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31.
Corals as light collectors: an integrating sphere approach 总被引:3,自引:3,他引:0
An integrating sphere was used to estimate the fraction of the incident quantum flux absorbed by a coral colony placed within it. This method allows one to examine the in vivo light absorption of intact coral colonies. We used this method to study effects of colony morphology, size, and photoacclimation status on the light harvesting efficiency by the zooxanthellae. Light absorption per unit of coral surface area decreased with increase in colony size, with a clear effect of different coral morphologies. In branched colonies, shading among branches reduced the absorbed light per unit area and per zooxanthellae. Photoacclimation to low light resulted in increased cellular chlorophyll concentrations in the zooxanthellae. In shade acclimated colonies, areal chlorophyll concentrations increased significantly, leading to more overlap among the optical cross-sections of pigments within cells and mutual shading among cells. These package effects showed up as a decrease in the in vivo, chlorophyll-a specific, spectral average, effective optical cross-section, a*. An integrating sphere is a useful tool for collecting optical information on corals. 相似文献
32.
Bonar E Dubin A Bierczyńska-Krzysik A Noga M Silberring J Stalińska K Koj A 《Cytokine》2006,33(2):111-117
Interleukin-1 (IL-1) and interleukin-6 (IL-6) are principal proinflammatory cytokines inducing the acute phase response of various tissues, including liver. Cultured human hepatoma HepG2 cells were stimulated with IL-1 (10 ng/ml) and IL-6 (10 ng/ml). After 24 h the cells were collected and disrupted by sonication in a lysis buffer containing 8M urea. The extracted cellular proteins were separated by 2D polyacrylamide gel electrophoresis. The gels were stained with Coomassie Brilliant Blue R-250 and the protein spots showing different intensities in comparison to control (unstimulated) cells were excised and subjected to analysis by LC-MS/MS. Alternatively, proteins were stained with SYPRO Ruby. These differentially expressed proteins include seven up-regulated and two down-regulated intracellular proteins of various functions. The identification of three cytokine-responsive proteins was confirmed by biosynthetic labeling with [35S]methionine after incubation of HepG2 cells, and by western blot with specific antisera. 相似文献
33.
Antonella De Jaco Michael Z. Lin Noga Dubi Davide Comoletti Meghan T. Miller Shelley Camp Mark Ellisman Margaret T. Butko Roger Y. Tsien Palmer Taylor 《The Journal of biological chemistry》2010,285(37):28674-28682
Despite great functional diversity, characterization of the α/β-hydrolase fold proteins that encompass a superfamily of hydrolases, heterophilic adhesion proteins, and chaperone domains reveals a common structural motif. By incorporating the R451C mutation found in neuroligin (NLGN) and associated with autism and the thyroglobulin G2320R (G221R in NLGN) mutation responsible for congenital hypothyroidism into NLGN3, we show that mutations in the α/β-hydrolase fold domain influence folding and biosynthetic processing of neuroligin3 as determined by in vitro susceptibility to proteases, glycosylation processing, turnover, and processing rates. We also show altered interactions of the mutant proteins with chaperones in the endoplasmic reticulum and arrest of transport along the secretory pathway with diversion to the proteasome. Time-controlled expression of a fluorescently tagged neuroligin in hippocampal neurons shows that these mutations compromise neuronal trafficking of the protein, with the R451C mutation reducing and the G221R mutation virtually abolishing the export of NLGN3 from the soma to the dendritic spines. Although the R451C mutation causes a local folding defect, the G221R mutation appears responsible for more global misfolding of the protein, reflecting their sequence positions in the structure of the protein. Our results suggest that disease-related mutations in the α/β-hydrolase fold domain share common trafficking deficiencies yet lead to discrete congenital disorders of differing severity in the endocrine and nervous systems. 相似文献
34.
Rat brain proteome in morphine dependence 总被引:4,自引:0,他引:4
Bierczynska-Krzysik A Bonar E Drabik A Noga M Suder P Dylag T Dubin A Kotlinska J Silberring J 《Neurochemistry international》2006,49(4):401-406
The aim of this study was to reveal potential markers associated with drug dependence, using the proteomic approach. Gels containing samples derived from morphine-treated and control animals were compared and analyzed. Inspection of protein profiles, following TCA/acetone precipitation and the use of nano-scale liquid chromatography coupled to tandem mass spectrometry, allowed for identification of eleven potential dependence markers, mainly cytoplasmic and mitochondrial enzymes, e.g. proteins that belong to GTPase and GST superfamilies, ATPase, asparaginase or proteasome subunit p27 families. 相似文献
35.
