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1.
Two of the mechanisms for vitamin B(12) deficiency, leading to megaloblastic anemia, are the result of surgically produced abnormalities of the gastrointestinal tract. The basic mechanism is different for each lesion. Total gastrectomy results in complete lack of intrinsic factor which is necessary for vitamin B(12) absorption. It is believed that if patients survive long enough and are not given prophylactic vitamin B(12) therapy, all would develop megaloblastic anemia. Intestinal anastomosis leading to stasis of intestinal contents, with overgrowth of bacteria may cause vitamin B(12) deficiency through bacterial interference with the utilization of vitamin B(12). Use of radioactive vitamin B(12) (cobalt(60)-labeled B(12)) has led to a better understanding of the pathogenesis of both types of megaloblastic anemia. The radioactive vitamin provides a useful tool for study of its absorption from the gastrointestinal tract.  相似文献   

2.
A study was undertaken to ascertain if there were any morphometric or morphologic changes in exfoliated oral squames in either iron-deficiency or vitamin B12-deficiency states. The results revealed a significant (P less than .05) increase in nuclear area and a significant alteration in nuclear/cytoplasmic ratio in vitamin B12 deficiency; both returned to normal following replacement therapy. No changes were seen with iron deficiency anemia or non-vitamin B12 megaloblastic anemia. Ultrastructurally, the surface morphology showed similar features in all groups, with the plasma membrane forming complex folds (microplications) in three patterns: branching, parallel and network. The microplication widths and interplication distances were remarkably constant in both control and study groups, regardless of pattern.  相似文献   

3.
Iron and oxidative stress have a regulatory interplay. During the oxidative burst, phagocytic cells produce free radicals such as hypochlorous acid (HOCl). Nevertheless, scarce studies evaluated the effect of either iron deficiency anemia (IDA) or anemia of chronic disease (ACD) on phagocyte function in the elderly. The aim of the present study was to determine the oxidative burst, phagocytosis, and nitric oxide (?NO) and HOCl, reactive species produced by monocytes and neutrophils in elderly with ACD or IDA. Soluble transferrin receptor, serum ferritin, and soluble transferrin receptor/log ferritin (TfR-F) index determined the iron status. The study was constituted of 39 patients aged over 60 (28 women and 11 men) recruited from the Brazilian Public Health System. Oxidative burst fluorescence intensity per neutrophil in IDA group and HOCl generation in both ACD and IDA groups were found to be lower (p?<?0.05). The percentages of neutrophils and monocytes expressing phagocytosis in ACD group were found to be higher (p?<?0.05). There was an overproduction of ?NO from monocytes, whereas the fundamental generation of HOCl appeared to be lower. Phagocytosis, oxidative burst, and ?NO and HOCl production are involved in iron metabolism regulation in elderly patients with ACD and IDA.  相似文献   

4.
Two of the mechanisms for vitamin B12 deficiency, leading to megaloblastic anemia, are the result of surgically produced abnormalities of the gastrointestinal tract. The basic mechanism is different for each lesion.Total gastrectomy results in complete lack of intrinsic factor which is necessary for vitamin B12 absorption. It is believed that if patients survive long enough and are not given prophylactic vitamin B12 therapy, all would develop megaloblastic anemia.Intestinal anastomosis leading to stasis of intestinal contents, with overgrowth of bacteria may cause vitamin B12 deficiency through bacterial interference with the utilization of vitamin B12.Use of radioactive vitamin B12 (cobalt60-labeled B12) has led to a better understanding of the pathogenesis of both types of megaloblastic anemia. The radioactive vitamin provides a useful tool for study of its absorption from the gastrointestinal tract.  相似文献   

5.
Background. A few cases relating H. pylori infection to iron-deficiency anemia have been described recently. We investigated the role of H. pylori infection in iron-deficiency anemia in preadolescent children and adolescents.
Patients and Methods. We conducted a double-blind, placebo-controlled therapeutic trial in 43 subjects (mean age, 15.4 years) with iron-deficiency anemia. Endoscopy was performed, and biopsy specimens were examined by urease test and histological analysis. Twenty-two of 25 H. pylori –positive patients were assigned randomly to three groups. Group A patients were given oral ferrous sulfate and a 2-week course of bismuth subcitrate, amoxicillin, and metronidazole. Group B patients were given placebo for iron and a 2-week course of triple therapy. Group C patients were given oral ferrous sulfate and a 2-week course of placebo. Iron status was reassessed 4 weeks and 8 weeks after the 2-week regimen ended.
Results. Of the 43 subjects with iron-deficiency anemia, 25 (58.1%) had H. pylori in the antrum. Group A and B subjects, who received eradication therapy, showed a significant increase in hemoglobin level as compared with group C subjects at 8 weeks after therapy ( p = .0086).
Conclusions. Treatment of H. pylori infection was associated with more rapid response to oral iron therapy as compared with the use of iron therapy alone. Such treatment also led to enhanced iron absorption even in those subjects who did not receive oral iron therapy.  相似文献   

