Ethanol and erythrocyte membrane interaction : a hemorheologic perspective

© 1999 – IOS Press. All rights reservedPrevious studies have documented structural and functional changes induced by ethanol–erythrocyte membrane interaction. In order to perform an in vitro study on the effect of different ethanol concentrations on erythrocyte hemorheologic properties, blood samples were collected from 21 male donors at the Hospital of Santa Maria. Whole blood aliquots were incubated with ethanol solutions of rising concentrations. The following parameters were measured: erythrocyte aggregation, haemoglobin, carboxyhaemoglobin and methaemoglobin concentrations, hematocrit, plasma osmolality and erythrocyte membrane fluidity (fluorescence polarisation probes TMA-DPH and DPH). With ethanol blood concentrations of 45 mM a rise in plasma osmolality (0.352 Osm/kg H2O vs 0.310 Osm/kg H2O; p < 0.001) was verified. With 67 mM concentration a decrease of erythrocyte aggregation (11.03 vs 12.81; p < 0.05) and an increase in plasma osmolality (0.380 Osm/kg H2O vs 0.310 Osm/kg H2O;p < 0.001) were obtained. In conclusion, ethanol only changes erythrocyte aggregation for a concentration of 67 mM. These data could lead to future changes in therapeutic approaches to situations such as alcoholic coma

Bilateral versus ipsilesional cortico-subcortical activity patterns in stroke show hemispheric dependence

Background Understanding of interhemispheric interactions in stroke patients during motor control is an important clinical neuroscience quest that may provide important clues for neurorehabilitation. In stroke patients, bilateral overactivation in both hemispheres has been interpreted as a poor prognostic indicator of functional recovery. In contrast, ipsilesional patterns have been linked with better motor outcomes. Aim We investigated the pathophysiology of hemispheric interactions during limb movement without and with contralateral restraint, to mimic the effects of constraint-induced movement therapy. We used neuroimaging to probe brain activity with such a movement-dependent interhemispheric modulation paradigm. Methods We used an fMRI block design during which the plegic/paretic upper limb was recruited/mobilized to perform unilateral arm elevation, as a function of presence versus absence of contralateral limb restriction ( n = 20, with balanced left/right lesion sites). Results Analysis of 10 right-hemispheric stroke participants yielded bilateral sensorimotor cortex activation in all movement phases in contrast with the unilateral dominance seen in the 10 left-hemispheric stroke participants. Superimposition of contralateral restriction led to a prominent shift from activation to deactivation response patterns, in particular in cortical and basal ganglia motor areas in right-hemispheric stroke. Left-hemispheric stroke was in general characterized by reduced activation patterns, even in the absence of restriction, which induced additional cortical silencing. Conclusion The observed hemispheric-dependent activation/deactivation shifts are novel and these pathophysiological observations suggest short-term neuroplasticity that may be useful for hemisphere-tailored neurorehabilitation.info:eu-repo/semantics/publishedVersio

Monitorização dos insetos potenciais vectores de Xylella fastidiosa na Herdade da Abóbada

