Intra-articular Pressure in the Distal Radioulnar Joint: A Biomechanical Study.

PURPOSE: The aim of the study was to use cadaveric models to assess the effect of loading the forearm muscles in different forearm rotations, with or without disruption to the stabilizing components, on the intra-articular pressure of the distal radioulnar joint (DRUJ). METHODS: Ten forearms with no severe osteoarthritis or injury to the DRUJ stabilizers were used. They were placed in a vertical support, and pressure sensors measured pressure within the DRUJ in 5 forearm rotations (neutral, pronation, supination, extension, and flexion) under the following 6 conditions: 1) no loading; 2) loading (at 1/5 of the load per cross-sectional area) with no disruption; 3) loading with disruption of the triangular fibrocartilage complex (TFCC); 4) loading with disruption of the TFCC and ulnar ligaments (ULs); 5) loading with disruption of the TFCC, ULs and interosseous membrane (IM); and 6) loading with disruption of the TFCC, ULs, IM, and pronator quadratus (PQ). RESULTS: Under the no disruption-no load, no disruption-loaded, and disrupted TFCC conditions, the highest intra-articular pressures were recorded in supination. Compared with the no-load condition, pressure was greater in the no disruption-loaded condition with a mean difference (MD) of 1.57 kg/cm2 in a neutral position. In flexion, pressure was greater with a disrupted TFCC (MD, 4.3 kg/cm2). In supination, pressure was only greater with a disrupted TFCC (MD, 3.3 kg/cm2), and pressure decreased in the other disruption conditions. The pressures recorded did not differ from the no disruption-no load condition in pronation or extension. CONCLUSIONS: Pressures within the DRUJ changed with forearm rotations. In the no disruption-no load, no disruption-loaded, and disrupted TFCC conditions, intra-articular pressure was highest in supination. In flexion and supination with load and disruption of stabilizers, intra-articular pressure only increased significantly in the disrupted TFCC condition compared with no load. CLINICAL RELEVANCE: Based on our findings, exercises in supination should be avoided during the first phase of rehabilitation of TFCC injuries given the increased pressure on the DRUJ.

Stress effects on spatial memory retrieval and brain c-Fos expression pattern in adults are modulated by early nicotine exposure.

The cognitive effects of nicotine are linked to persistent modifications in extended neural systems that regulate cognitive and emotional processes, and these changes occur during development. Additionally, acute stress has modulatory effects on cognition that involve broad neural systems and can be influenced by prior environmental challenges. The effects of nicotine and stress may be interconnected, leading to modifications in a network of shared brain substrates. Here, we explored the interaction between nicotine and stress by evaluating the effects of acute stress exposure in spatial memory retrieval for animals pretreated with nicotine during adolescence or adulthood. Adolescent (35 days old) and adult (70 days old) male Wistar rats were treated for 21 days with one daily subcutaneous injection of nicotine 0.14 mg/ml (free base). 30 days after the last injection, rats were trained in the Barnes maze and tested 24 h later, half the rats were tested under regular conditions, and half of them were exposed to 1 h of restraining stress before the retrieval test, and brain samples were collected and c-Fos immunopositive cells were stained. Prolonged nicotine withdrawal or acute stress improved spatial memory retrieval. Acute stress in nicotine pretreated adults impaired spatial memory retrieval. Nicotine exposure during early adulthood resulted in long-lasting brain adaptations that amplified emotional responses to acute stress after prolonged drug withdrawal.

Utilization of Vaccinium meridionale S. pomace as an eco-friendly and functional colorant in Greek-style yogurt.

Greek-style yogurt (GSY) has gained reputation as a healthy food because of its high protein content. Vaccinium meridionale S. is a bilberry with a high content of bioactive phytochemicals, whose vaccinium meridionale pomace (VMP) represents about 20% of the fruit weight. However, this byproduct is normally discarded as waste. In this study, VMP was used as a natural colorant in GSY. Coloring before or after the fermentation process resulted in significant increase in anthocyanins, total phenolics content, antioxidant activity, conjugated linoleic acid, and sensory acceptance. These results indicate that VMP is a potential natural, eco-friendly, and functional colorant to improve the nutritional value of GSY. PRACTICAL APPLICATION: Vaccinium meridionale pomace is a waste product with potential to be utilized as a natural, eco-friendly, and functional colorant to obtain value-added Greek-style yogurt. Besides providing bioactive compounds and natural color, this pomace improves the nutritional value, sensory acceptance, and functional properties of Greek yogurt.

