452 research outputs found
Co-delivery of two anti-HIV drug nanocrystals from electrospun nanofibers
TRUVADA is the only medication approved by FDA for pre-exposure prophylaxis of the HIV infection.
They are tablets with fixed dosages of two antiretroviral compounds for daily oral uptake: Tenofovir disoproxil fumarate (TDF) and Emtricitabine (EMT) that are reverse transcriptase inhibitors.
Objectives: Incorporate TDF and EMT drugs in polymeric nanofibers produced by electrospinning; chosen polymers were polyoxyethilene (PEO) and polycaprolactone (PCL). Characterize the nanofibers and study the in vitro release profile of the drugs. Evaluate the possibility of a topical administration of the loaded fibers , by rectal or genital route, for HIV infection prophylaxis.: We thank PARALAB for the SEM analysis and Dr. A. S. Azevedo for the X-ray analysis. This work was supported
by the Portuguese Foundation for Science and Technology (FCT) in the framework of the Strategic Funding UID/FIS/04650/2013, and
Programa Gilead GĂNESE, Portugal (ref. PGG/046/2015). Marlene LĂșcio acknowledges the exploratory project funded by FCT with the
reference IF/00498/2012. José das Neves acknowledges FCT for financial support (grant SFRH/BPD/92934/2013).info:eu-repo/semantics/publishedVersio
MP-Collaborator: a mobile collaboration tool in pervasive environment
âCopyright © [2009] IEEE. Reprinted from 5th International Conference on Wireless and Mobile Computing, Networking and Communications. WIMOB 2009. ISBN: 978-0-7695-3841-9
. This material is posted here with permission of the IEEE. Internal or personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution must be obtained from the IEEE by writing to [email protected]. By choosing to view this document, you agree to all provisions of the copyright laws protecting it.âIn modern organizations, the communication between collaborators is essential to improve productivity. There is a need for mobile collaboration tools that allow efficient collaboration among staff in organization which may be located in different geographical areas and time zones. Mobile and pervasive computing provides easy and convenient access to information, enabling effective collaboration. This paper describes a context and location-aware mobile application, called MP-Collaborator, created to improve and optimize the communication between collaborators in any organization. MP- Collaborator draws information from location, user status and Pocket Outlook Calendar to create a user availability profile, which is published to any other user in the network. Based on availability status, the user can be reached using a simple phone call or a message. Through the opportunistic use of available mobile technologies MP-Collaborator provides a simple but critical service - user presence service. The proposed solution is validated both in terms of features and communication through a series of experiments on real devices through Wi-Fi network
Release of acyclovir from polymeric nanofibers: comparing aqueous versus membrane-water interfaces kinetics
We are very thankful to Labesfal Genericos, S.A. for kindly providing acyclovir. We also thank PARALAB for the SEM-EDS analysis and Sr. Azevedo for the X-ray analysis. This work was supported by the Portuguese Foundation for
Science and Technology (FCT) in the framework of the Strategic Funding UID/FIS/04650/2013. Marlene LĂșcio acknowledges the exploratory project funded by FCT with the reference IF/00498/2012The objective of this study is to develop a novel system for acyclovir (ACV) controlled release after cutaneous application through the encapsulation of the drug into polymeric nanofibers of policaprolactone (PCL) produced by the electrospinning technique to overcome the limitations of the conventional topical
formulations.info:eu-repo/semantics/publishedVersio
TDF/FTC electrospun nanofibers for topical prevention of HIV transmission
Human immunodeficiency virus (HIV) is still a problem for global health so, there is a strong need to develop effective microbicides that can be used safely to protect from infection during sexual intercourse. This pre-exposure prophylaxis (PrEP) may be formulations containing oral or topical microbicides. Topical formulations have advantages as they are suitable for vaginal or rectal application and allow a higher local concentration of drug. It is recognized that the use of electrospun nanofibers for drug carriers is very promising in the biomedical field. So, the objective of this study is to develop a novel device for local application of antiretroviral microbicides enabling a controlled release of tenofovir disoproxil fumarate (TDF) and emtricitabine (FTC), based on electrospun polymeric nanofibers. The aim of this study is to encapsulate TDF and FTC into electrospun polymeric nanofibers. Chosen polymers were polycaprolactone (PCL) and poly(vinyl alcohol) (PVA).info:eu-repo/semantics/submittedVersio
Valorization of chicken feathers using aqueous solutions of ionic liquids
The poultry-processing industry generates large quantities of waste rich in keratin, a fibrous protein representing around 90 wt % of chicken feathers, which is currently disposed of in landfilling or incinerated. Keratin is commonly recognized as a renewable biopolymer resource used for biomaterials preparation (e.g., films and hydrogels) with interest for biomedical applications. Even though research on keratin recovery from chicken feathers started many years ago, very few keratin materials from this source have been developed due to the low keratin solubility in most common solvents and poor protein recovery yield. Although ionic liquids (ILs) have been reported as alternative solvents with high dissolution capability for several biopolymers, keratin recovery from chicken feathers using aqueous solutions of ILs was not investigated up to date. Considering the Green Chemistry Principles (especially the first one: zero waste) and Circular Economy concepts, in this work, we show that chicken feathers can be effectively dissolved in an aqueous solution of 1-butyl-3-methylimidazolium acetate (80 wt %), further allowing the keratin recovery and preparation of keratin biofilms. The keratin recovery from the IL aqueous solution was optimized considering the coagulant type, solution:coagulant weight ratio, temperature, and time, being the coagulant type the variable with higher influence in the recovery process. Under the best conditions (ethanol, 1:2 w/w, 5 °C, and 1 h), 90 wt % of keratin was recovered. The IL recovery and reuse were also evaluated, still allowing 82 wt % of recovery yield at the end of the third cycle. The recovered keratin was characterized, confirming the required physicochemical properties. A keratin film was finally prepared and characterized through cell viability, oxidative stress and wound healing assays, opening the path for the use of keratin films in biomedical applications.publishe
