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The evidence- and consensus-based guideline on atopic eczema was developed in accordance with the EuroGuiDerm Guideline and Consensus Statement Development Manual. Four consensus conferences were held between December 2020 and July 2021. Twenty-nine experts (including clinicians and patient representatives) from 12 European countries participated. This second part of the guideline includes recommendations and detailed information on basic therapy with emollients and moisturizers, topical anti-inflammatory treatment, antimicrobial and antipruritic treatment and UV phototherapy. Furthermore, this part of the guideline covers techniques for avoiding provocation factors, as well as dietary interventions, immunotherapy, complementary medicine and educational interventions for patients with atopic eczema and deals with occupational and psychodermatological aspects of the disease. It also contains guidance on treatment for paediatric and adolescent patients and pregnant or breastfeeding women, as well as considerations for patients who want to have a child. A chapter on the patient perspective is also provided. The first part of the guideline, published separately, contains recommendations and guidance on systemic treatment with conventional immunosuppressive drugs, biologics and janus kinase (JAK) inhibitors, as well as information on the scope and purpose of the guideline, and a section on guideline methodology.
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Anti-Infecciosos , Produtos Biológicos , Dermatite Atópica , Fármacos Dermatológicos , Eczema , Adolescente , Anti-Infecciosos/uso terapêutico , Anti-Inflamatórios/uso terapêutico , Antipruriginosos/uso terapêutico , Produtos Biológicos/uso terapêutico , Criança , Dermatite Atópica/tratamento farmacológico , Fármacos Dermatológicos/uso terapêutico , Eczema/tratamento farmacológico , Emolientes/uso terapêutico , Feminino , Humanos , Janus QuinasesRESUMO
The evidence- and consensus-based guideline on atopic eczema was developed in accordance with the EuroGuiDerm Guideline and Consensus Statement Development Manual. Four consensus conferences were held between December 2020 and July 2021. Twenty-nine experts (including clinicians and patient representatives) from 12 European countries participated. This first part of the guideline includes general information on its scope and purpose, the health questions covered, target users and a methods section. It also provides guidance on which patients should be treated with systemic therapies, as well as recommendations and detailed information on each systemic drug. The systemic treatment options discussed in the guideline comprise conventional immunosuppressive drugs (azathioprine, ciclosporin, glucocorticosteroids, methotrexate and mycophenolate mofetil), biologics (dupilumab, lebrikizumab, nemolizumab, omalizumab and tralokinumab) and janus kinase inhibitors (abrocitinib, baricitinib and upadacitinib). Part two of the guideline will address avoidance of provocation factors, dietary interventions, immunotherapy, complementary medicine, educational interventions, occupational and psychodermatological aspects, patient perspective and considerations for paediatric, adolescent, pregnant and breastfeeding patients.
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Dermatite Atópica , Eczema , Adolescente , Azatioprina/uso terapêutico , Criança , Ciclosporina/uso terapêutico , Dermatite Atópica/tratamento farmacológico , Eczema/tratamento farmacológico , Humanos , Imunossupressores/uso terapêutico , Ácido Micofenólico/uso terapêuticoRESUMO
This evidence- and consensus-based guideline on the treatment of psoriasis vulgaris was developed following the EuroGuiDerm Guideline and Consensus Statement Development Manual. The second part of the guideline provides guidance for specific clinical and comorbid situations such as treating psoriasis vulgaris patient with concomitant psoriatic arthritis, concomitant inflammatory bowel disease, a history of malignancies or a history of depression or suicidal ideation. It further holds recommendations for concomitant diabetes, viral hepatitis, disease affecting the heart or the kidneys as well as concomitant neurological disease. Advice on how to screen for tuberculosis and recommendations on how to manage patients with a positive tuberculosis test result are given. It further covers treatment for pregnant women or patients with a wish for a child in the near future. Information on vaccination, immunogenicity and systemic treatment during the COVID-19 pandemic is also provided.
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Psoríase/complicações , Psoríase/terapia , Humanos , Psoríase/psicologiaRESUMO
This evidence- and consensus-based guideline on the treatment of psoriasis vulgaris was developed following the EuroGuiDerm Guideline and Consensus Statement Development Manual. The first part of the guideline includes general information on the scope and purpose, health questions covered, target users and strength/limitations of the guideline. Suggestions for disease severity grading and treatment goals are provided. It presents the general treatment recommendations as well as detailed management and monitoring recommendations for the individual drugs. The treatment options discussed in this guideline are as follows: acitretin, ciclosporin, fumarates, methotrexate, adalimumab, apremilast, brodalumab, certolizumab pegol, etanercept, guselkumab, infliximab, ixekizumab, risankizumab, secukinumab, tildrakizumab and ustekinumab.
