127 research outputs found
A Potential Route to Reduce Ischemia/Reperfusion Injury in Organ Preservation
The pathophysiological process of ischemia and reperfusion injury (IRI), an inevitable step in organ transplantation, causes important biochemical and structural changes that can result in serious organ damage. IRI is relevant for early graft dysfunction and graft survival. Today, in a global context of organ shortages, most organs come from extended criteria donors (ECDs), which are more sensitive to IRI. The main objective of organ preservation solutions is to protect against IRI through the application of specific, nonphysiological components, under conditions of no blood or oxygen, and then under conditions of metabolic reduction by hypothermia. The composition of hypothermic solutions includes osmotic and oncotic buffering components, and they are intracellular (rich in potassium) or extracellular (rich in sodium). However, above all, they all contain the same type of components intended to protect against IRI, such as glutathione, adenosine and allopurinol. These components have not changed for more than 30 years, even though our knowledge of IRI, and much of the relevant literature, questions their stability or efficacy. In addition, several pharmacological molecules have been the subjects of preclinical studies to optimize this protection. Among them, trimetazidine, tacrolimus and carvedilol have shown the most benefits. In fact, these drugs are already in clinical use, and it is a question of repositioning them for this novel use, without additional risk. This new strategy of including them would allow us to shift from cold storage solutions to cold preservation solutions including multitarget pharmacological components, offering protection against IRI and thus protecting today's more vulnerable organs
Stereotactic MR-guided online adaptive radiation therapy (SMART) for ultracentral thorax malignancies: Results of a phase 1 trial
Endoparasitos de Myrmecophaga tridactyla Y Tamandua tetradactyla (pilosa: vermilingua) silvestres en Casanare, Colombia
Endoparasites of 11 giant anteaters (Myrmecophaga tridactyla) and two southern tamanduas (Tamandua tetradactyla) present in livestock areas of the municipality of Pore, Casanare, Colombia, were determined. Blood and feces of giant anteaters anesthetized on field were collected while southern tamandua’s feces samples were collected from individuals killed on roads of the area. Feces were analyzed by sedimentation and flotation techniques and hemoparasites were determined by thick smear technique. Seven M. tridactyla (63.6%) and both T. tetradactyla (100%) were positive for gastrointestinal parasites. The prevalence of each parasite in giant anteaters was: Coccidia sp (28%), Blastocistis hominis (28%), Entomoeba dispar (14.28%), Giardia lamblia (14.28%), Isospora sp. (14.28%), Strongyloides sp. (14.28%), Ascaris lumbricoides (14.28%) and Chilomastix mesnili (14.28%). As for southern tamanduas, the most prevalent parasite was Coccidia (100%), while Trichostrongylus sp., and Taenia sp., had a prevalence of 50%. The monoxenas parasitic forms were predominant on those with multiple hosts cycles, probably for the direct consumption of land and/or water contaminated with fecal material. This is the first report of parasites occurrence in wild Vermilingua in Colombia. Although the sample sizes are not significant, and there is not enough evidence to say that these parasitic infestations may be severely affecting the sampled individuals, this information may be useful for reintroduction programs and management of these species Se determinaron los endoparásitos de 11 osos hormigueros gigantes (Myrmecophaga tridactyla) y dos osos meleros (Tamandua tetradactyla) presentes en zonas ganaderas del municipio de Pore, Casanare, Colombia. Serecolectaronmuestras desangrey heces dehormiguerosgigantesanestesiados encampo, mientras que las muestras de heces de osos meleros fueron recolectadas de individuos atropellados en la zona. Se analizaron las heces mediante técnicas de sedimentación y flotación, y se determinaron hemoparásitos mediante la técnica de gota gruesa. Siete M. tridactyla (63,6%) y ambos T. tetradactyla (100%) seencontraronpositivosaalgunaespeciedeparásitogastrointestinal. La prevalenciade cadauno de los parásitos identificados en hormigueros gigantes fue: Coccidia sp (28%), Blastocistis hominis (28%), Entomoebadispar (14,28%), Giardialamblia (14,28%), Isospora sp.(14,28%), Strongyloides sp.(14,28%), Ascarislumbricoides (14,28%) y Chilomastixmesnili (14,28%). Encuantoalosososmeleros, la Coccidia fue el parásito más prevalente (100%), mientras que Trichostrongylus sp., y Taenia sp., presentaron una prevalencia del 50%. Las formas parásitas monoxenas fueron predominantes sobre aquellas que tienen ciclos de varios huéspedes, probablemente por el consumo directo de tierra y/o agua contaminada con material fecal. Se presenta el primer reporte de parásitos en Vermilingua silvestres en Colombia. Si bien los tamaños de muestra no son significativos, y no se cuenta con evidencia suficiente para afirmar que estas infestaciones parasitarias puedan estar afectando de manera severa a los individuos muestreados, esta información puede ser de utilidad para programas de reintroducción y manejo de estas especie
