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1.
Molecules ; 28(9)2023 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-37175109

RESUMO

Foodborne pathogens can have devastating repercussions and significantly threaten public health. Therefore, it is indeed essential to guarantee the sustainability of our food production. Food preservation and storage using nanocomposites is a promising strategy. Accordingly, the present research's objectives were to identify and isolate a few foodborne pathogens from food products, (ii) synthesize and characterize silver nanoparticles (AgNPs) using wet chemical reduction into the lamellar space layer of montmorillonite (MMT), and (iii) investigate the antibacterial potential of the AgNPs/MMT nanocomposite versus isolated strains of bacteria. Six bacterial species, including Escherichia coli, Salmonella spp., Pseudomonas aeruginosa, Staphylococcus aureus, Listeria monocytogenes, and Bacillus cereus were isolated from some food products (meat, fish, cheese, and vegetables). The Ag/MMT nanocomposite was synthesized and characterized using UV-visible spectroscopy, transmission electron microscopy, particle size analyzer, zeta potential, X-ray diffraction (XRD), and scanning electron microscopy with dispersive energy X-ray (EDX). The antibacterial effectiveness of the AgNPs/MMT nanocomposite further investigated distinct bacterial species using a zone of inhibition assay and microtiter-based methods. Nanoparticles with a narrow dimension range of 12 to 30 nm were identified using TEM analysis. The SEM was employed to view the sizeable flakes of the AgNPs/MMT. At 416 nm, the most excellent UV absorption was measured. Four silver metallic diffraction peaks were found in the XRD pattern during the study, and the EDX spectrum revealed a strong signal attributed to Ag nanocrystals. AgNPs/MMT figured out the powerful antibacterial action. The AgNPs/MMT nanocomposite confirmed outstanding minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) against six isolates of foodborne pathogens, ranging from 15 to 75 µg/mL, respectively. The AgNPs/MMT's antibacterial potential against gram-negative bacteria was noticeably better than gram-positive bacteria. Therefore, the AgNPs/MMT nanocomposite has the potential to be used as a reliable deactivator in food processing and preservation to protect against foodborne pathogenic bacteria. This suggests that the nanocomposite may be effective at inhibiting the growth and proliferation of harmful bacteria in food, which could help to reduce the risk of foodborne illness.


Assuntos
Anti-Infecciosos Locais , Nanopartículas Metálicas , Nanocompostos , Animais , Prata/farmacologia , Prata/química , Bentonita/farmacologia , Bentonita/química , Anti-Infecciosos Locais/farmacologia , Nanopartículas Metálicas/química , Antibacterianos/farmacologia , Antibacterianos/química , Testes de Sensibilidade Microbiana , Bactérias , Nanocompostos/química , Difração de Raios X
2.
Mar Pollut Bull ; 174: 113221, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34915420

RESUMO

The Red Sea is exposed to metals from a large variety of natural and anthropogenic sources. In this study, we analyzed 19 common element concentrations in 14 Red Sea zooplankton samples using inductively coupled plasma-optical emission spectrometry (ICP-OES). The average metal or metalloid concentrations of the Red Sea zooplankton were: Ca > Sr > Fe > Al > Zn > As > Cu > Mn > Cr > Mo > Ni > Pb > Cd. The As, Ca, and Cu concentrations significantly increased with increasing latitude, while Cd concentrations decreased (p < 0.01). Our study indicated that anthropogenic activities (i.e., cement factories and oil refining industries) might be the predominant sources of significantly high Cr (1718 mg/kg), Fe (11,274 mg/kg), Mn (57.3 mg/kg), Mo (286 mg/kg), Ni (226 mg/kg), Pb (332 mg/kg), and Zn (17,046 mg/kg) concentrations that recorded in the Central to North Red Sea zooplankton.


