275 research outputs found

    A possible mechanism of histamine release

    Get PDF
    In the introduction a brief historical review is given of the importance of histamine as the agent responsible for the development of the signs and symptoms of anaphylactic shock in several animal species. Various aspects of histamine metabolism are considered, including the origin, the intracellular distribution and the rate of detoxication of this substance by histaminase in normal and sensitive individuals, and the kinetics of its release during shock. A possible connection is suggested between the metabolic function of mitochondria and protein metabolism on the one hand and the metabolism of histamine on the other. This scheme is correlated with the ability of intracellular particles to synthesize high energy phosphate bonds. In the experimental section it is shown that histamine-liberating drugs can release histamine from tissue homogenates, but that this action cannot be associated with changes in the activity of intracellular proteolytic enzymes. Evidence is given that three powerful histamine liberators react v/ith adenosine triphosphate and several other phosphates at extremely low concentrations, and that intravenous ATP can modify, or even annul the action of these drugs in the intact animal. A mechanism of histamine release depending on the metabolic activity of the mitochondria is suggested in the discussion. This attempts to explain the explosive nature of histamine release both during anaphylaxis and during the action of the liberating drugs. It also offers a possible explanation for the appearance of smooth muscle stimulating polypeptides.<p

    THREE-DIMENSIONAL ASSESSMENT OF ON WATER ROWING TECHNIQUE: A METHODOLOGICAL STUDY

    Get PDF
    The analysis of rowing technique in training or competitive environments has been a challenge to biomechanists for some time now. Typically, two-dimensional assessments are carried out with fixed cameras mounted on-land next to a rowing course (Hay 1993) or by handheld cameras from an accompanying boat. Three-dimensional technique analysis were only presented for athletes rowing on an ergometer in a laboratory environment (Hofmijster et al. 2007). The purpose of this study was to develop and validate a system for three-dimensional kinematic analyses of on water rowing

    Digestibility of Dried Sweet Potatoes by Steers and Lambs

    Get PDF
    The Oklahoma Agricultural Experiment Station periodically issues revisions to its publications. The most current edition is made available. For access to an earlier edition, if available for this title, please contact the Oklahoma State University Library Archives by email at [email protected] or by phone at 405-744-6311

    TILLING to detect induced mutations in soybean

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Soybean (<it>Glycine max </it>L. Merr.) is an important nitrogen-fixing crop that provides much of the world's protein and oil. However, the available tools for investigation of soybean gene function are limited. Nevertheless, chemical mutagenesis can be applied to soybean followed by screening for mutations in a target of interest using a strategy known as Targeting Induced Local Lesions IN Genomes (TILLING). We have applied TILLING to four mutagenized soybean populations, three of which were treated with ethyl methanesulfonate (EMS) and one with N-nitroso-N-methylurea (NMU).</p> <p>Results</p> <p>We screened seven targets in each population and discovered a total of 116 induced mutations. The NMU-treated population and one EMS mutagenized population had similar mutation density (~1/140 kb), while another EMS population had a mutation density of ~1/250 kb. The remaining population had a mutation density of ~1/550 kb. Because of soybean's polyploid history, PCR amplification of multiple targets could impede mutation discovery. Indeed, one set of primers tested in this study amplified more than a single target and produced low quality data. To address this problem, we removed an extraneous target by pretreating genomic DNA with a restriction enzyme. Digestion of the template eliminated amplification of the extraneous target and allowed the identification of four additional mutant alleles compared to untreated template.</p> <p>Conclusion</p> <p>The development of four independent populations with considerable mutation density, together with an additional method for screening closely related targets, indicates that soybean is a suitable organism for high-throughput mutation discovery even with its extensively duplicated genome.</p

    An international comparison of Retinopathy of Prematurity grading performance within the Benefits of Oxygen Saturation Targeting (BOOST) II trials. International variation in ROP grading.

