Proposed criteria for classification of acute myeloid leukemia in dogs and cats

Blood and bone marrow smears from 49 dogs and cats, believed to have myeloproliferative disorders (MPD), were examined by a panel of 10 clinical pathologists to develop proposals for classification of acute myeloid leukemia (AML) in these species. French-American-British (FAB) group and National Cancer Institute (NCI) workshop definitions and criteria developed for classification of AML in humans were adapted. Major modifications entailed revision of definitions of blast cells as applied to the dog and cat, broadening the scope of leukemia classification, and making provisions for differentiating erythremic myelosis and undifferentiated MPD. A consensus cytomorphologic diagnosis was reached in 39 (79.6%) cases comprising 26 of AML, 10 of myelodysplastic syndrome (MDS), and 3 of acute lymphoblastic leukemia (ALL). Diagnostic concordance for these diseases varied from 60 to 81% (mean 73.3 +/- 7.1%) and interobserver agreement ranged from 51.3 to 84.6% (mean 73.1 +/- 9.3%). Various subtypes of AML identified included Ml, M2, M4, M5a, M5b, and M6. Acute undifferentiated leukemia (AUL) was recognized as a specific entity. M3 was not encountered, but this subclass was retained as a diagnostic possibility. The designations M6Er and MDS-Er were introduced where the suffix "Er" indicated preponderance of erythroid component. Chief hematologic abnormalities included circulating blast cells in 98% of the cases, with 36.7% cases having >30% blast cells, and thrombocytopenia and anemia in approximately 86 to 88% of the cases. Bone marrow examination revealed panmyeloid dysplastic changes, particularly variable numbers of megaloblastoid rubriblasts and rubricytes in all AML subtypes and increased numbers of eosinophils in MDS. Cytochemical patterns of neutrophilic markers were evident in most cases of Ml and M2, while monocytic markers were primarily seen in M5a and M5b cases. It is proposed that well-prepared, Romanowsky-stained blood and bone marrow smears should be examined to determine blast cell types and percentages for cytomorphologic diagnosis of AML. Carefully selected areas of stained films presenting adequate cellular details should be used to count a minimum of 200 cells. In cases with borderline diagnosis, at least 500 cells should be counted. The identity of blast cells should be ascertained using appropriate cytochemical markers of neutrophilic, monocytic, and megakaryocytic differentiation. A blast cell count of > 30% in blood and/or bone marrow indicates AML or AUL, while a count of < 30% blasts in bone marrow suggests MDS, chronic myeloid leukemias, or even a leukemoid reaction. Myeloblasts, monoblasts, and megakaryoblasts comprise the blast cell count. The FAB approach with additional criteria should be used to distinguish AUL and various subtypes of AML (Ml to M7 and M6Er) and to differentiate MDS, MDS-ER, chronic myeloid leukemias, and leukemoid reaction. Bone marrow core biopsy and electron microscopy may be required to confirm the specific diagnosis. Immunophenotyping with lineage specific antibodies is in its infancy in veterinary medicine. Development of this technique is encouraged to establish an undisputed identity of blast cells. Validity of the proposed criteria needs to be substantiated in large prospective and retrospective studies. Similarly, clinical relevance of cytomorphologic, cytochemical, and immunophenotypic characterizations of AML in dogs and cats remains to be determined.     

Outbreak of cucumber mosaic virus on musa sp. in Tamil Nadu,India

Cucumber Mosaic Virus, or Infectious Chlorosis, was found in alarming proportions in all the districts of Tamil Nadu on the ‘Robusta’ (Dwarf Cavendish) and ‘Poovan’ (Mysore) cultivais. The disease was transmitted only through suckers from the diseased gardens. Among the genotypes screened, the clones with ABB genomes showed complete field resistance.     

Ultrastructural analysis of platelets and megakaryocytes from a dog with probable essential thrombocythemia

Blood platelets and bone marrow megakaryocytes from a dog with essential thrombocythemia were analyzed by transmission electron microscopy and compared with those of control dogs. Platelets varied in size and shape and contained enlarged and dilated open canalicular systems. Megakaryocytes were dysmorphic and had evidence of abnormal maturation, with large numbers of megakaryoblasts containing alpha granules and poorly organized and reduplicated demarcation membranes. The fewer, more mature megakaryocytes lacked normal cytoplasmic organization. Most notable was the absence of well-demarcated "platelet fields," due to the excessive and disorderly array of demarcation membranes.     

