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1.
J Neurol Surg B Skull Base ; 83(6): 561-578, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36393883

RESUMO

Hospitals, payors, and patients increasingly expect us to report our outcomes in more detail and to justify our treatment decisions and costs. Although there are many stakeholders in surgical outcomes, physicians must take the lead role in defining how outcomes are assessed. Skull base lesions interact with surrounding anatomy to produce a complex spectrum of presentations and surgical challenges, requiring a wide variety of surgical approaches. Moreover, many skull base lesions are relatively rare. These factors and others often preclude the use of prospective randomized clinical trials, thus necessitating alternate methods of scientific inquiry. In this paper, we propose a roadmap for implementing a skull base registry, along with expected benefits and challenges.

2.
Phys Rev E ; 104(6-1): 064120, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35030842

RESUMO

We revisit the associating lattice gas (ALG) introduced by Henriques et al. [Phys. Rev. E 71, 031504 (2005)PLEEE81539-375510.1103/PhysRevE.71.031504] in its symmetric version. In this model, defined on the triangular lattice, interaction between molecules occupying nearest-neighbor sites depends on their relative orientation, mimicking the formation of hydrogen bonds in network-forming fluids. Although all previous studies of this model agree that it has a disordered fluid (DF), a low-density liquid (LDL), and a high-density liquid (HDL) phase, quite different forms have been reported for its phase diagram. Here, we present a thorough investigation of its phase behavior using both transfer matrix calculations and Monte Carlo (MC) simulations, along with finite-size scaling extrapolations. Results in striking agreement are found using these methods. The critical point associated with the DF-HDL transition at full occupancy, identified by Furlan et al. [Phys. Rev. E 100, 022109 (2019)2470-004510.1103/PhysRevE.100.022109] is shown to be one terminus of a critical line separating these phases. In opposition to previous simulation studies, we find that the transition between the DF and LDL phases is always discontinuous, similar to the LDL-HDL transition. The associated coexistence lines meet at the point where the DF-HDL critical line ends, making it a critical-end-point. Overall, the form of the phase diagram observed in our simulations is very similar to that found in the exact solution of the model on a Husimi lattice. Our results confirm that, despite the existence of some waterlike anomalies in this model, it is unable to reproduce key features of the phase behavior of liquid water.

3.
J Appl Microbiol ; 130(5): 1671-1683, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-32979295

RESUMO

AIM: In this work, we evaluated the effects of light on growth, cell physiology and stress response of Azospirillum brasilense Az39, a non-photosynthetic rhizobacteria, under planktonic growth conditions. METHODS AND RESULTS: Exponential cultures of Az39 were exposed to blue (BL), red (RL) and daylight (DL) or maintained in darkness for 24, 48 and 72 h. The biomass production and indole 3-acetic acid (IAA) biosynthesis increased by exposition to DL. Conversely, BL decreased IAA concentration through a direct effect on the molecule. The DL increased superoxide dismutase activity, hydrogen peroxide and thiobarbituric acid reactive substances levels, but the last one was also increased by BL. Both DL and BL increased cell aggregation but only BL increased biofilm formation. CONCLUSIONS: We demonstrated that both BL and DL are stress effectors for A. brasilense Az39 under planktonic growth conditions. The DL increased biomass production, IAA biosynthesis and bacterial response to stress, whereas BL induced cell aggregation and biofilms formation, but decreased the IAA concentration by photooxidation. SIGNIFICANCE AND IMPACT OF THE STUDY: Blue light and DL changes growth capacity, cell physiology and plant growth promotion ability of A. brasilense Az39 and these changes could be considered to improve the production and functionality of biofertilizers.


