Pathophysiology of Diarrhea in Calves     

D.M. Foster  Geof W. Smith  DVM  MS  PhD 《Veterinary Clinics of North America: Food Animal Practice》2009

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The contribution of the synovium, synovial derived inflammatory cytokines and neuropeptides to the pathogenesis of osteoarthritis     

Sutton S  Clutterbuck A  Harris P  Gent T  Freeman S  Foster N  Barrett-Jolley R  Mobasheri A 《Veterinary journal (London, England : 1997)》2009,179(1):10-24

Osteoarthritis (OA) is one of the most common and disabling chronic joint disorders affecting horses, dogs and humans. Synovial inflammation or synovitis is a frequently observed phenomenon in osteoarthritic joints and contributes to the pathogenesis of OA through formation of various catabolic and pro-inflammatory mediators altering the balance of cartilage matrix degradation and repair. Catabolic mediators produced by the inflamed synovium include pro-inflammatory cytokines, nitric oxide, prostaglandin E(2) and several neuropeptides, which further contribute to the pathogenesis of OA by increasing cartilage degradation. Recent studies suggest that substance P, corticotropin-releasing factor, urocortin and vasoactive intestinal peptide may also be involved in OA development, but the precise role of these neuropeptides in the pathogenesis of OA is not known. Since increased production of matrix metalloproteinases by the synovium is stimulated by pro-inflammatory cytokines, future anti-inflammatory therapies should focus on the synovium as a means of controlling subsequent inflammatory damage.  相似文献   

Fast characterization of industrial soy protein isolates by direct analysis with matrix-assisted laser desorption ionization time-of-flight mass spectrometry     

Horneffer V  Foster TJ  Velikov KP 《Journal of agricultural and food chemistry》2007,55(26):10505-10508

Industrial soy protein isolates (SPIs) due to differences in their processing conditions may differ both in composition and in degree of hydrolysis. As a result, they display different performance in food production and final food properties like consistency and taste. To address this issue, a fast, cheap, and simple method for screening and characterization is required. In this article, the successful analysis of soy protein isolates, a complex mixture of proteins with glycinin and beta-conglycinin as major components, by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF-MS) is demonstrated. The preparation implements a fast extraction of the proteins from the raw SPI either under neutral or reducing conditions. The extracts are analyzed subsequently by MALDI-TOF-MS without further purification. Results of the two conditions are compared. Finally, different SPIs from different suppliers are analyzed and compared concerning their consistency. The method could be applied to other plant proteins and mixtures thereof. Since the composition and intactness of different subunits play important roles in functional properties of soy proteins, rapid methods for fingerprinting of different industrial soy protein sources will be valuable tools for successful product formulation.  相似文献   

Predation history and vulnerability: Conservation of the stickleback adaptive radiation     

John A. Baker  Matthew A. Wund  Lauren Ackein  Susan A. Foster 《Biological conservation》2010,143(5):1184-1192

Recent adaptive radiations offer special insight into the processes that generate biodiversity. The loss of unique members of such radiations undermines their collective evolutionary potential, as well as the ability of scientists to compare divergent populations, thereby devaluing the entire radiation as a system of study. To illustrate our case, we consider the adaptive radiation of the threespine stickleback fish (Gasterosteus aculeatus) in light of anthropogenic threats. Specifically, we consider the effects of stocking with rainbow trout, Onchorynchus mykiss, on populations of stickleback in lakes of two types in the Cook Inlet Region of Alaska, USA: (1) those in which salmonids are native and (2) those historically devoid of predatory fish. Many populations in this second class exhibit reduced pelvic armor that is, in part, a consequence of the historical absence of piscine predators that prey upon stickleback. Long-term trapping data from 77 lakes show that stocking in lakes where trout are not native is associated with large fluctuations in stickleback abundance, relative to lakes in which trout are native, or to lakes in which trout are neither native nor stocked. Pelvic-reduced populations appear to be at most risk from stocking. We discuss how these populations have responded to, and may yet respond to such threats, and how the information we have on these populations can be used to identify evolutionarily significant units (ESUs: Ryder, 1986), and certainly, distinct populations segments (DPSs: [Green, 2005], [Moritz, 2002] and [Waples, 1991]) deemed worthy of protection under Section 3(15) of the 1973 US Endangered Species Act as amended in 1978. Finally, we consider relevance of our results to the conservation of other recent adaptive radiations.  相似文献   

The percolation phase transition in sea Ice   总被引：1，自引：0，他引：1  

KM Golden  SF Ackley  VI Lytle 《Science (New York, N.Y.)》1998,282(5397):2238-2241

Sea ice exhibits a marked transition in its fluid transport properties at a critical brine volume fraction pc of about 5 percent, or temperature Tc of about -5 degreesC for salinity of 5 parts per thousand. For temperatures warmer than Tc, brine carrying heat and nutrients can move through the ice, whereas for colder temperatures the ice is impermeable. This transition plays a key role in the geophysics, biology, and remote sensing of sea ice. Percolation theory can be used to understand this critical behavior of transport in sea ice. The similarity of sea ice microstructure to compressed powders is used to theoretically predict pc of about 5 percent.  相似文献   

Extraction and Activation of Wheat Polyphenol Oxidase by Detergents: Biochemistry and Applications     

Aravind K. Jukanti  Phil L. Bruckner  Debra K. Habernicht  Curt R. Foster  John M. Martin  Andreas M. Fischer 《Cereal Chemistry》2003,80(6):712-716

Polyphenol oxidases (PPOs) from several plant species, including wheat, have been implicated in undesirable brown discolorations of food products. It has been demonstrated that these enzymes are often present in a latent form or are membrane‐associated, necessitating detergent or other treatments to obtain fully active preparations. Here, the influence of different detergents on wheat meal and flour PPOs was investigated. Extraction in presence of 50 mM SDS led to a 5‐ to 15‐fold increase in PPO activity, making quantitative assays in flour from low‐PPO lines more robust. Among a series of additional nonionic, anionic, and cationic detergents tested, only n ‐lauroylsarcosine increased extractable PPO activity to a degree comparable to that of SDS. Additional experiments suggested that a large fraction of wheat meal PPOs may be membrane‐associated and that SDS is able to activate PPOs extracted from high‐activity but not from low‐activity wheat lines. PPO activities assayed after SDS extraction of meal and flour were highly correlated with each other and with activity determined in whole (intact) kernels in absence of SDS. Correlation coefficients between PPO activities measured with all these methods and noodle brightness were about equal, indicating that activities assayed after SDS extraction are useful for germplasm screening and quality prediction.  相似文献