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1.
Braz J Biol ; 83: e277437, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38422256

RESUMO

The use of residues from coffee production to obtain biochar is a sustainable approach, which aims to minimize the environmental impact of these materials. In this study, the effect of adding coffee straw biochar on the physiological quality of lettuce and sorghum seeds was investigated. Thus, the objective of this work was to study the effect of adding different concentrations of coffee biochar in the substrate composition on the physiological quality of lettuce (Lactuca sativa) and sorghum (Sorghum bicolor) seeds. The experimental design used was completely randomized, with five concentrations of biochar (0; 7.5; 15; 30 and 60%), conducted with four replications of 25 seeds. The use of biochar in the concentrations studied does not provide an increase in the average germination percentage and vigor of lettuce and sorghum seeds. The increase in the concentration of biochar caused less seed vigor, suggesting a toxic effect. For seed germination, there was no significant difference between lettuce and sorghum species, regardless of treatment. For the germination speed index, sorghum seeds have higher means, except for the treatment with the addition of 15% coffee straw biochar. Lettuce seeds have higher shoot length averages, except for treatment with 100% commercial substrate. The sorghum seeds have higher mean root length and dry mass than lettuce, regardless of the treatment.


Assuntos
Carvão Vegetal , Germinação , Sorghum , Café , Grão Comestível , Lactuca , Sementes/fisiologia
2.
Carbohydr Polym ; 236: 116036, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32172852

RESUMO

Diclofenac sodium (DS) is an emergent pollutant, and among the methods investigated for its removal, adsorption is the most widely utilized technique. Hydroxyapatite and chitosan are biomaterials often used for adsorption. However, both biomaterials are limited due to their low chemical stability in an acidic medium; furthermore, pure hydroxyapatite interacts poorly with diclofenac. In this work, hydroxyapatite was organofunctionalized with 3-aminopropyltrimethoxysilane and further used to obtain amino hydroxyapatite /chitosan hybrids by crosslinking with glutaraldehyde at pH 3, 4, 5, and 6. X-ray diffraction patterns indicated the preservation of the hydroxyapatite phase under all pH conditions. Based on the control reaction of the amino hydroxyapatite with glutaraldehyde and its further reduction in sodium borohydride, the formation of CN moieties was highlighted as the main interaction mechanism between the aldehyde and amino groups. Therefore, crosslinking with glutaraldehyde was evaluated by infrared, Raman spectroscopy, and 13C NMR techniques; the results suggested contributions of imine formation and hydrogen bonding. The hybrid obtained at pH 3 exhibited an enhanced adsorption capacity of 125 mg g-1 at 15 min. The synergy between amino hydroxyapatite and chitosan crosslinked by glutaraldehyde was demonstrated.

3.
Sci Rep ; 7: 44900, 2017 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-28322257

RESUMO

We demonstrate the presence of chaos in stochastic simulations that are widely used to study biodiversity in nature. The investigation deals with a set of three distinct species that evolve according to the standard rules of mobility, reproduction and predation, with predation following the cyclic rules of the popular rock, paper and scissors game. The study uncovers the possibility to distinguish between time evolutions that start from slightly different initial states, guided by the Hamming distance which heuristically unveils the chaotic behavior. The finding opens up a quantitative approach that relates the correlation length to the average density of maxima of a typical species, and an ensemble of stochastic simulations is implemented to support the procedure. The main result of the work shows how a single and simple experimental realization that counts the density of maxima associated with the chaotic evolution of the species serves to infer its correlation length. We use the result to investigate others distinct complex systems, one dealing with a set of differential equations that can be used to model a diversity of natural and artificial chaotic systems, and another one, focusing on the ocean water level.


Assuntos
Modelos Biológicos , Dinâmica não Linear , Processos Estocásticos , Algoritmos , Evolução Biológica , Simulação por Computador
4.
J Med Screen ; 19(1): 1-7, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22345321

RESUMO

OBJECTIVE: To evaluate the effectiveness of two screening methods (imitanciometry screening and questionnaire) to identify children at risk for conductive hearing loss, comparing this data with complete audiologic evaluation. METHODS: Of 507 children aged between three and six, 111 completed all procedures. The observational methods used were: imitanciometry screening, a questionnaire to identify risk factors for hearing loss and complete audiologic evaluation. Results obtained in the first two instruments were compared with results from complete audiologic evaluation (gold standard). From these comparisons, sensitivity and specificity, accuracy, positive and negative predictive values, and odds ratio were determined for the two screening methods and for the combination of both methods. RESULTS: The two methods applied in series (questionnaire and after imitanciometry screening) showed a greater odds ratio and better correlation between sensitivity and proportion of false-positives (ROC curve). CONCLUSION: Combining the two tests in series improved screening accuracy. This combination was the best tool for identifying children at risk for conductive hearing loss.


