ENVIRONMENTAL RESEARCH BRIEF: THERMOPHYSICAL PROPERTIES OF HFE-125

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Thermophysical properties of HFE-125 (pentafluorodimethylether) suggest that it could serve as an alternative non-ozone depleting refrigerant for certain low temperature applications. This Brief presents the thermophysical properties of HFE-125 (Tables 1-4) which have been obtai...

Differential HFE gene expression is regulated by alternative splicing in human tissues.

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Rute Martins

Full Text Available BACKGROUND: The pathophysiology of HFE-derived Hereditary Hemochromatosis and the function of HFE protein in iron homeostasis remain uncertain. Also, the role of alternative splicing in HFE gene expression regulation and the possible function of the corresponding protein isoforms are still unknown. The aim of this study was to gain insights into the physiological significance of these alternative HFE variants. METHODOLOGY/PRINCIPAL FINDINGS: Alternatively spliced HFE transcripts in diverse human tissues were identified by RT-PCR, cloning and sequencing. Total HFE transcripts, as well as two alternative splicing transcripts were quantified using a real-time PCR methodology. Intracellular localization, trafficking and protein association of GFP-tagged HFE protein variants were analysed in transiently transfected HepG2 cells by immunoprecipitation and immunofluorescence assays. Alternatively spliced HFE transcripts present both level- and tissue-specificity. Concerning the exon 2 skipping and intron 4 inclusion transcripts, the liver presents the lowest relative level, while duodenum presents one of the highest amounts. The protein resulting from exon 2 skipping transcript is unable to associate with β2M and TfR1 and reveals an ER retention. Conversely, the intron 4 inclusion transcript gives rise to a truncated, soluble protein (sHFE that is mostly secreted by cells to the medium in association with β2M. CONCLUSIONS/SIGNIFICANCE: HFE gene post-transcriptional regulation is clearly affected by a tissue-dependent alternative splicing mechanism. Among the corresponding proteins, a sHFE isoform stands out, which upon being secreted into the bloodstream, may act in remote tissues. It could be either an agonist or antagonist of the full length HFE, through hepcidin expression regulation in the liver or by controlling dietary iron absorption in the duodenum.

Influence of HFE variants and cellular iron on monocyte chemoattractant protein-1

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Simmons Zachary

2009-02-01

Full Text Available Abstract Background Polymorphisms in the MHC class 1-like gene known as HFE have been proposed as genetic modifiers of neurodegenerative diseases that include neuroinflammation as part of the disease process. Variants of HFE are relatively common in the general population and are most commonly associated with iron overload, but can promote subclinical cellular iron loading even in the absence of clinically identified disease. The effects of the variants as well as the resulting cellular iron dyshomeostasis potentially impact a number of disease-associated pathways. We tested the hypothesis that the two most common HFE variants, H63D and C282Y, would affect cellular secretion of cytokines and trophic factors. Methods We screened a panel of cytokines and trophic factors using a multiplexed immunoassay in human neuroblastoma SH-SY5Y cells expressing different variants of HFE. The influence of cellular iron secretion on the potent chemokine monocyte chemoattractant protein-1 (MCP-1 was assessed using ferric ammonium citrate and the iron chelator, desferroxamine. Additionally, an antioxidant, Trolox, and an anti-inflammatory, minocycline, were tested for their effects on MCP-1 secretion in the presence of HFE variants. Results Expression of the HFE variants altered the labile iron pool in SH-SY5Y cells. Of the panel of cytokines and trophic factors analyzed, only the release of MCP-1 was affected by the HFE variants. We further examined the relationship between iron and MCP-1 and found MCP-1 secretion tightly associated with intracellular iron status. A potential direct effect of HFE is considered because, despite having similar levels of intracellular iron, the association between HFE genotype and MCP-1 expression was different for the H63D and C282Y HFE variants. Moreover, HFE genotype was a factor in the effect of minocycline, a multifaceted antibiotic used in treating a number of neurologic conditions associated with inflammation, on MCP-1

HFE MUTATIONS AND IRON OVERLOAD IN PATIENTS WITH ALCOHOLIC LIVER DISEASE

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Luis COSTA-MATOS

2013-03-01

Full Text Available Context Alcoholic liver disease (ALD is generally associated with iron overload, which may contribute to its pathogenesis, through increased oxidative stress and cellular damage. There are conflicting reports in literature about hemochromatosis (HFE gene mutations and the severity of liver disease in alcoholic patients. Objectives To compare the prevalence of mutations in the hemochromatosis (HFE gene between patients with ALD and healthy controls; to assess the relation of HFE mutations with liver iron stores and liver disease severity. Methods Liver biopsy specimens were obtained from 63 ALD patients (during routine treatment and 52 healthy controls (during elective cholecystectomy. All individuals underwent routine liver function tests and HFE genotyping (to detect wild-type sequences and C282Y, H63D, S65C, E168Q, E168X, V59M, H63H, P160delC, Q127H, Q283P, V53M and W164X mutations. Associations between HFE mutations and risk of excessive liver iron stores, abnormal serum ferritin, liver fibrosis, or necroinflammatory activity were assessed by multivariate logistic regression analysis. Results ALD patients had significantly higher serum ferritin and transferrin saturation than controls (both P<0.05, but the distribution of HFE mutations was similar between the two groups. For ALD patients, the odds ratio for having at least one HFE mutation and excessive liver iron stores was 17.23 (95% confidence interval (CI: 2.09-142.34, P = 0.008. However, the presence of at least one HFE mutation was not associated with an increased risk of liver fibrosis or necroinflammatory activity. Active alcohol ingestion showed the strongest association to increased serum ferritin (OR = 8.87, 95% CI: 2.11-34.78, P = 0.003. Conclusions ALD patients do not present with a differential profile of HFE mutations from healthy controls. In ALD patients, however, the presence of at least one HFE mutation increases the risk of having excessive liver iron stores but has no

Iron overload in HFE C282Y heterozygotes at first genetic testing: a strategy for identifying rare HFE variants.

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Aguilar-Martinez, Patricia; Grandchamp, Bernard; Cunat, Séverine; Cadet, Estelle; Blanc, François; Nourrit, Marlène; Lassoued, Kaiss; Schved, Jean-François; Rochette, Jacques

2011-04-01

Heterozygotes for the p.Cys282Tyr (C282Y) mutation of the HFE gene do not usually express a hemochromatosis phenotype. Apart from the compound heterozygous state for C282Y and the widespread p.His63Asp (H63D) variant allele, other rare HFE mutations can be found in trans on chromosome 6. We performed molecular investigation of the genes implicated in hereditary hemochromatosis in six patients who presented with iron overload but were simple heterozygotes for the HFE C282Y mutation at first genetic testing. Functional impairment of new variants was deduced from computational methods including molecular modeling studies. We identified four rare HFE mutant alleles, three of which have not been previously described. One mutation is a 13-nucleotide deletion in exon 6 (c.1022_1034del13, p.His341_Ala345 > LeufsX119), which is predicted to lead to an elongated and unstable protein. The second one is a substitution of the last nucleotide of exon 2 (c.340G > A, p.Glu114Lys) which modifies the relative solvent accessibility in a loop interface. The third mutation, p.Arg67Cys, also lies in exon 2 and introduces a destabilization of the secondary structure within a loop of the α1 domain. We also found the previously reported c.548T > C (p.Leu183Pro) missense mutation in exon 3. No other known iron genes were mutated. We present an algorithm at the clinical and genetic levels for identifying patients deserving further investigation. Conclusions Our results suggest that additional mutations in HFE may have a clinical impact in C282Y carriers. In conjunction with results from previously described cases we conclude that an elevated transferrin saturation level and elevated hepatic iron index should indicate the utility of searching for further HFE mutations in C282Y heterozygotes prior to other iron gene studies.

Hemochromatosis (HFE) gene mutations and response to chloroquine in porphyria cutanea tarda.

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Stölzel, Ulrich; Köstler, Erich; Schuppan, Detlef; Richter, Matthias; Wollina, Uwe; Doss, Manfred O; Wittekind, Christian; Tannapfel, Andrea

2003-03-01

To examine the role of hemochromatosis (HFE) gene mutations, which are associated with porphyria cutanea tarda (PCT), in the therapeutic response to chloroquine. We retrospectively analyzed a database (Excel version 2001 [Microsoft Excel, Redmond, Wash]; date range of search, 1985-1999) of chloroquine-treated patients with PCT on whether HFE mutations (C282Y and H63D) might have influenced the clinical response, urinary porphyrin excretion, liver enzyme activities, and serum iron markers. Serum samples and corresponding complete sets of data before and after therapy were available in 62 of 207 patients with PCT who were treated exclusively with chloroquine. Academic teaching hospital. For treatment, low-dose chloroquine diphosphate, 125 to 250 mg twice weekly, was used during a median time of 16 months (range, 12-26 months). Of the 62 German patients with PCT, 37 (60%) carries HFE mutations. Chloroquine therapy was accompanied by clinical remission and reduced urinary porphyrin excretion (P<.001) in the 24 patients (39%) with HFE wild type as well as in 35 HFE heterozygous patients with PCT (56%). Decreases of serum iron markers following chloroquine therapy were limited to patients with PCT and HFE wild type. All patients homozygous for the C282Y mutation (3 [5%] of 62) had high serum iron, ferritin, and transferrin saturation and failed to respond to chloroquine treatment. The therapeutic response to chloroquine was not compromised by C282Y heterozygosity and compound heterozygosity of HFE mutations. Because HFE C282Y homozygotes (+/+) did not respond to chloroquine and a decrease in serum iron concentration was limited to patients with PCT and HFE wild type, phlebotomy should be first-line therapy in patients with PCT and HFE mutations.

HFE Genotyping in Patients with Elevated Serum Iron Indices and Liver Diseases

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Andreia Silva Evangelista

2015-01-01

Full Text Available Iron abnormalities in chronic liver disease may be the result of genetic diseases or secondary factors. The present study aimed to identify subjects with HFE-HH in order to describe the frequency of clinical manifestations, identify risk factors for iron elevation, and compare the iron profile of HFE-HH to other genotypes in liver disease patients. A total of 108 individuals with hepatic disease, transferrin saturation (TS > 45%, and serum ferritin (SF > 350 ng/mL were tested for HFE mutations. Two groups were characterized: C282Y/C282Y or C282Y/H63D genotypes (n=16 were the HFE hereditary hemochromatosis (HFE-HH group; and C282Y and H63D single heterozygotes, the H63D/H63D genotype, and wild-type were considered group 2 (n=92. Nonalcoholic liver disease, alcoholism, and chronic hepatitis C were detected more frequently in group 2, whereas arthropathy, hepatocarcinoma, diabetes, and osteoporosis rates were significantly higher in the HFE-HH group. TS > 82%, SF > 2685 ng/mL, and serum iron > 178 μg/dL were the cutoffs for diagnosis of HFE-HH in patients with liver disease. Thus, in non-Caucasian populations with chronic liver disease, HFE-HH diagnosis is more predictable in those with iron levels higher than those proposed in current guidelines for the general population.

HFE genotype affects exosome phenotype in cancer.

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Mrowczynski, Oliver D; Madhankumar, A B; Slagle-Webb, Becky; Lee, Sang Y; Zacharia, Brad E; Connor, James R

2017-08-01

Neuroblastoma is the third most common childhood cancer, and timely diagnosis and sensitive therapeutic monitoring remain major challenges. Tumor progression and recurrence is common with little understanding of mechanisms. A major recent focus in cancer biology is the impact of exosomes on metastatic behavior and the tumor microenvironment. Exosomes have been demonstrated to contribute to the oncogenic effect on the surrounding tumor environment and also mediate resistance to therapy. The effect of genotype on exosomal phenotype has not yet been explored. We interrogated exosomes from human neuroblastoma cells that express wild-type or mutant forms of the HFE gene. HFE, one of the most common autosomal recessive polymorphisms in the Caucasian population, originally associated with hemochromatosis, has also been associated with increased tumor burden, therapeutic resistance boost, and negative impact on patient survival. Herein, we demonstrate that changes in genotype cause major differences in the molecular and functional properties of exosomes; specifically, HFE mutant derived exosomes have increased expression of proteins relating to invasion, angiogenesis, and cancer therapeutic resistance. HFE mutant derived exosomes were also shown to transfer this cargo to recipient cells and cause an increased oncogenic functionality in those recipient cells. Copyright © 2017. Published by Elsevier B.V.

HFE gene polymorphism defined by sequence-based typing of the Brazilian population and a standardized nomenclature for HFE allele sequences.

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Campos, W N; Massaro, J D; Martinelli, A L C; Halliwell, J A; Marsh, S G E; Mendes-Junior, C T; Donadi, E A

2017-10-01

The HFE molecule controls iron uptake from gut, and defects in the molecule have been associated with iron overload, particularly in hereditary hemochromatosis. The HFE gene including both coding and boundary intronic regions were sequenced in 304 Brazilian individuals, encompassing healthy individuals and patients exhibiting hereditary or acquired iron overload. Six sites of variation were detected: (1) H63D C>G in exon 2, (2) IVS2 (+4) T>C in intron 2, (3) a C>G transversion in intron 3, (4) C282Y G>A in exon 4, (5) IVS4 (-44) T>C in intron 4, and (6) a new guanine deletion (G>del) in intron 5, which were used for haplotype inference. Nine HFE alleles were detected and six of these were officially named on the basis of the HLA Nomenclature, defined by the World Health Organization (WHO) Nomenclature Committee for Factors of the HLA System, and published via the IPD-IMGT/HLA website. Four alleles, HFE*001, *002, *003, and *004 exhibited variation within their exon sequences. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Meta-analyses of HFE variants in coronary heart disease.

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Lian, Jiangfang; Xu, Limin; Huang, Yi; Le, Yanping; Jiang, Danjie; Yang, Xi; Xu, Weifeng; Huang, Xiaoyan; Dong, Changzheng; Ye, Meng; Zhou, Jianqing; Duan, Shiwei

2013-09-15

HFE gene variants can cause hereditary hemochromatosis (HH) that often comes along with an increased risk of coronary heart disease (CHD). The goal of our study is to assess the contribution of four HFE gene variants to the risk of CHD. We conducted four meta-analyses of the studies examining the association between four HFE gene variants and the risk of CHD. A systematic search was conducted using MEDLINE, EMBASE, Web of Science and China National Knowledge Infrastructure (CNKI), Wanfang Chinese Periodical. Meta-analyses showed that HFE rs1799945-G allele was associated with a 6% increased risk of CHD (P=0.02, odds ratio (OR)=1.06, 95% confidence interval (CI)=1.01-1.11). However, no association between the other three HFE gene variants (rs1800562, rs1800730, and rs9366637) and CHD risk was observed by the meta-analyses (all P values>0.05). In addition, the results of our case-control study indicated that rs1800562 and rs1800730 were monomorphic, and that rs1799945 and rs9366637 were not associated with CHD in Han Chinese. Our meta-analysis suggested that a significant association existed between rs1799945 mutation and CHD, although this mutation was rare in Han Chinese. Copyright © 2013 Elsevier B.V. All rights reserved.

Loss of hfe function reverses impaired recognition memory caused by olfactory manganese exposure in mice.

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Ye, Qi; Kim, Jonghan

2015-03-01

Excessive manganese (Mn) in the brain promotes a variety of abnormal behaviors, including memory deficits, decreased motor skills and psychotic behavior resembling Parkinson's disease. Hereditary hemochromatosis (HH) is a prevalent genetic iron overload disorder worldwide. Dysfunction in HFE gene is the major cause of HH. Our previous study has demonstrated that olfactory Mn uptake is altered by HFE deficiency, suggesting that loss of HFE function could alter manganese-associated neurotoxicity. To test this hypothesis, Hfe-knockout (Hfe (-/-)) and wild-type (Hfe (+/+)) mice mice were intranasally-instilled with manganese chloride (MnCl2 5 mg/kg) or water daily for 3 weeks and examined for memory function. Olfactory Mn diminished both short-term recognition and spatial memory in Hfe (+/+) mice, as examined by novel object recognition task and Barnes maze test, respectively. Interestingly, Hfe (-/-) mice did not show impaired recognition memory caused by Mn exposure, suggesting a potential protective effect of Hfe deficiency against Mn-induced memory deficits. Since many of the neurotoxic effects of manganese are thought to result from increased oxidative stress, we quantified activities of anti-oxidant enzymes in the prefrontal cortex (PFC). Mn instillation decreased superoxide dismutase 1 (SOD1) activity in Hfe (+/+) mice, but not in Hfe (-/-) mice. In addition, Hfe deficiency up-regulated SOD1 and glutathione peroxidase activities. These results suggest a beneficial role of Hfe deficiency in attenuating Mn-induced oxidative stress in the PFC. Furthermore, Mn exposure reduced nicotinic acetylcholine receptor levels in the PFC, indicating that blunted acetylcholine signaling could contribute to impaired memory associated with intranasal manganese. Together, our model suggests that disrupted cholinergic system in the brain is involved in airborne Mn-induced memory deficits and loss of HFE function could in part prevent memory loss via a potential up-regulation of

Transgenic HFE-dependent induction of hepcidin in mice does not require transferrin receptor-2.

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Schmidt, Paul J; Fleming, Mark D

2012-06-01

Hereditary hemochomatosis (HH) is caused by mutations in several genes, including HFE and transferrin receptor-2 (TFR2). Loss of either protein decreases expression of the iron regulatory hormone hepcidin by the liver, leading to inappropriately high iron uptake from the diet, and resulting in systemic iron overload. In tissue culture, overexpressed HFE and TFR2 physically interact. Hepatocellular overexpression of Hfe in vivo increases hepcidin expression, despite an associated decrease in Tfr2. On this basis, we hypothesized that Tfr2 would not be required for Hfe-dependent up-regulation of hepcidin. We show that hepatocellular overexpression of Hfe in Tfr2(Y245X/Y245X) mice leads to hepcidin induction eventuating in iron deficiency and a hypochromic, microcytic anemia. Furthermore, coimmunoprecipitation studies using liver lysates did not provide evidence for physical interaction between Hfe and Tfr2 in vivo. In conclusion, we demonstrate that Tfr2 is not essential for Hfe-mediated induction of hepcidin expression, supporting the possibility that TFR2 may regulate iron metabolism in an HFE-independent manner. Copyright © 2012 Wiley Periodicals, Inc.

Identification of novel mutations in HFE, HFE2, TfR2, and SLC40A1 genes in Chinese patients affected by hereditary hemochromatosis.

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Wang, Yongwei; Du, Yali; Liu, Gang; Guo, Shanshan; Hou, Bo; Jiang, Xianyong; Han, Bing; Chang, Yanzhong; Nie, Guangjun

2017-04-01

Hereditary hemochromatosis (HH) is a group of inherited iron-overload disorders associated with pathogenic defects in the genes encoding hemochromatosis (HFE), hemojuvelin (HJV/HFE2), hepcidin (HAMP), transferrin receptor 2 (TfR2), and ferroportin (FPN1/SLC40A1) proteins, and the clinical features are well described. However, there have been only a few detailed reports of HH in Chinese populations. Thus, there is insufficient patient information for population-based analyses in Chinese populations or comparative studies among different ethical groups. In the current work, we describe eight Chinese cases of hereditary hemochromatosis. Gene sequencing results revealed eight mutations (five novel mutations) in HFE, HFE2, TfR2, and SLC40A1 genes in these Chinese HH patients. In addition, we used Polymorphism Phenotyping v2 (Polyphen), Sorting Intolerant From Tolerant (SIFT), and a sequence alignment program to predict the molecular consequences of missense mutations.

HFE gene variants and iron-induced oxygen radical generation in idiopathic pulmonary fibrosis.

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Sangiuolo, Federica; Puxeddu, Ermanno; Pezzuto, Gabriella; Cavalli, Francesco; Longo, Giuliana; Comandini, Alessia; Di Pierro, Donato; Pallante, Marco; Sergiacomi, Gianluigi; Simonetti, Giovanni; Zompatori, Maurizio; Orlandi, Augusto; Magrini, Andrea; Amicosante, Massimo; Mariani, Francesca; Losi, Monica; Fraboni, Daniela; Bisetti, Alberto; Saltini, Cesare

2015-02-01

In idiopathic pulmonary fibrosis (IPF), lung accumulation of excessive extracellular iron and macrophage haemosiderin may suggest disordered iron homeostasis leading to recurring microscopic injury and fibrosing damage. The current study population comprised 89 consistent IPF patients and 107 controls. 54 patients and 11 controls underwent bronchoalveolar lavage (BAL). Haemosiderin was assessed by Perls' stain, BAL fluid malondialdehyde (MDA) by high-performance liquid chromatography, BAL cell iron-dependent oxygen radical generation by fluorimetry and the frequency of hereditary haemochromatosis HFE gene variants by reverse dot blot hybridisation. Macrophage haemosiderin, BAL fluid MDA and BAL cell unstimulated iron-dependent oxygen radical generation were all significantly increased above controls (pHFE allelic variants was markedly higher in IPF compared with controls (40.4% versus 22.4%, OR 2.35, p=0.008) and was associated with higher iron-dependent oxygen radical generation (HFE variant 107.4±56.0, HFE wild type (wt) 59.4±36.4 and controls 16.7±11.8 fluorescence units per 10(5) BAL cells; p=0.028 HFE variant versus HFE wt, p=0.006 HFE wt versus controls). The data suggest iron dysregulation associated with HFE allelic variants may play an important role in increasing susceptibility to environmental exposures, leading to recurring injury and fibrosis in IPF. Copyright ©ERS 2015.

Iron storage disease in Asia-Pacific populations: the importance of non-HFE mutations.

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McDonald, Cameron J; Wallace, Daniel F; Crawford, Darrell H G; Subramaniam, V Nathan

2013-07-01

Hereditary hemochromatosis (HH) is a widely recognized and well-studied condition in European populations. This is largely due to the high prevalence of the C282Y mutation of HFE. Although less common than in Europe, HH cases have been reported in the Asia-Pacific region because of mutations in both HFE and non-HFE genes. Mutations in all of the currently known genes implicated in non-HFE HH (hemojuvelin, hepcidin, transferrin receptor 2, and ferroportin) have been reported in patients from the Asia-Pacific region. This review discusses the molecular basis of HH and the genes and mutations known to cause non-HFE HH with particular reference to the Asia-Pacific region. Challenges in the genetic diagnosis of non-HFE HH are also discussed and how new technologies such as next generation sequencing may be informative in the future. © 2013 Journal of Gastroenterology and Hepatology Foundation and Wiley Publishing Asia Pty Ltd.

Human Factors Engineering (HFE) insights for advanced reactors based upon operating experience

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Higgins, J.; Nasta, K.

1997-01-01

The NRC Human Factors Engineering Program Review Model (HFE PRM, NUREG-0711) was developed to support a design process review for advanced reactor design certification under 10CFR52. The HFE PRM defines ten fundamental elements of a human factors engineering program. An Operating Experience Review (OER) is one of these elements. The main purpose of an OER is to identify potential safety issues from operating plant experience and ensure that they are addressed in a new design. Broad-based experience reviews have typically been performed in the past by reactor designers. For the HFE PRM the intent is to have a more focussed OER that concentrates on HFE issues or experience that would be relevant to the human-system interface (HSI) design process for new advanced reactors. This document provides a detailed list of HFE-relevant operating experience pertinent to the HSI design process for advanced nuclear power plants. This document is intended to be used by NRC reviewers as part of the HFE PRM review process in determining the completeness of an OER performed by an applicant for advanced reactor design certification. 49 refs

C282Y-HFE gene variant affects cholesterol metabolism in human neuroblastoma cells.

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Ali-Rahmani, Fatima; Huang, Michael A; Schengrund, C-L; Connor, James R; Lee, Sang Y

2014-01-01

Although disruptions in the maintenance of iron and cholesterol metabolism have been implicated in several cancers, the association between variants in the HFE gene that is associated with cellular iron uptake and cholesterol metabolism has not been studied. The C282Y-HFE variant is a risk factor for different cancers, is known to affect sphingolipid metabolism, and to result in increased cellular iron uptake. The effect of this variant on cholesterol metabolism and its possible relevance to cancer phenotype was investigated using wild type (WT) and C282Y-HFE transfected human neuroblastoma SH-SY5Y cells. Expression of C282Y-HFE in SH-SY5Y cells resulted in a significant increase in total cholesterol as well as increased transcription of a number of genes involved in its metabolism compared to cells expressing WT-HFE. The marked increase in expression of NPC1L1 relative to that of most other genes, was accompanied by a significant increase in expression of NPC1, a protein that functions in cholesterol uptake by cells. Because inhibitors of cholesterol metabolism have been proposed to be beneficial for treating certain cancers, their effect on the viability of C282Y-HFE neuroblastoma cells was ascertained. C282Y-HFE cells were significantly more sensitive than WT-HFE cells to U18666A, an inhibitor of desmosterol Δ24-reductase the enzyme catalyzing the last step in cholesterol biosynthesis. This was not seen for simvastatin, ezetimibe, or a sphingosine kinase inhibitor. These studies indicate that cancers presenting in carriers of the C282Y-HFE allele might be responsive to treatment designed to selectively reduce cholesterol content in their tumor cells.

The role of HFE genotype in macrophage phenotype.

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Nixon, Anne M; Neely, Elizabeth; Simpson, Ian A; Connor, James R

2018-02-01

Iron regulation is essential for cellular energy production. Loss of cellular iron homeostasis has critical implications for both normal function and disease progression. The H63D variant of the HFE gene is the most common gene variant in Caucasians. The resulting mutant protein alters cellular iron homeostasis and is associated with a number of neurological diseases and cancer. In the brain, microglial and infiltrating macrophages are critical to maintaining iron homeostasis and modulating inflammation associated with the pathogenic process in multiple diseases. This study addresses whether HFE genotype affects macrophage function and the implications of these findings for disease processes. Bone marrow macrophages were isolated from wildtype and H67D HFE knock-in mice. The H67D gene variant in mice is the human equivalent of the H63D variant. Upon differentiation, the macrophages were used to analyze iron regulatory proteins, cellular iron release, migration, phagocytosis, and cytokine expression. The results of this study demonstrate that the H67D HFE genotype significantly impacts a number of critical macrophage functions. Specifically, fundamental activities such as proliferation in response to iron exposure, L-ferritin expression in response to iron loading, secretion of BMP6 and cytokines, and migration and phagocytic activity were all found to be impacted by genotype. Furthermore, we demonstrated that exposure to apo-Tf (iron-poor transferrin) can increase the release of iron from macrophages. In normal conditions, 70% of circulating transferrin is unsaturated. Therefore, the ability of apo-Tf to induce iron release could be a major regulatory mechanism for iron release from macrophages. These studies demonstrate that the HFE genotype impacts fundamental components of macrophage phenotype that could alter their role in degenerative and reparative processes in neurodegenerative disorders.

Tmprss6 is a genetic modifier of the Hfe-hemochromatosis phenotype in mice

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Whittlesey, Rebecca L.; Andrews, Nancy C.

