Method for Blind Catheter Placement in the Equine Pulmonary Artery

The navigation behavior of catheters within the equine pulmonary artery (PA) was investigated using en bloc heart and lung preparations for the purpose of developing a method of blind catheter placement. An equine ex vivo heart and lung perfusion system with controlled perfusate pulsatile flow, pressure, and temperature was used to evaluate a blind navigation technique for placement of balloon-tipped catheters into the distal main stem of the PA. Catheter performance was observed with an intravascular endoscope. Three balloon catheters were selected for navigation trials: a 4 mm diameter × 1.2 cm, 2.7Fr, 142 cm angioplasty catheter (C4mm); a 10 mm diameter × 4 cm, 5Fr, 150-cm angioplasty catheter (C10mm); and a 16-mm diameter, 7Fr, 200-cm pancreatic duct sphincteroplasty catheter (C16mm). Successful catheter placement was defined as insertion within a left or right main stem of the PA to a distance greater than 20 cm beyond the bifurcation. A method of blind catheter placement into the distal main stem of the equine PA using balloon-tipped catheters was successfully developed. The 16-mm catheter was superior with an average proportion of successful insertions (PSIavg) of 93.6%; an average insertion distance in the main stem (IDMavg) of 30.1 ± 5.7 cm; and an average insertion distance anywhere in the PA (IDAavg) of 29.3 ± 6.4 cm versus the 10 mm (PSIavg 25%, IDMavg 39.3 ± 11.4 cm, IDAavg 19.3 ± 15.1 cm) and 4 mm (PSIavg 11%, IDMavg 40.0 ± 11.0 cm, IDAavg 12.8 ± 13.2 cm), respectively.     

寄生虫的反式剪接研究进展

从锥虫可变表面糖蛋白 ( VSG)中发现反式剪接以来 ,已经发现很多低等真核生物体内都存在这种剪接形式。这种广泛存在于低等真核生物中的反式剪接 ,对于生物蛋白多样性、阶段性表达有着重要的生物学意义。反式剪接中的反式剪接引导序列 ( spliced leader,SLRNA)为一段保守序列 ,SL RNA为寄生虫的功能基因的筛选、c DNA文库的构建提供了表达基因标签 ( EST) ,同时反式剪接为转基因治疗提供了有力的手段。反式剪接的发现和广泛研究 ,对于深入了解低等真核生物的核酸分子生物学及其起源、进化、系统发生、寄生虫病的预防研究等都有着重要意义。文章对反式剪接在低等真核生物体中的研究现状、SL RNA基本结构、生物学特点及其在现代分子生物学领域的应用进行了概述     

Modeling Soil Organic Carbon with DNDC and RothC Models in Different Wheat-Based Cropping Systems in North-Western India

ABSTRACT

The performance of DNDC (DeNitrification-DeComposition) and RothC (Rothamsted Carbon model) in simulating soil organic carbon (SOC) storage in soils under rice (Oryza sativa L.) – wheat (Triticum aestivum L.), maize (Zea mays L.) – wheat and cotton (Gossypium hirsutum L.) – wheat cropping systems was evaluated on field and regional scale. Field experiments consisted of N, NP, NK, PK, NPK, FYM, N + FYM, NPK + FYM, and control (UF) treatments. DNDC and RothC over-estimated SOC storage by 0.35–1.16 Mg C ha^?1 (6–21%) in surface layer with manure application, compared with inorganic fertilizer treatments by 1.01–1.16 Mg C ha^?1 (14–18%). Although RothC only slightly over-estimated SOC stocks, DNDC provided a better match for measured versus simulated SOC stocks (R ² = 0.783*, DNDC; 0.669*, RothC, p < .05). Model validation on independent datasets from long-term studies on rice–wheat (R ² = 0.935**, DNDC; R ² = 0.920**, RothC, p < .01) and maize–wheat (R ² = 0.895** for DNDC and R ² = 0.967** for RothC, p < .01) systems showed excellent agreement between measured and simulated SOC stocks. On a regional scale, change in SOC storage under Scenario 1 (NPK) was significant up to 8 years of simulation, with no change thereafter. In Scenario 2 (NPK + FYM), DNDC simulated SOC storage after 10 years was 2.0, 0.4, and 1.4 Mg C ha^?1 in three systems, respectively. Amount of C sequestered in silt + clay fraction varied between 0.31 and 0.97 kg C 10 years^?1 (Mg silt + clay)^?1 under Scenario 1, and between 0.78 and 2.67 kg C 10 years^?1 (Mg silt + clay)^?1 under Scenario 2.     