6.
This study investigated whether intake of lactoferrin (LF) would improve or prevent anemia in female long distance runners who were training during the summer season and had a high risk of iron-deficiency anemia. Sixteen female long distance runners were divided into a group taking LF and iron (the LF group) and a group that only took iron (the control group) for 8 weeks. In the control group, the ferritin, serum iron, and red blood cell count were significantly lower than before treatment. In the LF group, the hematology data showed no significant change during the 8 weeks. The red blood cell count was significantly higher in the LF group than in the control group. The blood lactate level following a 3,000-m pace run of the control group was also significantly higher than that of the LF group. These observations suggest the possibility that intake of LF increases the absorption and utilization of iron and would be useful in the prevention of iron deficiency anemia among female long distance runners.  相似文献   

7.
Non-anemic women attending a public antenatal clinic were given, daily, a multivitamin tablet containing 78 mg. of elemental iron. The follow-up studies included an analysis of their diets. A total of 311 patients were included, of which one group received a supplement of 0.5 mg. folic acid and 0.005 mg. vitamin B12. The incidence of megaloblastic bone marrow change in the unsupplemented group was 26% and of low blood folates approximately 50%. The incidence of megaloblastic changes was sharply reduced in the supplemented group and the blood folates were elevated to supranormal levels, indicating that the dose of folic acid used may have been above the minimal requirement. Formiminoglutamic acid (FIGLU) excretion could not be correlated with other parameters of folate deficiency. Neutrophil lobe counts did not relate to megaloblastic changes or low folate levels unless there was more than 5% hypersegmentation. The dietary intake was suboptimal in total calories, iron and food folate.  相似文献   

8.
Hereditary hemochromatosis (HHC) is one of the most frequent genetic disorders in humans. In healthy individuals, absorption of iron in the intestine is tightly regulated by cells with the highest iron demand, in particular erythroid precursors. Cloning of intestinal iron transporter proteins provided new insight into mechanisms and regulation of intestinal iron absorption. The aim of this study was to assess whether, in humans, the two transporters are regulated in an iron-dependent manner and whether this regulation is disturbed in HHC. Using quantitative PCR, we measured mRNA expression of divalent cation transporter 1 (DCT1), iron-regulated gene 1 (IREG1), and hephaestin in duodenal biopsy samples of individuals with normal iron levels, iron-deficiency anemia, or iron overload. In controls, we found inverse relationships between the DCT1 splice form containing an iron-responsive element (IRE) and blood hemoglobin, serum transferrin saturation, or ferritin. Subjects with iron-deficiency anemia showed a significant increase in expression of the spliced form, DCT1(IRE) mRNA. Similarly, in subjects homozygous for the C282Y HFE mutation, DCT1(IRE) expression levels remained high despite high serum iron saturation. Furthermore, a significantly increased IREG1 expression was observed. Hephaestin did not exhibit a similar iron-dependent regulation. Our data show that expression levels of human DCT1 mRNA, and to a lesser extent IREG1 mRNA, are regulated in an iron-dependent manner, whereas mRNA of hephaestin is not affected. The lack of appropriate downregulation of apical and basolateral iron transporters in duodenum likely leads to excessive iron absorption in persons with HHC.  相似文献   

9.
While iron deficiency is a common cause of anemia in infants, requiring specific treatment by administration of iron, there are other causes which require treatment equally specific. Anemia due to a nutritional deficiency can be improved only by providing the needed nutriment in sufficient quantity. Two case reports are presented. One is of megaloblastic anemia in an infant, which was treated with a variety of vitamin preparations before administration of folic acid produced improvement. The other report is of anemia due to iron deficiency treated successfully with ferrous sulfate in a dosage twenty times that previously used prophylactically. In prescribing an antianemic preparation the physician should assure himself that the dosage is adequate (for example, 0.5 gm. daily of ferrous sulfate for iron deficiency). "Broad-spectrum" preparations may be lacking in specific hematinics while containing a variety of vitamins which have no specific hematologic value.  相似文献   

