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Athropogenic changes have caused profound repercussions, which have led to a progressive degradation of natural resources. In the case of the Ecuadorian Amazon, the high rate of deforestation, changes in land use and extensive livestock management have led to low production rates with an eminent threat to the thermal comfort of ruminants. The present study aimed to contrasts how the use of SPs represents a viable option for the reconversion of extensive livestock farming. The current study compared the use of silvopastoral systems (SPs) versus a conventional pastoral system, as an alternative for the recovery of degraded areas. Therefore, under a completely randomized block design, Brachiaria decumbens was evaluated with three of treatments, such as Control = conventional pastoral, SPs1 = density 100 trees/ha-1 and SPs2 = 150 trees/ha-1. All environmental variables and bioclimatic indicators (temperature and radiant heat load: RHL) were shown to be mitigated under SPs (P < 0.001), which translates into better thermal comfort for ruminants (RHL; 638 vs. 1749 ± 40; P < 0.001). Although, the treatments affected all the agronomic variables of Brachiaria decumbens (P < 0.001 to 0.004), the month conditioned most of the chemical determinations (P < 0.001). This means that the use of SPs in the medium or long term could contribute to the recovery of pastures in degradation processes. Consequently, SPs as a clean production alternative would help improve aspects such as soil quality, agronomic yields, as well as greater nutritional quality of pastures. In any case, long-term studies should be performed to contrast our responses.
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Crianza de Animales Domésticos , Brachiaria , Animales , Ecuador , Crianza de Animales Domésticos/métodos , Conservación de los Recursos Naturales , Distribución Aleatoria , Estaciones del Año , Rumiantes/fisiologíaRESUMEN
Xeno-nucleic acid (XNA) aptamers based on evolvable non-natural genetic polymers hold enormous potential as future diagnostic and therapeutic agents. However, time-consuming and costly procedures requiring the purification of individual XNA sequences produced by large-scale polymerase-mediated primer extension reactions pose a major bottleneck to the discovery of highly active XNA motifs for biomedical applications. Here, we describe a straightforward approach for rapidly surveying the binding properties of XNA aptamers identified by in vitro selection. Our strategy involves preparing XNA aptamer particles in which many copies of the same aptamer sequence are distributed throughout the gel matrix of a polyacrylamide-encapsulated magnetic particle. Aptamer particles are then screened by flow cytometry to assess target binding affinity and deduce structure-activity relationships. This generalizable and highly parallel assay dramatically accelerates the pace of secondary screening by allowing a single researcher to evaluate 48-96 sequences per day.
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Aptámeros de Nucleótidos , Ácidos Nucleicos , Ácidos Nucleicos/química , Aptámeros de Nucleótidos/genética , Hidrogeles , Técnica SELEX de Producción de Aptámeros/métodos , Relación Estructura-ActividadRESUMEN
Every year, dengue is responsible for 400 million infections worldwide. Inflammation is related to the development of severe forms of dengue. Neutrophils are a heterogeneous cell population with a key role in the immune response. During viral infection, neutrophils are mainly recruited to the infection site; however, their excessive activation is linked to deleterious results. During dengue infection, neutrophils are involved in the pathogenesis through neutrophils extracellular traps production, tumor necrosis factor-alpha, and interleukin-8 secretion. However, other molecules regulate the neutrophil role during viral infection. TREM-1 is expressed on neutrophils and its activation is related to increased production of inflammatory mediators. CD10 is expressed on mature neutrophils and has been associated with the regulation of neutrophil migration and immunosuppression. However, the role of both molecules during viral infection is limited, particularly during dengue infection. Here, we report for the first time that DENV-2 can significantly increase TREM-1 and CD10 expression as well as sTREM-1 production in cultured human neutrophils. Furthermore, we observed that treatment with granulocyte-macrophage colony stimulating factor, a molecule mostly produced in severe cases of dengue, is capable of inducing the overexpression of TREM-1 and CD10 on human neutrophils. These results suggest the participation of neutrophil CD10 and TREM-1 in the pathogenesis of dengue infection.
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Virus del Dengue , Dengue , Humanos , Neutrófilos/metabolismo , Receptor Activador Expresado en Células Mieloides 1/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Neprilisina/metabolismoRESUMEN
Background: Chronic kidney disease (CKD) is a global health problem. As it progresses to end stages, renal replacement therapy is required but ultimately, the best treatment is transplantation. Decreased renal function has been associated with an inflammatory state associated to primary CKD and in kidney transplant recipients (KTRs). Objective: To establish how the serum concentrations of some cytokines, such as interleukin (IL)-2, IL-8, IL-22, IL-17α, interferon-gamma, IL-4, and transforming growth factor-ß, correlate with various CKD stages. Methods: One hundred and forty-one KTRs between the ages of 18 and 75 years were included in the study. We also included 112 live kidney donors, 37 CKD PGCKD+3, and 76 GPhealthy. Participants were grouped according to their glomerular filtration rate (GFR) and their circulating cytokine levels, previously quantified by ELISA. Results: By linear regression analysis, we established the relation of each cytokine with the GFR. Transforming growth factor-ß correlated positively with the GFR in the study population, except in healthy individuals. A negative correlation of IL-8 and IL-17α and GFR was found in all cases. Conclusions: Whether these cytokines (IL-8 and IL-17α) could be used as inflammatory biomarkers indicating CKD progression, regardless of the type of population, remains to be prospectively determined.