Potential Use of 3D CORAGRAF-Loaded PDGF-BB in PLGA Microsphere Seeded Mesenchymal Stromal Cells in Enhancing the Repair of Calvaria Critical-Size Bone Defect in Rat Model

Our previous study evidenced that the 3D CORAGRAF loaded with PLGA microsphere constitutes PDGF-BB can support cell attachment and proliferation and can induce an osteogenic commitment of mesenchymal stromal cells in the in vitro condition. However, how this construct can perform in pathophysiological conditions in terms of repairing critical bone defects is yet to be understood. A study was therefore conducted to investigate the regeneration potential of calvaria critical-size defects using CORAGRAF + PLGA with PDGF-BB + mesenchymal stromal cells (MSCs) in a rat model. A 5 mm critical bone defect was created on calvaria of 40 male Sprague-Dawley rats. CORAGRAF incorporated either with or without PDGF-BB and seeded with rat bone-marrow-derived MSCs was implanted at the defect region. The bone regeneration potential of implanted constructs was assessed using micro-CT imaging and histological staining in weeks 4 and 8. The micro-CT images indicated a significant closure of defects in the cranial bone of the rats treated with 3D CORAGRAF + PLGA with PDGF-BB + MSCs on week 4 and 8 post-implantation. This finding, further supported with the histology outcome where the rat cranial defect treated with CORAGRAF + PLGA with PDGF-BB + MSCs indicated neo-bony ingrowth with organized and mature bone-like morphology as compared with other groups. The previous in vitro results substantiated with our pre-clinical findings demonstrate that the combination of CORAGRAF + PLGA with PDGF-BB + MSCs could be an ideal construct to support bone regeneration in critical bone defects. Hence, this construct can be further investigated for its safety and efficacy in large animal models, or it can be skipped to human trial prior for commercialization.     

Improved micropropagation protocol and enhancement in biomass and chlorophyll content in Stevia rebaudiana (Bert.) Bertoni by using high copper levels in the culture medium

Incorporation of a range of higher concentrations of CuSO₄·5H₂O in MS medium [Murashige, T., Skoog, F., 1962. A revised medium for rapid growth and bioassay with 240 tobacco tissue cultures. Physiol. Plant 15, 473–497] significantly enhanced direct shoot bud induction and proliferation from cultured leaf and nodal explants taken from mature plants of Stevia rebaudiana. Shoot bud induction medium was supplemented with BAP (2.2 μM) and IAA (2.8 μM). When the concentration of CuSO₄·5H₂O in the induction medium was raised to 0.5 μM (five times the MS level, i.e. 0.1 μM) there was significant increase in percentage response along with increase in shoot bud number per explant. The shoots were healthy, well developed with dark green broader leaves. There was remarkable increase in total biomass and chlorophyll content at increased (0.5 μM) copper level in the medium. During proliferation stage also presence of high copper levels in the medium favoured increase in shoot bud number per explant.     

Prediction of irrigation return flows through a hierarchical modeling approach

The quantity of water available for irrigation is getting scarce in many countries and it assumes great importance for assured crop production, especially in view of the erratic behavior of the monsoon. Thus, there is a pressing need to improve the water efficiency of irrigation systems. One-way of improving the efficiency of the irrigation system is reusing the return flow from the irrigation system. This task requires quantification of return flow, which still remains as a grey area in irrigation water management. The estimation of return flow from the irrigation system is usually obtained using thumb rules depending upon the site-specific conditions like command area conditions and soil properties. In this paper, a hierarchical modeling technique, namely, regression tree is developed for return flow estimation. Regression tree is built through binary recursive partitioning. The effective rainfall, inflow, consumptive water demand, and percolation loss are taken as predictor variables and return flow is treated as the target variable. The applicability of the hierarchical model is demonstrated through a case study of Periyar-Vaigai Irrigation System in Tamil Nadu, India. The model performance shows a good match between the simulated and the field measured return flow values. Results of statistical analysis indicated that the correlation coefficients are high for both single as well as double crop seasons.     

The Prospects of Tissue Culture and Genetic Engineering for Strawberry Improvement

Abstract

Strawberry shoot meristem cultures have been used for producing virus-free strawberry plants. Plantlet regneration from leaf mesophyll protoplasts, and Agrobacterium tumefaciens mediated genetic transformation, mark the beginning of strawberry improvement with biotechnologies. The use of biotechnological tools has a greater potential in producing strawberry plants with traits such as early maturation, frost and disease resistance, mite and nematode resistance, high yield, better quality, suitability for mechanical harvesting, shipping ability, ellgaic acid content, aroma compounds and cost-effective micropropagation. Gene identification and mapping with RFLPs or RAPDs would be desirable. Transgenic strawberries should be tested for their quality before releasing to the consumers.     

Occurrence of a new leaf spot disease ofMusa sp. incited byThanatephorus cucumeris

A new leaf spot disease of banana(Musa sp.) cv. ‘Rasthali’ (syn. Silk) was observed in Tamil Nadu, in 1987. The causal organism was isolated in pure culture and identified asRhizoctonia solarii Kühn. The teleomorphic stage,Thanatephorus cucumeris (Frank) Donk, has also been induced artificially. This is the first record of this pathogen causing leaf spot disease onMusa sp. The pathogenicity of basidiospores on several other important crops was also tested.     

Unidentified coryneform bacterial strain from cases of polyarthritis in chickens: phenotype and fatty acid profile

We report isolation of a strain of fermentative coryneform bacteria from an outbreak of polyarthritis in chickens. This strain could not be assigned to any recognized bacterial taxon because its peculiar phenotype is not yet reported. The strain possessed phenotypic characteristics and fatty acid profile similar to Erysipelothrix but, on the other hand, exhibited temperature-dependent motility like Listeria. We found no evidence of either Mycoplasma synoviae or Chlamydia infection. Details of the phenotype and fatty acid profile of the isolate and measures undertaken to contain the outbreak have been described.