23 research outputs found

    Fluoride uptake and translocation in food crops grown in fluoride-rich soils.

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    This research article published by John Wiley & Sons, Inc., 2020BACKGROUND The East African Rift Valley (EARV) area is characterized by an intense volcanic activity, which largely influences the nature of soils, ground and surface waters causing a transfer of fluoride from volcanic emissions to the environment. Field experiments were conducted in F‐contaminated areas of Ngarenanyuki (Arumeru district) in North Tanzania. In order to evaluate the potential fluoride exposure from the diet and the related health risk for the local population, the content of fluoride in soil and plant tissues was assessed, focusing on the edible portions (leaves, fruits or seeds) of the main cultivated and consumed food crops in the area. RESULTS Average fluoride contents of 8.0, 11.4, 11.3 and 14.2 mg kg−1 of dry matter were observed respectively for maize (Zea mays L.), tomato (Lycopersicon esculentum Mill.), bean (Phaseolus vulgaris L.) and kale (Brassica sp. pl .) edible parts. The cumulative estimated average daily dose (EADD) ranged from 0.026 to 0.165 mg F d−1 kg−1 among different rural population groups and considering two different hypotheses of absorption fraction (75% or 100%), i.e. the amount of fluoride that is absorbed during the digestion process. The associated hazard index (HI) values varied from 0.43 to 2.75. CONCLUSIONS Considering the dietary habits of the local population, the outcomes of the present study suggest that the investigated crops can substantially contribute to fluoride related diseases, especially in earlier ages

    Original Article

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    The present paper deals with an investigation on the changes appearing in the mucous membrane of the nose (physiologic atrophy) in normal persons of different age groups, as contrasted with a wasting of the mucous mambrane of the nose in cases of atrophic rhinitis. The investigation has been performed for the purpose of contributing to the studies of the pathology of atrophic rhinitis. 1. Pathologic changes of a considerable degree were. observed in the epithelium in quite a large section of infants and children where it had been considered normal as a results of macroscopic examinations. 2. Metaplasia of the epithelial cells developing in the mucous membrane in the forepart of the respiratory region seems to occur as a result of the stimulus applied from without. The phenomenon was marked in the front and along the lower edge of the inferior turbinal, showing a tendency to increase in magnitude as the age advance. It did not, however, spread over a wide area, nor was there any marked development of cornification. An increase in mucus secretion, as well as in the number of goblet cells, was noticed in the epithelium as the age advance. Mucous degeneration gradually set in at the end of forties, becoming marked in the sixties. 4. In the basal membrane, the hyaline layer, which is its secondary form, grew in size with age, and a substance which stains with Hale\u27s stain was detected in it. This substance seems to have an important share in the mucus secreting function of the epithelium. 5. It seems that the epithelium of the mucous membrane of the upper respiratory tract continues to function even in considerably advanced ages. 6. The lymphoid tissue situated underneath the epithelium attained the largest quantity in persons about 20 years old; it began to diminish and grow less thick in persons over 40. The presence of the elastic fiber was noticed in the subepithelial layer in all age groups, though the number of persons with this phenomenon was small.7. The glands wers under-developed in children of about 10; they grew rapidly after that age until about 40 when they began to show a tendency to atrophy. 8. It seems that the periglandular lymphocytes, which infiltrate without bringing about the disintegration of the glands, take charge of the metabolism of the glands. A large number of them were found in infancy but they showed a marked decrease in number in persons over about 40. It would seem that, in highly advanced ages, non-inflammatory disintegration of the glands could possibly occur as a result of the infiltration of the lymphoid tissue. 9. The formation of the oncocyte, an unusual cell of the epithelium of the gland which characterizes the old age, was noticed in 7 cases. 10. The blood vessels manifested changes of a high degree in persons of advanced ages: they revealed evidences of functional disturbance of a high degree when stained by the stains of H. E, Weigert, PAS and Hale. This would show the measure of the influence that has been exerted on the function of the mucous membrane. 11. Corpora cavernosa was under-developed in infancy but became well-developed in persons of about 20; a decrease in the number of bodies and a diminution in size of the inner lumen became marked in persons over 40, becoming more marked in persons over 50

    The Constrained Maximal Expression Level Owing to Haploidy Shapes Gene Content on the Mammalian X Chromosome.

