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1.
Food Res Int ; 170: 113010, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37316077

RESUMO

Dysphagia is a condition that affects the ability to chew and swallow food and beverages, having a major impact on people's health and wellbeing. This work developed gel systems with a customized texture suitable for intake by dysphagic people using 3D printing and milk. Gels were developed using skim powdered milk, cassava starch (native and modified by the Dry Heating Treatment (DHT)), and different concentrations of kappa-carrageenan (ĸC). The gels were evaluated in relation to the starch modification process and concentration of gelling agents, 3D printing performance, and suitability for dysphagic people (following both the standard fork test described by the International Dysphagia Diet Standardization Initiative (IDDSI), and also using a new device coupled to a texture analyzer). Moreover, the best formulations were evaluated for mineral bioaccessibility through simulated gastrointestinal digestion based on INFOGEST 2.0 standardized method. The results showed that ĸC had a dominant effect compared to the DHT-modified starch on gel texture, 3D printing performance, and fork tests. The gels obtained by molding or 3D printing resulted in different behaviors during the fork test, which was associated with the gel extrusion process that breaks down their initial structure. The strategies applied to tailor the texture of the milk did not affect the mineral bioaccessibility, which was kept high (>80%).


Assuntos
Transtornos de Deglutição , Leite , Humanos , Animais , Amido , Carragenina , Géis , Minerais , Impressão Tridimensional
2.
Mol Psychiatry ; 27(5): 2457-2469, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35256745

RESUMO

Mutations linked to neurodevelopmental disorders, such as intellectual disability (ID), are frequently found in genes that encode for proteins of the excitatory synapse. Transmembrane AMPA receptor regulatory proteins (TARPs) are AMPA receptor auxiliary proteins that regulate crucial aspects of receptor function. Here, we investigate a mutant form of the TARP family member stargazin, described in an ID patient. Molecular dynamics analyses predicted that the ID-associated stargazin variant, V143L, weakens the overall interface of the AMPAR:stargazin complex and impairs the stability of the complex. Knock-in mice harboring the V143L stargazin mutation manifest cognitive and social deficits and hippocampal synaptic transmission defects, resembling phenotypes displayed by ID patients. In the hippocampus of stargazin V143L mice, CA1 neurons show impaired spine maturation, abnormal synaptic transmission and long-term potentiation specifically in basal dendrites, and synaptic ultrastructural alterations. These data suggest a causal role for mutated stargazin in the pathogenesis of ID and unveil a new role for stargazin in the development and function of hippocampal synapses.


Assuntos
Canais de Cálcio , Deficiência Intelectual , Receptores de AMPA , Animais , Canais de Cálcio/genética , Canais de Cálcio/metabolismo , Hipocampo/metabolismo , Humanos , Deficiência Intelectual/genética , Deficiência Intelectual/metabolismo , Camundongos , Mutação/genética , Receptores de AMPA/genética , Receptores de AMPA/metabolismo , Sinapses/metabolismo , Transmissão Sináptica/genética
3.
Sci Rep ; 10(1): 1276, 2020 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-31992781

RESUMO

Tuning of magnetization or electrical polarization using external fields other than their corresponding conjugate fields (i.e., magnetic field for the former or electric field for the latter response) attracts renewed interest due to its potential for applications. The magnetoelectric effect in multiferroic 1-3 composite composed of alternating magnetic and ferroelectric layers operating in linear regime consequent to external biasing fields is simulated and analysed theoretically. Two-scale homogenization procedure to arrive at the equilibrium overall physical properties of magnetoelectric multiferroic composite is formulated using variational analysis. This procedure is extended to quantify the underlying local (microscopic) electric, magnetic and elastic fields and thereby compute local distribution of stresses and strains, electrical and magnetic potentials, the electric and magnetic fields as well as the equivalent von Mises stresses. The computational model is implemented by modifying the software POSTMAT (material postprocessing). Computed local stress/strain profiles and the von Mises stresses consequent to biasing electrical and magnetic fields provide insightful information related to the magnetostriction and the ensuing electrical and magnetic polarization. Average polarization and magnetization against magnetic and electric fields respectively are computed and found to be in reasonable limits of the experimental results on similar composite systems. The homogenization model covers multiferroics and its composites regardless of crystallographic symmetry (with the caveat of assuming an ideal and semi-coherent interface connecting the constituent phases) and offer computational efficiency besides unveiling the nature of the underlying microscopic field characteristics.

