640 research outputs found
Iron bioavailability in two commercial cultivars of wheat: a comparison between wholegrain and white flour and the effects of nicotianamine and 2'-deoxymugineic acid on iron uptake into Caco-2 cells
Iron bioavailability in unleavened white and wholegrain bread made from two commercial wheat varieties was assessed by measuring ferritin production in Caco-2 cells. The breads were subjected to simulated gastrointestinal digestion and the digests applied to the Caco-2 cells. Although Riband grain contained a lower iron concentration than Rialto, iron bioavailability was higher. No iron was taken up by the cells from white bread made from Rialto flour or from wholegrain bread from either variety, but Riband white bread produced a small ferritin response. The results probably relate to differences in phytate content of the breads, although iron in soluble monoferric phytate was demonstrated to be bioavailable in the cell model. Nicotianamine, an iron chelator in plants involved in iron transport, was a more potent enhancer of iron uptake into Caco-2 cells than ascorbic acid or 2'-deoxymugineic acid, another metal chelator present in plants
Recognizing and managing a malignant hyperthermia crisis: guidelines from the European Malignant Hyperthermia Group
Survival from a malignant hyperthermia (MH) crisis is highly dependent on early recognition and prompt action. MH crises are very rare and an increasing use of total i.v. anaesthesia is likely to make it even rarer, leading to the potential risk of reduced awareness of MH. In addition, dantrolene, the cornerstone of successful MH treatment, is unavailable in large areas around the world thereby increasing the risk of MH fatalities in these areas. The European Malignant Hyperthermia Group collected and reviewed all guidelines available from the various MH centres in order to provide a consensus document. The guidelines consist of two textboxes: Box 1 on recognizing MH and Box 2 on the treatment of an MH crisi
Genetic reduction of antinutrients in common bean (Phaseolus vulgaris L.) seed, increases nutrients and in vitro iron bioavailability without depressing main agronomic traits
In common bean, lectins, phytic acid, polyphenols and tannins exert major antinutritional effects when
grains are consumed as a staple food. Reduced iron and zinc absorption, low protein digestibility and high
toxicity at the intestinal level are the causes of their antinutritional effect. To improve grain nutritional
characteristics, the “low phytic acid” (lpa) trait recently obtained in bean and carried by the bean mutant
lpa-280-10, was introgressed into different lectin-free (lf) lines, a few of which were white-seeded. The
“white seed coat” (wsc) trait is correlated with a reduced amount of tannins and polyphenols in bean seed,
and thus higher Fe bioavailability. Lf + lpa bean lines producing colored and white seeds, were developed.
Three of these lines were submitted to a first field performance test carried out in two Italian locations, and
two of them to biochemical analyses that evaluated fourteen nutritional parameters. Seedling emergence
and grain yield of lf + lpa beans were statistically comparable to those of wild type cultivars, confirming the
absence of major agronomic defects associated with the lpa trait. The presence of the three genetic traits
lf, lpa and wsc in the same genetic background leads to a significant increase of the content of important
nutrients such as crude proteins, total zinc, free phosphorus, and, in part, total iron. Iron bioavailability (as
measured in vitro via a Caco-2 cell model) in lf + lpa brown and black seeds, was not significantly different
from that surveyed in the wild type colored parents, while, it was on average twelve times higher in
lf + lpa white bean seeds. Up to now, the white-seeded lf + lpa beans seem thus to be the only materials
having really improved nutritional qualities
Multi-Region Hemispheric Specialization Differentiates Human from Nonhuman Primate Brain Function
The human behavioral repertoire greatly exceeds that of nonhuman primates. Anatomical specializations of the human brain include an enlarged neocortex and prefrontal cortex (Semendeferi et al. in Am J Phys Anthropol 114:224–241, 2001), but regional enlargements alone cannot account for these vast functional differences. Hemispheric specialization has long believed to be a major contributing factor to such distinctive human characteristics as motor dominance, attentional control and language. Yet structural cerebral asymmetries, documented in both humans and some nonhuman primate species, are relatively minor compared to behavioral lateralization. Identifying the mechanisms that underlie these functional differences remains a goal of considerable interest. Here, we investigate the intrinsic connectivity networks in four primate species (humans, chimpanzees, baboons, and capuchin monkeys) using resting-state fMRI to evaluate the intra- and inter- hemispheric coherences of spontaneous BOLD fluctuation. All three nonhuman primate species displayed lateralized functional networks that were strikingly similar to those observed in humans. However, only humans had multi-region lateralized networks, which provide fronto-parietal connectivity. Our results indicate that this pattern of within-hemisphere connectivity distinguishes humans from nonhuman primates
Means and covariance functions for geostatistical compositional data: an axiomatic approach
This work focuses on the characterization of the central tendency of a sample
of compositional data. It provides new results about theoretical properties of
means and covariance functions for compositional data, with an axiomatic
perspective. Original results that shed new light on the geostatistical
modeling of compositional data are presented. As a first result, it is shown
that the weighted arithmetic mean is the only central tendency characteristic
satisfying a small set of axioms, namely continuity, reflexivity and marginal
stability. Moreover, this set of axioms also implies that the weights must be
identical for all parts of the composition. This result has deep consequences
