Akinori Shimada

Gifu Pharmaceutical University, Gifu-shi, Gifu-ken, Japan

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Publications (63)140.37 Total impact

  • Article: Relationship of angiogenesis and microglial activation to seizure-induced neuronal death in the cerebral cortex of Shetland Sheepdogs with familial epilepsy.
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    ABSTRACT: Objective-To determine whether angiogenesis and microglial activation were related to seizure-induced neuronal death in the cerebral cortex of Shetland Sheepdogs with familial epilepsy. Animals-Cadavers of 10 Shetland Sheepdogs from the same family (6 dogs with seizures and 4 dogs without seizures) and 4 age-matched unrelated Shetland Sheepdogs. Procedures-Samples of brain tissues were collected after euthanasia and then fixed in neutral phosphate-buffered 10% formalin and routinely embedded in paraffin. The fixed samples were sectioned for H&E staining and immunohistochemical analysis. Results-Evidence of seizure-induced neuronal death was detected exclusively in samples of cerebral cortical tissue from the dogs with familial epilepsy in which seizures had been observed. The seizure-induced neuronal death was restricted to tissues from the cingulate cortex and sulci surrounding the cerebral cortex. In almost the same locations as where seizure-induced neuronal death was identified, microvessels appeared longer and more tortuous and the number of microvessels was greater than in the dogs without seizures and control dogs. Occasionally, the microvessels were surrounded by oval to flat cells, which had positive immunohistochemical results for von Willebrand factor. Immunohistochemical results for neurons and glial cells (astrocytes and microglia) were positive for vascular endothelial growth factor, and microglia positive for ionized calcium-binding adapter molecule 1 were activated (ie, had swollen cell bodies and long processes) in almost all the same locations as where seizure-induced neuronal death was detected. Double-label immunofluorescence techniques revealed that the activated microglia had positive results for tumor necrosis factor-α, interleukin-6, and vascular endothelial growth factor receptor 1. These findings were not observed in the cerebrum of dogs without seizures, whether the dogs were from the same family as those with epilepsy or were unrelated to them. Conclusions and Clinical Relevance-Signs of angiogenesis and microglial activation corresponded with seizure-induced neuronal death in the cerebral cortex of Shetland Sheepdogs with familial epilepsy. Microglial activation induced by vascular endothelial growth factor and associated proinflammatory cytokine production may accelerate seizure-induced neuronal death in dogs with epilepsy.
    American Journal of Veterinary Research 05/2013; 74(5):763-70. · 1.27 Impact Factor
  • Article: Ultrastructural changes in the air-blood barrier in mice after intratracheal instillations of Asian sand dust and gold nanoparticles.
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    ABSTRACT: The purpose of this study was to investigate a possible translocation pathway of intratracheally instilled gold nanoparticles after the induction of acute pulmonary injury by Asian sand dust. ICR mice were intratracheally instilled with 800μg Asian sand particles (CJ-2 particles) 24h before instillation of 50-nm gold nanoparticles. Lungs from mice treated with Asian sand particles and gold nanoparticles showed an acute focal inflammation with an increased expression of proinflammatory cytokines (IL-6 and TNF-α) and oxidative stress markers (Cu/Zn SOD and iNOS) in alveolar macrophages, type I alveolar epithelial cells, and endothelial cells at the alveolar walls. Electron microscopy revealed a destruction of the alveolar walls with an increased number of endocytic vesicles in the cytoplasm of both type I epithelial cells and endothelial cells; gold nanoparticles were demonstrated in these endocytic vesicles. These findings suggest that translocation of the exposed nanoparticles may be enhanced in the lung tissues with acute inflammatory changes.
    Experimental and toxicologic pathology: official journal of the Gesellschaft fur Toxikologische Pathologie 04/2013; · 1.43 Impact Factor
  • Article: Vanadium Toxicity in Mice: Possible Impairment of Lipid Metabolism and Mucosal Epithelial Cell Necrosis in the Small Intestine.