4.
Comput Methods Biomech Biomed Engin ; 22(6): 567-573, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30773050

RESUMO

The combination of computational methods with 3D printing allows for the control of scaffolds microstructure. Lately, triply periodic minimal surfaces (TPMS) have been used to design porosity-controlled scaffolds for bone tissue engineering (TE). The goal of this work was to assess the mechanical properties of TPMS Gyroid structures with two porosity levels (50 and 70%). The scaffold stiffness function of porosity was determined by the asymptotic homogenisation method and confirmed by mechanical testing. Additionally, microCT analysis confirmed the quality of the printed parts. Thus, the potential of both design and manufacturing processes for bone TE applications is here demonstrated.


Assuntos
Osso e Ossos/fisiologia , Análise Numérica Assistida por Computador , Engenharia Tecidual/métodos , Alicerces Teciduais/química , Módulo de Elasticidade , Análise de Elementos Finitos , Processamento de Imagem Assistida por Computador , Porosidade , Impressão Tridimensional , Microtomografia por Raio-X
5.
Neotrop Entomol ; 48(2): 332-339, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30374736

RESUMO

Diloboderus abderus (Sturm, 1826) (Coleoptera: Melolonthidae) is a serious soil pest of corn, wheat, oat, and natural and cultivated pastures in Argentina, Paraguay, Uruguay, and southern Brazil. Despite its economic importance, the genetic diversity and population structure of D. abderus remain unknown. We sequenced a fragment of the mitochondrial gene cytochrome oxidase I region (COI), of six populations of D. abderus from the Southern Cone of America. The mtDNA marker revealed a high haplotype diversity, high pairwise FST values, and significant genetic variations among populations. No correlation was found between genetic and geographical distances, yet the most common haplotype (Dab01) was present in four out of the six populations. Analysis of molecular variance showed that most of the variation was within populations of D. abderus. Tajima's D and Fu's FS tests indicated no evidence that D. abderus populations are under recent expansion. Our results indicate that genetic-based traits will likely remain localized or spread slowly, and management strategies need to be undertaken on a small scale.


Assuntos
Besouros/genética , Genética Populacional , Filogeografia , Animais , DNA Mitocondrial/genética , Marcadores Genéticos , Variação Genética , Haplótipos , Análise de Sequência de DNA , América do Sul
6.
Sci Rep ; 8(1): 4866, 2018 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-29559656

RESUMO

Electrical control of magnetization offers an extra degree of freedom in materials possessing both electric and magnetic dipole moments. A stochastic optimization combined with homogenization is applied for the solution for maximum magnetoelectric (ME) coupling coefficient α of a laminar ME composite with the thickness and orientation of ferroelectric phase as design variables. Simulated annealing with a generalized Monte Carlo scheme is used for optimization problem. Optimal microstructure with single and poly-crystalline configurations that enhances the overall α is identified. It is found that juxtaposing a preferentially oriented ferroelectric material with a ferromagnetic ferrite into a composite would result in manifold increase in magnetoelectric coupling. The interface shear strains are found to be richly contributing to the ME coupling. The preferential orientation of the ferroelectric phase in the optimal ME composite laminate is demonstrated using the optimal pole figure analyses.

