Paramagnetic Singularities of the Orbital Magnetism in Graphene with a Moiré Potential.

The recent detection of the singular diamagnetism of Dirac electrons in a single graphene layer paved a new way of probing 2D quantum materials through the measurement of equilibrium orbital currents which cannot be accessed in usual transport experiments. Among the theoretical predictions is an intriguing orbital paramagnetism at saddle points of the dispersion relation. Here we present magnetization measurements in graphene monolayers aligned on hexagonal boron nitride crystals. Besides the sharp diamagnetic McClure response at the Dirac point, we detect extra diamagnetic singularities at the satellite Dirac points of the moiré lattice. Surrounding these diamagnetic satellite peaks, we also observe paramagnetic peaks located at the chemical potential of the saddle points of the graphene moiré band structure and relate them to the presence of van Hove logarithmic singularities in the density of states. These findings reveal the long ago predicted anomalous paramagnetic orbital response in 2D systems when the Fermi energy is tuned to the vicinity of saddle points.

Toxocariasis in migrant children: A 6 years' experience in a reference pediatric unit in Spain.

BACKGROUND: Toxocariasis is a worldwide distributed zoonosis that affects characteristically children. Clinical presentation is highly variable, often asymptomatic, and treatment duration is controversial. METHODS: A retrospective descriptive study (January 2014-December 2019) was performed in a referral Unit for Pediatric Tropical Diseases. Patients younger than 18 years of age diagnosed with toxocariasis were included. RESULTS: Out of 931 children screened for toxocariasis, 49 (5.3%) were seropositive. The median age was 11.0 years, 55.1% male and 30.6% referred contact with puppies. Overall, 34.7% were Latin-American, 24.5% Asiatic, 20.4% European, and 20.4% African. Only 34.7% presented symptoms, gastrointestinal the most common (52.9%). The 57.1% of children presented eosinophilia and 50% elevated total IgE. Most cases (95.9%) corresponded to covert toxocariasis. All children were treated with albendazole for 5, 14 or 21 days, and 4 children required a second course. Follow-up data were available in 32 children (65.3%) for a median of 7 months, showing a progressive decline in eosinophils, IgE-titers and ELISA optical density. CONCLUSION: Toxocariasis is mostly asymptomatic in children and eosinophilia is not always present. Serological tests should be included in migrant health screening and in the diagnostic assessment of eosinophilia. Eosinophil count, IgE-titers and ELISA optical-density could be useful during follow-up.

Continuous Positive Airway Pressure vs. High Flow Nasal Cannula in children with acute severe or moderate bronchiolitis. A systematic review and Meta-analysis.

OBJECTIVE: To compare the safety and effectiveness of Continuous Positive Airway Pressure (CPAP) vs. High Flow Nasal Cannula (HFNC) to prevent therapeutic failure and the need of invasive ventilation in children with acute moderate-severe bronchiolitis. DESIGN: A systematic review and meta-analysis. SETTING: Medline, Embase, Lilacs, Cochrane and gray literature (May 2020) was performed. PARTICIPANTS: Randomized clinical trials patients with moderate to severe bronchiolitis. MAIN VARIABLES: Therapeutic failure, need for invasive ventilation, adverse events, length of PCCU and of hospital stay. INTERVENTION: The quality of the studies was assessed with the Cochrane risk and bias tool. We conducted meta-analysis using fixed effect model and random effects model. RESULTS: Three RCTs were included. Showed less risk of therapeutic failure with CPAP compared with HFNC (RR=0.7; 95%CI 0.5-0.99) developed hours later in patients with CPAP (MD=3.16; 95%CI 1.55-4.77). We did not find differences in other outcomes, such as need of invasive ventilation (RR=0.60; 95%CI 0.25-1.43), apnea (RR=0.40; 95%CI 0.08-1.99), or number of days in the intensive care unit (MD=0.02; 95%CI -0.38 to 0.42), and length of hospitalization (MD=-1.00; 95%IC -2.66 to 0.66). Adverse events (skin lesions) were more common with CPAP (RR 2.47; 95%CI 1.17-5.22). CONCLUSIONS: In moderate/severe bronchiolitis CPAP demonstrated a lower risk of therapeutic failure and a longer time to failure. But more adverse events like nasal injury. There were no differences in other variables.