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Psoríase , Adalimumab , Etanercepte , Humanos , Psoríase/tratamento farmacológico , Índice de Gravidade de Doença , UstekinumabRESUMO
Background: The role of platinum-based neoadjuvant chemotherapy in triple-negative breast cancer (TNBC) patients is highly controversial and it is not endorsed by current guidelines. Our meta-analysis aimed to better elucidate its activity, efficacy and safety. Material and methods: A systematic search of Medline, Web of Science and conferences proceedings up to 30 October 2017 was carried out to identify randomized controlled trials (RCTs) investigating platinum-based versus platinum-free neoadjuvant chemotherapy in TNBC patients. Using the fixed and random effects models, pooled odds ratios (ORs) and hazard ratios (HRs) with 95% confidence intervals (CI) were calculated for pathological complete response (pCR, defined as ypT0/is pN0), event-free survival (EFS), overall survival (OS) and grade 3 and 4 adverse events (AEs: neutropenia, anemia, thrombocytopenia and neuropathy). Results: Nine RCTs (N = 2109) were included. Overall, platinum-based neoadjuvant chemotherapy significantly increased pCR rate from 37.0% to 52.1% (OR 1.96, 95% CI 1.46-2.62, P < 0.001). Platinum-based neoadjuvant chemotherapy remained significantly associated with increased pCR rate also after restricting the analysis to the three RCTs (N = 611) that used the same standard regimen in both groups of weekly paclitaxel (with or without carboplatin) followed by anthracycline and cyclophosphamide (OR 2.53, 95% CI 1.37-4.66, P = 0.003). Conversely, among the 96 BRCA-mutated patients included in two RCTs, the addition of carboplatin was not associated with significantly increased pCR rate (OR 1.17, 95% CI 0.51-2.67, P = 0.711). Two RCTs (N = 748) reported survival outcomes: no significant difference in EFS (HR 0.72, 95% CI 0.49-1.06, P = 0.094) and OS (HR 0.86, 95% CI 0.46-1.63, P = 0.651) was observed. A significant higher risk of grade 3 and 4 hematological AEs, with no increased risk of grade 3 and 4 neuropathy was observed with platinum-based neoadjuvant chemotherapy. Conclusion: In TNBC patients, platinum-based neoadjuvant chemotherapy is associated with significantly increased pCR rates at the cost of worse hematological toxicities. Platinum-based neoadjuvant chemotherapy may be considered an option in TNBC patients. PROSPERO registration number: CRD42018080042.
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Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Terapia Neoadjuvante , Compostos Organoplatínicos/uso terapêutico , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Quimioterapia Adjuvante , Feminino , Humanos , Prognóstico , Neoplasias de Mama Triplo Negativas/patologiaRESUMO
Whole exome sequencing detected novel likely pathogenic variants in LRP2 gene in 2 patients presenting with hearing and vision loss, and the Dent disease (DD) classical renal phenotype, that is, low molecular weight proteinuria (LMWP), hypercalciuria and nephrocalcinosis/nephrolithiasis. We propose that a subset of patients presenting as DD may represent unrecognized cases or mild forms of Donnai-Barrow/facio-oculo-acustico-renal (DB/FOAR) syndrome or be on the phenotypic continuum between the 2 conditions.