Contexte: L'insuffisance rénale chronique (IRC) est un problème de santé mondial. Une thérapie de remplacement rénal est nécessaire au fur et à mesure que la maladie évolue vers les stades terminaux. Mais, en définitive, le meilleur traitement reste la transplantation. La réduction de la fonction rénale a été associée à un état inflammatoire associé à l'IRC primaire; une association observée aussi chez les receveurs d'une greffe de rein. Objectif: Déterminer la façon dont les concentrations sériques de certaines cytokines, notamment IL-2, IL-8, IL-22, IL-17a, IFN-γ, IL-4 et TGF-ß, corrèlent avec divers stades de l'IRC. Méthodologie: Ont été inclus dans l'étude 141 receveurs d'une greffe rénale âgés de 18 à 75 ans, 112 donneurs vivants de rein, 37 personnes atteintes d'IRC (PGIRC+3) et 76 personnes en bonne santé (PGen santé). Les sujets ont été regroupés en fonction de leur débit de filtration glomérulaire (DFGe) et de leur taux de cytokines en circulation, quantifiés préalablement par ELISA. Résultats: Une analyse de régression linéaire a servi à établir la relation entre chaque cytokine et le DFGe. Dans la population étudiée, une corrélation positive a été observée entre TGF-ß et le DFGe, sauf chez les individus sains. Dans tous les cas, la corrélation s'est avérée négative entre le DFGe et les taux d'IL-8 et d'IL-17a. Conclusion: Il reste à déterminer prospectivement si ces cytokines (IL-8 et IL-17a) pourraient être utilisées comme biomarqueurs inflammatoires pour indiquer la progression de l'IRC, quelle que soit la population.
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Resumen La empatía es conceptualizada como la conciencia de las emociones y cogniciones de los demás y resulta importante en el contexto escolar para el favorecimiento de la convivencia y prevención de conductas agresivas. En ese sentido, el presente estudio tiene como objetivo examinar las evidencias de validez, fiabilidad e invarianza factorial de una escala breve de empatía básica (BES) en niños peruanos. Por ende, participaron 838 niños y niñas entre 8 y 12 años de edad (M = 9.95; DE = 1.13) de seis instituciones educativas, algunos colegios fueron utilizados para el análisis exploratorio y otros para confirmar. Se administró la BES que fue adaptada para niños (BES-I). Respecto al análisis de datos, se efectuó un análisis factorial exploratorio (AFE) y confirmatorio (AFC), además del análisis de invarianza factorial, para finalmente examinar la fiabilidad mediante el coeficiente omega (ω). Los resultados del AFE sugieren una medida bidimensional oblicua (cognitivo y afectivo). Del mismo modo, el AFC reafirmó estos resultados por presentar buenas bondades de ajuste (CFI ≥ .97, RMSEA ≤ .04); estos hallazgos son coherentes con los postulados teóricos que sugieren que la empatía es un constructo compuesto por factores específicos y no por un solo factor. La invarianza factorial de acuerdo con el sexo demostró que la BES-I mide lo mismo en niños y niñas y la fiabilidad obtenida mediante el coeficiente ω fue superior a .65, lo cual indica que es aceptable. Se concluye que la BES-I es un instrumento breve que puede resultar valioso en la comprensión de la empatía infantil en futuras investigaciones.
Abstract Childhood is a period where prevention and promotion actions can be carried out; therefore, the study of positive variables such as mindfulness, well-being, resilience and empathy has increased for some years. In this sense, empathy is conceptualized as the awareness of the emotions and cognitions of others in socio-emotional theoretical models; additionally, its study is important in the school context for the promotion of coexistence and prevention of aggressive behavior. Likewise, women are known to present higher empathy prevalence than men. Within the perspectives of this construct related to the cognitive and affective states, it became the most relevant in various studies and measurement instruments; despite this, there is a lack of brief instruments to measure empathy in the Latin American context. In this sense, this study aims to examine the evidence of validity, reliability and factor invariance of a short Basic Empathy Scale (BES) in Peruvian children. For these purposes, 838 children between 8-12 years old (M = 9.95; SD = 1.13) from six schools participated, some of them were used for exploratory analysis and others for confirmation. Likewise, eleven professionals from the clinical field and with experience in children's issues participated and applied the two criteria-based BES: relevance and representativeness. Prior to this, ten children were interviewed to verify the clarity of the items. After this procedure, trained research assistants created a version of the BES for children (BES-I) for children in their respective classrooms; who also requested parental authorization by signing an informed consent. The data was analyzed by R statistical software of free access using packages such as 'psych', 'lavaan', 'MBESS', 'semTools'; two factor analyses were performed; one, exploratory (AFE) and two, confirmatory (AFC), in a third moment a multigroup analysis was performed to evaluate to what extent the factor structure is invariant in the subgroups of males and females; finally, reliability was calculated using the omega coefficient (ω). The results show that the items have the representativeness and relevance in their content according to eleven experts in clinical psychology, whose responses were quantified by V of Aiken reaching values higher than .70. The internal structure in the AFE indicated the presence of two related factors (cognitive and affective) that explain 35 % of the model variance. Similarly, the AFC verified these results by showing optimal goodness of fit (IFC ≥ .97, RMSEA ≤ .04) in the two-factor model; these empirical findings are consistent with theoretical assumptions suggesting that empathy is a construct comprising specific factors rather than a single factor. As for the multi-group analysis according to sex, the invariance of the BES-I was evidenced, when observing that the differences between the base or configuration model and those with restricted thresholds, loads, variance and covariance are minimally recommended; in that way, the BES-I is established to measure the same in boys and girls; finally, regarding the reliability in the two-factor model, the coefficient ω is observed to exceed .65 for both the cognitive factor (ω = .66) and the affective factor (ω = .66). It is concluded that the BES-I is a brief instrument to be interpreted in a two-dimensional oblique way, taking as reference the theoretical cognitive-affective perspective; thus, the validity evidence of the BES-I is valuable for the understanding of child empathy in future Latin American researches.
