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1.
Rev. chil. neuro-psiquiatr ; Rev. chil. neuro-psiquiatr;62(1)2024.
Article de Espagnol | LILACS-Express | LILACS | ID: biblio-1559693

RÉSUMÉ

Introducción: La detección temprana del deterioro cognitivo en personas mayores permite disminuir la incertidumbre y mejorar las tareas de intervención. El objetivo de esta investigación fue determinar las características psicométricas de un protocolo de cribado online para detectar tempranamente deterioro leve en personas mayores. Método: el método usado fue de tipo mixta con preguntas de tipo cuantitativas y cualitativas. La muestra fue de 75 personas mayores del gran Concepción, región del Bio-Bio. El protocolo estaba compuesto por: Cuestionario sociodemográfico, Test del Reloj Versión Cacho, Moca, Escala Depresión Yesavage y Test Acentuación de Palabras. El procedimiento consistió en la aplicación del protocolo a través de un Tablet o Laptop, videollamadas. Resultados: Se encontró que el protocolo presenta validez discriminante y convergente. Conclusiones: se concluye que el protocolo de cribado online para detectar tempranamente deterioro leve en personas mayores es válido y fiable. Se discute el uso y la aplicación de un protocolo cribado usando la Teleneuropsicología (TeleNP), en personas mayores


ABTRACT Introduction: Early detection of cognitive impairment in the elderly allows us to reduce uncertainty and improve intervention tasks. The objective of this research was to determine the psychometric characteristics of an online screening protocol for early detection of mild impairment in the elderly. Method: the method used was of a mixed type with quantitative and qualitative questions. The sample consisted of 75 older people from the greater Concepción, Bio-Bio region. The protocol consisted of: Sociodemographic Questionnaire, Cacho Version Clock Test, Mocha, Yesavage Depression Scale and Word Stress Test. The procedure consisted of the application of the protocol through a Tablet or Laptop, video calls. Results: It was found that the protocol presents discriminant and convergent validity. Conclusions: it is concluded that the online screening protocol for early detection of mild deterioration in the elderly is valid and reliable. The use and application of a screening protocol using Teleneuropsychology (TeleNP) in older people is discussed.

2.
Immunol Lett ; 264: 4-16, 2023 Dec.
Article de Anglais | MEDLINE | ID: mdl-37875239

RÉSUMÉ

The thymus is the anatomical site where T cells undergo a complex process of differentiation, proliferation, selection, and elimination of autorreactive cells which involves molecular signals in different intrathymic environment. However, the immunological functions of the thymus can be compromised upon exposure to different infections, affecting thymocyte populations. In this work, we investigated the impact of malaria parasites on the thymus by using C57BL/6 mice infected with Plasmodium berghei ANKA and Plasmodium yoelii 17XL; these lethal infection models represent the most severe complications, cerebral malaria, and anemia respectively. Data showed a reduction in the thymic weight and cellularity involving different T cell maturation stages, mainly CD4-CD8- and CD4+CD8+ thymocytes, as well as an increased presence of apoptotic cells, leading to significant thymic cortex reduction. Thymus atrophy showed no association with elevated serum cytokines levels, although increased glucocorticoid levels did. The severity of thymic damage in both models reached the same extend although it occurs at different stages of infection, showing that thymic atrophy does not depend on parasitemia level but on the specific host-parasite interaction.


Sujet(s)
Paludisme , Plasmodium yoelii , Animaux , Souris , Plasmodium berghei , Souris de lignée C57BL , Atrophie , Parasitémie
3.
Nanotechnology ; 35(1)2023 Oct 16.
Article de Anglais | MEDLINE | ID: mdl-37751721

RÉSUMÉ

Recalcitrant pollutants present in wastewater, without an effective treatment, have several effects on aquatic ecosystems and human health due to their chemical structure and persistence. Therefore, it is crucial the development of efficient technologies to eliminate such pollutants in water. Nano-photocatalysts are considered a promising technology for water remediation; however, one common drawback is the difficulty of recovering it after water processing. One effective strategy to overcome such problem is its immobilization into substrates such as polymeric membranes. In this study, a polymeric membrane with embedded Mg0.975Ni0.025SiO3is proposed to remove model pollutants diclofenac sodium and methylene blue dye by synergetic adsorption and photocatalytic processes. Mg0.975Ni0.025SiO3was synthesized by the combustion method. The matrix polymeric blend consisting of a blend of cellulose acetate, crystalline nanocellulose and polyvinylidene fluoride was obtained by the phase inversion method. The composite membranes were characterized by FTIR, x-ray diffraction, and scanning electron microscopy. With pollutant solutions at pH 7, the pollutant adsorption capacity of the membranes reached up to 30% and 45% removal efficiencies for diclofenac sodium and methylene blue, respectively. Under simulated solar irradiation photocatalytic removal performances of 70% for diclofenac sodium pH 7, and of 97% for methylene blue dye at pH 13, were reached. The membrane photocatalytic activity allows the membrane to avoid pollutant accumulation on its surface, given a self-cleaning property that allows the reuse of at least three cycles under sunlight simulator irradiation. These results suggest the high potential of photocatalytic membranes using suitable and economical materials such as cellulosic compounds and magnesium silicates for water remediation.

