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1.
We aimed to investigate the effects of iron deficiency (ID) or iron-deficiency anemia (IDA) on oxidative stress and renal tubular functions before and after treatment of children. A total of 30 children with a diagnosis of IDA constituted the IDA group and 32 children with a diagnosis of ID constituted the ID group. Control group consisted 38 age-matched children. Serum ferritin, soluble transferrin receptor (sTfR), serum, and urinary sodium (Na), potassium (K), calcium (Ca), phosphorus (P), creatinine (Cr), uric acid (UA), urinary N-acetyl-β-d-glucosaminidase (NAG) levels, and intra-erythrocyte malondialdehyde (MDA), catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GSH-Px) levels were measured before and after iron therapy in the IDA and ID groups, whereas it was studied once in the control group. We have divided the study group in groups according to age (infants <2 years, children 3–9 years, and adolescents 10–15 years). Patients with IDA (infant, adolescent) and ID (infant, children, and adolescent) had a significantly high level of MDA in post-treatment period in comparison to those of healthy control. Patients with IDA (children, adolescent) and ID (infant, children) had a significantly high level of pre-treatment GSH-Px than controls. Post-treatment SOD was lower in IDA (children and adolescent) groups than control and post-treatment CAT was lower in IDA and ID (adolescent) groups than control. These findings show that ferrous sulfate used in the treatment of ID or IDA could lead to oxidative stress; however, a marked deterioration of in proximal renal tubular functions was not seen.  相似文献   

2.
Objective Evaluate the safety and efficacy of bovine lactoferrin (bLf) versus the ferrous sulphate standard intervention in curing iron deficiency (ID) and ID anaemia (IDA) in pregnant women affected by hereditary thrombophilia (HT). Design Interventional study. Setting Secondary-level hospital for complicated pregnancies in Rome, Italy. Population 295 HT pregnant women (≥18 years) suffering from ID/IDA. Methods Women were enrolled in Arm A or B in accordance with their personal choice. In Arm A, 156 women received oral administration of 100 mg of bLf twice a day; in Arm B, 139 women received 520 mg of ferrous sulphate once a day. Therapies lasted until delivery. Main outcome measures Red blood cells, haemoglobin, total serum iron, serum ferritin (haematological parameters) were assayed before and every 30 days during therapy until delivery. Serum IL-6, key factor in inflammatory and iron homeostasis disorders, was detected at enrolment and after therapy at delivery. Possible maternal, foetal, and neonatal adverse effects were assessed. Results Haematological parameters were significantly higher in Arm A than in Arm B pregnant women (P ≤ 0.0001). Serum IL-6 significantly decreased in bLf-treated women and increased in ferrous sulphate-treated women. BLf did not exert any adverse effect. Adverse effects in 16.5 % of ferrous sulphate-treated women were recorded. Arm A women experienced no miscarriage compared to five miscarriages in Arm B women. Conclusions Differently from ferrous sulphate, bLf is safe and effective in curing ID/IDA associated with a consistent decrease of serum IL-6. The absence of miscarriage among bLf-treated women provided an unexpected benefit. Trial registration: ClinicalTrials.gov Identifier NCT01221844.  相似文献   

3.
The present study was aimed to determine the effect of iron supplementation on levels of soluble intercellular adhesion molecule-1 (sICAM-1) and soluble vascular cell adhesion molecule-1 (sVCAM-1) in patients with iron deficiency anemia (IDA). In this study, 26 female patients diagnosed with iron deficiency were treated approximately 3 months of oral iron supplementation (99 ± 10 days; ferrous glycine sulfate; 100 mg/day of elemental iron). Levels of sICAM-1 and sVCAM-1 were assessed prior to treatment and after approximately 3 months of treatment and compared with 26 healthy female subjects. A significant increase in sVCAM levels was found in the patients with iron deficiency at the end of the treatment relative to pretreatment levels compared to controls, whereas no significant differences were determined in sICAM levels. In the posttreatment period, no significant change was observed in sICAM levels compared to the pretreatment levels, whereas sVCAM levels decreased. However, after the treatment period, the sVCAM, hemoglobin, mean corpuscular volume (MCV), and serum ferritin levels did not return to the normal range compared to the controls. Pretreatment sVCAM-1 levels were inversely correlated with levels of hemoglobin, hemotocrit, MCV, serum iron, and ferritin. After treatment, the sVCAM-1 levels were negatively correlated with ferritin levels. Levels of sVCAM were significantly higher in patients with IDA than controls. After the treatment period, the sVCAM levels were not completely normalized in patients with IDA compared to controls, regardless of the presence of inadequate levels of hemoglobin, MCV, and serum ferritin. Thus, iron supplementation not only ameliorates anemia, but may also reduce the inflammation markers in cases with IDA.  相似文献   

