56 research outputs found

    Should electric fans be used during a heat wave?

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    Heat waves continue to claim lives, with the elderly and poor at greatest risk. A simple and cost-effective intervention is an electric fan, but public health agencies warn against their use despite no evidence refuting their efficacy in heat waves. A conceptual human heat balance model can be used to estimate the evaporative requirement for heat balance, the potential for evaporative heat loss from the skin, and the predicted sweat rate, with and without an electrical fan during heat wave conditions. Using criteria defined by the literature, it is clear that fans increase the predicted critical environmental limits for both the physiological compensation of endogenous/exogenous heat, and the onset of cardiovascular strain by an air temperature of ~3-4°C, irrespective of relative humidity (RH) for the young and elderly. Even above these critical limits, fans would apparently still provide marginal benefits at air temperatures as high as 51.1°C at 10%RH for young adults and 48.1°C at 10%RH for the elderly. Previous concerns that dehydration would be exacerbated with fan use do not seem likely, except under very hot (>40°C) and dry (<10%RH) conditions, when predicted sweat losses are only greater with fans by a minor amount (~20-30 mL/hour). Relative to the peak outdoor environmental conditions reported during ten of the most severe heat waves in recent history, fan use would be advisable in all of these situations, even when reducing the predicted maximum sweat output for the elderly. The protective benefit of fans appears to be underestimated by current guidelines

    Rapid automatic segmentation of abnormal tissue in late gadolinium enhancement cardiovascular magnetic resonance images for improved management of long-standing persistent atrial fibrillation

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    Background: Atrial fibrillation (AF) is the most common heart rhythm disorder. In order for late Gd enhancement cardiovascular magnetic resonance (LGE CMR) to ameliorate the AF management, the ready availability of the accurate enhancement segmentation is required. However, the computer-aided segmentation of enhancement in LGE CMR of AF is still an open question. Additionally, the number of centres that have reported successful application of LGE CMR to guide clinical AF strategies remains low, while the debate on LGE CMR’s diagnostic ability for AF still holds. The aim of this study is to propose a method that reliably distinguishes enhanced (abnormal) from non-enhanced (healthy) tissue within the left atrial wall of (pre-ablation and 3 months post-ablation) LGE CMR data-sets from long-standing persistent AF patients studied at our centre. Methods: Enhancement segmentation was achieved by employing thresholds benchmarked against the statistics of the whole left atrial blood-pool (LABP). The test-set cross-validation mechanism was applied to determine the input feature representation and algorithm that best predict enhancement threshold levels. Results: Global normalized intensity threshold levels T PRE = 1 1/4 and T POST = 1 5/8 were found to segment enhancement in data-sets acquired pre-ablation and at 3 months post-ablation, respectively. The segmentation results were corroborated by using visual inspection of LGE CMR brightness levels and one endocardial bipolar voltage map. The measured extent of pre-ablation fibrosis fell within the normal range for the specific arrhythmia phenotype. 3D volume renderings of segmented post-ablation enhancement emulated the expected ablation lesion patterns. By comparing our technique with other related approaches that proposed different threshold levels (although they also relied on reference regions from within the LABP) for segmenting enhancement in LGE CMR data-sets of AF patients, we illustrated that the cut-off levels employed by other centres may not be usable for clinical studies performed in our centre. Conclusions: The proposed technique has great potential for successful employment in the AF management within our centre. It provides a highly desirable validation of the LGE CMR technique for AF studies. Inter-centre differences in the CMR acquisition protocol and image analysis strategy inevitably impede the selection of a universally optimal algorithm for segmentation of enhancement in AF studies

    How reliable is assessment of true vocal cord-arytenoid unit mobility in patients affected by laryngeal cancer? a multi-institutional study on 366 patients from the ARYFIX collaborative group

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    Purpose: In clinical practice the assessment of the "vocal cord-arytenoid unit" (VCAU) mobility is crucial in the staging, prognosis, and choice of treatment of laryngeal squamous cell carcinoma (LSCC). The aim of the present study was to measure repeatability and reliability of clinical assessment of VCAU mobility and radiologic analysis of posterior laryngeal extension. Methods: In this multi-institutional retrospective study, patients with LSCC-induced impairment of VCAU mobility who received curative treatment were included; pre-treatment endoscopy and contrast-enhanced imaging were collected and evaluated by raters. According to their evaluations, concordance, number of assigned categories, and inter- and intra-rater agreement were calculated. Results: Twenty-two otorhinolaryngologists evaluated 366 videolaryngoscopies (total evaluations: 2170) and 6 radiologists evaluated 237 imaging studies (total evaluations: 477). The concordance of clinical rating was excellent in only 22.7% of cases. Overall, inter- and intra-rater agreement was weak. Supraglottic cancers and transoral endoscopy were associated with the lowest inter-observer reliability values. Radiologic inter-rater agreement was low and did not vary with imaging technique. Intra-rater reliability of radiologic evaluation was optimal. Conclusions: The current methods to assess VCAU mobility and posterior extension of LSCC are flawed by weak inter-observer agreement and reliability. Radiologic evaluation was characterized by very high intra-rater agreement, but weak inter-observer reliability. The relevance of VCAU mobility assessment in laryngeal oncology should be re-weighted. Patients affected by LSCC requiring imaging should be referred to dedicated radiologists with experience in head and neck oncology

    Heat risk exacerbation potential for neurology patients during the COVID-19 pandemic and related isolation

