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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.

3.
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.

4.
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.

5.
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
6.
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
7.
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.

8.
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
9.
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
10.
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
11.
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
12.
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
13.
Braz. j. biol ; 81(2): 499-507, 2021. tab, graf, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1153369

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.


O aumento da produção agrícola tem levado ao aumento do uso de pesticidas em todo o mundo, o que representa uma ameaça para a saúde humana e ambiental. Estudos recentes sugerem que vários organismos não-alvo, de abelhas a mamíferos, apresentam uma grande variedade de efeitos tóxicos após a exposição aos pesticidas a pesticidas, incluindo alterações de comportamento, no desenvolvimento e na reprodução. Entre os mamíferos, os morcegos geralmente são negligenciados entre os estudos ecotoxicológicos, embora desempenhem importantes papéis ecológicos e econômicos nos ecossistemas florestais e na agricultura por meio do controle de dispersão de sementes e de populações de insetos. Considerando sua ampla variedade de hábitos alimentares, eles estão expostos a poluentes ambientais através da contaminação de alimentos ou água, ou através do contato direto com a pele em suas áreas de descanso. Para entender melhor o risco que os agrotóxicos representam para as populações de morcegos, compilamos estudos que investigaram os principais efeitos toxicológicos de agrotóxicos em morcegos, visando à discussão sobre os riscos ambientais associados ao uso de agrotóxicos.


Assuntos
Animais , Praguicidas/toxicidade , Piretrinas/análise , Quirópteros/fisiologia , Poluentes Ambientais/toxicidade , Inseticidas Organoclorados/análise , Abelhas , Ecossistema , Agricultura , Bioacumulação
14.
Arq. bras. med. vet. zootec. (Online) ; 72(5): 1965-1970, Sept.-Oct. 2020. tab, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1131550

RESUMO

This study aimed to describe the main behaviors of white-lipped peccaries (Tayassu pecari) expressed in a semi-intensive production system in Brazil. The behavioral activities of two groups of peccaries allocated in two paddocks were assessed, totaling 17 adult animals and eventual pups in different developmental stages. The animals were visually observed using the ad libitum sampling and scan sample methods during the adaptation and experimental phases, respectively. The animals were evaluated in the morning, afternoon, and at night. The behavioral activities observed by ad libitum sampling comprised feeding, pool contact, moving, staying inside the handling area, resting, mud bathing, mutual rubbing, rubbing, aggression, sexual behavior, copulation, foraging, breastfeeding, sleeping, territorial marking, interactions, birthing, gnawing, and other behaviors. All behaviors observed by the ad libitum sampling method were confirmed in the experimental period by scan sample, except for territorial marking and birthing. The effects of time of day were statistically significant (p <0.05) for eating, pool contact, movement, staying inside the handling area, resting, mud bathing and sleeping. These results contribute to the understanding of instinctive animal habits and to the development of nutritional, environmental and health management protocols that meet the requirements of peccaries.(AU)


Objetivou-se descrever os principais comportamentos que os queixadas (Tayassu pecari) expressam em sistema de produção semi-intensivo no Brasil, bem como suas diferenças de frequências comportamentais em função do período do dia. Foram avaliadas as atividades comportamentais de dois grupos de queixadas alocados em dois piquetes, totalizando 17 animais adultos e eventuais filhotes em diferentes estágios comportamentais. Na fase adaptativa e experimental os animais foram observados visualmente pelos métodos ad libitum e scan sample, respectivamente. Os animais foram avaliados nos períodos da manhã, tarde e noite. As atividades comportamentais observadas pelo método ad libitum foram alimentação, contato com a piscina, movimentação, interior do brete de manejo, descanso, lameando, esfregação mútua, esfregar-se, agressão, comportamento sexual, cópula, fuçando, amamentação, dormindo, marcando território, interações, manilha, parição, roendo e outros comportamentos. Todos os comportamentos observados pelo método ad libitum foram confirmados no período experimental scan sample, exceto para as variáveis marcando território e parição. O efeito do período do dia foi estatisticamente significativo (P<0,05) sobre as frequências dos comportamentos alimentação, contato com a piscina, movimentação, interior do brete de manejo, descanso, lameando e dormindo. Os resultados contribuem para a compreensão dos hábitos instintivos dos animais e, com isso, colaborar com a elaboração de protocolos de manejo nutricional, ambiental e sanitário, buscando-se suprir as necessidades dos queixadas. Futuras pesquisas envolvendo queixadas em cativeiro fomentarão os estudos voltados aos aspectos biológicos, conservacionistas e produtivos.(AU)


