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991.
Jian Ma Yi-Dong Zhang Li-Guo Ma Shou-Cai Ren Rafael F. Casta?eda-Ruíz Xiu-Guo Zhang 《Mycological Progress》2012,11(3):639-645
Three previously undescribed Solicorynespora species were collected from tropical forests in Hainan Province, China. S. melicopes sp. nov., S. linderae sp. nov. and S. fici sp. nov. are described and illustrated from specimens collected on dead branches of Melicope triphylla, Lindera communis and Ficus auriculata, respectively. They are compared with closely related taxa. A dichotomous key and a synoptic table to Solicorynespora species are provided. 相似文献
992.
993.
González S Moreno-Delgado D Moreno E Pérez-Capote K Franco R Mallol J Cortés A Casadó V Lluís C Ortiz J Ferré S Canela E McCormick PJ 《PLoS biology》2012,10(6):e1001347
The role of the pineal gland is to translate the rhythmic cycles of night and day encoded by the retina into hormonal signals that are transmitted to the rest of the neuronal system in the form of serotonin and melatonin synthesis and release. Here we describe that the production of both melatonin and serotonin by the pineal gland is regulated by a circadian-related heteromerization of adrenergic and dopamine D4 receptors. Through α1
B-D4 and β1-D4 receptor heteromers dopamine inhibits adrenergic receptor signaling and blocks the synthesis of melatonin induced by adrenergic receptor ligands. This inhibition was not observed at hours of the day when D4 was not expressed. These data provide a new perspective on dopamine function and constitute the first example of a circadian-controlled receptor heteromer. The unanticipated heteromerization between adrenergic and dopamine D4 receptors provides a feedback mechanism for the neuronal hormone system in the form of dopamine to control circadian inputs. 相似文献
994.
Federico Vaggi James Dodgson Archana Bajpai Anatole Chessel Ferenc Jordán Masamitsu Sato Rafael Edgardo Carazo-Salas Attila Csikász-Nagy 《PLoS computational biology》2012,8(10)
The study of gene and protein interaction networks has improved our understanding of the multiple, systemic levels of regulation found in eukaryotic and prokaryotic organisms. Here we carry out a large-scale analysis of the protein-protein interaction (PPI) network of fission yeast (Schizosaccharomyces pombe) and establish a method to identify ‘linker’ proteins that bridge diverse cellular processes - integrating Gene Ontology and PPI data with network theory measures. We test the method on a highly characterized subset of the genome consisting of proteins controlling the cell cycle, cell polarity and cytokinesis and identify proteins likely to play a key role in controlling the temporal changes in the localization of the polarity machinery. Experimental inspection of one such factor, the polarity-regulating RNB protein Sts5, confirms the prediction that it has a cell cycle dependent regulation. Detailed bibliographic inspection of other predicted ‘linkers’ also confirms the predictive power of the method. As the method is robust to network perturbations and can successfully predict linker proteins, it provides a powerful tool to study the interplay between different cellular processes. 相似文献
995.
Ashrafian H Czibik G Bellahcene M Aksentijević D Smith AC Mitchell SJ Dodd MS Kirwan J Byrne JJ Ludwig C Isackson H Yavari A Støttrup NB Contractor H Cahill TJ Sahgal N Ball DR Birkler RI Hargreaves I Tennant DA Land J Lygate CA Johannsen M Kharbanda RK Neubauer S Redwood C de Cabo R Ahmet I Talan M Günther UL Robinson AJ Viant MR Pollard PJ Tyler DJ Watkins H 《Cell metabolism》2012,15(3):361-371
996.
Frank W. Albert Mehmet Somel Miguel Carneiro Ayinuer Aximu-Petri Michel Halbwax Olaf Thalmann Jose A. Blanco-Aguiar Irina Z. Plyusnina Lyudmila Trut Rafael Villafuerte Nuno Ferrand Sylvia Kaiser Per Jensen Svante P??bo 《PLoS genetics》2012,8(9)
Domestication has led to similar changes in morphology and behavior in several animal species, raising the question whether similarities between different domestication events also exist at the molecular level. We used mRNA sequencing to analyze genome-wide gene expression patterns in brain frontal cortex in three pairs of domesticated and wild species (dogs and wolves, pigs and wild boars, and domesticated and wild rabbits). We compared the expression differences with those between domesticated guinea pigs and a distant wild relative (Cavia aperea) as well as between two lines of rats selected for tameness or aggression towards humans. There were few gene expression differences between domesticated and wild dogs, pigs, and rabbits (30–75 genes (less than 1%) of expressed genes were differentially expressed), while guinea pigs and C. aperea differed more strongly. Almost no overlap was found between the genes with differential expression in the different domestication events. In addition, joint analyses of all domesticated and wild samples provided only suggestive evidence for the existence of a small group of genes that changed their expression in a similar fashion in different domesticated species. The most extreme of these shared expression changes include up-regulation in domesticates of SOX6 and PROM1, two modulators of brain development. There was almost no overlap between gene expression in domesticated animals and the tame and aggressive rats. However, two of the genes with the strongest expression differences between the rats (DLL3 and DHDH) were located in a genomic region associated with tameness and aggression, suggesting a role in influencing tameness. In summary, the majority of brain gene expression changes in domesticated animals are specific to the given domestication event, suggesting that the causative variants of behavioral domestication traits may likewise be different. 相似文献
997.