4.
J. health med. sci. (Print) ; 9(3): 37-49, jul.2023. graf, tab
Article de Espagnol | LILACS | ID: biblio-1523961

RÉSUMÉ

RESUMEN Los Niveles de Referencia para Diagnóstico (NRD) son una herramienta dinámica que gana cada vez una mayor importancia para la optimización de las exposiciones médicas. La disponibilidad de información científica es esencial en este proceso de optimización para Medicina Nuclear (MN) y Radiología Diagnóstica (RD). Este trabajo presenta un estudio de la disponibilidad de información sobre los NRD para MN y RD en la base PubMed, en los últimos 20 años, empleando diferentes palabras clave. Se analizó de forma crítica la información disponible, buscando los cambios principales que se han producido como tendencia en diferentes aspectos del establecimiento de los NRD. Se verificó un desbalance significativo en la disponibilidad de literatura científica en estas dos áreas, aunque se ha incrementado la información para equipos híbridos y de forma general para todas las tecnologías. Este desbalance se hace mayor para estudios de medicina nuclear en pediatría. Se observaron avances en la forma de recolectar datos, la manera de organizar la información y analizarla, en especial con la disponibilidad de sistemas de monitoreo de dosis. Se encontró que, en los estudios TC e intervencionismo, las agrupaciones por localización anatómica están siendo acotadas o restringidas, por indicaciones clínicas que tienen similitudes en los requisitos de calidad de imagen para el diagnóstico adecuado. Similarmente en MN se vislumbra la incorporación de la actividad por peso como NRD en las tecnologías híbridas y estudios pediátricos. Este estudio demuestra que, en general, la literatura científica disponible sobre los NRD es mucho más amplia para pacientes adultos. Se requiere más estudios pediátricos, especialmente en el área de MN


ABSTRACT Diagnostic Reference Levels (DRLs) are a dynamic tool that is gaining more and more importance for the optimization of medical exposures. The availability of scientific information is essential in this optimization process for Nuclear Medicine (NM) and Diagnostic Radiology (DR). This work presents a revision of the information's availability about DRL in the PubMed database, in the last 20 years, using different search combinations. The available information was critically analyzed, looking for the main changes that have occurred as a trend in different aspects of the establishment of the NRD. A significant disparity in the amount of information between the two areas on the subject was verified, although there has been an increase of available scientific papers for hybrid equipment, and in general for all technologies. The disparity becomes greater for NM studies in pediatrics population. The way to collect data, the mode to organize the information and analyze it, has also undergone changes, mainly with radiation dose management systems. In CT and interventional studies, the grouping by anatomical locations is being constrained or modulated by clinical indications with analogous image quality requirements for proper diagnosis. Something similar happens in MN, where the incorporation of activity/patient's weight is envisioned as NRD for hybrid technologies and pediatric studies. In general, the study showed that, the scientific paper's availability about DRL for adult population are much wider. More pediatric studies on these subjects are needed, especially in NM


Sujet(s)
Humains , Dose de rayonnement , Niveaux de référence diagnostiques , Médecine nucléaire
5.
Food Res Int ; 170: 113010, 2023 08.
Article de Anglais | MEDLINE | ID: mdl-37316077