2011-01-01

The hereditary hemochromatosis protein HFE promotes the expression of hepcidin, a circulating hormone produced by the liver that inhibits dietary iron absorption and macrophage iron release. HFE mutations are associated with impaired hepatic bone morphogenetic protein (BMP)/SMAD signaling for hepcidin production. TMPRSS6, a transmembrane serine protease mutated in iron-refractory iron deficiency anemia, inhibits hepcidin expression by dampening BMP/SMAD signaling. In the present study, we used genetic approaches in mice to examine the relationship between Hfe and Tmprss6 in the regulation of systemic iron homeostasis. Heterozygous loss of Tmprss6 in Hfe−/− mice reduced systemic iron overload, whereas homozygous loss caused systemic iron deficiency and elevated hepatic expression of hepcidin and other Bmp/Smad target genes. In contrast, neither genetic loss of Hfe nor hepatic Hfe overexpression modulated the hepcidin elevation and systemic iron deficiency of Tmprss6−/− mice. These results indicate that genetic loss of Tmprss6 increases Bmp/Smad signaling in an Hfe-independent manner that can restore Bmp/Smad signaling in Hfe−/− mice. Furthermore, these results suggest that natural genetic variation in the human ortholog TMPRSS6 might modify the clinical penetrance of HFE-associated hereditary hemochromatosis, raising the possibility that pharmacologic inhibition of TMPRSS6 could attenuate iron loading in this disorder. PMID:21355094

Preliminary investigation of bottlenose dolphins (Tursiops truncatus) for hfe gene-related hemochromatosis.

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Phillips, Brianne E; Venn-Watson, Stephanie; Archer, Linda L; Nollens, Hendrik H; Wellehan, James F X

2014-10-01

Hemochromatosis (iron storage disease) has been reported in diverse mammals including bottlenose dolphins (Tursiops truncatus). The primary cause of excessive iron storage in humans is hereditary hemochromatosis. Most human hereditary hemochromatosis cases (up to 90%) are caused by a point mutation in the hfe gene, resulting in a C282Y substitution leading to iron accumulation. To evaluate the possibility of a hereditary hemochromatosis-like genetic predisposition in dolphins, we sequenced the bottlenose dolphin hfe gene, using reverse transcriptase-PCR and hfe primers designed from the dolphin genome, from liver of affected and healthy control dolphins. Sample size included two case animals and five control animals. Although isotype diversity was evident, no coding differences were identified in the hfe gene between any of the animals examined. Because our sample size was small, we cannot exclude the possibility that hemochromatosis in dolphins is due to a coding mutation in the hfe gene. Other potential causes of hemochromatosis, including mutations in different genes, diet, primary liver disease, and insulin resistance, should be evaluated.

HFE polymorphisms influence the response to chemotherapeutic agents via induction of p16INK4A.

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Lee, Sang Y; Liu, Siying; Mitchell, Ryan M; Slagle-Webb, Becky; Hong, Young-Soo; Sheehan, Jonas M; Connor, James R

2011-11-01

HFE is a protein that impacts cellular iron uptake. HFE gene variants are identified as risk factors or modifiers for multiple diseases. Using HFE stably transfected human neuroblastoma cells, we found that cells carrying the C282Y HFE variant do not differentiate when exposed to retinoic acid. Therefore, we hypothesized HFE variants would impact response to therapeutic agents. Both the human neuroblastoma and glioma cells that express the C282Y HFE variant are resistant to Temodar, geldanamycin and γ-radiation. A gene array analysis revealed that p16INK4A (p16) expression was increased in association with C282Y expression. Decreasing p16 protein by siRNA resulted in increased vulnerability to all of the therapeutic agents suggesting that p16 is responsible for the resistance. Decreasing HFE expression by siRNA resulted in a 85% decrease in p16 expression in the neuroblastoma cells but not the astrocytoma cells. These data suggest a potential direct relationship between HFE and p16 that may be cell specific or mediated by different pathways in the different cell types. In conclusion, the C282Y HFE variant impacts the vulnerability of cancer cells to current treatment strategies apparently by increasing expression of p16. Although best known as a tumor suppressor, there are multiple reports that p16 is elevated in some forms of cancer. Given the frequency of the HFE gene variants, as high as 10% of the Caucasian population, these data provide compelling evidence that the C282Y HFE variant should be part of a pharmacogenetic strategy for evaluating treatment efficacy in cancer cells. Copyright © 2011 UICC.

Effect of Hfe Deficiency on Memory Capacity and Motor Coordination after Manganese Exposure by Drinking Water in Mice.

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Alsulimani, Helal Hussain; Ye, Qi; Kim, Jonghan

2015-12-01

Excess manganese (Mn) is neurotoxic. Increased manganese stores in the brain are associated with a number of behavioral problems, including motor dysfunction, memory loss and psychiatric disorders. We previously showed that the transport and neurotoxicity of manganese after intranasal instillation of the metal are altered in Hfe-deficient mice, a mouse model of the iron overload disorder hereditary hemochromatosis (HH). However, it is not fully understood whether loss of Hfe function modifies Mn neurotoxicity after ingestion. To investigate the role of Hfe in oral Mn toxicity, we exposed Hfe-knockout (Hfe (-/-)) and their control wild-type (Hfe (+/+)) mice to MnCl2 in drinking water (5 mg/mL) for 5 weeks. Motor coordination and spatial memory capacity were determined by the rotarod test and the Barnes maze test, respectively. Brain and liver metal levels were analyzed by inductively coupled plasma mass spectrometry. Compared with the water-drinking group, mice drinking Mn significantly increased Mn concentrations in the liver and brain of both genotypes. Mn exposure decreased iron levels in the liver, but not in the brain. Neither Mn nor Hfe deficiency altered tissue concentrations of copper or zinc. The rotarod test showed that Mn exposure decreased motor skills in Hfe (+/+) mice, but not in Hfe (-/-) mice (p = 0.023). In the Barns maze test, latency to find the target hole was not altered in Mn-exposed Hfe (+/+) compared with water-drinking Hfe (+/+) mice. However, Mn-exposed Hfe (-/-) mice spent more time to find the target hole than Mn-drinking Hfe (+/+) mice (p = 0.028). These data indicate that loss of Hfe function impairs spatial memory upon Mn exposure in drinking water. Our results suggest that individuals with hemochromatosis could be more vulnerable to memory deficits induced by Mn ingestion from our environment. The pathophysiological role of HFE in manganese neurotoxicity should be carefully examined in patients with HFE-associated hemochromatosis and

Alternative Polyadenylation and Nonsense-Mediated Decay Coordinately Regulate the Human HFE mRNA Levels

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Martins, Rute; Proença, Daniela; Silva, Bruno; Barbosa, Cristina; Silva, Ana Luísa; Faustino, Paula; Romão, Luísa

2012-01-01

Nonsense-mediated decay (NMD) is an mRNA surveillance pathway that selectively recognizes and degrades defective mRNAs carrying premature translation-termination codons. However, several studies have shown that NMD also targets physiological transcripts that encode full-length proteins, modulating their expression. Indeed, some features of physiological mRNAs can render them NMD-sensitive. Human HFE is a MHC class I protein mainly expressed in the liver that, when mutated, can cause hereditary hemochromatosis, a common genetic disorder of iron metabolism. The HFE gene structure comprises seven exons; although the sixth exon is 1056 base pairs (bp) long, only the first 41 bp encode for amino acids. Thus, the remaining downstream 1015 bp sequence corresponds to the HFE 3′ untranslated region (UTR), along with exon seven. Therefore, this 3′ UTR encompasses an exon/exon junction, a feature that can make the corresponding physiological transcript NMD-sensitive. Here, we demonstrate that in UPF1-depleted or in cycloheximide-treated HeLa and HepG2 cells the HFE transcripts are clearly upregulated, meaning that the physiological HFE mRNA is in fact an NMD-target. This role of NMD in controlling the HFE expression levels was further confirmed in HeLa cells transiently expressing the HFE human gene. Besides, we show, by 3′-RACE analysis in several human tissues that HFE mRNA expression results from alternative cleavage and polyadenylation at four different sites – two were previously described and two are novel polyadenylation sites: one located at exon six, which confers NMD-resistance to the corresponding transcripts, and another located at exon seven. In addition, we show that the amount of HFE mRNA isoforms resulting from cleavage and polyadenylation at exon seven, although present in both cell lines, is higher in HepG2 cells. These results reveal that NMD and alternative polyadenylation may act coordinately to control HFE mRNA levels, possibly varying its

Factors affecting the appreciation generated through applying human factors/ergonomics (HFE) principles to systems of work.

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So, R H Y; Lam, S T

2014-01-01

This retrospective study examined the levels of appreciation (applause) given by clients to Human Factors/Ergonomic (HFE) specialists after they have modified the systems of work. Thirteen non-academic projects were chosen because the HFE interventions involved changed the way workers work at their workplaces. Companies involved range from multi-national corporations and military organizations with thousands of employees to small trading companies with less than 10 employees. In 5 cases the HFE recommendations were fully adopted and well appreciated. In 4 they were largely ignored and not appreciated, with partial adoption and some appreciation in the other 4 cases. Three factors that predict appreciation were identified: (i) alignment between the benefits HFE can provide and the project's key performance indices; (ii) awareness of HFE among the client's senior management; and (iii) a team organization appropriate for applying HFE recommendations. Having an HFE specialist on the client's side can greatly increase levels of appreciation, but lack of such a specialist will not affect levels of appreciation. A clear contractual requirement for HFE intervention does not promote appreciation significantly, but its absence can greatly reduce levels of appreciation. These relationships are discussed using the Kano's model of quality. Means to generate greater appreciation of the benefits of HFE are discussed. Copyright © 2013 Elsevier Ltd and The Ergonomics Society. All rights reserved.

Trends in HFE Methods and Tools and Their Applicability to Safety Reviews

Energy Technology Data Exchange (ETDEWEB)

O' Hara, J.M.; Plott, C.; Milanski, J.; Ronan, A.; Scheff, S.; Laux, L.; and Bzostek, J.

2009-09-30

The U.S. Nuclear Regulatory Commission's (NRC) conducts human factors engineering (HFE) safety reviews of applicant submittals for new plants and for changes to existing plants. The reviews include the evaluation of the methods and tools (M&T) used by applicants as part of their HFE program. The technology used to perform HFE activities has been rapidly evolving, resulting in a whole new generation of HFE M&Ts. The objectives of this research were to identify the current trends in HFE methods and tools, determine their applicability to NRC safety reviews, and identify topics for which the NRC may need additional guidance to support the NRC's safety reviews. We conducted a survey that identified over 100 new HFE M&Ts. The M&Ts were assessed to identify general trends. Seven trends were identified: Computer Applications for Performing Traditional Analyses, Computer-Aided Design, Integration of HFE Methods and Tools, Rapid Development Engineering, Analysis of Cognitive Tasks, Use of Virtual Environments and Visualizations, and Application of Human Performance Models. We assessed each trend to determine its applicability to the NRC's review by considering (1) whether the nuclear industry is making use of M&Ts for each trend, and (2) whether M&Ts reflecting the trend can be reviewed using the current design review guidance. We concluded that M&T trends that are applicable to the commercial nuclear industry and are expected to impact safety reviews may be considered for review guidance development. Three trends fell into this category: Analysis of Cognitive Tasks, Use of Virtual Environments and Visualizations, and Application of Human Performance Models. The other trends do not need to be addressed at this time.

Trends in HFE Methods and Tools and Their Applicability to Safety Reviews

International Nuclear Information System (INIS)

O'Hara, J.M.; Plott, C.; Milanski, J.; Ronan, A.; Scheff, S.; Laux, L.; Bzostek, J.

2009-01-01

The U.S. Nuclear Regulatory Commission's (NRC) conducts human factors engineering (HFE) safety reviews of applicant submittals for new plants and for changes to existing plants. The reviews include the evaluation of the methods and tools (M and T) used by applicants as part of their HFE program. The technology used to perform HFE activities has been rapidly evolving, resulting in a whole new generation of HFE M and Ts. The objectives of this research were to identify the current trends in HFE methods and tools, determine their applicability to NRC safety reviews, and identify topics for which the NRC may need additional guidance to support the NRC's safety reviews. We conducted a survey that identified over 100 new HFE M and Ts. The M and Ts were assessed to identify general trends. Seven trends were identified: Computer Applications for Performing Traditional Analyses, Computer-Aided Design, Integration of HFE Methods and Tools, Rapid Development Engineering, Analysis of Cognitive Tasks, Use of Virtual Environments and Visualizations, and Application of Human Performance Models. We assessed each trend to determine its applicability to the NRC's review by considering (1) whether the nuclear industry is making use of M and Ts for each trend, and (2) whether M and Ts reflecting the trend can be reviewed using the current design review guidance. We concluded that M and T trends that are applicable to the commercial nuclear industry and are expected to impact safety reviews may be considered for review guidance development. Three trends fell into this category: Analysis of Cognitive Tasks, Use of Virtual Environments and Visualizations, and Application of Human Performance Models. The other trends do not need to be addressed at this time.

HFE mRNA expression is responsive to intracellular and extracellular iron loading: short communication.

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Mehta, Kosha J; Farnaud, Sebastien; Patel, Vinood B

2017-10-01

In liver hepatocytes, the HFE gene regulates cellular and systemic iron homeostasis by modulating cellular iron-uptake and producing the iron-hormone hepcidin in response to systemic iron elevation. However, the mechanism of iron-sensing in hepatocytes remain enigmatic. Therefore, to study the effect of iron on HFE and hepcidin (HAMP) expressions under distinct extracellular and intracellular iron-loading, we examined the effect of holotransferrin treatment (1, 2, 5 and 8 g/L for 6 h) on intracellular iron levels, and mRNA expressions of HFE and HAMP in wild-type HepG2 and previously characterized iron-loaded recombinant-TfR1 HepG2 cells. Gene expression was analyzed by real-time PCR and intracellular iron was measured by ferrozine assay. Data showed that in the wild-type cells, where intracellular iron content remained unchanged, HFE expression remained unaltered at low holotransferrin treatments but was upregulated upon 5 g/L (p HFE and HAMP expressions were elevated only at low 1 g/L treatment (p HFE (p HFE mRNA was independently elevated by extracellular and intracellular iron-excess. Thus, it may be involved in sensing both, extracellular and intracellular iron. Repression of HAMP expression under simultaneous intracellular and extracellular iron-loading resembles non-hereditary iron-excess pathologies.

Pathophysiological consequences and benefits of HFE mutations: 20 years of research

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Hollerer, Ina; Bachmann, André; Muckenthaler, Martina U.

2017-01-01

Mutations in the HFE (hemochromatosis) gene cause hereditary hemochromatosis, an iron overload disorder that is hallmarked by excessive accumulation of iron in parenchymal organs. The HFE mutation p.Cys282Tyr is pathologically most relevant and occurs in the Caucasian population with a carrier frequency of up to 1 in 8 in specific European regions. Despite this high prevalence, the mutation causes a clinically relevant phenotype only in a minority of cases. In this review, we summarize historical facts and recent research findings about hereditary hemochromatosis, and outline the pathological consequences of the associated gene defects. In addition, we discuss potential advantages of HFE mutations in asymptomatic carriers. PMID:28280078

Hemochromatosis (HFE gene mutations in Brazilian chronic hemodialysis patients

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F.V. Perícole

2005-09-01

Full Text Available Patients with chronic renal insufficiency (CRI have reduced hemoglobin levels, mostly as a result of decreased kidney production of erythropoietin, but the relation between renal insufficiency and the magnitude of hemoglobin reduction has not been well defined. Hereditary hemochromatosis is an inherited disorder of iron metabolism. The importance of the association of hemochromatosis with treatment for anemia among patients with CRI has not been well described. We analyzed the frequency of the C282Y and H63D mutations in the HFE gene in 201 Brazilian individuals with CRI undergoing hemodialysis. The analysis of the effects of HFE mutations on iron metabolism and anemia with biochemical parameters was possible in 118 patients of this study (hemoglobin, hematocrit, ferritin levels, transferrin saturation, and serum iron. A C282Y heterozygous mutation was found in 7/201 (3.4% and H63D homozygous and heterozygous mutation were found in 2/201 (1.0% and 46/201 (22.9%, respectively. The allelic frequencies of the HFE mutations (0.017 for C282Y mutation and 0.124 for H63D mutation did not differ between patients with CRI and healthy controls. Regarding the biochemical parameters, no differences were observed between HFE heterozygous and mutation-negative patients, although ferritin levels were not higher among patients with the H63D mutation (P = 0.08. From what we observed in our study, C282Y/H63D HFE gene mutations are not related to degrees of anemia or iron stores in CRI patients receiving intravenous iron supplementation (P > 0.10. Nevertheless, the present data suggest that the H63D mutation may have an important function as a modulating factor of iron overload in these patients.

HFE Gene Mutations and Iron Status in 100 Healthy Polish Children.

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Kaczorowska-Hac, Barbara; Luszczyk, Marcin; Antosiewicz, Jedrzej; Ziolkowski, Wieslaw; Adamkiewicz-Drozynska, Elzbieta; Mysliwiec, Malgorzata; Milosz, Ewa; Kaczor, Jan J

2017-07-01

Iron participates in oxygen transport, energetic, metabolic, and immunologic processes. There are 2 main causes of iron overload: hereditary hemochromatosis which is a primary cause, is a metabolic disorder caused by mutations of genes that control iron metabolism and secondary hemochromatosis caused by multitransfusions, chronic hemolysis, and intake of iron rich food. The most common type of hereditary hemochromatosis is caused by HFE gene mutation. In this study, we analyzed iron metabolism in 100 healthy Polish children in relation to their HFE gene status. The wild-type HFE gene was predominant being observed in 60 children (60%). Twenty-five children (25%), presented with heterozygotic H63D mutation, and 15 children (15%), presented with other mutations (heterozygotic C282Y and S65C mutation, compound heterozygotes C282Y/S65C, C282Y/H63D, H63D homozygote). The mean concentration of iron, the level of ferritin, and transferrin saturation were statistically higher in the group of HFE variants compared with the wild-type group. H63D carriers presented with higher mean concentration of iron, ferritin levels, and transferrin saturation compared with the wild-type group. Male HFE carriers presented with higher iron concentration, transferrin saturation, and ferritin levels than females. This preliminary investigation demonstrates allelic impact on potential disease progression from childhood.

HFE Genotype Restricts the Response to Paraquat in a Mouse Model of Neurotoxicity.

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Nixon, Anne M; Meadowcroft, Mark D; Neely, Elizabeth B; Snyder, Amanda M; Purnell, Carson J; Wright, Justin; Lamendella, Regina; Nandar, Wint; Huang, Xuemei; Connor, James R

2018-05-01

Parkinson's disease is marked clinically by motor dysfunction and pathologically by dopaminergic cell loss in the substantia nigra and iron accumulation in the substantia nigra. The driver underlying iron accumulation remains unknown and could be genetic or environmental. The HFE protein is critical for the regulation of cellular iron uptake. Mutations within this protein are associated with increased iron accumulation including in the brain. We have focused on the commonly occurring H63D variant of the HFE gene as a disease modifier in a number of neurodegenerative diseases. To investigate the role of H63D HFE genotype, we generated a mouse model in which the wild-type (WT) HFE gene is replaced by the H67D gene variant (mouse homolog of the human H63D gene variant). Using paraquat toxicity as the model for Parkinson's disease, we found that WT mice responded as expected with significantly greater motor function, loss of tyrosine hydroxylase staining and increase microglial staining in the substantia nigra, and an increase in R 2 relaxation rate within the substantia nigra of the paraquat-treated mice compared to their saline-treated counterparts. In contrast, the H67D mice showed a remarkable resistance to paraquat treatment; specifically differing from the WT mice with no changes in motor function or changes in R 2 relaxation rates following paraquat exposure. At baseline, there were differences between the H67D HFE mice and WT mice in gut microbiome profile and increased L-ferritin staining in the substantia nigra that could account for the resistance to paraquat. Of particular note, the H67D HFE mice regardless of whether or not they were treated with paraquat had significantly less tyrosine hydroxylase immunostaining than WT. Our results clearly demonstrate that the HFE genotype impacts the expression of tyrosine hydroxylase in the substantia nigra, the gut microbiome and the response to paraquat providing additional support that the HFE genotype is a disease

HFE gene mutation is a risk factor for tissue iron accumulation in hemodialysis patients.

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Turkmen, Ercan; Yildirim, Tolga; Yilmaz, Rahmi; Hazirolan, Tuncay; Eldem, Gonca; Yilmaz, Engin; Aybal Kutlugun, Aysun; Altindal, Mahmut; Altun, Bulent

2017-07-01

HFE gene mutations are responsible from iron overload in general population. Studies in hemodialysis patients investigated the effect of presence of HFE gene mutations on serum ferritin and transferrin saturation (TSAT) with conflicting results. However effect of HFE mutations on iron overload in hemodialysis patients was not previously extensively studied. 36 hemodialysis patients (age 51.3 ± 15.6, (18/18) male/female) and 44 healthy control subjects included in this cross sectional study. Hemoglobin, ferritin, TSAT in the preceding 2 years were recorded. Iron and erythropoietin (EPO) administered during this period were calculated. Iron accumulation in heart and liver was detected by MRI. Relationship between HFE gene mutation, hemoglobin, iron parameters and EPO doses, and tissue iron accumulation were determined. Iron overload was detected in nine (25%) patients. Hemoglobin, iron parameters, weekly EPO doses, and monthly iron doses of patients with and without iron overload were similar. There was no difference between control group and hemodialysis patients with respect to the prevalence of HFE gene mutations. Iron overload was detected in five of eight patients who had HFE gene mutations, but iron overload was present in 4 of 28 patients who had no mutations (P = 0.01). Hemoglobin, iron parameters, erythropoietin, and iron doses were similar in patients with and without gene mutations. HFE gene mutations remained the main determinant of iron overload after multivariate logistic regression analysis (P = 0.02; OR, 11.6). Serum iron parameters were not adequate to detect iron overload and HFE gene mutation was found to be an important risk factor for iron accumulation. © 2017 International Society for Hemodialysis.

Iron overload and HFE gene mutations in Polish patients with liver cirrhosis.

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Sikorska, Katarzyna; Romanowski, Tomasz; Stalke, Piotr; Iżycka-Świeszewska, Ewa; Bielawski, Krzysztof Piotr

2011-06-01

Increased liver iron stores may contribute to the progression of liver injury and fibrosis, and are associated with a higher risk of hepatocellular carcinoma development. Pre-transplant symptoms of iron overload in patients with liver cirrhosis are associated with higher risk of infectious and malignant complications in liver transplant recipients. HFE gene mutations may be involved in the pathogenesis of liver iron overload and influence the progression of chronic liver diseases of different origins. This study was designed to determine the prevalence of iron overload in relation to HFE gene mutations among Polish patients with liver cirrhosis. Sixty-one patients with liver cirrhosis included in the study were compared with a control group of 42 consecutive patients subjected to liver biopsy because of chronic liver diseases. Liver function tests and serum iron markers were assessed in both groups. All patients were screened for HFE mutations (C282Y, H63D, S65C). Thirty-six of 61 patients from the study group and all controls had liver biopsy performed with semiquantitative assessment of iron deposits in hepatocytes. The biochemical markers of iron overload and iron deposits in the liver were detected with a higher frequency (70% and 47% respectively) in patients with liver cirrhosis. There were no differences in the prevalence of all HFE mutations in both groups. In patients with a diagnosis of hepatocellular carcinoma, no significant associations with iron disorders and HFE gene mutations were found. Iron disorders were detected in patients with liver cirrhosis frequently but without significant association with HFE gene mutations. Only the homozygous C282Y mutation seems to occur more frequently in the selected population of patients with liver cirrhosis. As elevated biochemical iron indices accompanied liver iron deposits more frequently in liver cirrhosis compared to controls with chronic liver disease, there is a need for more extensive studies searching for

Analysis of single nucleotide variants of HFE gene and association to survival in The Cancer Genome Atlas GBM data.

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Lee, Sang Y; Zhu, Junjia; Salzberg, Anna C; Zhang, Bo; Liu, Dajiang J; Muscat, Joshua E; Langan, Sara T; Connor, James R

2017-01-01

Human hemochromatosis protein (HFE) is involved in iron metabolism. Two major HFE polymorphisms, H63D and C282Y, have been associated with an increased risk of cancers. Previously, we reported decreased gender effects in overall survival based on H63D or C282Y HFE polymorphisms patients with glioblastoma multiforme (GBM). However, the effect of other single nucleotide variation (SNV) in the HFE gene on the cancer development and progression has not been systematically studied. To expand our finding in a larger sample, and to identify other HFE SNV, we analyzed the frequency of somatic SNV in HFE gene and its relationship to survival in GBM patients using The Cancer Genome Atlas (TCGA) GBM (Caucasian only) database. We found 9 SNVs with increased frequency in blood normal of TCGA GBM patients compared to the 1000Genome. Among 9 SNVs, 7 SNVs were located in the intron and 2 SNVs (i.e., H63D, C282Y) in the exon of HFE gene. The statistical analysis demonstrated that blood normal samples of TCGA GBM have more H63D (p = 0.0002, 95% Confidence interval (CI): 0.2119-0.3223) or C282Y (p = 0.0129, 95% CI: 0.0474-0.1159) HFE polymorphisms than 1000Genome. The Kaplan-Meier survival curve for the 264 GBM samples revealed no difference between wild type (WT) HFE and H63D, and WT HFE and C282Y GBM patients. In addition, there was no difference in the survival of male/female GBM patients based on HFE genotype. There was no correlation between HFE expression and survival. In conclusion, the current results suggest that somatic HFE polymorphisms do not impact GBM patients' survival in the TCGA data set of GBM.

Analysis of single nucleotide variants of HFE gene and association to survival in The Cancer Genome Atlas GBM data.

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Sang Y Lee

Full Text Available Human hemochromatosis protein (HFE is involved in iron metabolism. Two major HFE polymorphisms, H63D and C282Y, have been associated with an increased risk of cancers. Previously, we reported decreased gender effects in overall survival based on H63D or C282Y HFE polymorphisms patients with glioblastoma multiforme (GBM. However, the effect of other single nucleotide variation (SNV in the HFE gene on the cancer development and progression has not been systematically studied. To expand our finding in a larger sample, and to identify other HFE SNV, we analyzed the frequency of somatic SNV in HFE gene and its relationship to survival in GBM patients using The Cancer Genome Atlas (TCGA GBM (Caucasian only database. We found 9 SNVs with increased frequency in blood normal of TCGA GBM patients compared to the 1000Genome. Among 9 SNVs, 7 SNVs were located in the intron and 2 SNVs (i.e., H63D, C282Y in the exon of HFE gene. The statistical analysis demonstrated that blood normal samples of TCGA GBM have more H63D (p = 0.0002, 95% Confidence interval (CI: 0.2119-0.3223 or C282Y (p = 0.0129, 95% CI: 0.0474-0.1159 HFE polymorphisms than 1000Genome. The Kaplan-Meier survival curve for the 264 GBM samples revealed no difference between wild type (WT HFE and H63D, and WT HFE and C282Y GBM patients. In addition, there was no difference in the survival of male/female GBM patients based on HFE genotype. There was no correlation between HFE expression and survival. In conclusion, the current results suggest that somatic HFE polymorphisms do not impact GBM patients' survival in the TCGA data set of GBM.

An extensive analysis of the hereditary hemochromatosis gene HFE and neighboring histone genes: associations with childhood leukemia.

