409 research outputs found
Options in the biomonitoring approach for assessing exposure and health effects of engineered nanomaterials (ENM): Challenges and perspectives
Biological monitoring (BM) has been used in environmental and occupational toxicology as a
powerful tool to assess both exposure and early effects of xenobiotics, thus allowing the
identification of groups at risk before the manifestation of clinical outcomes. It is thought that
for the ENM with known mechanisms or that share similar injury mechanisms (i.e., oxidative
stress and inflammation, DNA damage) with environmental and occupational ultrafine particles
(UFP), it is theoretically feasible to conduct biomarker studies [1], by assessing the early
biochemical changes indicative of local and systemic oxidative stress, systemic inflammation,
and inflammatory response in target organs.
Already validated biomarkers are now available for BM studies in ENM workers [2, 3].
Abnormalities in exhaled breath condensate (EBC) chemistry reflect intrinsic changes in the
airway lining fluid and lung inflammation; moreover, pilot studies suggest the possibility to
use EBC to assess the target dose (see Peclova D. - present session). Circulating soluble
molecules, antioxidant capacity by the Cu/Zn-superoxide dismutase and glutathione
peroxidase-1, peroxidated lipids and carbonyl groups in serum proteins can help reveal
systemic inflammation; vascular adhesion molecules (e.g., ICAM) can detect endothelial
activation/damage and prothrombotic changes. DNA oxidation products, such as 8-oxo-7,8-
dihydroguanine or the corresponding deoxynucleoside 8-oxo-7,8-dihydro-2´-deoxyguanosine
measured in biological fluids can be regarded as biomarkers of effective dose. The
functional integrity of lung epithelial barrier can be assessed by pneumoproteins. Besides
conventional genotoxicity tests, DNA methylation as well as other epigenetic biomarkers
could reveal new mechanisms of action of NM.
Although inflammation represents the main mechanism of injury for several nanoparticles,
specific physico-chemical properties of ENM can trigger unusual pathophysiological events.
Advances in the system biology and “-omic” techniques should allow to assess whether specific
biological pathways are activated or perturbed by specific ENM, and to identify fingerprints of
selected ENM. Provided that biochemical or functional parameters are supported by consistent
pathophysiological mechanisms, practical considerations suggest to focus now on the sensitivity
instead of the specificity of biomarkers, to assess the association between exposure scenarios
and hazards. To evaluate if quantitative modifications in these biomarkers can reflect relevant
health changes predicting long-term outcomes or simple adaptive phenomena, validation studies
on well characterised groups of exposed workers are needed which also consider the likelihood
of combined exposure, organ specificity and disease specificity, background levels in not
exposed people as well as inter-individual variability in biomarkers pattern [2].
[1] Li, N. and Nel, A.E. 2011. Feasibility of biomarker studies for engineered nanoparticles:
what can be learned from air pollution research. JOEM 53(6): S74–S79
[2] Bergamaschi, E. and Magrini, A. 2012. Biomonitoring. In: Fadeel, B., Pietroiusti, A. and
Shvedova, A. (Eds): Adverse Effects of Engineered Nanomaterials - Exposure, Toxicology,
and Impact on human health. Academic Press - Elsevier, pp. 45-62
[3] Liou, S.H. et al. 2012 Epidemiological study of health hazards among workers handling
engineered nanomaterials. J Nanopart Res 14: 878-9
Towards Reference Values for Malondialdehyde on Exhaled Breath Condensate: A Systematic Literature Review and Meta-Analysis
INSIDE Project: Individual Air Pollution Exposure, Extracellular Vesicles Signaling and Hypertensive Disorder Development in Pregnancy
Proinflammatory Effects of Pyrogenic and Precipitated Amorphous Silica Nanoparticles in Innate Immunity Cells
A harmonized protocol for an international multicenter prospective study of nanotechnology workers: the NanoExplore cohort
Lavoro agile e rischio psicosociale: indagine sulla percezione dei lavoratori su vantaggi e svantaggi dello smart-working correlati allo stress da lavoro ed individuazione di misure correttive.
Occupational exposure to nanomaterials and biomarkers in exhaled air and urine: insights from the NanoExplore international cohort
Recognition and Sensing of Nucleoside Monophosphates by a Dicopper(II) Cryptate
The dicopper complex of a bis-tren cryptand in which the spacer consists of two furane subunits
connected in 2,2' by a -CH2- fragment selectively recognizes guanosine monophosphate with respect
to other nucleoside monophospates (NMPs) in a MeOH/water solution at pH 7. Recognition is efficiently
signaled through the displacement of the indicator 6-carboxyfluorescein bound to the receptor, monitoring
its yellow fluorescent emission. Titration experiments evidenced the occurrence of several simultaneous
equilibria involving 1:1 and 2:1 receptor/NMP and receptor/indicator complexes. It was demonstrated that
the added NMP displaces the indicator from the 2:1 receptor/indicator complex, forming the 1:1 receptor/
analyte inclusion complex. Recognition selectivity is thus ascribed to the nature of nucleotide donor atoms
involved in the coordination and their ability to encompass the CuII-CuII distance within the cryptate
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