Histological analysis and ancient DNA amplification of human bone remains found in caius iulius polybius house in pompeii.
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Thirteen skeletons found in the Caius Iulius Polybius house, which has been the object of intensive study since its discovery in Pompeii 250 years ago, have provided an opportunity to study either bone diagenesis by histological investigation or ancient DNA by polymerase chain reaction analysis. DNA analysis was done by amplifying both X- and Y-chromosomes amelogenin loci and Y-specific alphoid repeat locus. The von Willebrand factor (vWF) microsatellite locus on chromosome 12 was also analyzed for personal identification in two individuals showing alleles with 10/11 and 12/12 TCTA repeats, respectively. Technical problems were the scarcity of DNA content from osteocytes, DNA molecule fragmentation, microbial contamination which change bone structure, contaminating human DNA which results from mishandling, and frequent presence of Taq DNA polymerase inhibiting molecules like polyphenols and heavy metals. The results suggest that the remains contain endogenous human DNA that can be amplified and analyzed. The amplifiability of DNA corresponds to the bone preservation and dynamics of the burial conditions subsequent to the 79 A.D. eruption. (+info)
Microbial synthesis of coniferyl alcohol by the fungus Byssochlamys fulva V107.
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Coniferyl alcohol (123 mM = 21.9 g/l) was synthesized from eugenol with a yield of 94.6% in a 36 h fed-batch bioconversion using resting cells of the fungus Byssochlamys fulva V107. (+info)
The antioxidant neuroprotective effects of estrogens and phenolic compounds are independent from their estrogenic properties.
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Among the family of steroidal molecules, only estrogens have the capability of preventing neuronal cell death caused by increased oxidative burden. Employing neuronal cell lines, brain membrane, and low density lipoprotein oxidation assays, we show that the antioxidant and neuroprotective effects of estrogens are dependent not on their genomic properties as hormones but rather on their basic chemical properties as hydrophobic phenolic molecules. Concentrations of 17beta-estradiol of 0.1-500 nM, which confer maximum estrogen receptor-dependent gene transcription in vitro as well as maximum estrogen receptor binding, respectively, do not show antioxidant or neuroprotective effects. In contrast, phenolic compounds such as 2,4,6-trimethylphenol, N-acetylserotonin, and 5-hydroxyindole exhibit neuroprotective effects without any estrogenicity. Comparing various natural and synthetic mono- and polyphenolic compounds, no correlation between their antioxidant cytoprotective effect and their estrogenic potency can be seen. These results call into question the idea of a general correlation between the intended pharmacological effects of estrogens and phenolic compounds and their effect on estrogen receptor-dependent pathways. Furthermore, they may open the door toward the rational design of neuroprotective antioxidants with decreased hormonal side effects. (+info)
Effect of verbascoside on decreasing concentration of oxygen free radicals and lipid peroxidation in skeletal muscle.
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AIM: To detect the effects of verbascoside on decreasing the concentration of oxygen free radicals (OFR) and lipid peroxidation in skeletal muscle resulting from exhaustive exercise. METHODS: Electron spin resonance (ESR) technique and thiobarbituric acid reaction (TBAR) method were used to detect the concentration of OFR in intact gastrocnemius muscle and the contents of milondialdehyde (MDA) in muscle homogenate. RESULTS: Verbascoside decreased the concentration of OFR (P < 0.05) and the level of lipid peroxidation (P < 0.05) in muscle caused by exercise. CONCLUSION: Verbascoside has the effects of reducing oxidative stress in muscle caused by exhaustive exercise by decreasing the concentration of free radicals and the level of lipid peroxidation. (+info)
Normal reproductive organ development in CF-1 mice following prenatal exposure to bisphenol A.
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Bisphenol A (BPA) is a monomer used in the manufacture of a multitude of chemical products, including epoxy resins and polycarbonate. The objective of this study was to evaluate the effects of BPA on male sexual development. This study, performed in CF-1 mice, was limited to the measurement of sex-organ weights, daily sperm production (DSP), epididymal sperm count, and testis histopathology in the offspring of female mice exposed to low doses of BPA (0, 0.2, 2, 20, or 200 microg/kg/day), by deposition in the mouth on gestation days 11-17. Male sexual development determinations were made in offspring at 90 days-of-age. Since this study was conducted to investigate and clarify low-dose effects reported by S. C. Nagel et al., 1997, Environ. Health Perspect. 105, 70-76, and F. S. vom Saal et al., 1998, Toxicol. Indust. Health 14, 239-260, our study protocol purposely duplicated the referenced studies for all factors indicated as critical by those investigators. An additional group was dosed orally with 0.2 microg/kg/day of diethylstilbestrol (DES), which was selected based on the maternal dose reported to have maximum effect on the prostate of developing offspring, by F. S. vom Saal (1996, personal communication), vom Saal et al. (1997, Proc. Natl. Acad. Sci. U S A 94, 2056-2061). Tocopherol-stripped corn oil was used as the vehicle for BPA and DES, and was administered alone to control animals. No treatment-related effects on clinical observations, body weight, or food consumption were observed in adult females administered any dose of BPA or DES. Similarly, no treatment-related effects on growth or survival of offspring from dams treated with BPA or DES were observed. The total number of pups born per litter was slightly lower in the 200-microg/kg/day BPA group when compared to controls, but this change was not considered treatment-related since the litter size was within the normal range of historical controls. There were no treatment-related effects of BPA or DES on testes histopathology, daily sperm production, or sperm count, or on prostate, preputial gland, seminal vesicle, or epididymis weights at doses previously reported to affect these organs or at doses an order of magnitude higher or lower. In conclusion, under the conditions of this study, the effects of low doses of BPA reported by S. C. Nagel et al., 1997 (see above) and F. S. vom Saal et al., 1998 (see above), or of DES reported by F. S. vom Saal et al., 1997 (see above) were not observed. The absence of adverse findings in the offspring of dams treated orally with DES challenges the "low-dose hypothesis" of a special susceptibility of mammals exposed perinatally to ultra-low doses of even potent estrogenic chemicals. Based on the data in the present study and the considerable body of literature on effects of BPA at similar and much higher doses, BPA should not be considered as a selective reproductive or developmental toxicant. (+info)
Quinol-glutathione conjugate-induced mutation spectra in the supF gene replicated in human AD293 cells and bacterial MBL50 cells.
