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BACKGROUND: Nitric oxide is produced by different nitric oxide synthases isoforms. NO activates two signaling pathways, one dependent on soluble guanylate cyclase and protein kinase G, and other where NO post-translationally modifies proteins through S-nitrosylation, which is the modification induced by NO in free-thiol cysteines in proteins to form S-nitrosothiols. High levels of NO have been detected in blood of breast cancer patients and increased NOS activity has been detected in invasive breast tumors compared to benign or normal breast tissue, suggesting a positive correlation between NO biosynthesis, degree of malignancy and metastasis. During metastasis, the endothelium plays a key role allowing the adhesion of tumor cells, which is the first step in the extravasation process leading to metastasis. This step shares similarities with leukocyte adhesion to the endothelium, and it is plausible that it may also share some regulatory elements. The vascular cell adhesion molecule-1 (VCAM-1) expressed on the endothelial cell surface promotes interactions between the endothelium and tumor cells, as well as leukocytes. Data show that breast tumor cells adhere to areas in the vasculature where NO production is increased, however, the mechanisms involved are unknown. RESULTS: We report that the stimulation of endothelial cells with interleukin-8, and conditioned medium from breast tumor cells activates the S-nitrosylation pathway in the endothelium to induce leukocyte adhesion and tumor cell extravasation by a mechanism that involves an increased VCAM-1 cell surface expression in endothelial cells. We identified VCAM-1 as an S-nitrosylation target during this process. The inhibition of NO signaling and S-nitrosylation blocked the transmigration of tumor cells through endothelial monolayers. Using an in vivo model, the number of lung metastases was inhibited in the presence of the S-nitrosylation inhibitor N-acetylcysteine (NAC), which was correlated with lower levels of S-nitrosylated VCAM-1 in the metastases. CONCLUSIONS: S-Nitrosylation in the endothelium activates pathways that enhance VCAM-1 surface localization to promote binding of leukocytes and extravasation of tumor cells leading to metastasis. NAC is positioned as an important tool that might be tested as a co-therapy against breast cancer metastasis.

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The "timed inspiratory effort" (TIE) index, a new predictor of weaning outcome, normalizes the maximal inspiratory pressure with the time required to reach this value up to 60 s, incorporating the time domain into the assessment of inspiratory muscle function. The objective of this study was to determine whether the TIE predicts successful extubation at a similar rate as the T-piece trial with less time required. A non-inferiority randomized controlled trial was performed with ICU subjects eligible for weaning. The participants were allocated to the TIE or the T-piece groups. The primary outcome was successful weaning, and the main secondary outcome was ICU mortality. Eighty participants of each group were included in the final analysis. Time from the start of a successful test to effective extubation was significantly lower in the TIE group than in the T-piece group, 15 (10 to 24) vs 55 (40 to 75) min, P<0.001. In the Kaplan-Meier analysis, no significant differences were found in successful weaning (79.5 vs 82.5%, P=0.268) or survival rate (62.9 vs 53.8%, P=0.210) between the TIE and T-piece groups at the 30th day. In this preliminary study, the TIE index was not inferior to the T-piece trial as a decision-making tool for extubation and allowed a reduction in the decision time.

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In this work, we have studied the Ising model with one- and two-spin flip competing dynamics on a two-dimensional additive small-world network (A-SWN). The system model consists of an L×L square lattice where each site of the lattice is occupied by a spin variable that interacts with the nearest-neighbor spins and it has a certain probability p of being additionally connected at random to one of its farther neighbors. The dynamics present in the system can be defined by the probability q of being in contact with a heat bath at a given temperature T and, at the same time, with a probability of (1-q) the system is subjected to an external flux of energy into the system. The contact with the heat bath is simulated by one-spin flip according to the Metropolis prescription, while the input of energy is mimicked by the two-spin flip process, involving a simultaneous flipping of a pair of neighboring spins. We have employed Monte Carlo simulations to obtain the thermodynamic quantities of the system, such as the total m_{L}^{F} and staggered m_{L}^{AF} magnetizations per spin, the susceptibility χ_{L}, and the reduced fourth-order Binder cumulant U_{L}. We have built the phase diagram for the stationary states of the model in the plane T versus q, showing the existence of two continuous transition lines for each value of p: one line between the ferromagnetic F and paramagnetic P phases and the other line between the P and antiferromagnetic AF phases. Therefore, we have shown that the phase diagram topology changes when p increases. Using the finite-size scaling analysis, we also obtained the critical exponents for the system, where, varying the parameter p, we have observed a different universality class from the Ising model in the regular square lattice to the A-SWN.