7.
Bone ; 115: 68-82, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29183784

RESUMO

AIMS/HYPOTHESIS: The discovery of osteocalcin, a protein synthetized by osteoblasts, as a hormone that has positive effects on insulin resistance, contributed to support the concept of bone as an endocrine organ. However, very little is known about the molecular pathways involved in osteocalcin improved-insulin resistance. The present study aimed to investigate the mechanisms of action of osteocalcin on insulin resistance and inflammation in obese mice and 3T3-L1 adipocytes. METHODS AND RESULTS: Lean control, saline-treated obese and uncarboxylated osteocalcin (uOC)-treated obese mice were subjected to insulin tolerance test in vivo. Blood was collect for biochemical/metabolic profile analysis; and, skeletal muscle, white adipose tissue (WAT) and bone were collected for protein (Western blotting) and mRNA (RT-qPCR) analysis. uOC effects on insulin resistance and inflammation were also investigated in 3T3-L1 adipocytes challenged with tumor necrosis factor. Osteocalcin treatment improved in vivo insulin resistance in obese mice. In WAT, osteocalcin had positive effects such as (1) WAT weight reduction; (2) upregulation of glucose transporter (GLUT) 4 protein and its mRNA (Slc2a4); (3) improved insulin-induced AKT phosphorylation; (4) downregulation of several genes involved in inflammation and inflammassome transcriptional machinery, and (5) reduction of the density of macrophage in crown-like structures (histomorphometrical analysis). Notably, in 3T3-L1 adipocytes, osteocalcin restored Slc2a4/GLUT4 content and reduced the expression of inflammatory genes after TNF-a challenge; moreover, osteocalcin treatment increased AKT phosphorylation induced by insulin. Finally, it was observed that in bone, osteocalcin improves insulin resistance by increasing insulin-induced AKT phosphorylation and reducing the expression of genes involved in bone insulin resistance, resulting in increased secretion of uncarboxylated osteocalcin in circulation. CONCLUSION: We provided some mechanisms of action for osteocalcin in the amelioration of insulin resistance in obesity: in WAT, osteocalcin improves insulin resistance by decreasing inflammation, and increasing insulin signaling and the expression of Slc2a4/GLUT4; and, in bone, osteocalcin increases the secretion of uncarboxylated osteocalcin by improving insulin resistance.


Assuntos
Tecido Adiposo Branco/fisiopatologia , Osso e Ossos/fisiopatologia , Inflamação/fisiopatologia , Resistência à Insulina/fisiologia , Obesidade/fisiopatologia , Osteocalcina/farmacologia , Células 3T3-L1 , Tecido Adiposo Branco/efeitos dos fármacos , Tecido Adiposo Branco/metabolismo , Animais , Osso e Ossos/efeitos dos fármacos , Osso e Ossos/metabolismo , Inflamação/metabolismo , Masculino , Camundongos , Obesidade/metabolismo
8.
Genet Mol Res ; 16(3)2017 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-28829894

RESUMO

We provided the first scientific record of Melanagromyza sojae (Zehntner, 1900), through molecular characterization of partial mtDNA COI gene, that confirms the occurrence of this pest in Paraguay. Previously reported in Brazil, an outbreak of larvae of M. sojae known as the soybean stem fly (SSF) that belongs to the family Agromyzidae, was also noted in soybean fields from the Canindeyú, Alto Paraná and Itapúa Departments in Paraguay. This pest is highly polyphagous, attacking various host plant species from the family Fabaceae, such as soybean and other beans. The implications of SSF detection in Paraguay are discussed in relation to the current soybean cultivation practices from this agriculturally important South American region, including Brazil.


Assuntos
Dípteros/genética , Glycine max/parasitologia , Animais , DNA Mitocondrial/química , DNA Mitocondrial/genética , Dípteros/patogenicidade , Complexo IV da Cadeia de Transporte de Elétrons/genética , Proteínas de Insetos/genética , Paraguai
9.
Eur J Gynaecol Oncol ; 38(2): 187-190, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29953777

