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1.
Braz J Biol ; 83: e272252, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37672434

RESUMO

Cerambycidae beetles limit production and establishment of forest and fruit trees. Oncideres cervina Thomson, 1868 (Coleoptera: Cerambycidae) is one of the most important species. The objective was to record O. cervina girdling branches of Persea americana Mill. (Lauraceae) for the first time, check the number of oviposition incisions (Noi) as a function of the diameter of branch sections, period of emergence, and describe the larval-pupal chamber. Individuals of O. cervina were observed, for the first time, in P. americana orchards in Santa Maria, Rio Grande do Sul, Brazil. The middle section of branches (40-60 cm interval) had higher number of incisions. Girdled branches with a diameter of 40-50 mm had higher number of them. Adults emerged from November through January. Larval-pupal boreholes had diameters between 9 and 11 mm, and average tunnel length was 28 mm, with a mean volume of consumed wood of 4.3 mL. This information is useful for establishing integrated pest management practices against O. cervina in P. americana since this crop has a high added value and can be significantly compromised by attack by Cerambycidae beetles.


Assuntos
Besouros , Lauraceae , Persea , Feminino , Animais , Larva , Brasil , Pupa
2.
Kans J Med ; 16: 117-120, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37283779

RESUMO

Introduction: The practice of repeat head CT imaging in infants as a distinct population is poorly studied. The purpose of this study was to evaluate the incidence and utility of repeat head CT in the infant population. Methods: A 10-year retrospective review was conducted of infants with blunt traumatic head injuries (N = 50) that presented to a trauma center. Information from the hospital trauma registry and patient medical records were extracted regarding the size and type of injury, number and results of computed tomography (CT) imaging, changes in neurological exams, and any interventions that were required. Results: Most patients (68%) had at least one repeat CT, with 26% showing progression of hemorrhage. Decreased Glasgow Coma Scale was associated with having repeat CT scans. Nearly one in four infants had a change in management associated with repeat imaging. Repeat CT scans resulted in operative interventions in 11.8% of cases and longer intensive care unit (ICU) stays in 8.8% of cases. Repeat CT scans were associated with increased hospital length of stay, but not with increased ventilator days, ICU length of stay, or mortality. Worsening bleeds were associated with mortality, but not with other hospital outcomes. Conclusions: Changes in management following repeat CT appeared to be more common in this population than in older children or adults. Findings from this study supported repeat CT imaging in infants, however, further research is needed to validate results of this study.

3.
Braz. j. biol ; 81(4): 969-976, Oct.-Dec. 2021. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1153452

RESUMO

Abstract Lycosa erythrognatha Lucas, 1833 (Araneae: Lycosidae) is a predatory arthropod with potential for conservation biological control. In addition to being considered a bioindicator of environmental quality, this arthropod provides an important service for agriculture by reducing insect-pest populations. In this work we seek to understand how the plants Andropogon bicornis L., Saccharum angustifolium Nees and Eustachys retusa Lag (Poales: Poaceae) and their different clump sizes affect the population density, spatial distribution and determination of the minimum number of samples to estimate its population density during the winter. Among the evaluated host plants, S. angustifolium and A. bicornis presented higher population density than E. retusa, but we observed that the clump diameter significantly influences the population density and the minimum number of samples. We observed a gregarious behavior in plants of A. bicornis and E. retusa. For S. angustifolium, a uniform distribution was observed.


Resumo Lycosa erythrognatha Lucas, 1833 (Araneae: Lycosidae) é um artrópode predador com potencial para controle biológico de conservação. Além de ser considerado um bioindicador da qualidade ambiental, esse artrópode fornece um importante serviço para a agricultura, reduzindo as populações de insetos-praga. Neste trabalho buscamos entender como as plantas Andropogon bicornis L., Saccharum angustifolium Nees e Eustachys retusa Lag (Poales: Poaceae) e seus diferentes tamanhos de touceira afetam a densidade populacional, distribuição espacial e a determinação do número mínimo de amostras para estimar sua densidade populacional durante o inverno. Entre as plantas hospedeiras avaliadas, S. angustifolium e A. bicornis apresentaram maior densidade populacional que E. retusa, observamos que o diâmetro da touceira influencia significativamente a densidade populacional e o número mínimo de amostras. Observamos um comportamento gregário nas plantas de A. bicornis e E. retusa. Para S. angustifolium, uma distribuição uniforme foi observada.


