structural genes involved in gentiodelphin biosynthesis have been isolated, but an important gene encoding UDP-glucose:anthocyanin 5-O-glucosyltransferase (5GT) remained to be identified. In this study, an attempt was made to isolate and characterize gentian 5GT, which is responsible for glucosylation of anthocyanidin 3-glucoside.

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Various radiation-induced tumors, including meningioma, glioma, and sarcoma, have been reported; however, metachronous intracranial double tumors induced by radiation therapy are extremely rare. A 1-year-old boy had undergone tumor removal and craniospinal radiation therapy (30 Gy) for cerebellar medulloblastoma. At 24 years old, parasagittal meningioma developed in the left parietal region and was totally removed.

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It is well known that the release of glucocorticoids from the adrenal gland is increased in response to many types of stressors and plays a principal role in stress responses. We have shown that the synthesis of prostaglandins (PGs) in the brain is increased under several stress conditions including immobilization (IMO), and that endogenous glucocorticoids counteract this stress-induced PG synthesis. It was also recently reported that IMO damages dopaminergic (DA) neurons in the substantia nigra (SN), which is known to cause symptoms similar to Parkinson's disease (PD).

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Phospholipase A1 is a hydrolytic enzyme that catalyzes the removal of the acyl group from position 1 of glycerophospholipids to form 2-acyl lysophospholipids. Lysophospholipids are used in foods, cosmetics, and pharmaceuticals as surfactants. Novel forms of phospholipase A1 that function at low temperatures are desirable for use in lipophilic systems in food processing.

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Background: The fibrotic process in airway remodeling of asthma may be characterized by an exaggerated deposition of extracellular matrix (ECM) components such as fibronectin and type I, III and IV collagen. In the present study, we established airway remodeling model mice and examined the mechanism of fibrotic change by measuring chemotactic activity of lung fibroblasts and quantifying collagen content in lung tissues.

Methods: Airway remodeling model mice were made by ovalbumin (OA) sensitization and inhalation.

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The role of parathyroid hormone-related peptide (PTHrP) in the regulation of hypercalcemia in patients with malignancies is well studied, but whether its expression in tumor tissue correlates with tumor progression is not clear at present. The majority of tumors that metastasize to the bone produce PTHrP, and PTHrP expression correlates with skeletal localization of tumors. About 95% of colorectal adenocarcinomas overexpress PTHrP mRNA and protein, and the expression level is higher in poorly differentiated than in well-differentiated adenocarcinomas.

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The importance of connexins is implicated in proliferation and differentiation of cells. In skeletal muscle cells, connexin43 (Cx43) has been identified as the major connexin, and gap-junctional communication mediated by connexins has been shown to be required for their myogenic differentiation. In addition, inhibition of connexin function has been shown to induce transdifferentiation of osteoblasts to an adipocytic phenotype.

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Recently we found that the level of anti-infarct tolerance afforded by ischemic preconditioning (IPC) and erythropoietin (EPO) infusion was closely correlated with the level of Ser9-phospho-GSK-3beta upon reperfusion in the heart. To get an insight into the mechanism by which phospho-GSK-3beta protects the myocardium from ischemia/reperfusion injury, we examined the effects of IPC and EPO on interactions between GSK-3beta and subunits of the mitochondrial permeability transition pore (mPTP) in this study. Rat hearts were subjected to 25-min global ischemia and 5-min reperfusion in vitro with or without IPC plus EPO infusion (5 units/ml) before ischemia.

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Sexual differentiation of the brain in rodents is achieved by estrogens, which are converted from androgens in the brain, during the perinatal period. We have identified the progranulin (PGRN) gene as one of the sex steroid-inducible genes that may be involved in masculinization of the rat brain. In the present study, we generated a line of mice with targeted disruption of the PGRN gene, and investigated male sexual behaviour, aggression and anxiety.

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Orange- to red-colored flowers are difficult to produce by conventional breeding techniques in some floricultural plants. This is due to the deficiency in the formation of pelargonidin, which confers orange to red colors, in their flowers. Previous researchers have reported that brick-red colored flowers can be produced by introducing a foreign dihydroflavonol 4-reductase (DFR) with different substrate specificity in Petunia hybrida, which does not accumulate pelargonidin pigments naturally.

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The aim of this study was to examine the hypothesis that delta-opioid receptor activation before ischemia suppresses gap junction (GJ) permeability by PKC-mediated connexin 43 (Cx43) modulation, which contributes to infarct size limitation afforded by the delta-opioid receptor activation. A delta-opioid receptor agonist, [D-Ala(2),D-Leu(5)]-enkephalin acetate (DADLE, 300 nM), was used in place of preconditioning (PC) ischemia to trigger PC mechanisms in rat hearts. GJ permeability during ischemia, which was assessed by Lucifer yellow, was reduced by DADLE to 47% of the control level, and this effect of DADLE was almost abolished by a PKC-epsilon inhibitor [PKC-epsilon translocation inhibitory peptide (PKC-epsilon-TIP)] but was not affected by a PKC-delta inhibitor (rottlerin).

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IL-17-producing Th (Th17) comprise a distinct lineage of pro-inflammatory Th that are major contributors to autoimmune diseases. Treatment with IL-6 and transforming growth factor beta (TGFbeta) induces naive CD4+ T cells to generate Th17, which also requires expression of the IL-6/TGFbeta target RORgammat. We reported that IL-6 transduces two signaling pathways via tyrosine redidues of the signal transducer gp130: one depends on signal transducers and activators of transcription (STAT)-3 activation and the other on Src homology region 2 domain-containing phosphatase 2 (SHP2)/Grb2 associated binder (Gab)/mitogen-activated protein kinase (MAPK) activation.

