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1.
Bioprocess Biosyst Eng ; 45(4): 679-688, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35015119

RESUMO

Biopolishing is a textile process that uses cellulases to improve the pilling resistance of fabrics. Although the process improves the pilling resistance, softness and color brightness of fabrics, it causes a significant loss of tensile strength in treated fabrics. The present work studied the use of cellulase immobilized on kaolin by adsorption and covalent bonding in biopolishing to get around this problem. The cellulase immobilization has been reported as promising alternative to overcome the inconvenient of biopolishing, but it has been very poorly explored. The results showed that cellulase immobilized by both covalent bonding and adsorption methods provided to the knitted fabric similar or superior pilling resistance to free cellulase, but with greater tensile strength. Immobilization also allowed for efficient recovery and reuse of the enzyme. The present work is a relevant contribution to the literature, since, as far as we know, it is the first work that shows it is possible to minimize the loss of tensile strength and also reuse the immobilized enzyme, giving a better-quality product and also contribution to reducing the cost of the polishing step.


Assuntos
Celulase , Celulases , Enzimas Imobilizadas , Caulim , Têxteis
2.
Curr Sports Med Rep ; 21(12): 448-453, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36508601

RESUMO

ABSTRACT: This narrative review aims to provide a general overview of the literature about frame running, which is a recent modality of Para-Athletics. Frame running is practiced by using a tricycle without pedals called PETRA RaceRunner, by people with moderate to severe cerebral palsy and other lower limb functional limitations. Briefly, the movement pattern is very similar to walking and running. This review includes studies from scientific databases and content of official sports web sites by using the keywords "framerunning," "racerunning," and "petra racerunning." According to our search, this narrative review highlighted three themes involving the practice of frame running, namely health and quality of life, sports classification, and training and testing in the frame running context.


Assuntos
Paralisia Cerebral , Corrida , Humanos , Qualidade de Vida , Paralisia Cerebral/diagnóstico , Caminhada , Extremidade Inferior
3.
Bioprocess Biosyst Eng ; 44(8): 1627-1637, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33686500

RESUMO

In the current research, endoglucanase, one of the enzymes of the cellulolytic complex, was immobilized on kaolin by two different techniques, adsorption, and covalent bonding. A comparative study was conducted between free, adsorbed, and covalently immobilized endoglucanase. For the covalent bonding, the kaolin particles were functionalized with 3-aminopropyltriethoxysilane (APTES) and activated with glutaraldehyde. Immobilization by adsorption was performed using the kaolin without any treatment. Recovered activities after the endoglucanase immobilization by adsorption and covalent bonding were found to be 60 ± 2.5 and 65 ± 3.5%, respectively. The studies of optima pH and temperature, as well as thermal stability, showed that the catalytic characteristic of the enzyme was maintained after the immobilization by both adsorption and covalent bonding. Even after 8 cycles of use, the endoglucanase immobilized by the two techniques retained about 86% of its initial activity. The results showed that the adsorption was as effective as covalent bonding for the immobilization of endoglucanase on kaolin. However, the adsorption technique seems to have a greater potential for use in future studies, as it is simpler, cheaper, and faster than covalent immobilization. Therefore, in this work it was demonstrated that endoglucanases can be immobilized efficiently on kaolin through a very simple immobilization protocol, offering a promising strategy for performing repeated enzymatic hydrolysis reactions.


Assuntos
Celulase/química , Enzimas Imobilizadas/metabolismo , Glutaral/química , Caulim/química , Propilaminas/química , Silanos/química , Adsorção , Biotecnologia/métodos , Catálise , Estabilidade Enzimática , Concentração de Íons de Hidrogênio , Hidrólise , Microscopia Eletrônica de Varredura , Tamanho da Partícula , Temperatura , Difração de Raios X
4.
Bioprocess Biosyst Eng ; 43(7): 1279-1286, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32189054

