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A bacteriophage BD49 specific for Citrobacter braakii was screened out and purified by double-layer plate method. It consists of a polyhedral head of 93.1 ± 1.2 nm long and 72.9 ± 4.2 nm wide, tail fibers, collar, sheath and baseplate. The bacteriophage was identified by morphology observed with transmission electron microscope (TEM), whole genome sequencing carried out by Illumina next generation sequencing (NGS) technique, and gene annotation based on Clusters of Orthologous Groups of proteins (COG) database. It was identified primarily as a member of Caudovirales by morphology and further determined as Caudovirales, Myoviridae, and Citrobacter bacteriophage by alignment of its whole genome sequence with the NCBI database and establishment of phylogenetic tree. The bacteriophage showed good environmental suitability with optimal multiplicity of infection (MOI) of 0.01, proliferation time of 80 min, optimum living temperature of 30-40 °C, and living pH of 5-10. In addition, it exhibited synergistic effect with ciprofloxacin against C. braakii in antibacterial tests.
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Antibacterianos , Bacteriófagos , Antibacterianos/farmacologia , Bacteriófagos/genética , Filogenia , Citrobacter/genéticaRESUMO
Mechanochromic functionality realized via the force-responsive mechanophores in polymers has great potential for damage sensing and information storage. Mechanophores with the ability to recognize multiple stimuli for tunable chromic characteristics are highly sought after for versatile sensing ability and color programmability. Nevertheless, the majority of mechanophores are based on single-component chromophores with limited sensitivity, or require additional fabrication technology for multi-modal chromism. Here, we report a novel multifunctional mechanophore capable of vividly detectable and tunable mechanochromism in polymers. This synergistic optical coupling relies on strategically fusing rhodamine and spiropyran (Rh-SP), and tethering polymer chains on both subunits. The mechanochromic behaviors of the Rh-SP-linked polymers under sonication and compression are thoroughly evaluated in response to changes in force and the light-controlled relaxation process. Non-sequential ring-opening of the two subunits under force is identified, endowing high-contrast mechanochromism. Light-induced differential ring-closing reactions of the two subunits, together with the acidichromism of the SP moiety, are employed to engineer elastomers with programmable and wide-spectrum colors. Our work presents an effective strategy for highly appreciable and regulable mechanochromic functionality, and also provides new insights into the rupture mechanisms of π-fused mechanophores, as well as how the stimuli history controls stress accumulation in polymers.
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The aggregation of monomeric amyloid ß protein (Aß) into oligomers and amyloid plaque in the brain is associated with Alzheimer's disease. The hydrophobic central core Aß16-22 has been widely studied due to its essential role in the fibrillization of full-length Aß peptides. Compared to the homogeneous antiparallel structure of Aß16-22 at the late stage, the early-stage prefibrillar aggregates contain varying proportions of different ß structures. In this work, we studied the appearance probabilities of various self-assembly structures of Aß16-22 and the effects of Zn2+ on these probabilities by replica exchange molecular dynamics simulations. It was found that at room temperature, Aß16-22 can readily form assembled ß-sheet structures in pure water, where a typical antiparallel arrangement dominates (24.8% of all sampled trimer structures). The addition of Zn2+ to the Aß16-22 solution will dramatically decrease the appearance probability of antiparallel trimer structures to 12.5% by disrupting the formation of the Lys16-Glu22 salt bridge. Meanwhile, the probabilities of hybrid antiparallel/parallel structures increase. Our simulation results not only reveal the competition between antiparallel and parallel structures in the Aß16-22 oligomers but also show that Zn2+ can affect the oligomer structures. The results also provide insights into the role of metal ions in the self-assembly of short peptides.
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Doença de Alzheimer , Peptídeos beta-Amiloides , Humanos , Peptídeos beta-Amiloides/química , Doença de Alzheimer/metabolismo , Simulação de Dinâmica Molecular , Conformação Proteica em Folha beta , Zinco , Fragmentos de Peptídeos/químicaRESUMO
Traditional mining practices not only cause severe environmental issues, but also face the problem of insufficient production capacity of gold to meet its growing demand. The proposed alternative strategies for gold production, such as the extraction of gold from seawater, still keep a formidable challenge due to their strong dependence on adsorbent materials with high capacity, selectivity, and sensitivity, while also needing to meet the demands of being environmentally friendly and cost-effective. In practice, the direct extraction of gold from seawater is limited by its extremely low yield and high energy expenditure. However, if the combination of gold extraction techniques with seawater desalination can substantially reduce the energy consumption, the extraction of gold from seawater will become economical and feasible. In this paper, we evaluate the feasibility of marine gold extraction using reduced graphene oxide membranes (rGOM) during the seawater desalination process. The rGOM can adsorb almost all Au3+ from the solutions with trace concentrations of Au3+ ranging from 10 ppb to 200 ppb. The adsorption quantity is linearly related to the concentration, indicating that the adsorption capacity of rGOM is much higher than the total amount of Au3+ in the solution. Additionally, the rGOM can selectively adsorb 99 % of Au3+ in the mixed solution while hardly adsorbing other common elements in seawater. More importantly, the rGOM exhibits the long-term stability over 30 days when being immersed in the solution, making it directly compatible with the existing seawater desalination processes. These specific properties allow the rGOM to be an ideal candidate for combining the extraction of gold from seawater with seawater desalination processes. Our findings provide a methodology for enhancing the economic efficiency of the extraction of gold from seawater and hold promise for addressing the problem of gold scarcity.
