Experimental Pulmonary Granuloma Mimicking Sarcoidosis Induced by Propionibacterium acnes in Mice

Propionibacterium acnes has been implicated as an etiologic agent of sarcoidosis since the isolation of this bacterium from sarcoid lesions. We experimentally produced a murine pulmonary granuloma model using P. acnes with several features that simulate sarcoidosis. Mice were sensitized with heat-killed P. acnes and complete Freund's adjuvant and were subsequently challenged with heat-killed P. acnes at 2-week intervals. P. acnes-challenged mice developed epitheloid cell granulomas in the lungs. These mice showed a pulmonary immune response characterized by an increased number of T-lymphocytes, especially CD4 cells, and the ratio of CD4/CD8 in bronchoalveolar lavage (BAL) fluid also increased. Furthermore, significant elevations in both angiotensin-converting enzyme (ACE) serum levels and antibody titers against P. acnes were observed. Mice sensitized with P. acnes without complete Freund's adjuvant were capable of forming pulmonary granulomas, which appeared to be caused by indigenous P. acnes. The genome of P. acnes was found in the lungs, BAL cells, hilar lymph nodes, liver, and spleen in non-sensitized mice, which were thought to be germ-free. These results suggest that the immune response against indigenous P. acnes may play an important role in the pathogenesis of granuloma formation in a murine model.</p

Mixed Type of Malignant Mesothelioma in an Aged Male ICR Mouse

Multiple whitish nodules in the thoracic cavity at the site of the thymus were observed in a 101-week-old male ICR mouse. In a histopathological examination, the neoplastic cells were predominantly fusiform in shape and proliferated in sarcomatoid growth patterns. Some neoplastic cells showed epithelial growth patterns, such as the ductal structures. Mitotic figures were frequently seen, and small necrotic foci and invasion to adjacent thoracic organs were noted. In Alcian blue staining, bluish materials were observed between fusiform-shaped cells and in some of the lumens of the ductal structures. In immunohistochemistry, both fusiform-shaped and ductal structure-forming cells were positive for vimentin and weakly positive to positive for cytokeratin. Based on the aforementioned findings, the thoracic nodules were diagnosed as a mixed type of malignant mesothelioma. This case was thought to be rare because of the very low occurrence of spontaneous mesothelioma in mice

Effects of high magnetic field on Euglena gracilis

The effects of high magnetic field on Euglena gracilis Z were examined. When a horizontal magnetic field gradient (ca. 400 T2m-1) was applied, living E. gracilis moved to a higher field (positive magnetotaxis), whereas dead one gathered in a lower field. Magnetotaxis was not observed in a uniform magnetic field of 8 T. E. gracilis was oriented almost perpendicularly to the magnetic field regardless of life and death. Magnetotaxis of E. gracilis would be explained by taking into account inhomogeneous magnetic forces on and magnetic orientation of E. gracilis

Lavender Essential Oil and Its Main Constituents Inhibit the Expression of TNF-α-induced Cell Adhesion Molecules in Endothelial Cells

Lavender essential oil (Lvn) has anti-inflammatory effects in an ovalbumin-sensitized murine model of asthma, and inhibits inflammatory cell infiltration into the lungs. The anti-inflammatory effects of Lvn on cell adhesion molecules are not clear. Here we evaluated the effects of Lvn and its main constituents, linalyl acetate (LA) and linalool (LO), on the expression of tumor necrosis factor-alpha (TNF-α)-induced cell adhesion molecules in murine brain endothelial bEnd.3 cells and human umbilical vein endothelial cells (HUVECs). The bEnd.3 cells were treated with Lvn, LA, or LO and subsequently stimulated with TNF-α. The mRNA expression levels of cell adhesion molecules were detected using RT-PCR. E-selectin and P-selectin protein and phosphorylated-NF-κB p65 were detected by western blotting. The effects of Lvn on HUVECs were measured by RT-PCR. In bEnd.3 cells, Lvn and LA suppressed TNF-α-induced E-selectin, P-selectin, vascular cell adhesion molecule-1, intercellular adhesion molecule-1, and phosphorylated-NF-κB p65 in the nucleus; LO did not suppress P-selectin or phosphorylated-NF-κB p65. Lvn inhibited TNF-α-induced E-selectin mRNA in HUVECs. These results indicate that Lvn and LA inhibit TNF-α-induced cell adhesion molecules in endothelial cells through the suppression of NF-κB activation. Consequently, Lvn or other essential oils including LA may be useful as alternative anti-inflammatory medicines

Ethylene Glycol Monomethyl Ether–Induced Toxicity Is Mediated through the Inhibition of Flavoprotein Dehydrogenase Enzyme Family

Ethylene glycol monomethyl ether (EGME) is a widely used industrial solvent known to cause adverse effects to human and other mammals. Organs with high metabolism and rapid cell division, such as testes, are especially sensitive to its actions. In order to gain mechanistic understanding of EGME-induced toxicity, an untargeted metabolomic analysis was performed in rats. Male rats were administrated with EGME at 30 and 100 mg/kg/day. At days 1, 4, and 14, serum, urine, liver, and testes were collected for analysis. Testicular injury was observed at day 14 of the 100 mg/kg/day group only. Nearly 1900 metabolites across the four matrices were profiled using liquid chromatography-mass spectrometry/mass spectrometry and gas chromatography-mass spectrometry. Statistical analysis indicated that the most significant metabolic perturbations initiated from the early time points by EGME were the inhibition of choline oxidation, branched-chain amino acid catabolism, and fatty acid β-oxidation pathways, leading to the accumulation of sarcosine, dimethylglycine, and various carnitine- and glycine-conjugated metabolites. Pathway mapping of these altered metabolites revealed that all the disrupted steps were catalyzed by enzymes in the primary flavoprotein dehydrogenase family, suggesting that inhibition of flavoprotein dehydrogenase–catalyzed reactions may represent the mode of action for EGME-induced toxicity. Similar urinary and serum metabolite signatures are known to be the hallmarks of multiple acyl-coenzyme A dehydrogenase deficiency in humans, a genetic disorder because of defects in primary flavoprotein dehydrogenase reactions. We postulate that disruption of key biochemical pathways utilizing flavoprotein dehydrogenases in conjugation with downstream metabolic perturbations collectively result in the EGME-induced tissue damage

An Enforcement of 'Distinct Teaching Practice' at Hiroshima University (III)

本稿の目的は, 一昨年度より本格的に実施された「特色ある教育実習プログラム」の実施に関して, 「教育実習指導A」及び「教育実習指導B」の効果に焦点化して報告することである。検討の結果以下の点が明らかとなった。①「教育実習指導A」は「小学校教育実習Ⅰ」に向け, 実習に対する意欲の喚起, さらに課題意識の明確化に有効であったといえる。しかし, 授業観察の観点, 時間割作成等に関する改善点・要望の記述が多くみられた。今後はこれらに対する支援の充実が課題である。②「教育実習指導B」は, 「教育実習の理解度」「教育実習に参加した印象」「本実習までの課題」に関して概ね目的の達成が見られたといえる。課題としては, やはり3日間という短期間であるためか, 教科指導の観察が中心となり, 学級経営などの理解が十分でないことを挙げることができる。③「特色ある教育実習プログラム」全体の中での「教育実習指導A」及び「教育実習指導B」の目的の明確化と, 1年次生から3年次生まで配置されている各種教育実習との整合性が課題として指摘された。広島大学教育学部・各附属学校で育成すべき教師像を明確化し, 再度教育実習システム全体を再構築することが必要とされた