RÉSUMÉ

Dysphagia is a condition that affects the ability to chew and swallow food and beverages, having a major impact on people's health and wellbeing. This work developed gel systems with a customized texture suitable for intake by dysphagic people using 3D printing and milk. Gels were developed using skim powdered milk, cassava starch (native and modified by the Dry Heating Treatment (DHT)), and different concentrations of kappa-carrageenan (ĸC). The gels were evaluated in relation to the starch modification process and concentration of gelling agents, 3D printing performance, and suitability for dysphagic people (following both the standard fork test described by the International Dysphagia Diet Standardization Initiative (IDDSI), and also using a new device coupled to a texture analyzer). Moreover, the best formulations were evaluated for mineral bioaccessibility through simulated gastrointestinal digestion based on INFOGEST 2.0 standardized method. The results showed that ĸC had a dominant effect compared to the DHT-modified starch on gel texture, 3D printing performance, and fork tests. The gels obtained by molding or 3D printing resulted in different behaviors during the fork test, which was associated with the gel extrusion process that breaks down their initial structure. The strategies applied to tailor the texture of the milk did not affect the mineral bioaccessibility, which was kept high (>80%).


Sujet(s)
Troubles de la déglutition , Lait , Humains , Animaux , Amidon , Carragénane , Gels , Minéraux , Impression tridimensionnelle
6.
Heliyon ; 9(6): e16439, 2023 Jun.
Article de Anglais | MEDLINE | ID: mdl-37251478

RÉSUMÉ

Introduction: The COVID-19 pandemic led to the transition to remote work, triggering variations in stress and physical activity (PA), associated with context-specific instability. Objective: To identify the association between perceived stress (PS) and the level of physical activity (PA) and explore its relationship with the sociodemographic, family, work and individual characteristics of professors working remotely during the COVID-19 pandemic. Material and methods: Cross-sectional analytical study based on a virtual survey of professors. PS was assessed using the Perceived Stress Scale (PSS-14), and PA using an International Physical Activity Questionnaire. The prevalence of high PS and the association with PA were estimated using a Poisson regression analysis with robust variance that estimated crude prevalence ratios (cPR) and adjusted prevalence ratios (aPR) with a 95% confidence interval (CI). Five models were developed to assess associations of PS and PA with sociodemographic, family, work, and individual variables. Results: The information of 191 professors was analyzed; 39.27% were women, aged 52 (41-60). The prevalence of high stress was 47.12%. The age and being head of household did not show significant individual associations with PS. However, the regression analysis assessing the association of PS and other factors showed that compared to the moderate PA group, a statistically significant association was found between stress and high PA (aPR = 0.19; 0.06-0.59), low PA (aPR = 1.43; 1.02-2.01), mainly influenced by age, being head of household and sleep quality. Conclusion: Stress was associated with PA level, family and individual factors. These findings allow identifying characteristics, such as being head of household, age and quality of sleep among teachers, as being associated with a higher probability of having high stress. Subsequent studies should consider the role of individuals and working conditions as part of occupational health surveillance, given the presence of hybrid education in the education sector.

7.
Rev. ANACEM (Impresa) ; 17(1): 31-36, 2023. ilus
Article de Espagnol | LILACS | ID: biblio-1525890

RÉSUMÉ

El Eritema multiforme (EM) o eritema polimorfo es una enfermedad aguda de la piel de naturaleza inmunológica con o sin compromiso de mucosas, que puede comportarse como crónica recurrente. Se presenta con lesiones cutáneas en diana distintivas, a menudo acompañado de úlceras o bullas en mucosas (oral, genital u ocular). Entre sus formas clínicas se distingue: una forma menor caracterizado por un síndrome cutáneo leve y su forma mayor que se manifiesta como una afectación cutánea con daño mucoso marcado. Entre sus principales diagnósticos diferenciales se encuentran el Síndrome de Stevens-Johnson (SSJ) y Síndrome de Lyell (Necrólisis epidérmica tóxica (NET)). Tiene una incidencia estimada < 1%, siendo su forma mayor levemente más frecuente que su forma menor (0.8-6 por millón/año). Puede darse a cualquier edad, presentando un peak de incidencia entre los 20 y 30 años, predominando ligeramente el sexo masculino con una proporción 3:2, sin predilección racial. Su presentación en edad pediátrica es rara, más aún en la primera infancia. En esta población es más frecuente el EM menor recurrente. En el presente texto se reporta un caso de EM en población pediátrica como una rara forma de presentación exantemática, abordado en el Servicio de Pediatría del Complejo Asistencial Dr Victor Rios Ruiz (CAVRR)en la ciudad de Los Ángeles, Chile en el presente año.