Xylella fastidiosa é uma bactéria de quarentena restrita ao fluido xilémico de uma vasta gama de hospedeiros vegetais, alguns dos quais constituindo culturas agrícolas e florestais de grande importância económica para Portugal. A bactéria é transportada e transmitida por insetos picadores-sugadores de fluido xilémico, nomeadamente Hemiptera Auchenorrhyncha (Cicadomorpha). Em Itália, Philaenus spumarius (Hemiptera: Aphrophoridae); está identificado como vetor, mas muitas outras espécies, também existentes em Portugal, são consideradas potenciais vetores deste patogéneo. Portugal corre um sério risco de ver esta bactéria disseminada no país, pela sua localização geográfica e relações comerciais; invernos amenos; ampla presença de hospedeiros preferenciais da bactéria (oliveira, vinha, citrinos, amendoeira, ameixeira, loendros e Quercus); e presença de P. spumarius e de outras espécies de insetos conotadas como “potenciais vetores”. O Instituto Nacional de Investigação Agrária e Veterinária (INIAV) lidera um projeto de investigação FCT (PTDC/AGR-PRO/0856/2014), que, entre outros objectivos pretende inventariar os insetos com potencial para disseminar a X. fastidiosa nos olivais portugueses. Com este trabalho pretende-se realizar a inventariação dos insectos potenciais vectores da bactéria numa parcela de olival da Herdade da Abóbada (Serpa). Para o efeito efectuaram-se entre abril e novembro do ano de 2018, as amostragens recorrendo à técnica do varrimento nas plantas espontâneas da entrelinha com uma periodicidade semanal, e colocação/substituição de armadilhas adesivas amarelas com uma periodicidade quinzenal. Os resultados das amostragens realizadas permitem-nos verificar uma maior abundância de insectos com potencial para vetor de X. fastidiosa, em meados do mês de julho e início de agosto. No final de abril e meados de maio, detetámos a presença de indivíduos Philaenus sp. nalgumas espécies de plantas espontâneas, nomeadamente: Geranium dissectum (coentrinho), Mentha suavelens (hortelã), Bromus diandrus (espigão), Avena sterilis (balanco), Sonchus oleraceae (serralha), Echinochloa colona, Lactuca serriola (alface brava) e Erodium malacoides (mariafia)

[Carotid atherosclerosis and white matter hypodensities: a controversial relationship]

INTRODUCTION: White matter hypodensities of presumed vascular origin, are recognized as an important cause of morbidity with established clinical and cognitive consequences. Nonetheless, many doubts remain on its physiopathology. Our goal is to clarify the potential role of carotid atherosclerosis and other vascular risk factors in the development of white matter hypodensities of presumed vascular origin. MATERIAL AND METHODS: We included patients that underwent CT brain scan and neurosonologic evaluation within a one-month period. Full assessment of vascular risks factors was performed. We seek to find independent associations between white matter hypodensities of presumed vascular origin, carotid intima-media thickness and vascular risk factors. RESULTS: 472 patients were included, mean age was 67.32 (SD: 14.75), 274 (58.1%) were male. The independent predictors of white matter hypodensities of presumed vascular origin were age (OR: 1.067, 95% IC: 1.049 - 1.086, p < 0.001) and hypertension (OR: 1.726, 95% IC: 1.097 - 2.715, p = 0.018). No association was found between IMT (OR: 2.613, 95% IC: 0.886 - 7.708, p = 0.082) or carotid artery stenosis (OR: 1.021, 95% IC: 0.785 - 1.328, p = 0.877) and white matter hypodensities of presumed vascular origin. DISCUSSION: Only age and hypertension proved to have an independent association with white matter hypodensities of presumed vascular origin. Carotid atherosclerosis, evaluated by IMT and the degree of carotid artery stenosis, showed no association with white matter hypodensities of presumed vascular origin. Since atherosclerosis is a systemic pathology, these results suggest that alternative mechanisms are responsible for the development of white matter hypodensities of presumed vascular origin. CONCLUSION: Age and hypertension seem to be the main factors in the development of white matter hypodensities of presumed vascular origin. No association was found between carotid atherosclerosis and white matter hypodensities of presumed vascular origin