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African swine fever virus (ASFV) causes a virulent, deadly infection in wild and domestic swine and is currently causing a pandemic covering a contiguous geographical area from Central and Eastern Europe to Asia. No commercial vaccines are available to prevent African swine fever (ASF), resulting in devastating economic losses to the swine industry. The most advanced vaccine candidates are live attenuated strains developed using a genetically modified virulent parental virus. Recently, we developed a vaccine candidate, ASFV-G-ΔI177L, by deleting the I177L gene from the genome of the highly virulent ASFV pandemic strain Georgia (ASFV-G). ASFV-G-ΔI177L is safe and highly efficacious in challenge studies using parental ASFV-G. Large-scale production of ASFV-G-ΔI177L has been limited because it can replicate efficiently only in primary swine macrophages. Here, we present the development of an ASFV-G-ΔI177L derivative strain, ASFV-G-ΔI177L/ΔLVR, that replicates efficiently in a stable porcine cell line. In challenge studies, ASFV-G-ΔI177L/ΔLVR maintained the same level of attenuation, immunogenic characteristics, and protective efficacy as ASFV-G-ΔI177L. ASFV-G-ΔI177L/ΔLVR is the first rationally designed ASF vaccine candidate that can be used for large-scale commercial vaccine manufacture. IMPORTANCE African swine fever is currently causing a pandemic resulting in devastating losses to the swine industry. Experimental ASF vaccines rely on the production of vaccine in primary swine macrophages, which are difficult to use for the production of a vaccine on a commercial level. Here, we report a vaccine for ASFV with a deletion in the left variable region (LVR). This deletion allows for growth in stable cell cultures while maintaining the potency and efficacy of the parental vaccine strain. This discovery will allow for the production of an ASF vaccine on a commercial scale.
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Virus de la Fiebre Porcina Africana/inmunología , Fiebre Porcina Africana/prevención & control , Vacunas Virales/inmunología , Fiebre Porcina Africana/inmunología , Virus de la Fiebre Porcina Africana/genética , Animales , Técnicas de Cultivo de Célula , Línea Celular , Inmunogenicidad Vacunal , Macrófagos/virología , Pandemias , Eliminación de Secuencia , Porcinos , Vacunas Atenuadas/genética , Vacunas Atenuadas/inmunología , Vacunas Virales/genética , Cultivo de Virus/métodos , Replicación ViralRESUMEN
The classical swine fever virus (CSFV) glycoprotein E2 is the major structural component of the virus particle. E2 is involved in several functions, such as virus adsorption to the cell, the elicitation of protective immune responses, and virus virulence in swine. Using a yeast two-hybrid system, we previously identified the swine host protein Torsin-1A, an ATPase protein residing in the endoplasmic reticulum and inner nucleus membrane of the cell, as a specific binding partner for E2. The interaction between Torsin-1A and E2 proteins was confirmed to occur in CSFV-infected swine cells using three independent methods: coimmunoprecipitation, confocal microscopy, and proximity ligation assay (PLA). Furthermore, the E2 residue critical to mediate the protein-protein interaction with Torsin-1A was identified by a reverse yeast two-hybrid assay using a randomly mutated E2 library. A recombinant CSFV E2 mutant protein with a Q316L substitution failed to bind swine Torsin-1A in the yeast two-hybrid model. In addition, a CSFV infectious clone harboring the E2 Q316L substitution, although expressing substantial levels of E2 protein, repetitively failed to produce virus progeny when the corresponding RNA was transfected into susceptible SK6 cells. Importantly, PLA analysis of the transfected cells demonstrated an abolishment of the interaction between E2 Q316L and Torsin-1A, indicating a critical role for that interaction during CSFV replication.IMPORTANCE Structural glycoprotein E2 is an important structural component of the CSFV particle. E2 is involved in several virus functions, particularly virus-host interactions. Here, we characterized the interaction between CSFV E2 and swine protein Torsin-1A during virus infection. The critical amino acid residue in E2 mediating the interaction with Torsin-1A was identified and the effect of disrupting the E2-Torsin-1A protein-protein interaction was studied using reverse genetics. It is shown that the amino acid substitution abrogating E2-Torsin-1A interaction constitutes a lethal mutation, demonstrating that this virus-host protein-protein interaction is a critical factor during CSFV replication. This highlights the potential importance of the E2-Torsin-1A protein-protein interaction during CSFV replication and provides a potential pathway toward blocking virus replication, an important step toward the potential development of novel virus countermeasures.
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Virus de la Fiebre Porcina Clásica/fisiología , Chaperonas Moleculares/metabolismo , Proteínas del Envoltorio Viral/metabolismo , Sustitución de Aminoácidos , Animales , Línea Celular , Virus de la Fiebre Porcina Clásica/metabolismo , Interacciones Huésped-Patógeno , Chaperonas Moleculares/genética , Mutación , Unión Proteica , Proteínas Recombinantes/metabolismo , Porcinos , Técnicas del Sistema de Dos Híbridos , Proteínas del Envoltorio Viral/química , Proteínas del Envoltorio Viral/genética , Replicación ViralRESUMEN
INTRODUCCIÓN: La torsión aislada de la trompa de Falopio ocurre en aproximadamente una de cada 50.000 a 1.500.000 mujeres, por ende, es una afección extremadamente rara. Fue originalmente descrita por Bland-Sutton en 1890. El cuadro clínico suele ser inespecífico y puede simular una amplia variedad de dolencias. CASO CLÍNICO: Paciente de 18 años de edad que acude al servicio de urgencias por dolor abdominal intenso, la cual se decide ingresar por cuadro agudo doloroso abdominal de posible etiología ginecológica, se realiza laparoscopía de urgencia por la posibilidad de un cuadro de torsión quística, durante esta se observa una imagen laparoscópica de la trompa izquierda violácea y torcida, además un quiste paratubárico hemorrágico, de color violacio; por las características laparoscópicas de la trompa y el quiste paratubárico que se relacionan con necrosis de estos elementos, se decide realizar a la paciente una anexectomía total izquierda con cistectomía del quiste paratubárico. DISCUSIÓN: La rotación de la trompa alrededor de su pedículo vascular es el evento fisiopatológico descrito, lo que provoca inicialmente la obstrucción del retorno venoso y linfático, con el consiguiente edema, ingurgitación y trombosis. Si la torsión progresa, y no se resuelve, se ve comprometida la vascularización arterial y se desencadena la necrosis del órgano y, finalmente la instauración de peritonitis, la conducta se basa en la viabilidad de la trompa: si no tiene signos de necrosis, la conducta indicada es destorcerla, si ya aparecieron signos de necrosis deberá ser extirpada.