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    ABSTRACT: Because precise information as to the toxicity of vanadium is required for practical use of vanadium compounds as antidiabetic drugs, we examined vanadium toxicity in mice fed normal diet or high-fat diet (C57BL/6N, male, 7 weeks) by oral administration of ammonium metavanadate (AMV) with a maximum dose of 20 mgV/kg/day. Marked lipid accumulation in hepatocytes, renal epithelial cells, and mucosal epithelial cells of the small and large intestines and severe degeneration, necrosis, and loss of mucosal epithelial cells in the small intestine were observed. These pathological changes were more severe in mice fed high-fat diet than mice fed normal diet, and the intensity of the changes increased with increase in the administered dose of AMV. By electron microscopy, the number and size of lipid droplets in hepatocytes were increased. In the small intestine, a TUNEL assay showed a decreased number of positive cells, and positive cells for acrolein immunohistochemistry were observed specifically in the mucosal epithelial cells indicating degeneration and necrosis in the AMV-treated group, suggesting that a possible factor responsible for cell necrosis in the small intestine could be oxidative stress. In conclusion, AMV may impair cellular lipid metabolism, resulting in lipid accumulation, and induce mucosal epithelial cell necrosis in the small intestine.
    Toxicologic Pathology 12/2012; · 1.91 Impact Factor
  • Article: Caveolae-mediated Endocytosis of Intratracheally Instilled Gold Colloid Nanoparticles at the Air-Blood Barrier in Mice.
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    ABSTRACT: Endocytosis is the primary mechanism by which nanoparticles are translocated over the alveolar epithelium. The purpose of this study was to elucidate the association between endocytosis and the translocation of nanoparticles at the air-blood barrier (ABB). Gold colloid particles (diameter, 20 nm) were intratracheally instilled into male ICR mice. Fifteen minutes after instillation, localized accumulation of agglomerated gold particles was observed in the cytoplasm of macrophages, on the surface of alveolar epithelial cells (AECs), and in alveoli. Electron microscopy revealed particles in the vesicles of macrophages, on the surface of AECs, and in caveolae-like vesicles in type 1 AECs. Immunohistochemistry demonstrated positive immunolabeling for caveolin-1 in the ABB of untreated lungs as well as lungs treated with gold particles. Double immunofluorescence and immunoelectron microscopy revealed the presence of caveolin-1 in AECs in the untreated lungs. These results suggest that instilled gold colloid particles are internalized into the alveolar epithelium at the ABB by caveolae-mediated endocytosis, which is regarded as a physiological function of AECs.
    Toxicologic Pathology 08/2012; · 1.91 Impact Factor
  • Article: Metallothionein deficiency exacerbates chronic inflammation associated with carcinogenesis in stomach of mice infected with Helicobacter pylori.
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    ABSTRACT: Metallothionein (MT), a low-molecular-weight protein with a high affinity for divalent heavy metal ions, is involved in many pathophysiological processes, including metal homeostasis, detoxification, cell proliferation and protection against oxidative damage. We previously found that MT in gastric mucosa plays a role in protecting against Helicobacter pylori (H. pylori)-induced gastritis at the early stage of infection. H. pylori-induced chronic gastric inflammation is shown to be associated with gastric carcinogenesis. Thus, to examine whether gastric MT contributes to protection against H. pylori-induced chronic inflammation, we compared histological changes in the gastric mucosa of MT-null and the wild-type mice at 53 weeks after inoculation three times with H. pylori SS1. As a result, we observed disruption of the gastric mucosa in MT-null mice, but not in the wild-type mice, even at the late stage of H. pylori-infection. Evaluation of pathological changes in gastric specimens by the updated Sydney grading system revealed that scores related to chronic inflammation and polymorphonuclear cell activity were higher in infected MT-null mice than those in the wild-type mice. Furthermore, a higher score for metaplasia was also observed in the MT-null stomach. These results suggested that MT might be involved in protecting against H. pylori-induced gastric chronic inflammation associated with carcinogenesis.
    The Journal of Toxicological Sciences 01/2012; 37(6):1261-5. · 1.52 Impact Factor
  • Article: Cerebral vascular hamartoma with thrombosis in a dog.