Assuntos
Azospirillum brasilense/fisiologia , Peróxido de Hidrogênio/metabolismo , Ácidos Indolacéticos/metabolismo , Luz , Superóxido Dismutase/metabolismo , Tiobarbitúricos/metabolismo , Azospirillum brasilense/efeitos da radiação , Proteínas de Bactérias/metabolismo , Biofilmes , Sobrevivência Celular , Escuridão , Estresse Fisiológico
4.
Phys Rev E ; 100(2-1): 022109, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31574678

RESUMO

We study an associating lattice gas (ALG) using Monte Carlo simulation on the triangular lattice and semianalytical solutions on Husimi lattices. In this model, the molecules have an orientational degree of freedom and the interactions depend on the relative orientations of nearest-neighbor molecules, mimicking the formation of hydrogen bonds. We focus on the transition between the high-density liquid (HDL) phase and the isotropic phase in the limit of full occupancy, corresponding to chemical potential µâ†’∞, which has not yet been studied systematically. Simulations yield a continuous phase transition at τ_{c}=k_{B}T_{c}/γ=0.4763(1) (where -γ is the bond energy) between the low-temperature HDL phase, with a nonvanishing mean orientation of the molecules, and the high-temperature isotropic phase. Results for critical exponents and the Binder cumulant indicate that the transition belongs to the three-state Potts model universality class, even though the ALG Hamiltonian does not have the full permutation symmetry of the Potts model. In contrast with simulation, the Husimi lattice analyses furnish a discontinuous phase transition, characterized by a discontinuity of the nematic order parameter. The transition temperatures (τ_{c}=0.51403 and 0.51207 for trees built with triangles and hexagons, respectively) are slightly higher than that found via simulation. Since the Husimi lattice studies show that the ALG phase diagram features a discontinuous isotropic-HDL line for finite µ, three possible scenarios arise for the triangular lattice. The first is that in the limit µâ†’∞ the first-order line ends in a critical point; the second is a change in the nature of the transition at some finite chemical potential; the third is that the entire line is one of continuous phase transitions. Results from other ALG models and the fact that mean-field approximations show a discontinuous phase transition for the three-state Potts model (known to possess a continuous transition) lends some weight to the third alternative.

6.
Rev Mal Respir ; 35(8): 796-812, 2018 Oct.
Artigo em Francês | MEDLINE | ID: mdl-30174236

RESUMO

The mutations leading to MET exon 14 skipping represent a new class of molecular alterations described in various cancers. These alterations are observed in 2 to 3 % of cases of non-small cell lung cancer (NSCLC). Several cases of NSCLC carrying such alterations and achieving objective response to MET tyrosine kinase inhibitorshave recently been published. This review summarizes the molecular mechanisms responsible for MET exon 14 skipping as well as the consequences of the loss of this exon on receptor activity. We also describe the clinical characteristics of patients with METΔ14 mutations. Finally, we address the issues related to the detection of these mutations in lung cancer, and the need to anticipate resistance to MET inhibitors.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/terapia , Neoplasias Pulmonares/terapia , Terapia de Alvo Molecular , Mutação , Proteínas Proto-Oncogênicas c-met/genética , Sítios de Splice de RNA/genética , Processamento Alternativo/genética , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Éxons , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Terapia de Alvo Molecular/métodos , Terapia de Alvo Molecular/tendências , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Proto-Oncogênicas c-met/antagonistas & inibidores
7.
J Anim Physiol Anim Nutr (Berl) ; 102(2): e918-e930, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29250876