Assuntos
Técnicas de Diagnóstico Otológico , Perda Auditiva Condutiva/diagnóstico , Programas de Rastreamento/métodos , Idade de Início , Algoritmos , Criança , Pré-Escolar , Análise Custo-Benefício , Técnicas de Diagnóstico Otológico/economia , Técnicas de Diagnóstico Otológico/instrumentação , Feminino , Perda Auditiva Condutiva/epidemiologia , Humanos , Masculino , Programas de Rastreamento/economia , Prevalência , Projetos de Pesquisa , Inquéritos e Questionários
5.
J Mol Cell Cardiol ; 52(2): 493-501, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22056317

RESUMO

The heart responds to sustained overload by hypertrophic growth in which the myocytes distinctly thicken or elongate on increases in systolic or diastolic stress. Though potentially adaptive, hypertrophy itself may predispose to cardiac dysfunction in pathological settings. The mechanisms underlying the diverse morphology and outcomes of hypertrophy are uncertain. Here we used a focal adhesion kinase (FAK) cardiac-specific transgenic mice model (FAK-Tg) to explore the function of this non-receptor tyrosine kinase on the regulation of myocyte growth. FAK-Tg mice displayed a phenocopy of concentric cardiac hypertrophy, reflecting the relative thickening of the individual myocytes. Moreover, FAK-Tg mice showed structural, functional and molecular features of a compensated hypertrophic growth, and preserved responses to chronic pressure overload. Mechanistically, FAK overexpression resulted in enhanced myocardial FAK activity, which was proven by treatment with a selective FAK inhibitor to be required for the cardiac hypertrophy in this model. Our results indicate that upregulation of FAK does not affect the activity of Src/ERK1/2 pathway, but stimulated signaling by a cascade that encompasses PI3K, AKT, mTOR, S6K and rpS6. Moreover, inhibition of the mTOR complex by rapamycin extinguished the cardiac hypertrophy of the transgenic FAK mice. These findings uncover a unique role for FAK in regulating the signaling mechanisms that governs the selective myocyte growth in width, likely controlling the activity of PI3K/AKT/mTOR pathway, and suggest that FAK activation could be important for the adaptive response to increases in cardiac afterload. This article is part of a Special Issue entitled "Local Signaling in Myocytes".


Assuntos
Cardiomegalia/enzimologia , Proteína-Tirosina Quinases de Adesão Focal/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo , Animais , Cardiomegalia/genética , Cardiomegalia/patologia , Feminino , Proteína-Tirosina Quinases de Adesão Focal/genética , Expressão Gênica , Ordem dos Genes , Vetores Genéticos , Masculino , Camundongos , Camundongos Transgênicos , Miocárdio/metabolismo , Miocárdio/patologia , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Transdução de Sinais/efeitos dos fármacos , Sirolimo/farmacologia , Serina-Treonina Quinases TOR/antagonistas & inibidores
6.
J Nanosci Nanotechnol ; 12(10): 8023-8, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23421173

RESUMO

The incorporation process of gold nanoparticles (Au NPs) into self-assembled films was obtained using the layer-by-layer (LbL) technique where two weak polyelectrolytes, i.e., poly(allylamine hydrochloride) (PAH) as polycation and poly(acrylic acid) (PAA) as polyanion, were sequentially adsorbed. To evaluate this process, the films of PAH and PAA were immersed in gold solutions containing different sizes of Au NPs (6 nm and 10 nm) stabilized with poly(vinyl-pyrrolidone) (PVP) before and after treatment with a 0.1 mol L(-1) solution of hydrochloric acid. The systems were analyzed using a multi-method approach involving UV-Visible spectroscopy (UV-Vis), X-ray diffraction (XRD), atomic force (AFM) and transmission electron microscopy (TEM). The results showed that the self-assembled polyelectrolyte films that were not treated by acid showed greater incorporation and better distribution of Au NPs.

7.
Arq. bras. med. vet. zootec ; 62(3): 738-741, jun. 2010. tab
Artigo em Português | VETINDEX | ID: vti-5868

RESUMO

Estudou-se o efeito da endogamia sobre as características sobrevivência (intervalos de 0-30; 30-60; 60-90 e 90-120 dias) e longevidade do escargot da espécie Helix aspersa em três gerações consecutivas de acasalamentos entre irmãos perfeitos. Os animais foram criados em laboratório com temperatura entre 20 e 25ºC e umidade relativa entre 70 a 90 por cento. O menor percentual de sobrevivência ocorreu no primeiro intervalo, mas, com o aumento da endogamia, observou-se diminuição na sobrevivência nos quatro intervalos testados. A longevidade média foi de 314 e 306 dias para as gerações um e três, respectivamente, não tendo sido observados animais em hibernação. O estudo de simulação para o caráter sobrevivência, em função do coeficiente de endogamia, indicou que se deve iniciar uma criação com, pelo menos, 100 reprodutores não aparentados.(AU)


