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Iron and Heart Failure: Current Concepts and Emerging Pharmacological Paradigms
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作者 Maria Rosaria De Pascale Maria Beatrice Rondinelli +5 位作者 Flora Ascione Vincenzo Maffei Chiara Di Lorenzo Sarah Scagliarini Raffaella Faraonio Antonio Faiella 《World Journal of Cardiovascular Diseases》 CAS 2024年第4期195-216,共22页
Background: Emerging evidence has recognized that anemia and iron deficiency are recurrent comorbidities in chronic heart failure (HF) and several trials have established that iron administration improves myocardial a... Background: Emerging evidence has recognized that anemia and iron deficiency are recurrent comorbidities in chronic heart failure (HF) and several trials have established that iron administration improves myocardial asset and clinical scenario in HF. Purpose: Recent acquisitions suggest that iron deficiency represents a concrete bias in the pathogenetic mechanism of chronic HF, so we have investigated the putative role of the hepcidin/ferroportin axis in the cardiovascular setting to advocate novel pharmacological and clinical approaches. Methods: Here, after an excursus on iron metabolism, we first reviewed the ongoing studies on novel iron targeted compounds. Then, we summarize large clinical interventional studies conducted on patient suffering from iron deficiency and HF which have tested the effects of drugging iron regard QoL, hospitalizations and cardiovascular death. Results: Novel compounds such as hepcidin agonist (PTG 300), synthetic human hepcidin (LJPC-401) and anti FPN (Vamifeport) are ongoing in iron overloaded patients, while the hepcidin blocker (PRS-080) is under investigation in anemic patients. Noteworthy, novel insights could arise from the results of a Phase IV interventional study regarding the modification of hepcidin pathway in a large cohort of HF patients (n = 1992) by sodium glucose cotransporter 2 inhibitors. To date, several studies highlight the beneficial effect of iron administration in cardiovascular setting and latest evidences consider hepcidin level as a novel biomarker of cardiac injury and atherosclerosis. Conclusions: We advocate that data from ongoing studies will suggest novel iron targeted therapies for diagnosis, prognosis and therapy transferable in selected heart failed patients. 展开更多
关键词 Heart Failure iron ANEMIA iron Deficiency HEPCIDIN
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Iron-Deficiency Anemia Management in Gynecological Surgery: A Review of Current Evidence and Best Practices
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作者 Aline Evangelista Santiago Artur Lima Sendin +4 位作者 Víctor Nilo Nogueira Rogério Adão Braga Admilson Lemos Costa Filho Eduardo Batista Cândido Agnaldo Lopes Silva Filho 《Open Journal of Obstetrics and Gynecology》 2024年第8期1223-1241,共19页
Purpose: Due to the high prevalence of iron deficiency anemia in women undergoing gynecological surgeries and its association with worse postoperative results, it is necessary to identify and treat anemia preoperative... Purpose: Due to the high prevalence of iron deficiency anemia in women undergoing gynecological surgeries and its association with worse postoperative results, it is necessary to identify and treat anemia preoperatively. However, although anemia and iron deficiency are significant global health problems, there are still disparities in the recognition and implementation of “Patient Blood Management” (PBM) as a comprehensive approach to mitigating the risks associated with these diseases. The purpose of the study is to review best practices for the treatment of anemia based on the Enhanced Recovery After Surgery (ERAS) protocol and PBM recommendations. Methods: This study reviewed the literature on preoperative iron deficiency anemia in patients undergoing gynecological surgery. We identified references through searches in PubMed using relevant search terms. Results: Among the various strategies used in PBM, perhaps the most important is the early detection and management of anemia. In gynecological surgery, there are several approaches to reducing perioperative blood loss, highlighting the use of gonadotropin-releasing hormone (GnRH) agonists (aGnRh) and antifibrinolytics. Oral and intravenous iron supplementation can be performed in addition to blood transfusion to treat anemia. Conclusion: Addressing preoperative and postoperative anemia through systematic correction, following the guidelines of the ERAS protocol and PBM guidelines, is essential to improving perioperative outcomes in women undergoing gynecological surgery. 展开更多
关键词 ANEMIA Gynecological Surgery iron Supplementation iron Deficiency
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Efficacy and Safety of Iron Isomaltoside Compared with an Oral Iron Supplement in the Management of Patients with Iron Deficiency Anemia
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作者 Zhimin Wu Chunxiao Zhou +4 位作者 Chunyan Wu Qiao Song Shilyu Chen Wen Zhang Shaoling Wu 《Open Journal of Blood Diseases》 2024年第1期17-30,共14页
