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61.
Andrea Ulbrich Sophie Helene Hemberger Alexandra Loidl Stephanie Dufek Eleonore Pablik Sugarka Fodor Marion Herle Christoph Aufricht 《Amino acids》2013,45(6):1385-1393
Recent studies suggest that the combination of caffeine-containing drinks together with alcohol might reduce the subjective feelings of alcohol intoxication—the so-called “masking effect”. In this study, we aimed to review the effects of alcohol in combination with caffeine or energy drink with special focus on the “masking effect”. Fifty-two healthy male volunteers were analysed concerning breath alcohol concentration and subjective sensations of intoxication using a 18 item Visual Analogue Scale in a randomised, double-blinded, controlled, four treatments cross-over trial after consumption of (A) placebo, (B) alcohol (vodka 37.5 % at a dose of 46.5 g ethanol), (C) alcohol in combination with caffeine at a dose of 80 mg (equivalent to one 250 ml can of energy drink) and (D) alcohol in combination with energy drink at a dose of 250 ml (one can). Primary variables were headache, weakness, salivation and motor coordination. Out of four primary variables, weakness and motor coordination showed a statistically significant difference between alcohol and non-alcohol group, out of 14 secondary variables, five more variables (dizziness, alterations in sight, alterations in walking, agitation and alterations in speech) also showed significant differences due mainly to contrasts with the non-alcohol group. In none of these end points, could a statistically significant effect be found for the additional ingestion of energy drink or caffeine on the subjective feelings of alcohol intoxication. This within-subjects study does not confirm the presence of a “masking effect” when combining caffeine or energy drink with alcohol. 相似文献
62.
63.
Sophie C. Payne Carole A. Bartlett Donna L. Savigni Alan R. Harvey Sarah A. Dunlop Melinda Fitzgerald 《PloS one》2013,8(6)
Partial injury to the central nervous system (CNS) is exacerbated by additional loss of neurons and glia via toxic events known as secondary degeneration. Using partial transection of the rat optic nerve (ON) as a model, we have previously shown that myelin decompaction persists during secondary degeneration. Failure to repair myelin abnormalities during secondary degeneration may be attributed to insufficient OPC proliferation and/or differentiation to compensate for loss of oligodendrocyte lineage cells (oligodendroglia). Following partial ON transection, we found that sub-populations of oligodendroglia and other olig2+ glia were differentially influenced by injury. A high proportion of NG2+/olig2–, NG2+/olig2+ and CC1−/olig2+ cells proliferated (Ki67+) at 3 days, prior to the onset of death (TUNEL+) at 7 days, suggesting injury-related cues triggered proliferation rather than early loss of oligodendroglia. Despite this, a high proportion (20%) of the NG2+/olig2+ OPCs were TUNEL+ at 3 months, and numbers remained chronically lower, indicating that proliferation of these cells was insufficient to maintain population numbers. There was significant death of NG2+/olig2– and NG2−/olig2+ cells at 7 days, however population densities remained stable, suggesting proliferation was sufficient to sustain cell numbers. Relatively few TUNEL+/CC1+ cells were detected at 7 days, and no change in density indicated that mature CC1+ oligodendrocytes were resistant to secondary degeneration in vivo. Mature CC1+/olig2– oligodendrocyte density increased at 3 days, reflecting early oligogenesis, while the appearance of shortened myelin internodes at 3 months suggested remyelination. Taken together, chronic OPC decreases may contribute to the persistent myelin abnormalities and functional loss seen in ON during secondary degeneration. 相似文献
64.