4.
Iron deficiency anemia (IDA) during pregnancy continues to be of world-wide concern. IDA is a risk factor for preterm delivery and subsequent low birth weight, and possibly for poor neonatal health. Iron supplementation in pregnancy is a widely recommended practice, yet intervention programs have met with many controversies. In our study, 300 women at different trimesters of pregnancy were enrolled in a trial of oral administration of ferrous sulfate (520 mg once a day) or 30% iron-saturated bovine lactoferrin (bLf) (100 mg twice a day). Pregnant women refusing treatment represented the control group. In this group hemoglobin and total serum iron values measured after 30 d without treatment decreased significantly, especially in women at 18-31 weeks of pregnancy. In contrast, after 30 d of oral administration of bLf, hemoglobin and total serum iron values increased and to a greater extent than those observed in women treated orally for 30 d with ferrous sulfate, independently of the trimester of pregnancy. Unlike ferrous sulfate, bLf did not result in any side effects. These findings lead us to hypothesize that lactoferrin could influence iron homeostasis directly or through other proteins involved in iron transport out of the intestinal cells into the blood.  相似文献   

5.
Iron deficiency (ID) and iron deficiency anemia (IDA) are the most common iron disorders throughout the world. ID and IDA, particularly caused by increased iron requirements during pregnancy, represent a high risk for preterm delivery, fetal growth retardation, low birth weight, and inferior neonatal health. Oral administration of ferrous sulfate to cure ID and IDA in pregnancy often fails to increase hematological parameters, causes adverse effects and increases inflammation. Recently, we have demonstrated safety and efficacy of oral administration of 30% iron saturated bovine lactoferrin (bLf) in pregnant women suffering from ID and IDA. Oral administration of bLf significantly increases the number of red blood cells, hemoglobin, total serum iron and serum ferritin already after 30 days of the treatment. The increasing of hematological values by bLf is related to the decrease of serum IL-6 and the increase of serum hepcidin, detected as prohepcidin, whereas ferrous sulfate increases IL-6 and fails to increase hematological parameters and prohepcidin. bLf is a more effective and safer alternative than ferrous sulfate for treating ID and IDA in pregnant women.  相似文献   

6.
Iron deficiency (ID) is the most prevalent micronutrient deficiency disorder in the world. In the developed world, the greatest prevalence of ID and iron deficiency anemia (IDA) occurs in premenopausal women. Premenopausal women experience ID and IDA due to inadequate consumption of dietary iron coupled with iron losses through physiologic processes such as menstruation. Further, female athletes may experience an elevated risk of ID and IDA, as hepcidin, a peptide hormone that inhibits iron absorption and sequesters iron in the macrophage, may rise in response to physical activity. Declines in physical and cognitive performance have been demonstrated in female athletes with ID and IDA. Performance decrements are attenuated as iron status improves. This review will focus on iron status in female athletes, and will include a review of nutritional countermeasures to prevent ID and IDA.  相似文献   

