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901.
Sanchez-Roman I Gomez A Gomez J Suarez H Sanchez C Naudi A Ayala V Portero-Otin M Lopez-Torres M Pamplona R Barja G 《Journal of bioenergetics and biomembranes》2011,43(6):699-708
Methionine dietary restriction (MetR), like dietary restriction (DR), increases rodent maximum longevity. However, the mechanism responsible for the retardation of aging with MetR is still not entirely known. As DR decreases oxidative damage and mitochondrial free radical production, it is plausible to hypothesize that a decrease in oxidative stress is the mechanism for longevity extension with MetR. In the present investigation male Wistar rats were subjected to isocaloric 40% MetR during 7 weeks. It was found that 40% MetR decreases heart mitochondrial ROS production at complex I during forward electron flow, lowers oxidative damage to mitochondrial DNA and proteins, and decreases the degree of methylation of genomic DNA. No significant changes occurred for mitochondrial oxygen consumption, the amounts of the four respiratory complexes (I to IV), and the mitochondrial protein apoptosis-inducing factor (AIF). These results indicate that methionine can be the dietary factor responsible for the decrease in mitochondrial ROS generation and oxidative stress, and likely for part of the increase in longevity, that takes place during DR. They also highlight some of the mechanisms involved in the generation of these beneficial effects. 相似文献
902.
The majority of environmental diseases are multifactorial airway illnesses, including genetic background and exposure to different kind of airborne irritants and allergens. Altered lifestyle and changes in environmental exposures contribute to the occurring of these diseases. The term of environmental illnesses includes the disease primarily caused by pollution of air and water, chemical and physical agents, radiation, contaminated food and direct contact with the toxins we are exposed to natural and/or working environment. The members of the matrix metalloproteinase (MMP) family are involved in the pathogenesis of COPD. MMPs comprise a large family of structurally related zinc metalloendopeptidases with different substrate specificities and possibilities to degrade protein constituents of the extracellular matrix. We investigated immunological status and level of MMP-9 in workers occupationally exposed to volatile aromatic hydrocarbons compared to urban residents and rural areas. The phenotypic profiles of peripheral blood lymphocytes were done by flow cytometry. The method of enzyme immunoassay (ELISA) was used to determine enzyme expression of matrix metalloproteinase-9 (MMP-9). The occupationally exposed group had a significantly elevated level of enzyme MMP-9 in the urine, accompanied with augmentation of cells of innate immunity in peripheral blood, which could contribute to the monitoring, early detection of environmental diseases and consequent earlier and more effective treatment. 相似文献
903.
Wei J Wang W Chopra I Li HF Dougherty CJ Adi J Adi N Wang H Webster KA 《The Journal of biological chemistry》2011,286(16):13995-14006
Brief periods of ischemia do not damage the heart and can actually protect against reperfusion injury caused by extended ischemia. It is not known what causes the transition from protection to irreversible damage as ischemia progresses. c-Jun N-terminal kinase-1 (JNK-1) is a stress-regulated kinase that is activated by reactive oxygen and thought to promote injury during severe acute myocardial infarction. Because some reports suggest that JNK-1 can also be protective, we hypothesized that the function of JNK-1 depends on the metabolic state of the heart at the time of reperfusion, a condition that changes progressively with duration of ischemia. Mice treated with JNK-1 inhibitors or transgenic mice wherein the JNK-1 gene was ablated were subjected to 5 or 20 min of ischemia followed by reperfusion. When JNK-1 was inactive, ischemia of only 5 min duration caused massive apoptosis, infarction, and negative remodeling that was equivalent to or greater than extended ischemia. Conversely, when ischemia was extended JNK-1 inactivation was protective. Mechanisms of the JNK-1 switch in function were investigated in vivo and in cultured cardiac myocytes. In vitro there was a comparable switch in the function of JNK-1 from protective when ATP levels were maintained during hypoxia to injurious when reoxygenation followed glucose and ATP depletion. Both apoptotic and necrotic death pathways were affected and responded reciprocally to JNK-1 inhibitors. JNK-1 differentially regulated Akt phosphorylation of the regulatory sites Ser-473 and Thr-450 and the catalytic Thr-308 site in vivo. The studies define a novel role for JNK-1 as a conditional survival kinase that protects the heart against brief but not protracted ischemia. 相似文献
904.
905.
