74 research outputs found
Artificial Extracellular Matrix Proteins Containing Phenylalanine Analogues Biosynthesized in Bacteria Using T7 Expression System and the PEGylation
In vivo incorporation of phenylalanine (Phe) analogues into an artificial extracellular matrix protein (aECM-CS5-ELF) was accomplished using a bacterial expression host that harbors the mutant phenylalanyl-tRNA synthetase (PheRS) with an enlarged binding pocket. Although the Ala294Gly/Thr251Gly mutant PheRS (PheRS**) under the control of T5 promoter allows incorporation of some Phe analogues into a protein, the T5 system is not suitable for material science studies because the amount of materials produced is not sufficient due to the moderate strength of the T5 promoter. This limitation can be overcome by using a pair of T7 promoter and T7 RNA polymerase instead. In the T7 expression system, it is difficult, however, to achieve a high incorporation level of Phe analogues, due to competition of Phe analogues for incorporation with the residual Phe that is required for synthesis of active T7 RNA polymerase. In this study, we prepared the PheRS** under T7 promoter and optimized culture condition to improve both the incorporation level of recombinant aECM protein and the incorporation level of Phe analogues. Incorporation and expression levels tend to increase in the case of p-azidophenylalanine, p-iodophenylalanine, and p-acetylphenylalanine. We evaluated the lower critical transition temperature, which is dependent on the incorporation ratio and the turbidity decreased when the incorporation level increased. Circular dichromism measurement indicated that this tendency is based on conformational change from random coil to β-turn structure. We demonstrated that polyethylene glycol (PEG) can be conjugated at reaction site of Phe analogues incorporated. We also demonstrated that the increased hydrophilicity of elastin-like sequences in the aECM-CS5-ELF made by PEG conjugation could suppress nonspecific adhesion of human umbilical vein endothelial cells (HUVEC)
Melanotic oncocytic metaplasia of the nasopharynx as a benign mimicker of malignant melanoma: a case report
<p>Abstract</p> <p>Introduction</p> <p>Melanotic variant of oncocytic metaplasia of the nasopharynx is an extremely rare condition.</p> <p>Case report</p> <p>A 73-year-old Japanese man presented with nasal congestion and chill. Nasoscopic examination revealed multiple black nodules around the bilateral torus tubarius. The nodules were biopsied to determine the histology. The clinical differential diagnosis was malignant melanoma or hemangioma. Microscopically, there were oncocytic plump cells with abundant brown pigmented granules showing glandular pattern. No significant atypia was found. The pigment was positive for Fontana-Masson staining, and negative for Berlin blue staining, showing that it was melanin pigment. Immunohistochemically, S100-positive HMB45-negative dendritic cells were also found.</p> <p>Conclusion</p> <p>Such a pigmented variant of benign oncocytic lesion is very rare, and only 15 cases have been reported in the English literature. As a benign mimicker of malignant melanoma, melanocytic oncocytic metaplasia should be always taken into consideration in the clinical setting.</p
Importance of “meal first” strategy and effective situations of supplement use in elite athletes: Japan high performance sport center position stand
The “meal first” strategy is traditionally recommended for athletes' conditioning. However, the importance of the “meal first” principle has not been detailly well documented in athletes' lives. Supplement use has recently become a common part of athletes' diets, but unmonitored supplement use can cause negative consequences, such as anti-doping violations and health issues. Therefore, this review summarizes how the “meal first” strategy and planned supplement use are important for enhancing athletes’ health and performance. We believe that the “meal first” strategy is beneficial in terms of the following aspects: (1) consumption of multi-nutrients and other functional components simultaneously; (2) positive effects on psychological well-being; (3) contribution to athletes' health by way of mastication; and (4) less risk for anti-doping violations. Before supplement use, we recommend that athletes first verify their basic factors (e.g., diet, training, and sleep), given that the benefits of supplements are examined and demonstrated with the control of those factors. Otherwise, athletes cannot obtain maximal benefits from the supplements. In contrast, there are situations in which supplements in athletes' lives can be advantageous, such as (1) nutrient deficiency due to ongoing dietary characteristics; (2) interruption of meals due to disease; (3) inaccessibility of quality food during athletic travel; (4) difficulty preparing food due to societal restrictions associated with disasters or infection outbreaks; (5) having a meal before, during, or after exercise is difficult; and (6) achieving targeted intake of performance-enhancing ingredients is not practical. In summary, we emphasize that the “meal first” strategy is recommended for athletes' conditioning, but there are several contexts when supplement use can be more useful in athletes' lives
Factors causing climatologically high temperatures in a hottest city in Japan: a multi-scale analysis of Tajimi
