2,216 research outputs found
Duration of antibody response following vaccination against feline immunodeficiency virus
Objectives:
Recently, two point-of-care (PoC) feline immunodeficiency virus (FIV) antibody test kits (Witness and Anigen Rapid) were reported as being able to differentiate FIV-vaccinated from FIV-infected cats at a single time point, irrespective of the gap between testing and last vaccination (0–7 years). The aim of the current study was to investigate systematically anti-FIV antibody production over time in response to the recommended primary FIV vaccination series.
Methods:
First, residual plasma from the original study was tested using a laboratory-based ELISA to determine whether negative results with PoC testing were due to reduced as opposed to absent antibodies to gp40. Second, a prospective study was performed using immunologically naive client-owned kittens and cats given a primary FIV vaccination series using a commercially available inactivated whole cell/inactivated whole virus vaccine (Fel-O-Vax FIV, three subcutaneous injections at 4 week intervals) and tested systematically (up to 11 times) over 6 months, using four commercially available PoC FIV antibody kits (SNAP FIV/FeLV Combo [detects antibodies to p15/p24], Witness FeLV/FIV [gp40], Anigen Rapid FIV/FeLV [p24/gp40] and VetScan FeLV/FIV Rapid [p24]).
Results:
The laboratory-based ELISA showed cats from the original study vaccinated within the previous 0–15 months had detectable levels of antibodies to gp40, despite testing negative with two kits that use gp40 as a capture antigen (Witness and Anigen Rapid kits). The prospective study showed that antibody testing with SNAP Combo and VetScan Rapid was positive in all cats 2 weeks after the second primary FIV vaccination, and remained positive for the duration of the study (12/12 and 10/12 cats positive, respectively). Antibody testing with Witness and Anigen Rapid was also positive in a high proportion of cats 2 weeks after the second primary FIV vaccination (8/12 and 7/12, respectively), but antibody levels declined below the level of detection in most cats (10/12) by 1 month after the third (final) primary FIV vaccination. All cats tested negative using Witness and Anigen Rapid 6 months after the third primary FIV vaccination.
Conclusions and relevance:
This study has shown that a primary course of FIV vaccination does not interfere with FIV antibody testing in cats using Witness and Anigen Rapid, provided primary vaccination has not occurred within the previous 6 months. Consequently, Witness and Anigen Rapid antibody test kits can be used reliably to determine FIV infection status at the time of annual booster FIV vaccination to help detect ‘vaccine breakthroughs’ and in cats that have not received a primary course of FIV vaccination within the preceding 6 months. The duration of antibody response following annual booster FIV vaccination and the resulting effect on antibody testing using PoC kits needs to be determined by further research. The mechanism(s) for the variation in FIV antibody test kit performance remains unclear
Leaf-Tip Morphology Does Not Support Species Status for the Seagrass Halodule beaudettei in Florida, USA
Anti-Inflammatory Activity of (Polyphenolic)-Sulfonates and Their Sodium Salts in Rodents
A series of polyphenolic-sulfonated compounds were observed to have potent anti-inflammatory activity
and were protective against induced endotoxic shock in mice at 8 and 16 mg/kg, I.P. These agents proved
to be potent elastase inhibitors in human leukocytes and J774-AI and IC-21 mouse macrophages as well as
prostaglandin cyclo-oxygenase inhibitors in J774-AI macrophages. The compounds from 5 to 50 μM
inhibited TNFα release from IC-21 macrophages and IL-1 release from mouse P388D1 macrophages
induced by LPS. The binding of these cytokines to high affinity receptors on target cells, e.g. L929
fibroblasts and IL-2 in HuT78 T lymphoma cells, were also suppressed by the agents. These compounds
blocked the adhesion of leukocytes and macrophages to the plasma membranes of L929 fibroblasts
From Isotopes to TK Interviews: Towards Interdisciplinary Research in Fort Resolution and the Slave River Delta, Northwest Territories
Evolving research in Fort Resolution and the Slave River Delta, Northwest Territories, aims to improve understanding of how the natural ecosystem functions and responds to various environmental stressors, as well as to enhance the stewardship of natural resources and the capacity of local residents to respond to change. We seek to integrate approaches that span the natural and social sciences and traditional knowledge understandings of change, employing a research design developed in response to the concerns of a northern community. In doing so, we have strived for a research process that is collaborative, interdisciplinary, policy-oriented, and reflective of northern priorities. These elements characterize the new northern research paradigm increasingly promoted by various federal funding agencies, northern partners, and communities. They represent a holistic perspective in the pursuit of solutions to address complex environmental and socioeconomic concerns about impacts of climate change and resource development on northern societies. However, efforts to fulfill the objectives of this research paradigm are associated with a host of on-the-ground challenges. These challenges include (but are not restricted to) developing effective community partnerships and collaboration and documenting change through interdisciplinary approaches. Here we provide an overview of the components that comprise our interdisciplinary research program and offer an accounting of our formative experiences in confronting these challenges
Development of an Evidence-Based Compendium of Institutional Graduate Medical Education Leadership Competencies (GMELCs)
Treatment patterns for cancer in Western Australia: does being Indigenous make a difference?
Objective: To examine whether hospital patients with cancer who were identified as Indigenous were as likely to receive surgery for the cancer as non-Indigenous patients. Design, setting and patients: Epidemiological survey of all Western Australian (WA) patients who had a cancer registration in the state-based WA Record Linkage Project that mentioned cancer of the breast (1982–2000) or cancer of the lung or prostate (1982–2001).