RESUMO

In this work, the free lipase Eversa® Transform 2.0 was used as a catalyst for enzymatic glycerolysis reaction in a solvent-free system. The product was evaluated by nuclear magnetic resonance (1H NMR) and showed high conversion related to hydroxyl groups. In sequence, the product of the glycerolysis was used as stabilizer and biopolyol for the synthesis of poly(urea-urethane) nanoparticles (PUU NPs) aqueous dispersion by the miniemulsion polymerization technique, without the use of a further surfactant in the system. Reactions resulted in stable dispersions of PUU NPs with an average diameter of 190 nm. After, the formation of the PUU NPs in the presence of concentrated lipase Eversa® Transform 2.0 was studied, aiming the lipase immobilization on the NP surface, and a stable enzymatic derivative with diameters around 231 nm was obtained. The hydrolytic enzymatic activity was determined using ρ-nitrophenyl palmitate (ρ-NPP) and the immobilization was confirmed by morphological analysis using transmission electron microscopy and fluorescence microscopy.


Assuntos
Enzimas Imobilizadas/imunologia , Glicerol/química , Lipase/metabolismo , Polímeros/química , Poliuretanos/química , Microscopia Eletrônica de Transmissão , Sonicação , Espectroscopia de Infravermelho com Transformada de Fourier
5.
World J Surg ; 43(11): 2920-2926, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31332490

RESUMO

BACKGROUND: In the last decade, robotic video-assisted thoracic surgery (R-VATS) has grown significantly and consolidated as an alternative to video-assisted thoracic surgery. The objective of this study is to present the implementation as well as the experience with R-VATS accumulated by 2 Brazilian groups. We also compared the outcomes of procedures performed during the learning curve and after a more mature experience. METHODS: Retrospective cohort study included all R-VATS procedures performed since April 2015 until April 2018. We describe the process of implantation of robotic surgery, highlighting the peculiarities and difficulties found in a developing country. Moreover, we reported our descriptive results and compared the first 60 patients to the subsequent cases. RESULTS: Two hundred and five patients included 101 females/104 males. Mean age was 61.7 years. There were hundred and sixty-four pulmonary resections, 39 resections of mediastinal lesions, 1 diaphragmatic plication, and 1 resection of a hilar tumor. Median operative times were 205 min for lung resections and 129 min for mediastinal. There was no conversion to VATS or thoracotomy or major intraoperative complications. Median length of stay was 3 days for pulmonary resections and 1 day for mediastinal. Postoperative complications occurred in 35 cases (17.0%)-prolonged air leak was the most common (17 cases). One fatality occurred in an elderly patient with pneumonia and sepsis (0.4%). Comparison of the first 60 patients (learning curve) with subsequent 145 patients (consolidated experience) showed significant differences in surgical and ICU time, both favoring consolidated experience. CONCLUSIONS: Our results were comparable to the literature. Robotic thoracic surgery can be safely and successfully implemented in tertiary hospitals in emerging countries provided that all stakeholders are involved and compromised with the implementation process.


Assuntos
Países em Desenvolvimento , Neoplasias do Mediastino/cirurgia , Procedimentos Cirúrgicos Robóticos/estatística & dados numéricos , Cirurgia Torácica Vídeoassistida/estatística & dados numéricos , Idoso , Brasil , Feminino , Humanos , Complicações Intraoperatórias/etiologia , Curva de Aprendizado , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Duração da Cirurgia , Pneumonectomia/métodos , Complicações Pós-Operatórias/etiologia , Estudos Retrospectivos , Procedimentos Cirúrgicos Robóticos/efeitos adversos , Cirurgia Torácica/organização & administração , Cirurgia Torácica/estatística & dados numéricos , Cirurgia Torácica Vídeoassistida/efeitos adversos , Cirurgia Torácica Vídeoassistida/métodos
6.
Bioprocess Biosyst Eng ; 42(7): 1165-1173, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30927054

