542 research outputs found
Future Perspectives in Acute Myocarditis Complicated by Cardiogenic Shock
Acute myocarditis is an inflammatory disease of the myocardium with a highly variable clinical course. Fulminant myocarditis (FM) represents the most threatening scenario with hemodynamic compromise and cardiogenic shock at presentation. Despite medical advances and the availability of promising mechanical circulatory support (MCS), FM is burdened by a dismal prognosis. Early referral to tertiary hospitals with MCS facilities and prompt diagnosis with endomyocardial biopsy are critical steps toward optimal management. Moreover, beyond supportive care, the prevention of irreversible myocardial damage with immunomodulating therapies must be proven in clinical trials. In this editorial, we briefly describe current evidence and future perspectives regarding the management of myocarditis complicated by cardiogenic shock
The role of decompressive craniectomy in the context of severe traumatic brain injury: summary of results and analysis of the confidence level of conclusions from systematic reviews and meta-analyses.
Introduction: Traumatic brain injury (TBI) is a global epidemic. The incidence of TBI in low and middle-income countries (LMICs) is three times greater than in high-income countries (HICs). Decompressive craniectomy (DC) is a surgical procedure to reduce intracranial pressure (ICP) and prevent secondary injury. Multiple comparative studies, and several randomized controlled trials (RCTs) have been conducted to investigate the influence of DC for patients with severe TBI on outcomes such as mortality, ICP, neurological outcomes, and intensive care unit (ICU) and hospital length of stay. The results of these studies are inconsistent. Systematic reviews and meta-analyses have been conducted in an effort to aggregate the data from the individual studies, and perhaps derive reliable conclusions. The purpose of this project was to conduct a review of the reviews about the effectiveness of DC to improve outcomes. Methods: We conducted a systematic search of the literature to identify reviews and meta-analyses that met our pre-determined criteria. We used the AMSTAR 2 instrument to assess the quality of each of the included reviews, and determine the level of confidence. Results: Of 973 citations from the original search, five publications were included in our review. Four of them included meta-analyses. For mortality, three reviews found a positive effect of DC compared to medical management and two found no significant difference between groups. The four reviews that measured neurological outcome found no benefit of DC. The two reviews that assessed ICP both found DC to be beneficial in reducing ICP. DC demonstrated a significant reduction in ICU length of stay in the one study that measured it, and a significant reduction in hospital length of stay in the two studies that measured it. According to the AMSTAR 2 criteria, the five reviews ranged in levels of confidence from low to critically low. Conclusion: Systematic reviews and meta-analyses are important approaches for aggregating information from multiple studies. Clinicians rely of these methods for concise interpretation of scientific literature. Standards for quality of systematic reviews and meta-analyses have been established to support the quality of the reviews being produced. In the case of DC, more attention must be paid to quality standards, in the generation of both individual studies and reviews
An anatomico-surgical study of the temporal branch of the facial nerve.
The surgical anatomy of the temporal branch of the facial nerve was studied bilaterally in 10 embalmed cadaveric heads. Particular attention was paid to the relationships between the temporal branch, the galeal-fascial layers, and the fat pads of the temporal-zygomatic region. The temporal branch of the facial nerve pierces the parotidomasseteric fascia below the zygomatic arch. This branch travels first in the subcutaneous tissue and then, above the zygomatic arch, in the subgaleal space. The temporal branch divides into an anterior, a middle (frontal), and a posterior ramus soon after it pierces the parotid fascia. The course of the terminal twigs of the temporal branch of the facial nerve in the subgaleal space is extremely variable, with their location being at times posterior to the anterior one-fourth of the temporalis muscle. Occasionally, a twig for the frontalis muscle may run in between the two layers of the superficial temporal fascia. Because of these findings (anteroposterior variability of temporal branch twigs and recurrent intrafascial twig), Yasargil's interfascial dissection may at times fail. A combined frontotemporal scalp/superficial temporal fascia dissection is anatomically suited to preserve the temporal branch of the facial nerve
Prediction of flow induced vibration of a flat plate located after a bluff wall mounted obstacle
