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1.
Phys Chem Chem Phys ; 25(42): 28703-28715, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37849351

RESUMO

Extracting reliable information on certain physical properties of materials, such as thermal transport, can be computationally very demanding. Aiming to overcome such difficulties in the particular case of lattice thermal conductivity (LTC) of 2D nanomaterials, we propose a simple, fast, and accurate semi-empirical approach for LTC calculation. The approach is based on parameterized thermochemical equations and Arrhenius-like fitting procedures, thus avoiding molecular dynamics or ab initio protocols, which frequently require computationally expensive simulations. As a proof of concept, we obtain the LTC of some prototypical physical systems, such as graphene (and other 2D carbon allotropes), hexagonal boron nitride (hBN), silicene, germanene, binary, and ternary BNC lattices and two examples of the fullerene network family. Our obtained values are in good agreement with other theoretical and experimental estimations, nonetheless, being derived in a rather straightforward way, at a fraction of the usual computational cost.

2.
J Mech Behav Biomed Mater ; 144: 105993, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37385128

RESUMO

Hydroxyapatite (HA) from bovine bones has been used as a biomaterial in dentistry due to its biocompatibility and bioactivity. However, dense HA bioceramics still present inadequate properties for applications that require high mechanical performance, such as infrastructure. Microstructural reinforcements and control of ceramic processing steps are methods to improve these shortcomings. The present study assessed the effects of polyvinyl butyral (PVB) addition in combination with two sintering methodologies (2-step and conventional), on the mechanical properties of polycrystalline bovine HA bioceramics. The samples were divided into four groups (with 15 samples per group): conventional sintering with binder (HBC) and without binder (HWC) and 2-step sintering with (HB2) and without binder (HW2). HA was extracted from bovine bones, turned into nanoparticles in a ball mill, and subjected to uniaxial and isostatic pressing into discs, according to ISO 6872 standards. All groups were characterized by x-ray diffractometry (XRD), differential thermal analysis (DTA) and Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and relative density. Besides, mechanical analyses (biaxial flexural strength (BFS) and modulus of elasticity) were also performed. The characterization results demonstrated that adding agglutinants or the sintering method did not affect HA's chemical and structural characteristics. Even so, the HWC group showed the highest mechanical values for BFS and modulus of elasticity being 109.0 (98.0; 117.0) MPa and 105.17 ± 14.65 GPa, respectively. The HA ceramics submitted to conventional sintering and without the addition of binders achieved better mechanical properties than the other groups. The impacts of each variable were discussed and correlated to the final microstructures and mechanical properties.


Assuntos
Durapatita , Nanopartículas , Animais , Bovinos , Durapatita/química , Materiais Biocompatíveis/química , Espectroscopia de Infravermelho com Transformada de Fourier , Cerâmica/química , Propriedades de Superfície , Teste de Materiais
3.
Arq. bras. med. vet. zootec. (Online) ; 71(6): 1815-1820, Nov.-Dec. 2019. ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1055132

RESUMO

The biological behaviour of the tumours vary according to the species in which they occur, its location within the cavity, clinical stage and histopathological nature. Lingual neoplasms are generally uncommon in companion animals. Rhabdomyosarcomas are malignant, solid, aggressive formations with high metastatic potential. The clinical signs are variable and a definitive diagnosis can only be reached through histopathological analysis of biopsy and necropsy specimen. In some cases, immunohistochemical study may be needed to confirm the diagnosis. This paper aims to highlight important points about this uncommon condition in dogs, using a case report of lingual rhabdomyosarcoma, which showed no evidence of metastasis after diagnosis, nor of local recurrence after surgical excision with a wide safety margin. It was concluded that early diagnosis, the correct interpretation of the complementary tests and the appropriate therapeutic approach contributed to improving the quality of life and survival of the patient in question.(AU)


O comportamento biológico dos tumores varia de acordo com a espécie animal, a localização na cavidade, a fase clínica e a natureza histopatológica. As neoplasias orais são geralmente incomuns em animais de companhia. Os rabdomiossarcomas são formações malignas, sólidas e agressivas, com alto potencial metastático. Os sinais clínicos são variáveis e o diagnóstico definitivo só pode ser alcançado por meio da análise histopatológica do material colhido. Em alguns casos, o estudo imuno-histoquímico pode ser necessário para confirmar o diagnóstico. Este trabalho tem como objetivo destacar pontos importantes sobre essa condição incomum em cães, utilizando um relato de caso de rabdomiossarcoma lingual, no qual não se evidenciaram metástases após o diagnóstico, nem recorrência local após a excisão cirúrgica com ampla margem de segurança. Concluiu-se que o diagnóstico precoce, a correta interpretação dos exames complementares e a abordagem terapêutica adequada contribuíram para melhorar a qualidade de vida e a sobrevida do paciente em questão.(AU)