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    ABSTRACT: A cerebral vascular hamartoma was identified in the frontal lobe, striatum and thalamus of the right side of the brain of a male, 7-year-old Shih Tzu. Histologically, the lesion consisted of thin-walled vessels, which showed various sizes and occasionally contained fibrin thrombi. These vascular walls were composed of a single layer of fibromuscular tissue lined by flat endothelium with various amount of collagen, but devoid of large coat of smooth muscles and elastic tissue. Immunohistochemically, the lining endothelial cells were positive for von Willebrand Factor antibody. Neuropil between the vessels was stained with Klüver-Barrera stain, and positive for synaptophysin and GFAP antibodies. Based on these findings, the lesion was diagnosed as vascular hamartoma, which might resemble venous malformation in humans.
    Journal of Veterinary Medical Science 06/2011; 73(10):1367-9. · 0.85 Impact Factor
  • Article: Cadmium toxicity is caused by accumulation of p53 through the down-regulation of Ube2d family genes in vitro and in vivo.
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    ABSTRACT: Cadmium (Cd) causes renal dysfunction with damage to kidney proximal tubule cells; however, the precise mechanisms of the toxicity remain unclear. Previously, we found that the expression of Ube2d4 gene, which is a member of the ubiquitin-conjugating enzyme Ube2d family, is suppressed by Cd in NRK-52E rat renal tubular epithelial cells. To investigate the mechanisms of Cd-induced renal toxicity, we examined the effects of Cd on the ubiquitin-proteasome system, particularly the expression and function of Ube2d family members in the NRK-52E cells and mice. Cd markedly decreased the expression of Ube2d1, Ube2d2, Ube2d3 and Ube2d4 prior to the appearance of cytotoxicity in the NRK-52E cells. Cd also dramatically increased p53 protein levels in the cells, without stimulation of p53 gene expression or inhibition of proteasome activity. In addition, Cd induced phosphorylation of p53 and caused apoptosis in the NRK-52E cells. In vivo, we examined the effect of orally administrated Cd for 12 months on the expression of Ube2d genes and accumulation of p53 in the mouse kidney. Chronic Cd exposure also caused suppression of Ube2d genes expression and accumulation of p53. Cd did not induce severe kidney injury, but caused apoptosis in the renal tubules. These results suggest that the Cd-induced accumulation of p53 may be due to inhibition of p53 degradation through the down-regulation of Ube2d family genes, and that Cd induces p53-dependent apoptosis in renal tubular cells. Moreover, Ube2d family members may be one of the critical targets of renal toxicity caused by Cd.
    The Journal of Toxicological Sciences 01/2011; 36(2):191-200. · 1.52 Impact Factor
  • Article: Experimental Scuticociliatosis in Japanese flounder (Paralichthys olivaceus) infected with Miamiensis avidus: pathological study on the possible neural routes of invasion and dissemination of the scuticociliate inside the fish body.
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    ABSTRACT: Japanese flounder (Paralichthys olivaceus) were experimentally infected with the highly pathogenic scuticociliate Miamiensis avidus (syn. Philasterides dicentrarachi) using the immersion method to clarify/identify the possible neural routes of entry and possible ways of dissemination of the scuticociliate in the fish body. Scuticociliates were observed on the skin and gills right from day 0-1 post-infection, muscle tissue on day 2 post-infection, reached the brain, and spinal cord on day 3 post-infection, and systemic infection was prominent afterwards. Brain lesions were observed in most of the examined fish from days 3 and 4 post-infection and considered to be the cause of the sudden increase in mortality. Affected fish showed varying degrees of tissue damage including severe epidermal and dermal necrotic lesions, necrotic myositis, encephalitis and myelitis. Whereas, scuticociliates were frequently observed along the optic and/or olfactory nerve in the fish which were accompanied by severe brain lesions but by minimum lesions in the gills and skin, suggesting that in addition to skin and/or gills, neural routes including periorbital and nasal routes may play a role in scuticociliate invasion to the brain. Scuticociliates were also observed in the peripheral nerve fibers in the muscle tissue, cranial and spinal nerves, cranial cavity and in the vertebral canal, suggesting that nerve fibers and/or cerebrospinal fluid circulation may be involved in the spread of the scuticociliate throughout the body in addition to the blood circulation and connective tissue.
    Journal of Veterinary Medical Science 12/2010; 72(12):1557-63. · 0.85 Impact Factor
  • Article: Attenuation of cadmium-induced testicular injury in metallothionein-III null mice.