RESUMO

The objective of this work was to show how the influence of the microenvironment in tumor cells and consequently the onset and tumor progression is becoming increasingly more evident. Cancer is the second leading cause of death in the developed world, surpassed only by heart disease and obesity, and is increasingly recognised as an oncogenic factor in the genesis of this tumor. Inflammatory me- diators related to obesity are suspected to play a role in oncogenic modification of substrates metabolism of nutrients, most patients diagnosed with breast cancer underwent chemotherapy treatment, and this may be an aggravating factor of obesity. The authors selected 49 patients with previous diagnosis of breast cancer who had undergone chemotherapy and evaluated data regarding body mass index (BMI) before and after chemotherapy. They observed that there was statistical difference of BMI of patients before and after chemotherapy with p = 0.03. Comparing the groups, a statistical difference was found between overweight and obesity grade II and overweight and obesity grade III. Patients with a diagnosis of breast cancer usually showed on average a BMI 27.84, worsening after chemotherapy to 28.64. These findings can help to accelerate the division and cell reproduction, because obesity is a risk factor for breast cancer, and weight gain seems to be a major factor after treatment and may influence the prognosis of these women.


Assuntos
Antineoplásicos/uso terapêutico , Índice de Massa Corporal , Neoplasias da Mama/complicações , Neoplasias da Mama/tratamento farmacológico , Obesidade/complicações , Adulto , Peso Corporal , Feminino , Humanos , Estudos Longitudinais , Pessoa de Meia-Idade , Sobrepeso/complicações , Estudos Prospectivos
10.
Int Rev Neurobiol ; 130: 1-40, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27678173

RESUMO

Central nervous system (CNS) diseases constitute a set of challenging pathological conditions concerning diagnosis and therapeutics. For most of these disorders, there is a lack of early diagnosis, biomarkers to allow proper follow-up of disease progression and effective therapeutic strategies to allow a persistent cure. The poor prognosis of most CNS diseases is, therefore, a global concern, especially regarding chronic age-related neurodegenerative disorders, which are already considered problems of public health due to the increasing average of life expectancy. The difficulties associated with the treatment of CNS diseases are owed, at least in part, to very specific characteristics of the brain and spinal cord, when compared to peripheral organs. In this regard, the CNS is physically and chemically protected by the blood-brain barrier (BBB), which, while maintaining essential brain homeostasis, significantly restricts the delivery of most therapeutic agents to the brain parenchyma. On the other hand, regenerative properties of the tissue are lacking, meaning that a CNS insult resulting in neuronal death is a permanent phenomenon. Approaches for transposing the BBB aiming to treat CNS diseases, relying on specific properties of nanosystems, have been reported for therapeutic delivery to CNS without interfering with the normal function of the brain. In this chapter, we address the latest advances concerning the principles of such approaches, employing lipid-based nanoparticles and cell-produced exosomes as drug and nucleic acid delivery systems, and summarize recent example of applications in the context of neurological diseases. Major achievements obtained in preclinical studies and the trends identified by these studies are emphasized to provide new prospects for further developments in this area, thus enabling us to move from the research realm to the clinical arena.


Assuntos
Doenças do Sistema Nervoso Central/tratamento farmacológico , Exossomos , Nanopartículas/uso terapêutico , Nanotecnologia/tendências , Animais , Sistemas de Liberação de Medicamentos , Humanos , Lipídeos/administração & dosagem , Nanopartículas/administração & dosagem
11.
Genet Mol Res ; 15(2)2016 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-27420989

RESUMO

Soybean Stem Fly (SSF), Melanagromyza sojae (Zehntner), belongs to the family Agromyzidae and is highly polyphagous, attacking many plant species of the family Fabaceae, including soybean and other beans. SSF is regarded as one of the most important pests in soybean fields of Asia (e.g., China, India), North East Africa (e.g., Egypt), parts of Russia, and South East Asia. Despite reports of Agromyzidae flies infesting soybean fields in Rio Grande do Sul State (Brazil) in 1983 and 2009 and periodic interceptions of SSF since the 1940s by the USA quarantine authorities, SSF has not been officially reported to have successfully established in the North and South Americas. In South America, M. sojae was recently confirmed using morphology and its complete mitochondrial DNA (mtDNA) was characterized. In the present study, we surveyed the genetic diversity of M. sojae, collected directly from soybean host plants, using partial mtDNA cytochrome oxidase I (COI) gene, and provide evidence of multiple (>10) maternal lineages in SSF populations in South America, potentially representing multiple incursion events. However, a single incursion involving multiple-female founders could not be ruled out. We identified a haplotype that was common in the fields of two Brazilian states and the individuals collected from Australia in 2013. The implications of SSF incursions in southern Brazil are discussed in relation to the current soybean agricultural practices, highlighting an urgent need for better understanding of SSF population movements in the New World, which is necessary for developing effective management options for this significant soybean pest.