Assuntos
Animais , Cães , Rabdomiossarcoma/patologia , Rabdomiossarcoma/terapia , Rabdomiossarcoma/veterinária , Neoplasias da Língua/veterinária
4.
Arq. bras. med. vet. zootec. (Online) ; 71(6): 1961-1967, Nov.-Dec. 2019. ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1055138

RESUMO

In view of the scarcity of data about the topography and syntopy of abdominopelvic viscera of the giant anteater (Myrmecophage tridactyla - Linnaeus, 1758), the present study aimed to elucidate these characteristics and to compare them with the other animal species, especially the domestic ones. Three specimens, two males and one female, were donated by the Environmental Military Police of Franca to the Anatomy Veterinary Laboratory of the University of Franca, after death by road killings. The animals were fixed and maintained in aqueous 10% formaldehyde solution, followed by conventional dissection of the abdominopelvic cavities for subsequent direct inspection and topographic description of the viscera, aiming at comparative analyzes with other species, whose positioning and particularities are already established in the literature. It was observed that most of the viscera of these cavities have similar location and syntopy to domestic animals, except for the kidneys and testicles. In view of the established methodology and the results obtained, it is accepted that more specimens of anteater, both genera, should be evaluated and registered scientifically to confirm the data of the current research and anatomical preconization of the abdominopelvic cavity, inasmuch anatomical individual variation are possible between animals of the same species.(AU)


Diante da escassez de dados sobre a topografia e a sintopia das vísceras abdominopélvicas do tamanduá-bandeira (Myrmecophage tridactyla - Linnaeus, 1758), o presente estudo teve como objetivo elucidar essas características e compará-las com as demais espécies animais, mormente as domésticas. Utilizaram-se três espécimes, dois machos e uma fêmea, provenientes de doação da Polícia Militar Ambiental de Franca ao Laboratório de Anatomia Veterinária da Universidade de Franca, após óbitos por atropelamentos. Os animais foram fixados e mantidos em solução aquosa de formaldeído a 10%, seguidos de dissecação convencional das cavidades abdominopélvicas para posterior inspeção direta e descrição topográfica das vísceras, visando a análises comparativas com outras espécies, cujo posicionamento e cujas particularidades já são bem estabelecidos na literatura. Observou-se que a maioria das vísceras dessas cavidades possuem localização e sintopia similares aos animais domésticos, exceto os rins e os testículos. Diante da metodologia estabelecida e dos resultados obtidos, admite-se que mais espécimes de tamanduás-bandeiras, de ambos os gêneros, devam ser avaliados e registrados cientificamente, visando à confirmação dos dados da atual pesquisa e à preconização anatômica da cavidade abdominopélvica, visto que variações anatômicas individuais são passíveis entre animais da mesma espécie.(AU)


Assuntos
Animais , Vísceras/anatomia & histologia , Cavidade Abdominal/anatomia & histologia , Xenarthra/anatomia & histologia
5.
Arq. bras. med. vet. zootec. (Online) ; 71(4): 1364-1374, jul.-ago. 2019. tab, graf
Artigo em Português | LILACS, VETINDEX | ID: biblio-1038613

RESUMO

Desde tempos remotos, a pelagem é valorizada no agronegócio equestre. Em animais Campolina, objetivou-se avaliar a ocorrência de pelagens e a distribuição entre sexos nos estados do Brasil, assim como verificar a frequência desse fenótipo nos acasalamentos e associá-lo com medidas lineares e qualidade da marcha. Foram selecionados 44.437 registros definitivos e utilizaram-se testes de qui-quadrado para avaliar a distribuição de pelagens entre sexos, estados e décadas. Por análise descritiva, foi obtida frequência de acasalamento dos fenótipos e proporções resultantes nos filhos. Foram contabilizados os indivíduos acasalados e os mais usados por décadas de nascimento e de registro. Pelagens baia, alazã e castanha predominaram, com 20.422; 11.941 e 5.256 animais, respectivamente. O fenótipo baio representou 45,21% em Minas Gerais; 46,98% no Rio de Janeiro e 48,98% em São Paulo. Para machos e fêmeas constatou-se maior frequência de pelagens baia, alazã e castanha. Os acasalamentos mais frequentes foram alazã x baia, baia x baia e baia x castanha. Este é o primeiro artigo a avaliar a ocorrência das pelagens em equinos da raça Campolina, sendo baia a mais prevalente em ambos os sexos. A qualidade da marcha ao registro não está associada à pelagem. Esse fenótipo deve ser usado com cautela na seleção.(AU)


Since ancient times, coat colors are valued in the equestrian business. The objective of this study was to evaluate the occurrence of coat colors and distribution among sexes in Brazil and also verify the frequency of this phenotype in reproduction to associate it with linear measurements and functionality. 44,437 definitive records were selected, and chi-square tests were used to evaluate coat colors and distribution between sexes, states and decades. By descriptive analysis the phenotypes breeding frequency and proportions in the offspring were obtained. Breeding and most used individuals were accounted by decade of birth and registration. Dun, chestnut and bay coat colors predominated, with 20,422; 11,941 and 5,256 animals, respectively. Dun represented 45.21% in Minas Gerais; 46.98% in Rio de Janeiro and 48.98% in São Paulo. For males and females there was a higher frequency of dun, chestnut and bay. The most frequent breeding colors were chestnut x dun, dun x dun and dun x bay. This is the first article to evaluate the coat colors in the Campolina population, dun being the most prevalent coat color in both sexes. The gait quality at the register is not associated with the coat color. This phenotype should be used with caution in selection.(AU)