Assuntos
Animais , Artiodáctilos , Comportamento Animal , Bem-Estar do Animal , Brasil , Distribuição Temporal , Animais Selvagens
15.
J Mech Behav Biomed Mater ; 112: 103997, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32836095

RESUMO

Bone is a dynamic tissue with an amazing but yet limited capacity of self-healing. Bone is the second most transplanted tissue in the world and there is a huge need for bone grafts and substitutes which lead to a decrease in bone banks donors. In this study, we developed three-dimensional scaffolds based on Ti6Al4V, ZrO2 and PEEK targeting bone tissue engineering applications. Experimental mechanical compressive tests and finite element analyses were carried out to study the mechanical performance of the scaffolds. Overall, the scaffolds presented different hydrophilicity properties and a reduced elastic modulus when compared with the corresponding solid materials which can in some extension minimize the phenomenon of stress shielding. The ability as a scaffold material for bone tissue regeneration applications was evaluated in vitro by seeding human osteosarcoma (SaOS-2) cells onto the scaffolds. Then, the successful culture of SaOS-2 cells on developed scaffolds was monitored by assessment of cell's viability, proliferation and alkaline phosphatase (ALP) activity up to 14 days of culturing. The in vitro results revealed that Ti6Al4V, ZrO2 and PEEK scaffolds were cytocompatible allowing the successful culture of an osteoblastic cell line, suggesting their potential application in bone tissue engineering. Statement of Significance. The work presented is timely and relevant since it gathers both the mechanical and cellular study of non-degradable cellular structures with the potential to be used as bone scaffolds. This work allow to investigate three possible bone scaffolds solutions which exhibit a significantly reduced elastic modulus when compared with conventional solid materials. While it is generally accepted that the Ti6Al4V, ZrO2 and PEEK are candidates for such applications a further study of their features and their comparison is extremely important for a better understanding of their potential.


Assuntos
Regeneração Óssea , Engenharia Tecidual , Alicerces Teciduais , Osso e Ossos , Proliferação de Células , Módulo de Elasticidade , Humanos , Porosidade
16.
Arq. bras. med. vet. zootec. (Online) ; 72(2): 615-622, Mar./Apr. 2020. tab
Artigo em Português | LILACS, VETINDEX | ID: biblio-1128492

RESUMO

A fabricação de queijo coalho artesanal elaborado com leite de cabra é composta pelas etapas de obtenção do leite, refrigeração, manipulação e armazenamento, que aumentam o risco de contaminação do produto. Objetivou-se neste estudo avaliar o nível de contaminação por Staphylococcus aureus em amostras de queijo coalho artesanal produzido com leite de cabra cru no estado de Pernambuco, Brasil, bem como avaliar a concordância entre a técnica oficial da Instrução Normativa nº62/2003 (Mapa) e a técnica molecular (gene nuc) para identificar S. aureus no queijo. Houve crescimento de colônias típicas de Staphylococcus aureus em 100% das amostras, e a contagem variou de 7,0×103 a 8,6×106 UFC/g. Das 30 amostras analisadas, 18 (60,0%) apresentaram valores superiores ou iguais a 105UFC/g, e 21 (70,0%) estavam contaminadas por S. aureus. A concordância entre os métodos de diagnóstico de S. aureus em queijo coalho caprino foi moderada. O nível de contaminação dos queijos revela a necessidade de ações de melhoria das condições de elaboração do produto, a fim de garantir um produto seguro aos consumidores.(AU)