Assuntos
Dípteros/genética , Polimorfismo Genético , Distribuição Animal , Animais , Brasil , Dípteros/fisiologia , Complexo IV da Cadeia de Transporte de Elétrons/genética , Efeito Fundador , Haplótipos , Proteínas de Insetos/genética
12.
Genet Mol Res ; 15(2)2016 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-27173209

RESUMO

Since its detection in Brazil in 2013, the Old World cotton bollworm Helicoverpa armigera has been reported in Argentina, Paraguay, and Bolivia. Here we present evidence extending the South American range of H. armigera to Uruguay, using polymerase chain reaction and sequencing of the partial mitochondrial DNA (mtDNA) cytochrome oxidase I region. Molecular characterization of this gene region from individuals from Paraguay also supports previous morphological identification of H. armigera in Paraguay. Shared mtDNA haplotypes in H. armigera from Brazil, Uruguay, and Paraguay were identified. Additional surveying of populations in this region will be imperative to better monitor and understand factors that are underpinning its presence and successful adaptation in these South American regions. We discuss our findings with respect to the development of resistance pest management strategies of this invasive insect pest in a predominantly monoculture soybean crop landscape in the Southern Cone region.


Assuntos
DNA Mitocondrial/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Proteínas de Insetos/genética , Lepidópteros/genética , Adaptação Fisiológica/genética , Animais , Lepidópteros/patogenicidade , Lepidópteros/fisiologia , Paraguai , Uruguai
13.
Genet Mol Res ; 15(2)2016 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-27173218

RESUMO

Genomic DNA extraction is crucial for molecular research, including diagnostic and genome characterization of different organisms. The aim of this study was to comparatively analyze protocols of DNA extraction based on cell lysis by sarcosyl, cetyltrimethylammonium bromide, and sodium dodecyl sulfate, and to determine the most efficient method applicable to soybean caterpillars. DNA was extracted from specimens of Chrysodeixis includens and Spodoptera eridania using the aforementioned three methods. DNA quantification was performed using spectrophotometry and high molecular weight DNA ladders. The purity of the extracted DNA was determined by calculating the A260/A280 ratio. Cost and time for each DNA extraction method were estimated and analyzed statistically. The amount of DNA extracted by these three methods was sufficient for PCR amplification. The sarcosyl method yielded DNA of higher purity, because it generated a clearer pellet without viscosity, and yielded high quality amplification products of the COI gene I. The sarcosyl method showed lower cost per extraction and did not differ from the other methods with respect to preparation times. Cell lysis by sarcosyl represents the best method for DNA extraction in terms of yield, quality, and cost effectiveness.


Assuntos
Fracionamento Celular/métodos , DNA/química , Spodoptera/química , Animais , Cetrimônio , Compostos de Cetrimônio/química , DNA/genética , Genes de Insetos , Reação em Cadeia da Polimerase/métodos , Dodecilsulfato de Sódio/química , Spodoptera/genética
15.
Phlebology ; 29(9): 600-7, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23864534