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    ABSTRACT: In order to evaluate the role of metallothionein (MT)-III in cadmium (Cd)-induced testicular toxicity, we examined the sensitivity of MT-III null mice to severe testicular injury caused by Cd. Male MT-III null mice, MT-I/II null mice and wild-type mice were given a subcutaneous injection of CdCl(2) (15μmol/kg). The testis was collected from each mouse at 6, 12 and 24h after Cd administration. Testicular hemorrhages by evaluating morphology, hemoglobin content and histological parameters in the 3 types of mice were elevated by Cd injection in a time-dependent manner. The degree of hemorrhage in Cd-injected MT-I/II null mice was similar to that in the wild-type mice. In contrast, hemorrhage in the MT-III null mice was attenuated compared with that in wild-type mice and MT-I/II null mice. Cd levels, MT-I and MT-II mRNA levels and Cd-binding molecules in the testis were similar between MT-III null mice and wild-type mice. In microarray analysis, high expression of purine-nucleoside phosphorylase 2 (Pnp2), retinal degeneration 3 (Rd3), and cadherin-like 24 (Cdh24) was revealed in the testis of MT-III null mice under normal or Cd-treated conditions. MT-III null mice were found to show attenuation of Cd-induced severe testicular toxicity. These results suggest the lack of MT-III contributes to protection of testis from Cd. In addition, regulation of Pnp2, Rd3, and Cdh24 mRNA levels may involve the sensitivity of MT-III null mice to Cd.
    Life sciences 10/2010; 87(17-18):545-50. · 2.56 Impact Factor
  • Article: Pathological study of acute pulmonary toxicity induced by intratracheally instilled Asian sand dust (kosa).
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    ABSTRACT: The objective of this study was to investigate acute lung toxicity caused by Asian sand dust. Simulated Asian sand dust collected from the Tennger desert in China (CJ-2 particles) and Asian sand dust collected from the atmosphere in Japan (Tottori particles) were used. Saline suspensions of 50, 200, 800, and 3,000 µg Asian sand dust were intratracheally instilled to ICR mice. Localized accumulation of the dust particles was observed in the bronchioles and the alveoli of the lung tissues; acute inflammatory changes characterized by infiltration of macrophages and neutrophils were observed around the particles. Degenerated alveolar walls and bronchial epithelial cells, as well as a weakened positive immunolabeling for laminin, were observed to be associated with particle attachment. Positive immunolabelings for interleukin-6, tumor necrosis factor-α inducible nitric oxide synthase, and dimeric copper- and zinc-containing superoxide dismutase were observed mainly in the inflammatory cells in the lesions; these findings were not observed in the controls or in areas lacking lesions. These results suggest that Asian sand dust particles caused damage to the lung tissue through a direct physical effect. In addition, secondary released cytokines and oxidative stress generated in the lesion may be involved in the development of the acute lung toxicity.
    Toxicologic Pathology 09/2010; 38(7):1099-110. · 1.91 Impact Factor
  • Article: Pathological study on the scuticociliatosis affecting farmed Japanese flounder (Paralichthys olivaceus) in Japan.
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    ABSTRACT: Pathological findings associated with scuticociliatosis in farmed Japanese flounder in Japan are described. Ten moribund fishes, farmed in Tottori Prefectural Fisheries Experimental Station, showed cutaneous ulcers, darkened skin, fin and tail rot, exophthalmia and alterations in swimming behaviour. Histopathologically, severe epidermal degeneration and necrosis, hyperplasia of branchial epithelium, myositis, myelitis, encephalitis associated with heavy accumulation of scuticociliates in the periorbital cavity and optic nerve fiber were observed. Moreover, masses of ciliates were found to feed on the host tissues such as skeletal muscles, gills and brain, causing severe degenerative changes associated with abundant neutrophilic and lymphocytic infiltration. These findings suggest that the present scuticociliate, Miamiensis avidus, is a highly invasive and destructive pathogen infecting Japanese flounder and capable of developing systemic fatal infection.
    Journal of Veterinary Medical Science 05/2010; 72(10):1359-62. · 0.85 Impact Factor
  • Article: Resistance of metallothionein-III null mice to cadmium-induced acute hepatotoxicity.
