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The influence of trifluoromethanesulfonic (TFSA) superacid on conditions of the synthesis of polybenzimidazoles, such as OPBI and CF3PBI, was studied. It was shown that the polycondensations proceeded smoother and at lower temperatures in the presence of the TFSA in Eaton's Reagent and that polymers of high molecular weights, and readily soluble in organic solvents, were obtained. The effect was more pronounced for CF3PBI, where the low reactivity monomer, 4,4' (hexafluoroisoproylidene)bis (benzoic acid), was used. CF3PBI was obtained at a moderate temperature of 140 °C with no gel fraction and exhibited an inherent viscosity twice higher than the one obtained by the traditional method. In fact, the addition of TFSA allows the obtention of soluble N-phenyl substituted CF3PBI by direct synthesis, which had not been obtained otherwise. Thus, the use of TFSA is a good media for the synthesis of N-substituted PBIs under relatively mild conditions.
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Background: Acute kidney injury (AKI) is associated with poor outcomes in patients infected with SARS-CoV-2. Sepsis, direct injury to kidney cells by the virus, and severe systemic inflammation are mechanisms implicated in its development. We investigated the association between inflammatory markers (C-reactive protein, procalcitonin, D-dimer, lactate dehydrogenase, and ferritin) in patients infected with SARS-CoV-2 and the development of AKI. Methods: A prospective cohort study performed at the Civil Hospital (Dr. Juan I. Menchaca) Guadalajara, Mexico, included patients aged >18 years with a diagnosis of SARS-CoV-2 pneumonia confirmed by RT-PCR and who did or did not present with AKI (KDIGO) while hospitalized. Biomarkers of inflammation were recorded, and kidney function was estimated using the CKD-EPI formula. Results: 291 patients were included (68% males; average age, 57 years). The incidence of AKI was 40.5% (118 patients); 21% developed stage 1 AKI, 6% developed stage 2 AKI, and 14% developed stage 3 AKI. The development of AKI was associated with higher phosphate (p = 0.002) (RR 1.39, CI 95% 1.13-1.72), high procalcitonin levels at hospital admission (p = 0.005) (RR 2.09, CI 95% 1.26-3.50), and high APACHE scores (p = 0.011) (RR 2.0, CI 95% 1.17-3.40). The survival analysis free of AKI according to procalcitonin levels and APACHE scores demonstrated a lower survival in patients with procalcitonin >0.5 ng/ml (p = 0.001) and APACHE >15 points (p = 0.004). Conclusions: Phosphate, high procalcitonin levels, and APACHE levels >15 were predictors of AKI development in patients hospitalized with COVID-19.
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Lesión Renal Aguda , COVID-19 , Sepsis , Masculino , Humanos , Persona de Mediana Edad , Femenino , APACHE , SARS-CoV-2 , Polipéptido alfa Relacionado con Calcitonina , Estudios Prospectivos , Proteína C-Reactiva , COVID-19/complicaciones , COVID-19/diagnóstico , Estudios Retrospectivos , Lesión Renal Aguda/diagnóstico , Biomarcadores , Ferritinas , Fosfatos , Lactato Deshidrogenasas , Factores de RiesgoRESUMEN
Neurons have limited intracellular energy stores but experience acute and unpredictable increases in energy demand. To better understand how these cells repeatedly transit from a resting to active state without undergoing metabolic stress, we monitored their early metabolic response to neurotransmission using ion-sensitive probes and FRET sensors in vitro and in vivo. A short theta burst triggered immediate Na+ entry, followed by a delayed stimulation of the Na+/K+ ATPase pump. Unexpectedly, cytosolic ATP and ADP levels were unperturbed across a wide range of physiological workloads, revealing strict flux coupling between the Na+ pump and mitochondria. Metabolic flux measurements revealed a "priming" phase of mitochondrial energization by pyruvate, whereas glucose consumption coincided with delayed Na+ pump stimulation. Experiments revealed that the Na+ pump plays a permissive role for mitochondrial ATP production and glycolysis. We conclude that neuronal energy homeostasis is not mediated by adenine nucleotides or by Ca2+, but by a mechanism commanded by the Na+ pump.
