After the World Health Organization declared the COVID-19 outbreak a pandemic, the number of patients with confirmed SARS-CoV-2 infection (COVID-19) has increased exponentially, and ...gastroenterologists and other specialists most likely will be involved in the care of those patients.
To evaluate the knowledge Latin American gastroenterologists and endoscopists (staff physicians and residents) have about the characteristics of COVID-19, as well as the prevention measures to be taken during endoscopic procedures.
We conducted a cross-sectional study that included gastroenterologists and endoscopists from 9 Latin American countries. An electronic questionnaire was applied that was designed to evaluate the knowledge of symptoms, risk groups for severe disease, prevention measures, and the reprocessing of endoscopes utilized in patients with COVID-19.
Information was obtained from 133 physicians. Ninety-five percent of them correctly identified the most frequent symptoms of the virus, and 60% identified the 3 risk groups for severe disease. Sixty-six percent of those surveyed did not consider it necessary to use standard precautions during endoscopic procedures, and 30% did not consider contact precautions necessary. Forty-eight percent of the participants surveyed were not familiar with the protocol for reprocessing the endoscopes utilized in patients with COVID-19.
The majority of the gastroenterologists and endoscopists surveyed were familiar with the signs and symptoms of COVID-19 and the populations at risk for complications. There was a lack of knowledge about prevention measures (during clinical care and endoscopic procedures) and the reprocessing of endoscopic equipment by 70% and 48%, respectively, of those surveyed. Dissemination and teaching strategies that increase the knowledge of specific biosafety measures must be carried out.
Después de que la Organización Mundial de la Salud (OMS) declaró a la enfermedad por SARS-CoV-2 (COVID-19) pandemia, el número de pacientes con infección confirmada ha incrementado exponencialmente. Es muy probable que gastroenterólogos y otros especialistas se involucren en la atención de estos pacientes.
Evaluar el conocimiento de gastroenterólogos y endoscopistas (adscritos y residentes) en Latinoamérica sobre las características de COVID-19 y las medidas de prevención durante procedimientos endoscópicos.
Realizamos un estudio transversal que incluyó a gastroenterólogos y endoscopistas de nueve países de Latinoamérica. Se aplicó un cuestionario electrónico diseñado para valorar conocimientos sobre síntomas, grupos de riesgo para enfermedad grave, medidas de prevención y reprocesamiento de endoscopios utilizados en pacientes con COVID-19.
Se obtuvo información de 133 médicos, 95% de los encuestados identificó correctamente los síntomas más frecuentes y 60% identificó los tres grupos de riesgo para enfermedad grave. El 66% no consideró necesario usar precauciones estándar durante procedimientos endoscópicos y 30% no consideró necesarias las precauciones de contacto. El 48% desconoció el protocolo para reprocesamiento de los endoscopios en pacientes con COVID-19.
Los signos y síntomas de COVID-19 y las poblaciones de riesgo de complicaciones son conocidos por la mayoría de los gastroenterólogos y endoscopistas. El conocimiento sobre medidas de prevención (durante atención clínica y procedimientos endoscópicos), así como el reprocesamiento del equipo endoscópico son desconocidos por 70 y 48% de los encuestados respectivamente. Se deben realizar estrategias de difusión y enseñanza que incrementen el conocimiento sobre estos aspectos de bioseguridad.
•Direct screening of differences in the resistance against breakdown of the passive layers formed on steels by microelectrochemical methods.•Imaging domains of similar topography but different ...corrosion characteristics.•Distinguishing iron soluble species released from propagating pits.•Distinct effect of polarization on the onset of pit nucleation for different stainless steel compositions.
Passive film breakdown and pit nucleation on 304 and 316 stainless steels in chloride-containing media were investigated using scanning microelectrochemical microscopy (SECM) and the scanning vibrating electrode technique (SVET). Experiments were performed for the alloys either at their corresponding open circuit potential, or under applied polarization, as to image domains of similar topography but different resistance against breakdown of the passive layers formed on these steels. Identification of the iron released species was accomplished, showing that pitting occurs with the formation of iron (II) species only. Detection of iron (III) species occurred when the steel sample was polarized at high positive overpotentials because it served as the reaction site to oxidize the iron (II) ions released from a propagating pit. The obtained results have revealed some difference of the reactivity of both specimens. Moreover the effect of the galvanic coupling has been investigated.