7.
摘要 目的:研究妊娠期缺铁性贫血(IDA)的影响因素及琥珀酸亚铁片的治疗效果。方法:选取2017年5月~2019年6月期间我院收治的妊娠期IDA患者156例作为贫血组,选取同期于我院体检的健康妊娠期志愿者100例作为非贫血组。采用抽签法将贫血组患者分为对照组(常规治疗)和研究组(常规治疗基础上给予琥珀酸亚铁片治疗),各78例,均治疗8周。对比贫血组各亚组患者的疗效、血象指标、铁代谢指标及不良反应发生情况。采用Logistic回归分析妊娠期IDA的影响因素。结果:治疗8周后,研究组的临床总有效率高于对照组(P<0.05)。治疗8周后,研究组的平均血红蛋白量(MCH)、血红蛋白(Hb)、平均红细胞体积(MCV)高于对照组,红细胞体积分布宽度(RDW)低于对照组(P<0.05)。治疗8周后,研究组的血清铁蛋白(SF)、血清铁(SI)高于对照组,血清转铁蛋白受体(sTFR)、总铁结合力(TIBC)低于对照组(P<0.05)。两组的不良反应发生率对比无统计学差异(P>0.05)。单因素分析发现,妊娠期IDA发病与年龄、文化程度、家庭月收入、是否存在不良饮食习惯、是否有慢性胃肠道疾病史、月经初潮年龄、初次性交年龄、初次妊娠年龄、人工流产次数、产次有关(P<0.05),而与体质量指数无关(P>0.05)。Logistic 回归分析结果显示,年龄>30岁、文化程度为初中及以下、存在不良饮食习惯、伴有慢性胃肠道疾病史、月经初潮年龄<13岁、初次妊娠年龄<18岁、人工流产次数>3次是妊娠期 IDA发病的独立危险因素(P<0.05)。结论:引起妊娠期IDA发病的影响因素较多,应针对这些因素进行干预,以降低妊娠期 IDA 的发生率。琥珀酸亚铁片治疗妊娠期IDA,可有效调节铁代谢,改善红细胞形态,缓解贫血症状,且不增加不良反应发生率。  相似文献   

8.
Although a 40 % absorption of a standard reference dose corresponds to iron (Fe) absorption in borderline Fe-deficient subjects, this percentage is currently applied to all subjects independent of Fe status: (a) to assess the use of the 40 % of Fe absorption of the reference dose (FeRD%) for subjects with iron-depleted stores (IDS), normal Fe status (NIS), Fe deficiency without anemia (IDWA), and Fe deficiency anemia (IDA) and (b) to explore relationships between Fe status biomarkers and FeRD%. Six hundred forty-six participants (582 women and 64 men) were selected from multiple Fe bioavailability studies and classified into four groups based on Fe status: NIS, IDS, IDWA, and IDA. All men were classified as normal. The absorption from FeRD% was calculated in each group and correlated with Fe status biomarkers. (a) Women with IDS absorbed 40 (18.9–84.7)?% of the reference dose; (b) for male subjects with NIS, the absorption of the reference dose was 19 (9.8–36.1)?%, while for females, absorption was observed as to be 34 (16.7–68.6)%. In the case of subjects with IDWA, a 43 (19.7–92.5)?% absorption was observed, while subjects with IDA demonstrated 67 (45.2–98.6)?% absorption. Serum ferritin (SF) had the strongest inverse correlation with FeRD% (r?=??0.41, p?<?0.001). A transferrin saturation (TS) <15 % increases the probability that the FeRD% will be highly elevated (OR, 5.05; 95 % CI, 2.73, 9.31; p?<?0.001). A 40 % absorption as reference dose is only appropriate to assess Fe absorption in subjects with IDS and IDWA. SF had an inverse correlation with FeRD%, and TS increases the probability that the FeRD% will be elevated by over fivefold.  相似文献   