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Adenosina Trifosfato/metabolismo , Astrocitos/metabolismo , Mitocondrias/metabolismo , Neuronas/metabolismo , ATPasa Intercambiadora de Sodio-Potasio/metabolismo , Animales , Astrocitos/citología , Metabolismo Energético , Glucosa/metabolismo , Glucólisis , Homeostasis , Ratones Endogámicos C57BL , Neuronas/citologíaRESUMEN
The study aimed to assess the pharmacokinetics of a new, modified-release metoclopramide tablet, and compare it to an immediate-release tablet. A single and multiple-dose, randomized, open-label, parallel, pharmacokinetic study was conducted. Investigational products were administered to 26 healthy Hispanic Mexican male volunteers for two consecutive days: either one 30 mg modified-release tablet every 24 h, or one 10 mg immediate-release tablet every 8 h. Blood samples were collected after the first and last doses of metoclopramide. Plasma metoclopramide concentrations were determined by high-performance liquid chromatography. Safety and tolerability were assessed through vital signs measurements, clinical evaluations, and spontaneous reports from study subjects. All 26 subjects were included in the analyses [mean (SD) age: 27 (8) years, range 18-50; BMI: 23.65 (2.22) kg/m², range 18.01-27.47)]. Peak plasmatic concentrations were not statistically different with both formulations, but occurred significantly later (p < 0.05) with the modified-release form [tmax: 3.15 (1.28) vs. 0.85 (0.32) h and tmax-ss: 2.92 (1.19) vs. 1.04 (0.43) h]. There was no difference noted in the average plasma concentrations [Cavgτ: 23.90 (7.90) vs. 20.64 (7.43) ng/mL after the first dose; and Cavg-ss: 31.14 (9.64) vs. 35.59 (12.29) ng/mL after the last dose, (p > 0.05)]. One adverse event was reported in the test group (diarrhea), and one in the reference group (headache). This study suggests that the 30 mg modified-release metoclopramide tablets show features compatible with slow-release formulations when compared to immediate-release tablets, and is suitable for once-a-day administration.
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Antieméticos/farmacocinética , Metoclopramida/farmacocinética , Adolescente , Adulto , Química Farmacéutica , Esquema de Medicación , Humanos , Masculino , Metoclopramida/administración & dosificación , Metoclopramida/efectos adversos , Persona de Mediana Edad , ComprimidosRESUMEN
BACKGROUND: Metoclopramide is a prokinetic and antiemetic agent. OBJECTIVE: The goal of this study was to assess the pharmacokinetics of a new, modified-release metoclopramide tablet and compare it with an immediate-release tablet to obtain marketing approval from the Mexican regulatory agency. METHODS: This was a single-center, randomized, open-label, parallel-group, single- and multiple-dose, pharmacokinetic study. Investigational products were administered to healthy Mexican male volunteers for 3 consecutive days: one 15-mg modified-release tablet every 12 hours or one 10-mg immediate-release tablet every 8 hours. Multiple blood samples were collected after the first and last doses of metoclopramide over a 24-hour period. Plasma metoclopramide concentrations were determined by using a validated HPLC method. Safety and tolerability were assessed by measurement of vital signs, clinical evaluations, and spontaneous reports from study subjects. RESULTS: All 26 subjects were included in the analyses (mean [SD] age: 25 [6] years [range, 18-40 years]; body mass index, 23.44 [2.31] kg/m(2) [range, 18.26-27.49 kg/m2]). Peak plasma concentrations were lower (C(max), 33.13 [7.25] vs 46.04 [17.27] ng/mL after the first dose [P < 0.05]; C(max,ss), 48.60 [8.52] vs 75.23 [21.27] ng/mL after the last dose [P < 0.05]) and occurred later (P < 0.05) with the modified-release formulation. In terms of average plasma concentrations (C(avgτ), 20.98 [3.94] vs 23.38 [7.35] ng/mL after the first dose; C(avg,ss), 22.20 [5.64] vs 23.02 [7.77] ng/mL after the last dose), differences did not reach the level of statistical significance (P > 0.05). Four adverse events were reported in the test group (abdominal distention [n = 2], epigastric pain [n = 1], and somnolence [n = 1]), and 3 were reported in the reference group (epigastric pain [n = 1], diarrhea [n = 1], and hiccups [n = 1]). CONCLUSIONS: This study in a sample of selected healthy Mexican male volunteers suggests that the metoclopramide15-mg modified-release tablets have features compatible with the slow-release formulation (lower C(max) and longer T(max)) compared with immediate-release tablets.
