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1.
Kidney Int Rep ; 9(5): 1397-1405, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38707827

RESUMO

Introduction: Intravitreal administration of vascular endothelial growth factor inhibitors (anti-VEGF) is the treatment of choice in retinal pathology associated with type 2 diabetes mellitus (DM2). We aimed to analyze the effect of intravitreal anti-VEGF administration on renal function in patients with DM2. Methods: This is a single-center retrospective and observational study of patients with DM2 with and without chronic kidney disease (CKD). We analyzed the evolution of renal function after anti-VEGF onset, compared with a control group. Results: We included 45 patients (55.6% male) who received anti-VEGF therapy. Mean age was 74.4±11.5 (50-91) years. These were compared with 45 patients with similar characteristics. After 12 months, 76.3% had CKD with a mean reduction in estimated glomerular filtration rate (eGFR) of 19.4%. Nine patients (20%) had a >25% reduction in eGFR, and 3 patients (6.7%) had a >50% reduction in GFR. At 24 months, 80% of patients had CKD with a mean eGFR decrease of 28%. The mean eGFR slope of patients who had received anti-VEGF treatment was 10 ml/min/year compared to 1.5 ml/min/year in the control group (P < 0.05). After the first administration, 5 patients (17.2%) in the CKD group required renal replacement therapy during follow-up (mean time 22±12 months). Main risk factors for need of dialysis were age, presence of previous CKD, and baseline proteinuria. Conclusion: Intravitreal anti-VEGF administration is a risk factor for CKD and rapid progression to end-stage kidney disease in patients with previous CKD. Knowing these drugs' implications is crucial to avoid CKD progression and opportunely limit their use in certain patients.

2.
Front Bioeng Biotechnol ; 12: 1363865, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38650751

RESUMO

Developing in vitro models that accurately mimic the microenvironment of biological structures or processes holds substantial promise for gaining insights into specific biological functions. In the field of tissue engineering and regenerative medicine, in vitro models able to capture the precise structural, topographical, and functional complexity of living tissues, prove to be valuable tools for comprehending disease mechanisms, assessing drug responses, and serving as alternatives or complements to animal testing. The choice of the right biomaterial and fabrication technique for the development of these in vitro models plays an important role in their functionality. In this sense, elastin-like recombinamers (ELRs) have emerged as an important tool for the fabrication of in vitro models overcoming the challenges encountered in natural and synthetic materials due to their intrinsic properties, such as phase transition behavior, tunable biological properties, viscoelasticity, and easy processability. In this review article, we will delve into the use of ELRs for molecular models of intrinsically disordered proteins (IDPs), as well as for the development of in vitro 3D models for regenerative medicine. The easy processability of the ELRs and their rational design has allowed their use for the development of spheroids and organoids, or bioinks for 3D bioprinting. Thus, incorporating ELRs into the toolkit of biomaterials used for the fabrication of in vitro models, represents a transformative step forward in improving the accuracy, efficiency, and functionality of these models, and opening up a wide range of possibilities in combination with advanced biofabrication techniques that remains to be explored.

3.
Healthcare (Basel) ; 12(6)2024 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-38540588

RESUMO

Nowadays, obesity (OB) is one of the most important health problems in population-wide health. In addition to its physical consequences, it is a risk factor for the development of psychological problems, including body dissatisfaction (BD). This is why the treatment of BD is essential for its prevention. However, this has mostly been studied from a quantitative perspective, without focusing on the discomfort experienced by the person and the accompanying thoughts and emotions. In this study, 26 women with obesity (BMI > 30 kg/m2) participated, of whom 16 had high BD and 10 had low BD, as measured by the BSQ questionnaire. The women with high BD underwent six sessions of exposure to their own body in front of a mirror, recording the discomfort experienced with this vision during the session. In addition, all participants recorded positive and negative thoughts towards their body before and after these sessions. After the exposure treatment sessions, a reduction in symptomatology (BD, discomfort when visualizing one's own body) was observed, as well as a change in the thoughts expressed by the participants, both in quantity (fewer negative thoughts) and in quality (a more positive self-perception and/or in more respectful terms used towards themselves). In conclusion, such treatments prove to be effective in reducing subjective discomfort and body-related thoughts in women with obesity.

