178 research outputs found
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The Yippies.: an inquiry into the concept of cultural revolution.
Thesis (M.A.
The Need for Advanced Cardiac Life Support Certification for Open-Water Lifeguards at Huntington Beach, CA
The number of people visiting U.S. beaches increased in 2007 to more than 240 million people. This increase in activities does not come without danger. Lifeguards maintain beach safety, but little research is available to assist us in determining appropriate certification levels for lifeguards. The authors analyzed various injuries that occurred in the open-water environment of Huntington Beach, CA. Based on the nature of the injuries, they attempted to determine the level of training lifeguards needed. The vast majority of injuries (99%) were soft-tissue injuries, musculoskeletal injuries, or environmental injuries. It was felt that lifeguards with first-aid and basic-life-support (BLS) -level training were able to handle these injuries adequately and that advanced cardiac life support (ACLS) was not necessary. Injuries that happened at Huntington Beach primarily required lifeguards with first-aid and BLS training. It does not seem necessary that all open-water lifeguards be trained in ACLS
Clinical application of cardiac scintigraphy with bone tracers: controversies and pitfalls in cardiac amyloidosis
Cardiac amyloidosis (CA) is a life-threatening disease caused by extracellular deposition of amyloidogenic proteins in the heart tissue; it could be associated with a poor prognosis and remains underdiagnosed and underestimated. During the last years, bone scintigraphy has been widely used to facilitate the diagnosis of CA, avoid endomyocardial biopsy, and differentiate amyloid light-chain amyloidosis from transthyretin amyloidosis. Technetium-99m pyrophosphate (99mTc-PYP) is the most used tracer in the United States, but a standardized and shared acquisition protocol is still lacking; technetium-99m 3,3-diphosphono-1,2-propanodicarboxylic acid (99mTc-DPD) is widely used in Europe and can count on a more grounded data than 99mTc-PYP. Both tracers suffer from some diagnostic limitations (due to their biochemical characteristics) and pitfalls that can lead to a misdiagnosis of CA. We aim to briefly describe the main differences between 99mTc-PYP and 99mTc-DPD, analyzing the data available in the literature and highlighting the most frequent causes of misdiagnosis and pitfalls. Both 99mTc-DPD and 99mTc-PYP show good accuracy for the diagnosis of CA with high specificity and sensibility. Nevertheless, to achieve this accuracy, the correct acquisition protocols must be followed for each tracer, as suggested in the latest recommendation. Proper diagnosis of CA has a crucial role in patient management; therefore, it is important for nuclear physicians to have the most specific approaches in acquiring and interpreting bone scintigraphy for transthyretin cardiac amyloidosis
Validation and Performance Comparison of Two Scoring Systems Created Specifically to Predict the Risk of Deep Sternal Wound Infection after Bilateral Internal Thoracic Artery Grafting
Background: The Gatti and the bilateral internal mammary artery (BIMA) scores were created to predict the risk of deep sternal wound infection (DSWI) after bilateral internal thoracic artery (BITA) grafting. Methods: Both scores were evaluated retrospectively in two consecutive series of patients undergoing isolated multi-vessel coronary surgical procedures - i.e., the Trieste (n = 1,122; BITA use, 52.1%; rate of DSWI, 5.7%) and the Besan\ue7on cohort (n = 721; BITA use, 100%; rate of DSWI, 2.5%). Baseline patient characteristics were compared between the two validation samples. For each score, the accuracy of prediction and predictive power were assessed by the area under the receiver-operating characteristic curve (AUC) and the Goodman-Kruskal gamma coefficient, respectively. Results: There were significant differences between the two series in terms of age, gender, New York Heart Association functional class, chronic lung disease, left ventricular function, surgical priority, and the surgical techniques used. In the Trieste series, accuracy of prediction of the Gatti score for DSWI was higher than that of the BIMA score (AUC, 0.729 vs. 0.620, p = 0.0033). The difference was not significant, however, in the Besan\ue7on series (AUC, 0.845 vs. 0.853, p = 0.880) and when only BITA patients of the Trieste series were considered for analysis (AUC, 0.738 vs. 0.665, p = 0.157). In both series, predictive power was at least moderate for the Gatti score and low for the BIMA score. Conclusions: The Gatti and the BIMA scores seem to be useful for pre-operative evaluation of the risk of DSWI after BITA grafting. Further validation studies should be performed
C. elegans expressing human β2-microglobulin: a novel model for studying the relationship between the molecular assembly and the toxic phenotype.