RESUMO

Endoglucanases are an enzyme of cellulases complex that has a great potential for many technological applications. One of the issues of its use concerns the recovery and reuse of this enzyme. Thus, in this study, the use of a surface-modified kaolin was evaluated to immobilize endoglucanase and evaluate the enzyme activity for its reuse. Kaolin was surface modified with 3-aminopropyltriethoxysilane (APTES) and glutaraldehyde (GA). In addition, the properties of the immobilized enzyme were investigated and compared with those of the free enzyme. Results showed that the optimal pH value of endoglucanase was not affected by the immobilization process but showed a broader range of optimal temperature compared to free enzyme. Immobilization on kaolin allowed fast and easy cellulase recovery with a loss of enzyme activity of only 20% after eight cycles of use. These results indicate that kaolin is a promising substitute to the currently synthetic supports studied for cellulases immobilization with the advantage of being abundant in nature, resistant to microbial attack, chemically and mechanically stable.


Assuntos
Celulase/química , Enzimas Imobilizadas/química , Caulim/química , Estabilidade Enzimática , Concentração de Íons de Hidrogênio , Temperatura
7.
Pharm Dev Technol ; 24(5): 593-599, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30457422

RESUMO

The current paucity of effective and affordable drugs for the treatment of leishmaniasis renders the search for new therapeutic alternatives a priority. Gallic acid-related compounds display anti-parasitic activities and their incorporation into drug carrier systems, such as polymeric nanoparticles may be a viable alternative for leishmaniasis treatment. Therefore, this study focused on the synthesis and characterization of octyl gallate (G8) loaded poly(methyl methacrylate) (PMMA) nanoparticles via miniemulsion polymerization in order to increase the leishmanicidal activity of this compound. G8 loaded PMMA nanoparticles presented a spherical morphology with a mean size of 108 nm, a negatively charged surface (-33 ± 5 mV) and high encapsulation efficiency (83% ± 5). Fourier-transform infrared spectroscopy and X-ray diffraction analysis confirmed that G8 was encapsulated in PMMA nanoparticles and presented a biphasic release profile. The G8 loaded PMMA nanoparticles did not present cytotoxic effect on human red blood cells. G8 loaded PMMA nanoparticles displayed a leishmanicidal activity almost three times higher than free G8 while the cytotoxic activity against human THP-1 cells remained unchanged.


Assuntos
Portadores de Fármacos/química , Ácido Gálico/análogos & derivados , Leishmania/efeitos dos fármacos , Polimetil Metacrilato/química , Tripanossomicidas/administração & dosagem , Tripanossomicidas/farmacologia , Células CACO-2 , Linhagem Celular , Liberação Controlada de Fármacos , Emulsões/química , Ácido Gálico/administração & dosagem , Ácido Gálico/química , Ácido Gálico/farmacologia , Hemólise/efeitos dos fármacos , Humanos , Leishmaniose/tratamento farmacológico , Nanopartículas/química , Nanopartículas/ultraestrutura , Tripanossomicidas/química
8.
Bioprocess Biosyst Eng ; 41(5): 585-591, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29350294

RESUMO

Benzyl propionate is an aromatic ester that possesses a fruity odor and is usually found in nature in the composition of some fruits such as plums and melons. This work aimed for the benzyl propionate synthesis by esterification using a new immobilized enzyme preparation with low-cost material from Candida antarctica (NS 88011) and three commercial immobilized lipases (Novozym 435, Lipozyme TL-IM and Lipozyme RM-IM). Novozym 435 had the best performance even when the solvent tert-butanol was absent of the reaction medium. Results from a 22 factorial design showed that an increase in the enzyme amount led to a higher conversion, even when the temperature was kept at the low value. Currently, no research had synthesized successfully benzyl propionate via esterification mediated by lipases; and we reached an ester conversion of ~ 44% after 24 h indicating that it is a promising route for benzyl propionate biotechnological production.


