HSP70 and c-Fos expression of brain stem hypoglossal nucleus in drowning

The brain stem hypoglossal nucleus (HN) is the center of nerves innervating the upper respiratory tract and is related to control of mastication, deglutition, speech and respiration. To elucidate the relationship between asphyxia and the HN, we investigated the change of hypoglossal neurons in cases of hanging, strangulation, smothering, choking, drowning and respiratory failure. Using immunohistochemical techniques, we observed the brain stem HN with antibodies against microtubule-associated protein2(MAP2), muscarinic acetylcholine receptor (mAChR), c-fos gene product (c-Fos) and 72kD heat-shock protein (HSP70). MAP2, a cytoskeletal protein of the neuron, is a marker of neuronal damage. Muscarinic AChR was used as a marker of neuronal membrane and ACh signaling. We employed both HSP70 and c-Fos as markers of stress- or damage-related events. We measured the percentage of immunopositive neurons in total neurons of HN. Drowning produced higher expression of HSP70 and c-Fos than other causes of asphyxia, suggesting that drowning induces more severe damage in HN neurons. Furthermore, it was suspected that neuronal changes in drowning might relate to functions of the HN. These observations indicate that immunohistochemical examination of the brain stem HN could provide useful information for determining the cause of asphyxia

Structure of Musashi1 in a complex with target RNA: the role of aromatic stacking interactions

Mammalian Musashi1 (Msi1) is an RNA-binding protein that regulates the translation of target mRNAs, and participates in the maintenance of cell ‘stemness’ and tumorigenesis. Msi1 reportedly binds to the 3′-untranslated region of mRNA of Numb, which encodes Notch inhibitor, and impedes initiation of its translation by competing with eIF4G for PABP binding, resulting in triggering of Notch signaling. Here, the mechanism by which Msi1 recognizes the target RNA sequence using its Ribonucleoprotein (RNP)-type RNA-binding domains (RBDs), RBD1 and RBD2 has been revealed on identification of the minimal binding RNA for each RBD and determination of the three-dimensional structure of the RBD1:RNA complex. Unique interactions were found for the recognition of the target sequence by Msi1 RBD1: adenine is sandwiched by two phenylalanines and guanine is stacked on the tryptophan in the loop between β1 and α1. The minimal recognition sequences that we have defined for Msi1 RBD1 and RBD2 have actually been found in many Msi1 target mRNAs reported to date. The present study provides molecular clues for understanding the biology involving Musashi family proteins

ガクセイ アンケート チョウサ ニヨル コウギ ヒョウカ ト ソノ モンダイテン

近年,医学教育改革が目まぐるしく行われている.その中で,学生による講義評価が行われはじめているが,まだその報告は少ない.獨協医科大学では学年委員会が主体となって,講義・実習に対するアンケート調査を第1学年から第4学年まで行った.その結果,講義に対して「十分に満足している」という学生は,どの学年においても多くはなかった.さらに,「わかりやすい講義」をしている教員の共通点は,板書・プリント・シラパスを活用しているという点であった.実習に関しては,「基礎医学」に関わる実習に対しての評価が高かった.今後の医学教育において,学生の意見の反映がよりよい講義につながるものと考えられる.Extensive innovations in medical education have been carried out in recent years in our country. Although student evaluations of lectures have been conducted, there have been few reports on this issue. Thus, our committee consisting of representatives of every grade played a leading role in making and evaluating a questionnaire investigation of the lectures and the experiments. The investigation covered students from freshmen to seniors. We found that there were few students in each grade who were satisfied with the lectures. Students gave high marks to lecturers who wrote in detail on the blackboard, distributed well-organized documents, and made practical use of the syllabus. Experiments concerning the preclinical course were also well accepted. We consider that this sort of investigation will be influential in improving the quality of lectures

A multiplex PCR-based molecular identification of five morphologically related, medically important subgenus stegomyia mosquitoes from the genus Aedes (Diptera: Culicidae) found in the Ryukyu Archipelago, Japan

Internal transcribed spacer regions of ribosomal DNA were sequenced, and new species-specific primers were designed to simplify the molecular identification of five morphologically related subgenus Stegomyia mosquito species-Aedes aegypti, Ae. albopictus, Ae. riversi, Ae. flavopictus, and Ae. daitensis-found in the Ryukyu Archipelago, Japan. Each newly designed primer was able to amplify a species-specific fragment with a different size. Conditions for multiplex PCR were optimized to identify all five species in a single PCR. This method is a convenient tool for entomological field surveys, particularly in arbovirus endemic/epidemic areas where some of these species coexist