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1.
Photochem Photobiol Sci ; 23(6): 1087-1115, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38763938

RESUMEN

The protection of Earth's stratospheric ozone (O3) is an ongoing process under the auspices of the universally ratified Montreal Protocol and its Amendments and adjustments. A critical part of this process is the assessment of the environmental issues related to changes in O3. The United Nations Environment Programme's Environmental Effects Assessment Panel provides annual scientific evaluations of some of the key issues arising in the recent collective knowledge base. This current update includes a comprehensive assessment of the incidence rates of skin cancer, cataract and other skin and eye diseases observed worldwide; the effects of UV radiation on tropospheric oxidants, and air and water quality; trends in breakdown products of fluorinated chemicals and recent information of their toxicity; and recent technological innovations of building materials for greater resistance to UV radiation. These issues span a wide range of topics, including both harmful and beneficial effects of exposure to UV radiation, and complex interactions with climate change. While the Montreal Protocol has succeeded in preventing large reductions in stratospheric O3, future changes may occur due to a number of natural and anthropogenic factors. Thus, frequent assessments of potential environmental impacts are essential to ensure that policies remain based on the best available scientific knowledge.


Asunto(s)
Ozono Estratosférico , Rayos Ultravioleta , Humanos , Ozono Estratosférico/análisis , Rayos Ultravioleta/efectos adversos , Ozono/química , Cambio Climático
2.
J Agric Food Chem ; 55(22): 9318-24, 2007 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-17924706

RESUMEN

Several cooked meats such as beef (fried, coated-fried), pork (fried, coated-fried), and chicken (fried, griddled, coated-fried, roasted) were analyzed for the heterocyclic amine 2-amino-1-methyl-6-(4-hydroxyphenyl)imidazo[4,5- b]pyridine (4'-OH-PhIP) not commonly determined in food and 2-amino-1-methyl-6-phenylimidazo[4,5- b]pyridine (PhIP). The highest content of 4'-OH-PhIP was found in fried and griddled chicken breast, the concentration being 43.7 and 13.4 ng/g, respectively, whereas the corresponding PhIP concentrations were 19.2 and 5.8 ng/g. The estimated concentration of both pyridines in fried pork loin, in fried pork sausages, and in coated-fried chicken was below 2.5 ng/g. In the rest of the samples, 4'-OH-PhIP was not detected. The analyses were performed by solid-phase extraction and LC-MS/MS. The fragmentation of 4'-OH-PhIP in an ion trap mass analyzer was studied in order to provide information for the identification of 4'-OH-PhIP. Additionally, the effect of red wine marinades on the formation of 4'-OH-PhIP in fried chicken was examined, finding a notable reduction (69%) in the amine's occurrence.


Asunto(s)
Carcinógenos/análisis , Cromatografía Líquida de Alta Presión , Calor , Imidazoles/análisis , Espectrometría de Masas , Carne/análisis , Animales , Bovinos , Pollos , Porcinos , Vino
3.
Food Chem Toxicol ; 45(4): 667-75, 2007 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17141386

RESUMEN

Heterocyclic amines (HAs), which are potent mutagenic and carcinogenic substances, are formed in muscle meats during their cooking under ordinary conditions. In this work, we measured the concentration of 15 HAs in different samples of griddled beef steak, which is one of the most consumed meat items is Spain. Three samples were obtained from different restaurants, and the other sample was cooked under controlled conditions to a well-done degree of doneness. A low-time consuming solid-phase extraction procedure was used to purify the samples, and liquid chromatography-tandem mass spectrometry with an ion trap mass analyzer was used as determination technique. A second well-established purification procedure was used to demonstrate the applicability of the method to the analysis of these kind of samples. 8-MeIQx, 4,8-DiMeIQx, PhIP and the comutagens Harman and Norharman were found in all the samples, at levels ranging from 0.28 to 21.2ngg(-1). AalphaC was found in three samples (0.18-1.41ngg(-1)), whereas Trp-P-1 was detected in two samples (0.35ngg(-1)). MeAalphaC was found in three samples but could only be quantified in one (0.15ngg(-1)). Trp-P-2 and DMIP were also detected in some cases at levels below their limit of quantification. The remaining HAs analyzed were not detected in any of the samples.


Asunto(s)
Aminas/análisis , Culinaria/métodos , Compuestos Heterocíclicos/análisis , Carne/análisis , Mutágenos/análisis , Animales , Bovinos , Imidazoles/análisis , Quinoxalinas/análisis
4.
Acta Orthop Scand ; 69(1): 69-72, 1998 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9524522

RESUMEN

We transferred the trapezius with its bone insertion to the proximal humerus in 6 patients for treatment of a paralytic shoulder secondary to traumatic lesions of the brachial plexus. After 1 year, the shoulder abduction was improved from average 13 degrees (0 degrees-30 degrees) preoperatively to 76 degrees (50 degrees-100 degrees) postoperatively, and the shoulder flexion from 18 degrees (0 degrees-40 degrees) to 78 degrees (45 degrees-110 degrees) postoperatively. All the patients were satisfied with the outcome. We consider that transfer of the trapezius in a paralytic shoulder after brachial plexus injury gives a better outcome than shoulder fusion.


Asunto(s)
Plexo Braquial/lesiones , Músculo Esquelético/trasplante , Parálisis/cirugía , Hombro/inervación , Transferencia Tendinosa/métodos , Adulto , Estudios de Seguimiento , Humanos , Masculino , Músculo Esquelético/inervación , Cuidados Paliativos , Rango del Movimiento Articular , Articulación del Hombro/fisiología
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