Multi-Omic profiling of macrophages treated with phospholipids containing Omega-3 and Omega-6 fatty acids reveals complex immunomodulatory adaptations at protein, lipid and metabolic levels
In recent years, several studies have demonstrated that polyunsaturated fatty acids have strong immunomodulatory properties, altering several functions of macrophages. In the present work, we sought to provide a multi-omic approach combining the analysis of the lipidome, the proteome, and the metabolome of RAW 264.7 macrophages supplemented with phospholipids containing omega-3 (PC 18:0/22:6; omega 3-PC) or omega-6 (PC 18:0/20:4; omega 6-PC) fatty acids, alone and in the presence of lipopolysaccharide (LPS). Supplementation of macrophages with omega 3 and omega 6 phospholipids plus LPS produced a significant reprogramming of the proteome of macrophages and amplified the immune response; it also promoted the expression of anti-inflammatory proteins (e.g., pleckstrin). Supplementation with the omega 3-PC and omega 6-PC induced significant changes in the lipidome, with a marked increase in lipid species linked to the inflammatory response, attributed to several pro-inflammatory signalling pathways (e.g., LPCs) but also to the pro-resolving effect of inflammation (e.g., PIs). Finally, the metabolomic analysis demonstrated that supplementation with omega 3-PC and omega 6-PC induced the expression of several metabolites with a pronounced inflammatory and anti-inflammatory effect (e.g., succinate). Overall, our data show that supplementation of macrophages with omega 3-PC and omega 6-PC effectively modulates the lipidome, proteome, and metabolome of these immune cells, affecting several metabolic pathways involved in the immune response that are triggered by inflammation.info:eu-repo/semantics/publishedVersio
Structural features and pro-inflammatory effects of water-soluble organic matter in inhalable fine urban air particles
The impact of inhalable fine particulate matter (PM2.5, aerodynamic diameter < 2.5 ”m) on public health is of great concern worldwide. Knowledge on their harmful effects are mainly due to studies carried out with whole air particles, being the contribution of their different fractions largely unknown. Herein, a set of urban PM2.5 samples were collected during day and nighttime periods in Autumn and Spring, aiming to address the seasonal and day-night variability of water-soluble organic matter (WSOM) composition. In vitro analysis of oxidative and pro-inflammatory potential of WSOM samples was carried out in both acute (24 h) and chronic (3 weeks) exposure setups using Raw264.7 macrophages as cell model. Findings revealed that the structural composition of WSOM samples differs between seasons and in a day-night cycle. Cells exposure resulted in an increase in the transcription of the cytoprotective Hmox1 and pro-inflammatory genes Il1b and Nos2, leading to a moderate pro-inflammatory status. These macrophages showed an impaired capacity to subsequently respond to a strong pro-inflammatory stimulus such as bacterial lipopolysaccharide, which may implicate a compromised capacity to manage harmful pathogens. Further investigation on aerosol WSOM could help to constrain the mechanisms of WSOM-induced respiratory diseases and contribute to PM2.5 regulations.publishe
Control release of acyclovir nanocristals from electrospun nanofibers: comparison of two polymeric matrices
The objective of this study is to develop a novel system for cutaneous application of ACV that is capable of a controlled release of the drug overcoming the limitations of the conventional topical formulations.We are thankful to Labesfal Genericos, S.A. for kindly providing acyclovir. We also thank PARALAB for the SEM-EDS analysis and Dr. A. S. Azevedo for the X-ray analysis. This work was supported by
the Portuguese Foundation for Science and Technology (FCT) in the framework of the Strategic Funding UID/FIS/04650/2013. Marlene LĂșcio acknowledges the exploratory project funded by FCT with the reference IF/00498/2012.info:eu-repo/semantics/publishedVersio
tackling malaria
Malaria is an infectious disease that affects over 216 million people worldwide, killing over 445,000 patients annually. Due to the constant emergence of parasitic resistance to the current antimalarial drugs, the discovery of new drug candidates is a major global health priority. Aiming to make the drug discovery processes faster and less expensive, we developed binary and continuous Quantitative Structure-Activity Relationships (QSAR) models implementing deep learning for predicting antiplasmodial activity and cytotoxicity of untested compounds. Then, we applied the best models for a virtual screening of a large database of chemical compounds. The top computational predictions were evaluated experimentally against asexual blood stages of both sensitive and multi-drug-resistant Plasmodium falciparum strains. Among them, two compounds, LabMol-149 and LabMol-152, showed potent antiplasmodial activity at low nanomolar concentrations (EC50 <500 nM) and low cytotoxicity in mammalian cells. Therefore, the computational approach employing deep learning developed here allowed us to discover two new families of potential next generation antimalarial agents, which are in compliance with the guidelines and criteria for antimalarial target candidates.publishersversionpublishe
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