Acrylamide bioaccessibility in potato and veggie chips. Impact of in vitro colonic fermentation on the non-bioaccessible fraction.

Potato-based products contribute largely to the daily intake of acrylamide. In addition to potato crisps, the European Commission has included veggie crisps in the list of foods that should be monitored for their acrylamide content. In the present study, acrylamide content in potato and veggie chips (sweet potato, beetroot and carrot) and their bioaccessibility after in vitro digestion was assessed. The non-bioaccessible fraction was also submitted to in vitro fermentation under colonic conditions. Faecal samples from volunteers of three age groups (children, adolescents and adults) were used to evaluate the microbiota effect on the acrylamide availability. Sweet potato chips exhibited the highest acrylamide content (2342 µg/kg), followed by carrot (1279 µg/kg), beetroot (947 µg/kg) and potato chips (524 µg/kg). After in vitro digestion, acrylamide bioaccessibility was significantly lower in veggie chips (59.7-60.4 %) than in potato chips (71.7 %). Potato and sweet potato chips showed the significantly lowest acrylamide content in the non-bioaccessible fraction (22.8 and 24.1 %, respectively) as compared with beetroot chips (28.4 %). After the fermentation step, acrylamide percentage in the soluble fraction of veggie chips ranged from 43.03 to 71.89 %, the highest values being observed in sweet potato chips fermented with microbiota from children. This fact would involve that the acrylamide was released from the non-bioaccessible fractions by the microbiota. These findings point out that the levels of potentially absorbable acrylamide after the complete gastrointestinal process could be modulated by both the food matrix composition and the microbiota. These factors should be further considered for a more precise risk assessment of dietary acrylamide in humans.

Assessment of the acrylamide bioaccessibility in cereal and potato-based foods after in vitro digestion.

Acrylamide bioaccessibility during and after in vitro gastrointestinal digestion of cereal and potato-based foods was monitored. Isolated vs combined meals were evaluated with the aim of investigating acrylamide-food matrix interactions. The meals considered were breakfast cereals, biscuits, patatas a lo pobre (patatas-pobre) and French fries for isolated foods; breakfast cereals with yoghurt, biscuits with milk, patatas-pobre with scrambled eggs and French fries with meat steak for combined foods. The non-bioaccessible fraction of acrylamide tended to decrease during the digestion process in all the systems. However, the final bioaccessible acrylamide was affected by the food matrix composition (fibre, protein, sugars and lipids). The digestion of breakfast cereals, biscuits with milk, patatas-pobre and patatas-pobre with scrambled eggs led to acrylamide bioaccessibility below the initial content of the contaminant in the meals. In absolute values, the combined consumption of biscuits and milk significantly reduced the bioaccessible acrylamide compared with isolated biscuits (from 212 to 122 ng; p < 0.05). The presence of protein sources (egg or meat steak) in the potato-based products significantly decreased the acrylamide bioaccessibility, which was more prominent in the French fries-meat steak system (from 2100 to 1698 ng; p < 0.05). These findings establish the importance of considering complete meals and not only isolated foods as well as the study of the non-bioaccessible fractions for a better understanding of acrylamide bioaccessibility, its recovery and interactions during gastrointestinal digestion.

Molecular markers of putative spermatogonial stem cells in the domestic cat.