RESUMO

OBJECTIVE: To assess the deep vein thrombosis risk of the treatment of the small saphenous veins depending on the anatomical pattern of the veins. METHOD: A multicenter, prospective and controlled study was carried out in which small saphenous vein trunks were treated with ultrasound-guided foam sclerotherapy. The anatomical pattern (saphenopopliteal junction, perforators) was assessed by Duplex ultrasound before the treatment. All patients were systematically checked by Duplex ultrasound 8 to 30 days after the procedure to identify a potential deep vein thrombosis. RESULTS: Three hundred and thirty-one small saphenous veins were treated in 22 phlebology clinics. No proximal deep vein thrombosis occurred. Two (0.6%) medial gastrocnemius veins thrombosis occurred in symptomatic patients. Five medial gastrocnemius veins thrombosis and four cases of extension of the small saphenous vein sclerosis into the popliteal vein, which all occurred when the small saphenous vein connected directly into the popliteal vein, were identified by systematic Duplex ultrasound examination in asymptomatic patients. Medial gastrocnemius veins thrombosis were more frequent (p = 0.02) in patients with medial gastrocnemius veins perforator. A common outlet or channel between the small saphenous vein and the medial gastrocnemius veins did not increase the risk of deep vein thrombosis. CONCLUSION: Deep vein thrombosis after foam sclerotherapy of the small saphenous vein are very rare. Only 0.6% medial gastrocnemius veins thrombosis occurred in symptomatic patients. However, the anatomical pattern of the small saphenous vein should be taken into account and patients with medial gastrocnemius veins perforators and the small saphenous vein connected directly into the popliteal vein should be checked by Duplex ultrasound one or two weeks after the procedure. Recommendations based on our everyday practice and the findings of this study are suggested to prevent and treat deep vein thrombosis.


Assuntos
Veia Safena/diagnóstico por imagem , Escleroterapia/métodos , Trombose Venosa/terapia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Veia Poplítea/diagnóstico por imagem , Estudos Prospectivos , Fatores de Risco , Veia Safena/fisiopatologia , Soluções Esclerosantes/administração & dosagem , Resultado do Tratamento , Ultrassonografia Doppler Dupla , Varizes/terapia , Insuficiência Venosa/terapia , Trombose Venosa/fisiopatologia , Adulto Jovem
16.
Neotrop Entomol ; 43(3): 282-8, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27193625

RESUMO

Comparative studies on the density and diversity of white grubs community (Coleoptera: Melolonthidae) occurring in cultivated and noncultivated fields of the Planalto region of the state of Rio Grande do Sul, Brazil, are presented. Sampling was carried out in 23 municipalities during the 2009 and 2010 winter seasons. Cultivated and noncultivated fields were chosen in each locality. Melolontid larvae were collected for identification and counted to determine the population density. A mean of 12.9 larvae m(-2) were collected in cultivated areas against 10.5 larvae m(-2) in noncultivated areas. The latter were more diverse (H' = 2.52) than cultivated areas (H' = 2.26). Despite the high evenness index (J = 0.75 noncultivated and J = 0.74 cultivated), faunistic parameters indicated Cyclocephala flavipennis Arrow and Diloboderus abderus Sturm as an extremely dominant species in cultivated areas. These results showed that the population density of white grubs increases, and their community composition is affected in cultivated areas.


Assuntos
Agricultura , Besouros , Animais , Brasil , Larva , Densidade Demográfica , Estações do Ano
17.
Neotrop Entomol ; 42(3): 325-7, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23949817

RESUMO

We report five broad-nosed weevils of the tribe Naupactini, Naupactus leucoloma Boheman, Naupactus minor (Buchanan), Naupactus peregrinus (Buchanan), Naupactus tremolerasi Hustache and Pantomorus viridisquamosus (Boheman) (Coleoptera: Curculionidae) damaging soybean plants in the state of Rio Grande do Sul, Brazil. Some of these species are recorded for the first time in Brazil, and they all belong to species groups naturally distributed in the prairies of southern Brazil, Uruguay, Central Argentina and Paraguay. Three of them have been introduced, established and expanded in other countries outside South America. The five species in conjunction with other native species of Naupactini could cause severe damages to soybean crops if the root-feeding larvae attack young growing plants.