Kyoko E. Yuki Megan M. Eva Etienne Richer Dudley Chung Marilène Paquet Mathieu Cellier Fran?ois Canonne-Hergaux Sophie Vaulont Silvia M. Vidal Danielle Malo 《PloS one》2013,8(2)
Salmonella, a ubiquitous Gram-negative intracellular bacterium, is a food borne pathogen that infects a broad range of hosts. Infection with Salmonella Typhimurium in mice is a broadly recognized experimental model resembling typhoid fever in humans. Using a N-ethyl-N-nitrosurea (ENU) mutagenesis recessive screen, we report the identification of Ity16 (Immunity to Typhimurium locus 16), a locus responsible for increased susceptibility to infection. The position of Ity16 was refined on chromosome 8 and a nonsense mutation was identified in the ankyrin 1 (Ank1) gene. ANK1 plays an important role in the formation and stabilization of the red cell cytoskeleton. The Ank1Ity16/Ity16 mutation causes severe hemolytic anemia in uninfected mice resulting in splenomegaly, hyperbilirubinemia, jaundice, extramedullary erythropoiesis and iron overload in liver and kidneys. Ank1Ity16/Ity16 mutant mice demonstrated low levels of hepcidin (Hamp) expression and significant increases in the expression of the growth differentiation factor 15 (Gdf15), erythropoietin (Epo) and heme oxygenase 1 (Hmox1) exacerbating extramedullary erythropoiesis, tissue iron deposition and splenomegaly. As the infection progresses in Ank1Ity16/Ity16, the anemia worsens and bacterial load were high in liver and kidneys compared to wild type mice. Heterozygous Ank1+/Ity16 mice were also more susceptible to Salmonella infection although to a lesser extent than Ank1Ity16/Ity16 and they did not inherently present anemia and splenomegaly. During infection, iron accumulated in the kidneys of Ank1+/Ity16 mice where bacterial loads were high compared to littermate controls. The critical role of HAMP in the host response to Salmonella infection was validated by showing increased susceptibility to infection in Hamp-deficient mice and significant survival benefits in Ank1
+/Ity16 heterozygous mice treated with HAMP peptide. This study illustrates that the regulation of Hamp and iron balance are crucial in the host response to Salmonella infection in Ank1 mutants. 相似文献
65.
The Calpain/Calpastatin System Has Opposing Roles in Growth and Metastatic Dissemination of Melanoma
Quentin Raimbourg Jo?lle Perez Sophie Vandermeersch Aurélie Prignon Guillaume Hanouna Jean-Philippe Haymann Laurent Baud Emmanuel Letavernier 《PloS one》2013,8(4)
Conventional calpains are ubiquitous cysteine proteases whose activity is promoted by calcium signaling and specifically limited by calpastatin. Calpain expression has been shown to be increased in human malignant cells, but the contribution of the calpain/calpastatin system in tumorigenesis remains unclear. It may play an important role in tumor cells themselves (cell growth, migration, and a contrario cell death) and/or in tumor niche (tissue infiltration by immune cells, neo-angiogenesis). In this study, we have used a mouse model of melanoma as a tool to gain further understanding of the role of calpains in tumor progression. To determine the respective importance of each target, we overexpressed calpastatin in tumor and/or host in isolation. Our data demonstrate that calpain inhibition in both tumor and host blunts tumor growth, while paradoxically increasing metastatic dissemination to regional lymph nodes. Specifically, calpain inhibition in melanoma cells limits tumor growth in vitro and in vivo but increases dissemination by amplifying cell resistance to apoptosis and accelerating migration process. Meanwhile, calpain inhibition restricted to host cells blunts tumor infiltration by immune cells and angiogenesis required for antitumor immunity, allowing tumor cells to escape tumor niche and disseminate. The development of highly specific calpain inhibitors with potential medical applications in cancer should take into account the opposing roles of the calpain/calpastatin system in initial tumor growth and subsequent metastatic dissemination. 相似文献
66.
Sophie Sanchez Vincent Dupret Paul Tafforeau Katherine M. Trinajstic Bettina Ryll Pierre-Jean Gouttenoire Lovisa Wretman Louise Zylberberg Fran?oise Peyrin Per E. Ahlberg 《PloS one》2013,8(2)
Background
Firm attachments binding muscles to skeleton are crucial mechanical components of the vertebrate body. These attachments (entheses) are complex three-dimensional structures, containing distinctive arrangements of cells and fibre systems embedded in the bone, which can be modified during ontogeny. Until recently it has only been possible to obtain 2D surface and thin section images of entheses, leaving their 3D histology largely unstudied except by extrapolation from 2D data. Entheses are frequently preserved in fossil bones, but sectioning is inappropriate for rare or unique fossil material.Methodology/Principal Findings
Here we present the first non-destructive 3D investigation, by propagation phase contrast synchrotron microtomography (PPC-SRµCT), of enthesis histology in extant and fossil vertebrates. We are able to identify entheses in the humerus of the salamander Desmognathus from the organization of bone-cell lacunae and extrinsic fibres. Statistical analysis of the lacunae differentiates types of attachments, and the orientation of the fibres, reflect the approximate alignment of the muscle. Similar histological structures, including ontogenetically related pattern changes, are perfectly preserved in two 380 million year old fossil vertebrates, the placoderm Compagopiscis croucheri and the sarcopterygian fish Eusthenopteron foordi.Conclusions/Significance
We are able to determine the position of entheses in fossil vertebrates, the approximate orientation of the attached muscles, and aspects of their ontogenetic histories, from PPC-SRµCT data. Sub-micron microtomography thus provides a powerful tool for studying the structure, development, evolution and palaeobiology of muscle attachments. 相似文献67.