Objective: To evaluate the treatment outcome of iron isomaltoside compared with an oral iron supplement in the management of iron deficiency anemia (IDA). Methods: The study included patients with IDA who visited the ... Objective: To evaluate the treatment outcome of iron isomaltoside compared with an oral iron supplement in the management of iron deficiency anemia (IDA). Methods: The study included patients with IDA who visited the Outpatient Clinic of the Department of Hematology, the Affiliated Hospital of Qingdao University from October 2021 to August 2022 and met the inclusion and exclusion criteria. According to the actual application of iron supplementation, the patients were divided into two groups: iron isomaltoside treatment group and oral iron treatment group. Baseline measurements were collected before the start of treatment, and measurements were collected subsequently at intervals of 1 week, 1 month, and 3 months. The hematological parameters analyzed included Hemoglobin (Hb), Mean corpuscular hemoglobin (MCH), Mean Hemoglobin content (MCH), Mean corpuscular Hemoglobin concentration (MCHC), and Platelet (Plt). Safety data and adverse event profiles were recorded. Results: Intra-group comparisons: After 1 month of treatment, the Hb significantly improved (P 0.05). Inter-group comparisons: The biochemical parameters were significantly improved (P 0.05) in the iron isomaltoside group compared with those in the oral iron group after 1 month of iron supplementation in patients with mild and moderate anemia. Adverse reactions were tolerable for the patients in both iron isomaltoside group and oral iron group. Only 1 patient in iron isomaltoside group developed anaphylactic shock during medication and recovered after aggressive rescue. Conclusions: Iron isomaltoside which increases Hb more rapidly compared with the oral iron supplementation has few adverse reactions and good acceptance. 展开更多
关键词 ANEMIA iron-DEFICIENCY Drug Therapy iron Isomaltoside 1000 Treatment Outcome
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Iron Status of a People Living with HIV in Sub-Saharan Africa Using a Multi-Criteria Approach Based on the Determination of Blood Ferritin, sTfR, CRP and sTfR-F Index
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作者 Joelle Akissi Koffi Hugues Thierno Ahiboh +4 位作者 Philémond By Delphine Gabillard Affi Roseline Francisk Kouakou Inwoley Andre 《Journal of Biosciences and Medicines》 CAS 2023年第5期239-246,共8页
Background: The assessment of iron status using a single biomarker of iron metabolism is not enough sensitive and specific to reliably diagnose iron deficiency associated with multiple comorbidities. The objective of ... Background: The assessment of iron status using a single biomarker of iron metabolism is not enough sensitive and specific to reliably diagnose iron deficiency associated with multiple comorbidities. The objective of this study was to describe the iron status of people living with HIV in sub-Saharan Africa using a multi-criteria approach based on the determination of blood ferritin, sTfR, CRP and the calculation of sTfR-F index. Methods: This study was conducted using a retrospective panel of 933 sera/plasmas. We determined serum ferritin concentration, serum sTfR concentration, and C-reactive protein (CRP) by immunoturbidimetry for each subject. The sTfR-F index was determined by calculating the sTfR/log ferritin ratio. The statistical test used was Chi<sup>2</sup>. Results: Regardless of the inflammatory syndrome, we determined 3.80%, 30.29%, and 42.70% iron deficiency based on the separate interpretation of ferritin concentration, sTfR, and sTfR-F calculation, respectively. We used those biomarkers in addition to CRP in an algorithm for the diagnosis of iron deficiency. Subjects without inflammatory syndrome, had iron deficiency of 2.89% (n = 26). Taking into account the presence of an inflammatory syndrome, the frequency obtained was n = 88 (9.78%). Overall, iron deficiency was diagnosed in 114 (12.67%) patients when we used the diagnostic algorithm. Conclusion: The use of diagnostic algorithms combining several biomarkers of iron metabolism and taking into account the presence or absence of an inflammatory syndrome is a good approach to detect a large number of iron deficiencies in a population. Therefore, an assessment of the effectiveness of different diagnostic algorithms is necessary. 展开更多
关键词 iron Deficiency iron Metabolism Biomarkers HIV Infection CRP
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Modeling of Fixed Bed Adsorption Column Parameters of Iron(II) Removal Using Ferrihydrite Coated Brick
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作者 Oscar Allahdin Eric Foto +3 位作者 Nicole Poumayé Olga Biteman Joseph Mabingui Michel Wartel 《American Journal of Analytical Chemistry》 CAS 2023年第4期184-201,共18页
