Diagnosis of canine lymphoid neoplasia using clonal rearrangements of antigen receptor genes   总被引：3，自引：0，他引：3  

Burnett RC  Vernau W  Modiano JF  Olver CS  Moore PF  Avery AC 《Veterinary pathology》2003,40(1):32-41

Although the diagnosis of canine leukemia and lymphoma in advanced stages is usually uncomplicated, some presentations of the disease can be a diagnostic challenge. In certain situations, lymphoma and leukemia can be difficult to distinguish from a benign reactive proliferation of lymphocytes. Because clonality is the hallmark of malignancy, we have developed an assay that uses the polymerase chain reaction to amplify the variable regions of immunoglobulin genes and T-cell receptor genes to detect the presence of a clonal lymphocyte population. The assay detected clonally rearranged antigen receptor genes in 91% of the 77 dogs with lymphoid malignancy. Of the 24 dogs tested, that were either healthy or had clearly defined conditions not related to lymphoid malignancy, a clonally rearranged antigen receptor gene was found in one (a dog with Ehrlichia canis infection). Gene rearrangement was appropriate for the immunophenotype (immunoglobulin gene rearrangement in B-cell leukemias and T-cell receptor gene rearrangement in T-cell leukemias). Dilution analysis showed that the clonal rearrangement could be detected when 0.1-10% of the DNA was derived from neoplastic cells, depending on the source tissue. Potential applications of this assay include the diagnosis of lymphoma or leukemia in biopsy samples, cavity fluids, fine needle aspirates, bone marrow and peripheral blood; the determination of lineage (B or T cell); staging of lymphoma; and detection of residual disease after chemotherapy.  相似文献   

Use of the Cell-Dyn 3500 to predict leukemic cell lineage in peripheral blood of dogs and cats   总被引：1，自引：0，他引：1  

Fernandes PJ  Modiano JF  Wojcieszyn J  Thomas JS  Benson PA  Smith R  Avery AC  Burnett RC  Boone LI  Johnson MC  Pierce KR 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2002,31(4):167-182

Background— Morphology and cytochemistry are the foundation for classification of leukemias in dogs and cats. Advances in automated hematology instrumentation, immunophenotyping, cytogenetics, and molecular biology are significantly improving our ability to recognize and classify spontaneous myeloproliferative and lymphoproliferative disorders. Objective— The purpose of this study was to assess the utility of flow cytometry‐based light scatter patterns provided by the Cell‐Dyn 3500 (CD3500) automated hematology analyzer to predict the lineage of leukemic cells in peripheral blood of dogs and cats. Methods— Leukemic cells from 15 dogs and 6 cats were provisionally classified using an algorithm based on the CD3500 CBC output data and were subsequently phenotyped by enzyme cytochemistry, immunocytochemistry, indirect flow cytometry, and analysis of antigen receptor gene rearrangement. Results— The algorithm led to correct predictions regarding the ontogeny of the leukemic cells (erythroid/megakaryocytic potential, myeloid leukemia, monocytic leukemia, chronic granulocytic leukemia, lymphoid leukemia) in 19/21 animals. Mismatches in the WBC impedance count and the WBC optical count in conjunction with microscopic assessment of blasts in the blood were useful for predicting myeloproliferative disorders with erythroid or megakaryocytic potential. The leukocyte light scatter patterns enabled distinction among myeloid leukemias (represented by acute myelomonocytic leukemia, acute monocytic leukemia, chronic granulocytic leukemia) and lymphocytic leukemias (including acute and chronic lymphocytic leukemias). One case of acute lymphocytic leukemia was misidentified as chronic lymphocytic leukemia. Conclusions— Algorithmic analyses can be applied to data generated by the CD3500 to predict the ontogeny of leukemic cells in the peripheral blood of dogs and cats. This rapid and quantitative technique may be used to improve diagnostic decisions, expand therapeutic choices, and increase prognostic accuracy.  相似文献   

Histopathological Study of Barley Cultivars Resistant and Susceptible to Rhynchosporium secalis     

Carisse KX  Burnett PA  Tewari JP  Chen MH  Turkington TK  Helm JH 《Phytopathology》2000,90(1):94-102