Erythema multiforme (EM) also known as polymorph erythema is an acute skin disease of immunological nature with or without mucous membrane involvement, which may behave as chronic recurrent. It presents with distinctive targets like skin lesions, often together with ulcers or bullae in mucous membranes (oral, genital or ocular). Among its clinical forms are: a minor form characterized by a mild skin syndrome and its major form that manifests as a skin disease with marked mucosal damage. Among its main differential diagnoses are Stevens-Johnson Syndrome (SJS) and Lyell Syndrome (Toxic Epidermal Necrolysis (TEC)). It has an estimated incidence < 1%, with its major form being slightly more frequent than its minor form (0. 8-6 per million/year). It can occur at any age, presenting a peak incidence at the age between 20 and 30 years, with a slight predominance of males with a 3:2 ratio, without racial predilection. Its presentation in pediatric age is rare, even more so in early childhood. Minor recurrent EM is more common in this population. This paper reports a case of EM in the pediatric population as a rare form of exanthematic presentation, addressed at the Department of Pediatrics of the Complejo Asistencial Victor Rios Ruiz (CAVRR) in the city of Los Angeles, Chile this year.


Sujet(s)
Humains , Femelle , Enfant , Érythème polymorphe/diagnostic , Érythème polymorphe/étiologie , Érythème polymorphe/thérapie , Hormones corticosurrénaliennes/usage thérapeutique , Syndrome de Stevens-Johnson , Allergie et immunologie , Exanthème/étiologie , Exanthème/ethnologie
8.
Rev Gastroenterol Mex (Engl Ed) ; 87(3): 362-379, 2022.
Article de Anglais | MEDLINE | ID: mdl-35778341

RÉSUMÉ

Hepatocellular carcinoma (HCC) is more frequently manifesting as one of the main complications of cirrhosis of the liver, its principal risk factor. There have been modifications in its incidence over the past decade, related to an epidemiologic transition in the etiology of cirrhosis, with a decrease in the prevalence of hepatitis C and an increase in nonalcoholic fatty liver disease (NAFLD) as a cause, as well as the development of HCC in the non-cirrhotic liver due to NAFLD. Genetic markers associated with the disease have been identified, and surveillance and diagnosis have improved. Regarding treatment, surgical techniques, in both resection and transplantation, have advanced and radiologic techniques, at the curative stage of the disease, have enhanced survival in those patients. And finally, there have been radical changes in the systemic approach, with much more optimistic expectations, when compared with the options available a decade ago. Therefore, the Asociación Mexicana de Hepatología decided to carry out the Second Mexican Consensus on Hepatocellular Carcinoma, which is an updated review of the available national and international evidence on the epidemiology, risk factors, surveillance, diagnosis, and treatment of the disease, to offer the Mexican physician current information on the different topics regarding hepatocellular carcinoma. In this second part of the document, the topics related to the treatment of HCC are presented.


Sujet(s)
Carcinome hépatocellulaire , Tumeurs du foie , Stéatose hépatique non alcoolique , Carcinome hépatocellulaire/diagnostic , Carcinome hépatocellulaire/épidémiologie , Carcinome hépatocellulaire/étiologie , Consensus , Humains , Cirrhose du foie/complications , Tumeurs du foie/diagnostic , Tumeurs du foie/épidémiologie , Tumeurs du foie/étiologie , Stéatose hépatique non alcoolique/épidémiologie
9.
Arq. bras. med. vet. zootec. (Online) ; 74(3): 437-445, May-June 2022. tab, graf
Article de Anglais | VETINDEX | ID: biblio-1383781

RÉSUMÉ

The objective of this study was to determine pH and the concentrations of Calcium (Ca2+), Magnesium (Mg2+), Chloride (Cl-), Sodium (Na+), Potassium (K+) and Calcium (Ca2+) in the mammary gland secretion in pre-foaling Mangalarga Marchador (MM) mares to determine the best method to predict parturition in the breed. Forty-two pregnant MM mares were evaluated once daily from 310 days of gestation until parturition. Mammary gland secretion pH, measured by pH meter and pH paper strip, Mg2+, Ca2+ and Cl- levels significantly changed during the last 10 days prior to parturition (p<0.05). The lowest pH mean value (pH meter=6.67±0.42; pH strip=6.23±0.53) and significantly higher mean concentrations of Ca2+ (12.6±5.8mmol/L) and Mg2+ (10.93±3.66mmol/L) were obtained 24 hours prior to foaling (p<0.0001). Chloride levels reduced significantly 8 days prior to parturition (p<0.0001) but remained unchanged until the due date. Mammary gland pH secretion, measured by pH meter and pH paper strip, was effective to predict parturition. Quantitative pH values obtained with the pH meter had a greater accuracy in comparison to pH paper strips, but a strong correlation was found between both methods. Calcium and magnesium were the only electrolytes that changed in concentration immediately prior to parturition and are better indicators of when not to expect foaling.


