Electrical asymmetric-flow field-flow fractionation with a multi-detector array platform for the characterization of metallic nanoparticles with different coatings.

Electrical asymmetric-flow field-flow fractionation (EAF4) is a new and interesting analytical technique recently proposed for the characterization of metallic nanoparticles (NPs). It has the potential to simultaneously provide relevant information about size and electrical parameters, such as electrophoretic mobility (µ) and zeta-potential (ζ), of individual NP populations in an online instrumental setup with an array of detectors. However, several chemical and instrumental conditions involved in this technique are definitely influential, and only few applications have been proposed until now. In the present work, an EAF4 system has been used with different detectors, ultraviolet-visible (UV-vis), multi-angle light scattering (MALS), and inductively coupled plasma with triple quadrupole mass spectrometry (ICP-TQ-MS) for the characterization of gold, silver, and platinum NPs with both citrate and phosphate coatings. The behavior of NPs has been studied in terms of retention time and signal intensity under both positive and negative current with results depending on the coating. Carrier composition, particularly ionic strength, was found to be critical to achieve satisfactory recoveries and a reliable measurement of electrical parameters. Dynamic light scattering (DLS) has been used as a comparative technique for these parameters. The NovaChem surfactant mix (0.01%) showed a quantitative recovery (93 ± 1%) of the membrane, but the carrier had to be modified by increasing the ionic strength with 200 µM of Na2CO3 to achieve consistent µ values. However, ζ was one order of magnitude lower in EAF4-UV-vis-MALS than in DLS, probably due to different electric processes in the channel. From a practical point of view, EAF4 technique is still in its infancy and further studies are necessary for a robust implementation in the characterization of NPs.

Intravenous thrombolysis in acute ischemic stroke due to intracranial artery dissection: a single-center case series and a review of literature.

Efficacy and safety of intravenous thrombolysis (IVT) in acute ischemic stroke (AIS) due to intracranial artery dissection (IAD) are currently not established. We aimed to present a single-center experience on IAD-related AIS treated by IVT. We selected all consecutive patients with IAD-related AIS treated by IVT from a prospectively constructed single-center acute stroke registry from 2003 to 2017. We reviewed demographical, clinical and neuroimaging data and recorded hemorrhagic complications, mortality within 7 days and modified Rankin Scale at 3-months. Out of 181 AISs related to cervicocephalic dissections, 10 (5.5%) were due to IAD and five of these patients received IVT. Among these five patients, median age was 62 years; hypertension and dyslipidemia were the most frequent vascular risk factors. IAD locations were distal internal carotid artery, middle cerebral artery (M1), anterior cerebral artery (A2), and, in two cases, the basilar artery. All anterior circulation IADs were occlusive or subocclusive, while the two basilar artery IADs caused arterial stenosis. After IVT, there were no subarachnoid or symptomatic intracranial hemorrhages. One patient had an asymptomatic hemorrhagic infarct type 1. Two patients died within 7 days from ischemic mass effect. The other three patients had favorable clinical outcomes at 3-months. In this small single-center case series of IAD-related AIS, thrombolysis seemed relatively safe. However, IVT efficacy and the likelihood of arterial recanalization are still uncertain in this context. Further studies are needed to assess the safety and efficacy of IVT in these patients.

Simultaneous extraction and preconcentration of monomethylmercury and inorganic mercury using magnetic cellulose nanoparticles.