INTRODUCTION: Isolated torsion of the Fallopian tube occurs in approximately one in every 50,000 to 1,500,000 women, therefore, it is an extremely rare condition. It was originally described by Bland-Sutton in 1890. The clinical picture is usually nonspecific and can mimic a wide variety of ailments. CLINICAL CASE: An 18-year-old patient who came to the emergency service for intense abdominal pain, which was decided to enter due to acute abdominal pain of possible gynecological etiology, an emergency laparoscopy was performed due to the possibility of a cystic torsion condition, During this, a laparoscopic image of the violaceous and crooked left tube is observed, as well as, a hemorrhagic paratubal cyst, violet in color; Due to the laparoscopic characteristics of the tube and the paratubal cyst that are related to necrosis of these elements, it was decided to perform a total left adnexectomy with cystectomy of the paratubal cyst. DISCUSSION: Rotation of the tube around its vascular pedicle is the described pathophysiological event, which initially causes obstruction of venous and lymphatic return, with the consequent edema, engorgement and thrombosis. If the torsion progresses and does not resolve, the arterial vascularization is compromised and the necrosis of the organ is triggered and, finally, the establishment of peritonitis, the behavior is based on the viability of the tube: if there are no signs of necrosis, the indicated conduct is to untwist it, if signs of necrosis have already appeared, it must be removed.
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Humanos , Femenino , Embarazo , Adolescente , Quiste Paraovárico/cirugía , Anomalía Torsional/cirugía , Enfermedades de las Trompas Uterinas/cirugía , Laparoscopía/métodos , Urgencias Médicas , NecrosisRESUMEN
AIMS: Trimethylamine N-oxide (TMAO), choline and betaine serum levels have been associated with metabolic diseases including type 2 diabetes (T2D) and non-alcoholic fatty liver disease (NAFLD). These associations could be mediated by insulin resistance. However, the relationships among these metabolites, insulin resistance and NAFLD have not been thoroughly investigated. Moreover, it has recently been suggested that TMAO could play a role in NAFLD by altering bile acid metabolism. We examined the association between circulating TMAO, choline and betaine levels and NAFLD in obese subjects. METHODS: Serum TMAO, choline, betaine and bile acid levels were measured in 357 Mexican obese patients with different grades of NAFLD as determined by liver histology. Associations of NAFLD with TMAO, choline and betaine levels were tested. Moreover, association of TMAO levels with non-alcoholic steatohepatitis (NASH) was tested separately in patients with and without T2D. RESULTS: TMAO and choline levels were significantly associated with NAFLD histologic features and NASH risk. While increased serum TMAO levels were significantly associated with NASH in patients with T2D, in non-T2D subjects this association lost significance after adjusting for sex, BMI and HOMA2-IR. Moreover, circulating secondary bile acids were associated both with increased TMAO levels and NASH. CONCLUSIONS: In obese patients, circulating TMAO levels were associated with NASH mainly in the presence of T2D. Functional studies are required to evaluate the role of insulin resistance and T2D in this association, both highly prevalent in NASH patients.
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Diabetes Mellitus Tipo 2 , Metilaminas/sangre , Enfermedad del Hígado Graso no Alcohólico , Adulto , Betaína/sangre , Ácidos y Sales Biliares/sangre , Biomarcadores/sangre , Biopsia , Colina/sangre , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/epidemiología , Femenino , Humanos , Resistencia a la Insulina , Hígado/patología , Masculino , Americanos Mexicanos , Persona de Mediana Edad , Enfermedad del Hígado Graso no Alcohólico/complicaciones , Enfermedad del Hígado Graso no Alcohólico/epidemiología , Obesidad/complicaciones , Obesidad/epidemiologíaRESUMEN
BACKGROUND: Tuberculosis (TB) is the leading opportunistic infection in children with human immunodeficiency virus (HIV), but is uncommon in low prevalence regions. We aim to describe the changing epidemiology and clinical presentation of TB-HIV co-infection in a cohort of HIV-infected children in Spain.METHODS: Children diagnosed with TB between 1995 and 2016 in the paediatric HIV cohort were identified. The incidence and clinical presentation were compared in three periods: 1995-1999 (P1, before initiation of combined antiretroviral therapy, cART), 2000-2009 (P2, increase in immigration), and 2010-2016 (P3, decrease in immigration).RESULTS: We included 29 TB cases among 1183 children aged <18 years (2.4%, 243/100 000 person-years). The proportion was stable in P1 and P2 (1.3%), but decreased in P3 (0.8%). The median age at TB diagnosis was 6.4 years (IQR 4-10.6); most children in P3 were aged >10 years (20% vs. 23.1% vs. 83.3%, P = 0.01). TB was diagnosed at HIV presentation in 11/29 children (37.9%). Foreign-born children accounted for respectively 0%, 8% and 67% of the total number of children in each period (P ≤ 0.0001). One third had extrapulmonary TB; four children died (13.8%).CONCLUSION: In our cohort, the incidence of TB-HIV co-infection decreased with decline in immigration. In regions with adequate cART coverage and low TB transmission, paediatric TB-HIV coinfection is uncommon, but associated with significant morbidity. Strategies for TB surveillance, diagnosis and treatment in this vulnerable population should be reinforced.