Assuntos
Candida/enzimologia , Enzimas Imobilizadas/química , Ésteres/síntese química , Proteínas Fúngicas/química , Lipase/química , Biocatálise , Ésteres/química
9.
J Mater Chem B ; 12(12): 3047-3062, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38421173

RESUMO

Many efforts have been devoted to bone tissue to regenerate damaged tissues, and the development of new biocompatible materials that match the biological, mechanical, and chemical features required for this application is crucial. Herein, a collagen-decorated scaffold was prepared via electrospinning using a synthesized unsaturated copolyester (poly(globalide-co-pentadecalactone)), followed by two coupling reactions: thiol-ene functionalization with cysteine and further conjugation via EDC/NHS chemistry with collagen, aiming to design a bone tissue regeneration device with improved hydrophilicity and cell viability. Comonomer ratios were varied, affecting the copolymer's thermal and chemical properties and highlighting the tunable features of this copolyester. Functionalization with cysteine created new carboxyl and amine groups needed for bioconjugation with collagen, which is responsible for providing biological and structural integrity to the extra-cellular matrix. Bioconjugation with collagen turned the scaffold highly hydrophilic, decreasing its contact angle from 107 ± 2° to 0°, decreasing the copolymer crystallinity by 71%, and improving cell viability by 85% compared with the raw scaffold, thus promoting cell growth and proliferation. The highly efficient and biosafe strategy to conjugate polymers and proteins created a promising device for bone repair in tissue engineering.


Assuntos
Cisteína , Alicerces Teciduais , Alicerces Teciduais/química , Colágeno/química , Osso e Ossos , Regeneração Óssea , Polímeros
10.
J Thorac Dis ; 16(2): 1724-1729, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38505023

RESUMO

Sternal cleft (SC) is a rare congenital affection caused by the absence of sternal bar union. Diagnosis is generally made after birth due to paradoxical midline movement, although it can be made prenatally by ultrasonography. A computerized tomography scan (CT scan) after birth is generally used to confirm the diagnosis, assess other intrathoracic conditions, classify the SC, and plan for surgery. SC can be classified as complete or incomplete. A complete SC has a full gap between sternal bars. An incomplete SC is subdivided into superior or inferior, related to the point of bone fusion between the sternal bars. The goal of surgical treatment is to protect mediastinal structures. Many authors advocate the repair in newborn patients, although it can be performed in older patients. The main argument in its favor is the chest's flexibility, with a reduced risk of compression of the mediastinal structures. There are several cases of series and distinct surgical techniques in the literature. Some authors have suggested the use of autologous tissue, prosthetic material such as mesh, or titanium plates and screws. Although difficulties are often encountered in surgical access, they have not been discussed. Therefore, we are promoting modifications to the technique in response to this. The purpose is to show innovations, and how to deal with adversity during the procedure.

11.
Clinics (Sao Paulo) ; 79: 100338, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38359698

RESUMO

INTRODUCTION: Almost 20 % of patients with Non-Seminomatous Germinative Cell Tumors (NSGCT) will require intrathoracic metastasectomy after chemotherapy. The authors aim to determine their long-term survival rates. METHODS: Retrospective study including patients with NSGCT and intrathoracic metastasis after systemic therapy from January 2011 to June 2022. Treatment outcomes and overall survival were analyzed with the Kaplan-Meier method. RESULTS: Thirty-seven male patients were included with a median age of 31.8 years. Six presented with synchronous mediastinum and lung metastasis, nine had only lung, and 22 had mediastinal metastasis. Over half had retroperitoneal lymph node metastasis. Twenty-two had dissimilar pathologies, with a discordance rate of 62 %. Teratoma and embryonal carcinoma were the prevalent primary tumor types, 40.5 % each, while teratoma was predominant (70.3 %) in the metastasis group. Thoracotomy was the main surgical approach (39.2 %) followed by VATS (37.2 %), cervico-sternotomy (9.8 %), sternotomy (5.8 %), and clamshell (3.9 %). Lung resection was performed in 40.5 % of cases. Overall, 10-year survival rates were 94.3 % with no surgical-related mortality. CONCLUSION: Multimodality treatment with systemic therapy followed by radical surgery offers a high cure rate to patients with intrathoracic metastatic testicular germ cell tumors.


