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It is key to fight bacterial adhesion to prevent biofilm establishment on biomaterials. Surface immobilization of antimicrobial peptides (AMP) is a promising strategy to avoid bacterial colonization. This work aimed to investigate whether the direct surface immobilization of Dhvar5, an AMP with head-to-tail amphipathicity, would improve the antimicrobial activity of chitosan ultrathin coatings. The peptide was grafted by copper-catalyzed azide-alkyne cycloaddition (CuAAC) chemistry by either its C- or N- terminus to assess the influence of peptide orientation on surface properties and antimicrobial activity. These features were compared with those of coatings fabricated using previously described Dhvar5-chitosan conjugates (immobilized in bulk). The peptide was chemoselectively immobilized onto the coating by both termini. Moreover, the covalent immobilization of Dhvar5 by either terminus enhanced the antimicrobial effect of the chitosan coating by decreasing colonization by both Gram-positive (Staphylococcus aureus, Staphylococcus epidermidis) and Gram-negative (Escherichia coli, Pseudomonas aeruginosa) bacteria. Relevantly, the antimicrobial performance of the surface on Gram-positive bacteria depended on how Dhvar5-chitosan coatings were produced. An antiadhesive effect was observed when the peptide was grafted onto prefabricated chitosan coatings (film), and a bactericidal effect was exhibited when coatings were prepared from Dhvar5-chitosan conjugates (bulk). This antiadhesive effect was not due to changes in surface wettability or protein adsorption but rather depended on variations in peptide concentration, exposure, and surface roughness. Results reported in this study show that the antibacterial potency and effect of immobilized AMP vary greatly with the immobilization procedure. Overall, independently of the fabrication protocol and mechanism of action, Dhvar5-chitosan coatings are a promising strategy for the development of antimicrobial medical devices, either as an antiadhesive or contact-killing surface. [ABSTRACT FROM AUTHOR]

This paper is an analysis of inserting history and philosophy of science (HPS) in a physics undergraduate program at a Brazilian university. It is an examination of the approaches and methodologies adopted by professors of a History and Epistemology course. The course aims to have an explicit approach to HPS. The results suggest a concern of the Physics Institute regarding inserting these questions into physics teacher training programs. The study also uncovered that the professors who taught the subject had different visions of HPS.

The major risk factor associated with the development of gastric cancer is chronic infection with Helicobacter pylori. The available treatments, based on a cocktail of antibiotics, fail in up to 40% of patients and disrupt their gut microbiota. The potential of blank nanostructured lipid carriers (NLC) for H. pylori eradication was previously demonstrated by us. However, the effect of NLC charge, size and protein corona on H. pylori-specific bactericidal activity herein studied was unknown at that time. All developed NLC formulations proved bactericidal against H. pylori. Although cationic NLC had 10-fold higher bactericidal activity than anionic NLC, they lacked specificity, since Lactobacillus acidophilus was also affected. Anionic NLC achieved complete clearance in both H. pylori morphologies (rod- and coccoid-shape) by inducing alterations in bacteria membranes and the cytoplasm, as visualized by transmission electron microscopy (TEM). The presence of an NLC protein corona, composed of 93% albumin, was confirmed by mass spectrometry. This protein corona delayed the bactericidal activity of anionic NLC against H. pylori and hindered NLC activity against Escherichia coli. Overall, these results sustain the use of NLC as a promising antibiotic-free strategy targeting H. pylori. [ABSTRACT FROM AUTHOR]