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Davis, Charronne F; Dorak, M Tevfik

2010-04-01

The most common mutation of the HFE gene C282Y has shown a risk association with childhood acute lymphoblastic leukemia (ALL) in Welsh and Scottish case-control studies. This finding has not been replicated outside Britain. Here, we present a thorough analysis of the HFE gene in a panel of HLA homozygous reference cell lines and in the original population sample from South Wales (117 childhood ALL cases and 414 newborn controls). The 21 of 24 variants analyzed were from the HFE gene region extending 52 kb from the histone gene HIST1H1C to HIST1H1T. We identified the single-nucleotide polymorphism (SNP) rs807212 as a tagging SNP for the most common HFE region haplotype, which contains wild-type alleles of all HFE variants examined. This intergenic SNP rs807212 yielded a strong male-specific protective association (per allele OR = 0.38, 95% CI = 0.22-0.64, P (trend) = 0.0002; P = 0.48 in females), which accounted for the original C282Y risk association. In the HapMap project data, rs807212 was in strong linkage disequilibrium with 25 other SNPs spanning 151 kb around HFE. Minor alleles of these 26 SNPs characterized the most common haplotype for the HFE region, which lacked all disease-associated HFE variants. The HapMap data suggested positive selection in this region even in populations where the HFE C282Y mutation is absent. These results have implications for the sex-specific associations observed in this region and suggest the inclusion of rs807212 in future studies of the HFE gene and the extended HLA class I region.

Iron overload and HFE gene mutations in Czech patients with chronic liver diseases.

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Dostalikova-Cimburova, Marketa; Kratka, Karolina; Stransky, Jaroslav; Putova, Ivana; Cieslarova, Blanka; Horak, Jiri

2012-01-01

The aim of the study was to identify the prevalence of HFE gene mutations in Czech patients with chronic liver diseases and the influence of the mutations on iron status. The presence of HFE gene mutations (C282Y, H63D, and S65C) analyzed by the PCR-RFLP method, presence of cirrhosis, and serum iron indices were compared among 454 patients with different chronic liver diseases (51 with chronic hepatitis B, 122 with chronic hepatitis C, 218 with alcoholic liver disease, and 63 patients with hemochromatosis). Chronic liver diseases patients other than hemochromatics did not have an increased frequency of HFE gene mutations compared to controls. Although 33.3% of patients with hepatitis B, 43% of patients with hepatitis C, and 73.2% of patients with alcoholic liver disease had elevated transferrin saturation or serum ferritin levels, the presence of HFE gene mutations was not significantly associated with iron overload in these patients. Additionally, patients with cirrhosis did not have frequencies of HFE mutations different from those without cirrhosis. This study emphasizes the importance, not only of C282Y, but also of the H63D homozygous genetic constellation in Czech hemochromatosis patients. Our findings show that increased iron indices are common in chronic liver diseases but {\\it HFE} mutations do not play an important role in the pathogenesis of chronic hepatitis B, chronic hepatitis C, and alcoholic liver disease.

Study of the effect of HFE gene mutations on iron overload in ...

African Journals Online (AJOL)

Background: HFE gene mutations have been shown to be responsible for hereditary hemochromatosis. Their effect on iron load in β-thalassemia patients and carriers remains controversial. Objectives: We aimed to determine the prevalence of HFE gene mutations (C282Y and H63D) in β-thalassemia patients and carriers ...

The impact of H63D HFE gene carriage on hemoglobin and iron status in children.

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Barbara, Kaczorowska-Hac; Marcin, Luszczyk; Jedrzej, Antosiewicz; Wieslaw, Ziolkowski; Elzbieta, Adamkiewicz-Drozynska; Malgorzata, Mysliwiec; Ewa, Milosz; Jacek, Kaczor Jan

2016-12-01

The molecular mechanism that regulates iron homeostasis is based on a network of signals, which reflect on the iron requirements of the body. Hereditary hemochromatosis is a heterogenic metabolic syndrome which is due to unchecked transfer of iron into the bloodstream and its toxic effects on parenchymatous organs. It is caused by the mutation of genes that encode proteins that help hepcidin to monitor serum iron. These proteins include the human hemochromatosis protein -HFE, transferrin-receptor 2, hemojuvelin in rare instances, and ferroportin. HFE-related hemochromatosis is the most frequent form of the disease. Interestingly, the low penetrance of polymorphic HFE genes results in rare clinical presentation of the disease, predominantly in middle-aged males. Taking into account the wide dispersion of HFE mutation in our population and also its unknown role in heterozygotes, we analyzed the impact of H63D HFE carriage in the developmental age, with respect to gender, on the iron status and hemoglobin concentration of carriers in comparison to those of wild-type HFE gene (12.7 ± 3.07 years, 42 boys and 41 girls). H63D carriers presented higher blood iron, transferrin saturation, and ferritin concentration than wild-type probands (p HFE heterozygotes.

Reduced white matter MRI transverse relaxation rate in cognitively normal H63D-HFE human carriers and H67D-HFE mice.

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Meadowcroft, Mark D; Wang, Jianli; Purnell, Carson J; Peters, Douglas G; Eslinger, Paul J; Neely, Elizabeth B; Gill, David J; Vasavada, Megha; Ali-Rahmani, Fatima; Yang, Qing X; Connor, James R

2016-12-01

Mutations within the HFE protein gene sequence have been associated with increased risk of developing a number of neurodegenerative disorders. To this effect, an animal model has been created which incorporates the mouse homologue to the human H63D-HFE mutation: the H67D-HFE knock-in mouse. These mice exhibit alterations in iron management proteins, have increased neuronal oxidative stress, and a disruption in cholesterol regulation. However, it remains undetermined how these differences translate to human H63D carriers in regards to white matter (WM) integrity. To this endeavor, MRI transverse relaxation rate (R 2 ) parametrics were employed to test the hypothesis that WM alterations are present in H63D human carriers and are recapitulated in the H67D mice. H63D carriers exhibit widespread reductions in brain R 2 compared to non-carriers within white matter association fibers in the brain. Similar R 2 decreases within white matter tracts were observed in the H67D mouse brain. Additionally, an exacerbation of age-related R 2 decrease is found in the H67D animal model in white matter regions of interest. The decrease in R 2 within white matter tracts of both species is speculated to be multifaceted. The R 2 changes are hypothesized to be due to alterations in axonal biochemical tissue composition. The R 2 changes observed in both the human-H63D and mouse-H67D data suggest that modified white matter myelination is occurring in subjects with HFE mutations, potentially increasing vulnerability to neurodegenerative disorders.

Effects of strain and age on hepatic gene expression profiles in murine models of HFE-associated hereditary hemochromatosis.

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Lee, Seung-Min; Loguinov, Alexandre; Fleming, Robert E; Vulpe, Christopher D

2015-01-01

Hereditary hemochromatosis is an iron overload disorder most commonly caused by a defect in the HFE gene. While the genetic defect is highly prevalent, the majority of individuals do not develop clinically significant iron overload, suggesting the importance of genetic modifiers. Murine hfe knockout models have demonstrated that strain background has a strong effect on the severity of iron loading. We noted that hepatic iron loading in hfe-/- mice occurs primarily over the first postnatal weeks (loading phase) followed by a timeframe of relatively static iron concentrations (plateau phase). We thus evaluated the effects of background strain and of age on hepatic gene expression in Hfe knockout mice (hfe-/-). Hepatic gene expression profiles were examined using cDNA microarrays in 4- and 8-week-old hfe-/- and wild-type mice on two different genetic backgrounds, C57BL/6J (C57) and AKR/J (AKR). Genes differentially regulated in all hfe-/- mice groups, compared with wild-type mice, including those involved in cell survival, stress and damage responses and lipid metabolism. AKR strain-specific changes in lipid metabolism genes and C57 strain-specific changes in cell adhesion and extracellular matrix protein genes were detected in hfe-/- mice. Mouse strain and age are each significantly associated with hepatic gene expression profiles in hfe-/- mice. These affects may underlie or reflect differences in iron loading in these mice.

HFE gene mutations in coronary atherothrombotic disease

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Calado R.T.

2000-01-01

Full Text Available Although iron can catalyze the production of free radicals involved in LDL lipid peroxidation, the contribution of iron overload to atherosclerosis remains controversial. The description of two mutations in the HFE gene (Cys282Tyr and His63Asp related to hereditary hemochromatosis provides an opportunity to address the question of the association between iron overload and atherosclerosis. We investigated the prevalence of HFE mutations in 160 survivors of myocardial infarction with angiographically demonstrated severe coronary atherosclerotic disease, and in 160 age-, gender- and race-matched healthy control subjects. PCR amplification of genomic DNA followed by RsaI and BclI restriction enzyme digestion was used to determine the genotypes. The frequency of the mutant Cys282Tyr allele was identical among patients and controls (0.022; carrier frequency, 4.4%, whereas the mutant His63Asp allele had a frequency of 0.143 (carrier frequency, 27.5% in controls and of 0.134 (carrier frequency, 24.5% in patients. Compound heterozygotes were found in 2 of 160 (1.2% controls and in 1 of 160 (0.6% patients. The finding of a similar prevalence of Cys282Tyr and His63Asp mutations in the HFE gene among controls and patients with coronary atherothrombotic disease, indirectly questions the possibility of an association between hereditary hemochromatosis and atherosclerosis.

Hereditary Hemochromatosis (HFE genotypes in heart failure: Relation to etiology and prognosis

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Torp-Pedersen Christian

2010-07-01

Full Text Available Abstract Background It is believed that hereditary hemochromatosis (HH might play a role in cardiac disease (heart failure (HF and ischemia. Mutations within several genes are HH-associated, the most common being the HFE gene. In a large cohort of HF patients, we sought to determine the etiological role and the prognostic significance of HFE genotypes. Methods We studied 667 HF patients (72.7% men with depressed systolic function, enrolled in a multicentre trial with a follow-up period of up to 5 years. All were genotyped for the known HFE variants C282Y, H63D and S65C. Results The genotype and allele frequencies in the HF group were similar to the frequencies determined in the general Danish population. In multivariable analysis mortality was not predicted by C282Y-carrier status (HR 1.2, 95% CI: 0.8-1.7; H63D-carrier status (HR 1.0, 95% CI: 0.7-1.3; nor S65C-carrier status (HR 1.2, 95% CI: 0.7-2.0. We identified 27 (4.1% homozygous or compound heterozygous carriers of HFE variants. None of these carriers had a clinical presentation suggesting hemochromatosis, but hemoglobin and ferritin levels were higher than in the rest of the cohort. Furthermore, a trend towards reduced mortality was seen in this group in univariate analyses (HR 0.4, 95% CI: 0.2-0.9, p = 0.03, but not in multivariate (HR 0.5, 95% CI: 0.2-1.2. Conclusion HFE genotypes do not seem to be a significant contributor to the etiology of heart failure in Denmark. HFE variants do not affect mortality in HF.

Hereditary hemochromatosis (HFE) genotypes in heart failure: relation to etiology and prognosis

DEFF Research Database (Denmark)

Møller, Daniel Vega; Pecini, Redi; Gustafsson, Finn

2010-01-01

It is believed that hereditary hemochromatosis (HH) might play a role in cardiac disease (heart failure (HF) and ischemia). Mutations within several genes are HH-associated, the most common being the HFE gene. In a large cohort of HF patients, we sought to determine the etiological role...... and the prognostic significance of HFE genotypes....

Development of a HFE program for an operating NPP: Balancing between existing design practices and human factors standards

International Nuclear Information System (INIS)

Salo, Leena; Savioja, Paula

2014-01-01

This paper describes HFE program development project conducted at a Finnish power company Fortum. The aim of developing a formal HFE program was to improve integration of human factors issues in design of technical systems and to systematically document the HFE process of the company. As Fortum has a long tradition of designing control room solutions, the starting point of the HFE program development was the existing own design practices. On the other hand, the aim was to create a program which would comply with international guidelines such as NUREG-0711. The program development was conducted by tracing the HFE design practices in an on-going I and C modernization project. This empirical work was carried out by interviews of designers and other HFE key stake holders. After the explication of the current practices, the gaps, overlaps and differences in relation to the international standards and guidelines were identified. Based on an analysis of current practices and guidelines and standards a new HFE process model was created. The design process model can be followed in modifications which concern systems with human user interfaces of any kind. The model consists of five separate phases which comply with the general engineering design process model utilized at the company. The HFE program is intended to be both a practical guide on how to take human factors issues into consideration in the design of NPP systems and also a tool for the management of HFE activities

HFE H63D mutation frequency shows an increase in Turkish women with breast cancer

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Guler Emine

2006-02-01

Full Text Available Abstract Background The hereditary hemochromatosis gene HFE plays a pivotal role in iron homeostasis. The association between cancer and HFE hetero- or homozygosity has previously been shown including hepatocellular and nonhepatocellular malignancies. This study was performed to compare frequencies of HFE C282Y and H63D variants in Turkish women with breast cancer and healthy controls. Methods Archived DNA samples of Hacettepe University Oncology Institute were used in this study. The HFE gene was investigated by PCR-RFLP. Results All subjects studied were free from C282Y mutation. Thirty-nine patients had H63D mutation and were all heterozygous. H63D allele frequency was 22.2% (39/176 in the breast cancer patients, and 14% (28/200 in the healthy volunteers. Statistical analysis of cases with HFE H63D phenotype showed significant difference between breast cancer and healthy volunteers (P = 0.02. Conclusion Our results suggest that HFE H63D mutation frequencies were increased in the breast cancer patients in comparison to those in the general population. Also, odds ratios (odds ratio = 2.05 computed in this study suggest that H63D has a positive association with breast cancer.

Brain transcriptome perturbations in the Hfe(-/-) mouse model of genetic iron loading.

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Johnstone, Daniel; Graham, Ross M; Trinder, Debbie; Delima, Roheeth D; Riveros, Carlos; Olynyk, John K; Scott, Rodney J; Moscato, Pablo; Milward, Elizabeth A

2012-04-11

Severe disruption of brain iron homeostasis can cause fatal neurodegenerative disease, however debate surrounds the neurologic effects of milder, more common iron loading disorders such as hereditary hemochromatosis, which is usually caused by loss-of-function polymorphisms in the HFE gene. There is evidence from both human and animal studies that HFE gene variants may affect brain function and modify risks of brain disease. To investigate how disruption of HFE influences brain transcript levels, we used microarray and real-time reverse transcription polymerase chain reaction to assess the brain transcriptome in Hfe(-/-) mice relative to wildtype AKR controls (age 10 weeks, n≥4/group). The Hfe(-/-) mouse brain showed numerous significant changes in transcript levels (pgenes relating to transcriptional regulation (FBJ osteosarcoma oncogene Fos, early growth response genes), neurotransmission (glutamate NMDA receptor Grin1, GABA receptor Gabbr1) and synaptic plasticity and memory (calcium/calmodulin-dependent protein kinase IIα Camk2a). As previously reported for dietary iron-supplemented mice, there were altered levels of transcripts for genes linked to neuronal ceroid lipofuscinosis, a disease characterized by excessive lipofuscin deposition. Labile iron is known to enhance lipofuscin generation which may accelerate brain aging. The findings provide evidence that iron loading disorders can considerably perturb levels of transcripts for genes essential for normal brain function and may help explain some of the neurologic signs and symptoms reported in hemochromatosis patients. Copyright © 2012 Elsevier B.V. All rights reserved.

Rare HFE variants are the most frequent cause of hemochromatosis in non-c282y homozygous patients with hemochromatosis.

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Hamdi-Rozé, Houda; Beaumont-Epinette, Marie-Pascale; Ben Ali, Zeineb; Le Lan, Caroline; Loustaud-Ratti, Véronique; Causse, Xavier; Loreal, Olivier; Deugnier, Yves; Brissot, Pierre; Jouanolle, Anne-Marie; Bardou-Jacquet, Edouard

2016-12-01

p.Cys282Tyr (C282Y) homozygosity explains most cases of HFE-related hemochromatosis, but a significant number of patients presenting with typical type I hemochromatosis phenotype remain unexplained. We sought to describe the clinical relevance of rare HFE variants in non-C282Y homozygotes. Patients referred for hemochromatosis to the National Reference Centre for Rare Iron Overload Diseases from 2004 to 2010 were studied. Sequencing was performed for coding region and intronic flanking sequences of HFE, HAMP, HFE2, TFR2, and SLC40A1. Nine private HFE variants were identified in 13 of 206 unrelated patients. Among those, five have not been previously described: p.Leu270Argfs*4, p.Ala271Valfs*25, p.Tyr52*, p.Lys166Asn, and p.Asp141Tyr. Our results show that rare HFE variants are identified more frequently than variants in the other genes associated with iron overload. Rare HFE variants are therefore the most frequent cause of hemochromatosis in non-C282Y homozygote HFE patients. Am. J. Hematol. 91:1202-1205, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Mutant HFE H63D Protein Is Associated with Prolonged Endoplasmic Reticulum Stress and Increased Neuronal Vulnerability*

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Liu, Yiting; Lee, Sang Y.; Neely, Elizabeth; Nandar, Wint; Moyo, Mthabisi; Simmons, Zachary; Connor, James R.

2011-01-01

A specific polymorphism in the hemochromatosis (HFE) gene, H63D, is over-represented in neurodegenerative disorders such as amyotrophic lateral sclerosis and Alzheimer disease. Mutations of HFE are best known as being associated with cellular iron overload, but the mechanism by which HFE H63D might increase the risk of neuron degeneration is unclear. Here, using an inducible expression cell model developed from a human neuronal cell line SH-SY5Y, we reported that the presence of the HFE H63D protein activated the unfolded protein response (UPR). This response was followed by a persistent endoplasmic reticulum (ER) stress, as the signals of UPR sensors attenuated and followed by up-regulation of caspase-3 cleavage and activity. Our in vitro findings were recapitulated in a transgenic mouse model carrying Hfe H67D, the mouse equivalent of the human H63D mutation. In this model, UPR activation was detected in the lumbar spinal cord at 6 months then declined at 12 months in association with increased caspase-3 cleavage. Moreover, upon the prolonged ER stress, the number of cells expressing HFE H63D in early apoptosis was increased moderately. Cell proliferation was decreased without increased cell death. Additionally, despite increased iron level in cells carrying HFE H63D, it appeared that ER stress was not responsive to the change of cellular iron status. Overall, our studies indicate that the HFE H63D mutant protein is associated with prolonged ER stress and chronically increased neuronal vulnerability. PMID:21349849

Contribution of Hfe expression in macrophages to the regulation of hepatic hepcidin levels and iron loading

OpenAIRE

Makui, Hortence; Soares, Ricardo J.; Jiang, Wenlei; Constante, Marco; Santos, Manuela M.

2005-01-01

Hereditary hemochromatosis (HH), an iron overload disease associated with mutations in the HFE gene, is characterized by increased intestinal iron absorption and consequent deposition of excess iron, primarily in the liver. Patients with HH and Hfe-deficient (Hfe−/−) mice manifest inappropriate expression of the iron absorption regulator hepcidin, a peptide hormone produced by the liver in response to iron loading. In this study, we investigated the contribution of Hfe expression in macrophag...

The hemochromatosis protein HFE 20 years later: An emerging role in antigen presentation and in the immune system.

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Reuben, Alexandre; Chung, Jacqueline W; Lapointe, Réjean; Santos, Manuela M

2017-09-01

Since its discovery, the hemochromatosis protein HFE has been primarily defined by its role in iron metabolism and homeostasis, and its involvement in the genetic disease termed hereditary hemochromatosis (HH). While HH patients are typically afflicted by dysregulated iron levels, many are also affected by several immune defects and increased incidence of autoimmune diseases that have thereby implicated HFE in the immune response. Growing evidence has supported an immunological role for HFE with recent studies describing HFE specifically as it relates to MHC I antigen presentation. Here, we present a comprehensive overview of the relationship between iron metabolism, HFE, and the immune system to better understand the origin and cause of immune defects in HH patients. We further describe the role of HFE in MHC I antigen presentation and its potential to impair autoimmune responses in homeostatic conditions, a mechanism which may be exploited by tumors to evade immune surveillance. Overall, this increased understanding of the role of HFE in the immune response sets the stage for better treatment and management of HH and other iron-related diseases, as well as of the immune defects related to this condition. © 2017 The Authors. Immunity, Inflammation and Disease Published by John Wiley & Sons Ltd.

Global transcriptional response to Hfe deficiency and dietary iron overload in mouse liver and duodenum.

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Alejandra Rodriguez

2009-09-01

Full Text Available Iron is an essential trace element whose absorption is usually tightly regulated in the duodenum. HFE-related hereditary hemochromatosis (HH is characterized by abnormally low expression of the iron-regulatory hormone, hepcidin, which results in increased iron absorption. The liver is crucial for iron homeostasis as it is the main production site of hepcidin. The aim of this study was to explore and compare the genome-wide transcriptome response to Hfe deficiency and dietary iron overload in murine liver and duodenum. Illumina arrays containing over 47,000 probes were used to study global transcriptional changes. Quantitative RT-PCR (Q-RT-PCR was used to validate the microarray results. In the liver, the expression of 151 genes was altered in Hfe(-/- mice while dietary iron overload changed the expression of 218 genes. There were 173 and 108 differentially expressed genes in the duodenum of Hfe(-/- mice and mice with dietary iron overload, respectively. There was 93.5% concordance between the results obtained by microarray analysis and Q-RT-PCR. Overexpression of genes for acute phase reactants in the liver and a strong induction of digestive enzyme genes in the duodenum were characteristic of the Hfe-deficient genotype. In contrast, dietary iron overload caused a more pronounced change of gene expression responsive to oxidative stress. In conclusion, Hfe deficiency caused a previously unrecognized increase in gene expression of hepatic acute phase proteins and duodenal digestive enzymes.

Heat transfer and entropy generation analysis of HFE 7000 based nanorefrigerants

OpenAIRE

Helvaci, H.; Khan, Zulfiqar Ahmad

2017-01-01

In this study, two dimensional numerical simulations of forced convection flow of HFE 7000 based nanofluids in a horizontal circular tube subjected to a constant and uniform heat flux in laminar flow was performed by using single phase homogeneous model. Four different nanofluids considered in the present study are Al2O3, CuO, SiO2 and MgO nanoparticles dispersed in pure HFE 7000. The simulations were performed with particle volumetric concentrations of 0, 1, 4 and 6% and Reynolds number of 4...

HFE p.H63D polymorphism does not influence ALS phenotype and survival.

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Chiò, Adriano; Mora, Gabriele; Sabatelli, Mario; Caponnetto, Claudia; Lunetta, Christian; Traynor, Bryan J; Johnson, Janel O; Nalls, Mike A; Calvo, Andrea; Moglia, Cristina; Borghero, Giuseppe; Monsurrò, Maria Rosaria; La Bella, Vincenzo; Volanti, Paolo; Simone, Isabella; Salvi, Fabrizio; Logullo, Francesco O; Nilo, Riva; Giannini, Fabio; Mandrioli, Jessica; Tanel, Raffaella; Murru, Maria Rita; Mandich, Paola; Zollino, Marcella; Conforti, Francesca L; Penco, Silvana; Brunetti, Maura; Barberis, Marco; Restagno, Gabriella

2015-10-01

It has been recently reported that the p.His63Asp polymorphism of the HFE gene accelerates disease progression both in the SOD1 transgenic mouse and in amyotrophic lateral sclerosis (ALS) patients. We have evaluated the effect of HFE p.His63Asp polymorphism on the phenotype in 1351 Italian ALS patients (232 of Sardinian ancestry). Patients were genotyped for the HFE p.His63Asp polymorphism (CC, GC, and GG). All patients were also assessed for C9ORF72, TARDBP, SOD1, and FUS mutations. Of the 1351 ALS patients, 363 (29.2%) were heterozygous (GC) for the p.His63Asp polymorphism and 30 (2.2%) were homozygous for the minor allele (GG). Patients with CC, GC, and GG polymorphisms did not significantly differ by age at onset, site of onset of symptoms, and survival; however, in SOD1 patients with CG or GG polymorphism had a significantly longer survival than those with a CC polymorphism. Differently from what observed in the mouse model of ALS, the HFE p.His63Asp polymorphism has no effect on ALS phenotype in this large series of Italian ALS patients. Copyright © 2015 Elsevier Inc. All rights reserved.

C282Y polymorphism in the HFE gene is associated with risk of breast cancer.

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Liu, Xiaoyan; Lv, Chunlei; Luan, Xiaorong; Lv, Ming

2013-10-01

The C282Y and H63D polymorphisms in the HFE gene have been implicated in susceptibility of breast cancer, but a number of studies have reported inconclusive results. The aim of this study is to investigate the association between the C282Y and H63D polymorphisms in the HFE gene and breast cancer risk by meta-analysis. We searched PubMed and Embase databases, covering all related studies until March 2, 2013. Statistical analysis was performed using STATA 10.0. A total of 7 studies including 1,720 cases and 18,296 controls for HFE C282Y polymorphism and 5 studies including 942 cases and 1,571 controls for HFE H63D polymorphism were included in the meta-analysis. The results showed that HFE C282Y polymorphism was significantly associated with increased risk of breast cancer under homozygotes vs. wild-type model (OR = 2.06, 95%CI = 1.19-3.58) and recessive model (OR = 1.98, 95%CI = 1.14-3.44) but not under heterozygotes vs. wild-type model (OR = 0.97, 95%CI = 0.70-1.35), dominant model (OR = 1.00, 95%CI = 0.72-1.40) and multiplicative model (OR = 1.04, 95%CI = 0.76-1.42). However, we did not find any association between HFE H63D polymorphism and breast cancer risk under all genetic models. This current meta-analysis suggested that C282Y polymorphism rather than H63D might be associated with increased risk of breast cancer.

Natural selection on HFE in Asian populations contributes to enhanced non-heme iron absorption.

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Ye, Kaixiong; Cao, Chang; Lin, Xu; O'Brien, Kimberly O; Gu, Zhenglong

2015-06-10

HFE, a major regulator of iron (Fe) homeostasis, has been suggested to be under positive selection in both European and Asian populations. While the genetic variant under selection in Europeans (a non-synonymous mutation, C282Y) has been relatively well-studied, the adaptive variant in Asians and its functional consequences are still unknown. Identifying the adaptive HFE variants in Asians will not only elucidate the evolutionary history and the genetic basis of population difference in Fe status, but also assist the future practice of genome-informed dietary recommendation. Using data from the International HapMap Project, we confirmed the signatures of positive selection on HFE in Asian populations and identified a candidate adaptive haplotype that is common in Asians (52.35-54.71%) but rare in Europeans (5.98%) and Africans (4.35%). The T allele at tag SNP rs9366637 (C/T) captured 95.8% of this Asian-common haplotype. A significantly reduced HFE expression was observed in individuals carrying T/T at rs9366637 compared to C/C and C/T, indicating a possible role of gene regulation in adaptation. We recruited 57 women of Asian descent and measured Fe absorption using stable isotopes in those homozygous at rs9366637. We observed a 22% higher absorption in women homozygous for the Asian-common haplotype (T/T) compared to the control genotype (C/C). Additionally, compared with a group of age-matched Caucasian women, Asian women exhibited significantly elevated Fe absorption. Our results indicate parallel adaptation of HFE gene in Europeans and Asians with different genetic variants. Moreover, natural selection on HFE may have contributed to elevated Fe absorption in Asians. This study regarding population differences in Fe homeostasis has significant medical impact as high Fe level has been linked to an increased disease risk of metabolic syndromes.

