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1.
Parasitol Res ; 119(9): 3109-3112, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32643084

RESUMO

Recent studies have described Spirocerca lupi-like nematodes in the stomach of red foxes (Vulpes vulpes) in Europe. A phylogenetic analysis of those specimens using mitochondrial DNA and their morphological reexamination allowed their characterization as a different species, Spirocerca vulpis. Between the years of 2010 and 2017, roundworms were collected from seven red foxes of northeastern Portugal found at necropsy with nodular lesions on their stomach wall. Histopathological analysis of four foxes revealed granulomatous lesions of the gastric nodules. On morphological assessment, by light microscopy, nematodes revealed the presence of six triangular teeth-like buccal capsule structures, which are absent in S. lupi. Polymerase chain reaction was run to amplify a 551 bp partial fragment of the cytochrome c oxidase subunit 1 gene. Sequences were 99% similar to S. vulpis (85% coverage) of red foxes from Spain and Bosnia and Herzegovina, 99% similar (99% coverage) to sequences of Spirocerca sp. of red foxes from Denmark and 93% similar (99% coverage) to S. lupi from South Africa. This is the first report of S. vulpis in foxes or any other host from Portugal.


Assuntos
Raposas/parasitologia , Infecções por Spirurida/veterinária , Thelazioidea/isolamento & purificação , Animais , Filogenia , Reação em Cadeia da Polimerase , Portugal , Espanha , Infecções por Spirurida/patologia , Estômago/parasitologia , Estômago/patologia , Thelazioidea/classificação , Thelazioidea/genética
2.
Drug Deliv Transl Res ; 12(3): 629-646, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-33860446

RESUMO

Strategies targeting nucleolin have enabled a significant improvement in intracellular bioavailability of their encapsulated payloads. In this respect, assessment of the impact of target cell heterogeneity and nucleolin homology across species (structurally and functionally) is of major importance. This work also aimed at mathematically modelling the nucleolin expression levels at the cell membrane, binding and internalization of pH-sensitive pegylated liposomes encapsulating doxorubicin and functionalized with the nucleolin-binding F3 peptide (PEGASEMP), and resulting cytotoxicity against cancer cells from mouse, rat, canine, and human origin. Herein, it was shown that nucleolin expression levels were not a limitation on the continuous internalization of F3 peptide-targeted liposomes, despite the saturable nature of the binding mechanism. Modeling enabled the prediction of nucleolin-mediated total doxorubicin exposure provided by the experimental settings of the assessment of PEGASEMP's impact on cell death. The former increased proportionally with nucleolin-binding sites, a measure relevant for patient stratification. This pattern of variation was observed for the resulting cell death in nonsaturating conditions, depending on the cancer cell sensitivity to doxorubicin. This approach differs from standard determination of cytotoxic concentrations, which normally report values of incubation doses rather than the actual intracellular bioactive drug exposure. Importantly, in the context of development of nucleolin-based targeted drug delivery, the structural nucleolin homology (higher than 84%) and functional similarity across species presented herein, emphasized the potential to use toxicological data and other metrics from lower species to infer the dose for a first-in-human trial.


Assuntos
Doxorrubicina , Lipossomos , Animais , Linhagem Celular Tumoral , Cães , Doxorrubicina/química , Doxorrubicina/farmacologia , Sistemas de Liberação de Medicamentos , Humanos , Concentração de Íons de Hidrogênio , Lipossomos/química , Camundongos , Peptídeos/química , Fosfoproteínas , Polietilenoglicóis , Proteínas de Ligação a RNA , Ratos , Nucleolina
3.
Animals (Basel) ; 11(11)2021 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-34827761

