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1.
Animal ; 18(3): 101100, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38452419

RESUMO

The need to integrate more clearly societal expectations on livestock farming has led the authors of this article to consider that livestock farming systems must be redesigned to position health and welfare at the heart of their objectives. This article proposes a vision of the advances in knowledge required at different scales to contribute to this transformation. After defining health and welfare of animals, the article emphasises the need to consider health in a broader perspective, to deepen the question of positive emotional experiences regarding welfare, and raises the question of how to assess these two elements on farms. The positive interactions between health and welfare are presented. Some possible tensions between them are also discussed, in particular when improving welfare by providing a more stimulating and richer environment such as access to outdoor increases the risk of infectious diseases. Jointly improving health and welfare of animals poses a number of questions at various scales, from the animal level to the production chain. At the animal level, the authors highlight the need to explore: the long-term links between better welfare and physiological balance, the role of microbiota, the psycho-neuro-endocrine mechanisms linking positive mental state and health, and the trade-off between the physiological functions of production, reproduction and immunity. At the farm level, in addition to studying the relationships at the group level between welfare, health and production, the paper supports the idea of co-constructing innovative systems with livestock farmers, as well as analysing the cost, acceptability and impact of improved systems on their working conditions and well-being. At the production chain or territory levels, various questions are raised. These include studying the best strategies to improve animal health and welfare while preserving economic viability, the labelling of products and the consumers' willingness to pay, the consequences of heterogeneity in animal traits on the processing of animal products, and the spatial distribution of livestock farming and the organisation of the production and value chain. At the level of the citizen and consumer, one of the challenges is to better inter-relate sanitary and health perspectives on the one hand, and welfare concerns on the other hand. There is also a need to improve citizens' knowledge on livestock farming, and to develop more intense and constructive exchanges between livestock farmers, the livestock industry and citizens. These difficult issues plead for interdisciplinary and transdisciplinary research involving various scientific disciplines and the different stakeholders, including public policy makers through participatory research.


Assuntos
Criação de Animais Domésticos , Gado , Animais , Humanos , Fazendas , Bem-Estar do Animal , Fazendeiros
2.
ESMO Open ; 6(3): 100106, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33865192

RESUMO

Squamous cell carcinomas (SCCs) are among the most frequent solid tumors in humans. SCCs, related or not to the human papillomavirus, share common molecular features. Immunotherapies, and specifically immune checkpoint inhibitors, have been shown to improve overall survival in multiple cancer types, including SCCs. However, only a minority of patients experience a durable response with immunotherapy. Epigenetic modulation plays a major role in escaping tumor immunosurveillance and confers resistance to immune checkpoint inhibitors. Preclinical evidence suggests that modulating the epigenome might improve the efficacy of immunotherapy. We herein review the preclinical and the clinical rationale for combining immunotherapy with an epidrug, and detail the design of PEVOsq, a basket clinical trial combining pembrolizumab with vorinostat, a histone deacetylase inhibitor, in patients with SCCs of different locations. Sequential blood and tumor sampling will be collected in order to identify predictive and pharmacodynamics biomarkers of efficacy of the combination. We also present how clinical and biological data will be managed with the aim to enable the development of a prospective integrative platform to allow secure and controlled access to the project data as well as further exploitations.


Assuntos
Alphapapillomavirus , Carcinoma de Células Escamosas , Carcinoma de Células Escamosas/tratamento farmacológico , Humanos , Imunoterapia , Papillomaviridae , Estudos Prospectivos
4.
Mar Environ Res ; 149: 111-125, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31280120

