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Appropriate Techniques (appropriate + techniques)
Selected AbstractsORIGINAL INVESTIGATIONS: Potential Faces of Patent Foramen Ovale (PFO PFO)ECHOCARDIOGRAPHY, Issue 8 2010F.R.C.P., Tasneem Z Naqvi M.D. Background: Patent foramen ovale (PFO) is diagnosed on echocardiography by saline contrast study with or without color Doppler evidence of shunting. PFO is benign except when it causes embolic events. Methods and Results: In this report, we describe unique additional manifestations related to the diagnosis and presentation of PFO. These include demonstration of PFO during the release phase of "sigh" on the ventilator in the operating room, use of a separate venipuncture to allow preparation of blood-saline-air mixture after multiple failed saline bubble injections, resting and stress hypoxemia related to left to right shunting across a PFO in the absence of pulmonary hypertension, presentation of quadriperesis secondary to an embolic event from a PFO and development of a thrombus on the left atrial aspect of PFO in a patient with atrial fibrillation, and on the right atrial aspect of PFO in a patient who had undergone repair of a flail mitral valve. Finally, in one patient with end-stage renal disease, aortic valve endocarditis and periaortic abscess, PFO acted as a vent valve relieving right atrial pressure following development of aortoatrial fistula. Conclusion: PFO diagnosis can be elusive if appropriate techniques are not used during saline contrast administration. PFO can present as hypoxemia in the absence of pulmonary hypertension, can be a rare cause of quadriperesis, and can be associated with thrombus formation on either side of interatrial septum. Finally, PFO presence can be lifesaving in those with sudden increase in right atrial pressure such as with aortoatrial fistula. (Echocardiography 2010;27:897-907) [source] Response of small rodents to manipulations of vegetation height in agro-ecosystemsINTEGRATIVE ZOOLOGY (ELECTRONIC), Issue 1 2008Jens JACOB Abstract Some small mammal populations require human interference to conserve rare or threatened species or to minimize adverse effects in plant production. Without a thorough understanding about how small rodents behave in their environment and consideration of how they react to management efforts, management will not be optimal. Social behavior, spatial and temporal activity patterns, predator avoidance and other behavioral responses can affect pest rodent management. Some of these behavioral patterns and their causes have been well studied. However, their impact on pest rodent management, especially for novel management approaches, is not always clear. Habitat manipulation occurs necessarily through land use and intentionally to reduce shelter and food availability and to increase predation pressure on rodents. Rodents often respond to decreased vegetation height with reduced movements and increased risk sensitivity in their feeding behavior. This seems to result mainly from an elevated perceived predation risk. Behavioral responses may lessen the efficacy of the management because the desired effects of predators might be mediated. It remains largely unknown to what extent such responses can compensate at the population level for the expected consequences of habitat manipulation and how population size and crop damage are affected. It is advantageous to understand how target and non-target species react to habitat manipulation to maximize the management effects by appropriate techniques, timing and spatial scale without causing unwanted effects at the system level. [source] Foreign body in the apical portion of a root canal in a tooth with an immature apex: a case reportINTERNATIONAL ENDODONTIC JOURNAL, Issue 10 2008A. R. Prabhakar Abstract Aim, To describe the successful retrieval of a foreign object located in the apical portion of an immature root canal by simple orthograde techniques, avoiding the need for surgery or intentional reimplantation. Summary, A radio-opaque foreign object lodged in the apical portion of an immature root canal was discovered on radiographic examination of a patient with a complicated crown fracture. Attempts to retrieve it resulted in displacement into the periapical area. Eventually, the object was retrieved by a simple technique, followed by successful apexification, root canal filling and jacket crown placement. Key learning points ,,Foreign bodies in root canals should be carefully evaluated to determine their nature, position, size and the degree of difficulty that may be encountered during retrieval. ,,Patience, care and appropriate techniques may be helpful in retrieving foreign bodies and avoiding periapical surgery. ,,Complicated crown fractures should be managed promptly, and prolonged open drainage avoided in children if the risks of foreign body impaction are to be minimized. [source] Modelling current trends in Northern Hemisphere temperaturesINTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 7 2006Terence C. Mills Abstract Fitting a trend is of interest in many disciplines, but it is of particular importance in climatology, where estimating the current and recent trend in temperature is thought to provide a major indication of the presence of global warming. A range of ad hoc methods of trend fitting have been proposed, with little consensus as to the most