Assuntos
Animais , Aranhas , Comportamento Predatório , Densidade Demográfica , Tamanho da Amostra , Agricultura
4.
Braz J Biol ; 81(4): 969-976, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33053133

RESUMO

Lycosa erythrognatha Lucas, 1833 (Araneae: Lycosidae) is a predatory arthropod with potential for conservation biological control. In addition to being considered a bioindicator of environmental quality, this arthropod provides an important service for agriculture by reducing insect-pest populations. In this work we seek to understand how the plants Andropogon bicornis L., Saccharum angustifolium Nees and Eustachys retusa Lag (Poales: Poaceae) and their different clump sizes affect the population density, spatial distribution and determination of the minimum number of samples to estimate its population density during the winter. Among the evaluated host plants, S. angustifolium and A. bicornis presented higher population density than E. retusa, but we observed that the clump diameter significantly influences the population density and the minimum number of samples. We observed a gregarious behavior in plants of A. bicornis and E. retusa. For S. angustifolium, a uniform distribution was observed.


Assuntos
Aranhas , Agricultura , Animais , Densidade Demográfica , Comportamento Predatório , Tamanho da Amostra
5.
Neotrop Entomol ; 49(6): 806-811, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32809137

RESUMO

Stink bugs (Pentatomidae) are among the main entomological problems in the international farming. Their ability in using alternative plants (refuges) during the off-season is one of the reasons that led them to the status of key pests in several crops. Like other insect species, stink bugs are subject to atmospheric variations. Therefore, the objective of this experiment was to evaluate the abundance, the co-occurrence, and its variations according to the weather in the off-season. The work was conducted between 2014 and 2018, in the municipality of Cruz Alta, state of Rio Grande do Sul (RS), Brazil. Every year, refuges formed by Poaceae and located around the cropped area were evaluated in the second fortnight of June, corresponding to the beginning of the winter solstice. Atmospheric variables corresponding to the evaluation period were used to explain the variation in the populations. In short, our results demonstrated interannual variations in the population abundance of stink bugs in the evaluated refuges. We also found variations in the co-occurrence between species. Finally, we demonstrate the trend in the increase in these refuges in years with cold and dry off-seasons.


Assuntos
Atmosfera , Heterópteros , Tempo (Meteorologia) , Animais , Brasil , Produtos Agrícolas , Refúgio de Vida Selvagem , Estações do Ano , Glycine max
6.
Braz J Med Biol Res ; 53(2): e8962, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32022102

RESUMO

The aims of this study were to evaluate the intra- and interobserver reproducibility of manual segmentation of bone sarcomas in magnetic resonance imaging (MRI) studies and to compare manual and semiautomatic segmentation methods. This retrospective study included twelve osteosarcoma and eight Ewing sarcoma MRI studies performed prior to any therapeutic intervention. All cases were histopathologically confirmed. Three radiologists used 3D-Slicer software to perform manual segmentation of bone sarcomas in a blinded and independent manner. One radiologist segmented manually and also performed semiautomatic segmentation with the GrowCut tool. Segmentation exercises were timed for comparison. The dice similarity coefficient (DSC) and Hausdorff distance (HD) were used to evaluate similarity between the segmentation results and further statistical analyses were performed to compare DSC, HD, and volumetric results. Manual segmentation was reproducible with intraobserver DSC varying from 0.83 to 0.97 and HD from 3.37 to 28.73 mm. Interobserver DSC of manual segmentation showed variation from 0.73 to 0.97 and HD from 3.93 to 33.40 mm. Semiautomatic segmentation compared to manual segmentation resulted in DSCs of 0.71-0.96 and HDs of 5.38-31.54 mm. Semiautomatic segmentation required significantly less time compared to manual segmentation (P value ≤0.05). Among all situations compared, tumor volumetry did not show significant statistical differences (P value >0.05). We found excellent intra- and interobserver agreement for manual segmentation of osteosarcoma and Ewing sarcoma. There was high similarity between manual and semiautomatic segmentation, with a significant reduction of segmentation time using the semiautomatic method.