RESUMO

Wasting disease in small ruminants is frequently detected at slaughterhouses. The wasting disorder is manifested by the deterioration of the nutritional and physiological state of the animal indicated by thinness, emaciation, and cachexia. Evidence of emaciation and cachexia, alone, are pathological conditions leading to carcass condemnation during an inspection. Several diseases are associated with a wasting condition, including scrapie, pseudotuberculosis, tuberculosis, paratuberculosis, Maedi Visna, and tumor diseases. On the other hand, parasitic diseases, nutrition disorders, exposure or ingestion of toxins, metabolic conditions, inadequate nutrition due to poor teeth, or poor alimentary diet are conditions contributing to poor body condition. Classical and atypical scrapie is naturally occurring transmissible spongiform encephalopathies in small ruminants. The etiological agent for each one is prions. However, each of these scrapie types is epidemiologically, pathologically, and biochemically different. Though atypical scrapie occurs at low incidence, it is consistently prevalent in the small ruminant population. Hence, it is advisable to include differential diagnosis of this disease, from other possibilities, as a cause of wasting conditions detected during meat inspection at the abattoir. This manuscript is a review of the measures in force at the abattoir for scrapie control, focusing on the differential diagnosis of gross lesions related to wasting conditions detected in small ruminants during meat inspection.

5.
J Biomater Appl ; 33(3): 380-391, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30223730

RESUMO

This study aims the in vivo biological characterization of an innovative minocycline delivery system, based on polymethylmethacrylate bone cement. Bone cements containing 1% or 2.5% (w/w) minocycline were formulated and evaluated through solid-state characterization. Biological evaluation was conducted in vivo, within a rat model, following the subcutaneous and bone tissue implantation, and tissue implantation associated with Staphylococcus aureus is challenging. The assessment of the tissue/biomaterial interaction was conducted by histologic, histomorphometric and microtomographic techniques. Minocycline addition to the composition of the polymethylmethacrylate bone cement did not modify significantly the cement properties. Drug release profile was marked by an initial burst release followed by a low-dosage sustained release. Following the subcutaneous tissue implantation, a reduced immune-inflammatory reaction was verified, with diminished cell recruitment and a thinner fibro-connective capsule formation. Minocycline-releasing cements were found to enhance the bone-to-implant contact and bone tissue formation, following the tibial implantation. Lastly, an effective antibacterial activity was mediated by the implanted cement following the tissue challenging with S. aureus. Kinetic minocycline release profile, attained with the developed polymethylmethacrylate system, modulated adequately the in vivo biological response, lessening the immune-inflammatory activation and enhancing bone tissue formation. Also, an effective in vivo antibacterial activity was established. These findings highlight the adequacy and putative application of the developed system for orthopedic applications.


Assuntos
Antibacterianos/administração & dosagem , Cimentos Ósseos/química , Implantes de Medicamento/química , Minociclina/administração & dosagem , Polimetil Metacrilato/química , Animais , Antibacterianos/farmacocinética , Antibacterianos/uso terapêutico , Sistemas de Liberação de Medicamentos , Masculino , Minociclina/farmacocinética , Minociclina/uso terapêutico , Ratos Wistar , Infecções Estafilocócicas/tratamento farmacológico , Staphylococcus aureus/efeitos dos fármacos
6.
Lab Anim (NY) ; 41(5): 129-34, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22517091

RESUMO

Oral gavage is a widely used method for administering substances to animals in pharmacological and toxicological studies. The authors evaluated whether oral gavage causes behavioral indicators of stress, increased mortality rate, alterations in food and water consumption and body weight or histological lesions in CD-1 mice. Gavage was carried out once per d for 5 d per week over 6 consecutive weeks. The mortality rate of mice in this study was 15%. Mice subjected to gavage did not undergo changes in food or water consumption during the study, and their mean body weights and relative organ weights were similar to those of mice in the control group. Serum cortisol levels at the time of euthanasia in mice in both groups were within the normal range. Histopathology showed acute esophagitis and pleurisy, indicative of perforation of the esophagus, in the two mice that died but no abnormalities in the other mice. The results suggest that animal stress and mortality related to oral gavage can be minimized when the procedure is carried out by an experienced technician.


Assuntos
Intubação/veterinária , Ciência dos Animais de Laboratório/métodos , Camundongos/fisiologia , Administração Oral , Animais , Peso Corporal , Ingestão de Líquidos , Comportamento Alimentar , Hidrocortisona/sangue , Intubação/efeitos adversos , Masculino , Tamanho do Órgão , Polietilenoglicóis/administração & dosagem , Distribuição Aleatória , Solventes/administração & dosagem , Estresse Fisiológico , Fatores de Tempo
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