appropriate techniques to use. The aim of this paper is to consider a range of trend extraction techniques, none of which require ,padding' out the series beyond the end of the available observations, and to use these to estimate the trend of annual mean Northern Hemisphere (NH) temperatures. A comparison of the trends estimated by these methods thus provides a robust indication of the likely range of current trend temperature increases and hence inform, in a timely quantitative fashion, arguments based on global temperature data concerning the nature and extent of global warming and climate change. For the complete sample 1856,2003, the trend is characterised as having long waves about an underlying increasing level. Since around 1970, all techniques display a pronounced warming trend. However, they also provide a range of trend functions so that extrapolation far into the future would be a hazardous exercise. Copyright © 2006 Royal Meteorological Society. [source] Mesenchymal stem cell interaction with a non-woven hyaluronan-based scaffold suitable for tissue repairJOURNAL OF ANATOMY, Issue 5 2008G. Pasquinelli Summary The fabrication of biodegradable 3-D scaffolds enriched with multipotent stem cells seems to be a promising strategy for the repair of irreversibly injured tissues. The fine mechanisms of the interaction of rat mesenchymal stem cells (rMSCs) with a hyaluronan-based scaffold, i.e. HYAFF®11, were investigated to evaluate the potential clinical application of this kind of engineered construct. rMSCs were seeded (2 × 106 cells cm,2) on the scaffold, cultured up to 21 days and analysed using appropriate techniques. Light (LM), scanning (SEM) and transmission (TEM) electron microscopy of untreated scaffold samples showed that scaffolds have a highly porous structure and are composed of 15-µm-thick microfibres having a rough surface. As detected by trypan blue stain, cell adhesion was high at day 1. rMSCs were viable up to 14 days as shown by CFDA assay and proliferated steadily on the scaffold as revealed by MTT assay. LM showed rMSCs in the innermost portions of the scaffold at day 3. SEM revealed a subconfluent cell monolayer covering 40 ± 10% of the scaffold surface at day 21. TEM of early culture showed rMSCs wrapping individual fibres with regularly spaced focal contacts, whereas confocal microscopy showed polarized expression of CD44 hyaluronan receptor; TEM of 14-day cultures evidenced fibronexus formation. Immunohistochemistry of 21-day cultures showed that fibronectin was the main matrix protein secreted in the extracellular space; decorin and versican were seen in the cell cytoplasm only and type IV collagen was minimally expressed. The expression of CD90, a marker of mesenchymal stemness, was found unaffected at the end of cell culture. Our results show that HYAFF®11 scaffolds support the adhesion, migration and proliferation of rMSCs, as well as the synthesis and delivery of extracellular matrix components under static culture conditions without any chemical induction. The high retention rate and viability of the seeded cells as well as their fine modality of interaction with the substrate suggest that such scaffolds could be potentially useful when wide tissue defects are to be repaired as in the case of cartilage repair, wound healing and large vessel replacement. [source] Developmental pathways in food allergy: a new theoretical frameworkALLERGY, Issue 4 2009A. DunnGalvin Background:, To date, there is no model of psychosocial development based on empirical food allergy (FA) research. This limits the ability of clinicians, researchers and policy-makers to predict and evaluate the real impact of FA on the child, with implications for prevention, treatment, intervention and health policy. Objectives:, To provide an integrated conceptual framework to explain the onset, development and maintenance of FA-related cognitions, emotions and behaviour, with particular attention to transition points. Method:, Fifteen focus groups meetings were held with 62 children (6,15 years). Developmentally appropriate techniques were designed to stimulate discussion, maintain interest and minimize threat to children's self-esteem. Data were analysed using grounded theory. Results:, FA impacts directly on children's normal trajectory of psychological development in both an age- and disease-specific manner. Six key themes emerged from the analysis: ,meanings of food'; ,autonomy, control and self-efficacy'; ,peer relationships'; ,risk and safety'; ,self/identity'; and ,coping strategies'. Conclusions:, Coping with FA is more than simply a strategy, it is a cumulative history of interactive processes (age, gender and disease specific) that are embedded in a child's developmental organization. Clinical Implications:, The early recognition and incorporation of an FA-specific developmental framework into a treatment plan is essential and sets the stage for an effective medical care and the eventual transition from paediatric to adult care. Capsule Summary:, This study represents a first attempt to provide an integrated developmental framework to explain the onset, development and maintenance of FA-related cognitions, emotions and behaviour. [source] The influences of macrosegregation, intermetallic particles, and dendritic spacing on the electrochemical behavior of hypoeutectic Al-Cu alloysMICROSCOPY RESEARCH AND TECHNIQUE, Issue 