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In chronic wound (CW) scenarios, Staphylococcus aureus-induced infections are very prevalent. This leads to abnormal inflammatory processes, in which proteolytic enzymes, such as human neutrophil elastase (HNE), become highly expressed. Alanine-Alanine-Proline-Valine (AAPV) is an antimicrobial tetrapeptide capable of suppressing the HNE activity, restoring its expression to standard rates. Here, we proposed the incorporation of the peptide AAPV within an innovative co-axial drug delivery system, in which the peptide liberation was controlled by N-carboxymethyl chitosan (NCMC) solubilization, a pH-sensitive antimicrobial polymer effective against Staphylococcus aureus. The microfibers' core was composed of polycaprolactone (PCL), a mechanically resilient polymer, and AAPV, while the shell was made of the highly hydrated and absorbent sodium alginate (SA) and NCMC, responsive to neutral-basic pH (characteristic of CW). NCMC was loaded at twice its minimum bactericidal concentration (6.144 mg/mL) against S. aureus, while AAPV was loaded at its maximum inhibitory concentration against HNE (50 μg/mL), and the production of fibers with a core-shell structure, in which all components could be detected (directly or indirectly), was confirmed. Core-shell fibers were characterized as flexible and mechanically resilient, and structurally stable after 28-days of immersion in physiological-like environments. Time-kill kinetics evaluations revealed the effective action of NCMC against S. aureus, while elastase inhibitory activity examinations proved the ability of AAPV to reduce HNE levels. Cell biology testing confirmed the safety of the engineered fiber system for human tissue contact, with fibroblast-like cells and human keratinocytes maintaining their morphology while in contact with the produced fibers. Data confirmed the engineered drug delivery platform as potentially effective for applications in CW care., Authors acknowledge the Portuguese Foundation for Science and Technology (FCT), FEDER funds by means of Portugal 2020 Competitive Factors Operational Program (POCI) and the Portuguese Government (OE) for funding the project PEPTEX with reference PTDC/CTMTEX/28074/2017 (POCI-01-0145-FEDER-028074). Authors also acknowledge project UIDP/00264/2020 of 2C2T and UID/QUI/00686/2020 of CQ, funded by national funds through FCT/MCTES. C.S.M. and H.P.F. also acknowledge FCT for PhD funding via scholarship 2020.08547.BD and for auxiliary researcher contract via 2021.02720.CEEIND, respectively.

[Excerpt] In the last couple of years, the awareness of climate change and high pollution levels have raised our sense of ecological responsibility. Pharmaceutical industries play a major role in these issues; as such, alternatives must be found. New environmentally friendly approaches to deal with the growing concern associated with antimicrobial-resistant bacteria are also in great demand. The excessive consumption and misuse of these agents have accelerated the rise of such pathogens responsible for compromising global health—not only the health of humans, but also the health of all living systems., This research was funded by the Portuguese Foundation for Science and Technology (FCT) via grant UID/CTM/00264/2020 of 2C2T Strategic Project 2020–2023. H.P.F. also acknowledges the FCT for Auxiliary Researcher contract 2021.02720.CEECIND.

The potential of nanoparticles as effective drug delivery systems combined with the versatility of fibers has led to the development of new and improved strategies to help in the diagnosis and treatment of diseases. Nanoparticles have extraordinary characteristics that are helpful in several applications, including wound dressings, microbial balance approaches, tissue regeneration, and cancer treatment. Owing to their large surface area, tailor-ability, and persistent diameter, fibers are also used for wound dressings, tissue engineering, controlled drug delivery, and protective clothing. The combination of nanoparticles with fibers has the power to generate delivery systems that have enhanced performance over the individual architectures. This review aims at illustrating the main possibilities and trends of fibers functionalized with nanoparticles, focusing on inorganic and organic nanoparticles and polymer-based fibers. Emphasis on the recent progress in the fabrication procedures of several types of nanoparticles and in the description of the most used polymers to produce fibers has been undertaken, along with the bioactivity of such alliances in several biomedical applications. To finish, future perspectives of nanoparticles incorporated within polymer-based fibers for clinical use are presented and discussed, thus showcasing relevant paths to follow for enhanced success in the field., This research was funded by the Portuguese Foundation for Science and Technology (FCT) via grants UIDP/00264/2020 of 2C2T Strategic Project 2020–2023 and project PTDC/CTMTEX/28074/2017. This project has been funded by a Research Grant (2022) from the European Society of Clinical Microbiology and Infectious Diseases (ESCMID) to J.C.A., J.M.D. and C.S.M. also acknowledge FCT for PhD grants 2020.07387.BD and 2020.08547.BD, respectively, and H.P.F. for auxiliary researcher contract 2021.02720.CEECIND.

