Preparation of α-mannoside hydrogel and electrical detection of saccharide-protein interactions using the smart gel-modified gate field effect transistor

The purpose of this study was to detect saccharide-protein interaction capitalizing on the gel-modified field effect transistor [FET]. A lectin-sensitive polymer gel that undergoes volume changes in response to the formation of molecular complex between 'pendant' carbohydrate and a 'target' lectin concanavalin A [Con A] was synthesized. It was revealed that direction and magnitude of the gel response (swelling or deswelling) could be readily designed depending on composition and network density of the gel. The Con A-sensitive polymer gel has shown the ability to transduce the detection of saccharide-protein interactions into electrical signals for FET

A Fatal Aortoesophageal Fistula Caused by Critical Combination of Double Aortic Arch and Nasogastric Tube Insertion for Superior Mesenteric Artery Syndrome

Double aortic arch (DAA) is a rare vascular congenital abnormality. Since a vascular ring surrounds bronchus and esophagus, any oral or nasal intubation can physically cause fatal aortoesophageal fistula (AEF). We report herein the first case of association of DAA and superior mesenteric artery (SMA) syndrome and the second case of AEF caused by nasogastric intubation in an adult with DAA. A 19-year-old woman visited our hospital for nausea and vomiting. She was diagnosed with SMA syndrome by computed tomography (CT). Nasogastric intubation relieved her symptoms in 4 days. Extramural compression with top ulceration was found in esophagogastroduodenoscopy on the 5th hospital day. She suddenly showed massive hematemesis on the 12th hospital day. AEF was found by CT. Soon, she died despite of intensive care. Retrospective interview disclosed the fact that DAA was pointed out in her childhood. We conclude that intubation must be avoided in DAA and a detailed clinical interview about DAA is mandatory to avoid AEF

Epigenetic Regulation of Intronic Transgenes in Arabidopsis

Defense mechanisms of plant genomes can epigenetically inactivate repetitive sequences and exogenous transgenes. Loss of mutant phenotypes in intronic T-DNA insertion lines by interaction with another T-DNA locus, termed T-DNA suppression, has been observed in Arabidopsis thaliana, although the molecular basis of establishment and maintenance of T-DNA suppression is poorly understood. Here we show that maintenance of T-DNA suppression requires heterochromatinisation of T-DNA sequences and the nuclear proteins, INCREASED IN BONSAI METHYLATION 2 (IBM2) and ENHANCED DOWNY MILDEW 2 (EDM2), which prevent ectopic 3′ end processing of mRNA in atypically long introns containing T-DNA sequences. Initiation of T-DNA suppression is mediated by the canonical RdDM pathway after hybridisation of two T-DNA strains, accompanied by DNA hypermethylation of T-DNA sequences in the F1 generation. Our results reveal the presence of a genome surveillance mechanism through genome hybridisation that masks repetitive DNAs intruding into transcription units

Comparative genomics of Glandirana rugosa using unsupervised AI reveals a high CG frequency

The Japanese wrinkled frog (Glandirana rugosa) is unique in having both XX-XY and ZZ-ZW types of sex chromosomes within the species. The genome sequencing and comparative genomics with other frogs should be important to understand mechanisms of turnover of sex chromosomes within one species or during a short period. In this study, we analyzed the newly sequenced genome of G. rugosa using a batch-learning self-organizing map which is unsupervised artificial intelligence for oligonucleotide compositions. To clarify genome characteristics of G. rugosa, we compared its short oligonucleotide compositions in all 1-Mb genomic fragments with those of other six frog species (Pyxicephalus adspersus, Rhinella marina, Spea multiplicata, Leptobrachium leishanense, Xenopus laevis, and Xenopus tropicalis). In G. rugosa, we found an Mb-level large size of repeat sequences having a high identity with the W chromosome of the African bullfrog (P. adspersus). Our study concluded that G. rugosa has unique genome characteristics with a high CG frequency, and its genome is assumed to heterochromatinize a large size of genome via methylataion of CG

