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1.
Environ Res ; 251(Pt 1): 118549, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38412915

RESUMO

Antimicrobial Resistance (AMR) poses a global threat to both human health and environmental well-being. Our study delved into Costa Rican wildlife reserves, uncovering a substantial human impact on these ecosystems and underscoring the imperative to pinpoint AMR hotspots. Embracing a One Health perspective, we advocated for a comprehensive landscape analysis that intricately intertwined geographic, climatic, forest, and human factors. This study illuminated the link between laboratory results and observed patterns of antimicrobial use, thereby paving the way for sustainable solutions. Our innovative methodology involved deploying open-ended questions to explore antimicrobial usage across livestock activities, contributing to establishing a comprehensive methodology. Non-invasive sampling in wildlife emerged as a critical aspect, shedding light on areas contaminated by AMR. Feline species, positioned at the apex of the food chain, acted as sentinels for environmental health due to heightened exposure to improperly disposed waste. Regarding laboratory findings, each sample revealed the presence of at least one antimicrobial resistance gene (ARG). Notably, genes encoding resistance to tetracyclines dominated (94.9%), followed by beta-lactams (75.6%), sulfonamides (53.8%), aminoglycosides (51.3%), quinolones (44.9%), phenicols (25.6%), and macrolides (20.5%). Genes encoding polymyxins were not detected. Moreover, 66% of samples carried a multi-resistant microbiome, with 15% exhibiting resistance to three antimicrobial families and 51% to four. The absence of a correlation between forest coverage and ARG presence underscored the profound human impact on wildlife reserves, surpassing previous estimations. This environmental pressure could potentially modify microbiomes and resistomes in unknown ways. As not all antimicrobial families encoding ARGs were utilized by farmers, our next step involved evaluating other human activities to identify the primary sources of contamination. This comprehensive study contributed crucial insights into the intricate dynamics of AMR in natural ecosystems, paving the way for targeted interventions and sustainable coexistence.


Assuntos
Ecossistema , Animais , Costa Rica , Antibacterianos/farmacologia , Gatos , Monitoramento Ambiental/métodos , Farmacorresistência Bacteriana , Humanos
2.
Cancers (Basel) ; 16(1)2023 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-38201433

RESUMO

Neutrophil extracellular traps (NETs) have been implicated in several hallmarks of cancer. Among the protumor effects, NETs promote epithelial-mesenchymal transition (EMT) in different cancer models. EMT has been linked to an enhanced expression of the clotting-initiating protein, tissue factor (TF), thus favoring the metastatic potential. TF may also exert protumor effects by facilitating the activation of protease-activated receptor 2 (PAR2). Herein, we evaluated whether NETs could induce TF expression in breast cancer cells and further promote procoagulant and intracellular signaling effects via the TF/PAR2 axis. T-47D and MCF7 cell lines were treated with isolated NETs, and samples were obtained for real-time PCR, flow cytometry, Western blotting, and plasma coagulation assays. In silico analyses were performed employing RNA-seq data from breast cancer patients deposited in The Cancer Genome Atlas (TCGA) database. A positive correlation was observed between neutrophil/NETs gene signatures and TF gene expression. Neutrophils/NETs gene signatures and PAR2 gene expression also showed a significant positive correlation in the bioinformatics model. In vitro analysis showed that treatment with NETs upregulated TF gene and protein expression in breast cancer cell lines. The inhibition of ERK/JNK reduced the TF gene expression induced by NETs. Remarkably, the pharmacological or genetic inhibition of the TF/PAR2 signaling axis attenuated the NETs-induced expression of several protumor genes. Also, treatment of NETs with a neutrophil elastase inhibitor reduced the expression of metastasis-related genes. Our results suggest that the TF/PAR2 signaling axis contributes to the pro-cancer effects of NETs in human breast cancer cells.

3.
Arq. neuropsiquiatr ; 69(1): 112-117, Feb. 2011. ilus, graf
Artigo em Inglês | LILACS | ID: lil-598356

RESUMO

Several animal experimental models have been used in the study of malignant gliomas. The objective of the study was to test the efficacy of a simple, reproducible and low cost animal model, using human cells of glioblastoma multiforme (GBM) xenotransplantated in subcutaneous tissue of Wistar rats, immunosuppressed with cyclosporin given by orogastric administration, controlled by nonimunosuppressed rats. The animals were sacrificed at weekly intervals and we have observed gradual growth of tumor in the immunosuppressed group. The average tumor volume throughout the experiment was 4.38 cm³ in the immunosuppressed group, and 0.27 cm³ in the control one (p<0.001). Tumors showed histopathological hallmarks of GBM and retained its glial identity verified by GFAP and vimentin immunoreaction. Immunosuppression of rats with cyclosporin was efficient in allowing the development of human glioblastoma cells in subcutaneous tissues. The model has demonstrated the maintenance of most of the histopathological characteristics of human glioblastoma in an heterotopic site and might by considered in research of molecular and proliferative pathways of malignant gliomas.