Nocturnal Blood Pressure Dipping in Acute Ischemic Stroke

OBJECTIVES: We aim to assess the impact of early nocturnal blood pressure (BP) variation in the functional outcome of patients after an acute ischemic stroke. MATERIALS AND METHODS: We included consecutive stroke patients treated with intravenous thrombolysis (IVrtPA) in a tertiary stroke center. BP measurements were performed at regular intervals throughout day and night during the first 48 h after stroke onset, and subjects were divided into four dipping categories (extreme dippers, dippers, non-dippers, and reverse dippers). Recanalization was assessed by transcranial color-coded Doppler and/or angiographic CT. Hemorrhagic transformation was evaluated at 24 h follow-up CT scan. Functional outcome was evaluated at 3 months after stroke using the modified Rankin Scale. RESULTS: A total of 304 patients were included, mean age 72.80 ± 11.10 years. After 24 h of systolic BP monitoring, 30.59% were classified as reverse dippers, 39.14% as non-dippers, 19.10% as dippers, and 11.18% as extreme dippers. Multivariate analysis did not show an independent association of any dipping class with 3-month functional outcome. Hemorrhagic transformation was not uniform between dipping classes: 25.81% for reverse dippers, 14.29% for non-dippers, 15.52% for dippers, and 5.88% for extreme dippers, P = 0.033. CONCLUSIONS: Nocturnal BP dipping pattern is not associated with functional outcome at 3 months in acute stroke patients treated with IVrtPA. Hemorrhagic transformation was more frequent in reverse dippers.info:eu-repo/semantics/publishedVersio

A Potential Link Between Prolonged Cork Exposure and Intestinal-Type Sinonasal Adenocarcinoma – Special Findings of a Retrospective Cohort Analysis

Introduction: intestinal-type sinonasal adenocarcinoma (ITAC) is a rare epithelium tumor of the nasal cavities and paranasal sinuses. Exposure to wood and leather dusts is a strong etiological factor related to its development. Prolonged cork exposure has rarely been associated. Materials and methods: thirty-seven-year (1981-2018) retrospective cohort analysis of all consecutive patients with sinonasal cancer (SNC) followed at our institution. Medical records were reviewed to determine patient demographics, occupational/environmental exposure, location and extent of the tumor, stage, histopathology findings, treatment strategies, and oncologic outcomes. Survival analysis was done using Kaplan-Meier method. Results: we evaluated 379 patients with SNC, including 39 (10.3%) ITAC. Patient median age was 73 years (range 49-87), 56% male and 69% with identified professional occupational exposure (54% for cork; 69.2% considering only those for which an agent has been identified). Seventy-two percent had locally advanced disease (stage III or IVA-B). The initial treatment was surgery in 77%, and 54% received adjuvant radiotherapy. The median time to progression, progression-free survival, and overall-survival was 2.36 years (95% CI 1.54-8.70), 1.96 years (95% CI 1.43-3.74), and 3.51 years (95% CI 2.33-10.02), respectively. Conclusion: ITAC is an uncommon malignancy that grows silently, which contributes to delayed diagnosis, advanced stage and low survival rates. In our cohort, we observed a high prevalence of cork occupational exposure. This finding may lead to the implementation of protection measures and suggest a potential link to be further studied.info:eu-repo/semantics/publishedVersio

Collateral pial circulation relates to the degree of brain edema on CT 24 hours after ischemic stroke

Background Cerebral edema is frequent in patients with acute ischemic stroke (AIS) who undergo reperfusion therapy and is associated with high mortality. The impact of collateral pial circulation (CPC) status on the development of edema has not yet been determined. Methods We studied consecutive patients with AIS and documented M1-middle cerebral artery (MCA) and/or distal internal carotid artery (ICA) occlusion who underwent reperfusion treatment. Edema was graded on the 24-hour non-contrast computed tomography (NCCT) scan. CPC was evaluated at the acute phase (≤6 hours) by transcranial color-coded Doppler, angiography and/or CT angiography. We performed an ordinal regression model for the effect of CPC on cerebral edema, adjusting for age, baseline National Institutes of Health Stroke Scale, Alberta Stroke Program Early Computed Tomography Score (ASPECTS) on admission, NCCT, parenchymal hemorrhagic transformation at 24 hours and complete recanalization at six hours. Results Among the 108 patients included, 49.1% were male and mean age was 74.2 ± 11.6 years. Multivariable analysis showed a significant association between cerebral edema and CPC status (OR 0.22, 95% CI 0.08-0.59, p = 0.003), initial ASPECTS (OR 0.72, 95% CI 0.57-0.92, p = 0.007) and parenchymal hemorrhagic transformation (OR 23.67, 95% CI 4.56-122.8, p < 0.001). Conclusions Poor CPC is independently associated with greater cerebral edema 24 hours after AIS in patients who undergo reperfusion treatment.info:eu-repo/semantics/publishedVersio

