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Voytenko AV Kanbar T Alber J Lämmler C Weiss R Prenger-Berninghoff E Zschöck M Akineden O Hassan AA Dmitrenko OA 《Veterinary microbiology》2006,116(1-3):211-216
A species specific PCR test, based on manganese-dependent superoxide dismutase A encoding gene sodA, was developed for the identification of Staphylococcus hyicus, an important bacterial pathogen in pigs. The designed primers allowed a rapid and reliable identification of phenotypically characterized S. hyicus, isolated in Russia, Germany and Denmark. No cross reactivities could be observed investigating staphylococcal reference strains representing 18 different species and subspecies. The use of the described primers might improve a future diagnosis of this bacterial pathogen. 相似文献
95.
OBJECTIVE: To evaluate activation of Jun N-terminal kinase/stress-activated protein kinase (JNK/SAPK) pathway in bovine monocytes after incubation with Mycobacterium avium subsp paratuberculosis (Mptb) organisms. SAMPLE POPULATION: Bovine monocytes obtained from 4 healthy adult Holstein dairy cows. PROCEDURES: Bovine monocytes were incubated with Mptb organisms with or without a specific inhibitor of the JNK/SAPK pathway (SP600125) for 2, 6, 24, or 72 hours. Expression of interleukin (IL)-1beta, IL-10, IL-12, IL-18; transforming growth factor-beta (TGF-beta); and tumor necrosis factor-alpha (TNF-alpha) and the capacity of Mptb-infected monocytes to acidify phagosomes and kill Mptb organisms were evaluated. Phosphorylation status of JNK/SAPK was evaluated at 10, 30, and 60 minutes after Mptb incubation. RESULTS: Compared with uninfected control monocytes, Mptb-infected monocytes had increased expression of IL-10 at 2 and 6 hours after incubation and had increased expression of TNF-alpha, IL-1beta, IL-18, and TGF-beta at 2, 4, and 6 hours. Additionally, Mptb-infected monocytes had increased expression of IL-12 at 6 and 24 hours. Addition of SP600125 (specific chemical inhibitor of JNK/SAPK) resulted in a decrease in TNF-alpha expression at 2, 6, and 24 hours, compared with untreated Mptb-infected cells. Addition of SP600125 resulted in a decrease in TGF-beta expression at 24 hours and an increase in IL-18 expression at 6 hours. Addition of SP600125 failed to alter phagosome acidification but did enhance the capacity of monocytes to kill Mptb organisms. CONCLUSIONS AND CLINICAL RELEVANCE: Activation of JNK/SAPK may be an important mechanism used by Mptb to regulate cytokine expression in bovine monocytes for survival and to alter inflammatory and immune responses. 相似文献
96.
Weiss DJ 《Journal of the American Veterinary Medical Association》2006,228(6):893-897
OBJECTIVE: To further classify dysmyelopoiesis as diagnosed by use of a general classification scheme and to determine clinical features and laboratory test results that could be used to differentiate between the various forms of dysmyelopoiesis in cats. DESIGN: Retrospective case series. Sample Population-Bone marrow slides from 34 cats. PROCEDURES: Medical records of cats in which dysmyelopoiesis was diagnosed on the basis of blood and bone marrow analyses from 1996 to 2005 were reviewed. Criteria for inclusion in the study were findings of > 10% dysplastic cells in 1 or more hematologic cell lines in the bone marrow and concurrent cytopenias in the blood. Cats that met these criteria were classified into subcategories of myelodysplastic syndromes or secondary dysmyelopoiesis on the basis of reevaluation of slides. RESULTS: Of 189 bone marrow slides reviewed, 34 (14.9%) had > 10% dysplastic cells in 1 or more cell lines. Cats were subcategorized as having myelodysplastic syndrome with excessive numbers of blast cells (n = 13), myelodysplastic syndrome with refractory cytopenias (8), a variant form of myelodysplastic syndrome (1), and secondary dysmyelopoiesis (12). Findings of dysmyelopoiesis and autoagglutination in cats with myelodysplastic syndrome and in those with immune-mediated anemia complicated differentiating between the 2 conditions. CONCLUSIONS AND CLINICAL RELEVANCE: Differentiating cats with myelodysplastic syndromes from cats with immune-mediated hemolytic anemia was difficult because severe anemia and autoagglutination may be concurrent findings in both conditions. Differentiating between myelodysplastic syndrome with excessive numbers of blast cells and myelodysplastic syndrome with refractory cytopenias was useful in predicting clinical outcome. 相似文献
97.
C Betthausen T Dollinger H Saarikoski V Kolkovsky G Karczewski T Wojtowicz K Richter D Weiss 《Science (New York, N.Y.)》2012,337(6092):324-327
Spin-transistor designs relying on spin-orbit interaction suffer from low signal levels resulting from low spin-injection efficiency and fast spin decay. Here, we present an alternative approach in which spin information is protected by propagating this information adiabatically. We demonstrate the validity of our approach in a cadmium manganese telluride diluted magnetic semiconductor quantum well structure in which efficient spin transport is observed over device distances of 50 micrometers. The device is turned "off" by introducing diabatic Landau-Zener transitions that lead to a backscattering of spins, which are controlled by a combination of a helical and a homogeneous magnetic field. In contrast to other spin-transistor designs, we find that our concept is tolerant against disorder. 相似文献
98.
GK Wong MS Kang HW Lee F Biancalana C Conti T Weiss PS Russell 《Science (New York, N.Y.)》2012,337(6093):446-449
Spiral twisting offers additional opportunities for controlling the loss, dispersion, and polarization state of light in optical fibers with noncircular guiding cores. Here, we report an effect that appears in continuously twisted photonic crystal fiber. Guided by the helical lattice of hollow channels, cladding light is forced to follow a spiral path. This diverts a fraction of the axial momentum flow into the azimuthal direction, leading to the formation of discrete orbital angular momentum states at wavelengths that scale linearly with the twist rate. Core-guided light phase-matches topologically to these leaky states, causing a series of dips in the transmitted spectrum. Twisted photonic crystal fiber has potential applications in, for example, band-rejection filters and dispersion control. 相似文献
99.
Koehler JW Weiss RC Aubry OA Smith AN Hathcock JT Brawner WR 《Veterinary pathology》2012,49(5):870-875
An intact, 8-year-old, male Golden Retriever dog was presented for evaluation of a nasal mass and approximately 30 firm, raised, variably ulcerated dermal and subcutaneous masses. Histopathology of both nasal and multiple skin masses revealed multiple nonencapsulated, infiltrative masses comprising clusters, anastomosing trabeculae, and packets of neoplastic, round to ovoid, hyperchromatic cells with marked nuclear molding. Surrounding the neoplastic cells was a marked stromal response in which many of the spindle-shaped cells expressed muscle-specific actin and had ultrastructural features consistent with myofibroblasts. A literature search indicates that this is the first report in a peer-reviewed journal of cutaneous metastasis of a nasal neuroendocrine tumor in any domestic animal species. 相似文献
100.
Traditionally, chapattis are flatbreads made from atta (wholemeal Indian wheat flour). Non-atta chapattis have not been popular due to substandard product quality. To investigate what makes atta special for making chapattis, products were made using atta, Australian wholemeal wheat flour, gluten-free lupin flour, and a blend of lupin and wheat flours. Doughs were characterised by measuring strain-hardening and elastic recovery in compression and also bubble structures via 3-D X-ray micro-tomography. A method was developed to identify and separate bran, which appears as bubbles, in scans of doughs. 相似文献