Magnetite (Fe3O4) nanoparticles were modified with nanocellulose and are showed to be a useful sorbent for magnetic solid-phase extraction of mercury species. Speciation analysis was performed by using gas chromatography coupled to atomic fluorescence detection (GC-pyro-AFS). The magnetic properties of the sorbent make this approach simple and rapid, and the use of a renewable and biodegradable nanomaterial (nanocellulose) makes it environmentally friendly. The factors that affect adsorption (pH value, amount of nanomaterial, time, volume of sample) and desorption (solvent, time) have been optimized. Both desorption and derivatization of mercury species were performed in a single step. This reduces considerably the sample preparation time. Under the optimized conditions, the limits of detection are 4.0 pg mL-1 for monomethylmercury and 5.6 pg mL-1 for inorganic mercury. The repeatability and reproducibility are satisfactory. The method enables inorganic mercury and monomethylmercury to be simultaneously extracted, with preconcentration factors up to 300. The potential interferences of organic matter and/or co-existing ions were also investigated using synthetic waters. The procedure was applied to the analysis of tap water and river water samples with different characteristics from a mercury polluted area (Almadén, Spain). The extraction recoveries ranged from 81 to 98% regardless of the type of water, which demonstrates the applicability of the method. This is the first time that this kind of sorbent is used for trace metal speciation. Graphical abstract Schematic representation of the new composite material (made of Fe3O4 magnetic nanoparticles and cellulose fibers, MCNPs) for the simultaneous extraction and preconcentration of mercury species taking advantage of the magnetic properties of this eco-friendly sorbent.

In-Hospital and Long-Term Prognosis after Spontaneous Intracerebral Hemorrhage among Young Adults Aged 18-65 Years.

BACKGROUND: Spontaneous intracerebral hemorrhage (ICH) accounts for 10%-15% of all strokes and has an estimated annual incidence of 5/100,000 in young adults. Limited data on prognosis after ICH in young adults are available. We aimed to identify prognostic predictors after ICH among adults aged 18-65 years. METHODS: We retrospectively selected all patients with ICH from a prospective single-center registry of adults with first stroke before 65 years between 1997 and 2002. We recorded in-hospital mortality as well as mortality and recurrent stroke after discharge until December 1, 2018. For in-hospital analysis, we compared patients that died in-hospital versus patients discharged alive. For long-term analysis, we compared patients that died in follow-up versus patients still alive. Independent prognostic predictors were identified using multivariate analyses. RESULTS: Among 161 patients included, 24 (14.9%) died in-hospital. Among in-hospital survivors, 5-year survival was 92.0%, 10-year survival 78.1%, and 15-year survival 62.0%. After median follow-up of 17 years, 47.4% of patients died, 18 patients had ischemic stroke, and 6 recurrent ICH. Regarding in-hospital prognosis, coma at admission (OR .02 [.00-.11]) was independent predictor for mortality whereas alcoholic habits (OR 12.32 [1.82-83.30]) was independent predictor for survival. An increasing age (OR 1.08 [1.03-1.12]), higher blood glucose levels (OR 1.01 [1.00-1.01]), and hypertension (OR 2.21 [1.22-4.00]) were independent predictors of long-term mortality after ICH. CONCLUSIONS: Alcoholic habits may influence in-hospital survival after ICH in young adults. Long-term mortality in young adults seems to be lower than in elderly and was predicted by higher blood glucose levels and hypertension.

Magnetic nanoparticles-carbon nanotubes hybrid composites for selective solid-phase extraction of polycyclic aromatic hydrocarbons and determination by ultra-high performance liquid chromatography.

A rapid and reliable method based on magnetic solid-phase extraction (MSPE) and ultra-high performance liquid chromatography (UHPLC-FLD) analysis was developed and validated for the quantitative determination of seven polycyclic aromatic hydrocarbons (PAHs) in water samples. Hybrid composites made up of magnetic nanoparticles (MNPs) and carbon nanotubes (CNTs) were tested as adsorbent materials. The main factors influencing the extraction yields were optimized, namely the amount and type of adsorbent in the adsorption, and the solvent, the type of energy and the time in the desorption step. The selected composite was made up of Fe3O4 and multiwalled (MW)-CNTs. The desorption was carried out with sonication probe and tetrahydrofuran (THF); this solvent makes the method directly compatible with the chromatographic mobile phase and it reduces the analysis time. Under the optimized conditions, the LODs and LOQs achieved were in the range of 0.025-0.73 and 0.04-2.4 ng mL-1, respectively. The calibration curves were linear (R 2 ≥ 0.9936) over the concentration ranges from 1 to 500 ng mL-1. The recoveries of PAHs were from 76.4 ± 1.7 up to 106.5 ± 3.5%. The method was applied to synthetic and real (tap, dam, river and mineral) water samples with different characteristics to evaluate the performance under real conditions.