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We describe two new species of monogenean parasites of the genus Gyrodactylus von Nordmann, 1832 infecting Neotropical catfishes (Siluriformes) in southern Mexico: Gyrodactylus chulini n. sp. from 'chulín', Rhamdia laticauda collected in Oaxaca; and Gyrodactylus juili n. sp. from 'juil', Rhamdia guatemalensis from Veracruz. Morphologically, both new taxa are similar to Gyrodactylus spp. infecting catfishes (Siluriformes) in South America. Sequences of the internal transcribed spacers (ITS1-5.8S-ITS2 rDNA), the D2+D3 domains of the large ribosomal subunit (28S rDNA) and the cytochrome oxidase II (COII) gene were obtained from multiple parasite specimens and analysed using Bayesian inference. Phylogenetic hypotheses using ITS rDNA and COII genes, recovered two new Gyrodactylus species from Rhamdia spp.: G. chulini n. sp.; and Gyrodactylus juili n. sp., which are sister species to Gyrodactylus lilianae, a parasite of Rhamdia quelen in Brazil, and show strong affinity to other gyrodactytlids infecting Neotropical catfishes. This suggests that these new taxa, the first gyrodactylids described from Rhamdia spp. in Mexico, co-migrated to Tropical Middle America with their Neotropical catfish hosts, after the emergence of the Isthmus of Panama.

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The "timed inspiratory effort" (TIE) index, a new predictor of weaning outcome, normalizes the maximal inspiratory pressure with the time required to reach this value up to 60 s, incorporating the time domain into the assessment of inspiratory muscle function. The objective of this study was to determine whether the TIE predicts successful extubation at a similar rate as the T-piece trial with less time required. A non-inferiority randomized controlled trial was performed with ICU subjects eligible for weaning. The participants were allocated to the TIE or the T-piece groups. The primary outcome was successful weaning, and the main secondary outcome was ICU mortality. Eighty participants of each group were included in the final analysis. Time from the start of a successful test to effective extubation was significantly lower in the TIE group than in the T-piece group, 15 (10 to 24) vs 55 (40 to 75) min, P<0.001. In the Kaplan-Meier analysis, no significant differences were found in successful weaning (79.5 vs 82.5%, P=0.268) or survival rate (62.9 vs 53.8%, P=0.210) between the TIE and T-piece groups at the 30th day. In this preliminary study, the TIE index was not inferior to the T-piece trial as a decision-making tool for extubation and allowed a reduction in the decision time.

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BACKGROUND: There is increasing interest in studying psychotic symptoms in non-clinical populations, with the Community Assessment of Psychic Experiences-Positive scale (CAPE-P15) being one of the self-screening questionnaires used most commonly for this purpose. Further research is needed to evaluate the ability of the scale to accurately identify and classify positive psychotic experiences (PE) in the general population. AIM: To provide psychometric evidence about the accuracy of the CAPE-P15 for detecting PE in a sample of Chilean adolescents from the general population and classifying them according to their PE severity levels. METHOD: We administered the CAPE-P15 to a general sample of 1594 students aged 12 to 19. Based on Item Response Theory (IRT), we tested the accuracy of the instrument using two main parameters: difficulty and discrimination power of the 15 items. RESULTS: We found that the scale provides very accurate information about PE, particularly for high PE levels. The items with the highest capability to determine the presence of the latent trait were those assessing perceptual anomalies (auditory and visual hallucinations), bizarre experiences (a double has taken the place of others; being controlled by external forces), and persecutory ideation (conspiracy against me). CONCLUSIONS: The CAPE-P15 is an accurate and suitable tool to screen PE and to accurately classify and differentiate PE levels in adolescents from the general population. Further research is needed to better understand how maladaptive psychological mechanisms influence relationships between PE and suicidal ideation (SI) in the general population.

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La presencia de manifestaciones neuropsiquiátricas en pacientes reumatológicos trae consigo un gran desafío diagnóstico que exige una mirada amplia, desde las bases de la medicina interna, a fin de poder orientar un estudio adecuado y el tratamiento oportuno. Junto con ello, el permanente diálogo e intercambio de miradas clínicas con otras especialidades permite tener un enfoque multidisciplinario que enriquece el abordaje de estas presentaciones complejas.

The presence of neuropsychiatric manifestations in rheumatological patients brings with it a great diagnostic challenge that requires a broad view, from the foundations of internal medicine, in order to guide the appropriate study and timely treatment of these patients. Along with this, the permanent dialogue and exchange of clinical views with other specialties allows for a multidisciplinary approach that enriches the approach to these complex presentations.

