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51.
Sleep and Biological Rhythms - The sleep-promoting effect of a hot bath on daytime sleep after night-shift work was assessed by polysomnography. Having an unlimited daytime sleep opportunity,...  相似文献   
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Summary Under experimental conditions of genetic transformation, protamine and total histone were bactericidal for Bacillus subtilis cells. The abilities to cause lethality were very similar for both, either protamine or histone, with no antagonistic effects amongst these natural polycations. With both basic proteins acting simultaneously the enhancement was higher than a summation of the separate lethal effects. Sublethal concentration of protamine added at the beginning of transformation time, produced a strong inhibition of transforming efficiency. The same concentration added later than 10 min from the start of transformation had no inhibitory effect. These facts together with the absence of inhibition by simple pretreatment of DNA alone as well as the cell protection by protamine against lytic activity of lysozyme, suggest a protamine-cell surface interaction which impedes DNA uptake events.  相似文献   
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In the article by E. I. Galanzha et al. (doi: http://dx.doi.org/10.1002/jbio.201300140 ), published in J. Biophotonics 8, 81–93 (2015), the Conflict of Interest statement is missing. This erratum is published to correct this.  相似文献   
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Background

The sensitivity of human Burkitt''s lymphoma cells to rituximab (Rtx) and tositumomab (Tst) was assessed on cells expressing different levels of CD20 on surface. Cells that harbor low CD20 levels may resists against therapeutics response to CD20-specific antibodies. We postulated that, radiation-induced modulation of CD20 surface levels may play a crucial and central role in determining the relative efficacy of rituximab and tositumomab in treating Burkitt''s lymphoma disease. Here, we examined the γ-radiation-induced CD20 expression in the Burkitt lymphoma cell line ‘Daudi’ and the relation of differential levels of CD20 with anti-CD20 mAbs mediated cell death.

Methodology

In this study we examined kinetics of CD20 expression following sub lethal doses ofγ-radiation to Daudi cells and thereafter anti-CD20 mAbs (rituximab and tositumomab) were added in cell suspensions. The correlation of kinetics of CD20 expression and cells treated with anti-CD20 mAbs/or corresponding isotype Abs with special reference to changes in mitochondrial membrane potential and reactive oxygen species generation was also examined. Further, we also investigated the efficacy of anti-CD20 mAbs and possible induction of cell death in relation to levels of CD20 cell surface expression.

Conclusion

This report provides evidence that CD20 expression can be induced by exposure of cells to γ-radiation. In addition, these findings demonstrated that the efficacy of anti-CD20 mAbs is dependent on the surface levels of CD20. Based on these findings, we hypothesized (i) irradiation just prior to immunotherapy may provide new treatment options even in aggressive B cell tumors, which are resistant to current therapies in vivo (ii) The efficacy of induction of apoptosis varies with type of monoclonal antibodies in vitro.  相似文献   
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Our objective was to investigate how sepsis influences cellular dynamics and amyloid formation before and after plaque formation. As such, APP-mice were subjected to a polymicrobial abdominal infection resulting in sepsis at 2 (EarlySepsis) and 4 (LateSepsis) months of age. Behavior was tested before sepsis and at 5 months of age. We could not detect any short-term memory or exploration behavior alterations in APP-mice that were subjected to Early or LateSepsis. Immunohistochemical analysis revealed a lower area of NeuN+ and Iba1+ signal in the cortex of Late compared with EarlySepsis animals (p = 0.016 and p = 0.01), with an increased astrogliosis in LateSepsis animals compared with WT-Sepsis (p = 0.0028), EarlySepsis (p = 0.0032) and the APP-Sham animals (p = 0.048). LateSepsis animals had larger areas of amyloid compared with both EarlySepsis (p = 0.0018) and APP-Sham animals (p = 0.0024). Regardless of the analyzed markers, we were not able to detect any cellular difference at the hippocampal level between groups. We were able to detect an increased inflammatory response around hippocampal plaques in LateSepsis compared with APP-Sham animals (p = 0.0003) and a decrease of AQP4 signal far from Sma+ vessels. We were able to show experimentally that an acute sepsis event before the onset of plaque formation has a minimal effect; however, it could have a major impact after its onset.  相似文献   
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Transgenic Panicum virgatum L. silencing (KD) or overexpressing (OE) specific genes or a small RNA (GAUT4‐KD, miRNA156‐OE, MYB4‐OE, COMT‐KD and FPGS‐KD) was grown in the field and aerial tissue analysed for biofuel production traits. Clones representing independent transgenic lines were established and senesced tissue was sampled after year 1 and 2 growth cycles. Biomass was analysed for wall sugars, recalcitrance to enzymatic digestibility and biofuel production using separate hydrolysis and fermentation. No correlation was found between plant carbohydrate content and biofuel production pointing to overriding structural and compositional elements that influence recalcitrance. Biomass yields were greater for all lines in the second year as plants establish in the field and standard amounts of biomass analysed from each line had more glucan, xylan and less ethanol (g/g basis) in the second‐ versus the first‐year samples, pointing to a broad increase in tissue recalcitrance after regrowth from the perennial root. However, biomass from second‐year growth of transgenics targeted for wall modification, GAUT4‐KD, MYB4‐OE, COMT‐KD and FPGS‐KD, had increased carbohydrate and ethanol yields (up to 12% and 21%, respectively) compared with control samples. The parental plant lines were found to have a significant impact on recalcitrance which can be exploited in future strategies. This summarizes progress towards generating next‐generation bio‐feedstocks with improved properties for microbial and enzymatic deconstruction, while providing a comprehensive quantitative analysis for the bioconversion of multiple plant lines in five transgenic strategies.  相似文献   
60.
Improving the informed consent process in clinical research is of constant concern to regulatory authorities in the field and presents a challenge for both the specialists and patients involved. Informed consent is a process that should adequately match the complexity of clinical research. In analyzing the behaviour of 68 patients during the informed consent process related to the clinical research performed at Neomed Clinical Center in Brasov, we found that many patients do not ask any questions (35.3%). From those who do, part of the questions (20,6%) referred to general aspects (addressed the form but not the gist) of the clinical trial, some (72,8%) referred to specific aspects of the clinical trial they will attend and others (6,6%) unrelated to the clinical trial. These results suggest a lack of interest, awareness, and understanding of the information presented in the informed consent form. The possible underlying causes of this attitude and its bureaucratic, ethic, and legal implications are discussed.  相似文献   
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