RESUMO

The Campeche Sound is the major offshore oil producing area in the Southern Gulf of Mexico (SGoM). To evaluate the impact of oil related activities in the ocean floor sediments, we analyzed the geochemical (major and trace element, organic carbon and hydrocarbon concentrations) and biological (benthic foraminifera) composition of 62 superficial sediment samples, from 13 to 1336 m water depth. Cluster and Factor analysis of all the variables indicate that their distribution patterns are mainly controlled by differences between the terrigenous and carbonate platforms in the SGoM. Benthic foraminiferal assemblages were abundant and diverse, and their distribution patterns are mainly determined by water depth and sedimentary environment. However, most of the abundant species are opportunistic and/or low-oxygen tolerant, and many of their tests show oil stains and infillings, characteristic of oil polluted locations, suggesting the environment has been modified by natural seepage or oil-related activities. To determine if these conditions are natural or anthropogenic in origin, pre - industrial settings should be studied. Organic carbon (Corg) content (0.6-2.9%) and total hydrocarbon concentrations (PAHs 1.0-29.5 µg kg-1) were usually higher around the oil platforms area, the natural hydrocarbon seeps ("chapopoteras") area and offshore rivers, but there is no accumulation of oil related trace elements in these areas. However, the comparison with international sediment quality benchmarks indicates that Cd, Cr and Ni concentrations are above the threshold effect level, and also As, Ba and Cu are above the probable effect level benchmarks, which indicate that these element concentrations might be of potential ecological concern. Comprehensive studies involving different proxies, and assessing pre-industrial conditions, must be undertaken before assessing environmental health of marine benthic ecosystems.


Assuntos
Monitoramento Ambiental , Foraminíferos/química , Sedimentos Geológicos/química , Hidrocarbonetos Policíclicos Aromáticos/análise , Oligoelementos/análise , Poluentes Químicos da Água/análise , Biodiversidade , Foraminíferos/classificação , Golfo do México , Poluição por Petróleo
5.
J Antimicrob Chemother ; 74(10): 2979-2983, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31335959

RESUMO

BACKGROUND: The pharmacokinetics (PK) of antibiotics change during sepsis and continuous renal replacement therapies in critically ill patients. Limited evidence exists on the use of the oXiris® high-adsorbent membrane. OBJECTIVES: To develop a PK/pharmacodynamic (PD) model for meropenem in critically ill sepsis patients undergoing continuous venovenous haemodiafiltration (CVVHDF) with the oXiris® membrane, and to design an optimal dosing regimen assessed according to the PTA. METHODS: A prospective, open-label, observational PK trial was performed (EUDRACT 2011-005902-30). We conducted PK studies (plasma and ultrafiltrate) for at least 24 h after concomitant administration of CVVHDF and meropenem 1 g q8h. We constructed a PK model using the non-linear mixed-effects approach (NONMEM 7.3). We evaluated the suitability of different dosage regimens using Monte Carlo simulations and calculated the PTA as the percentage of subjects achieving a given percentage of time above the MIC (fT>MIC). RESULTS: The PK of meropenem was best captured by a two-open-compartment model with zero-order input kinetics and first-order elimination. Extracorporeal CL was 7.78 L/h [relative standard error (RSE) 16.45 L/h] and central compartment V (Vc) was 24.9 L (RSE 13.73 L). Simulations showed that, for susceptible Pseudomonas aeruginosa isolates (EUCAST MIC ≤2 mg/L) and attainment of 100%fT>MIC, 500 mg q8h given as extended (EI) or continuous infusion (CI) would be sufficient. For a target of 100%fT>4×MIC, CI of 3000 mg q24h or 2000 mg q8h administered as EI or CI would be required. CONCLUSIONS: We have constructed a PK model of meropenem in sepsis patients undergoing CVVHDF using the oXiris® membrane. This tool will support physicians when calculating the optimal initial dose.


Assuntos
Antibacterianos/administração & dosagem , Antibacterianos/farmacocinética , Meropeném/administração & dosagem , Meropeném/farmacocinética , Adulto , Idoso , Idoso de 80 Anos ou mais , Terapia de Substituição Renal Contínua/métodos , Estado Terminal , Feminino , Humanos , Masculino , Testes de Sensibilidade Microbiana/métodos , Pessoa de Meia-Idade , Método de Monte Carlo , Estudos Prospectivos , Pseudomonas aeruginosa/efeitos dos fármacos , Sepse/tratamento farmacológico
6.
Poult Sci ; 98(11): 6149-6160, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31162617

