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991.
Effects of low‐level light therapy on hepatic antioxidant defense in acute and chronic diabetic rats
Jinhwan Lim Zeeshan M. Ali Ruth A. Sanders Ann C. Snyder Janis T. Eells Diane S. Henshel John B. Watkins III 《Journal of biochemical and molecular toxicology》2009,23(1):1-8
Diabetes causes oxidative stress in the liver and other tissues prone to complications. Photobiomodulation by near infrared light (670 nm) has been shown to accelerate diabetic wound healing, improve recovery from oxidative injury in the kidney, and attenuate degeneration in retina and optic nerve. The present study tested the hypothesis that 670 nm photobiomodulation, a low‐level light therapy, would attenuate oxidative stress and enhance the antioxidant protection system in the liver of a model of type I diabetes. Male Wistar rats were made diabetic with streptozotocin (50 mg/kg, ip) then exposed to 670 nm light (9 J/cm2) once per day for 18 days (acute) or 14 weeks (chronic). Livers were harvested, flash frozen, and then assayed for markers of oxidative stress. Light treatment was ineffective as an antioxidant therapy in chronic diabetes, but light treatment for 18 days in acutely diabetic rats resulted in the normalization of hepatic glutathione reductase and superoxide dismutase activities and a significant increase in glutathione peroxidase and glutathione‐S transferase activities. The results of this study suggest that 670 nm photobiomodulation may reduce, at least in part, acute hepatic oxidative stress by enhancing the antioxidant defense system in the diabetic rat model. © 2009 Wiley Periodicals, Inc. J Biochem Mol Toxicol 23:1–8, 2009; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/jbt.20257 相似文献
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Sebiha Cevik Anna A. W. M. Sanders Erwin Van Wijk Karsten Boldt Lara Clarke Jeroen van Reeuwijk Yuji Hori Nicola Horn Lisette Hetterschijt Anita Wdowicz Andrea Mullins Katarzyna Kida Oktay I. Kaplan Sylvia E. C. van Beersum Ka Man Wu Stef J. F. Letteboer Dorus A. Mans Toshiaki Katada Kenji Kontani Marius Ueffing Ronald Roepman Hannie Kremer Oliver E. Blacque 《PLoS genetics》2013,9(12)
Cilia are microtubule-based cell appendages, serving motility, chemo-/mechano-/photo- sensation, and developmental signaling functions. Cilia are comprised of distinct structural and functional subregions including the basal body, transition zone (TZ) and inversin (Inv) compartments, and defects in this organelle are associated with an expanding spectrum of inherited disorders including Bardet-Biedl syndrome (BBS), Meckel-Gruber Syndrome (MKS), Joubert Syndrome (JS) and Nephronophthisis (NPHP). Despite major advances in understanding ciliary trafficking pathways such as intraflagellar transport (IFT), how proteins are transported to subciliary membranes remains poorly understood. Using Caenorhabditis elegans and mammalian cells, we investigated the transport mechanisms underlying compartmentalization of JS-associated ARL13B/ARL-13, which we previously found is restricted at proximal ciliary membranes. We now show evolutionary conservation of ARL13B/ARL-13 localisation to an Inv-like subciliary membrane compartment, excluding the TZ, in many C. elegans ciliated neurons and in a subset of mammalian ciliary subtypes. Compartmentalisation of C. elegans ARL-13 requires a C-terminal RVVP motif and membrane anchoring to prevent distal cilium and nuclear targeting, respectively. Quantitative imaging in more than 20 mutants revealed differential contributions for IFT and ciliopathy modules in defining the ARL-13 compartment; IFT-A/B, IFT-dynein and BBS genes prevent ARL-13 accumulation at periciliary membranes, whereas MKS/NPHP modules additionally inhibit ARL-13 association with TZ membranes. Furthermore, in vivo FRAP analyses revealed distinct roles for IFT and MKS/NPHP genes in regulating a TZ barrier to ARL-13 diffusion, and intraciliary ARL-13 diffusion. Finally, C. elegans ARL-13 undergoes IFT-like motility and quantitative protein complex analysis of human ARL13B identified functional associations with IFT-B complexes, mapped to IFT46 and IFT74 interactions. Together, these findings reveal distinct requirements for sequence motifs, IFT and ciliopathy modules in defining an ARL-13 subciliary membrane compartment. We conclude that MKS/NPHP modules comprise a TZ barrier to ARL-13 diffusion, whereas IFT genes predominantly facilitate ARL-13 ciliary entry and/or retention via active transport mechanisms. 相似文献
995.
