2,051 research outputs found
Maternal undernutrition and the ovine acute phase response to vaccination
No full textBackground: The acute phase response is the immediate host response to infection, inflammation and trauma and can be monitored by measuring the acute phase proteins (APP) such as haptoglobin ( Hp) or serum amyloid A (SAA). The plane of nutrition during pregnancy is known to affect many mechanisms including the neuroendocrine and neuroimmune systems in neonatal animals but effects on the APP are unknown. To investigate this phenomenon the serum concentration of Hp and SAA was initially determined in non-stimulated lambs from 3 groups (n = 10/group). The dams of the lambs of the respective groups were fed 100% of requirements throughout gestation (High/High; HH); 100% of requirements for the first 65 d of gestation followed by 70% of requirements until 125 d from when they were fed 100% of requirements (High/Low; HL); 65% of liveweight maintenance requirements for the first 65 d gestation followed by 100% of requirements for the remainder of pregnancy ( Low/High; LH). The dynamic APP response in the lambs was estimated by measuring the concentration of Hp and SAA following routine vaccination with a multivalent clostridial vaccine with a Pasteurella component, Heptavac P (TM) following primary and secondary vaccination. Results: The Hp and SAA concentrations were significantly lower at the time of vaccination ( day 8-14) than on the day of birth. Vaccination stimulated the acute phase response in lambs with increases found in both Hp and SAA. Maternal undernutrition led to the SAA response to vaccination being significantly lower in the HL group than in the HH group. The LH group did not differ significantly from either the HH or HL groups. No significant effects of maternal undernutrition were found on the Hp concentrations. A significant reduction was found in all groups in the response of SAA following the second vaccination compared to the response after the primary vaccination but no change occurred in the Hp response. Conclusion: Decreased SAA concentrations, post-vaccination, in lambs born to ewes on the HL diet shows that maternal undernutrition prior to parturition affects the innate immune system of the offspring. The differences in response of Hp and SAA to primary and secondary vaccinations indicate that the cytokine driven APP response mechanisms vary with individual AP
Mutations in the Aeromonas salmonicida subsp. salmonicida type III secretion system affect Atlantic salmon leucocyte activation and downstream immune responses
No full textDeletion mutants of Aeromonas salmonicida subsp. salmonicida were used to determine the effect of the type three secretion system (TTSS) on Atlantic salmon anterior head kidney leucocytes (AHKL). One strain had a deletion in the outer membrane pore gene, ascC; and the other in three effector genes: aopO, aopH and aexT (we call this strain Δaop3). Host cell invasion success and 24h survival were depressed in ΔascC, as was 24h survival of Δaop3, when compared to the wild type strain. Challenge of AHKLs with A449 or TTSS mutants stimulated expression of the inflammatory mediators IL-8, IL-1 and TNFα at two bacterial concentrations (A600 0.1, 0.01). Expression of IL-12 was not stimulated in ΔascC challenged cells, whereas A449 and Δaop3 challenge resulted in an up-regulation of IL-12 in AHKLs, 2- and 4-fold higher than PBS, respectively. Only the wild type strain elicited a significant increase in IL-10 expression (5.5× at A600 0.1). Inducible nitric oxide synthetase (iNOS) and arginase (I+II) genes were also significantly up-regulated upon exposure to all strains. However, iNOS:arginase ratio was elevated in the effector mutant challenge. These results suggest that A. salmonicida subsp. salmonicida may enhance survival within the host cell through polarization of macrophages/leucocytes to an alternative, rather than classical, activation state. Furthermore, the short-term survival and lack of T-cell signalling cytokine stimulation in ΔascC, may help explain its inefficiency at providing protection to subsequent wild type challenge.ID: S1050464809002988; M3: Article; Accession Number: S1050464809002988; Author: Mark D. Fast (a, ∗); Author: Brenda Tse (b); Author: Jessica M. Boyd (c); Author: Stewart C. Johnson (d); Affiliation: School of Marine and Atmospheric Sciences, Stony Brook University, Stony Brook, New York 11794-5000, USA; Affiliation: Department of Biology, Dalhousie University, Halifax, Nova Scotia, Canada; Affiliation: Department of Microbiology and Immunology, Dalhousie University, Halifax, Nova Scotia, Canada; Affiliation: Pacific Biological Station, Fisheries and Oceans Canada, Nanaimo, British Columbia, Canada; Keyword: Aeromonas salmonicida; Keyword: Type three secretion system; Keyword: Atlantic salmon; Keyword: SHK-1; Keyword: Gene expression; Keyword: Inflammation; Keyword: Activation; Keyword: Interleukin-1β; Keyword: (IL-1β); Keyword: Interleukin-10; Keyword: Interleukin-12; Number of Pages: 8; Language: English;Source type: Electronic(1
Dissimilarity is used as evidence of category membership in multidimensional perceptual categorization: a test of the similarity-dissimilarity generalized context model