RESUMO

Spontaneous liver steatosis can be experimentally induced in domestic Greylag geese by combining a short photoperiod with a sequence of feed restriction followed by ad libitum corn feeding. This could offer an alternative to the conventional "foie gras" production system based on overfeeding. The present work aimed at comparing the compositional characteristics, sensory profile, and acceptability by a consumer panel of fatty livers obtained by overfeeding and spontaneous fattening. In all, 210 male geese were used: 125 geese were raised over a 31-wk period to produce fatty liver without overfeeding ("alternative livers") and 85 were raised using conventional methods with overfeeding ("conventional livers"). Mean liver weight was over 1 kg (1,102 g) in the conventional group and 445 g in the alternative group. The characteristics of the livers were studied in 2 subpopulations: 44 conventional livers representative of the experimental population (mean liver weight 1,064 g) and 42 alternative livers weighing more than 400 g (mean 702 g). Compared with the alternative livers, livers from the conventional group showed significantly (P < 0.05) higher dry matter and lipid contents, lighter color (L*), and lower yellowness (b*). The neutral lipids of alternative livers contained significantly less triglycerides and free fatty acids and significantly more cholesterol and cholesterol esters than those from conventional livers. Detailed analysis of the fatty acid composition of triglycerides showed that the proportion of mono- and polyunsaturated fatty acids was significantly higher in the alternative livers. However, covariance analysis suggested that these differences in lipid composition were mainly due to differences in lipid content between both types of livers. The evaluation of cooked livers by a trained expert panel revealed significant differences in the sensory profile between the conventional and alternative livers. The acceptability by a consumer panel was significantly lower in alternative compared to conventional livers. This difference was not related to weight and/or lipid content since livers of similar weight range (800 to 1,000 g) were compared and showed clear-cut differences for hedonic scores.


Assuntos
Criação de Animais Domésticos/métodos , Qualidade dos Alimentos , Gansos/fisiologia , Metabolismo dos Lipídeos , Fígado/química , Ração Animal/análise , Animais , Dieta/veterinária , Fígado Gorduroso , Masculino
7.
AJNR Am J Neuroradiol ; 40(4): 737-744, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30923086

RESUMO

BACKGROUND AND PURPOSE: Our aim was to use 2D convolutional neural networks for automatic segmentation of the spinal cord and traumatic contusion injury from axial T2-weighted MR imaging in a cohort of patients with acute spinal cord injury. MATERIALS AND METHODS: Forty-seven patients who underwent 3T MR imaging within 24 hours of spinal cord injury were included. We developed an image-analysis pipeline integrating 2D convolutional neural networks for whole spinal cord and intramedullary spinal cord lesion segmentation. Linear mixed modeling was used to compare test segmentation results between our spinal cord injury convolutional neural network (Brain and Spinal Cord Injury Center segmentation) and current state-of-the-art methods. Volumes of segmented lesions were then used in a linear regression analysis to determine associations with motor scores. RESULTS: Compared with manual labeling, the average test set Dice coefficient for the Brain and Spinal Cord Injury Center segmentation model was 0.93 for spinal cord segmentation versus 0.80 for PropSeg and 0.90 for DeepSeg (both components of the Spinal Cord Toolbox). Linear mixed modeling showed a significant difference between Brain and Spinal Cord Injury Center segmentation compared with PropSeg (P < .001) and DeepSeg (P < .05). Brain and Spinal Cord Injury Center segmentation showed significantly better adaptability to damaged areas compared with PropSeg (P < .001) and DeepSeg (P < .02). The contusion injury volumes based on automated segmentation were significantly associated with motor scores at admission (P = .002) and discharge (P = .009). CONCLUSIONS: Brain and Spinal Cord Injury Center segmentation of the spinal cord compares favorably with available segmentation tools in a population with acute spinal cord injury. Volumes of injury derived from automated lesion segmentation with Brain and Spinal Cord Injury Center segmentation correlate with measures of motor impairment in the acute phase. Targeted convolutional neural network training in acute spinal cord injury enhances algorithm performance for this patient population and provides clinically relevant metrics of cord injury.


Assuntos
Aprendizado Profundo , Interpretação de Imagem Assistida por Computador/métodos , Transtornos Motores/etiologia , Traumatismos da Medula Espinal/complicações , Traumatismos da Medula Espinal/diagnóstico por imagem , Contusões/diagnóstico por imagem , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Masculino
8.
Pathol Res Pract ; 212(5): 372-80, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26992835

