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Different nanostructured surfaces have bactericidal properties that arise from the interaction between the bacteria and the nanostructured surface. In this study, we focused on the relationship between bacterial motility and bactericidal properties. The motility of Escherichia coli (E. coli) was tuned by genetic engineering, and four types of E. coli (wild type (WT), lacking flagella, and flagellated with deficient motility or deficient chemotaxis) were used to evaluate the adhesion and bactericidal properties of nanostructured surfaces. Cicada (Cryptotympana facialis) wings and Si nano-pillar array substrates were used as natural and artificial nanostructured surfaces, respectively. Differences in motility and chemotaxis strongly influenced the adhesion behavior and to some extent, the damage to the cell membrane. These results suggest that the bactericidal properties of nanostructured surfaces depend on bacterial motility.

Bactericidal effect derived from nanostructured surface was evaluated in the point of view of the motility of E. coli. The results suggest that the properties strongly depend on bacterial motility.  相似文献   
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Although 80% of individuals infected with the severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) recover without antiviral treatments, the other 20% progress to severe forms of pulmonary disease, suggesting that the host’s immune response to the virus could influence the outcome of coronavirus disease 2019 (COVID-19). SARS-CoV-2 infects alveolar epithelial type 2 cells expressing angiotensin-converting enzyme 2, and these infected epithelial cells recruit dendritic cells, neutrophils and monocytes /macrophages, leading to the activation of CD4+ and CD8+ T cells. These cells launch an antiviral immune response, but are able to completely suppress viral replication or completely eradicate virus in a limited proportion of infected patients. In other patients, viral suppression is incomplete and the numbers of circulating B and T cells are subsequently reduced by as yet unknown mechanisms. Some patients with sustained viral replication progress to a severe condition called cytokine storm. Although antiviral drug(s) should be considered early in infection to prevent progression, there have been no antiviral therapies proven to be effective for significantly inhibiting the viral replication in vivo and suppressing the progression to cytokine storm. Blocking the action of cytokines with dexamethasone or anti-interleukin-6 could have a pivotal role in treatment of those patients. Therapeutic strategy should therefore be based on viral kinetics and the immunopathology of COVID-19.  相似文献   
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Endovascular therapy is strongly recommended for acute cerebral large vessel occlusion (LVO) with an Alberta stroke program early computed tomography score (ASPECTS) ≥6 due to occlusion of the internal carotid artery or M1 segment of the middle cerebral artery. However, the effect of endovascular therapy for patients with a large ischemic core with an ASPECTS ≤5 (0–5) was not established. A multicenter, randomized, open-label, parallel-group trial was conducted to investigate the superiority of endovascular therapy over medical therapy without endovascular therapy for a large ischemic core with ASPECTS (3–5). Patients were randomly assigned to receive endovascular therapy or without endovascular therapy at a ratio of 1:1. The primary outcome was a moderate functional outcome, defined as a modified Rankin scale (mRS; scores ranging from 0 [no symptoms] to 6 [death]) ≤3 after 90 days. The secondary outcomes were defined as ordinal mRS, good functional outcome (mRS ≤2), excellent functional outcome (mRS ≤1), mRS shift analysis after 90 days, and early improvement of neurological findings at 48 hours. A total sample size of 200 was estimated to provide a power of 0.9 with a two-sided alpha of 0.05, for the primary outcome, considering a 15% dropout rate. This randomized clinical trial reported the applicability of endovascular therapy in patients with acute cerebral LVO with a large ischemic core.  相似文献   
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Metabolic alteration is increasingly recognized as an important pathogenic process that underlies fibrosis across many organ types, and metabolically targeted therapies could become important strategies for reducing fibrosis. In present study, target enzymes that are involved in changes in phospholipid metabolism during fibroblast-to-myofibroblast transition induced by transforming growth factor beta 1 (TGF-β1) were examined. Different amounts of phospholipids were found in the 2 groups. In response to TGF-β1 stimulation, 17 lipids decreased and 17 increased. The latter included the phospholipids phosphatidylcholine (PC), phosphatidylserine (PS), and phosphatidylethanolamine (PE). Furthermore, among the rate-limiting enzymes that regulate these phospholipids, phosphatidylserine decarboxylase (PISD), which controls conversion of PS to PE and is localized in mitochondria, decreased in response to TGF-β1. Knockdown of PISD alone without TGF-β1 stimulation increased expression of α-smooth muscle actin mRNA and production of total collagen. Taken together, these results indicate that PISD is involved in the mechanism of fibrogenesis by regulating phospholipid metabolism.  相似文献   
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BackgroundEarly onset of action has become recognized as an important efficacy feature of preventive migraine treatment, which can help overcome adherence issues commonly associated with older medications. Preventive treatments that target the calcitonin gene-related peptide (CGRP) or the CGRP receptor have been previously shown to provide early onset of action.MethodsThis subanalysis of primary endpoints of two separate phase 2b/3 studies sought to determine the onset of action of fremanezumab in Japanese and Korean patients with episodic migraine (EM) and chronic migraine (CM).ResultsIn EM patients (n = 357), both fremanezumab quarterly and fremanezumab monthly led to greater reductions in weekly migraine days (days/week) than placebo from the first week after the initial injection and thereafter during the remainder of the study period. Similarly, CM patients (n = 571) had a greater reduction in headache days of at least moderate severity (days/week) with fremanezumab (total) than placebo. The percentage of patients with a migraine day (EM) or headache day at least moderate severity (CM) was lower in those treated with fremanezumab than placebo and this effect was apparent from as early as Day 2 (1 day after first injection).ConclusionsThese results suggest that fremanezumab has an early onset of action, as noted in previous post hoc analyses of anti-CGRP monoclonal antibodies.Trial registrationClinicalTrials.gov. NCT03303092, Registered 5 October 2017, NCT03303079, Registered 5 October 2017.  相似文献   
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