The manufacture of artisanal Coalho cheese made from goat's milk is composed of the steps of obtaining milk, refrigeration, handling and storage that increase the risk of product contamination. The objective of this study was to evaluate the level of contamination by Staphylococcus aureus in samples of artisanal Coalho cheese produced with raw goat's milk in the state of Pernambuco, Brazil. In addition to evaluating the agreement between the official technique of Normative Instruction nº62/2003 (MAPA) and the molecular technique (nuc gene) to identify S. aureus in cheese. There was growth of typical Staphylococcus aureus colonies in 100% of the samples and the count ranged from 7.0×103 to 8.6×106 CFU/g. Of the 30 analyzed samples, 18 (60.0%) presented values greater than or equal to 105CFU/g and 21 (70.0%) were contaminated by S. aureus. The agreement between the diagnostic methods of S. aureus in goat cheese was moderate. The level of contamination of cheeses reveals the need for actions to improve the preparation conditions of the product in order to guarantee a safe product to consumers.(AU)


Assuntos
Staphylococcus aureus/isolamento & purificação , Queijo/microbiologia , Leite/microbiologia , Refrigeração , Brasil , Cabras , Doenças Transmitidas por Alimentos
17.
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
18.
Arq. bras. med. vet. zootec. (Online) ; 72(1): 233-242, Jan.-Feb. 2020. tab
Artigo em Português | LILACS, VETINDEX | ID: biblio-1088935

RESUMO

O objetivo do presente estudo foi avaliar o desempenho zootécnico, os parâmetrosmorfométricos, o comportamento social, a viabilidade econômica e a análise microbiológica da água de cultivo e de tecidos corpóreos de Betta splendens alimentados com folha da amendoeira Terminalia catappa (FFDA) como aditivo. Foram utilizados 28 machos de Bettas, acondicionados individualmente em aquários de 1,5L, por 50 dias. O experimento foi realizado em delineamento experimental inteiramente ao acaso, com quatro tratamentos: 0,00%; 0,25%; 0,50% e 0,75% de inclusão da FFAD e sete repetições. Ao término do experimento, foram avaliados os parâmetros: desempenho zootécnico (ganho de peso diário, consumo de ração, conversão alimentar aparente, taxa de eficiência proteica, taxa de crescimento específico e fator de condição), morfométrico (comprimento total, padrão e da cabeça, altura, índice de perfil e índice de cabeça), comportamento social, viabilidade econômica da ração, análise microbiana do conteúdo intestinal, filé e escama e análise microbiológica da água. Pela ANOVA, pelo teste de Tukey e pela regressão (P>0,05), os parâmetros: peso final, ganho de peso, comprimento padrão, comprimento total e taxa de crescimento específico foram influenciados pelos tratamentos (P<0,05), apresentando um efeito quadrático. Assim, recomenda-se o nível de 0,50% de Terminalia catappa como aditivo em dietas de Betta splendens.(AU)


The objective of this study was to evaluate the performance, morphometric parameters, social behavior, economic viability, the presence of enterobacteria in the intestinal contents and a microbiological analysis of the water culture of Betta splendens fed with almond-tree-leaf flour (ATLF) as an additive. Twenty-eight male B. splendens were individually put in 1.5 L aquariums. The experiment was done in a completely randomized experimental design with four treatments: 0.00%; 0.25%; 0.50% and 0.75%, of the ATLF, dehydrated Terminalia catappa with seven repetitions each. At the end of the experimental period, the parameters were evaluated: performance (daily weight gain, feed intake, apparent feed conversion, protein efficiency rate, specific growth rate and condition factor), morphometric (total length, standard head, height, profile index and head index), social behavior, economic viability of the feed, microbial analysis of intestinal contents, fillet and scales, and microbiological analysis of the water. Though ANAVA, Tukey test and regression analysis (P> 0.05), the parameters: final weight, weight gain, standard length, total length and specific growth rate were influenced by the treatments (P< 0.05), presenting a quadratic effect. Therefore, the 0.50% level of Terminalia catappa is recommended as additive in Betta splendens diets.(AU)