Spermatogonial stem cells (SSCs) are an important tool for fertility preservation and species conservation. The ability to expand SSCs by in vitro culture is a crucial premise for their use in assisted reproduction. Because SSCs represent a small proportion of the germ cells in the adult testis, culture success is aided by pre-enrichment through sorting techniques based on cell surface-specific markers. Given the importance of the domestic cat as a model for conservation of endangered wild felids, herein we sought to examine culture conditions as well as molecular markers for cat SSCs. Using a cell culture medium for mouse SSCs supplemented with glial cell-derived neurotrophic factor (GDNF), germ cells from prepuberal cat testes remained viable in culture for up to 43 days. Immunohistochemistry for promyelocytic leukaemia zinc finger (PLZF) protein on foetal, prepuberal and adult testis sections revealed a pattern of expression consistent with the labelling of undifferentiated spermatogonia. Fluorescence-activated cell sorting (FACS) with an antibody against epithelial cell adhesion molecule (EPCAM) was used to sort live cells. Then, the gene expression profile of EPCAM-sorted cells was investigated through RT-qPCR. Notably, EPCAM (+) cells expressed relatively high levels of CKIT (CD117), a surface protein typically expressed in differentiating germ cells but not SSCs. Conversely, EPCAM (-) cells expressed relatively high levels of POU domain class 5 transcription factor 1 (POU1F5 or OCT4), clearly a germ line stem cell marker. These results suggest that cat SSCs would probably be found within the population of EPCAM (-) cells. Future studies should identify additional surface markers that alone or in combination can be used to further enrich SSCs from cat germ cells.

Hipotermia grave como complicación de cetoacidosis diabética / Severe hypothermia as a complication of diabetic ketoacidosis

Se sabe que la diabetes mellitus se acompaña de una serie de alteraciones metabólicas, cardiovasculares y de las funciones neuronales. La cetoacidosis diabética es una de las 3 complicaciones potencialmente mortales de la diabetes mellitus junto a la hipoglucemia y el coma hiperosmolar, y aparece fundamentalmente en pacientes con diabetes mellitus tipo 1 (DM1) o insulinodependientes. Por otra parte, es conocido que algunos pacientes con cetoacidosis diabética presentan una temperatura corporal baja, incluso cuando hay una infección. Sin embargo, no es frecuente que coexista con una situación clínica de hipotermia grave. Presentamos el caso de un paciente que ingresó en nuestra unidad de cuidados intensivos en coma, con cetoacidosis diabética e hipotermia grave (27,6 °C). Revisamos la fisiopatología y el tratamiento de ambas complicaciones cuya asociación es poco frecuente en la práctica clínica habitual (AU)

Análisis de las técnicas continuas de sustitución renal en pacientes críticos con insuficiencia renal aguda / Continuous renal replacement therapies in critically-ill patients with acute renal failure

Fundamento. El fallo renal agudo (FRA) se asocia frecuentemente al síndrome de disfunción multiorgánica (SDMO) en los pacientes críticos. El uso de técnicas continuas de sustitución renal (TCSR) fue descrito por primera vez hace unos 20 años. Analizamos aquí nuestra experiencia valorando los factores pronósticos y la evolución clínica de los pacientes. Pacientes y métodos. Se realizó un estudio descriptivo, observacional y retrospectivo de todos los pacientes críticos con FRA tratados con TCSR, durante el período comprendido entre enero de 1996 y diciembre de 2000. Se recogieron datos demográficos y clínicos, y se realizó un análisis estadístico descriptivo, comparativo y de regresión logística para el estudio de los factores de riesgo relacionados con la mortalidad. Resultados. Fueron evaluados 73 pacientes. La media de edad fue 61 años (intervalo, 17-79), el 62 per cent eran varones, el APACHE II medio fue de 24 (8) y el SAPS II medio fue de 65 (16). La mortalidad global alcanzó el 86,3 per cent. Mediante regresión logística el riesgo de muerte fue más alto en los pacientes con complicaciones relacionadas con la técnica (OR = 2,00; IC del 95 per cent, 1,763-250,0; p = 0,016) y más bajo en pacientes con diuresis residual mayor (OR = 0,995; IC del 95 per cent, 0,990-0,999; p = 0,028). Conclusiones. La mortalidad del FRA que acompaña al SDMO sigue siendo elevada. Las TCSR pueden ser útiles en estos pacientes. En nuestra unidad la ausencia de complicaciones relacionadas con la técnica y la mayor diuresis residual se relacionan con una menor mortalidad. (AU)