Nivel de proteína C reactiva en pacientes con obesidad mórbida antes y después de cirugía bariátrica
ResumenAntecedentesLa obesidad humana se asocia a un estado proinflamatorio reflejado en elevación de marcadores como la proteína C reactiva (PCR).ObjetivosEstablecer los valores de PCR basales y a 6 meses de la cirugía bariátrica, así como los cambios en peso, índice de masa corporal (IMC), leucocitos y glucemia.Materiales y métodosSe realizó un estudio observacional, analítico, retrospectivo, longitudinal y abierto. Se midieron los valores de PCR sérica y su relación con el peso, IMC, leucocitos y glucemia de manera basal y 6 meses posteriores a cirugía bariátrica en 36 adultos con obesidad mórbida.ResultadosLa media ± desviación estándar de la PCR pre y posoperatorio (mg/l) fue 1.15±0.86 y 0.34±0.28, respectivamente, con p<0.0001; peso (kg) 112.10±22.91 y 84.82±17.11, p=0,0443; IMC (kg/m2) 42.48±5.97 y 32.2±4.79, p=0.0988; glucosa (mg/dl) 100.58±17.82 y 87.11±8.49, p<0.0001, y leucocitos (× 103/mm3) 8.62±1.69 y 6.99±1.56, p=0.3192.La PCR basal solo correlacionó con el peso e IMC (p=0.047 y p=0.027, respectivamente) y no hubo correlación entre la PCR posoperatoria y ninguno de los parámetros evaluados.ConclusionesLa PCR tiene una relación lineal significativa en el preoperatorio con el peso y el IMC. Los pacientes sometidos a cirugía bariátrica presentaron disminución significativa en la PCR, el peso y la glucemia en ayuno a los 6 meses posterior a la cirugía.AbstractBackgroundHuman obesity is associated with a proinflammatory state and an elevated level of mediators, such as C-reactive protein (CRP).ObjectivesTo establish CRP levels as baseline preoperative values and then at 6 months after bariatric surgery, as well as to determine the changes in weight, body mass index (BMI), leukocytes, and glycemia.Materials and methodsAn observational, analytical, retrospective, longitudinal, and open study was conducted. Serum CRP values were measured in 36 adults presenting with morbid obesity, and their baseline relation to weight, BMI, leukocytes, and glycemia was determined; the relation to the same parameters was established again, 6 months after bariatric surgery.ResultsThe mean and standard deviation of preoperative and postoperative CRP (mg/L) was 1.15±0.86 and 0.34±0.28, respectively with p<0.0001; weight (kg) 112.10±22.91 and 84.82±17.11, p=0.0443; BMI (kg/m2) 42.48±5.97 and 32.2±4.79, p=0.0988; glucose (mg/dL) 100.58±17.82 and 87.11±8.49, p<0.0001, and leukocytes (× 103/mm3) 8.62±1.69 and 6.99±1.56, p=0.3192.Baseline CRP only correlated with weight and BMI (p=0.047 and p=0.027 respectively) and there was no correlation between postoperative CRP and the evaluated parameters.ConclusionsPreoperative CRP had a significant lineal relation to weight and body mass index. Patients who underwent bariatric surgery had a significant decrease in CRP, weight, and fasting glucose at 6 months after surgery
Criotolerancia de Semen Equino Congelado con Aditivos en el Diluyente
Extenders have been established as an alternative to compensate the antioxidant deficiencies of stallion semen during freezing. Several research works have aimed to evaluate the effect of various additives with antioxidant properties on the equine sperm cryotolerance; however, in limited occasions this has been linked with the extender total antioxidant capacity (TAC). This research aimed to evaluate the effect of two additives on freezing extender TAC and stallion semen cryotolerance. Semen of five Colombian Creole horses was frozen in an extender under three treatments: T0: control, T1: quercetin 100 μM, T2: phosphates and carbonates (Na2HPO4 0.32 mg/ml + KH2PO4 0.67 mg/ml + K2CO3 0.39 mg/ml). TAC of extender was evaluated by the ABTS test. Post-thaw motility and kinetics, abnormal morphology (AM), and structural (MSI) and functional (HOS) plasma membrane integrity were assessed. The results were analysed using mixed models. TAC values (μmol trolox/l) for T0, T1 and T2 of 10890 ± 210, 14260 ± 410 and 14670 ± 410 were found. The T2 had higher values for most parameters of motility and membrane integrity (p<0.05). It is concluded that the addition of phosphates and carbonates increases the freezing extender TAC and improves stallion semen cryotolerance.Los diluyentes se han constituido como una alternativa para compensar las deficiencias antioxidantes del semen equino