Continuous Positive Airway Pressure vs. High Flow Nasal Cannula in children with acute severe or moderate bronchiolitis. A systematic review and Meta-analysis / Presión positiva continua en vía aérea (CPAP) vs. Cánula de alto flujo (CAF) en lactantes con bronquiolitis aguda moderada y grave. Revisión sistemática de la literatura y meta-análisis

Objective: To compare the safety and effectiveness of Continuous Positive Airway Pressure (CPAP) vs. High Flow Nasal Cannula (HFNC) to prevent therapeutic failure and the need of invasive ventilation in children with acute moderate-severe bronchiolitis.Design: A systematic review and meta-analysis.SettingMedline, Embase, Lilacs, Cochrane and gray literature (May 2020) was performed.ParticipantsRandomized clinical trials patients with moderate to severe bronchiolitis.Main variablesTherapeutic failure, need for invasive ventilation, adverse events, length of PCCU and of hospital stay.InterventionThe quality of the studies was assessed with the Cochrane risk and bias tool. We conducted meta-analysis using fixed effect model and random effects model.Results: Three RCTs were included. Showed less risk of therapeutic failure with CPAP compared with HFNC (RR=0.7; 95%CI 0.5–0.99) developed hours later in patients with CPAP (MD=3.16; 95%CI 1.55–4.77). We did not find differences in other outcomes, such as need of invasive ventilation (RR=0.60; 95%CI 0.25–1.43), apnea (RR=0.40; 95%CI 0.08–1.99), or number of days in the intensive care unit (MD=0.02; 95%CI −0.38 to 0.42), and length of hospitalization (MD=−1.00; 95%IC −2.66 to 0.66). Adverse events (skin lesions) were more common with CPAP (RR 2.47; 95%CI 1.17–5.22).Conclusion: sIn moderate/severe bronchiolitis CPAP demonstrated a lower risk of therapeutic failure and a longer time to failure. But more adverse events like nasal injury. There were no differences in other variables (AU)

Objetivo: Comparar la seguridad y la efectividad de la presión positiva continúa en la vía aérea (CPAP) y la cánula nasal de oxígeno de alto flujo (OAF) para prevenir el fracaso terapéutico y la necesidad de ventilación mecánica invasiva en niños con bronquiolitis aguda moderada y grave.Diseño: Revisión sistemática y metaanálisis.ÁmbitoBúsqueda en Medline, Embase, Lilacs, Cochrane y literatura gris (hasta mayo 2020).ParticipantesEnsayos clínicos aleatorizados en pacientes con bronquiolitis aguda moderada-grave.IntervencionesLa calidad de los estudios se evaluó utilizando la escala de riesgo de sesgos de Cochrane y se realizó un metaanálisis usando modelo de efectos fijos y de efectos aleatorios.VariablesFracaso terapéutico, necesidad de ventilación invasiva, eventos adversos, estancia en la UCIP y en hospitalización.Resultados: Tres estudios fueron incluidos. Evidenciamos menor riesgo de fracaso terapéutico en los pacientes con CPAP comparados con CAF (RR: 0,7; IC 95%: 0,5-0,99), y este se desarrolló más tarde en los pacientes con CPAP (MD: 3,16; IC 95%: 1,55-4,77). No hubo diferencias en otras variables, como la necesidad de ventilación invasiva (RR: 0,60; IC 95%: 0,25-1,43), apnea (RR: 0,40; IC 95%: 0,08-1,99), estancia en la UCIP (MD: 0,02; IC 95%: −0,38-0,42) y en hospitalización (MD: −1,00; IC 95%: −2,66-0,66). Los eventos adversos (lesiones en piel) fueron más comunes en CPAP (RR: 2,47; IC 95%: 1,17-5,22).Conclusiones: En bronquiolitis moderada y grave el CPAP demostró menor riesgo de fracaso terapéutico y una aparición más tardía, pero más eventos adversos (lesiones en piel). No encontramos diferencias en otras variables (AU)

Detection of graphene's divergent orbital diamagnetism at the Dirac point.