Endothelial Progenitor Cells influence acute and subacute stroke hemodynamics

BACKGROUND: Endothelial Progenitor Cells (EPCs) are a circulating stem cell population with in vivo capacity of promoting angiogenesis after ischemic events. Despite the promising preclinical data, their potential integration with reperfusion therapies and hemodynamic evolution of stroke patients is still unknown. Our aim was to determine the association of EPCs with acute, subacute and chronic hemodynamic features. METHODS: In this prospective study, we included consecutive patients with ages between 18 and 80years and non-lacunar ischemic stroke within the territory of a middle cerebral artery. All patients were subject to hemodynamic evaluation by ultrasound at baseline, seven days and three months. We quantified cerebral blood flow (CBF) and assessed early recanalization and collateral flow. Hemorrhagic transformation was graded in Magnetic Resonance imaging performed at seven days. EPCs were isolated from peripheral venous blood collected in the first 24h and seven days, counted and submitted to functional in vitro tests. RESULTS: We included 45 patients with a median age of 70±10years. The angiogenic and migratory capacities of EPCs were associated with increased collateral flow in the acute stage and day seven CBF, without statistically significant associations with recanalization nor haemorrhagic transformation. The number of EPCs was not associated with any hemodynamic variable. CONCLUSIONS: The functional properties of EPCs are associated with acute and subacute stroke hemodynamics, with no effect on haemorrhagic transformation.info:eu-repo/semantics/publishedVersio

Anatomical characteristics of the styloid process in internal carotid artery dissection: Case-control study

Introduction Pathophysiology of cervical artery dissection is complex and poorly understood. In addition to well-known causative and predisposing factors, including major trauma and monogenic connective tissue disorders, morphological characteristics of the styloid process have been recently recognized as a possible risk factor for cervical internal carotid artery dissection. Aims To study the association of the anatomical characteristics of styloid process with internal carotid artery dissection. Methods Retrospective, multicenter, case-control study of patients with internal carotid artery dissection and age- and sex-matched controls. Consecutive patients with internal carotid artery dissection and controls with ischemic stroke or transient ischemic attack of any etiology excluding internal carotid artery dissection, who had performed computed tomography angiography, diagnosed between January 2010 and September 2016. Two independent observers measured styloid process length and styloid process distance to internal carotid artery. Results Sixty-two patients with internal carotid artery dissection and 70 controls were included. Interobserver agreement was good for styloid process length and styloid process-internal carotid artery distance (interclass correlation coefficient = 0.89 and 0.76, respectively). Styloid process ipsilateral to dissection was longer than left and right styloid process in controls (35.8 ± 14.4 mm versus 30.4 ± 8.9 mm and 30.3 ± 8.2 mm, p = 0.011 and p = 0.008, respectively). Styloid process-internal carotid artery distance ipsilateral to dissection was shorter than left and right distance in controls (6.3 ± 1.9 mm versus 7.2 ± 2.1 mm and 7.0 ± 2.3 mm, p = 0.003 and p = 0.026, respectively). Internal carotid artery dissection was associated with styloid process length (odds ratio = 1.04 mm-1, 95% confidence interval = 1.01-1.08, p = 0.015) and styloid process-internal carotid artery distance (OR = 0.77 mm-1, 95% confidence interval = 0.64-0.92, p = 0.004). Conclusion Longer styloid process and shorter distance between styloid process and cervical internal carotid artery are associated with cervical internal carotid artery dissection.info:eu-repo/semantics/publishedVersio