68.
Olivier Lambert Mélanie Piroux Sophie Puyo Chantal Thorin Monique L'Hostis Laure Wiest Audrey Buleté Frédéric Delbac Hervé Pouliquen 《PloS one》2013,8(6)
Background
The honey bee, Apis mellifera, is frequently used as a sentinel to monitor environmental pollution. In parallel, general weakening and unprecedented colony losses have been reported in Europe and the USA, and many factors are suspected to play a central role in these problems, including infection by pathogens, nutritional stress and pesticide poisoning. Honey bee, honey and pollen samples collected from eighteen apiaries of western France from four different landscape contexts during four different periods in 2008 and in 2009 were analyzed to evaluate the presence of pesticides and veterinary drug residues.Methodology/Findings
A multi-residue analysis of 80 compounds was performed using a modified QuEChERS method, followed by GC-ToF and LC−MS/MS. The analysis revealed that 95.7%, 72.3% and 58.6% of the honey, honey bee and pollen samples, respectively, were contaminated by at least one compound. The frequency of detection was higher in the honey samples (n = 28) than in the pollen (n = 23) or honey bee (n = 20) samples, but the highest concentrations were found in pollen. Although most compounds were rarely found, some of the contaminants reached high concentrations that might lead to adverse effects on bee health. The three most frequent residues were the widely used fungicide carbendazim and two acaricides, amitraz and coumaphos, that are used by beekeepers to control Varroa destructor. Apiaries in rural-cultivated landscapes were more contaminated than those in other landscape contexts, but the differences were not significant. The contamination of the different matrices was shown to be higher in early spring than in all other periods.Conclusions/Significance
Honey bees, honeys and pollens are appropriate sentinels for monitoring pesticide and veterinary drug environmental pollution. This study revealed the widespread occurrence of multiple residues in beehive matrices and suggests a potential issue with the effects of these residues alone or in combination on honey bee health. 相似文献69.
Human scent identification is based on a matching-to-sample task in which trained dogs are required to compare a scent sample collected from an object found at a crime scene to that of a suspect. Based on dogs’ greater olfactory ability to detect and process odours, this method has been used in forensic investigations to identify the odour of a suspect at a crime scene. The excellent reliability and reproducibility of the method largely depend on rigor in dog training. The present study describes the various steps of training that lead to high sensitivity scores, with dogs matching samples with 90% efficiency when the complexity of the scents presented during the task in the sample is similar to that presented in the in lineups, and specificity reaching a ceiling, with no false alarms in human scent matching-to-sample tasks. This high level of accuracy ensures reliable results in judicial human scent identification tests. Also, our data should convince law enforcement authorities to use these results as official forensic evidence when dogs are trained appropriately. 相似文献
70.
Constance Holman Sophie K. Piper Ulrike Grittner Andreas Antonios Diamantaras Jonathan Kimmelman Bob Siegerink Ulrich Dirnagl 《PLoS biology》2016,14(1)
Given small sample sizes, loss of animals in preclinical experiments can dramatically alter results. However, effects of attrition on distortion of results are unknown. We used a simulation study to analyze the effects of random and biased attrition. As expected, random loss of samples decreased statistical power, but biased removal, including that of outliers, dramatically increased probability of false positive results. Next, we performed a meta-analysis of animal reporting and attrition in stroke and cancer. Most papers did not adequately report attrition, and extrapolating from the results of the simulation data, we suggest that their effect sizes were likely overestimated.
Where have all the rodents gone?Ooh ooh, ooh ooh, oohTo non-random attrition, every oneWhen will they ever learn?—with apologies to Pete Seeger, 1955相似文献