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    X chromosomes are unusual in many regards, not least of which is their nonrandom gene content. The causes of this bias are commonly discussed in the context of sexual antagonism and the avoidance of activity in the male germline. Here, we examine the notion that, at least in some taxa, functionally biased gene content may more profoundly be shaped by limits imposed on gene expression owing to haploid expression of the X chromosome. Notably, if the X, as in primates, is transcribed at rates comparable to the ancestral rate (per promoter) prior to the X chromosome formation, then the X is not a tolerable environment for genes with very high maximal net levels of expression, owing to transcriptional traffic jams. We test this hypothesis using The Encyclopedia of DNA Elements (ENCODE) and data from the Functional Annotation of the Mammalian Genome (FANTOM5) project. As predicted, the maximal expression of human X-linked genes is much lower than that of genes on autosomes: on average, maximal expression is three times lower on the X chromosome than on autosomes. Similarly, autosome-to-X retroposition events are associated with lower maximal expression of retrogenes on the X than seen for X-to-autosome retrogenes on autosomes. Also as expected, X-linked genes have a lesser degree of increase in gene expression than autosomal ones (compared to the human/Chimpanzee common ancestor) if highly expressed, but not if lowly expressed. The traffic jam model also explains the known lower breadth of expression for genes on the X (and the Z of birds), as genes with broad expression are, on average, those with high maximal expression. As then further predicted, highly expressed tissue-specific genes are also rare on the X and broadly expressed genes on the X tend to be lowly expressed, both indicating that the trend is shaped by the maximal expression level not the breadth of expression per se. Importantly, a limit to the maximal expression level explains biased tissue of expression profiles of X-linked genes. Tissues whose tissue-specific genes are very highly expressed (e.g., secretory tissues, tissues abundant in structural proteins) are also tissues in which gene expression is relatively rare on the X chromosome. These trends cannot be fully accounted for in terms of alternative models of biased expression. In conclusion, the notion that it is hard for genes on the Therian X to be highly expressed, owing to transcriptional traffic jams, provides a simple yet robustly supported rationale of many peculiar features of X's gene content, gene expression, and evolution

    Impacts of fluoride contamination on food crops grown in rural areas of the African Rift Valley

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    The consumption of fluoride-rich food products can represent a major source of fluoride (F) exposure for humans, contributing, together with the consumption of F-rich drinking-water, to enhance the hazard of incurring severe diseases known under the name of endemic fluorosis. Even though the connection between the environmental F contamination and the fluorosis disease is well recognised, the analyses of literature brought to the light the gap of knowledge on the uptake behaviour and the effects of F on food crops, particularly regarding some of the strongest affected areas, such as the East African Rift Valley. Field experiments conducted in rural areas of North Tanzania confirmed, as previous observed in the literature, the tendency of plants to accumulate F mostly in the root system to the disadvantage of those crops whose edible part is the underground organs. However, a substantial accumulation of F in other plants edible parts (e.g. leaves, fruits or seeds) was also observed, underlining that the consumption of the considered food items can substantially contribute to F-correlated diseases, especially in earlier ages. Moreover, the protracted use of high-F contaminated waters along the crop cycle, as tested in a greenhouse pot experiment, was observed to considerably affect the quality of the soil leading to a significant rise of its water-soluble F concentration and the increase of F accumulation in plants organs such leaves and stems in a dose-dependent manner

    Introducing Fonio in the farming system to enhance food security and Incomes in Northern Ghana and Burkina Faso

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    The practice Abstract n. 1 of EWA-BELT Project describes the potentialities and opportunities of Fonio and selected varieties to improve food security during the planting and harvesting season in West Africa.The Practice Abstract is available and published within the EIP-AGRI Initiative, here: https://ec.europa.eu/eip/agriculture/en/find-connect/projects/linking-east-and-west-african-farming-systems.htm

    Land degradation and the upper hand of sustainable agricultural intensification in sub-Saharan Africa - A systematic review

