The Experts below are selected from a list of 318 Experts worldwide ranked by ideXlab platform
Hiroshi Ikehashi - One of the best experts on this subject based on the ideXlab platform.
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Phosphorus deficiency-induced root elongation and its QTL in rice (Oryza sativa L.).
Theoretical and Applied Genetics, 2004Co-Authors: Akifumi Shimizu, Seiji Yanagihara, Shinji Kawasaki, Hiroshi IkehashiAbstract:A significant level of root elongation was induced in rice (Oryza sativa) grown under phosphorus-deficient conditions. The root elongation clearly varied among a total of 62 varieties screened under two different phosphorus levels. Two contrasting varieties, ‘Gimbozu’, with a low elongating response and ‘Kasalath’, with a high elongating response, were chosen and crossed to produce a hybrid population for QTL analyses. QTLs for the phosphorus deficiency-induced root elongation were detected by two linkage maps, i.e., one with 82 F3 families constructed by 97 simple sequence repeat (SSR) and sequence-tag site markers and another with 97 F8 lines by 790 amplified fragment length polymorphism and SSR markers. A single QTL for the elongation response was detected on chromosome 6, with a LOD score of 4.5 in both maps and explained about 20% of total phenotypic variance. In addition, this QTL itself, or a region tightly linked with it, partly explained an ability to reduce accumulation of excess iron in the shoots. The identified QTL will be useful to improve rice varieties against a complex Nutritional Disorder caused by phosphorus deficiency and iron toxicity.
Mathieu Torck - One of the best experts on this subject based on the ideXlab platform.
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Vitamin C deficiency: more than just a Nutritional Disorder.
Genes & nutrition, 2011Co-Authors: Joris R. Delanghe, Michel Langlois, Marc De Buyzere, Jin Ouyang, Marijn M. Speeckaert, Mathieu TorckAbstract:Although vitamin C deficiency and scurvy are generally considered as pure Nutritional Disorders, only a minority of the vitamin C concentration is determined by food intake. In the presence of transition metals (iron and copper), the antiscorbutic factor shifts from an antioxidant to a pro-oxidant function. Haptoglobin (Hp) is a plasma α-2 glycoprotein characterized by 3 common phenotypes (Hp 1–1, Hp 2–1 and Hp 2–2). Its free hemoglobin (Hb)-binding capacity prevents Hb-driven oxidative damage. When the antioxidant capacity of Hp is insufficient, its role is taken over by hemopexin (heme-binding protein) and by vitamin C (free radical scavenger). The Hp 2–2 phenotype has a lower capacity to inhibit oxidation and vitamin C depletion. In this article, two consequences of this major finding are tackled. The Hp polymorphism is an important non-Nutritional modifying factor in the pathogenesis of vitamin C deficiency and scurvy, which may explain the success of long-range human migration by the natural selection of some populations characterized by high Hp 1 allele frequencies. Moreover, we propose tailoring the recommended dietary allowance (RDA) values of vitamin C, taking into consideration the Hp phenotype dependency.
Akifumi Shimizu - One of the best experts on this subject based on the ideXlab platform.
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Phosphorus deficiency-induced root elongation and its QTL in rice (Oryza sativa L.).
Theoretical and Applied Genetics, 2004Co-Authors: Akifumi Shimizu, Seiji Yanagihara, Shinji Kawasaki, Hiroshi IkehashiAbstract:A significant level of root elongation was induced in rice (Oryza sativa) grown under phosphorus-deficient conditions. The root elongation clearly varied among a total of 62 varieties screened under two different phosphorus levels. Two contrasting varieties, ‘Gimbozu’, with a low elongating response and ‘Kasalath’, with a high elongating response, were chosen and crossed to produce a hybrid population for QTL analyses. QTLs for the phosphorus deficiency-induced root elongation were detected by two linkage maps, i.e., one with 82 F3 families constructed by 97 simple sequence repeat (SSR) and sequence-tag site markers and another with 97 F8 lines by 790 amplified fragment length polymorphism and SSR markers. A single QTL for the elongation response was detected on chromosome 6, with a LOD score of 4.5 in both maps and explained about 20% of total phenotypic variance. In addition, this QTL itself, or a region tightly linked with it, partly explained an ability to reduce accumulation of excess iron in the shoots. The identified QTL will be useful to improve rice varieties against a complex Nutritional Disorder caused by phosphorus deficiency and iron toxicity.
Emmanuel Delaporte - One of the best experts on this subject based on the ideXlab platform.
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Severe scurvy: an underestimated disease
European journal of clinical nutrition, 2015Co-Authors: M Levavasseur, C. Becquart, E Pape, Marie Pigeyre, J. Rousseaux, D. Staumont-sallé, Emmanuel DelaporteAbstract:Scurvy is one of the oldest diseases in human history. Nowadays, although scurvy tends to become a forgotten disease in developed country, rare cases still occur, especially in people undergoing extreme diet, old people or children with poor diet and patients with malabsorption. We describe three cases of scurvy. The first case is a patient diagnosed with Crohn’s disease, the second one is in a context of anorexia nervosa and drug addiction, and the third case is in a context of social isolation. Early recognition of scurvy can be difficult because symptoms may appear nonspecific and can mimic more common conditions. In any patient with spontaneous hematoma and purpura, in the context of Nutritional Disorder, scurvy should be systematically considered. As this disease can lead to severe complications, such as bone pain, heart failure or gastrointestinal symptoms, nothing should delay vitamin C supplementation, which is a simple and rapidly effective treatment.
Joris R. Delanghe - One of the best experts on this subject based on the ideXlab platform.
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Vitamin C deficiency: more than just a Nutritional Disorder.
Genes & nutrition, 2011Co-Authors: Joris R. Delanghe, Michel Langlois, Marc De Buyzere, Jin Ouyang, Marijn M. Speeckaert, Mathieu TorckAbstract:Although vitamin C deficiency and scurvy are generally considered as pure Nutritional Disorders, only a minority of the vitamin C concentration is determined by food intake. In the presence of transition metals (iron and copper), the antiscorbutic factor shifts from an antioxidant to a pro-oxidant function. Haptoglobin (Hp) is a plasma α-2 glycoprotein characterized by 3 common phenotypes (Hp 1–1, Hp 2–1 and Hp 2–2). Its free hemoglobin (Hb)-binding capacity prevents Hb-driven oxidative damage. When the antioxidant capacity of Hp is insufficient, its role is taken over by hemopexin (heme-binding protein) and by vitamin C (free radical scavenger). The Hp 2–2 phenotype has a lower capacity to inhibit oxidation and vitamin C depletion. In this article, two consequences of this major finding are tackled. The Hp polymorphism is an important non-Nutritional modifying factor in the pathogenesis of vitamin C deficiency and scurvy, which may explain the success of long-range human migration by the natural selection of some populations characterized by high Hp 1 allele frequencies. Moreover, we propose tailoring the recommended dietary allowance (RDA) values of vitamin C, taking into consideration the Hp phenotype dependency.