Iron is a critical micronutrient, and iron derived from heme contributes a large proportion of the total iron absorbed in a typical Western diet. Heme iron is absorbed by different mechanisms than non-heme iron, but d...Iron is a critical micronutrient, and iron derived from heme contributes a large proportion of the total iron absorbed in a typical Western diet. Heme iron is absorbed by different mechanisms than non-heme iron, but despite considerable study over many years these mechanisms remain poorly understood. This review provides an overview of the importance of heme iron in the diet and discusses the two prevailing hypotheses of heme absorption; namely receptor mediated endocytosis of heme, and direct transport into the intestinal enterocyte by recently discovered heme transporters. A specific emphasis is placed on the questions surrounding the site of heme catabolism and the identity of the enzyme that performs this task. Additionally, we present the hypothesis that a non-heme iron transport protein may be required for heme iron absorption and discuss the experiences of our laboratory in examining this hypothesis.展开更多
Fe, Chlorophyll (Chl) and total nitrogen (TN) content in tissues were measured in Fe-deficient cultures of Ulva. pertusa over a period of 60 days. Photosynthetic carbon fixation rates were studied at the start of and ...Fe, Chlorophyll (Chl) and total nitrogen (TN) content in tissues were measured in Fe-deficient cultures of Ulva. pertusa over a period of 60 days. Photosynthetic carbon fixation rates were studied at the start of and 30 days after Fe-deficiency culture, when the effects of Fe-deficiency on the ultrastructure were also analyzed. The iron content in tissue decreased exponentially during Fe-deficiency (from 726.7 to 31.6 μg/gdw) and simultaneously Chl and TN content declined to 4.35% and 59.9% of their original levels respectively. Maximum carbon fixation rate (50-250 μmol/m 2 s) under Fe-deficiency decreased significantly compared with the control (p<0.01) and was 13.6 to 0.365 μg C /cm 2 h. Photosynthesis in Fe-deficient cells became light-saturated at lower irradiance than that in control. Ultrastructural observations of Fe-deficient cells showed reductions in chloroplast number, some degeneration of lamellar organization, an increase in vacuolar area, a decrease in mitochondrial matrix density, and variation in accumulation body number and morphology. During Fe-deficiency, the algae growth rate continued to decline and after 6 weeks of iron deficiency, no further growth was detectable. These suggested that the lower growth rate of Ulva. pertusa under Fe-deficiency could be due mainly to nitrogen utilization and inhibition of photosynthesis.展开更多
The study was performed to determine whether the srum concentrations of IL （interleukin）-6 are elevated in patients with RA （rheumatoid arthritis） and to investigate the relationship between IL-6 levels and iron s...The study was performed to determine whether the srum concentrations of IL （interleukin）-6 are elevated in patients with RA （rheumatoid arthritis） and to investigate the relationship between IL-6 levels and iron status in RA patients. 95 serum samples were obtained, 70 of them from patients with RA who had visited the department of Rheumatology at Al-Sadder medical city in Najaf governorate （Iraq） and 25 age and sex-matched healthy controls. The authors assessed the clinical parameters of the disease, including ESR （erythrocyte sedimentation rate）, CRP （C-reactive protein）, and RF （rheumatoid factor）. Serum levels of iron and TIBC （total iron binding capacity） were measured spectrophotometrically, while TS% （transferrin saturation percentage） and transferrin concentration were calculated mathematically. Serum concentrations of IL-6 （interleukin-6） and ferritin were measured using an ELISA （enzyme-linked immunosorbent assay）. The results of serum concentration of IL-6 （interleukin-6） and ferritin were significantly elevated （P 〈 0.0001） in patients with RA compared to those of healthy controls. On the other hand, serum concentrations of iron, TIBC （total iron binding capacity）, TS% （transferrin saturation percentage） and transferrin concentration were significantly decreased in patients with RA compared with those of healthy controls. These findings suggest that anemia is the most frequent observations in patients with RA and mostly associative with increasing level of interleukin-6.展开更多
Fortifying commonly consumed foods and beverages offers a great opportunity of filling the nutrient gap between actual and the needed nutrient intakes of young children. Ready-to-drink beverage as a vehicle for fortif...Fortifying commonly consumed foods and beverages offers a great opportunity of filling the nutrient gap between actual and the needed nutrient intakes of young children. Ready-to-drink beverage as a vehicle for fortification is easy to administer, more consistent and least obstructive, because it can be consumed without further processing/cooking. This study aimed to evaluate the effectiveness of fortified beverage on the improving of iron status and school performance test of schoolchildren. About 5,000 schoolchildren aged 6-12 years old from 19 schools in Quirino province, Philippines were invited to participate in the study. Samples of 4,875 children with parental consent were screened for hemoglobin and serum ferritin levels. About 4,495 children had complete participation in the school performance test, which were developed and administered by school supervisors. Children were fed 200 mL ready-to-drink juice fortified with iron, zinc, lysine, vitamins A and C for 120 d. The beverage was delivered through the baseline. At end of the intervention, only 1,050 children had complete data set and the anemia rate reduced from 100% to 60%. Iron deficiency has increased insignificantly from 3.6% to 4.5%. Mean percentage of test scores increased significantly between base and end of the study： English （40% to 60%）, math （35% to 58%） and science （32% to 58%）. In conclusion, consumption of 200 mL fortified juice drink had contributed to the reduction of anemia and increased tests scores of children.展开更多
文摘Iron is a critical micronutrient, and iron derived from heme contributes a large proportion of the total iron absorbed in a typical Western diet. Heme iron is absorbed by different mechanisms than non-heme iron, but despite considerable study over many years these mechanisms remain poorly understood. This review provides an overview of the importance of heme iron in the diet and discusses the two prevailing hypotheses of heme absorption; namely receptor mediated endocytosis of heme, and direct transport into the intestinal enterocyte by recently discovered heme transporters. A specific emphasis is placed on the questions surrounding the site of heme catabolism and the identity of the enzyme that performs this task. Additionally, we present the hypothesis that a non-heme iron transport protein may be required for heme iron absorption and discuss the experiences of our laboratory in examining this hypothesis.