Heterozygous Hfe gene deletion leads to impaired glucose homeostasis, but not liver injury in mice fed a high-calorie diet.

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Britton, Laurence; Jaskowski, Lesley; Bridle, Kim; Santrampurwala, Nishreen; Reiling, Janske; Musgrave, Nick; Subramaniam, V Nathan; Crawford, Darrell

2016-06-01

Heterozygous mutations of the Hfe gene have been proposed as cofactors in the development and progression of nonalcoholic fatty liver disease (NAFLD). Homozygous Hfe deletion previously has been shown to lead to dysregulated hepatic lipid metabolism and accentuated liver injury in a dietary mouse model of NAFLD We sought to establish whether heterozygous deletion of Hfe is sufficient to promote liver injury when mice are exposed to a high-calorie diet (HCD). Eight-week-old wild-type and Hfe(+/-) mice received 8 weeks of a control diet or HCD Liver histology and pathways of lipid and iron metabolism were analyzed. Liver histology demonstrated that mice fed a HCD had increased NAFLD activity score (NAS), steatosis, and hepatocyte ballooning. However, liver injury was unaffected by Hfe genotype. Hepatic iron concentration (HIC) was increased in Hfe(+/-) mice of both dietary groups. HCD resulted in a hepcidin-independent reduction in HIC Hfe(+/-) mice demonstrated raised fasting serum glucose concentrations and HOMA-IR score, despite unaltered serum adiponectin concentrations. Downstream regulators of hepatic de novo lipogenesis (pAKT, SREBP-1, Fas, Scd1) and fatty acid oxidation (AdipoR2, Pparα, Cpt1) were largely unaffected by genotype. In summary, heterozygous Hfe gene deletion is associated with impaired iron and glucose metabolism. However, unlike homozygous Hfe deletion, heterozygous gene deletion did not affect lipid metabolism pathways or liver injury in this model. © 2016 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of the American Physiological Society and The Physiological Society.

Spent nuclear fuel project, Cold Vacuum Drying Facility human factors engineering (HFE) analysis: Results and findings

International Nuclear Information System (INIS)

Garvin, L.J.

1998-01-01

This report presents the background, methodology, and findings of a human factors engineering (HFE) analysis performed in May, 1998, of the Spent Nuclear Fuels (SNF) Project Cold Vacuum Drying Facility (CVDF), to support its Preliminary Safety Analysis Report (PSAR), in responding to the requirements of Department of Energy (DOE) Order 5480.23 (DOE 1992a) and drafted to DOE-STD-3009-94 format. This HFE analysis focused on general environment, physical and computer workstations, and handling devices involved in or directly supporting the technical operations of the facility. This report makes no attempt to interpret or evaluate the safety significance of the HFE analysis findings. The HFE findings presented in this report, along with the results of the CVDF PSAR Chapter 3, Hazards and Accident Analyses, provide the technical basis for preparing the CVDF PSAR Chapter 13, Human Factors Engineering, including interpretation and disposition of findings. The findings presented in this report allow the PSAR Chapter 13 to fully respond to HFE requirements established in DOE Order 5480.23. DOE 5480.23, Nuclear Safety Analysis Reports, Section 8b(3)(n) and Attachment 1, Section-M, require that HFE be analyzed in the PSAR for the adequacy of the current design and planned construction for internal and external communications, operational aids, instrumentation and controls, environmental factors such as heat, light, and noise and that an assessment of human performance under abnormal and emergency conditions be performed (DOE 1992a)

A systematic review of human factors and ergonomics (HFE)-based healthcare system redesign for quality of care and patient safety.

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Xie, Anping; Carayon, Pascale

2015-01-01

Healthcare systems need to be redesigned to provide care that is safe, effective and efficient, and meets the multiple needs of patients. This systematic review examines how human factors and ergonomics (HFE) is applied to redesign healthcare work systems and processes and improve quality and safety of care. We identified 12 projects representing 23 studies and addressing different physical, cognitive and organisational HFE issues in a variety of healthcare systems and care settings. Some evidence exists for the effectiveness of HFE-based healthcare system redesign in improving process and outcome measures of quality and safety of care. We assessed risk of bias in 16 studies reporting the impact of HFE-based healthcare system redesign and found varying quality across studies. Future research should further assess the impact of HFE on quality and safety of care, and clearly define the mechanisms by which HFE-based system redesign can improve quality and safety of care.

The expression of the soluble HFE corresponding transcript is up-regulated by intracellular iron and inhibits iron absorption in a duodenal cell model

OpenAIRE

Silva, Bruno; Ferreira, Joana; Santos, Vera; Baldaia, Cilénia; Serejo, Fátima; Faustino, Paula

2014-01-01

Background and aims: Dietary iron absorption regulation is a key-step for the maintenance of body iron homeostasis. Besides the HFE full-length protein, the HFE gene codes for alternative splicing variants responsible for the synthesis of a soluble form of HFE protein (sHFE). Here we aimed to determine whether sHFE transcript levels respond to different iron conditions in duodenal, macrophage and hepatic cell models, as well, in vivo, in the liver. Furthermore, we determined the functional ef...

Regulation of HFE expression by poly(ADP-ribose) polymerase-1 (PARP1) through an inverted repeat DNA sequence in the distal promoter.

Science.gov (United States)

Pelham, Christopher; Jimenez, Tamara; Rodova, Marianna; Rudolph, Angela; Chipps, Elizabeth; Islam, M Rafiq

2013-12-01

Hereditary hemochromatosis (HH) is a common autosomal recessive disorder of iron overload among Caucasians of northern European descent. Over 85% of all cases with HH are due to mutations in the hemochromatosis protein (HFE) involved in iron metabolism. Although the importance in iron homeostasis is well recognized, the mechanism of sensing and regulating iron absorption by HFE, especially in the absence of iron response element in its gene, is not fully understood. In this report, we have identified an inverted repeat sequence (ATGGTcttACCTA) within 1700bp (-1675/+35) of the HFE promoter capable to form cruciform structure that binds PARP1 and strongly represses HFE promoter. Knockdown of PARP1 increases HFE mRNA and protein. Similarly, hemin or FeCl3 treatments resulted in increase in HFE expression by reducing nuclear PARP1 pool via its apoptosis induced cleavage, leading to upregulation of the iron regulatory hormone hepcidin mRNA. Thus, PARP1 binding to the inverted repeat sequence on the HFE promoter may serve as a novel iron sensing mechanism as increased iron level can trigger PARP1 cleavage and relief of HFE transcriptional repression. © 2013.

HFE gene variants modify the association between maternal lead burden and infant birthweight: a prospective birth cohort study in Mexico City, Mexico.

Science.gov (United States)

Cantonwine, David; Hu, Howard; Téllez-Rojo, Martha Maria; Sánchez, Brisa N; Lamadrid-Figueroa, Héctor; Ettinger, Adrienne S; Mercado-García, Adriana; Hernández-Avila, Mauricio; Wright, Robert O

2010-07-26

Neonatal growth is a complex process involving genetic and environmental factors. Polymorphisms in the hemochromatosis (HFE) iron regulatory genes have been shown to modify transport and toxicity of lead which is known to affect birth weight. We investigated the role of HFE C282Y, HFE H63 D, and transferrin (TF) P570 S gene variants in modifying the association of lead and infant birthweight in a cohort of Mexican mother-infant pairs. Subjects were initially recruited between 1994-1995 from three maternity hospitals in Mexico City and 411 infants/565 mothers had archived blood available for genotyping. Multiple linear regression models, stratified by either maternal/infant HFE or TF genotype and then combined with interaction terms, were constructed examining the association of lead and birthweight after controlling for covariates. 3.1%, 16.8% and 17.5% of infants (N=390) and 1.9%, 14.5% and 18.9% of mothers (N=533) carried the HFE C282Y, HFE H63D, and TF P570 S variants, respectively. The presence of infant HFE H63 D variants predicted 110.3 g (95% CI -216.1, -4.6) decreases in birthweight while maternal HFE H63 D variants predicted reductions of 52.0 g (95% CI -147.3 to 43.2). Interaction models suggest that both maternal and infant HFE H63 D genotype may modify tibia lead's effect on infant birthweight in opposing ways. In our interaction models, maternal HFE H63 D variant carriers had a negative association between tibia lead and birthweight. These results suggest that the HFE H63 D genotype modifies lead's effects on infant birthweight in a complex fashion that may reflect maternal-fetal interactions with respect to the metabolism and transport of metals.

Study of the HFE gene common polymorphisms in French patients with sporadic amyotrophic lateral sclerosis.

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Praline, Julien; Blasco, Hélène; Vourc'h, Patrick; Rat, Valérian; Gendrot, Chantal; Camu, William; Andres, Christian R

2012-06-15

Our objective was to investigate whether the C282Y (p.Cys 282 Tyr) and H63D (p. His 63 Asp) HFE polymorphisms were associated with sporadic amyotrophic lateral sclerosis (SALS) in the French population. We searched for a relation of HFE polymorphisms with the clinical characteristics of the disease. The HFE polymorphisms were studied in 824 patients with SALS and 583 controls. We compared the frequency of the polymorphisms between SALS and controls groups by univariate and multivariate statistics, taking into account gender, site, age-at-onset and survival. We did not observe significant difference in the frequency of H63D polymorphism between SALS and control group. We observed a significant difference for C282Y between patients and controls with a low frequency of the Y allele in patients (3.2%) compared to our control group (5.9%). Disease duration, distribution of gender, site-of-onset, age-at-onset did not differ between groups taking into account genotypes of each polymorphism. Our results in this large cohort of ALS patients indicate that H63D polymorphism is not associated with SALS in the French population. This conclusion does not exclude a weak effect of the HFE gene polymorphisms in certain ALS populations, or an effect of other rare HFE gene variants. Copyright © 2012 Elsevier B.V. All rights reserved.

La privación social y afectiva de la madre se asocia a alteraciones anatómicas y funcionales en el feto y recién nacido

Directory of Open Access Journals (Sweden)

Percy Pacora

2005-12-01

Full Text Available Objetivo: Demostrar que la privación social y afectiva en la madre se asocia a restricción del crecimiento fetal, muerte fetal, parto pretérmino, alteraciones anatómicas y funcionales en el feto y recién nacido. Materiales y Métodos: Estudio retrospectivo en el que se analizó la base de datos materno-perinatal del Hospital San Bartolomé. Se examinó tres grupos de gestantes con privación social y afectiva: 1 madres solteras (n=6561, 2 gestantes adolescentes con ausencia de control prenatal (n=2131 y 3 primigestas con talla menor de 160 cm (n=35722. Se comparó las complicaciones maternas y perinatales con las gestantes : 1 madres con unión estable (n=40629, 2 gestantes adolescentes con control prenatal (n=7644 y 3 primigestas con talla mayor de 159 cm (n=5264. Se empleó el odds ratio (OR y el intervalo de confianza al 95% (IC. Resultados: Las madres solteras presentaron mayor riesgo de falla en la función placentaria (OR 1,92, IC95% 1,51-2,44, restricción del crecimiento fetal (OR 2,02, IC95% 1,45-2,82, rotura prematura de membranas fetales (OR 1,28, IC95% 1,00-1,63 comparadas con las madres con unión de pareja estable. Las gestantes adolescentes con ausencia de control prenatal presentaron mayor riesgo de muerte fetal (OR 2,89, CI95% 1,85-4,50, rotura prematura de membranas fetales (OR 1,38, CI95% 1,18-1,62, parto pretérmino (OR 1,63, CI95% 1,39-1,91, neonato pequeño para la edad (OR 1,25, IC95% 1,08-1,44, morbilidad neonatal (OR 1,23, IC95% 1,07-1,41, asfixia perinatal (OR 2,73, IC95% 1,33-5,58, neonato con Ápgar bajo en minuto 1 (OR 1,26, IC95% 1,05-1,52, dificultad respiratoria (OR 1,51, IC95% 1,10-2,06, sepsis neonatal (OR 1,54, IC95% 1,19-1,99, prematuridad (OR 1,50, IC95% 1,27-1,78, muerte neonatal (OR 2,56, IC95% 1,88-3,48 y muerte perinatal (OR 3,02, IC95% 2,24-4,07 comparadas con las gestantes adolescentes con control prenatal. Las primigestas con talla menor de 160 cm presentaron mayor riesgo de ausencia de control

HFE C282Y/H63D Compound Heterozygotes Are at Low Risk of Hemochromatosis-Related Morbidity

OpenAIRE

Gurrin, Lyle C.; Bertalli, Nadine A.; Dalton, Gregory W.; Osborne, Nicholas J.; Constantine, Clare C.; McLaren, Christine E.; English, Dallas R.; Gertig, Dorota M.; Delatycki, Martin B.; Nicoll, Amanda J.; Southey, Melissa C.; Hopper, John L.; Giles, Graham G.; Anderson, Gregory J.; Olynyk, John K.

2009-01-01

The risk of hemochromatosis-related morbidity is unknown among HFE compound heterozygotes (C282Y/H63D). We used a prospective population-based cohort study to estimate the prevalence of elevated iron indices and hemochromatosis-related morbidity for compound heterozygotes. In all, 31,192 subjects of northern European descent were genotyped for HFE C282Y and H63D. An HFE-genotype stratified random sample of 1,438 subjects, followed for an average of 12 years to a mean age of 65 years, complete...

A role for sex and a common HFE gene variant in brain iron uptake.

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Duck, Kari A; Neely, Elizabeth B; Simpson, Ian A; Connor, James R

2018-03-01

HFE (high iron) is an essential protein for regulating iron transport into cells. Mutations of the HFE gene result in loss of this regulation causing accumulation of iron within the cell. The mutated protein has been found increasingly in numerous neurodegenerative disorders in which increased levels of iron in the brain are reported. Additionally, evidence that these mutations are associated with elevated brain iron challenges the paradigm that the brain is protected by the blood-brain barrier. While much has been studied regarding the role of HFE in cellular iron uptake, it has remained unclear what role the protein plays in the transport of iron into the brain. We investigated regulation of iron transport into the brain using a mouse model with a mutation in the HFE gene. We demonstrated that the rate of radiolabeled iron ( 59 Fe) uptake was similar between the two genotypes despite higher brain iron concentrations in the mutant. However, there were significant differences in iron uptake between males and females regardless of genotype. These data indicate that brain iron status is consistently maintained and tightly regulated at the level of the blood-brain barrier.

HFE p.C282Y gene variant is associated with varicose veins in Russian population.

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Sokolova, Ekaterina A; Shadrina, Alexandra S; Sevost'ianova, Kseniya S; Shevela, Andrey I; Soldatsky, Evgenii Yu; Seliverstov, Evgenii I; Demekhova, Marina Yu; Shonov, Oleg A; Ilyukhin, Evgenii A; Smetanina, Mariya A; Voronina, Elena N; Zolotukhin, Igor A; Filipenko, Maxim L

2016-08-01

Recently, the association of polymorphism rs1800562 (p.C282Y) in the hemochromatosis (HFE) gene with the increased risk of venous ulceration was shown. We hypothesized that HFE gene polymorphism might be involved not only in ulceration process, but also in susceptibility to primary varicose veins. We genotyped HFE p.C282Y (rs1800562) and p.H63D (rs1799945) variants in patients with primary varicose veins (n = 463) and in the control group (n = 754). In our study, p.282Y variant (rs1800562 A allele) was significantly associated with the risk of varicose veins (OR 1.79, 95 % CI = 1.11-2.89, P = 0.02). A borderline significant reverse association of p.63D variant (rs1799945 G allele) with venous leg ulcer development was revealed in Russians (OR 0.25, 95 % CI = 0.06-1.00, P = 0.05), but not in the meta-analysis (P = 0.56). We conclude that the HFE gene polymorphism can affect the risk of developing primary varicose veins.

Reduction of Skeletal Muscle Power in Adolescent Males Carrying H63D Mutation in the HFE Gene.

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Luszczyk, Marcin; Kaczorowska-Hac, Barbara; Milosz, Ewa; Adamkiewicz-Drozynska, Elzbieta; Ziemann, Ewa; Laskowski, Radoslaw; Flis, Damian; Rokicka-Hebel, Magdalena; Antosiewicz, Jedrzej

2017-01-01

Iron overload resulting from the mutation of genes involved in iron metabolism or excess dietary intake has been reported to negatively influence human physical performance. The aim of this study was to test the hypothesis that adolescents bearing a hemochromatosis gene (HFE) mutation in contrast to adults with the same mutation will not experience iron accumulation and their aerobic capacity will be similar to that of age-matched controls. Thirteen boys participated in the study. Seven of them are carriers of H63D mutation in the HFE gene and six were wild type. Fitness levels were assessed using the cardiopulmonary exercise test. In addition, iron status and inflammatory markers were determined. We observed that cardiovascular fitness was significantly lower in the group bearing the HFE mutation compared to the control group. Moreover, the HFE mutation group achieved lower maximal power output compared to the control group. There were no differences in blood ferritin concentrations between the two groups which indicates similar amounts of stored iron. Obtained data do not confirm our hypothesis. On the contrary, it was demonstrated that HFE mutation is associated with a lower level of aerobic capacity, even in the absence of iron accumulation.

Association of HFE common mutations with Parkinson's disease, Alzheimer's disease and mild cognitive impairment in a Portuguese cohort

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Morgadinho Ana S

2006-07-01

Full Text Available Abstract Background Pathological brain iron deposition has been implicated as a source of neurotoxic reactive oxygen species in Alzheimer (AD and Parkinson diseases (PD. Iron metabolism is associated with the gene hemochromatosis (HFE Human genome nomenclature committee ID:4886, and mutations in HFE are a cause of the iron mismetabolism disease, hemochromatosis. Several reports have tested the association of HFE variants with neurodegenerative diseases, such as AD and PD with conflicting results. Methods Genotypes were analysed for the two most common variants of HFE in a series of 130 AD, 55 Mild Cognitive Impairment (MCI and 132 PD patients. Additionally, a series of 115 healthy age-matched controls was also screened. Results A statistically significant association was found in the PD group when compared to controls, showing that the presence of the C282Y variant allele may confer higher risk for developing the disease. Conclusion Taken together these results suggest that the common variants in HFE may be a risk factor for PD, but not for AD in the Portuguese population.

HFE Cys282Tyr homozygotes with serum ferritin concentrations below 1000 microg/L are at low risk of hemochromatosis.

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Allen, Katrina J; Bertalli, Nadine A; Osborne, Nicholas J; Constantine, Clare C; Delatycki, Martin B; Nisselle, Amy E; Nicoll, Amanda J; Gertig, Dorota M; McLaren, Christine E; Giles, Graham G; Hopper, John L; Anderson, Gregory J; Olynyk, John K; Powell, Lawrie W; Gurrin, Lyle C

2010-09-01

Hemochromatosis gene (HFE)-associated hereditary hemochromatosis (HH) is a genetic predisposition to iron overload and subsequent signs and symptoms of disease that potentially affects approximately 80,000 persons in Australia and almost 1 million persons in the United States. Most clinical cases are homozygous for the Cys282Tyr (C282Y) mutation in the HFE gene, with serum ferritin (SF) concentration >1000 microg/L as the strongest predictor of cirrhosis. The optimal treatment regimen for those with SF concentrations above the normal range but aged 40-69 years. An HFE-stratified random sample of 1438 participants including all C282Y homozygotes with iron studies 12 years apart were examined by physicians blinded to participants' HFE genotype. All previously undiagnosed C282Y homozygotes (35 male, 67 female) and all HFE wild-types (131 male, 160 female) with baseline and follow-up SF concentrations age when disease would be expected to have developed. These observations have implications for the management of C282Y homozygotes.

A mutation in the HFE gene is associated with altered brain iron profiles and increased oxidative stress in mice.

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Nandar, Wint; Neely, Elizabeth B; Unger, Erica; Connor, James R

2013-06-01

Because of the increasing evidence that H63D HFE polymorphism appears in higher frequency in neurodegenerative diseases, we evaluated the neurological consequences of H63D HFE in vivo using mice that carry H67D HFE (homologous to human H63D). Although total brain iron concentration did not change significantly in the H67D mice, brain iron management proteins expressions were altered significantly. The 6-month-old H67D mice had increased HFE and H-ferritin expression. At 12 months, H67D mice had increased H- and L-ferritin but decreased transferrin expression suggesting increased iron storage and decreased iron mobilization. Increased L-ferritin positive microglia in H67D mice suggests that microglia increase iron storage to maintain brain iron homeostasis. The 6-month-old H67D mice had increased levels of GFAP, increased oxidatively modified protein levels, and increased cystine/glutamate antiporter (xCT) and hemeoxygenase-1 (HO-1) expression indicating increased metabolic and oxidative stress. By 12 months, there was no longer increased astrogliosis or oxidative stress. The decrease in oxidative stress at 12 months could be related to an adaptive response by nuclear factor E2-related factor 2 (Nrf2) that regulates antioxidant enzymes expression and is increased in the H67D mice. These findings demonstrate that the H63D HFE impacts brain iron homeostasis, and promotes an environment of oxidative stress and induction of adaptive mechanisms. These data, along with literature reports on humans with HFE mutations provide the evidence to overturn the traditional paradigm that the brain is protected from HFE mutations. The H67D knock-in mouse can be used as a model to evaluate how the H63D HFE mutation contributes to neurodegenerative diseases. Copyright © 2013 Elsevier B.V. All rights reserved.

Precipitating factors of porphyria cutanea tarda in Brazil with emphasis on hemochromatosis gene (HFE) mutations. Study of 60 patients.

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Vieira, Fatima Mendonça Jorge; Nakhle, Maria Cristina; Abrantes-Lemos, Clarice Pires; Cançado, Eduardo Luiz Rachid; Reis, Vitor Manoel Silva dos

2013-01-01

Porphyria cutanea tarda is the most common form of porphyria, characterized by the decreased activity of the uroporphyrinogen decarboxylase enzyme. Several reports associated HFE gene mutations of hereditary hemochromatosis with porphyria cutanea tarda worldwide, although up to date only one study has been conducted in Brazil. Investigation of porphyria cutanea tarda association with C282Y and H63D mutations in the HFE gene. Identification of precipitating factors (hepatitis C, HIV, alcoholism and estrogen) and their link with HFE mutations. An ambispective study of 60 patients with PCT was conducted during the period from 2003 to 2012. Serological tests for hepatitis C and HIV were performed and histories of alcohol abuse and estrogen intake were investigated. HFE mutations were identified with real-time PCR. Porphyria cutanea tarda predominated in males and alcohol abuse was the main precipitating factor. Estrogen intake was the sole precipitating factor present in 25% of female patients. Hepatitis C was present in 41.7%. All HIV-positive patients (15.3%) had a history of alcohol abuse. Allele frequency for HFE mutations, i.e., C282Y (p = 0.0001) and H63D (p = 0.0004), were significantly higher in porphyria cutanea tarda patients, compared to control group. HFE mutations had no association with the other precipitating factors. Alcohol abuse, hepatitis C and estrogen intake are prevalent precipitating factors in our porphyria cutanea tarda population; however, hemochromatosis in itself can also contribute to the outbreak of porphyria cutanea tarda, which makes the research for HFE mutations necessary in these patients.

Association of HFE gene mutations with nonalcoholic fatty liver disease in the Iranian population.

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Saremi, L; Lotfipanah, S; Mohammadi, M; Hosseinzadeh, H; Sayad, A; Saltanatpour, Z

2016-10-31

To determine whether the HFE gene variants H63D and C282Y are associated with NAFLD in persons with type 2 diabetes, we conducted a case-control study including 145 case of NAFLD patients with a history of type 2 diabetes and 145 matching control. The genomic DNA was extracted from the peripheral venous blood and the genotyping of HFE gene mutations was analyzed using the PCR-RFLP technique. Statistical analysis was performed using SPSS 12.0 software by χ2 test, t test and ANOVA (P<0.05). Data showed no increased frequency of HFE mutations in persons with type 2 diabetes and no association between H63D mutation and NAFLD in the study population. Also, we analyzed index of physiological variables including FBS, lipid profile (TC, TG, LDL-C, and HDL-C), BMI, HbA1c, and micro albuminuria and Cr levels). Data showed there are no relationship between these indexes and HFE gene mutations and either NAFLD as a complication of diabetes. But our results showed a relationship between C282Y mutation and NAFLD in persons with type 2 diabetes. C282Y mutation might be a genetic marker of NAFLD in Iranian population.

A family with hereditary hemochromatosis carrying HFE gene splice site mutation: a case report

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NING Huibin

2017-01-01

Full Text Available ObjectiveTo investigate a new type of HFE gene mutation in a family with hereditary hemochromatosis (HH. MethodsThe analysis of HFE gene was performed for one patient with a confirmed diagnosis of HH and five relatives. Blood genomic DNA was extracted and PCR multiplication was performed for the exon and intron splice sequences of related HFE, HJV, HAMP, transferrin receptor 2 (TfR2, and SLC40A1 genes. After agarose gel electrophoresis and purification, bi-directional direct sequencing was performed to detect mutation sites. ResultsThe proband had abnormal liver function and increases in serum iron, total iron binding capacity, serum ferritin, and transferrin saturation, as well as T→C homozygous mutation in the fourth base of intron 2 in the intervening sequence of the exon EXON2 of HFE gene (IVs 2+4T→C, C/C homozygous, splicing, abnormal. There were no abnormalities in HJV, HAMP, TfR2, and SLC40A1 genes. The proband′s son had the same homozygous mutation, three relatives had heterozygous mutations, and one relative had no abnormal mutations. ConclusionGene detection plays an important role in the diagnosis of hemochromatosis, and IVs 2+4T→C mutation may be a new pathogenic mutation for HH in China.

A Mouse Model of Cardiomyopathy Induced by Mutations in the Hemochromatosis HFE Gene.

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Djemai, Haidar; Thomasson, Rémi; Trzaskus, Yvan; Mougenot, Nathalie; Meziani, Amira; Toussaint, Jean-François; Noirez, Philippe; Vitiello, Damien

2017-07-01

The heart is 1 of the organs most affected by hereditary hemochromatosis (HH). The clinical impact of cardiomyopathy in patients with HH requires a particular diagnosis and less invasive treatments. We developed a model of cardiomyopathy in knockout (KO) mice for the high-Fe (HFE) gene and assessed left ventricular (LV) function and structure from 7-20 months. Male wild-type (WT) heterozygous and KO SV129 mice for the HFE gene were used in this study. Twenty-four mice were used to assess LV function and structure by echocardiography at 7, 14, 18, and 20 months. Evaluations of LV function and structure and myocardial fibrosis were performed at 7 and 20 months. The percent decrease of LV thickness-to-radius ratio between 7 and 20 months was higher in KO mice compared with WT mice (-30.2% ± 5.3% vs -10.5% ± 4.9%; P HFE-related hemochromatosis. Copyright © 2017 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.

