Respiratory function in cybrid cell lines carrying European mtDNA haplogroups: implications for Leber's hereditary optic neuropathy

AbstractThe possibility that some combinations of mtDNA polymorphisms, previously associated with Leber's hereditary optic neuropathy (LHON), may affect mitochondrial respiratory function was tested in osteosarcoma-derived transmitochondrial cytoplasmic hybrids (cybrids). In this cellular system, in the presence of the same nuclear background, different exogenous mtDNAs are used to repopulate a parental cell line previously devoid of its original mtDNA. No detectable differences in multiple parameters exploring respiratory function were observed when mtDNAs belonging to European haplogroups X, H, T and J were used. Different possible explanations for the previously established association between haplogroup J and LHON 11778/ND4 and 14484/ND6 pathogenic mutations are discussed, including the unconventional proposal that mtDNA haplogroup J may exert a protective rather than detrimental effect

Evidence of genetic damage in grass gobies and mussels from the Venice lagoon.

The presence of genetic damage has been investigated in two native species of the Venice lagoon: the common mussel Mytilus galloprovincialis and the grass goby Zosterisessor ophiocephalus. Two sampling campaigns were performed in summer 1998 and 1999. Aromatic-like DNA adducts were analysed in selected tissues of gobies and mussels by using the 32P-postlabelling assay. In 1999, micronuclei and other nuclear abnormalities were additionally scored on gill cells and haemocytes of individual mussels whereas inorganic (As, Cd, Cr, Hg, Ni, Pb, Sn) as well as organic contaminants (polycyclic aromatic hydrocarbons, polychlorinated biphenyls and other chlorinated compounds) were measured in the total mussel pulp. Compared to the lagoon inlet area, gobies and mussels from the industrial district (Marghera) showed significant DNA adduct levels and increased frequencies of cytogenetic alterations (evidence of genetic damage was absent or inconsistent in other sites). The substantial levels of aromatic and chlorinated contaminants detected in mussels from Marghera also support the exposure of native organisms to genotoxic agents

Benzo(a)pyrene-induced DNA damage in Mytilus galloprovincialis: Measurement of bulky DNA adducts and DNA oxidative damage in terms of 8-oxo-7,8-dihydro-2'-deoxyguanosine formation.

Bulky DNA adducts and 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodGuo) were measured in gill DNA of benzo[a]pyrene (B[a]P)-exposed mussels (50 mg kg(-1) dw day(-1)), respectively by the P-32-post-labelling technique and high performance liquid chromatography coupled to electrochemical detection assay. A time-course study was performed for both biomarkers and their potential use for marine biomonitoring discussed for the sentinel species studied. In gills, B[a]P-related DNA adducts were positively correlated with B[ a] P concentration in whole mussel, and were produced in a time-dependent manner relative to exposure. Comparison of adduct levels recorded in this paper in gills (0.149 +/- 0.079 (standard deviation) to 0.480 +/- 0.139 adduct per 10(8) normal nucleotides) with previous measures carried out in the digestive gland of the same animals (0.010 +/- 0.005 to 0.251 +/- 0.062 adduct per 10(8) normal nucleotides) (Akcha et al. in press) showed higher levels in the former tissue (p 0.05), whereas by the chaotropic method lower 8-oxodGuo levels (0.02 p < 0.05) were measured for both tissue (8.3 +/- 2.0 and 4.8 +/- 1.1 8-oxodGuo per 10(5) dGuo respectively). Contributory factors to the lack of observed increase in gill 8-oxodGuo level by B[ a] P exposure could be due to the selected way of exposure (via the feed supply) for which gills were not the target tissue of exposure and artifactual DNA oxidation during sample processing that could have masked the possible B[a]P oxidative DNA damage

European validation of Real-Time PCR method for detection of Salmonella spp. in pork meat

The classical microbiological method for detection of Salmonella spp. requires more than five days for final confirmation, and consequently there is a need for an alternative methodology for detection of this pathogen particularly in those food categories with a short shelf-life. This study presents an international (at European level) ISO 16140-based validation study of a non-proprietary Real-Time PCR-based method that can generate final results the day following sample analysis. It is based on an ISO compatible enrichment coupled to an easy and inexpensive DNA extraction and a consolidated Real-Time PCR assay. Thirteen laboratories from seven European Countries participated to this trial, and pork meat was selected as food model. The limit of detection observed was down to 10CFU per 25g of sample, showing excellent concordance and accordance values between samples and laboratories (100%). In addition, excellent values were obtained for relative accuracy, specificity and sensitivity (100%) when the results obtained for the Real-Time PCR-based methods were compared to those of the ISO 6579:2002 standard method. The results of this international trial demonstrate that the evaluated Real-Time PCR-based method represents an excellent alternative to the ISO standard. In fact, it shows an equal and solid performance as well as it reduces dramatically the extent of the analytical process, and can be easily implemented routinely by the Competent Authorities and Food Industry laboratories