RESUMO

BACKGROUND/OBJECTIVE: Risk adapted therapy is standard practice in Acute Myeloid Leukemia (AML). A common diagnostic approach involves focusing on a three gene panel (CEPBA, FLT3, and NPM1). However, a complete representation of prognostic and predictive factors in AML necessitates an expanded series of genes, due to the dynamic interactions present between concurrent mutations. Hence, the current study aims to describe the benefits of an expanded risk profile in an unselected cohort of AML cases. METHODS: The genomes of 11 randomly selected patients with AML were sequenced using next generation sequencing. A narrow three gene panel and broader 50 gene panel were contrasted. RESULTS: The expanded gene panel detected one additional pathogenic mutation in five patients and two pathogenic mutations in two patients, resulting in a change in their risk profile. Only 5/11 (45%) of AML patients demonstrated a pathogenic mutation on the 3 gene profile, however all patients had at least one detectable pathogenic mutation on the broader gene panel. The detection of a concurrent mutation by the expanded gene panel reversed the favorable risk profile for three patients. CONCLUSIONS: Detection of concurrent mutations enables rejection or validation of prognoses associated with NPM1 or CEBPA mutations. DNMT3a and TP53 mutations in AML have a pertinent prognostic and therapeutic value for patients and their addition enhances the current three gene panel. In our small study, the three gene panel changed the prognosis for three patients (3/11, 27%) with the detection of commonly occurring AML mutations.


Assuntos
Leucemia Mieloide Aguda/genética , Mutação , Feminino , Regulação da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Pessoa de Meia-Idade , Nucleofosmina , Prognóstico
9.
Animal ; 10(8): 1288-95, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26915402

RESUMO

We have previously demonstrated that a sharp rise in feed intake (hyperphagia) and spontaneous liver steatosis could be experimentally induced in domestic Greylag geese by combining a short photoperiod and a sequence of feed restriction followed by ad libitum corn feeding during the fall and the winter. In this previous work, however, individual feed intake could not be recorded. The present study aimed at evaluating the relationship between level and pattern of hyperphagia and liver weight with an individual control of feed intake in individually housed (IH) geese, while comparing the performances with group housed (GH) geese. A total of 300 male geese of 19 weeks of age, were provided with corn ad libitum after an initial feed restriction period. From 21 to 23 weeks of age, the daylight duration was progressively reduced from 10 to 7 h and kept as such until the end of the experiment (week 36). In all, 30 GH and 30 IH geese were slaughtered at 19, 27, 30, 32 and 36 weeks of age. Feed intake was measured per group in GH geese and individually in IH geese. During the 1st week of corn feeding, the average feed intake rose up to 600 g/goose per day in GH geese but not in IH geese where the feed intake rose gradually from 300 to 400 g/day. The liver weight increased from 93 g (week 19) to 497 g (week 32; P<0.05) in GH birds. In IH birds, liver weights were, on average, much lower (ranging from 220 to 268 g) than in GH birds (P<0.05). In GH and IH bird, the variability in the individual response to corn feeding was very high (liver weight cv ranging from 63% to 83% depending on slaughter age). A close correlation between corn consumption and liver weight was evidenced in IH birds at each slaughter age (R 2 ranging from 0.62 to 0.79), except at 36 weeks of age where this correlation was weak (R 2=0.14). The variability in the extent of liver steatosis is very high and our results in IH birds clearly point out the major role of hyperphagia, mainly at the beginning of the ad libitum corn feeding period, on the development of spontaneous liver steatosis.


Assuntos
Fígado Gorduroso/veterinária , Gansos , Hiperfagia/etiologia , Doenças das Aves Domésticas/etiologia , Animais , Fígado Gorduroso/etiologia , Comportamento Alimentar , Abrigo para Animais , Masculino
10.
Int J Cosmet Sci ; 37(1): 31-40, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25256527

RESUMO

OBJECTIVE: Preservation of cosmetics is a prerequisite for industrialization, and among the proposed solutions, self-preserved cosmetics are of great interest. One key influencing parameter in self-preservation is water activity; its reduction can help to fight against microbial growth in cosmetic products. This work presents a study on the influence of humectants on water activity and its consequence on the preservation of cosmetic formulations. METHODS: First, water-humectants mixtures were considered. The influence of glycol and glycerin content, glycol chemical structure, glycerin purity and formulation process on the water activity of the binary mixture was studied. Molecular modelling was performed for a better understanding of the impact of glycol chemistry. Then, the results were applied to five different cosmetic formulations to get optimized products. Challenge test on five strains was carried out in that sense. RESULTS: We showed that the higher the humectants concentration, the lower the water activity. Glycol chemical structure also influenced water activity: propan-1,2-diol was more efficient than propan-1,3-diol, certainly because of a better stabilization in water of propan-1,2-diol as shown by DFT calculation. A drop by drop introduction of glycol in water favoured aw reduction. The best water activity loss was 6.6% and was reached on the cream formulation whose preservation was improved as evidenced by challenge test. CONCLUSION: Fabrication process as well as humectants concentration were shown to influence water activity. The hydroxyl group positions as well as the presence of an alkyl group on the glycol carbon chain impacted water binding as suggested by DFT calculation. Reducing aw improved the preservation of a cosmetic cream, inhibiting or slowing down the growth of bacteria and fungi.