Astaxanthin and papilioerythrinone in the skin of birds: a chromatic convergence of two metabolic routes with different precursors?

Carotenoids are organic pigments involved in several important physiological functions and may serve as indicators of individual quality in animals. These pigments are only obtained by animals from the diet, but they can be later transformed into other carotenoids by specific enzymatic reactions. The diet of farm-reared and probably wild red-legged partridges (Alectoris rufa) is mainly based on cereals that contain high levels of lutein and zeaxanthin. These two carotenoids are also predominant in internal tissues and blood of red-legged partridges. However, in their integuments, astaxanthin and papilioerythrinone (the last one identified in this work) are mainly present in their free form and esterified with fatty acids. According to available literature about carotenoid metabolism in animals, we propose that astaxanthin (λ max = 478 nm) and papilioerythrinone (λ max = 452-478 nm) are the result of a chromatic convergence of the transformation of dietary zeaxanthin and lutein, respectively. Moreover, the results obtained in this work provide the first identification by liquid chromatography coupled to accurate mass quadrupole time-of-flight mass spectrometer system of papilioerythrinone (m/z 581.3989 [M + H](+)) in the skin (i.e., not feathers) of a vertebrate. Astaxanthin and papilioerythrinone are very close in terms of chemical structure and coloration, and the combination of these two keto-carotenoids is responsible for the red color of the ornaments in red-legged partridges.

Characterization of persistent headache attributed to past stroke.

BACKGROUND: Persistent headache attributed to past stroke (PHAPS) is a controversial entity, recently included in the third edition of the International Classification of Headache Disorders (ICHD-3) despite being described only in retrospective studies. OBJECTIVE: To determine the frequency and characteristics of PHAPS in patients admitted with acute stroke. METHODS: We selected all patients with headache associated with acute stroke (HAAS) from a prospective, single-center registry of patients with acute stroke admitted to a Neurology ward between November 2018 and December 2019. We analyzed demographic, clinical, and neuroimaging data. We assessed the follow-up with a phone call questionnaire at 6 to 12 months. RESULTS: Among 121 patients with acute stroke, only 29 (24.0%) had HAAS. From these, 6 (5.0%) were lost to follow-up. In total, 23 (20.0%) patients answered the 6- to 12-month follow-up questionnaire and were included in this study. The median age of the sample was 53 years (interquartile range [IQR]: 38-78 years), and there was no sex predominance. Of the 10 patients (8,3%) that had persistent headache, 8 (6.6%) suffered from previous chronic headaches; however, they all mentioned a different kind of headache, and 1 (0,8%) probably had headache secondary to medication. CONCLUSIONS: In the present study, only 10 out of 121 stroke patients (8.3%) referred persistent headache at the 6- to 12-month follow-up, but the majority already suffered from previous chronic headache, which raises the question that the actual prevalence of PHAPS may be lower than previously reported.

