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1.
Curr Issues Mol Biol ; 46(6): 5845-5865, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38921020

RESUMO

Sickle cell anemia (SCA), the most common form of sickle cell disease (SCD), is a genetic blood disorder. Red blood cells break down prematurely, causing anemia and often blocking blood vessels, leading to chronic pain, organ damage, and increased infection risk. SCD arises from a single-nucleotide mutation in the ß-globin gene, substituting glutamic acid with valine in the ß-globin chain. This review examines treatments evaluated through randomized controlled trials for managing SCD, analyzes the potential of functional foods (dietary components with health benefits) as a complementary strategy, and explores the use of bioactive compounds as functional food ingredients. While randomized trials show promise for certain drugs, functional foods enriched with bioactive compounds also hold therapeutic potential. Further research is needed to confirm clinical efficacy, optimal dosages, and specific effects of these compounds on SCD, potentially offering a cost-effective and accessible approach to managing the disease.

2.
Cryo Letters ; 43(4): 246-254, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36626128

RESUMO

BACKGROUND: Prochilodus vimboides populations are being reduced in rivers due to changes in their habitat, overfishing, urbanization, and pollution. OBJECTIVE: To evaluate the effect of sperm extender solutions for short-term storage and cryosolutions for freezing sperm of Prochilodus vimboides. MATERIALS AND METHODS: For short-term storage, the sperm was diluted in 0.9% NaCl, 1.2% NaCl, 5% glucose, 5% BTS, or 6% MIII. Sperm motility was evaluated after 0, 24, 48, and 72 h of short-term storage at 4-6 degree C. For cryopreservation, sperm samples were diluted in the same extenders and factorially combined with three cryoprotectants (dimethylsulfoxide, methyl glycol, and ethylene glycol). After thawing, sperm motility and oxidative stress parameters were evaluated. RESULTS: Dilution of samples in BTS preserved sperm motility >40% for up to 48 h. Samples cryopreserved in 5% glucose and methylglycol presented higher sperm motility, lower catalase, and lipid peroxidation activities. CONCLUSION: Prochilodus vimboides sperm can be cooled for up to 48 h in an extender solution of 5% BTS and cryopreserved in 5% glucose and methyl glycol. doi.org/10.54680/fr22410110612.


Assuntos
Caraciformes , Preservação do Sêmen , Animais , Masculino , Criopreservação , Sêmen , Conservação dos Recursos Naturais , Motilidade dos Espermatozoides , Pesqueiros , Espermatozoides , Crioprotetores/farmacologia , Etilenoglicol/farmacologia , Propilenoglicol/farmacologia , Glucose/farmacologia
3.
J Mater Sci Mater Med ; 30(3): 32, 2019 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-30840132

RESUMO

In the last few years, additive manufacturing (AM) has been gaining great interest in the fabrication of complex structures for soft-to-hard tissues regeneration, with tailored porosity, and boosted structural, mechanical, and biological properties. 3D printing is one of the most known AM techniques in the field of biofabrication of tissues and organs. This technique opened up opportunities over the conventional ones, with the capability of creating replicable, customized, and functional structures that can ultimately promote effectively different tissues regeneration. The uppermost component of 3D printing is the bioink, i.e. a mixture of biomaterials that can also been laden with different cell types, and bioactive molecules. Important factors of the fabrication process include printing fidelity, stability, time, shear-thinning properties, mechanical strength and elasticity, as well as cell encapsulation and cell-compatible conditions. Collagen-based materials have been recognized as a promising choice to accomplish an ideal mimetic bioink for regeneration of several tissues with high cell-activating properties. This review presents the state-of-art of the current achievements on 3D printing using collagen-based materials for hard tissue engineering, particularly on the development of scaffolds for bone and cartilage repair/regeneration. The ultimate aim is to shed light on the requirements to successfully print collagen-based inks and the most relevant properties exhibited by the so fabricated scaffolds. In this regard, the adequate bioprinting parameters are addressed, as well as the main materials properties, namely physicochemical and mechanical properties, cell compatibility and commercial availability, covering hydrogels, microcarriers and decellularized matrix components. Furthermore, the fabrication of these bioinks with and without cells used in inkjet printing, laser-assisted printing, and direct in writing technologies are also overviewed. Finally, some future perspectives of novel bioinks are given.