Assuntos
Metastasectomia , Neoplasias Embrionárias de Células Germinativas , Teratoma , Neoplasias Testiculares , Humanos , Masculino , Adulto , Neoplasias Testiculares/cirurgia , Neoplasias Testiculares/tratamento farmacológico , Neoplasias Testiculares/patologia , Estudos Retrospectivos , Metastasectomia/métodos , Neoplasias Embrionárias de Células Germinativas/cirurgia , Teratoma/patologia , Teratoma/cirurgia , Excisão de Linfonodo/métodos
12.
Fundam Res ; 3(1): 93-101, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38933561

RESUMO

Fragmentation/disassembly of fiber-like micelles generated by living crystalline-driven self-assembly (CDSA) is usually encountered in aqueous media, which hinders the applications of micelles. Herein, we report the generation of uniform fiber-like micelles consisting of a π-conjugated oligo(p-phenylenevinylene) core and a cross-linking silica shell with grafted poly(ethylene glycol) (PEG) chains by the combination of living CDSA, silica chemistry and surface grafting-onto strategy. Owing to the presence of crosslinking silica shell and the outmost PEG chains, the resulting micelles exhibit excellent dispersity and colloidal stability in PBS buffer, BSA aqueous solution and upon heating at 80 °C for 2 h without micellar fragmentation/disassembly. The micelles also show negligible cytotoxicity toward both HeLa cervical cancer and HEK239T human embryonic kidney cell lines. Interestingly, micelles with L n of 156 nm show the "stealth" property with no significant uptake by HeLa cells, whereas some certain amounts of micelles with L n of 535 nm can penetrate into HeLa cells, showing length-dependent cellular uptake behaviors. These results provide a route to prepare uniform, colloidally stable fiber-like nanostructures with tunable length and functions derived for biomedical applications.

13.
Pharmaceutics ; 15(3)2023 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-36986860

RESUMO

Superparamagnetic iron oxide nanoparticles (SPIONs) have their use approved for the diagnosis/treatment of malignant tumors and can be metabolized by the organism. To prevent embolism caused by these nanoparticles, they need to be coated with biocompatible and non-cytotoxic materials. Here, we synthesized an unsaturated and biocompatible copolyester, poly (globalide-co-ε-caprolactone) (PGlCL), and modified it with the amino acid cysteine (Cys) via a thiol-ene reaction (PGlCLCys). The Cys-modified copolymer presented reduced crystallinity and increased hydrophilicity in comparison to PGlCL, thus being used for the coating of SPIONS (SPION@PGlCLCys). Additionally, cysteine pendant groups at the particle's surface allowed the direct conjugation of (bio)molecules that establish specific interactions with tumor cells (MDA-MB 231). The conjugation of either folic acid (FA) or the anti-cancer drug methotrexate (MTX) was carried out directly on the amine groups of cysteine molecules present in the SPION@PGlCLCys surface (SPION@PGlCLCys_FA and SPION@PGlCLCys_MTX) by carbodiimide-mediated coupling, leading to the formation of amide bonds, with conjugation efficiencies of 62% for FA and 60% for MTX. Then, the release of MTX from the nanoparticle surface was evaluated using a protease at 37 °C in phosphate buffer pH~5.3. It was found that 45% of MTX conjugated to the SPIONs were released after 72 h. Cell viability was measured by MTT assay, and after 72 h, 25% reduction in cell viability of tumor cells was observed. Thus, after a successful conjugation and subsequent triggered release of MTX, we understand that SPION@PGlCLCys has a strong potential to be treated as a model nanoplatform for the development of treatments and diagnosis techniques (or theranostic applications) that can be less aggressive to patients.

14.
Food Res Int ; 173(Pt 1): 113295, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37803607

RESUMO

Researchers have concentrated efforts in the search for natural-based reversible inhibitors for cholinesterase enzymes as they may play a key role in the treatment of degenerative diseases. Diverse plant alkaloids can inhibit the action of acetylcholinesterase and, among them, berberine is a promising bioactive. However, berberine has poor water solubility and low bioavailability, which makes it difficult to use in treatment. The solid dispersion technique can improve the water affinity of hydrophobic substances, but berberine solid dispersions have not been extensively studied. Safety testing is also essential to ensure that the berberine-loaded solid dispersions are safe for use. This study investigated the effectiveness of berberine-loaded solid dispersions (SD) as inhibitors of acetylcholinesterase enzyme (AChE). Docking simulation was used to investigate the influence of berberine on AChE, and in vitro assays were conducted to confirm the enzymatic kinetics of AChE in the presence of berberine. Berberine SD also showed improved cytotoxic effects on tumoral cells when dispersed in aqueous media. In vivo assays using Allium cepa were implemented, and no cytotoxicity/genotoxicity was found for the berberine solid dispersion. These results suggest that berberine SD could be a significant step towards safe nanostructures for use in the treatment of neurodegenerative diseases.


