SIV replication in human cells

Current human immunodeficiency virus type 1 pandemic is believed to originate from cross-species transmission of simian immunodeficiency virus (SIV) into human population. Such cross-species transmission, however, is not efficient in general, because viral replication is modulated by host cell factors, with the species-specificity of these factors affecting viral tropism. An understanding of those host cell factors that affect viral replication contributes to elucidation of the mechanism for determination of viral tropism. This review will focus an anti-viral effect of ApoB mRNA editing catalytic subunit, tripartite motif protein 5 alpha, and cyclophilins on SIV replication and provide insight into the mechanism of species-specific barriers against viral infection in human cells. It will then present our current understanding of the mechanism that may explain zoonotic transmission of retroviruses

Microtechnologies for membrane protein studies

Despite the rapid and enormous progress in biotechnologies, the biochemical analysis of membrane proteins is still a difficult task. The presence of the large hydrophobic region buried in the lipid bilayer membrane (transmembrane domain) makes it difficult to analyze membrane proteins in standard assays developed for water-soluble proteins. To handle membrane proteins, the lipid bilayer membrane may be used as a platform to sustain their functionalities. Relatively slow progress in developing micro total analysis systems (μTAS) for membrane protein analysis directly reflects the difficulty of handling lipid membranes, which is a common problem in bulk measurement technologies. Nonetheless, researchers are continuing to develop efficient and sensitive analytical microsystems for the study of membrane proteins. Here, we review the latest developments, which enable detection of events caused by membrane proteins, such as ion channel current, membrane transport, and receptor/ligand interaction, by utilizing microfabricated structures. High-throughput and highly sensitive detection systems for membrane proteins are now becoming a realistic goal. Although most of these systems are still in the early stages of development, we believe this field will become one of the most important applications of μTAS for pharmaceutical and clinical screenings as well as for basic biochemical research

The Greatness of the Seminar as a Community Created by Prof. Mimura

三村真弓教授退職記念号 Special Number Commemorating the Retirement of Professor Mayumi Mimur

Factors Affecting Postoperative Hearing Results in Type IV Tympanoplasty: Preliminary Study of the Influence of External Auditory Canal Packing Material

[Background] Postoperative hearing results of type IV tympanoplasty have been shown to have poorer results than other reconstruction techniques. There are numerous reports evaluating the factors for hearing improvement. This preliminary study aimed to analyze and determine the factors that affect hearing results. [Methods] A total of 80 patients who underwent type IV tympanoplasty were evaluated to participate in this study. The medical records of the candidate patients were collected retrospectively. Fifty out of the 80 recruited patients were excluded due to the following reasons: they could not be followed-up for more than a year after the final operation, their initial surgery was not performed in our department, or they needed a revision surgery. The pre-, intra-, and postoperative factors were evaluated and analyzed using EZR software. Cases were divided into two groups according to postoperative hearing results, and each factor was analyzed univariately. The explanatory variables included in the multivariate analysis were the variables that satisfied P < 0.1 in the univariate analysis. Furthermore, all cases were divided into two groups according to the qualitative variables that showed significant difference in the multivariate analysis, and the background factors were evaluated. [Results] The results of univariate analysis showed P < 0.1 for ‘Age’ and ‘Material of external auditory canal (EAC) packing’. Multivariate analysis showed P < 0.05 for both. The comparison between the two packing material groups showed that the gauze group was more likely to have improved hearing than Spongel? group, and the ossicular chain condition of the gauze group was maintained better. [Conclusion] ‘Age’ and ‘Material of EAC packing’ were considered to be significant factors affecting the postoperative hearing results. The selection and use of packing materials that provide stability should be considered to obtain better postoperative hearing results in type IV tympanoplasty