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Coinfección , Infecciones por VIH , Tuberculosis , Adolescente , Niño , Estudios de Cohortes , Coinfección/epidemiología , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/epidemiología , Humanos , Estudios Retrospectivos , España/epidemiología , Tuberculosis/diagnóstico , Tuberculosis/tratamiento farmacológico , Tuberculosis/epidemiologíaRESUMEN
The E2 protein in classical swine fever (CSF) virus (CSFV) is the major virus structural glycoprotein and is an essential component of the viral particle. E2 has been shown to be involved in several functions, including virus adsorption, induction of protective immunity, and virulence in swine. Using the yeast two-hybrid system, we previously identified a swine host protein, dynactin subunit 6 (DCTN6) (a component of the cell dynactin complex), as a specific binding partner for E2. We confirmed the interaction between DCTN6 and E2 proteins in CSFV-infected swine cells by using two additional independent methodologies, i.e., coimmunoprecipitation and proximity ligation assays. E2 residues critical for mediating the protein-protein interaction with DCTN6 were mapped by a reverse yeast two-hybrid approach using a randomly mutated E2 library. A recombinant CSFV mutant, E2ΔDCTN6v, harboring specific substitutions in those critical residues was developed to assess the importance of the E2-DCTN6 protein-protein interaction for virus replication and virulence in swine. CSFV E2ΔDCTN6v showed reduced replication, compared with the parental virus, in an established swine cell line (SK6) and in primary swine macrophage cultures. Remarkably, animals infected with CSFV E2ΔDCTN6v remained clinically normal during the 21-day observation period, which suggests that the ability of CSFV E2 to bind host DCTN6 protein efficiently during infection may play a role in viral virulence.IMPORTANCE Structural glycoprotein E2 is an important component of CSFV due to its involvement in many virus activities, particularly virus-host interactions. Here, we present the description and characterization of the protein-protein interaction between E2 and the swine host protein DCTN6 during virus infection. The E2 amino acid residues mediating the interaction with DCTN6 were also identified. A recombinant CSFV harboring mutations disrupting the E2-DCTN6 interaction was created. The effect of disrupting the E2-DCTN6 protein-protein interaction was studied using reverse genetics. It was shown that the same amino acid substitutions that abrogated the E2-DCTN6 interaction in vitro constituted a critical factor in viral virulence in the natural host, domestic swine. This highlights the potential importance of the E2-DCTN6 protein-protein interaction in CSFV virulence and provides possible mechanisms of virus attenuation for the development of improved CSF vaccines.
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Virus de la Fiebre Porcina Clásica/genética , Peste Porcina Clásica/virología , Complejo Dinactina/genética , Regulación de la Expresión Génica , Interacciones Huésped-Patógeno/genética , Proteínas del Envoltorio Viral/genética , Animales , Sitios de Unión , Línea Celular , Peste Porcina Clásica/mortalidad , Peste Porcina Clásica/patología , Virus de la Fiebre Porcina Clásica/metabolismo , Virus de la Fiebre Porcina Clásica/patogenicidad , Complejo Dinactina/metabolismo , Células Epiteliales/metabolismo , Células Epiteliales/virología , Biblioteca de Genes , Macrófagos/metabolismo , Macrófagos/virología , Mutación , Cultivo Primario de Células , Unión Proteica , Transducción de Señal , Análisis de Supervivencia , Porcinos , Técnicas del Sistema de Dos Híbridos , Proteínas del Envoltorio Viral/metabolismo , Replicación ViralRESUMEN
We present an analytical model for the role of hydrogen bonding on the spin-orbit coupling of a model DNA molecule. Here, we analyze in detail the electric fields due to the polarization of the hydrogen bond on the DNA base pairs and derive, within a tight binding analytical band folding approach, an intrinsic Rashba coupling which should dictate the order of the spin active effects in the chiral-induced spin selectivity effect. The coupling found is ten times larger than the intrinsic coupling estimated previously and points out to the predominant role of hydrogen bonding in addition to chirality in the case of biological molecules. We expect similar dominant effects in oligopeptides, where the chiral structure is supported by hydrogen-bonding and bears on orbital carrying transport electrons.
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ADN/química , Modelos Químicos , Transporte de Electrón , Enlace de Hidrógeno , Oligopéptidos/químicaRESUMEN
This is a report of a study of the nonlinear optical properties of samples based on multiple Al2O3/ZnO bilayers fabricated by atomic layer deposition (ALD) in silica. The multi-layer configuration for samples consists of alternated layers of constant thickness of Al2O3 (Δx) and ZnO (Δy) nanolaminates with a total thickness of â¼ 500 nm. The physical properties of the samples were characterized by means of TEM, spectrophotometry and variable angle spectroscopic ellipsometry. The absorptive and refractive contributions to the nonlinearity of the samples were studied by means of z-scan technique using a 100 fs at 800 nm. The nonlinear parameters, ß and n2, are studied using different values of the layers thickness, Δx and Δy, in the nanolaminated stack. The possible applications in optical signal processing system are discussed by means of the figures of merit W and T.