Assuntos
Animais , Fenótipo , Pelo Animal/anatomia & histologia , Frequência do Gene , Cavalos
6.
RSC Adv ; 8(44): 24847-24856, 2018 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-35542156

RESUMO

Interest in hybrid monolayers with arrangements that differ from that of the honeycomb lattice has been growing. However, systematic investigations on the properties of these structures are still lacking. In this work, we combined density functional theory (DFT) and molecular dynamics (MD) simulations to study the stability and electronic properties of nanosheets composed of B, C, and N atoms arranged in the pattern of the carbon allotrope graphenylene. We considered twenty structures with varied atomic arrangements and stoichiometries, which we call B x C y N z hybrid graphenylenes. We calculated the formation energy for each arrangement, and found that it decreases as the number of B-C and N-C bonds decreases. We also found that the structure with minimum energy has stoichiometry B2CN and an atomic arrangement with BN and C stripes connected along the zigzag direction. Regarding the electronic properties, we found that all investigated structures are semiconductors, with band gaps ranging from 0.14 to 1.65 eV. Finally, we found that the optimized hybrid lattices presented pores of varied sizes and shapes. This diversity in pore geometry suggests that these structures might be particularly suited for molecular sieve applications.

7.
Arq. bras. med. vet. zootec. (Online) ; 70(5): 1423-1426, set.-out. 2018. ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-946884

RESUMO

The larynx is part of the upper respiratory tract and is responsible for phonation. It allows air to pass between the pharynx and the trachea, but prevents food from entering the airways. Laryngeal neoplasms, including rhabdomyosarcomas, are uncommon in dogs. However, these tumors can trigger numerous progressive clinical signs related to respiratory difficulty and altered phonation. The diagnosis of laryngeal cancer should be made based on the history and symptoms of the patient, combined with complementary tests. The treatment of choice is surgical excision, combined or not with chemotherapy. In view of the low incidence of laryngeal cancer, the objective of the present work was to describe a case of laryngeal rhabdomyosarcoma detected during necropsy of an adult dog and diagnosed by histopathology, in addition to raising awareness about the importance of the diagnosis and early therapy for the quality of life and survival of affected patients. The results showed that the location of the tumor impaired its early diagnosis. Although malignant, the animal did not develop metastases as has been described in the literature.(AU)


A laringe é um dos órgãos que compõem o trato respiratório superior, sendo também responsável pela fonação. Permite a passagem do ar entre a faringe e traqueia, mas impede que alimentos adentrem as vias aéreas. As neoplasias laringeanas, incluindo os rabdomiossarcomas, são incomuns em cães, porém, quando presentes, desencadeiam inúmeros sinais clínicos progressivos relacionados à dificuldade respiratória e à alteração na fonação. O diagnóstico das neoplasias na laringe deve ser baseado no histórico e na sintomatologia do paciente, associado a exames complementares. O tratamento de eleição é a exérese cirúrgica, concomitante ou não com a quimioterapia. Desse modo, diante da baixa incidência desse tipo neoplásico, inclusive na laringe, o objetivo do atual trabalho é descrever o caso de rabdomiossarcoma em laringe, detectado durante o exame de necropsia de um cão adulto e diagnosticado por histopatologia, bem como conscientizar sobre a importância do diagnóstico e da terapêutica precoce na qualidade de vida e sobrevida dos afetados. De acordo com a descrição do caso, pode-se admitir que a localização da neoplasia prejudicou o diagnóstico precoce e que, apesar de esta ser maligna, não houve metástases conforme descrição na literatura.(AU)


Assuntos
Animais , Cães , Laringe/anormalidades , Rabdomiossarcoma/classificação , Oncologia/classificação , Sistema Respiratório
8.
Arq. bras. med. vet. zootec. (Online) ; 69(4): 915-920, jul.-ago. 2017.
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-876684

RESUMO

The aim of this study was to analyze for 120 days, post-operative complications following bimanual phacoemulsification with implantation of hydrophilic or hydrophobic intraocular acrylic lens. The hospital records of 15 dogs were analyzed, and distributed in two groups, being Gfi and Gfo the hydrophilic intraocular lens and hydrophobic intraocular lens group, respectively. On the first day, both groups presented blepharospasm, conjunctival hyperemia and flare. On day 1, fibrin was slightly apparent in two and three eyes of Gfi and Gfo, and on day 7, present in one and two patients from Gfi and Gfo. Synechia was observed on day 1 in one eye from Gfi and Gfo. Two eyes from Gfi developed from 7 to 120 days, and in Gfo, one eye developed from 7 to 90 days, on day 120, two eyes formed them. The presence of posterior capsule opacity of the lens in all periods, there was no statistical significant between the groups. Only one eye, in Gfo, that had no opacity formation. The intraocular pressure of both groups remained within normal range. There was no statistical significance between hydrophilic and hydrophobic intraocular lens, the use of intraocular lens has led to satisfactory results in visual ability.(AU)