Assuntos
Neoplasias Ósseas/diagnóstico por imagem , Osteossarcoma/diagnóstico por imagem , Sarcoma de Ewing/diagnóstico por imagem , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Variações Dependentes do Observador , Reprodutibilidade dos Testes , Estudos Retrospectivos , Adulto Jovem
7.
Pathol Oncol Res ; 26(1): 133-139, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29270775

RESUMO

Over the last decade, the rho-associated kinases and several metastasis-associated microRNAs have emerged as important contributors of tumor invasion. However, despite prominence, our understanding of their involvement in the metastatic potential of Ewing Sarcoma (EWS) is incomplete. The expression profiles of ROCK1 or ROCK2 and miR-124-3p, miR-138-5p, miR-139-5p, miR-335-5p and miR-584-5p (all of which were previously predicted or validated to regulate these kinases) were evaluated through qRT-PCR and associated with clinical parameters. In vitro assays to evaluate colony formation and invasion/migration capacieties were performed on SK-ES-1 cells transfected with pre-miR mimics. ROCK1 expression was significantly reduced in EWS tissues, though there was no association with pathological parameters. miR-124-3p, miR-139-5p and miR-335-3p were also found significantly downregulated and positively correlated with ROCK1. Stratification indicated an association between lower levels of miR-139-5p and miR-584-5p with disease progression (p < 0.05), while reduced expression of the former and miR-124-3p were associated with reduced survival. In vitro miR-139-5p overexpression yielded inconsistent results: while mir-139-5p restoration significantly reduced invasion, the clonogenic capacity of cells was increased. Our study demonstrated that down-regulation of miR-124-3p, miR-139-5p and miR-584-5p are associated with disease progression in EWS and may serve as a risk assessment biomarkers though, as seen for mir-139-5p, their specific role remain to be elucidated for considering tailoring treatment options.


Assuntos
Neoplasias Ósseas/patologia , MicroRNAs/genética , Sarcoma de Ewing/patologia , Quinases Associadas a rho/genética , Adolescente , Adulto , Neoplasias Ósseas/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Criança , Pré-Escolar , Progressão da Doença , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Invasividade Neoplásica/genética , Sarcoma de Ewing/genética , Adulto Jovem
8.
Braz. j. med. biol. res ; 53(2): e8962, 2020. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1055495

RESUMO

The aims of this study were to evaluate the intra- and interobserver reproducibility of manual segmentation of bone sarcomas in magnetic resonance imaging (MRI) studies and to compare manual and semiautomatic segmentation methods. This retrospective study included twelve osteosarcoma and eight Ewing sarcoma MRI studies performed prior to any therapeutic intervention. All cases were histopathologically confirmed. Three radiologists used 3D-Slicer software to perform manual segmentation of bone sarcomas in a blinded and independent manner. One radiologist segmented manually and also performed semiautomatic segmentation with the GrowCut tool. Segmentation exercises were timed for comparison. The dice similarity coefficient (DSC) and Hausdorff distance (HD) were used to evaluate similarity between the segmentation results and further statistical analyses were performed to compare DSC, HD, and volumetric results. Manual segmentation was reproducible with intraobserver DSC varying from 0.83 to 0.97 and HD from 3.37 to 28.73 mm. Interobserver DSC of manual segmentation showed variation from 0.73 to 0.97 and HD from 3.93 to 33.40 mm. Semiautomatic segmentation compared to manual segmentation resulted in DSCs of 0.71−0.96 and HDs of 5.38−31.54 mm. Semiautomatic segmentation required significantly less time compared to manual segmentation (P value ≤0.05). Among all situations compared, tumor volumetry did not show significant statistical differences (P value >0.05). We found excellent intra- and interobserver agreement for manual segmentation of osteosarcoma and Ewing sarcoma. There was high similarity between manual and semiautomatic segmentation, with a significant reduction of segmentation time using the semiautomatic method.


