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Fukuoka Y Xia HZ Sanchez-Muñoz LB Dellinger AL Escribano L Schwartz LB 《Journal of immunology (Baltimore, Md. : 1950)》2008,180(9):6307-6316
Both mast cells and complement participate in innate and acquired immunity. The current study examines whether beta-tryptase, the major protease of human mast cells, can directly generate bioactive complement anaphylatoxins. Important variables included pH, monomeric vs tetrameric forms of beta-tryptase, and the beta-tryptase-activating polyanion. The B12 mAb was used to stabilize beta-tryptase in its monomeric form. C3a and C4a were best generated from C3 and C4, respectively, by monomeric beta-tryptase in the presence of low molecular weight dextran sulfate or heparin at acidic pH. High molecular weight polyanions increased degradation of these anaphylatoxins. C5a was optimally generated from C5 at acidic pH by beta-tryptase monomers in the presence of high molecular weight dextran sulfate and heparin polyanions, but also was produced by beta-tryptase tetramers under these conditions. Mass spectrometry verified that the molecular mass of each anaphylatoxin was correct. Both beta-tryptase-generated C5a and C3a (but not C4a) were potent activators of human skin mast cells. These complement anaphylatoxins also could be generated by beta-tryptase in releasates of activated skin mast cells. Of further biologic interest, beta-tryptase also generated C3a from C3 in human plasma at acidic pH. These results suggest beta-tryptase might generate complement anaphylatoxins in vivo at sites of inflammation, such as the airway of active asthma patients where the pH is acidic and where elevated levels of beta-tryptase and complement anaphylatoxins are detected. 相似文献
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The Inter-Tribal Fisheries and Assessment Program (ITFAP) of the Chippewa Ottawa Resource Authority (CORA) in Sault Ste. Marie, Michigan, has been monitoring contaminant concentrations in the fillet portions of lake trout (Salvelinus namaycush) and lake whitefish (Coregonus clupeaformis) from the waters of lakes Superior, Huron, and Michigan since 1991. The primary purpose of this article is to present a risk quantification of methylmercury (MeHg) that is adjusted for nutritional benefit, originally presented by Ginsberg and Toal (2009, 2015) on trends in contaminant concentrations in fillet portions of these commercial fish that we recently reported in Dellinger et al. (2014). Both species of fish caught by tribal fishermen showed clear benefits to cardiovascular health and infant neurodevelopment if consumed at a rate of six ounces per week. However, other popularly consumed fish such as cod, tuna, and tilapia are estimated to have only marginal benefit or net negative effects on cardiovascular health and infant neurodevelopment. This dynamic assessment of benefits and risks further demonstrates the importance of traditionally caught fish in tribal health. 相似文献
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Valente AL Delgado C Moreira C Ferreira S Dellinger T Pinheiro de Carvalho MA Costa G 《The Journal of parasitology》2009,95(1):249-252
The helminth fauna of pelagic-stage loggerhead sea turtles, Caretta caretta, is still poorly known. Here, we describe the helminth-component community of healthy, free-ranging juvenile loggerhead sea turtles captured in the waters around Madeira Island, Portugal. Fifty-seven were used in this study. The esophagus, stomach, intestine, liver, gallbladder, spleen, kidneys, trachea, bronchi, urinary bladder, heart, left and right aortas, and coelomic cavity were macroscopically inspected; organs and tissues were removed and washed through a sieve. A search for parasites was made using a stereoscopic microscope; recovered parasites were fixed and stored in 70% alcohol until staining and identification. Prevalence, mean intensity, and mean abundance values were recorded. In total, 156 parasite specimens belonging to 9 species were found: nematodes included Anisakis simplex s.l. (larvae) and an unidentified species; digenetic trematodes present were Enodiotrema megachondrus, Rhytidodes gelatinosus, Pyelosomum renicapite, and Calycodes anthos; acanthocephalans included Bolbosoma vasculosum and Rhadinorhynchus pristis; a single cestode, Nybelinia sp., was present. Parasite infections were found to have both low prevalences and intensities. Possible reasons for this include the oligotrophic conditions of the pelagic habitat around Madeira; a 'dilution effect' because of the vastness of the area; and the small size, and thus ingestion rate, of the turtles. Results are discussed in terms of the various turtle populations that may use the waters surrounding Madeira. This work provides valuable information on the parasite fauna of a poorly known stage in the life of loggerhead sea turtles, thereby filling a fundamental gap with regard to features of the parasite fauna in this species. 相似文献