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Antieméticos/farmacocinética , Formas de Dosificación , Metoclopramida/farmacocinética , Comprimidos , Adulto , Disponibilidad Biológica , Humanos , Masculino , Valores de ReferenciaRESUMEN
Antecedentes. El estudio de los estilos cognitivos se ha desarrollado desde la primera mitad del siglo XX. A pesar de esto, la mayoría de las investigaciones se han realizado con estudiantes de educación básica y media, encontrándose pocos estudios de educación superior y especialmente en estudiantes de la carrera de Nutrición y dietética. Objetivos. Determinar los estilos cognitivos de aprendizaje predominantes entre estudiantes de la carrera de Nutrición y dietética de la Universidad Nacional de Colombia, para identificar su correspondencia con las habilidades cognitivas explícitas en el programa académico. Materiales y métodos. Para determinar el estilo cognitivo en la dimensión de independencia-dependencia de campo, se utilizó la prueba de figuras enmascaradas. Además, se aplicó una encuesta sociocultural y cuestionarios de auto reporte para identificar preferencias de aprendizaje y estudio. Resultados. El 40,4% de los estudiantes se caracterizó por ser independientes de campo y el 33,6% dependientes de campo; los demás tuvieron un estilo cognitivo intermedio. Los estudiantes muy independientes de campo manifestaron preferir realizar actividades solamente de tipo académico. Los independientes de campo refirieron que casi siempre preferían realizar actividades artísticas y deportivas, ordenaban su sitio de trabajo antes de estudiar, casi nunca hacían resúmenes y consideraban que las clases magistrales no facilitaban el aprendizaje. Los dependientes de campo preferían escuchar música, chatear y ver televisión mientras estudiaban; se destaca que el 74% manifestó que casi siempre preparaban sus evaluaciones teniendo en cuenta sólo lo sugerido por el profesor. Conclusiones. En el estudio predominó el estilo cognitivo de independencia de campo. Ser reflexivo, analítico, crítico y creativo, habilidades explicitas en el perfil del estudiante de nutrición, se encuentran más desarrolladas por estudiantes en quienes predomina este estilo, mientras que, otras como: trabajo en equipo y sensibilidad social son predominantes en individuos dependientes de campo.
Background. Cognitive styles have been studied since the first half of the 20th century. In spite of this, most research has been carried out on elementary- and middleschool students; few studies have been concerned with higher education students, especially regarding students studying nutrition and dietetics. Objectives. Determining predominant cognitive learning styles amongst students studying nutrition and dietetics in the Universidad Nacional de Colombia so as to identify how they are may be matched with explicit cognitive skills in such academic programme. Materials and methods. The masked figures test was used for determining cognitive style in the field independence-dependence dimension. A sociocultural survey was conducted and self-reporting questionnaires were used for identifying learning and study preferences. Results. 40.4% of the students were characterized as being field-independent and 33.6% field-dependent; the rest had an intermediate cognitive style. Very fieldindependent students stated that they only preferred academic activities. Field-independent ones nearly always referred to preferring artistic and sporting-type activities, organizing their workplaces before starting to study, almost never making summaries and considering that traditional taught classes did not facilitate learning. Fielddependent students preferred listening to music, chatting on-line and watching television whilst they were studying; it is worth pointing out that 74% stated that they almost always prepared their evaluations/tests bearing only that in mind which had been suggested by the teacher. Conclusions. Field-independent cognitive learning style predominated amongst students involved in the study. Being reflective, analytical, critical and creative (explicit skills in a nutrition student's profile) were more developed in students in whom this type of style predominated, whilst others, such as working as part of a team and social sensitivity, predominated in fielddependent individuals.
