859 research outputs found
Change in Localization of Alkaline Phosphatase and Mannosidase II by Colchicine Treatment of Primary Cultures of Fetal Rat Hepatocytes
We examined the changes in localization of alkaline phosphatase (ALP) and mannosidase II (man II), a Golgi marker, after colchicine treatment of primary cultures of fetal rat hepatocytes, using double immunofluorescence staining and confocal laser microscopy. In hepatocytes cultured in basal medium, ALP was localized in the perinuclear cytoplasm, and man II was observed in the Golgi region of the cytoplasm. When hepatocytes were cultured in dexamethasone-supplemented medium, ALP was also localized in the plasma membrane surrounding the bile canaliculus-like structure that was formed between adjacent cells. In hepatocytes cultured in the same medium containing colchicine, the structure of microtubules in the cytoplasm was lost, man II exhibited granular distribution scattering throughout the cytoplasm, and ALP was localized in coarse granular sites of the cytoplasm. However, ALP was not colocalized at the same sites as man II. The present study indicated that colchicine inhibits the dexamethasone-promoted translocation of ALP to the plasma membrane surrounding the bile canaliculus-like structure in primary cultures of fetal rat hepatocytes by disassembling microtubules and discomposing the Golgi complex
Lack of evidence for a role of Epstein–Barr virus in the increase of lung cancer in idiopathic pulmonary fibrosis
AbstractIdiopathic pulmonary fibrosis (IPF) is known as an independent risk factor for lung cancer. Because Epstein–Barr virus (EBV) may be involved in the genesis of IPF as well as certain malignancies, we investigated whether EBV contributes to the increased incidence of lung cancer in IPF. The formalin-fixed and paraffin-embedded lung sections were prepared from 22 lung cancer patients with IPF and 22 lung cancer patients without IPF. All of the IPF patients pathologically showed usual interstitial pneumonia. In situ hybridization for EBV-encoded small non-polyadenylated RNAs failed to show positive signals in the cancer tissues of either IPF or non-IPF patients. This study did not provide evidence for an etiologic role of EBV in the development of lung cancer in IPF
Universality of Bias- and Temperature-induced Dephasing in Ballistic Electronic Interferometers
We performed a transport measurement in a ballistic Aharonov-Bohm ring and a
Fabry-Perot type interferometer. In both cases we found that the interference
signal is reversed at a certain bias voltage and that the visibility decays
exponentially as a function of temperature, being in a strong analogy with
recent reports on the electronic Mach-Zehnder interferometers. By analyzing the
data including those in the previous works, the energy scales that characterize
the dephasing are found to be dominantly dependent on the interferometer size,
implying the presence of a universal behavior in ballistic interferometers in
both linear and non-linear transport regimes.Comment: 4 pages, 4 figures, accepted for publication in PRB rapid com
Daily life stress and the cortisol awakening response : testing the anticipation hypothesis
Acknowledgments We thank Paul Stewart for his contribution to data collection and Dr Matthew Jones for programming the handheld computers. Author Contributions Conceived and designed the experiments: WS DJP. Performed the experiments: DJP. Analyzed the data: WS. Wrote the paper: WS DJP.Peer reviewedPublisher PD
The role of a disulfide bridge in the stability and folding kinetics of Arabidopsis thaliana cytochrome c6A
Cytochrome c 6A is a eukaryotic member of the Class I cytochrome c family possessing a high structural homology with photosynthetic cytochrome c 6 from cyanobacteria, but structurally and functionally distinct through the presence of a disulfide bond and a heme mid-point redox potential of + 71 mV (vs normal hydrogen electrode). The disulfide bond is part of a loop insertion peptide that forms a cap-like structure on top of the core α-helical fold. We have investigated the contribution of the disulfide bond to thermodynamic stability and (un)folding kinetics in cytochrome c 6A from Arabidopsis thaliana by making comparison with a photosynthetic cytochrome c 6 from Phormidium laminosum and through a mutant in which the Cys residues have been replaced with Ser residues (C67/73S). We find that the disulfide bond makes a significant contribution to overall stability in both the ferric and ferrous heme states. Both cytochromes c 6A and c 6 fold rapidly at neutral pH through an on-pathway intermediate. The unfolding rate for the C67/73S variant is significantly increased indicating that the formation of this region occurs late in the folding pathway. We conclude that the disulfide bridge in cytochrome c 6A acts as a conformational restraint in both the folding intermediate and native state of the protein and that it likely serves a structural rather than a previously proposed catalytic role. © 2011 Elsevier B.V. All rights reserved
Quantum Fluctuation Theorems
Recent advances in experimental techniques allow one to measure and control
systems at the level of single molecules and atoms. Here gaining information
about fluctuating thermodynamic quantities is crucial for understanding
nonequilibrium thermodynamic behavior of small systems. To achieve this aim,
stochastic thermodynamics offers a theoretical framework, and nonequilibrium
equalities such as Jarzynski equality and fluctuation theorems provide key
information about the fluctuating thermodynamic quantities. We review the
recent progress in quantum fluctuation theorems, including the studies of
Maxwell's demon which plays a crucial role in connecting thermodynamics with
information.Comment: As a chapter of: F. Binder, L. A. Correa, C. Gogolin, J. Anders, and
G. Adesso (eds.), "Thermodynamics in the quantum regime - Fundamental Aspects
and New Directions", (Springer International Publishing, 2018
The impact of emotional well-being on long-term recovery and survival in physical illness: a meta-analysis
This meta-analysis synthesized studies on emotional well-being as predictor of the prognosis of physical illness, while in addition evaluating the impact of putative moderators, namely constructs of well-being, health-related outcome, year of publication, follow-up time and methodological quality of the included studies. The search in reference lists and electronic databases (Medline and PsycInfo) identified 17 eligible studies examining the impact of general well-being, positive affect and life satisfaction on recovery and survival in physically ill patients. Meta-analytically combining these studies revealed a Likelihood Ratio of 1.14, indicating a small but significant effect. Higher levels of emotional well-being are beneficial for recovery and survival in physically ill patients. The findings show that emotional well-being predicts long-term prognosis of physical illness. This suggests that enhancement of emotional well-being may improve the prognosis of physical illness, which should be investigated by future research
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