Assuntos
Cosméticos , Água
11.
Nat Prod Res ; 27(18): 1700-4, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23425125

RESUMO

Three essential oils from three samples: stems, leaves and inflorescences of Thymus maroccanus Ball, obtained by hydrodistillation, were analysed by gas chromatography and gas chromatography coupled to mass spectrometry. The oils of stems, leaves and inflorescences afforded 68, 49 and 51 constituents, respectively. Quantitative and qualitative differences have been found between the analysed parts. The most abundant components in the stems oil included carvacrol (60.8%), α-terpineol (4.7%) and p-cymene (2.4%), while carvacrol (33%), p-cymene (25.3%) and α-pinene (11.6%) were the main components in the leaves. In the inflorescences, carvacrol (84.9%) is the major component. Antibacterial activity of the T. maroccanus Ball leaves oil was tested against eight Gram-positive and Gram-negative bacteria by the disc diffusion method. The values of inhibition zones for bacterial strains, which were sensitive to the essential oil of T. maroccanus leaves, were in the range of 11-43 mm.


Assuntos
Antibacterianos/química , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Thymus (Planta)/química , Antibacterianos/farmacologia , Monoterpenos Bicíclicos , Monoterpenos Cicloexânicos , Cicloexenos/química , Cicloexenos/farmacologia , Cimenos , Cromatografia Gasosa-Espectrometria de Massas , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Monoterpenos/química , Monoterpenos/farmacologia , Marrocos
12.
J Anim Sci ; 91(1): 455-64, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23097395

RESUMO

The present experiment aimed at demonstrating that the Greylag geese (Anser anser), commonly used for the production of foie gras, are able to develop spontaneous hyperphagia and subsequent liver steatosis under specific handling conditions and without overfeeding. One hundred and eighty male geese were used in this experiment. After a period of feed restriction, at the age of 19 wk, corn was provided ad libitum. From wk 21 to 23, the daylight duration was progressively reduced from 10 to 7 h and kept as such until the end of the experiment (wk 31). Thirty birds were slaughtered at wk 19, 23, 25, 27, 29, and 31. During the first 2 wk after corn delivery, the average consumption rose up to 600 g/bird/d and decreased slowly thereafter to reach 270 g at wk 31. The liver weight increased from 95 (wk 19) to 514 g (wk 31), and most of these changes were due to the increase in liver lipid content from 6 to 50% of liver weight. There was no mortality during the experimental period. Histological observations indicate that the accumulation of fat in the livers occurred through a large increase in the size of the hepatocytes without modification of the cell boundaries and without any sign of inflammation or degeneration. Our data clearly show that under specific management conditions of feeding and photoperiod, the geese are able to initiate spontaneous liver steatosis. These results demonstrate their natural ability to store fat in the liver without any visible sign of tissue alteration. However, the variability in the response remains very high (at wk 31, the CV in liver weight was 45%). Further research is needed to better understand the origin of this variability.


Assuntos
Criação de Animais Domésticos , Anseriformes , Fígado Gorduroso/veterinária , Comportamento Alimentar , Doenças das Aves Domésticas/etiologia , Ração Animal/análise , Animais , Dieta/veterinária , Fígado Gorduroso/etiologia , Privação de Alimentos , Metabolismo dos Lipídeos , Lipídeos/química , Fígado/anatomia & histologia , Fígado/química , Fígado/crescimento & desenvolvimento , Masculino , Tamanho do Órgão , Zea mays
13.
J Anim Sci ; 91(2): 588-604, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23148259