Fixed-bed operating experimental column conditions were studied to evaluate the performance of brick from Bangui Region (in Central African Republic), coated with iron oxyhydroxide (ferrihydrite) for the removal of ir... Fixed-bed operating experimental column conditions were studied to evaluate the performance of brick from Bangui Region (in Central African Republic), coated with iron oxyhydroxide (ferrihydrite) for the removal of iron(II) from aqueous solution. The prediction of theoretical breakthrough profiles using Bohart and Adams sorption model was employed to achieve characteristic parameters such as depth of exchange zone, time required for exchange zone to move vertically, moving rate for the exchange zone and adsorption capacity useful for fixed-bed column reactor was investigated under varying operating conditions. The effects of bed depth and flow rate on iron(II) adsorption were studied. Our finding revealed that the Brick from Bangui Region (in Central African Republic), coated with ferrihydrite was a very efficient media for the removal of Fe(II) ions from water. The experimental data showed that the depth and the moving rate (10.3 ± 0.6 cm) and (0.208 ± 0.006 cm/min) respectively of the exchange zone (adsorption zone) were independent of variability of the height of the adsorbent bed column, however the variations of the flow rate affect the moving rate of the exchange zone. The bed depth service time (BDST) model was used and permitted us to predict the service times of columns operated at various flow rates and bed depths and these predicted values were compared with the experimental values. 展开更多
关键词 iron Oxyhydroxide-Coated Brick iron(II)-Adsorption Column Study Break-through Curve BDST
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Treatment of iron deficiency anemia associated with gastrointestinal tract diseases 被引量:13
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作者 Ulas D Bayraktar Soley Bayraktar 《World Journal of Gastroenterology》 SCIE CAS CSCD 2010年第22期2720-2725,共6页
The gastrointestinal (GI) tract is a common site of bleeding that may lead to iron deficiency anemia (IDA). Treatment of IDA depends on severity and acuity of patients’ signs and symptoms. While red blood cell transf... The gastrointestinal (GI) tract is a common site of bleeding that may lead to iron deficiency anemia (IDA). Treatment of IDA depends on severity and acuity of patients’ signs and symptoms. While red blood cell transfusions may be required in hemodynamically unstable patients, transfusions should be avoided in chronically anemic patients due to their potential side effects and cost. Iron studies need to be performed after episodes of GI bleeding and stores need to be replenished before anemia develops. Oral iron preparations are efficacious but poorly tolerated due to non-absorbed iron-mediated GI side effects. However, oral iron dose may be reduced with no effect on its efficacy while decreasing side effects and patient discontinuation rates. Parenteral iron therapy replenishes iron stores quicker and is better tolerated than oral therapy. Serious hypersensitive reactions are very rare with new intravenous preparations. While data on worsening of inflammatory bowel disease (IBD) activity by oral iron therapy are not conclusive, parenteral iron therapy still seems to be advantageous in the treatment of IDA in patients with IBD, because oral iron may not be sufficient to overcome the chronic blood loss and GI side effects of oral iron which may mimic IBD exacerbation. Finally, we believe the choice of oral vs parenteral iron therapy in patients with IBD should primarily depend on acuity and severity of patients’ signs and symptoms. 展开更多
关键词 ANEMIA Inflammatory bowel disease Intravenous iron iron deficiency Oral iron
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Recovery of iron from high phosphorus oolitic iron ore using coal-based reduction followed by magnetic separation 被引量:44
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作者 Yong-sheng Sun Yue-xin Han +2 位作者 Peng Gao Ze-hong Wang Duo-zhen Ren 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2013年第5期411-419,共9页
Oolitic iron ore is one of the most important iron resources. This paper reports the recovery of iron from high phosphorus oolitic iron ore using coal-based reduction and magnetic separation. The influences of reducti... Oolitic iron ore is one of the most important iron resources. This paper reports the recovery of iron from high phosphorus oolitic iron ore using coal-based reduction and magnetic separation. The influences of reduction temperature, reduction time, C/O mole ratio, and CaO content on the metallization degree and iron recovery were investigated in detail. Experimental results show that reduced products with the metallization degree of 95.82% could be produced under the optimal conditions (i.e., reduction temperature, 1250℃; reduction time, 50 min; C/O mole ratio, 2.0; and CaO content, 10wt%). The magnetic concentrate containing 89.63wt% Fe with the iron recovery of 96.21% was obtained. According to the mineralogical and morphologic analysis, the iron minerals had been reduced and iron was mainly enriched into the metallic iron phase embedded in the slag matrix in the form of spherical particles. Apatite was also reduced to phosphorus, which partially migrated into the metallic iron phase. 展开更多
关键词 oolitic iron ore iron ore reduction magnetic separation PHOSPHORUS
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Baicalin interferes with iron accumulation in C6 glioma cells 被引量:4
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作者 Chunyan Guo Xin Chen 《Neural Regeneration Research》 SCIE CAS CSCD 2011年第30期2352-2356,共5页