Objetivou-se com o presente estudo avaliar por 120 dias as complicações após a facoemulsificação bimanual com implantação de lentes acrílicas hidrofílicas ou hidrofóbicas. Os prontuários de 15 cães foram avaliados, sendo distribuídos em dois grupos, Gfi e Gfo, grupos com lentes intraoculares hidrofílicas e com lentes hidrofóbicas, respectivamente. No primeiro dia, ambos os grupos apresentaram blefarospasmo, hiperemia conjuntiva e flare. No dia 1, fibrina foi discretamente observada em dois e três olhos do Gfi e Gfo; no dia 7, observou-se em um e três olhos nos pacientes do Gfi e Gfo. Foi observada sinéquia no dia 1 em um olho do Gfi e do Gfo; em dois olhos do Gfi ocorreu do dia 7 ao dia 120. No Gfo apenas um olho teve sinéquia do dia 7 ao dia 90, contudo aos 120 dias, dois olhos formaram-na. A opacidade de cápsula posterior da lente esteve presente em todos os períodos, não havendo diferença estatística entre os grupos. Somente um olho, do Gfo, não teve formação de opacidade. A pressão intraocular foi normal em ambos os grupos. Não houve diferença estatística entre as lentes hidrofílicas e hidrofóbicas. O uso de lentes intraoculares apresentaram resultados satisfatórios na acuidade visual.(AU)


Assuntos
Animais , Cães , Catarata/veterinária , Lentes de Contato Hidrofílicas/veterinária , Implante de Lente Intraocular/veterinária , Facoemulsificação/veterinária , Oftalmopatias/complicações
9.
Animal ; 11(8): 1259-1269, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28077192

RESUMO

Probiotic administration can be a nutritional strategy to improve the immune response and growth performance of fish. The current study aimed to evaluate the effects of a probiotic blend (Bacillus sp., Pediococcus sp., Enterococcus sp., Lactobacillus sp.) as a dietary supplement on growth performance, feed utilization, innate immune and oxidative stress responses and intestinal morphology in juvenile Nile tilapia (Oreochromis niloticus). The probiotic was incorporated into a basal diet at three concentrations: 0 g/kg (A0: control), 3 g/kg (A1: 1.0×106 colony forming unit (CFU)/g) and 6 g/kg (A2: 2.3×106 CFU/g diet). After 8 weeks of probiotic feeding, weight and specific growth rate where significantly higher in fish-fed A1 diet than in fish-fed A0. Alternative complement in plasma was significantly enhanced in fish-fed A2 when compared with A0. The hepatic antioxidant indicators were not affected by probiotic supplementation. Villi height and goblet cell counts increased significantly in the intestine of fish-fed A1 and A2 diets compared with A0. The dietary probiotic supplementation was maintained until 20 weeks of feeding. Then the selected immune parameters, digestive enzymes and apparent digestibility of diets were studied. No effect of probiotic feeding was observed after that longer period supplementation. The dietary supplementation of mixed species probiotic may constitute a valuable nutritional approach towards a sustainable tilapia aquaculture. The improvement of the immune responses and intestinal morphology play an important role in increasing growth performance, nutrient absorption and disease resistance in fish, important outcomes in such a competitive and developing aquaculture sector.


Assuntos
Ração Animal , Ciclídeos/crescimento & desenvolvimento , Suplementos Nutricionais , Probióticos/administração & dosagem , Animais , Aquicultura , Ciclídeos/anatomia & histologia , Ciclídeos/imunologia , Dieta/veterinária , Imunidade , Intestinos/anatomia & histologia , Masculino
10.
Lett Appl Microbiol ; 63(3): 210-4, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27341694

RESUMO

UNLABELLED: Dekkera bruxellensis hit the spotlight in the past decade mostly due to its rather high ability to adapt to several different fermentation processes. This yeast relies on different genetic and physiological aspects to achieve and preserve its high industrial fitness and some of these traits are shared with Saccharomyces cerevisiae. We have previously described that D. bruxellensis is unable to make use of accumulating trehalose as a strategy for cell adaptation and survival in the industrial scenario, as opposed to S. cerevisiae. Since trehalose is often involved in mechanisms related to cell protection, we aimed to investigate both cause and effect of the absence of this metabolite in the cell adaptive capacity in the industrial environment. Our results indicate that the major cause for the nonaccumulation of trehalose is the high constitutive activity of neutral trehalase. Therefore, the rate of trehalose degradation could be higher than its rate of synthesis, preventing accumulation. Altogether, our data elucidate the mechanisms involved in the lack of trehalose accumulation in D. bruxellensis as well as evaluates the implications of this feature. SIGNIFICANCE AND IMPACT OF THE STUDY: Dekkera bruxellensis can successfully take advantage of its peculiar physiological and genetic traits in order to adapt and survive in fermentation processes. So far, tolerance to stress has been credited to trehalose synthesis. The data presented in this work provided information on the underlying mechanism that prevents trehalose accumulation and corroborated the recent information that trehalose itself is not implicated in yeast stress tolerance. Second, it showed that D. bruxellensis responds differently to Saccharomyces cerevisiae to excess of sugar, which may explain its preference for respiration (oxidative metabolism) over fermentation (reductive metabolism) even at limited oxygen supply. These findings help to understand the drop on ethanol production in processes overtaken by this yeast.