Competitive indices of wheat + compact-mustard intercropping in a 5:1 row proportion as influenced by fertilizer doses and seed rates of wheat varieties

A field experiment in a split-plot design with three replications was conducted on wheat + compact-mustard intercropping in a 5:1 row proportion at the research farm, Institute of Agricultural Sciences, Banaras Hindu University, India, during the winter seasons of 2005.–2006 and 2006.–2007. The main plot treatment involved a combination of three fertilizer doses [100, 120 and 140% recommended fertilizer dose (RFD) to wheat, accompanied by 100% RFD to mustard] and two wheat varieties (HD-2824 and HUW-468); the subplot treatment consisted of three seed rates of wheat (100, 115 and 130 kg ha^?1). The treatment differences were studied intensively in light of the various reciprocity indices. Wheat variety HD-2824 at 115 kg ha^?1 seed rate and 140% RFD, intercropped with compact-mustard variety Sanjukta Aschesh at 100% RFD in a 5:1 row proportion, resulted in the best land utilization, maximum productivity and monetary advantage. Among the various yield indices studied, area time equivalent ratio (ATER), competitive ratio (CR) and effective land equivalent ratio (LER) curves were found to be good for comparing the variations in fertilizer doses and seed rates used in wheat varieties. Nevertheless, to compare monetary advantage, the monetary advantage index (MAI) based on LER proved a better index than intercropping advantage (IA), which is based on actual yield loss (AYL).     

Effect of N-modified lignite granulates and composted biochar on plant growth,nitrogen and water use efficiency of spring wheat

ABSTRACT

Organic soil amendments such as biochar are increasingly used to improve the fertility of degraded soils and marginal lands, plant growth, water retention and carbon sequestration. The performance of biochar depends on the parent material, the pyrolysis conditions and the nutrient enrichment process, accounting for the variability of the final products. Recently lignite granulates came into focus offering an alternative characterised by homogeneity, vast availability of the raw material and a standardised production process including nitrogen enrichment through oxidative ammonolysis. In a greenhouse experiment the effects of N-modified lignite granulates (NLG) and composted biochar (BC) on the growth of spring wheat (Triticum aestivum) in a sandy, carbon-free substrate were compared. Additionally, the effect of different NLG application rates (5, 7.5, 11, 15, 28 t ha^?1) was investigated. Yields as well as nitrogen and water use efficiency of the soil-plant system were determined at the end of the experiment. Both organic amendments increased yields relative to control plants. An increase in yield, nitrogen and water use efficiency for NLG even at low application rates and a better growth performance compared to BC were observed. Present findings, therefore, indicate, that such granulates offer an alternative to existing organic soil amendments.     

Attempted definition by immunoblotting of the causes of reactivity in suspected false-positive sera in the Brucella ovis complement fixation test

Seventy-nine suspected false-positive sera, obtained over 1 year from routine submissions for Brucella ovis serological testing, were used in this study. These sera, which exhibited titres in the complement fixation test, but which because of their epidemiological history and their reactions in the enzyme-linked immunosorbent assay and gel diffusion test wereisuspected to be false positives, were further analysed by immunoblotting. In blots, using B. ovis antigens, rough lipopolysacchride was identified as the major, immuno-reactive bacterial component. Antibodies against this macromolecule were present in 46.8% of the suspected falsepositive sera.