In this study, multi-scale climatological features of extreme high temperature (EHT) events in Tajimi, the hottest cities in Japan, were investigated using observational data collected by the Japan Meteorological Agency over the past 23 years, and original data observed by the authors over the last 3 years. Results revealed the background factors that lead to climatologically high temperatures in Tajimi: the occurrence of a characteristic pressure pattern called ‘whale’: the synoptic-scale factors, and the urbanization of Tajimi: the meso-γ-scale factors. In addition, the high temperatures measured in Tajimi are affected by the foehn-like westerly airflow coming from the mountains located in the northwest/west towards the Nobi Plain where Tajimi is located at the east end: the meso-β-scale factors, and the location of the Tajimi observation site, which is within an urbanized area where the highest temperatures tend to be observed: the micro-scale factors. In contrast, statistical analysis demonstrated that the small-scale basin effects and soil dryness around Tajimi were of lesser importance than aforementioned factors, in the occurrence of EHT events in Tajimi
Seismicity controlled by resistivity structure : the 2016 Kumamoto earthquakes, Kyushu Island, Japan
The M JMA 7.3 Kumamoto earthquake that occurred at 1:25 JST on April 16, 2016, not only triggered aftershocks in the vicinity of the epicenter, but also triggered earthquakes that were 50–100 km away from the epicenter of the main shock. The active seismicity can be divided into three regions: (1) the vicinity of the main faults, (2) the northern region of Aso volcano (50 km northeast of the mainshock epicenter), and (3) the regions around three volcanoes, Yufu, Tsurumi, and Garan (100 km northeast of the mainshock epicenter). Notably, the zones between these regions are distinctively seismically inactive. The electric resistivity structure estimated from one-dimensional analysis of the 247 broadband (0.005–3000 s) magnetotelluric and telluric observation sites clearly shows that the earthquakes occurred in resistive regions adjacent to conductive zones or resistive-conductive transition zones. In contrast, seismicity is quite low in electrically conductive zones, which are interpreted as regions of connected fluids. We suggest that the series of the earthquakes was induced by a local accumulated stress and/or fluid supply from conductive zones. Because the relationship between the earthquakes and the resistivity structure is consistent with previous studies, seismic hazard assessment generally can be improved by taking into account the resistivity structure. Following on from the 2016 Kumamoto earthquake series, we suggest that there are two zones that have a relatively high potential of earthquake generation along the western extension of the MTL
Functional annotation of human long noncoding RNAs via molecular phenotyping
Long noncoding RNAs (lncRNAs) constitute the majority of transcripts in the mammalian genomes, and yet, their functions remain largely unknown. As part of the FANTOM6 project, we systematically knocked down the expression of 285 lncRNAs in human dermal fibroblasts and quantified cellular growth, morphological changes, and transcriptomic responses using Capped Analysis of Gene Expression (CAGE). Antisense oligonucleotides targeting the same lncRNAs exhibited global concordance, and the molecular phenotype, measured by CAGE, recapitulated the observed cellular phenotypes while providing additional insights on the affected genes and pathways. Here, we disseminate the largest-todate lncRNA knockdown data set with molecular phenotyping (over 1000 CAGE deep-sequencing libraries) for further exploration and highlight functional roles for ZNF213-AS1 and lnc-KHDC3L-2.Peer reviewe
Artificial Extracellular Matrix Proteins Containing Phenylalanine Analogues Biosynthesized in Bacteria Using T7 Expression System and the PEGylation
Comparative genomics of the tardigrades <i>Hypsibius dujardini</i> and <i>Ramazzottius varieornatus</i>
Tardigrada, a phylum of meiofaunal organisms, have been at the center of discussions of the evolution of Metazoa, the biology of survival in extreme environments, and the role of horizontal gene transfer in animal evolution. Tardigrada are placed as sisters to Arthropoda and Onychophora (velvet worms) in the superphylum Panarthropoda by morphological analyses, but many molecular phylogenies fail to recover this relationship. This tension between molecular and morphological understanding may be very revealing of the mode and patterns of evolution of major groups. Limnoterrestrial tardigrades display extreme cryptobiotic abilities, including anhydrobiosis and cryobiosis, as do bdelloid rotifers, nematodes, and other animals of the water film. These extremophile behaviors challenge understanding of normal, aqueous physiology: how does a multicellular organism avoid lethal cellular collapse in the absence of liquid water? Meiofaunal species have been reported to have elevated levels of horizontal gene transfer (HGT) events, but how important this is in evolution, and particularly in the evolution of extremophile physiology, is unclear. To address these questions, we resequenced and reassembled the genome of H. dujardini, a limnoterrestrial tardigrade that can undergo anhydrobiosis only after extensive pre-exposure to drying conditions, and compared it to the genome of R. varieornatus, a related species with tolerance to rapid desiccation. The 2 species had contrasting gene expression responses to anhydrobiosis, with major transcriptional change in H. dujardini but limited regulation in R. varieornatus. We identified few horizontally transferred genes, but some of these were shown to be involved in entry into anhydrobiosis. Whole-genome molecular phylogenies supported a Tardigrada+Nematoda relationship over Tardigrada+Arthropoda, but rare genomic changes tended to support Tardigrada+Arthropoda
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