236 research outputs found
Western Boundary Current-Subtropical Continental Shelf Interactions
No full textWestern boundary currents (WBCs) adjacent to subtropical continental shelves (STCSs; between ~25° and 35° latitude; Figure 1) transport heat, nutrients, and biota poleward along the western margins of major ocean basins, interacting with the continental margins and influencing their physics and biology. Eddies and meanders along the shelf edge upwell deep, nutrient-laden water that can be advected onto the adjacent shelves with a corresponding export of particle-rich shelf water (e.g., Lee et al., 1991; Kimura et al., 1997; Campos et al., 2000; Roughan and Middleton, 2002, 2004; Lutjeharms, 2006; Savidge and Savidge, 2014). Despite their similarities, the various STCS regions display key differences with respect to boundary current strength and variability, shelf width and geometry, and trophic structure. Comparative analyses of the physical forcing and biological responses among STCS have the potential to reveal common underlying properties, forcing mechanisms, and sensitivities to climatic perturbations that are not possible to elucidate with region-specific studies. This kind of fundamental understanding of relationships between physics and biological responses is critical to predicting consequences of environmental change across a wide range of spatiotemporal scales
T cell priming in murine mycobacterial infection and disease.
No full textMycobacterium tuberculosis (Mtb) continues to pose a major health risk across the globe. Attempts to control the spread of the disease have been hampered by the lack of a vaccine that can protect against pulmonary tuberculosis (TB). Due to the nature of Mtb as an intracellular obligate human pathogen, it has a very complex relationship with the human immune system. To overcome TB, we must gain a better understanding of the immune system, how it interacts with Mtb and how it can be manipulated to generate a more protective immune response. Due to the intracellular nature of Mtb, research is focused on driving a T cell response to activate macrophages and thereby reduce infection. It has been shown that early priming conditions alter the downstream T cell phenotype. We have found this is true in the context of Mtb and priming T cells with a suboptimal epitope impacts the phenotype of antigen-specific T cells during the progression of infection in the lung and is associated with the expression of immunity. We do not fully understand the nature of this change and its wider effects that provide a more protective phenotype, but it highlights the power of TCR:Antigen:MHC priming interactions as a tool for vaccination research. We also addressed the importance of the environment on T cell function in the infected lung. The TB lesion is a complex, inhibitory environment and we chose to reduce one known inhibitory agent, nitric oxide and found this altered the phenotype of lung resident T cells and allowed them to become more differentiated. This increased differentiation was associated with increased expression of the protective cytokine IFN-γ and reduced bacterial burden. These data support the opportunity for focused therapeutic interventions that allow the immune response to function optimally. Overall, our work demonstrates that the T cell response to Mtb can be manipulated both at initiation and expression of function.</p
Confocal analysis of fluorescent bead uptake by mouse Peyer's patch follicle-associated M cells
No full textLatex beads coated with secretory immunoglobulin (IgA) instilled into mouse intestinal loops are taken up by M cells present in Peyer's patch follicle-associated epithelial tissue. Bead adsorption and uptake is greater at the edge compared with the apex of follicle domes. Coating beads with bovine serum albumin (BSA) causes a fourfold reduction in adsorption and a twentyfold reduction in uptake. Results demonstrate selectivity between adsorption and uptake and between the ability of different proteins to facilitate uptake
Zinc toxicosis - associated hemolytic anemia and pancreatic disease in 2 dogs [In Press]
No full textPollination and breeding biology of Large-flowered Bellwort, Uvularia grandiflora
No full textVolume: 105Start Page: 392End Page: 39
Glial Orchestrated Neurodegeneration: An Important Crossroad for Neural Stem Cell Therapy to the Intestine
No full text
Serologic and urinary survey of exposure to Leptospira species in a feral cat population of Prince Edward Island, Canada [online first]
No full textObjectives
Recent studies show that cats could play an important role in the transmission of Leptospira species. There are few reports of leptospirosis on Prince Edward Island (PEI) and none in cats. The objective of this study was to determine the prevalence of serum antibodies against Leptospira serovars and of Leptospira DNA in the urine of a population of free-roaming cats.
Methods
Paired blood and urine samples were collected from 200 cats brought to a trap–neuter–return program. Antibody titers against six Leptospira serovars (Bratislava, Canicola, Gryppotyphosa, Hardjo, Pomona, Icterohaemorrhagiae) were determined by microscopic agglutination test. PCR was performed on urine samples to identify urine shedding of Leptospira DNA.
Results
Antibodies were detected in 20/200 cats (10%) for at least one serovar, with titers ranging from 1:50 to 1:6400 (all serovars tested, except Hardjo). Urine samples of 7/200 cats (3.5%) were PCR-positive.
Conclusions and relevance
Feral cats in Prince Edward Island (PEI) had a higher than expected exposure to leptospirosis and can shed DNA from pathogenic Leptospira species in urine. Further studies are needed to determine the prevalence of exposure to leptospirosis in other species on PEI and the potential role of feral cats in transmission of the disease.University of Prince Edward Islan
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