9.
Iron-deficiency anemia (IDA) is the most common nutritional deficiency in childhood throughout the world. Although it has been shown that IRA is associated with elevated plasma copper and depleted zinc levels in children, there are conflicting results on the effect of iron supplementation on the absorption of these elements. The aim of this study was to investigate the effects of ferrous and ferric iron supplementation on the trace element status in children (n=25, aged 8-168 mo) with IDA. Fourteen of them were treated with ferric hydroxide-polymaltose complex (Ferrum, Vifor, Switzerland) (6 mg/d in the first 3 mo for initial therapy and 3 mg/kg for 3 mo as maintenance); the others were treated with a ferrous sulfate complex (FerroSanol, Schwarz, Germany) (6 mg/d in the first 3 mo for initial therapy and 3 mg/kg for 3 mo as maintenance). Plasma copper, zinc, and ceruloplasmin levels as well as hematological parameters were determined at baseline and the first, third, and sixth month of the treatment period. The hemoglobin and iron levels of patients in both groups were higher in the first and sixth months compared to baseline. Although the ceruloplasmin levels were depleted (48.9 mg/dL vs 41.4 mg/dL, p=0.035) during ferrous iron treatment, the copper and zinc levels remained unchanged. On the other hand, ferric iron supplementation led to an increase in zinc levels in the sixth month of treatment (0.77 mg/L vs 1.0 mg/L, p=0.021). The plasma copper levels were lower in the ferrous iron-treated group at the end of the first month of treatment than in the ferric irontreated group (1.06 mg/L vs 1.29 mg/L, p=0.008). In conclusion, our data showed that copper and ceruloplasmin metabolisms were affected by ferrous iron supplementation, whereas ferric iron kept them to normal levels of zinc, possibly by affecting their absorption. We conclude that the copper and zinc status of patients with IDA should be taken into consideration before and after iron therapy.  相似文献   

10.
缺铁性贫血是全球最常见的一种营养素缺乏疾病,患者由于血氧不足,易引起疲劳、烦躁、记忆力减退等系列症状,严重影响身 体健康,降低了生活质量。补铁剂是目前最广谱有效的预防和治疗缺铁性贫血的药物。综述补铁剂的发展历程,在铁吸收代谢机制的基础上, 归纳总结传统铁剂的特点和类别,同时对高分子铁剂的结构信息、理化性质、给药途径和剂量、吸收机制等进行系统整理,介绍3 种即 将进入我国市场的新型静脉铁剂的使用和临床试验情况,为补铁剂的研究提供参考。  相似文献   

11.
Iron is a fundamental element for humans as it represents an essential component of many proteins and enzymes. However, this element can also be toxic when present in excess because of its ability to generate reactive oxygen species. This dual nature imposes a tight regulation of iron concentration in the body. In humans, systemic iron homeostasis is mainly regulated at the level of intestinal absorption and, until now, no regulated pathways for the excretion of iron have been found. The regulation and maintenance of systemic iron homeostasis is critical to human health. Excessive iron absorption leads to iron-overload in parenchyma, while low iron absorption leads to plasma iron deficiency, which manifests as hypoferremia (iron deficiency, ID) and ID anaemia (IDA). ID and IDA are still a major health problem in pregnant women. To cure ID and IDA, iron supplements are routinely prescribed. The preferred treatment of ID/IDA, consisting in oral administration of iron as ferrous sulphate, often fails to exert significant effects on hypoferremia and may also cause adverse effects. Lactoferrin (Lf), an iron-binding glycoprotein abundantly found in exocrine secretions of mammals, is emerging as an important regulator of systemic iron homeostasis. Recent data suggest that this natural compound, capable of interacting with the most important components of iron homeostasis, may represent a valuable alternative to iron supplements in the prevention and cure of pregnancy-associated ID and IDA. In this review, recent advances in the molecular circuits involved in the complex cellular and systemic iron homeostasis will be summarised. The role of Lf in curing ID and IDA in pregnancy and in the maintenance of iron homeostasis will also be discussed. Understanding these mechanisms will provide the rationale for the development of novel therapeutic alternatives to ferrous sulphate oral administration in the prevention and cure of ID and IDA.  相似文献   

