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81.
Jesse de Metz Johannes A Romijn Erik Endert Mariette T Ackermans Gerrit Jan Weverling Olivier R Busch Laurence Th de Wit Dirk J Gouma Ineke J M ten Berge Hans P Sauerwein 《Journal of applied physiology》2004,96(2):597-603
Tissue injury is associated with decreased cellular immunity and enhanced metabolism. Immunodepression is thought to be counteracted by interferon (IFN)-gamma, which increases human leukocyte antigen (HLA)-DR expression. Hypermetabolism could be enhanced by IFN-gamma because cytokines induce a hypermetabolic response to stress. In healthy humans, IFN-gamma enhanced HLA-DR expression without effects on glucose and fat metabolism. In the present study, we evaluated whether IFN-gamma lacks potential harmful side effects on metabolic and endocrine pathways while maintaining its beneficial effects on the immune system under conditions in which the inflammatory response system is activated. In 13 patients scheduled for major surgery, we studied HLA-DR expression on peripheral blood monocytes before surgery and postoperatively randomized the patients into an intervention and a placebo group. Subsequently, we evaluated the effects of a single dose of IFN-gamma vs. saline on short-term monocyte activation, glucose and lipid metabolism, and glucose and lipid regulatory hormones. HLA-DR expression on monocytes was restored from postoperative levels of 54% (42-60%; median and interquartiles) to 92% (91-96%) 24 h after IFN-gamma administration but stayed low in the placebo-treated patients. IFN-gamma did not affect glucose metabolism (plasma glucose, rate of appearance and disappearance of glucose) and lipid metabolism (plasma glycerol, plasma free fatty acids, and rates of appearance and disappearance of glycerol). IFN-gamma had no effect on plasma cortisol, adrenocorticotropic hormone, growth hormone, insulin, C-peptide, glucagon, epinephrine, and norepinephrine concentrations. We conclude that IFN-gamma exerts a favorable effect on cell-mediated immunity in patients after major surgery without effects on glucose and lipid metabolism. 相似文献
82.
William G. Ambrose Jr. Paul E. Renaud William L. Locke V Finlo R. Cottier J?rgen Berge Michael L. Carroll Benjamin Levin Stuart Ryan 《Polar Biology》2012,35(3):345-354
Growth patterns of two common circumpolar bivalves, the Greenland cockle (Serripes groenlandicus), and the hairy cockle (Clinocardium ciliatum) have been used in previous studies to reconstruct environmental conditions in the arctic. To date, there has been no direct
determination that growth lines in either species are deposited periodically, and there has been no examination of factors
affecting growth. We placed calcein-marked individuals of both species on oceanographic moorings in two fjords (Rijpfjord
and Kongsfjord) in the Svalbard archipelago for one and two (Kongsfjord only) years. Growth patterns were compared with concurrent
in situ temperature and fluorescence data in order to assess environmental controls on growth. Dark growth lines are evident
on the outer shell surface and internally in shell cross section in both S. groenlandicus and C. ciliatum, and both species deposited only one line per year, unequivocally confirming that internal lines are deposited annually. Growth
line deposition in both species began in late summer to early fall, before the seasonal decline in temperature. There was
no difference in growth of S. groenlandicus between the two fjords despite differences in water temperature (3°C), fluorescence (nearly threefold) and the onset and
duration of the winter season. C. ciliatum, however, grew approximately 2.8 times faster in the warmer, more food-rich Kongsfjord than in Rijpfjord. Subannual lines
were counted in two individuals of each species from each fjord, but deposition of these lines was not clearly related to
number of growing days estimated by temperature and fluorescence. 相似文献
83.
84.
