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Copyright of Revista Maracanan is the property of Revista Maracanan 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.)

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]

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]

The article studies the experience of Jesuit missionaries who worked in the "Austral Missions" (1750-1753) in the current territory of the Province of Buenos Aires. The sources that support the research are letters and reports from Jesuits and members of the colonial government, referring to the foundation, functioning and abandonment of that "pueblos de indios". It will be critically analyzed seeking to understand the effects of this experience on the subjectivity of religious people. Therefore, in addition to working with sources, we will also make use of comparisons with situations of a similar nature, in other mission areas, as well as the debate with historiography. [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]

Copyright of Romanitas: Revista de Estudos Greco-Latinas is the property of Universidade Federal do Espirito Santo 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 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.)

The article evaluates the history of Latin American countries during the last 30 years, with specific reference to the Postgraduate Program in History of the University of Vale do Rio dos Sinos. Topics discussed include Latin America's place in Brazilian history; political inflections and academic policies in Latin America; and how the reunification of Germany and the dissolution of the Soviet Union influenced Latin America; and the abandonment of political positions towards historiographical productions carried out by foreign national researchers.

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]

An interview with Raúl J. Mandrini, professor at the Instituto de Estudios Histórico-Sociales de la Universidad Nacional del Centro de La Provincia de Buenos Aires (UNICEN) is presented. He presented his views on various topics including his professional career, his interest in ancient history, research conducted by historians on indigenous peoples, Indian history, the relation between research of anthropology and archeology, indigenous knowledge and contemporary historiography.

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.)

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]