Availability of living organisms to mimic key step of amyloidogenesis of human protein has become an indispensable tool for our translation approach aiming at filling the deep gap existing between the biophysical and biochemical data obtained in vitro and the pathological features observed in patients. Human β(2)-microglobulin (β(2)-m) causes systemic amyloidosis in haemodialysed patients. The structure, misfolding propensity, kinetics of fibrillogenesis and cytotoxicity of this protein, in vitro, have been studied more extensively than for any other globular protein. However, no suitable animal model for β(2)-m amyloidosis has been so far reported. We have now established and characterized three new transgenic C. elegans strains expressing wild type human β(2)-m and two highly amyloidogenic isoforms: P32G variant and the truncated form ΔN6 lacking of the 6 N-terminal residues. The expression of human β(2)-m affects the larval growth of C. elegans and the severity of the damage correlates with the intrinsic propensity to self-aggregate that has been reported in previous in vitro studies. We have no evidence of the formation of amyloid deposits in the body-wall muscles of worms. However, we discovered a strict correlation between the pathological phenotype and the presence of oligomeric species recognized by the A11 antibody. The strains expressing human β(2)-m exhibit a locomotory defect quantified with the body bends assay. Here we show that tetracyclines can correct this abnormality confirming that these compounds are able to protect a living organism from the proteotoxicity of human β(2)-m
Grey zones in the supportive treatments of cardiac amyloidosis
Recent advances in the diagnosis and treatment of cardiac amyloidosis (CA) have translated into a longer life expectancy of patients and more challenging clinical scenarios. Compared to the past, patients with CA and heart failure (HF) currently encountered in clinical practice are a more heterogeneous population and require tailored strategies. The perception of CA as a treatable disease has opened new possibilities for the management of these patients, but many grey areas remain to be explored. The aim of this review is to provide practical suggestions for daily clinical activity in the management of challenging scenarios in CA, including the effectiveness and tolerability of evidence-based HF medication; rate vs. rhythm control in atrial fibrillation, thromboembolic risk, and anticoagulation therapies; replacement of severe aortic valve stenosis; the impact of implantable cardioverter defibrillator on survival; and the usefulness of cardiac resynchronization therapy
From direct to inverse Giant Magnetocaloric Effect in Co-doped NiMnGa multifunctional alloys
We report the magnetic and magnetocaloric properties in Co-doped Ni–Mn–Ga Heusler alloys around the Mn-rich composition
Ni50Mn30Ga20. The presence of Co affects profoundly the critical temperatures and alters the exchange interactions of martensite and
austenite to different extents; by varying the composition it is possible to tune the critical temperatures and to induce a paramagnetic
gap between the magnetically ordered martensite and magnetic austenite, thus giving rise to a reverse magnetostructural transformation.
Contrary to the Co-free alloys, the saturation magnetization moment of austenite is strongly enhanced by Co with respect to the martensitic one: thus the magnetocaloric effect turns from direct into inverse. Remarkable values of the magnetic properties related to the magnetocaloric effect, e.g. the saturation magnetization jump at the transformation (DM) and the field dependence of the transformation temperature (dT/dH) are reported, together with high positive values of the isothermal magnetic entropy change (DS). The conditions for
enhancing the magnetocaloric properties and triggering the sign reversal of the magnetocaloric effect are discussed
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