285 research outputs found
Molecular Simulation Analysis of the Structure Complex of C2 Domains of DKK Family Members and β-propeller Domains of LRP5/6:Explaining Why DKK3 Does Not Bind to LRP5/6
Dickkopf (DKK) proteins interact with low-density lipoprotein receptor-related protein 5/6 (LRP5/6) to modulate WNT signaling. The interaction is mediated by a cysteine-rich domain (C2) in the DKK protein and β-propeller domains (PD) of LRP5/6. However, the third member of the DKK family (DKK3) does not bind to LRP5/6. To determine why DKK3 does not bind to the receptor domains, we performed a molecular modeling simulation study including homology modeling, protein-protein docking and molecular dynamics (MD). The computed affinities (ΔGbinding) between the C2 and PD models were consistent with the previously reported experimental results. The C2 model of DKK3 showed the lowest affinity for PD models. Multiple sequence alignment of C2 domains revealed that the DKK3 genes have a unique 7-amino-acid insertion (L249-E255 in human DKK3) and P258 in a finger loop 1 (FL1). Interestingly, the insertion sequence is evolutionally conserved. MD simulations of high-affinity complex models of C2 and PD showed that FL1 directly interacts with the PD models and stabilizes the complex models. We also built a 7-amino-acid-deletion/P258G mutant model of DKK3C2 and estimated its affinities for the PD models. The affinity for human LRP5PD2 was increased by the substitution
(ΔGbinding=-48.9kcal/mol) and the affinity was compatible with that of high-affinity ligands. The results suggested that the lack of affinity between human DKK3 and human LRP5/6 results from:
i) insertion of the 7 amino acids, and ii) P258 in human DKK3. The sequence differences thus suggest an explanation for this unique property of DKK3
Investigation of Bacteria from Spoiled Bottled Salad Dressing Leading to Gas Explosion
Background: In 2020, an incident involving spoiled salad dressing from a commercial source occurred. Upon opening the bottle, the contents exploded from gas that seemed to have fermented inside the bottle. For safety concerns, we sought to investigate the bacteria from the salad dressing in order to notify the company that made the product and relevant authorities. Methods: Anaerobic and carbon dioxide culture methods were used. To determine species of colonies, MALDI-TOF-MS and 16S rRNA whole sequencing were performed. Results: There were no colonies grown in anaerobic condition; however, we obtained three colonies from the carbon dioxide atmosphere. We determined the first colony as Alkalihalobacillus clausii (Bacillus clausii), the second as Bacillus spp. such as B. australimaris, B. safensis or B. safensis subsp. osmophilus and the third as B. paralicheniformis. Phylogenic tree analysis using the16S rRNA sequence revealed these colonies to be in a proximity of known gas-producing species. The NCBI database search revealed that a key gas production pathway gene, pyruvate formate-lyase (pfl), of which the gene product catalyzes pyruvate to formate conversion, exists in B. paralicheniformis. Formate dehydrogenase (FdhH) produces CO2 from formate that the coding gene fdhF positive bacteria can participate in gas production when formate is present in the culture. And we found fdhF from A. clausii, B. australimaris/B. safensis and B. paralicheniformis. Furthermore, under butanediol producing pathway, genes coding two enzymes involved in CO2 production, namely als and ald, existed in B. australimaris/B. safensis and B paralicheniformis, whereas A. clausii possessed als. Conclusion: Candidate species A. clausii, B. australimaris/B. safensis and B. paralicheniformis from spoiled salad dressing were thought to produce CO2 gas each from their own enzymes, or in combination, which caused the explosion upon opening. The endospore forming nature of Bacillus should alert us to be cautious when considering food producing process regulations where we need to thoroughly heat any product during manufacture in order to inactivate any bacteria as there is the possibility of this type of dangerous occurrence
Functional Significance of Facilitation Between the Pronator Teres and Extensor Carpi Radialis in Humans: Studies with Electromyography and Electrical Neuromuscular Stimulation
ニホン ノ エイゴ ジュギョウ ニオケル タスク カツドウ ノ トクチョウ ト カダイ ショウガッコウ チュウガッコウ ノ タスク カツドウ ノ ブンセキ オ トオシテ
The purpose of this paper is to describe the characteristics of task activities in Japanese English Classes. In order to achieve this goal, first, six dimensions which influenced the definition of task activities were clarified. And based on these, a research framework to analyze task activities in Japanese English classes was established. Within this framework, the task activities in both primary and junior high school English classes were analyzed from the following. six viewpoints 1) the scope of a task, 2) the perspective from which a task is viewed, 3) the authenticity of a task, 4) the linguistic skills required to perform a task, 5) the improvisation of a task, and 6) the outcome of a task. In short, the results showed that task activities in Japanese English classes involved various types of communication practices such as playing games and making videotaped conversations for foreign students, but these activities had limited communication patterns. Finally, some issues and pedagogical implications were addressed in order to lead to further efficient English practices with task activities.国立情報学研究所『研究紀要公開支援事業』により電子化
Usefulness of the waterless method for surgical hand washing:A comparison with the conventional scrub method