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Agenesia do Corpo Caloso/diagnóstico , Perda Auditiva Neurossensorial/diagnóstico , Hérnias Diafragmáticas Congênitas/diagnóstico , Hipercalciúria/diagnóstico , Miopia/diagnóstico , Nefrolitíase/diagnóstico , Fenótipo , Proteinúria/diagnóstico , Erros Inatos do Transporte Tubular Renal/diagnóstico , Adolescente , Idoso , Agenesia do Corpo Caloso/genética , Alelos , Diagnóstico Diferencial , Estudos de Associação Genética , Predisposição Genética para Doença , Perda Auditiva Neurossensorial/genética , Hérnias Diafragmáticas Congênitas/genética , Humanos , Hipercalciúria/genética , Proteína-2 Relacionada a Receptor de Lipoproteína de Baixa Densidade/genética , Masculino , Miopia/genética , Nefrolitíase/genética , Proteinúria/genética , Erros Inatos do Transporte Tubular Renal/genéticaRESUMO
PURPOSE: The diagnostic, therapeutic and health-care management protocol (Protocollo Gestionale Diagnostico-Terapeutico-Assistenziale, PDTA) by the Association of the Italian Endocrine Surgery Units (U.E.C. CLUB) aims to help treat the patient in a topical, rational way that can be shared by health-care professionals. METHODS: This fourth consensus conference involved: a selected group of experts in the preliminary phase; all members, via e-mail, in the elaboration phase; all the participants of the XI National Congress of the U.E.C. CLUB held in Naples in the final phase. The following were examined: diagnostic pathway and clinical evaluation; mode of admission and waiting time; therapeutic pathway (patient preparation for surgery, surgical treatment, postoperative management, management of major complications); hospital discharge and patient information; outpatient care and follow-up. RESULTS: A clear and concise style was adopted to illustrate the reasons and scientific rationales behind behaviors and to provide health-care professionals with a guide as complete as possible on who, when, how and why to act. The protocol is meant to help the surgeon to treat the patient in a topical, rational way that can be shared by health-care professionals, but without influencing in any way the physician-patient relationship, which is based on trust and clinical judgment in each individual case. CONCLUSIONS: The PDTA in thyroid surgery approved by the fourth consensus conference (June 2015) is the official PDTA of U.E.C. CLUB.
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Atenção à Saúde/normas , Hospitalização/estatística & dados numéricos , Guias de Prática Clínica como Assunto/normas , Doenças da Glândula Tireoide/diagnóstico , Doenças da Glândula Tireoide/cirurgia , Tireoidectomia/normas , Tempo para o Tratamento/normas , Consenso , Humanos , ItáliaRESUMO
Scant information is available on the ultrasonographic appearance of different testicular tumours in the stallion. Preoperative ultrasound imaging and gross and microscopic features of a testicular teratoma in a horse is described. An asymptomatic 4 years old cryptorchid Arabian horse was admitted for orchiectomy. Combined transabdominal and inguinal ultrasound examination revealed a large complex ovoid mass, containing both solid and cystic elements with internal echoes, located dorsally to the superficial inguinal ring. Two main hypoechoic cavities divided by a linear hyperechoic septum were evident, with a hyperechoic circular structure inside the lumen of the largest one. A tumour of the undescended testis was suspected. Ultrasound findings guided a provisional diagnosis of teratoma that was confirmed by histology following surgical removal of the tumour. Due to the correspondence between ultrasonographic and morphological features, trans-abdominal ultrasonography was conclusive in the preoperative planning.
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Teratoma/veterinária , Neoplasias Testiculares/veterinária , Envelhecimento , Animais , Criptorquidismo , Virilha , Doenças dos Cavalos , Cavalos , Masculino , Testículo , UltrassonografiaRESUMO
X-ray tomography is a relevant technique for the dynamic follow-up of gas bubbles in an opaque viscoelastic matrix, especially using image analysis. It has been applied here to pieces of fermenting wheat flour dough of various compositions, at two different voxel sizes (15 and 5 µm). The resulting evolution of the main cellular features shows that the creation of cellular structures follows two regimes that are defined by a characteristic time of connectivity, tc [30 and 80 min]: first (t ≤ tc), bubbles grow freely and then (t ≥ tc) they become connected since the percolation of the gas phase is limited by liquid films. During the first regime, bubbles can be tracked and the local strain rate can be measured. Its values (10(-4)-5 × 10(-4) s(-1)) are in agreement with those computed from dough viscosity and internal gas pressure, both of which depend on the composition. For higher porosity, P = 0.64 in our case, and thus occurring in the second regime, different cellular structures are obtained and XRT images show deformed gas cells that display complex shapes. The comparison of these images with confocal laser scanning microscopy images suggests the presence of liquid films that separate these cells. The dough can therefore be seen as a three-phase medium: viscoelastic matrix/gas cell/liquid phase. The contributions of the different levels of matter organization can be integrated by defining a capillary number (C = 0.1-1) that makes it possible to predict the macroscopic dough behavior.