Reduction of Skeletal Muscle Power in Adolescent Males Carrying H63D Mutation in the HFE Gene

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Marcin Luszczyk

2017-01-01

Full Text Available Iron overload resulting from the mutation of genes involved in iron metabolism or excess dietary intake has been reported to negatively influence human physical performance. The aim of this study was to test the hypothesis that adolescents bearing a hemochromatosis gene (HFE mutation in contrast to adults with the same mutation will not experience iron accumulation and their aerobic capacity will be similar to that of age-matched controls. Thirteen boys participated in the study. Seven of them are carriers of H63D mutation in the HFE gene and six were wild type. Fitness levels were assessed using the cardiopulmonary exercise test. In addition, iron status and inflammatory markers were determined. We observed that cardiovascular fitness was significantly lower in the group bearing the HFE mutation compared to the control group. Moreover, the HFE mutation group achieved lower maximal power output compared to the control group. There were no differences in blood ferritin concentrations between the two groups which indicates similar amounts of stored iron. Obtained data do not confirm our hypothesis. On the contrary, it was demonstrated that HFE mutation is associated with a lower level of aerobic capacity, even in the absence of iron accumulation.

Haemochromatosis HFE gene polymorphisms as potential modifiers of hereditary nonpolyposis colorectal cancer risk and onset age.

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Shi, Zumin; Johnstone, Daniel; Talseth-Palmer, Bente A; Evans, Tiffany-Jane; Spigelman, Allan D; Groombridge, Claire; Milward, Elizabeth A; Olynyk, John K; Suchy, Janina; Kurzawski, Grzegorz; Lubinski, Jan; Scott, Rodney J

2009-07-01

Hereditary nonpolyposis colorectal cancer (HNPCC) is characterized by germline mutations in DNA mismatch repair genes; however, variation in disease expression suggests that there are potential modifying factors. Polymorphisms of the HFE gene, which cause the iron overload disorder hereditary haemochromatosis, have been proposed as potential risk factors for the development of colorectal cancer (CRC). To understand the relationship between HNPCC disease phenotype and polymorphisms of the HFE gene, a total of 362 individuals from Australia and Poland with confirmed causative MMR gene mutations were genotyped for the HFE C282Y and H63D polymorphisms. A significantly increased risk of developing CRC was observed for H63D homozygotes when compared with combined wild-type homozygotes and heterozygotes (hazard ratio = 2.93, p = 0.007). Evidence for earlier CRC onset was also observed in H63D homozygotes with a median age of onset 6 years earlier than wild type or heterozygous participants (44 vs. 50 years of age). This effect was significant by all tests used (log-rank test p = 0.026, Wilcoxon p = 0.044, Tarone-Ware p = 0.035). No association was identified for heterozygosity of either polymorphism and limitations on power-prevented investigation of C282Y homozygosity or compound C282Y/H63D heterozygosity. In the Australian sample only, women had a significantly reduced risk of developing CRC when compared with men (hazard ratio = 0.58, p = 0.012) independent of HFE genotype for either single nucleotide polymorphisms. In conclusion, homozygosity for the HFE H63D polymorphism seems to be a genetic modifier of disease expression in HNPCC. Understanding the mechanisms by which HFE interrelates with colorectal malignancies could lead to reduction of disease risk in HNPCC.

Hepcidin regulation in wild-type and Hfe knockout mice in response to alcohol consumption: evidence for an alcohol-induced hypoxic response.

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Heritage, Mandy L; Murphy, Therese L; Bridle, Kim R; Anderson, Gregory J; Crawford, Darrell H G; Fletcher, Linda M

2009-08-01

Expression of Hamp1, the gene encoding the iron regulatory peptide hepcidin, is inappropriately low in HFE-associated hereditary hemochromatosis and Hfe knockout mice (Hfe(-/-)). Since chronic alcohol consumption is also associated with disturbances in iron metabolism, we investigated the effects of alcohol consumption on hepcidin mRNA expression in Hfe(-/-) mice. Hfe(-/-) and C57BL/6 (wild-type) mice were pair-fed either an alcohol liquid diet or control diet for up to 8 weeks. The mRNA levels of hepcidin and ferroportin were measured at the mRNA level by RT-PCR and protein expression of hypoxia inducible factor-1 alpha (HIF-1alpha) was measured by western blot. Hamp1 mRNA expression was significantly decreased and duodenal ferroportin expression was increased in alcohol-fed wild-type mice at 8 weeks. Time course experiments showed that the decrease in hepcidin mRNA was not immediate, but was significant by 4 weeks. Consistent with the genetic defect, Hamp1 mRNA was decreased and duodenal ferroportin mRNA expression was increased in Hfe(-/-) mice fed on the control diet compared with wild-type animals and alcohol further exacerbated these effects. HIF-1alpha protein levels were elevated in alcohol-fed wild-type animals compared with controls. Alcohol may decrease Hamp1 gene expression independently of the HFE pathway possibly via alcohol-induced hypoxia.

Intragenic haplotype analysis of common HFE mutations in the ...

Indian Academy of Sciences (India)

mutation <100 generations ago in the Celtic populations of mainland Europe, with a ... 0.9–5.8%, evidencing regional differences in distribution across the ..... and H63D alleles in the HFE gene among various Jewish ethnic groups in Israel: a ...

Computational Profiling of Deleterious Non-Synonymous SNP’s in HFE

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S. Sarath Raj

2017-12-01

Full Text Available Liver cirrhosis describes a condition where scar tissue gradually replaces healthy cells in liver. The main causes are sustained, excessive alcohol consumption, viral hepatitis B and C, and fatty liver disease - however, there are other possible causes. Hemochromatosis is most common form of iron overload disease. Three types of hemochromatosis are primary hemochromatosis, also called hereditary hemochromatosis; secondary hemochromatosis; and neonatal hemochromatosis. The HFE gene helps regulate the amount of iron absorbed from food and inherited genetic defects or mutation in HFE [C282Y] cause primary hemochromatosis. Computational approach is sought to determine other similar mutations in this gene. In-silico tools such as SIFT, Polyphen 2.0, and PROVEAN were employed to determine the various deleterious ns-SNPs of HFE that may influence cystic fibrosis.

HFE gene C282Y variant is associated with colorectal cancer in Caucasians: a meta-analysis.

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Chen, Weidong; Zhao, Hua; Li, Tiegang; Yao, Hongliang

2013-08-01

The HFE gene has been suggested to play an important role in the pathogenesis of colorectal cancer. However, the results have been conflicting. In this study, we performed a meta-analysis to clarify the association of HFE gene C282Y variant with colorectal cancer. PubMed and Embase were retrieved to identify the potential literature. Pooled odds ratio (OR) with 95 % confidence interval (CI) was calculated using fixed- or random-effects model. A total of eight papers including nine studies (7,588 colorectal cancer cases and 81,571 controls) for HFE gene C282Y variant were included in the meta-analysis. The result indicated that HFE gene C282Y variant was significantly associated with colorectal cancer under recessive model (OR = 2.00, 95 % CI = 1.32-3.04), with no evidence of between-study heterogeneity (I (2) = 0.2 %, p = 0.432). Further subgroup analysis by number of cases suggested the effect was significant in studies with more than 500 cases (OR = 2.51, 95 % CI = 1.58-3.98, I (2) = 0.0 %, p = 0.921), but not in studies with less than 500 cases (OR = 0.75, 95 % CI = 0.28-1.97, I (2) = 0.0 %, p = 0.622). The current meta-analysis supported the positive association of HFE gene C282Y variant with colorectal cancer. Further large-scale studies with the consideration for gene-gene/gene-environment interactions should be conducted to investigate the association.

Iron regulation of hepcidin despite attenuated Smad1,5,8 signaling in mice without transferrin receptor 2 or Hfe

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Corradini, Elena; Rozier, Molly; Meynard, Delphine; Odhiambo, Adam; Lin, Herbert Y.; Feng, Qi; Migas, Mary C.; Britton, Robert S.; Babitt, Jodie L.; Fleming, Robert E.

2011-01-01

Background & Aims HFE and transferrin receptor 2 (TFR2) are each necessary for the normal relationship between body iron status and liver hepcidin expression. In murine Hfe and Tfr2 knockout models of hereditary hemochromatosis (HH), signal transduction to hepcidin via the bone morphogenetic protein 6 (Bmp6)/Smad1,5,8 pathway is attenuated. We examined the effect of dietary iron on regulation of hepcidin expression via the Bmp6/Smad1,5,8 pathway using mice with targeted disruption of Tfr2, Hfe, or both genes. Methods Hepatic iron concentrations and mRNA expression of Bmp6 and hepcidin were compared with wild-type mice in each of the HH models on standard or iron-loading diets. Liver phospho-Smad (P-Smad)1,5,8 and Id1 mRNA levels were measured as markers of Bmp/Smad signaling. Results While Bmp6 expression was increased, liver hepcidin and Id1 expression were decreased in each of the HH models compared with wild-type mice. Each of the HH models also demonstrated attenuated P-Smad1,5,8 levels relative to liver iron status. Mice with combined Hfe/Tfr2 disruption were most affected. Dietary iron loading increased hepcidin and Id1 expression in each of the HH models. Compared with wild-type mice, HH mice demonstrated attenuated (Hfe knockout) or no increases in P-Smad1,5,8 levels in response to dietary iron loading. Conclusions These observations demonstrate that Tfr2 and Hfe are each required for normal signaling of iron status to hepcidin via Bmp6/Smad1,5,8 pathway. Mice with combined loss of Hfe and Tfr2 up-regulate hepcidin in response to dietary iron loading without increases in liver BMP6 mRNA or steady-state P-Smad1,5,8 levels. PMID:21745449

Serum hepcidin levels, iron status, and HFE gene alterations during the first year of life in healthy Spanish infants.

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Aranda, Nuria; Bedmar, Cristina; Arija, Victoria; Jardí, Cristina; Jimenez-Feijoo, Rosa; Ferré, Natalia; Tous, Monica

2018-06-01

The aims of this study were to describe hepcidin levels and to assess their associations with iron status and the main variants in the HFE gene in healthy and full-term newborns during the first year of life, as a longitudinal study conducted on 140 infants. Anthropometric and biochemical parameters, hepcidin, hemoglobin (Hb), serum ferritin (SF), transferrin saturation (TS), mean corpuscular volume (MCV), and C-reactive protein (CRP), were assessed in 6- and 12-month-olds. Infants were genotyped for the three main HFE variants: C282Y, H63D, and S65C. Hepcidin levels increased from 6 to 12 months of age (43.7 ± 1.5 to 52.0 ± 1.5 ng/mL; p HFE gene (p = 0.046 and p = 0.048 in 6- and 12-month-olds, respectively). However, this association was not found in HFE-alteration-carrying infants. Hepcidin levels increased in healthy infants during the first year of life and were positively associated with iron levels only in infants with wild-type HFE gene, a situation that requires further investigation.

[The polymorphism of catechol-O-methyltransferase (COMT) and hemochromatosis (HFE) genes in the radiocontaminated regions residents with different chromosome aberration frequency].

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Ivanova, T I; Kondrashova, T V; Krikunova, L I; Smirnova, I A; Shentereva, N I; Sychenkova, N I; Rykova, E V; Zharikova, I A; Khorokhorina, V A; Riabchenko, N I; Zamulaeva, I A

2010-01-01

The association between polymorphisms in genes COMT, HFE that takes part in oxidative stress regulation, and chromosome aberration frequency in lymphocytes was assessed in 278 female residents of radiation polluted regions of Central Russia: Bryansk (322 kBk/m2) and Tula Districts (137Cs - 171 kBk/m2). The C187G, G845A genotyping of HFE and G1947A (H/L) of COMT was done by means of polymerase chain reaction-restriction fragment length polymorphism. Studied population was divided into 3 subgroups by level of chromosome aberrations per cell (0-2, 3-4, >5). There was shown statistically significant difference in distribution of COMTand HFE genotypes between the groups. The high frequency of chromosome aberrations (> or = 5%) was associated with homozygotes of the high activity COMT G/G and HFE CC. Heterozygotes for G1947A COMT and C187G HFE reveal negative association with the high frequency of chromosome aberrations and correspond to "resistance factors".

Genetic disruption of NRF2 promotes the development of necroinflammation and liver fibrosis in a mouse model of HFE-hereditary hemochromatosis.

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Duarte, Tiago L; Caldas, Carolina; Santos, Ana G; Silva-Gomes, Sandro; Santos-Gonçalves, Andreia; Martins, Maria João; Porto, Graça; Lopes, José Manuel

2017-04-01

In hereditary hemochromatosis, iron deposition in the liver parenchyma may lead to fibrosis, cirrhosis and hepatocellular carcinoma. Most cases are ascribed to a common mutation in the HFE gene, but the extent of clinical expression is greatly influenced by the combined action of yet unidentified genetic and/or environmental modifying factors. In mice, transcription factor NRF2 is a critical determinant of hepatocyte viability during exposure to acute dietary iron overload. We evaluated if the genetic disruption of Nrf2 would prompt the development of liver damage in Hfe -/- mice (an established model of human HFE-hemochromatosis). Wild-type, Nrf2 -/- , Hfe -/- and double knockout (Hfe/Nrf2 -/- ) female mice on C57BL/6 genetic background were sacrificed at the age of 6 (young), 12-18 (middle-aged) or 24 months (old) for evaluation of liver pathology. Despite the parenchymal iron accumulation, Hfe -/- mice presented no liver injury. The combination of iron overload (Hfe -/- ) and defective antioxidant defences (Nrf2 -/- ) increased the number of iron-related necroinflammatory lesions (sideronecrosis), possibly due to the accumulation of toxic oxidation products such as 4-hydroxy-2-nonenal-protein adducts. The engulfment of dead hepatocytes led to a gradual accumulation of iron within macrophages, featuring large aggregates. Myofibroblasts recruited towards the injury areas produced substantial amounts of collagen fibers involving the liver parenchyma of double-knockout animals with increased hepatic fibrosis in an age-dependent manner. The genetic disruption of Nrf2 promotes the transition from iron accumulation (siderosis) to liver injury in Hfe -/- mice, representing the first demonstration of spontaneous hepatic fibrosis in the long term in a mouse model of hereditary hemochromatosis displaying mildly elevated liver iron. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

Prevalence of C282Y, H63D, and S65C mutations in hereditary HFE-hemochromatosis gene in Lithuanian population.

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Kucinskas, Laimutis; Juzenas, Simonas; Sventoraityte, Jurgita; Cedaviciute, Ruta; Vitkauskiene, Astra; Kalibatas, Vytenis; Kondrackiene, Jurate; Kupcinskas, Limas

2012-04-01

HFE-hemochromatosis is a common autosomal recessive disease caused by HFE gene mutations and characterized as iron overload and failure of different organs. The aim of this study was to determine the prevalence of C282Y (c.845 G>A), H63D (c.187 C>G), and S65C (c.193A>T) alleles of HFE gene in the Lithuanian population. One thousand and eleven healthy blood donors of Lithuanian nationality were examined in four different ethnic Lithuanian regions to determine HFE gene alleles and genotype frequencies. The samples of DNA were analyzed for the presence of restriction fragment length polymorphism and validated by DNA sequencing. Among 1,011 blood donors tested, the frequency of C282Y, H63D, and S65C alleles were 2.6%, 15.9%, and 1.9%, respectively. One third of the tested subjects (n = 336) had at least one of the C282Y or H63D HFE gene mutations. The screening of Lithuanian blood donors has detected 13 (1.3%) subjects with a genotype C282Y/C282Y or C282Y/H63D responsible for the development of HFE-hemochromatosis. The prevalence of C282Y mutation was significantly higher among the inhabitants of Zemaitija (Somogitia) at the Baltic Sea area (5.9%) in comparison to the regions of continental part of Lithuania (2.4% in Dzukija, 2.3% in Aukstaitija, and 2% in Suvalkija, p HFE gene mutations in ethnic Lithuanians showed that the frequencies of H63D, C282Y, and S65C of HFE gene alleles are similar to the other North-Eastern Europeans, especially in the Baltic region (Estonia, Latvia), Poland, and part of Russia (Moscow region).

An Excel Macro to Plot the HFE-Diagram to Identify Sea Water Intrusion Phases.

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Giménez-Forcada, Elena; Sánchez San Román, F Javier

2015-01-01

A hydrochemical facies evolution diagram (HFE-D) is a multirectangular diagram, which is a useful tool in the interpretation of sea water intrusion processes. This method note describes a simple method for generating an HFE-D plot using the spreadsheet software package, Microsoft Excel. The code was applied to groundwater from the alluvial coastal plain of Grosseto (Tuscany, Italy), which is characterized by a complex salinization process in which sea water mixes with sulfate or bicarbonate recharge water. © 2014, National GroundWater Association.

Analysis of HFE gene mutations and HLA-A alleles in Brazilian patients with iron overload

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Rodolfo Delfini Cançado

Full Text Available CONTEXT AND OBJECTIVE: Hemochromatosis is a common inherited disorder of iron metabolism and one of the most important causes of iron overload. The objective was to analyze the presence of C282Y, H63D and S65C mutations in the HFE gene and HLA-A alleles for a group of Brazilian patients with iron overload, and to correlate genotype with clinical and laboratory variables. DESIGN AND SETTING: Prospective study, in Discipline of Hematology and Oncology, Faculdade de Ciências Médicas da Santa Casa de Misericórdia de São Paulo. METHODS: We studied 35 patients with iron overload seen at our outpatient unit between January 2001 and December 2003. Fasting levels of serum iron and ferritin, and total iron-binding capacity, were assayed using standard techniques. Determinations of C282Y, H63D and S65C mutations in the HFE gene and of HLA-A alleles were performed by polymerase chain reaction (PCR. RESULTS: Twenty-six out of 35 patients (74% presented at least one of the HFE gene mutations analyzed. Among these, five (14% were C282Y/C282Y, four (11% C282Y/H63D, one (3% H63D/H63D, six (17% C282Y/WT and ten (29% H63D/WT. No patients had the S65C mutation and nine (25% did not present any of the three HFE mutations. Four out of five patients with C282Y/C282Y genotype (80% and three out of four patients with C282Y/H63D genotype (75% were HLA A*03. CONCLUSION: Analysis of HFE gene mutations constitutes an important procedure in identifying patients with hereditary hemochromatosis, particularly for patients with iron overload.

Evidence for the Influence of the Iron Regulatory MHC Class I Molecule HFE on Tumor Progression in Experimental Models and Clinical Populations

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Weston, Cody; Connor, James

2014-01-01

Proteins involved in iron regulation are modifiers of cancer risk and progression. Of these, the HFE protein (high iron gene and its protein product) is of particular interest because of its interaction with both iron handling and immune function and the high rate of genetic polymorphisms resulting in a mutant protein. Clinical studies suggest that HFE polymorphisms increase the risk of certain cancers, but the inconsistent outcomes suggest a more nuanced effect, possibly interacting with other genetic or environmental factors. Some basic science research has been conducted to begin to understand the implications of variant HFE genotype on cancer, but the story is far from complete. In particular, putative mechanisms exist for HFE to affect tumor progression through its role in iron handling and its major histocompatibility complex class I structural features. In this review, the current understanding of the role of HFE in cancer is described and models for future directions are identified. PMID:25520556

Implicating the H63D polymorphism in the HFE gene in increased incidence of solid cancers: a meta-analysis.

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Shen, L L; Gu, D Y; Zhao, T T; Tang, C J; Xu, Y; Chen, J F

2015-10-29

A number of previous studies have demonstrated that the HFE H63D polymorphism is associated with increased risk of incidence multiple types of cancer, including colorectal cancer, breast cancer, liver cancer, pancreatic cancer, and gynecological malignant tumors. However, the clinical outcomes were inconsistent. Therefore, this meta-analysis was conducted to summarize the effect of the H63D variant on the incidence of solid tumor. PubMed and EMBASE databases were searched for articles associating the HFE H63D polymorphism with cancer risk. The relationships were evaluated by calculating the pooled odds ratios (ORs) with 95% confidence intervals (CIs). A total of 28 studies, including 7728 cancer cases and 11,895 controls, were identified. Statistically significant associations were identified between the HFE H63D polymorphism and solid cancer risk (CG vs CC, OR = 1.14, 95%CI = 1.07-1.23, P HFE H63D polymorphism may play a critical role in the increased aggressiveness of hepatocellular carcinoma and pancreatic cancer.

Impact of HFE genetic testing on clinical presentation of hereditary hemochromatosis: new epidemiological data

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Ka Chandran

2005-06-01

Full Text Available Abstract Background Hereditary hemochromatosis (HH is a common inherited disorder of iron metabolism in Northern European populations. The discovery of a candidate gene in 1996 (HFE, and of its main mutation (C282Y, has radically altered the way to diagnose this disease. The aim of this study was to assess the impact of the HFE gene discovery on the clinical presentation and epidemiology of HH. Methods We studied our cohort of 415 patients homozygous for the C282Y allele and included in a phlebotomy program in a blood centre in western Brittany, France. Results In this cohort, 56.9% of the patients were male and 21.9% began their phlebotomy program before the implementation of the genetic test. A significant decrease in the sex ratio was noticed following implementation of this DNA test, from 3.79 to 1.03 (p -5, meaning that the proportion of diagnosed females relatives to males greatly increased. The profile of HH patients at diagnosis changed after the DNA test became available. Serum ferritin and iron values were lower and there was a reduced frequency of clinical signs displayed at diagnosis, particularly skin pigmentation (20.1 vs. 40.4%, OR = 0.37, p Conclusion This study highlights the importance of the HFE gene discovery, which has simplified the diagnosis of HH and modified its clinical presentation and epidemiology. This study precisely measures these changes. Enhanced diagnosis of HFE-related HH at an early stage and implementation of phlebotomy treatment are anticipated to maintain normal life expectancy for these patients.

Association between the HFE C282Y, H63D Polymorphisms and the Risks of Non-Alcoholic Fatty Liver Disease, Liver Cirrhosis and Hepatocellular Carcinoma: An Updated Systematic Review and Meta-Analysis of 5,758 Cases and 14,741 Controls

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Yin, Wei-Li; Wang, Feng-Mei; Han, Tao

2016-01-01

Background Conflicting results have been obtained for the association between two common polymorphisms (C282Y, H63D) of human HFE (hereditary hemochromatosis) gene and the risks of the liver diseases, including non-alcoholic fatty liver disease (NAFLD), liver cirrhosis and hepatocellular carcinoma (HCC). Methods An updated systematic review and meta-analysis was conducted to evaluate the potential role of HFE polymorphisms in the susceptibility to NAFLD, liver cirrhosis and HCC. After retrieving articles from online databases, eligible studies were enrolled according to the selection criteria. Stata/SE 12.0 software was utilized to perform the statistical analysis. Results In total, 43 articles with 5,758 cases and 14,741 controls were selected. Compared with the control group, a significantly increased risk of NAFLD was observed for the C282Y polymorphism in the Caucasian population under all genetic models and for the H63D polymorphism under the allele, heterozygote and dominant models (all OR>1, PassociationHFE C282Y and H63D (all Passociation>0.05). In addition, we found that HFE C282Y was statistically associated with increased HCC susceptibility in the overall population, while H63D increased the odds of developing non-cirrhotic HCC in the African population (all OR>1, PassociationHFE C282Y and H63D polymorphisms confer increased genetic susceptibility to NAFLD and HCC but not liver cirrhosis. Additional well-powered studies are required to confirm our conclusion. PMID:27657935

The Study of HFE Genotypes and Its Expression Effect on Iron Status of Iranian Haemochromatosis, Iron Deficiency Anemia Patients, Iron-Taker and Non Iron-Taker Controls.

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Beiranvand, Elham; Abediankenari, Saeid; Rostamian, Mosayeb; Beiranvand, Behnoush; Naazeri, Saeed

2015-01-01

The role of HFE gene mutations or its expression in regulation of iron metabolism of hereditary haemochromatosis (HH) patients is remained controversial. Therefore here the correlation between two common HFE genotype (p.C282Y, p.H63D) and HFE gene expression with iron status in HH, iron deficiency anemia (IDA) and healthy Iranian participants was studied. For this purpose genotype determination was done by polymerase chain reaction--restriction fragment length polymorphism (PCR-RFLP). Real-Time PCR was applied for evaluation of HFE gene expression. Biochemical parameters and iron consumption were also assessed. Homozygote p.H63D mutation was seen in all HH patients and p.C282Y was not observed in any member of the population. A significant correlation was observed between serum ferritin (SF) level and gender or age of HH patients. p.H63D homozygote was seen to be able to significantly increase SF and transferrin saturation (TS) level without affecting on liver function. Our results also showed that iron consumption affects on TS level increasing. HFE gene expression level of IDA patients was significantly higher than other groups. Also the HFE gene expression was negatively correlated with TS. Finally, the main result of our study showed that loss of HFE function in HH is not derived from its gene expression inhibition and much higher HFE gene expression might lead to IDA. However we propose repeating of the study for more approval of our finding.

Association study between four polymorphisms in the HFE, TF and TFR genes and Parkinson's disease in southern Italy.

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Greco, Valentina; De Marco, Elvira Valeria; Rocca, Francesca Emanuela; Annesi, Ferdinanda; Civitelli, Donatella; Provenzano, Giovanni; Tarantino, Patrizia; Scornaienchi, Vittorio; Pucci, Franco; Salsone, Maria; Novellino, Fabiana; Morelli, Maurizio; Paglionico, Sandra; Gambardella, Antonio; Quattrone, Aldo; Annesi, Grazia

2011-06-01

Iron overload may lead to neurodegenerative disorders such as Parkinson's disease (PD) and alterations of iron-related genes might be involved in the pathogenesis of this disease. The gene of haemochromatosis (HFE) encodes the HFE protein which interacts with the transferrin receptor (TFR), lowering its affinity for iron-bound transferrin (TF). We examined four known polymorphisms, C282Y and H63D in the HFE gene, G258S in the TF gene and S82G in the TFR gene, in 181 sporadic PD patients and 180 controls from Southern Italy to investigate their possible role in susceptibility to PD. No significant differences were found in genotype and allele frequencies between PD and controls for all the polymorphisms studied, suggesting that these variants do not contribute significantly to the risk of PD.

Mild iron overload in patients carrying the HFE S65C gene mutation: a retrospective study in patients with suspected iron overload and healthy controls

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Holmström, P; Marmur, J; Eggertsen, G; Gåfvels, M; Stål, P

2002-01-01

Background and aims: The role of the HFE S65C mutation in the development of hepatic iron overload is unknown. The aim of the present study was: (A) to determine the HFE S65C frequency in a Northern European population; and (B) to evaluate whether the presence of the HFE S65C mutation would result in a significant hepatic iron overload.

HFE C282Y/H63D compound heterozygotes are at low risk of hemochromatosis-related morbidity.