4.
Mater Today Bio ; 25: 100999, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38379933

RESUMO

Despite the remarkable progress in the generation of recombinant elastin-like (ELR) hydrogels, further improvements are still required to enhance and control their viscoelasticity, as well as limit the use of expensive chemical reagents, time-consuming processes and several purification steps. To alleviate this issue, the reactivity of carboxylic groups from glutamic (E) acid distributed along the hydrophilic block of an amphiphilic ELR (coded as E50I60) with amine groups has been studied through a one-pot amidation reaction in aqueous solutions, for the first time. By means of this approach, immediate conjugation of E50I60 with molecules containing amine groups has been performed with a high yield, as demonstrated by the 1H NMR and MALDI-TOF spectroscopies. This has resulted in the preparation of viscoelastic irreversible hydrogels through the "in-situ" cross-linking of E50I60 with another ELR (coded as VKV24) containing amine groups from lysines (K). The rheology analysis demonstrated that the gelation process takes place following a dual mechanism dependent on the ELR concentration: physical cross-linking of I60 block through the hydrophobic interactions, and covalent cross-linking of E50I60 with VKV24 through the amidation reaction. While the chemical network formed between the hydrophilic E50 block and VKV24 ELR preserves the elasticity of ELR hydrogels, the self-assembly of the I60 block through the hydrophobic interactions provides a tunable physical network. The presented investigation serves as a basis for generating ELR hydrogels with tunable viscoelastic properties promising for tissue regeneration, through an ''in-situ", rapid, scalable, economically and feasible one-pot method.

5.
Nurse Educ Pract ; 75: 103901, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38277804

RESUMO

AIM: We aimed to compare the debriefing experience, simulation assessment, reflection, anxiety and simulation satisfaction of using oral debriefing versus video-assisted debriefing after a simulated clinical session in an interdisciplinary cohort of health sciences students. BACKGROUND: Debriefing is a reflective process that takes place after a clinical simulation and that can be performed either in a traditional way (oral) or using video-assisted debriefing. DESIGN: A randomized controlled trial was conducted in 143 health sciences students (35.7% male, 61.5% female). METHODS: The simulation scenario was designed to evaluate the procedure for donning and doffing personal protective equipment. Differences in debriefing experience, simulation assessment, reflection, anxiety and satisfaction were assessed. RESULTS: Regarding debriefing experience, significant differences were observed for the category "learning" (34.9 (6.13) vs. 36.7 (3.89); p = 0.039). For simulation assessment, significantly higher scores for all categories were identified in video-assisted debriefing compared with oral debriefing (p<0.001). There were also significant differences between the oral debriefing versus video-assisted debriefing for the overall score of reflection ability (86.97 (10.55) vs. 90.74 (9.67); p=0.028) as well as for the category "reflective communication" (24.72 (3.77) vs 26.04 (4.07); p=0.047). Perceived satisfaction was significantly higher in the video-assisted debriefing group compared with oral debriefing group (p <0.001). For anxiety, no significant differences were observed between debriefing groups. CONCLUSION: Video-assisted debriefing after a simulated clinical session improves debriefing experience, simulation assessment, reflection and simulation satisfaction, but does not increase anxiety compared with oral debriefing among health sciences students.