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Fermentação , Farinha , Gases/química , Transição de Fase , Elasticidade , Porosidade , Viscosidade , Microtomografia por Raio-XRESUMO
We identify a novel and counterintuitive regime of discrete diffraction for astigmatic light beams in 2D tight-binding photonic lattices, in which diffraction is almost inhibited along the axis with strongest localization, whereas it is enhanced along the axis with weakest localization. Furthermore, beams of these kind exhibit dichotomy wave packet splitting during propagation, and each of the two wings of the wave packet turns out to implement an Abel transformation of the initial envelope of the astigmatic beam.
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The high malignancy of glioblastoma has been recently attributed to the presence, within the tumor, of glioblastoma stem cells (GSC) poorly responsive to chemo- and radiotherapy. Here, the potential employment of metformin and arsenic trioxide (ATO) in glioblastoma therapy is discussed focusing on their effects on GSC. Metformin exerts anticancer effects by primarily blocking the pivotal LKB1/AMPK/mTOR/S6K1 pathway-dependent cell growth, induces selective lethal effects on GSC by impairing the GSC-initiating spherogenesis and inhibits the proliferation of CD133+ cells, while having a low or null effect on differentiated glioblastoma cells and normal human stem cells. Metformin and ATO induce autophagy and apoptosis in glioma cells by inhibiting and stimulating the PI3K/Akt and the mitogen-activated protein kinase pathways, respectively. Both drugs promote differentiation of GSC into non-tumorigenic cells. In this regard, metformin acts via activation of the AMPK-FOXO3 axis, whereas ATO blocks the interleukin 6-induced promotion of STAT3 phosphorylation. Blood-brain barrier, easily crossed by metformin but not by ATO, undergoes important glioblastoma-induced alterations that increase its permeability, thus allowing ATO to distribute more into the glioblastoma bulk than in the normal brain parenchyma. A prompt clinical assessment of metformin and ATO in glioblastoma patients would represent a valid attempt to improve their survival.
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Antineoplásicos/farmacologia , Arsenicais/farmacologia , Neoplasias Encefálicas/tratamento farmacológico , Glioblastoma/tratamento farmacológico , Metformina/farmacologia , Células-Tronco Neoplásicas/efeitos dos fármacos , Óxidos/farmacologia , Quinases Proteína-Quinases Ativadas por AMP , Proteínas Quinases Ativadas por AMP/antagonistas & inibidores , Animais , Trióxido de Arsênio , Neoplasias Encefálicas/patologia , Resistencia a Medicamentos Antineoplásicos , Glioblastoma/patologia , Humanos , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Tolerância a RadiaçãoRESUMO
The survival rate of mesenchymal stem cells (MSC), a crucial factor in tissue engineering, is highly dependent on glucose supply. The purpose of this paper is to study the potential of starch foams as glucose suppliers. It is investigated through in vitro hydrolysis by amyloglucosidase in conditions that respect physiological constraints (37 °C and pH 7.4), including a duration of 21 days, and no stirring. Nine extruded starch foams with amylose contents ranging from 0 to 74 %, with various cell wall thicknesses (50 to 300 µm), and different crystallinities (0-30 %) were hydrolysed. These kinetics were fitted by a model which shows that the maximum rate of hydrolysis varies from 7 to 100 %, and which allows the rate of hydrolysis at 21 days to be calculated precisely. The results reveal the major role of amylose in glucose delivery kinetics, and the secondary roles of crystallinity and cell wall thickness of the foams. Additional hydrolysis of starch films revealed that thickness positively influences the amylose chain reorganisation during hydrolysis, which, in slows down and limits glucose delivery. A simple glucose delivery kinetics analysis procedure is proposed to select samples for testing as MSC glucose suppliers.
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Amilose , Materiais Biocompatíveis , Glucose , Células-Tronco Mesenquimais , Amido , Hidrólise , Glucose/química , Amido/química , Materiais Biocompatíveis/química , Amilose/química , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/citologia , Cinética , Glucana 1,4-alfa-Glucosidase/metabolismo , Glucana 1,4-alfa-Glucosidase/químicaRESUMO
Paslahepevirus balayani genotypes 3 and 4 (HEV-3 and 4) have zoonotic potential and can be transmitted to humans and animals through the consumption of contaminated raw or undercooked meat. Although it has been demonstrated that dogs are susceptible to the infection and produce specific antibodies, the epidemiological role of this species is not yet well defined. This study aimed to evaluate the circulation of HEV at the serological and molecular level in the dog population of the Campania region, southern Italy. A total of 231 dogs were sampled, divided according to several variables (sex, age, origin, lifestyle, location, size, and breed), and tested for the presence of HEV antibodies using a commercial multi-species ELISA. A total of 197 blood samples and 170 stool samples were tested with two specific PCRs in order to detect viral RNA. A total of 19 out samples of 231 were seropositive, obtaining an exposure (8.2%) similar to that observed in other European countries. The univariate and multivariate analysis revealed a wide exposure to stray dogs and animals from the province of Salerno. All samples tested with molecular methods were negative. Defining the role of domestic carnivores continues to be a "one health" challenge, although it appears that they do not eliminate the virus and therefore do not pose a danger to humans. In the absence of other evidence, it is advisable to continue to carry out surveillance also for domestic animals, which, due to ethological characteristics or their position in the food chain, could be predisposed to being exposed to HEV.