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Envelope glycoprotein E2 of Classical Swine Fever Virus (CSFV) is involved in several critical virus functions. To analyze the role of E2 in virus replication, a series of recombinant CSFVs harboring chimeric forms of E2 CSFV and Bovine viral diarrhea virus (BVDV) were created and tested for their ability to infect swine or bovine cell lines. Substitution of native CSFV E2 by BVDV E2 abrogates virus replication in both cell lines. Substitution of individual domains in CSFV Brescia E2 by the homologous from BVDV produces chimeras that efficiently replicate in SK6 cells with the exception of a chimera harboring BVDV E2 residues 93-168. Further mapping revealed a critical area in E2 required for CSFV replication in SK6 cells between protein residues 136-156. This is the first report categorically defining a discrete portion of E2 as essential to pestivirus infection in susceptible cells.
Asunto(s)
Virus de la Fiebre Porcina Clásica/fisiología , Virus de la Diarrea Viral Bovina/fisiología , Infecciones por Pestivirus/virología , Dominios Proteicos/genética , Proteínas del Envoltorio Viral/química , Replicación Viral/genética , Secuencia de Aminoácidos , Sustitución de Aminoácidos , Animales , Bovinos , Línea Celular , Virus de la Fiebre Porcina Clásica/genética , Virus de la Fiebre Porcina Clásica/patogenicidad , Virus de la Diarrea Viral Bovina/genética , Virus de la Diarrea Viral Bovina/patogenicidad , Especificidad del Huésped , Virus Reordenados/genética , Virus Reordenados/patogenicidad , Virus Reordenados/fisiología , Porcinos , Proteínas del Envoltorio Viral/genética , Proteínas del Envoltorio Viral/metabolismoRESUMEN
Nonstructural protein 2B of foot-and-mouth disease (FMD) virus (FMDV) is comprised of a small, hydrophobic, 154-amino-acid protein. Structure-function analyses demonstrated that FMDV 2B is an ion channel-forming protein. Infrared spectroscopy measurements using partially overlapping peptides that spanned regions between amino acids 28 and 147 demonstrated the adoption of helical conformations in two putative transmembrane regions between residues 60 and 78 and between residues 119 and 147 and a third transmembrane region between residues 79 and 106, adopting a mainly extended structure. Using synthetic peptides, ion channel activity measurements in planar lipid bilayers and imaging of single giant unilamellar vesicles (GUVs) revealed the existence of two sequences endowed with membrane-porating activity: one spanning FMDV 2B residues 55 to 82 and the other spanning the C-terminal region of 2B from residues 99 to 147. Mapping the latter sequence identified residues 119 to 147 as being responsible for the activity. Experiments to assess the degree of insertion of the synthetic peptides in bilayers and the inclination angle adopted by each peptide regarding the membrane plane normal confirm that residues 55 to 82 and 119 to 147 of 2B actively insert as transmembrane helices. Using reverse genetics, a panel of 13 FMD recombinant mutant viruses was designed, which harbored nonconservative as well as alanine substitutions in critical amino acid residues in the area between amino acid residues 28 and 147. Alterations to any of these structures interfered with pore channel activity and the capacity of the protein to permeabilize the endoplasmic reticulum (ER) to calcium and were lethal for virus replication. Thus, FMDV 2B emerges as the first member of the viroporin family containing two distinct pore domains.IMPORTANCE FMDV nonstructural protein 2B is able to insert itself into cellular membranes to form a pore. This pore allows the passage of ions and small molecules through the membrane. In this study, we were able to show that both current and small molecules are able to pass though the pore made by 2B. We also discovered for the first time a virus with a pore-forming protein that contains two independent functional pores. By making mutations in our infectious clone of FMDV, we determined that mutations in either pore resulted in nonviable virus. This suggests that both pore-forming functions are independently required during FMDV infection.
Asunto(s)
Permeabilidad de la Membrana Celular , Virus de la Fiebre Aftosa/metabolismo , Fiebre Aftosa/metabolismo , Membrana Dobles de Lípidos/metabolismo , Proteínas no Estructurales Virales/metabolismo , Replicación Viral , Secuencia de Aminoácidos , Animales , Células Cultivadas , Cricetinae , Fiebre Aftosa/genética , Fiebre Aftosa/virología , Virus de la Fiebre Aftosa/genética , Transporte Iónico , Mutación , Fragmentos de Péptidos/genética , Fragmentos de Péptidos/metabolismo , Dominios Proteicos , Homología de Secuencia , Proteínas no Estructurales Virales/genéticaRESUMEN
Los analistas del discurso crítico (ADC) se refieren al lenguaje como una práctica social. Implica una relación dialéctica entre un evento discursivo particular y la situación(es), institución(es) y estructura social(es) que lo enmarca. Así, el discurso es socialmente constituido como también condicionado socialmente, y desde esa situación lo ideológico y el poder se sitúan en el lenguaje condicionando lo que puede decirse o no. El ADC, particularmente de N. Fairclough, con su modelo teórico-metodológico 3-D puede apoyar a investigadores en develar las relaciones de dominio y poder que conlleva la relación dialéctica de eventos discursivos en un fenómeno de salud que sea problemático a nivel social. Objetivo: Este artículo de revisión de narrativa trata sobre el análisis crítico del discurso (ADC) y expone los preceptos más importantes que lo distinguen. Se focaliza en el modelo 3-D de Norman Fairclough para detallar su metodología y su desarrollo de análisis descriptivo, interpretativo y social, con algunos ejemplos de su modelo aplicados en salud.