Keck S Müller I Fejer G Savic I Tchaptchet S Nielsen PJ Galanos C Huber M Freudenberg MA 《Journal of immunology (Baltimore, Md. : 1950)》2011,186(9):5478-5488
In macrophages, two signaling pathways, dependent on MyD88 or TIR domain-containing adaptor-inducing IFN-β (TRIF) signaling, emanate from the LPS receptor TLR4/MD-2. In this study, we show that in murine bone marrow-derived mast cells (BMMCs), only the MyD88-dependent pathway is activated by LPS. The TRIF signaling branch leading both to NF-κB activation and enhanced proinflammatory cytokine production, as well as to IRF3 activation and subsequent IFN-β production, is absent in LPS-stimulated BMMCs. IRF3 activation is also absent in peritoneal mast cells from LPS-injected mice. We observed strongly diminished TRAM expression in BMMCs, but overexpression of TRAM only moderately enhanced IL-6 and did not boost IFN-β responses to LPS in these cells. A combination of very low levels of TRAM and TLR4/MD-2 with the known absence of membrane-bound CD14 are expected to contribute to the defective TRIF signaling in mast cells. We also show that, unlike in macrophages, in BMMCs the TRIF-dependent and -independent IFN-αβ responses to other recognized IFN inducers (dsRNA, adenovirus, and B-DNA) are absent. These results show how the response to the same microbial ligand using the same receptor can be regulated in different cell types of the innate immune system. 相似文献
906.
Vincenza Crupi Graziano Guella Domenico Majolino Ines Mancini Barbara Rossi Rosanna Stancanelli Valentina Venuti Paolo Verrocchio Gabriele Viliani 《Food biophysics》2011,6(2):267-273
The effects of chiral discrimination in inclusion complexes formed by native β-cyclodextrin and its substituted form (namely
methyl-β-cyclodextrin) with racemate or pure enantiomers of the non-steroidal anti-inflammatory drug ibuprofen have been investigated
in water. Stability constants and complexation efficiency have been determined for these host–guest systems with a 1:1 molar
ratio from phase solubility profiles, showing that in aqueous solution, methylated cyclodextrin is a better complex agent
than native cyclodextrin, with more enhanced effects for the (R)-enantiomer. These results have been validated using NMR technique. In particular, 1H NMR spectra in D2O show a splitting of the signals for the methyl group and the aromatic protons close to the asymmetric centre of the racemate
ibuprofen included in cyclodextrin cavity. 相似文献
907.
908.
Anna Medyukhina Nadine Vogler Ines Latka Stefanie Kemper Markus Böhm Benjamin Dietzek Jürgen Popp 《Journal of biophotonics》2011,4(9):627-636
All‐optical microspectroscopic and tomographic tools have a great potential for the clinical investigation of human skin and skin diseases. However, automated optical tomography or even microscopy generate immense data sets. Therefore, in order to implement such diagnostic tools into the medical practice in both hospitals and private practice, there is a need for automated data handling and image analysis ideally implementing automized scores to judge the physiological state of a tissue section. In this contribution, the potential of an image processing algorithm for the automated classification of skin into normal or keloid based on second‐harmonic generation (SHG) microscopic images is demonstrated. Such SHG data is routinely recorded within a multimodal imaging approach. The classification of the tissue implemented in the algorithm employs the geometrical features of collagen patterns that differ depending on the constitution, i.e., physiological status of the skin. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
909.
Fungal laccases have been used in various fields ranging from processes in wood and paper industries to environmental applications. Although a few bacterial laccases have been characterized in recent years, prokaryotes have largely been neglected as a source of novel enzymes, in part due to the lack of knowledge about the diversity and distribution of laccases within Bacteria. In this work genes for laccase-like enzymes were searched for in over 2,200 complete and draft bacterial genomes and four metagenomic datasets, using the custom profile Hidden Markov Models for two- and three-domain laccases. More than 1,200 putative genes for laccase-like enzymes were retrieved from chromosomes and plasmids of diverse bacteria. In 76% of the genes, signal peptides were predicted, indicating that these bacterial laccases may be exported from the cytoplasm, which contrasts with the current belief. Moreover, several examples of putatively horizontally transferred bacterial laccase genes were described. Many metagenomic sequences encoding fragments of laccase-like enzymes could not be phylogenetically assigned, indicating considerable novelty. Laccase-like genes were also found in anaerobic bacteria, autotrophs and alkaliphiles, thus opening new hypotheses regarding their ecological functions. Bacteria identified as carrying laccase genes represent potential sources for future biotechnological applications. 相似文献
910.
Colombo F Baldan F Mazzucchelli S Martin-Padura I Marighetti P Cattaneo A Foglieni B Spreafico M Guerneri S Baccarin M Bertolini F Rossi G Mazzaferro V Cadamuro M Maggioni M Agnelli L Rebulla P Prati D Porretti L 《PloS one》2011,6(6):e21369