Simultaneous modeling of microbaroms and microseisms

第6回極域科学シンポジウム[OG] 地圏11月16日（月）　国立極地研究所３階セミナー

Biological Role of Dystroglycan in Schwann Cell Function and Its Implications in Peripheral Nervous System Diseases

Dystroglycan is a central component of the dystrophin-glycoprotein complex (DGC) that links extracellular matrix with cytoskeleton, expressed in a variety of fetal and adult tissues. Dystroglycan plays diverse roles in development and homeostasis including basement membrane formation, epithelial morphogenesis, membrane stability, cell polarization, and cell migration. In this paper, we will focus on biological role of dystroglycan in Schwann cell function, especially myelination. First, we review the molecular architecture of DGC in Schwann cell abaxonal membrane. Then, we will review the loss-of-function studies using targeted mutagenesis, which have revealed biological functions of each component of DGC in Schwann cells. Based on these findings, roles of dystroglycan in Schwann cell function, in myelination in particular, and its implications in diseases will be discussed in detail. Finally, in view of the fact that understanding the role of dystroglycan in Schwann cells is just beginning, future perspectives will be discussed

Dihydroxylation of Naphthalene by Molecular Oxygen and Water Using TiO2 Photocatalysts

TiO2-catalyzed photo-reaction of naphthalene was investigated in mixed solutions of acetonitrile and water. The main products were confirmed to be 1,8- and 1,3-dihydroxynaphthalene, without any 1- or 2-naphthol being detected. Both O2 and H2O were essential to yield the products. The quantum efficiency of the 1,8- and 1,3-dihydroxynaphthalene products reached about 10% at 365 nm after irradiated for 1 h

Chromosomal integration of blaCTX-M genes in diverse Escherichia coli isolates recovered from river water in Japan

Occurrence of extended-spectrum β-lactamase (ESBL)-producing Escherichia coli (ESBLEC) in environmental waters is of great concern. However, unlike clinical ESBLEC, their genetic characteristics, in particular the genetic contexts of ESBL genes, are not well understood. In this study, we sequenced and analyzed the genomes of CTX-M-producing E. coli isolates recovered from river water to fully characterize the genetic contexts of blaCTX-M genes. Among the 14 isolates with completed genomes, blaCTX-M genes were detected on the chromosome in nine isolates. All but one chromosomal blaCTX-M genes were associated with ISEcp1 and were carried on different transposition units ranging in size from 2, 855 bp to 11, 093 bp; the exception, blaCTX-M-2, was associated with ISCR1. The remaining five isolates carried blaCTX-M genes on epidemic IncI1 plasmids of different sequence types (STs) (ST3, ST16, ST113, and ST167) (n = 4) or on an IncB/O/K/Z plasmid (n = 1). This study revealed that environmental E. coli carry blaCTX-M genes in diverse genetic contexts. Apparent high prevalence of chromosomal blaCTX-M potentially indicates that some E. coli can stably maintain blaCTX-M genes in environmental waters, though further studies are needed to confirm this

An azoospermic factor gene, Ddx3y and its paralog, Ddx3x are dispensable in germ cells for male fertility

Takafumi MATSUMURA, Tsutomu ENDO, Ayako ISOTANI, Masaki OGAWA, Masahito IKAWA, An azoospermic factor gene, Ddx3y and its paralog, Ddx3x are dispensable in germ cells for male fertility, Journal of Reproduction and Development, 2019, Volume 65, Issue 2, Pages 121-128, Released April 12, 2019, [Advance publication] Released January 07, 2019, Online ISSN 1348-4400, Print ISSN 0916-8818, https://doi.org/10.1262/jrd.2018-145, https://www.jstage.jst.go.jp/article/jrd/65/2/65_2018-145/_article/-char/e

Ovarian clear cell carcinoma meets metabolism; HNF-1β confers survival benefits through the Warburg effect and ROS reduction.