The purpose of this research was to analyze the morphology, thermal and mechanical properties of poly(vinyl alcohol) (PVA)-based electrospun mats reinforced with cellulose acetate (CA) or cellulose nanocrystalline (CNC) for potential applications in wound dressings. Bead-free and water-stable electrospun nanofibers made of blends of PVA and CA or CNC were successfully produced and crosslinked with glutaraldehyde vapor. Crosslinking slightly increased the nanofibers’ diameters in order of 43 and 13% for 80/20 PVA/CA and PVA/CNC electrospun mats, respectively, while maintaining their bead-free morphology. Thermogravimetry (TGA) and differential scanning calorimetry (DSC) evaluations were employed to determine the miscibility and the thermal response of the uncrosslinked and crosslinked mats, reporting a reduction in mass loss upon addition of CA and CNC and upon crosslinking process. Polymers’ powder and mats (before and after crosslinking) crystallinity was assessed by X-ray diffraction analysis (XRD). Crosslinked mats experienced a slight reduction in crystallinity compared to the uncrosslinked. Static and dynamic tensile strength tests revealed that CA and CNC doped mats enhanced the Young's modulus and lowered deformation at failure compared to pristine PVA electrospun mats. Data from storage modulus (E’) demonstrated the strength of the physical interactions formed between PVA and the cellulosic derivatives (either before and after crosslinking), highlighting the stiffness of CA (231.58 MPa for the 80/20 mat) and, particularly, CNC (742.04 MPa for the 80/20 mat). This research uncovered important information concerning the chemical and physical relation between polymeric matrices and additives, essential for the proper selection of materials for wound dressings production., Authors acknowledge the Portuguese Foundation for Science and Technology (FCT), FEDER funds by means of Portugal 2020 Competitive Factors Operational Program (POCI) and the Portuguese Government (OE) for funding the project with reference PTDC/CTM-TEX/28074/2017 (POCI-01-0145-FEDER-028074). Authors also acknowledge project UIDP/00264/2020 of Centre for Textile Science and Technology (2C2T), funded by national funds through FCT/MCTES. M.A.T., D.P.F and H.P.F. also acknowledge FCT for PhD scholarship (SFRH/BD/148930/2019) and junior (CEECIND/02803/2017) and auxiliary researcher (2021.02720.CEECIND) contracts, respectively.

[Excerpt] The antibiotic crisis is a global concern. The increasing rates of microbial resistance to antibiotics have led researchers to question their efficiency and to invest their efforts into other molecules, particularly those of natural origin. Indeed, Chittasupho et al. examined the combined effects of quercetin and curcuminoid extracts on the antimicrobial, antioxidant, and cell migration activities, and overall wound healing properties, and assessed their potential for applications in wound therapies., This research was funded by the Portuguese Foundation for Science and Technology (FCT) via grant UIDP/00264/2020 of 2C2T Strategic Project 2020-2023. H.P.F. also acknowledges FCT for Auxiliary Researcher contract 2021.02720.CEECIND.

Diabetic foot ulcers (DFUs) are one of the main complications of diabetes and are characterized by their complexity and severity, which are frequently aggravated by overexpressed inflammatory factors and polymicrobial infections. Most dressing systems offer a passive action in the treatment of DFUs, being frequently combined with antibiotic or immunomodulatory therapies. However, in many instances due to these combined therapiesʹ inability to properly fight microbial presence, and provide a suitable, breathable and moist environment that is also capable of protecting the site from secondary microbial invasions or further harm, aggravation of the wound state is unavoidable and lower limb amputations are necessary. Considering these limitations and knowing of the urgent demand for new and more effective therapeutic systems for DFU care that will guarantee the quality of life for patients, research in this field has boomed in the last few years. In this review, the emerging innovations in DFU dressing systems via fiber‐based scaffolds modified with bioactive compounds have been compiled; data focused on the innovations introduced in the last five years (2017–2022). A generalized overview of the classifications and constraints associated with DFUs healing and the bioactive agents, both antimicrobial and immunomodulatory, that can contribute actively to surpass such issues, has also been provided., This research was funded by the Portuguese Foundation for Science and Technology (FCT) via grant UIDP/00264/2020 of 2C2T Strategic Project 2020–2023. H.P.F. also acknowledges FCT for contract 2021.02720.CEECIND