The analysts of the critical discourse refer language as being a social practice. This implies a dialectic relationship between a discursive event in particular, and the situations, institutions, and social structures framing it. Thus, the discourse is socially constituted and conditioned, and from this perspective, ideology and power become part of the conditioned language in terms of what can be said and what cannot. The analysis of the critical discourse, in particular that of N. Fairclough with its theoretical-methodological 3-D model, can support researchers to revealing the relationships of power and dominion in the dialectic dynamics among discursive events in a health phenomenon with social problematic. Objective: This article of narrative review addresses the critical analysis of the discourse, highlighting its most important characteristics. The review is focused on the Norman Fairclough's 3-D model, detailing its methodology and descriptive, interpretative, and social analysis development through some examples related to the area of health.
Os analistas do discurso crítico (ADC) referem-se à linguagem como uma prática social. Envolve uma relação dialética entre um evento discursivo particular e a situação(ões), instituição(ões) e estrutura social(ais) que o enquadra. Assim, o discurso é socialmente constituído como também condicionado socialmente, e desde essa situação o ideológico e o poder situam-se na linguagem condicionada o que pode se dizer ou não. O ADC, particularmente de N. Fairclough, com seu modelo teórico-metodológico 3-D pode apoiar a pesquisadores em desvelar as relações de domínio e poder que implica a relação dialética de eventos discursivos em um fenómeno de saúde que seja problemático a nível social. Objetivo: Este artigo de revisão de narrativa trata sobre a análise crítica do discurso (ADC) e expõe os preceitos mais importantes que o distinguem. Focaliza-se no modelo 3-D de Norman Fairclough para detalhar sua metodologia e seu desenvolvimento de análise descritiva, interpretativa e social, com alguns exemplos de seu modelo aplicados em saúde.
Asunto(s)
Humanos , Masculino , Femenino , Discurso , Estructura Social , LenguajeRESUMEN
A compositional re-assessment of the microbiota present in commercial cucumber fermentation using culture independent and dependent methods was conducted, with emphasis on lactic acid bacteria (LAB). Two commercial cucumber fermentation tanks were monitored by measuring pH, dissolved oxygen and temperature, and used as sources of samples for microbial plating, genomic DNA extraction and measurement of organic acids and carbohydrates by HPLC. Six additional commercial tanks were included to identify the dominant microorganisms using molecular methods. A comparative analysis of the publically available genome sequences corresponding to the LAB found in cucumber fermentations was completed to gain an understanding of genomic features possibly enabling dominance. Analyses of the microbiota suggest Lactobacillales prevail in cucumber fermentations, including in order of prevalence Lactobacillus pentosus, Lb. plantarum, Lb. brevis, Weissella spp., Pediococcus ethanolidurans, Leuconostoc spp. and Lactococcus spp. It was observed that Lb. pentosus and Lb. plantarum have comparatively larger genomes, higher gene counts, uniquely distribute the ribosomal clusters across the genome as opposed to close to the origin of replication, and possess more predicted amino acids prototrophies and selected biosynthesis related genes. It is theorized that Lb. pentosus and Lb. plantarum dominance in cucumber fermentations is the result of their genetic make-up.
Asunto(s)
Cucumis sativus/microbiología , Fermentación , Microbiología de Alimentos , Lactobacillales/genética , Lactobacillales/fisiología , ADN Bacteriano , Genómica , Microbiología Industrial , Lactobacillales/clasificación , Lactobacillales/aislamiento & purificación , Lactococcus/genética , Lactococcus/aislamiento & purificación , Lactococcus/fisiología , Leuconostoc/genética , Leuconostoc/aislamiento & purificación , Leuconostoc/fisiología , Microbiota/genética , Microbiota/fisiología , Pediococcus/genética , Pediococcus/aislamiento & purificación , Pediococcus/fisiología , Reacción en Cadena de la Polimerasa , Análisis de Secuencia de ADNRESUMEN
Abstract Mangrove communities were selected in the state of Santa Catarina, Brazil, near their southernmost limit of distribution, to study mineral nutrient relation in soils and plants. Communities included three true mangrove species, Rhizophora mangle, Laguncularia racemosa and Avicennia germinans, and two associated species, the fern Acrostichum danaeifolium, and the grass Spartina densiflora. The sites included communities in the lower Río Tavares near Florianopolis city, Sonho beach near Palhoça city, and the Santo Antonio lagoon. These sites included a full range of mangroves under humid climate where winter temperatures, instead of salinity, may be the main factor regulating their productive capacity and species composition. Soil salinity was determined by the concentration of soluble Na, and soil C and N were linearly correlated indicating their association in organic matter. Tavares site showed higher specific conductivity, and concentrations of Na and Mg in the soil layer below 40 cm depth, indicating larger influence of marine water. Isotopic signature of C increased with soil depth suggesting that microorganisms decomposing organic matter are releasing 13C depleted CO2. Nitrogen isotopic signature decreased with soil depth, indicating enrichment in 15N possibly as a result of denitrification in the upper soil layers. Mineral elements in leaf tissues showed A. schaueriana with higher concentrations of N, P, Na, K, Cu, Zn, and Na/Ca ratio. Spartina densiflora was characterized by the lowest N and K concentrations, and the highest concentrations of Al and Fe. Rhizophora mangle and L. racemosa had the highest Ca concentrations. Carbon isotopic signatures identified S. densiflora as a C4 plant, and A. schaueriana as the mangrove species occupying comparatively more water stressed microsites than the rest. Leaf nitrogen isotopic signatures were positive, in correspondence with the soil values. The results support the hypothesis that sites sampled were comparatively fertile, because sediment transport through fresh water run-off is predominant in humid coasts, and therefore plants were not limited by nutrient supply, nor particularly stressed by soil salinity.
