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1.
Toxins (Basel) ; 15(3)2023 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-36977059

RESUMO

Aflatoxins (AFs) are fungal metabolites that are found in feed and food. When ruminants eat feed contaminated with aflatoxin B1 (AFB1), it is metabolised and aflatoxin M1 (AFM1) is excreted in the milk. Aflatoxins can result in hepatotoxic, carcinogenic, and immunosuppressive effects. The European Union thus set a low threshold limit (50 ng/L) for presence of AFM1 in milk. This was in view of its possible presence also in dairy products and that quantification of these toxins is mandatory for milk suppliers. In the present study, a total of 95,882 samples of whole raw milk, collected in northern Italy between 2013 and 2021, were evaluated for presence of AFM1 using an ELISA (enzyme-linked immunosorbent assay) method. The study also evaluated the relationship between feed materials collected from the same farms in the same area during the same period (2013-2021) and milk contamination. Only 667 milk samples out of 95,882 samples analysed (0.7%) showed AFM1 values higher than the EU threshold limit of 50 ng/L. A total of 390 samples (0.4%) showed values between 40 and 50 ng/L, thus requiring corrective action despite not surpassing the regulatory threshold. Combining feed contamination and milk contamination data, some feedingstuffs seem to be more effective in defying potential carryover of AFs from feed to milk. Combining the results, it can be concluded that a robust monitoring system that covers both feed, with a special focus on high risk/sentinel matrices, and milk is essential to guarantee high quality and safety standards of dairy products.


Assuntos
Aflatoxina M1 , Aflatoxinas , Animais , Aflatoxina M1/análise , Aflatoxina B1/análise , Leite/química , Ração Animal/análise , Contaminação de Alimentos/análise , Aflatoxinas/análise , Itália
2.
Comput Biol Med ; 127: 104047, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33099220

RESUMO

In this work we address the issue of validating the monodomain equation used in combination with the Bueno-Orovio ionic model for the prediction of the activation times in cardiac electro-physiology of the left ventricle. To this aim, we consider four patients who suffered from Left Bundle Branch Block (LBBB). We use activation maps performed at the septum as input data for the model and maps at the epicardial veins for the validation. In particular, a first set (half) of the latter are used to estimate the conductivities of the patient and a second set (the remaining half) to compute the errors of the numerical simulations. We find an excellent agreement between measures and numerical results. Our validated computational tool could be used to accurately predict activation times at the epicardial veins with a short mapping, i.e. by using only a part (the most proximal) of the standard acquisition points, thus reducing the invasive procedure and exposure to radiation.


Assuntos
Terapia de Ressincronização Cardíaca , Técnicas Eletrofisiológicas Cardíacas , Arritmias Cardíacas , Bloqueio de Ramo , Eletrocardiografia , Ventrículos do Coração , Humanos
3.
Ann Vasc Surg ; 68: 451-459, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32278869

RESUMO

BACKGROUND: Hemodynamics has been known to play a major role in the development of intimal hyperplasia leading to arteriovenous fistula failure. The goal of our study is to investigate the influence of different angles of side-to-end radiocephalic anastomosis on the hemodynamic parameters that promote intimal dysfunction and therefore intimal hyperplasia. METHODS: Realistic three-dimensional meshes were reconstructed using ultrasound measurements from distal side-to-end radiocephalic fistulas. The velocity at the proximal and distal radial inflows and at specific locations along the anastomosis and cephalic vein was measured through duplex ultrasound performed by a single examiner. A computational parametric study, virtually changing the inner angle of anastomosis, was performed. For this purpose, we used advanced computational models that include suitable tools to capture the pulsatile and turbulent nature of the blood flow found in arteriovenous fistulas. The results were analyzed in terms of velocity fields, wall shear stress distribution, and oscillatory shear index. RESULTS: Results show that the regions with high oscillatory shear index, which are more prone to the development of hyperplasia, are greater and progressively shift toward the anastomosis area and the proximal vein segment with the decrease of the inner angle of anastomosis. These results are specific to distal radiocephalic fistulas because they are subject to proximal and distal radial inflow. CONCLUSIONS: The results of this study show that inner anastomosis angles approaching 60-70° seem to yield the best hemodynamic conditions for maturation and long-term patency of distal radiocephalic fistulas. Inner angles greater than 90°, representing the smooth loop technique, did not show a clear hemodynamic advantage.


Assuntos
Derivação Arteriovenosa Cirúrgica , Antebraço/irrigação sanguínea , Hemodinâmica , Modelos Cardiovasculares , Modelagem Computacional Específica para o Paciente , Artéria Radial/cirurgia , Veias/cirurgia , Derivação Arteriovenosa Cirúrgica/efeitos adversos , Velocidade do Fluxo Sanguíneo , Humanos , Hiperplasia , Neointima , Artéria Radial/diagnóstico por imagem , Artéria Radial/fisiopatologia , Estresse Mecânico , Resultado do Tratamento , Ultrassonografia Doppler Dupla , Grau de Desobstrução Vascular , Veias/diagnóstico por imagem , Veias/fisiopatologia
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