[Excerpt] For many years, antibiotics have been the most widely used antimicrobial agents to fight infections. However, their excessive consumption has led to an alarmingly high development of resistance by microbial pathogens, raising a serious global, public-health problem (Felgueiras 2021, Lewies et al. 2019, Rončević et al. 2019). Hence, the growing search for alternatives to these agents. In recent years, antimicrobial peptides (AMPs) have been the focus of great interest since they are the most widespread and evolutionarily conserved components of the innate immune system, acting as a primary line of host defense against microbial infections (Magana et al. 2020).

[Excerpt] Introduction Wound infection is a critical factor that seriously hinders adequate healing preventing epithelialization and angiogenesis. This is particularly grievous and prevalent in burn and chronic wounds., This research was funded by FEDER funds through the Operational Competitiveness Program–COMPETE under the Project POCI-01-0247-FEDER-039733, and by National Funds through Fundação para a Ciência e Tecnologia (FCT), under the project UID/CTM/00264/2020. Liliana Melro, Rui D. V. Fernandes, and Ana Isabel Ribeiro acknowledge FCT, MCTES, FSE, and UE PhD grants 2020.04919.BD, SFRH/BD/145269/2019, SFRH/BD/137668/2018.

[Excerpt] Infectious diseases are a perpetual challenge as they are one of the main human health issues (Irshad et al. 2020). Several pathogens such as viruses, bacteria, fungi and parasites are behind these diseases, which are accountable for 10% of the global mortality annually. Recently, the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) gave rise to a novel coronavirus disease, COVID-19, and triggered a pandemic situation which already caused more than 5 million deaths worldwide (WHO 2021). Among the causing agents of infectious diseases, bacteria are considered one of the most concerning classes of pathogens.

O objetivo deste artigo é abordar a experiência da Comissão da Sustentabilidade em elaborar, discutir e implementar diretrizes que promovessem ações mais sustentáveis nas etapas de preparação, execução e pós-realização do evento I Simpósio Nacional de Gestão e Engenharia Urbana, realizado entre os dias 25 e 27 de outubro de 2017, na Universidade Federal de São Carlos. Essa comissão desenvolveu diversas diretrizes em conjunto com as demais comissões para evitar e minimizar impactos ambientais negativos e estabelecer critérios de consumo de materiais e energia. Foram realizadas observações das ações adotadas pelas comissões e estabelecidos instrumentos de coleta de dados que viabilizassem o cálculo da Pegada Carbônica do evento. Nas ações vinculadas a mudanças comportamentais, tanto dos membros das comissões organizadoras quanto dos participantes do evento, obtiveram-se resultados satisfatórios. Entretanto, houve dificuldades nas ações dependentes de modificações da infraestrutura existente no campus.

In the past few years, the outstanding properties of the best-known derivative of graphene, the graphene oxide (GO), have led to a wide increase of its spectra of application. GO-based composites have been reported as chemically and mechanically stable, presenting good biocompatibility and great antimicrobial potential. Also, GO's two-dimensional planar structure coupled with its large availability of oxygen-related functional groups can turn this material into a good candidate for several biomedical devices, including wound dressings (WD) and drug delivery systems (DDS). In this scenario, the present review compiles the most advanced and innovative research in WD and DDS containing GO, conducted in last 10 years. An overview of GO's global and specific biomedical properties was presented, alongside with a description of the current GO and GO-based composites producing methods for biomedical applications. In addition, the future challenges, and perspectives of the application of GO for WD and DDS were briefly analysed., FCT -Fundação para a Ciência e a Tecnologia(2C2T)

Human-induced transformations lead to multiple threats to biodiversity in freshwater ecosystems mainly related to climate change, biological invasion, land use change, pollution, and overexploitation. These threats operate through multiple mechanisms, which can be complementary or compensatory. However, the effects of the major threats to biodiversity across ecological scales are still unclear, as well as its operating mechanisms. We performed a meta-analysis on their impacts on freshwater ecosystems to assess their general and relative importance across multiple ecological levels. We demonstrated that pollution was consistently the most important threat to freshwater ecosystems change, but the relative importance of each threat depended on the ecological level. At the population level, nutrient loading driven by pollution and climatic warming had higher relative importance, increasing metabolic rates through a bottom-up effect. However, this effect did not propagate to other ecological scales. Communities were more sensitive to the impacts of biological invasion and land use change, both synergically decreasing their diversity, evenness, and richness. At the ecosystem level, both pollution and land use change impacts were more relevant to eutrophication of freshwater ecosystems. We highlight the lack of information on impacts from overexploitation and studies demonstrating the combined effect among these major threats. We concluded that freshwater ecosystems are prone to these threats by a set of pathways in which their impacts are not equally widespread across the ecological levels, affecting them in a multidirectional way. We reinforce the importance of designing conservation strategies that allow counteracting the impacts of biodiversity loss by multiple pathways and including such multidirectionality to plan global actions to protect freshwater ecosystems.