ABSTRACT Differences in the penetration process by Rhynchosporium secalis were compared in resistant and susceptible barley cultivars at the seedling stage. Percent penetration and percent host cell wall alteration (HCWA) differed significantly among cultivars and isolates as revealed by light microscopy. Based on these two variables, the cultivars were statistically separated into two groups that corresponded to their disease reactions. The resistant cultivars, Johnston and CDC Guardian, showed 81.2 to 99.4% HCWA and 0.1 to 20.1% penetration at encounter sites, whereas the susceptible cultivars, Harrington, Argyle, and Manley, had 30.1 to 78.3% HCWA and 31.8 to 81.8% penetration. In the current study, cv. Leduc, which is susceptible at the seedling stage and resistant at the adult stage, showed the same percent HCWA and penetration as did susceptible cultivars. A significant negative correlation (P < 0.01) was found between percent penetration and percent HCWA for cultivars inoculated with two isolates of the pathogen. Isolate 1 was less virulent than isolate 2 with respect to percent penetration and induced significantly fewer HCWA. Scanning electron microscopy showed various shapes of fungal appressoria but no apparent difference in host reaction between resistant and susceptible cultivars. Transmission electron microscopy revealed interactions between the host and pathogen at various stages of penetration. The resistant cv. Johnston responded by producing appositions, as evidenced by a layer of compact osmiophilic material deposited on the inner side of the cell wall. Infection pegs produced by conidia were unable to penetrate the cuticle where an apposition had formed inside. When penetration occurred in the susceptible cv. Argyle, cytoplasmic aggregates and separation of the plasmalemma were visible from the host cell wall, but the layer of compact osmiophilic material was not always present. Data based on light microscopic observations suggested that HCWA may be one of the mechanisms responsible for resistance that is characterized as penetration prevention rather than as a slow rate of mycelial growth after successful penetration. HCWA occurred in response to attempted cuticle penetration, suggesting that HCWA may produce chemical barriers that help to prevent penetration.  相似文献   

Descriptive analysis of horses and ponies attending horse auctions in Victoria from July 2019 to March 2020     

GR Chapman  B Wells  JR Gilkerson  ML Flash 《Australian veterinary journal》2023,101(1-2):1-8

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‘Pasifika’ and ‘I‐Kiribati’ identity in Aotearoa New Zealand: ‘Dancing’ and ‘edge‐walking’ through multiple identities     

Roi Burnett  Sophie Bond 《Asia Pacific viewpoint》2020,61(2):327-337

This article explores the relationship between I‐Kiribati communities and the broader ‘imagined’ Pasifika community in Aotearoa New Zealand. It looks at the way a group of I‐Kiribati tertiary students experience identity within this context. Through the use of semi‐structured interviews and a discourse analysis, the study draws three main conclusions. First, that I‐Kiribati navigate multiple identities and are constantly negotiating these within different spaces. Although this contributes to uncertainties around identity, I‐Kiribati students also strategically enact identity to suit various contexts. Second, that Pasifika as a term tends to infer ‘Polynesian’ which in turn may marginalise I‐Kiribati identities within certain spaces, particularly in education settings that intend to support all Pacific identities. Yet, given such a narrow understanding of Pasifika, these efforts may counter that intention for those on the margins of, or outside the common usage of, the term Pasifika. Last, community plays a significant role in the formation of identities within minority groups, which is important for countering aspects of marginalisation experienced within broader pan‐ethnic labels such as Pasifika. Consequently, we argue that Pasifika as a label needs to better reflect inter‐Pacific diversity as well as the identity negotiations that Aotearoa New Zealand‐born Pacific peoples navigate.  相似文献   

Harvest interval affects lucerne (Medicago sativa L.) taproot total yield,starch, nitrogen and water-soluble carbohydrates     

Meredith L. Mitchell  Stephen G. Clark  Kym L. Butler  Zhongnan Nie  Vivianne F. Burnett  Richard Meyer  Reto Zollinger  Gregory R. Seymour 《Journal of Agronomy and Crop Science》2020,206(5):619-629

Lucerne (Medicago sativa L.) has a large taproot to store and release starch, carbohydrates and nutrients during the plant's growth. Recommended management of the lucerne crop aims to keep the taproot stable subject to the demands for feed provision and stand longevity. Field experiments were conducted in Victoria, Australia, to examine the effects of recovery period on taproot mass and nutritive status. Both experiments used established SARDI Seven lucerne crops and were either cut every 21 days (short recovery SR) or every 42 days (long recovery LR). At each defoliation, taproots were extracted for determination of DM yield and starch, water-soluble carbohydrate (WSC) and nitrogen (N) concentration and DM yield. At both sites, WSC and N DM yields along with total taproot DM yield did not change greatly as the experiment progressed. Starch was responsive to herbage accumulation with both concentration and DM yield, increasing when herbage accumulation rates were high and decreasing when herbage accumulation rates were low. At both sites, LR taproots had starch levels equal to or higher than those of SR taproots. We conclude that short intervals between defoliations disrupt the energy cycling between shoots and roots. This is likely to reduce lucerne productivity, particularly during periods of rapid growth.  相似文献   

