RÉSUMÉ
The objective of this study was to examine the association between TNF-α serum levels and -308G>A and -238G>A polymorphisms in the corresponding gene by comparing healthy subjects to colorectal cancer (CRC) patients from a Mexican population. Serum levels of TNF-α were found to significantly differ between CRC patients and controls (P = 0.001), but no relationship between the -308G>A and -238G>A polymorphisms and increased CRC risk was established (P > 0.05). However, an association between the -308G>A variant and disease became evident when the distribution of AA-GA genotypes was examined in patients with hematologic toxicity (neutropenia) and those without (odds ratio = 3.356, 95% confidence interval = 1.295- 8.698, P = 0.013). The GG haplotype was more common in controls than CRC patients, with a frequency of 0.85 among the former, but this difference was not significant (P > 0.05). In conclusion, TNF-α serum levels and AA-AG genotypes of the TNF-α-308G>A polymorphism may significantly contribute to CRC susceptibility in the population examined in this investigation.
Sujet(s)
Tumeurs colorectales/sang , Tumeurs colorectales/génétique , Facteur de nécrose tumorale alpha/sang , Adulte , Études cas-témoins , Femelle , Fréquence d'allèle , Prédisposition génétique à une maladie , Haplotypes , Humains , Mâle , Mexique , Adulte d'âge moyen , Polymorphisme de nucléotide simple , Régions promotrices (génétique) , Facteurs de risque , Facteur de nécrose tumorale alpha/génétiqueRÉSUMÉ
The biodegradation of organic compounds present in water at trace concentration has become a critical environmental problem. In particular, enzymatic oxidation by fungal laccases offers a promising alternative for efficient and sustainable removal of organic pollutants in water. In this work, the biocatalytic ability of laccases from the Pycnoporus sanguineus CS43 fungus was evaluated. A filtered culture supernatant (laccase cocktail) evidenced an enhanced biotransformation capability to remove common endocrine-disruptor compounds (EDCs), such as bisphenol A, 4-nonylphenol, 17-α-ethynylestradiol and triclosan. A biodegradation of around 89-100 % was achieved for all EDCs using synthetic samples (10 mg L-1) and after the enzymatic treatment with 100 U L-1 (50.3 U mg -1). The biodegradation rates obtained were fitted to a first order reaction. Furthermore, enzymatic biocatalytic activity was also evaluated in groundwater samples coming from northwestern Mexico, reaching biotransformation percentages between 55 and 93 % for all tested compounds. As far as we know this is the first study on real groundwater samples in which the enzymatic degradation of target EDCs by a laccase cocktail from any strain of Pycnoporus sanguineus was evaluated. In comparison with purified laccases, the use of cocktail offers operational advantages since additional purification steps can be avoided.