Assuntos
Humanos , Masculino , Feminino , Pré-Escolar , Criança , Adolescente , Adulto , Adulto Jovem , Sarcoma de Ewing/diagnóstico por imagem , Neoplasias Ósseas/diagnóstico por imagem , Osteossarcoma/diagnóstico por imagem , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Variações Dependentes do Observador , Reprodutibilidade dos Testes , Estudos Retrospectivos
9.
J Dairy Sci ; 102(11): 10483-10499, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31495613

RESUMO

The aims of this work were to determine the effect of upland origin on milk composition when comparing similar lowland and upland production system and to highlight the factors responsible for the added value of upland milk from commercial farms. Tanker milk from 55 groups of farms (264 farms in total) in France, Slovakia, and Slovenia was collected twice during the indoor season and 3 times during the outdoor season. The tanker rounds were selected in each country to be balanced according to their origin (lowland or upland) and within upland or lowland groups, according to the forage systems: corn-based or grass-based forage system. At each milk sampling, the production conditions were recorded through on-farm surveys. The milk was analyzed for gross composition, carotenoids, minerals, fatty acids, phenolic compound derivatives, volatile organic compound concentrations, and color. The milk from upland and lowland areas differed in their contents of a few constituents. Upland milk was richer in not identified (n.i.) retention time (Rt) 13,59, 4-methylpentylbenzene, 1-methyl-2-n-hexylbenzene, and ß-caryophyllene than lowland milk. These differences could be most likely attributable to the utilization of highly diversified and extensively managed semi-natural grasslands. The higher forbs content of upland pastures could be related as well to the richness in C18:3n-3, CLA cis-9,trans-11, MUFA, and PUFA we observed in upland compared with lowland milk during the outdoor season. In contrast, grazing on lowland pastures rich in grasses gave a yellower milk that was richer in ß-carotene. Out of the few compounds showing a significant effect of origin or its interaction, most of the milk constituents were unaffected by the origin at all. However, almost all milk constituents differed according to the forage system and the season, and the differences observed between seasons can be attributed to differences in the cow diet composition.


Assuntos
Ração Animal/classificação , Bovinos/fisiologia , Dieta/veterinária , Leite/química , Altitude , Análise de Variância , Ração Animal/análise , Animais , Carotenoides/análise , Ácidos Graxos , Feminino , França , Lactação , Poaceae , Estações do Ano , Eslováquia , Eslovênia , Zea mays
10.
Pathol Oncol Res ; 25(1): 11-20, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28944406

RESUMO

miRNAs have been identified as key regulators of almost all cellular processes, therefore, their dysregulation is involved with several diseases, including cancer. miRNAs specifically related to the metastastic cascade are called metastamiRs and can be involved with different steps of this process, including loss of adhesion. Osteosarcoma (OS) is the most common primary malignant pediatric bone tumor that often presents metastatic disease at diagnosis; therefore, a deeper study of adhesion-associated miRNAs could shed light on its pathophysiology. Online databases were used to select four miRNAs (miR-139; miR-181b; miR-584; miR-708) predicted or validated to target proteins related to adherent junctions and focal adhesion pathways, and their expression levels and possible associations with clinical features evaluated in primary OS samples. Our results showed downregulation of miR-139-5p and miR-708-5p in OS samples compared to non-neoplastic controls. Moreover, lower expression of miR-708-5p was associated with poor overall survival and higher expression of miR-181b-5p related to worst chemotherapy response (low HUVOS level). Based on these results, we selected miR-139-5p and miR-708-5p for further functional testing. Inducing the expression of miR-139-5p diminished the clonogenic capacity of the HOS cell line, while upregulation of miR-708-5p was related to a lower cellular adhesion. In summary, this work identified new signatures of microRNA dysregulation that may serve as useful prognostic markers in this aggressive pediatric bone tumor.