O objetivo deste estudo foi determinar o pH e as concentrações de cálcio (Ca2+), magnésio (Mg2+), cloro (Cl-), sódio (Na+) e potássio (K+) na secreção da glândula mamária de éguas Mangalarga Marchador (MM) no período pré-parto, a fim de determinar o melhor método para predizer proximidade do parto na raça. Quarenta e duas éguas MM foram avaliadas diariamente a partir dos 310 dias de gestação até o parto. O pH, aferido pelo pHmetro e por fitas reagentes, e os eletrólitos Ca2+, Mg2+ e Cl- apresentaram diferenças significativas em suas concentrações nos últimos 10 dias pré-parto (P<0,05). A diminuição significativa dos valores médios de pH (pHmetro= 6,67±0,42; fitas reagentes= 6,23±0,53) e o aumento significativo nas concentrações médias de Ca2+ (12,6±5,8mmol/L) e Mg2+ (10,93±3,66mmol/L) foram observados 24 horas pré-parto (P<0,0001). As concentrações de cloro diminuíram significativamente oito dias antes do parto (P<0,0001), porém continuaram sem alteração até o momento da parição. O pH da secreção foi eficaz para predizer o momento do parto. Valores quantitativos obtidos por meio do pHmetro apresentaram maior acurácia em comparação às fitas de pH, porém obteve-se forte correlação entre os dois métodos. Cálcio e magnésio foram os únicos eletrólitos que apresentaram alterações significativas no pré-parto imediato e são indicadores mais precisos de quando não esperar o parto.


Sujet(s)
Animaux , Sécrétions corporelles , Parturition , Électrolytes , Equus caballus
10.
Rev Gastroenterol Mex (Engl Ed) ; 87(2): 216-234, 2022.
Article de Anglais | MEDLINE | ID: mdl-35431142

RÉSUMÉ

Hepatocellular carcinoma (HCC) is more frequently manifesting as one of the main complications of cirrhosis of the liver, its principal risk factor. There have been modifications in its incidence over the past decade, related to an epidemiologic transition in the etiology of cirrhosis, with a decrease in the prevalence of hepatitis C and an increase in nonalcoholic fatty liver disease (NAFLD) as a cause, as well as the development of HCC in the non-cirrhotic liver due to NAFLD. Genetic markers associated with the disease have been identified, and surveillance and diagnosis have improved. Regarding treatment, surgical techniques, in both resection and transplantation, have advanced and radiologic techniques, at the curative stage of the disease, have enhanced survival in those patients. And finally, there have been radical changes in the systemic approach, with much more optimistic expectations, when compared with the options available a decade ago. Therefore, the Asociación Mexicana de Hepatología decided to carry out the Second Mexican Consensus on Hepatocellular Carcinoma, which is an updated review of the available national and international evidence on the epidemiology, risk factors, surveillance, diagnosis, and treatment of the disease, to offer the Mexican physician current information on the different topics regarding hepatocellular carcinoma. In this first part of the document, the topics related to epidemiology and diagnosis are presented.


Sujet(s)
Carcinome hépatocellulaire , Tumeurs du foie , Stéatose hépatique non alcoolique , Carcinome hépatocellulaire/diagnostic , Carcinome hépatocellulaire/épidémiologie , Carcinome hépatocellulaire/étiologie , Consensus , Humains , Cirrhose du foie/complications , Tumeurs du foie/diagnostic , Tumeurs du foie/épidémiologie , Tumeurs du foie/étiologie , Stéatose hépatique non alcoolique/épidémiologie
11.
Clin Appl Thromb Hemost ; 28: 10760296221088576, 2022.
Article de Anglais | MEDLINE | ID: mdl-35317658