No full textIn exemplar models of categorization, the similarity between an exemplar and category members constitutes evidence that the exemplar belongs to the category. We test the possibility that the dissimilarity to members of competing categories also contributes to this evidence. Data were collected from two 2-dimensional perceptual categorization experiments, one with lines varying in orientation and length and the other with coloured patches varying in saturation and brightness. Model fits of the similarity-dissimilarity generalized context model were used to compare a model where only similarity was used with a model where both similarity and dissimilarity were used. For the majority of participants the similarity-dissimilarity model provided both a significantly better fit and better generalization, suggesting that people do also use dissimilarity as evidence
Cellular and hormonal disruption of fetal testis development in sheep reared on pasture treated with sewage sludge
No full textThe purpose of this study was to evaluate whether experimental exposure of pregnant sheep to a mixture of environmental chemicals added to pasture as sewage sludge (n = 9 treated animals) exerted effects on fetal testis development or function; application of sewage sludge was undertaken so as to maximize exposure of the ewes to its contents. Control ewes (n = 9) were reared on pasture treated with an equivalent amount of inorganic nitrogenous fertilizer. Treatment had no effect on body weight of ewes, but it reduced body weight by 12-15% in male (n = 12) and female (n = 8) fetuses on gestation day 110. In treated male fetuses (n = 11), testis weight was significantly reduced (32%), as were the numbers of Sertoli cells (34% reduction), Leydig cells (37% reduction), and gonocytes (44% reduction), compared with control fetuses (n = 8). Fetal blood levels of testosterone and inhibin A were also reduced (36% and 38%, respectively) in treated compared with control fetuses, whereas blood levels of luteinizing hormone and follicle-stimulating hormone were unchanged. Based on immunoexpression of anti-Müllerian hormone, cytochrome P450 side chain cleavage enzyme, and Leydig cell cytoplasmic volume, we conclude that the hormone changes in treated male fetuses probably result from the reduction in somatic cell numbers. This reduction could result from fetal growth restriction in male fetuses and/or from the lowered testosterone action; reduced immunoexpression of alpha-smooth muscle actin in peritubular cells and of androgen receptor in testes of treated animals supports the latter possibility. These findings indicate that exposure of the developing male sheep fetus to real-world mixtures of environmental chemicals can result in major attenuation of testicular development and hormonal function, which may have consequences in adulthood
Anthropogenic pollutants – an insidious threat to animal health and productivity?
No full textSummary Humans have always polluted their environment and, to an extent, the associated adverse consequences have increased in parallel with the global population. However, in recent decades, entirely novel compounds have been created, for multiple purposes, and some of these have become ubiquitous, damaging pollutants, which interfere with fundamental physiological processes in all animal species, disrupting reproductive and other functions. Understanding of the actions of these chemicals is poor but it is recognised that they can act additively, at low concentrations, and that animals at early stages of development are particularly sensitive to their effects. All species, including domestic and wild animals and humans, can be affected. Thus, there are potential adverse implications of exposure for farm and companion animal productivity and health, and associated economic implications. While anthropogenic pollutants exert subtle, but important, adverse effects on animal health and productivity, these should be weighed against the benefits associated with the use of these compounds, particularly in relation to food production and short-term determinants of animal health. However, it is suggested that it may be necessary to regulate future production and use of some of these compounds in order to ensure long term sustainability of production systems.</p
Introduction to physical oceanography
No full text"This textbook covers physical-oceanographic processes, theories, data, and measurements, targeted at upper-division undergraduates and graduate students in oceanography, meteorology, and ocean engineering. In addition to the classical topics, the author includes discussions of heat fluxes, the role of the ocean in climate, the deep circulation, equatorial processes including El Nino, databases used by oceanographers, the role of satellites and data from space, ship-based measurements, and the importance of vorticity in understanding oceanic flows. Students should have studied differential equations and introductory college physics, although math is de-emphasized."--Open Textbook Library.A voyage of discovery -- The historical setting -- The physical setting -- Atmospheric influences -- The oceanic heat budget -- Temperature, salinity, and density -- The equations of motion -- Equations of motion with viscosity -- Response of the upper ocean to winds -- Geostrophic currents -- Wind driven ocean circulation -- Vorticity in the ocean -- Deep circulation in the ocean -- Equatorial processes -- Numerical models -- Ocean waves -- Coastal processes and tides