Assuntos
Junções Aderentes/genética , Biomarcadores Tumorais/genética , Neoplasias Ósseas/secundário , Adesões Focais/genética , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , Osteossarcoma/patologia , Adolescente , Adulto , Neoplasias Ósseas/genética , Neoplasias Ósseas/cirurgia , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Masculino , Osteossarcoma/genética , Osteossarcoma/cirurgia , Prognóstico , Taxa de Sobrevida , Adulto Jovem
11.
Science ; 360(6389): 627-632, 2018 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-29731449

RESUMO

The precise value of the mean neutron lifetime, τn, plays an important role in nuclear and particle physics and cosmology. It is used to predict the ratio of protons to helium atoms in the primordial universe and to search for physics beyond the Standard Model of particle physics. We eliminated loss mechanisms present in previous trap experiments by levitating polarized ultracold neutrons above the surface of an asymmetric storage trap using a repulsive magnetic field gradient so that the stored neutrons do not interact with material trap walls. As a result of this approach and the use of an in situ neutron detector, the lifetime reported here [877.7 ± 0.7 (stat) +0.4/-0.2 (sys) seconds] does not require corrections larger than the quoted uncertainties.

12.
Anal Chim Acta ; 991: 58-67, 2017 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-29031299

RESUMO

Starting with an experiment to authenticate walnut oils based on GC-MS analysis of the volatolome, this paper aims to demonstrate the relevance of a two-step alignment-based strategy for the systematic research of VOC markers. The first step of the treatment consists of roughly reducing the time shifts with efficient, known warping techniques like COW (Correlation Optimized Warping). The second step relies on an accurate peak apex alignment in order to refine residual local misalignments and to enable further systematic marker research through univariate or multivariate data treatments. This two-step strategy was implemented on 117 GC-MS analyses of the volatolome of three vegetable oils with very similar composition. During the analysis campaign, the GC-MS system was intentionally subjected to instrumental drifts in order to generate realistic signal shifts. The first part of this study aims to assess the efficiency of the warping-based strategy in terms of signal alignment and sample discrimination. Whereas no distinction between the three oils was possible with unaligned raw GC-MS data, the application of COW enabled a significant but insufficient improvement of both reduction of temporal drifts and between-group separation with 79% of samples being well-classified according to Linear Discriminant Analysis (LDA). Applying the peak apex alignment procedure to COW-treated signals resulted in a suitable correction of the remaining local distortions and improved the proportion of well-classified samples in LDA to 100%. The second part of this study assesses the robustness of the discriminant markers highlighted in this approach by: (i) discussing the relevance of the best markers involved in the LDA model, where a close review of literature confirmed the consistency for two of them, and (ii) validating highlighted makers by retrieving the set of the 23 markers previously determined by manual processing among those automatically found. The third part shows the potential of the systematic approach for untargeted detection of 184 highly significant relevant markers from the oil volatolome. Finally, the fourth part presents a comparison of our hybrid alignment strategy with two reference alignment methods (iCoshift and STW) in order to assess quality alignment of the GC-MS data and to show the three methods' abilities to detect discriminant markers.