Assuntos
Comunicação , Aprendizagem , Humanos , Masculino , Feminino , Ocupações em Saúde , Competência Clínica
6.
Sci Total Environ ; 904: 166774, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37660804

RESUMO

The increasing use of plastics and the growing concern about their impact on the environment and living beings makes it necessary to study how microplastics (MP) affect aquaculture systems. In order to gain an in-depth understanding of these systems, this study covers the water intake, the purification treatment at the inlet, the water in the culture tanks, as well as the feed used in the feeding and the organism itself. For this purpose, five samples were taken, both in the water line, feed and sea bass during the weeks of the experiment. It is shown that the available purification systems reduce the amount of MP entering from the receiving environment. However, new MP are observed in the sea bass tank, which may be due mainly to those added through the feed and found in the feed, as well as in the piping and other materials used in current aquaculture systems (PTFE, PA, among others). If focusing on the feed that can reach the consumer, in the case of this study, carried out with sea bass, some types of MP (PE, PTFE, PS and PA) were found in 4 head samples and 4 skin/muscle samples. Although inlet water purification systems manage to reduce a high percentage of MPs in the system, it is observed that there are other access routes that should be considered and reduced in aquaculture facilities to prevent them from reaching the human consumer.


Assuntos
Bass , Poluentes Químicos da Água , Animais , Humanos , Microplásticos , Plásticos , Bass/fisiologia , Aquicultura , Água , Politetrafluoretileno
7.
Polymers (Basel) ; 15(16)2023 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-37631515

RESUMO

Polylactic acid (PLA) is a biodegradable polymer that can replace petroleum-based polymers and is widely used in material extrusion additive manufacturing (AM). The reprocessing of PLA leads to a downcycling of its properties, so strategies are being sought to counteract this effect, such as blending with virgin material or creating nanocomposites. Thus, two sets of nanocomposites based respectively on virgin PLA and a blend of PLA and reprocessed PLA (rPLA) with the addition of 0, 3, and 7 wt% of titanium dioxide nanoparticles (TiO2) were created via a double screw extruder system. All blends were used for material extrusion for 3D printing directly from pellets without difficulty. Scanning electron micrographs of fractured samples' surfaces indicate that the nanoparticles gathered in agglomerations in some blends, which were well dispersed in the polymer matrix. The thermal stability and degree of crystallinity for every set of nanocomposites have a rising tendency with increasing nanoparticle concentration. The glass transition and melting temperatures of PLA/TiO2 and PLA/rPLA/TiO2 do not differ much. Tensile testing showed that although reprocessed material implies a detriment to the mechanical properties, in the specimens with 7% nano-TiO2, this effect is counteracted, reaching values like those of virgin PLA.

8.
J Clin Med ; 12(14)2023 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-37510865

RESUMO

The association between emergency department (ED) length of stay (EDLOS) with in-hospital mortality (IHM) in older patients remains unclear. This retrospective study aims to delineate the relationship between EDLOS and IHM in elderly patients. From the ED patients (n = 383,586) who visited an urban academic tertiary care medical center from January 2010 to December 2016, 78,478 older patients (age ≥60 years) were identified and stratified into three age subgroups: 60-74 (early elderly), 75-89 (late elderly), and ≥90 years (longevous elderly). We applied multiple machine learning approaches to identify the risk correlation trends between EDLOS and IHM, as well as boarding time (BT) and IHM. The incidence of IHM increased with age: 60-74 (2.7%), 75-89 (4.5%), and ≥90 years (6.3%). The best area under the receiver operating characteristic curve was obtained by Light Gradient Boosting Machine model for age groups 60-74, 75-89, and ≥90 years, which were 0.892 (95% CI, 0.870-0.916), 0.886 (95% CI, 0.861-0.911), and 0.838 (95% CI, 0.782-0.887), respectively. Our study showed that EDLOS and BT were statistically correlated with IHM (p < 0.001), and a significantly higher risk of IHM was found in low EDLOS and high BT. The flagged rate of quality assurance issues was higher in lower EDLOS ≤1 h (9.96%) vs. higher EDLOS 7 h