Safflower (Carthamus tinctorius L.) possesses the highest amount of linoleic acid among the 10 major vegetable oil crops of the world. Very high linoleic acid content is controlled by recessive ...alleles at a single locus Li. However, deviated segregations from the expected monogenic inheritance have been observed in crosses involving nuclear male-sterile (NMS) lines. The present research was undertaken to study the inheritance of very high linoleic acid content in safflower and its relationship with nuclear male sterility. F₁, F₂, F₃, BC₁F₁ and BC₁F₂ seed generations were evaluated in a cross between CR-142 (a line with very high linoleic acid content, 88%) and CL1 (an NMS line with wild-type linoleic acid content, 74%). The genetics of linoleic acid content in male-sterile plants was determined by testcrossing with CR-142. The results confirmed monogenic inheritance. The analysis of the F₃ and BC₁F₂ to CL1 seed generations demonstrated a repulsion-phase linkage between Li and Ms loci, the latter conferring the NMS trait. The recombination rate between Li and Ms was estimated to be 0.09.
The mechanisms of the complex cascade cyclizations of homoallenyl aldazines and analogues to afford tetracyclic compounds has been computed. Double sequential crisscross 1,3‐dipolar cycloaddition ...through azomethine imine intermediates was characterized both for the homoallenyl aldazine and for its ketene analogue. If conjugation of the two interacting groups (azine and allene/ketene) was introduced through the presence of an olefin system or an oxygen atom in place of the saturated carbon, pseudopericyclic mechanisms were also characterized. Unlike in the parent system, the barrierless cascade electrocyclization of (Z)‐hexa‐2,4,5‐trien‐1‐ylidenehydrazine and of its ketene analogue is interrupted after formation of the 2,2′‐methylenebis(dihydropyridine) and bis‐2,2′‐pyridone, respectively, by pseudoelectrocyclic reactions. The cascade reaction of a hypothetical diazine with an allenylformimidate structure generates a compound containing four fused five‐membered heterocyclic rings through a sequence that differs from that of the parent homoallenyl aldazine in the involvement of 6π‐electron‐5‐atom electrocyclization and nucleophile–electrophile reaction steps before the final 1,3‐dipolar cycloaddition. The analysis of the aromaticities of the transition structures through the computation of the NICS is consistent with their characterization as pericyclic or pseudopericyclic processes.
Concerted but consecutive pericyclic and pseudopericyclic reactions have been characterized by DFT computations for crisscross 1,3‐cycloaddition and electrocyclization reaction cascades of aldazines to provide complex tetracyclic derivatives containing up to four heteroatoms.
Background
The interest in non-manipulated cells originating from adipose tissue has raised tremendously in the field of tissue engineering and regenerative medicine. The resulting stromal vascular ...fraction (SVF) cells have been successfully used in numerous clinical applications. The aim of this experimental work is, first to combine a macroporous synthetic mesh with SVF isolated using a mechanical disruption process, and to assess the effect of those cells on the early healing phase of hernia.
Methods
Human SVF cells combined with fibrin were used to coat commercial titanized polypropylene meshes. In vitro, viability and growth of the SVF cells were assessed using live/dead staining and scanning electron microscopy. The influence of SVF cells on abdominal wall hernia healing was conducted on immunodeficient rats, with a focus on short-term vascularization and fibrogenesis.
Results
Macroporous meshes were easily coated with SVF using a fibrin gel as temporary carrier. The in vitro experiments showed that the whole process including the isolation of human SVF cells and their coating on PP meshes did not impact on the SVF cells’ viability and on their capacity to attach and to proliferate. In vivo, the SVF cells were well tolerated by the animals, and coating mesh with SVF resulted in a decrease degree of vascularity compared to control group at day 21.
Conclusions
The utilization of SVF-coated mesh influences the level of angiogenesis during the early onset of tissue healing. Further long-term animal experiments are needed to confirm that this effect correlates with a more robust mesh integration compared to non-SVF-coated mesh.
La enfermedad por coronavirus 2019 (COVID-19) es causada por el virus del síndrome respiratorio agudo grave-coronavirus2 (SARS-CoV-2). La COVID-19 ha afectado a unos 6millones de personas en todo el ...mundo en menos de 4meses posterior al reporte de los primeros casos en China en diciembre de 2019. La relación que guarda la enfermedad por SARS-CoV-2 con el tratamiento inmunosupresor utilizado en diversos trastornos gastrointestinales es incierta, y esto genera el debate sobre suspender el tratamiento inmunosupresor para mejorar el pronóstico de la infección, lo cual incluye el riesgo inherente de rechazo de injerto o agudización de enfermedades autoinmunes que potencialmente pudieran agravar el curso de la infección. En base a la evidencia disponible se logra establecer una postura de tratamiento en pacientes con enfermedades gastrointestinales que requieren terapia inmunosupresora.
