Comparison of in vitro regeneration efficiency of leaf explants in response to different cytokinins and assessment of genetic uniformity of regenerated plants of Solanum surattense Burm.f.

An efficient, genetically stable and rapid regeneration system via multiple shoot formation was developed for an endangered medicinal herb Solanum surattense. Leaves were cultured on MS medium supplemented with different concentration of cytokinins; 6-benzylaminopurine (BAP), kinetin (Kn), thiadiazuron (TDZ), zeatin and inorganic phosphate (iP) alone or in combinations. Among five cytokinins used, TDZ (0.1 mg/l) gave the maximum regeneration response (35 shoot buds per explant), with 100% regeneration efficiency. Comparative regeneration efficiency of cytokinins was in the following order: TDZ > zeatin > iP > BAP > Kn and the comparative ratio was 6:4:3:2:1. Highestfrequency of adventitious shoot bud induction (54 shoot buds per explant) was achieved on combination of TDZ (0.1 mg/l) and BAP (1 mg/l). Combinations of cytokinins were more effective for shoot bud regeneration as compared to cytokinin alone. Best root formation was observed on Murashige and Skoog (MS) medium supplemented with 1 mg/l indole-3-acetic acid (IBA). The rooted plantlets were hardened gradually and resulted in a production of more than 80% plantlets. Theefficiency of auxins for root organogenesis was in the following order: IBA > IAA > NAA > PAA. Genetic stability of regenerated plants was analyzed using random amplified polymorphic DNA (RAPD) markers.Keywords: Solanum surattense, adventitious shoot buds, genetic fidelity, random amplified polymorphic DNA, thiadiazuro

Analysis of the potential of cancer cell lines to release tissue factor-containing microvesicles: correlation with tissue factor and PAR2 expression

BackgroundDespite the association of cancer-derived circulating tissue factor (TF)-containing microvesicles and hypercoagulable state, correlations with the incidence of thrombosis remain unclear.MethodsIn this study the upregulation of TF release upon activation of various cancer cell lines, and the correlation with TF and PAR2 expression and/or activity was examined. Microvesicle release was induced by PAR2 activation in seventeen cell lines and released microvesicle density, microvesicle-associated TF activity, and phoshpatidylserine-mediated activity were measured. The time-course for TF release was monitored over 90 min in each cell line. In addition, TF mRNA expression, cellular TF protein and cell-surface TF activities were quantified. Moreover, the relative expression of PAR2 mRNA and cellular protein were analysed. Any correlations between the above parameters were examined by determining the Pearson’s correlation coefficients.ResultsTF release as microvesicles peaked between 30–60 min post-activation in the majority of cell lines tested. The magnitude of the maximal TF release positively correlated with TF mRNA (c = 0.717; p

The influence of the ectomycorrhizal fungus Rhizopogon subareolatus on growth and nutrient element localisation in two varieties of Douglas fir (Pseudotsuga menziesii var. menziesii and var. glauca) in response to manganese stress

Acidification of forest ecosystems leads to increased plant availability of the micronutrient manganese (Mn), which is toxic when taken up in excess. To investigate whether ectomycorrhizas protect against excessive Mn by improving plant growth and nutrition or by retention of excess Mn in the hyphal mantle, seedlings of two populations of Douglas fir (Pseudotsuga menziesii), two varieties, one being menziesii (DFM) and the other being glauca (DFG), were inoculated with the ectomycorrhizal fungus Rhizopogon subareolatus in sand cultures. Five months after inoculation, half of the inoculated and non-inoculated seedlings were exposed to excess Mn in the nutrient solution for further 5 months. At the end of this period, plant productivity, nutrient concentrations, Mn uptake and subcellular compartmentalisation were evaluated. Non-inoculated, non-stressed DFM plants produced about 2.5 times more biomass than similarly treated DFG. Excess Mn in the nutrient solution led to high accumulation of Mn in needles and roots but only to marginal loss in biomass. Colonisation with R. subareolatus slightly suppressed DFM growth but strongly reduced that of DFG (−50%) despite positive effects of mycorrhizas on plant phosphorus nutrition. Growth reductions of inoculated Douglas fir seedlings were unexpected since the degree of mycorrhization was not high, i.e. ca. 30% in DFM and 8% in DFG. Accumulation of high Mn was not prevented in inoculated seedlings. The hyphal mantle of mycorrhizal root tips accumulated divalent cations such as Ca, but not Mn, thus not providing a barrier against excessive Mn uptake into the plants associated with R. subareolatus

