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Selected AbstractsA subpopulation of mesenchymal stromal cells with high osteogenic potentialJOURNAL OF CELLULAR AND MOLECULAR MEDICINE, Issue 8b 2009Hua Liu Abstract Current bone disease therapy with bone marrow-derived mesenchymal stromal cells (MSC) is hampered by low efficiency. Advanced allogeneic studies on well-established mouse genetic and disease models are hindered by difficulties in isolating murine MSC (mMSC). And mMSC prepared from different laboratories exhibit significant heterogeneity. Hence, this study aimed to identify and isolate a sub-population of mMSC at an early passage number with high osteogenic potential. Enrichment of mMSC was achieved by 1-hr silica incubation and negative selection. Approximately 96% of these cells synthesized osteocalcin after 28 days of osteogenic induction in vitro, and displayed a complete dynamic alteration of alkaline phosphatase (ALP) activity with increasing osteogenic maturation and strong mineralization. Moreover, the cells displayed uniform and stable surface molecular profile, long-term survival, fast proliferation in vitro with maintenance of normal karyotype and distinct immunological properties. CD73 was found to be expressed exclusively in osteogenesis but not in adipogenesis. These cells also retained high osteogenic potential upon allogeneic transplantation in an ectopic site by the detection of bone-specific ALP, osteopontin, osteocalcin and local mineralization as early as 12 days after implantation. Hence, these cells may provide a useful source for improving current strategies in bone regenerative therapy, and for characterizing markers defining the putative MSC population. [source] Clinician attitudes towards prescribing and implications for interventions in a multi-specialty group practiceJOURNAL OF EVALUATION IN CLINICAL PRACTICE, Issue 6 2008Robert J. Fortuna MD Abstract Background, Prescribing decisions are subject to a myriad of external forces, including patient requests for advertised medications. Although numerous factors influence prescribing, resources to support unbiased evidence-based prescribing are not widely available. Methods, To guide future interventions, we surveyed clinicians about influences on prescribing, awareness of pharmaceutical costs and attitudes towards computerized decision support. A 21-item survey was sent to 604 prescribing clinicians in a large multi-specialty group practice that employs a robust electronic medical record. Results, Surveys were returned from 405 clinicians (67%). Most respondents (87%) felt that direct-to-consumer (DTC) advertising prompts patients to request inappropriate medications, and more than one in five clinicians (22%) reported difficulty declining patients' requests for advertised medications. Providers with more clinical sessions per week reported greater difficulty. Although 93% of clinicians felt they have access to the information needed to guide prescribing, only about half (54%) reported they are aware of how much patients pay for prescription medications. Clinicians' awareness of medication costs varied considerably by specialty, with behavioural health clinicians being the most aware. The majority of providers (79%) stated that computerized prescribing alerts are a clinically useful source of information. Conclusions, Although the majority of clinicians reported that DTC advertising leads many patients to request medications that are inappropriate for their condition, a sizable proportion of clinicians reported difficulty declining these requests, and many are unaware of medication costs. Interventions to support prescribing decisions should provide the busiest clinicians with up-to-date, specialty-specific evidence and cost information. [source] Molted feathers from clay licks in Peru provide DNA for three large macaws (Ara ararauna, A. chloropterus, and A. macao)JOURNAL OF FIELD ORNITHOLOGY, Issue 2 2009Kara J. Gebhardt ABSTRACT Conservation genetic analyses of wildlife have increased greatly in the past 10 yr, yet genetic studies of parrots are rare because of difficulties associated with capturing them and obtaining samples. Recent studies have demonstrated that molted feathers can provide a useful source of DNA, but success rates have varied considerably among studies. Our objective was to determine if molted macaw feathers from Blue-and-yellow Macaws (Ara ararauna), Scarlet Macaws (A. macao), and Red-and-green Macaws (A. chloropterus) collected from rainforest geophagy sites called clay licks could provide a good source of DNA for population genetic studies. Specific objectives were to determine (1) how nuclear DNA microsatellite amplification success and genotyping error rates for plucked macaw feathers compared to those for molted feathers collected from clay licks in the Amazon rainforest, and (2) if feather size, feather condition, species, or extraction method affected microsatellite amplification success or genotyping error rates from molted feathers. Amplification success and error rates were calculated using duplicate analyses of four microsatellite loci. We found that plucked feathers were an excellent source of DNA, with significantly higher success rates (P < 0.0001) and lower error rates (P= 0.0002) than for molted feathers. However, relatively high success rates (75.6%) were obtained for molted feathers, with a genotyping error rate of 11.7%. For molted feathers, we had higher success rates and lower error rates for large feathers than small feathers and for feathers in good condition than feathers that were moldy and broken when collected. We also found that longer incubation times and lower elution volumes yielded the highest quality DNA when extracting with the Qiagen DNeasy tissue kit. Our study demonstrates that molted feathers can be a valuable source of genetic material even in the challenging conditions of tropical rainforests, and our results provide valuable information for maximizing DNA amplification success rates when working with shed feathers of parrots. SINOPSIS Los análisis genéticos para la conservación de la vida silvestre han crecido en gran escala durante los últimos 10 años, pero el análisis genético de los loros son raros por las dificultades asociados con su captura y obtención de muestras. Estudios recientes han demostrado que plumas mudadas podrían proveer una fuente útil de ADN, pero las tasas de éxito varían considerablemente entre estudios. Nuestro objetivo fue determinar si las plumas mudadas de Ara ararauna, A. macao y A. chloropterus colectadas en sitios de bosque húmedo donde estas aves consumen el suelo, llamados colpas, podrían proveer una fuente útil de ADN para estudios de la genética de las poblaciones. Los objetivos específicos fueron determinar (1) como comparan las tasas de éxito de la amplificación de los microsatélites del ADN nuclear y las tasas de error en el análisis del genotipo de plumas, entre plumas colectadas directamente de los guacamayos y plumas colectadas en colpas en el bosque Amazónico, y (2) si el tamaño de la pluma, su condición, la especie o el método de extracción afecta el éxito de la amplificación de los microsatélites o las tasas de error en el análisis del genotipo de las plumas mudadas. Las tasas de éxito de amplificación y error fueron calculados usando análisis duplicados de cuatro loci de microsatélites. Encontramos que plumas colectadas directamente de las aves son una fuente excelente de ADN, con tasas de éxito significativamente más altas (P < 0.0001), y con menores tasas de error (P= 0.0002) que las plumas mudadas. Sin embargo, tasas de éxito relativamente altas (75.6%) fueron obtenidos de plumas mudadas, con una tasa de error en el análisis del genotipo de 11.7%. Para plumas mudadas, tuvimos tasas de éxito más altas y tasas de error menores para plumas grandes que para plumas pequeñas y para plumas en buena condición que para plumas que estaban cubiertos con hongos y quebradas cuando fueron colectadas. También encontramos que mayores periodos de incubación y menores volúmenes de elución proveían el ADN de mayor calidad cuando se extraía el ADN usando el kit de tejido Quiagen DNeasy. Nuestro estudio demuestra que las plumas mudadas pueden ser una fuente valiosa de materia genética, hasta en las condiciones de los bosques húmedos tropicales. Nuestros resultados proveen información valiosa para maximizar las tasas de éxito de la amplificación del ADN cuando se analizan las plumas mudadas de los loros. [source] Exploring Equisetum arvense L., Equisetum ramosissimum L. and Equisetum telmateia L. as sources of natural antioxidantsPHYTOTHERAPY RESEARCH, Issue 4 2009Dubravka, tajner Abstract The antioxidant and scavenging activities of above ground parts of Equisetum arvense L., Equisetum ramosissimum L. and Equisetum telmateia L. phosphate buffer (pH 7) extracts were investigated. Activities