RESUMO

Two experiments were carried out to determine the levels of supplementation of inorganic selenium (Se) and vitamin E (VE) in diets of quails aged 0-14 and 14-35 days old. A completely randomized design was used in a factorial design (Se = 0.1125; 0.2250; 0.3375 and 0.4500 mg kg-1  diet-1  × VE = 10; 23; 36 and 49 IU kg-1  diet-1 ). In experiment 1, quail (n = 2,400) were aged 0-14 days and were divided into 16 treatments, with three replicates of 50 birds. In experiment 2, quail (n = 1,680) were aged 14-35 days and were divided into the same treatments, with three replicates of 35 birds. At age 0-14 days, the levels of VE did not affect performance (p > .05); however, the feed conversion (FC) was influenced by a quadratic effect (p = .0515), according to the level of Se, with a higher level estimated at 0.29 mg Se kg-1  diet-1 . At age 14-35 days, there was a linear effect with interaction (Se × VE), for FC (p = .0150) and weight gain (WG; p = .0266). FC (Se, p = .0048 and VE, p = .0019) and WG (Se, p = .0049 and VE, p = .0068) improved linearly with increasing levels of Se and VE. The feed intake (FI) decreased linearly (p = .0582) as a function of VE. The carcass yield showed a quadratic effect (p = .0056) on the levels of VE, with a higher yield estimation of 27.24 IU VE/kg of diet. It can be concluded that the optimum level of supplementation at age 0-14 days was 0.29 mg Se kg-1  diet-1 and 10 IU VE kg-1  diet-1 and at age 14-35 days, it was 0.4500 mg Se kg-1  diet-1 and 49 IU of VE kg-1  diet-1 .


Assuntos
Ração Animal/análise , Codorniz/crescimento & desenvolvimento , Ácido Selenioso/administração & dosagem , Vitamina E/administração & dosagem , Envelhecimento , Fenômenos Fisiológicos da Nutrição Animal , Animais , Dieta/veterinária , Suplementos Nutricionais
8.
Arq. bras. med. vet. zootec. (Online) ; 69(4): 1006-1012, jul.-ago. 2017. tab
Artigo em Português | LILACS, VETINDEX | ID: biblio-876728

RESUMO

O presente experimento foi realizado com o objetivo de determinar os níveis de suplementação de vitamina K para codornas de corte. O delineamento experimental foi inteiramente ao acaso, com oito tratamentos, cinco repetições e 38 codornas por unidade experimental. Os níveis de suplementação de vitamina K foram: 0; 0,7; 1,0; 1,3; 1,6; 1,9; 2,2; 2,5mg/kg de ração. Não houve influência dos níveis de suplementação de vitamina K sobre o consumo de ração, peso corporal, ganho de peso, biomassa corporal acumulada e conversão alimentar, como também não foram alterados o peso, a densidade óssea, a resistência óssea e a concentração de cinzas no fêmur e na tíbia, o comprimento e o índice de Seedor do fêmur e o diâmetro da tíbia. O diâmetro e a concentração de cálcio no fêmur bem como o comprimento e a concentração de cálcio na tíbia responderam de forma quadrática (P<0,05), sendo os melhores níveis encontrados de 1,33; 1,42; 1,59 e 1,42mg de vitamina K, respectivamente. O tempo de protrombina, a concentração de cálcio no soro e a fosfatase alcalina também não foram afetados significativamente. Conclui-se que os níveis de suplementação não influenciaram o desempenho, portanto rações à base de milho e farelo de soja são suficientes para atender às necessidades de vitamina K das codornas nessa fase.(AU)


An experiment was carried out in order to determine the levels of vitamin K for meat quails. The experimental design was completely randomized with 8 treatments, 5 repetitions and 38 quails per experimental unit. The levels of vitamin K supplementation were 0; 0.7; 1.0; 1.3; 1.6; 1.9; 2.2; 2.5 mg/kg diets. There was no influence in the levels of vitamin K supplementation on feed intake, body weight, weight gain, biomass accumulated body and feed conversion. It also didn't affect the weight, bone density, bone strength and concentration of ash in the femur and tibial, length, index of Seedor femur and tibial diameter. Femur diameter and femur calcium concentration and the tibial length and tibial calcium concentration showed a quadratic response, with the highest levels found 1.33; 1.42; 1.59 and 1.42 mg of vitamin respectively. Prothrombin time, concentration of serum calcium and alkaline phosphatase levels also were not significantly affected. In conclusion, levels of supplementation did not influence the performance of meat quails, so diets based on corn and soybean meal are sufficient to meet the needs of the meat quails at this stage.(AU)


