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Biological material is routinely collected at crime scenes and from exhibits and is a key type of evidence during criminal investigations. Touch or trace DNA samples from surfaces and objects deemed to have been contacted are frequently collected. However, a person of interest may not leave any traces on contacted surfaces, for example, if wearing gloves. A novel means of sampling human DNA from air offers additional avenues for DNA collection. In the present study, we report on the results of a pilot study into the prevalence and persistence of human DNA in the air. The first aspect of the pilot study investigates air conditioner units that circulate air around a room, by sampling units located in four offices and four houses at different time frames post-cleaning. The second aspect investigates the ability to collect human DNA from the air in rooms, with and without people, for different periods of time and with different types of collection filters. Results of this pilot study show that human DNA can be collected on air conditioner unit surfaces and from the air, with air samples representing the more recent occupation while air conditioner units showing historic use of the room.
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ADN , Manejo de Especímenes , Humanos , ADN/análisis , Proyectos Piloto , Manejo de Especímenes/métodos , Aire/análisis , Aire AcondicionadoRESUMEN
In intracellular transports, motor proteins transport macromolecules as cargos to desired locations by moving on biopolymers such as microtubules. Recent experiments suggest that, while moving in crowded environments, cargos that can associate motor proteins during their translocation have larger run-length and association time compared to free motors. Here, we model the dynamics of a cargo that can associate at the most m free motors present on the microtubule track as obstacles to its motion. The proposed models display competing effects of association and crowding, leading to a peak in the run-length with the free-motor density. For m = 2 and 3, we show that this feature is governed by the largest eigenvalue of the transition matrix describing the cargo dynamics. In all the above cases, free motors are assumed to be present on the microtubule as stalled obstacles. We finally compare simulation results for the run-length for general scenarios where the free motors undergo processive motion in addition to binding and unbinding to or from the microtubule.
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Microtúbulos , Modelos Biológicos , Proteínas Motoras Moleculares , Microtúbulos/metabolismo , Microtúbulos/química , Proteínas Motoras Moleculares/metabolismo , Proteínas Motoras Moleculares/química , Transporte BiológicoRESUMEN
Self-assembly of ethylene oxide (EO)-propylene oxide (PO)-based star-shaped block copolymers (BCPs) in the presence of different kinds of additives is investigated in an aqueous solution environment. Commercially available four-armed BCPs, namely Tetronics® (normal: T904 with EO as the terminal end block; and reverse: T90R4 with PO as the terminal end block), each with 40%EO, are used. The effect of various additives such as electrolytes (NaCl and Na2SO4), nonelectrolyte polyols (glucose and sorbitol), and ionic surfactants (viz. anionic-sodium dodecyl sulfate (SDS), cationic-dodecyltrimethylammonium bromide (DTAB) and zwitterionic dodecyldimethylammonium propane sulfonate (C12PS)) on these BCPs is examined to observe their influence on micellization behaviour. The presence of salts and polyols displayed interesting phase behaviour, i.e., the cloud point (CP) was decreased, the water structure was affected and the micelles were dehydrated by expelling water molecules, and thus they were likely to promote micelle formation/growth. In contrast, ionic surfactants in small amounts interacted with the BCPs and showed an increase in CPs thereby forming mixed micelles with increasing charges and decreasing micellar sizes, finally transforming to small surfactant-rich mixed micelles. Molecular interactions such as electrostatic and hydrogen bonding involved within the examined entities are put forth employing a computational simulation approach using the Gaussian 09 window for calculation along with the GaussView 5.0.9 programming software using the (DFT)/B3LYP method and 3-21G basis set. The hydrodynamic diameter (Dh) of the micelles is examined using dynamic light scattering (DLS), while the various micellar parameters inferring the shape/geometry are obtained using small-angle neutron scattering (SANS) by the best fitting of the structure factors. It is observed that 10 w/v% T904 remains as spherical micelles with some micellar growth under physiological conditions (37 °C), while 10 w/v% T90R4 remains as unimers and forms spherical micelles in the presence of additives at 37 °C. Furthermore, the additive-induced micellar systems are tested as developing nanovehicles for anticancer (curcumin, Cur) drug solubilization using UV-vis spectroscopy, which shows a prominent increase in absorbance with enhanced solubilization capacity. Additionally, the cytotoxic effect of Cur loaded on the BCP micelles in HeLa cells is studied through confocal microscopy by capturing fluorescence images that depict HeLa cell growth inhibition under the influence of additive-induced micellar systems.
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Heart problems are quite prevalent worldwide. Cardiomyocytes and stem cells are two examples of the cells and supporting matrix that are used in the integrated process of cardiac tissue regeneration. The objective is to create innovative materials that can effectively replace or repair damaged cardiac muscle. One of the most effective and appealing 3D/4D scaffolds for creating an appropriate milieu for damaged tissue growth and healing is hydrogel. In order to successfully regenerate heart tissue, bioactive and biocompatible hydrogels are required to preserve cells in the infarcted region and to bid support for the restoration of myocardial wall stress, cell survival and function. Heart tissue engineering uses a variety of hydrogels, such as natural or synthetic polymeric hydrogels. This article provides a quick overview of the various hydrogel types employed in cardiac tissue engineering. Their benefits and drawbacks are discussed. Hydrogel-based techniques for heart regeneration are also addressed, along with their clinical application and future in cardiac tissue engineering.