Evaluation of the production of antifungal metabolites against Colletotrichum gloeosporioides in Streptomyces 5.1 by random mutagenesis

Streptomyces 5.1 is a bacterium isolated from rice soils in the south of the Tolima department (Colombia). This microorganism is characterized by its antagonistic activity against rubber tree phytopathogens like Colletotrichum gloeosporioides, the causal agent of leaf anthracnose. The antifungal activity of this Streptomyces isolate has been associated with secondary metabolites production. However, the identity of those metabolites is unknown because its purification and identification have not been possible through classic chemical studies. Therefore, aiming to contribute in the study of the secondary metabolites produced by 5.1 from a molecular approach, this research seeks to identify -preliminarily- the genomic fingerprint changes associated with the production of antifungal secondary metabolites produced by Streptomyces 5.1 through the evaluation of a mutant library of 5.1 obtained by random mutagenesis using controlled ultraviolet light exposure. The antifungal activity of obtained mutants was evaluated using Colletotrichum gloeosporioides (C1) fungus as a biosensor, isolated by the Biotechnology Institute of Universidad Nacional de Colombia. In this way, the library of mutants of 5.1, initially formed by 300 isolations, was classified into two phenotypic groups of interest: enhanced mutants (1 isolate) and null mutants (11 isolates) of secondary metabolites. The genomic changes in both groups were analyzed by obtaining the genomic profile of the isolates using Repetitive Extragenic Palindromic (Rep-PCR). The obtained profiles evidenced the presence of one additional band in the enhanced mutant, and the absence of a specific band in the non-producing mutants, both in comparison with the original strain. These bands are proposed for a future sequencing study which will define their role in the production process of metabolites with antifungal activity in Streptomyces 5.1.(AU)

Evaluation of the production of antifungal metabolites against Colletotrichum gloeosporioides in Streptomyces 5.1 by random mutagenesis

Streptomyces 5.1 is a bacterium isolated from rice soils in the south of the Tolima department (Colombia). This microorganism is characterized by its antagonistic activity against rubber tree phytopathogens like Colletotrichum gloeosporioides, the causal agent of leaf anthracnose. The antifungal activity of this Streptomyces isolate has been associated with secondary metabolites production. However, the identity of those metabolites is unknown because its purification and identification have not been possible through classic chemical studies. Therefore, aiming to contribute in the study of the secondary metabolites produced by 5.1 from a molecular approach, this research seeks to identify -preliminarily- the genomic fingerprint changes associated with the production of antifungal secondary metabolites produced by Streptomyces 5.1 through the evaluation of a mutant library of 5.1 obtained by random mutagenesis using controlled ultraviolet light exposure. The antifungal activity of obtained mutants was evaluated using Colletotrichum gloeosporioides (C1) fungus as a biosensor, isolated by the Biotechnology Institute of Universidad Nacional de Colombia. In this way, the library of mutants of 5.1, initially formed by 300 isolations, was classified into two phenotypic groups of interest: enhanced mutants (1 isolate) and null mutants (11 isolates) of secondary metabolites. The genomic changes in both groups were analyzed by obtaining the genomic profile of the isolates using Repetitive Extragenic Palindromic (Rep-PCR). The obtained profiles evidenced the presence of one additional band in the enhanced mutant, and the absence of a specific band in the non-producing mutants, both in comparison with the original strain. These bands are proposed for a future sequencing study which will define their role in the production process of metabolites with antifungal activity in Streptomyces 5.1.

Acido linoleico conjugado, perfil de ácidos grasos y propiedadesdel proceso en kumis - bebida fermentada consumida en Colombia / Conjugated linoleic acid, fatty acid profile and process properties in kumis - fermented milk consumed in Colombia

In this study, we reported the concentration of conjugated linoleic acid of the main commercial kumis consumed and distributed in Colombia, as well as the concentration of conjugated linoleic acid of anartisanal kumis elaborated with two different types of milk (skim liquid and powder reconstituted). Conjugated linoleic acid (C18:2c9t11) contents, expressed as mg of rumenic acid/g fat, ranged from 7.63± 0.96 to 22.62 ± 3.85. Also, the main fatty acids of kumis samples were identified and quantified. pH value ranged between 3.84 ± 0.02 and 4.28 ± 0.01, and titratable acidity ranged between 0.69 ± 0.01 and0.94 ± 0.02% of lactic acid. Consistence and flux indices presented values between 2.01 ± 0.05 and 7.08± 0.39 (Pa sn) and from 0.43 to 0.26, respectively. These results indicate that kumis is a food product that could be used for supplying important amounts of conjugated linoleic acid in the human diet.

En este estudio reportamos las concentraciones de ácido linoleico conjugado en algunos de los kumiscomerciales de mayor distribución y consumo en Colombia, así como de kumis artesanal elaborado con dos tipos diferentes de leche (líquida semidescremada y leche en polvo reconstituida). Los contenidos de ácido linoleico conjugado (C18:2c9t11), expresadas en mg de ácido ruménico/g grasa, variaron de 7,63 ± 0,96 a 22,62 ± 3,85. Los principales ácidos grasos de las muestras de kumis fueron tambiénidentificados y cuantificados. Los valores de pH y la acidez titulable variaron entre 3,84 ± 0,02 y 4,28 ± 0,01, y entre 0,69 ± 0,01 y 0,94 ± 0,02% ácido láctico, respectivamente. Los índices de consistencia y de flujo presentaron valores entre 2,01 ± 0,05 y 7,08 ± 0,39 (Pa sn), y de 0,43 a 0,26, respectivamente. Estos resultados indican que el kumis es un alimento que podría ser utilizado para aportar cantidades importantes de ácido linoleico conjugado en la dieta humana.