9.
Int J Mol Sci ; 24(7)2023 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-37047749

RESUMO

More than 260 million surgical procedures are performed worldwide each year. Although sutures and staples are widely used to reconnect tissues, they can cause further damage and increase the risk of infection. Bioadhesives have been proposed as an alternative to reconnect tissues. However, clinical adhesives that combine strong adhesion with cytocompatibility have yet to be developed. In this study, we explored the production of adhesives based on protein-engineered polymers bioinspired by the sequence of elastin (i.e., elastin-like recombinamers, ELRs). We hypothesized that the combination of polyphenols (i.e., tannic acid, TA) and ELRs would produce an adhesive coacervate (ELR+TA), as reported for other protein polymers such as silk fibroin (SF). Notably, the adhesion of ELR alone surpassed that of ELR+TA. Indeed, ELR alone achieved adhesive strengths of 88.8 ± 33.2 kPa and 17.0 ± 2.0 kPa on porcine bone and skin tissues, respectively. This surprising result led us to explore a multicomponent bioadhesive to encompass the complementary roles of elastin (mimicked here by ELR) and silk fibroin (SF), and subsequently mirror more closely the multicomponent nature of the extracellular matrix. Tensile testing showed that ELR+SF achieved an adhesive strength of 123.3 ± 60.2 kPa on porcine bone and excellent cytocompatibility. To express this in a more visual and intuitive way, a small surface of only 2.5 cm2 was able to lift at least 2 kg of weight. This opens the door for further studies focusing on the ability of protein-engineered polymers to adhere to biological tissues without further chemical modification for applications in tissue engineering.


Assuntos
Elastina , Fibroínas , Adesivos , Elastina/metabolismo , Fibroínas/farmacologia , Aderências Teciduais , Engenharia Tecidual/métodos , Animais , Suínos
10.
Pharmaceutics ; 15(3)2023 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-36986732

RESUMO

The 3D printing of titanium (Ti) offers countless possibilities for the development of personalized implants with suitable mechanical properties for different medical applications. However, the poor bioactivity of Ti is still a challenge that needs to be addressed to promote scaffold osseointegration. The aim of the present study was to functionalize Ti scaffolds with genetically modified elastin-like recombinamers (ELRs), synthetic polymeric proteins containing the elastin epitopes responsible for their mechanical properties and for promoting mesenchymal stem cell (MSC) recruitment, proliferation, and differentiation to ultimately increase scaffold osseointegration. To this end, ELRs containing specific cell-adhesive (RGD) and/or osteoinductive (SNA15) moieties were covalently attached to Ti scaffolds. Cell adhesion, proliferation, and colonization were enhanced on those scaffolds functionalized with RGD-ELR, while differentiation was promoted on those with SNA15-ELR. The combination of both RGD and SNA15 into the same ELR stimulated cell adhesion, proliferation, and differentiation, although at lower levels than those for every single moiety. These results suggest that biofunctionalization with SNA15-ELRs could modulate the cellular response to improve the osseointegration of Ti implants. Further investigation on the amount and distribution of RGD and SNA15 moieties in ELRs could improve cell adhesion, proliferation, and differentiation compared to the present study.

11.
Biomacromolecules ; 24(10): 4408-4418, 2023 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-36597885

RESUMO

The involvement of the extracellular matrix (ECM) in tumor progression has motivated the development of biomaterials mimicking the tumor ECM to develop more predictive cancer models. Particularly, polypeptides based on elastin could be an interesting approach to mimic the ECM due to their tunable properties. Here, we demonstrated that elastin-like recombinamer (ELR) hydrogels can be suitable biomaterials to develop breast cancer models. This hydrogel was formed by two ELR polypeptides, one containing sequences biodegradable by matrix metalloproteinase and cyclooctyne and the other carrying arginylglycylaspartic acid and azide groups to allow cell adhesion, biodegradability, and suitable stiffness through "click-chemistry" cross-linking. Our findings show that breast cancer or nontumorigenic breast cells showed high viability and cell proliferation for up to 7 days. MCF7 and MCF10A formed spheroids whereas MDA-MB-231 formed cell networks, with the expression of ECM and high drug resistance in all cases, evidencing that ELR hydrogels are a promising biomaterial for breast cancer modeling.