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Recommendations on the use of acupuncture in managing low back pain (LBP) vary across different guidelines. The methodological quality of existing systematic reviews and meta-analyses on this topic also demonstrates considerable diversity, potentially leading to biased conclusions. Therefore, we comprehensively searched PubMed, EMBASE, Web of Science, Cochrane Database of Systematic Reviews, and Chinese National Knowledge Infrastructure (CNKI) databases and conducted an umbrella review. Scrutiny was performed to ascertain whether primary studies within the systematic reviews and meta-analyses adhered to our inclusion criteria, followed by a meticulous reanalysis of pertinent data. Participant numbers, heterogeneity, publication bias, and excessive significance were taken into account when assessing the credibility of the evidence. For robustness, sensitivity analysis was performed using the leave-one-out method. The results of the umbrella review yielded highly suggestive evidence in favor of the immediate and short-term analgesic effects of acupuncture, with suggestive evidence supporting intermediate-term analgesic effects. However, the effectiveness of acupuncture on disability improvement has demonstrated weak to suggestive evidence. Evidence supporting the enhancement of quality of life by acupuncture is limited. The leave-one-out analysis corroborated the robustness of the meta-analysis, further confirming the credibility of the findings. This umbrella review indicated that the most significant advantage of acupuncture for LBP is its capacity to reduce pain.
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Terapia por Acupuntura , Dor Lombar , Humanos , Dor Lombar/terapia , Qualidade de Vida , Resultado do TratamentoRESUMO
This systematic review investigates the impact of meditation on neural responses to pain, as measured by functional magnetic resonance imaging (fMRI). Up to March 2024, we conducted searches across four databases for human studies implementing fMRI to assess the efficacy of meditation for pain relief. Eighteen studies met the inclusion criteria. Our systematic review indicates that activation of the insula, anterior cingulate cortex, and orbitofrontal cortex is positively associated with meditation for pain relief, while activity in regions like the amygdala and medial prefrontal cortex is negatively correlated with pain relief. Meta-analyses consistently reveal the involvement of various brain regions, including the insula, putamen, amygdala, anterior cingulate cortex, precentral gyrus, postcentral gyrus, inferior parietal lobule, superior temporal gyrus, inferior frontal gyrus, and caudate nucleus, in meditation-induced alleviation of pain. These findings suggest ccthat meditation acts on specific brain regions related to pain, mood, and cognition, providing insight into the potential mechanisms underlying the pain-alleviating effects of meditation on both pain sensations and emotional experiences.
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Meditação , Manejo da Dor , Humanos , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Encéfalo/fisiopatologia , Imageamento por Ressonância Magnética , Dor/fisiopatologia , Dor/diagnóstico por imagemRESUMO
This study investigated the relationship between executive functions and metacognition. Both constructs have been well-studied, but little research has focused on their connections. The goal of the current investigation was to increase the understanding of the relationship between metacognition and executive functions by assessing the relationships between metacognitive monitoring accuracy and the three component executive functions (updating, inhibition, and shifting) among college students. Metacognitive monitoring accuracy was measured using a knowledge monitoring accuracy (KMA) test. The three components of executive functions, updating, inhibition, and shifting were measured, respectively, using the ABCD updating task, the Stroop color-word interference test, and the letter-number task. The Tower of Hanoi task was used to measure the complex executive functions (inhibition and updating). Correlation and regression analyses were performed to examine the relationships. The results indicate that updating is the only component executive function that significantly correlated with metacognitive monitoring, suggesting that metacognition-specifically, metacognitive monitoring-is associated with at least one component of executive functioning.
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BACKGROUND: To investigate the application value of tumor abnormal protein in patients with type 2 diabetes mellitus complicated with lung adenocarcinoma in situ. MATERIALS AND METHODS: A total of 140 patients having type 2 diabetes mellitus complicated with lung adenocarcinoma in situ (Group A), 160 patients with type 2 diabetes mellitus (Group B), and 120 healthy controls (Group C) were enrolled in the Department of Thoracic Surgery of the First Affiliated Hospital of Soochow University from November 2021 to December 2022. RESULTS: The total cholesterol level was higher in Group A than in Group B (p < 0.05) and Group C (p < 0.01), and it was higher in Group B than in Group C (p < 0.01). The comparison results of cholesterol level were similar to those of tumor abnormal protein, low-density lipoprotein cholesterol, and glycosylated hemoglobin among the three groups. The triglyceride level was higher in Group A than in Group B and Group C (both p < 0.01). Group A had a higher level of high-density lipoprotein cholesterol than Group C (p < 0.01). The fasting plasma glucose level was higher in Group A than in Group B and Group C (both, p < 0.01). These findings indicated that tumor abnormal protein, glycosylated hemoglobin, high-density lipoprotein cholesterol, and fasting plasma glucose were independent factors for patients having type 2 diabetes mellitus complicated with lung adenocarcinoma in situ. CONCLUSION: Therefore, detecting tumor abnormal protein levels may help diagnose lung adenocarcinoma in situ in patients with type 2 diabetes mellitus.
The study found that tumor abnormal protein, glycosylated hemoglobin, high-density lipoprotein cholesterol, and fasting plasma glucose were independent factors for patients having type 2 diabetes mellitus complicated with lung adenocarcinoma in situ. Detecting tumor abnormal protein levels may help diagnose lung adenocarcinoma in situ in patients with type 2 diabetes mellitus.