10.
BackgroundResearch to date suggests that nickel affects not only the metabolism of vitamin B12 but also folates and thus may affect hematopoiesis processes.ObjectiveThe aim of the study was to examine the relationship of nickel (Ni) status to red blood cell (RBC) parameters and serum vitamin B12, folate and homocysteine concentrations in the course of normal pregnancy and in pregnant women with anemia.MethodsThe study included fifty-three pregnant women recruited to the study from the Lower Silesia region of Poland, 17 % of whom developed anemia. Nickel concentration was determined in urine, whole blood and food samples by atomic absorption spectrometry. At the same time as the food and urine samples were taken, blood was also collected for the determination of RBC parameters and serum vitamin B12, homocysteine and folate concentrations.ResultsThe median reported Ni intake, and the urinary and whole blood nickel contents for the studied pregnant women for the first trimester were respectively – 162.46 μg/day, 3.98 μg/L and 3.32 μg/L; for the second trimester – 110.48 μg/day, 6.86 μg/L and 1.04 μg/L; and for the third trimester – 132.20 μg/day, 3.41 μg/L and 0.70 μg/L. With regard to Ni concentration in whole blood (p = 0.0204) and in urine (p = 0.0003), the differences in the values for individual trimesters were statistically significant. The whole blood Ni level was significantly higher (9.28 vs 3.62 μg/L, p = 0.0114), while the concentration of homosysteine was significantly lower (4.09 vs 5.04 μmol/L, p = 0.0165) in pregnant women with anemia compared to those without anemia. The whole blood Ni concentration was negatively correlated with almost all RBC parameters in non-anemic pregnant women.ConclusionsNi status changes with the development of normal pregnancy, and in the case of anemia, an increase in Ni concentration in whole blood is observed. The demonstrated correlations between the Ni status in pregnant women and RBC parameters as well as serum vitamin B12 and folate concentrations suggest that nickel is associated with the methionine–folate cycle, iron homeostasis and bacterial synthesis of vitamin B12 in humans.  相似文献   

11.
Currently there are no satisfactory methods for estimating dietary iron absorption (bioavailability) at a population level, but this is essential for deriving dietary reference values using the factorial approach. The aim of this work was to develop a novel approach for estimating dietary iron absorption using a population sample from a sub-section of the UK National Diet and Nutrition Survey (NDNS). Data were analyzed in 873 subjects from the 2000–2001 adult cohort of the NDNS, for whom both dietary intake data and hematological measures (hemoglobin and serum ferritin (SF) concentrations) were available. There were 495 men aged 19–64 y (mean age 42.7±12.1 y) and 378 pre-menopausal women (mean age 35.7±8.2 y). Individual dietary iron requirements were estimated using the Institute of Medicine calculations. A full probability approach was then applied to estimate the prevalence of dietary intakes that were insufficient to meet the needs of the men and women separately, based on their estimated daily iron intake and a series of absorption values ranging from 1–40%. The prevalence of SF concentrations below selected cut-off values (indicating that absorption was not high enough to maintain iron stores) was derived from individual SF concentrations. An estimate of dietary iron absorption required to maintain specified SF values was then calculated by matching the observed prevalence of insufficiency with the prevalence predicted for the series of absorption estimates. Mean daily dietary iron intakes were 13.5 mg for men and 9.8 mg for women. Mean calculated dietary absorption was 8% in men (50th percentile for SF 85 µg/L) and 17% in women (50th percentile for SF 38 µg/L). At a ferritin level of 45 µg/L estimated absorption was similar in men (14%) and women (13%). This new method can be used to calculate dietary iron absorption at a population level using data describing total iron intake and SF concentration.  相似文献   

12.
Glycine uptake by erythrocytes from cases of iron deficiency anemia, megaloblastic anemia, and anemia of chronic renal failure and hypothyroidism has been studied. Concentrative uptake, characteristically observed only in iron deficiency, is dependent on a favorable Na+ gradient and is inhibited by p-chloromercuribenzoate. Transport appears to be mediated by a carrier whose possible relation to iron deficiency is discussed.  相似文献   