Assuntos
Neoplasias da Mama , Hidrogéis , Humanos , Feminino , Hidrogéis/farmacologia , Hidrogéis/química , Elastina/química , Neoplasias da Mama/tratamento farmacológico , Materiais Biocompatíveis , Peptídeos , Matriz Extracelular
12.
Biomacromolecules ; 24(10): 4419-4429, 2023 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-36696687

RESUMO

Multicomponent self-assembly offers opportunities for the design of complex and functional biomaterials with tunable properties. Here, we demonstrate how minor modifications in the molecular structures of peptide amphiphiles (PAs) and elastin-like recombinamers (ELs) can be used to generate coassembling tubular membranes with distinct structures, properties, and bioactivity. First, by introducing minor modifications in the charge density of PA molecules (PAK2, PAK3, PAK4), different diffusion-reaction processes can be triggered, resulting in distinct membrane microstructures. Second, by combining different types of these PAs prior to their coassembly with ELs, further modifications can be achieved, tuning the structures and properties of the tubular membranes. Finally, by introducing the cell adhesive peptide RGDS in either the PA or EL molecules, it is possible to harness the different diffusion-reaction processes to generate tubular membranes with distinct bioactivities. The study demonstrates the possibility to trigger and achieve minor but crucial differences in coassembling processes and tune material structure and bioactivity. The study demonstrates the possibility to use minor, yet crucial, differences in coassembling processes to tune material structure and bioactivity.


Assuntos
Materiais Biocompatíveis , Peptídeos , Peptídeos/química , Estrutura Molecular
13.
Urol Int ; 106(12): 1220-1225, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36318885

RESUMO

INTRODUCTION: Studies comparing different single-use flexible ureteroscope (su-fURS) models are lacking. The objective was to compare three types of su-fURS: the Uscope 3022 (PUSEN), LithoVue (Boston Scientific), and EU-scope (Innovex). METHODS: This was a retrospective study comparing the clinical outcomes from patients undergoing flexible ureteroscopy with one of the three su-fURS for upper urinary tract stone treatment between September 2019 and 2021. Analysis included total surgery and fluoroscopy time, post-procedure ureteral catheter, stone-free rate (SFR), and complications. RESULTS: There were 104 cases with the Uscope 3022, 141 with LithoVue, and 80 with EU-scope. Groups were comparable in terms of stone size, location and density, and prior double-J stent presence. Multivariate analysis showed no difference in terms of SFR: 79% (Uscope 3022), 77.5% (LithoVue), and 81% (EU-scope); p = 0.38. Significant differences were found for total surgery and fluoroscopy time, as well as ureteral access sheath use (p < 0.001), favoring the EU-scope group. DISCUSSION/CONCLUSION: The three devices evaluated are highly effective in treatment of kidney stones. Reasons for difference in total surgery and fluoroscopy time and access sheath use are not clear. However, this could be explained by technical aspects of these devices, such as external diameter, optical resolution, and field of view.


Assuntos
Ureteroscopia , Cálculos Urinários , Humanos , Estudos Retrospectivos
14.
Adv Healthc Mater ; 11(22): e2201646, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36099430

RESUMO

Spatiotemporal control of vascularization and innervation is a desired hallmark in advanced tissue regeneration. For this purpose, we design a 3D model scaffold, based on elastin-like recombinamer (ELR) hydrogels. This contains two interior and well-defined areas, small cylinders, with differentiated bioactivities with respect to the bulk. Both are constructed on a protease sensitive ELR with a fast-proteolyzed domain, but one bears a VEGF-mimetic peptide (QK) and the other a laminin-derived pentapeptide (IKVAV), to promote angiogenesis and neurogenesis, respectively. The outer bulk is based on a slow proteolytic sequence and RGD cell adhesion domains. In vitro studies show the effect of QK and IKVAV peptides on the promotion of endothelial cell and axon spreading, respectively. The subcutaneous implantation of the final 3D scaffold demonstrates the ability to spatiotemporally control angiogenesis and neurogenesis in vivo. Specifically, the inner small cylinder containing the QK peptide promotes fast endothelialization, whereas the one with IKVAV peptide promotes fast neurogenesis. Both, vascularization and innervation take place in advance of the bulk scaffold infiltration. This scaffold shows that it is possible to induce vascularization and innervation in predetermined areas of the scaffold well ahead to the bulk infiltration. That significantly increases the efficiency of the regenerative activity.