Vandersea MW Litaker RW Yonnish B Sosa E Landsberg JH Pullinger C Moon-Butzin P Green J Morris JA Kator H Noga EJ Tester PA 《Applied and environmental microbiology》2006,72(2):1551-1557
The pathogenic oomycete Aphanomyces invadans is the primary etiological agent in ulcerative mycosis, an ulcerative skin disease caused by a fungus-like agent of wild and cultured fish. We developed sensitive PCR and fluorescent peptide nucleic acid in situ hybridization (FISH) assays to detect A. invadans. Laboratory-challenged killifish (Fundulus heteroclitus) were first tested to optimize and validate the assays. Skin ulcers of Atlantic menhaden (Brevoortia tyrannus) from populations found in the Pamlico and Neuse River estuaries in North Carolina were then surveyed. Results from both assays indicated that all of the lesioned menhaden (n = 50) collected in September 2004 were positive for A. invadans. Neither the FISH assay nor the PCR assay cross-reacted with other closely related oomycetes. These results provided strong evidence that A. invadans is the primary oomycete pathogen in ulcerative mycosis and demonstrated the utility of the assays. The FISH assay is the first molecular assay to provide unambiguous visual confirmation that hyphae in the ulcerated lesions were exclusively A. invadans. 相似文献
36.
Antimicrobial peptides (AMPs) are increasingly recognized as a critical component of the host's defense against infection. Several types of AMPs have been recently identified from mucosal tissues or immune cells of a number of teleosts. Among these are the piscidins, which are 22 residue, alpha-helical AMPs that were originally isolated from mast cells of hybrid striped bass Morone saxatilis male x Morone chrysops female. Using an antibody specific for the conserved N-terminal amino acid sequence of piscidin 1, we used immunohistochemistry to probe skin, gill, and gastrointestinal tract of 39 teleosts representing 7 different orders. Nine fish species were piscidin-positive, with all of these species being in the Perciformes, the largest and most evolutionarily advanced order of teleosts. Piscidin-positive cells were identified in species belonging to the families Moronidae, Serranidae, Sciaenidae, Siganidae and Belontidae. Immunopositive cells were usually most consistent with mast cells, although in some species, the granule appearance and tinctorial properties diverged somewhat from those of a typical piscine mast cell. In addition, rodlet cells were piscidin-positive in one member of the family Cichlidae; to our knowledge, it is the first time that a host-associated chemical biomarker has been identified in rodlet cells. Our data suggest that piscidins are present in many evolutionarily advanced teleosts. Piscidin-immunoreactive cells were most common at sites of pathogen entry, including the skin, gill and gastrointestinal tract. These results strongly suggest that piscidins are a widespread and important component of many fishes' defense against disease. 相似文献
37.
38.
Gal N Malferarri D Kolusheva S Galletti P Tagliavini E Jelinek R 《Biochimica et biophysica acta》2012,1818(12):2967-2974
Ionic liquids (ILs) are a class of diverse organic salts with relatively low melting points (below 100°C) which have attracted considerable interest as a promising "green" substitute for organic solvents. The broad solvation properties of ILs and their high solubility in water, however, present health risks, in particular since it was shown that many ILs exhibit cytotoxic properties. In this context, interactions of ILs with the cellular membrane are believed to constitute a primary culprit for toxicity. We present a comprehensive biophysical and microscopy study of membrane interactions of a series of ILs having different side-chain compositions and lengths, and cationic head-group structures and orientations. The experimental data reveal that the ILs studied exhibit distinct mechanisms of membrane binding, insertion, and disruption which could be correlated with their biological activities. The results indicate, in particular, that both the side chain composition and particularly the head-groups of ILs constitute determinants for membrane activity and consequent cell toxicity. This work suggests that tuning membrane interactions of ILs should be an important factor for designing future compounds with benign environmental impact. 相似文献
39.
Noga Kronfeld-Schor Davide Dominoni Horacio de la Iglesia Oren Levy Erik D. Herzog Tamar Dayan Charlotte Helfrich-Forster 《Proceedings. Biological sciences / The Royal Society》2013,280(1765)
Most studies in chronobiology focus on solar cycles (daily and annual). Moonlight and the lunar cycle received considerably less attention by chronobiologists. An exception are rhythms in intertidal species. Terrestrial ecologists long ago acknowledged the effects of moonlight on predation success, and consequently on predation risk, foraging behaviour and habitat use, while marine biologists have focused more on the behaviour and mainly on reproduction synchronization with relation to the Moon phase. Lately, several studies in different animal taxa addressed the role of moonlight in determining activity and studied the underlying mechanisms. In this paper, we review the ecological and behavioural evidence showing the effect of moonlight on activity, discuss the adaptive value of these changes, and describe possible mechanisms underlying this effect. We will also refer to other sources of night-time light (‘light pollution’) and highlight open questions that demand further studies. 相似文献
40.
Strategies to assess and optimize stability of endogenous amines during cerebrospinal fluid sampling
Marek J. Noga Ronald Zielman Robin M. van Dongen Sabine Bos Amy Harms Gisela M. Terwindt Arn M. J. M. van den Maagdenberg Thomas Hankemeier Michel D. Ferrari 《Metabolomics : Official journal of the Metabolomic Society》2018,14(4):44