Assuntos
Alcaloides , Berberina , Nanopartículas , Berberina/farmacologia , Berberina/química , Acetilcolinesterase , Água
15.
Clinics (Sao Paulo) ; 77: 100098, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36041370

RESUMO

OBJECTIVE: Empyema is a complication of talc-pleurodesis that may lead to further surgical intervention and death. Therefore, the present study's objective was to identify the risk factors for the development of post-pleurodesis empyema after talc slurry pleurodesis in order to better select patients for this procedure and minimize its morbidity. METHODS: Patients with malignant pleural effusion who underwent talc slurry pleurodesis at the present institution from January 2018 to January 2020 were retrospectively analyzed. Post-pleurodesis empyema was defined as pleural infection up to 30 days after pleurodesis. Using Cox regression analysis, significant prognostic factors for the development of empyema were examined. RESULTS: Of the 86 patients identified for inclusion in the study, 62 were women (72%). Their mean age was 56.3±12.6 years. The median pleural drainage time was 9 days, and 20 patients (23.3%) developed empyema. In the univariate analysis, both drainage time (p = 0.038) and the use of antibiotics prior to pleurodesis (p < 0.001) were risk factors for pleural empyema. Multivariate analysis also identified the use of antibiotics as an independent risk factor (Odds Ratio [OR] 9.81; 95% Confidence Interval [95% CI] 2.87‒33.54). Although the pulmonary expansion was not associated with empyema in the multivariate analysis, patients with less than 50% pulmonary expansion had a 4.5-times increased risk of empyema (95% CI 0.90‒22.86; p = 0.067), and patients with 50‒70% pulmonary expansion had a 3.8-times increased risk of empyema (95% CI 0.98‒15; p = 0.053) after pleurodesis. CONCLUSION: The study suggests that antibiotic therapy prior to talc slurry pleurodesis may increase the risk of developing empyema. Furthermore, pleurodesis should be considered with caution in patients with long-duration chest tube placement and incomplete lung expansion.


Assuntos
Empiema Pleural , Derrame Pleural Maligno , Adulto , Idoso , Antibacterianos , Empiema Pleural/complicações , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Derrame Pleural Maligno/etiologia , Derrame Pleural Maligno/terapia , Pleurodese/efeitos adversos , Pleurodese/métodos , Estudos Retrospectivos , Fatores de Risco , Talco/efeitos adversos
16.
J Biomed Mater Res B Appl Biomater ; 110(3): 702-711, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34619018

RESUMO

Poly(thioether-ester) (PTEe) nanoparticles obtained by thiol-ene polymerization have received attention of many researchers due to several advantages, including, biocompatibility and biodegradability. The search for new nanomaterials requires toxicity studies to assess potential toxic effects of their administration. Therefore, the aim of this study was to evaluate the in vivo acute toxicity of PTEe and poly(thioether-ester)-coated magnetic nanoparticles prepared by thiol-ene polymerization in miniemulsion. These nanoparticles presented a mean size of approximately 120 nm, spherical morphology, and negative surface charge. Doses of 40 mg/kg were administered intraperitoneally to Swiss mice and nociceptive, behavioral and biochemical parameters were investigated in five different organs. None of the nanoparticles led to any alterations in the nociceptive and behavioral responses. Biochemical alterations were observed in liver, decreasing the sulfhydryl and glutathione (GSH) levels, suggesting the dependence of the GSH metabolism in the elimination of the nanoparticles. In general, both nanoparticle types did not cause disturbances in biochemical parameters analyzed in others organs. These results suggest that both nanoparticle types did not induce acute toxicity to the different organs evaluated, reinforcing the biocompatibility of PTEe nanoparticles synthetized by thiol-ene polymerization.