Assuntos
Glycine max/parasitologia , Gorgulhos/classificação , Gorgulhos/fisiologia , Distribuição Animal , Animais , Brasil
18.
Clin Dev Immunol ; 2013: 186872, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23762086

RESUMO

MicroRNAs (miRNAs) are an abundant class of small noncoding RNA molecules that play an important role in the regulation of gene expression at the posttranscriptional level. Due to their ability to simultaneously modulate the fate of different genes, these molecules are particularly well suited to act as key regulators during immune cell differentiation and activation, and their dysfunction can contribute to pathological conditions associated with neuroinflammation. Recent studies have addressed the role of miRNAs in the differentiation of progenitor cells into microglia and in the activation process, aiming at clarifying the origin of adult microglia cells and the contribution of the central nervous system (CNS) environment to microglia phenotype, in health and disease. Altered expression of several miRNAs has been associated with Alzheimer's disease, multiple sclerosis, and ischemic injury, hence strongly advocating the use of these small molecules as disease markers and new therapeutic targets. This review summarizes the recent advances in the field of miRNA-mediated regulation of microglia development and activation. We discuss the role of specific miRNAs in the maintenance and switching of microglia activation states and illustrate the potential of this class of nucleic acids both as biomarkers of inflammation and new therapeutic tools for the modulation of microglia behavior in the CNS.


Assuntos
Sistema Nervoso Central/imunologia , MicroRNAs/imunologia , Microglia/imunologia , Doenças Neurodegenerativas/imunologia , Biomarcadores/metabolismo , Diferenciação Celular , Sistema Nervoso Central/efeitos dos fármacos , Sistema Nervoso Central/patologia , Citocinas/genética , Citocinas/imunologia , Regulação da Expressão Gênica , Humanos , Imunidade Inata/efeitos dos fármacos , Inflamação , Ativação de Macrófagos , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Macrófagos/patologia , MicroRNAs/antagonistas & inibidores , MicroRNAs/genética , Microglia/efeitos dos fármacos , Microglia/patologia , Células-Tronco Neurais/efeitos dos fármacos , Células-Tronco Neurais/imunologia , Células-Tronco Neurais/patologia , Doenças Neurodegenerativas/tratamento farmacológico , Doenças Neurodegenerativas/genética , Doenças Neurodegenerativas/patologia , Oligonucleotídeos Antissenso/farmacologia
19.
J Biomech ; 45(6): 938-44, 2012 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-22365847

RESUMO

Porous artificial bone substitutes, especially bone scaffolds coupled with osteobiologics, have been developed as an alternative to the traditional bone grafts. The bone scaffold should have a set of properties to provide mechanical support and simultaneously promote tissue regeneration. Among these properties, scaffold permeability is a determinant factor as it plays a major role in the ability for cells to penetrate the porous media and for nutrients to diffuse. Thus, the aim of this work is to characterize the permeability of the scaffold microstructure, using both computational and experimental methods. Computationally, permeability was estimated by homogenization methods applied to the problem of a fluid flow through a porous media. These homogenized permeability properties are compared with those obtained experimentally. For this purpose a simple experimental setup was used to test scaffolds built using Solid Free Form techniques. The obtained results show a linear correlation between the computational and the experimental permeability. Also, this study showed that permeability encompasses the influence of both porosity and pore size on mass transport, thus indicating its importance as a design parameter. This work indicates that the mathematical approach used to determine permeability may be useful as a scaffold design tool.


Assuntos
Substitutos Ósseos , Simulação por Computador , Engenharia Tecidual/métodos , Alicerces Teciduais , Transporte Biológico , Humanos , Teste de Materiais/métodos , Permeabilidade , Porosidade
20.
Neotrop Entomol ; 41(3): 252-3, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23950052

RESUMO

Observations on the bioecology and damage of Teratopactus nodicollis Boheman on Phaseolus vulgaris were carried out on field samples by assessing the number of larvae and root damage in 40 ha of a dry bean field from the Federal District, Brazil (16°4'28.41"W; 47°30'21.13"S). Larvae caused the greatest damage at the stage of germination, emergence, and primary leaves, producing 50 % stand reduction. Most larvae pupated in August and September, and adult emergence occurred in middle October. Some larvae were infected with the fungus Metarhizium spp., a biological agent that would be naturally controlling this insect.


Assuntos
Phaseolus/parasitologia , Gorgulhos/fisiologia , Animais , Larva/fisiologia
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