Assuntos
Dekkera/enzimologia , Dekkera/metabolismo , Saccharomyces cerevisiae/metabolismo , Trealase/metabolismo , Trealose/metabolismo , Metabolismo dos Carboidratos , Carboidratos , Dekkera/genética , Etanol/metabolismo , Fermentação/genética , Microbiologia Industrial/métodos , Fosforilação Oxidativa , Oxigênio/metabolismo
11.
Poult Sci ; 95(9): 2081-9, 2016 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-26976902

RESUMO

The energy and phosphorus values of sunflower meal (SFM) and rice bran (RB) were determined in 2 experiments with Ross 708 broiler chickens from 15 to 22 d of age. In Exp.1, the diets consisted of a corn-soybean meal reference diet (RD) and 4 test diets (TD). The TD consisted of SFM and RB that partly replaced the energy sources in the RD at 100 or 200 g/kg and 75 or 150 g/kg, respectively, such that the equal ratios were maintained for all energy containing ingredients across all experimental diets. In Exp.2, a cornstarch-soybean meal diet was the RD and TD consisting of SFM and RB that partly replaced cornstarch in the RD at 100 or 200 g/kg and 60 or 120 g/kg, respectively. Addition of SFM and RB to the RD in Exp.1 linearly decreased (P < 0.01) the digestibility coefficients of DM, energy, ileal digestible energy (IDE), metabolizability coefficients of DM, nitrogen (N), energy, N correct energy, metabolize energy (ME), and nitrogen-corrected ME. Except for RB, the increased levels of the test ingredients in RD did affect the metabolizability coefficients of N. The IDE values (kcal/kg DM) were 1,953 for SFM and 2,498 for RB; ME values (kcal/kg DM) were 1,893 for SFM and 2,683 for RB; and MEn values (kcal/kg DM) were 1,614 for SFM and 2,476 for RB. In Exp.2, there was a linear relationship between phosphorus (P) intake and ileal P output for diets with increased levels of SFM and RB. In addition, there was a linear relationship between P intake and P digestibility and retention for diets with increased levels of SFM. There were a quadratic effect (P < 0.01) and a tendency of quadratic effect (P = 0.07) for P digestible and total tract P retained, respectively, in the RB diets. The P digestibility and total tract P retention from regression analyses for SFM were 46% and 38%, respectively.


Assuntos
Fenômenos Fisiológicos da Nutrição Animal , Galinhas/fisiologia , Dieta/veterinária , Helianthus/química , Valor Nutritivo , Oryza/química , Ração Animal/análise , Animais , Digestão , Ingestão de Energia , Metabolismo Energético , Íleo/metabolismo , Masculino , Fósforo/metabolismo , Análise de Regressão
12.
Genet Mol Res ; 14(1): 2399-412, 2015 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-25867386

RESUMO

Cytochrome P450s (P450s) comprise a gene superfamily encoding enzymes that are involved in diverse plant metabolic pathways that produce primary and secondary metabolites such as phenylpropanoids, terpenoids, nitrogen-containing compounds, and plant hormones. They comprise one of the most diverse gene families in plant evolution. Although there are many studies that aim to characterize P450s in plants, there is no report on the characterization of this superfamily in Coffea arabica, where they might be related to plant tolerance to biotic and abiotic stresses, as well as aroma-related compounds. In this study, we report the characterization and annotation of 87 putative P450s from C. arabica obtained from the Brazilian Coffee Genome Project and describe their transcriptional pattern in different tissues and coffee organs. To validate our approach, we measured the transcriptional profile of the CaCYP81D8_1 gene by quantitative polymerase chain reaction in leaves, flowers, and fruits. This study is the first effort to present and analyze the P450 superfamily in C. arabica, which may assist in understanding the chemical diversity of coffee secondary metabolites.