Gabrieli L. Parrilha Rafael P. Vieira Paula P. Campos Grácia Divina F. Silva Lucienir P. Duarte Silvia P. Andrade Heloisa Beraldo 《Biometals》2012,25(1):55-62
Complex [Bi(Lp)2]Cl was obtained with 4-hydroxy-3-(3-methylbut-2-enyl)naphthalene-1,2-dione, “lapachol” (HLp). Lapachol, [Bi(Lp)2]Cl and BiCl3 were evaluated in a murine model of inflammatory angiogenesis induced by subcutaneous implantation of polyether polyurethane
sponge discs. Intraperitoneal (i.p.) administration of lapachol or [Bi(Lp)2]Cl reduced the hemoglobin content in the implants suggesting that reduction of neo-vascularization was caused by lapachol.
In the per os treatment only [Bi(Lp)2]Cl decreased the hemoglobin content in the implants. Likewise, N-acetylglucosaminidase (NAG) activity decreased in the implants of the groups i.p. treated with lapachol and [Bi(Lp)2]Cl while in the per os treatment inhibition was observed only for [Bi(Lp)2]Cl. Histological analysis showed that the components of the fibro-vascular tissue (vascularization and inflammatory cell
population) were decreased in lapachol- and complex-treated groups. Our results suggest that both lapachol and [Bi(Lp)2]Cl exhibit anti-angiogenic and anti-inflammatory activities which have been attributed to the presence of the lapachol ligand.
However, coordination to bismuth(III) could be an interesting strategy for improvement of lapachol’s therapeutic properties. 相似文献
998.
Kate L Holliday Wendy Thomson Tuhina Neogi David T Felson Ke Wang Frederick C Wu Ilpo T Huhtaniemi Gyorgy Bartfai Felipe Casanueva Gianni Forti Krzysztof Kula Margus Punab Dirk Vanderschueren Gary J Macfarlane Michael A Horan William Ollier Antony Payton Neil Pendleton John McBeth 《Molecular pain》2012,8(1):1-5
Background
Chronic pain conditions are characterized by significant individual variability complicating the identification of pathophysiological markers. Leukocyte telomere length (TL), a measure of cellular aging, is associated with age-related disease onset, psychosocial stress, and health-related functional decline. Psychosocial stress has been associated with the onset of chronic pain and chronic pain is experienced as a physical and psychosocial stressor. However, the utility of TL as a biological marker reflecting the burden of chronic pain and psychosocial stress has not yet been explored.Findings
The relationship between chronic pain, stress, and TL was analyzed in 36 ethnically diverse, older adults, half of whom reported no chronic pain and the other half had chronic knee osteoarthritis (OA) pain. Subjects completed a physical exam, radiographs, health history, and psychosocial questionnaires. Blood samples were collected and TL was measured by quantitative polymerase chain reaction (qPCR). Four groups were identified characterized by pain status and the Perceived Stress Scale scores: 1) no pain/low stress, 2) no pain/high stress, chronic pain/low stress, and 4) chronic pain/high stress. TL differed between the pain/stress groups (p = 0.01), controlling for relevant covariates. Specifically, the chronic pain/high stress group had significantly shorter TL compared to the no pain/low stress group. Age was negatively correlated with TL, particularly in the chronic pain/high stress group (p = 0.03).Conclusions
Although preliminary in nature and based on a modest sample size, these findings indicate that cellular aging may be more pronounced in older adults experiencing high levels of perceived stress and chronic pain. 相似文献999.
M Armayones MA Vilaseca J Cutillas J Fàbrega JJ Fernández M García N Egea M Pousada B Gómez-Zuñiga J Pérez-Payarols R Artuch F Palau M Serrano 《Orphanet journal of rare diseases》2012,7(1):53
ABSTRACT: Web-based interventions are effective on the patient empowerment. Guiametabolica.org constitutes an interface for people involved in inherited metabolic diseases, trying to facilitate access to information and contact with professionals and other patients, offering a platform to develop support groups. Guiametabolica.org is widely considered for Spanish-speaking patients and caregivers with inherited metabolic diseases. Preliminary evaluations show changes in their habits, decrease in their senses of isolation and improvement regarding self-efficacy. Specific inherited metabolic diseases websites, especially participative websites, should be considered as a complement to more traditional clinical approaches. Their contribution lies in patient's general well-being, without interfering with traditional care. 相似文献
1000.
This protocol requires 2-4 h and presents a method for injecting tumor cells, cancer stem cells or dispersed biopsy material into subcutaneous or orthotopic locations within recipient mice. The tumor cells or biopsy are mixed with basement membrane matrix proteins (CultrexBME or Matrigel) at 4 °C and then injected into recipient animals at preferred anatomical sites. Tumor cells can also be co-injected with additional cell types, such as fibroblasts, stromal cells, endothelial cells and so on. Details are given on appropriate cell numbers, handling and concentration of the basement membrane proteins, recipient animals, injection location and techniques. This procedure enables the growth of tumors from cells or biopsy material (tumor graft) with greater efficiency of take and growth, and with retention of the primary tumor phenotype based on histology. Co-injection with additional cell types provides more physiological models of human cancers for use in drug screening and studying cancer biology. 相似文献