To evaluate the usefulness of the waterless hand washing method for surgical anti-sepsis, we conducted a microbial sampling study, comparing it to a conventional surgical scrub method. A total of 18 operating-room nurses were undertaking the following three-hand washing protocols : scrubbing with blushes using 4w/v% chlorhexidine gluconate (CHG) and also rubbing with CHG, followed by application of a 0.2w/v% CHG with ethanol (HS) preparation. (conventional method); rubbing with CHG and application of HS (two-stage surgical scrub method; TSS); rubbing with anti-septic soap and application of HS (waterless method; WL). Microbial sampling was conducted after hand washing using the glove juice method. No statistically significant differences in bacterial numbers were found among these three methods. The number of bacterially positive subjects was significantly higher in the conventional method than the TSS method. These results indicate that there are adverse effects of blush-scrubbing, as the detected bacteria were related to normal skin flora. As such, the WL method for hand anti-sepsis appears to be equivalent to the conventional surgical scrubbing method in terms of microbial detection. The WL method should therefore be introduced as a standard hand anti-sepsis method at the time of surgery because it is cost-effective as well as time-efficient
Visual Feature Integration of Three Attributes in Stimulus-Response Mapping Is Distinct From That of Two
In the human visual system, different attributes of an object are processed separately and are thought to be then temporarily bound by attention into an integrated representation to produce a specific response. However, if such representations existed in the brain for arbitrary multi-attribute objects, a combinatorial explosion problem would be unavoidable. Here, we show that attention may bind features of different attributes only in pairs and that bound feature pairs, rather than integrated object representations, are associated with responses for unfamiliar objects. We found that in a mapping task from three-attribute stimuli to responses, presenting three attributes in pairs (two attributes in each window) did not significantly complicate feature integration and response selection when the stimuli were not very familiar. We also found that repeated presentation of the same triple conjunctions significantly improved performance on the stimulus-response task when the correct responses were determined by the combination of three attributes, but this familiarity effect was not observed when the response could be determined by two attributes. These findings indicate that integration of three or more attributes is a distinct process from that of two, requiring long-term learning or some serial process. This suggests that integrated object representations are not formed or are formed only for a limited number of very familiar objects, which resolves the computational difficulty of the binding problem
選択的セロトニン再取り込み阻害薬とセロトニン4受容体作動薬の直腸吻合部におけるインビボ神経再建に与える効果の比較
It was recently reported that activation of enteric neural 5-HT(4) receptors (SR4) promotes reconstruction of enteric neural circuit injury in distal gut of guinea pigs and that this reconstruction involves neural stem cells. We aimed to explore a novel approach using a selective serotonin reuptake inhibitor (SSRI), which increases endogenous 5-HT, to repair enteric nerve fiber injury in the rat distal gut. Enteric nerve fiber injury was performed by rectal transection and subsequent end-to-end one-layer anastomosis. The SSRI fluvoxamine maleate (100 μmol/l) was applied locally at the anastomotic site to compare with the 5-HT(4) agonist mosapride citrate (100 μmol/l) (applied for patent) applied locally and orally. Unlike mosapride, fluvoxamine failed to promote the regeneration of the nerve fiber tract across the anastomosis. Furthermore, fluvoxamine did not generate anti-distal-less homeobox 2 (DLX2)- and anti-SR4-positive cells (neural stem cells) and/or anti-neurofilament (NF)-positive cells (neural cells) in newly formed granulation tissue at the anastomosis, whereas these cell types were observed in mosapride-treated preparations. In contrast to its effects in guinea pigs, mosapride generated 5-bromo-2'-deoxyuridine (BrdU)-positive neural cells in ganglia sites 3 mm oral and anal from the anastomosis 2 wk after nerve fiber injury. All actions of mosapride were observed after local and or oral applications. These findings indicate that local SSRI treatment does not induce in vivo nerve fiber tract growth across the anastomosis in the rat distal gut. Mosapride induces nerve fiber tract growth across the anastomosis, mediated through enteric neural stem cells possibly from neural crest-derived stem cells or mesenchymal stem cells in the bone marrow.博士(医学)・甲616号・平成26年3月17日発行元の規定により、本文の登録不可。本文は以下のURLを参照 "http://dx.doi.org/10.1152/ajpgi.00284.2011
Methanol and Butanol Extracts of Paeonia lutea
Squamous cell carcinoma (SCC) is one of the most common cancers of the head and neck region worldwide and is generally treated surgically in combination with radiotherapy and/or chemotherapy. However, anticancer agents have numerous serious side effects, and alternative, less toxic agents that are effective as chemotherapeutics for SCC are required. The Paeoniaceae family is widely used in traditional Chinese medicine. We examined methanol and butanol extracts of Paeonia lutea (P. lutea) leaves for their potential as an anticancer agent. Both extracts decreased the proliferation of SCC cells, induced apoptotic cell death, and modulated migration, adhesion, chemotaxis, and haptotaxis in an extracellular matrix- (ECM-) dependent manner due to altered expression of several integrin subunits. Subsequently, SCC cells were subcutaneously transplanted into athymic nude mice; the extracts reduced the metastasis of SCC cells but had little effect on the volume of the primary tumor or survival or body weight of the mice. The results suggest that the extracts may hold promise for preventing cancer metastasis
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