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Hydroquinone is a nephrocarcinogen in rats but generally tests negative in standard mutagenicity assays. However, 2,3,5-tris-(glutathion-S-yl)hydroquinone, a potent nephrotoxic metabolite of hydroquinone, and 2-bromo-bis-(glutathion-S-yl)hydroquinone, another cytotoxic quinol-glutathione (GSH) conjugate, cause extensive single strand breaks in DNA in a manner that is dependent on the formation of reactive oxygen species. We, therefore, investigated whether quinol-GSH conjugates have the potential to behave as genotoxicants. The shuttle vector pSP189, containing the supF gene, was treated with 2,3,5-tris-(glutathion-S-yl)hydroquinone and replicated in both human AD293 cells and Escherichia coli MBL50 cells. The mutation frequency increased 4.6- and 2.6-fold in human AD293 and bacterial MBL50 cells, respectively. Base substitutions were the major type of mutations, and they occurred predominantly at G:C sites in both cell types. A high frequency of deletions (30%), including < 10- and > 10-bp deletions, were observed in AD293-replicated plasmids. The most common types of mutations in AD293 cells were G:C to A:T transitions (33.8%) and G:C to T:A (29.4%) and G:C to C:G (19.1%) transversions. In MBL50 cells, the major mutations were G:C to T:A (33.8%) and G:C to C:G (31.3%) transversions and G:C to A:T transitions (27.5%). The mutation spectra were similar to those reported for *OH-induced mutations, suggesting that *OH generated from polyphenolic-GSH conjugates not only plays a role in cytotoxicity but also provides a basis for their mutagenicity and carcinogenicity. (+info)
The 102-kilobase pgm locus of Yersinia pestis: sequence analysis and comparison of selected regions among different Yersinia pestis and Yersinia pseudotuberculosis strains.
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We report the complete 119,443-bp sequence of the pgm locus from Yersinia pestis and its flanking regions. Sequence analysis confirms that the 102-kb unstable pgm locus is composed of two distinct parts: the pigmentation segment and a high-pathogenicity island (HPI) which carries virulence genes involved in iron acquisition (yersiniabactin biosynthetic gene cluster). Within the HPI, three genes coding for proteins related to phage proteins were uncovered. They are located at both extremities indicating that the entire HPI was acquired en bloc by phage-mediated horizontal transfer. We identified, within the pigmentation segment, two novel loci that may be involved in virulence: a fimbriae gene cluster and a locus probably encoding a two component regulatory system similar to the BvgAS regulatory system of Bordetella pertussis. Three genes containing frameshift mutations and two genes interrupted by insertion element insertion were found within this region. To investigate diversity among different Y. pestis and Yersinia pseudotuberculosis strains, the sequence of selected regions of the pgm locus and flanking regions were compared from 20 different Y. pestis and 10 Y. pseudotuberculosis strains. The results showed that the genes interrupted in Y. pestis are intact in Y. pseudotuberculosis. However, one of these mutations, in the bvgS homologue, is only present in Y. pestis strains of biovar Orientalis and not in those of the biovars Antiqua and Medievalis. The results obtained by analysis of variable positions in the sequence are in accordance with historical records, confirming that biovar Orientalis is the most recent lineage. Furthermore, sequence comparisons among 29 Yersinia strains suggest that Y. pestis is a recently emerged pathogen that is probably entering the initial phase of reductive evolution. (+info)
Serotonin-2 receptors and human sleep: effect of a selective antagonist on EEG power spectra.
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To investigate the effect on the sleep EEG, a 1-mg oral dose of SR 46349B, a novel 5-HT2 antagonist, was administered three hours before bedtime. The drug enhanced slow wave sleep (SWS) and reduced stage 2 without affecting subjective sleep quality. In nonREM sleep (NREMS) EEG slow-wave activity (SWA; power within 0.75-4.5 Hz) was increased and spindle frequency activity (SFA; power within 12.25-15 Hz) was decreased. The relative NREMS power spectrum showed a bimodal pattern with the main peak at 1.5 Hz and a secondary peak at 6 Hz. A regional analysis based on bipolar derivations along the antero-posterior axis revealed significant 'treatment' x 'derivation' interactions within the 9-16 Hz range. In enhancing SWA and attenuating SFA, the 5-HT2 receptor antagonist mimicked the effect of sleep deprivation, whereas the pattern of the NREMS spectrum differed. (+info)