Assuntos
Bioimpressão/métodos , Colágeno/química , Engenharia Tecidual/métodos , Animais , Materiais Biocompatíveis , Osso e Ossos/patologia , Cartilagem/patologia , Desenho Assistido por Computador , Gelatina/química , Dureza , Humanos , Hidrogéis/química , Lasers , Porosidade , Impressão Tridimensional , Medicina Regenerativa/métodos , Alicerces Teciduais/química
4.
J Appl Microbiol ; 125(4): 1208-1215, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29920871

RESUMO

AIMS: To improve RT-qPCR with an internal control and a synthetic standard curve to detect HEV in HIV co-infected patients. METHODS AND RESULTS: A single-stranded RNA (ssRNA) and a double-stranded DNA (dsDNA) synthetic curve were designed, compared to the international reference panel for HEV genotypes, and tested to quantify and detect a reference panel for HEV genotypes. The detection limit of the RNA synthetic curve (50 copies per ml) was better than the DNA synthetic curve (100 copies per ml) and the WHO standard curve (250 copies per ml). Then, 280 serum samples from HIV-positive patients were tested for HEV RNA, which was detected in 3·6% of serum samples. The viral load ranged from 2 × 102 copies per ml to 4·78 × 108 copies per ml. HEV IgM/IgG antibodies were not detected in the RNA-positive patients. Sequencing analysis of HEV showed that the virus belongs to genotype 3 (HEV GT3). CONCLUSIONS: Real-time PCR was a useful tool to estimate co-infection with HEV/HIV, even in patients with low viral loads and undetectable anti-HEV IgG and IgM antibodies. SIGNIFICANCE AND IMPACT OF THE STUDY: Hepatitis E virus genotype 3 (HEV GT3) has been associated with silent chronic hepatitis and cirrhosis in HIV-positive subjects worldwide, but there is a lack of data on this co-infection in Brazil.


Assuntos
Infecções por HIV/sangue , Anticorpos Anti-Hepatite/sangue , Vírus da Hepatite E/isolamento & purificação , Hepatite E/virologia , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Adulto , Brasil , Coinfecção/sangue , Coinfecção/virologia , Feminino , Genótipo , Infecções por HIV/virologia , Hepatite E/sangue , Vírus da Hepatite E/genética , Vírus da Hepatite E/imunologia , Vírus da Hepatite E/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase em Tempo Real , Carga Viral
5.
Lett Appl Microbiol ; 66(4): 313-320, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29330866

RESUMO

This study aimed to assess anthropogenic impact of surrounding population in the Private Reserve of Natural Heritage at Pantanal, the world's largest freshwater wetland ecosystem located in the centre of South America. Viral aetiological agents of acute gastroenteritis as rotavirus A (RVA), noroviruses, human adenoviruses, klassevirus and of hepatitis, as hepatitis A virus, were investigated in different aquatic matrices. Annual collection campaigns were carried out from 2009 to 2012, alternating dry and rainy seasons. Viral particles present in the samples were concentrated by the adsorption-elution method, with negatively charged membranes, and detected by qualitative and quantitative PCR. From a total of 43 samples at least one virus was detected in 65% (28) of them. Viruses were detected in all matrices with concentrations ranging from 2 × 102 to 8·3 × 104 genome copies per litre. A significant higher RVA frequency was observed in the dry season. Our data revealing dissemination of human enteric viruses in water matrices both inside and outside the reserve could be useful to trace faecal contamination in the environment and to minimize the risk of infection by exposure of susceptible individuals. SIGNIFICANCE AND IMPACT OF THE STUDY: This study is part of a collaborative project designed to investigate the environmental and health conditions of the Private Reserve of Natural Heritage at Pantanal, the largest seasonally flooded wetland in the world. The project aimed to promote health and quality of human and wildlife extending technical-scientific knowledge about pathogens present in the region. By assessing the occurrence of human enteric viruses in different water matrices we demonstrated the anthropogenic impact of surrounding population and pointed out the potential risk of infection by exposure of susceptible individuals.