RESUMO

The mule duck, an interspecific hybrid obtained by crossing common duck (Anas platyrhynchos) females with Muscovy (Cairina moschata) drakes, is widely used for fatty liver production. The purpose of the present study was to detect and map single and pleiotropic QTL that segregate in the common duck species, and influence the expression of traits in their overfed mule duck offspring. To this end, we generated a common duck backcross (BC) population by crossing Kaiya and heavy Pekin experimental lines, which differ notably in regard to the BW and overfeeding ability of their mule progeny. The BC females were mated to Muscovy drakes and, on average, 4 male mule ducks hatched per BC female (1600 in total) and were measured for growth, metabolism during growth and the overfeeding period, overfeeding ability, and the quality of their breast meat and fatty liver. The phenotypic value of BC females was estimated for each trait by assigning to each female the mean value of the phenotypes of her offspring. Estimations allowed for variance, which depended on the number of male offspring per BC and the heritability of the trait considered. The genetic map used for QTL detection consisted of 91 microsatellite markers aggregated into 16 linkage groups (LG) covering a total of 778 cM. Twenty-two QTL were found to be significant at the 1% chromosome-wide threshold level using the single-trait detection option of the QTLMap software. Most of the QTL detected were related to the quality of breast meat and fatty liver: QTL for meat pH 20 min post mortem were mapped to LG4 (at the 1% genome-wide significance level), and QTL for meat lipid content and cooking losses were mapped to LG2a. The QTL related to fatty liver weight and liver protein and lipid content were for the most part detected on LG2c and LG9. Multitrait analysis highlighted the pleiotropic effects of QTL in these chromosome regions. Apart from the strong QTL for plasma triglyceride content at the end of the overfeeding period mapped to chromosome Z using single-trait analysis, all metabolic trait QTL were detected with the multitrait approach: the QTL mapped to LG14 and LG21 affected the plasma cholesterol and triglyceride contents, whereas the QTL mapped to LG2a seemed to impact glycemia and the basal plasma corticosterone content. A greater density genetic map will be needed to further fine map the QTL.


Assuntos
Criação de Animais Domésticos/métodos , Cruzamentos Genéticos , Fígado/fisiologia , Carne/normas , Ração Animal , Animais , Dieta/veterinária , Patos/genética , Feminino , Ligação Genética , Genótipo , Masculino , Repetições de Microssatélites , Locos de Características Quantitativas , Fatores Sexuais
14.
J Inorg Biochem ; 117: 359-66, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23062699

RESUMO

Ti6Al4V alloy is the most commonly employed implant material for orthopedic replacements due to its good mechanical properties close to those of bones, biocompatibility and its good corrosion resistance in biological media. Nevertheless, it does not exhibit good wear resistance, showing friction and wear even with soft tissues. This latter feature can lead to a premature failure of the implant with the subsequent component replacement. Therefore, a system with good tribological resistance is required for several medical applications. One possible alternative to solve tribological problems consists of protecting the alloy surface by means of biocompatible Ti-C-N coatings. In this work, five types of metallic Ti-C-N coatings deposited by physical vapor deposition (PVD) cathodic arc method on Ti6Al4V substrate have been studied. Different deposition conditions have been analyzed, and the superficial properties of films have been characterized. Additionally, tribological response of these films have been determined and compared with the substrate one under fretting conditions in simulated body fluid. The results indicate that Ti-C-N coatings improve the general response of the biomaterial.


Assuntos
Ligas/química , Materiais Revestidos Biocompatíveis/química , Titânio/química , Teste de Materiais , Próteses e Implantes , Análise Espectral Raman , Propriedades de Superfície , Difração de Raios X
15.
J Anim Sci ; 90(9): 3312-7, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22585814

RESUMO

The fatty liver of mule ducks (i.e., French "foie gras") is the most valuable product in duck production systems. Its quality is measured by the technological yield, which is the opposite of the fat loss during cooking. The purpose of this study was to determine whether biochemical measures of fatty liver could be used to accurately predict the technological yield (TY). Ninety-one male mule ducks were bred, overfed, and slaughtered under commercial conditions. Fatty liver weight (FLW) and biochemical variables, such as DM, lipid (LIP), and protein content (PROT), were collected. To evaluate evidence for nonlinear fat loss during cooking, we compared regression models describing linear and nonlinear relations between biochemical measures and TY. We detected significantly greater (P = 0.02) linear relation between DM and TY. Our results indicate that LIP and PROT follow a different pattern (linear) than DM and showed that LIP and PROT are nonexclusive contributing factors to TY. Other components, such as carbohydrates, other than those measured in this study, could contribute to DM. Stepwise regression for TY was performed. The traditional model with FLW was tested. The results showed that the weight of the liver is of limited value in the determination of fat loss during cooking (R(2) = 0.14). The most accurate TY prediction equation included DM (in linear and quadratic terms), FLW, and PROT (R(2) = 0.43). Biochemical measures in the fatty liver were more accurate predictors of TY than FLW. The model is useful in commercial conditions because DM, PROT, and FLW are noninvasive measures.