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    Sub-Saharan Africa (SSA) faces severe land degradation, driven by a combination of human and natural factors. Deforestation, inadequate land management practices, and unsustainable farming methods are the primary causes. The historical trends reveal the impact of soil erosion and nutrient depletion on 70% of the soil and 65% of its total land area. Unchecked degradation poses a critical threat to economic growth and poverty reduction initiatives. The region's food security is intricately linked to the complex interplay between land degradation and a rapidly growing population. Escalating demand for agricultural resources raises concerns about the ability to meet the needs of SSA's population. The adoption of sustainable agricultural intensification practices (SIAP) emerges as a crucial strategy to address land degradation and enhance food security. SIAP involves innovative and ecologically sensitive techniques, such as agroforestry and organic farming, targeting to optimise resource use and minimise negative impacts on soil health. The interconnectedness between factors of land degradation, food security, and the contribution of SIAP underscores the urgency of adopting sustainable practices to ensure a balanced relationship between agricultural productivity and environmental conservation in SSA. While SIAP holds promise, challenges such as socio-economic barriers, low adoption rates, and contextual variations necessitate continuous support and well-designed policies for successful implementation

    Sustainable fonio value chain development in Ghana

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    <p><i>Factsheet 2 is dedicated to the sustainable fonio value chain development in Ghana. </i></p><p>Fonio has gained attention in recent years as a nutritious and sustainable crop that could help address food security and nutritional challenges in West Africa and beyond. It offers an alternative to more common cereals like sorghum, millet, wheat, rice, and maize and can grow on marginal lands. Despite the great benefits associated with the crop, fonio is under-exploited and is considered to be an underutilized crop species in Africa. A study by the EWA-BELT project funded by EU horizon 2020 (GA 862848) has analysed the fonio value chain in Ghana in order to identify what opportunities and barriers exist for more widespread uptake. </p><p>The introduction of cost-effective, labour-saving mechanisation at the production and processing stages of the value chain, along with access to the credit facility, improved seed, and enhanced knowledge on good agronomic practices, could significantly boost the value chain in Ghana. Marketing and promotion campaigns should be conducted to create awareness of the potential of the fonio value chain. Collective marketing and contract production could solve some of the marketing challenges of the fonio value chain. Capacity building amongst farmers and improved processing is needed. Increased funding for fonio research is recommended to develop new and improved varieties.</p&gt

    Fonio VCA - Sustainable fonio value chain development in Ghana

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    <p><i>Policy Brief 2 is dedicated to the value chain development of Fonio in Ghana.</i></p><p>Fonio has gained attention in recent years as a nutritious and sustainable crop that could help address food security and nutritional challenges in West Africa and beyond. It offers an alternative to more common cereal grains like sorghum, millet, wheat, rice, and maize and can thrive well on marginal lands. Despite the great benefits associated with the crop it is under exploited and considered an underutilized crop species especially in Africa. A study by the EWA-BELT project funded by EU horizon 2020 has analysed the fonio value chain in Ghana and has made recommendations for the boosting of the value chain in Ghana which are presented in this policy brief. The key messages include;</p><ul><li>The factors limiting fonio value chain development include lack of modern farming equipment's, inadequate farming and market information, and less interaction among the chain actors.</li><li>Birds attach is one major limiting factor of fonio production.</li><li>Processing of fonio is labour intensive</li><li>Poor product quality has been observed in fonio VC.</li><li>All nodes of the fonio VC are profitable.</li><li>The introduction of cost-effective, labour-friendly mechanisation services at the various stages of the value chain, along with access to the credit facility, improved seed, and enhanced knowledge on good agronomic practices, will significantly boost the chain.</li></ul><p>It is recommended that marketing and promotion campaigns must be carried out to create awareness of the potential of the fonio value chain. Collective marketing and contract production is recommended as a remedy to the marketing challenges of the fonio value chain at the aggregation and trading nodes. Capacity building at the production and processing nodes is strongly recommended. Increase funding to fonio research is highly recommended for the development of new and improved varieties and new recipes.</p&gt
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