Assuntos
Adenoviridae/isolamento & purificação , Enterovirus/isolamento & purificação , Gastroenterite/virologia , Vírus da Hepatite A/isolamento & purificação , Norovirus/isolamento & purificação , Parques Recreativos , Rotavirus/isolamento & purificação , Doenças Transmitidas pela Água/virologia , Adenoviridae/genética , Antígenos Virais , Brasil/epidemiologia , Ecossistema , Enterovirus/genética , Fezes/virologia , Água Doce/virologia , Gastroenterite/epidemiologia , Vírus da Hepatite A/genética , Humanos , Norovirus/genética , Chuva/virologia , Reação em Cadeia da Polimerase em Tempo Real , Rotavirus/genética , Estações do Ano , Microbiologia da Água , Doenças Transmitidas pela Água/epidemiologia
6.
Cells Tissues Organs ; 204(3-4): 150-163, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28803246

RESUMO

The treatment and regeneration of bone defects caused by traumatism or diseases have not been completely addressed by current therapies. Lately, advanced tools and technologies have been successfully developed for bone tissue regeneration. Functional scaffolding materials such as biopolymers and bioresorbable fillers have gained particular attention, owing to their ability to promote cell adhesion, proliferation, and extracellular matrix production, which promote new bone growth. Here, we present novel biofunctional scaffolds for bone regeneration composed of silk fibroin (SF) and ß-tricalcium phosphate (ß-TCP) and incorporating Sr, Zn, and Mn, which were successfully developed using salt-leaching followed by a freeze-drying technique. The scaffolds presented a suitable pore size, porosity, and high interconnectivity, adequate for promoting cell attachment and proliferation. The degradation behavior and compressive mechanical strengths showed that SF/ionic-doped TCP scaffolds exhibit improved characteristics for bone tissue engineering when compared with SF scaffolds alone. The in vitro bioactivity assays using a simulated body fluid showed the growth of an apatite layer. Furthermore, in vitro assays using human adipose-derived stem cells presented different effects on cell proliferation/differentiation when varying the doping agents in the biofunctional scaffolds. The incorporation of Zn into the scaffolds led to improved proliferation, while the Sr- and Mn-doped scaffolds presented higher osteogenic potential as demonstrated by DNA quantification and alkaline phosphatase activity. The combination of Sr with Zn led to an influence on cell proliferation and osteogenesis when compared with single ions. Our results indicate that biofunctional ionic-doped composite scaffolds are good candidates for further in vivo studies on bone tissue regeneration.


Assuntos
Materiais Biocompatíveis/química , Osso e Ossos/efeitos dos fármacos , Fosfatos de Cálcio/química , Fibroínas/química , Materiais Biocompatíveis/farmacologia , Fenômenos Biomecânicos , Osso e Ossos/citologia , Osso e Ossos/fisiologia , Diferenciação Celular , Fibroínas/farmacologia , Humanos , Engenharia Tecidual , Alicerces Teciduais
7.
Osteoarthritis Cartilage ; 22(9): 1271-81, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25038489

RESUMO

OBJECTIVE: To overcome current limitations of Tissue Engineering (TE) strategies, deeper comprehension on meniscus biology is required. This study aims to combine biomechanical segmental analysis of fresh human meniscus tissues and its correlation with architectural and cellular characterization. METHOD: Morphologically intact menisci, from 44 live donors were studied after division into three radial segments. Dynamic mechanical analysis (DMA) was performed at physiological-like conditions. Micro-computed tomography (CT) analysis of freeze-dried samples assessed micro-structure. Flow cytometry, histology and histomorphometry were used for cellular study and quantification. RESULTS: Anterior segments present significantly higher damping properties. Mid body fresh medial meniscus presents higher values of E' compared to lateral. Cyclic loads influence the viscoelastic behavior of menisci. By increasing the frequency leads to an increase in stiffness. Conversely, with increasing frequencies, the capacity to dissipate energy and damping properties initially decrease and then rise again. Age and gender directly correlate with higher E' and tan δ. Micro-CT analysis revealed that mean porosity was 55.5 (21.2-89.8)% and 64.7 (47.7-81.8)% for freeze-dried lateral and medial meniscus, respectively. Predominant cells are positive for CD44, CD73, CD90 and CD105, and lack CD31, CD34 and CD45 (present in smaller populations). Histomorphometry revealed that cellularity decreases from vascular zone 1 to zone 3. Anterior segments of lateral and medial meniscus have inferior cellularity as compared to mid body and posterior ones. CONCLUSION: Menisci are not uniform structures. Anterior segments have lower cellularity and higher damping. Cyclic loads influence viscoelastic characteristics. Future TE therapies should consider segmental architecture, cellularity and biomechanics of fresh tissue.