Main outcome measures: The likelihoods of receiving breast-conserving surgery or mastectomy for breast cancer, lung surgery for lung cancer, or radical or non-radical prostatectomy for prostate cancer were compared between the Indigenous and non-Indigenous populations using adjusted logistic regression analyses.
Results: Indigenous people were less likely to receive surgery for their lung cancer (odds ratio [OR], 0.64; 95% CI, 0.41–0.98). Indigenous men were as likely as non- Indigenous men to receive non-radical prostatectomy (OR, 0.69; 95% CI, 0.40–1.17); only one Indigenous man out of 64 received radical prostatectomy. Indigenous women were as likely as non-Indigenous women to undergo breast-conserving surgery (OR, 0.86; 95% CI, 0.60–1.21).
Conclusions: These results indicate a different pattern of surgical care for Indigenous patients in relation to lung and prostate, but not breast, cancer. Reasons for these disparities, such as treatment choice and barriers to care, require further investigation
The Effects of Amine-Carboxyborane Related Derivatives on UMR-106 Bone Metabolism
The amine-carboxyboranes and related derivatives have been shown to be
potent anti-inflammatory and anti-osteoporosis agents. Their action in
part appears to be mediated by the modulation of cytokines, e.g. TNFα
or IL-1. Previous studies have demonstrated that LPS induced
macrophages release of TNFα maximally at 60 to 90 min. and IL-1 from 5
to 8 hr. The amine-carboxyboranes reduced significantly the release of
these cytokines but also blocked TNFα high affinity binding to UMR-106
receptor at 90 min. at 10 μM, and IL-1 high affinity binding at 5 hr. at
12.5 μM. In addition, the agents suppressed IL-8 binding to CHO K1 high
affinity receptor at 24 hr. at 50 μM and IL-2 binding to HuT-8 receptors
at 25 μM at 90 min. and 5 hr. Correlation of metabolic events
associated with osteoporosis showed that at 90 min., when TNFα receptor
binding was reduced by the agents, calcium uptake into UMR-106 cells was
reduced at 10 μM as well as the acid and alkaline phosphatases, and the
prostaglandin cyclo-oxygenase activities and adhesion of leukocytes and
macrophages to UMR-106 cell monolayers. At 5hr. when the agents reduced
IL-1 binding to UMR-106 receptors, calcitonin and 1,25-dihydrovitamin D3
binding was reduced by the agents as was acid and alkaline phosphatase,
and 5′-lipoxygenase activities and white blood cell adhesion. At this
time calcium uptake and proline incorporation was increased
significantly by the agents. At later times e.g. 18-48 hr. calcium
uptake was still increased, and NAG activity was inhibited in the
presence of the agents. These effects may be related more to the
inhibition of other cytokine receptor binding, e.g. IL-8. Thus, many of
the observed metabolic effects of amine-carboxyboranes as antiosteoporosis
agents can be correlated with their inhibition of cytokine
high affinity binding to target cell receptors
The Arp2/3 complex is essential for the actin-based motility of Listeria monocytogenes
AbstractActin polymerisation is thought to drive the movement of eukaryotic cells and some intracellular pathogens such as Listeria monocytogenes. The Listeria surface protein ActA synergises with recruited host proteins to induce actin polymerisation, propelling the bacterium through the host cytoplasm [1]. The Arp2/3 complex is one recruited host factor [2,3]; it is also believed to regulate actin dynamics in lamellipodia [4,5]. The Arp2/3 complex promotes actin filament nucleation in vitro, which is further enhanced by ActA [6,7]. The Arp2/3 complex also interacts with members of the Wiskott–Aldrich syndrome protein (WASP) [8] family – Scar1 [9,10] and WASP itself [11]. We interfered with the targeting of the Arp2/3 complex to Listeria by using carboxy-terminal fragments of Scar1 that bind the Arp2/3 complex [11]. These fragments completely blocked actin tail formation and motility of Listeria, both in mouse brain extract and in Ptk2 cells overexpressing Scar1 constructs. In both systems, Listeria could initiate actin cloud formation, but tail formation was blocked. Full motility in vitro was restored by adding purified Arp2/3 complex. We conclude that the Arp2/3 complex is a host-cell factor essential for the actin-based motility of L. monocytogenes, suggesting that it plays a pivotal role in regulating the actin cytoskeleton
Plucking enhanced beneath ice sheet margins: evidence from the Grampian Mountains, Scotland
Concentrations of boulders are a common feature of landscapes modified by former mid-latitude ice sheets. In many cases, the origin of the boulders can be traced in the up-ice direction to a cliff only tens to hundreds of metres distant. The implication is that a pulse of plucking and short boulder transport occurred beneath thin ice at the end of the last glacial cycle. Here we use a case study in granite bedrock in the Dee Valley, Scotland, to constrain theory and explore the factors involved in such a late phase of plucking. Plucking is influenced by ice velocity, hydrology, effective ice pressure, the extent of subglacial cavities and bedrock characteristics. The balance between these factors favours block removal beneath thin ice near a glacier margin. At Ripe Hill in the Dee Valley, a mean exposure age of 14.2 ka on blocks supports the view that the boulder train formed at the end of ice sheet glaciation. The late pulse of plucking was further enhanced by ice flowing obliquely across vertical joints and by fluctuations in sub-marginal meltwater conditions. An implication of the study is that there is the potential for a wave of ice-marginal plucking to sweep across a landscape as an ice sheet retreats
- …