In order to find out if rough lipopolysaccharides from other bacterial species could be the possible cause for the suspected false positivity, 23 sera with highest complement fixation titres were reacted in blots with cell extracts from Escherichia coli, Yersinia enterocolitica, Yersinia pseudotuberculosis, Bortedella bronchiseptica, Actinobacillus setninis, Catnpylobacter fetus fetus, Campylobacter jejuni, Mycobacterium paratuberculosis, Mycobacterium phlei, Corynebacterium pseudotuberculosis and pure lipopolysaccharides from Escherrichia coli and Salmonella typhimurium. Despite high frequencies of antibody reaction with proteins in most of these bacterial cell extracts, which reflect the presence of infections with these bacteria, immuno-staining in the rough lipopolysaccharide region was not observed.     

Effect of high temperature stress during ripening on the accumulation of key storage compounds among Japanese highly palatable rice cultivars

High temperature stress during ripening increases the frequency of chalky grains, resulting in a lower market value for rice (Oryza sativa L.). Changes in starch properties and the accumulation pattern of storage proteins are proposed to be related to the occurrence of chalky grains. This study investigated changes in the accumulation of key storage compounds in the grains of Japanese highly palatable rice cultivars, subjected to high temperature stress when grown in a growth chamber and the field. The 13 kDa prolamin content was significantly reduced in a highly heat-sensitive cultivar, Tsukushiroman, whereas the 13 kDa prolamin content was not affected in a heat-tolerant cultivar, Genkitsukushi, even in a high temperature chamber condition (31/26 °C day/night), when compared with the control chamber condition (26/21 °C day/night) for both genotypes. In addition, grains grown in field conditions revealed that severely chalky grains had less 13 kDa prolamin than perfect grains in all five genotypes. Changes in amylose content and the distribution of amylopectin chain lengths did not explain the difference in grain appearance both for chamber and field experiments. These results strongly suggest that physiological processes linked with the synthesis of 13 kDa prolamin are associated with grain appearance in Japanese highly palatable under high temperature stress.     

Insulin resistance selectively alters cell-surface glucose transporters but not their total protein expression in equine skeletal muscle

Background: Insulin resistance (IR) has been widely recognized in humans, and more recently in horses, but its underlying mechanisms are still not well understood. The translocation of glucose transporter 4 (GLUT4) to the cell surface is the limiting step for glucose uptake in insulin‐sensitive tissues. Although the downstream signaling pathways regulating GLUT translocation are not well defined, AS160 recently has emerged as a potential key component. In addition, the role of GLUT12, one of the most recently identified insulin‐sensitive GLUTs, during IR is unknown. Hypothesis/Objectives: We hypothesized that cell‐surface GLUT will be decreased in muscle by an AS160‐dependent pathway in horses with IR. Animals: Insulin‐sensitive (IS) or IR mares (n = 5/group). Methods: Muscle biopsies were performed in mares classified as IS or IR based on results of an insulin‐modified frequently sampled IV glucose tolerance test. By an exofacial bis‐mannose photolabeled method, we specifically quantified active cell‐surface GLUT4 and GLUT12 transporters. Total GLUT4 and GLUT12 and AS160 protein expression were measured by Western blots. Results: IR decreased basal cell‐surface GLUT4 expression (P= .027), but not GLUT12, by an AS160‐independent pathway, without affecting total GLUT4 and GLUT12 content. Cell‐surface GLUT4 was not further enhanced by insulin stimulation in either group. Conclusions and Clinical Importance: IR induced defects in the skeletal muscle glucose transport pathway by decreasing active cell‐surface GLUT4.     

荧光假单孢菌的生防遗传改良

综述了荧光假单孢菌生物防治方面的分子生物学研究进展，提出了通过遗传工程手段进一步改良的可行途径。