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    ABSTRACT: We examined the sensitivity of metallothionein (MT)-III null mice to cadmium (Cd)-induced acute hepatotoxicity. MT-I/II null mice were also used to compare Cd toxicities between MT-III null mice and MT-I/II null mice. Male MT-I/II null mice, MT-III null mice and wild-type mice were given s.c. injection of Cd (5-20 micromol/kg) and then the blood and liver were collected from each mouse under ether anesthesia at 2 days after the administration. Serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities elevated by injection of Cd were significantly higher in the MT-I/II null mice than in the wild-type mice. In the MT-III null mice, ALT and AST activities were not elevated following the injection of Cd. Further, marked morphological changes such as necrosis of hepatocytes, severe hemorrhage and congestion were observed by injection of Cd in both MT-I/II null mice and wild-type mice, whereas the degree of injury was found to be more extensive in MT-I/II null mice. In contrast, only occasional damage was observed in the liver of MT-III null mice treated with the same dose of Cd. These morphological observations were consistent with the results of ALT and AST activities. In the present study, it was clearly found that MT-III null mice were resistant to Cd hepatotoxicity, although MT-I/II null mice were sensitive to its toxicity. MT-III may be an accelerative factor in Cd-induced acute hepatotoxicity.
    The Journal of Toxicological Sciences 01/2010; 35(2):209-15. · 1.52 Impact Factor
  • Article: Involvement of metallothionein (MT) as a biological protective factor against carcinogenesis induced by benzo[a]pyrene (B[a]P).
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    ABSTRACT: The purpose of this study was to examine whether intracellular metallothionein (MT) protects against benzo[a]pyrene (B[a]P)-induced forestomach and lung carcinogenesis. Ten-week-old male MT-I/II null mice and wild-type mice were orally administered B[a]P at a dose of 100 or 250 mg/kg twice a week for 4 weeks. B[a]P-induced mortality was higher in the MT-I/II null mice than in the wild-type mice. The incidence of tumors in the forestomach and lung was 78.6% and 7.1% in the wild-type mice treated with 100 mg/kg B[a]P, respectively. In the MT-I/II null mice treated with B[a]P, tumor incidence in the forestomach and lung was 100% and 33.3%, respectively. The tumor area in the forestomach and lung in the MT-I/II null mice treated with B[a]P was greater than that of wild-type mice. These results suggest that MT acts as a biological protective factor against carcinogenesis induced by B[a]P.
    The Journal of Toxicological Sciences 01/2010; 35(2):225-30. · 1.52 Impact Factor
  • Article: Protective role of metallothionein in benzo[a]pyrene-induced DNA damage.
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    ABSTRACT: Metallothionein (MT) is known to reduce chemical carcinogenesis. Carcinogenesis induced by benzo[a]pyrene (B[a]P) which is an environmental chemical carcinogen is related to DNA adduct formation and oxidative damage through metabolic activation. Ten-week-old male MT-I/II null mice and wild-type mice were given a single injection of B[a]P (250 mg/kg, p.o.), and B[a]P-induced DNA damage was evaluated at 6-48 hr later. The frequencies of micronucleated reticulocytes (MNRET) in MT-I/II null mice were significantly increased compared with that of wild-type mice at 48 hr after B[a]P administration. At 48 hr after B[a]P administration, comet scores were significantly increased in MT-I/II null mice but not in wild-type mice. 8-Hydroxy-2'-deoxyguanosine (8-OHdG), a biomarker of oxidative DNA damage, was significantly increased in liver of MT-I/II null mice at 6 and 12 hr after B[a]P administration, although that of wild-type mice was only slightly changed. Because cytochrome P450 (CYP) plays a major role in the process of B[a]P metabolic activation, we attempted to reveal the effect of MT on metabolic activation of B[a]P. Although CYP1A activities were elevated in the livers of MT-I/II null mice and wild-type mice treated with B[a]P, it was not different between both strains of mice. In addition, MT levels in the livers of wild-type mice were significantly increased by the B[a]P treatment, whereas MT was not detected in livers of MT-I/II null mice with or without B[a]P treatment. These results demonstrate that MT acts as an endogenous defensive factor against B[a]P-induced DNA damage.
    The Journal of Toxicological Sciences 10/2009; 34(5):449-58. · 1.52 Impact Factor
  • Article: Lymphoepithelial thymoma characterized by proliferation of spindle cells in a Samoyed dog.