Assuntos
Análise de Alimentos/métodos , Cromatografia Gasosa-Espectrometria de Massas , Óleos de Plantas/análise , Compostos Orgânicos Voláteis/análise
13.
Bone Joint J ; 99-B(1): 139-144, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28053270

RESUMO

AIMS: Our aim was to describe the mid-term appearances of the repair process of the Achilles tendon after tenotomy in children with a clubfoot treated using the Ponseti method. PATIENTS AND METHODS: A total of 15 children (ten boys, five girls) with idiopathic clubfoot were evaluated at a mean of 6.8 years (5.4 to 8.1) after complete percutaneous division of the Achilles tendon. The contour and subjective thickness of the tendon were recorded, and superficial defects and its strength were assessed clinically. The echogenicity, texture, thickness, peritendinous irregularities and potential for deformation of the tendon were evaluated by ultrasonography. RESULTS: The appearance of the Achilles tendon was slightly abnormal, with more thickening and less conspicuous contours than a normal tendon. Its strength was grossly normal, with no insufficiency of the triceps surae. Ultrasonographic findings revealed a mild fusiform thickening in 12 children (80%). The tissue at the site of the repair had a slightly hypoechoic, fibrillar quality with hyperechoic striation and the anterior contour was irregular and blurred. There was a focal narrowing within the healing tissue in two children. CONCLUSION: This mid-term evaluation of the ability of the Achilles tendon to repair after division suggests a combination of intrinsic and extrinsic mechanisms. There were minor abnormalities which did not appear to affect function. Cite this article: Bone Joint J 2017;99-B:139-44.


Assuntos
Tendão do Calcâneo/cirurgia , Pé Torto Equinovaro/cirurgia , Tenotomia/métodos , Tendão do Calcâneo/diagnóstico por imagem , Pré-Escolar , Pé Torto Equinovaro/diagnóstico por imagem , Feminino , Seguimentos , Humanos , Masculino , Variações Dependentes do Observador , Estudos Prospectivos , Resultado do Tratamento , Ultrassonografia , Cicatrização/fisiologia
14.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1467502

RESUMO

Abstract Lycosa erythrognatha Lucas, 1833 (Araneae: Lycosidae) is a predatory arthropod with potential for conservation biological control. In addition to being considered a bioindicator of environmental quality, this arthropod provides an important service for agriculture by reducing insect-pest populations. In this work we seek to understand how the plants Andropogon bicornis L., Saccharum angustifolium Nees and Eustachys retusa Lag (Poales: Poaceae) and their different clump sizes affect the population density, spatial distribution and determination of the minimum number of samples to estimate its population density during the winter. Among the evaluated host plants, S. angustifolium and A. bicornis presented higher population density than E. retusa, but we observed that the clump diameter significantly influences the population density and the minimum number of samples. We observed a gregarious behavior in plants of A. bicornis and E. retusa. For S. angustifolium, a uniform distribution was observed.


Resumo Lycosa erythrognatha Lucas, 1833 (Araneae: Lycosidae) é um artrópode predador com potencial para controle biológico de conservação. Além de ser considerado um bioindicador da qualidade ambiental, esse artrópode fornece um importante serviço para a agricultura, reduzindo as populações de insetos-praga. Neste trabalho buscamos entender como as plantas Andropogon bicornis L., Saccharum angustifolium Nees e Eustachys retusa Lag (Poales: Poaceae) e seus diferentes tamanhos de touceira afetam a densidade populacional, distribuição espacial e a determinação do número mínimo de amostras para estimar sua densidade populacional durante o inverno. Entre as plantas hospedeiras avaliadas, S. angustifolium e A. bicornis apresentaram maior densidade populacional que E. retusa, observamos que o diâmetro da touceira influencia significativamente a densidade populacional e o número mínimo de amostras. Observamos um comportamento gregário nas plantas de A. bicornis e E. retusa. Para S. angustifolium, uma distribuição uniforme foi observada.