    Get PDF
    PurposeTo investigate whether the observed international differences in retinopathy of prematurity (ROP) treatment rates within the Benefits of Oxygen Saturation Targeting (BOOST) II trials might have been caused by international variation in ROP disease grading.MethodsGroups of BOOST II trial ophthalmologists in UK, Australia, and New Zealand (ANZ), and an international reference group (INT) used a web based system to grade a selection of RetCam images of ROP acquired during the BOOST II UK trial. Rates of decisions to treat, plus disease grading, ROP stage grading, ROP zone grading, inter-observer variation within groups and intra-observer variation within groups were measured.ResultsForty-two eye examinations were graded. UK ophthalmologists diagnosed treat-requiring ROP more frequently than ANZ ophthalmologists, 13.9 (3.49) compared to 9.4 (4.46) eye examinations, P=0.038. UK ophthalmologists diagnosed plus disease more frequently than ANZ ophthalmologists, 14.1 (6.23) compared to 8.5 (3.24) eye examinations, P=0.021. ANZ ophthalmologists diagnosed stage 2 ROP more frequently than UK ophthalmologists, 20.2 (5.8) compared to 12.7 (7.1) eye examinations, P=0.026. There were no other significant differences in the grading of ROP stage or zone. Inter-observer variation was higher within the UK group than within the ANZ group. Intra-observer variation was low in both groups.ConclusionsWe have found evidence of international variation in the diagnosis of treatment-requiring ROP. Improved standardisation of the diagnosis of treatment-requiring ROP is required. Measures might include improved training in the grading of ROP, using an international approach, and further development of ROP image analysis software.Eye advance online publication, 28 July 2017; doi:10.1038/eye.2017.150

    Long term follow up of high risk children: who, why and how?

    Get PDF
    Background: Most babies are born healthy and grow and develop normally through childhood. There are, however, clearly identifiable high-risk groups of survivors, such as those born preterm or with ill-health, who are destined to have higher than expected rates of health or developmental problems, and for whom more structured and specialised follow-up programs are warranted. Discussion This paper presents the results of a two-day workshop held in Melbourne, Australia, to discuss neonatal populations in need of more structured follow-up and why, in addition to how, such a follow-up programme might be structured. Issues discussed included the ages of follow-up, and the personnel and assessment tools that might be required. Challenges for translating results into both clinical practice and research were identified. Further issues covered included information sharing, best practice for families and research gaps. Summary A substantial minority of high-risk children has long-term medical, developmental and psychological adverse outcomes and will consume extensive health and education services as they grow older. Early intervention to prevent adverse outcomes and the effective integration of services once problems are identified may reduce the prevalence and severity of certain outcomes, and will contribute to an efficient and effective use of health resources. The shared long-term goal for families and professionals is to work toward ensuring that high risk children maximise their potential and become productive and valued members of society. Electronic supplementary material The online version of this article (doi:10.1186/1471-2431-14-279) contains supplementary material, which is available to authorized users

    Developing a digital intervention for cancer survivors: an evidence-, theory- and person-based approach

    Get PDF
    This paper illustrates a rigorous approach to developing digital interventions using an evidence-, theory- and person-based approach. Intervention planning included a rapid scoping review which identified cancer survivors’ needs, including barriers and facilitators to intervention success. Review evidence (N=49 papers) informed the intervention’s Guiding Principles, theory-based behavioural analysis and logic model. The intervention was optimised based on feedback on a prototype intervention through interviews (N=96) with cancer survivors and focus groups with NHS staff and cancer charity workers (N=31). Interviews with cancer survivors highlighted barriers to engagement, such as concerns about physical activity worsening fatigue. Focus groups highlighted concerns about support appointment length and how to support distressed participants. Feedback informed intervention modifications, to maximise acceptability, feasibility and likelihood of behaviour change. Our systematic method for understanding user views enabled us to anticipate and address important barriers to engagement. This methodology may be useful to others developing digital interventions
    • …
    corecore