Burn wounds can lead to numerous severe complications including bacterial infections causing patient morbidity and mortality, mostly in low- and middle-income countries. The Grampositive bacteria Staphylococcus aureus is one of the major causes of nosocomial infections in burn patients. Furthermore, the considerable increase of the microbial resistance against traditional antibiotics is leading towards alternative strategies to treat bacterial infections. Nisin Z is an antimicrobial peptide which exhibits a significant antibacterial activity against Gram-positive bacteria. The incorporation of peptide and other biomolecules within a biopolymer matrix provides protection maintaining their antimicrobial potential. Bacterial nanocellulose (BNC) has been widely used as wound dressings. Its impressive water retention capacity (>99%) and porosity are beneficial to manage wounds due to its potential to absorb exudates, providing a breathable and humid environment. In this work, the functionalization of BNC with nisin Z (BNC-NZ) via vacuum filtration is reported. The entrapment of the peptide inside the BNC films was confirmed through morphological characterization using Attenuated Total Reflectance-Fourier Transform Infrared (ATR-FTIR) spectrometry. Typical absorbance peaks of nisin Z are easily identifiable at 1647 cm−1 (amide group) and 1520 cm-1 (bending of primary amines). Thermal Gravimetric Analysis (TGA) suggested that nisin Z did not interfere with the BNC matrix. The antimicrobial activity of nisin Z against S. aureus strains including a multiple drug-resistant, was verified by Minimum Bactericidal Concentration (MBC). Agar Diffusion and Shake Flask methods revealed the potential of BNC-NZ for prospective applications in burn wound dressings.

A skin wound if not properly treated can result in a chronic wound susceptible to widespread infections, which can result in the patient's death. Currently, tissue engineering is described as an interdisciplinary field that combines principles of engineering, chemistry and biology to generate solutions that allow to repair, restore and/or improve the functions of injured tissues. In the same sense, the textile area addresses solutions based on polymeric fibers, produced from a wide range of polymers, which allow the generation of structures with a large surface area, porosity and mechanical resistance that can be used as bioactive dressings that promote a healing and efficient antimicrobial activity. This research work focused on the synthesis of Tiger 17, through microwave-assisted solid-phase synthesis methodologies, and Tiger 17 commercially obtained, respective structural characterization and evaluation of the antimicrobial capacity. Simultaneously, nanofibrous polymer matrices were produced using the electrospinning technique with the aim of immobilizing the developed biomolecule and thus creating potential vehicles for a local and sustainable antimicrobial action (controlled release). In order to verify its physical and chemical properties, advanced characterization techniques were used: proton nuclear magnetic resonance, high performance liquid chromatography, optical microscopy, scanning electron microscopy, fourier transform infrared spectroscopy–attenuated total reflectance, thermogravimetry, differential scanning calorimetry, contact angle and surface energy and determination of porosity and hydration., Düzgün tedavi edilmeyen bir cilt yarası, hastanın ölümüyle sonuçlanabilecek yaygın enfeksiyonlara duyarlı kronik bir yaraya neden olabilir. Günümüzde doku mühendisliği, hasarlı dokuların işlevlerini onarmaya, eski haline getirmeye ve/veya iyileştirmeye olanak tanıyan çözümler üretmek için mühendislik, kimya ve biyolojinin ilkelerini birleştiren disiplinler arası bir alan olarak tanımlanmaktadır. Bu kapsamda, tekstil, iyileşmeyi ve etkili antimikrobiyal aktiviteyi teşvik eden biyoaktif pansuman olarak kullanılabilecek, geniş yüzey alanlı, gözenekli ve mekanik dirençli yapıların oluşturulmasına izin veren, geniş bir polimer yelpazesinden üretilen liflere dayalı çözümler sunmaktadır. Bu araştırma çalışması, mikrodalga destekli katı faz sentez metodolojileri aracılığıyla Tiger 17'nin sentezine ve ticari olarak temin edilen Tiger 17 ile birlikte yapısal karakterizasyonunun ve antimikrobiyal kapasitenin değerlendirilmesine odaklanmıştır. Aynı zamanda, geliştirilen biyomolekülü hareketsiz hale getirmek ve böylece lokal ve sürdürülebilir bir antimikrobiyal etki (kontrollü salım) için potansiyel çözümler yaratmak amacıyla elektrik alan lif üretim tekniği kullanılarak nanolifli polimer matrisler üretildi. Yapının fiziksel ve kimyasal özelliklerini doğrulamak için, proton nükleer manyetik rezonans, yüksek performanslı sıvı kromatografisi, optik mikroskopi, taramalı elektron mikroskobu, fourier dönüşümü kızılötesi spektroskopisi-zayıflatılmış toplam yansıma, termogravimetri, diferansiyel taramalı kalorimetri, temas açısı, yüzey enerjisi, gözeneklilik ve su tutma ölçümleri gibi ileri karakterizasyon teknikleri kullanıldı, (undefined)