The electronic properties of graphene have been intensively investigated over the past decade. However, the singular orbital magnetism of undoped graphene, a fundamental signature of the characteristic Berry phase of graphene's electronic wave functions, has been challenging to measure in a single flake. Using a highly sensitive giant magnetoresistance (GMR) sensor, we have measured the gate voltage­dependent magnetization of a single graphene monolayer encapsulated between boron nitride crystals. The signal exhibits a diamagnetic peak at the Dirac point whose magnetic field and temperature dependences agree with long-standing theoretical predictions. Our measurements offer a means to monitor Berry phase singularities and explore correlated states generated by the combined effects of Coulomb interactions, strain, or moiré potentials.

Liver transplant with controlled donors after circulatory death with normothermic regional perfusion and brain dead donors: A multicenter cohort study of transfusion, one-year graft survival and mortality.

BACKGROUND: Controlled donation after circulatory death (cDCD) has expanded the donor pool for liver transplantation (LT). However, transfusion requirements and perioperative outcomes should be elucidated. The aim of this multicenter study was to assess red blood cell (RBC) transfusions, one-year graft and patient survival after LT after cDCD with normothermic regional perfusion (NRP) compared with donors after brain death (DBD). METHODS: 591 LT carried out in ten centers during 2019 were reviewed. Thromboelastometry was used to manage coagulation and blood product transfusion in all centers. Normothermic regional perfusion was the standard technique for organ recovery. RESULTS: 447 patients received DBD and 144 cDCD with NRP. Baseline MCF Extem was lower in the cDCD group There were no differences in the percentage of patients (63% vs. 61% p = 0.69), nor in the number of RBC units transfused (4.7 (0.2) vs 5.5 (0.4) in DBD vs cDCD, p = 0.11. Twenty-six patients (6%) died during admission for LT in the DBD group compared with 3 patients (2%) in the cDCD group (p = 0.15). To overcome the bias due to a worse coagulation profile in cDCD recipients, matched samples were compared. No differences in baseline laboratory data, or in intraoperative use of RBC or one-year outcome data were observed between DBD and cDCD recipients. CONCLUSIONS: cDCD with NRP is not associated with increased RBC transfusion. No differences in graft and patient survival between cDCD and DBD were found. Donors after controlled circulatory death with NRP can increasingly be utilized with safety, improving the imbalance between organ donors and the ever-growing demand.

Intestinal giardiasis in children: Five years' experience in a reference unit.

BACKGROUND: Giardiasis is highly prevalent in children and is often mildly symptomatic. First-line treatment is metronidazole, but treatment failure is not uncommon. We describe a paediatric series, to identify risk factors for treatment failure and to analyse the safety and effectiveness of other treatment strategies. METHODS: Retrospective observational study, including children diagnosed with giardiasis from 2014 to 2019. Diagnosis was based on direct visualisation by microscopy after concentration using an alcohol-based fixative, antigen detection and/or DNA detection by polymerase chain reaction in stool. Treatment failure was considered when GI was detected 4 weeks after treatment. RESULTS: A total of 120 patients were included, 71.6% internationally adopted, median age 4.2 (2.3-7.3) years. Only 50% presented with symptoms, mainly diarrhoea (35%) and abdominal pain (14.1%); co-parasitism was frequent (45%). First-line treatment failure after a standard dose of metronidazole was 20%, lowering to 8.3% when a higher dose was administered (p < 0.001). Quinacrine was administered in 10 patients, with 100% effectiveness. Children <2 years were at higher risk of treatment failure (OR 3.49; 95% CI 1.06-11.53; p = 0.040). CONCLUSIONS: In children with giardiasis, treatment failure is frequent, especially before 2 years of age. Quinacrine can be considered as a second-line treatment. After treatment, eradication should be confirmed.

Tratamiento endoscópico de lesiones quísticas supratentoriales en pediatría / Endoscopic treatment of supratentorial cystic lesions in pediatrics