Baicalin reacts with ferric ammonium citrate and acts as an-iron chelator. The maximal reaction time for baicalin to interact with irons was approximately 3 hours. C6 glioma cell survival decreased following iron-load... Baicalin reacts with ferric ammonium citrate and acts as an-iron chelator. The maximal reaction time for baicalin to interact with irons was approximately 3 hours. C6 glioma cell survival decreased following iron-loading, with a large number of cells accumulating iron. In addition, lipid peroxidation increased. Iron accumulation and lipid peroxidation were the major cause of cellular death. Baicalin and ferric ammonium citrate alleviated iron accumulation in C6 cells and lowered the mortality of nerve cells. In addition, malondialdehyde and lactate dehydrogenase levels reduced. These results indicate that baicalin strongly inhibits lipid peroxidation via chelation, reduces the content of iron in C6 cells, lowers lipid peroxidation, and thus plays a protective role against iron-induced nerve cell death. 展开更多
关键词 BAICALIN iron iron chelation NEUROPROTECTION Parkinson's disease
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Efficacy of Different Iron Fortificants in Wheat Flour in Controlling Iron Deficiency 被引量:3
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作者 JIAN HUANG JING SUN +5 位作者 WEN-XIAN LI LI-JUAN WANG AN-Xu WANG JUN-SHENG HUO JUN-SHI CHEN AND CHUN-MING CHEN 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2009年第2期118-121,共4页
Objective To observe the different impacts of electrolytic iron, FeSO4, and NaFeEDTA on body iron store of anemic school students. Methods Four hundreds anemic students at the age of 11-18 years were divided into four... Objective To observe the different impacts of electrolytic iron, FeSO4, and NaFeEDTA on body iron store of anemic school students. Methods Four hundreds anemic students at the age of 11-18 years were divided into four groups. Of which, three consumed different iron fortificants from wheat flour as food vehicle for six months and one consumed non-fortified flour (control). The fortification level of electrolytic iron, FeSO4, and NaFeEDTA was 60 mg Fe/kg, 30 mg Fe/kg, and 20 mg Fe/kg, respectively. Blood samples were collected at 0, 2, 4, and 6 months and hemoglobin (Hb), serum ferritin (SF), and transferrin receptor (TfR) were measured. Results The hemoglobin levels in three intervention groups increased, the increments of Hb in the NaFeEDTA group were significantly higher than that in the other groups. SF and TfR levels increased in the tested groups and body iron store in the NaFeEDTA group was higher than that in the other groups. These parameters did not show any significant changes in the control group. Conclusion NaFeEDTA and FeSO4 tortified wheat flour has positive impacts on iron status in anemic students and NaFeEDTA is more effective than FeSO4, while electrolytic iron is less effective in improving iron store in anemic students. 展开更多
关键词 Body iron iron deficiency anemia Wheat flour FORTIFICATION Electrolytic iron FESO4 NAFEEDTA
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Is erythroferrone finally the long sought-after systemic erythroid regulator of iron? 被引量:4
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作者 Alfons Lawen 《World Journal of Biological Chemistry》 CAS 2015年第3期78-82,共5页
Iron metabolism is regulated on the cellular and the systemic level. Over the last decade, the liver peptide "hepcidin" has emerged as the body's key irons store regulator. The long postulated "eryt... Iron metabolism is regulated on the cellular and the systemic level. Over the last decade, the liver peptide "hepcidin" has emerged as the body's key irons store regulator. The long postulated "erythroid regulator of iron", however, remained elusive. Last year, evidence was provided, that a previously described myokine "myonectin" may also function as the long sought erythroid regulator of iron. Myonectin was therefore renamed "erythroferrone". This editorial provides a brief discussion on the two functions of erythroferrone and also briefly considers the emerging potential role of transferrin receptor 2 in erythropoiesis. 展开更多
关键词 ERYTHROID REGULATOR of iron HEPCIDIN iron METABOLISM Myonectin SYSTEMIC iron regulation
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Effect of carbon species on the reduction and melting behavior of boron-bearing iron concentrate/carbon composite pellets 被引量:12
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作者 Guang Wang Yin-gui Ding +2 位作者 Jing-song Wang Xue-feng She Qing-guo Xue 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2013年第6期522-528,共7页