12.
Iron deficiency without anemia (IDNA), the most prevalent nutritional deficiency worldwide, affects young women of reproductive age. This study aimed to elucidate the relationship between IDNA and mental and somatic symptoms including anger and fatigue using the Japanese version of the Cornell Medical Index Health Questionnaire (CMI–J). Data regarding demographic characteristics, anthropometry, hematological, and biochemical indices of the iron status, frequencies of selected food intakes assessed by self-administered food frequency questionnaires (FFQs), frequencies of nonspecific symptoms, and grades of neurotic tendencies assessed by CMI–J were collected from 76 young women aged 18–22 years living in the metropolitan area of Tokyo, Japan. The subjects were classified as having IDNA (hemoglobin (Hb)?≥?12 g/dL and serum ferritin?<?20 ng/mL; n?=?29), having iron deficiency anemia (IDA) (Hb?<?12 g/dL and serum ferritin?<?20 ng/mL; n?=?10), or having a normal iron status (Hb?≥?12 g/dL and serum ferritin?≥?20 ng/mL; n?=?36). One subject was excluded from the analyses because of Hb?<?12 g/dL and serum ferritin?≥?20 ng/mL. Fisher’s protected least significant difference and the Dwass–Steel–Chritchlow–Fligner multiple comparison tests were used to compare the data of the three groups. P values <0.05 were considered significant. Sections M–R (mental complaints) were significantly higher in the IDNA subjects than in the normal subjects. No significant difference in CMI scores was found between the normal and IDA subjects. Sections I (fatigability), Q (anger), and R (tension) were significantly higher in the IDNA subjects than in the normal subjects, regardless of no significant differences between the normal and IDA subjects in those sections. Young women with IDNA demonstrated a significantly higher proportion of neurotic tendencies (grades II–IV). The intake frequency score of canned or bottled green tea fortified with vitamin C was significantly higher in the IDNA subjects than the IDA subjects. The findings suggest that IDNA may be a risk factor for anger, fatigue, and tension in women of childbearing age.  相似文献   

13.
Iron deficiency (ID) and iron deficiency anemia (IDA) are global public health problems that differentially impact pregnant women and infants in low and middle income countries. IDA during the first 1000 days of life (prenatally through 24 months) has been associated with long term deficits in children's socio-emotional, motor, cognitive, and physiological functioning. Mechanisms linking iron deficiency to children's development may include alterations to dopamine metabolism, myelination, and hippocampal structure and function, as well as maternal depression and unresponsive caregiving, potentially associated with maternal ID. Iron supplementation trials have had mixed success in promoting children's development. Evidence suggests that the most effective interventions to prevent iron deficiency and to promote early child development begin early in life and integrate strategies to ensure adequate iron and nutritional status, along with strategies to promote responsive mother-child interactions and early learning opportunities.  相似文献   

14.
Iron fortification of foods continues to be one of the preferred ways of improving the iron status of the population. Dairy product is a common product in the diet; therefore, it is a plausible vehicle for iron fortification. This study aims to investigate the bioavailability of ferrous gluconate stabilised with glycine (FGSG) in a fresh cheese fortified with zinc. The iron bioavailability of fresh cheese fortified with either FGSG and with or without zinc and FGSG in aqueous solution and a water solution of ferrous ascorbate (reference dose) was studied using double radio iron (55Fe and 59Fe) erythrocyte incorporation in 15 male subjects. All subjects presented with normal values for iron status parameters. The geometric mean of iron bioavailability for the water solution of FGSG was 38.2 %, adjusted to 40 % from reference doses (N.S.). Iron bioavailability in fresh cheese fortified with Ca and Zn was 15.4 % and was 23.1 % without Zn, adjusted to 40 % from reference doses (N.S.). The results of the present study show that the novel iron compound ferrous gluconate stabilised with glycine in a fresh cheese matrix is a good source of iron and can be used in iron fortification programmes.  相似文献   

15.
目的:明确低频正弦波交变电磁场对缺铁性贫血大鼠贫血改善的作用效果,为其未来的临床应用提供实验依据。方法:雄性断乳的SPF级Sprague-Dawley(SD)大鼠,共36只,随机的等分为空白对照组(n=12)、缺铁性贫血组(n=12)和缺铁性贫血+电磁场刺激组(n=12)。缺铁性贫血组和缺铁性贫血+电磁场刺激组的大鼠饲养以低铁饲料和去离子水,每周尾静脉放血1 m L。空白对照组大鼠饲养以常规饲料和普通蒸馏水,且不予尾静脉放血。对缺铁性贫血+电磁场刺激组的12只大鼠施加全身低频交变电磁场刺激,每天刺激2小时,连续刺激10周。实验结束后提取大鼠血液样本,使用氰化高铁血红蛋白法进行测定全血血红蛋白含量,使用专用试剂盒测定血清铁和总铁结合力;提取肝脏和脾脏组织,对肝脏铁和脾脏铁含量进行测定。结果:全身暴露低频交变电磁场刺激显著提高了缺铁性贫血大鼠体重(P0.05),提升了其血清铁含量(P0.05),显著提高全血血红蛋白含量(P0.05),并显著降低了缺铁性贫血大鼠血清总铁结合力(P0.05);同时,电磁刺激也显著提高了缺铁性贫血大鼠肝脏铁和脾脏铁含量(P0.05)。结论:交变电磁场作为一种经济、安全、无创的物理作用方式,具有较为显著的缺铁性贫血的改善效果。  相似文献   

16.