Influencia de las bacterias psicrótrofas en la actividad proteolítica de la leche / Influence of psichrotrophic bacteria proteolytic activity of milk

La refrigeración de la leche reduce el ritmo de multiplicación y actividad de los microorganismos,pero ha generado nuevos problemas relacionados con el crecimiento y la actividad de losmicroorganismos psicrótrofos, que son aquellos que crecen a temperaturas inferiores a 7 °C, independientementede su temperatura óptima. Estos microorganismos producen enzimas termoestablesque degradan algunos componentes de la leche deteriorando su calidad y la de sus derivados,y disminuyendo los rendimientos queseros. Con el fin de evaluar la actividadproteolítica de las bacterias psicrótrofas sobre las caseínas y su relación con la temperatura ytiempo de almacenamiento de la leche, se inocularon diferentes lotes de leche con este tipo debacterias, hasta obtener recuentos de 104 y 105 unidades formadoras de colonia por mililitro(ufc/ml); como control se utilizó leche que no recibió inoculación con recuento de psicrótrofos de103 ufc/ml. Después de almacenar la leche a 4 y 7°C durante tres y seis días, se evaluó la actividadproteolítica sobre las caseínas. Al almacenar leche durante tres días a 4 y 7 °C,nose presentó actividad proteolítica cuando el recuento inicial de psicrótrofos era del orden de 103 ufc/ml, mientrasque cuando dicho recuento fue superior a 104 ufc/ml se observó actividad proteolítica, siendomás intensa a 7 °C que a 4 °C. Con almacenamiento de seis días, solamente la leche conservada a4 °C con recuento inicial de 103 ufc/ml no presentó actividad proteolítica, los demás tratamientosmostraron gran actividad proteolítica sobre la fracción de caseínas aumentando dicha actividad amedida que aumenta el grado de contaminación...

Validación de la pletismografía de impedancia como pruba diagnóstica de la trombosis venosa profunda proximal de miembros inferiores: estudio de concordancia entre venografía y pletismografía

Introducción: La trombosis venosa profunda proximal de miembros inferiores (TVPPMI) es una entidad potencialmente mortal; de la rapidez del diagnóstico y la intervención depende el curso y complicaciones de la enfermedad. El diagnóstico por pletismografía de impedancia facilita el seguimiento y la conducta terapéutica; sin embargo, su sensibilidad y especificidad ha sido cuestionada y se propone el reemplazo por otros métodos no invasivos (doppler venoso). Objetivos: Determinar la sensibilidad y especificidad de la pletismografía de impedancia de miembros inferiores en el diagnóstico de la TVPPMI en pacientes con clínica o con factores de riesgo para esta enfermedad en el Hospital Universitario San Ignacio. Diseño: estudio de concordancia entre la venografía (patrón de oro) y la pletismografía de impedancia (IPG). Pacientes y Métodos: Entre febrero de 1994 y marzo de 1995 ingresaron 62 pacientes con clínica de TVPPMI o con factores de riesgo para la enfermedad al servicio de Medicina Interna o al Departamento del Radiología del Hospital Universitario San Ignacio. Se diligenció una historia clínica haciendo énfasis en los factores de riesgo y en el diagnóstico; se les realizó pletismografía de impedancia de miembros inferiores y posteriormente una venografía. Resultados: Se incluyeron 62 sujetos, de los cuales ocho se excluyen y se analizan un total de 54 pacientes. El 11 por ciento presentaban historia clínica de trombosis venosa profunda y el grupo restante, factores de riesgo para adquirir la enfermedad. La sensibilidad de la IPG en el diagnóstico de TVPPMI del grupo en general fue del 100 por ciento con especificidad de 92 por ciento, con un valor predictivo positico del 33 por ciento. En pacientes con sospecha clínica la sensibilidad fue del 100 por ciento y la especificidad del 90 por ciento; en pacientes sin clínica pero con factores de riesgo no se pudo calcular la sensibilidad y la especificidad fue del 90 por ciento. Conclusión: En pacientes con sospecha clínica de TVPPMI, la IPG tiene alta sensibilidad como método diagnóstico; su valor predictivo positivo en este estudio es bajo por el tamaño de la muestra. Se debe continuar el estudio incluyendo más pacientes con clínica o con alto riesgo de tener TVPPMI.

Ulcera de estresse: visäo atual / Stress ulceration: actual view

Os autores fazem uma breve revisäo sobre úlcera de estresse, relacionando os mecanismos bioquímicos envolvidos com a fisiopatologia e a incidência da doença. Discutem-se, ainda, perspectivas atuais do tratamento e complicaçöes encontradas