ANTECEDENTES: A cefaleia persistente atribuída a acidente vascular cerebral (AVC) prévio é uma entidade controversa, recentemente incluída na terceira edição da Classificação Internacional de Transtornos da Cefaleia (International Classification of Headache Disorders, ICHD-3), apesar de descrita apenas em estudos restrospectivos. OBJETIVO: Determinar a frequência e as características do acidente vascular cerebral prèvio em doentes admitidos com AVC agudo. MéTODOS: Selecionamos todos os doentes com cefaleia associada a AVC agudo de um registro unicêntrico e prospectivo de doentes admitidos no serviço de Neurologia entre novembro de 2018 e dezembro de 2019. Analisamos dados demográficos, clínicos e imagiológicos. Reavaliamos aos 6 a 12 meses por questionário telefónico. RESULTADOS: Entre os 121 doentes admitidos com AVC agudo, apenas 29 (24,0%) tinham cefaleia associada a AVC agudo. Destes, 6 (5,0%) perderam-se no seguimento. Ao todo, 23 (20,0%) responderam ao questionário e foram incluídos. A idade mediana foi de 53 anos (intervalo interquartílico [IIQ]: 38­78 anos), e não houve predominância de gênero. Dos 10 doentes (8,3%) que apresentam cefaleia persistente, 8 (6,6%) tinham histórico de cefaleia; no entanto todos mencionaram um tipo diferente de cefaleia, e 1 (0,8%) provavelmente tinha cefaleia secundária a medicação. CONCLUSõES: Neste estudo, apenas 10 em 121 doentes (8,3%) mencionaram cefaleia persistente aos 6 a 12 meses de seguimento, mas a maioria sofria de cefaleia prévia, pelo que a real prevalência de acidente vascular cerebral prèvio pode ser inferior à descrita nos estudos realizados até a data.

Pediatric cerebral sinus venous thrombosis: clinical characterization of a Portuguese cohort.

INTRODUCTION: Pediatric cerebral sinus venous thrombosis (CSVT) is a rare entity. Risk factors differ from the adults, and treatment is not consensual. With this work, we aimed to characterize a pediatric cohort from two Portuguese tertiary centers. METHODS: All patients under 18 years old with confirmed CSVT admitted between 2006 and 2019 were retrospectively included. Demographics, clinical presentation, workup, and follow-up were evaluated. RESULTS: Fifty-three patients were included, 29 were male (54.7%). Median age was 5 years (IQR 11.08, range 0-17 years old). Headache, seizures and impairment of consciousness were the most frequent manifestations. A risk factor was identified in 90.6% (n = 48), mostly infections (43.8%; n = 21). CNS complications were comprised of hemorrhage, venous infarction, hydrocephalus and edema. Treatment included anticoagulation in 36 patients (67.9%), and there were no recurrences on follow-up. Prognosis was favorable, with most patients presenting no or only slight disability comparing to same age and sex children, on the follow-up. DISCUSSION: In this cohort, impairment of consciousness was the most frequent clinical presentation and infections were the most frequent risk factors. The outcome was mainly favorable, with most patients presenting none or mild disability and without recurrences on follow-up. Studies are needed to define the criteria for anticoagulation and its recommended duration in children.

Rapid assessment of silver nanoparticle migration from food containers into food simulants using a qualitative method.

Migration of silver nanoparticles (AgNPs) from food containers (FCs) has been assessed for the first time using a screening method previously validated. Migration was evaluated using water and 3% acetic acid as food simulants (FSs), from 20 to 70 °C at contact times of 2 h and 10 days. Total and migrated Ag were determined by inductively coupled plasma-mass spectrometry (ICP-MS) in the FCs and FSs, respectively. Then, the screening method was validated, and probability of detection (POD) curves were constructed in both FSs to characterize the response to AgNPs. The results provided by the present screening method showed no release of AgNPs. The FSs in contact with FCs were spiked at levels above, inside and below the unreliability region, with a reliability rate (RLR) of 0.90. Asymmetric flow field flow fractionation coupled to inductively coupled plasma mass-spectrometry (AF4-ICP-MS) was used for confirmative analyses.

Screening-confirmation strategy for nanomaterials involving spectroscopic analytical techniques and its application to the control of silver nanoparticles in pastry samples.

