加藤 好光

Huntingtin-associated protein 1 (HAP1) is abundantly expressed in the neurons of the central nervous system and forms unique intracytoplasmic inclusions of unknown function called 'stigmoid bodies' (STBs). Transmission electron microscopy has revealed that the STBs are aggregates of granules containing cavities with a diameter of 0.5-3 µm. Small STBs fuse to form larger STBs, the size of which is said to vary depending on the developmental growth stage and brain region. Light microscopy can only reveal that these STBs have similar circular shapes due to its limited resolution. Therefore, light microscopy is only fit for the study of the STB distribution and quantitative changes. We, herein, suggest the adoption of correlative light and electron microscopy, which combines confocal laser scanning microscopy and scanning electron microscopy as the method allowing us to identify the huntingtin-associated protein 1-positive STBs in formalin-fixed paraffin-embedded (FFPE) sections. This approach allows us to study the three-dimensional morphology of immunolabeled objects in histopathological specimens. The STBs in FFPE sections of murine hypothalami reflected the transmission electron microscopic images of Epon-embedded STBs, although we were not able to observe any organelle covering the STBs of the FFPE sections. Furthermore, we were able to reconstruct the three-dimensional structure of the STB, and we identified it to be of spherical form, covered with mitochondria and rough endoplasmic reticulum, and bearing a cluster of cavities in the centre. In the future, we might gain new insights by comparing the three-dimensional structure of the STB between different neurons and under a variety of conditions.

光学顕微鏡レベルで鍍銀陽性小体(核小体様封入体)を観察するためにグルタールアルデヒド含有固定が必須であるかどうか検討した。正常ddY雄マウスを使用し、10%ホルマリン灌流固定群、2.5%グルタールアルデヒド+5%ホルマリン混合液固定群、グルタールアルデヒド0.1%、0.5%、1.0%、2.5%灌流固定群を設定した。2.5%グルタールアルデヒドと5%ホルマリン混合液固定液で1日固定した標本では鍍銀陽性小体の存在が確認できた。最初に10%ホルマリンで固定された脳組織でも、その後にグルタールアルデヒド含有固定液で再固定すれば、鍍銀陽性小体の検索が可能であることが確認された。パラフィン切片での鍍銀陽性小体である核小体様封入体の染色にはグルタール含有固定が必須であることが証明され、最適な固定液は2.5%グルタールアルデヒドと5%ホルマリンの混合液であった。

本学では、臨床検査技師教育課程において人体解剖実習を導入し、その有効かつ有益な教育方法を考察した。その結果、「心臓の構造を理解できた」と回答した学生は96%であり、他臓器においても80%以上と高率であった。また、医療職として必須の倫理的教育効果についても「ご遺体の尊厳についての理解」に関して96%の学生から肯定的な回答が得られた。一方で、教員の不足等による不満もあったが、今後は大学院生や勉学の意識の強い卒業生の実習参加などを通して、より広くかつ意義深い実習にしていきたいと考えている。(著者抄録)

Although it has been suggested that the combination of exercise and bryostatin-1 administration may induce greater functional recovery than exercise alone, the detailed molecular mechanisms are not well known. Here, we examined the relationship between this combination treatment and monoamine dynamics in the cerebral cortex peri-infarction area to promote our understanding of these molecular mechanisms. Experimental cerebral cortex infarctions were produced by photothrombosis in rats. Voluntary exercise was initiated 2 days after surgery. Motor performance was then measured using the rotarod test. Monoamine concentrations in the perilesional cortex were analyzed by high-performance liquid chromatography. In behavioral evaluations, performance in the rotarod test was significantly increased by exercise. Moreover, performance in the rotarod test after the combination of exercise and bryostatin-1 administration was significantly greater than that after exercise alone. In the analysis of monoamines, serotonin (5-HT) concentrations were significantly higher in the groups treated with exercise and bryostatin-1. In addition, 5-HT turnover was significantly lower in the groups treated with exercise and bryostatin-1. Furthermore, the mean latency in the rotarod test showed a significant positive correlation with 5-HT levels. In immunohistochemical analysis, 5-HT immunoreactivity in the dorsal raphe nucleus was shown to be higher in the groups treated with exercise. In the present study, we detected changes in the levels of monoamines associated with the combined treatment of exercise and bryostatin-1 administration in the perilesional cortex. It has been suggested that this combination of therapies may affect 5-HT turnover and serve to increase local 5-HT concentrations in the perilesional area. Copyright (C) 2016 Wolters Kluwer Health, Inc. All rights reserved.

Helicobacter pylori (H. pylori) is a very important pathogenic bacteria associated with many upper gastrointestinal diseases including chronic active gastritis, chronic inactive gastritis, gastric and duodenal peptic ulcer disease, gastric MALT lymphoma, and gastric adenocarcinoma. There are no distinct endoscopic patterns of chronic H. pylori gastritis. The diagnosis of H. pylori gastritis is made by pathologic examination of gastric mucosal biopsies or by the detection of urease in mucosal specimens using the CLO test or urea breath test.  H. pylori infection has been diagnosed based on the histological laboratory procedure and indirectly from a background gastric-mucous-membrane view. Alcian Yellow Touidine Blue staining is available and useful as one of the diagnostic methods.

Recently, it has become widely known that rehabilitative training after stroke brings about some improvement of paralysis and disability; however, not much is known about the relationship between paralysis recovery and the participation of plasticity-related molecules. Hence, the localization and level of expression of several proteins in the cerebral cortex of rat groups with/without voluntary exercise using a running wheel after photo thrombotic infarction were examined in this study. In behavioral evaluation, the mean latency until falling from a rotating rod in the group with voluntary exercise at 6 days after infarction was significantly longer than that in the group without exercise. Immunohistochemical localization of c-Fos protein after behavioral test occurred in the area surrounding the infarction core in the exercise group. In protein expression analysis, protein kinase C (PKC), growth-associated protein 43 (GAP43) and phosphorylated at serine 41 GAP43 (p-GAP43) were significantly increased after voluntary exercise compared with those in rats without exercise. Expression of PKC immunoreactivity was observed in layer III of the perilesional cortex in rats with exercise, and the intracellular localization in the pyramidal neurons was mainly translocated to the plasma membrane. The expression and localization of these proteins may be related to the underlying mechanisms of exercise-induced paralysis recovery, that is, neuronal plasticity and remodeling of cortical connections through the phosphorylation of GAP43 by interaction with PKC. In the present study, the participation of at least some of the modulators associated with the improvement of motor deficit adjacent to the brain lesion might have been detected.