180 research outputs found

    Protein quality of amaranth grains cultivated in Ethiopia as affected by popping and fermentation

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    The effect of popping and fermentation on protein quality of three different varieties of amaranth grains cultivated in Ethiopia was evaluated. Total lysine content of the grains was higher than that of commonly available cereals but close to that of legumes. Methionine and cysteine contents in the grains were also higher than that found in cereal and legume proteins. Percentage of total indispensable amino acids, excluding tryptophan, was 43% - 49%, which was higher than WHO reference pattern (31%). Popping resulted in 36% and 37% reduction in total lysine and cysteine contents, respectively, whereas fermentation reduced cysteine, lysine and methionine contents by 16%, 20% and 20%, respectively. From the free amino acids, histidine was the major indispensable amino acid but threonine was not detected. During popping, all free amino acids, except threonine, were reduced. On the other hand, fermentation significantly increased (p < 0.01) most amino acids except arginine, which was significantly decreased (p < 0.01), and tyrosine and glutamic acid, for which no change was observed. Popping decreased in vitro protein digestibility (IVPD) by 8.3% - 17.1% while fermentation increased IVPD by 4.8% - 7.5%. Substitution of amaranth for wheat and/or maize during complementary food formulation could contribute much to the daily requirements of indispensable amino acids of young children

    Nonbreast-fed, HIV-1-exposed Burkinabe infants have low energy intake between 6 and 11 months of age despite free access to infant food aid

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    In a WHO coordinated, mother-to-child HIV transmission (MTCT) prevention trial in Burkina Faso, HIV-1 nfected mothers were adv sed to either stop breast-feeding oy 6 mo or totally avoid it. Participants were prov ded with cereal-based, infant fortified mix (IFM) from 6 to 12 mo postpartum along with infant feeding counseling. Our objective was to describe ronbreast-fed infants food consumption and adecuacy of nutrient intake. A 1-d weighed food record and one 24 h dietary recall were performed in 68 nonbreast-fed, non-HIV infected 6- to 11-mo-old infants. Mean food enemy density and feeding frequency were satisfactory n 6-8 mo ods [0.8 +/- 0.2 kcal/g (3.3 +/- 0.9 kJ/g) and 7.2 +/- 1.6 times/c] and n 9-11 moods [0.9 +/- 0.2 kcal/lg (3.6 +/- 0.8 kJ/g) and 7.7 +/- 2 1 times/d]. Median energy intake was 523 Kcal [range 82-1053 (2187 kJ, range: 345-4401)] in 6-8- and 811 kcal [range: 34-1543 (3392 kJ, range: 144-6452)] n 9-11-mo-old infants, respectively. Approximately 75% of their energy intake was provided by subsidized foods (milk that mothers obta ned from support networks and IFM). One-has of the infants had intakes < 80 kcal/kg (<334 kJ/kg) on the day of the survey, mainly because IFM and milk were consumed in amounts that were too low. Thus, coverage of energy needs required a diet with sufficient amounts of both IFM and milk in these vulnerable infants. These findings argue for the development of adequate, sustainable infant fort fed foods and their rapid integration into MTCT prevent on services They also lend support to the recent revision of WHO infant feeding guidance for future MTCT prevention programming that recommends breast-feeding up to 12 me postpartum (under cover of antiretroviral prophylaxis) as the safest feeding option for infants of HIV-infected mothers. J. Nutr. 141: 674-679, 2011

    Increasing pulse agrobiodiversity to improve food security and sustainable agriculture in Sub-Saharan Africa

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    Long-life cycle pulses have significant food security potential, however, there is little evidence to explain why they are not more widely produced and consumed in sub-Saharan Africa (SSA). This study aimed at exploring existing knowledge to inform on future research priorities in mainstreaming superior species. As staple food along with cereals, pulses are an important source of nutrients whose intake is often inadequate in SSA, however, pulse consumption remain inadequate in SSA. Depending on the crop's life cycle, pulses have multiple functions that can support food systems and ecosystem resilience. Compared to short-life cycle pulses, long-life cycle pulses rank higher in multipurpose role. However, prior research has focused primarily on short-life cycle pulses due to rapid grain production. Long-life cycle pulses remain underutilized and neglected despite showing steady but modest yield increases and adaptation to environments, suggesting that they are better positioned to respond to the diverse needs of smallholder farmers in SSA. In the context of climate change, rain-fed agriculture, depleted agricultural soils, and lack of subsidized fertilizers, there is need to transform existing food systems toward sustainable food production and improved resilience. Increasing pulse agrobiodiversity by integrating long-life cycle pulses in existing farming systems could not only contribute in alleviating malnutrition, but also poverty and inequalities. In addition, representative and accurate data are needed based on the correct use of accepted scientific names for all data across the food system. This is a prerequisite for assessing pulse consumption adequacy and quantifying production and consumption trends