Assuntos
Meniscos Tibiais/fisiologia , Engenharia Tecidual/métodos , Adolescente , Idoso , Animais , Fenômenos Biomecânicos , Separação Celular/métodos , Elasticidade , Citometria de Fluxo , Humanos , Meniscos Tibiais/citologia , Pessoa de Meia-Idade , Porosidade , Especificidade da Espécie , Viscosidade , Suporte de Carga/fisiologia , Microtomografia por Raio-X , Adulto Jovem
8.
Ecotoxicology ; 23(9): 1814-22, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25154459

RESUMO

The natural LUFA 2.2 standard soil has been extensively used in hazard assessment of soil contaminants, combining representation with ecological relevance for accurate risk evaluation. This study revisited the water-extractable fraction of LUFA 2.2 soil, through consecutive soil wet-dry cycles and discusses implications of use as standard substrate in derivation of ecotoxicological data and toxicity thresholds. Potentially bioavailable contents of metals (177.9-888.7 µg/l) and the 16 polycyclic aromatic hydrocarbons (PAHs; 0.064-0.073 µg/l) were dependent on the number of soil wetting-drying cycles applied. Such contents were screened based on current EU guidelines for surface waters and reported toxicological benchmarks for aquatic organisms. Aqueous concentrations generally fit within recommended Environmental Quality Standards (EQS), except for Hg (0.13-0.22 µg/l; >Maximum Allowable Concentration-MAC-of 0.07 µg/l) and for the sum of benzo(g,h,i)perylene and indeno(1,2,3-cd)pyrene (0.005 µg/l; >double the Annual Average of 0.002 µg/l). Further, aqueous As, Zn, Cd, Ni and Cr concentrations exceeded 'lower benchmark' values for aquatic organisms, possibly reflecting an inadequate derivation for ecotoxicological data. In turn, PAHs in LUFA 2.2 soil aqueous extracts, whilst individually, are not likely to constitute a hazard to test biota exposed to its aqueous fractions. This study urges for potentially bioavailable fractions of reference and standard natural soils to be adequately characterized and addressed as part of the research aim, experimental approach and design, as well as the expected scope of the outcomes.


Assuntos
Poluentes do Solo/análise , Solo/normas , Ecotoxicologia/métodos , Monitoramento Ambiental , Metais/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Solo/química , Água/química
9.
Poult Sci ; 93(10): 2657-62, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25085932

RESUMO

Mycoplasma synoviae infection of hens has been associated with problems of eggshell quality called eggshell apex abnormalities (EAA). Little is known about the quality of EAA eggs from a commercial point of view, especially during their storage. The study aimed to examine the differences between EAA and normal eggs during storage under controlled conditions in 2 seasons, summer and winter, by comparing internal and external quality parameters. In a conventional egg production farm with white laying hens of varying ages in the city of Bastos, state of São Paulo, Brazil, 232 eggs were used in the summer season and 400 eggs in the winter season. Half of the eggs had EAA, and the other half were considered normal eggs for each season. The eggs were analyzed at 2, 7, 14, 21, and 28 d after being laid and stored from 24.6 to 25.8°C in summer and from 24 to 25°C in winter. There was no difference (P > 0.05) in the average egg weight between EAA and normal eggs at any studied time point, but in both seasons, the weight loss in EAA eggs was higher than in normal eggs. The losses in Haugh unit scores from the first to the last measurements were approximately 40% regardless of egg type or season of production. In comparing eggshell thickness, only the apices of the EAA eggs were thinner (P < 0.0001) than normal eggs in the summer, but in the winter, the EAA egg apices (P < 0.0001) and sides (P = 0.03) were both thinner. The presence of EAA did not affect the eggshell weight (P > 0.05) or eggshell percentage (P > 0.05). The eggshell strength of the EAA eggs was lower (P < 0.0001) than normal eggs in both the summer (16.57%) and winter (19.86%). The presence of EAA did not affect the internal quality of the egg, but was related to a greater loss of external quality and weight during storage.