Assuntos
Elastina , Laminina , Elastina/farmacologia , Elastina/química , Laminina/farmacologia , Laminina/química , Fator A de Crescimento do Endotélio Vascular/farmacologia , Peptídeo Hidrolases , Peptídeos/farmacologia , Peptídeos/química , Hidrogéis/farmacologia , Hidrogéis/química , Neurogênese
15.
Front Bioeng Biotechnol ; 10: 918602, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35814011

RESUMO

Hindlimb ischemia is an unmet medical need, especially for those patients unable to undergo vascular surgery. Cellular therapy, mainly through mesenchymal stromal cell (MSC) administration, may be a potentially attractive approach in this setting. In the current work, we aimed to assess the potential of the combination of MSCs with a proangiogenic elastin-like recombinamer (ELR)-based hydrogel in a hindlimb ischemia murine model. Human bone marrow MSCs were isolated from four healthy donors, while ELR biomaterials were genetically engineered. Hindlimb ischemia was induced through ligation of the right femoral artery, and mice were intramuscularly injected with ELR biomaterial, 0.5 × 106 MSCs or the combination, and also compared to untreated animals. Tissue perfusion was monitored using laser Doppler perfusion imaging. Histological analysis of hindlimbs was performed after hematoxylin and eosin staining. Immunofluorescence with anti-human mitochondria antibody was used for human MSC detection, and the biomaterial was detected by elastin staining. To analyze the capillary density, immunostaining with an anti-CD31 antibody was performed. Our results show that the injection of MSCs significantly improves tissue reperfusion from day 7 (p = 0.0044) to day 21 (p = 0.0216), similar to the infusion of MSC + ELR (p = 0.0038, p = 0.0014), without significant differences between both groups. After histological evaluation, ELR hydrogels induced minimal inflammation in the injection sites, showing biocompatibility. MSCs persisted with the biomaterial after 21 days, both in vitro and in vivo. Finally, we observed a higher blood vessel density when mice were treated with MSCs compared to control (p<0.0001), but this effect was maximized and significantly different to the remaining experimental conditions when mice were treated with the combination of MSCs and the ELR biomaterial (p < 0.0001). In summary, the combination of an ELR-based hydrogel with MSCs may improve the angiogenic effects of both strategies on revascularization of ischemic tissues.

16.
Front Bioeng Biotechnol ; 10: 836386, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35832405

RESUMO

Design and fabrication of implants that can perform better than autologous bone grafts remain an unmet challenge for the hard tissue regeneration in craniomaxillofacial applications. Here, we report an integrated approach combining additive manufacturing with supramolecular chemistry to develop acellular mineralizing 3D printed scaffolds for hard tissue regeneration. Our approach relies on an elastin-like recombinamer (ELR) coating designed to trigger and guide the growth of ordered apatite on the surface of 3D printed nylon scaffolds. Three test samples including a) uncoated nylon scaffolds (referred to as "Uncoated"), b) ELR coated scaffolds (referred to as "ELR only"), and c) ELR coated and in vitro mineralized scaffolds (referred to as "Pre-mineralized") were prepared and tested for in vitro and in vivo performance. All test samples supported normal human immortalized mesenchymal stem cell adhesion, growth, and differentiation with enhanced cell proliferation observed in the "Pre-mineralized" samples. Using a rabbit calvarial in vivo model, 'Pre-mineralized' scaffolds also exhibited higher bone ingrowth into scaffold pores and cavities with higher tissue-implant integration. However, the coated scaffolds ("ELR only" and "Pre-mineralized") did not exhibit significantly more new bone formation compared to "Uncoated" scaffolds. Overall, the mineralizing coating offers an opportunity to enhance integration of 3D printed bone implants. However, there is a need to further decipher and tune their immunologic response to develop truly osteoinductive/conductive surfaces.