of antioxidant enzymes (superoxide dismutase, catalase, guaiacol peroxidase and glutathione peroxidase), quantities of reduced glutathione, malonyldialdehyde, superoxide and hydroxyl radicals and flavonoid, soluble protein, chlorophyll a, b and carotenoid contents were determined. The total antioxidant capacity was determined by ferric reducing antioxidant power (FRAP) assay. The Equisetum telmateia extract demonstrated scavenging and antioxidant properties better than Equisetum ramosissimum and Equisetum arvense. The ESR signal of DMPO-OH radical adducts in the presence of Equisetum telmateia phosphate buffer (pH 7) extract was reduced by 98.9% indicating that Equisetum telmateia could be a useful source of antioxidants with huge scavenging ability. Copyright © 2008 John Wiley & Sons, Ltd. [source] Characterisation of a P140K mutant O6 -methylguanine-DNA-methyltransferase (MGMT)-expressing transgenic mouse line with drug-selectable bone marrowTHE JOURNAL OF GENE MEDICINE, Issue 9 2006Belinda A. Kramer Abstract Background Gene transfer of the P140K mutant of O6 -methylguanine-DNA-methyltransferase (MGMT(P140K)) into hematopoietic stem cells (HSC) provides a mechanism for drug resistance and the selective expansion of gene-modified cells in vivo. Possible clinical applications for this strategy include chemoprotection to allow dose escalation of alkylating chemotherapy, or combining MGMT(P140K) expression with a therapeutic gene in the treatment of genetic diseases. Our aim is to use MGMT(P140K)-driven in vivo selection to develop allogeneic micro-transplantation protocols that rely on post-engraftment selection to overcome the requirement for highly toxic pre-transplant conditioning, and to establish and maintain predictable levels of donor/recipient chimerism. Methods Using stably transfected murine embryonic stem (ES) cells, we have generated a C57BL/6 transgenic mouse line with expression of MGMT(P140K) within the hematopoietic compartment for use as a standard source of donor HSC in such models. Functional characterisation of transgene expression was carried out in chemotherapy-treated transgenic mice and in allogeneic recipients of transgenic HSC. Results Expression of the transgene provided chemoprotection and allowed in vivo selection of MGMT(P140K)-expressing cells in transgenic mice after exposure to O6 -benzylguanine (BG) and N,N,-bis(2-chloroethyl)- N -nitrosourea (BCNU). In an allogeneic transplant experiment in which transgenic HSC were engrafted into 129 strain recipients following low intensity conditioning (Busulfan, anti-CD8, anti-CD40Ligand), MGMT(P140K)-expressing cells could be selected using chemotherapy. Conclusions This MGMT(P140K) transgenic mouse line provides a useful source of drug-selectable donor cells for the development of non-myeloablative allogeneic transplant models in which variation in transplant conditioning elements can be investigated independently of gene transfer efficiency. Copyright © 2006 John Wiley & Sons, Ltd. [source] Phenological description of natural vegetation in southern Africa using remotely-sensed vegetation dataAPPLIED VEGETATION SCIENCE, Issue 1 2004David Hoare Abstract. Various attempts have been made to describe and map the vegetation of southern Africa with recent efforts having an increasingly ecologi cal context. Vegetation classification is usually based on vegetation physiognomy and floristic composition, but phenology is useful source of information which is rarely used, although it can contribute functional information on ecosystems. The objectives of this study were to identify a suite of variables derived from time-series NDVI data that best describe the phenological phenomena of vegetation in southern Africa and, secondly, to assess a classification of pixels of the study area based on NDVI variables using a preexisting map of the biomes that was delimited on the basis of life forms and climate. A number of variables were derived from the satellite data for describing phenological phenomena, which were analysed by multivariate techniques to determine which variables best explained the variation in the satellite data. This set of variables was used to produce a phenological classification of the vegetation of southern Africa, the results of which are discussed in relation to their concordance with the existing biome boundaries. [source] Identifications of expressed sequence tags from Pacific threadfin (Polydactylus sexfilis) skeletal muscle cDNA libraryAQUACULTURE RESEARCH, Issue 4 2010Shizu Watanabe Abstract Pacific threadfin (Polydactylus sexfilis), locally known as Moi, is a desirable fish for aquaculture and recreational fishing. To understand the basic mechanism of muscle formation and its impacts on flesh quality, we established a cDNA library using mRNA of the skeletal muscle tissue from fingerlings. The library size was 1.1 × 108 plaque forming units mg,1 and the percentage of recombinant clones was >81%. A pilot sequencing project from 181 clones identified 129 useful expressed sequence tags (ESTs), of which 90 ESTs exhibited significant homology to known genes and 39 ESTs have low homologies to unknown genes by blast algorithm. The most abundant EST from the pilot sequence data is nikotinamide riboside kinase 2 (59 times), followed by 60S ribosomal protein L24 (12 times) and ribosomal protein L8 (5 times). Fourteen novel genes were retrieved from the sequenced clones and subjected to gene ontology annotation. Four mRNA sequences were identified as significant regulators of transcription, including Not2p, Tsc22 domain family 2, LIM domain binding factor 3 and mesenchyme homeobox 2. These results suggest that the muscle cDNA library is an useful source for identifying EST sequences of Pacific threadfin. [source] Using private demand studies to calculate socially optimal vaccine subsidies in developing countriesJOURNAL OF POLICY ANALYSIS AND MANAGEMENT, Issue 1 2009Joseph Cook Although it is well known that vaccines against many infectious diseases confer positive economic externalities via indirect protection, analysts have typically ignored possible herd protection effects in policy analyses of vaccination programs. Despite a growing literature on the economic theory of vaccine externalities and several innovative mathematical modeling approaches, there have been almost no empirical applications. The first objective of the paper is to develop a transparent, accessible economic framework for assessing the private and social economic benefits of vaccination. We also describe how stated preference studies (for example, contingent valuation and choice modeling) can be useful sources of economic data for this analytic framework. We demonstrate socially optimal policies using a graphical approach, starting with a standard textbook depiction of Pigouvian subsidies applied to herd protection from vaccination programs. We also describe nonstandard depictions that highlight some counterintuitive implications of herd protection that we feel are not commonly understood in the applied policy literature. We illustrate the approach using economic and epidemiological data from two neighborhoods in Kolkata, India. We use recently published epidemiological data on the indirect effects of cholera vaccination in Matlab, Bangladesh (Ali et al., 2005) for fitting a simple mathematical model of how protection changes with vaccine coverage. We use new data on costs and private demand for cholera vaccines in Kolkata, India, and approximate the optimal Pigouvian subsidy. We find that if the optimal subsidy is unknown, selling vaccines at full marginal cost may, under some circumstances, be a preferable second-best option to providing them for free. © 2009 by the Association for Public Policy Analysis and Management. [source] Evaluation of Gossypium species for resistance to cotton leaf curl Burewala virusANNALS OF APPLIED BIOLOGY, Issue 1 2010K.P. Akhtar Cotton leaf curl disease (CLCuD), caused by cotton leaf curl Burewala virus (CLCuBV), has emerged as a major threat to cotton production in Pakistan. Resistance to CLCuBV was evaluated in cultivated and wild cotton genotypes representing six Gossypium species by visual symptom scoring and virus assessment using PCR tests. Considerable variation in responses was observed when using whitefly and graft transmission to inoculate Gossypium genotypes with CLCuBV in field and greenhouse experiments. Under field evaluation, all cultivated genotypes of Gossypium hirsutum and three genotypes of G. barbadense were susceptible. Eleven genotypes that represented six wild and cultivated Gossypium species were considered to be highly resistant as they were free from infection. Similar results were obtained when these genotypes were tested using whitefly transmission. To verify these findings, 132 cultivated and wild genotypes were tested by graft inoculation. All