The full characterization of nanomaterials (NMs), which requires a range of different and expensive equipment, is not always necessary to meet certain demands of information. Qualitative analytical methods are ideal alternatives when only a piece of information is required. In this work, a qualitative method for the screening of NMs has been developed and statistically validated for the first time, with silver nanoparticles (AgNPs) as a proof of concept. It is based on the generation of chemiluminescence of the luminol/Ag+ system in alkaline media in the presence of AgNPs. Measurements are obtained in a short time with a simple instrument. Probability of detection (POD) curves were constructed at three cut-off values next to the limit of detection of the chemiluminescent method. The unreliability region (UR) was from 0.50 to 1.82 µg L-1. Currently, no regulation on AgNPs exists, but the present method was successfully tested for a hypothetical threshold of 2.5 µg L-1 of 40 nm AgNPs. The method was applied to silver colored pearls, with silver (E-174) or aluminum (E-173) coating, used for decoration of pastry. Performance parameters such as false negative and positive rates as well as specificity, sensitivity and reliability rates were calculated for validation. The results of the screening method were confirmed by asymmetric flow field flow fractionation coupled to inductively coupled plasma mass spectrometry (AF4-ICP-MS). The proposed screening method is simple, fast, economic, and easy to transfer to routine laboratories in the field of food safety.

Designing and Evaluating the Usability of a Machine Learning API for Rapid Prototyping Music Technology.

To better support creative software developers and music technologists' needs, and to empower them as machine learning users and innovators, the usability of and developer experience with machine learning tools must be considered and better understood. We review background research on the design and evaluation of application programming interfaces (APIs), with a focus on the domain of machine learning for music technology software development. We present the design rationale for the RAPID-MIX API, an easy-to-use API for rapid prototyping with interactive machine learning, and a usability evaluation study with software developers of music technology. A cognitive dimensions questionnaire was designed and delivered to a group of 12 participants who used the RAPID-MIX API in their software projects, including people who developed systems for personal use and professionals developing software products for music and creative technology companies. The results from questionnaire indicate that participants found the RAPID-MIX API a machine learning API which is easy to learn and use, fun, and good for rapid prototyping with interactive machine learning. Based on these findings, we present an analysis and characterization of the RAPID-MIX API based on the cognitive dimensions framework, and discuss its design trade-offs and usability issues. We use these insights and our design experience to provide design recommendations for ML APIs for rapid prototyping of music technology. We conclude with a summary of the main insights, a discussion of the merits and challenges of the application of the CDs framework to the evaluation of machine learning APIs, and directions to future work which our research deems valuable.

Stiff person spectrum disorders: An illustrative case series of their phenotypic and antibody diversity.

Stiff person spectrum disorders (SPSD) are a broad group of immune-mediated disorders. Clinical presentations include classical stiff person syndrome (SPS), focal SPS, and progressive encephalomyelitis with rigidity and myoclonus (PERM). The most frequently associated antibodies are anti-GAD65, anti-GlyR, anti-amphiphysin, and anti-DPPX. Immunotherapy is the primary treatment modality. We present an illustrative case series of three patients: anti-GlyR antibody-mediated PERM presenting as rapidly progressive dementia; anti-amphiphysin antibody-mediated SPS; and SPS presentation with anti-Zic4 antibodies, spasmodic laryngeal stridor and fluctuating eyelid ptosis. Clinical characteristics, CSF findings, neurophysiological features, adequate immunological assays and a high suspicion index are essential for prompt diagnosis and management.

Analytical metrology for nanomaterials: Present achievements and future challenges.

Nanoscience and nanotechnology have emerged in recent years as revolutionary trends in almost all fields of activity. Their impact has taken place in the analytical science, too. Firstly, because the use of nanomaterials as analytical tools is more and more frequent and secondly, because the analytical control of nanomaterials in a wide variety of samples is required. In both aspects, analytical metrology for nanomaterials is involved as the scientific discipline responsible for providing reliable information (based on experimental measurements) to end users. This review presents a general view of the present achievements and the future challenges of analytical metrology for nanomaterials. Selected references and a critical discussion are reported for illustrating this important role of the metrology applied to nano-world.

Magnetic cellulose nanoparticles as sorbents for stir bar-sorptive dispersive microextraction of polychlorinated biphenyls in juice samples.