    The ecological causes of functional distinctiveness in communities

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    Recent work has shown that evaluating functional trait distinctiveness, the average trait distance of a species to other species in a community offers promising insights into biodiversity dynamics and ecosystem functioning. However, the ecological mechanisms underlying the emergence and persistence of functionally distinct species are poorly understood. Here, we address the issue by considering a heterogeneous fitness landscape whereby functional dimensions encompass peaks representing trait combinations yielding positive population growth rates in a community. We identify four ecological cases contributing to the emergence and persistence of functionally distinct species. First, environmental heterogeneity or alternative phenotypic designs can drive positive population growth of functionally distinct species. Second, sink populations with negative population growth can deviate from local fitness peaks and be functionally distinct. Third, species found at the margin of the fitness landscape can persist but be functionally distinct. Fourth, biotic interactions (positive or negative) can dynamically alter the fitness landscape. We offer examples of these four cases and guidelines to distinguish between them. In addition to these deterministic processes, we explore how stochastic dispersal limitation can yield functional distinctiveness. Our framework offers a novel perspective on the relationship between fitness landscape heterogeneity and the functional composition of ecological assemblages

    Contrasted Effects of Diversity and Immigration on Ecological Insurance in Marine Bacterioplankton Communities

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    The ecological insurance hypothesis predicts a positive effect of species richness on ecosystem functioning in a variable environment. This effect stems from temporal and spatial complementarity among species within metacommunities coupled with optimal levels of dispersal. Despite its importance in the context of global change by human activities, empirical evidence for ecological insurance remains scarce and controversial. Here we use natural aquatic bacterial communities to explore some of the predictions of the spatial and temporal aspects of the ecological insurance hypothesis. Addressing ecological insurance with bacterioplankton is of strong relevance given their central role in fundamental ecosystem processes. Our experimental set up consisted of water and bacterioplankton communities from two contrasting coastal lagoons. In order to mimic environmental fluctuations, the bacterioplankton community from one lagoon was successively transferred between tanks containing water from each of the two lagoons. We manipulated initial bacterial diversity for experimental communities and immigration during the experiment. We found that the abundance and production of bacterioplankton communities was higher and more stable (lower temporal variance) for treatments with high initial bacterial diversity. Immigration was only marginally beneficial to bacterial communities, probably because microbial communities operate at different time scales compared to the frequency of perturbation selected in this study, and of their intrinsic high physiologic plasticity. Such local “physiological insurance” may have a strong significance for the maintenance of bacterial abundance and production in the face of environmental perturbations

    Vaccine breakthrough hypoxemic COVID-19 pneumonia in patients with auto-Abs neutralizing type I IFNs

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    Life-threatening `breakthrough' cases of critical COVID-19 are attributed to poor or waning antibody response to the SARS- CoV-2 vaccine in individuals already at risk. Pre-existing autoantibodies (auto-Abs) neutralizing type I IFNs underlie at least 15% of critical COVID-19 pneumonia cases in unvaccinated individuals; however, their contribution to hypoxemic breakthrough cases in vaccinated people remains unknown. Here, we studied a cohort of 48 individuals ( age 20-86 years) who received 2 doses of an mRNA vaccine and developed a breakthrough infection with hypoxemic COVID-19 pneumonia 2 weeks to 4 months later. Antibody levels to the vaccine, neutralization of the virus, and auto- Abs to type I IFNs were measured in the plasma. Forty-two individuals had no known deficiency of B cell immunity and a normal antibody response to the vaccine. Among them, ten (24%) had auto-Abs neutralizing type I IFNs (aged 43-86 years). Eight of these ten patients had auto-Abs neutralizing both IFN-a2 and IFN-., while two neutralized IFN-omega only. No patient neutralized IFN-ss. Seven neutralized 10 ng/mL of type I IFNs, and three 100 pg/mL only. Seven patients neutralized SARS-CoV-2 D614G and the Delta variant (B.1.617.2) efficiently, while one patient neutralized Delta slightly less efficiently. Two of the three patients neutralizing only 100 pg/mL of type I IFNs neutralized both D61G and Delta less efficiently. Despite two mRNA vaccine inoculations and the presence of circulating antibodies capable of neutralizing SARS-CoV-2, auto-Abs neutralizing type I IFNs may underlie a significant proportion of hypoxemic COVID-19 pneumonia cases, highlighting the importance of this particularly vulnerable population
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