on the spatial multivariate covariance modeling of compositional data. In a
geostatistical setting, it is shown as a second result that the proportional
model of covariance functions (i.e., the product of a covariance matrix and a
single correlation function) is the only model that provides identical kriging
weights for all components of the compositional data. As a consequence of these
two results, the proportional model of covariance function is the only
covariance model compatible with reflexivity and marginal stability
Biofortified red mottled beans (Phaseolus vulgaris L.) in a maize and bean diet provide more bioavailable iron than standard red mottled beans: Studies in poultry (Gallus gallus) and an in vitro digestion/Caco-2 model
<p>Abstract</p> <p>Background</p> <p>Our objective was to compare the capacities of biofortified and standard colored beans to deliver iron (Fe) for hemoglobin synthesis. Two isolines of large-seeded, red mottled Andean beans (<it>Phaseolus vulgaris </it>L.), one standard ("Low Fe") and the other biofortified ("High Fe") in Fe (49 and 71 μg Fe/g, respectively) were used. This commercial class of red mottled beans is the preferred varietal type for most of the Caribbean and Eastern and Southern Africa where almost three quarters of a million hectares are grown. Therefore it is important to know the affect of biofortification of these beans on diets that simulate human feeding studies.</p> <p>Methods</p> <p>Maize-based diets containing the beans were formulated to meet the nutrient requirements for broiler except for Fe (Fe concentrations in the 2 diets were 42.9 ± 1.2 and 54.6 ± 0.9 mg/kg). One day old chicks (<it>Gallus gallus</it>) were allocated to the experimental diets (n = 12). For 4 wk, hemoglobin, feed-consumption and body-weights were measured.</p> <p>Results</p> <p>Hemoglobin maintenance efficiencies (HME) (means ± SEM) were different between groups on days 14 and 21 of the experiment (P < 0.05). Final total body hemoglobin Fe contents were different between the standard (12.58 ± 1.0 mg {0.228 ± 0.01 μmol}) and high Fe (15.04 ± 0.65 mg {0.273 ± 0.01 μmol}) bean groups (P < 0.05). At the end of the experiment, tissue samples were collected from the intestinal duodenum and liver for further analyses. Divalent-metal-transporter-1, duodenal-cytochrome-B, and ferroportin expressions were higher and liver ferritin was lower (P < 0.05) in the standard group vs. the biofortified group. <it>In-vitro </it>analysis showed lower iron bioavailability in cells exposed to standard ("Low Fe") bean based diet.</p> <p>Conclusions</p> <p>We conclude that the <it>in-vivo </it>results support the <it>in-vitro </it>observations; biofortified colored beans contain more bioavailable-iron than standard colored beans. In addition, biofortified beans seems to be a promising vehicle for increasing intakes of bioavailable Fe in human populations that consume these beans as a dietary staple. This justifies further work on the large-seeded Andean beans which are the staple of a large-region of Africa where iron-deficiency anemia is a primary cause of infant death and poor health status.</p
Stochastic simulation of soil particle-size curves in heterogeneous aquifer systems through a Bayes space approach
We address the problem of stochastic simulation of soil particle-size curves (PSCs) in heterogeneous
aquifer systems. Unlike traditional approaches that focus solely on a few selected features of PSCs
(e.g., selected quantiles), our approach considers the entire particle-size curves and can optionally include
conditioning on available data. We rely on our prior work to model PSCs as cumulative distribution functions
and interpret their density functions as functional compositions. We thus approximate the latter
through an expansion over an appropriate basis of functions. This enables us to (a) effectively deal with the
data dimensionality and constraints and (b) to develop a simulation method for PSCs based upon a suitable
and well defined projection procedure. The new theoretical framework allows representing and reproducing
the complete information content embedded in PSC data. As a first field application, we demonstrate
the quality of unconditional and conditional simulations obtained with our methodology by considering a
set of particle-size curves collected within a shallow alluvial aquifer in the Neckar river valley, Germany
P-selectin Expression Tracks Cerebral Atrophy in Mexican-Americans
Background and Purpose: We hypothesized that the P-selectin (SELP) gene, localized to a region on chromosome 1q24, pleiotropically contributes to increased blood pressure and cerebral atrophy. We tested this hypothesis by performing genetic correlation analyses for 13 mRNA gene expression measures from P-selectin and 11 other genes located in 1q24 region and three magnetic resonance imaging derived indices of cerebral integrity. Methods: The subject pool consisted of 369 (219F; aged 28–85, average = 47.1 ± 12.7 years) normally aging, community-dwelling members of large extended Mexican-American families. Genetic correlation analysis decomposed phenotypic correlation coefficients into genetic and environmental components among 13 leukocyte-based mRNA gene expressions and three whole-brain and regional measurements of cerebral integrity: cortical gray matter thickness, fractional anisotropy of cerebral white matter, and the volume of hyperintensive WM lesions. Results: From the 13 gene expressions, significant phenotypic correlations were only found for the P- and L-selectin expression levels. Increases in P-selectin expression levels tracked with decline in cerebral integrity while the opposite trend was observed for L-selectin expression. The correlations for the P-selectin expression were driven by shared genetic factors, while the correlations with L-selectin expression were due to shared environmental effects. Conclusion: This study demonstrated that P-selectin expression shared a significant variance with measurements of cerebral integrity and posits elevated P-selectin expression levels as a potential risk factor of hypertension-related cerebral atrophy
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