Introducción: La endoscopía neuroquirúrgica es una técnica mínimamente invasiva, utilizada desde principios del siglo XX para dar solución a las patologías localizadas en el sistema ventricular. En la actualidad las indicaciones de esta técnica se han ampliado notablemente. El objetivo de este trabajo consiste en presentar el tratamiento endoscópico de quistes cerebrales supratentoriales de diferentes etiologías en pediatría. Materiales y métodos: Se realizó un estudio transversal retrospectivo, desde enero de 2016 hasta diciembre de 2019, de pacientes pediátricos con lesiones quísticas supratentoriales tratados endoscópicamente en el Hospital de Niños de La Plata. Para definir el éxito se utilizó la clasificación en 5 grados de Ross et al. Resultados: Se practicaron 14 procedimientos en 12 pacientes, con edades comprendidas entre los 2 meses y los 9 años. Del total, 6 fueron quistes intraventriculares, 3 quistes de línea media, 5 quistes paraventriculares. Todos presentaban algún signo o síntoma al momento de la consulta, predominando entre ellos la alteración del estado neurológico y los vómitos. Luego de practicarse la fenestración endoscópica, presentaron una evolución clínica favorable en 12 de los 14 procedimientos y una mejoría en al menos un criterio imagenológico en 10 del total de los procedimientos.Basados en la categorización de Ross et al. se obtuvo un grado I en el 57% de los casos, lo que implica una mejoría completa permanente. La tasa de complicación global fue del 7%, presentando en solo un caso infección post endoscopia. Conclusión: La neuroendoscopía debería ser considerada como una opción de primera línea para el tratamiento en las lesiones quísticas supratentoriales. Demostró ser un método poco invasivo, con el cual se obtuvieron buenos resultados y una baja tasa de complicaciones.

Introduction: Neurosurgical endoscopy is a minimally invasive technique, used since the beginning of the 20th century to solve pathologies localized in the ventricular system. Currently the indications for this technique have been greatly expanded. The objective of this work is to present the endoscopic treatment of supratentorial brain cysts of different etiologies in pediatrics. Material and methods: We carried out a retrospective cross-sectional study, from January 2016 to December 2019, of pediatric patients with supratentorial cystic lesions treated endoscopically at the Hospital de Niños of La Plata City. To define success, we used the 5-degree classification of Ross et al. Results: 14 procedures were performed in 12 patients, aged between 2 months and 9 years. Of the total, 6 were intraventricular cysts, 3 midline cysts, 5 paraventricular cysts. All presented any signs or symptoms at the time of the consultation, prevailing among them the alteration of the neurological state and vomiting. After endoscopic fenestration was performed, they presented a favorable clinical evolution in 12 of the 14 procedures and an improvement in at least one imaging criterion in 10 of all procedures. Based on the categorization of Ross et al. we obtained a grade I in 57% of the cases, which implies a permanent complete improvement. The overall complication rate was 7%, presenting post-endoscopy infection in only one case. Conclusion: Neuroendoscopy should be considered as a first-line option for the treatment of supratentorial cystic lesions. It proved to be a non-invasive method, with which we obtained good results and a low complication rate

Lavado endoscópico con colocación de catéter trans acueducto de Silvio en paciente lactante con ventriculitis de difícil manejo / Endoscopic lavage with placement of a trans-aqueduct of Silvio catheter in a nursing patient with difficult-to-manage ventriculitis

Introducción: La ventriculitis representa una emergencia infectológica, generalmente asociada a un procedimiento neuroquirúrgico. La incidencia es desconocida debido a la variación de los criterios diagnóstico. Descripción del caso: Presentamos una paciente de sexo femenino de 6 meses de edad con antecedente de hidrocefalia post hemorrágica, con diagnóstico de ventriculitis por Enterobacter complex asociada a sistema de derivación ventrículo peritoneal (DVP) de difícil manejo. La misma realizó tratamiento combinado de antibiótico con Meropenem y Colistin endovenoso e intraventricular asociado a tratamiento endoscópico que consistió en lavados, aspiración del contenido purulento intraventricular, tercer ventriculostomía endoscópica (TVE), coagulación bilateral del plexo coroideo y acueductoplastia con colocación de catéter de derivación ventricular externa (DVE) entre el tercer y el cuarto ventrículo con el objetivo de mantener la permeabilidad de la misma y de esta manera asegurar la llegada de antibiótico intraventricular al cuarto ventrículo. Discusión: La ventriculitis se asocia a múltiples complicaciones y una elevada tasa de morbi-mortalidad. El tratamiento de las ventriculitis de difícil manejo, es aún controvertido, actualmente existe bibliografía que reporta buenos resultados del tratamiento con lavado endoscópicos asociado al tratamiento combinado endovenoso e intraventricular para lograr mayores concentraciones de antibiótico intraventricular. Conclusión: Consideramos que el tratamiento combinado es una herramienta frente a las ventriculitis por patógenos resistentes a los tratamientos convencionales. En los casos con obstrucción del acueducto de Silvio recomendamos realizar acueductoplastia y colocación de catéter multifenestrado; para mantener la permeabilidad y la llegada de antibiótico al cuarto ventrículo.