Assuntos
Metais Pesados , Oligoelementos , Animais , Efeitos Antropogênicos , Monitoramento Ambiental , Poluição Ambiental , Oceano Índico , Metais Pesados/análise , Oligoelementos/análise , Zooplâncton
3.
Science ; 371(6529)2021 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-33542110

RESUMO

Oceans have become substantially noisier since the Industrial Revolution. Shipping, resource exploration, and infrastructure development have increased the anthrophony (sounds generated by human activities), whereas the biophony (sounds of biological origin) has been reduced by hunting, fishing, and habitat degradation. Climate change is affecting geophony (abiotic, natural sounds). Existing evidence shows that anthrophony affects marine animals at multiple levels, including their behavior, physiology, and, in extreme cases, survival. This should prompt management actions to deploy existing solutions to reduce noise levels in the ocean, thereby allowing marine animals to reestablish their use of ocean sound as a central ecological trait in a healthy ocean.


Assuntos
Organismos Aquáticos/fisiologia , Audição , Ruído , Animais , Oceanos e Mares
4.
J Vasc Surg ; 27(5): 928-35, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9620146

RESUMO

PURPOSE: We describe our initial experience with the use of perigeniculate vessels as outflow tracts in infrainguinal revascularizations for critical limb ischemia. METHODS: Twenty-two such reconstructions were carried out in 20 patients over a 2-year period. Indications for surgery consisted of tissue loss in 9 patients and rest pain in the other 13 patients. Inflow was obtained from the femoral vessels. A variety of graft materials were used, including saphenous vein (16 patients), polytetrafluoroethylene (2 patients), composite (1 patient), and arterial homografts (3 patients). The perigeniculate vessels used were the medial sural artery to the gastrocnemius (arteria suralis) in 16 patients and the highest genicular artery (arteria genu suprema) in the other 6 patients. These vessels were approached via a medial above-the-knee popliteal-type exposure. RESULTS: There were three postoperative deaths. Mean follow-up for the other 17 patients averaged 12 months (range, 3 to 37 months). Three grafts failed (thrombosis) during follow-up, leading to two above-the-knee amputations. One graft stenosis was treated with percutaneous angioplasty. The average postoperative increase in the ankle-brachial index was 0.20. CONCLUSION: These early results appear promising with a 1-year primary patency rate of 77%, assisted primary patency rate of 85%, and a limb-salvage rate of 90% according to the Kaplan-Meier life-table method. This technique is particularly useful when adequate length saphenous vein is not available, no other outflow vessels are available, or other outflow vessels are very calcified and not safely clamped. The continued study of the long-term effectiveness is warranted.


Assuntos
Arteriopatias Oclusivas/cirurgia , Circulação Colateral/fisiologia , Isquemia/cirurgia , Joelho/irrigação sanguínea , Idoso , Amputação Cirúrgica , Angioplastia com Balão , Artérias/cirurgia , Pressão Sanguínea/fisiologia , Prótese Vascular , Implante de Prótese Vascular , Feminino , Artéria Femoral/cirurgia , Seguimentos , Oclusão de Enxerto Vascular/etiologia , Humanos , Joelho/cirurgia , Tábuas de Vida , Masculino , Músculo Esquelético/irrigação sanguínea , Politetrafluoretileno , Artéria Poplítea/cirurgia , Fluxo Sanguíneo Regional/fisiologia , Veia Safena/transplante , Taxa de Sobrevida , Trombose/etiologia , Grau de Desobstrução Vascular
5.
J Mal Vasc ; 21 Suppl A: 36-40, 1996.
Artigo em Francês | MEDLINE | ID: mdl-8713367

RESUMO

Use of bovine collagen for collagen arterial grafts raises the problem of possible contamination with the agents causing subacute spongiform encephalopathy. The safety of these products is the confirmed by the manufacturers and the risk of contamination is practically zero. A prospective non-randomized study conducted from January 1991 to December 1992 compared non-impregnated arterial stents with collagen arterial stents. Among the parameters studied, only the amount of blood transfused was significantly different. Collagen arterial grafts generated less blood loss.


Assuntos
Prótese Vascular/métodos , Colágeno/efeitos adversos , Doenças Priônicas/transmissão , Animais , Artérias , Bovinos , Ensaios Clínicos como Assunto , Humanos , Estudos Prospectivos , Infecções Relacionadas à Prótese/etiologia , Fatores de Risco , Resultado do Tratamento
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