13.
The aim of this population-based study was to investigate differences in dietary patterns in relation to the level of alcohol consumption among Finnish adults. This study was part of the FinDrink project, an epidemiologic study on alcohol use among Finnish population. It utilized data from the Kuopio Ischaemic Heart Disease Risk Factor Study. A total of 1720 subjects comprising of 816 men and 904 women aged 53-73 years were included in the study in 1998-2001. Food intake was collected via a 4-day food diary method. Self-reported alcohol consumption was assessed with quantity-frequency method based on the Nordic Alcohol Consumption Inventory. Weekly alcohol consumption was categorized into three groups: non-drinkers (<12 grams), moderate drinkers (12-167.9 grams for men, 12-83.9 grams for women) and heavy drinkers (≥ 168 grams for men, ≥ 84 grams for women). Data were analyzed for men and women separately using multiple linear regression models, adjusted for age, occupational status, marital status, smoking, body mass index and leisure time physical activity. In women, moderate/heavy drinkers had lower fibre intake and moderate drinkers had higher vitamin D intake than non-drinkers. Male heavy drinkers had lower fibre, retinol, calcium and iron intake, and moderate/heavy drinkers had higher vitamin D intake than non-drinkers. Fish intake was higher among women moderate drinkers and men moderate/heavy drinkers than non-drinkers. In men, moderate drinkers had lower fruit intake and heavy drinkers had lower milk intake than non-drinkers. Moderate drinkers had higher energy intake from total fats and monosaturated fatty acids than non-drinkers. In contrast, energy intake from carbohydrates was lower among moderate/heavy drinkers than non-drinkers. In conclusion, especially male heavy drinkers had less favorable nutritional intake than moderate and non-drinkers. Further studies on the relationship between alcohol consumption and dietary habits are needed to plan a comprehensive dietary intervention programs in future.  相似文献   

14.
Iron and copper and essential microminerals that are intimately related. The present study was performed to determine the effect of iron-deficiency anemia (IDA) and treatment with iron on laboratory indicators of copper status. Hemoglobin, mean corpuscular volume erythrocyte Zn protoporphyrin, serum ferritin, serum copper, serum ceruloplasmin, and erythrocyte CuZn-superoxide dismutase (SOD) activity were studied in 12 adult women with IDA before and after iron treatment for 60–90 d (100 mg/d Fe, as ferric polymaltose) and in 27 women with normal iron status. Prior to treatment with iron, serum copper and ceruloplasmin were not different between the groups and treatment with iron did not affect these measures. IDA women, before and after treatment with iron, presented a 2.9- and 2-fold decrease in erythrocyte CuZn-SOD activity compared to women with normal iron status (p <0.001). Treatment with iron increased erythrocyte CuZn-SOD activity of the IDA group; however, this change was not statistically significant. in conclusion, CuZn-SOD activity is decreased in IDA. Measurement of this enzyme activity is not useful for evaluating copper nutrition in iron-deficient subjects.  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.
The newer hematinics are merely refinements of preexisting forms of treatment, but they have aided particularly in a better understanding of the deficiency states. The intrinsic factor of Castle has not been isolated from the gastric juice, and the interrelationships of this substance with the extrinsic factor (vitamin B(12)) and folic acid have not been defined at this time. Vitamin B(12) appears to be the active principle of refined liver extract and alone is probably adequate treatment for pernicious anemia. The other varieties of megaloblastic anemia may result from deficiency of vitamin B(12) or folic acid, although generally treatment with the latter brings about complete and lasting remission. The use of multihematinics and multivitamin preparations containing folic acid is to be condemned, particularly because of the possibility of their obscuring anemia and thwarting diagnosis of pernicious anemia until neurologic complications have taken place. Saccharated oxide of iron is a relatively safe preparation for intravenous administration, but the indications for its use are few. Because the body has no mechanism for iron excretion, only the amount of iron necessary to make up a deficiency should be given, although there is no definite evidence that hemochromatosis results from overdosage.  相似文献   