G. hirsutum genotypes (116 cultivated, 1 wild, 1 transgenic Coker-312 and 1 non-transgenic Coker-312), three G. barbadense genotypes and one G. thurberi genotype were highly susceptible and exhibited symptoms 9,12 days after grafting. Four genotypes of G. arboreum and one genotype of G. anomalum did not express symptoms but had a detectable level of virus. One genotype of G. herbaceum and three wild genotypes of G. hirsutum showed mild symptoms (severity indexes of 1,2) and exhibited delayed disease development. These genotypes were classified as moderately resistant to resistant. Resistant genotypes that were identified in this study will be useful sources for exploitation of breeding programmes aimed at developing CLCuBV-resistant varieties and increasing genetic diversity. [source] Responses of genotypes from species of Trifolium, Ornithopus, Biserrula and Hedysarum to a highly virulent race of Phytophthora clandestina and new sources of resistanceANNALS OF APPLIED BIOLOGY, Issue 2 2009H. Li Abstract Thirty-six genotypes, including 15 cultivars and 10 breeding lines of Trifolium subterraneum, a single genotype of each of seven other species of Trifolium (viz. Trifolium dasyurum, Trifolium glanduliferum, Trifolium incarnatum, Trifolium michelanium, Trifolium purpureum, Trifolium spumosum and Trifolium vesiculosum), Biserrula pelecinus, Hedysarum coronarium, Ornithopus compressus and Ornithopus sativus were screened under controlled environmental conditions for resistance to root disease caused by the most pathogenic race of Phytophthora clandestina occurring in Australia, namely race 177. This is the first time any of these genera/species other than T.subterraneum has ever been screened for its response to P. clandestina. The root disease caused by P.clandestina is the first report of susceptibility to this pathogen for the seven other species of Trifolium and also for B.pelecinus, H.coronarium and O.sativus. Within T.subterraneum, a very high level of resistance was identified in cvs Denmark, Junee and Meteora [scores ,1.5 (0,5 scale where 0 = no disease) across two separate screening tests] and in the breeding lines SL027 and SM023 (scores ,1.3 across two separate screening tests). Six of the seven other species of Trifolium (viz. T.dasyurum, T.glanduliferum, T.incarnatum, T.michelanium, T.purpureum and T.spumosum) showed a high level of resistance (scores ,0.8 across two separate screening tests), while T.vesiculosum showed a disease score of ,1.2 across both screening tests. O.compressus showed no disease in either test, and O.sativus showed a disease score of ,0.7 across both screening tests. H.coronarium was susceptible with a disease score of ,2.8 across two separate screening tests, while B.pelecinus was highly susceptible with disease scores of 3.5 and 4.6 in these tests. The high levels of resistance identified against P.clandestina are useful sources of resistance that can be exploited commercially, either directly to minimise damage from this disease or as parents in breeding programs to develop cultivars within the genera/species tested with improved resistance to this highly pathogenic race of P.clandestina. [source] Tips and tricks for writing a manuscriptACTA OPHTHALMOLOGICA, Issue 2009B DAMATO Purpose The aims of this presentation are to highlight some pearls and pitfalls in writing scientific articles. Methods It is not possible to write a good manuscript unless you have a good message to share. If you are reporting research results this means that you will need to have conducted the research properly, with good statistics, measures to avoid bias, complete data and, of course, an important hypothesis to test. If possible, expert advice should be obtained before the study is started so as to ensure that the trial design is appropriate and that the statistics are correct. Results The key to writing a good manuscript is to divide the paper into sections and to sub-divide each section into components, making sure that the sequence of ideas is in the correct order. The internet is full of good advice on how to write a good manuscript. This information be summarized in this presentation, which will also guide participants to useful sources of information. Conclusion Writing a manuscript is not difficult and should be a pleasurable and rewarding experience as long as one follows a few simple rules, which will be discussed in this talk. [source] | ||||||||||||||||