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Introduction Oral manifestations have been observed with this condition; however, little is known about their impact on the healthcare professionals routinely managing these patients.Aims To investigate the prevalence of the oral manifestations of long COVID and the healthcare professionals' views, experiences and practices for managing these conditions.Materials and methods A cross-sectional mixed-methods study, including a self-reported online questionnaire (n = 104) and healthcare professionals' (n = 7) semi-structured interviews, was conducted. Descriptive statistics and reflexive thematic analysis were used to analyse the data.Results In total, 78% of respondents reported one or more oral conditions associated with COVID-19. Changes in the sense of taste and/or smell (58%), dry mouth (48.1%) and mouth sores (45.7%) were frequently reported. Themes identified from healthcare professionals' interviews were areas for research, management and interdisciplinary collaboration.Discussion Allied healthcare professionals may assist dental professionals with managing oral manifestations of long COVID. Inadequate access to NHS dentistry is deterring patients worried about their oral symptoms and the limited oral knowledge of healthcare professionals affects their ability to manage patients.Conclusion Healthcare professionals have observed oral manifestations in individuals diagnosed with long COVID; however, further information and training on this topic would assist them with managing patients and increasing awareness among clinicians.
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COVID-19 , Síndrome Post Agudo de COVID-19 , Humanos , Estudios Transversales , COVID-19/epidemiología , Investigación Cualitativa , Personal de Salud , Actitud del Personal de SaludRESUMEN
The application of CAD-CAM (Computer-Aided Design and Computer-Aided Manufacturing) technology has become increasingly prevalent in dentistry in recent years. Dental restorations are designed and created using CAD-CAM by enhancing the precision and efficiency. Customization of dental prostheses such as crowns, veneers, inlays, onlays and bridges is possible with CAD-CAM.
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Hospital-acquired infections are considered a priority for public health systems since they pose a significant burden for society. High-touch surfaces of healthcare centers, including textiles, provide a suitable environment for pathogenic bacteria to grow, necessitating incorporating effective antibacterial agents into textiles. This paper introduces a highly durable antibacterial gel-like solution, Silver Shell™ finish, which contains chitosan-bound silver chloride microparticles. The study investigates the coating's environmental impact, health risks, and durability during repeated washing. The structure of the Silver Shell™ finish was studied using transmission electron microscopy (TEM) and energy-dispersive X-ray spectroscopy (EDX). The TEM images showed a core-shell structure, with chitosan forming a protective shell around groupings of silver microparticles. The field-emission scanning electron microscopy (FESEM) demonstrated the uniform deposition of Silver Shell™ on the surfaces of the fabrics. AATCC Test Method 100 was employed to quantitatively analyze the antibacterial properties of the fabrics coated with silver microparticles. Two types of bacteria, Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli), were used in this study. The antibacterial results showed that after 75 wash cycles, a 100% reduction for both S. aureus and E. coli in the coated samples using crosslinking agents was observed. The coated samples without a crosslinking agent exhibited 99.88% and 99.81% reductions for S. aureus and E. coli after 50 washing cycles. To compare the antibacterial properties toward non-pathogenic and pathogenic strains of the same species, MG1655 model E. coli strain (ATCC 29213) and a multidrug-resistant clinical isolate were used. The results showed the antibacterial efficiency of the Silver ShellTM solution (up to 99.99% reduction) coated on cotton fabric. AATCC-147 was performed to investigate the coated samples' leaching properties and the crosslinking agent's effects against S. aureus and E. coli. All coated samples demonstrated remarkable antibacterial efficacy, even after 75 wash cycles. The crosslinking agent facilitated durable attachment between the silver microparticles and cotton substrate, minimizing the release of particles from the fabrics. Color measurements were conducted to assess the color differences resulting from the coating process. The results indicated fixation values of 44%, 32%, and 28% following 25, 50, and 75 washing cycles, respectively.
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Hospital-acquired infections are considered a priority for public health systems, which poses a significant burden for society. High-touch surfaces of healthcare centers, including textiles, provide a suitable environment for pathogenic bacteria to grow, necessitating incorporating effective antibacterial agents into textiles. This paper introduces a highly durable antibacterial gel-like solution, Silver Shell finish, which contains chitosan-bound silver chloride microparticles. The study investigates the coating's environmental impact, health risks, and durability during repeated washing. The structure of the Silver Shell finish was studied using Transmission Electron Microscopy (TEM) and Energy-Dispersive X-ray Spectroscopy (EDX). TEM images showed a core-shell structure, with chitosan forming a protective shell around groupings of silver micro-particles. Field Emission Scanning Electron Microscopy (FESEM) demonstrated the uniform deposition of Silver Shell on the surface of fabrics. AATCC Test Method 100 was employed to quantitatively analyze the antibacterial properties of fabrics coated with silver microparticles. Two types of bacteria, Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) were used in this study. The antibacterial results showed that after 75 wash cycles, a 100% reduction for both S. aureus and E. coli in the coated samples using crosslinking agents was observed. The coated samples without a crosslinking agent exhibited a 99.88% and 99.81% reduction for S. aureus and E. coli after 50 washing cycles. AATCC-147 was performed to investigate the coated samples' leaching properties and the crosslinking agent's effect against S. aureus and E. coli. All coated samples demonstrated remarkable antibacterial efficacy even after 75 wash cycles.