Implementation of two high through-put techniques in a novel application: detecting point mutations in large EMS mutated plant populations

Background  

The establishment of mutant populations together with the strategies for targeted mutation detection has been applied successfully to a large number of organisms including many species in the plant kingdom. Considerable efforts have been invested into research on tomato as a model for berry-fruit plants. With the progress of the tomato sequencing project, reverse genetics becomes an obvious and achievable goal.     

Hemagglutinating activity associated with bovine herpesvirus type 1

Using C57BL/HPB mouse erythrocytes, hemagglutination has been observed with the Los Angeles and Colorado-1 strains of bovine herpesvirus type 1 and with 12 other Canadian field isolates as well. The specificity of the hemagglutination observed with the viral strains has been confirmed by a hemagglutination-inhibition assay.     

Role of histone H3 lysine 27 methylation in X inactivation

The Polycomb group (PcG) protein Eed is implicated in regulation of imprinted X-chromosome inactivation in extraembryonic cells but not of random X inactivation in embryonic cells. The Drosophila homolog of the Eed-Ezh2 PcG protein complex achieves gene silencing through methylation of histone H3 on lysine 27 (H3-K27), which suggests a role for H3-K27 methylation in imprinted X inactivation. Here we demonstrate that transient recruitment of the Eed-Ezh2 complex to the inactive X chromosome (Xi) occurs during initiation of X inactivation in both extraembryonic and embryonic cells and is accompanied by H3-K27 methylation. Recruitment of the complex and methylation on the Xi depend on Xist RNA but are independent of its silencing function. Together, our results suggest a role for Eed-Ezh2-mediated H3-K27 methylation during initiation of both imprinted and random X inactivation and demonstrate that H3-K27 methylation is not sufficient for silencing of the Xi.     

Evaluation of an actinomycin-D-containing combination chemotherapy protocol with extended maintenance therapy for canine lymphoma

In this retrospective study, a 6-drug (prednisone, L-asparaginase, vincristine, cyclophosphamide, doxorubicin, and actinomycin-D) chemotherapy protocol with extended maintenance for the treatment of lymphoma was evaluated for efficacy and toxicity in 39 dogs. The complete remission rate was 97%, with a median progression-free survival (PFS) of 331 d. The median overall survival (OS) was 461 d. Of the variables evaluated for prognostic significance, only immunophenotype and sex were found to be prognostic. Dogs with T-cell lymphoma had shorter PFS and OS than dogs with B-cell lymphoma. Castrated male dogs had a shorter PFS and OS than spayed female dogs. Although the majority of dogs experienced one or more episodes of chemotherapy associated toxicity, the majority of these episodes were mild and self-limiting. The results of this study warrant further investigation into the value of extended maintenance therapy and inclusion of actinomycin-D in combination chemotherapy protocols for canine lymphoma.     

Equilibrative nucleoside transporter 3 deficiency perturbs lysosome function and macrophage homeostasis

Lysosomal storage diseases (LSDs) are a group of heterogeneous disorders caused by defects in lysosomal enzymes or transporters, resulting in accumulation of undegraded macromolecules or metabolites. Macrophage numbers are expanded in several LSDs, leading to histiocytosis of unknown pathophysiology. Here, we found that mice lacking the equilibrative nucleoside transporter 3 (ENT3) developed a spontaneous and progressive macrophage-dominated histiocytosis. In the absence of ENT3, defective apoptotic cell clearance led to lysosomal nucleoside buildup, elevated intralysosomal pH, and altered macrophage function. The macrophage accumulation was partly due to increased macrophage colony-stimulating factor and receptor expression and signaling secondary to the lysosomal defects. These studies suggest a cellular and molecular basis for the development of histiocytosis in several human syndromes associated with ENT3 mutations and potentially other LSDs.     