Assuntos
Animais , Desenvolvimento Ósseo , Coturnix , Suplementos Nutricionais/estatística & dados numéricos , Vitamina K/administração & dosagem , Fenômenos Fisiológicos da Nutrição , Tempo de Protrombina/veterinária
9.
Ann Hematol ; 96(7): 1147-1153, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28451805

RESUMO

Several studies suggested that staging bone marrow biopsy (BMB) could be omitted in patients with classical Hodgkin's lymphoma (cHL) when a positron emission tomography/computed tomography (PET/CT) is performed at baseline.To address the concordance between BMB and PET/CT in the detection of bone marrow involvement (BMI) and the BMB role in determining the Ann Arbor stage, we retrospectively collected data on 1244 consecutive patients with cHL diagnosed from January 2007 to December 2013. One thousand eighty-five patients who had undergone both BMB and PET/CT were analyzed, comparing the Ann Arbor stage assessed with PET/CT only to that resulting from PET/CT combined with BMB.One hundred sixty-nine patients (16%) showed at least one focal skeletal lesion (FSL) at PET/CT evaluation. Only 55 patients had a positive BMB (5.1%); 34 of them presented at least one FSL at PET/CT. To the contrary, 895 out of 1030 patients with a negative BMB did not show any FSL (86.9%). Positive and negative predictive values of PET/CT for BMI were 20 and 98%, respectively; sensitivity and specificity were 62 and 87%, respectively. Fifty-four out of 55 patients with a positive BMB could have been evaluated as an advanced stage just after PET/CT; only one patient (0.1%) would have been differently treated without BMB.Our data showed a very high negative predictive value of PET/CT for BMI and a negligible influence of BMB on treatment planning, strengthening the recent indications that BMB could be safely omitted in cHL patients staged with PET/CT.


Assuntos
Exame de Medula Óssea/métodos , Doença de Hodgkin/diagnóstico por imagem , Estadiamento de Neoplasias/métodos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia , Medula Óssea/patologia , Feminino , Doença de Hodgkin/sangue , Doença de Hodgkin/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade , Adulto Jovem
10.
J Chem Phys ; 146(14): 144503, 2017 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-28411617

RESUMO

We perform an extensive computational study of binary mixtures of water and short-chain alcohols resorting to two-scale potential models to account for the singularities of hydrogen bonded liquids. Water molecules are represented by a well studied core softened potential which is known to qualitatively account for a large number of water's characteristic anomalies. Along the same lines, alcohol molecules are idealized by dimers in which the hydroxyl groups interact with each other and with water with a core softened potential as well. Interactions involving non-polar groups are all deemed purely repulsive. We find that the qualitative behavior of excess properties (excess volume, enthalpy, and constant pressure heat capacity) agrees with that found experimentally for alcohols such as t-butanol in water. Moreover, we observe that our simple solute under certain conditions acts as a "structure-maker," in the sense that the temperature of maximum density of the bulk water model increases as the solute is added, i.e., the anomalous behavior of the solvent is enhanced by the solute.

11.
Clin Radiol ; 72(1): 93.e1-93.e6, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27633725

RESUMO

AIM: To perform an intra-individual comparison of the frequency of respiratory-motion artefacts on magnetic resonance imaging (MRI) in cirrhotic patients following injection of gadoxetate disodium and gadobenate dimeglumine. MATERIALS AND METHODS: Ninety-five cirrhotic patients (61 men and 34 women, mean age 58 years) underwent liver MRI with intravenous administration of gadoxetate disodium and gadobenate dimeglumine at different times (interval between studies, 189±83 days). Three readers scored the severity of respiratory-motion artefacts on the three-dimensional (3D) gradient-echo (GRE) images acquired before and after contrast medium injection. McNemar's test was used to assess the difference in frequency of new respiratory-motion artefacts and transient severe motion (TSM) artefacts between gadoxetate disodium and gadobenate dimeglumine MRI studies. The association between clinical and technical features and the occurrence of TSM on gadoxetate disodium MRI studies was investigated. RESULTS: On arterial phase images, new respiratory-motion artefacts were present in 32/95 (34%) cases after injection of gadoxetate disodium, while only seen in 2/95 (2%) cases after injection of gadobenate dimeglumine (p<0.0001). TSM was present in 6/95 (6%) cases after injection of gadoxetate disodium, and in 0/95 (0%) case after injection of gadobenate dimeglumine. No clinical or technical features were associated with the occurrence of TSM. CONCLUSIONS: In cirrhotic patients, respiratory-motion artefacts on arterial phase 3D GRE images are more frequently seen after injection of gadoxetate disodium than after injection of gadobenate dimeglumine.