Assuntos
Fígado Gorduroso , Produtos Avícolas/análise , Animais , Culinária , Patos , Fígado/química , Masculino , Modelos Biológicos
16.
J Proteomics ; 75(14): 4290-5, 2012 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-22575383

RESUMO

In this review, an overview on proteomic studies conducted in livers of farm animals is conducted with a special focus on liver steatosis in waterfowl. Several studies had interest in understanding liver metabolism in dairy cows under various conditions (e.g. fasting) or the evolution of liver proteome during embryonic phases or growing periods in chicken. Those studies provide interesting results leading to a better understanding of the liver metabolism. Liver steatosis development in waterfowl represents a special case and a focus on proteomic studies conducted in these birds will be done. Indeed, recent studies aimed at resolving protein evolution during overfeeding in duck. Proteomic analysis combining two complementary approaches (2-dimensional electrophoresis gels and shot gun strategy) in order to better understand the mechanisms underlying the variability of cooking yield of fatty liver will be presented.


Assuntos
Patos/metabolismo , Fígado Gorduroso/veterinária , Perfilação da Expressão Gênica/tendências , Perfilação da Expressão Gênica/veterinária , Doenças das Aves Domésticas/metabolismo , Proteoma/análise , Proteômica/tendências , Animais , Fígado Gorduroso/metabolismo
17.
Phytochem Anal ; 23(5): 450-5, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22213588

RESUMO

INTRODUCTION: Iris resinoid obtained from Iris germanica or Iris pallida rhizomes is widely used in the perfume industry but its chemical composition has not yet been reported. Nevertheless, very active compounds have been identified in iris rhizomes including iridals and isoflavones. OBJECTIVE: In this first study concerning iris resinoid composition, flavonoids were qualitatively and quantitatively investigated in I. germanica and I. pallida resinoids. METHODOLOGY: Resinoids were first fractionated by reverse-phase flash chromatography in order to obtain fractions containing all isoflavones. These fractions were analysed by HPLC-DAD (diode array detector) and the fractions containing isoflavones were analysed by HPLC-QTOF (quadrupole time of flight)-MS. Then, the main isoflavones were isolated and identified by NMR and high-resolution mass spectroscopy (HRMS). Finally, total and individual isoflavones were quantified by HPLC-DAD at 265 nm using an external calibration method with irigenin as the external standard. RESULTS: Eight isoflavones were identified in both resinoids (irigenin, iristectorigenin A, nigricin, nigricanin, irisflorentin, iriskumaonin methyl ether, irilone, iriflogenin), one isoflavone only was identified in I. germanica resinoid (irisolidone), whereas one isoflavone (8-hydroxyirigenin), one isoflavanone (2,3-dihydroirigenin) and one benzophenone (2,6,4'-trihydroxy-4-methoxybenzophenone) only were identified in I. pallida resinoid. Isoflavones were quantified in I. germanica and I. pallida resinoids at 180 ± 1.6 mg/g and 120 ± 3.3 mg/g respectively. CONCLUSION: The study shows that I. germanica and I. pallida resinoids are rich in flavonoids and that these two Iris species can be distinguished by simply analysing the polyphenol fraction.


Assuntos
Flavonoides/isolamento & purificação , Gênero Iris/química , Isoflavonas/isolamento & purificação , Rizoma/química , Benzofenonas/química , Benzofenonas/isolamento & purificação , Fracionamento Químico/métodos , Cromatografia Líquida de Alta Pressão/métodos , Flavonoides/química , Isoflavonas/química , Espectroscopia de Ressonância Magnética , Espectrometria de Massas/métodos , Marrocos , Especificidade da Espécie
18.
Poult Sci ; 91(1): 112-20, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22184436

RESUMO

We investigated a protein profile evolution during steatosis in ducks using 2-dimensional electrophoresis gels to better understand the mechanisms underlying liver steatosis at the level of hepatic proteins in waterfowl. Two-dimensional electrophoresis gels were performed in the liver at different stages of steatosis in the duck. Mule ducks were slaughtered after 0, 14, or 23 meals of overfeeding, according to commercial conditions. Thirty-one proteic spots were differentially expressed between 3 or 2 durations of overfeeding: 3 spots were differentially expressed between the 3 times and 28 spots were differentially expressed between 2 times. The identified proteins (14) could be regrouped into 5 categories: enzymes, translation factors, proteins involved in cell structure, proteins with antioxidant properties, and proteins that can link calcium. This study opens new research areas in the understanding of steatosis in waterfowl, such as cell structure and oxidative stress.


