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771.
Kentaro Tominaga Atsunori Tsuchiya Takeshi Mizusawa Asami Matsumoto Ayaka Minemura Kentaro Oka Motomichi Takahashi Tomoaki Yosida Yuzo Kawata Kazuya Takahashi Hiroki Sato Satoshi Ikarashi Kazunao Hayashi Ken-ichi Mizuno Yosuke Tajima Masato Nakano Yoshifumi Shimada Hitoshi Kameyama Shuji Terai 《Biochemistry and Biophysics Reports》2021
It is reported that an increase in aerobic bacteria, a lack of short-chain fatty acids (SCFAs), and immune disorders in the diverted colon are major causes of diversion colitis. However, the precise pathogenesis of this condition remains unclear. The aim of the present study was to examine the microbiota, intestinal SCFAs, and immunoglobulin A (IgA) in the diverted colon. Eight patients underwent operative procedures for colostomies. We assessed the diverted colon using endoscopy and obtained intestinal samples from the diverted colon and oral colon in these patients. We analyzed the microbiota and SCFAs of the intestinal samples. The bacterial communities were investigated using a 16S rRNA gene sequencing method. The microbiota demonstrated a change in the proportion of some species, especially Lactobacillus, which significantly decreased in the diverted colon at the genus level. We also showed that intestinal SCFA values were significantly decreased in the diverted colon. Furthermore, intestinal IgA levels were significantly increased in the diverted colon. This study was the first to show that intestinal SCFAs were significantly decreased and intestinal IgA was significantly increased in the diverted colon. Our data suggest that SCFAs affect the microbiota and may play an immunological role in diversion colitis. 相似文献
772.
A synthesis of a new modified nucleoside isolated from tRNA2Gly of Bombyx mori was accomplished. This synthesis confirmed its structure and proved its absolute configuration to be 5-(S-carboxy(hydroxy)methyl)uridine. 相似文献
773.
Terminal heterogeneity and corrections of the nucleotide sequence of 5S rRNA from an extreme thermophile, Thermus thermophilus HB8 总被引:2,自引:2,他引:0
The nucleotide sequence of 5S rRNA from an extreme thermophile Thermusthermophilus HB8 has been re-examined and determined as [Formula: see text] The present study could resolve previously ambiguous residues and find two additional residues (G(8 3), C(9 7)), G at position 89 and two terminal heterogeneities which are exactly the same as reported with Thermusaquaticus 5S rRNA.Images 相似文献
774.
Three kinds of low-molecular weight alginic acid fractions, Alg.A, B, and C, were prepared from a commercial alginic acid by acid hydrolysis using phosphoric acid. Alg.A was obtained as an insoluble fraction by the filtration of mixture. Alg.B was obtained as a precipitate by pouring the filtered solution into water. Alg.C was obtained as a precipitate by pouring the filtrate into methanol. Measurements with 13C NMR, GPC and WAXS were performed on the prepared fractions for characterization.
Alg.A was composed of rich M and G blocks, and had DPn and DPw/DPn values of 79 and 3.11, respectively. Alg.B was mainly composed of M block, and had DPn and DPw/DPn values of 38 and 2.57, respectively. Alg.C had a random structure including many alternating sequences, and had DPn and DPw/DPn values of 35 and 2.11, respectively. Alginic acid oligomers prepared in this study, Alg.B and C, were improved regarding in solubility in water and the viscosity of their aqueous solution. 相似文献
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Jumpei Uchiyama Mohammad Rashel Yoshihiro Maeda Iyo Takemura Shigeyoshi Sugihara Kazue Akechi Asako Muraoka Hiroshi Wakiguchi Shigenobu Matsuzaki 《FEMS microbiology letters》2008,278(2):200-206
Vancomycin-resistant Enterococcus faecalis (VRE) has become a significant threat in nosocomial settings. Bacteriophage (phage) therapy is frequently proposed as a potential alternative therapy for infections caused by this bacterium. To search for candidate therapeutic phages against Enterococcus faecalis infections, 30 Enterococcus faecalis phages were isolated from the environment. One of these, virulent phage phiEF24C, which has a broad host range, was selected for analysis. The plaque-forming ability of phiEF24C was virtually unaffected by differences in the clinical host strains. Furthermore, the phage had a shorter latent period and a larger burst size than ordinary tailed phages, indicating that phiEF24C has effective lytic activity against many Enterococcus faecalis strains, including VRE. Morphological and genomic analyses revealed that phiEF24C is a large myovirus (classified as family Myoviridae morphotype A1) with a linear double-stranded DNA genome of c. 143 kbp. Analyses of the N-terminal amino acid sequences of the virion proteins, together with the morphology and the genome size, speculated that phiEF24C is closely related to other myoviruses of Gram-positive bacteria that have been used experimentally or practically for therapy or prophylaxis. Considering these results, phiEF24C may be a potential candidate therapeutic phage against Enterococcus faecalis infections. 相似文献
780.