Assuntos
Coffea/genética , Sistema Enzimático do Citocromo P-450/genética , Perfilação da Expressão Gênica , Família Multigênica , Proteínas de Plantas/genética , Coffea/enzimologia , Sistema Enzimático do Citocromo P-450/classificação , Regulação Enzimológica da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Isoenzimas/classificação , Isoenzimas/genética , Filogenia , Proteínas de Plantas/classificação , Reação em Cadeia da Polimerase Via Transcriptase Reversa
13.
Arq. bras. med. vet. zootec ; 67(2): 506-510, Mar-Apr/2015. tab
Artigo em Português | LILACS, VETINDEX | ID: lil-747049

RESUMO

Objetivou-se a avaliação dos efeitos dos níveis de suplementação de vitamina E na ração para frangos de corte sobre o desempenho na fase inicial (um a 21 dias de idade) e de crescimento (21 a 39 dias de idade). Os tratamentos foram definidos pelos níveis de suplementação de vitamina E (DL-α tocoferol). As quantidades adicionadas às rações foram: 10; 30; 50; 75 e 100mg de vitamina E para cada kg de ração. Na fase inicial (experimento I), o menor nível de suplementação de vitamina E mostrou-se superior aos demais, apresentando efeito significativo (P≤0,05) sobre o peso médio aos 21 dias de idade e ganho de peso de um a 21 dias de idade. Na fase de crescimento (experimento II), não houve efeito significativo (P>0,05) dos níveis de suplementação de vitamina E sobre as variáveis estudadas. O nível mínimo de suplementação de vitamina E testado (10mg/kg) é suficiente para atender às exigências dos frangos de corte machos sobre o desempenho.(AU)


This study aimed to evaluate the effect of vitamin E supplementation on the performance of broiler chickens in the initial and growth phase, from one to 21 and 21 to 39 days of age, respectively. Five increasing levels of DL-α tocopherol supplementation (10, 30, 50, 75 and 100mg to each kg of diet) were added to the diet. In the initial phase (experiment I), the lowest vitamin E level was superior by presenting significant effect (P≤0.05) on body weight at 21 days of age and weight gain from one to 21 days old. In the growth phase (experiment II), there was no significant effect (P>0.05) of vitamin E supplementation on the variables studied. The minimum level of vitamin E supplementation tested is sufficient to attend the requirements of male broiler chickens.(AU)


Assuntos
Animais , Vitamina E/administração & dosagem , Aumento de Peso , Galinhas/crescimento & desenvolvimento , Suplementos Nutricionais , Tocoferóis , Ração Animal/análise
14.
Arq. bras. med. vet. zootec ; 67(2): 492-498, Mar-Apr/2015. tab
Artigo em Português | LILACS, VETINDEX | ID: lil-747034

RESUMO

Avaliaram-se os efeitos da protease sobre o coeficiente de metabolizabilidade dos nutrientes em dietas contendo farinha de penas (2,0% na fase inicial e 3,0% na fase de crescimento) para frangos de corte machos, Cobb(r), de um a 32 dias de idade. Foram alojadas 336 aves em gaiolas metálicas equipadas com bandeja para coleta total de excretas. Foi utilizado delineamento inteiramente ao acaso, em arranjo fatorial 2x2 (com e sem adição da enzima protease 0,05% e duas valorizações da matriz nutricional da enzima), sendo sete repetições por tratamento, de 12 aves cada. Observou-se, na fase inicial, maior CMPB (P≤0,05) para as aves que, independentemente da adição de protease, consumiram ração com valorização da matriz nutricional da enzima. Não houve efeito dos tratamentos sobre o CMMS e o CMEE (P>0,05). Na fase de crescimento, houve interação entre os tratamentos para as variáveis CMPB e CMEE. Os frangos alimentados com dieta valorizada sem adição de enzima (controle negativo) apresentaram melhores resultados (P≤0,05) para CMPB e CMEE. Nos tratamentos com enzima, o melhor CMEE (P≤0,05) foi obtido com o tratamento sem valorização da matriz nutricional (over the top). Conclui-se que níveis reduzidos e enzima sem valorização melhoram os coeficientes de metabolizabilidade dos nutrientes na fase adulta de frangos de corte.(AU)


This experiment aimed to evaluate the effects of protease on metabolization coefficient of nutrients, performance and slaughter yield from male Cobb(r) broilers fed diets with feather meal. Two experiments were carried out in a completely randomized design in a 2x2 factorial arrangement - with (0.05%) or without enzyme addition x considering or not the improvement of the nutritional value by protease, with seven replicates per treatment group. In experiment 1 the metabolization coefficient of dry matter (MCDM), crude protein (MCCP) and ether extract (MCEE) in initial (9-12-d-old) and growth (29-32-d-old) phase was evaluated. In the initial phase it was observed that regardless of enzyme addition, broiler chickens fed a diet considering improvement in nutritional value had higher MCCP (P≤0.05). However, MCDM and MCEE were not affected (P>0.05). In the growth phase, there were interactions between treatments for the variables MCCP and MCEE. The birds fed diets considering the improvement in nutritional value without enzyme (negative control) showed better results (P≤0.05) for MCCP and MCEE. In the treatments with enzyme, the best MCEE (P≤0.05) was observed in the treatment not considering the improvement in the nutritional value (over the top). Therefore, considering the improvement in the nutritional value and enzyme without considering the improvement in the nutritional value improves the coefficients of metabolization of nutrients in broiler chickens.(AU)