Introduction: Ventriculitis represents an infectious emergency which is normally associated with neurosurgical procedures. The incidence is unknown due to the variation of the diagnostic criteria. Case description: We present a 6-month-old female patient with a history of post-hemorrhagic hydrocephalus. The patient was diagnosed with Enterobacter complex ventriculitis difficult to manage associated with peritoneal ventricular shunt (VP). The patient received combined antibiotic treatment with Meropenem intravenous and intravenous-intraventricular Colistin associated with endoscopic treatment. This endoscopic treatment consisted of washes, aspiration of the intraventricular purulent content, third endoscopic ventriculostomy (ETV), bilateral coagulation of the choroid plexus and aqueductoplasty with external ventricular drain catheter (EDV). This EDV was placed between the third and fourth ventricle in order to maintain its permeability so as to ensure the arrival of intraventricular antibiotics to the fourth ventricle. Discussion: Ventriculitis is associated with multiple complications and a high morbidity and mortality rate. The treatment of ventriculitis that is difficult to manage is still controversial. Currently several authors show good results of endoscopic lavage treatment associated with combined intravenous/intraventricular antibiotic treatment. This leads to greater intraventricular antibiotic concentrations. Conclusion: We consider that combined treatment has been successful for ventriculitis difficult to manage. In those cases, with obstruction of the Silvio aqueduct, it is recommended to perform aqueductoplasty and placement of a multi-fenestrated catheter; to maintain patency and the arrival of antibiotics in the fourth ventricle.

Continuous Positive Airway Pressure vs. High Flow Nasal Cannula in children with acute severe or moderate bronchiolitis. A systematic review and Meta-analysis.

OBJECTIVE: To compare the safety and effectiveness of Continuous Positive Airway Pressure (CPAP) vs. High Flow Nasal Cannula (HFNC) to prevent therapeutic failure and the need of invasive ventilation in children with acute moderate-severe bronchiolitis. DESIGN: A systematic review and meta-analysis. SETTING: Medline, Embase, Lilacs, Cochrane and gray literature (May 2020) was performed. PARTICIPANTS: Randomized clinical trials patients with moderate to severe bronchiolitis. MAIN VARIABLES: Therapeutic failure, need for invasive ventilation, adverse events, length of PCCU and of hospital stay. INTERVENTION: The quality of the studies was assessed with the Cochrane risk and bias tool. We conducted meta-analysis using fixed effect model and random effects model. RESULTS: Three RCTs were included. Showed less risk of therapeutic failure with CPAP compared with HFNC (RR=0.7; 95%CI 0.5-0.99) developed hours later in patients with CPAP (MD=3.16; 95%CI 1.55-4.77). We did not find differences in other outcomes, such as need of invasive ventilation (RR=0.60; 95%CI 0.25-1.43), apnea (RR=0.40; 95%CI 0.08-1.99), or number of days in the intensive care unit (MD=0.02; 95%CI -0.38 to 0.42), and length of hospitalization (MD=-1.00; 95%IC -2.66 to 0.66). Adverse events (skin lesions) were more common with CPAP (RR 2.47; 95%CI 1.17-5.22). CONCLUSIONS: In moderate/severe bronchiolitis CPAP demonstrated a lower risk of therapeutic failure and a longer time to failure. But more adverse events like nasal injury. There were no differences in other variables.

Changes in motor function and brain cortex mitochondrial active oxygen species production in aged mice.