Copyright of Rónai - Revista de Estudos Classicos e Tradutorios is the property of Ronai - Revista de Estudos Classicos e Tradutorios and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objective: To describe ocular surface findings in impression cytology obtained from healthy rabbit conjunctiva treated with interferon alpha-2b eyedrop, and compare them to findings after use of mitomycin C 0.02%. Methods: An experimental study using a rabbit model was performed between September 2013 and October 2014 at the Faculdade de Medicina de Marília, Universidade Federal de São Paulo, Clínica de Olhos Moacir Cunha. Thirty New Zealand white rabbits were divided into 6 groups and received interferon alpha-2b or mitomycin C 0.02%. Impression cytology (IC) was performed prior to topical applications and at15, 30 and 60 days of use. The following variables were analyzed in impression cytology: goblet cells, cellularity, cell-to-cell adhesion, nucleus/cytoplasm ratio, nuclear chromatin, inflammatory cells keratinization, and cytomegaly. Results: The major findings in impression cytology after us of interferon alpha-2b included loss of goblet cells (50.8%), reduced cell-to-cell adhesion (26.2%), abnormal nucleus/cytoplasm ratio (20%) and reduced cellularity (15.4%). After use of mitomycin C 0.02%, the most common changes included loss of goblet cells (46.2%), abnormal nucleus/cytoplasm ratio (25.6%), less cell-to-cell adhesion (23.1%), and reduced cellularity (20.5%). There were no significant differences in any variable when comparing impression cytology after interferon alpha-2b and after mitomycin C 0.02%. Goblet cell loss was more pronounced at days 30 and 60, as compared to impression cytology at day 15 for both drugs. Conclusion: The loss of goblet cells, reduced cell-to-cell adhesion and cellularity, along with abnormal nucleus/cytoplasm ratio were the most common findings in impression cytology after use of interferon alpha-2b.These findings are similar to those described for use of mitomycin C 0.02%. .. [ABSTRACT FROM AUTHOR]

The detection of thrombin based on aptamer binding is studied using two different optical fiber-based configurations: long period gratings coated with a thin layer of titanium dioxide and surface plasmon resonance devices in optical fibers coated with a multilayer of gold and titanium dioxide. These structures are functionalized and the performance to detect thrombin in the range 10 to 100 nM is compared in transmission mode. The sensitivity to the surrounding refractive index (RI) of the plasmonic device is higher than 3100 nmRIU-1 in the RI range 1.335 to 1.355, a factor of 20 greater than the sensitivity of the coated grating. The detection of 10 nM of thrombin was accomplished with a wavelength shift of 3.5 nm and a resolution of 0.54 nM. [ABSTRACT FROM AUTHOR]

Copyright of Arquivos Brasileiros de Oftalmologia is the property of Arquivos Brasileiros de Oftalmologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study aims to create awareness, both within the scientific community and among providers of sports facilities, for individuals with impaired or reduced mobility, promoting the development of technical solutions that allow greater autonomy and social integration of people with disabilities. The purpose of this work is, on the one hand, to evaluate the accessibility of sports facilities for people with reduced mobility and, on the other hand, to investigate why this user group has such low rates of participation in sporting activities. Firstly, using the Portuguese norms and legislation transcribed from European Community directives, a check list was created comprising all the items that sports facilities should abide by in order to provide accessibility and safety to people with reduced mobility. Another questionnaire was designed aimed at this user group, with questions pertaining to their desire and ability to use sports facilities. This questionnaire was distributed in Portugal, in the greater metropolitan area of Porto, to users of Rehabilitation Centres and Physiotherapy Clinics. The results obtained from the check-list showed the compliances and non-compliances of the respective sports facilities, proving that many barriers preventing the participation of people with reduced mobility still exist. Twenty-four people with permanent impairment of the lower extremities (paraplegia) answered the questionnaire pertaining to the desire and ability to perform physical activity. Two individuals (8%) had sporting activities available to them in their area of residence and only five (21%) performed any physical activity. The main reason given for not taking part in any activity was the lack of adapted sports facilities. All the participants felt that taking part in sports is beneficial. The benefits stated were: general well-being and development of the psychomotor component (e.g. coordination, balance, body posture), of physical condition (e.g. strength, resistance, flexibility) and social integration and quality of life. Besides wellbeing, they also mentioned social interaction, a way of occupying their time and an escape from the routine as the main motives for which they would like to take up physical exercise. [ABSTRACT FROM AUTHOR]