Magnetic cellulose nanoparticles (MCNPs) were used for the first time as sorbents for stir bar-sorptive dispersive microextraction (SBSDME). The main experimental parameters involved in the SBSDME process that affect extraction (i.e. amount of MCNPs, ionic strength, pH, extraction and back-extraction time) were investigated. The method was applied to the determination of nine polychlorinated biphenyls (PCBs) in fruit juice samples by gas chromatography-mass spectrometry (GC-MS). Under the optimized conditions, a good linearity was obtained in a concentration range of 10-1000 ng mL-1 with determination coefficients over 0.9945. Limits of detection and quantification for all target PCBs were in the range 2.1-54 ng L-1 and 7.0-180 ng L-1, respectively. Intra-day precision ranged from 1.7% to 8.8% and inter-day precision from 3.4% to 9.3% RSD. The enrichment factors of the analytes were from 74.6 to 98.2. The MCNPs can be reused up to 5 times. The method was applied to commercial orange and pineapple juices (n = 5), where concentrations were below the limits of detection. Recoveries from 70.4 to 108.0% were obtained by applying the method for the analysis of spiked fruit juice samples at 1 and 2 ng mL-1 concentration levels. The use of cellulose makes this approach environmentally friendly and the magnetism of the resulting sorbent in conjunction with SBSDME provides ease of handling and saving of time.

Efficacy and safety of endovascular treatment in acute ischemic stroke due to cervical artery dissection: A 15-year consecutive case series.

BACKGROUND: Limited observational data are available on endovascular treatment in acute ischemic stroke due to cervical artery dissection. Three studies comparing endovascular treatment with standard medical therapy or intravenous thrombolysis in cervical artery dissection-related acute ischemic stroke did not demonstrate superiority of endovascular treatment. Efficacy and the choice of endovascular treatment technique in this setting remain to be established. AIMS: To assess the potential efficacy and safety of endovascular treatment compared to intravenous thrombolysis alone or to no revascularization treatment in our center. METHODS: We selected all consecutive patients with cervical artery dissection-related acute ischemic stroke and intracranial occlusion from the Acute STroke Registry and Analysis of Lausanne between 2003 and 2017. We compared clinical and neuroimaging data of patients treated by endovascular treatment versus patients receiving intravenous thrombolysis or patients without revascularization treatment. Safety analysis included symptomatic intracranial hemorrhage, major radiological hemorrhages (parenchymal hematoma 1, parenchymal hematoma 2, and subarachnoid hemorrhage) and mortality within seven days. We assessed favorable clinical outcome (modified Rankin Scale 0-2) at three months using a binary logistic regression model. RESULTS: Of the 109 patients included, 24 had endovascular treatment, 38 received intravenous thrombolysis alone, and 47 had no revascularization treatment. Endovascular treatment patients had a higher rate of recanalization at 24 h. Major radiological hemorrhages occurred more often in endovascular treatment patients (all with bridging therapy) than in patients without revascularization treatment (p = 0.026), with no differences in symptomatic intracranial hemorrhage or mortality within seven days. Favorable clinical outcome at three months did not differ between groups (endovascular treatment versus intravenous thrombolysis p = 0.407; endovascular treatment versus no revascularization treatment p = 0.580). CONCLUSIONS: In this single-center cohort of cervical artery dissection-related acute ischemic stroke with intracranial occlusion, endovascular treatment with prior intravenous thrombolysis may increase the risk of major radiological but not symptomatic intracranial hemorrhage. Despite the lack of clear superiority in our cohort, endovascular treatment should currently not be withheld in these patients.

Ionic liquid dispersive liquid-liquid microextraction combined with LC-UV-Vis for the fast and simultaneous determination of cortisone and cortisol in human saliva samples.