Millisecond accuracy video display using OpenGL under Linux
No full textTo measure people’s reaction times to the nearest millisecond, it is necessary to know exactly when
a stimulus is displayed. This article describes how to display stimuli with millisecond accuracy on a
normal CRT monitor, using a PC running Linux. A simple C program is presented to illustrate how this
may be done within X Windows using the OpenGL rendering system. A test of this system is reported
that demonstrates that stimuli may be consistently displayed with millisecond accuracy. An algorithm
is presented that allows the exact time of stimulus presentation to be deduced, even if there are relatively
large errors in measuring the display time
Sunitinib treatment exacerbates intratumoral heterogeneity in metastatic renal cancer
No full textThis work was supported by the Chief Scientist Office, Scotland (ETM37; to G.D. Stewart, A.C.P. Riddick, M. Aitchison, and D.J. Harrison), Cancer Research UK (Experimental Cancer Medicine Centre; to T. Powles, London and D.J. Harrison, Edinburgh), Medical Research Council (to A. Laird and D.J. Harrison), Royal College of Surgeons of Edinburgh (to A. Laird), Melville Trust (to A. Laird), Medical Research Council (MC_UU_12018/25; to I.M. Overton), Royal Society of Edinburgh Scottish Government Fellowship cofunded by Marie Curie Actions (to I.M. Overton), Renal Cancer Research Fund (to G.D. Stewart), Kidney Cancer Scotland (to G.D. Stewart) and an educational grant from Pfizer (to T. Powles).Purpose: The aim of this study was to investigate the effect of VEGF targeted therapy (sunitinib) on molecular intratumoral heterogeneity (ITH) in metastatic clear cell renal cancer (mccRCC). Experimental design: Multiple tumor samples (n=187 samples) were taken from the primary renal tumors of mccRCC patients who were sunitinib treated (n=23, SuMR clinical trial) or untreated (n=23, SCOTRRCC study). ITH of pathological grade, DNA (aCGH), mRNA (Illumina Beadarray) and candidate proteins (reverse phase protein array) were evaluated using unsupervised and supervised analyses (driver mutations, hypoxia and stromal related genes). ITH was analysed using intratumoral protein variance distributions and distribution of individual patient aCGH and gene expression clustering. Results: Tumor grade heterogeneity was greater in treated compared to untreated tumors (P=0.002). In unsupervised analysis, sunitinib therapy was not associated with increased ITH in DNA or mRNA. However, there was an increase in ITH for the driver mutation gene signature (DNA and mRNA) as well as increasing variability of protein expression with treatment (p<0.05). Despite this variability, significant chromosomal and transcript changes to key targets of sunitinib, such as VHL, PBRM1 and CAIX, occurred in the treated samples. Conclusions: These findings suggest that sunitinib treatment has significant effects on the expression and ITH of key tumor and treatment specific genes/proteins in mccRCC. The results, based on primary tumor analysis, do not support the hypothesis that resistant clones are selected and predominate following targeted therapy.Peer reviewe
Martha Stewart: Was Justice Served
No full textFrom decorating diva to corporate criminal, Martha Stewart is one of many individuals to receive criminal penalty for corporate crime. Substantial increases in the number of corporate crime cases being pursued over the last few decades has lead to increased popular awareness of these issues. Charles Alexander, author of Time Magazine's article Crimes of the Suite, agrees in stating "the way things are going, Fortune may soon have to publish a 500 Most Wanted list" (Alexander, 1985).
Alexander goes on further to say that "[m]any whitecollar criminals are first-time offenders who have records of contributions to their community and have often led exemplary lives"(Alexander, 1985). This unique profile creates a mixed opinion of the correct punishment for "crimes of the suite."
The unprecedented media attention and speculation led the IMClone Scandal to be more commonly referred to as the Martha Stewart Scandal. Despite her minor personal (not corporate) involvement, the small amount of money involved and the weak evidence against her media attention suggests that Stewart was targeted as a main member of the IMClone scandal because of her celebrity status (CBS, 2003). The purpose of this thesis is to assess the accuracy of this wide spread speculation.
The research conducted compared ten other corporate crime cases with the case of Martha Stewart using both qualitative and quantitative measures. Results support speculation that Stewart received a harsher sentence than normal. The trial encountered bias due to Stewart's recognition as a high profile corporate figurehead confirming that martyrs do exist within the prosecution of corporate crime
STM imaging of the complete bacterial cell sheath of Methanospirillum hungatei
No full textPT: J; CR: BLACKFORD BL, 1987, REV SCI INSTRUM, V58, P1343 DAHN DC, 1988, J VAC SCI TECHNOL A, V6, P548 SPROTT GD, 1986, CAN J MICROBIOL, V32, P847 STEWART M, 1985, J MOL BIOL, V183, P509; NR: 4; TC: 16; J9: J MICROSC-OXFORD; PN: Part 1; PG: 7; GA: T9506Source type: Electronic(1
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