Milk is an important food in the human diet due to its physico-chemical composition; therefore, it is necessary to monitor contamination by toxic metals such as Pb. Milk sample slurries were prepared using Triton X-100 and nitric acid for direct analysis of Pb using graphite furnace atomic absorption spectrometry - GF AAS. After dilution of the slurries, 10.00µl were directly introduced into the pyrolytic graphite tube without use of a chemical modifier, which acts as an advantage considering this type of matrix. The limits of detection and quantification were 0.64 and 2.14µgl, respectively. The figures of merit studied showed that the proposed methodology without pretreatment of the raw milk sample and using external standard calibration is suitable. The methodology was applied in milk samples from the Guarapuava region, in Paraná State (Brazil) and Pb concentrations ranged from 2.12 to 37.36µgl.
O cachorro-do-mat o (Cerdocyon thous) é encontrado em todo o Brasil. Possui hábito noturno, podendo ser observado nas margens de estradas, onde procura restos de animais atropelados e, por isso, também é vítima frequente de atropelamento. Este estudo visou a caracterização anatômica macro e microscópicas do sistema digestório do cachorro-do-mato. Ele traz subsídios para a realização de procedimentos clínicos e cirúrgicos, além de importantes informações importantes a respeito das estratégias de alimentação, principalmente para indivíduos selvagens que necessitem de cuidados veterinários após resgate em casos de atropelamento, queimadas e enchentes causadas por enchimento de lagos de hidroelétricas ou mesmo em projetos de reprodução em cativeiro e repovoamento. Foram coletadas amostras do sistema digestório de três animais de vida livre da região de Guarapuava-PR. Os cachorros-do-mato estudados tinham comprimento maior do que a média descrita da espécie, possuíam um intestino mais curto e uma relação intestino delgado/comprimento corpóreo menor do que outros carnívoros, além de apresentarem algumas características anatômicas e histológicas diferentes das encontradas na literatura sobre carnívoros.
Usually, the methodologies found in the literature on biological tissue digestion are usually time consuming and use high amounts of reagents. In this study, two methods of preparation of bovine testis samples were evaluated: acid digestion using nitric acid and alkaline solubilization using tetramethylammonium hydroxide. The analytical validation study evaluated the parameters of linearity, limits of detection (acid digestion 0.10; 1.02; 0.16; 0.67 mg kg-1 for Cu, Fe, Mn and Zn, respectively; alkaline solubilization 0.12; 0.74; 0.16; 0.23 mg kg-1 for Cu, Fe, Mn and Zn, respectively) and quantification (acid digestion 0.34; 3.40; 0.53; 2.20 mg kg-1 for Cu, Fe, Mn and Zn, respectively; alkaline solubilization 0.41; 2.50; 0.54; 0.77 mg kg-1 for Cu, Fe, Mn and Zn, respectively), precision (RSD < 7.3% for repeatability and RSD < 15.0% for intermediary precision) and accuracy, being that the percentage of recovery obtained in the acid digestion of 105.50% (Cu), 103.30% (Fe), 94.90% (Mn) and 89.60% (Zn) and in the alkaline solubilization 100.80% (Cu), 98.70% (Fe), 103.70% (Mn) and 95.70% (Zn), therefore, the two procedures were efficient for this type of matrix. The times required for acid digestion and an alkaline solubilization were 1h30min and 1h, respectively.
A insuficiência cardíaca congestiva é uma síndrome clínica caracterizada por disfunção cardíaca com hemodinâmica anormal, liberação de citocinas, ativação neuroendócrina e retenção renal de sódio e água. Diversas etiologias são associadas; porém, a importância da intoxicação por metais pesados na musculatura cardíaca e seu sistema de condução têm sido pouco estudados. Neste estudo, objetivou-se a caracterização histomorfológica do coração de modelos biológicos submetidos à intoxicação aguda por chumbo. Dezoito ratos Wistar foram divididos em três grupos, sendo o chumbo (G1) testado em conjunto com o cobre (G2) e controle. Os animais submetidos à intoxicação experimental por chumbo apresentaram lesões em segmentos miocárdicos em parede livre do ventrículo esquerdo com infiltrado inflamatório mononuclear associado com a degeneração de miofibrilas. Observou-se alteração em gânglios nervosos cardíacos com degeneração neuronal multifocal, localizados principalmente no ventrículo esquerdo e no septo interventricular. Nos demais grupos não se identificaram lesões referentes ao tecido muscular cardíacoe/ou de condução. Concluiu-se que o chumbo possui características de alteração estrutural cardíaca importante, especialmente no que diz respeito aos danos no sistema nervoso cardíaco, devendo-se incluir no rol de possibilidades de eventuais disritmias em animais domésticos.
The objective of the present study was to standardize an immunohistochemical reaction (IHC) for the diagnosis of Newcastle disease virus (NDV) in tissue samples. In order to achieve this aim, pigeons (Columba livia) and chicken (Gallus gallus) were experimentally infected with a pathogenic sample of NDV (São Joao do Meriti strain). The IHC reaction was standardized and tested in samples of lung, liver, spleen and trachea of the experimentally infected birds, and the results showed that from the 20 infected birds, 17 were positive for Newcastle disease antigen immunomarking in the trachea and 11 were positive in the spleen. NDV detection was not achieved in samples of lung and liver, and these tissues are not indicated in NDV detection in the present study.After that, the standardized technique was used in the detection of NDV in samples of trachea and spleen of 46 free-living birds which belonged to 11 different bird orders. The virus was detected in 24 individuals. The order Caprimulgiforme was the only one that did not show any positive animal. These NDV strains circulate in bird populations, generally without causing the disease, in a parasite vs. host balance. Outbreaks may occur when these free-living birds get in contact with commercial birds, with considerable losses to countries that raise and export poultry and poultry products. In conclusion, IHC is a diagnostic tool that may be used in locations that do not have biosafety levels for virus isolation, or that are even not able to perform molecular assays.
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