Assuntos
Galinhas , Casca de Ovo/microbiologia , Ovos/análise , Armazenamento de Alimentos , Infecções por Mycoplasma/veterinária , Doenças das Aves Domésticas/microbiologia , Animais , Brasil , Ensaio de Imunoadsorção Enzimática , Infecções por Mycoplasma/microbiologia , Mycoplasma synoviae/fisiologia , Óvulo/microbiologia , Reação em Cadeia da Polimerase , Estações do Ano , Fatores de Tempo
10.
Food Microbiol ; 33(1): 114-23, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23122509

RESUMO

Mead is a traditional drink that contains 8%-18% (v/v) of ethanol, resulting from the alcoholic fermentation of diluted honey by yeasts. Mead fermentation is a time-consuming process and the quality of the final product is highly variable. Therefore, the present investigation had two main objectives: first, to determine the adequate inoculum size of two commercial wine-making strains of Saccharomyces cerevisiae for the optimisation of mead fermentation; and second, to determine if an increase in yeast pitching rates in batch fermentations altered the resulting aroma profiles. Minor differences were detected in the growth kinetics between the two strains at the lowest pitching rate. With increasing pitching rates net growth of the strain ICV D47 progressively decreased, whereas for the QA23 the increasing inoculum size had no influence on its net growth. The time required to reach the same stage of fermentation ranged from 24 to 96 h depending on the inoculum size. The final aroma composition was dependent on the yeast strain and inoculum size. Fourteen of the twenty-seven volatile compounds quantified could contribute to mead aroma and flavour because their concentrations rose above their respective thresholds. The formation of these compounds was particularly pronounced at low pitching rates, except in mead fermented by strain ICV D47, at 10(6) CFUs/mL. The esters isoamyl acetate, ethyl octanoate and ethyl hexanoate were the major powerful odourants found in the meads. The results obtained in this study demonstrate that yeast strain and inoculum size can favourably impact mead's flavour and aroma profiles.


Assuntos
Bebidas Alcoólicas/microbiologia , Saccharomyces cerevisiae/crescimento & desenvolvimento , Saccharomyces cerevisiae/metabolismo , Bebidas Alcoólicas/análise , Fermentação , Cinética , Odorantes/análise , Saccharomyces cerevisiae/química , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/metabolismo
11.
Chemosphere ; 310: 136731, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36209855

RESUMO

Multiple stage anaerobic system was found to be an effective strategy for reductive decolorization of azo dyes in the presence of sulfate. Bulk color removal (56-90%) was achieved concomitant with acidogenic activity in the 1st-stage reactor (R1), while organic matter removal (≤100%) and sulfate reduction (≤100%) occurred predominantly in the 2nd-stage reactor (R2). However, azo dye reduction mechanism and metabolic routes involved remain unclear. The involved microbial communities and conditions affecting the azo dye removal in a two-stage anaerobic digestion (AD) system were elucidated using amplicon sequencing (16S rRNA, fhs, dsrB and mcrA) and correlation analysis. Reductive decolorization was found to be co-metabolic and mainly associated with hydrogen-producing pathways. We also found evidence of the involvement of an azoreductase from Lactococcus lactis. Bacterial community in R1 was sensitive and shifted in the presence of the azo dye, while microorganisms in R2 were more protected. Higher diversity of syntrophic-acetate oxidizers, sulfate reducers and methanogens in R2 highlights the role of the 2nd-stage in organic matter and sulfate removals, and these communities might be involved in further transformations of the azo dye reduction products. The results improve our understanding on the role of different microbial communities in anaerobic treatment of azo dyes and can help in the design of better solutions for the treatment of textile effluents.


Assuntos
Compostos Azo , Microbiota , Compostos Azo/metabolismo , Reatores Biológicos/microbiologia , RNA Ribossômico 16S/genética , RNA Ribossômico 16S/metabolismo , Corantes/metabolismo , Sulfatos , Redes e Vias Metabólicas
12.
Polymers (Basel) ; 15(17)2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37688248

RESUMO

This work aimed to study the effect of the incorporation of graphene nanoplatelets (GRA 0.5% and 1% (w/w)) on the matrices of biobased polymers composed of starch-based materials (B20) and poly(butylene succinate) (PBS) using pine rosin (RES) as a compatibilizer. Three formulations were produced (B20/RES/PBS, B20/RES/PBS/GRA0.5%, and B20/RES/PBS/GRA1%), and their mechanical properties (tensile, flexural, hardness, and impact), rheological behavior, thermal properties (thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC)), chemical analysis (Fourier transform infrared-attenuated total reflectance (FTIR-ATR) spectroscopy), and contact angle were evaluated. Hardness (Shore D), tensile, and flexural moduli increased, whereas elongation at break and toughness decreased as GRA content increased. FTIR studies strongly supported the existence of interactions between polymeric matrices and the large surface area of GRA. The viscosity flow curves were well fitted to the Cross-Williams-Landel-Ferry (Cross-WLF) model, and the three formulations exhibited non-Newtonian (shear-thinning) behavior. The analysis of water contact angles indicated that the formulation surfaces have hydrophilic behavior. All the samples are thermally stable, and the results of this study can be used to optimize the application of biobased graphene-based composites for applications in injection molding industries.