RÉSUMÉ

The antiphospholipid syndrome (APS), a systemic autoimmune disease characterized by a hypercoagulability associated to vascular thrombosis and/or obstetric morbidity, is caused by the presence of antiphospholipid antibodies such as lupus anticoagulant, anti-ß-2-glycoprotein 1, and/or anticardiolipin antibodies. In the obstetrical APS, antiphospholipid antibodies induce the production of proinflammatory cytokines and tissue factor by placental tissues and recruited neutrophils. Moreover, antiphospholipid antibodies activate the complement system which, in turn, induces a positive feedback leading to recruitment of neutrophils as well as activation of the placenta. Activation of these cells triggers myometrial contractions and cervical ripening provoking the induction of labor. In thrombotic and obstetrical APS, antiphospholipid antibodies activate endothelial cells, platelets, and neutrophils and they may alter the multimeric pattern and concentration of von Willebrand factor, increase the concentration of thrombospondin 1, reduce the inactivation of factor XI by antithrombin, increase the activation of factor XII, and reduce the activity of tissue plasminogen activator with the subsequent production of plasmin. All these effects result in less permeable clots, denser, thinner, and with more branched fibrin fibers which are more difficult to lysate. As a consequence, thrombosis, the defining clinical criterion of APS, complicates the clinical course of the patient.


Sujet(s)
Syndrome des anticorps antiphospholipides , Activateur tissulaire du plasminogène , Syndrome des anticorps antiphospholipides/complications , Coagulation sanguine , Cellules endothéliales , Femelle , Humains , Placenta , Grossesse
13.
Int Immunopharmacol ; 97: 107674, 2021 Aug.
Article de Anglais | MEDLINE | ID: mdl-34044183

RÉSUMÉ

Cerebral malaria (CM) is a neurological complication derived from the Plasmodium falciparum infection in humans. The mechanisms involved in the disease progression are still not fully understood, but both the sequestration of infected red blood cells (iRBC) and leukocytes and an exacerbated host inflammatory immune response are significant factors. In this study, we investigated the effect of Monocyte Locomotion Inhibitory Factor (MLIF), an anti-inflammatory peptide, in a well-characterized murine model of CM. Our data showed that the administration of MLIF increased the survival and avoided the neurological signs of CM in Plasmodium berghei ANKA (PbA) infected C57BL/6 mice. MLIF administration down-regulated systemic inflammatory mediators such as IFN-γ, TNF-α, IL-6, CXCL2, and CCL2, as well as the in situ expression of TNF-α in the brain. In the same way, MLIF reduced the expression of CD31, CD36, CD54, and CD106 in the cerebral endothelium of infected animals and prevented the sequestration of iRBC and leucocytes in the brain microvasculature. Furthermore, MLIF inhibited the activation of astrocytes and microglia and preserved the integrity of the blood-brain barrier (BBB). In conclusion, our results demonstrated that the administration of MLIF increased survival and conferred neuroprotection by decreasing neuroinflammation in murine CM.


Sujet(s)
Anti-inflammatoires/administration et posologie , Paludisme cérébral/prévention et contrôle , Neuroprotecteurs/administration et posologie , Oligopeptides/administration et posologie , Animaux , Astrocytes/effets des médicaments et des substances chimiques , Astrocytes/immunologie , Encéphale/effets des médicaments et des substances chimiques , Encéphale/immunologie , Encéphale/anatomopathologie , Modèles animaux de maladie humaine , Régulation négative/effets des médicaments et des substances chimiques , Régulation négative/immunologie , Femelle , Humains , Médiateurs de l'inflammation/antagonistes et inhibiteurs , Médiateurs de l'inflammation/métabolisme , Paludisme cérébral/immunologie , Paludisme cérébral/parasitologie , Paludisme cérébral/anatomopathologie , Souris , Microglie/effets des médicaments et des substances chimiques , Microglie/immunologie , Plasmodium berghei/immunologie
14.
J Environ Manage ; 290: 112665, 2021 Jul 15.
Article de Anglais | MEDLINE | ID: mdl-33892238

RÉSUMÉ

This work presents the morphological, structural and photocatalytic properties of flexible graphene composites decorated with Ni@TiO2:W nanoparticles (TiNiW NPs) with an average size of 27 ± 2 nm. The TiNiW NPs were immobilized on the surface of a flexible graphene composite using a PVA-based slurry-paste (FG/TiNiW composite). The SEM study showed that the TiNiW NPs remained exposed on the surface of the FG/TiNiW composite, which benefited its photocatalytic activity. The photocatalytic performance for the degradation of acetaminophen (ACT) was evaluated using both the TiNiW powders and the FG/TiNiW composite, obtaining maximum degradation efficiencies of 100 and 86%, respectively, after 3 h under natural solar irradiation. The degradation of ACT was caused mainly by the reactive oxygen species such as OH radicals and h+, which was confirmed by scavenger experiments. Photoluminescence, XPS and absorbance experiments revealed that oxygen vacancy defects were created by i) doping the TiNiW NPs with W and by ii) introducing graphene into the composites. These defects enhanced the absorbance of light in the range of 400-800 nm, which in turn, promoted the photocatalytic degradation of ACT. Moreover, the reuse experiments confirmed that both the TiNiW NPs and FG/TiNiW composite were very stable for the degradation of ACT, since degradation efficiencies >82% were obtained after 4 reuse cycles for both photocatalysts. The experimental findings of this work demonstrate that the flexible TiO2/graphene composites are a feasible option for the removal of pharmaceutical contaminants from water using natural solar irradiation.