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We introduce and experimentally demonstrate a class of surface bound states with algebraic decay in a one-dimensional tight-binding lattice. Such states have an energy embedded in the spectrum of scattered states and are structurally stable against perturbations of lattice parameters. Experimental demonstration of surface states with algebraic localization is presented in an array of evanescently coupled optical waveguides with tailored coupling rates.
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The silverleaf whitefly, Bemisia tabaci (Genn.) (Hemiptera: Aleyrodidae), is a cryptic species complex that contains some of the most damaging pests in tropical and subtropical regions. Recent studies have indicated that this complex is composed of at least 24 distinct and morphologically indistinguishable species that mainly differ in their ability to transmit phytoviruses, adapt to hosts, and induce physiological changes in certain hosts. The importance of this species has been increasing worldwide, because it serves as a phytovirus vector, particularly for geminiviruses, in economically important crops. Here, we aimed to examine the population variability of B. tabaci populations inhabiting 6 agricultural crops grown in 5 regions of Brazil and 1 region of the USA; BRrep [Brasília (DF, Brazil) - cabbage], ILsoj [Urbana (IL/USA) - soybean], BJabo [Bom Jesus da Lapa (BA, Brazil) - pumpkin], CPsoj [Campinas (SP, Brazil) - soybean], UBman [Ubatuba (SP, Brazil) - cassava], and PEmel [Petrolina (PE, Brazil) - melon]. Thirteen polymorphic loci with 50 alleles were observed, with an average of 2.37 (range: 2.00-2.91) alleles per population. The UBman and PEmel B. tabaci populations were the most differentiated, which was probably caused by insect adaptation to the host plant and the use of insecticides. A 33.87% inter-population variation was observed, indicating that microsatellites may be used to measure differentiation among these B. tabaci populations. Based on the comparison of microsatellites in the current study, only the Middle East-Asia Minor 1 population of B. tabaci was found in the six populations.
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Hemípteros/genética , Polimorfismo Genético , Alelos , Animais , Teorema de Bayes , Brasil , Genes de Insetos , Marcadores Genéticos , Genética Populacional , Especificidade de Hospedeiro , Insetos Vetores/genética , Repetições de Microssatélites , Modelos Genéticos , Filogenia , Doenças das Plantas/parasitologia , Doenças das Plantas/virologia , Estados UnidosRESUMO
Autosomal recessive limb-girdle muscular dystrophies (AR LGMDs) are a genetically heterogeneous group of disorders that affect mainly the proximal musculature. There are eight genetically distinct forms of AR LGMD, LGMD 2A-H (refs 2-10), and the genetic lesions underlying these forms, except for LGMD 2G and 2H, have been identified. LGMD 2A and LGMD 2B are caused by mutations in the genes encoding calpain 3 (ref. 11) and dysferlin, respectively, and are usually associated with a mild phenotype. Mutations in the genes encoding gamma-(ref. 14), alpha-(ref. 5), beta-(refs 6,7) and delta (ref. 15)-sarcoglycans are responsible for LGMD 2C to 2F, respectively. Sarcoglycans, together with sarcospan, dystroglycans, syntrophins and dystrobrevin, constitute the dystrophin-glycoprotein complex (DGC). Patients with LGMD 2C-F predominantly have a severe clinical course. The LGMD 2G locus maps to a 3-cM interval in 17q11-12 in two Brazilian families with a relatively mild form of AR LGMD (ref. 9). To positionally clone the LGMD 2G gene, we constructed a physical map of the 17q11-12 region and refined its localization to an interval of 1.2 Mb. The gene encoding telethonin, a sarcomeric protein, lies within this candidate region. We have found that mutations in the telethonin gene cause LGMD 2G, identifying a new molecular mechanism for AR LGMD.