Assuntos
Artefatos , Gadolínio DTPA/administração & dosagem , Cirrose Hepática/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Meglumina/análogos & derivados , Compostos Organometálicos/administração & dosagem , Mecânica Respiratória , Meios de Contraste/administração & dosagem , Feminino , Humanos , Aumento da Imagem/métodos , Injeções Intravenosas , Fígado/diagnóstico por imagem , Estudos Longitudinais , Masculino , Meglumina/administração & dosagem , Pessoa de Meia-Idade , Movimento (Física) , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade
12.
J Chem Phys ; 145(14): 144501, 2016 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-27782509

RESUMO

A lattice model for the study of mixtures of associating liquids is proposed. Solvent and solute are modeled by adapting the associating lattice gas (ALG) model. The nature of interaction of solute/solvent is controlled by tuning the energy interactions between the patches of ALG model. We have studied three set of parameters, resulting in, hydrophilic, inert, and hydrophobic interactions. Extensive Monte Carlo simulations were carried out, and the behavior of pure components and the excess properties of the mixtures have been studied. The pure components, water (solvent) and solute, have quite similar phase diagrams, presenting gas, low density liquid, and high density liquid phases. In the case of solute, the regions of coexistence are substantially reduced when compared with both the water and the standard ALG models. A numerical procedure has been developed in order to attain series of results at constant pressure from simulations of the lattice gas model in the grand canonical ensemble. The excess properties of the mixtures, volume and enthalpy as the function of the solute fraction, have been studied for different interaction parameters of the model. Our model is able to reproduce qualitatively well the excess volume and enthalpy for different aqueous solutions. For the hydrophilic case, we show that the model is able to reproduce the excess volume and enthalpy of mixtures of small alcohols and amines. The inert case reproduces the behavior of large alcohols such as propanol, butanol, and pentanol. For the last case (hydrophobic), the excess properties reproduce the behavior of ionic liquids in aqueous solution.

13.
Arq. bras. med. vet. zootec ; 68(4): 1000-1006, jul.-ago. 2016. tab
Artigo em Português | LILACS, VETINDEX | ID: lil-792469

RESUMO

Foram conduzidos dois experimentos, com o objetivo de estimar a exigência de valina e isoleucina digestível para codornas de corte em crescimento. No experimento 1, foram utilizadas 2.160 codornas de corte de um dia de idade, não sexadas, distribuídas em um delineamento inteiramente ao acaso, com arranjo fatorial 4x4, sendo quatro níveis de valina digestível (0,90, 1,10, 1,30 e 1,50%) e quatro níveis de isoleucina digestível (0,80, 1,00, 1,20 e 1,40%), totalizando 16 tratamentos, com três repetições e 45 codornas por unidade experimental. O peso corporal, o ganho de peso e a biomassa corporal acumulada aumentaram linearmente em função dos níveis de valina digestível e foram influenciados de forma quadrática, estimando 1,38% de isoleucina digestível. No experimento 2, foram utilizadas 1.440 codornas de corte não sexadas, distribuídas em um delineamento inteiramente ao acaso, com arranjo fatorial 4x4, sendo quatro níveis de valina digestível (0,82, 1,02, 1,22 e 1,42%) e quatro níveis de isoleucina digestível (0,73, 0,93, 1,13 e 1,33%), totalizando 16 tratamentos, com três repetições e 30 codornas por unidade experimental. O desempenho de codornas de corte, no período de 15 a 35 dias de idade, não foi influenciado pelo aumento dos níveis de valina e isoleucina digestível nas rações experimentais. Conclui-se que as exigências de valina e isoleucina digestível para o máximo desempenho de codornas de corte, no período de um a 14 dias de idade, foram de 1,50% e 1,38%, respectivamente, correspondendo às relações valina:lisina de 95% e isoleucina:lisina de 88%. Os menores níveis avaliados, no período de 15 a 35 dias de idade, de 0,82% de valina digestível e de 0,73% de isoleucina digestível, correspondendo às relações valina:lisina de 52% e isoleucina: lisina de 46%, foram suficientes para satisfazer as exigências nutricionais das codornas de corte sem comprometer o desempenho.(AU)


