1. Genotoxic effects of N-nitrosodicyclohexylamine in isolated human lymphocytes
G A Westphal, M M Müller, C Herting, J Bünger, E Hallier Arch Toxicol. 2001 Apr;75(2):118-22. doi: 10.1007/s002040000205.
Dicyclohexylamine x nitrite is classified as an "experimental equivocal tumorigenic agent" by the National Toxicology Program. Since no genotoxic effects of the substance itself are known, the reported tumorigenic potential of dicyclohexylamine x nitrite could be due to generation of N-nitrosodicyclohexylamine (N-NO-DCHA), which occurs under conditions of use and can be detected in foils that contain dicyclohexylamine x nitrite. Therefore, we investigated possible mutagenic properties of N-NO-DCHA in the Ames test and the cytokinesis-block micronucleus assay with human lymphocytes. Since N-NO-DCHA is not commercially available, the substance was synthesized and purified by thin-layer chromatography. Identity was confirmed by gas chromatography/mass spectroscopy (GC/MS) and 1H- and 13C-NMR. More than 97% purity was achieved. Stability and availability in the solvent were checked by GC/MS. N-NO-DCHA induced micronuclei in isolated human lymphocytes at a dose range of 15-100 micrograms/ml (= 71.4-476.2 microM), exceeding the base rate significantly at one or two nontoxic concentrations in four out of six experiments. For the Ames test, arochlor-1254-, beta-naphthoflavone/phenobarbital- and pyrazole-induced S9-fractions were used with Salmonella typhimurium TA100, TA1535, TA98 and TA104. No effects were seen in the Ames test, with the exception of microcolony induction at doses higher than 250 micrograms (= 1.2 mmol) N-NO-DCHA/plate using TA104 and 20% arochlor-1254 induced S9 at pH 6.5. In conclusion, N-NO-DCHA was negative in the Ames test using TA98, TA100 and TA1535, inconclusive using TA104, and weakly genotoxic in the in vitro micronucleus test with isolated human lymphocytes. With regard to the tumorigenicity of the majority of nitrosamines, our data underline the necessity of further studies on possible genotoxic effects of N-NO-DCHA.
2. Anti-inflammatory mechanisms of bioactive milk proteins in the intestine of newborns
Dereck E W Chatterton, Duc Ninh Nguyen, Stine Brandt Bering, Per Torp Sangild Int J Biochem Cell Biol. 2013 Aug;45(8):1730-47. doi: 10.1016/j.biocel.2013.04.028. Epub 2013 May 6.
The human newborn infant is susceptible to gut inflammatory disorders. In particular, growth-restricted infants or infants born prematurely may develop a severe form of intestinal inflammation known as necrotizing enterocolitis (NEC), which has a high mortality. Milk provides a multitude of proteins with anti-inflammatory properties and in this review we gather together some recent significant advances regarding the isolation and proteomic identification of these minor constituents of both human and bovine milk. We introduce the process of inflammation, with a focus on the immature gut, and describe how a multitude of milk proteins act against the inflammatory process according to both in vitro and in vivo studies. We highlight the effects of milk proteins such as caseins, and of whey proteins such as alpha-lactalbumin, beta-lactoglobulin, lactoferrin, osteopontin, immunoglobulins, trefoil factors, lactoperoxidase, superoxide dismutase, platelet-activating factor acetylhydrolase, alkaline phosphatase, and growth factors (TGF-β, IGF-I and IGF-II, EGF, HB-EGF). The effects of milk fat globule proteins, such as TLR-2, TLR-4, sCD14 and MFG-E8/lactadherin, are also discussed. Finally, we indicate how milk proteins could be useful for the prophylaxis and therapy of intestinal inflammation in infants and children.
3. [Social Aspects of Euthanasia]
Roberto Germán Zurriaráin Cuad Bioet. 2019 Jan-Apr;30(98):23-34.
This article analyzes the issue of euthanasia, but under a concrete point of view, that of its social implications. It is defended here that euthanasia is not exclusively an individual decision, but has, above all, an important social repercussion. If euthanasia were accepted and legalized, the very nature of the medicine and the physician's own identity would undergo a profound transformation. The doctor-patient relationship based on trust would be broken. Also, if euthanasia were endorsed, it would be encouraged that the human being was not valued for his / her being, but for his capacity to produce. Now, vulnerable, fragile and weak people (dependent, old, sick ...) keep their dignity intact, because we have this because of the simple fact of being born as human beings. All human lives are worth living, however sick and deteriorated their bodies are. To admit the opposite is to enter a spiral where the dignity of the human being would become an object of weighting with respect to another value, which, in a hypothetical conflict could be postponed by another. However, Palliative Care takes into account the social dimension of the end of life of the human being. They take care of the sick human being in its entirety. That is why they are the option most in line with the dignity of the human being at the end of his life.