Background

Hepcidin, a key regulator of iron homeostasis, is increased in response to inflammation and some infections, but the in vivo role of hepcidin, particularly in children with iron deficiency anemia (IDA) is unclear. We investigated the relationships between hepcidin, cytokines and iron status in a pediatric population with a high prevalence of both anemia and co-morbid infections.

Methodology/Principal Findings

African refugee children <16 years were consecutively recruited at the initial post-resettlement health check with 181 children meeting inclusion criteria. Data on hematological parameters, cytokine levels and co-morbid infections (Helicobacter pylori, helminth and malaria) were obtained and urinary hepcidin assays performed. The primary outcome measure was urinary hepcidin levels in children with and without iron deficiency (ID) and/or ID anaemia (IDA). The secondary outcome measures included were the relationship between co-morbid infections and (i) ID and IDA, (ii) urinary hepcidin levels and (iii) cytokine levels. IDA was present in 25/181 (13.8%). Children with IDA had significantly lower hepcidin levels (IDA median hepcidin 0.14 nmol/mmol Cr (interquartile range 0.05–0.061) versus non-IDA 2.96 nmol/mmol Cr, (IQR 0.95–6.72), p<0.001). Hemoglobin, log-ferritin, iron, mean cell volume (MCV) and transferrin saturation were positively associated with log-hepcidin levels (log-ferritin beta coefficient (β): 1.30, 95% CI 1.02 to 1.57) and transferrin was inversely associated (β: −0.12, 95% CI −0.15 to −0.08). Cytokine levels (including IL-6) and co-morbid infections were not associated with IDA or hepcidin levels.

Conclusions/Significance

This is the largest pediatric study of the in vivo associations between hepcidin, iron status and cytokines. Gastro-intestinal infections (H. pylori and helminths) did not elevate urinary hepcidin or IL-6 levels in refugee children, nor were they associated with IDA. Longitudinal and mechanistic studies of IDA will further elucidate the role of hepcidin in paediatric iron regulation.  相似文献   

17.

Background

Intermittent iron-folic acid supplementation and regular de-worming are effective initiatives to reduce anemia, iron deficiency, iron deficiency anemia, and soil transmitted helminth infections in women of reproductive age. However, few studies have assessed the long-term effectiveness of population-based interventions delivered in resource-constrained settings.

Methodology/Principal Findings

The objectives were to evaluate the impact of weekly iron-folic acid supplementation and de-worming on mean hemoglobin and the prevalence of anaemia, iron deficiency, and soil transmitted helminth infection in a rural population of women in northern Vietnam and to identify predictive factors for hematological outcomes. A prospective cohort design was used to evaluate a population-based supplementation and deworming program over 54 months. The 389 participants were enrolled just prior to commencement of the intervention. After 54 months 76% (95% CI [68%, 84%]) were taking the iron-folic acid supplement and 95% (95% CI [93%, 98%]) had taken the most recently distributed deworming treatment. Mean hemoglobin rose from 122 g/L (95% CI [120, 124]) to 131 g/L (95% CI [128, 134]) and anemia prevalence fell from 38% (95% CI [31%, 45%]) to 18% (95% CI [12%, 23%]); however, results differed significantly between ethnic groups. Iron deficiency fell from 23% (95% CI [17%, 29%]) to 8% (95% CI [4%, 12%]), while the prevalence of iron deficiency anemia was reduced to 4% (95% CI [1%, 7%]). The prevalence of hookworm infection was reduced from 76% (95% CI [68%, 83%]) to 11% (95% CI [5%, 18%]). The level of moderate or heavy infestation of any soil-transmitted helminth was reduced to less than 1%.