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    COVID-19 may increase the risk of heat-related symptoms during hot weather since vulnerable populations, including the elderly and those with neurological disabilities, must continue to self-isolate, often indoors. Within the chronic neurological patient population, indoor conditions in summer months present a hazard because of impaired and/or altered thermoregulation, including poor hydration status due to both autonomic and behavioral dysfunction(s). To address this increased risk, telemedicine protocols should include an assessment of the patient\u2019s environmental parameters, and when combined with physiological data from wearable devices, identify those with neurological diseases who are at higher risk of heat illness. Personalized medicine during times of self-isolation must be encouraged, and using smart technology in ambient assisted living solutions, including e-health to monitor physiological parameters are highly recommended, not only during extreme weather conditions but also during times of increased isolation and vulnerability

    Alkaloids from croton echinocarpus baill.: Anti-hiv potential

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    Croton belongs to the Euphorbiaceae genus, one of the major Angiosperms families, and is widely distributed throughout the world, especially in the tropics. In this study, the hydroalcoholic extract (70% EtOH) of Croton echinocarpus leaves afforded two alkaloids: corydine and norisoboldine, and their structures were established by spectroscopic data interpretation (UV, IR, NMR and LREIMS). Both alkaloids displayed significant in vitro anti-HIV potential, inhibiting 40% of the HIV-1 reverse transcriptase enzyme activity at a concentration of 100 mu g mL(-1) of norisoboldine and 450 mu g mL(-1) of corydine. Corydine showed IC50 of 356.8 mu g mL(-1), while norisoboldine was more efficient on inhibiting the RT activity, showing IC50 of 153.7 mu g mL(-1). (C) 2015 SAAB. Published by Elsevier B.V. All rights reserved.Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP) [FAPESP 2012/10079-0]Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES)Department of Botany, Institute of Bioscience, University of SĂŁo Paulo, Rua do MatĂŁo 277, CEP 05508-090 SĂŁo Paulo, SP, BrazilUniversidade Paulista, Rua Apeninos 267, CEP 01533-000 SĂŁo Paulo, SP, BrazilInstituto de CiĂȘncias Ambientais, QuĂ­micas e FarmacĂȘuticas, Universidade Federal de SĂŁo Paulo, Rua Prof. Arthur Riedel 275, CEP 09972-270 Diadema, SP, BrazilInstituto de CiĂȘncias Ambientais, QuĂ­micas e FarmacĂȘuticas, Universidade Federal de SĂŁo Paulo, Rua Prof. Arthur Riedel 275, CEP 09972-270 Diadema, SP, BrazilFAPESP: 2012/10079-0Web of Scienc

    Sharing soil and building geophysical data for seismic characterization of cities using CLARA Webgis. A case study of Matera (southern Italy)

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    In the context of seismic risk, studying the characteristics of urban soils and of the built environment means adopting a holistic vision of the city, taking a step forward compared to the current microzonation approach. Based on this principle, CLARA WebGIS aims to collect, organize, and disseminate the available information on soils and buildings in the urban area of Matera. The geodatabase is populated with (i) 488 downloadable geological, geotechnical, and geophysical surveys; (ii) geological, geomorphological, and seismic homogeneous microzone maps; and (iii) a new Digital Surface Model. The CLARA WebGIS is the first publicly available database that reports for the whole urban area the spatial distribution of the fundamental frequencies for soils and the overlying 4043 buildings, along with probability levels of soil‐building resonance. The WebGIS is aimed at a broad range of end users (local government, engineers, geologists, etc.) as a support to the implementation of seismic risk mitigation strategies in terms of urban planning, seismic retrofitting, and management of post‐earthquake crises. We recommend that the database be managed by local administrators, who would also have the task of deciding on future developments and continuous updating as new data becomes available

    The role of emergency presentation and revascularization in aneurysms of the peripancreatic arteries secondary to celiac trunk or superior mesenteric artery occlusion

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    Objective: The goal of this study was to analyze our 10-year experience in the treatment of aneurysms of the collateral circulation secondary to steno-occlusions of the celiac trunk (CT) or superior mesenteric artery (SMA). Methods: In the last 10 years, 32 celiac-mesenteric aneurysms were detected (25 true aneurysms and seven pseudoaneurysms) in 25 patients with steno-occlusion of the CT or SMA. All cases were diagnosed and treated at our center, with either surgical or endovascular approach. As open surgery, we performed aneurysmectomy and revascularization; as endovascular treatment we performed both the embolization (or graft exclusion) of the aneurysm sac, and embolization of afferent and efferent arteries. Results: Sixteen patients (64%) underwent endovascular treatment, accounting for 66% of aneurysms (21/32). Six patients (24%) and seven associated aneurysms (22%) underwent open surgery. Three asymptomatic patients (12%), representing a total of four aneurysms (12%), were not treated. For endovascular procedures, the technical success rate was 90%, with a 56% clinical success rate. For open surgery, clinical and technical success were achieved in five patients (83%) and six procedures (86%), respectively. Sixty-eight percent of patients (17/25) were treated in an emergency setting, using either endovascular (88%) or open (12%) approaches. Although technical success was achieved in more than 85% of these procedures for both approaches, clinical success was reached less frequently among patients with an acute presentation (P =.041). Regardless of the type of treatment, CT or SMA revascularization during the first procedure did not show an increased rate of clinical success (P =.531). However, we reported four cases of visceral ischemia after an endovascular approach without revascularization, with three open surgical corrections required. The mean follow-up was 41 months (range, 0-136 months). Conclusions: Neither of the approaches described qualifies as a standard optimal choice. We suggest a tailored therapeutic approach based on the clinical condition at the time of diagnosis and specific vascular anatomy
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