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Given the importance of the Golden kingklip (Genypterus blacodes) as an alternative to the production of salmonid species for worldwide diversification of aquaculture this study researched the morpho-histology of the digestive canal, providing a uniform nomenclature and basic information to support their nutritional management in captive conditions. The objective was to describe the normal morphology of the digestive canal. Twelve wild specimens were collected and dissected. Samples of the esophagus, stomach, liver, pyloric blind and intestines were obtained. An anatomical and histological description was performed. The digestive canal presented a short tubular esophagus, a slightly dilated, J-shaped stomach and thick walls. The stomach had a cardiac region that ended in a pyloric sphincter from which the intestine of thin walls. The intestine presented an anterior, middle and posterior segment. The anterior region of the first segment of the middle intestine presented 4-5 pairs of pyloric cecum. The middle intestine represented approximately 30 % of the total length of the digestive canal, with a smaller diameter compared to the first segment. The posterior intestine was separated from the middle intestine by a thick and powerful sphincter. The liver was large and elongated, and located in the peritoneal cavity located to the left plane and ventral to the swim bladder. The gallbladder was located lateral to the hepatic anterior wolf. The bile duct led to the duodenal region of the anterior intestine. Ventrally, the rectum ended in the anus, located in front of the anal fin. In general, the histological structures were variable according to the segment studied, a mucous tunic was recognized that presented a simple columnar epithelium, a lamina propria composed of loose connective tissue, a muscular layer of the mucosa composed of smooth muscle tissue and a submucosal layer composed of loose connective tissue, a circular and longitudinal stratum of muscular tunic, which had striated musculature and an adventitial tunic composed of a simple squamous epithelium. In conclusion, Golden kingklip (Genypterus blacodes) presents a digestive system typical of a carnivorous benthic fish adapted to feed on fish and crustaceans.

Dada la importancia del Congrio colorado (Genypterus blacodes) como alternativa a la producción de especies salmonídeas para la diversificación mundial de la acuicultura, el objetivo del presente estudio es describir la morfología normal del canal digestivo de esta especie, proporcionando una nomenclatura uniforme e información básica para apoyar su manejo nutricional en condiciones de cautiverio. Doce especímenes silvestres fueron colectados y disecados. Se obtuvo muestras del esófago, estómago, hígado, ciego pilórico e intestinos. Se realizó una descripción anatómica e histológica. El canal digestivo presentó un esófago tubular corto, un estómago ligeramente dilatado, con forma de J y paredes gruesas. El estómago presentaba una región cardíaca que terminaba en un esfínter pilórico desde el cual el intestino de paredes delgadas. El intestino presentaba un segmento anterior, medio y posterior. La región anterior del primer segmento del intestino medio presentó 4-5 pares de ciegos pilóricos. El intestino medio representó aproximadamente el 30 % de la longitud total del canal digestivo, con un diámetro menor en comparación con el primer segmento. El intestino posterior estaba separado del intestino medio por un esfínter grueso y poderoso. El hígado era grande y alargado, y ubicado en la cavidad peritoneal ubicado al plano izquierdo y ventral a la vejiga natatoria. La vesícula biliar se ubicó lateral al lobo anterior hepático. El ducto biliar desembocó en la región duodenal del intestino anterior. Ventralmente, el recto terminó en el ano, ubicado frente a la aleta anal. En general, las estructuras histológicas fueron variables según el segmento estudiado, se reconoció una túnica mucosa que presentaba un epitelio columnar simple, una lámina propia de la mucosa compuesta por tejido conectivo laxo, una capa muscular de la mucosa compuesta por músculo liso tejido y una capa submucosa compuesta de tejido conectivo laxo, un estrato circular y longitudinal de túnica muscular, que tenía musculatura estriada y una túnica adventicia compuesta por un epitelio plano simple. En conclusión, Congrio colorado (Genypterus blacodes) presenta un sistema digestivo típico de un pez bentónico carnívoro adaptado para alimentarse de peces y crustáceos.