Assuntos
Animais , Peptídeo Hidrolases/administração & dosagem , Galinhas/metabolismo , Enzimas/administração & dosagem , Taxa de Depuração Metabólica
15.
Genet Mol Res ; 13(4): 10913-20, 2014 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-25526212

RESUMO

Coffee is one of the most important commodities in the world, and its production relies mainly on two species, Coffea arabica and Coffea canephora. Although there are diverse transcriptome datasets available for coffee trees, few research groups have exploited the potential knowledge contained in these data, especially with respect to fruit and seed development. Here, we present a comparative analysis of the transcriptomes of Coffea arabica and Coffea canephora with a focus on fruit development using publicly available expressed sequence tags (ESTs). Most of the fruit and seed EST data has been obtained from C. canephora. Therefore, we performed a fruit EST analysis of the 5 developmental stages of this species (18, 22, 30, 42, and 46 weeks after flowering) comprising 29,009 sequences. We compared C. canephora fruit ESTs to reference unigenes of C. canephora (7710 contigs and 8955 singletons) and C. arabica (15,656 contigs and 16,351 singletons). Additional analyses included functional annotation based on Gene Onthology, as well as an annotation using PlantCyc, a curated plant protein database. The Coffee Bean EST (CoffeebEST) is a public database available at http://bioinfo-02.cp.utfpr.edu.br/. This database represents an additional resource for the coffee scientific community, offering a user-friendly collection of information for non-specialists in coffee molecular biology to support experimental research on comparative and functional genomics.


Assuntos
Coffea/classificação , Coffea/genética , Biologia Computacional/métodos , Proteínas de Plantas/genética , Transcriptoma , Coffea/crescimento & desenvolvimento , Etiquetas de Sequências Expressas , Frutas/genética , Frutas/crescimento & desenvolvimento , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Anotação de Sequência Molecular , Análise de Sequência de DNA , Software
16.
Genetica ; 141(4-6): 217-26, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23677718

RESUMO

Most of the world's coffee production originates from Coffea arabica, an allotetraploid species with low genetic diversity and for which few genomic resources are available. Genomic libraries with large DNA fragment inserts are useful tools for the study of plant genomes, including the production of physical maps, integration studies of physical and genetic maps, genome structure analysis and gene isolation by positional cloning. Here, we report the construction and characterization of a Bacterial Artificial Chromosome (BAC) library from C. arabica Timor Hybrid CIFC 832/2, a parental genotype for several modern coffee cultivars. The BAC library consists of 56,832 clones with an average insert size of 118 kb, which represents a dihaploid genome coverage of five to sixfold. The content of organellar DNA was estimated at 1.04 and 0.5 % for chloroplast and mitochondrial DNA, respectively. The BAC library was screened for the NADPH-dependent mannose-6-phosphate reductase gene (CaM6PR) with markers positioned on four linkage groups of a partial C. arabica genetic map. A mixed approach using PCR and membrane hybridization of BAC pools allowed for the discovery of nine BAC clones with the CaM6PR gene and 53 BAC clones that were anchored to the genetic map with simple sequence repeat markers. This library will be a useful tool for future studies on comparative genomics and the identification of genes and regulatory elements controlling major traits in this economically important crop species.


Assuntos
Quimera , Cromossomos Artificiais Bacterianos , Coffea/genética , Biblioteca Gênica , Genótipo , Hibridização de Ácido Nucleico/métodos
17.
Rev. bras. plantas med ; 15(1): 41-46, 2013. ilus, tab
Artigo em Inglês | LILACS | ID: lil-669533

RESUMO

Most illnesses affecting the oral cavity are proven to have infectious origin. Several categories of chemical agents have been used in the chemical control of dental biofilm through strategies that aim at reducing bacterial adhesion and inhibiting the growth and the proliferation of microorganisms on the tooth surface. The use of plants in folk medicine and in Dentistry, as well as the spread of successful cases, has led to scientific exploration, resulting in chemical-pharmacological knowledge of thousands of plants. The present study aimed to evaluate the anti-adherence activity of Lippia sidoides Cham., comparing the results with those of 0.12% chlorhexidine by means of an in vitro simulation of dental biofilm. The studied bacterial strains were Streptococcus mutans, Streptococcus sanguinis and Lactobacillus casei, main responsible for the biofilm adherence. The studied extract was effective in inhibiting the adherence of Streptococcus mutans up to a concentration of 1:16, compared to Chlorhexidine. Lippia sidoides Cham extract showed anti-adherence effect on the major microorganisms responsible for dental biofilm consolidation.