The coronavirus disease 2019 (COVID-19) is caused by the severe acute respiratory syndrome coronavirus2 (SARS-CoV-2) virus. COVID-19 affected more than 6million persons worldwide in fewer than 4 months, after the report of the first cases in China in December 2019. The relation of the disease caused by SARS-Cov-2 to immunosuppressive treatment used in different gastrointestinal disorders is uncertain, resulting in debate with regard to suspending immunosuppressive therapy to improve infection outcome. Said suspension implies the inherent risk for graft rejection or autoimmune disease exacerbation that can potentially worsen the course of the infection. Based on the presently available evidence, a treatment stance has been established for patients with gastrointestinal diseases that require immunosuppressive therapy.
Introducción: Los invernaderos se clasifican por niveles alto, medio o bajo según las tecnologías que se le adapten, con la que se crean condiciones óptimas de radiación, temperatura, humedad y ...dióxido de carbono que permiten mejorar la producción agrícola, así como el desarrollo de organismos perjudiciales que se combaten aplicando plaguicidas, exponiendo a los jornaleros a sus vapores y residuos.Método: Se determinó el daño genotóxico en muestras de células epiteliales de exfoliación bucal de los jornaleros a través del ensayo de micronúcleos, de 40 jornaleros expuestos a plaguicidas, 20 laboraron en invernaderos de baja tecnología y 20 en invernaderis de tecnología alta.Resultados: Los de baja tecnología mostraron resultados más altos de frecuencias para todas las anormalidades nucleares comparando con el grupo control, especialmente de cromatina condensada, picnosis, cariolisis y micronúcleos. Al calcular el riesgo, se midió las frecuencias de micronúcleos en razón de probabilidades (OR), para los jornaleros de invernaderos de alta tecnología el OR = 17.06 (95 % IC 3.4-83.7) y de baja tecnología OR = 50.66 (% IC 7.5-341.7).Conclusión: Los resultados indican que los jornaleros que laboran en invernaderos de baja tecnología muestran una mayor frecuencia de células con anormalidades nucleares, debido al efecto de condiciones laborales y exposición a los plaguicidas.
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•Microelectrochemical characterization of the effect of polarization on the localized corrosion of 304 stainless steel.•Spatially-resolved detection of local release of Fe(II) ions, ...and their conversion to Fe(III), as function of polarization.•Susceptibility to localized corrosion influenced by surface modification of the surface.•Onset of anodic local dissolution monitored by SVET as function of acidity and chloride ion concentration.
Corrosion processes occurring on stainless steel 304 surfaces under anodic polarization were characterized using scanning electrochemical microscopy (SECM) and the scanning vibrating electrode technique (SVET), complemented with conventional potentiodynamic polarization curves. Stable pit formation on the samples was monitored by SVET as result of surface modification under electrochemical control. The operation procedure may involve the previous electrochemical reduction of the passive oxide layer if the media is not aggressive enough to induce pitting at small overpotentials. Additionally, the sample generation – tip collection operation mode of the SECM enabled to detect local release of iron (II) ions, as well as their conversion to iron (III), both processes being greatly affected by the potential applied to the substrate.
•We evaluated carrot anthocyanins as food colorants and antioxidant agents.•Physicochemical stability analyzed in carrot, grape (GRP), and synthetic (E131) colorants.•Carrot colorants had higher ...thermal stability than GRP and E131.•Carrot anthocyanins were more stable at low pH and temperature conditions.•Acylated anthocyanins were more stable than non-acylated anthocyanins.
As a means to evaluate the potential of carrot anthocyanins as food colorants and nutraceutical agents, we investigated the physicochemical stability and antioxidant capacity of purple carrot extracts under different pH (2.5–7.0) and temperature (4–40 °C) conditions, in comparison to a commercial synthetic (E131) and a natural grape-based (GRP) colorant. During incubation, the colorants were weekly-monitored for various color parameters, concentration of anthocyanins and phenolics, and antioxidant capacity. Carrot colorants were more stable than GRP; and their thermal stability was equal (at 4 °C) or higher than that of E131 (at 25–40 °C). Carrot anthocyanins had lower degradation rate at low pH and temperature, with acylated anthocyanins (AA) being significantly more stable than non-acylated anthocyanins (NAA). Anthocyanins acylated with feruloyl and coumaroyl glycosides were the most stable carrot pigments. The higher stability of carrot colorants is likely due to their richness in AA and -to a lesser extent- copigmentation with other phenolics.
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