13.
Environ Pollut ; 318: 120877, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36535425

RESUMO

Most studies on the biodegradation of textile azo dyes use color as parameter for measuring the efficiency of degradation. Although widely employed, spectrophotometric methods are susceptible to the interference of metabolites or degradation products from the biological treatment. We propose a method for determination of a model sulfonated azo dye (Direct Black 22, DB22) in wastewater using solid-phase extraction (SPE) and liquid chromatography - electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS). MS analysis in negative electrospray ionization mode showed DB22 as the most abundant precursor ion, corresponding to [M-3Na + H]2-, which yields two radical anions of m/z 370.1 and m/z 645 after MS/MS fragmentation by collision-induced dissociation (CID). Calibration curve presented adequate linearity and precision in the range of 120-1500 ng mL-1, and recovery and detection limit were appropriate to the typically employed working concentrations. Nevertheless, we observed that standard heating of DB22 under alkaline conditions to simulate the production of wastewater during dye-baths resulted in loss of MS/MS signal, without affecting color. Further analysis showed that DB22 undergoes hydrolysis and does not remain unaltered in solution. Alternative methods of hydrolysis evaluated resulted in no MS/MS signal as well. SPE-LC-ESI-MS/MS analysis evidenced the structural change of DB22 in aqueous solution while the dyeing-capacity was preserved. This technique has also the potential of being tailored to consider the detection of the hydrolyzed fragments of azo dyes in wastewater for appropriate quantification, but it was not the scope of the current step of this research. Color remains as a more reliable parameter for monitoring azo compounds which are unstable in aqueous solution, while a more robust and holistic method needs to be developed for the speciation of the DB22 products of thermal hydrolysis.


Assuntos
Espectrometria de Massas por Ionização por Electrospray , Águas Residuárias , Espectrometria de Massas por Ionização por Electrospray/métodos , Cromatografia Líquida , Espectrometria de Massas em Tandem/métodos , Compostos Azo/análise , Corantes/análise
14.
Polymers (Basel) ; 15(7)2023 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-37050248

RESUMO

This work aims to evaluate the influence of two starch-based materials (B16 and B20) on the moisture sorption isotherms, determined at 30, 40, and 50 °C, where B16 contains 5% (w/w) more starch than B20. Thermodynamic functions (differential enthalpy (∆Hdif), differential entropy (∆Sdif), integral enthalpy (Δhint), integral entropy (ΔSint), free Gibbs energy (∆G), and spreading pressure (φ)) were used to understand the water-binding behaviors and the energy requirements to remove the moisture content from the surface of these materials. The moisture sorption isotherms exhibited type III behavior, and the Guggenheim-Anderson-de Boer (GAB) model was the most suitable to fit the experimental moisture adsorption data. The adsorption isotherms of microparticles were enthalpy-controlled, with isokinetic temperature values of 221.45 and 279.77 K for B16 and B20, respectively, being higher than the harmonic mean temperature (312.94 K). The values of ∆G were positive (45.274 and 44.307 kJmol-1 for B16 and B20, respectively), indicating a non-spontaneous process. The spreading pressure values increased with increasing water activity (aw) for all isotherms. Higher values of ∆Hdif and ∆Sdif obtained from B16 confirmed its higher number of sorption sites available for binding with water molecules when compared to B20, making it less suitable for application in the food packaging industry.

15.
Bioact Mater ; 16: 403-417, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35415287

RESUMO

This study investigated the osteogenic performance of new brushite cements obtained from Li+-doped ß-tricalcium phosphate as a promising strategy for bone regeneration. Lithium (Li+) is a promising trace element to encourage the migration and proliferation of adipose-derived stem cells (hASCs) and the osteogenic differentiation-related gene expression, essential for osteogenesis. In-situ X-ray diffraction (XRD) and in-situ 1H nuclear magnetic resonance (1H NMR) measurements proved the precipitation of brushite, as main phase, and monetite, indicating that Li+ favored the formation of monetite under certain conditions. Li+ was detected in the remaining pore solution in significant amounts after the completion of hydration. Isothermal calorimetry results showed an accelerating effect of Li+, especially for low concentration of the setting retarder (phytic acid). A decrease of initial and final setting times with increasing amount of Li+ was detected and setting times could be well adjusted by varying the setting retarder concentration. The cements presented compressive mechanical strength within the ranges reported for cancellous bone. In vitro assays using hASCs showed normal metabolic and proliferative levels. The immunodetection and gene expression profile of osteogenic-related markers highlight the incorporation of Li+ for increasing the in vivo bone density. The osteogenic potential of Li-doped brushite cements may be recommended for further research on bone defect repair strategies.