Economic language and economy change: with implications for cyber-physical systems

The implementation of cyber-physical and similar systems depends on prevailing social and economic conditions. It is here argued that, if the effect of these technologies is to be benign, the current neo-liberal economy must change to a radically more cooperative model. In this paper, economy change means a thorough change to a qualitatively different kind of economy. It is contrasted with economic change, which is the kind of minor change usually considered in mainstream discourse. The importance of language is emphasised, including that of techno-optimism and that of economic conservatism. Problems of injustice, strife, and ecological overload cannot be solved by conventional growth together with technical efficiency gains. Rather, a change is advocated from economics-as-usual to a broader concept, oikonomia (root-household management), which takes into account all that contributes to a good life, including what cannot be represented quantitatively. Some elements of such a broader economy (work; basic income; asset and income limits) are discussed. It is argued that the benefits of technology can be enhanced and the ills reduced in such an economy. This is discussed in the case of cyber-physical systems under the headings employment, security, standards and oligopoly, and energy efficiency. The paper concludes that such systems, and similar technological developments, cannot resolve the problems of sustainability within an economy-as-usual model. If, however, there is the will to create a cooperative and sustainable economy, technology can contribute significantly to the resolution of present problems

Agronomic Management of Indigenous Mycorrhizas

Many of the advantages conferred to plants by arbuscular mycorrhiza (AM) are associated to the ability of AM plants to explore a greater volume of soil through the extraradical mycelium. Sieverding (1991) estimates that for each centimetre of colonized root there is an increase of 15 cm3 on the volume of soil explored, this value can increase to 200 cm3 depending on the circumstances. Due to the enhancement of the volume of soil explored and the ability of the extraradical mycelium to absorb and translocate nutrients to the plant, one of the most obvious and important advantages resulting from mycorrhization is the uptake of nutrients. Among of which the ones that have immobilized forms in soil, such as P, assume particular significance. Besides this, many other benefits are recognized for AM plants (Gupta et al, 2000): water stress alleviation (Augé, 2004; Cho et al, 2006), protection from root pathogens (Graham, 2001), tolerance to toxic heavy metals and phytoremediation (Audet and Charest, 2006; Göhre and Paszkowski, 2006), tolerance to adverse conditions such as very high or low temperature, high salinity (Sannazzaro et al, 2006), high or low pH (Yano and Takaki, 2005) or better performance during transplantation shock (Subhan et al, 1998). The extraradical hyphae also stabilize soil aggregates by both enmeshing soil particles (Miller e Jastrow, 1992) and producing a glycoprotein, golmalin, which may act as a glue-like substance to adhere soil particles together (Wright and Upadhyaya, 1998). Despite the ubiquous distribution of mycorrhizal fungi (Smith and Read, 2000) and only a relative specificity between host plants and fungal isolates (McGonigle and Fitter, 1990), the obligate nature of the symbiosis implies the establishment of a plant propagation system, either under greenhouse conditions or in vitro laboratory propagation. These techniques result in high inoculum production costs, which still remains a serious problem since they are not competitive with production costs of phosphorus fertilizer. Even if farmers understand the significance of sustainable agricultural systems, the reduction of phosphorus inputs by using AM fungal inocula alone cannot be justified except, perhaps, in the case of high value crops (Saioto and Marumoto, 2002). Nurseries, high income horticulture farmers and no-agricultural application such as rehabilitation of degraded or devegetated landscapes are examples of areas where the use of commercial inoculum is current. Another serious problem is quality of commercial available products concerning guarantee of phatogene free content, storage conditions, most effective application methods and what types to use. Besides the information provided by suppliers about its inoculum can be deceiving, as from the usually referred total counts, only a fraction may be effective for a particular plant or in specific soil conditions. Gianinazzi and Vosátka (2004) assume that progress should be made towards registration procedures that stimulate the development of the mycorrhizal industry. Some on-farm inoculum production and application methods have been studied, allowing farmers to produce locally adapted isolates and generate a taxonomically diverse inoculum (Mohandas et al, 2004; Douds et al, 2005). However the inocula produced this way are not readily processed for mechanical application to the fields, being an obstacle to the utilization in large scale agriculture, especially row crops, moreover it would represent an additional mechanical operation with the corresponding economic and soil compaction costs. It is well recognized that inoculation of AM fungi has a potential significance in not only sustainable crop production, but also environmental conservation. However, the status quo of inoculation is far from practical technology that can be widely used in the field. Together a further basic understanding of the biology and diversity of AM fungi is needed (Abbott at al, 1995; Saito and Marumoto, 2002). Advances in ecology during the past decade have led to a much more detailed understanding of the potential negative consequences of species introductions and the potential for negative ecological consequences of invasions by mycorrhizal fungi is poorly understood. Schwartz et al, (2006) recommend that a careful assessment documenting the need for inoculation, and the likelihood of success, should be conducted prior to inoculation because inoculations are not universally beneficial. Agricultural practices such as crop rotation, tillage, weed control and fertilizer apllication all produce changes in the chemical, physical and biological soil variables and affect the ecological niches available for occupancy by the soil biota, influencing in different ways the symbiosis performance and consequently the inoculum development, shaping changes and upset balance of native populations. The molecular biology tools developed in the latest years have been very important for our perception of these changes, ensuing awareness of management choice implications in AM development. In this context, for extensive farming systems and regarding environmental and economic costs, the identification of agronomic management practices that allow controlled manipulation of the fungal community and capitalization of AM mutualistic effect making use of local inoculum, seem to be a wise option for mycorrhiza promotion and development of sustainable crop production

