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H. This (h + this)
Selected AbstractsThermoluminescence sensitivity and thermal history of type 3 ordinary chondrites: Eleven new type 3.0,3.1 chondrites and possible explanations for differences among H, L, and LL chondritesMETEORITICS & PLANETARY SCIENCE, Issue 6 2002P. H. Benoit We have identified 11 UOCs of petrologic types 3.0,3.1: Adrar 003, Elephant Moraine (EET) 90066, EET 90161, Grosvenor Mountains (GRO) 95502, Lewis Cliff (LEW) 88477, Meteorite Hills (MET) 96503, Yamato (Y)-790787, Y-791324, Y-791558, Y-793565, and Y-793596. These samples represent an important new resource for researchers interested in the nature of primitive solar system materials. Previously reported trends in which TL sensitivity increases with TL peak temperature and TL peak width, which we interpret in terms of crystallization of feldspar in the ordered or disordered forms during metamorphism, are confirmed by the new data. Importantly, the present data strengthen the trend described earlier in which the mean level of metamorphism experienced by UOCs increases along the series LL, L and H. This suggests either different burial depths for the UOCs from each class, or formation at similar depths in regoliths of different thickness. [source] Infectious gastroenteritis caused by Vibrio harveyi (V. carchariae) in cultured red drum, Sciaenops ocellatusJOURNAL OF APPLIED ICHTHYOLOGY, Issue 1 2003P.-C. Liu Summary An outbreak of serious mortality among the cultured red drum Sciaenops ocellatus (L.) characterized by a swollen intestine containing transparent yellow fluid (ascites and gastroenteritis) occurred in July 2000 in Taiwan. A motile strain Rd 0700 was isolated from head kidney and/or the intestinal yellow fluid on tryptone soya agar (TSA) supplemented with 2% (w/v) NaCl and/or thiosulfate citrate bile salt (TCBS) sucrose agar plates. Applying biochemical characteristics, this strain was characterized and identified as Vibrio harveyi (V. carchariae). The bacteria could be re-isolated from kidney, liver, and the transparent yellow fluid of swollen intestine of fish after bacterial challenge. The LD50 values of the organism and its extracellular products (ECP) were 2.9×107 colony forming units (CFU) and 3.85 ,g protein g,1 fish body weight, respectively. All moribund/dead fish exhibited gastroenteritis except those killed within 12 h. This is a first report showing that intraperitoneal (i.p.) injection of the ECP from V. carchariae is lethal to red drum and can reproduce gastroenteritis in the fish. [source] Oxidative stress increases levels of endogenous amyloid-, peptides secreted from primary chick brain neuronsAGING CELL, Issue 5 2008Claire Goldsbury Summary Oxidative damage is associated with Alzheimer's disease and mild cognitive impairment, but its relationship to the development of neuropathological lesions involving accumulation of amyloid-, (A,) peptides and hyperphosphorylated tau protein remains poorly understood. We show that inducing oxidative stress in primary chick brain neurons by exposure to sublethal doses of H2O2 increases levels of total secreted endogenous A, by 2.4-fold after 20 h. This occurs in the absence of changes to intracellular amyloid precursor protein or tau protein levels, while heat-shock protein 90 is elevated 2.5-fold. These results are consistent with the hypothesis that aging-associated oxidative stress contributes to increasing A, generation and up-regulation of molecular chaperones in Alzheimer's disease. [source] Characterization of sirolimus metabolites in pediatric solid organ transplant recipientsPEDIATRIC TRANSPLANTATION, Issue 1 2009Guido Filler Abstract:, Potential age-dependent changes of sirolimus metabolite patterns in pediatric renal transplant recipients remain elusive. Thirteen pediatric solid organ transplant recipients (10 kidney, one combined liver,kidney, two liver, mean age 8.0 ± 5.0 yr) underwent a sirolimus pharmacokinetic profile in steady-state with 10 samples drawn over 12 h post-intake to calculate the AUC0,12 h. Concentrations of sirolimus and metabolite were quantified using a validated LC-MS/MS assay and metabolite structures were identified directly in blood extracts using LC-MS/iontrap. Average sirolimus AUC0,12 h was 64.9 ± 29.7 ng h/mL. Median (range) AUC0,12 h for each metabolite (ng h/mL) was: 12-hydroxy-sirolimus 7.6 (0.2,18.8), 46-hydroxy sirolimus 3.1 (0.0,12.4), 24-hydroxy sirolimus 4.3 (0.0,12.6), piperidine-hydroxy sirolimus 3.5 (0.0,8.3), 39- O -desmethyl sirolimus 3.6 (0.0,11.3), 16- O -desmethyl sirolimus 5.0 (0.1,9.9), and di-hydroxy sirolimus 4.3 (0.0,32.5). The metabolites reached a median total AUC0,12 h of 60% of that of sirolimus. The range was 2.6,136%, indicating significant variability. In all, 77.5% of the metabolites were hydroxylated, while 39- O -desmethyl sirolimus accounted for only 8.4% of the AUC0,12 h. This is clinically relevant as 39- O -desmethyl sirolimus shows 86,127% cross-reactivity with the antibody of the widely used Abbott sirolimus immunoassay. The metabolism of sirolimus in the children included in our study differed from that reported in adults, which should be considered when monitoring sirolimus exposure immunologically. [source] Screening and isolation of a nematicidal sesquiterpene from Magnolia