A Novel Tool for Specific Detection and Quantification of Chicken/Turkey Parvoviruses To Trace Poultry Fecal Contamination in the Environment

Poultry farming may introduce pathogens into the environment and food chains. High concentrations of chicken/turkey parvoviruses were detected in chicken stools and slaughterhouse and downstream urban wastewaters by applying new PCR-based specific detection and quantification techniques. Our results confirm that chicken/turkey parvoviruses may be useful viral indicators of poultry fecal contamination.     

Micronuclei in lymphocytes from currently active uranium miners

Micronuclei can be used as markers of past radiation exposure, but only few studies have dealt with uranium miners. In this paper, we report on micronuclei in lymphocytes from individuals currently working at Ro?ná, Czech Republic, the last functioning uranium mine in the European Union. A modified micronucleus-centromere test was applied to assess the occurrence of micronuclei in stimulated lymphocytes, as well as their content in terms of whole chromosomes or fragments. Compared with unexposed individuals, the miners had higher frequencies of micronucleus-containing lymphocytes and higher percentages of micronuclei without centromeres, and the differences were significant for both parameters (0.74 ± 0.60 vs. 0.50 ± 0.42, p = 0.017 and 49 ± 44 vs. 12 ± 21, p = 0.0002; means ± standard deviations). There were also significant correlations between one or other of these parameters on the one hand and various dose values on the other, in particular with a 'retrievable' dose, that is, a dose whose effect should still be recognisable in lymphocytes assuming a half-life of 3 years. The 'retrievable' dose at which a doubling of the micronucleus frequency was observed was around 35 mSv, corresponding to a total dose of 90 mSv received while working in the mines. Altogether, our data show that the micronucleus-centromere test is a valuable tool for the assessment of past radiation exposure in uranium miners. The scatter in the data is of course far too great to allow individual dosimetry, but for groups of a few dozen exposed individuals, the method can be used to monitor doses clearly below 100 mSv.     

Critical study of preanalytical and analytical phases of adenine and pyridine nucleotide assay in human whole blood

Intracellular redox and energetic status play a crucial role in cardiovascular diseases and metabolic disorders. The physiological status of reducing agents, such as NADPH and NADH, and of high-energy molecules, such as ATP, is required for antioxidant system activity. For these reasons, an accurate measurement of adenine and pyridine nucleotides is fundamental. In this study we examined the preanalytical phase of reduced pyridine (RPN) and adenine and oxidized pyridine (AOPN) nucleotide assay in human whole blood. Different experimental conditions were applied to RPN alkaline and AOPN acid extracts to find the best analytical performance. Our results show that a good RPN and AOPN linearity (r from 0.994 to 0.999), recovery (near to 100%), and precision (coefficient of variation < 5%) were obtained when supernatant from acid and ultrafiltrate from alkaline extracts were neutralized, frozen, and thawed just before HPLC injection. Since NADH decays rapidly at -80 degrees C, RPN levels must be assayed within 72 h while AOPN can be stored for 1 month at the same temperature. An accurate and quantitative method for nucleotide determination can be obtained by applying the preanalytical conditions proposed in this study.     

Patterns of natural killer cell function activation in response to interferon in chronic HBsAG positive hepatitis: relationship with the state of viral infection and with the early clinical response

In an effort to define immunobiological parameters identifying "responders" vs "non-responders" to IFN among hepatitis patients, 16 patients with chronic active hepatitis were screened for changes of Natural Killer cell activity (NK). 10/16 patients replicated the hepatitis B virus (HBV-DNA positive) whereas 6/16 replicated the defective B virus associated delta virus (HDV-RNA positive). Patients received 9 MU/3x/weekly/3 months of recombinant IFN alpha A. Mean NK activity of the HBV-DNA patients rose significantly from 29.9 +/- 5.3 to 45 +/- 4.7 during therapy, whereas the 6/16 HDV-RNA positive patients did not show any significant increase of NK activity. Interestingly, individual HDV-RNA positive patients exhibiting boosted NK activity also showed improvement of disease confirmed by clearance of intrahepatic delta antigen at one year. No such a correlation was found amongst the HBV-DNA positive patients. These data indicate that in spite of widespread individual variability, IFN-mediated NK boost may herald delta clearance and help in identifying "responders" and "non-responders" in IFN trials.     

Reinfusion of UV-irradiated blood in the treatment of infection. I. Experimental infection with staphylococci

During the last 10 years, reinfusion of UV-irradiated blood has been rediscovered again as a therapeutic method suitable in the treatment of a variety of diseases. The described series of model experiments on rabbits confirm its beneficial effects in the treatment of staphylococcal infection: the control animals reinfused blood not exposed to UV radiation died all within 48 hours after injected with a suspension of live Staphylococcus aureus culture; all rabbits reinfused UV-irradiated blood (2 ml per kg body weight) survived the whole period of observation (30 days); reinfusion of UV-irradiated blood in a volume reduced to 1 ml.kg-1 body weight prolonged the animals' life-span to 96 or 120 hours.     

Age and fertility: can women wait until their early thirties to try for a first birth?

Postponing the start of childbearing raises the question of fertility postponed versus fertility foregone. One of the limitations of previous studies of 'How late can you wait?' is that any observed decline in the probability of conception with age could be due to a decline in fecundability with age or due to a decline in coital frequency with age or due to both factors. Using data from a multinational longitudinal study conducted to determine the daily probability of conception among healthy subjects, a discrete-time event history model with long-term survivors (sterile population) is used to study the relationship between age and fecundability for childless women, while controlling for the pattern of intercourse within a menstrual cycle. The findings suggest that women can wait until their early thirties to try for a first birth, providing that they are not already sterile, as the magnitude of the decline in fecundability is very modest and of little practical importance.     

Coupling of Rigor Mortis and Intestinal Necrosis during C. elegans Organismal Death

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Palmitoylation is a post-translational modification of Alix regulating the membrane organization of exosome-like small extracellular vesicles

Background

Virtually all cell types have the capacity to secrete nanometer-sized extracellular vesicles, which have emerged in recent years as potent signal transducers and cell-cell communicators. The multifunctional protein Alix is a bona fide exosomal regulator and skeletal muscle cells can release Alix-positive nano-sized extracellular vesicles, offering a new paradigm for understanding how myofibers communicate within skeletal muscle and with other organs. S-palmitoylation is a reversible lipid post-translational modification, involved in different biological processes, such as the trafficking of membrane proteins, achievement of stable protein conformations, and stabilization of protein interactions.