Iron nugget and boron-rich slag can be obtained in a short time through high-temperature reduction of boron- bearing iron concentrate by carbonaceous material, both of which are agglomerated together as a carbon compo... Iron nugget and boron-rich slag can be obtained in a short time through high-temperature reduction of boron- bearing iron concentrate by carbonaceous material, both of which are agglomerated together as a carbon composite pellet. This is a novel flow sheet for the comprehensive utilization of boron-bearing iron concentrate to produce a new kind of man-made boron ore. The effect of reducing agent species (i.e., carbon species) on the reduction and melting process of the composite pellet was investigated at a laboratory scale in the present work. The results show that, the reduction rate of the composite pellet increases from bituminite, anthracite, to coke at temperatures ranging from 950 to 1300~C. Reduction temperature has an important effect on the microstructure of reduced pellets. Carbon species also affects the behavior of reduced metallic iron particles. The anthracite-bearing composite pellet melts faster than the bituminite- bearing composite pellet, and the coke-bearing composite pellet cannot melt due to the high fusion point of coke ash. With anthracite as the reducing agent, the recovery rates of iron and boron are 96.5% and 95.7%, respectively. This work can help us get a further understanding of the new process mechanism. 展开更多
关键词 iron ore pellets iron ore reduction BORON bituminite ANTHRACITE COKE
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Iron deficiency anemia in inflammatory bowel disease 被引量:5
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作者 Sindhu Kaitha Muhammad Bashir Tauseef Ali 《World Journal of Gastrointestinal Pathophysiology》 CAS 2015年第3期62-72,共11页
Anemia is a common extraintestinal manifestation of inflammatory bowel disease(IBD) and is frequently overlooked as a complication. Patients with IBD are commonly found to have iron deficiency anemia(IDA) secondary to... Anemia is a common extraintestinal manifestation of inflammatory bowel disease(IBD) and is frequently overlooked as a complication. Patients with IBD are commonly found to have iron deficiency anemia(IDA) secondary to chronic blood loss, and impaired iron absorption due to tissue inflammation. Patients with iron deficiency may not always manifest with signs and symptoms; so, hemoglobin levels in patients with IBD must be regularly monitored for earlier detection of anemia. IDA in IBD is associated with poor quality of life, necessitating prompt diagnosis and appropriate treatment. IDA is often associated with inflammation in patients with IBD. Thus, commonly used labora-tory parameters are inadequate to diagnose IDA, and newer iron indices, such as reticulocyte hemoglobin content or percentage of hypochromic red cells or zinc protoporphyrin, are required to differentiate IDA from anemia of chronic disease. Oral iron preparations are available and are used in patients with mild disease activity. These preparations are inexpensive and con-venient, but can produce gastrointestinal side effects, such as abdominal pain and diarrhea, that limit their use and patient compliance. These preparations are partly absorbed due to inflammation. Non-absorbed iron can be toxic and worsen IBD disease activity. Although cost-effective intravenous iron formulations are widely available and have improved safety profiles, physicians are reluctant to use them. We present a review of the pathophysiologic mechanisms of IDA in IBD, improved diagnostic and therapeutic strategies, efficacy, and safety of iron replacement in IBD. 展开更多
关键词 iron deficiency ANEMIA Inflammatory BOWEL disease HEPCIDIN FERRITIN Oral iron INTRAVENOUS iron
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Helicobacter pylori infection as a cause of iron deficiency anaemia of unknown origin 被引量:13
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作者 Helena Monzón Montserrat Forné +6 位作者 Maria Esteve Mercé Rosinach Carme Loras Jorge C Espinós Josep M Viver Antonio Salas Fernando Fernández-Baares 《World Journal of Gastroenterology》 SCIE CAS 2013年第26期4166-4171,共6页
AIM: To assess the aetiological role of Helicobacter pylori (H. pylori) infection in adult patients with ironrefractory or iron-dependent anaemia of previously unknown origin. METHODS: Consecutive patients with chroni... AIM: To assess the aetiological role of Helicobacter pylori (H. pylori) infection in adult patients with ironrefractory or iron-dependent anaemia of previously unknown origin. METHODS: Consecutive patients with chronic irondeficient anaemia (IDA) with H. pylori infection and a negative standard work-up were prospectively evaluated. All of them had either iron refractoriness or iron dependency. Response to H. pylori eradication was assessed at 6 and 12 mo from follow-up. H. pylori infection was considered to be the cause of the anaemia when a complete anaemia resolution without iron supplements was observed after eradication. RESULTS: H. pylori was eradicated in 88 of the 89 patients. In the non-eradicated patient the four eradicating regimens failed. There were violations of protocol in 4 patients, for whom it was not possible to ascertain the cause of the anaemia. Thus, 84 H. pylori eradicated patients (10 men; 74 women) were available to assess the effect of eradication on IDA. H. pylori infection was considered to be the aetiology of IDA in 32 patients (38.1%; 95%CI: 28.4%-48.8%). This was more frequent in men/postmenopausal women than in premenopausal women (75% vs 23.3%; P < 0.0001) with an OR of 9.8 (95%CI: 3.3-29.6). In these patients, anaemia resolution occurred in the first follow-up visit at 6 mo, and no anaemia or iron deficiency relapse was observed after a mean follow-up of 21 ± 2 mo. CONCLUSION: Gastric H. pylori infection is a frequent cause of iron-refractory or iron-dependent anaemia of previously unknown origin in adult patients. 展开更多