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    ABSTRACT: Lymphoepithelial thymoma was diagnosed in a 14-year-old Samoyed dog with clinical symptoms of myasthenia gravis at 6 months of age. At necropsy, dark red-colored mass with many nodular protuberances was found in the anterior mediastinal area. Histologically, the mass consisted of solid proliferation of neoplastic cells with spindle nuclei and cytoplasm and a few lymphocytes, which is separated by an abundant fibrous and adipose tissue. Immunohistochemically, spindle cells were positive for cytokeratin, and infiltrating lymphocytes were positive for CD3. On the basis of these findings, this tumor was diagnosed as lymphoepithelial thymoma, which is morphologically similar to type A thymoma in humans.
    Journal of Veterinary Medical Science 09/2009; 71(9):1265-7. · 0.85 Impact Factor
  • Article: Translocation pathway of the intratracheally instilled C60 fullerene from the lung into the blood circulation in the mouse: possible association of diffusion and caveolae-mediated pinocytosis.
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    ABSTRACT: Ultrafine particles are ubiquitous in ambient urban and indoor air from multiple sources and may contribute to adverse respiratory and cardiovascular diseases. Recently, it has been demonstrated that ultrafine particles (UFPs) are translocated from the lung into the systemic circulation. The exact pathway, however, for the translocation in the lung remains unclear. In this study, we examined the translocation pathway of intratracheally instilled C60 fullerene particles from the lung into the blood circulation in the mouse. Using light microscopy, aggregated particles of fullerene were observed in the capillary lumen in the lung and the pulmonary lymph nodes immediately after instillation. Electron microscopic analysis demonstrated an increased number of pinocytotic vesicles (caveolae) of various sizes in the type 1 alveolar epithelial cells (AEC) and endothelial cells; occasional caveolae containing some particulate substances were observed. In addition, particles of various sizes were observed throughout the structure of the air-blood barrier (ABB). These findings suggest that fullerene particles may pass the ABB by both diffusion and caveolae-mediated pinocytosis, resulting in immediate translocation into the systemic circulation.
    Toxicologic Pathology 05/2009; 37(4):456-62. · 1.91 Impact Factor
  • Article: Distribution of the inflammatory lesions in the central nervous system of dogs affected with disseminated and ocular form of granulomatous meningoencephalomyelitis.
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    ABSTRACT: An aged Maltese dog (dog 1) showed gait ataxia for a month and suddenly died after convulsion. An aged Toy Poodle dog (dog 2) showed sudden blindness with unresponsive pupillary light reflexes and sudden death due to acute cardiac failure. Histological examination of the two dogs demonstrated severe granulomatous perivascular inflammation in the white matter throughout the central nervous system (CNS) including the brain and spinal cord. Based on the clinical and pathological findings, these dogs were diagnosed as granulomatous meningoencephalomyelitis (GME). In dog 2, the inflammatory changes predominated in the visual system such as the optic nerve, optic tract and optic radiation in the cerebrum (ocular form). Distribution pattern of the inflammatory lesions in the CNS was compared between the two dogs.
    Journal of Veterinary Medical Science 05/2009; 71(4):509-12. · 0.85 Impact Factor
  • Article: Urinary trypsin inhibitor protects against liver injury and coagulation pathway dysregulation induced by lipopolysaccharide/D-galactosamine in mice.
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    ABSTRACT: Urinary trypsin inhibitor (UTI), a serine protease inhibitor, has been widely used for patients with inflammatory disorders including disseminated intravascular coagulation, shock, and pancreatitis in Japan. Our recent studies using UTI-null (-/-) mice have shown that UTI protects against systemic inflammatory responses and acute lung injury. However, the role of UTI in liver injury has not been elucidated. This study determined the contribution of UTI to liver injury and coagulatory disturbance induced by lipopolysaccharide and D-galactosamine (LPS/D-GalN) using UTI (-/-) and wild-type (WT) mice. LPS/D-GalN treatment caused severe liver injury characterized by neutrophilic inflammation, hemorrhagic change, necrosis, and apoptosis, which was more prominent in UTI (-/-) than in WT mice. In both genotypes of mice, LPS/D-GalN challenge caused elevations of aspartate amino-transferase and alanine amino-transferase, prolongation of the prothrombin and activated partial thromboplastin time, and decreases in fibrinogen and platelet counts, as compared with vehicle challenge. These changes, however, were significantly greater in UTI (-/-) than in WT mice. Circulatory levels of tumor necrosis factor (TNF)-alpha (P<0.05) and interferon (IFN)-gamma were also greater in UTI (-/-) than in WT mice after LPS/D-GalN challenge. These results suggest that UTI protects against severe liver injury and subsequent coagulatory disturbance induced by LPS/D-GalN, which was mediated, at least partly, through the suppression of TNF-alpha production along with its antiprotease activity.