Copyright of Arquivos Brasileiros de Oftalmologia is the property of Arquivos Brasileiros de Oftalmologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Ophthalmology is the property of Elsevier B.V. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Purpose: To describe a case of eyelid sarcoidosis without systemic manifestations with a three-year follow-up. Methods: A 73-year-old woman presented complaining of a one-year history of swelling and hyperemia in the right upper eyelid. To confirm the diagnosis, we performed an incisional biopsy of the eyelid. Results: Histopathological examination showed a non-caseating granulomatous process suggestive of sarcoidosis. After three years, the patient was asymptomatic and physical and laboratory examination showed no signs of systemic sarcoidosis. Conclusion: The histopathological exam was fundamental for the diagnosis. [ABSTRACT FROM AUTHOR]

Infections and thrombus formation are major concerns for the success of blood‐contacting medical devices. Antimicrobial coatings based on antimicrobial peptides (AMPs) are described as promising strategies to fight biomaterial‐associated infections. However, their efficiency in the presence of plasma and their effect on platelets adhesion/activation, essential for blood contact applications, is not known. In this work, the AMP cecropin–melittin (CM) is covalently immobilized onto polyurethane (PU) films envisaging a coating for intravascular catheters. Immobilization is done by dip‐coating of a layer of gold nanoparticles (Au NPs) functionalized with NH2 and COOH terminated polyethylene glycol (PEG). Surfaces characterized using scanning electron microscopy (SEM), X‐ray photoelectron spectroscopy (XPS), quartz crystal microbalance with dissipation (QCM‐D), and colorimetric assays reveal a stable and homogeneous coating distribution. CM coating significantly reduces Staphylococcus epidermidis adhesion to PU films (≈80% in PBS). Its bactericidal activity is not affected in the presence of 1% human plasma (hPlasma) proteins with 65% reduction on viable bacteria comparing to PU. Moreover, CM coating is able to prevent platelet adhesion/activation to PU films (≈95% in PBS). This effect is also observed when surfaces are precoated with hPlasma. Overall, the developed antimicrobial coating demonstrates great potential to prevent bacterial infections on PU devices without instigating platelet adhesion/activation. In this work, a coating based on cecropin–melittin antimicrobial peptide is engineered for prospective applications in polyurethane catheters. The coating prevents Staphylococcus epidermidis adhesion, displaying as well bactericidal features. It is also effective against platelets adhesion and activation. Overall, the engineered coating shows excellent antibacterial activity and promising antithrombogenic properties. [ABSTRACT FROM AUTHOR]

Purpose: To determine Toxoplasma gondii genotype in scars of retinochoroiditis in humans. Design: Immunopathology analysis. Methods: DNA was isolated from retinochoroidal specimens taken from the borders of the scars from eye bank eyes as well as enucleated eyes from uveitis patients with retinochoroidal toxoplasmic scars. The SAG2 region was amplified by polymerase chain reaction and analyzed by restriction fragment length polymorphism. Results: Of the 92 eyes studied, 9 had toxoplasmic scars. All of them, as well as the 2 enucleated eyes, disclosed the presence of type I parasites by the gel electrophoresis analysis of the restriction fragment length polymorphism from SAG2. Conclusion: These results suggest that type I strain seems to be responsible for the ocular infections in the population studied. [Copyright &y& Elsevier]

Abstract: Purpose: Ocular lesions are frequent in various individuals infected with Toxoplasma gondii. Disease intensity in ocular toxoplasmosis varies greatly between patients. Autoimmunity has been suggested as a possible component to retinal destruction. Methods: Immunologic parameters in the response to retina antigens were evaluated in infected persons with and without ocular lesions and in non-infected controls. Subjects were divided into groups on the basis of titers of serum antibodies to T. gondii, presence and severity of ocular lesions, and clinical history. Results: Peripheral blood mononuclear cells from patients with mild disease responded to one or more retinal antigens with a significantly higher frequency than patients without disease or with severe disease. Interestingly, the cytokines produced by the proliferating mononuclear cells did not follow any specific patterns, except for the fact that IL-4 and IL-5 were seldom detected. Conclusions: Our results suggest that although the presence of an immune response towards autoantigens is not protective against the development of ocular lesions by the T. gondii, it may protect against the development of severe disease. [Copyright &y& Elsevier]