durante su congelación. Muchas investigaciones han estado dirigidas a evaluar el efecto de diversos aditivos con propiedades antioxidantes sobre la criotolerancia de los espermatozoides equinos; sin embargo, en limitadas ocasiones se ha relacionado dicha propiedad con la capacidad antioxidante total (CAT) del diluyente. Esta investigación tuvo como objetivo evaluar el efecto de dos aditivos sobre la CAT del diluyente de congelación y la criotolerancia del semen equino. El semen de cinco caballos criollos colombianos se congeló con un diluyente en tres tratamientos: T0: control, T1: quercetina 100 μM, T2: fosfatos y carbonatos (Na2HPO4 0.32 mg/ml + KH2PO4 0.67 mg/ml + K2CO3 0.39 mg/ml). Se evaluó la CAT del diluyente mediante la prueba ABTS. En el semen descongelado se evaluó la movilidad y la cinética, la morfología anormal (MA) y la integridad estructural (IEM) y funcional (HOS) de la membrana plasmática de los espermatozoides. Los resultados se analizaron mediante modelos mixtos. Se hallaron valores de CAT (ìmol trolox/l) para T0, T1 y T2 de 10890 ± 210, 14260 ± 410 y 14670 ± 410, respectivamente. El T2 presentó valores superiores para la mayoría de parámetros de movilidad e integridad de membrana (p<0.05). Se concluye que la adición de fosfatos y carbonatos incrementa la CAT del diluyente de congelación y mejora la criotolerancia del semen equino
Efecto de un proceso de deshidratación con aire forzado en la composición química y nutricional de la mora de castilla (rubus glaucus).
La pérdida y contenido de vitamina C, fenoles totales, capacidad antioxidante y actividad acuosa fueron determinadas para mora deshidratada a tres niveles de temperatura (35, 50 y 65C) y dos tamaños de partícula (mora troceada y mora licuada). Los resultados mostraron una disminución del contenido de la vitamina C a medida que se incrementó la temperatura de deshidratación, presentándose pérdidas superiores al 50% con respecto a la mora fresca. Tendencia similar mostró el contenido de fenoles totales, donde el tratamiento más severo disminuyó su contenido en un 26,7%. Sin embargo, la capacidad antioxidante de la mora no fue afectada severamente por el proceso de deshidratación, siendo constante su valor y equivalente al 50% en promedio respecto al BHA (Butil Hidroxianisol). La actividad acuosa del producto disminuyó a medida que se incrementó la temperatura de deshidratación, presentando valores de 0,43 para 65C y 0,96 para la mora fresca
Capacidad reductora de 15 frutas tropicales
Los antioxidantes son compuestos usados en la industria de alimentos por su capacidad conservadora y se considera que previenen enfermedades. En ésta investigación se estudia la capacidad antioxidante de extractos acuosos por Voltametría Cíclica y el efecto reductor de extractos etanólicos por FRAP (Ferric Reducing Antioxidant Power) de 15 frutas tropicales. Los mejores resultados tanto de capacidad antioxidante como reductora son los de la curuba larga (Passiflora mollisima (HBK) Bailey) con una altura de pico máxima de 38,6 décimas de μA a un potencial de 316,6 mV y 4127,346 ± 108,62 mg Ácido Ascórbico/ 100gr de muestra, respectivamente
Tropheryma whipplei, the Whipple's disease bacillus, induces macrophage apoptosis through the extrinsic pathway
Tropheryma whipplei, the etiological agent of Whipple's disease, is an intracellular bacterium that infects macrophages. We previously showed that infection of macrophages results in M2 polarization associated with induction of apoptosis and interleukin (IL)-16 secretion. In patients with Whipple's disease, circulating levels of apoptotic markers and IL-16 are increased and correlate with the activity of the disease. To gain insight into the understanding of the pathophysiology of this rare disease, we examined the molecular pathways involved in T. whipplei-induced apoptosis of human macrophages. Our data showed that apoptosis induction depended on bacterial viability and inhibition of bacterial protein synthesis reduced the apoptotic program elicited by T. whipplei. Induction of apoptosis was also associated with a massive degradation of both pro- and anti-apoptotic mediators. Caspase-specific inhibition experiments revealed that initiator caspases 8 and 10 were required for apoptosis, in contrast to caspases 2 and 9, in spite of cytochrome-c release from mitochondria. Finally, the effector caspases 3 and 6 were mandatory for apoptosis induction. Collectively, these data suggest that T. whipplei induces apoptosis through the extrinsic pathway and that, beside M2 polarization of macrophages, apoptosis induction contributes to bacterial replication and represents a virulence trait of this intracellular pathogen
Analysis of association of MEF2C, SOST and JAG1 genes with bone mineral density in Mexican-Mestizo postmenopausal women
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