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G N La Mar C M Dellinger S S Sankar 《Biochemical and biophysical research communications》1985,128(2):628-633
The 57Fe chemical shift of sperm whale carbonyl myoglobin and two model complexes have been determined by double resonance methods in doubly enriched [57Fe, 13C] samples. Deprotonation of the axial imidazole in the model complex causes a large upfield 57Fe chemical shift, consistent with the increased ligand field strength. The 57Fe signal for MbCO is to low field of that of the neutral imidazole complex, arguing against significant hydrogen-bonding of its imidazole but supporting a slight axial strain. This indirect method permits the first effective study of 57Fe shifts in a limited class of hemoproteins. 相似文献
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A matter of scale: apparent niche differentiation of diploid and tetraploid plants may depend on extent and grain of analysis
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Bernhard Kirchheimer Christoph C. F. Schinkel Agnes S. Dellinger Simone Klatt Dietmar Moser Manuela Winkler Jonathan Lenoir Marco Caccianiga Antoine Guisan Diego Nieto‐Lugilde Jens‐Christian Svenning Wilfried Thuiller Pascal Vittoz Wolfgang Willner Niklaus E. Zimmermann Elvira Hrandl Stefan Dullinger 《Journal of Biogeography》2016,43(4):716-726
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Stage VI Xenopus oocytes are suspended at the G2/M transition of meiosis I, and represent an excellent system for the identification and examination of cell cycle regulatory proteins. Essential cell cycle regulators such as MAPK, cyclins and mos have the ability to induce oocyte maturation, causing the resumption of the cell cycle from its arrested state. We have identified the product of a novel Xenopus gene, Speedy or Spy1, which is able to induce rapid maturation of Xenopus oocytes, resulting in the induction of germinal vesicle breakdown (GVBD) and activation of M-phasepromoting factor (MPF). Spy1 activates the MAPK pathway in oocytes, and its ability to induce maturation is dependent upon this pathway. Spy1-induced maturation occurs much more rapidly than maturation induced by other cell cycle regulators including progesterone, mos or Ras, and does not require any of these proteins or hormones, indicating that Spy1-induced maturation proceeds through a novel regulatory pathway. In addition, we have shown that Spy1 physically interacts with cdk2, and prematurely activates cdk2 kinase activity. Spy1 therefore represents a novel cell cycle regulatory protein, inducing maturation through the activation of MAPK and MPF, and also leading to the premature activation of cdk2. 相似文献
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Øystein H. Opedal Rocío Pérez-Barrales Vinícius L. G. Brito Nathan Muchhala Miquel Capó Agnes Dellinger 《American journal of botany》2023,110(6):e16200
Pollen plays a key role in plant reproductive biology. Despite the long history of research on pollen and pollination, recent advances in pollen-tracking methods and statistical approaches to linking plant phenotype, pollination performance, and reproductive fitness yield a steady flow of exciting new insights. In this introduction to the Special Issue “Pollen as the Link Between Phenotype and Fitness,” we start by describing a general conceptual model linking functional classes of floral phenotypic traits to pollination-related performance metrics and reproductive fitness. We use this model as a framework for synthesizing the relevant literature, highlighting the studies included in the Special Issue, and identifying gaps in our understanding and opportunities for further development of the field. The papers that follow in this Special Issue provide new insights into the relationships between pollen production, presentation, flower morphology, and pollination performance (e.g., pollen deposition onto stigmas), the role of pollinators in pollen transfer, and the consequences of heterospecific pollen deposition. Several of the studies demonstrate exciting experimental and analytical approaches that should pave the way for continued work addressing the intriguing role of pollen in linking plant phenotypes to reproductive fitness. 相似文献