17.
Int J Biol Macromol ; 212: 193-201, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35594939

RESUMO

Steel corrosion is a global issue that affects safety and the economy. Currently, the homopolysaccharide (HoPS) structure of a novel lactic acid bacterium (LAB) is under study, as well as its application as a green corrosion inhibitor. Weissella cibaria FMy 2-21-1 is a LAB strain capable of producing HoPS in sucrose enriched media. The isolated and purified HoPS was characterized by different spectroscopic analyses as a linear α-1,6 dextran adopting a random coil conformation, with high molecular weight and extended size in water. The polysaccharide showed a semi-crystalline organization, which is a requirement for film formation. Its biocoating showed a grainy network structure, with a slightly lesser hydrophobic role in the aqueous environment than in the ionic one. The electrochemical measurements of the steel-HoPS coating showed that the biopolymer layer acts as an anodic-type corrosion inhibitor, with high resistance to corrosion by water and with chloride ions which prevent pitting, a corrosion process typical of bare steel. Few reports have cited the application of LAB HoPS as corrosive coating inhibitors. This work is the first to explore the influence of a structurally characterized dextran from Weissella cibaria strain as a potential steel corrosion inhibitor in ionic environments.


Assuntos
Dextranos , Weissella , Corrosão , Dextranos/química , Aço/química , Água , Weissella/química
18.
Invest Ophthalmol Vis Sci ; 63(4): 27, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-35486068

RESUMO

Purpose: Degenerative mechanisms of retinal neurodegenerative diseases (RND) share common cellular and molecular signalization pathways. Curative treatment does not exist and cell-based therapy, through the paracrine properties of mesenchymal stem cells (MSC), is a potential unspecific treatment for RND. This study aimed to evaluate the neuroprotective capability of human bone marrow (bm) MSC secretome and its potential to modulate retinal responses to neurodegeneration. Methods: An in vitro model of spontaneous retinal neurodegeneration was used to compare three days of monocultured neuroretina (NR), NR cocultured with bmMSC, and NR cultured with bmMSC secretome. We evaluated retinal morphology markers (Lectin peanut agglutinin, rhodopsin, protein kinase C α isoform, neuronal-specific nuclear protein, glial fibrillary acidic protein, TdT-mediated dUTP nick-end labeling, and vimentin) and proteins involved in apoptosis (apoptosis-inductor factor, caspase-3), necroptosis (MLKL), and autophagy (p62). Besides, we analyzed the relative mRNA expression through qPCR of genes involved in apoptosis (BAX, BCL2, CASP3, CASP8, CASP9), necroptosis (MLKL, RIPK1, RIPK3), autophagy (ATG7, BCLIN1, LC3B, mTOR, SQSTM1), oxidative stress (COX2, CYBA, CYBB, GPX6, SOD1, TXN2, TXNRD1) and inflammation (IL1, IL6, IL10, TGFb1, TNFa). Results: The bmMSC secretome preserves retinal morphology, limits pro-apoptotic- and pro-necroptotic-related gene and protein expression, modulates autophagy-related genes and proteins, and stimulates the activation of antioxidant-associated genes. Conclusions: The neuroprotective ability of the bmMSC secretome is associated with activation of antioxidant machinery, modulation of autophagy, and inhibition of apoptosis and necroptosis during retinal degeneration. The neuroprotective effect of bmMSC secretomes in the presence/absence of MSC looks similar. Our current results reinforce the hypothesis that the human bmMSC secretome slows retinal neurodegeneration and may be a therapeutic option for treating RND.