[EN] Accurate prediction of Flow Induced Vibration phenomena is currently a field of major interest due to the use of lightweight materials in the automotive and aerospace industry. This article studies the turbulent flow around a wall-mounted obstacle, and the induced deformations produced by the pressure fluctuations on a plate located downstream the obstacle. The methodology used is a combination of experimental tests and numerical simulations. On one side, experiments were carried out in a wind tunnel test facility equipped with Particle Image Velocimetry to characterize the fluid velocity field, and laser vibro-meter to measure the vibrations of the plate. On the other side, Fluid-Structure Interaction (FSI-one-way) has been calculated by considering different turbulence modeling approximations (RANS and LES). Finally, numerical results have been analyzed and validated against the experiments in terms of main flow structures and the vibroacoustic response of the plate.This work has been partially supported by Universitat Politecnica de Valencia through the grant Programa de apoyo a la Carrera Academica del Profesorado 2018/03/14 and by the Spanish Ministerio de Economia y Competitividad through Grant No. DPI2015-70464-R. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center), funded by the Research Foundation Flanders and the Flemish Government department EWI. The Research Fund KU Leuven and the Flanders Innovation and Entrepreneurship Agency, within the SILENCEVENT project, are gratefully acknowledged for their support.Torregrosa, AJ.; Gil, A.; Quintero-Igeño, P.; Ammirati, A.; Denayer, H.; Desmet, W. (2019). Prediction of flow induced vibration of a flat plate located after a bluff wall mounted obstacle. Journal of Wind Engineering and Industrial Aerodynamics. 190:23-39. https://doi.org/10.1016/j.jweia.2019.04.008S233919
Taxonomy Based on Science is Necessary for Global Conservation
Taxonomy is a scientific discipline that has provided the universal naming and classification system of biodiversity for centuries and continues effectively to accommodate new knowledge. A recent publication by Garnett and Christidis (Garnett ST, Christidis L. Taxonomy anarchy hampers conservation. Nature. 2017; 546(7656):25±27. https://doi.org/10.1038/546025a) expressed concerns regarding the difficulty that taxonomic changes represent for conservation efforts and proposed the establishment of a system to govern taxonomic changes. Their proposal to restrict the freedom of taxonomic action through governing subcommittees that would review taxonomic papers for compliance and their assertion that the scientific community\u27s failure to govern taxonomy threatens the effectiveness of global efforts to halt biodiversity loss, damages the credibility of science, and is expensive to society are flawed in many respects. They also assert that the lack of governance of taxonomy damages conservation efforts, harms the credibility of science, and is costly to society. Despite its fairly recent release, Garnett and Christidis\u27 proposition has already been rejected by a number of colleagues. Herein, we contribute to the conversation between taxonomists and conservation biologists aiming to clarify some misunderstandings and issues in the proposition by Garnett and Christidis.
Placing governance over the science of taxonomy blurs the distinction between taxonomy and nomenclature. Garnett and Christidis’s proposal is far-reaching but represents a narrow perspective of taxonomy, as utilized by conservation, and reflects an increasingly broad misunderstanding throughout biology of the scientific basis of taxonomy, formalized nomenclature, and the relationship between them. This trend may have resulted from the attenuation of instruction in taxonomic principles and, in particular, nomenclature at many universities, in part because of a shift in research priorities away from taxonomy.
Garnett and Christidis assert that an “assumption that species are fixed entities underpins every international agreement on biodiversity conservation.” This assumption demonstrates a fundamental misunderstanding of taxonomy and the evolving view of what species represent. The essential features of science include documenting natural patterns and processes, developing and testing hypotheses, and refining existing ideas and descriptions of nature based on new data and insights. Taxonomy, the science of recognizing and delimiting species, adheres to these fundamental principles. Discoveries of new organisms together with advances in methodology continue unabated, leading to a constant reevaluation of the boundaries between taxonomic entities. Species (and higher taxa) comprise related organisms that may be clustered together differently depending on which sets of criteria are emphasized. Hey et al. acknowledge “the inherent ambiguity of species in nature” but point out that “species-related research and conservation efforts can proceed without suffering from, and without fear of, the ambiguity of species.” Through taxonomic research, our understanding of biodiversity and classifications of living organisms will continue to progress. Any system that restricts such progress runs counter to basic scientific principles, which rely on peer review and subsequent acceptance or rejection by the community, rather than third-party regulation. Thiele and Yeates cautioned that such a system “could lead to authoritarianism and a stifling of innovative taxonomic viewpoints. No other hypothesis-driven field of science would accept such a straitjacket”.