Sujet(s)
Graphite , Nanoparticules , Acétaminophène , Animaux , Catalyse , Titane , Eau
15.
Animal ; 15(2): 100132, 2021 Feb.
Article de Anglais | MEDLINE | ID: mdl-33712218

RÉSUMÉ

Information on weaning techniques in the tropics is scarce, particularly regarding the long-term effect of temporary early cow-calf separation or restricted suckling. Therefore, we studied the effects of these two handling practices on well-being and performance at 150 days postpartum in fifteen zebu cow-calf pairs randomly assigned to three treatments. Continuous suckling (CS) where calves remained with their dams from birth to weaning; restricted suckling (RS) calves were allowed to suckle 30 min/day from Day 34 until weaning at Day 150 and kept separated the rest of the time; temporary separation (TS) calves were separated for 72 h from their dams from Day 33 to 36 but remained with their dams the rest of the time. Blood samples and behavioral data were collected on Days 32-36 (1st period) and 149-153 (2nd period). In the 1st period, a greater percentage of RS and TS calves were observed close to the fence line (<10 m) that separated them from their dams (P < 0.0001) and vocalized more than CS calves (P < 0.0001), while in the 2nd period, RS calves had the highest cortisol concentration and vocalization rate (P < 0.05). Similarly, during the 1st period, a greater percentage of RS and TS cows were observed close to the fence line than CS cows (P < 0.0001), with TS cows vocalizing the most (P = 0.001). In the 2nd period, RS cows had greater cortisol concentration than TS (P = 0.037) and CS cows (P = 0.003). More TS and CS cows than RS were observed close to the fence line (P = 0.03 and P = 0.05). On Day 150, TS calves and cows vocalized more than RS and CS animals (P < 0.0001). Before calf-cow separation, 27 out of 45 cows were cycling (CS = 10; RS = 6; TS = 11). After separation, 12 of the remaining 18 cows resumed ovarian activity (CS = 3; RS = 5; TS = 4), and all cows were cycling after estrous synchronization treatment. The pregnancy rate was similar between CS, RS, and TS (60, 53, and 60% respectively). In conclusion, temporary separation increased calf distress response to definitive weaning even four months later, while restricted suckling seemed to reduce it.


Sujet(s)
Oestrus , Période du postpartum , Animaux , Animaux allaités , Bovins , Femelle , Grossesse , Progestérone , Sevrage
17.
Trop Anim Health Prod ; 53(1): 143, 2021 Jan 27.
Article de Anglais | MEDLINE | ID: mdl-33506365

RÉSUMÉ

Communal rearing has been reported in several mammals, including wild ungulates. However, until now, there was no evidence of any alloparental care in the Bos genus. To test the hypothesis that calves' groups are formed under the care of specific cows, a herd of 31 peri-partum zebu cows raised under pasture conditions were used. Groups of ≥ 3 individuals within a 10-m diameter were estimated using aerial pictures taken every other day at 7:00, 10:30, 13:30, 16:00, and 18:00 h, during 6 weeks. Temperament (exit speed, flight distance, intensity of reaction), age, and parity of each cow were registered. A total of 142 groups were observed, and in all of them, at least one calf was present. A total of 75% of the groups were more calves than cows, and in 65.4% of the cases, there were 1 to 3 cows with 2 to 32 calves. While there were no groups integrated only by cows, there were 3.5% integrated only with calves. The most frequent group was formed by 2 calves and 1 cow (14.8%). Parity was positively related with the number of times that a cow was observed in a group (R2 = 0.19, P = 0.01) and with the number of groups in which her calf was present (R2 = 0.16; P = 0.03). The results of the temperament tests were unrelated to the total number of groups in which a cow was observed nor the number of groups with or without its calf. It was concluded that zebu calves congregate in newborn groups in companion with one or more adults, preferably high parity cows, regardless of their temperament.