Ivaylo Vassilev Anne Rogers Christian Blickem Helen Brooks Dharmi Kapadia Anne Kennedy Caroline Sanders Sue Kirk David Reeves 《PloS one》2013,8(4)
Self-management support forms a central aspect of chronic Illness management nationally and globally. Evidence for the success of self-management support has mainly focussed on individually-centred outcomes of behavioural change. While it is recognised that social network members play an important role there is currently a gap in knowledge regarding who provides what type of support and under what circumstances. This is relevant for understanding the division of labour and the meeting of needs for those living with a long-term condition. We therefore took a network approach to explore self-management support conceptualising it as types of illness ‘work’ undertaken within peoples’ social networks. 300 people from deprived areas and with chronic illnesses took part in a survey conducted in 2010 in the North West of England. A concentric circles diagram was used as a research tool with which participants identified 2,544 network members who contributed to illness management. The results provide an articulation of how social network members are substantially involved in illness management. Whilst partners and close family make the highest contributions there is evidence of inputs from a wide range of relationships. Network member characteristics (type of relationship, proximity, frequency of contact) impact on the amount of illness work undertaken in peoples’ networks. In networks with ‘no partner’ other people tend to contribute more in the way of illness related work than in networks with a partner. This indicates a degree of substitutability between differently constituted networks, and that the level and type of input by different members of a network might change according to circumstances. A network perspective offers an opportunity to redress the balance of an exclusively individual focus on self-management because it addresses the broader set of contributions and resources available to people in need of chronic illness management and support. 相似文献
996.
Nathan F. Bendik Thomas A. Morrison Andrew G. Gluesenkamp Mark S. Sanders Lisa J. O’Donnell 《PloS one》2013,8(3)
Despite recognition that nearly one-third of the 6300 amphibian species are threatened with extinction, our understanding of the general ecology and population status of many amphibians is relatively poor. A widely-used method for monitoring amphibians involves injecting captured individuals with unique combinations of colored visible implant elastomer (VIE). We compared VIE identification to a less-invasive method – computer-assisted photographic identification (photoID) – in endangered Jollyville Plateau salamanders (Eurycea tonkawae), a species with a known range limited to eight stream drainages in central Texas. We based photoID on the unique pigmentation patterns on the dorsal head region of 1215 individual salamanders using identification software Wild-ID. We compared the performance of photoID methods to VIEs using both ‘high-quality’ and ‘low-quality’ images, which were taken using two different camera types and technologies. For high-quality images, the photoID method had a false rejection rate of 0.76% compared to 1.90% for VIEs. Using a comparable dataset of lower-quality images, the false rejection rate was much higher (15.9%). Photo matching scores were negatively correlated with time between captures, suggesting that evolving natural marks could increase misidentification rates in longer term capture-recapture studies. Our study demonstrates the utility of large-scale capture-recapture using photo identification methods for Eurycea and other species with stable natural marks that can be reliably photographed. 相似文献
997.
Maryam Al-Hilal Aseel AlSaleh Zoitsa Maniou Fiona J. Lewis Wendy L. Hall Thomas A. B. Sanders Sandra D. O'Dell 《Journal of lipid research》2013,54(2):542-551
Delta-5 and delta-6 desaturases (D5D and D6D) are key enzymes in endogenous synthesis of long-chain PUFAs. In this sample of healthy subjects (n = 310), genotypes of single nucleotide polymorphisms (SNPs) rs174537, rs174561, and rs3834458 in the FADS1-FADS2 gene cluster were strongly associated with proportions of LC-PUFAs and desaturase activities estimated in plasma and erythrocytes. Minor allele carriage associated with decreased activities of D5D (FADS1) (5.84 × 10−19 ≤ P ≤ 4.5 × 10−18) and D6D (FADS2) (6.05 × 10−8 ≤ P ≤ 4.20 × 10−7) was accompanied by increased substrate and decreased product proportions (0.05 ≤ P ≤ 2.49 × 10−16). The significance of haplotype association with D5D activity (P = 2.19 × 10−17) was comparable to that of single SNPs, but haplotype association with D6D activity (P = 3.39 × 10−28) was much stronger. In a randomized controlled dietary intervention, increasing eicosapentaenoic acid (EPA, 20:5n-3) and docosahexaenoic acid (DHA, 22:6n-3) intake significantly increased D5D (P = 4.0 × 10−9) and decreased D6D activity (P = 9.16 × 10−6) after doses of 0.45, 0.9, and 1.8 g/day for six months. Interaction of rs174537 genotype with treatment was a determinant of D5D activity estimated in plasma (P = 0.05). In conclusion, different sites at the FADS1-FADS2 locus appear to influence D5D and D6D activity, and rs174537 genotype interacts with dietary EPA+DHA to modulate D5D. 相似文献
998.