Taxonomy and associated nomenclature are not without problems. Even with a common set of facts, alternative interpretations of how to classify organisms can lead to differing classifications. However, the science of taxonomy is increasingly rigorous, which can improve the foundation for targeted legislative action regarding species. Taxonomic instability does not affect all taxonomic groups equally. Garnett and Christidis provide examples from mammals and birds, which collectively represent a small fraction
New Onset Cardiac Murmur and Exertional Dyspnea in an Apparently Healthy Child: A Rare Localization of Obstructive Myxoma in the Right Ventricle Outflow Tract without Pulmonary Embolization-A Case Report and Literature Review
Myxomas are slowly growing benign neoplasms which are rare in children. Up to 80% can be located in the left atrium and generate symptoms such as embolism, cardiac failure, fever and weight loss. Rarely, myxomas can be detected in the right ventricle outflow tract, causing arrhythmias, pulmonary emboli and sudden death. We report the case of a 13-year-old healthy child brought to the Emergency Department (ED) of the Children's Hospital Bambino Gesu, Rome, for recent dyspnea, chest pain on exertion and new onset cardiac murmur. Patient underwent medical examination and echocardiogram with the finding of a rounded and lobulated voluminous mass in the right ventricle outflow tract (RVOT) which caused severe obstruction. The contrast computed tomography (CT) scan confirmed the presence of a heterogeneously enhancing soft-tissue mass occupying the RVOT with no evidence of pulmonary embolization. The mass was surgically excised, and the pathologic examination confirmed our suspicion of myxoma. Our experience suggests that myxoma can have mild clinical symptoms, the presentation may be non-specific, and diagnosis can be a challenge Careful examination and a diagnostic imaging workup, primarily with the transthoracic echocardiogram, are needful to make a rapid differential diagnosis and to better manage surgical treatment and follow-up
The Role of Multiparametric Magnetic Resonance in Volumetric Modulated Arc Radiation Therapy Planning for Prostate Cancer Recurrence After Radical Prostatectomy: A Pilot Study
Background and Purpose: Volumetric modulated arc radiotherapy (RT) has become pivotal in the treatment of prostate cancer recurrence (RPC) to optimize dose distribution and minimize toxicity, thanks to the high-precision delineation of prostate bed contours and organs at risk (OARs) under multiparametric magnetic resonance (mpMRI) guidance. We aimed to assess the role of pre-treatment mpMRI in ensuring target volume coverage and normal tissue sparing.
Material and Methods: Patients with post-prostatectomy RPC eligible for salvage RT were prospectively recruited to this pilot study. Image registration between planning CT scan and T2w pre-treatment mpMRI was performed. Two sets of volumes were outlined, and DWI images/ADC maps were used to facilitate precise gross tumor volume (GTV) delineation on morphological MRI scans. Two rival plans (mpMRI-based or not) were drawn up.
Results: Ten patients with evidence of RPC after prostatectomy were eligible. Preliminary data showed lower mpMRI-based clinical target volumes than CT-based RT planning (p = 0.0003): median volume difference 17.5 cm3. There were no differences in the boost volume coverage nor the dose delivered to the femoral heads and penile bulb, but median rectal and bladder V70Gy was 4% less (p = 0.005 and p = 0.210, respectively) for mpMRI-based segmentation.
Conclusions: mpMRI provides high-precision target delineation and improves the accuracy of RT planning for post-prostatectomy RPC, ensures better volume coverage with better OARs sparing and allows non-homogeneous dose distribution, with an aggressive dose escalation to the GTV. Randomized phase III trials and wider datasets are needed to fully assess the role of mpMRI in optimizing therapeutic strategies
Management of syncope: clinical and economic impact of a Syncope Unit
Aims Aim of this observational study is to evaluate the clinical performance of a Syncope Unit, in order to assess whether the implemented organization really improves syncope management. Methods and results The study enrolled patients with unexplained syncope who were consecutively referred to our Syncope Unit, either as outpatients or during hospitalization, in a 2-month period. The design of this observational study consists in three phases: a retrospective analysis of their clinical. management in the 9 months prior to the first attendance at the Syncope Unit (phase one), their subsequent clinical management in the Syncope Unit (phase two) and a 9-month follow-up (phase three). The retrospective analysis of phase one showed that 25% of patients had already been hospitalized without diagnosis. After Syncope Unit evaluation, diagnosis was obtained in 82% of patients, with 15% of patients indicated to pacing. In the follow-up, 23% of patients experienced a syncopal recurrence. Our analysis indicated an 85% reduction of hospital costs in the follow-up period. Conclusion The clinical and economic analysis of the three phases of our study demonstrates that a Syncope Unit allows an improved management of patients with syncope
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