文摘Fe, Chlorophyll (Chl) and total nitrogen (TN) content in tissues were measured in Fe-deficient cultures of Ulva. pertusa over a period of 60 days. Photosynthetic carbon fixation rates were studied at the start of and 30 days after Fe-deficiency culture, when the effects of Fe-deficiency on the ultrastructure were also analyzed. The iron content in tissue decreased exponentially during Fe-deficiency (from 726.7 to 31.6 μg/gdw) and simultaneously Chl and TN content declined to 4.35% and 59.9% of their original levels respectively. Maximum carbon fixation rate (50-250 μmol/m 2 s) under Fe-deficiency decreased significantly compared with the control (p<0.01) and was 13.6 to 0.365 μg C /cm 2 h. Photosynthesis in Fe-deficient cells became light-saturated at lower irradiance than that in control. Ultrastructural observations of Fe-deficient cells showed reductions in chloroplast number, some degeneration of lamellar organization, an increase in vacuolar area, a decrease in mitochondrial matrix density, and variation in accumulation body number and morphology. During Fe-deficiency, the algae growth rate continued to decline and after 6 weeks of iron deficiency, no further growth was detectable. These suggested that the lower growth rate of Ulva. pertusa under Fe-deficiency could be due mainly to nitrogen utilization and inhibition of photosynthesis.
文摘The study was performed to determine whether the srum concentrations of IL （interleukin）-6 are elevated in patients with RA （rheumatoid arthritis） and to investigate the relationship between IL-6 levels and iron status in RA patients. 95 serum samples were obtained, 70 of them from patients with RA who had visited the department of Rheumatology at Al-Sadder medical city in Najaf governorate （Iraq） and 25 age and sex-matched healthy controls. The authors assessed the clinical parameters of the disease, including ESR （erythrocyte sedimentation rate）, CRP （C-reactive protein）, and RF （rheumatoid factor）. Serum levels of iron and TIBC （total iron binding capacity） were measured spectrophotometrically, while TS% （transferrin saturation percentage） and transferrin concentration were calculated mathematically. Serum concentrations of IL-6 （interleukin-6） and ferritin were measured using an ELISA （enzyme-linked immunosorbent assay）. The results of serum concentration of IL-6 （interleukin-6） and ferritin were significantly elevated （P 〈 0.0001） in patients with RA compared to those of healthy controls. On the other hand, serum concentrations of iron, TIBC （total iron binding capacity）, TS% （transferrin saturation percentage） and transferrin concentration were significantly decreased in patients with RA compared with those of healthy controls. These findings suggest that anemia is the most frequent observations in patients with RA and mostly associative with increasing level of interleukin-6.
文摘Fortifying commonly consumed foods and beverages offers a great opportunity of filling the nutrient gap between actual and the needed nutrient intakes of young children. Ready-to-drink beverage as a vehicle for fortification is easy to administer, more consistent and least obstructive, because it can be consumed without further processing/cooking. This study aimed to evaluate the effectiveness of fortified beverage on the improving of iron status and school performance test of schoolchildren. About 5,000 schoolchildren aged 6-12 years old from 19 schools in Quirino province, Philippines were invited to participate in the study. Samples of 4,875 children with parental consent were screened for hemoglobin and serum ferritin levels. About 4,495 children had complete participation in the school performance test, which were developed and administered by school supervisors. Children were fed 200 mL ready-to-drink juice fortified with iron, zinc, lysine, vitamins A and C for 120 d. The beverage was delivered through the baseline. At end of the intervention, only 1,050 children had complete data set and the anemia rate reduced from 100% to 60%. Iron deficiency has increased insignificantly from 3.6% to 4.5%. Mean percentage of test scores increased significantly between base and end of the study： English （40% to 60%）, math （35% to 58%） and science （32% to 58%）. In conclusion, consumption of 200 mL fortified juice drink had contributed to the reduction of anemia and increased tests scores of children.