关键词 Helicobacter pylori iron-DEFICIENCY ANAEMIA iron REFRACTORINESS Gluten-sensitive ENTEROPATHY MENOPAUSE
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A study on controlled cooling process for making bainitic ductile iron 被引量:4
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作者 Y.H.Jiang R.Zhou D.H.Lu 《China Foundry》 SCIE CAS 2004年第S1期29-31,共3页
In the present research, TTT curve of bainitic ductile iron under the condition of controlled cooling was generated. The cooling rate of grinding ball and its temperature distribution were also measured at the same ti... In the present research, TTT curve of bainitic ductile iron under the condition of controlled cooling was generated. The cooling rate of grinding ball and its temperature distribution were also measured at the same time. It can be concluded that the bainitic zone of TTT curve is separated from the pearlitic zone. As compared to the water-quenching condition, more even cooling rate and temperature distribution can be achieved in the controlled cooling process. The controlled cooling can keep away from pearlitic zone in the high temperature cooling stage and produce similar results to the process of traditional isothermal cooling with a low cooling rate in the low temperature cooling stage. 展开更多
关键词 controlled cooling grinding ball ductile iron bainitic ductile iron austenite-ferrite ductile iron BAINITE
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Occurrence of the Iron–rich Melt in the Heijianshan Iron Deposit, Eastern Tianshan, NW China: Insights into the Origin of Volcanic Rock–hosted Iron Deposits 被引量:5
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作者 LI Houmin LI Lixing +4 位作者 DING Jianhua LI Yanhe SONG Zhe MENG Jie MA Yubo 《Acta Geologica Sinica(English Edition)》 CAS CSCD 2018年第2期666-681,共16页
Long-standing controversy persists over the presence and role of iron-rich melts in the formation of volcanic rock-hosted iron deposits. Conjugate iron-rich and silica-rich melt inclusions observed in thin-sections ar... Long-standing controversy persists over the presence and role of iron-rich melts in the formation of volcanic rock-hosted iron deposits. Conjugate iron-rich and silica-rich melt inclusions observed in thin-sections are considered as direct evidence for the presence of iron-rich melt, yet unequivocal outcrop-scale evidence of iron-rich melts are still lacking in volcanic rock-hosted iron deposits. Submarine volcanic rock-hosted iron deposits, which are mainly distributed in the western and eastern Tianshan Mountains in Xinjiang, are important resources of iron ores in China, but it remains unclear whether iron-rich melts have played a role in the mineralization of such iron ores. In this study, we observed abundant iron-rich agglomerates in the brecciated andesite lava of the Heijianshan submarine volcanic rock-hosted iron deposit, Eastern Tianshan, China. The iron-rich agglomerates occur as irregular and angular masses filling fractures of the host brecciated andesite lava. They show concentric potassic alteration with silicification or epidotization rims, indicative of their formation after the wall rocks. The iron-rich agglomerates have porphyritic and hyalopilitic textures, and locally display chilled margins in the contact zone with the host rocks. These features cannot be explained by hydrothermal replacement of wall rocks (brecciated andesite lava) which is free of vesicle and amygdale, rather they indicate direct crystallization of the iron-rich agglomerates from iron-rich melts. We propose that the iron-rich agglomerates were formed by open-space filling of volatile-rich iron-rich melt in fractures of the brecciated andesite lava. The iron-rich agglomerates are compositionally similar to the wall-rock brecciated andesite lava, but have much larger variation. Based on mineral assemblages, the iron-rich agglomerates are subdivided into five types, i.e., albite-magnetite type, albite-K-feldspar- magnetite type, K-feldspar-magnetite type, epidote-magnetite type and quartz-magnetite type, representing that products formed at different stages during the evolution of a magmatic-hydrothermal system. The albite-magnetite type represents the earliest crystallization product from a residual iron- rich melt; the albite-K-feldspar-magnetite and K-feldspar-magnetite types show features of magmatic- hydrothermal transition, whereas the epidote-magnetite and quartz-magnetite types represent products of hydrothermal alteration. The occurrence of iron-rich agglomerates provides macroscopic evidence for the presence of iron-rich melts in the mineralization of the Heijianshan iron deposit. It also indicates that iron mineralization of submarine volcanic rock-hosted iron deposits is genetically related to hydrothermal fluids derived from iron-rich melts. 展开更多
关键词 iron-rich agglomerates iron-rich melt volatile submarine volcanic iron deposit Heijianshan Eastern Tianshan
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Effect of iron overload on electrophysiology of slow reaction autorhythmic cells of left ventricular outflow tract in guinea pigs 被引量:4