Coexpression Networks Implicate Human Midfetal Deep Cortical Projection Neurons in the Pathogenesis of Autism 总被引:1,自引:0,他引:1
A. Jeremy Willsey Stephan J. Sanders Mingfeng Li Shan Dong Andrew T. Tebbenkamp Rebecca A. Muhle Steven K. Reilly Leon Lin Sofia Fertuzinhos Jeremy A. Miller Michael T. Murtha Candace Bichsel Wei Niu Justin Cotney A. Gulhan Ercan-Sencicek Jake Gockley Abha R. Gupta Wenqi Han Xin He Ellen J. Hoffman Lambertus Klei Jing Lei Wenzhong Liu Li Liu Cong Lu Xuming Xu Ying Zhu Shrikant M. Mane Ed S. Lein Liping Wei James P. Noonan Kathryn Roeder Bernie Devlin Nenad Sestan Matthew W. State 《Cell》2013
999.
Previously unreported dasycladaleans and one morpho-taxon of assumed algal origin are described from Upper Turonian to Santonian rocks of the Lower Gosau Subgroup (LGS) of the Northern Calcareous Alps. A taxonomic inventory of green-algal/benthic foraminiferal assemblages shows that assemblages of “pure” carbonate environments are more diverse than those of siliciclastic and mixed siliciclastic-carbonate settings. A comparison of the taxonomic inventory of the LGS with assemblages in similar sedimentary successions of the Alpine-Mediterranean realm shows the highest similarity with the “Mirdita Zone” of the internal Dinarids. Comparability of assemblages, however, is limited due to narrow chronostratigraphic overlap and/or because of scarcity of data from areas outside the Alps. Although higher than previously known, the total diversity of the green-algal/benthic foraminiferal assemblage of the LGS is clearly inferior to that of the peri-Adriatic carbonate platforms. 相似文献
1000.
Webb Siobhan L. Sanders Andrew J. Mason Malcolm D. Jiang Wen G. 《Molecular and cellular biochemistry》2013,377(1-2):207-218
Ezrin, primarily acts as a linker between the plasma membrane and the cytoskeleton, is involved in many cellular functions, including regulation of actin cytoskeleton, control of cell shape, adhesion, motility, and modulation of signaling pathways. Although ezrin is now recognized as a key component in tumor metastasis, its roles and the underlying mechanisms remain unclear. In the present study, we chose highly metastatic human lung carcinoma 95D cells, which highly express the ezrin proteins, as a model to examine the functional roles of ezrin in tumor suppression. An ezrin-silenced 95D cell line was established using lentivirus-mediated short hairpin RNA method. CCK-8 assay and soft agar assay analysis showed that downregulation of ezrin significantly suppressed the tumorigenicity and proliferation of 95D cells in vitro. cell migration and invasion studies showed that ezrin-specific deficiency in the cells caused the substantial reduction of the cell migration and invasion. In parallel, it also induced rearrangements of the actin cytoskeleton. Flow cytometry assay showed that changes in the ezrin protein level significantly affected the cell cycle distribution and eventual apoptosis. Furthermore, further studies showed that ezrin regulated the expression level of E-cadherin and CD44, which are key molecules involved in cell growth, migration, and invasion. Meanwhile, the suppression of ezrin expression also sensitized cells to antitumor drugs. Altogether, our results demonstrated that ezrin played an important role in the tumorigenicity and metastasis of lung cancer cells, which will benefit the development of therapeutic strategy for lung cancer. 相似文献