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ABSTRACT: There is much concern about the increasing presence in the environment of synthetic chemicals that are able to disrupt the endocrine system. Among these compounds, 4-nonylphenol (4-NP) is one of the most studied xenoestrogens, due to its widespread accumulation in water sediment and consequent presence in fatty acid of aquatic organisms. Here, we have used a zebrafish microarray representing 16,399 genes to study the effects of 4-NP and estradiol-17beta (E2) in adult male zebrafish in order to elucidate the mechanism of action of 4-NP compared with that of E2. The microarray results showed that both 4-NP and E2 induced a strong expression of vitellogenin (VTG), the sex related precursor of the yolk proteins in oviparous vertebrates. Both treatments induced elevated protein turnover upregulating genes involved in proteolysis and those that are constituents of the ribosome. Many genes regulated by 4-NP and E2 are involved in energy metabolism, oxidative stress defense mechanisms, xenobiotic metabolism, and lipid metabolism. A different pattern of expression in the two treatments was found for genes involved in oxidative stress, since E2 seems to induce the mechanism of detoxification, while 4-NP seems to inhibit this protective mechanism of the cell. Overall, these findings demonstrate that the microarray approach can contribute significantly to the understanding of expression patterns induced by E2 and 4-NP in male zebrafish. The results also demonstrate that 4-NP is able to act through an alternative pattern to that of estradiol-17beta, modulating the expression of the same genes in a different manner.
General and Comparative Endocrinology 06/2008; 158(1):138-44. · 3.27 Impact Factor
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ABSTRACT: Identification of genes that are differentially expressed in rats bidirectionally selected for alcohol preference might reveal biological mechanisms underlying alcoholism or related phenotypes. Microarray analysis from medial prefrontal cortex (mPFC), a key brain region for drug reward, indicated increased expression of glutathione-S-transferases of the alpha (Gsta4) and mu (Gstm1-5) classes in ethanol-preferring AA rats compared with nonpreferring ANA rats. Real-time RT polymerase chain reaction (RT-PCR) analysis demonstrated approximately 2-fold higher Gsta4 transcript levels in several brain regions of ethanol-naive AA compared with ANA rats. Differences in mRNA levels were accompanied by differential levels of GSTA4 protein. We identified a novel haplotype variant in the rat Gsta4 gene, defined here as var3. Allele frequencies of var3 were markedly different between AA and ANA rats, 52% and 100%, respectively. Gsta4 expression was strongly correlated with the gene dose of var3, with approximately 60% of the variance in expression accounted for by genotype at this locus. The contribution of glutathione S-transferase expression to the ethanol-preferring phenotype is presently unclear. It could, however, underlie observed differences in life span between AA and ANA lines, prompting a utility of this animal model in aging research.
The FASEB Journal 10/2006; 20(11):1826-35. · 5.71 Impact Factor
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ABSTRACT: The male human body found in an Alpine glacier on September 19, 1991 ("Tyrolean Iceman") has, for the first time in history, given scientists a chance to perform detailed anatomical, histological, and molecular investigations on the organs of a person from the Neolithic Age (5350-5100 B.P.). In the present study, tissue samples aseptically taken from the stomach and the colon of the mummy were utilized for DNA extraction, and the DNA was PCR-amplified, using primer pairs designed to bind to fragments of the 16s ribosomal RNA gene (16s rDNA) of a broad range of bacteria. The PCR products were cloned in plasmid vectors, and the recombinant clones (amplicons) were sequenced. The sequence data were finally used for scanning data libraries containing the corresponding sequences of present-day bacteria, to infer the putative ecophysiology of the ancient ones. The same procedure was repeated on some fragments of grass from the clothing found near the corpse. These fragments were taken as a control of the microbiological situation of the glacier. The results show that the flora of the Iceman's stomach is entirely composed of Burkholderia pickettii, an organism commonly found in aquatic habitats. The colon, on the other hand, contains several members of the fecal flora of humans, such as Clostridium perfringens, C. ghonii, C. sordellii, Eubacterium tenue, and Bacteroides sp. The Iceman's colon, however, was found to contain, rather unexpectedly, also some members of the genus Vibrio. The results are discussed in light of what is known about the preservation of microbial DNA at the Iceman's site and of previous parasitological studies performed on the Iceman himself and on human coprolites.