Vários modelos animais têm sido avaliados no estudo dos gliomas e até o momento nenhum pôde ser considerado ideal. O objetivo deste trabalho é verificar a eficácia de um modelo animal simples, reprodutível e de baixo custo. Utilizamos células humanas de glioblastoma multiforme (GBM) xenotransplantadas em ratos Wistar, submetidos a imunossupressão com ciclosporina administrada por via orogástrica. Células tumorais foram implantadas no tecido subcutâneo dos ratos imunossuprimidos com ciclosporina, sendo o controle feito em ratos não imunossuprimidos. Os animais foram sacrificados em intervalos semanais e foi observado crescimento progressivo do tumor no grupo imunossuprimido. A média do volume tumoral em todo o experimento foi de 4,38 cm³ no grupo imunossuprimido e 0,27 cm³ no grupo controle (p<0,001). Os tumores apresentavam características histopatológica do GBM e mantinham sua identidade glial, verificadas por imunoreação para GFAP e vimentina. A imunossupressão dos ratos com ciclosporina foi eficiente em permitir o desenvolvimento do glioblastoma no tecido subcutâneo. Uma vez que o presente modelo mantém a maioria das características histopatológicas do glioblastoma humano, ele pode ser considerado em estudos que avaliem as vias moleculares e proliferativas dos gliomas malignos.


Assuntos
Animais , Humanos , Masculino , Ratos , Neoplasias Encefálicas/patologia , Ciclosporina/administração & dosagem , Glioblastoma/patologia , Imunossupressores/administração & dosagem , Transplante de Neoplasias/métodos , Administração Oral , Neoplasias Encefálicas/química , Glioblastoma/química , Modelos Animais , Proteínas de Neoplasias/análise , Proteínas do Tecido Nervoso/análise , Ratos Wistar , Carga Tumoral , Transplante Heterólogo/métodos , Vimentina/análise
4.
Rev. cient. (Maracaibo) ; 16(6): 634-641, dic. 2006. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-630989

RESUMO

El objetivo del presente estudio fue evaluar el modelo NRC (1996) nivel I para la predicción de la ganancia diaria de peso en novillas suplementadas bajo condiciones tropicales. Para tal fin, se realizaron dos experimentos. En el experimento 1 se evaluaron 30 novillas divididas en dos grupos de 15 animales cada uno, el grupo suplementado (GS) presentó un peso inicial de 365,27 ± 24,40 kg, recibió concentrado a razón de 1% del peso vivo (5,5% PC, 2,85 Mcal ED) y el no suplementado (GNS) con un peso inicial de 367,47 ± 31,65 kg. En el experimento 2 se utilizaron 45 novillas divididas en dos grupos, el GSb con 22 animales, teniendo un peso inicial de 342,23 ± 36,04 kg se les proporcionó alimento a razón del 1% del peso vivo (13% PC; 3,15 Mcal ED) y el GNSb se constituyó por 23 animales teniendo un peso inicial promedio de 326,30 ± 31,53 kg. En ambos experimentos los animales fueron suplementados a lo largo de 45 días, y estuvieron pastoreando praderas de Estrella Africana (Cynodon nlemfuensis), Candelario (Pennisteum purpureum) y Ratana (Ischaemum indicum). En ambos experimentos no se observaron diferencias (P > 0,05) para los cambios de peso. El GS obtuvo ganancias diarias de peso (GDP) de 0,27 kg/d, mientras que el GNS mostró pérdidas de -0,05 kg/d; en el experimento 2 el GSb presentó GDP de 0,90 kg/d y el GNSb de 0,60 kg/d. La GDP predicha en el experimento 1 fue similar a la ganancia observada para el grupo suplementado (P > 0,05) en contraste con la presentada en el grupo no suplementado en el que la ganancia de peso fue sobrestimada (P < 0,05). En el segundo experimento, la predicción de la GDP tanto para el grupo suplementado como el no suplementado fue subestimada (P < 0,05). El nivel 1 del modelo de simulación NRC no fue apropiado para la predicción de los cambios de peso en novillas bajo condiciones tropicales.


The aim of this study was to evaluate the model NRC level 1 to predict the daily weight gain in heifers supplemented under tropical conditions. For this purpose, two experiments were done, in the first experiment 30 heifers were divided into two groups of fifteen animals each, the supplemented group (GS) showed an initial weight of 365.27 ± 24.40 kg, received commercial concentrate to the ratio of 1% of live weight (5.5% PC 2.85 Mcal ED) and the control group which was not supplemented (GNS) with an initial weight of 367.47 ± 31.65 kg. In the second study 45 heifers were divided in two groups, the GSb with 22 animals having an initial weight of 342.23 ± 36.4 kg and given concentrate to the rate of 1% of live weight (13% PC 3.5 Mcal ED) and the GNSb were made up of 23 animals having an initial average weight of 326.0 ± 31.3 kg. In both trials the animals were supplemented throughout for forty-five days and let them grazed on African Star grass (Cynodon nlemfuensis), Candelario grass (Pennisteum purpureum) and Ratana grass (Ischaemum indicum). In both experiments no differences were observed (P > 0.05) in weight change .The GS had daily weight gains (GDP) of 0.27 kg/d while the GNS showed losses of -0.05 kg/d. In the second trial the GSb showed a GDP of 0.90 kg/d and the GNSb of 0.60 kg/d. The predicted GDP of the first experiment was similar in comparison with the observed value for the supplemented group (P > 0.05), in contrast with that presented in the GNS group in which the daily weight gain was over estimated (P < 0.05). In the second trial the GDP predicted for both groups was under estimated (P < 0.05). The level 1 of the NRC simulation model does not seem to be appropriate for predicting changes in weight in heifers under tropical conditions.

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