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Gurrin, Lyle C; Bertalli, Nadine A; Dalton, Gregory W; Osborne, Nicholas J; Constantine, Clare C; McLaren, Christine E; English, Dallas R; Gertig, Dorota M; Delatycki, Martin B; Nicoll, Amanda J; Southey, Melissa C; Hopper, John L; Giles, Graham G; Anderson, Gregory J; Olynyk, John K; Powell, Lawrie W; Allen, Katrina J

2009-07-01

The risk of hemochromatosis-related morbidity is unknown among HFE compound heterozygotes (C282Y/H63D). We used a prospective population-based cohort study to estimate the prevalence of elevated iron indices and hemochromatosis-related morbidity for compound heterozygotes. In all, 31,192 subjects of northern European descent were genotyped for HFE C282Y and H63D. An HFE-genotype stratified random sample of 1,438 subjects, followed for an average of 12 years to a mean age of 65 years, completed questionnaires and gave blood. Clinical examinations were blinded to HFE genotype. A total of 180 (84 males) clinically examined C282Y/H63D participants were compared with 330 (149 males) controls with neither HFE mutation; 132 (65 males) and 270 (122 males), respectively, had serum iron measures at both timepoints. Mean serum ferritin (SF) and transferrin saturation (TS) were significantly greater for male and female compound heterozygotes than for wild-types at baseline and follow-up (all P females who were premenopausal at baseline, where SF was similar in both genotype groups. For subjects with serum measures from both baseline and follow-up, mean SF and TS levels did not change significantly for men or for postmenopausal women, but for premenopausal women SF levels increased from 43 to 109 microg/L for compound heterozygotes and from 35 to 64 microg/L for wild-types (both P female compound heterozygotes had a similar prevalence of hemochromatosis-related morbidity to wild-types. One of 82 males and zero of 95 females had documented iron overload-related disease. For male compound heterozygotes, mean iron indices do not change during middle age but for female compound heterozygotes menopause results in increased mean SF. Although compound heterozygotes might maintain elevated iron indices during middle age, documented iron overload-related disease is rare.

Mutation in HFE gene decreases manganese accumulation and oxidative stress in the brain after olfactory manganese exposure.

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Ye, Qi; Kim, Jonghan

2016-06-01

Increased accumulation of manganese (Mn) in the brain is significantly associated with neurobehavioral deficits and impaired brain function. Airborne Mn has a high systemic bioavailability and can be directly taken up into the brain, making it highly neurotoxic. While Mn transport is in part mediated by several iron transporters, the expression of these transporters is altered by the iron regulatory gene, HFE. Mutations in the HFE gene are the major cause of the iron overload disorder, hereditary hemochromatosis, one of the prevalent genetic diseases in humans. However, whether or not HFE mutation modifies Mn-induced neurotoxicity has not been evaluated. Therefore, our goal was to define the role of HFE mutation in Mn deposition in the brain and the resultant neurotoxic effects after olfactory Mn exposure. Mice carrying the H67D HFE mutation, which is homologous to the H63D mutation in humans, and their control, wild-type mice, were intranasally instilled with MnCl2 with different doses (0, 0.2, 1.0 and 5.0 mg kg(-1)) daily for 3 days. Mn levels in the blood, liver and brain were determined using inductively-coupled plasma mass spectrometry (ICP-MS). H67D mutant mice showed significantly lower Mn levels in the blood, liver, and most brain regions, especially in the striatum, while mice fed an iron-overload diet did not. Moreover, mRNA expression of ferroportin, an essential exporter of iron and Mn, was up-regulated in the striatum. In addition, the levels of isoprostane, a marker of lipid peroxidation, were increased in the striatum after Mn exposure in wild-type mice, but were unchanged in H67D mice. Together, our results suggest that the H67D mutation provides decreased susceptibility to Mn accumulation in the brain and neurotoxicity induced by inhaled Mn.

A novel homozygous stop-codon mutation in human HFE responsible for nonsense-mediated mRNA decay.

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Padula, Maria Carmela; Martelli, Giuseppe; Larocca, Marilena; Rossano, Rocco; Olivieri, Attilio

2014-09-01

HFE-hemochromatosis (HH) is an autosomal disease characterized by excessive iron absorption. Homozygotes for H63D variant, and still less H63D heterozygotes, generally do not express HH phenotype. The data collected in our previous study in the province of Matera (Basilicata, Italy) underlined that some H63D carriers showed altered iron metabolism, without additional factors. In this study, we selected a cohort of 10/22 H63D carriers with severe biochemical iron overload (BIO). Additional analysis was performed for studying HFE exons, exon-intron boundaries, and untranslated regions (UTRs) by performing DNA extraction, PCR amplification and sequencing. The results showed a novel substitution (NM_000410.3:c.847C>T) in a patient exon 4 (GenBankJQ478433); it introduces a premature stop-codon (PTC). RNA extraction and reverse-transcription were also performed. Quantitative real-time PCR was carried out for verifying if our aberrant mRNA is targeted for nonsense-mediated mRNA decay (NMD); we observed that patient HFE mRNA was expressed much less than calibrator, suggesting that the mutated HFE protein cannot play its role in iron metabolism regulation, resulting in proband BIO. Our finding is the first evidence of a variation responsible for a PTC in iron cycle genes. The genotype-phenotype correlation observed in our cases could be related to the additional mutation. Copyright © 2014 Elsevier Inc. All rights reserved.

Two novel mutations in the SLC40A1 and HFE genes implicated in iron overload in a Spanish man.

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Del-Castillo-Rueda, Alejandro; Moreno-Carralero, María-Isabel; Alvarez-Sala-Walther, Luis-Antonio; Cuadrado-Grande, Nuria; Enríquez-de-Salamanca, Rafael; Méndez, Manuel; Morán-Jiménez, María-Josefa

2011-03-01

The most common form of hemochromatosis is caused by mutations in the HFE gene. Rare forms of the disease are caused by mutations in other genes. We present a patient with hyperferritinemia and iron overload, and facial flushing. Magnetic resonance imaging was performed to measure hepatic iron overload, and a molecular study of the genes involved in iron metabolism was undertaken. The iron overload was similar to that observed in HFE hemochromatosis, and the patient was double heterozygous for two novel mutations, c.-20G>A and c.718A>G (p.K240E), in the HFE and ferroportin (FPN1 or SLC40A1) genes, respectively. Hyperferritinemia and facial flushing improved after phlebotomy. Two of the patient's children were also studied, and the daughter was heterozygous for the mutation in the SLC40A1 gene, although she did not have hyperferritinemia. The patient presented a mild iron overload phenotype probably because of the two novel mutations in the HFE and SLC40A1 genes. © 2011 John Wiley & Sons A/S.

Examination of HFE associations with childhood leukemia risk and extension to other iron regulatory genes.

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Kennedy, Amy E; Kamdar, Kala Y; Lupo, Philip J; Okcu, M Fatih; Scheurer, Michael E; Baum, Marianna K; Dorak, M Tevfik

2014-09-01

Hereditary hemochromatosis (HFE) variants correlating with body iron levels have shown associations with cancer risk, including childhood acute lymphoblastic leukemia (ALL). Using a multi-ethnic sample of cases and controls from Houston, TX, we examined two HFE variants (rs1800562 and rs1799945), one transferrin receptor gene (TFRC) variant (rs3817672) and three additional iron regulatory gene (IRG) variants (SLC11A2 rs422982; TMPRSS6 rs855791 and rs733655) for their associations with childhood ALL. Being positive for either of the HFE variants yielded a modestly elevated odds ratio (OR) for childhood ALL risk in males (1.40, 95% CI=0.83-2.35), which increased to 2.96 (95% CI=1.29-6.80) in the presence of a particular TFRC genotype for rs3817672 (P interaction=0.04). The TFRC genotype also showed an ethnicity-specific association, with increased risk observed in non-Hispanic Whites (OR=2.54, 95% CI=1.05-6.12; P interaction with ethnicity=0.02). The three additional IRG SNPs all showed individual risk associations with childhood ALL in males (OR=1.52-2.60). A polygenic model based on the number of variant alleles in five IRG SNPs revealed a linear increase in risk among males with the increasing number of variants possessed (OR=2.0 per incremental change, 95% CI=1.29-3.12; P=0.002). Our results replicated previous HFE risk associations with childhood ALL in a US population and demonstrated novel associations for IRG SNPs, thereby strengthening the hypothesis that iron excess mediated by genetic variants contributes to childhood ALL risk. Copyright © 2014 Elsevier Ltd. All rights reserved.

[CCR5, CCR2, apoe, p53, ITGB3 and HFE gene polymorphism in Western Siberia long-livers].

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Ivanoshchuk, D E; Mikhaĭlova, S V; Kulikov, I V; Maksimov, V N; Voevoda, M I; Romashchenko, A G

2012-01-01

In order to estimate the distribution of some polymorphisms for the CCR5, CCR2, apoE, p53, ITGB3, and HFE genes in Russian long-livers from Western Siberia, a sample of 271 individuals (range 90-105 years) was examined. It was demonstrated that carriage of the delta32 polymorphism for the CCR5 gene, V64/polymorphism for the CCR2 gene, e2/e3/e4 for the apoE gene, L33P for the ITGB3 gene, as well as H63D and S65C polymorphisms for the HFE gene does not influence on predisposition to the longevity; carriage of the 282 Y allele for the HFE gene negatively influences on the longevity; carriage of the heterozygous genotype for the R72P polymorphism for the p53 gene correlates with the longevity of elderly people.

HFE gene variants, iron, and lipids: a novel connection in Alzheimer's disease.

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Ali-Rahmani, Fatima; Schengrund, Cara-Lynne; Connor, James R

2014-01-01

Iron accumulation and associated oxidative stress in the brain have been consistently found in several neurodegenerative diseases. Multiple genetic studies have been undertaken to try to identify a cause of neurodegenerative diseases but direct connections have been rare. In the iron field, variants in the HFE gene that give rise to a protein involved in cellular iron regulation, are associated with iron accumulation in multiple organs including the brain. There is also substantial epidemiological, genetic, and molecular evidence of disruption of cholesterol homeostasis in several neurodegenerative diseases, in particular Alzheimer's disease (AD). Despite the efforts that have been made to identify factors that can trigger the pathological events associated with neurodegenerative diseases they remain mostly unknown. Because molecular phenotypes such as oxidative stress, synaptic failure, neuronal loss, and cognitive decline, characteristics associated with AD, have been shown to result from disruption of a number of pathways, one can easily argue that the phenotype seen may not arise from a linear sequence of events. Therefore, a multi-targeted approach is needed to understand a complex disorder like AD. This can be achieved only when knowledge about interactions between the different pathways and the potential influence of environmental factors on them becomes available. Toward this end, this review discusses what is known about the roles and interactions of iron and cholesterol in neurodegenerative diseases. It highlights the effects of gene variants of HFE (H63D- and C282Y-HFE) on iron and cholesterol metabolism and how they may contribute to understanding the etiology of complex neurodegenerative diseases.

Effect of HFE gene polymorphism on sustained virological response in patients with chronic hepatitis C and elevated serum ferritin.

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Coelho-Borges, Silvia; Cheinquer, Hugo; Wolff, Fernando Herz; Cheinquer, Nelson; Krug, Luciano; Ashton-Prolla, Patricia

2012-01-01

Abnormal serum ferritin levels are found in approximately 20%-30% of the patients with chronic hepatitis C and are associated with a lower response rate to interferon therapy. To determine if the presence of HFE gene mutations had any effect on the sustained virological response rate to interferon based therapy in chronic hepatitis C patients with elevated serum ferritin. A total of 44 treatment naÏve patients with histologically demonstrated chronic hepatitis C, all infected with hepatitis C virus genotype non-1 (38 genotype 3; 6 genotype 2) and serum ferritin above 500 ng/mL were treated with interferon (3 MU, 3 times a week) and ribavirin (1.000 mg, daily) for 24 weeks. Sustained virological response was defined as negative qualitative HCV-RNA more than 24 weeks after the end of treatment. Serum HCV-RNA was measured by qualitative in house polymerase chain reaction with a limit of detection of 200 IU/mL. HFE gene mutation was detected using restriction-enzyme digestion with RsaI (C282Y mutation analysis) and BclI (H63D mutation analysis) in 16 (37%) patients, all heterozygous (11 H63D, 2 C282Y and 3 both). Sustained virological response was achieved in 0 of 16 patients with HFE gene mutations and 11 (41%) of 27 patients without HFE gene mutations (P = 0.002; exact Fisher test). Heterozigozity for H63D and/or C282Y HFE gene mutation predicts absence of sustained virological response to combination treatment with interferon and ribavirin in patients with chronic hepatitis C, non-1 genotype and serum ferritin levels above 500 ng/mL.

Frequency of the HFE C282Y and H63D mutations in Danish patients with clinical haemochromatosis initially diagnosed by phenotypic methods

DEFF Research Database (Denmark)

Milman, Nils; Koefoed, Pernille; Pedersen, Palle

2003-01-01

AIM: To assess the frequency of the C282Y and H63D mutations on the HFE gene in Danish patients with clinical hereditary haemochromatosis initially diagnosed by phenotypic methods. METHODS: In the period 1950-1985, an epidemiological survey in Denmark identified 179 patients with clinical...... diagnosis of clinical idiopathic haemochromatosis was made before blood samples were taken for HFE genotyping. The total series consisted of 58 patients (40 men and 18 women) with a median age of 60 yrs (range 18-74). HFE genotyping was performed by the polymerase chain reaction (PCR) technique. RESULTS...

Eighty percent of French sport winners in Olympic, World and Europeans competitions have mutations in the hemochromatosis HFE gene.

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Hermine, Olivier; Dine, Gérard; Genty, Vincent; Marquet, Laurie-Anne; Fumagalli, Gabriela; Tafflet, Muriel; Guillem, Flavia; Van Lierde, Françoise; Rousseaux-Blanchi, Marie-Philippe; Palierne, Christian; Lapostolle, Jean-Claude; Cervetti, Jean-Pierre; Frey, Alain; Jouven, Xavier; Noirez, Philippe; Toussaint, Jean-François

2015-12-01

The HFE gene encodes a protein involved in iron homeostasis; individuals with mutations in both alleles develop hemochromatosis. 27% of the French population is heterozygous for mutations in this gene. We found that 80% of the French athletes who won international competitions in rowing, Nordic skiing and judo display mutations in one allele of HFE, thus demonstrating the existence of a favourable phenotype linked to this heterozygosity. Copyright © 2015. Published by Elsevier B.V.

Sexo y diversidad funcional ¿Un tabú que se desmorona? La figura del asistente sexual

OpenAIRE

Ledesma Laguna, Paula

2017-01-01

A lo largo de los años, incluso aún en la actualidad, la sociedad asocia una serie de mitos y creencias a las personas con diversidad funcional, y más aún a la sexualidad de las mismas. Esto provoca un concepto erróneo sobre dicha dimensión, produciendo un efecto negativo, perjudicial y estigmatizador para este colectivo. La sexualidad se encuentra en la normativa como un derecho a la intimidad y al propio cuerpo, pero en la realidad, no sucede así. En este trabajo se hace un recorrido desde ...

Carriers of the Complex Allele HFE c.[187C>G;340+4T>C] Have Increased Risk of Iron Overload in São Miguel Island Population (Azores, Portugal).

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Branco, Claudia C; Gomes, Cidália T; De Fez, Laura; Bulhões, Sara; Brilhante, Maria José; Pereirinha, Tânia; Cabral, Rita; Rego, Ana Catarina; Fraga, Cristina; Miguel, António G; Brasil, Gracinda; Macedo, Paula; Mota-Vieira, Luisa

2015-01-01

Iron overload is associated with acquired and genetic conditions, the most common being hereditary hemochromatosis (HH) type-I, caused by HFE mutations. Here, we conducted a hospital-based case-control study of 41 patients from the São Miguel Island (Azores, Portugal), six belonging to a family with HH type-I pseudodominant inheritance, and 35 unrelated individuals fulfilling the biochemical criteria of iron overload compatible with HH type-I. For this purpose, we analyzed the most common HFE mutations- c.845G>A [p.Cys282Tyr], c.187C>G [p.His63Asp], and c.193A>T [p.Ser65Cys]. Results revealed that the family's HH pseudodominant pattern is due to consanguineous marriage of HFE-c.845G>A carriers, and to marriage with a genetically unrelated spouse that is a -c.187G carrier. Regarding unrelated patients, six were homozygous for c.845A, and three were c.845A/c.187G compound heterozygous. We then performed sequencing of HFE exons 2, 4, 5 and their intron-flanking regions. No other mutations were observed, but we identified the -c.340+4C [IVS2+4C] splice variant in 26 (74.3%) patients. Functionally, the c.340+4C may generate alternative splicing by HFE exon 2 skipping and consequently, a protein missing the α1-domain essential for HFE/ transferrin receptor-1 interactions. Finally, we investigated HFE mutations configuration with iron overload by determining haplotypes and genotypic profiles. Results evidenced that carriers of HFE-c.187G allele also carry -c.340+4C, suggesting in-cis configuration. This data is corroborated by the association analysis where carriers of the complex allele HFE-c.[187C>G;340+4T>C] have an increased iron overload risk (RR = 2.08, 95% CI = 1.40-2.94, poverload because they will produce two altered proteins--the p.63Asp [c.187G], and the protein lacking 88 amino acids encoded by exon 2. In summary, we provide evidence that the complex allele HFE-c.[187C>G;340+4T>C] has a role, as genetic predisposition factor, on iron overload in the S�

Effect of HFE gene polymorphism on sustained virological response in patients with chronic hepatitis C and elevated serum ferritin

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Silvia Coelho-Borges

2012-03-01

Full Text Available CONTEXT: Abnormal serum ferritin levels are found in approximately 20%-30% of the patients with chronic hepatitis C and are associated with a lower response rate to interferon therapy. OBJECTIVE: To determine if the presence of HFE gene mutations had any effect on the sustained virological response rate to interferon based therapy in chronic hepatitis C patients with elevated serum ferritin. METHODS: A total of 44 treatment naÏve patients with histologically demonstrated chronic hepatitis C, all infected with hepatitis C virus genotype non-1 (38 genotype 3; 6 genotype 2 and serum ferritin above 500 ng/mL were treated with interferon (3 MU, 3 times a week and ribavirin (1.000 mg, daily for 24 weeks. RESULTS: Sustained virological response was defined as negative qualitative HCV-RNA more than 24 weeks after the end of treatment. Serum HCV-RNA was measured by qualitative in house polymerase chain reaction with a limit of detection of 200 IU/mL. HFE gene mutation was detected using restriction-enzyme digestion with RsaI (C282Y mutation analysis and BclI (H63D mutation analysis in 16 (37% patients, all heterozygous (11 H63D, 2 C282Y and 3 both. Sustained virological response was achieved in 0 of 16 patients with HFE gene mutations and 11 (41% of 27 patients without HFE gene mutations (P = 0.002; exact Fisher test. CONCLUSION: Heterozigozity for H63D and/or C282Y HFE gene mutation predicts absence of sustained virological response to combination treatment with interferon and ribavirin in patients with chronic hepatitis C, non-1 genotype and serum ferritin levels above 500 ng/mL.

Clinical penetrance in hereditary hemochromatosis: estimates of the cumulative incidence of severe liver disease among HFE C282Y homozygotes.

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Grosse, Scott D; Gurrin, Lyle C; Bertalli, Nadine A; Allen, Katrina J

2018-04-01

Iron overload (hemochromatosis) can cause serious, symptomatic disease that is preventable if detected early and managed appropriately. The leading cause of hemochromatosis in populations of predominantly European ancestry is homozygosity of the C282Y variant in the HFE gene. Screening of adults for iron overload or associated genotypes is controversial, largely because of a belief that severe phenotypes are uncommon, although cascade testing of first-degree relatives of patients is widely endorsed. We contend that severe liver disease (cirrhosis or hepatocellular cancer) is not at all uncommon among older males with hereditary hemochromatosis. Our review of the published data from a variety of empirical sources indicates that roughly 1 in 10 male HFE C282Y homozygotes is likely to develop severe liver disease during his lifetime unless iron overload is detected early and treated. New evidence from a randomized controlled trial of treatment allows for evidence-based management of presymptomatic patients. Although population screening for HFE C282Y homozygosity faces multiple barriers, a potentially effective strategy for increasing the early detection and prevention of clinical iron overload and severe disease is to include HFE C282Y homozygosity in lists of medically actionable gene variants when reporting the results of genome or exome sequencing.

HFE gene variants, iron, and lipids: a novel connection in Alzheimer’s disease

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Ali-Rahmani, Fatima; Schengrund, Cara-Lynne; Connor, James R.

2014-01-01

Iron accumulation and associated oxidative stress in the brain have been consistently found in several neurodegenerative diseases. Multiple genetic studies have been undertaken to try to identify a cause of neurodegenerative diseases but direct connections have been rare. In the iron field, variants in the HFE gene that give rise to a protein involved in cellular iron regulation, are associated with iron accumulation in multiple organs including the brain. There is also substantial epidemiological, genetic, and molecular evidence of disruption of cholesterol homeostasis in several neurodegenerative diseases, in particular Alzheimer’s disease (AD). Despite the efforts that have been made to identify factors that can trigger the pathological events associated with neurodegenerative diseases they remain mostly unknown. Because molecular phenotypes such as oxidative stress, synaptic failure, neuronal loss, and cognitive decline, characteristics associated with AD, have been shown to result from disruption of a number of pathways, one can easily argue that the phenotype seen may not arise from a linear sequence of events. Therefore, a multi-targeted approach is needed to understand a complex disorder like AD. This can be achieved only when knowledge about interactions between the different pathways and the potential influence of environmental factors on them becomes available. Toward this end, this review discusses what is known about the roles and interactions of iron and cholesterol in neurodegenerative diseases. It highlights the effects of gene variants of HFE (H63D- and C282Y-HFE) on iron and cholesterol metabolism and how they may contribute to understanding the etiology of complex neurodegenerative diseases. PMID:25071582

The hepcidin gene promoter nc.-1010C > T; -582A > G haplotype modulates serum ferritin in individuals carrying the common H63D mutation in HFE gene.

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Silva, Bruno; Pita, Lina; Gomes, Susana; Gonçalves, João; Faustino, Paula

2014-12-01

Hereditary hemochromatosis is an autosomal recessive disorder characterized by severe iron overload. It is usually associated with homozygosity for the HFE gene mutation c.845G > A; p.C282Y. However, in some cases, another HFE mutation (c.187C > G; p.H63D) seems to be associated with the disease. Its penetrance is very low, suggesting the possibility of other iron genetic modulators being involved. In this work, we have screened for HAMP promoter polymorphisms in 409 individuals presenting normal or increased serum ferritin levels together with normal or H63D-mutated HFE genotypes. Our results show that the hepcidin gene promoter TG haplotype, originated by linkage of the nc.-1010C > T and nc.-582A > G polymorphisms, is more frequent in the HFE_H63D individuals presenting serum ferritin levels higher than 300 μg/L than in those presenting the HFE_H63D mutation but with normal serum ferritin levels or in the normal control group.Moreover, it was observed that the TG haplotype was associated to increased serum ferritin levels in the overall pool of HFE_H63D individuals. Thus, our data suggest that screening for these polymorphisms could be of interest in order to explain the phenotype. However, this genetic condition seems to have no clinical significance.

Liver steatosis correlates with iron overload but not with HFE gene mutations in chronic hepatitis C.

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Sikorska, Katarzyna; Stalke, Piotr; Romanowski, Tomasz; Rzepko, Robert; Bielawski, Krzysztof Piotr

2013-08-01

Liver steatosis and iron overload, which are frequently observed in chronic hepatitis C (CHC), may contribute to the progression of liver injury. This study aimed to evaluate the correlation between liver steatosis and iron overload in Polish patients with CHC compared to non-alcoholic fatty liver disease (NAFLD) and HFE-hereditary hemochromatosis (HH) patients. A total of 191 CHC patients were compared with 67 NAFLD and 21 HH patients. Liver function tests, serum markers of iron metabolism, cholesterol and triglycerides were assayed. The inflammatory activity, fibrosis, iron deposits and steatosis stages were assessed in liver specimens. HFE gene polymorphisms were investigated by PCR-RFLP. Liver steatosis was associated with obesity and diabetes mellitus. This disease was confirmed in 76/174 (44%) CHC patients, most of whom were infected with genotype 1. The average grade of steatosis was higher in NAFLD patients. CHC patients had significantly higher iron concentrations and transferrin saturations than NAFLD patients. Compared with CHC patients, HH patients had higher values of serum iron parameters and more intensive hepatocyte iron deposits without differences in the prevalence and intensity of liver steatosis. In the CHC group, lipids accumulation in hepatocytes was significantly associated with the presence of serum markers of iron overload. No correlation between the HFE gene polymorphism and liver steatosis in CHC patients was found. Liver steatosis was diagnosed in nearly half of CHC patients, most of whom were infected with genotype 1. The intensity of steatosis was lower in CHC patients than that in NAFLD patients because of a less frequent diagnosis of metabolic syndrome. Only in CHC patients were biochemical markers of iron accumulation positively correlated with liver steatosis; these findings were independent of HFE gene mutations.

Mutations in the HFE, TFR2, and SLC40A1 genes in patients with hemochromatosis.

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Del-Castillo-Rueda, Alejandro; Moreno-Carralero, María-Isabel; Cuadrado-Grande, Nuria; Alvarez-Sala-Walther, Luis-Antonio; Enríquez-de-Salamanca, Rafael; Méndez, Manuel; Morán-Jiménez, María-Josefa

2012-10-15

Hereditary hemochromatosis causes iron overload and is associated with a variety of genetic and phenotypic conditions. Early diagnosis is important so that effective treatment can be administered and the risk of tissue damage avoided. Most patients are homozygous for the c.845G>A (p.C282Y) mutation in the HFE gene; however, rare forms of genetic iron overload must be diagnosed using a specific genetic analysis. We studied the genotype of 5 patients who had hyperferritinemia and an iron overload phenotype, but not classic mutations in the HFE gene. Two patients were undergoing phlebotomy and had no iron overload, 1 with metabolic syndrome and no phlebotomy had mild iron overload, and 2 patients had severe iron overload despite phlebotomy. The patients' first-degree relatives also underwent the analysis. We found 5 not previously published mutations: c.-408_-406delCAA in HFE, c.1118G>A (p.G373D), c.1473G>A (p.E491E) and c.2085G>C (p.S695S) in TFR2; and c.-428_-427GG>TT in SLC40A1. Moreover, we found 3 previously published mutations: c.221C>T (p.R71X) in HFE; c.1127C>A (p.A376D) in TFR2; and c.539T>C (p.I180T) in SLC40A1. Four patients were double heterozygous or compound heterozygous for the mutations mentioned above, and the patient with metabolic syndrome was heterozygous for a mutation in the TFR2 gene. Our findings show that hereditary hemochromatosis is clinically and genetically heterogeneous and that acquired factors may modify or determine the phenotype. Copyright © 2012. Published by Elsevier B.V.

The effect of the hemochromatosis (HFE) genotype on lead load and iron metabolism among lead smelter workers.