Ionic liquid dispersive liquid-liquid microextraction (IL-DLLME) was used for the first time for the extraction and preconcentration of cortisone and cortisol from human saliva samples. This approach allows the determination of both compounds by liquid chromatography (LC) with ultra-violet/visible (UV/Vis) detection at physiological levels. The IL 1-butyl-3-methylimidazolium hexafluorophosphate [C4MIM][PF6] and methanol (MeOH) were used as extraction and dispersive solvents, respectively. The parameters that affect extraction (ionic strength, pH, amount of IL, volume of dispersive solvent, vortex and centrifugation time) were optimized. Limits of detection were 0.11 (cortisone) and 0.16 µg L-1 (cortisol) and enrichment factors of 5.0 (cortisol) and 6.3 (cortisone) were achieved. Recoveries from 83.3 ± 1.6 to 115.8 ± 3.0% were obtained for the extraction of the target analytes in spiked human saliva samples. Intraday and interday precision, expressed as relative standard deviation, was below 4.2 and 7.8% for cortisone and cortisol, respectively. The method was successfully applied to the determination of cortisone and cortisol in saliva from healthy volunteers (n = 9) in the morning and in the evening. The method is simple, faster, and more environmentally friendly than the current ones.

Carbon nanotubes magnetic hybrid nanocomposites for a rapid and selective preconcentration and clean-up of mercury species in water samples.

Hybrid nanocomposites based on Fe3O4 magnetic nanoparticles (MNPs) coated with different types of carbon nanotubes (CNTs) have been studied for the first time as sorbent materials for magnetic solid phase extraction (MSPE) for mercury speciation analysis. Monomethylmercury (MMHg) was the target mercury species in water samples and the adsorption and desorption processes were optimized based on this species. Single-walled CNT-MNP showed higher adsorption capacity than double-walled or multi-walled CNTs. Then, the magnetic sorbent was retrieved with an external magnet and MMHg was selectively desorbed from it with dichloromethane (DCM) in two steps with vortex agitation. Inorganic mercury was removed during the desorption stage. The rapid adsorption and desorption equilibrium, the magnetic separation of the sorbent, and the simple and fast synthesis of CNT-MNPs without any additional modification of the CNTs simplified and shortened the extraction procedure. The extract was submitted to derivatization of the mercury species by ethylation (with an optional nitrogen stream evaporation of the organic phase) and injection into a gas chromatograph coupled to an atomic fluorescence detector (GC-pyro-AFS). The overall procedure provides the preconcentration of MMHg up to 150 times and the removal of inorganic mercury at the same time. The procedural limits of detection (LOD) and quantification (LOQ) were 5.4 and 17.9pgmL-1, respectively. Moreover, magnetic nanocomposites can be reused at least 7 times without losing their efficiency. The methodology was validated in tap, dam and river water samples to evaluate the performance under real conditions with recoveries from 79% to 97% of spiked MMHg.

[The 1918 influenza epidemic in Bogota]. / La pandemia de gripa de 1918 en Bogotá.

The influenza pandemic of 1918-1919 was one of the most severe recorded in Colombia. There were 1,900 deaths in the capital, Bogota. The poor and unprotected were the most affected. Care of victims was the responsibility of the Junta de Socorros, a private body. Based on different primary sources (mostly official documents, Junta de Socorros reports, newspapers, and medical journals) this article explores how the 1918 influenza pandemic altered Bogotá's social dynamics, with particular attention to its impact on disease and mortality rates and to an analysis of how the city's sanitary conditions and political-institutional decisions and the reactions of different social sectors influenced the response of this human community to the pandemic.

Characterization of persistent headache attributed to past stroke / Caracterização da cefaleia persistente atribuída a acidente vascular cerebral prévio

Abstract Background Persistent headache attributed to past stroke (PHAPS) is a controversial entity, recently included in the third edition of the International Classification of Headache Disorders (ICHD-3) despite being described only in retrospective studies. Objective To determine the frequency and characteristics of PHAPS in patients admitted with acute stroke. Methods We selected all patients with headache associated with acute stroke (HAAS) from a prospective, single-center registry of patients with acute stroke admitted to a Neurology ward between November 2018 and December 2019. We analyzed demographic, clinical, and neuroimaging data. We assessed the follow-up with a phone call questionnaire at 6 to 12 months. Results Among 121 patients with acute stroke, only 29 (24.0%) had HAAS. From these, 6 (5.0%) were lost to follow-up. In total, 23 (20.0%) patients answered the 6- to 12-month follow-up questionnaire and were included in this study. The median age of the sample was 53 years (interquartile range [IQR]: 38-78 years), and there was no sex predominance. Of the 10 patients (8,3%) that had persistent headache, 8 (6.6%) suffered from previous chronic headaches; however, they all mentioned a different kind of headache, and 1 (0,8%) probably had headache secondary to medication. Conclusions In the present study, only 10 out of 121 stroke patients (8.3%) referred persistent headache at the 6- to 12-month follow-up, but the majority already suffered from previous chronic headache, which raises the question that the actual prevalence of PHAPS may be lower than previously reported.