16.
J Biomater Sci Polym Ed ; 32(15): 1966-1982, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34228590

RESUMO

The bone is a complex and dynamic structure subjected to constant stress and remodeling. Due to the worldwide incidence of bone disorders, tissue scaffolds and engineered bone tissues have emerged as solutions for bone grafting, which require sophisticated scaffolding architectures while keeping high mechanical performance. However, the conjugation of a bone-like scaffold architecture with efficient mechanical properties is still a critical challenge for biomedical applications. In this sense, the present study focused on the modulating the architecture of silk fibroin (SF) scaffolds crosslinked with horseradish peroxidase and mixed with zinc (Zn) and strontium (Sr)-doped ß-tricalcium phosphate (ZnSr.TCP) to mimic bone structures. The ZnSr.TCP-SF hydrogels were tuned by programmable ice-templating parameters, and further freeze-dried, in order to obtain 3D scaffolds with controlled pore orientation. The results showed interconnected channels in the ZnSr.TCP-SF scaffolds that mimic the porous network of the native subchondral bone matrix. The architecture of the scaffolds was characterized by microCT, showing tunable pore size according to freezing temperatures (-196 °C: ∼80.2 ± 20.5 µm; -80 °C: ∼73.1 ± 20.5 µm; -20 °C: ∼104.7 ± 33.7 µm). The swelling ratio, weight loss, and rheological properties were also assessed, revealing efficient scaffold integrity and morphology after aqueous immersion. Thus, the ZnSr.TCP-SF scaffolds made of aligned porous structure were developed as affordable candidates for future applications in clinical osteoregeneration and in vitro bone tissue modelling.


Assuntos
Fibroínas , Engenharia Tecidual , Osso e Ossos , Fosfatos de Cálcio , Gelo , Porosidade , Alicerces Teciduais
17.
Acta Biomater ; 123: 51-71, 2021 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-33454382

RESUMO

Decades of research in orthopaedics has culminated in the quest for formidable yet resorbable biomaterials using bioactive materials. Brushite cements most salient features embrace high biocompatibility, bioresorbability, osteoconductivity, self-setting characteristics, handling, and injectability properties. Such type of materials is also effectively applied as drug delivery systems. However, brushite cements possess limited mechanical strength and fast setting times. By means of incorporating bioactive ions, which are incredibly promising in directing cell fate when incorporated within biomaterials, it can yield biomaterials with superior mechanical properties. Therefore, it is a key to develop fine-tuned regenerative medicine therapeutics. A comprehensive overview of the current accomplishments of ion-doped brushite cements for bone tissue repair and regeneration is provided herein. The role of ionic substitution on the cements physicochemical properties, such as structural, setting time, hydration products, injectability, mechanical behaviour and ion release is discussed. Cell-material interactions, osteogenesis, angiogenesis, and antibacterial activity of the ion-doped cements, as well as its potential use as drug delivery carriers are also presented. STATEMENT OF SIGNIFICANCE: Ion-doped brushite cements have unbolted a new era in orthopaedics with high clinical interest to restore bone defects and facilitate the healing process, owing its outstanding bioresorbability and osteoconductive/osteoinductive features. Ion incorporation expands their application by increasing the osteogenic and neovascularization potential of the materials, as well as their mechanical performance. Recent accomplishments of brushite cements incorporating bioactive ions are overviewed. Focus was placed on the role of ions on the physicochemical and biological properties of the biomaterials, namely their structure, setting time, injectability and handling, mechanical behaviour, ion release and in vivo osteogenesis, angiogenesis and vascularization. Antibacterial activity of the cements and their potential use for delivery of drugs are also highlighted herein.