Conclusions/Significance

Population-based interventions can efficiently and effectively reduce anemia and practically eliminate iron deficiency anemia and moderate to heavy soil transmitted helminth infections, maintaining them below the level of public health concern.  相似文献   

18.
Iron (Fe) and zinc’s (Zn) interaction at the absorptive level can have an effect on the success of co-fortification of wheat flour with both minerals on iron deficiency prevention. The aim of the study was to determine the effect of increasing levels of zinc fortificant on the iron absorption of bread co-fortified with iron and zinc consumed with a black tea. Twelve women aged 33–42 years participated in the study. They received on four different days 200 mL of black tea and 100 g of bread made with wheat flour (70 % extraction) fortified with either 30 mg Fe/kg alone, as ferrous sulfate (A), or with the same Fe-fortified flour, but with graded levels of Zn, as zinc sulfate: 30 mg/kg (B), 60 mg/kg (C), or 90 mg/kg (D). Fe radioisotopes (59Fe and 55Fe) of high specific activity were used as tracers, and Fe absorption iron was measured by the incorporation of radioactive Fe into erythrocytes. The geometric mean and range of ±1 SD of Fe absorption were as follows: A?=?6.5 % (2.2–19.3 %), B?=?4.6 % (1.0–21.0 %), C?=?2.1 % (0.9–4.9 %), and D?=?2.2 % (0.7–6.6 %), respectively; ANOVA for repeated measures F?=?10.9, p?<?0.001 (Scheffè’s post hoc test: A vs. C, A vs. D, B vs. C, and B vs. D; p?<?0.05). We can conclude that Fe absorption of bread made from low-extraction flour fortified with 30 mg/kg of Fe, as ferrous sulfate, and co-fortified with zinc, as zinc sulfate consumed with black tea is significantly decreased at a zinc fortification level of ≥60 mg/kg flour.  相似文献   

19.
Microbial oxidation of iron and sulfur are important steps in biogeochemical cycles in mining environments. The aim of this study was the enrichment and identification of two important groups of bacteria that are involved in bioleaching of copper ores. Some soil samples were collected from the Maiduk copper mine. Iron-oxidizing bacteria were enriched in 9K medium containing ferrous sulfate, and sulfur oxidizers were enriched in 9K medium containing powdered sulfur instead of ferrous sulfate as energy source. After three subcultures, autotrophic bacteria were isolated on 9K agarose medium with appropriate energy sources. The autotrophic bacteria from the enrichments were identified by amplification of 16S rRNA gene and sequencing. Bioleaching experiments were performed in 100 ml of 9K medium containing 5 g of low-grade copper ore instead of ferrous sulfate. Twelve different iron and sulfur-oxidizing bacteria were isolated from the collected soil samples of Maiduk copper mine. Molecular identification indicated that two prevalent strains in the ore enrichments could be assigned to the Acidithiobacillus ferooxidans strain HGM and the Thiobacillus thioparus strain HGE. These two strains reached their logarithmic phase of growth after 8 days of incubation in their respective media at 30°C. Of these two cultures, strain HGM leached more copper ore (300 ppm) from the Maiduk copper ore than did strain HGE (200 ppm). Application of these two strains to the Maiduk copper ore in situ and to ore heaps should improve the leaching process.  相似文献   

20.
Our objective was to investigate the effects of iron depletion on adaptation to aerobic exercise, assessed by time to complete a 15-km cycle ergometer test. Forty-two iron-depleted (serum ferritin <16 microg/l), nonanemic (Hb >12 g/dl) women (18-33 yr old) received 100 mg of ferrous sulfate (S) or placebo (P) per day for 6 wk in a randomized, double-blind trial. Subjects trained for 30 min/day, 5 days/wk at 75-85% of maximum heart rate for the final 4 wk of the study. There were no group differences in baseline iron status or in 15-km time. Iron supplementation increased serum ferritin and decreased transferrin receptors in the S compared with the P group. The S and P groups decreased 15-km time and respiratory exchange ratio and increased work rate during the 15-km time trial after training. The decrease in 15-km time was greater in the S than in the P group (P = 0.04) and could be partially attributed to increases in serum ferritin and Hb. These results indicate that iron deficiency without anemia impairs favorable adaptation to aerobic exercise.  相似文献   

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