Assuntos
Animais , Perciformes/crescimento & desenvolvimento , Terminalia , Prebióticos/administração & dosagem
19.
J Mech Behav Biomed Mater ; 102: 103516, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31877521

RESUMO

The present study aims at developing a computational framework with experimental validation to determine the mechanical properties of zirconia foams for bone tissue engineering. A micro-CT based finite element model that allows characterizing the mechanical property of such cellular structures is developed. Micro-CT images are filtered to vanish noises and smooth boundaries before constructing 3D zirconia foams using an adaptive Body-Centered Cubic background lattice. In addition to micro-CT images, the local material property at the scaffold struts is measured using a micro-indentation test, which shows a considerable difference with that of common zirconia owing to the manufacturing process. The computational model also takes the plastic deformation of material into account employing the Voce law, a nonlinear isotropic hardening law, as well as Von-mises yield criterion. Zirconia foams with different pore sizes are manufactured using the replica method and their mechanical properties determined experimentally. Such experimental outcomes are to validate and demonstrate the capability of the developed model, which can be used for pre-operational evaluations and preclinical tests of zirconia scaffolds. The stress magnitude and distribution within the scaffold as well as plastic strains and flow stress of the zirconia scaffold are computed and analysed. Using the proposed approach, a deep insight into the association of macroscopic behaviour of the scaffold to microscopic features, e.g. strut waviness, Plateau border, thickness variation of cells, irregularity, microstructural variability, imperfections and strut's material property associated with to the manufacturing procedure, can be gained.


Assuntos
Osso e Ossos , Engenharia Tecidual , Análise de Elementos Finitos , Estresse Mecânico , Alicerces Teciduais , Microtomografia por Raio-X , Zircônio
20.
Int J Biol Macromol ; 153: 1328-1334, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-31730995

RESUMO

Mineralization is a natural process leading to the formation of mineralized tissue such as bone. The chief mineral component of bone is hydroxyapatite (HAp), which is deposited using an organic template like fibrillar Collagen I under physiological condition. Fibrous silk fibroin is structurally homologous to collagen and acts as nucleation site for HAp mineralization when immersed in simulated body fluid (SBF) or fetal bovine serum (FBS), therefore, considered as popular bone regeneration biomaterial. Hence, the mineralization behavior of silk fibroin self-assembled gellan gum enriched 3D hydrogels is investigated under conditions closer to physiological ones using SBF as well as FBS, and also in presence of cells (e.g. human adipose tissue-derived stem cells, ASCs). Incorporation of silk fibroin induces the mineralization in acellular spongy-like hydrogels in composition dependent manner, confirmed by SEM-EDS analysis. In contrast, ASCs mediated mineralization is found in all hydrogel compositions of 3 weeks post-culture under osteogenic conditions as demonstrated by gene expression profile and Alizarin Red S staining. This is perhaps due to the co-existence of fibroin and FBS together induce cell-mediated mineralization. The blending of fibroin offers cheap alternative strategy to improve or guide the repair of mineralized tissue using gellan gum-based biomaterials.


Assuntos
Calcificação Fisiológica/efeitos dos fármacos , Fibroínas/química , Fibroínas/farmacologia , Hidrogéis/química , Polissacarídeos Bacterianos/química , Tecido Adiposo/citologia , Diferenciação Celular/efeitos dos fármacos , Humanos , Osteogênese/efeitos dos fármacos , Células-Tronco/citologia , Células-Tronco/efeitos dos fármacos
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