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Fan, Guangqin; Du, Guihua; Li, Huijun; Lin, Fen; Sun, Ziyong; Yang, Wei; Feng, Chang; Zhu, Gaochun; Li, Yanshu; Chen, Ying; Jiao, Huan; Zhou, Fankun

2014-01-01

Both an excess of toxic lead (Pb) and an essential iron disorder have been implicated in many diseases and public health problems. Iron metabolism genes, such as the hemochromatosis (HFE) gene, have been reported to be modifiers for lead absorption and storage. However, the HFE gene studies among the Asian population with occupationally high lead exposure are lacking. To explore the modifying effects of the HFE genotype (wild-type, H63D variant and C282Y variant) on the Pb load and iron metabolism among Asian Pb-workers with high occupational exposure. Seven hundred and seventy-one employees from a lead smelter manufacturing company were tested to determine their Pb intoxication parameters, iron metabolic indexes and identify the HFE genotype. Descriptive and multivariate analyses were conducted. Forty-five H63D variant carriers and no C282Y variant carrier were found among the 771 subjects. Compared with subjects with the wild-type genotype, H63D variant carriers had higher blood lead levels, even after controlling for factors such as age, sex, marriage, education, smoking and lead exposure levels. Multivariate analyses also showed that the H63D genotype modifies the associations between the blood lead levels and the body iron burden/transferrin. No C282Y variant was found in this Asian population. The H63D genotype modified the association between the lead and iron metabolism such that increased blood lead is associated with a higher body iron content or a lower transferrin in the H63D variant. It is indicated that H63D variant carriers may be a potentially highly vulnerable sub-population if they are exposed to high lead levels occupationally.

Metabolic alterations, HFE gene mutations and atherogenic lipoprotein modifications in patients with primary iron overload.

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Meroño, Tomás; Brites, Fernando; Dauteuille, Carolane; Lhomme, Marie; Menafra, Martín; Arteaga, Alejandra; Castro, Marcelo; Saez, María Soledad; Ballerga, Esteban González; Sorroche, Patricia; Rey, Jorge; Lesnik, Philippe; Sordá, Juan Andrés; Chapman, M John; Kontush, Anatol; Daruich, Jorge

2015-05-01

Iron overload (IO) has been associated with glucose metabolism alterations and increased risk of cardiovascular disease (CVD). Primary IO is associated with mutations in the HFE gene. To which extent HFE gene mutations and metabolic alterations contribute to the presence of atherogenic lipoprotein modifications in primary IO remains undetermined. The present study aimed to assess small, dense low-density lipoprotein (LDL) levels, chemical composition of LDL and high-density lipoprotein (HDL) particles, and HDL functionality in IO patients. Eighteen male patients with primary IO and 16 sex- and age-matched controls were recruited. HFE mutations (C282Y, H63D and S65C), measures of insulin sensitivity and secretion (calculated from the oral glucose tolerance test), chemical composition and distribution profile of LDL and HDL subfractions (isolated by gradient density ultracentrifugation) and HDL functionality (as cholesterol efflux and antioxidative activity) were studied. IO patients compared with controls exhibited insulin resistance (HOMA-IR (homoeostasis model assessment-estimated insulin resistance): +93%, PHFE genotypes. C282Y homozygotes (n=7) presented a reduced β-cell function and insulin secretion compared with non-C282Y patients (n=11) (-58% and -73%, respectively, PHFE gene mutations are involved in the presence of atherogenic lipoprotein modifications in primary IO. To what extent such alterations could account for an increase in CVD risk remains to be determined.

The relationship between selected VDR, HFE and ALAD gene polymorphisms and several basic toxicological parameters among persons occupationally exposed to lead

International Nuclear Information System (INIS)

Szymańska-Chabowska, Anna; Łaczmański, Łukasz; Jędrychowska, Iwona; Chabowski, Mariusz; Gać, Paweł; Janus, Agnieszka; Gosławska, Katarzyna; Smyk, Beata; Solska, Urszula; Mazur, Grzegorz; Poręba, Rafał

2015-01-01

The aim of this study was to find a relationship between polymorphisms of ALAD rs1805313, rs222808, rs1139488, VDR FokI and HFE C282Y and H63D and basic toxicological parameters (lead and ZnPP blood concentration) in people occupationally exposed to lead. We collected data of 101 workers (age 25–63 years) directly exposed to lead. The toxicological lab tests included blood lead, cadmium and ZnPP concentration measurement and arsenic urine concentration measurement. Workers were genotyped for ALAD (rs1805313, rs222808, rs1139488), HFE (C282Y, H63D) and VDR (FokI). Individuals with the lead exposure and coexisting F allel in the locus Fok-I of VDR gene are suspected of higher zinc protoporphyrins concentrations. Workers exposed to the lead with the Y allel in the locus C282Y of the HFE gene are predisposed to lower ZnPP levels and individuals with coexisting H allel in the locus H63D HFE gene are predisposed to lower Pb-B levels. The T allel in the locus rs1805313 of the ALAD gene determines lower Pb-B and ZnPP levels in lead–exposed individuals. The heterozigosity of the locus rs2228083 of the ALAD gene has a strong predilection to higher Pb-B levels. The carriage of the C allel in the locus rs1139488 of the ALAD gene might determine higher Pb-B levels and the heterozigosity of the locus rs1139488 of the ALAD gene might result in higher ZnPP levels. Conclusion. The study revealed relationship between VDR, HFE and ALAD genes polymorphism and basic toxicological parameters in occupationally exposed workers

The effect of the hemochromatosis (HFE genotype on lead load and iron metabolism among lead smelter workers.

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Guangqin Fan

Full Text Available Both an excess of toxic lead (Pb and an essential iron disorder have been implicated in many diseases and public health problems. Iron metabolism genes, such as the hemochromatosis (HFE gene, have been reported to be modifiers for lead absorption and storage. However, the HFE gene studies among the Asian population with occupationally high lead exposure are lacking.To explore the modifying effects of the HFE genotype (wild-type, H63D variant and C282Y variant on the Pb load and iron metabolism among Asian Pb-workers with high occupational exposure.Seven hundred and seventy-one employees from a lead smelter manufacturing company were tested to determine their Pb intoxication parameters, iron metabolic indexes and identify the HFE genotype. Descriptive and multivariate analyses were conducted.Forty-five H63D variant carriers and no C282Y variant carrier were found among the 771 subjects. Compared with subjects with the wild-type genotype, H63D variant carriers had higher blood lead levels, even after controlling for factors such as age, sex, marriage, education, smoking and lead exposure levels. Multivariate analyses also showed that the H63D genotype modifies the associations between the blood lead levels and the body iron burden/transferrin.No C282Y variant was found in this Asian population. The H63D genotype modified the association between the lead and iron metabolism such that increased blood lead is associated with a higher body iron content or a lower transferrin in the H63D variant. It is indicated that H63D variant carriers may be a potentially highly vulnerable sub-population if they are exposed to high lead levels occupationally.

Genome-wide association study identifies TF as a significant modifier gene of iron metabolism in HFE hemochromatosis.

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de Tayrac, Marie; Roth, Marie-Paule; Jouanolle, Anne-Marie; Coppin, Hélène; le Gac, Gérald; Piperno, Alberto; Férec, Claude; Pelucchi, Sara; Scotet, Virginie; Bardou-Jacquet, Edouard; Ropert, Martine; Bouvet, Régis; Génin, Emmanuelle; Mosser, Jean; Deugnier, Yves

2015-03-01

Hereditary hemochromatosis (HH) is the most common form of genetic iron loading disease. It is mainly related to the homozygous C282Y/C282Y mutation in the HFE gene that is, however, a necessary but not a sufficient condition to develop clinical and even biochemical HH. This suggests that modifier genes are likely involved in the expressivity of the disease. Our aim was to identify such modifier genes. We performed a genome-wide association study (GWAS) using DNA collected from 474 unrelated C282Y homozygotes. Associations were examined for both quantitative iron burden indices and clinical outcomes with 534,213 single nucleotide polymorphisms (SNP) genotypes, with replication analyses in an independent sample of 748 C282Y homozygotes from four different European centres. One SNP met genome-wide statistical significance for association with transferrin concentration (rs3811647, GWAS p value of 7×10(-9) and replication p value of 5×10(-13)). This SNP, located within intron 11 of the TF gene, had a pleiotropic effect on serum iron (GWAS p value of 4.9×10(-6) and replication p value of 3.2×10(-6)). Both serum transferrin and iron levels were associated with serum ferritin levels, amount of iron removed and global clinical stage (pHFE-associated HH (HFE-HH) patients, identified the rs3811647 polymorphism in the TF gene as the only SNP significantly associated with iron metabolism through serum transferrin and iron levels. Because these two outcomes were clearly associated with the biochemical and clinical expression of the disease, an indirect link between the rs3811647 polymorphism and the phenotypic presentation of HFE-HH is likely. Copyright © 2014 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.

The relationship between selected VDR, HFE and ALAD gene polymorphisms and several basic toxicological parameters among persons occupationally exposed to lead.

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Szymańska-Chabowska, Anna; Łaczmański, Łukasz; Jędrychowska, Iwona; Chabowski, Mariusz; Gać, Paweł; Janus, Agnieszka; Gosławska, Katarzyna; Smyk, Beata; Solska, Urszula; Mazur, Grzegorz; Poręba, Rafał

2015-08-06

The aim of this study was to find a relationship between polymorphisms of ALAD rs1805313, rs222808, rs1139488, VDR FokI and HFE C282Y and H63D and basic toxicological parameters (lead and ZnPP blood concentration) in people occupationally exposed to lead. We collected data of 101 workers (age 25-63 years) directly exposed to lead. The toxicological lab tests included blood lead, cadmium and ZnPP concentration measurement and arsenic urine concentration measurement. Workers were genotyped for ALAD (rs1805313, rs222808, rs1139488), HFE (C282Y, H63D) and VDR (FokI). Individuals with the lead exposure and coexisting F allel in the locus Fok-I of VDR gene are suspected of higher zinc protoporphyrins concentrations. Workers exposed to the lead with the Y allel in the locus C282Y of the HFE gene are predisposed to lower ZnPP levels and individuals with coexisting H allel in the locus H63D HFE gene are predisposed to lower Pb-B levels. The T allel in the locus rs1805313 of the ALAD gene determines lower Pb-B and ZnPP levels in lead-exposed individuals. The heterozigosity of the locus rs2228083 of the ALAD gene has a strong predilection to higher Pb-B levels. The carriage of the C allel in the locus rs1139488 of the ALAD gene might determine higher Pb-B levels and the heterozigosity of the locus rs1139488 of the ALAD gene might result in higher ZnPP levels. The study revealed relationship between VDR, HFE and ALAD genes polymorphism and basic toxicological parameters in occupationally exposed workers. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Asociația Europeană a Profesorilor de Istorie EUROCLIO, La intersecția culturilor. Țările regiunii Marii Negre și schimbările politice din sec. XIX-XX, 2015

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Eugen Palade

2016-06-01

Full Text Available Review on two books - Asociația Europeană a Profesorilor de Istorie EUROCLIO, La intersecția culturilor. Țările regiunii Marii Negre și schimbările politice din sec. XIX-XX, 2015

MTHFR and HFE, but not preproghrelin and LBP, polymorphisms as risk factors for all-cause end-stage renal disease development.

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Bloudíčková, S; Kuthanová, L; Hubáček, J A

2014-01-01

End-stage renal disease (ESRD) is a serious health problem worldwide. The high prevalence of cardiovascular diseases and chronic inflammation remains a major cause of morbidity and mortality in haemodialysed patients. Beside some external factors, genetic predisposition both to renal failure and poor prognosis has been assumed. We have collected a total of 1,014 haemodialysed patients and 2,559 unrelated healthy Caucasians. Single-nucleotide polymorphisms (SNPs) in genes for preproghrelin (GHRL), lipopolysaccharide-binding protein (LBP), HFE and MTHFR were genotyped. In the group of patients, significantly more carriers presented the MTHFR T667T (P = 0.002) and HFE Asp63Asp (P = 0.001) and Cys282Cys (P = 0.01) genotypes. The frequencies of individual SNPs within GHRL and LBP genes did not differ between the patients and controls. The trends in genotype frequencies did not differ between the subgroups of patients with different time on haemodialysis. Common variants in MTHFR and HFE could be a risk factor for all-cause ESRD development, but are not predictors for the survival on haemodialysis.

Using iron studies to predict HFE mutations in New Zealand: implications for laboratory testing.

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O'Toole, Rebecca; Romeril, Kenneth; Bromhead, Collette

2017-04-01

The diagnosis of hereditary haemochromatosis (HH) is not straightforward because symptoms are often absent or non-specific. Biochemical markers of iron-overloading may be affected by other conditions. To measure the correlation between iron studies and HFE genotype to inform evidence-based recommendations for laboratory testing in New Zealand. Results from 2388 patients genotyped for C282Y, H63D and S65C in Wellington, New Zealand from 2007 to 2013 were compared with their biochemical phenotype as quantified by serum ferritin (SF), transferrin saturation (TS), serum iron (SI) and serum transferrin (ST). The predictive power of these markers was evaluated by receiver operator characteristic (ROC) curve analysis, and if a statistically significant association for a variable was seen, sensitivity, specificity and predictive values were calculated. Test ordering patterns showed that 62% of HFE genotyping tests were ordered because of an elevated SF alone and only 11% of these had a C-reactive protein test to rule out an acute phase reaction. The association between SF and significant HFE genotypes SF was low. However, TS values ≥45% predicted HH mutations with the highest sensitivity and specificity. A SF of >1000 µg/L was found in one at-risk patient (C282Y homozygote) who had a TS <45%. Our analysis highlights the need for clear guidelines for investigation of hyperferritinaemia and HH in New Zealand. Using our findings, we developed an evidence-based laboratory testing algorithm based on a TS ≥45%, a SF ≥1000 µg/L and/or a family history of HH which identified all C282Y homozygotes in this study. © 2016 Royal Australasian College of Physicians.

Frequency of the hemochromatosis HFE mutations C282Y, H63D, and S65C in blood donors in the Faroe Islands

DEFF Research Database (Denmark)

Milman, Nils; á Steig, Torkil; Koefoed, Pernille

2004-01-01

on the HFE gene was assessed by genotyping using the polymerase chain reaction (PCR) technique and calculated from direct allele counting. We found no C282Y homozygous subjects; 28 (14.0%) subjects were C282Y heterozygous and four subjects were C282Y/H63D compound heterozygous (2.0%). The C282Y allele......The aim of the study was to assess the frequencies of the hereditary hemochromatosis HFE mutations C282Y, H63D, and S65C in the population in the Faroe Islands. The series comprised 200 randomly selected blood donors of Faroese heritage. The frequency of the C282Y, H63D, and S65C mutations.......6%. Screening of larger groups of the Faroese population for HFE mutations especially C282Y should be considered in order to establish the penetrance....

Estudo das mutações C282Y, H63D e S65C do gene HFE em doentes brasileiros com sobrecarga de ferro Study of C282Y, H63D and S65C mutations in the HFE gene in Brazilian patients with iron overload

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Rodolfo D. Cançado

2007-12-01

Full Text Available Hemocromatose é uma das doenças genéticas mais freqüentes no ser humano e uma das causas mais importantes de sobrecarga de ferro. Os objetivos deste estudo foram determinar a freqüência das mutações C282Y, H63D e S65C do gene HFE em doentes brasileiros com sobrecarga de ferro, verificar a coexistência de anemia hemolítica hereditária, hepatite C e consumo excessivo de bebida alcoólica nestes doentes e avaliar a influência destas variáveis sobre os depósitos de ferro do organismo. Saturação da transferrina, ferritina sérica e análise das mutações C282Y, H63D e S65C do gene HFE, pelo método da PCR, foram determinadas em cinqüenta doentes com sobrecarga de ferro atendidos no Hemocentro da Santa Casa de São Paulo entre janeiro de 2000 e maio de 2004. A freqüência de mutação do gene HFE nos doentes com sobrecarga de ferro foi de 76,0% (38/50. Saturação da transferrina e ferritina foram significativamente maiores nos doentes homozigotos para a mutação C282Y confirmando a correlação entre genótipo C282Y/C282Y e maior risco de sobrecarga de ferro. A coexistência de hepatite C, consumo excessivo de bebida alcoólica ou anemia hemolítica hereditária estão implicados em aumento dos estoques de ferro e constituem fator de risco adicional em pacientes com mutação do gene HFE para a condição de sobrecarga de ferro.Hemochromatosis is one of the most frequent genetic diseases in humans and one of the most important causes of iron overload. The aims of this study were to determine the frequency of C282Y, H63D and S65C mutations of the HFE gene in Brazilian patients with iron overload, to verify the coexistence of chronic hemolytic anemia, hepatitis C and excessive alcohol consumption and to evaluate the influence of these variables on body iron deposits. Transferrin saturation, serum ferritin and C282Y, H63D and S65C HFE gene mutations (by PCR method were determined in 50 patients with iron overload in the Hemocentro da

Association between the HFE C282Y, H63D Polymorphisms and the Risks of Non-Alcoholic Fatty Liver Disease, Liver Cirrhosis and Hepatocellular Carcinoma: An Updated Systematic Review and Meta-Analysis of 5,758 Cases and 14,741 Controls.

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Qing Ye

Full Text Available Conflicting results have been obtained for the association between two common polymorphisms (C282Y, H63D of human HFE (hereditary hemochromatosis gene and the risks of the liver diseases, including non-alcoholic fatty liver disease (NAFLD, liver cirrhosis and hepatocellular carcinoma (HCC.An updated systematic review and meta-analysis was conducted to evaluate the potential role of HFE polymorphisms in the susceptibility to NAFLD, liver cirrhosis and HCC. After retrieving articles from online databases, eligible studies were enrolled according to the selection criteria. Stata/SE 12.0 software was utilized to perform the statistical analysis.In total, 43 articles with 5,758 cases and 14,741 controls were selected. Compared with the control group, a significantly increased risk of NAFLD was observed for the C282Y polymorphism in the Caucasian population under all genetic models and for the H63D polymorphism under the allele, heterozygote and dominant models (all OR>1, Passociation0.05. In addition, we found that HFE C282Y was statistically associated with increased HCC susceptibility in the overall population, while H63D increased the odds of developing non-cirrhotic HCC in the African population (all OR>1, Passociation<0.05. Moreover, a positive association between compound heterozygosity for C282Y/H63D and the risk of NAFLD and HCC, but not liver cirrhosis, was observed.Our meta-analysis provides evidence that the HFE C282Y and H63D polymorphisms confer increased genetic susceptibility to NAFLD and HCC but not liver cirrhosis. Additional well-powered studies are required to confirm our conclusion.

[Analysis of H63D mutation in hemochromatosis (HFE) gene in populations of central Eurasia].

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Khusainova, R I; Khusnutdinova, N N; Litvinov, S S; Khusnutdinova, E K

2013-02-01

An analysis of the frequency of H63D (c. 187C>G) mutations in the HFEgene in 19 populations from Central Eurasia demonstrated that the distribution of the mutation in the region of interest was not uniform and that there were the areas of H63D accumulation. The investigation of three polymorphic variants, c.340+4T>C (rs2071303, IVS2(+4)T>C), c.893-44T>C (rs1800708, IVS4(-44)T>C), and c.1007-47G>A (rs1572982, IVS5(-47)A>G), in the HFE gene in individuals homozygous for H63D mutations in the HFE gene revealed the linkage of H63D with three haplotypes, *CTA, *TG, and *TTA. These findings indicated the partial spread of the mutation in Central Eurasia from Western Europe, as well as the possible repeated appearance of the mutation on the territory on interest.

Variation in the HFE gene is associated with the development of bleomycin-induced pulmonary toxicity in testicular cancer patients.

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van der Schoot, Gabriela G F; Westerink, Nico-Derk L; Lubberts, Sjoukje; Nuver, Janine; Zwart, Nynke; Walenkamp, Annemiek M E; Wempe, Johan B; Meijer, Coby; Gietema, Jourik A

2016-05-01

Bleomycin and cisplatin are of key importance in testicular cancer treatment. Known potential serious adverse effects are bleomycin-induced pulmonary toxicity (BIP) and cisplatin-induced renal toxicity. Iron handling may play a role in development of this toxicity. Carriage of allelic variants of the HFE gene induces altered iron metabolism and may contribute to toxicity. We investigated the association between two common allelic variants of the HFE gene, H63D and C282Y, with development of pulmonary and renal toxicity during and after treatment with bleomycin- and cisplatin-containing chemotherapy. In 369 testicular cancer patients treated with bleomycin and cisplatin at the University Medical Center Groningen between 1978 and 2006, H63D and/or C282Y genotypes were determined with an allelic discrimination assay. Data were collected on development of BIP, pulmonary function parameters, renal function, and survival. BIP developed more frequently in patients who were heterozygote (16 in 75, 21%) and homozygote (2 in 4, 50%) for the H63D variant, compared with those who had the HFE wild-type gene (31 in 278, 11%) (p = 0.012). Overall survival, testicular cancer-related survival, and change in renal function were not associated with the H63D variant. We observed an association between presence of one or both H63D alleles and development of BIP in testicular cancer patients treated with bleomycin combination chemotherapy. In patients heterozygote and homozygote for the H63D variant, BIP occurred more frequently compared with wild-type patients. When validated and confirmed, HFE H63D genotyping may be used to identify patients with increased risk for pulmonary bleomycin toxicity. Copyright © 2016 Elsevier Ltd. All rights reserved.

HFE gene C282Y, H63D and S65C mutations frequency in the Transylvania region, Romania.

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Trifa, Adrian P; Popp, Radu A; Militaru, Mariela S; Farcaş, Marius F; Crişan, Tania O; Gana, Ionuţ; Cucuianu, Andrei; Pop, Ioan V

2012-06-01

HFE-associated haemochromatosis is one of the most frequent autosomal recessive disorders in the Caucasian population. Although most of the cases are homozygous individuals for the C282Y mutation, another two mutations, H63D and S65C, have been reported to be associated with milder forms of the disease. This study was a first attempt to evaluate the distribution of these HFE gene mutations in the Transylvania region. Two-hundred and twenty-five healthy, unrelated volunteers originating from the Transylvania region, Romania, were screened for the HFE gene C282Y, H63D and S65C mutations, using molecular genetics assays (Polymerase Chain Reaction-Restriction Fragments Length Polymorphism). For the C282Y mutation, 7 heterozygotes (3.1%) were found, but no homozygous individual. In the case of the H63D mutation, 40 heterozygotes (17.8%) and 4 homozygotes (1.75%) for the mutant allele were evidenced. We found a compound heterozygous genotype (C282Y/H63D) in one individual (0.45%). Thus, the allele frequencies of the C282Y and H63D were 1.75% and 10.9%, respectively. Three individuals (1.3%) were found to harbour the S65C mutation in a heterozygous state, but none in a homozygous state: the allele frequency of the mutant allele was 0.75%. The distribution of the HFE gene C282Y, H63D and S65C mutations found in our group matches the tendencies observed in other European countries: a decreasing gradient from Northern to Southern Europe for the C282Y mutation; high frequency for the H63D mutation, and low frequency for the S65C mutation in most of the countries.

Lack of evidence for the pathogenic role of iron and HFE gene mutations in Brazilian patients with nonalcoholic steatohepatitis

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M.M. Deguti

2003-06-01

Full Text Available The hypothesis of the role of iron overload associated with HFE gene mutations in the pathogenesis of nonalcoholic steatohepatitis (NASH has been raised in recent years. In the present study, biochemical and histopathological evidence of iron overload and HFE mutations was investigated in NASH patients. Thirty-two NASH patients, 19 females (59%, average 49.2 years, 72% Caucasians, 12% Mulattoes and 12% Asians, were submitted to serum aminotransferase and iron profile determinations. Liver biopsies were analyzed for necroinflammatory activity, architectural damage and iron deposition. In 31 of the patients, C282Y and H63D mutations were tested by PCR-RFLP. Alanine aminotransferase levels were increased in 30 patients, 2.42 ± 1.12 times the upper normal limit on average. Serum iron concentration, transferrin saturation and ferritin averages were 99.4 ± 31.3 g/dl, 33.1 ± 12.7% and 219.8 ± 163.8 µg/dl, respectively, corresponding to normal values in 93.5, 68.7 and 78.1% of the patients. Hepatic siderosis was observed in three patients and was not associated with architectural damage (P = 0.53 or with necroinflammatory activity (P = 0.27. The allelic frequencies (N = 31 found were 1.6 and 14.1% for C282Y and H63D, respectively, which were compatible with those described for the local population. In conclusion, no evidence of an association of hepatic iron overload and HFE mutations with NASH was found. Brazilian NASH patients comprise a heterogeneous group with many associated conditions such as hyperinsulinism, environmental hepatotoxin exposure and drugs, but not hepatic iron overload, and their disease susceptibility could be related to genetic and environmental features other than HFE mutations.

Hemocromatosis gene (HFE) mutations in patients with type 2 diabetes and their control group in an Iranian population

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Sharifi, F.; Esmaeilzadeh, A.; Zali, M.

2008-01-01

Objective was to assess the frequency of 2 different forms of hemochromatosis HFE gene mutations c282y and H63D mutations in a normal population in comparison with type 2 diabetic patients. This case control study was undertaken in Zanjan Diabetic Care Center, Zanjan, western Tehran, in 2005. Two hundred and two individuals were included in this study: 101 type 2 diabetes mellitus T2DM patients and 101 age and gender-matched controls. The patients were examined for mutations in the HFE gene. Nucleotide 845 C282Y and 187 H63D alleles were amplified by polymerase chain reaction PCR with lymphocyte deoxyribonucleic acid. The PCR products were analyzed by restriction enzyme digestion. Chi-square students test and Fisher's exact tests were used for comparison and odds ratio was calculated. Two hundred and two individuals were studied. The frequency of wild /C28Y alleles was 68.3/31.7% in diabetics p=0.08 and 73.4/26.3% in control subjects p=0.08. The distribution of genotypes was not statistically different. Based on our data, HFE mutations were not found in excess in patients with T2DM and there was no evidence that a population-based search for an excess of these alleles in type 2 diabetes was indicated. (author)

HFE p.C282Y homozygosity predisposes to rapid serum ferritin rise after menopause: A genotype-stratified cohort study of hemochromatosis in Australian women.

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Warne, Charles D; Zaloumis, Sophie G; Bertalli, Nadine A; Delatycki, Martin B; Nicoll, Amanda J; McLaren, Christine E; Hopper, John L; Giles, Graham G; Anderson, Greg J; Olynyk, John K; Powell, Lawrie W; Allen, Katrina J; Gurrin, Lyle C

2017-04-01

Women who are homozygous for the p.C282Y mutation in the HFE gene are at much lower risk of iron overload-related disease than p.C282Y homozygous men, presumably because of the iron-depleting effects of menstruation and pregnancy. We used data from a population cohort study to model the impact of menstruation cessation at menopause on serum ferritin (SF) levels in female p.C282Y homozygotes, with p.C282Y/p.H63D simple or compound heterozygotes and those with neither p.C282Y nor p.H63D mutations (HFE wild types) as comparison groups. A sample of the Melbourne Collaborative Cohort Study was selected for the "HealthIron" study (n = 1438) including all HFE p.C282Y homozygotes plus a random sample stratified by HFE-genotype (p.C282Y and p.H63D). The relationship between the natural logarithm of SF and time since menopause was examined using linear mixed models incorporating spline smoothing. For p.C282Y homozygotes, SF increased by a factor of 3.6 (95% CI (1.8, 7.0), P HFE genotype groups increase more gradually and did not show a distinction between premenopausal and postmenopausal SF levels. Only p.C282Y homozygotes had predicted SF exceeding 200 μg/L postmenopause, but the projected SF did not increase the risk of iron overload-related disease. These data provide the first documented evidence that physiological blood loss is a major factor in determining the marked gender difference in expression of p.C282Y homozygosity. © 2016 Journal of Gastroenterology and Hepatology Foundation and John Wiley & Sons Australia, Ltd.