Comparison of bronchoalveolar lavage cytospins and smears in dogs and cats

Differences in the cytological interpretation of bronchoalveolar lavage fluid (BALF) after cytospin preparation (CP) or manual smearing of pelleted cells preparation (MSP) were investigated in client-owned dogs and cats with inflammatory or infectious lower respiratory disease. Bronchoalveolar lavage fluid from healthy cats was also examined. With MSP, cell lysis was more frequently observed, and cellular distribution was more heterogeneous throughout the slide. When samples from healthy and diseased animals were considered together, a significantly greater percentage of neutrophils was seen on CP than on MSP slides (P<0.002). Cytospin preparations were considered of better quality in all individual comparisons. Cytospin preparation is advised in the evaluation of BALF with low total cell count. When only MSPs are evaluated, clinicians should be aware that differential neutrophil counts may underestimate the counts found on CP slides.     

Managing the commons: An economic approach to pearl industry regulation

Abstract

In order to assess whether gender differences affect uptake and participation in aquacultural activities, a study of a cage aquaculture development project managed by a non‐governmental organization (NGO) in Bangladesh was undertaken. CAGES project (Cage Aquaculture for Greater Economic Security) aims to promote the use of low input cage systems for the benefit of the rural resource poor, including women. Using a participatory approach involving semi‐structured questionnaires complemented by group discussions with mapping exercises to cross‐check information, the role of women was investigated. Distance of the household from the water body was revealed as a major constraint to the full participation of women, especially in the more conservative areas of the country. Time‐consuming activities such as the collection and preparation of feed were generally the responsibility of women as part of their ‘household’ tasks. The influence women held over post‐harvest decisions varied between region, villages and households, with women in the Jessore area appearing to become more empowered from cage aquaculture activities. The implications of these findings are discussed with reference to the CAGES project and gender goals in development.     

In planta distribution of 'Candidatus Liberibacter asiaticus' as revealed by polymerase chain reaction (PCR) and real-time PCR

Huanglongbing (HLB) is one of the most devastating diseases of citrus worldwide, and is caused by a phloem-limited fastidious prokaryotic alpha-proteobacterium that is yet to be cultured. In this study, a combination of traditional polymerase chain reaction (PCR) and real-time PCR targeting the putative DNA polymerase and 16S rDNA sequence of 'Candidatus Liberibacter asiaticus,' respectively, were used to examine the distribution and movement of the HLB pathogen in the infected citrus tree. We found that 'Ca. Liberibacter asiaticus' was distributed in bark tissue, leaf midrib, roots, and different floral and fruit parts, but not in endosperm and embryo, of infected citrus trees. Quantification analysis of the HLB bacterium indicated that it was distributed unevenly in planta and ranged from 14 to 137,031 cells/mug of total DNA in different tissues. A relatively high concentration of 'Ca. Liberibacter asiaticus' was observed in fruit peduncles. Our data from greenhouse-infected plants also indicated that 'Ca. Liberibacter asiaticus' was transmitted systemically from infection site to different parts of the plant. Understanding the distribution and movement of the HLB bacterium inside an individual citrus tree is critical for discerning its virulence mechanism and to develop management strategies for HLB.     

Combined effect of using near‐infrared spectroscopy for nutritional evaluation of feed ingredients and non‐starch polysaccharide carbohydrase complex on performance of broiler chickens

This study was carried out to evaluate the combined effect of using near‐infrared spectroscopy (NIRS ) for nutritional evaluation of feed ingredients and the addition of non‐starch polysaccharide carbohydrase complex (NSP enzymes) on the growth performance of broilers fed diets produced with low‐quality wheat and soybean meal. A 2 × 2 trial design was performed, with seven replicates of 40 male Ross 308 broilers per treatment, evaluating the effect of the addition of NSP enzymes and the ingredients’ nutritional matrix based on table values or NIRS values. Diets without added enzymes were formulated to reach nutritional requirements, whereas diets with enzymes were reformulated, reducing the apparent metabolizable energy (AME ) by 85 kcal/kg. In the overall period (days 0–35), broilers fed diets formulated using NIRS values had higher (P  < 0.001) average daily gain (+11.3%) and daily feed intake (+7.2%), and a lower (P  < 0.001) feed conversion ratio (?5.3%) compared to those fed diets formulated using table values. When formulating diets for broilers with low‐quality feed ingredients, performance can be improved by considering NIRS values and by the addition of NSP enzymes, even with a reduction of AME . These nutritional approaches are efficient in improving broilers’ performances by themselves and even more so when they are combined.