Resumo Foram selecionadas florestas de mangue próximas ao limite sul de distribuição dos manguezais, no estado de Santa Catarina, Brasil, para o estudo do conteúdo de nutrientes no solo e em tecido vegetal. As comunidades estudadas eram compostas por três espécies típicas de mangue: Rhizophora mangle, Laguncularia racemosa e Avicennia germinans, e duas espécies associadas: a samambaia-do-brejo, Acrostichum danaeifolium, e a herbácea Spartina densiflora. Os locais de estudo incluiram comunidades no curso inferior do Rio Tavares na cidade de Florianópolis; Praia do Sonho, próxima à cidade de Palhoça e a Lagoa de Santo Antonio. Esses locais incluiram manguezais submetidos a clima úmido, onde as temperaturas do inverno, mais do que a salinidade, são o principal fator regulador da capacidade produtiva do sistema e da composição de espécies. A salinidade do solo foi determinada pela concentração de Na solúvel. Os conteúdos de Carbono e Nitrogênio no solo apresentaram correlação linear, indicando sua associação na matéria orgânica. A área do Rio Tavares apresentou maior influência marinha evidenciada pelas altas condutividade específica e concentrações de Na e Mg nas camadas do solo abaixo de 40 cm de profundidade. A assinatura isotópica do C aumentou com a profundidade no solo, o que sugere que microorganismos decompositores da matéria orgânica estão liberando CO2 pobre em 13C. A assinatura isotópica do Nitrogênio diminui com a profundidade do solo, indicando enriquecimento em 15N, possivelmente como resultado de processo de denitrificação nos níveis superiores do solo. Os tecidos foliares de A. schaueriana apresentaram as maiores concentrações de N, P, Na, K, Cu, Zn, e da razão Na/Ca. Spartina densiflora apresentou as menores concentrações de N e K e as maiores concentrações de Al e Fe. Rhizophora mangle e L. racemosa apresentaram as maiores concentrações de Ca. Os resultados da assinatura isotópica de Carbono identificam S. densiflora como uma planta C4 e A. schaueriana como a espécie de mangue que ocupa os locais com maior estresse hidrico. As assinaturas isotópicas do Nitrogênio foram positivas, estando de acordo com os valores observados para o solo. Os resultados sustentam a hipótese de que os locais estudados são fertéis, pois o escoamento superficial de água doce é predominante em costas úmidas e, portanto, as plantas não estão sujeitas à limitação por aporte de nutrientes e não estão submetidas a estresse salino.
Asunto(s)
Suelo/química , Isótopos de Carbono/análisis , Magnoliopsida/química , Isótopos de Nitrógeno/análisis , Brasil , Hojas de la Planta/química , SalinidadRESUMEN
La disfagia es una alteración del proceso deglutorio que afecta la seguridad, eficacia y calidad de la alimentación. Una de las estrategias más utilizadas para su intervención es la modificación de la viscosidad de los alimentos, sin embargo, la metodología empleada para determinarla es subjetiva y no está estandarizada. Esta investigación buscó establecer el dominio de los fonoaudiólogos para determinar el tipo de viscosidad. Se utilizaron 12 muestras de alimentos líquidos, cuyas viscosidades fueron determinadas objetivamente con un viscosímetro rotacional, clasificándolos bajo las categorías: fino, néctar, miel y pudín. Posteriormente, cuarenta fonoaudiólogos que se desempeñan en el área de los trastornos de la deglución en centros de salud de la Región Metropolitana en Santiago de Chile, evaluaron subjetivamente las 12 muestras. Con esta información se realizó un estudio comparativo objetivo/subjetivo para establecer el dominio de los profesionales. Los participantes lograron 66,87 por ciento de efectividad en la valoración del grado de viscosidad de las muestras, con un mejor rendimiento para aquellas viscosidades tipo fino y pudín. La repetibilidad intrasujeto fue superior a 75 por ciento para el 60 por ciento de la muestra. Existen además indicadores de que el tiempo de ejercicio profesional incidiría positivamente en estas capacidades, no así el nivel de perfeccionamiento. Por último, se establece que los fonoaudiólogos evaluados poseen un dominio regular para determinar el grado de viscosidad de alimentos líquidos, pero este no es homogéneo. Se hace necesario incentivar el conocimiento y manejo adecuado en este tema, en búsqueda de consensuar procedimientos y criterios que permitan una mayor estandarización al respecto.
Dysphagia is a disruption in the swallowing process which hinders movement of food, affecting the safety, efficiency and quality of feeding. Treatment includes different strategies, with viscosity modification being one of the most used strategies nowadays. However, the methodology used to determine food viscosity is subjective and not standardized. In this regard, this study seeks to establish the speech pathologists skills in determining the different types of food viscosity. Twelve samples of liquid foods were used, whose viscosities were determined objectively with a rotational viscometer. Then, the samples of liquid foods were classified into four categories: thin liquid, nectar, honey, and pudding. Forty speech pathologists working with patients diagnosed with dysphagia at health centers in the Metropolitan Region, Chile, subjectively evaluated the samples of liquid foods. Finally, an objective/subjective comparative study was performed to determine their competence in identifying the different types of food viscosity. Near 66,87 percent of the participants performed well in the task. Participants performed better in determining thin and pudding viscosities. Over 75 percent of intra-subject repeatability was obtained for 60 percent of the sample. Unlike postgraduate studies, it could be observed that professional experience has a positive impact on these skills. Finally, the results of this study indicate that the participants have intermediate skills in determining the degree of viscosity of liquid food. However, this is not homogeneous, and therefore, it is necessary to enhance our understanding and proper management of dysphagia. Agreement on standard procedures is also necessary.