Pablo Ferreira das Chagas Mirella Baroni María Sol Brassesco Luiz Gonzaga Tone 《The journal of gene medicine》2020,22(1)
Musashi comprises an evolutionarily conserved family of RNA‐binding proteins (RBP) that regulate cell fate decisions during embryonic development and play key roles in the maintenance of self‐renewal and differentiation of stem cells and adult tissues. More recently, several studies have shown that any dysregulation of MSI1 and MSI2 can lead to cellular dysfunctions promoting tissue instability and tumorigenesis. Moreover, several reports have characterized many molecular interactions between members of the Musashi family with ligands and receptors of the signaling pathways responsible for controlling normal embryonic development: Notch, Transforming Growth Factor Beta (TGF‐β), Wingless (Wnt) and Hedgehog Signaling (Hh); all of which, when altered, are strongly associated with cancer onset and progression, especially in pediatric tumors. In this context, the present review aims to compile possible cross‐talks between Musashi proteins and members of the above cited molecular pathways for which dysregulation plays important roles during carcinogenesis and may be modulated by these RBP. 相似文献
85.
Kapić S Cipčić Paljetak H Palej Jakopović I Fajdetić A Ilijaš M Stimac V Brajša K Holmes DJ Berge J Alihodžić S 《Bioorganic & medicinal chemistry》2011,19(23):7281-7298
Three macrolides, clarithromycin, azithromycin and 11-O-Me-azithromycin have been selected for the construction of a series of new macrolone derivatives. Quinolone-linker intermediates are prepared by Sonogashira-type C(6)-alkynylation of 6-iodoquinolone precursors. The final macrolones, differing by macrolide moiety and substituents at the position N-1 of the quinolone or by the presence of an ethyl ester or free acid on the quinolone unit attached via a linker. The linker comprises of a central piperazine ring bonded to the 4″-O position of cladinose by 3-carbon ester or ether functionality. Modifications of the linker did not improve antibacterial properties compared to the previously reported macrolone compounds. Linker flexibility seems to play an important role for potency against macrolide resistant respiratory pathogens. 相似文献
86.
Tone Novak Tina Tkavc Matja Kuntner Amy E. Arnett Saka Lipovek Delakorda Matja Perc Franc Janekovi
《Acta Oecologica》2010,36(6):522
Hypogean habitats are relatively simple exhibiting low diversity, low production and relative constancy of environmental factors, and are therefore appropriate for studying species coexistence in situ. We investigated the coexistence of two closely related, similarly sized orb-weaving spider species, Meta menardi and Metellina merianae, living syntopically in a Slovenian cave. We studied the annual dynamics of both species within a mixed population, and the impact of the ambient temperature, relative humidity, airflow and illumination, and compared their trophic niches to legacy data on prey of both species from 55 caves in Slovenia. We predicted a large overlap in their spatial niches and substantial differences in their temporal and trophic niches. We found that their spatial niches overlap greatly with few exceptions, mostly on the dates of notable meteorological changes in the cave but that their temporal niches differ significantly with r-strategy resembling epigean annual dynamic in M. merianae and a steady low abundance course in M. menardi within the cave. We also found that different predatory strategies significantly segregate their trophic niches: M. merianae uses a typical orb-weaving hunting strategy, while M. menardi combines web hunting with off-web hunting. Our findings suggest that both the diverse dynamics and trophic niches enable the coexistence of M. menardi and M. merianae despite their similar spatial niches, and that M. menardi, in particular, is optimally adapted to the epigean/hypogean ecotone. 相似文献
87.
Jarrod Gott Leonore Bovy Emma Peters Sofia Tzioridou Stefano Meo aatay Demirel Mahdad Jafarzadeh Esfahani Pedro Reis Oliveira Thomas Houweling Alessandro Orticoni Anke Rademaker Diede Booltink Rathiga Varatheeswaran Carmen van Hooijdonk Mahmoud Chaabou Anastasia Mangiaruga Erik van den Berge Frederik D. Weber Simone Ritter Martin Dresler 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2021,376(1817)
Metacognitive reflections on one''s current state of mind are largely absent during dreaming. Lucid dreaming as the exception to this rule is a rare phenomenon; however, its occurrence can be facilitated through cognitive training. A central idea of respective training strategies is to regularly question one''s phenomenal experience: is the currently experienced world real, or just a dream? Here, we tested if such lucid dreaming training can be enhanced with dream-like virtual reality (VR): over the course of four weeks, volunteers underwent lucid dreaming training in VR scenarios comprising dream-like elements, classical lucid dreaming training or no training. We found that VR-assisted training led to significantly stronger increases in lucid dreaming compared to the no-training condition. Eye signal-verified lucid dreams during polysomnography supported behavioural results. We discuss the potential mechanisms underlying these findings, in particular the role of synthetic dream-like experiences, incorporation of VR content in dream imagery serving as memory cues, and extended dissociative effects of VR session on subsequent experiences that might amplify lucid dreaming training during wakefulness.This article is part of the theme issue ‘Offline perception: voluntary and spontaneous perceptual experiences without matching external stimulation''. 相似文献
88.
