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1.
One Health ; 18: 100724, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38623500

RESUMO

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.

2.
Food Res Int ; 162(Pt B): 112047, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36461312

RESUMO

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.


Assuntos
Proteínas de Ervilha , Lanches , Pisum sativum , Agregados Proteicos , Análise de Elementos Finitos , Parede Celular , Amido
3.
Food Funct ; 13(6): 3198-3205, 2022 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-35244631

RESUMO

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.


Assuntos
Alimentos , Mastigação , Saliva , Idoso , Humanos , Tamanho da Partícula , Reologia , Temperatura , Viscosidade , Água/análise
4.
Food Funct ; 11(5): 4535-4547, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32396930

RESUMO

This study investigated the oral processing and bolus formation mechanisms of two soft cereal products fortified with pulse proteins, sponge-cake (FSC) and brioche (FB), in the elderly population, and their relationship with the perception of oral comfort. Twenty subjects aged 65 and over participated in the study. They were classified in two groups according to dental status (poor vs. satisfactory) and presented varying stimulated salivary flow rate (SSF). Bolus properties (hydration ratio, apparent viscosity and particle size) were characterized after three chewing stages. Results showed that subjects with a poor dental status (DS) had a longer chewing duration for FB, while individuals with a higher SSF had a shorter duration for FSC. Compared to FSC, more saliva was added to the FB boli, and the viscosity and particle size of FB bolus were also higher. Based on the bolus particle size evolution during chewing, FB was considered to be more difficult to fragment than FSC, this latter showing a dramatic particle size reduction from the beginning of chewing. From the viscosity data, a model was used to represent the variations of the bolus structure index during chewing and a coefficient of interaction of saliva with food was defined. For both products, the perception of comfort depended more on the DS than on SSF. Bolus apparent viscosity was related to the perception of oral comfort in FSC, while the chewing duration and the bolus particle size at the beginning of chewing contributed to explain oral comfort in FB. Finally, the comparison of these results with those obtained previoulsy with standard (i.e. non enriched) sponge cake and brioche suggested that the proposed protein fortification did not challenge the oral comfort perception by the elderly.


Assuntos
Grão Comestível , Alimentos Especializados , Mastigação , Saúde Bucal , Idoso , Idoso de 80 Anos ou mais , Feminino , Idoso Fragilizado , Humanos , Masculino , Viscosidade
5.
Carbohydr Polym ; 223: 115086, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31426950

RESUMO

Starch-legume protein composites were obtained by extrusion of pea flour and pea starch-protein blend at various specific mechanical energies (100-2000 kJ/kg) and a temperature low enough to avoid expansion. The morphology of these composites displayed protein aggregates dispersed in a starch matrix, revealed by microscopy. Image analysis was used to determine the median width of protein aggregates (D50), their total perimeter and surface, from which a protein/starch interface index (Ii) was derived. The mechanical properties of composites were determined by a three-point bending test. The pea flour composites had a higher interface index Ii (1.8-3.1) with lower median particle width D50 (8-18 µm) and a more brittle behaviour than the blend composites that had a lower Ii (1-1.1) and higher D50 (22-31 µm). For both materials, rupture stress and strain were negatively correlated with Ii. This result suggested that there was a poor interfacial adhesion between the pea starch and proteins.


Assuntos
Proteínas de Ervilha/química , Pisum sativum/química , Amido/química , Cor , Teste de Materiais , Tamanho da Partícula , Propriedades de Superfície , Temperatura
6.
Food Res Int ; 118: 13-21, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30898347

RESUMO

The aim of this study was to investigate food oral processing and bolus formation in the elderly population, and their relationship with the perception of oral comfort, for two soft cereal products of different composition: sponge-cake and brioche. Twenty subjects aged 65 and over participated in the study. They were classified in two groups according to dental status (poor vs. satisfactory) and presented various stimulated salivary flow rate (SSF) in each group. Food bolus properties (hydration ratio and apparent viscosity) were characterized after three chewing stages for both groups. Results showed that chewing duration did not depend on food product but rather on physiology: subjects with a poor dental status had a shorter chewing duration. For each chewing stage, sponge-cake boli showed a higher hydration ratio than brioche boli, which showed higher apparent viscosity. For sponge-cake, perception of oral comfort was primarily driven by SSF rate, irrespective of the dental status. In the case of brioche, oral comfort was also partially explained by SSF in the case of subjects with poor dental status. This result suggests that perception of oral comfort in brioche could be driven by product related attributes rather than oral health. For both foods, a phenomenological model of bolus viscosity as a function of stimulated salivary flow and chewing duration was proposed.