Assuntos
Células-Tronco Mesenquimais , Fármacos Neuroprotetores , Antioxidantes/farmacologia , Apoptose , Autofagia , Humanos , Fármacos Neuroprotetores/farmacologia , Estresse Oxidativo , Secretoma
19.
Pharmaceutics ; 14(2)2022 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-35214015

RESUMO

Cartilage diseases currently affect a high percentage of the world's population. Almost all of these diseases, such as osteoarthritis (OA), cause inflammation of this soft tissue. However, this could be controlled with biomaterials that act as an anti-inflammatory delivery system, capable of dosing these drugs over time in a specific area. The objective of this study was to incorporate etanercept (ETA) into porous three-layer scaffolds to decrease the inflammatory process in this soft tissue. ETA is a blocker of pro-inflammatory cytokines, such as tumour necrosis factor alpha (TNF-α) and interleukin 6 (IL-6). For this reason, the scaffold was built based on natural polymers, including chitosan and type I collagen. The scaffold was grafted next to subchondral bone using hydroxyapatite as filler. One of the biomaterials obtained was also crosslinked to compare its mechanical properties with the non-treated one. Both samples' physicochemical properties were studied with SEM, micro-CT and photoacoustic imaging, and their rheological properties were also compared. The cell viability and proliferation of the human chondrocyte C28/I2 cell line were studied in vitro. An in vitro and in vivo controlled release study was evaluated in both specimens. The ETA anti-inflammatory effect was also studied by in vitro TNF-α and IL-6 production. The crosslinked and non-treated scaffolds had rheological properties suitable for this application. They were non-cytotoxic and favoured the in vitro growth of chondrocytes. The in vitro and in vivo ETA release showed desirable results for a drug delivery system. The TNF-α and IL-6 production assay showed that this drug was effective as an anti-inflammatory agent. In an in vivo OA mice model, safranin-O and fast green staining was carried out. The OA cartilage tissue improved when the scaffold with ETA was grafted in the damaged area. These results demonstrate that this type of biomaterial has high potential for clinical applications in tissue engineering and as a controlled drug delivery system in OA articular cartilage.

20.
Front Neuroanat ; 16: 812487, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35221932

RESUMO

Retinal neurodegenerative diseases are the leading causes of visual impairment and irreversible blindness worldwide. Although the retinal response to injury remains closely similar between different retinal neurodegenerative diseases, available therapeutic alternatives are only palliative, too expensive, or very specific, such as gene therapy. In that sense, the development of broad-spectrum neuroprotective therapies seems to be an excellent option. In this regard, it is essential to identify molecular targets involved in retinal degeneration, such as cell death mechanisms. Apoptosis has been considered as the primary cell death mechanism during retinal degeneration; however, recent studies have demonstrated that the only use of anti-apoptotic drugs is not enough to confer good neuroprotection in terms of cell viability and preservation. For that reason, the interrelationship that exists between apoptosis and other cell death mechanisms needs to be characterized deeply to design future therapeutic options that simultaneously block the main cell death pathways. In that sense, the study aimed to characterize the programmed cell death (in terms of apoptosis and necroptosis) and autophagy response and modulation in retinal neurodegenerative diseases, using an in vitro model of spontaneous retinal neurodegeneration. For that purpose, we measured the mRNA relative expression through qPCR of a selected pool of genes involved in apoptosis (BAX, BCL2, CASP3, CASP8, and CASP9), necroptosis (MLKL, RIPK1, and RIPK3), and autophagy (ATG7, BCLIN1, LC3B, mTOR, and SQSTM1); besides, the immunoexpression of their encoding proteins (Casp3, MLKL, RIPK1, LC3B, and p62) were analyzed using immunohistochemistry. Our results showed an increase of pro-apoptotic and pro-necroptotic related genes and proteins during in vitro retinal neurodegeneration. Besides, we describe for the first time the modulation between programmed cell death mechanisms and autophagy in an in vitro retinal neurodegeneration model. This study reinforces the idea that cell death mechanisms are closely interconnected and provides new information about molecular signaling and autophagy along the retinal degeneration process.

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