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Cromossomos Humanos Par 17 , Proteínas Musculares/genética , Distrofias Musculares/genética , Sequência de Aminoácidos , Sequência de Bases , Mapeamento Cromossômico , Conectina , Éxons , Feminino , Genes Recessivos , Marcadores Genéticos , Humanos , Íntrons , Masculino , Repetições de Microssatélites , Dados de Sequência Molecular , Proteínas Musculares/química , Distrofias Musculares/classificação , Núcleo Familiar , Linhagem , Regiões Promotoras Genéticas , Sarcômeros/genética , Sarcômeros/metabolismo , Alinhamento de SequênciaRESUMO
The silverleaf whitefly (Bemisia tabaci) is actually a complex of morphologically indistinct species that vary in their capacity to transmit plant viruses and to induce physiological disorders in plants of economic importance. The worldwide impact of this whitefly has increased greatly, as it is a vector of various types of phytovirus, especially geminiviruses, in plants of economic importance. The adaptability of B. tabaci to many regions of the world has fostered the appearance of various biotypes that attack a broad spectrum of host plants. We developed microsatellite markers to study genetic variability and population structure of this whitefly in Brazil. Thirteen polymorphic microsatellite markers were isolated and characterized in 20 individuals from a natural population that were collected in soybean in Campinas (SP). The number of alleles per locus ranged from one to two, and the expected heterozygosity ranged from 0.000 to 0.505. These microsatellite markers will be useful for studies and management of B. tabaci. The low polymorphism found in these molecular markers is probably associated with homology of genes expressed in these markers.
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Hemípteros/genética , Repetições de Microssatélites/genética , Polimorfismo Genético , Animais , Loci Gênicos/genética , Dados de Sequência MolecularRESUMO
Pulses extruded foods can be envisaged asall solid foams with voids and walls, the latter being considered as a dense starch/protein composite. Pea flour (PF) and blends of pea starch and pea protein isolate (PPI) with different protein contents (0.5-88% dry basis) were extruded to obtain models of dense starch-protein composites. Their morphology was revealed by CLSM microscopy, and their mechanical properties were investigated using a three-point bending test complemented by Finite Element Method (FEM) modelling. Composite morphology revealed protein aggregates dispersed in the starch matrix. It was described by a starch-protein interface index Ii computed from the measured total area and perimeter of protein aggregates. The mechanical test showed that the extruded PF and PPI ruptured in the elastic domain, while the extruded starch-PPI (SP) blends ruptured in the plasticity domain. The mechanical properties of pea composites were weakened by increasing the particle volume fractions, including proteins and fibres, probably due to the poor adhesion between starch and the other constituents. The mechanical behaviour of pea composites did not accurately follow simple mixing laws because of their morphological heterogeneity. Modelling results show that the elastoplastic constitutive model using the Voce plasticity model satisfactorily described the hardening behaviour of SP blend composites. Reasonable agreement (2-10%) was found between the experimental and modelling approaches for most materials. The computed Young's modulus (1.3-2.5 GPa) and saturation flow stress (20-45 MPa) increased with increasing Ii (0.7-3.1), reflecting the increase of interfacial stiffening with the increase of contact area between starch and proteins. FEM modelling allowed to identify the mechanical effect of structural heterogeneities.
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Proteínas de Ervilha , Lanches , Pisum sativum , Agregados Proteicos , Análise de Elementos Finitos , Parede Celular , AmidoRESUMO
Artificial boluses were prepared from sponge cake by grinding the food to a given particle size and hydrating with artificial saliva. The shear viscosity of the artificial food bolus was then measured by capillary rheometry, and its variations with shear rate were studied as a function of four main factors: bolus water content, particle size, temperature and saliva viscosity. The flow curves can be fitted according to the Herschel-Bulkley model, which allows for the derivation of two main properties: yield stress and consistency. Saliva plasticizing coefficients are defined by the variations of these properties as a function of the water content. Their value, close to 12, is in good agreement with values obtained for molten starch (10 < α < 20). Particle size has little influence, whereas the effect of temperature and saliva viscosity is not monotonous. They underline the complexity of the structure of the bolus and the interplay between the saliva, acting as a lubricant and a swelling agent. Finally, the extensional viscosity of the artificial bolus is also determined by capillary rheometry, and it is shown to be of importance when comparing the viscous properties of the artificial bolus with those of real ones from literature.