Assuntos
Grão Comestível , Mastigação/fisiologia , Saúde Bucal , Percepção/fisiologia , Salivação/fisiologia , Idoso , Feminino , Humanos , Masculino , Análise Multivariada , Saliva , Inquéritos e Questionários , Viscosidade
7.
Food Res Int ; 108: 203-215, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29735050

RESUMO

Dehulled yellow pea flour (48.2% starch, 23.4% proteins, d.b.), was processed by a twin-screw extruder at various moisture contents MC (18-35% w.b.), product temperature T (115-165 °C), and specific mechanical energy SME (50-1200 kJ/kg). Structural changes of extruded pea flour were determined at different scales by measurements of density (expansion), crystallinity (X-ray diffraction), gelatinisation enthalpy (DSC), starch solubility in water and protein solubility in SDS and DTE (SE-HPLC). Foam density dropped from 820 to 85 kg/m3 with increase in SME and T (R2 ≥ 0.78). DSC and XRD results showed that starch was amorphous whatever extrusion conditions. Its solubility in water augmented up to 50%. Increasing temperature from 115 to 165 °C decreased proteins soluble in SDS from 95 to 35% (R2 = 0.83) of total proteins, whereas the proteins soluble in DTE increased from 5 to 45% (R2 = 0.75) of total proteins. These trends could be described by sigmoid models, which allowed determining onset temperatures for changes of protein solubility in the interval [125, 146 °C], whatever moisture content. The SME impact on protein solubility followed similar trends. These results suggest the creation of protein network by SS bonds, implicating larger SDS-insoluble protein aggregates, as a result of increasing T and SME, accompanied by creation of covalent bonds other than SS ones. CSLM images suggested that extruded pea flour had a composite morphology that changed from dispersed small protein aggregates to a bi-continuous matrix of large protein aggregates and amorphous starch. This morphology would govern the expansion of pea flour by extrusion.


Assuntos
Análise de Alimentos/métodos , Manipulação de Alimentos/métodos , Pisum sativum/química , Proteínas de Vegetais Comestíveis/química , Sementes/química , Amido/química , Configuração de Carboidratos , Cor , Cristalização , Agregados Proteicos , Conformação Proteica , Solubilidade , Relação Estrutura-Atividade , Temperatura , Água/química
8.
Anat Histol Embryol ; 47(3): 250-253, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29542176

RESUMO

The aim of this work is to assess the normal ultrasonographic features and dimensions of eyes in European hares. Corneal thickness, anterior chamber depth, lens thickness, vitreous chamber depth and eye axial length were measured by ultrasound in 40 healthy hares (Lepus europaeus), 20 males and 20 females, mean age of 5.5 months (range 2-15 months). The effects of sex, side, age and body weight on each feature were recorded. Results show that ocular dimensions were not affected by considered variables except for the lenses thickness and axial length that were correlated with age and body weight. Our study concludes that although ocular structures had similar feature compared to other species, the description of the characteristics of the eye of the European hare is important to widen the knowledge of a species not completely known from the normal anatomical point of view. The lens dimensions could have a predictive value in determining the age of young hares.


Assuntos
Olho/diagnóstico por imagem , Lebres/anatomia & histologia , Ultrassonografia/veterinária , Animais , Biometria/métodos , Feminino , Masculino
9.
Food Res Int ; 97: 123-132, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28578032

RESUMO

Wheat flour doughs were processed with soluble dietary fibres (DF) added up to 40% (w/w flour). DF were made of a ternary mixture of maltodextrins (MT, 3/5), pectins (PE, 1/5) and inulin (IN, 1/5). The addition of DF decreased the specific mechanical energy developed by the mixer, mainly because of water addition. It increased the ratio of storage moduli and the elongational viscosity of the dough, but decreased the strain hardening index. Energy input and rheological changes at mixing largely explained the decreases of porosity characteristic time and stability time during fermentation. It was possible to add up to 30% DF with a moderate increase of bread density, and 20%, with little change of crumb cellular structure. Hence, the changes of bread crumb texture were not mainly due to bread density, but rather likely to the changes of properties of the intrinsic material. Results obtained by addition of single fibre source, especially inulin, deviated from the main trends observed for texture and rheological properties. These results provide a good basis to design breads with increased dietary fibre content.


Assuntos
Pão/análise , Fibras na Dieta/análise , Farinha/análise , Triticum/química , Fermentação , Reologia , Viscosidade
10.
Open Vet J ; 6(3): 255-258, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28116250

RESUMO

The objective of this paper was to describe the clinical features, the management and the outcome of nine small breed dogs affected with lateral patella luxation referred during the period between January 2010 and December 2014. Patellar luxations were classified according to: breed, age, sex, weight, and grade of patellar luxation, as well as if unilateral or bilateral, and concurrent cranial cruciate ligament lesion. In affected dogs, surgical correction consisted in the combination of tibial tuberosity transposition and soft tissue procedure. Adjunctive condroplasty or trochleoplasty was performed as needing. The outcome was found positive after surgical management with low complication rate and complications have been easily managed with high success rate.

11.
Folia Morphol (Warsz) ; 75(2): 211-215, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26431049

RESUMO

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.


Assuntos
Teratoma/veterinária , Neoplasias Testiculares/veterinária , Envelhecimento , Animais , Criptorquidismo , Virilha , Doenças dos Cavalos , Cavalos , Masculino , Testículo , Ultrassonografia
12.
Soft Matter ; 11(17): 3373-84, 2015 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-25816111

RESUMO

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.