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作者 Ling Fan Li-Feng Chen +2 位作者 Jing Fan Lan-Ping Zhao Xiao-Yun Zhang 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2018年第2期151-154,共4页
Objective: To investigate the electrophysiology effects and mechanism of iron overload on the slow response autorhythmic cells in the left ventricular outflow tract of guinea pigs.Methods: Standard microelectrode cell... Objective: To investigate the electrophysiology effects and mechanism of iron overload on the slow response autorhythmic cells in the left ventricular outflow tract of guinea pigs.Methods: Standard microelectrode cell recording techniques were adopted to observe the electrophysiological effects of different concentrations of Fe^(2+)(100 μmol/L, 200 μmol/L) on the left ventricular outflow tract autorhythmic cells.Heart tissues were perfused with FeSO_4(200 μmol/L) combing with CaCl_2(4.2 mmol/L), Verapamil,(1 μmol/L), and nickel chloride(200μmol/L) respectively to observe the influences of these contents on electrophysiology of FeSO_4(200μmol/L) on the left ventricular outflow tract autorhythmic cells.Results: Fe^(2+)at both 100 μmol/L and 200 μmol/L could change the electrophysiological parameters of the slow response autorhythmic cells of the left ventricular outflow tract in a concentrationdependent manner resulting into decrease in Vmax, APA and MDP, slower RPF and VDD, and prolonged APD_(50) and APD_(90)(P all <0.05).Besides, perfusion of increased Ca^(2+) concentration could partially offset the electrophysiological effects of Fe^(2+)(200 μmol/L).The L-type calcium channel(LTCC) blocker Verapamil(1 μmol/L) could block the electrophysiological effects of Fe^(2+)(200 μmol/L).But the T-type calcium channel(TTCC) blocker nickel chloride(NiCl_2, 200 μmol/L) could not block the electrophysiological effects of Fe^(2+)(200 μmol/L).Conclusions: Fe^(2+) can directly change the electrophysiological characteristics of the slow response autorhythmic cells of the left ventricular outflow tract probably through the L-type calcium channel. 展开更多
关键词 iron overload iron poisoning Left ventricular outflow tract Slow reaction autorhythmic cell ELECTROPHYSIOLOGY
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New developments and controversies in iron metabolism and iron chelation therapy 被引量:5
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作者 Christina N Kontoghiorghe George J Kontoghiorghes 《World Journal of Methodology》 2016年第1期1-19,共19页
Iron is essential for all organisms including microbial,cancer and human cells. More than a quarter of the human population is affected by abnormalities of iron metabolism, mainly from iron deficiency and iron overloa... Iron is essential for all organisms including microbial,cancer and human cells. More than a quarter of the human population is affected by abnormalities of iron metabolism, mainly from iron deficiency and iron overload. Iron also plays an important role in free radical pathology and oxidative damage which is observed in almost all major diseases, cancer and ageing. New developments include the complete treatment of iron overload and reduction of morbidity and mortality in thalassaemia using deferiprone and selected deferiprone/deferoxamine combinations and also the use of the maltol iron complex in the treatment of iron deficiency anaemia. There is also a prospect of using deferiprone as a universal antioxidant in non iron overloaded diseases such as neurodegenerative, cardiovascular, renal, infectious diseases and cancer. New regulatory molecules of iron metabolism such as endogenous and dietary chelating molecules, hepcidin, mitochondrial ferritin and their role in health and disease is under evaluation. Similarly, new mechanisms of iron deposition, removal, distribution and toxicity have been identified using new techniques such as magnetic resonance imaging increasing our understanding of iron metabolic processes and the targeted treatment of related diseases. The uniform distribution of iron in iron overload between organs and within each organ is no longer valid. Several other controversies such as the toxicity impact of non transferrin bound iron vs injected iron, the excess levels of iron in tissues causing toxicity and the role of chelation on iron absorption need further investigation. Commercial interests of pharmaceutical companies and connections to leading journals are playing a crucial role in shaping worldwide medical opinion on drug sales and use but also patients' therapeutic outcome and safety. Major controversies include the selection criteria and risk/benefit assessment in the use of deferasirox in thalassaemia and more so in idiopathic haemochromatosis, thalassaemia intermedia and ex-thalassaemia transplanted patients who are safely treated with venesection. Iron chelating drugs can override normal regulatory pathways, correct iron imbalance and minimise iron toxicity. The use of iron chelating drugs as main, alternative or adjuvant therapy is in progress in many conditions, especially those with non established or effective therapies. 展开更多
关键词 iron metabolism iron CHELATION therapy DEFERIPRONE DEFEROXAMINE DEFERASIROX iron diseases Medical journals CONTROVERSIES
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An analytical method for Fe(Ⅱ) and Fe(Ⅲ) determination in pharmaceutical grade iron sucrose complex and sodium ferric gluconate complex 被引量:5