Resumo Antecedentes A cefaleia persistente atribuída a acidente vascular cerebral (AVC) prévio é uma entidade controversa, recentemente incluída na terceira edição da Classificação Internacional de Transtornos da Cefaleia (International Classification of Headache Disorders, ICHD-3), apesar de descrita apenas em estudos restrospectivos. Objetivo Determinar a frequência e as características do acidente vascular cerebral prèvio em doentes admitidos com AVC agudo. Métodos Selecionamos todos os doentes com cefaleia associada a AVC agudo de um registro unicêntrico e prospectivo de doentes admitidos no serviço de Neurologia entre novembro de 2018 e dezembro de 2019. Analisamos dados demográficos, clínicos e imagiológicos. Reavaliamos aos 6 a 12 meses por questionário telefónico. Resultados Entre os 121 doentes admitidos com AVC agudo, apenas 29 (24,0%) tinham cefaleia associada a AVC agudo. Destes, 6 (5,0%) perderam-se no seguimento. Ao todo, 23 (20,0%) responderam ao questionário e foram incluídos. A idade mediana foi de 53 anos (intervalo interquartílico [IIQ]: 38-78 anos), e não houve predominância de gênero. Dos 10 doentes (8,3%) que apresentam cefaleia persistente, 8 (6,6%) tinham histórico de cefaleia; no entanto todos mencionaram um tipo diferente de cefaleia, e 1 (0,8%) provavelmente tinha cefaleia secundária a medicação. Conclusões Neste estudo, apenas 10 em 121 doentes (8,3%) mencionaram cefaleia persistente aos 6 a 12 meses de seguimento, mas a maioria sofria de cefaleia prévia, pelo que a real prevalência de acidente vascular cerebral prèvio pode ser inferior à descrita nos estudos realizados até a data.

Dietary supplementation with omega-3 fatty acids and oleate enhances exercise training effects in patients with metabolic syndrome.

OBJECTIVE: We studied the effects of exercise training alone or combined with dietary supplementation of omega-3 polyunsaturated fatty acids (Ω-3PUFA) and oleate on metabolic syndrome (MSyn) components and other markers of cardiometabolic health. METHODS: Thirty-six patients with MSyn underwent 24 weeks of high-intensity interval training. In a double-blind randomized design, half of the group ingested 500 mL/day of semi-skim milk (8 g of fat; placebo milk) whereas the other half ingested 500 mL/day of skim milk enriched with 275 mg of Ω-3PUFA and 7.5 g of oleate (Ω-3 + OLE). RESULTS: Ω-3 + OLE treatment elevated 30% plasma Ω-3PUFA but not significantly (P = 0.286). Improvements in VO2peak (12.8%), mean blood pressure (-7.1%), waist circumference (-1.8%), body fat mass (-2.9%), and trunk fat mass (-3.3%) were similar between groups. However, insulin sensitivity (measured by intravenous glucose tolerance test), serum concentration of C-reactive protein, and high-density lipoprotein improved only in the Ω-3 + OLE group by 31.5%, 32.1%, and 10.3%, respectively (all P < 0.05). Fasting serum triacylglycerol, glucose, and plasma fibrinogen concentrations did not improve in either group after 24 weeks of intervention. CONCLUSIONS: Diet supplementation with Ω-3PUFA and oleate enhanced cardiometabolic benefits of intense aerobic exercise training in patients with MSyn.