Assuntos
Cálcio/metabolismo , Patos , Fígado Gorduroso/veterinária , Fígado/metabolismo , Doenças das Aves Domésticas/metabolismo , Proteoma/metabolismo , Animais , Antioxidantes/análise , Antioxidantes/metabolismo , Proteínas Aviárias/análise , Proteínas Aviárias/metabolismo , Cálcio/análise , Proteínas de Transporte/análise , Proteínas de Transporte/metabolismo , Cromatografia Líquida/veterinária , Eletroforese em Gel Bidimensional/veterinária , Fígado Gorduroso/enzimologia , Fígado Gorduroso/metabolismo , Perfilação da Expressão Gênica/veterinária , Fígado/química , Fígado/enzimologia , Masculino , Doenças das Aves Domésticas/enzimologia , Biossíntese de Proteínas , Proteoma/análise , Espectrometria de Massas por Ionização por Electrospray/veterinária , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/veterinária
19.
Poult Sci ; 90(10): 2360-9, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21934021

RESUMO

The present study was designed to evaluate the effect of preslaughter transport (30 vs. 150 min) and holding of mule ducks in lairage in their transport crates (15 vs. 120 min) on the quality of the meat and fatty liver. A total of 120 birds were allocated in a 2 × 2 factorial design with a constant postprandial delay to slaughter (8 h), to avoid the confounding between the effects of the experimental treatments and those of fasting duration. Under such conditions, extending the transport or holding duration did not induce a loss in preslaughter live weight or liver weight. Similarly, breast muscle glycogen stores were not affected by the treatments, nor was the kinetics of postmortem pH decline affected. The mechanical resistance of raw meat obtained by the compression test significantly increased with holding duration. The gross chemical composition of the livers did not differ significantly among the preslaughter treatments. Residual blood in the liver, as indicated by heme pigment concentration, was enhanced with a longer transport, but this effect was more pronounced after the longest holding duration, as shown by a significant interaction. This, however, did not significantly affect the incidence of appearance defects or the commercial grading of the livers. The percentage of fat loss during the cooking of canned livers was significantly reduced when the transport duration was increased. This effect could not be explained on the basis of the current knowledge for determining the technological quality of fatty liver. The identification of biological markers of liver quality is currently underway in our laboratory. Further investigations studying the differential expression of these biological markers according to preslaughter conditions would provide a better understanding of the effect of transport duration on liver processing yield.


Assuntos
Gorduras na Dieta/análise , Patos , Fígado/química , Carne/análise , Músculo Esquelético/química , Matadouros , Animais , Glicogênio/análise , Masculino , Período Pós-Prandial , Controle de Qualidade , Fatores de Tempo , Meios de Transporte
20.
Meat Sci ; 89(4): 377-83, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21621925

RESUMO

Fat loss during cooking of duck "foie gras" is the main quality issue in processing plants. To better understand this phenomenon, a histological and ultrastructural study was conducted. The aim was to characterize changes in lipid droplets of duck "foie gras" related to fat loss during cooking. Ten fatty livers were sampled before and after cooking and prepared for optical and transmission electron microscopy. In raw livers, the lipid droplets were nearly spherical while after cooking, they were larger and lost their spherical shape. We also observed a decrease in the number of droplets after cooking, probably due to droplet fusion caused by the heat treatment. Before cooking, there were fewer lipid droplets and a higher osmium tetroxyde staining intensity in the fatty liver, which later gave a lower technological yield. Fat loss during cooking was higher when there was more fusion of lipid droplets before cooking.


Assuntos
Culinária , Patos , Gorduras/química , Carne , Animais , Gorduras/análise , Temperatura Alta , Fígado/química , Microscopia Eletrônica de Transmissão , Microscopia de Fluorescência , Tetróxido de Ósmio , Coloração e Rotulagem
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