Assuntos
Nanopartículas , Sulfetos , Animais , Ésteres , Nanopartículas Magnéticas de Óxido de Ferro , Camundongos , Nanopartículas/toxicidade , Polimerização , Compostos de Sulfidrila , Sulfetos/toxicidade
17.
ACS Appl Nano Mater ; 5(1): 642-653, 2022 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-35098045

RESUMO

The COVID-19 pandemic, caused by the fast transmission and spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is currently considered a serious health problem, requiring an effective strategy to contain SARS-CoV-2 dissemination. For this purpose, epitopes of the SARS-CoV-2 spike (S) and sucleocapsid (N) proteins were identified by bioinformatics tools, and peptides that mimic these epitopes were chemically synthesized and then conjugated to superparamagnetic nanoparticles (SPMNPs). Three peptides from S protein and three from N protein were used as antigens in a conventional enzyme-linked immunosorbent assay (ELISA) against serum samples from COVID-19-positive patients, or from healthy donors, collected before the pandemic. Three peptides were effective as antigens in conventional peptide-based ELISA, achieving 100% sensitivity and specificity, with high accuracy. The best-performing peptides, p2pS, p1pN, and p3pN, were associated with superparamagnetic nanoparticles (SPMNPs) and were used to perform nanomagnetic peptide-based ELISA. The p2pS-SPMNP conjugate presented 100% sensitivity and specificity and excellent accuracy (area under the curve (AUC) = 1.0). However, p1pN and p3pN peptides, when conjugated to SPMNPs, did not preserve the capacity to differentiate positive sera from negative sera in all tested samples, yet both presented sensitivity and specificity above 80% and high accuracy, AUC > 0.9. We obtained three peptides as advantageous antigens for serodiagnosis. These peptides, especially p2pS, showed promising results in a nanomagnetic peptide-based ELISA and may be suitable as a precoated antigen for commercial purposes, which would accelerate the diagnosis process.

18.
J Biomater Appl ; 37(4): 668-682, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35705485

RESUMO

Objectives: This article aimed to investigate the effects of the association between photobiomodulation and hyaluronic acid incorporated in lipid nanoparticles in an epithelial lesion model in inflammatory parameters and oxidative stress. Methods: Eighty Wistar rats were randomly assigned to the following groups: epithelial lesion group (EL); EL+PBM; EL+HA; EL+SLNs; EL+SLNs-HA; EL+PBM+HA; EL+PBM+SLNs; EL+PBM+SLNs-HA. The animals were anesthetized with 4% isofluorane after shaving and induced to an epithelial lesion. Topical treatment with a gel containing HA (0.9%) and/or SLNs (10 mg/mL) and with laser irradiation occurred daily for 1 week. Results: The results showed an increase in wound contraction on the seventh day in the LE + LBM + AH-NPL group, a reduction in pro-inflammatory cytokines (IL-6, IL-1ß, and TNF-α), an increase in anti-inflammatory cytokines (IL- 4 and IL-10) and TGF-ß. The levels of pro-inflammatory cytokine IL-4 and TGF-ß also showed an increase in the LE + NPL-AH, LE + FBM + AH, LE + FBM + NPL and LE + FBM + NPL-AH groups. Regarding oxidative stress parameters, the levels of DCF and nitrite decreased in the combined therapy group when compared to the control group, as well as oxidative damage (carbonyl and sulfhydryl). In the antioxidant defense, there was an increase in GSH and SOD in the combination therapy group. Histological analysis showed a reduction in inflammatory infiltrate in the combination therapy group. The number of fibroblasts and the compaction of collagen fibers did not obtain significant responses. Conclusions: Results analyzed together showed that the combined therapy favored the repair process, and that studies can be carried out to enhance the histological analysis therapy favored the tissue repair process and that studies can be carried out to enhance the histological analysis.