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Article Synopsis
  • In the corpus luteum of rats and mice, 20alpha-hydroxysteroid dehydrogenase (20alpha-HSD) converts progesterone to the inactive metabolite 20alpha-dihydroprogesterone, playing a role in luteolysis.
  • Researchers created a mouse strain lacking the 20alpha-HSD gene and found that these mice had no 20alpha-HSD activity and prolonged estrous cycles and pregnancies.
  • Despite lower serum progesterone, the absence of 20alpha-HSD led to fewer pups being born and fewer live births, indicating its minor role in luteolysis but importance in newborn survival.
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The present study was conducted to investigate whether goat fetal myoblasts with no inherent adipogenic potential can be induced to transdifferentiate into adipocytes. Goat fetal myoblasts were transiently transfected by the adipogenic transcription factors, peroxisome proliferator-activated receptor-gamma (PPARgamma) and CCAAT/enhancer-binding protein-alpha (C/EBPalpha). Both PPARgamma and C/EBPalpha were capable of inducing adipogenic transdifferentiation as indicated by the appearance of mature adipocytes when the transfected cells were cultured in adipogenic differentiation medium (ADM).

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To establish a model system for alteration of flower color by carotenoid pigments, we modified the carotenoid biosynthesis pathway of Lotus japonicus using overexpression of the crtW gene isolated from marine bacteria Agrobacterium aurantiacum and encoding beta-carotene ketolase (4,4'-beta-oxygenase) for the production of pink to red color ketocarotenoids. The crtW gene with the transit peptide sequence of the pea Rubisco small subunit under the regulation of the CaMV35S promoter was introduced to L. japonicus.

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We encountered an unusual case of hyperparathyroidism with both hemosiderin deposits on the ribs and low intensity on T2-weighted magnetic resonance imaging (MRI) caused by a parathyroid adenoma with multiple brown tumors that mimicked metastatic bone tumor due to false positive results on computed tomography (CT) and Tc-99m sestamibi (MIBI) imaging. The patient, a middle-aged woman, had very high serum levels of calcium (14.1 mg/dl), alkaline phosphatase (9,369 IU/l) and intact-PTH (12,400 pg/ml), and a large tumor (2.

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Prefrontal cortex (PFC) dopamine D1/5 receptors modulate long- and short-term neuronal plasticity that may contribute to cognitive functions. Synergistic to synaptic strength modulation, direct postsynaptic D1/5 receptor activation also modulates voltage-dependent ionic currents that regulate spike firing, thus altering the neuronal input-output relationships in a process called long-term potentiation of intrinsic excitability (LTP-IE). Here, the intracellular signals that mediate this D1/5 receptor-dependent LTP-IE were determined using whole cell current-clamp recordings in layer V/VI rat pyramidal neurons from PFC slices.

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Recent studies have demonstrated the presence of neurogenesis in the adult mammalian hippocampus, and it has been suggested that estrogen and various growth factors influence the processes of adult neurogenesis. The present study assessed cell proliferation in the dentate gyrus and the mRNA expression levels of granulin, insulin-like growth factor-I (IGF-I), and brain-derived neurotrophic factor (BDNF) in the hippocampus 4 h after treatment with estradiol benzoate (EB) in 3- and 12-month old ovariectomized rats. At 3 months of age, mRNA expression of granulin precursor and cell proliferation were increased by EB treatment, although the mRNA expressions of IGF-I and BDNF remained unchanged.

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Gonadotropin-releasing hormone (GnRH) neurons arise in the olfactory placode, migrate into the preoptic area (POA), and then extend axons to the median eminence during embryogenesis. Little information is available concerning the properties of GnRH neurons during the late gestational period when GnRH neurons reach the POA and form neuronal networks, although many studies have examined such properties during earlier developmental stages or the postnatal period. The present study was performed to elucidate the involvement of gamma-aminobutyric acid (GABA), one of the major neurotransmitters modifying GnRH neural activity, in regulation of GnRH gene expression on embryonic day 18.

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Intrauterine infection is associated with chorioamnionitis (CAM), which can lead to preterm delivery. We previously reported that the levels of IgM and the incidence of CAM were elevated in preterm infants with neonatal pulmonary emphysema. The pathogen and target of this IgM remain unclear.

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We have previously produced human growth hormone (hGH) transgenic (TG) rats that show low circulating levels of both hGH and endogenous rat GH. Although body length of the TG rats is normal, they develop hyperphagia and severe obesity. The present study was undertaken to elucidate the causes of hyperphagia in the TG rats by focusing on temporal changes in plasma ghrelin levels and hypothalamic neuropeptide Y (NPY) contents.

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The aims of the present study were to establish a culture system for goat skeletal muscle stem cells and to examine their myogenic and adipogenic properties in vitro. Cells were isolated from the skeletal muscle of the Shiba goat and cultured in vitro. Most of the cells were positive for myogenic markers, such as Pax7, MyoD, and desmin, and immunocytochemistry revealed they differentiated to form myotubes expressing myosin heavy chain, indicating they were highly myogenic.

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We report the systematic elaboration of a cost-effective, interference-minimized assay for the label-free optical transduction of chemical reactions. Recently, we have found that certain complexes formed by arginine-rich cell-penetrating peptides (CPPs) and amphiphilic counteranions can act as synergistic anion carriers in lipid bilayer membranes. Application of this discovery to rapid and reversible cytosolic CPP delivery has been described (Futaki, S.

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