Two experiments were carried out in order to estimate the requirements of digestible valine and isoleucine for growing meat quails. In experiment 1, 2160 meat quails with 1 day of age, not sexed, were used, distributed in a completely randomized design with a 4x4 factorial arrangement, with four levels of digestible valine (0.90, 1.10, 1.30, and 1.50%) and four levels of digestible isoleucine (0.80, 1.00, 1.20, and 1.40 %), totaling 16 treatments with three replications and 45 quails per experimental unit. The body weight, the weight gain, and the accumulated body biomass linearly increased in function of digestible valine levels and were influenced in a quadratic way estimating 1.38% of digestible isoleucine. In experiment 2, 1440 meat quails, not sexed, were used, distributed in a completely randomized design with a 4x4 factorial arrangement, with four levels of digestible valine (0.82, 1.02, 1.22, and 1.42%) and four levels of digestible isoleucine (0.73, 0.93, 1.13, and 1.33%), totaling 16 treatments with three replications and 30 quails per experimental unit. The performance of meat quails from 15 to 35 days of age was not affected by increased levels of digestible valine and digestible isoleucine in the experimental diets. It was concluded that the requirements of digestible valine and digestible isoleucine for maximum performance of meat quail from one to 14 days of age were 1.50% and 1.38%, respectively, corresponding to relations: valine: lysine of 95% and isoleucine: lysine of 88%. The lower levels evaluated, in the period of 15 to 35 days old, 0.82% digestible valine and 0.73% of digestible isoleucine, corresponding to relations valine: lysine of 52% and isoleucine: lysine of 46% were sufficient to meet the nutritional requirements of meat quails without compromising performance.(AU)


Assuntos
Animais , Aminoácidos , Ração Animal/análise , Coturnix , Isoleucina/administração & dosagem , Valina/administração & dosagem
14.
Abdom Radiol (NY) ; 41(2): 283-94, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26867910

RESUMO

Despite advances in multimodality imaging of pancreas, there is still overlap between imaging findings of several pancreatic/peripancreatic disease processes. Pancreatic and peripancreatic non-neoplastic entities may mimic primary pancreatic neoplasms on ultrasound, CT, and MRI. On the other hand, primary pancreatic cancer may be overlooked on imaging because of technical and inherent factors. The purpose of this pictorial review is to describe and illustrate pancreatic imaging pitfalls and highlight the basic radiological features for proper differential diagnosis.


Assuntos
Imagem Multimodal , Pancreatopatias/diagnóstico por imagem , Diagnóstico Diferencial , Humanos , Neoplasias Pancreáticas/diagnóstico por imagem
15.
Artigo em Inglês | MEDLINE | ID: mdl-26465479

RESUMO

The thermodynamic, dynamic, and structural behavior of a water-like system confined in a matrix is analyzed for increasing confining geometries. The liquid is modeled by a two-dimensional associating lattice gas model that exhibits density and diffusion anomalies, similar to the anomalies present in liquid water. The matrix is a triangular lattice in which fixed obstacles impose restrictions to the occupation of the particles. We show that obstacles shorten all lines, including the phase coexistence, the critical and the anomalous lines. The inclusion of a very dense matrix not only suppresses the anomalies but also the liquid-liquid critical point.