    Laboratory Investigation 04/2009; 89(7):833-9. · 3.64 Impact Factor
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    Article: Metallothionein as an anti-inflammatory mediator.
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    ABSTRACT: The integration of knowledge concerning the regulation of MT, a highly conserved, low molecular weight, cystein-rich metalloprotein, on its proposed functions is necessary to clarify how MT affects cellular processes. MT expression is induced/enhanced in various tissues by a number of physiological mediators. The cellular accumulation of MT depends on the availability of cellular zinc derived from the diet. MT modulates the binding and exchange/transport of heavy metals such as zinc, cadmium, or copper under physiological conditions and cytoprotection from their toxicities, and the release of gaseous mediators such as hydroxyl radicals or nitric oxide. In addition, MT reportedly affects a number of cellular processes, such as gene expression, apoptosis, proliferation, and differentiation. Given the genetic approach, the apparently healthy status of MT-deficient mice argues against an essential biological role for MT; however, this molecule may be critical in cells/tissues/organs in times of stress, since MT expression is also evoked/enhanced by various stresses. In particular, because metallothionein (MT) is induced by inflammatory stress, its roles in inflammation are implied. Also, MT expression in various organs/tissues can be enhanced by inflammatory stimuli, implicating in inflammatory diseases. In this paper, we review the role of MT of various inflammatory conditions.
    Mediators of Inflammation 02/2009; 2009:101659. · 3.26 Impact Factor
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    Article: Acute and Subacute Pulmonary Effects of Diesel Exhaust Particles in Mice: Pathological Changes and Translocation Pathways to the Circulation
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    ABSTRACT: To study the acute and subacute pulmonary effects of diesel exhaust particles (DEPs), mice were intratracheally instilled with 25, 50 or 100 μg of DEPs for dose response experiments. Histological alterations were determined at 3 days post-exposure. 50 or 100 μg of DEPs produced mild to moderate pulmonary inflammation and tissue injury characterized by infiltration of neutrophils and active alveolar macrophages (AMs), focal alveolitis and particle-laden AMs accumulation. Ultrastructural studies of treated animals showed the dissociation of basement membranes and erosion of type I alveolar epithelial cells. To investigate the time response, mice were instilled with 50 μg of DEPs and sacrificed at intervals from 1 to 30 days post-exposure. DEPs induced pulmonary inflammation and injury at acute period; however, these changes gradually regressed during the experiment. These results suggest that instillation of small doses of DEPs causes transient acute mild to moderate lung inflammation and tissue damage. The evidences of the DEPs distribution in lung tissues were also elucidated throughout the observation time. The main possible translocation pathway of DEPs from the lung to the circulation in this study could be cell mediated active transportation and direct penetration through the area of alveolar interstitial damages.
    Vet. Med. 311 Thai J. Vet. Med. 01/2009; 39(39):311-318.

Institutions

  • 2011
    • Gifu Pharmaceutical University
      Gifu-shi, Gifu-ken, Japan
  • 2004–2011
    • Tottori University
      • • Faculty of Agriculture
      • • Department of Veterinary Pathology
      Tottori, Tottori-ken, Japan
  • 2010
    • Aichi Gakuin University
      Nagoya-shi, Aichi-ken, Japan
  • 2004–2009
    • National Institute for Environmental Studies
      Tsukuba, Ibaraki-ken, Japan
  • 2006
    • Kyoto Prefectural University of Medicine
      Kyoto, Kyoto-fu, Japan
  • 2002–2005
    • St. Marianna University School of Medicine
      • • Department of Biochemistry
      • • Department of Chemistry
      Kawasaki, Kanagawa-ken, Japan