Ovarian clear cell carcinoma (OCCC) constitutes one of the subtypes of ovarian cancers, but it has unique clinical, histological and biological characteristics, one of which is chemo-resistance. It is also known to develop from endometriotic cyst, a benign ovarian tumor, at relatively high frequency. Recently, it is becoming well known that most of OCCCs express HNF1β, a transcription factor, which is closely associated with the development of liver, pancreas and kidney, as well as occurrence of familial forms of type 2 diabetes. Expression of HNF1β is now regarded as a hallmark of this tumor. Nevertheless, exact biological function of this gene in OCCC has not been clarified. We have shown in previous studies that microenvironment in endometriotic cysts contains severe oxidative stress and OCCC develops under such stressful environment as stress-resistant tumor, which may lead to chemo-resistance. We also showed that increased expression of HNF1β facilitates glucose uptake and glycolysis, which is known as Warburg effect. In the previous issue of this journal, by using comprehensive metabolome analysis, we report that HNF1β actually reduces and protects themselves from internal oxidative stress by dramatically changing cellular metabolism. In this article, we review the relevance and significance of cancer-specific metabolism and how they are associated with biological characteristics of OCCC via expression of HNF1β, along with future clinical implications of targeting cancer-specific metabolism

Time-Dependent Changes in Risk of Progression During Use of Bevacizumab for Ovarian Cancer

卵巣がんに対する分子標的薬「ベバシズマブ」の効果を解析 投与終了後に悪化リスクが高まることを確認、最適な投与法を提案. 京都大学プレスリリース. 2023-08-03.[Importance] Although bevacizumab has been used in the treatment of ovarian cancer, its optimal use is unknown. [Objective] To investigate time-dependent changes in the outcomes of bevacizumab therapy. [Design, Setting, and Participants] This cohort study was conducted using published data from 7 previous randomized phase 3 clinical trials with bevacizumab (ICON7, GOG-0218, BOOST, GOG-0213, OCEANS, AURERIA, and MITO16B) from January 10 to January 31, 2023. From 2 ancillary analyses of the ICON7 trial with individual patient data and tumor gene expression profiles, an ICON7-A cohort was generated comprising 745 cases. From other studies, published Kaplan-Meier curves were graphically analyzed. [Exposures] Bevacizumab treatment vs placebo or no treatment. [Main Outcomes and Measures] Restricted mean survival time and relative risk of progression at a given time point between bevacizumab treatment and control groups. [Results] In the ICON7-A cohort (n = 745), restricted mean survival analysis showed that bevacizumab treatment (n = 384) had significantly better progression-free survival (PFS) than the control (n = 361) before bevacizumab discontinuation (restricted mean survival time ratio, 1.08; 95% CI, 1.05-1.11; P < .001), but had significantly worse PFS after bevacizumab discontinuation (0.79; 95% CI, 0.69-0.90; P < .001), showing rebound. In a post hoc analysis, the rebound was similarly observed both in homologous recombination deficiency (HRD) (before, 1.05; 95% CI, 1.02-1.09; P < .001; after, 0.79; 95% CI, 0.63-0.98; P = .04) and non-HRD tumors (before, 1.08; 95% CI, 1.03-1.15; P < .001; after, 0.71; 95% CI, 0.56-0.90; P < .001) of the serous subtype, but not in the nonserous subtype (before, 1.11; 95% CI, 1.05-1.18; P < .001; after, 0.94; 95% CI, 0.78-1.15; P = .57). In Kaplan-Meier curve image–based analysis, the trend of rebound effect was consistently observed in the overall ICON7 and GOG-0218 cohorts and their subgroups stratified by prognostic factors, homologous recombination–associated mutations, and chemotherapy sensitivity. In contrast, no such trend was observed in the studies GOG-0213, OCEANS, AURERIA, and MITO16B, in which patients who experienced relapse received bevacizumab until progression. [Conclusions and Relevance] In ovarian cancer, bevacizumab may reduce progression for approximately 1 year after initiation, but discontinuation may increase subsequent progression in the serous subtype regardless of HRD status. The results suggest that in the first-line treatment, bevacizumab may be more beneficial in patients with a shorter prognosis who are less likely to experience the rebound outcome