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1.
Biosensors (Basel) ; 12(2)2022 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-35200330

RESUMO

The differentiation of cultivars is carried out by means of morphological descriptors, in addition to molecular markers. In this work, near-infrared spectroscopy (NIR) and chemometric techniques were used to develop classification models for two different commercial sesame cultivars (Sesamum indicum) and 3 different strains. The diffuse reflectance spectra were recorded in the region of 700 to 2500 nm. Based on the application of chemometric techniques: principal component analysis-PCA, hierarchical cluster analysis-HCA, k-nearest neighbor-KNN and the flexible independent modeling of class analogy-SIMCA, from the infrared spectra in the near region, it was possible to perform the genotyping of two sesame cultivars (BRS Seda and BRS Anahí), and to classify these cultivars with 3 different sesame strains, obtaining 100% accurate results. Due to the good results obtained with the implemented models, the potential of the methods for a possible realization of forensic, fast and non-destructive authentication, in intact sesame seeds was evident.


Assuntos
Sesamum , Espectroscopia de Luz Próxima ao Infravermelho , Quimiometria , Genótipo , Análise de Componente Principal , Espectroscopia de Luz Próxima ao Infravermelho/métodos
2.
Mater Sci Eng C Mater Biol Appl ; 125: 112097, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33965107

RESUMO

We report the synthesis of magnetite nanoparticles (MNP) and their functionalization with glycine (MNPGly), ß-alanine (MNPAla), L-phenylalanine (MNPPhAla), D-(-)-α-phenylglycine (MNPPhGly) amino acids. The functionalized nanoparticles were characterized by Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray diffraction (XRD), electron paramagnetic resonance (EPR), vibrating sample magnetometry (VSM), Mössbauer spectroscopy (MS), magnetic hyperthermia (MH), dynamic light scattering and zeta potential. The functionalized nanoparticles had isoelectric points (IEP) at pH ≃ 4.4, 5.8, 5.9 and 6.8 for samples MNPGly, MNPAla, MNPPhGly and MNPPhAla, respectively, while pure magnetite had an IEP at pH 5.6. In the MH experiments, the samples showed specific absorption rate (SAR) of 64, 71, 74, 81 and 66 W/g for MNP, MNPGly, MNPAla, MNPPhGly, and MNPPhAla, respectively. We used a flow cytometric technique to determine the cellular magnetic nanoparticles plus amino acids content. Magnetic fractionation and characterization of Resovist® magnetic nanoparticles were performed for applications in magnetic particle imaging (MPI). We have also studied the antiproliferative and antiparasitic effects of functionalized MNPs. Overall, the data showed that the functionalized nanoparticles have great potential for using as environmental, antitumor, antiparasitic agents and clinical applications.


Assuntos
Antimaláricos , Nanopartículas de Magnetita , Aminoácidos , Citometria de Fluxo , Humanos , Hipertermia , Espectroscopia de Infravermelho com Transformada de Fourier
3.
Arq. bras. med. vet. zootec. (Online) ; 72(1): 169-176, Jan.-Feb. 2020. graf
Artigo em Português | LILACS, VETINDEX | ID: biblio-1088908

RESUMO

O fipronil é um inseticida de toxicidade seletiva amplamente empregado na agricultura e na medicina veterinária. Porém, há relatos de efeitos neurotóxicos dessa substância, que geram prejuízos para vertebrados. Avaliou-se a atividade locomotora, a coordenação motora e a atividade da enzima acetilcolinesterase cerebral em ratos expostos ao fipronil. Ratos Wistar machos adultos (n=15) receberam fipronil em dose de 30mg/kg, por via oral, durante 15 dias; o grupo controle (n=15) foi tratado com solução fisiológica, por via oral, no mesmo período. No 16° dia de experimentação, os animais foram submetidos aos testes de arena de campo aberto e hole board. No 17° dia, foram anestesiados e eutanasiados, procedendo-se à coleta de órgãos, e posteriormente foi feita a avaliação da AChE cerebral. A exposição ao fipronil não provocou alterações significativas sobre a coordenação motora e a atividade locomotora, porém gerou inibição significativa da atividade da acetilcolinesterase cerebral. Esses achados sugerem que o fipronil pode provocar efeitos neurotóxicos em curto prazo, os quais podem ser exacerbados caso a exposição seja prolongada.(AU)


Fipronil is a selective-toxicity insecticide widely used in agriculture and veterinary medicine. However, there are reports of neurotoxic effects of this substance, causing damages to vertebrates. We evaluated the locomotor activity, motor coordination and the activity of brain acetylcholinesterase in rats exposed to fipronil. Adult male Wistar rats (n= 15) received fipronil at a dose of 30mg/kg orally for 15 days; the Control group (n= 15) was treated with oral solution in the same period. On the 16th day of experimentation, the animals were submitted to the open field arena test and hole-board test. On the 17th day, they were anesthetized and euthanized, and organs were collected, and subsequently brain AChE was evaluated. Exposure to fipronil yielded no significant changes on motor coordination and locomotor activity but caused significant inhibition of brain acetylcholinesterase activity. These findings suggest that fipronil may cause short-term neurotoxic effects, which may be exacerbated if exposure is prolonged.(AU)


Assuntos
Animais , Ratos , Praguicidas/toxicidade , Acetilcolinesterase/análise , Exposição a Praguicidas , Síndromes Neurotóxicas/veterinária , Testes de Estado Mental e Demência , Ratos Wistar
4.
Vet Microbiol ; 188: 12-5, 2016 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-27139024

RESUMO

Aeromonas hydrophila is causing substantial economic losses in world aquaculture. This study determined the tolerance limit (LD50-96h) of A. hydrophila in Arapaima gigas, and also investigated the clinical signs after intradermal inoculation. Arapaima gigas fingerlings were inoculated intraperitoneally with 0 (control), 1.0×10(5), 1.0×10(6), 1.0×10(7), 1.0×10(9) and 1.0×10(10)CFU/mL of A. hydrophila for the determination of LD50-96h, which was 1.8×10(8)CFU/mL. In another trial with intradermal inoculation of 1.8×10(8)CFU/mL A. hydrophila, there was a 91.6% of mortality between 8 and 23h, and several clinical signs were found. As follows: depigmentation in the tegument, lesions in the tail and fins, loss of balance, reduction of respiratory movements, hemorrhagic foci, necrotic hemorrhages in the kidney, liver and swim bladder, splenomegaly, ascites in the abdominal cavity and hyperemia, enlargement of the gall bladder, among other clinical signs observed. The results showed that A. gigas has a relative tolerance to A. hydrophila when compared to other Neotropical fish species.


Assuntos
Aeromonas hydrophila/fisiologia , Doenças dos Peixes/microbiologia , Doenças dos Peixes/patologia , Infecções por Bactérias Gram-Negativas/veterinária , Animais , Peixes , Infecções por Bactérias Gram-Negativas/microbiologia , Infecções por Bactérias Gram-Negativas/patologia , Dose Letal Mediana , Rios , Clima Tropical
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