The effect of inbreeding on longevity and viability (intervals of 0-30, 30-60, 60-90, and 90-120 days of birth) in three consecutive generations of full sibs of escargot Helix aspersa raised under laboratory conditions (20-25ºC temperature; 70-90 percent relative humidity) was studied. Inbreeding effects decreased the viability for all the studied intervals. The longevity means were 314 and 306 days, respectively to the first and third generations. Hibernating animals were not observed. Population size of at least 100 non-related mating escargots replaced after 10 generations to avoid inbreeding effect is recommended.(AU)


Assuntos
Animais , Longevidade , Taxa de Sobrevida , Caracois Helix , Endogamia
8.
Arq. bras. med. vet. zootec ; 62(3): 738-741, June 2010. tab
Artigo em Português | LILACS | ID: lil-554946

RESUMO

Estudou-se o efeito da endogamia sobre as características sobrevivência (intervalos de 0-30; 30-60; 60-90 e 90-120 dias) e longevidade do escargot da espécie Helix aspersa em três gerações consecutivas de acasalamentos entre irmãos perfeitos. Os animais foram criados em laboratório com temperatura entre 20 e 25ºC e umidade relativa entre 70 a 90 por cento. O menor percentual de sobrevivência ocorreu no primeiro intervalo, mas, com o aumento da endogamia, observou-se diminuição na sobrevivência nos quatro intervalos testados. A longevidade média foi de 314 e 306 dias para as gerações um e três, respectivamente, não tendo sido observados animais em hibernação. O estudo de simulação para o caráter sobrevivência, em função do coeficiente de endogamia, indicou que se deve iniciar uma criação com, pelo menos, 100 reprodutores não aparentados.


The effect of inbreeding on longevity and viability (intervals of 0-30, 30-60, 60-90, and 90-120 days of birth) in three consecutive generations of full sibs of escargot Helix aspersa raised under laboratory conditions (20-25ºC temperature; 70-90 percent relative humidity) was studied. Inbreeding effects decreased the viability for all the studied intervals. The longevity means were 314 and 306 days, respectively to the first and third generations. Hibernating animals were not observed. Population size of at least 100 non-related mating escargots replaced after 10 generations to avoid inbreeding effect is recommended.


Assuntos
Animais , Caracois Helix , Longevidade , Taxa de Sobrevida , Endogamia
10.
Neurosci Lett ; 419(3): 253-7, 2007 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-17499921

RESUMO

This work was designed to study the influence of drugs during seizures and status epilepticus (SE) induced by pilocarpine and mortality in adult rats. Glutamate (10 and 20 mg/kg), N-methyl-d-aspartate (NMDA, 5 and 10 mg/kg), ketamine (1.5 and 2.0 mg/kg), gabapentin (200 and 250 mg/kg), phenobarbital (50 and 100 mg/kg) and vigabatrin (250 and 500 mg/kg) were administered intraperitoneally, 30 min prior to pilocarpine (400 mg/kg, i.p.). The animals were observed (24 h) to determine: number of peripheral cholinergic signs, tremors, stereotyped movements, seizures, SE, latency to first seizure and number of deaths after pilocarpine treatment. NMDA and glutamate had pro-convulsive effects in both doses tested. Smaller and higher doses of these drugs no protected and increased pilocarpine-induced seizures and/or mortality. Gabapentin, vigabatrin, phenobarbital and ketamine protected against seizures and increased the latency to first seizure. Thus, these results suggest that caution should be taken in the selection of pharmacotherapy and dosages for patients with seizures and SE because of the possibility of facility the convulsive process toxicity, SE and the mortality of adult animals in this seizures model that is similar temporal lobo epilepsy in humans.


Assuntos
Anticonvulsivantes/farmacologia , Receptores de GABA/efeitos dos fármacos , Receptores de Neurotransmissores/efeitos dos fármacos , Convulsões/fisiopatologia , Estado Epiléptico/fisiopatologia , Aminas/farmacologia , Animais , Ácidos Cicloexanocarboxílicos/farmacologia , Antagonistas de Aminoácidos Excitatórios/farmacologia , Gabapentina , Ácido Glutâmico/farmacologia , Glutamina/metabolismo , Ketamina/farmacologia , Masculino , Agonistas Muscarínicos/toxicidade , N-Metilaspartato/farmacologia , Fenobarbital/farmacologia , Pilocarpina/toxicidade , Ratos , Ratos Wistar , Convulsões/induzido quimicamente , Estado Epiléptico/induzido quimicamente , Vigabatrina/farmacologia , Ácido gama-Aminobutírico/metabolismo , Ácido gama-Aminobutírico/farmacologia
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