É fato comprovado que a maior parte das doenças que acometem a cavidade bucal são de origem infecciosa. Várias categorias de agentes químicos têm sido utilizadas no controle químico do biofilme dental através de estratégias que visam a redução da adesão bacteriana, a inibição do crescimento, e a proliferação dos microrganismos na superfície do dente. A utilização das plantas pela medicina popular, seu uso na Odontologia e a divulgação dos êxitos, conduziram a exploração científica resultando no conhecimento químico-farmacológico de milhares de plantas. A presente pesquisa objetivou avaliar a atividade antiaderente da folha da Lippia sidoides Cham. comparando seus resultados com a Clorexidina 0,12%, através de uma simulação, in vitro, do biofilme dental. As linhagens bacterianas utilizadas na pesquisa foram o Streptococcus mutans, Streptococcus sanguinis, e o Lactobacillus casaram, principais responsáveis pela aderência do biofilme. O extrato estudado mostrou-se efetivo na inibição de aderência das bactérias ensaiadas até uma concentração de 1:16, sobre o Streptococcus mutans, sendo comparável à Clorexidina. O extrato da Lippia sidoides Cham. demonstrou efeito antiederente, sobre os principais microrganismos responsáveis pela consolidação do biofilme dental.


Assuntos
Odontologia Preventiva , Verbenaceae/efeitos adversos , Placa Dentária , Doenças Dentárias/fisiopatologia
18.
Genet Mol Res ; 11(3): 3186-97, 2012 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-23007997

RESUMO

Coffee quality is directly related to the harvest and post harvest conditions. Non-uniform maturation of coffee fruits, combined with inadequate harvest, negatively affects the final quality of the product. Pectin methylesterase (PME) plays an important role in fruit softening due to the hydrolysis of methylester groups in cell wall pectins. In order to characterize the changes occurring during coffee fruit maturation, the enzymatic activity of PME was measured during different stages of fruit ripening. PME activity progressively increased from the beginning of the ripening process to the cherry fruit stage. In silico analysis of expressed sequence tags of the Brazilian Coffee Genome Project database identified 5 isoforms of PME. We isolated and cloned a cDNA homolog of PME for further characterization. CaPME4 transcription was analyzed in pericarp, perisperm, and endosperm tissues during fruit development and ripening as well as in other plant tissues. Northern blot analysis revealed increased transcription of CaPME4 in the pericarp 300 days after flowering. Low levels of CaPME4 mRNAs were observed in the endosperm 270 days after flowering. Expression of CaPME4 transcripts was strong in the branches and lower in root and flower tissues. We showed that CaPME4 acts specifically during the later stages of fruit ripening and possibly contributes to the softening of coffee fruit, thus playing a significant role in pectin degradation in the fruit pericarp.


Assuntos
Hidrolases de Éster Carboxílico/genética , Coffea/crescimento & desenvolvimento , Coffea/genética , Frutas/crescimento & desenvolvimento , Frutas/genética , Regulação da Expressão Gênica de Plantas , Sequência de Aminoácidos , Northern Blotting , Hidrolases de Éster Carboxílico/química , Hidrolases de Éster Carboxílico/metabolismo , Coffea/enzimologia , Biologia Computacional , Sequência Conservada/genética , Etiquetas de Sequências Expressas , Frutas/enzimologia , Perfilação da Expressão Gênica , Regulação Enzimológica da Expressão Gênica , Biblioteca Gênica , Genes de Plantas/genética , Dados de Sequência Molecular , Filogenia
20.
Plant Biol (Stuttg) ; 13(3): 462-71, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21489097

RESUMO

As a first step towards understanding the physiological role and regulation of the expansin gene (EXP) family in Coffea arabica fruits during growth and maturation, we identified 11 expansin genes, nine belonging to the α-expansin family (EXPA), one EXLA and one EXLB, through in silico analysis of expressed sequence tags (ESTs). Within the α-expansin family, three isoforms were selected for detailed examination based on their high expression in coffee fruits or because they were specifically induced during different fruit developmental stages, according to the EST information. The expression patterns were analysed in different fruit tissues (perisperm, endosperm and pericarp) of C. arabica cv. IAPAR-59 and C. arabica cv. IAPAR-59 Graúdo, the latter being a closely related cultivar with a larger fruit size. Accumulation of CaEXPA1 and CaEXPA3 transcripts was high in the perisperm (tissue responsible for coffee bean size) and in the early stages of pericarp development. Transcripts of CaEXPA2 were detected only in the pericarp during the later stages of fruit maturation and ripening. There was no detectable transcription of the three EXPs analysed in the endosperm. The observed differences in mRNA expression levels of CaEXPA1 and CaEXP3 in the perisperm of IAPAR-59 and IAPAR-59 Graúdo suggest the participation of these two isoforms in the regulation of grain size.


Assuntos
Coffea/crescimento & desenvolvimento , Coffea/metabolismo , Frutas/crescimento & desenvolvimento , Frutas/metabolismo , Proteínas de Plantas/biossíntese , Coffea/genética , Etiquetas de Sequências Expressas , Frutas/genética , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Variação Genética , Proteínas de Plantas/genética , Isoformas de Proteínas , Sementes/genética , Sementes/metabolismo , Ativação Transcricional
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