Assuntos
Fermentação , Farinha , Gases/química , Transição de Fase , Elasticidade , Porosidade , Viscosidade , Microtomografia por Raio-X
13.
Opt Lett ; 39(23): 6636-9, 2014 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-25490640

RESUMO

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.

14.
Phys Rev Lett ; 111(22): 220403, 2013 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-24329428

RESUMO

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.

15.
J Phys Condens Matter ; 25(23): 235601, 2013 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-23670177

RESUMO

In the framework of the Bose-Hubbard model, we show that two-particle surface bound states embedded in the continuum (BIC) can be sustained at the edge of a semi-infinite one-dimensional tight-binding lattice for any infinitesimally-small impurity potential V at the lattice boundary. Such thresholdless surface states, which can be referred to as Tamm-Hubbard BIC states, exist provided that the impurity potential V is attractive (repulsive) and the particle-particle Hubbard interaction U is repulsive (attractive), i.e. for UV < 0.

16.
Opt Express ; 18(19): 20289-97, 2010 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-20940920

RESUMO

We report on the first demonstration of an optical waveguide amplifier in phospho-tellurite glass providing net gain at 1.5 µm. The device was fabricated using a high repetition rate femtosecond laser and exhibited internal gain across 100-nm bandwidth covering the entire C + L telecom bands.


Assuntos
Amplificadores Eletrônicos , Vidro/química , Lasers , Fósforo/química , Refratometria/instrumentação , Telúrio/química , Desenho de Equipamento , Análise de Falha de Equipamento
17.
Opt Lett ; 35(5): 673-5, 2010 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-20195315

RESUMO

We study subwavelength light propagation in arrays of coupled metal-dielectric waveguides with a periodically curved axis and show analytically and numerically that subwavelength diffraction management, including self-imaging effects, can be achieved by a suitable engineering of the bending geometry.

18.
Science ; 326(5954): 865-7, 2009 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-19892987

RESUMO

We report a high-quality draft sequence of the genome of the horse (Equus caballus). The genome is relatively repetitive but has little segmental duplication. Chromosomes appear to have undergone few historical rearrangements: 53% of equine chromosomes show conserved synteny to a single human chromosome. Equine chromosome 11 is shown to have an evolutionary new centromere devoid of centromeric satellite DNA, suggesting that centromeric function may arise before satellite repeat accumulation. Linkage disequilibrium, showing the influences of early domestication of large herds of female horses, is intermediate in length between dog and human, and there is long-range haplotype sharing among breeds.


Assuntos
Cromossomos de Mamíferos/genética , Genoma , Cavalos/genética , Análise de Sequência de DNA , Animais , Animais Domésticos/genética , Centrômero/genética , Mapeamento Cromossômico , Biologia Computacional , Variações do Número de Cópias de DNA , Cães , Evolução Molecular , Feminino , Genes , Haplótipos , Humanos , Dados de Sequência Molecular , Filogenia , Sequências Repetitivas de Ácido Nucleico , Sintenia
19.
Phys Rev Lett ; 102(18): 180402, 2009 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-19518846

RESUMO

An optical analogue of a quantum particle bouncing on a hard surface under the influence of gravity (a quantum bouncer) is experimentally demonstrated using a circularly curved optical waveguide. Spatially resolved tunneling optical microscopy measurements of multiple beam reflections at the waveguide edge clearly show the appearance of wave packet collapses and revivals (either integer and fractional), corresponding to the full quantum regime of the quantum bouncer.

20.
Mol Biol Evol ; 26(8): 1889-900, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19429672

RESUMO

The evolutionary history of alpha-satellite DNA, the major component of primate centromeres, is hardly defined because of the difficulty in its sequence assembly and its rapid evolution when compared with most genomic sequences. By using several approaches, we have cloned, sequenced, and characterized alpha-satellite sequences from two species representing critical nodes in the primate phylogeny: the white-cheeked gibbon, a lesser ape, and marmoset, a New World monkey. Sequence analyses demonstrate that white-cheeked gibbon and marmoset alpha-satellite sequences are formed by units of approximately 171 and approximately 342 bp, respectively, and they both lack the high-order structure found in humans and great apes. Fluorescent in situ hybridization characterization shows a broad dispersal of alpha-satellite in the white-cheeked gibbon genome including centromeric, telomeric, and chromosomal interstitial localizations. On the other hand, centromeres in marmoset appear organized in highly divergent dimers roughly of 342 bp that show a similarity between monomers much lower than previously reported dimers, thus representing an ancient dimeric structure. All these data shed light on the evolution of the centromeric sequences in Primates. Our results suggest radical differences in the structure, organization, and evolution of alpha-satellite DNA among different primate species, supporting the notion that 1) all the centromeric sequence in Primates evolved by genomic amplification, unequal crossover, and sequence homogenization using a 171 bp monomer as the basic seeding unit and 2) centromeric function is linked to relatively short repeated elements, more than higher-order structure. Moreover, our data indicate that complex higher-order repeat structures are a peculiarity of the hominid lineage, showing the more complex organization in humans.


Assuntos
Evolução Biológica , Callithrix/genética , Centrômero/genética , Hylobates/genética , Animais , Linhagem Celular , Humanos , Primatas/genética
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