Assuntos
Ácido Hialurônico , Terapia com Luz de Baixa Intensidade , Animais , Antioxidantes/farmacologia , Colágeno/farmacologia , Citocinas , Ácido Hialurônico/farmacologia , Ácido Hialurônico/uso terapêutico , Interleucina-10 , Interleucina-4 , Interleucina-6 , Lipossomos , Terapia com Luz de Baixa Intensidade/métodos , Nanopartículas , Nitritos/farmacologia , Ratos , Ratos Wistar , Superóxido Dismutase/farmacologia , Fator de Crescimento Transformador beta/farmacologia , Fator de Necrose Tumoral alfa , Cicatrização
19.
Eur J Pharmacol ; 923: 174934, 2022 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-35367420

RESUMO

Leishmaniasis is a neglected tropical disease that has a wide spectrum of clinical manifestations, ranging from visceral to cutaneous, with millions of new cases and thousands of deaths notified every year. The severity of the disease and its various clinical forms are determined by the species of the causative agent, Leishmania, as well as the host's immune response. Major challenges still exist in the diagnosis and treatment of leishmaniasis, and there is no vaccine available to prevent this disease in humans. Nanotechnology has emerged as a promising tool in a variety of fields. In this review, we highlight the main and most recent advances in nanomedicine to improve the diagnosis and treatment, as well as for the development of vaccines, for leishmaniasis. Nanomaterials are nanometric in size and can be produced by a variety of materials, including lipids, polymers, ceramics, and metals, with varying structures and morphologies. Nanotechnology can be used as biosensors to detect antibodies or antigens, thus improving the sensitivity and specificity of such immunological and molecular diagnostic tests. While in treatment, nanomaterials can act as drug carriers or, be used directly, to reduce any toxic effects of drug compounds to the host and to be more selective towards the parasite. Furthermore, preclinical studies show that different nanomaterials can carry different Leishmania antigens, or even act as adjuvants to improve a Th1 immune response in an attempt to produce an effective vaccine.


Assuntos
Leishmania , Leishmaniose , Vacinas , Portadores de Fármacos , Humanos , Leishmaniose/diagnóstico , Leishmaniose/tratamento farmacológico , Leishmaniose/prevenção & controle , Nanomedicina , Nanotecnologia , Vacinas/farmacologia
20.
ACS Appl Bio Mater ; 4(2): 1552-1562, 2021 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-35014505

RESUMO

Poly(ε-caprolactone) (PCL) is commonly used in devices for tissue reconstruction due to its biocompatibility and suitable mechanical properties. However, its high crystallinity and hydrophobicity do not favor cell adhesion and difficult polymer bioresorption. To improve these characteristics, the development of engineered scaffolds for tissue regeneration, based on poly(globalide-co-ε-caprolactone) (PGlCL) covalently bonded with N-acetylcysteine (PGlCL-NAC) was proposed. The scaffolds were obtained from polymer blends of PCL and PGlCL-NAC, using the electrospinning technique. The use of PGlCL-NAC allowed for the modification of the physical and chemical properties of PCL electrospun scaffolds, including an expressive reduction in the fiber's diameter, hydrophobicity, and crystallinity. All electrospun scaffolds showed no cytotoxicity against fibroblasts (McCoy cells). In vitro biocompatibility assays showed that all tested scaffolds provided high cell viability and proliferation in short-term (NRU, MTT, and nuclear morphology assays) and long-term (clonogenic assay) assays. Nevertheless, PGlCL-NAC based scaffolds have favored the survival and proliferation of the cells in comparison to PCL scaffolds. Cell adhesion on the scaffolds assessed by electronic microscopy images confirmed this behavior. These results suggest that the incorporation of PGlCL-NAC in scaffolds for tissue regeneration could be a promising strategy to improve cell-surface interactions and contribute to the development of more efficiently engineered biomedical devices.


Assuntos
Acetilcisteína/química , Caproatos/metabolismo , Fibroblastos/metabolismo , Lactonas/metabolismo , Poliésteres/química , Engenharia Tecidual/métodos
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