16.
Cell Death Dis ; 6: e1769, 2015 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-25996296

RESUMO

Upon activation by its ligand hepatocyte growth factor/scatter factor, the receptor tyrosine kinase Met promotes survival, proliferation, and migration of epithelial cells during embryogenesis. Deregulated Met signaling can also promote cancer progression and metastasis. Met belongs to the functional family of dependence receptors whose activity switches from pro-survival to pro-apoptotic during apoptosis upon caspase cleavage. Although apoptosis resistance is a hallmark of cancer cells, some remain sensitive to other cell death processes, including necrosis induced by calcium stress. The role and fate of Met during necrotic cell death are unknown. Following treatment with calcium ionophores, cell lines and primary cells undergo necrosis, and the full-length Met receptor is efficiently degraded. This degradation is achieved by double cleavage of Met in its extracellular domain by a metalloprotease of the A disintegrin and metalloproteinase (ADAM) family and in its intracellular domain by calpains (calcium-dependent proteases). These cleavages separate the Met extracellular region from its kinase domain, thus preventing Met activity and its potential pro-survival activity. Although the intracellular fragment is very similar to the fragment generated by caspases, it displays no pro-apoptotic property, likely because of the presence of the last few amino acids of Met, known to inhibit this pro-apoptotic function. The fragments identified here are observed in lung tumors overexpressing the Met receptor, along with fragments previously identified, suggesting that proteolytic cleavages of Met are involved in its degradation in tumor tissues. Thus, Met is a modulator of necrosis, able to protect cells when activated by its ligand but efficiently degraded by proteolysis when this process is engaged.


Assuntos
Apoptose/fisiologia , Neoplasias Pulmonares/patologia , Necrose/patologia , Proteínas Proto-Oncogênicas c-met/metabolismo , Proteínas ADAM/metabolismo , Animais , Apoptose/efeitos dos fármacos , Cálcio/metabolismo , Calpaína/metabolismo , Caspases/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Sobrevivência Celular , Ativação Enzimática , Células Epiteliais/metabolismo , Células HEK293 , Fator de Crescimento de Hepatócito/metabolismo , Humanos , Ionomicina/farmacologia , Camundongos , Metástase Neoplásica/patologia , Interferência de RNA , RNA Interferente Pequeno , Transdução de Sinais
17.
Cell Death Differ ; 22(11): 1754-63, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25744026

RESUMO

Nonsense-mediated mRNA decay (NMD) is an mRNA surveillance mechanism that plays integral roles in eliminating mRNAs with premature termination codons to prevent the synthesis of truncated proteins that could be pathogenic. One response to the accumulation of detrimental proteins is apoptosis, which involves the activation of enzymatic pathways leading to protein and nucleic acid cleavage and culminating in cell death. It is not clear whether NMD is required to ensure the accurate expression of apoptosis genes or is no longer necessary since cytotoxic proteins are not an issue during cell death. The present study shows that caspases cleave the two NMD factors UPF1 and UPF2 during apoptosis impairing NMD. Our results demonstrate a new regulatory pathway for NMD that occurs during apoptosis and provide evidence for role of the UPF cleaved fragments in apoptosis and NMD inhibition.