Assuntos
Cimentos Ósseos , Fosfatos de Cálcio , Cimentos Ósseos/farmacologia , Regeneração Óssea , Íons
18.
Braz J Biol ; 81(2): 499-507, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32428097

RESUMO

Increased agricultural production has been increased use of pesticides worldwide, which poses a threat to both human and environmental health. Recent studies suggest that several non-target organisms, from bees to mammals, show a wide variety of toxic effects of pesticides exposure, including impaired behavior, development and reproduction. Among mammals, bats are usually a neglected taxon among ecotoxicological studies, although they play important ecological and economical roles in forest ecosystems and agriculture through to seed dispersal and insect population control. Considering their wide variety of food habits, bats are exposed to environmental pollutants through food or water contamination, or through direct skin contact in their roosting areas. In order to better understand the risk posed by pesticides to bats populations, we compiled studies that investigated the main toxicological effects of pesticides in bats, aiming at contributing to discussion about the environmental risks associated with the use of pesticides.


Assuntos
Quirópteros , Poluentes Ambientais , Praguicidas , Agricultura , Animais , Abelhas , Ecossistema , Poluentes Ambientais/toxicidade , Praguicidas/toxicidade
19.
J Mater Chem B ; 9(20): 4211-4218, 2021 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-33998627

RESUMO

Rheumatoid arthritis (RA) is an autoimmune and chronic inflammatory disease characterized by joint inflammation. Since the inflammatory condition plays an important role in the disease process, it is important to develop and test new therapeutic approaches that specifically target and treat joint inflammation. In this study, a human 3D inflammatory cartilage-on-a-chip model was established to test the therapeutic efficacy of anti-TNFα mAb-CS/PAMAM dendrimer NPs loaded-Tyramine-Gellan Gum in the treatment of inflammation. The results showed that the proposed therapeutic approach applied to the human monocyte cell line (THP-1) and human chondrogenic primary cells (hCH) cell-based inflammation system revealed an anti-inflammatory capacity that increased over 14 days. It was also possible to observe that Coll type II was highly expressed by inflamed hCH upon the culture with anti-TNF α mAb-CS/PAMAM dendrimer NPs, indicating that the hCH cells were able maintain their biological function. The developed preclinical model allowed us to provide more robust data on the potential therapeutic effect of anti-TNF α mAb-CS/PAMAM dendrimer NPs loaded-Ty-GG hydrogel in a physiologically relevant model.


Assuntos
Anti-Inflamatórios não Esteroides/uso terapêutico , Anticorpos Monoclonais/uso terapêutico , Materiais Biocompatíveis/uso terapêutico , Dendrímeros/uso terapêutico , Dispositivos Lab-On-A-Chip , Inibidores do Fator de Necrose Tumoral/uso terapêutico , Anti-Inflamatórios não Esteroides/síntese química , Anti-Inflamatórios não Esteroides/química , Anticorpos Monoclonais/química , Artrite Reumatoide/tratamento farmacológico , Materiais Biocompatíveis/síntese química , Materiais Biocompatíveis/química , Células Cultivadas , Dendrímeros/síntese química , Dendrímeros/química , Humanos , Hidrogéis/química , Inflamação/tratamento farmacológico , Nanopartículas/química , Polissacarídeos Bacterianos/química , Inibidores do Fator de Necrose Tumoral/síntese química , Inibidores do Fator de Necrose Tumoral/química , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Tiramina/química
20.
J Mater Chem B ; 8(6): 1128-1138, 2020 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-31971528

RESUMO

Cancer nanotechnology is a prolific field of research, where nanotools are employed to diagnose and treat cancer with unprecedented precision. Targeted drug delivery is fundamental for more efficient cancer treatments. For this, nanoparticles have been extensively used during the past few years in order to improve the specificity, selectivity and controlled release of drug delivery. It holds potential in minimizing systemic toxicity through the development of functionalized particles for targeted treatment. Among all the type of nanoparticles, dendrimers display several advantages, which make them ideal candidates for improved and targeted drug delivery in cancer research. Dendrimers can transport large amounts of drug into specific areas. In addition, they can be employed for monitoring the progress of the treatment process, with an unprecedented theranostic capability. Special emphasis is given to colorectal cancer and to the preferred employed strategies for producing drug-loaded/functionalized NPs for cancer therapy in the past few years.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias do Colo/tratamento farmacológico , Dendrímeros/química , Nanopartículas/química , Animais , Antineoplásicos/química , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Humanos , Nanotecnologia
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