Diagnosis of mediastinal masses in dogs by flow cytometry     

Lana S  Plaza S  Hampe K  Burnett R  Avery AC 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2006,20(5):1161-1165

BACKGROUND: Biopsy of mediastinal masses can be invasive, but the procedure may be necessary if cytology of a mass aspirate is inconclusive. The 2 most common mediastinal masses, lymphoma and thymoma, may both be comprised of small lymphocytes. We investigated the ability of flow cytometry to distinguish between these 2 neoplasms. HYPOTHESIS: Flow cytometry of mediastinal mass aspirates may provide a definitive diagnosis of thymoma or lymphoma, reducing the need for biopsy. ANIMALS: Dogs with mediastinal masses presenting to the Veterinary Teaching Hospital/Animal Cancer Center were included in the study. METHODS: Aspirates obtained over 2 years that met the inclusion criteria (i.e. sufficient viable cells and a definitive diagnosis by means other than flow cytometry) were analyzed by flow cytometry to determine the percentage of cells expressing B- and T-cell markers, and co-expressing CD4 and CD8. RESULTS: All cases of thymoma (n = 6) consisted of > or = 10% lymphocytes coexpressing CD4 and CD8, a phenotype that is characteristic of thymocytes, whereas 6 of 7 lymphomas contained <2% CD4+CD8+ lymphocytes. The CD4+CD8+ lymphoma could be readily distinguished flow cytometrically from thymoma by light scatter properties. The phenotypes of the remaining lymphomas were CD4+ T cell (4), CD34+ (1) and B cell (1). CONCLUSIONS: Our studies demonstrate that flow cytometry is a useful tool for discriminating mediastinal masses. Lymphocyte-rich mediastinal masses could be unambiguously identified by flow cytometry in 13/13 cases.  相似文献   

From pedigree cats to fluffy-bunnies     

Dunningham J  Rau A  Burnett K 《Science (New York, N.Y.)》2005,307(5711):872-875

We consider two distinct classes of quantum mechanical entanglement. The first "pedigree" class consists of delicate highly entangled states, which hold great potential for use in future quantum technologies. By focusing on Schrodinger cat states, we demonstrate not only the possibilities these states hold but also the difficulties they present. The second "fluffy-bunny" class is made up of robust states that arise naturally as a result of measurements and interactions between particles. This class of entanglement may be responsible for the classical-like world we see around us.  相似文献   

Evidence for Widespread 26Al in the Solar Nebula and Constraints for Nebula Time Scales     

SS Russell  G Srinivasan  GR Huss  GJ Wasserburg  GJ MacPherson 《Science (New York, N.Y.)》1996,273(5276):757-762

A search was made for 26Mg (26Mg*) from the decay of 26Al (half-life = 0.73 million years) in Al-rich objects from unequilibrated ordinary chondrites. Two Ca-Al-rich inclusions (CAIs) and two Al-rich chondrules (not CAIs) were found that contained 26Al when they formed. Internal isochrons for the CAIs yielded an initial 26Al/27Al ratio [(26Al/27Al)0] of 5 x 10(-5), indistinguishable from most CAIs in carbonaceous chondrites. This result shows that CAIs with this level of 26Al are present throughout the classes of chondrites and strengthens the notion that 26Al was widespread in the early solar system. The two Al-rich chondrules have lower 26Mg*, corresponding to a (26Al/27Al)0 ratio of approximately 9 x 10(-6). Five other Al-rich chondrules contain no resolvable 26Mg*. If chondrules and CAIs formed from an isotopically homogeneous reservoir, then the chondrules with 26Al must have formed or been last altered approximately2 million years after CAIs formed; the 26Mg*-free chondrules formed >1 to 3 million years later still. Because 26Mg*-containing and 26Mg*-free chondrules are both found in Chainpur, which was not heated to more than approximately400°C, it follows that parent body metamorphism cannot explain the absence of 26Mg* in some of these chondrules. Rather, its absence indicates that the lifetime of the solar nebula over which CAIs and chondrules formed extended over approximately5 million years.  相似文献   

ON THE ENCOURAGEMENT OF MR. CHARLES D. SNYDER     

Loeb J  Robertson TB  Maxwell SS  Burnett TC 《Science (New York, N.Y.)》1908,28(723):645-648

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