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INTRODUCTION: The Early Feeding Skills (EFS) scale assessed the neonate's behavior before, during, and after the feeding process. OBJECTIVES: To determine the face and content validity, and to evaluate with this scale the feeding process in premature newborns comparing with relevant variables. PATIENTS AND METHOD: Premature newborns were evaluated; they were between 34 to 36 weeks of corrected age, without neurological damage or craniofacial malformations. Cross-sectional descriptive study. The data were obtained through the EFS scale, version corrected by face and content validation. The study variables were gender, breastfeeding achievement, and feeding skills during the feeding process, evaluated by two observers. Dispersion measures were analyzed, and the Fisher test was used at 5% significance, establishing the association of the obtained results with the variables. RESULTS: 5 domains were evaluated: (1) Ability to stay focused on food, in which 75.3% have a poor performance level, and 28.6% equitable, with significant differences in the sex variable. (2) Ability to organize motor- oral functioning presents 10.5% deficient, 68.8% equitable, and 20.6% good. (3) Ability to coordinate swallowing 95.2% presents an equitable performance. (4) Ability to maintain physiological stability 96.7% was equitable; and (5) Evaluation of oral food tolerance presents 41.6% of poor performance. CONCLUSION: The EFS scale is a tool that provides relevant information to describe the oral feeding process in premature infants, allowing to identify the areas of greatest difficulty that require profes sional treatment, however, this tool is not enough by itself to carry a comprehensive evaluation of the newborn feeding process.

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INTRODUCCIÓN: La escala Early Feeding Skills (EFS) evalúa la conducta del neonato antes, durante y posterior al proceso de alimentación. OBJETIVOS: Determinar la validez de fachada, de contenido y evaluar con dicha escala el proceso de alimentación en los recién nacidos prematuros comparando con variables relevantes. PPACIENTES Y MÉTODO: Se evaluaron prematuros de 34 a 36 semanas de edad corregida sin daño neurológico o malformaciones craneofaciales. Diseño de tipo descriptivo de corte transversal. Los datos fueron obtenidos mediante escala EFS, versión corregida mediante validación de fachada y contenido. Las variables de estudio fueron género, logro de alimentación por pecho, y habilidades de alimentación durante el proceso de alimentación, evaluadas por 2 observadoras Se analizaron medidas de dispersión y se aplicó prueba Fisher al 5% de significancia, estableciendo la asociación de los resultados obtenidos con las variables. RESULTADOS: Se evaluaron 5 dominios: (1) Capacidad de mantenerse enfocado en la alimentación, en que el 75,3% posee un nivel desempeño deficiente y el 28,6% equitativo existiendo diferencias significativas con la variable sexo. (2) Capacidad de organizar el funcionamiento motor - oral tiene un 10,5% deficiente, un 68,8% equitativo y un 20,6% bueno. (3) Capacidad de coordinar la deglución el 95,2% presenta un rendimiento equitativo. (4) Capacidad de mantener la estabilidad fisiológica el 96,7% fue equitativo y en (5) Evaluación de la tolerancia alimentaria oral tiene un desempeño deficiente del 41,6%. CONCLUSIÓN: La escala EFS es una herra mienta que aporta información relevante para describir el proceso de alimentación oral en lactantes prematuros, permitiendo identificar las áreas de mayor dificultad que requieren tratamiento profe sional, sin embargo, esta herramienta no es suficiente por sí sola para llevar a cabo una evaluación integral del proceso de alimentación del neonato.

INTRODUCTION: The Early Feeding Skills (EFS) scale assessed the neonate's behavior before, during, and after the feeding process. OBJECTIVES: To determine the face and content validity, and to evaluate with this scale the feeding process in premature newborns comparing with relevant variables. PATIENTS AND METHOD: Premature newborns were evaluated; they were between 34 to 36 weeks of corrected age, without neurological damage or craniofacial malformations. Cross-sectional descriptive study. The data were obtained through the EFS scale, version corrected by face and content validation. The study variables were gender, breastfeeding achievement, and feeding skills during the feeding process, evaluated by two observers. Dispersion measures were analyzed, and the Fisher test was used at 5% significance, establishing the association of the obtained results with the variables. RESULTS: 5 domains were evaluated: (1) Ability to stay focused on food, in which 75.3% have a poor performance level, and 28.6% equitable, with significant differences in the sex variable. (2) Ability to organize motor- oral functioning presents 10.5% deficient, 68.8% equitable, and 20.6% good. (3) Ability to coordinate swallowing 95.2% presents an equitable performance. (4) Ability to maintain physiological stability 96.7% was equitable; and (5) Evaluation of oral food tolerance presents 41.6% of poor performance. CONCLUSION: The EFS scale is a tool that provides relevant information to describe the oral feeding process in premature infants, allowing to identify the areas of greatest difficulty that require profes sional treatment, however, this tool is not enough by itself to carry a comprehensive evaluation of the newborn feeding process.

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