15.
J Mater Chem B ; 4(43): 6967-6978, 2016 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-32263563

RESUMO

Although the impact of composites based on Ti-doped calcium phosphate glasses is low compared with that of bioglass, they have been already shown to possess great potential for bone tissue engineering. Composites made of polylactic acid (PLA) and a microparticle glass of 5TiO2-44.5CaO-44.5P2O5-6Na2O (G5) molar ratio have already demonstrated in situ osteo- and angiogenesis-triggering abilities. As many of the hybrid materials currently developed usually promote osteogenesis but still lack the ability to induce vascularization, a G5/PLA combination is a cost-effective option for obtaining new instructive scaffolds. In this study, nanostructured PLA-ORMOGLASS (organically modified glass) fibers were produced by electrospinning, in order to fabricate extra-cellular matrix (ECM)-like substrates that simultaneously promote bone formation and vascularization. Physical-chemical and surface characterization and tensile tests demonstrated that the obtained scaffolds exhibited homogeneous morphology, higher hydrophilicity and enhanced mechanical properties than pure PLA. In vitro assays with rat mesenchymal stem cells (rMSCs) and rat endothelial progenitor cells (rEPCs) also showed that rMSCs attached and proliferated on the materials influenced by the calcium content in the environment. In vivo assays showed that hybrid composite PLA-ORMOGLASS fibers were able to promote the formation of blood vessels. Thus, these novel fibers are a valid option for the design of functional materials for tissue engineering applications.

16.
Nanoscale ; 7(37): 15349-61, 2015 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-26332471

RESUMO

Hybrid materials are being extensively investigated with the aim of mimicking the ECM microenvironment to develop effective solutions for bone tissue engineering. However, the common drawbacks of a hybrid material are the lack of interactions between the scaffold's constituents and the masking of its bioactive phase. Conventional hybrids often degrade in a non-homogeneous manner and the biological response is far from optimal. We have developed a novel material with strong interactions between constituents. The bioactive phase is directly exposed on its surface mimicking the structure of the ECM of bone. Here, polylactic acid electrospun fibers have been successfully and reproducibly coated with a bioactive organically modified glass (ormoglass, Si-Ca-P2 system) covalently. In comparison with the pure polymeric mats, the fibers obtained showed improved hydrophilicity and mechanical properties, bioactive ion release, exhibited a nanoroughness and enabled good cell adhesion and spreading after just one day of culture (rMSCs and rEPCs). The fibers were coated with different ormoglass compositions to tailor their surface properties (roughness, stiffness, and morphology) by modifying the experimental parameters. Knowing that cells modulate their behavior according to the exposed physical and chemical signals, the development of this instructive material is a valuable advance in the design of functional regenerative biomaterials.


Assuntos
Materiais Biocompatíveis/química , Vidro/química , Ácido Láctico/química , Nanofibras/química , Polímeros/química , Regeneração Óssea , Cálcio , Poliésteres , Propriedades de Superfície , Engenharia Tecidual , Alicerces Teciduais/química
17.
Meat Sci ; 109: 75-85, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26043665

RESUMO

In addition to microbiological issues, meat chemical safety is a growing concern for the public authorities, chain stakeholders and consumers. Meat may be contaminated by various chemical toxicants originating from the environment, treatments of agricultural production or food processing. Generally found at trace levels in meat, these toxicants may harm human health during chronic exposure. This paper overviews the key issues to be considered to ensure better control of their occurrence in meat and assessment of the related health risk. We first describe potential contaminants of meat products. Strategies to move towards a more efficient and systematic control of meat chemical safety are then presented in a second part, with a focus on emerging approaches based on toxicogenomics. The third part presents mitigation strategies to limit the impact of process-induced toxicants in meat. Finally, the last part introduces methodological advances to refine chemical risk assessment related to the occurrence of toxicants in meat by quantifying the influence of digestion on the fraction of food contaminants that may be assimilated by the human body.