Neuronal ageing is a complex physiological process, associated to metabolic and motor changes. In this study, 3 and 17 months old male Swiss mice were used. Aged mice exhibited a significant reduction in motor performance and walking footprint pattern. Synaptosomes and mitochondrial fractions were isolated from mouse brain cortex. Active oxygen species and cardiolipin content were measured in both subcellular fractions. Synaptosomal acetylcholinesterase activity was measured in both animal age groups. Results showed that superoxide levels were 42.9% lower in synaptosomes from old mice as compared with young animals, while no changes were observed in non-synaptic mitochondria. Succinate-glutamate dependent H2O2 production rate was 27.5% decreased in non-synaptic mitochondria from aged mice. Cardiolipin content was 21% decreased in synaptosomes from 17-months old animals, while no changes were observed in non-synaptic mitochondria. Acetylcholinesterase activity decreased 16% in 17-months old mice, as compared with young animals. Age-related alterations in neuronal function could be associated with changes in active oxygen species at synapses, with parallel motor deficiencies.

Potential Applications of Silk Fibroin as Vascular Implants: A Review.

Cardiovascular disease is a worldwide main cause of morbidity and mortality. Treatment alternatives include the use of cardiovascular implants that have generated a constant search for materials, and transformation processes that provide structures similar to those that need to be replaced. Among the biomaterials available for vascular implants, silk fibroin (SF) is of great interest because it is a natural, biodegradable, biocompatible protein. In addition, SF has outstanding mechanical properties and can be easily processed by various techniques. This article presents a general review of SF, its potential use as a biomaterial for vascular applications, and modifications that improve its hemocompatibility.

An apparatus based on an atomic force microscope for implementing tip-controlled local breakdown.

Solid-state nanopores are powerful tools for sensing of single biomolecules in solution. Fabrication of solid-state nanopores is still challenging, however; in particular, new methods are needed to facilitate the integration of pores with larger nanofluidic and electronic device architectures. We have developed the tip-controlled local breakdown (TCLB) approach, in which an atomic force microscope (AFM) tip is brought into contact with a silicon nitride membrane that is placed onto an electrolyte reservoir. The application of a voltage bias at the AFM tip induces a dielectric breakdown that leads to the formation of a nanopore at the tip position. In this work, we report on the details of the apparatus used to fabricate nanopores using the TCLB method, and we demonstrate the formation of nanopores with smaller, more controlled diameters using a current limiting circuit that zeroes the voltage upon pore formation. Additionally, we demonstrate the capability of TCLB to fabricate pores aligned to embedded topographical features on the membranes.

Ablación cardiaca auricular: estrategias guiadas por el mapeo de electrogramas / Catheter Ablation for Atrial Fibrillation: Electrogram-Guided Methods

Resumen La ablación por radiofrecuencia se ha constituido como la técnica más utilizada para el tratamiento intervencionista de la fibrilación auricular. El aislamiento eléctrico de venas pulmonares se ha convertido en el procedimiento convencional, principalmente en pacientes con fibrilación auricular paroxística. Sin embargo, la tasa de éxito mediante esta técnica en pacientes con fibrilación auricular persistente es alrededor del 50%. Aunque se han propuesto diversas estrategias para guiar al electrofisiólogo en los procedimientos de ablación, estudios recientes muestran que la generación de líneas de ablación adicionales guiadas anatómicamente o mediante mapeo de electrogramas complejos fragmentados, no mejora la tasa de éxito del procedimiento convencional de aislamiento de venas pulmonares. En esta revisión, se consideran las limitaciones que representan los métodos de mapeo electrofisiológicos actuales, las nuevas estrategias de evaluación de los electrogramas y los métodos de procesamiento de señales que se ven propuestos en el futuro más inmediato, para guiar los procedimientos de ablación particularmente en pacientes con fibrilación auricular persistente.

Abstract Radiofrequency catheter ablation has evolved into an effective treatment option for drug-resistant patients with atrial fibrillation. Electrical isolation of the pulmonary veins has become the standard ablation strategy mainly in patients with paroxysmal atrial fibrillation. However, the success rate of pulmonary veins isolation is about 50% in patients with persistent atrial fibrillation. Although different strategies to guide the electrophysiologist in ablation procedures have been proposed. Recent studies show that the generation of additional ablation lines guided anatomically or by fragmented complex electrograms mapping does not improve the success rate of the conventional pulmonary veins isolation procedure. In this review, we describe the limitations of current electrophysiological mapping methods, the new electrogram evaluation strategies and the signal processing methods that are proposed in the immediate future, to guide ablation procedures, particularly in patients with atrial fibrillation persistent.