Yousra?Bouaoud Claire?Troulet Abdelhamid?Foughalia Odile?Berge Kamel?Aissat Marc?BardinEmail author 《BioControl》2018,63(2):299-311
In order to find biocontrol agents that are both efficient against Botrytis cinerea Pers. and adapted to tomato growing conditions in Algeria, 121 bacterial strains were collected from tomato plants and nearby soils in two Bejaia greenhouses. A total of 37 strains were selected based on their ability to grow on agar medium and on their different level of B. cinerea mycelial growth inhibition in dual-culture tests. These strains were identified at the species level and those that corresponded to potential pathogens for humans or mammals were discarded. Among the remaining 25 candidates, three strains were selected among the Pseudomonas genus for their significant protective efficacy against B. cinerea on tomato, their ability to grow at 15–25 °C and their inability to grow at 37 °C. These three strains significantly reduced the development of necrotic lesion and the sporulation of B. cinerea in a dose-dependent manner. This study constitutes a first step towards the biological control of B. cinerea in tomato greenhouses in Algeria. 相似文献
89.
Intracellular localization of long-chain acyl-coenzyme A hydrolase and acyl-L-carnitine hydrolase in brown adipose tissue from guinea pigs. 下载免费PDF全文
The activities of long-chain acyl-CoA hydrolase (palmitoyl-CoA hydrolase, EC 3.1.2.2) and long-chain acyl-L-carnitine hydrolase, EC 3.1.1.28) in brown adipose tissue from cold-exposed and control guinea pigs were studied. Mitochondria from cold-exposed animals hydrolysed 21 nmol of palmitoyl-CoA/min per mg of protein and 1.3 nmol of palmitoyl-L-carnitine/min per mg of protein, and the specific activities were respectively 2 and 5 times as high in cold-exposed as in control animals. The subcellular-localization studies showed that both the long-chain acyl-CoA hydrolase and long-chain acyl-L-carnitine hydrolase were localized in the mitochondria. A location also in the soluble fraction cannot be excluded. The long-chain acyl-CoA hydrolase activity was doubled when the mitochondria were disrupted; this indicates that the enzyme is localized in the matrix compartment. 相似文献
90.
In order to compare gait patterns, a common procedure is to normalize strides both in time and magnitude. The stride duration is usually normalized to a time percentage before averaging curves. As the timing of event occurrences may shift across strides, the shape of the averaged curves is distorted and therefore the standard deviation is overvalued. Stride magnitude normalization is performed by means of dimensionless numbers. However, there is little agreement on which body size correction methods should be used. The Procrustes method describes curve shape and shape change in a mathematical and statistical framework, independently of time and size factors. The present study aims to explore how this technique may be used for time- and magnitude-stride normalization to reflect individual and group mean responses. The Procrustes method, which combines quantitative and visual features, is applied to the shape of the ankle and knee cyclograms. Superimposition of 25 cyclograms (10 for sprinters (SP) and 15 for middle-distance runners (MDR)) was supplemented by statistical procedures (principal component analysis, discriminant function) to extract the main key events, which vary according to the athletic specialities. In comparison with the MDR (poulaine-shaped cyclogram), the ovoid cyclogram of SP reveals the following gait indicators: a short braking phase, a rapid initial lower limb swing in the forward direction, a fast upward movement of the knee and ankle, and an active foot contact. The Procrustes approach could be used to describe other quasi-periodic movements through relative motion plots (e.g., cyclograms, angle-angle diagrams, phase plane portraits). 相似文献