grandiflora L.PEST MANAGEMENT SCIENCE (FORMERLY: PESTICIDE SCIENCE), Issue 3 2007Linjun Hong Abstract The ethanolic extracts from 30 plant species were tested for their nematicidal activity against nematodes Bursaphelenchus xylophilus (Steiner & Buhrer) Nickle and Panagrellus redivivus (L.) Goodey. The leaf extract of Magnolia grandiflora L. exhibited the strongest nematicidal activity against both nematodes, causing 73 and 100% mortality respectively within 48 h at 5 mg mL,1. A new nematicidal sesquiterpene was obtained from the leaves of M. grandiflora. The compound was determined to be 4,5-epoxy-1(10)E,11(13)-germacradien-12,6-olide, based on spectroscopic methods including 2D NMR techniques. The median lethal concentrations (LC50) of the compound against B. xylophilus and P. redivivus were 71 and 46 mg L,1 respectively at 48 h. This is the first report of Magnoliaceae species with nematicidal activity. Copyright © 2007 Society of Chemical Industry [source] Transforming growth factor-,1 and ultraviolet A1 radiation increase production of vascular endothelial growth factor but not endothelin-1 in human dermal fibroblastsBRITISH JOURNAL OF DERMATOLOGY, Issue 3 2000S. Trompezinski Background ,Normal and dysregulated wound healing involves fibroblast activation and angiogenesis, in which polypeptide factors such as transforming growth factor (TGF)-,, vascular endothelial growth factor (VEGF) and endothelin-1 (ET-1) play an important part. Ultraviolet (UV) A1 (365 nm) has recently received attention as a possible treatment for some dermal fibrotic disorders. Objectives,The aim of this study was to evaluate the effects of TGF-,1 and UVA1 radiation, as well as that of cobalt chloride, reported to mimic hypoxia both in vivo and in vitro, on the expression of VEGF and ET-1 by cultured human dermal fibroblasts. Methods,Levels of VEGF and ET-1 were measured by enzyme-linked immunosorbent assay and expression of neutral endopeptidase (NEP, CD10), known to degrade ET-1, was quantified by flow cytometric analysis after cell trypsinization. Results,Our results showed that the cells released minor amounts of VEGF and ET-1. Both TGF-,1 and UVA1 strongly increased VEGF secretion in a dose- and time-dependent manner, without significantly affecting ET-1 release. Irradiation of TGF-,1-stimulated fibroblasts resulted in a synergistic effect on increasing levels of VEGF but not ET-1 after 48 h. Cobalt chloride stimulated the secretion of VEGF by fibroblasts; the effects of TGF-,1 and cobalt were additive. However, no significant effect of cobalt chloride on ET-1 secretion was observed, suggesting that ET-1 production in fibroblasts is not oxygen-sensitive. The expression of NEP was not modified by TGF-,1 or UVA1 radiation. Addition of a neutralizing anti-CD10 antibody to fibroblast cultures downregulated CD10 expression at the cell surface without changing ET-1 levels in cell supernatants after 24 or 48 h. This suggests that membrane-bound NEP has minimal or no activity against secreted ET-1. Conclusions,Taken together, these results underline the major role played by TGF-,1 in increasing VEGF secretion by fibroblasts. This, as well as the documented effect of UVA1 on increasing VEGF production, may have implications for wound healing in vivo. [source] Macrophage inflammatory protein-1, and C,C chemokine receptor-1 in allergen-induced skin late-phase reactions: relationship to macrophages, neutrophils, basophils, eosinophils and T lymphocytesCLINICAL & EXPERIMENTAL ALLERGY, Issue 11 2001S. Ying Background Macrophage inflammatory protein (MIP)-1, binds to C,C chemokine receptor (CCR)-1 with high affinity. CCR-1 is expressed on neutrophils, eosinophils, monocytes, T lymphocytes and basophils; cells characteristic of atopic allergic inflammation. In vitro, MIP-1, is chemotactic for monocytes, T cells and basophils and is also a potent histamine-releasing factor for basophils and mast cells. Although increased levels of MIP-1, were shown in atopic allergic disorders, the kinetics of expression of these CC chemokines in vivo is largely unknown. Objective To investigate the kinetics of expression of MIP-1, and receptor CCR-1 and the relationships between the expression and infiltration of inflammatory cells in allergen-induced cutaneous late-phase reactions in atopic subjects. Methods Cryostat sections, obtained from skin biopsies from 10 human atopic subjects at 6, 24, 48, 72 h and 7 days after allergen challenge, were processed for immunohistochemistry and in situ hybridization using 35S-labelled riboprobes. Results The peak expression of allergen-induced mRNA for MIP-1, and CCR-1 was 6 h. This was maintained at 24 h, and gradually returned to base line at 7 days. At 6 h, the number of cells expressing MIP-1, mRNA significantly correlated with elastase+ neutrophils and BB-1+ basophils. At 24 h, the MIP-1, mRNA+ cells significantly correlated with CD68+ macrophages. There were significant inverse correlations between the numbers of MIP-1, mRNA cells and the numbers of Tryptase+ mast cells at 6 and 24 h after allergen challenge. Conclusion Allergen-induced cutaneous late-phase reactions in humans were associated with increased expression of MIP-1, and CCR-1. This may be relevant to the infiltration of neutrophils, eosinophils, basophils and macrophages. [source] | ||||||||||