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作者 Daniele Merli Antonella Profumo Carlo Dossi 《Journal of Pharmaceutical Analysis》 SCIE CAS 2012年第6期450-453,共4页
A robust voltammetric method has been developed and validated for the determination of Fe(Ⅱ) and Fe(Ⅲ) in pharmaceutical iron polysaccharidic complexes. Undesirable low molecular weight iron complexes, at concen... A robust voltammetric method has been developed and validated for the determination of Fe(Ⅱ) and Fe(Ⅲ) in pharmaceutical iron polysaccharidic complexes. Undesirable low molecular weight iron complexes, at concentration about 3% in the pharmaceutical formulation, can be easily determined with good accuracy and precision. This methodology can be proposed as a viable, environmentally sustainable substitute for the conventional Normal Pulse Polarographic method in US Pharmacopeia, with better analytical figures of merit, and reduced Hg consumption. A deeper insight in Fe(Ⅱ) and Fe(Ⅲ) composition can be gained by the combined use of a new potentiometric technique after chemical decomposition of the complex. 展开更多
关键词 Sodium ferric gluconatecomplex iron sucrose complex iron polysaccharides VOLTAMMETRY
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Effect of microbial mediated iron plaque reduction on arsenic mobility in paddy soil 被引量:11
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作者 WANG Xinjun CHEN Xueping +2 位作者 YANG Jing WANG Zhaosu SUN Guoxin 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2009年第11期1562-1568,共7页
The potential of microbial mediated iron plaque reduction, and associated arsenic (As) mobility were examined by iron reducing bacteria enriched from As contaminated paddy soil. To our knowledge, this is the first t... The potential of microbial mediated iron plaque reduction, and associated arsenic (As) mobility were examined by iron reducing bacteria enriched from As contaminated paddy soil. To our knowledge, this is the first time to report the impact of microbial iron plaque reduction on As mobility. Iron reduction occurred during the inoculation of iron reducing enrichment culture in the treatments with iron plaque and ferrihydrite as the electron acceptors, respectively. The Fe(II) concentration with the treatment of anthraquinone-2, 6-disulfonic acid (AQDS) and iron reducing bacteria increased much faster than the control. Arsenic released from iron plaque with the iron reduction, and a significant correlation between Fe(II) and total As in culture was observed. However, compared with control, the increasing rate of As was inhibited by iron reducing bacteria especially in the presence of AQDS. In addition, the concentrations of As(III) and As(V) in abiotic treatments were higher than those in the biotic treatments at day 30. These results indicated that both microbial and chemical reductions of iron plaque caused As release from iron plaque to aqueous phase, however, microbial iron reduction induced the formation of more crystalline iron minerals, leading to As sequestration. In addition, the presence of AQDS in solution can accelerate the iron reduction, the As release from iron plaque and subsequently the As retention in the crystalline iron mineral. Thus, our results suggested that it is possible to remediate As contaminated soils by utilizing iron reducing bacteria and AQDS. 展开更多
关键词 iron reducing bacteria iron plaque ARSENIC anthraquinone-2 6-disulfonic acid (AQDS) paddy soil FERRIHYDRITE
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Effects of different iron sources on the performance of LiFePO_4/C composite cathode materials 被引量:6
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作者 Fei Gao Zhiyuan Tang Jianjun Xue 《Journal of University of Science and Technology Beijing》 CSCD 2008年第6期802-807,共6页
Olivine LiFePO4/C composite cathode materials were synthesized by a solid state method in N2 + 5vol% H2 atmosphere. The effects of different iron sources, including Fe(OH)3 and FeC2O4·2H2O, on the performance ... Olivine LiFePO4/C composite cathode materials were synthesized by a solid state method in N2 + 5vol% H2 atmosphere. The effects of different iron sources, including Fe(OH)3 and FeC2O4·2H2O, on the performance of as-synthesized cathode materials were investigated and the causes were also analyzed. The crystal structure, the morphology, and the electrochemical performance of the prepared samples were characterized by X-ray diffractometry (XRD), scanning electron microscopy (SEM), laser particle-size distribution measurement, and other electrochemical techniques. The results demonstrate that the LiFePO4/C materials obtained from Fe(OH)3 at 800℃ and FeC2O4·2H2O at 700℃ have the similar electrochemical performances. The initial discharge capacities of LiFePO4/C synthesized from Fe(OH)3 and FeC2O4·2H2O are 134.5 mAh.g^-1 and 137.4 mAh.g^-1 at the C/5 rate, respectively. How- ever, the tap density of the LiFePO4/C materials obtained from Fe(OH)3 are higher, which is significant for the improvement of the capacity of the battery. 展开更多
关键词 iron sources lithium iron phosphate cathode material solid state method
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