Sujet(s)
Tempérament , Animaux , Bovins , Femelle , Parité , Grossesse
18.
Semin Cell Dev Biol ; 114: 1-10, 2021 06.
Article de Anglais | MEDLINE | ID: mdl-32893132

RÉSUMÉ

Circular RNA (circRNA) is an unusual class of RNA-like structures composed by exonic and/or intronic sequences that are regulated by the backsplicing mechanism and by the spliceosome-mediated machinery. These circular transcripts tend to accumulate during aging in several human tissues, especially in the mammalian brain, and their expression is correlated with the occurrence of several human pathologies, including a broad spectrum of neurological disorders. Previous findings have also shown that circRNAs are significantly present in the neuronal tissue and are up-regulated during neurogenesis, with a significant number been derived from neural genes, suggesting these circular molecules are involved in the cellular and molecular phenotype of our brain. However, the complete biogenesis, the many types of circRNA molecules, and their involvement with neuronal phenotype and with the occurrence of pathologies are still a challenging avenue for researchers. In this updated review, we discuss the current findings of the biogenesis and the diversity of cirRNAs and their molecular involvement in neurological tissue phenotype. We also discuss how some circRNAs can act as sponge molecules, regulating the activity of microRNA expression over gene translation. Finally, we also show the correlation of altered circRNA expression in neurological disorders.


Sujet(s)
Maladies du système nerveux/physiopathologie , ARN circulaire/métabolisme , Humains , Biogenèse des organelles , Phénotype
19.
Neurochirurgie ; 67(2): 140-144, 2021 Apr.
Article de Anglais | MEDLINE | ID: mdl-32623061

RÉSUMÉ

OBJECTIVE: To report two rare cases of medulloblastoma in pregnant patients and a review of the literature. MATERIAL AND METHODS: Report of patients diagnosed with medulloblastoma during their pregnancies, who were treated with surgery and adjuvant therapy. We also reviewed other cases reported in the literature and the association made with hormonal receptors. RESULTS: Brain tumors in coincidence with pregnancy are unusual, and the incidence of medulloblastoma in pregnancy is still rarer. We found 8 cases of medulloblastomas diagnosed during pregnancy. Reports suggest that hormonal changes and increases in the levels of growth factors and angiogenic factors during pregnancy influence the rate of growth of brain tumors (not only medulloblastomas but also meningiomas or glial tumors). CONCLUSIONS: The uniqueness of these cases is their rarity. The symptoms are usually masked by the symptoms of pregnancy. At present, there is still little evidence regarding the pathogenesis and treatment of medulloblastoma in pregnancy.


Sujet(s)
Tumeurs du cervelet/imagerie diagnostique , Tumeurs du cervelet/chirurgie , Médulloblastome/imagerie diagnostique , Médulloblastome/chirurgie , Complications tumorales de la grossesse/imagerie diagnostique , Complications tumorales de la grossesse/chirurgie , Tumeurs du cervelet/sang , Femelle , Hormones sexuelles stéroïdiennes/sang , Humains , Médulloblastome/sang , Grossesse , Complications tumorales de la grossesse/sang , Jeune adulte
20.
J Biotechnol ; 323: 159-165, 2020 Nov 10.
Article de Anglais | MEDLINE | ID: mdl-32827602

RÉSUMÉ

Carotenoids (CD) are biological pigments produced for commercial purposes. Therefore, it is necessary to study and determine the optimal conditions for increased CD production. There is no consensus in the literature about the conditions that increase CD production. Some authors stated that CD will be preferentially produced at low light intensities, at this adverse condition, microorganism will increase CD production as a survival response mechanism to get more energy. Other authors have mentioned that CD concentrations increase as the light intensity supplied increases, to avoid the overexposure of light and in turn photo-inhibition. Additionally, to increase the specific CD production is also necessary to increase the amount of biomass. In this work, the ammonium concentration (high (HAC) and low (LAC)) and the low light (LL) intensity effect on the CD production was evaluated. Data showed that a high CD-specific concentration of 8.8 mg/gcell was obtained by using R. palustris ATCC 17001 under HAC and LL intensity. CD production was similar at HAC and LAC, suggesting that the light intensity has a greater effect on the specific CD concentration than the nitrogen concentration. In general, the results showed a low biomass production compared to the literature, with high CD synthesis.


Sujet(s)
Caroténoïdes/métabolisme , Lumière , Rhodopseudomonas/métabolisme , Rhodopseudomonas/effets des radiations , Composés d'ammonium/métabolisme , Biomasse , Cinétique , Rhodopseudomonas/croissance et développement
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