17.
A cohort of rhesus macaques used in neuroscience research was found at routine examinations to have chronic anemia (spun Hct less than 30%). Four anemic (Hct, 24.8% ± 3.4%) and 10 control (39.6% ± 2.9%) macaques were assessed to characterize the anemia and determine probable cause(s); some animals in both groups had cephalic implants. Diagnostic tests included CBC, bone marrow evaluations, iron panels, and serum erythropoietin and hepcidin concentrations. Serum iron and ferritin were 15.8 ± 11.1 μg/dL and 103.8 ± 53.1 ng/mL, respectively, for the anemic group compared with 109.8 ± 23.8 μL/dL and 88.5 ± 41.9 ng/mL, respectively, for the control group. Erythropoietin levels were 16.2 to over 100 mU/mL for the anemic macaques compared with 0 to 1.3 mU/mL for the control group. Hepcidin results were similar in both groups. Because the findings of low iron, high erythropoietin, and normal hepcidin in the anemic macaques supported iron-deficiency anemia or anemia of chronic disease combined with iron-deficiency anemia, a regimen of 4 doses of iron dextran was provided. In treated macaques, Hct rose to 36.3% ± 6.8%, serum iron levels increased to 94.0 ± 41.9 μg/dL, and erythropoietin levels fell to 0.15 to 0.55 mU/mL. Maintenance of normal Hct was variable between macaques and reflected individual ongoing clinical events.  相似文献   

18.
Recent research has shown that constitutional factors can elicit a porotic skeletal lesion pattern related to iron-deficiency anemia, even when adequate dietary iron is available. This study considers the pattern of skeletal involvement under conditions of chronic or endemic dietary stress. Analysis focused on 54 subadults aged 0–10 years at death from the Arroyo Hondo site. Early age of onset is documented in the pattern of coincident active periosteal reactions and porotic lesions under 6 months. Endemically inadequate diets affecting pregnant females and their fetuses, acting synergistically with immediately acquired infections, not weaning diets, are the probable major underlying causes for the early onset of iron-deficiency anemia at Arroyo Hondo.  相似文献   

19.

Background

A micronutrient survey carried out in 2010 among randomly selected Vietnamese women in reproductive age indicated that anemia and micronutrient deficiencies are still prevalent. The objective of this study was thus to analyze the dietary micronutrient intakes of these women, to select the food vehicles to be fortified and to calculate their contributions to meet the recommended nutrient intake (RNI) for iron, zinc, vitamin A and folic acid.

Main Findings

Consumption data showed that the median intake was 38.4% of the RNI for iron, 61.1% for vitamin A and 91.8% for zinc. However, more than 50% of the women had daily zinc consumption below the RNI. Rice and vegetable oil were consumed daily in significant amounts (median: 320.4 g/capita/day and 8.6 g/capita/day respectively) by over 90% of the women, making them suitable vehicles for fortification. Based on consumption data, fortified vegetable oil could contribute to an additional vitamin A intake of 27.1% of the RNI and fortified rice could increase the intake of iron by 41.4% of the RNI, zinc by 15.5% and folate by 34.1%. Other food vehicles, such as fish and soy sauces and flavoring powders, consumed respectively by 63% and 90% of the population could contribute to increase micronutrient intakes if they are properly fortified and promoted. Wheat flower was consumed by 39% of the women and by less than 20% women from the lowest socioeconomic strata.

Conclusion

The fortification of edible vegetable oils with vitamin A and of rice with iron, zinc and folic acid are the most promising fortification strategies to increase micronutrient intakes of women in reproductive age in Vietnam. While rice fortification will be implemented, fortification of fish and soy sauces with iron, that has been proven to be effective, has to be supported and fortification of flavouring powders with micronutrients investigated.  相似文献   

20.
Previous studies revealed novel genetic changes in the duodenal mucosa of iron-deprived rats during postnatal development. These observations are now extended to compare the genetic response to iron deficiency in the duodenum versus jejunum of 12-wk-old rats. cRNA samples were prepared from the duodenal and jejunal mucosa of three groups each of control and iron-deficient rats and hybridized with RAE 230A and 230B gene chips (Affymetrix). Stringent data reduction strategies were employed. Results showed that several genes were similarly induced in both gut segments, including DMT1, Dcytb, transferrin receptor 1, heme oxygenase 1, metallothionein, the Menkes copper ATPase (ATP7A), tripartitie motif protein 27, and the sodium-dependent vitamin C transporter. However, a subset of genes showed regulation in only one or the other gut segment. In duodenum only, gastrokine 1, trefoil factor 1 and claudin 2 were induced by iron-deficiency. Other genes previously identified were only regulated in the duodenum. Overall, these studies demonstrate similarities and distinct differences in the genetic response to iron deprivation in the duodenum versus jejunum and provide evidence that more distal gut segments also may play a role in increasing iron absorption in iron-deficiency anemia.  相似文献   

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