Community capacity to acquire, assess, adapt, and apply research evidence: a survey of Ontario's HIV/AIDS sector

<p>Abstract</p> <p>Background</p> <p>Community-based organizations (CBOs) are important stakeholders in health systems and are increasingly called upon to use research evidence to inform their advocacy, program planning, and service delivery. To better support CBOs to find and use research evidence, we sought to assess the capacity of CBOs in the HIV/AIDS sector to acquire, assess, adapt, and apply research evidence in their work.</p> <p>Methods</p> <p>We invited executive directors of HIV/AIDS CBOs in Ontario, Canada (n = 51) to complete the Canadian Health Services Research Foundation's "Is Research Working for You?" survey.</p> <p>Findings</p> <p>Based on responses from 25 organizations that collectively provide services to approximately 32,000 clients per year with 290 full-time equivalent staff, we found organizational capacity to acquire, assess, adapt, and apply research evidence to be low. CBO strengths include supporting a culture that rewards flexibility and quality improvement, exchanging information within their organization, and ensuring that their decision-making processes have a place for research. However, CBO Executive Directors indicated that they lacked the skills, time, resources, incentives, and links with experts to acquire research, assess its quality and reliability, and summarize it in a user-friendly way.</p> <p>Conclusion</p> <p>Given the limited capacity to find and use research evidence, we recommend a capacity-building strategy for HIV/AIDS CBOs that focuses on providing the tools, resources, and skills needed to more consistently acquire, assess, adapt, and apply research evidence. Such a strategy may be appropriate in other sectors and jurisdictions as well given that CBO Executive Directors in the HIV/AIDS sector in Ontario report low capacity despite being in the enviable position of having stable government infrastructure in place to support them, benefiting from long-standing investment in capacity building, and being part of an active provincial network. CBOs in other sectors and jurisdictions that have fewer supports may have comparable or lower capacity. Future research should examine a larger sample of CBO Executive Directors from a range of sectors and jurisdictions.</p

Ratio of the Isolated Photon Cross Sections at \sqrt{s} = 630 and 1800 GeV

The inclusive cross section for production of isolated photons has been measured in \pbarp collisions at $\sqrt{s} = 630$ GeV with the \D0 detector at the Fermilab Tevatron Collider. The photons span a transverse energy ($E_T$) range from 7-49 GeV and have pseudorapidity $|\eta| < 2.5$. This measurement is combined with to previous \D0 result at $\sqrt{s} = 1800$ GeV to form a ratio of the cross sections. Comparison of next-to-leading order QCD with the measured cross section at 630 GeV and ratio of cross sections show satisfactory agreement in most of the $E_T$ range.Comment: 7 pages. Published in Phys. Rev. Lett. 87, 251805, (2001

Large vessel vasculitis

Takayasu arteritis is a chronic granulomatous disease of the aorta and its major branches that usually affects women during the second and third decades of life, but it has been reported in young children. This review details the clinical, pathological and radiological features, differential diagnoses and management of the condition, focusing chiefly on the disease in children. The recent definition of Takayasu arteritis is discussed. The condition should be considered in patients with unexplained arterial hypertension or unexplained inflammatory syndromes without signs of localization. Since the disease may be life-threatening and progressive, early recognition is necessary to initiate appropriate therapy. Patients with persistent ischaemic symptoms including hypertension might benefit from revascularization procedures