American Journal of Physical Anthropology 08/2000; 112(3):297-309. · 2.82 Impact Factor
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ABSTRACT: We have isolated DNA from 14 tissue samples from the internal organs of an Andean human mummy (10th-11th century A.D.) and have checked the persistence of the original human and bacterial templates using the following main approaches: 1) amino acid racemization test; 2) quantification of mitochondrial DNA copy number; 3) survey of bacterial DNA in the different organs; 4) sequence analysis of bacterial amplicons of different lengths. The results demonstrate that both the original human DNA and the DNA of the bacteria of the mummy gut are preserved. In particular, sequence analysis of two (respectively 100 and 196 bp in length) libraries of bacterial 16s ribosomal RNA gene amplicons from the mummy colon shows that while the shortest amplicons give only modest and biased indications about the bacterial taxa, the longer amplicons allow the identification several species of the genus Clostridium which are typical of the human colon. This work represents a first example of a methodological approach which is applicable, in principle, to many other natural and artificial mummies and might open the way to the study of the structure of the human microbial ecosystem from prehistory to present.
American Journal of Physical Anthropology 12/1998; 107(3):285-95. · 2.82 Impact Factor
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ABSTRACT: The DNA identification of the microorganisms that colonized the so-called Tyrolean Iceman in the ancient times can offer a
clue to understanding the exact process through which the natural mummification of the 5.100–5.300 year-old body took place.
The results suggest that this process was considerably more complex than previously assumed (wind desiccation followed by
freezing) possibly involving also a prolonged stage of water immersion of the corpse.
Human Evolution 04/1997; 12(3):197-208.
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ABSTRACT: To investigate the origin of the fungal hyphae that cover the grass clothing (cloak, boots) found near the neolithic mummy known as the Tyrolean Iceman, two radiocarbon-dated samples of grass were submitted to DNA extraction. The DNA was then PCR amplified using, respectively, primers specific for the region containing the internal transcribed spacers and the 5.8s rDNA (ITS), and primers specific for an approximately 600-bp long fragment of the nuclear small-subunit ribosomal DNA (SSU rDNA) repeat units of eukaryotes. The amplification products were cloned and sequenced. Sequence analysis of 20 individual ITS clones and of ten SSU rDNA clones indicated that three types of fungal DNA can be extracted from the grass. Phylogenetic analyses, using 5.8s and SSU rDNA fungal reference sequences from EMBL and GenBank databases, suggest that the DNAs come, respectively, from a psychrophilic basidiomycetous yeast, phylogenetically close to Leucosporidium scottii, and from two ascomycetes, one of which is possibly related to the Eurotiales.
Current Genetics 09/1995; 28(3):289-97. · 2.56 Impact Factor
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ABSTRACT: The paper reports on the molecular analysis of samples of approximately 5,300-year-old grass found at the alpine archaeological site where the so-called Tyrolean Iceman was discovered. The grass comes from a cloak made of long grass blades and/or the stuffing of the snow footwear worn by the Iceman. The results show that while the largest fraction of the DNA extractable from the grass is of foreign origin, a much smaller part belongs to the original genetic material of the grass itself, and can be used as a valuable taxonomic clue to the plant species utilized by neolithic men to manufacture their equipment. On the other hand, the foreign DNA, or at least a portion of it, comes from microorganisms-mainly filamentous fungi and unicellular algae-which seem to have been associated with the grass since the time the grass was harvested.
Cellular and Molecular Life Sciences CMLS 05/1994; 50(6):576-584. · 6.57 Impact Factor
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ABSTRACT: Identification of genes that are differentially expressed in rats bidirectionally selected for alcohol preference might reveal biological mechanisms underlying alcoholism or related phenotypes. Microarray analysis from medial prefrontal cortex (mPFC), a key brain region for drug reward, indicated increased expression of glutathione-S-transferases of the alpha (Gsta4) and mu (Gstm1-5) classes in ethanol-preferring AA rats compared with nonpreferring ANA rats. Real-time RT polymerase chain reaction (RT-PCR) analysis demonstrated [~]2-fold higher Gsta4 transcript levels in several brain regions of ethanol-naive AA compared with ANA rats. Differences in mRNA levels were accompanied by differential levels of GSTA4 protein. We identified a novel haplotype variant in the rat Gsta4 gene, defined here as var3. Allele frequencies of var3 were markedly different between AA and ANA rats, 52% and 100%, respectively. Gsta4 expression was strongly correlated with the gene dose of var3, with [~]60% of the variance in expression accounted for by genotype at this locus. The contribution of glutathione S-transferase expression to the ethanol-preferring phenotype is presently unclear. It could, however, underlie observed differences in life span between AA and ANA lines, prompting a utility of this animal model in aging research.--Bjork, K., Saarikoski, S. T., Arlinde, C., Kovanen, L., Osei-Hyiaman, D., Ubaldi, M., Reimers, M., Hyytia, P., Heilig, M. Sommer, W. H. Glutathione-S-transferase expression in the brain: possible role in ethanol preference and longevity
FASEB J. 20(11).