[Excerpt] Biomaterials can be used as implantable devices or drug delivery platforms, which have significant impacts on the patient’s quality of life. Indeed, every year, a substantial number of new biomaterials and scaffolding systems are engineered and introduced in the biomedical field, with increased health benefits observed, as reported by Spalek et al. [1]. However, their long-term use can be threatened by the adhesion and proliferation of microorganisms, which can interact and form biofilms, or by the formation of fibrosis and consequent triggered cytotoxic responses. Pathogenic microorganisms may cause local infections and lead to implant failures., This research was funded by the Portuguese Foundation for Science and Technology (FCT) via grants PTDC/CTMTEX/28074/2017 and UID/CTM/00264/2021.

In this research, we propose to engineer a nanostructured mat that can simultaneously kill bacteria and promote an environment conducive to healing for prospective wound care. Polyvinyl alcohol (PVA) and cellulose acetate (CA) were combined at different polymer ratios (100/0, 90/10, 80/20% v/v), electrospun and crosslinked with glutaraldehyde vapor. Crosslinked fibers increased in diameter (from 194 to 278 nm), retaining their uniform structure. Fourier-transform infrared spectroscopy and thermal analyses proved the excellent miscibility between polymers. CA incorporation incremented the fibers swelling capacity and reduced the water vapor and air permeabilities of the mats, preventing the excessive drying of wounds. The antimicrobial peptide cys-pexiganan and the immunoregulatory peptide Tiger 17 were incorporated onto the mats via polyethylene glycol spacer (hydroxyl-PEG2-maleimide) and physisorbed, respectively. Time-kill kinetics evaluations revealed the mats effectiveness against Staphylococcus aureus and Pseudomonas aeruginosa. Tiger 17 played a major role in accelerating clotting of re-calcified plasma. Data reports for the first time the collaborative effect of pexiganan and Tiger 17 against bacterial infections and in boosting hemostasis. Cytocompatibility data verified the peptide-modified mats safety. Croslinked 90/10 PVA/CA mats were deemed the most promising combination due to their moderate hydrophilicity and permeabilities, swelling capacity, and high yields of peptide loading., This research received funding from the Portuguese Foundation for Science and Technology (FCT) under the scope of the projects PTDC/CTM-TEX/28074/2017 (POCI-01-0145-FEDER-028074), PTDC/NANMAT/31444/2017 (POCI-01-0145-FEDER-031444), UID/CTM/00264/2020, UIDB/50006/2020 and SFRH/BD/148930/2019., Authors acknowledge the Portuguese Foundation for Science and Technology (FCT), FEDER funds by means of Portugal 2020 Competitive Factors Operational Program (POCI) and the Portuguese Government (OE) for funding the projects with reference PTDC/CTM-TEX/28074/2017 (POCI-01-0145-FEDER-028074) and PTDC/NANMAT/31444/2017 (POCI-01-0145-FEDER-031444). Authors also acknowledge project UID/CTM/00264/2020 of Centre for Textile Science and Technology (2C2T), funded by national funds through FCT/MCTES. M.A.T. acknowledges FCT for the PhD grant with reference SFRH/BD/148930/2019. The authors acknowledge to the institution LAQV – Laboratório Associado para a Química Verde (UIDB/50006/2020).