11 2007Wislei R. Osório Abstract The purpose of this research is (1) to investigate the influence of Al2Cu intermetallic particles associated with the dendritic arm spacing on the corrosion resistance of different hypoeutectic Al-Cu alloys and (2) to evaluate the electrochemical behavior of a hypoeutectic Al-Cu alloy directionally solidified under unsteady-state heat flow. The as-cast samples were produced using vacuum arc remelting and vertical upward water-cooled solidification. Microscopic examinations were carried out with optical microscopy and scanning electron microscopy + energy dispersiveX-ray analyses. To evaluate the surface corrosion behavior of such alloys, all corrosion tests were performed in a 0.5-M NaCl solution at 25°C using an electrochemical impedance spectroscopy technique and potentiodynamic polarization curve analysis. Based on the tests, corrosion rate and impedance parameters were obtained. The present research has underlined the use of appropriate techniques of characterization for determining Al2Cu distribution, morphology, and fraction within the typical microstructures of Al-Cu alloys. The experimental results have established correlations between the Al-rich phase dendritic arm size, the intermetallic particles distribution in the eutectic mixture, the macrosegregation profile, and the resulting corrosion resistance. Microsc. Res. Tech., 2007. © 2007 Wiley-Liss, Inc. [source] Identification of immunodominant CD4+ T cell epitopes in patients with Yersinia -induced reactive arthritis by cytometric cytokine secretion assayARTHRITIS & RHEUMATISM, Issue 11 2006Andreas Thiel Objective In reactive arthritis (ReA), a bacteria-specific T cell response to the triggering microbe is detected in synovial fluid. So far, direct characterization of bacteria-specific T cells and identification of the immunodominant fine specificities remain difficult due to the lack of appropriate techniques. The aim of the present study was to directly determine the fine specificity of CD4+ T cells specific to ReA-associated bacteria-derived protein. Methods In 2 patients with Yersinia -induced ReA, live Yersinia Hsp60,specific CD4+ T cells were directly isolated from synovial fluid after stimulation with Yersinia -derived protein Hsp60 using a cytometric cytokine secretion assay. Generated short-term T cell lines were then tested in vitro for their peptide epitope specificity. Also, direct cross-reactivity of one line with Chlamydia - and human-derived Hsp60 was assessed. Results Generated short-term CD4+ T cell lines were highly antigen-specific and revealed single immunodominant peptide epitopes that were confirmed by direct testing with single peptides in both peripheral blood and synovial fluid cells. Yersinia Hsp60,specific T cells of one patient cross-reacted directly with human Hsp60. Conclusion Our results demonstrate the feasibility of direct assessment of live, potentially pathogenic, antigen-specific interferon-,+ CD4+ T cells taken from inflammatory lesions of patients with rheumatic diseases such as ReA. This might have implications not only regarding pathogenesis, but also in the design of new immunotherapies. [source] Atrial septal interventions in patients with hypoplastic left heart syndrome,CATHETERIZATION AND CARDIOVASCULAR INTERVENTIONS, Issue 5 2008Ralf J. Holzer MD Abstract Objectives: To report an institutional experience performing percutaneous atrial septal interventions in patients with hypoplastic left heart syndrome (HLHS). Background: The success of the Hybrid approach in palliating patients with HLHS is crucially dependant on relieving any significant interatrial restriction. Data on transcatheter interventions to relieve atrial septal restrictions in patients with HLHS are limited. Methods: We retrospectively reviewed 67 transcatheter atrial septal interventions that were performed between July 2002 and September 2007 in 56 patients with HLHS. The median weight was 3.35 kg. About 10.7% of patients had an intact atrial septum. Balloon atrial septostomy (BAS) was used in 77.6% of procedures, additional techniques in 35.8% of procedures. Patients were divided into those with standard atrial septal anatomy (group A, n = 33) and those with complex atrial septal anatomy (group B, n = 23). Results: The mean trans-septal gradient was reduced significantly from 7 mm Hg to 1 mm Hg with the median time to discharge being 3.5 days. Major adverse events were seen in 8.9% of procedures, whereas minor adverse events occurred in 26.8% of procedures. Adverse events were significantly less common in patients with standard atrial septal anatomy, compared to those with complex atrial septal anatomy (25.6% versus 50.0%). About 19.6% patients required repeated atrial septal interventions. Survival up to and including Comprehensive stage II palliation was 73% group A, and 57% in group B. Conclusions: With utilization of appropriate techniques and equipment, atrial septal interventions in HLHS can be performed successfully in virtually all patients. Complex atrial septal anatomy is technically challenging and has a higher incidence of procedural adverse events. In the majority of patients, standard BAS can be performed safely, and is usually the only intervention required to achieve adequate relief of atrial septal restriction until Comprehensive stage II palliation. © 2008 Wiley-Liss, Inc. [source] | |||||||||||||