Assuntos
Segurança Química , Qualidade de Produtos para o Consumidor , Contaminação de Alimentos , Indústria Alimentícia/métodos , Carne , Animais , Disponibilidade Biológica , Dieta , Poluentes Ambientais , Manipulação de Alimentos , Redução do Dano , Humanos , Medição de Risco , Toxicologia
18.
Carbohydr Polym ; 127: 372-80, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25965496

RESUMO

Cereus triangularis (Cactaceae) is a cactus used in food decoction as a traditional medicine in the North region of Madagascar to reduce stomach ache and intestinal diseases. Hydrocolloids were sequentially extracted from its cladodes with a yield of 24% (240 mg/g based on dried cladodes powder). Structural analyses has revealed that this polysaccharide with a molecular mass of 8430,000g/mol was mainly composed of a galactan backbone of a (1 → 4) linked ß-d-Galp residues probably substituted at position 3 by L-arabinofuranosyl residues. In vitro antioxidant activity of this arabinogalactan-rich fraction was detected and quantified by radical DPPH scavenging, hydroxyl radical scavenging, radical anion superoxide scavenging and reducing power method.


Assuntos
Antioxidantes/química , Cactaceae/química , Galactanos/química , Extratos Vegetais/química , Antioxidantes/isolamento & purificação , Galactanos/isolamento & purificação
19.
Zoonoses Public Health ; 62(1): 7-10, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24373212

RESUMO

Rabid bats are regularly reported in Europe, especially in countries that have implemented a bat surveillance network. In May 2013, bat rabies was evidenced for the first time in Luxembourg (southern city of Differdange). The rabies virus, an EBLV-1b strain, was diagnosed in a serotine bat that bit a 29-year-old male person while he was asleep. The man received rapidly a post-exposure RABV treatment and was put under strict medical supervision.


Assuntos
Mordeduras e Picadas/virologia , Quirópteros/virologia , Lyssavirus/isolamento & purificação , Raiva/transmissão , Adulto , Animais , Bases de Dados de Ácidos Nucleicos , Europa (Continente) , Humanos , Luxemburgo , Lyssavirus/genética , Masculino , Dados de Sequência Molecular , Raiva/prevenção & controle , Vacina Antirrábica/administração & dosagem , Vírus da Raiva/genética , Vírus da Raiva/isolamento & purificação , Reação em Cadeia da Polimerase em Tempo Real , Infecções por Rhabdoviridae , Análise de Sequência
20.
Nanotechnology ; 24(25): 255305, 2013 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-23727615

RESUMO

We report on the development of micro/nanofabrication processes to create hierarchical surface topographies that expand from 50 nm to microns in size on different materials. Three different approaches (named FIB1, FIB2, and EBL) that combine a variety of techniques such as photolithography, reactive ion etching, focused ion beam lithography, electron beam lithography, and soft lithography were developed, each one providing different advantages and disadvantages. The EBL approach was employed to fabricate substrates comprising channels with features between 200 nm and 10 µm in size on polymethylmethacrylate (PMMA), which were then used to investigate the independent or competitive effects of micro- and nanotopographies on cell adhesion and morphology. Rat mesenchymal stem cells (rMSCs) were cultured on four different substrates including 10 µm wide and 500 nm deep channels separated by 10 µm distances (MICRO), 200 nm wide and 100 nm deep nanochannels separated by 200 nm distances (NANO), their combination in parallel (PARAL), and in a perpendicular direction (PERP). Rat MSCs behaved differently on all tested substrates with a high degree of alignment (as measured by both number of aligned cells and average angle) on both NANO and MICRO. Furthermore, cells exhibited the highest level of alignment on PARAL, suggesting a synergetic effect of the two scales of topographies. On the other hand, cells on PERP exhibited the lowest alignment and a consistent change in morphology over time that seemed to be the result of interactions with both micro- and nanochannels positioned in the perpendicular direction, also suggesting a competitive effect of the topographies.


Assuntos
Materiais Biocompatíveis/química , Células-Tronco Mesenquimais/citologia , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Animais , Adesão Celular , Movimento Celular , Células Cultivadas , Nanotecnologia/métodos , Polimetil Metacrilato/química , Ratos , Silício/química , Propriedades de Superfície
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