Assuntos
Caspases/metabolismo , Degradação do RNAm Mediada por Códon sem Sentido/fisiologia , Apoptose/genética , Apoptose/fisiologia , Western Blotting , Caspases/genética , Células HeLa , Humanos , Degradação do RNAm Mediada por Códon sem Sentido/genética , RNA Interferente Pequeno/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa
18.
Br Poult Sci ; 56(1): 6-14, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25490970

RESUMO

1. The objective of this study was to estimate growth parameters of carcass components (wing, thighs and drumsticks, back and breast) and organs (heart, liver, gizzard and gut) in males and females of one meat-type quail strain (Coturnix coturnix coturnix) and two laying strains (Coturnix coturnix japonica) designated either yellow or red. 2. A total of 1350 quail from 1 to 42 d old were distributed in a completely randomised design, with 5 replicates of each strain. The carcass component weights and body organs were analysed weekly and evaluated using the Gompertz function; growth rates were evaluated through derivative equations. 3. The meat-type strain presented the highest growth rates in carcass components and organs. Across strains, females showed the highest weight of internal organs at maturity compared to males. 4. Females had greater growth potential in breast, wings and back than males for both yellow and red laying quail.


Assuntos
Composição Corporal , Coturnix/crescimento & desenvolvimento , Animais , Coturnix/genética , Feminino , Masculino , Carne , Modelos Biológicos , Tamanho do Órgão , Fatores Sexuais
19.
Arq. bras. med. vet. zootec ; 66(5): 1547-1556, Sep-Oct/2014. tab, graf
Artigo em Português | LILACS | ID: lil-729777

RESUMO

Três experimentos foram conduzidos para determinar o valor nutritivo da glicerina bruta (GB), bem como verificar o desempenho de codornas de corte alimentadas com essa fonte alternativa de alimento. No experimento I, foram utilizadas 75 codornas, distribuídas em delineamento inteiramente ao acaso (DIC), com três tratamentos e cinco repetições. Os tratamentos consistiram de uma ração referência (RR) e duas rações teste (RT), e a GB substituiu a RR em níveis de oito e 12%. O valor estimado de energia metabolizável aparente corrigida para balanço de nitrogênio (EMAn) foi de 4.893kcal/kg. No experimento II, de um a 14 dias de idade, foram utilizadas 1.320 codornas, não sexadas, distribuídas em DIC, com seis tratamentos e quatro repetições. Os tratamentos foram constituídos por seis rações com níveis crescentes (0, 3, 6, 9, 12 e 15%) de GB. O peso vivo (PV), o ganho de peso (GP), o consumo de ração (CR), a conversão alimentar (CA), a biomassa corporal acumulada (BCA) e a umidade da cama (UC) aumentaram linearmente com a inclusão de GB. No experimento III, de 15 a 35 dias de idade, foram utilizadas 1.032 codornas, distribuídas sob as mesmas condições do experimento II. O GP, o CR, a BCA, a UC, o peso de peito (PPEI) e o rendimento de peito (RPEI) aumentaram linearmente com a inclusão de GB. Considerando-se os dados de desempenho, a GB pode ser incluída até o nível de 15%...


Three experiments were carried out aiming to determine the nutritive value and verify the performance of meat quails feed with crude glycerin (CG). In the first trial 75 quails were used, allocated in a completely randomized design, consisting in three treatments and five replications. The treatments consisted of one reference diet (RD) and two test diets (TD), in which the CG replaced the RD at levels of eight and 12%. The estimated value of metabolizable energy corrected for nitrogen balance was 4,893kcal/kg. In experiment two o, from d 1 to 14, 1,320 not sexed quails were used, allotted in a completely randomized design, with six treatments and 4 four replications. The treatments consisted of six diets with increased levels of CG (0; 3; 6; 9; 12 and 15%). The live weight (LW), weight gain (WG), feed intake (FI), feed conversion (FC), biomass accumulated body (BAB) and litter moisture (LM) increased linearly with the inclusion of CG. Considering the performance data, it can be concluded that CG can be included in the diets up to15%. In experiment three, d 15 to 35, 1,032 quails were used, allocated under the same conditions of experiment two. The WG, FI, BAB, LM, breast weight (BW) and breast yield (BY) increased linearly with the inclusion of CG. Considering the performance data, it can be concluded that the CG can be included in the diets up to the level of 15%...


Assuntos
Animais , Coturnix/metabolismo , Glicerol/administração & dosagem , Glicerol/análise , Metabolismo , Ração Animal/análise
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