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En la presente investigacion se extrae, purifica y caracteriza una proteina almacenadora de hierro, la ferritina a partir de un homogenado de higado de vaca. Inicialmente la purificacion por desnaturacion termal y precipitacion con sulfato de amonio y posteriormente por metodos cromatograficos. En la segunda parte del estudio, se realiza un tratmiento comparativo en niños con anemia ferropenica con sulfato ferroso y con ferritina. El analisis estadistico del estudio refleja claramente respuesta significativa en el aumento de los niveles sericos de hierro en grupo de niños tratados con ferritina la proteina obtenida puede ser utilizada como fuente nacional...
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Anemia Ferropénica , Bioquímica , Ferritinas , Ferritinas/biosíntesis , Ferritinas/fisiología , Ferritinas/ultraestructuraRESUMEN
La situación económica del país es un factor preponderante a las condiciones defificientes del saneamiento básico, el cual influye sobre nuestra salud. Se hace referencia del 80 por ciento de hogares bolivianos pobres que viven en condiciones de saneamiento deficiente, por esta causa están predispuestas a contraer cualquier tipo de enfermedad. Por esta razón deficiente las poblaciones de las areas rurales y periurbanas no tienen información adecuada sobre la prevención de enfermedades. Uno de los componentes de saneamiento básico es el agua, elemento indispensable para la subsistencia del hombre, a través del cual también se obtienen enfermedades gastrointestinales, como hepatitis, gastroenteritis, shigollosis, cólera, salmonellosis, las cuales estarán presentes por el mal uso y tratamiento de agua. Es también indispensable para la higiene personal, protegiendo nuestra salud, dentro de la higiene se hace mención la práctica del lavado de manos, lo cual es significativo, porque a través de ésta contrae enfermedades entéricas con una autocontaminación de ano-boca como resultado de la mala higiene de las manos
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Asepsia , Desinfección de las ManosRESUMEN
La situación económica del país es un factor preponderante a las condiciones defificientes del saneamiento básico, el cual influye sobre nuestra salud. Se hace referencia del 80 por ciento de hogares bolivianos pobres que viven en condiciones de saneamiento deficiente, por esta causa están predispuestas a contraer cualquier tipo de enfermedad. Por esta razón deficiente las poblaciones de las areas rurales y periurbanas no tienen información adecuada sobre la prevención de enfermedades. Uno de los componentes de saneamiento básico es el agua, elemento indispensable para la subsistencia del hombre, a través del cual también se obtienen enfermedades gastrointestinales, como hepatitis, gastroenteritis, shigollosis, cólera, salmonellosis, las cuales estarán presentes por el mal uso y tratamiento de agua. Es también indispensable para la higiene personal, protegiendo nuestra salud, dentro de la higiene se hace mención la práctica del lavado de manos, lo cual es significativo, porque a través de ésta contrae enfermedades entéricas con una autocontaminación de ano-boca como resultado de la mala higiene de las manos
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Asepsia , Desinfección de las ManosRESUMEN
Actualmente se considera a la embarazada como una enferma más dentro del Hospital o Sanatorio y se tiende a tomar una actitud intervencionista respecto a ella, dejando de lado todo ,o natural y fisiológico del embarazo, trabajo de parto y parto. Esta actitud, en gran parte, se debe al avance de la técnología médica, que, si bien en algunos casos es muy útil, en el 85 por ciento de los embarazos que son normales, no se justifica como "intervención"