Epigenetic regulation of spurious transcription initiation in Arabidopsis

In plants, epigenetic regulation is critical for silencing transposons and maintaining proper gene expression. However, its impact on the genome-wide transcription initiation landscape remains elusive. By conducting a genome-wide analysis of transcription start sites (TSSs) using cap analysis of gene expression (CAGE) sequencing, we show that thousands of TSSs are exclusively activated in various epigenetic mutants of Arabidopsis thaliana and referred to as cryptic TSSs. Many have not been identified in previous studies, of which up to 65% are contributed by transposons. They possess similar genetic features to regular TSSs and their activation is strongly associated with the ectopic recruitment of RNAPII machinery. The activation of cryptic TSSs significantly alters transcription of nearby TSSs, including those of genes important for development and stress responses. Our study, therefore, sheds light on the role of epigenetic regulation in maintaining proper gene functions in plants by suppressing transcription from cryptic TSSs

日本とその近隣諸国で分離されたShigella sonneiのコリシン型,生化学型および薬剤耐性パターン

A modification of Abbott and Shannon\u27s colicin typing method for Shigella sonnei which was established recently as a standard method in Japan was described. This method increases by three or four indicators of E. coli K-12 mutant origin, and it is not only to make a clear distinction between either types 6 and 11 or types 4 and 14, but also to establish three new colicin types 4A, 9A and 13A. Typing results of 1,148 strains representing "foci" which were isolated in Japan especially in the western part, were presented. In Japan at present, type 14 is at the top of epidemic strains, type 6 ranks next, and types O, 8, 13A, 4, 2, etc. follow in order, among them only types 8 and 13A show some difference in interregional distribution. Besides, 39 strains isolated in the neighboring countries of Japan were used for typing. There was a most distinct difference in colicin type between here and there. The strains examined biochemically were determined by 78 percent as type RM of Gillies (xylose negative, raffinose and melibiose positive), and by 96 percent as type "a" of Szturm-Rubinsten (ONPG positive, rhamnose and xylose negative). Both the biochemical types were equally distributed among colicin types other than type 12; in colicin type 12, strains showing various fermentation patterns were found. The resistance of the strains to sulfa-drug and three antibiotics raised gradually since 1963 and thereabout, and it was at its maximum in 1967 irrespective of colicin type. Only strains of colicin type 14, which appeared for the first time in 1963 showed the maximum from the beginning. In the transition stage of resistance acquisition, it was possible to use resistance pattern as a subsidiary epidemiological marker in combination with colicin type provided that epidemics had been caused by colicin types 6, O, 8, etc. Two examples of application of this combination use were presented; the first case deals with epidemiological analysis of a mass outbreak, and the second with epidemiological connection among many epidemics in a district within a definite period of time.日本で改良され,標準法として一般に実施されているAbbott-ShannonのShigella sonneiコリシン型別法(いわゆる型別部会法)を紹介した.本法は大腸菌K-12変異菌から誘導した抵抗変異株3ないし4株を原法指示菌に追加したもので,原法では区別が困難であった6型と11型,および4型と14型を明瞭に分け,また新コリシン型3種,4A,9A,13Aを追加したものである.主として西日本で分離された,ホーカスを代表する1,148株のS. sonneiが本法による型別に供された.現在の日本では14型が首位,6型これに次ぎ,O型,8型,13A,4≦,2型などがこの順に検出され,うち8型と13Aは国内的に地理的分布上のかなりの差異を示した.ほかに近隣諸国分離の39株を型別したが,その成績は日本のそれと大いに差異があった.生化学的型別の結果は,78%までがGilliesのRM型(キシローゼ陰性,ラフィノーゼ,メリビオーゼ陽性),96%までがSzturm-Rubinstenのa型(ONPG陽性,ラムノーゼ,キシローゼ陰性)であった.この両型はともに12型以外の各コリシン型に平均的に分布し,12型においてのみ各種の糖分解型式を示すものが見出された.これらの菌株のサルファ剤と3種の抗生物質に対する抵抗性は1963年頃から次第に高まり,1967年に至ってコリシン型に関係なくすべてが最高の抵抗を示した.ただし14型だけはそれが最初に現われた1963年には,4剤に対して既に最高の抵抗を示していた.この耐性獲得の途上にある時期では,6型,O型,8型などによる流行の場合に限って,薬剤耐性パターンをコリシン型と組合せて一つの補助的な疫学的マーカーとして利用することが可能であった.この組合せ使用の二つの応用例を記述したが,一つはある集団発生の疫学的分析に関するものであり,もう一つは,ある地方ある期間内における各流行例間の関連に関するものであった