La hiponatremia como marcador de riesgo en pacientes sometidos a implante de desfibrilador en prevención primaria

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Ana Andrés Lahuerta

2016-01-01

Conclusiones: La hiponatremia ligera en el momento del implante de un desfibrilador se asocia a una mayor incidencia de ingreso por insuficiencia cardiaca en el seguimiento, mientras que en el caso de una hiponatremia moderada-severa, se asocia a un riesgo de muerte 4 veces mayor.

Transferrin Level Before Treatment and Genetic Polymorphism in HFE Gene as Predictive Markers for Response to Adalimumab in Crohn's Disease Patients.

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Repnik, Katja; Koder, Silvo; Skok, Pavel; Ferkolj, Ivan; Potočnik, Uroš

2016-08-01

Tumor necrosis factor α inhibitors (anti-TNF) have improved treatment of several complex diseases, including Crohn's disease (CD). However, the effect varies and approximately one-third of the patients do not respond. Since blood parameters as well as genetic factors have shown a great potential to predict response during treatment, the aim of the study was to evaluate response to anti-TNF treatment with adalimumab (ADA) between genes HFE and TF and haematological parameters in Slovenian refractory CD patients. Single nucleotide polymorphisms (SNPs) rs1799852 in gene TF and rs2071303 in gene HFE were genotyped in 68 refractory CD patients for which response has been measured using inflammatory bowel disease questionnaire (IBDQ) index. Haematological parameters and IBDQ index were determined before therapy and after 4, 12, 20 and 30 weeks. We found novel strong association between SNP rs2071303 in gene HFE and response to ADA treatment, particularly patients with G allele comparing to A allele had better response after 20 weeks (p = 0.008). Further, we found strong association between transferrin level at baseline and treatment response after 12, 20 and 30 weeks, where average transferrin level before therapy was lower in responders (2.38 g/L) compared to non-responders (2.89 g/L, p = 0.005). Association was found between transferrin level in week 30 and SNP rs1799852 (p = 0.023), and between MCHC level before treatment and SNP rs2071303 (p = 0.007). Our results suggest that SNP in gene HFE as well as haematological markers serve as promising prognostic markers of response to anti-TNF treatment in CD patients.

Differing impact of the deletion of hemochromatosis-associated molecules HFE and transferrin receptor-2 on the iron phenotype of mice lacking bone morphogenetic protein 6 or hemojuvelin.

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Latour, Chloé; Besson-Fournier, Céline; Meynard, Delphine; Silvestri, Laura; Gourbeyre, Ophélie; Aguilar-Martinez, Patricia; Schmidt, Paul J; Fleming, Mark D; Roth, Marie-Paule; Coppin, Hélène

2016-01-01

Hereditary hemochromatosis, which is characterized by inappropriately low levels of hepcidin, increased dietary iron uptake, and systemic iron accumulation, has been associated with mutations in the HFE, transferrin receptor-2 (TfR2), and hemojuvelin (HJV) genes. However, it is still not clear whether these molecules intersect in vivo with bone morphogenetic protein 6 (BMP6)/mothers against decapentaplegic (SMAD) homolog signaling, the main pathway up-regulating hepcidin expression in response to elevated hepatic iron. To answer this question, we produced double knockout mice for Bmp6 and β2-microglobulin (a surrogate for the loss of Hfe) and for Bmp6 and Tfr2, and we compared their phenotype (hepcidin expression, Bmp/Smad signaling, hepatic and extrahepatic tissue iron accumulation) with that of single Bmp6-deficient mice and that of mice deficient for Hjv, alone or in combination with Hfe or Tfr2. Whereas the phenotype of Hjv-deficient females was not affected by loss of Hfe or Tfr2, that of Bmp6-deficient females was considerably worsened, with decreased Smad5 phosphorylation, compared with single Bmp6-deficient mice, further repression of hepcidin gene expression, undetectable serum hepcidin, and massive iron accumulation not only in the liver but also in the pancreas, the heart, and the kidneys. These results show that (1) BMP6 does not require HJV to transduce signal to hepcidin in response to intracellular iron, even if the loss of HJV partly reduces this signal, (2) another BMP ligand can replace BMP6 and significantly induce hepcidin expression in response to extracellular iron, and (3) BMP6 alone is as efficient at inducing hepcidin as the other BMPs in association with the HJV/HFE/TfR2 complex; they provide an explanation for the compensatory effect of BMP6 treatment on the molecular defect underlying Hfe hemochromatosis in mice. © 2015 by the American Association for the Study of Liver Diseases.

Estudio de la deficiencia de hierro en pacientes con insuficiencia cardiaca congestiva: una práctica clínica que precisa mayor atención

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Lara Belmar Vega

2016-05-01

Conclusión: La ICC se asocia con alta frecuencia a anemia, deficiencia de hierro e insuficiencia renal. El estudio de los parámetros férricos en los pacientes que ingresan con ICC, pese a que la corrección de la deficiencia de hierro se asocia a mejoría de la sintomatología, no se realiza con la frecuencia necesaria.

Sample-to-SNP kit: a reliable, easy and fast tool for the detection of HFE p.H63D and p.C282Y variations associated to hereditary hemochromatosis.

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Nielsen, Peter B; Petersen, Maja S; Ystaas, Viviana; Andersen, Rolf V; Hansen, Karin M; Blaabjerg, Vibeke; Refstrup, Mette

2012-10-01

Classical hereditary hemochromatosis involves the HFE-gene and diagnostic analysis of the DNA variants HFE p.C282Y (c.845G>A; rs1800562) and HFE p.H63D (c.187C>G; rs1799945). The affected protein alters the iron homeostasis resulting in iron overload in various tissues. The aim of this study was to validate the TaqMan-based Sample-to-SNP protocol for the analysis of the HFE-p.C282Y and p.H63D variants with regard to accuracy, usefulness and reproducibility compared to an existing SNP protocol. The Sample-to-SNP protocol uses an approach where the DNA template is made accessible from a cell lysate followed by TaqMan analysis. Besides the HFE-SNPs other eight SNPs were used as well. These SNPs were: Coagulation factor II-gene F2 c.20210G>A, Coagulation factor V-gene F5 p.R506Q (c.1517G>A; rs121917732), Mitochondria SNP: mt7028 G>A, Mitochondria SNP: mt12308 A>G, Proprotein convertase subtilisin/kexin type 9-gene PCSK9 p.R46L (c.137G>T), Plutathione S-transferase pi 1-gene GSTP1 p.I105V (c313A>G; rs1695), LXR g.-171 A>G, ZNF202 g.-118 G>T. In conclusion the Sample-to-SNP kit proved to be an accurate, reliable, robust, easy to use and rapid TaqMan-based SNP detection protocol, which could be quickly implemented in a routine diagnostic or research facility. Copyright © 2012. Published by Elsevier B.V.

The influence of iron status and genetic polymorphisms in the HFE gene on the risk for postoperative complications after bariatric surgery: a prospective cohort study in 1,064 patients

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Freedman-Weiss Mollie

2011-01-01

Full Text Available Abstract Background Gastric bypass surgery is a highly effective therapy for long-term weight loss in severely obese patients, but carries significant perioperative risks including infection, wound dehiscence, and leaks from staple breakdown. Iron status can affect immune function and wound healing, thus may influence peri-operative complications. Common mutations in the HFE gene, the gene responsible for the iron overload disorder hereditary hemochromatosis, may impact iron status. Methods We analyzed 1064 extremely obese Caucasian individuals who underwent open and laparoscopic Roux-n-Y gastric bypass surgery at the Geisinger Clinic. Serum iron, ferritin, transferrin, and iron binding capacity were measured pre-operatively. All patients had intra-operative liver biopsies and were genotyped for the C282Y and H63D mutations in the HFE gene. Associations between surgical complications and serum iron measures, HFE gene status, and liver iron histology were determined. Results We found that increased serum iron and transferrin saturation were present in patients with any post-operative complication, and that increased serum ferritin was also increased in patients with major complications. Increased serum transferrin saturation was also associated with wound complications in open RYGB, and transferrin saturation and ferritin with prolonged lengths of stay. The presence of 2 or more HFE mutations was associated with overall complications as well as wound complications in open RYGB. No differences were found in complication rates between those with stainable liver iron and those without. Conclusion Serum iron status and HFE genotype may be associated with complications following RYGB surgery in the extremely obese.

Mutations in the HFE gene and sporadic amyotrophic lateral sclerosis risk: a meta-analysis of observational studies

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M. Li

2014-03-01

Full Text Available Iron homeostasis dysregulation has been regarded as an important mechanism in neurodegenerative diseases. The H63D and C282Y polymorphisms in the HFE gene may be involved in the development of sporadic amyotrophic lateral sclerosis (ALS through the disruption of iron homeostasis. However, studies investigating the relationship between ALS and these two polymorphisms have yielded contradictory outcomes. We performed a meta-analysis to assess the roles of the H63D and C282Y polymorphisms of HFE in ALS susceptibility. PubMed, MEDLINE, EMBASE, and Cochrane Library databases were systematically searched to identify relevant studies. Strict selection criteria and exclusion criteria were applied. Odds ratios (ORs with 95% confidence intervals (CIs were used to assess the strength of associations. A fixed- or random-effect model was selected, depending on the results of the heterogeneity test. Fourteen studies were included in the meta-analysis (six studies with 1692 cases and 8359 controls for C282Y; 14 studies with 5849 cases and 13,710 controls for H63D. For the C282Y polymorphism, significant associations were observed in the allele model (Y vs C: OR=0.76, 95%CI=0.62-0.92, P=0.005 and the dominant model (YY+CY vs CC: OR=0.75, 95%CI=0.61-0.92, P=0.006. No associations were found for any genetic model for the H63D polymorphism. The C282Y polymorphism in HFE could be a potential protective factor for ALS in Caucasians. However, the H63D polymorphism does not appear to be associated with ALS.

White blood cells and subtypes in HFE p.C282Y and wild-type homozygotes in the Hemochromatosis and Iron Overload Screening Study.

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Barton, James C; Barton, J Clayborn; Acton, Ronald T

2017-03-01

The major histocompatibility complex is linked to white blood cell (WBC) and lymphocyte counts in subjects unselected for HFE genotypes. We compared age, sex, body mass index, total WBC and subtypes (neutrophils, lymphocytes, monocytes, eosinophils, basophils) (Beckman Coulter® Gen-S), transferrin saturation, and serum ferritin of HFE p.C282Y and wild-type (p.C282Y, p.H63D negative) homozygotes without acquired conditions that influence WBC counts. We performed regressions on WBC and subtypes. There were 161 p.C282Y homozygotes (45.3% men) and 221 wild-type homozygotes (40.3% men). Mean WBC of men and women and between HFE genotypes were similar. Mean lymphocytes were higher in male p.C282Y homozygotes: 1.6×10 9 /L [95% confidence interval: 1.5,1.7] vs. 1.4 [1.3,1.5], p=0.0002. Mean lymphocytes and basophils were higher in female p.C282Y homozygotes: 1.6 [1.5,1.7] vs. 1.4 [1.3,1.5], p=0.0002; and 0.065 [0.059,0.071] vs. 0.052 [0.051,0.054], p=0.0001, respectively. Transferrin saturation was associated with neutrophils (negative; p=0.0163). Age was associated with lymphocytes (negative; p=0.0003) and monocytes (positive; p<0.0001). Regressions on lymphocytes and basophils revealed positive associations with p.C282Y homozygosity (p=0.0043 and 0.0003, respectively). There were significant positive associations of neutrophils, lymphocytes, monocytes, and eosinophils. We conclude that HFE p.C282Y homozygosity is significantly associated with lymphocyte and basophil counts. Copyright © 2016 Elsevier Inc. All rights reserved.

Frequency of the Hemochromatosis Gene (HFE Variants in a Jordanian Arab Population and in Diabetics from the Same Region

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Asem Alkhateeb

2009-01-01

Full Text Available Hereditary HFE-linked hemochromatosis is a frequent recessive disorder among individuals of northern European ancestry. The clinical characteristic of this disease is the gradual accumulation of iron in internal organs, which ultimately may lead to organ damage and death. Three allelic variants of HFE gene have been correlated with hereditary hemochromatosis: C282Y is significantly associated with hereditary hemochromatosis in populations of Celtic origin, H63D and S65C are associated with milder form of iron overload. In this study we performed mutation analysis to identify allele frequency of the three variants of HFE gene in Jordanian Arab population, to assess deviations of these frequencies from those detected elsewhere, and to determine if there is an increased frequency of these variants in a diabetic population (Type 2 diabetes from the same area. DNA was extracted from blood samples of 440 individuals attending King Abdullah University Hospital for ambulatory services. We used polymerase chain reaction (PCR to amplify exons 2 and 4 of the HFE gene then restriction fragment length polymorphism (RFLP method to detect the variants. There were neither homozygous nor heterozygous for C282Y variant. For the H63D variant, 0.68% were homozygous and 21.1% were heterozygous. For the S65C variant, there were no homozygous and 0.23% were heterozygous. Allelic frequencies were, 0%, 11.25%, and 0.11% for C282Y, H63D, and S65C, respectively. Our samples were subdivided into two categories of type 2 diabetic (89 cases and controls (blood donors, 204 cases and compared with regard to the H63D variant. Both groups did not have homozygous H63D variant. H63D heterozygous in diabetics were 23.60% and in blood donor controls 22.55%. Allelic frequency of the mutant H63D allele was 11.80% in diabetics and 11.27% for the blood donor controls. This is the first study to show the frequency of the three hemochromatosis gene variants in Jordan with the interesting

Association of HFE gene C282Y and H63D mutations with liver cirrhosis in the Lithuanian population

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Simonas Juzėnas

2016-01-01

Conclusions: Heterozygous C282Y mutation of the HFE gene was associated with liver cirrhosis in the Lithuanian population. In gender-related analysis, heterozygous C282Y and homozygous H63D mutations were linked to liver cirrhosis in men, not in women.

HFE gene mutation and oxidative damage biomarkers in patients with myelodysplastic syndromes and its relation to transfusional iron overload: an observational cross-sectional study.

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De Souza, Geane Felix; Ribeiro, Howard Lopes; De Sousa, Juliana Cordeiro; Heredia, Fabíola Fernandes; De Freitas, Rivelilson Mendes; Martins, Manoel Ricardo Alves; Gonçalves, Romélia Pinheiro; Pinheiro, Ronald Feitosa; Magalhães, Silvia Maria Meira

2015-04-03

A relation between transfusional IOL (iron overload), HFE status and oxidative damage was evaluated. An observational cross-sectional study involving 87 healthy individuals and 78 patients with myelodysplastic syndromes (MDS) with and without IOL, seen at University Hospital of the Federal University of Ceará, Brazil, between May 2010 and September 2011. IOL was defined using repeated measures of serum ferritin ≥1000 ng/mL. Variations in the HFE gene were investigated using PCR/restriction fragment length polymorphism (RFLP). The biomarkers of oxidative stress (plasmatic malonaldehyde (MDA), glutathione peroxidase (GPx) and superoxide dismutase (SOD)) were determined by spectrophotometry. The HFE gene variations were identified in 24 patients (30.77%) and 5 volunteers (5.74%). The H63D variant was observed in 35% and the C282Y variant as heterozygous in 5% of patients with MDS with IOL. One patient showed double heterozygous variant (C282Y/H63D) and serum ferritin of 11,649 ng/mL. In patients without IOL, the H63D variant was detected in 29.34%. Serum MDA levels were highest in patients with MDS with IOL, with a significant difference when compared with patients without IOL and healthy volunteers, pointing to the relationship between IOL and oxidative stress. The GPx and SOD were also significantly higher in these patients, indicating that lipid peroxidation increase was followed by an increase in antioxidant capacity. Higher ferritin levels were observed in patients with HFE gene variation. 95.7% of patients with MDS with the presence of HFE gene variations had received more of 20 transfusions. We observed a significant increase in MDA levels in patients with MDS and IOL, suggesting an increased lipid peroxidation in these patients. The accumulation of MDA alters the organisation of membrane phospholipids, contributing to the process of cellular degeneration. Results show that excess iron intensifies the process of cell damage through oxidative stress

Analysis of HLA-A antigens and C282Y and H63D mutations of the HFE gene in Brazilian patients with hemochromatosis

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Bittencourt P.L.

2002-01-01

Full Text Available The hemochromatosis gene, HFE, is located on chromosome 6 in close proximity to the HLA-A locus. Most Caucasian patients with hereditary hemochromatosis (HH are homozygous for HLA-A3 and for the C282Y mutation of the HFE gene, while a minority are compound heterozygotes for C282Y and H63D. The prevalence of these mutations in non-Caucasian patients with HH is lower than expected. The objective of the present study was to evaluate the frequencies of HLA-A antigens and the C282Y and H63D mutations of the HFE gene in Brazilian patients with HH and to compare clinical and laboratory profiles of C282Y-positive and -negative patients with HH. The frequencies of HLA-A and C282Y and H63D mutations were determined by PCR-based methods in 15 male patients (median age 44 (20-72 years with HH. Eight patients (53% were homozygous and one (7% was heterozygous for the C282Y mutation. None had compound heterozygosity for C282Y and H63D mutations. All but three C282Y homozygotes were positive for HLA-A3 and three other patients without C282Y were shown to be either heterozygous (N = 2 or homozygous (N = 1 for HLA-A3. Patients homozygous for the C282Y mutation had higher ferritin levels and lower age at onset, but the difference was not significant. The presence of C282Y homozygosity in roughly half of the Brazilian patients with HH, together with the findings of HLA-A homozygosity in C282Y-negative subjects, suggest that other mutations in the HFE gene or in other genes involved in iron homeostasis might also be linked to HH in Brazil.

Progress of Design Improvements for APR1400 Computerized Procedure System from HFE V and V results and Design Experience

International Nuclear Information System (INIS)

Lee, Sungjin; Seong, Nokyu

2015-01-01

This study shows major already improved design features from the above three processes and a design proposal for to-be-improving items. APR1400 CPS has been verified and validated by the HFE process, internal design review and site acceptance tests. APR1400 Computerized Procedure System (CPS) has been applied to Shin-Kori Nuclear Power Plant (SKN) 3 and 4 units, Shin-Hanul Nuclear Power Plant (SHN) 1 and 2 units and Baraka Nuclear Power Plant (BNPP) 1, 2, 3 and 4 units. Since APR1400 CPS is a first-of-a-kind (FOAK) human machine interface (HMI) for executing a computerized procedure in the nuclear power plant's main control room in South Korea, it has been continuously improved through a) the human factor engineering (HFE) verification and validation (V and V), b) the internal design review and c) prototype tests. Human engineering discrepancies (HEDs) can be identified by the HFE V and V activity. Some HEDs of APR1400 CPS for SKN 3 and 4 and SHN 1 and 2 have been adopted as a role of design improvement in the CPS system while others were regarded as an operator training requirement or part of task contents. Various requests for improving the CPS have been collected from those results. A HMI system should be improved continuously for removing potential defects. Some of introduced design features in this paper has been adopted for APR1400 nuclear power plants. Some of them are under the review in the CPS design team of KHNP

Molecular epidemiology of HFE gene polymorphic variants (C282Y, H63D and S65C) in the population of Espírito Santo, Brazil.

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Alves, L N R; Santos, E V W; Stur, E; Silva Conforti, A M A; Louro, I D

2016-04-27

Hereditary hemochromatosis (HH) is an autosomal recessive disorder that leads to progressive iron accumulation and may cause cirrhosis, hepatocellular carcinoma, diabetes, and heart failure. Most cases of HH have been linked to mutations in genes associated with iron homeostasis. There have been three major variants in the high Fe (HFE) gene associated with the disease: C282Y, H63D and S65C. In this context, we aimed to evaluate the prevalence of the polymorphic variants (C282Y, H63D and S65C) of the HFE gene in the population of the Espírito Santo State (ES), Brazil by analyzing three different groups: general population (N = 120), Pomeranian descendants (N = 59), and patients with HH (N = 20). Using genomic DNA extracted from peripheral blood, polymorphic variant identification was performed by polymerase chain reaction-restriction fragment length polymorphism. Statistically significant differences were observed for genotype distribution of C282Y (P HFE gene allele frequencies for the general population, Pomeranian subpopulation, and patients with HH of ES, Brazil.

El rol del apoyo parental, las actitudes hacia la escuela y la autoestima en la violencia escolar en adolescentes

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Belén Martínez-Ferrer

2008-01-01

la autoestima escolar se encuentra negativamente asociada con la violencia. La autoestima familiar se asocia en sentido negativo con la violencia y la percepción de injusticia. Además, el apoyo del padre influye en la violencia de modo directo y a través de su relación con la autoestima familiar y escolar, mientras que el apoyo de la madre se asocia negativamente con la minusvaloración de los estudios y positivamente con la autoestima familiar y la escolar. Finalmente, se discuten los resultados y sus posibles implicaciones.

Encefalitis autoinmunitaria asociada a anticuerpos contra el receptor N-metil-D-aspartato: presentación de dos casos

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José Bustos; Yasmin Sánchez; Jhon Medina; Rommy Olivieri; Julián Mojica; Johan Ortiz

2017-01-01

La encefalitis asociada a anticuerpos contra receptores N-metil-D-aspartato es un síndrome neurológico que se presenta más comúnmente en mujeres jóvenes y frecuentemente se asocia al teratoma de ovario. Se caracteriza por un cuadro clínico agudo con síntomas generales inespecíficos que evoluciona hacia deterioro neurológico, psicosis y convulsiones; en su etapa más avanzada, se asocia con movimientos anormales y disautonomía. Se reportan dos casos en mujeres de 23 y 12 años. Dada su baja i...

HFE C282Y and H63D in adults with malignancies in a community medical oncology practice

International Nuclear Information System (INIS)

Barton, James C; Bertoli, Luigi F; Acton, Ronald T

2004-01-01

We sought to compare frequencies of HFE C282Y and H63D alleles and associated odds ratios (OR) in 100 consecutive unrelated white adults with malignancy to those in 318 controls. Data from patients with more than one malignancy were analyzed according to each primary malignancy. For the present study, OR ≥2.0 or ≤0.5 was defined to be increased or decreased, respectively. There were 110 primary malignancies (52 hematologic neoplasms, 58 carcinomas) in the 100 adult patients. Allele frequencies were similar in patients and controls (C282Y: 0.0850 vs. 0.0896, respectively (OR = 0.9); H63D: 0.1400 vs. 0.1447, respectively (OR = 0.9)). Two patients had hemochromatosis and C282Y homozygosity. With C282Y, increased OR occurred in non-Hodgkin lymphoma, myeloproliferative disorders, and adenocarcinoma of prostate (2.0, 2.8, and 3.4, respectively); OR was decreased in myelodysplasia (0.4). With H63D, increased OR occurred in myeloproliferative disorders and adenocarcinomas of breast and prostate (2.4, 2.0, and 2.0, respectively); OR was decreased in non-Hodgkin lymphoma and B-chronic lymphocytic leukemia (0.5 and 0.4, respectively). In 100 consecutive adults with malignancy evaluated in a community medical oncology practice, frequencies of HFE C282Y or H63D were similar to those in the general population. This suggests that C282Y or H63D is not associated with an overall increase in cancer risk. However, odds ratios computed in the present study suggest that increased (or decreased) risk for developing specific types of malignancy may be associated with the inheritance of HFE C282Y or H63D. Study of more patients with these specific types of malignancies is needed to determine if trends described herein would remain and yield significant differences

Ancestral association between HLA and HFE H63D and C282Y gene mutations from northwest Colombia.

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Rodriguez, Libia M; Giraldo, Mabel C; Velasquez, Laura I; Alvarez, Cristiam M; Garcia, Luis F; Jimenez-Del-Rio, Marlene; Velez-Pardo, Carlos

2015-03-01

A significant association between HFE gene mutations and the HLA-A*03-B*07 and HLA-A*29-B*44 haplotypes has been reported in the Spanish population. It has been proposed that these mutations are probably connected with Celtic and North African ancestry, respectively. We aimed to find the possible ancestral association between HLA alleles and haplotypes associated with the HFE gene (C282Y and H63D) mutations in 214 subjects from Antioquia, Colombia. These were 18 individuals with presumed hereditary hemochromatosis ("HH") and 196 controls. The HLA-B*07 allele was in linkage disequilibrium (LD) with C282Y, while HLA-A*23, A*29, HLA-B*44, and B*49 were in LD with H63D. Altogether, our results show that, although the H63D mutation is more common in the Antioquia population, it is not associated with any particular HLA haplotype, whereas the C282Y mutation is associated with HLA-A*03-B*07, this supporting a northern Spaniard ancestry.

Ancestral association between HLA and HFE H63D and C282Y gene mutations from northwest Colombia

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Libia M Rodriguez

2015-03-01

Full Text Available A significant association between HFE gene mutations and the HLA-A*03-B*07 and HLA-A*29-B*44 haplotypes has been reported in the Spanish population. It has been proposed that these mutations are probably connected with Celtic and North African ancestry, respectively. We aimed to find the possible ancestral association between HLA alleles and haplotypes associated with the HFE gene (C282Y and H63D mutations in 214 subjects from Antioquia, Colombia. These were 18 individuals with presumed hereditary hemochromatosis (“HH” and 196 controls. The HLA-B*07 allele was in linkage disequilibrium (LD with C282Y, while HLA-A*23, A*29, HLA-B*44, and B*49 were in LD with H63D. Altogether, our results show that, although the H63D mutation is more common in the Antioquia population, it is not associated with any particular HLA haplotype, whereas the C282Y mutation is associated with HLA-A*03-B*07, this supporting a northern Spaniard ancestry.

Lymphocyte gene expression signatures from patients and mouse models of hereditary hemochromatosis reveal a function of HFE as a negative regulator of CD8+ T-lymphocyte activation and differentiation in vivo.

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Costa, Mónica; Cruz, Eugénia; Oliveira, Susana; Benes, Vladimir; Ivacevic, Tomi; Silva, Maria João; Vieira, Inês; Dias, Francisco; Fonseca, Sónia; Gonçalves, Marta; Lima, Margarida; Leitão, Catarina; Muckenthaler, Martina U; Pinto, Jorge; Porto, Graça

2015-01-01

Abnormally low CD8+ T-lymphocyte numbers is characteristic of some patients with hereditary hemochromatosis (HH), a MHC-linked disorder of iron overload. Both environmental and genetic components are known to influence CD8+ T-lymphocyte homeostasis but the role of the HH associated protein HFE is still insufficiently understood. Genome-wide expression profiling was performed in peripheral blood CD8+ T lymphocytes from HH patients selected according to CD8+ T-lymphocyte numbers and from Hfe-/- mice maintained either under normal or high iron diet conditions. In addition, T-lymphocyte apoptosis and cell cycle progression were analyzed by flow cytometry in HH patients. HH patients with low CD8+ T-lymphocyte numbers show a differential expression of genes related to lymphocyte differentiation and maturation namely CCR7, LEF1, ACTN1, NAA50, P2RY8 and FOSL2, whose expression correlates with the relative proportions of naïve, central and effector memory subsets. In addition, expression levels of LEF1 and P2RY8 in memory cells as well as the proportions of CD8+ T cells in G2/M cell cycle phase are significantly different in HH patients compared to controls. Hfe-/- mice do not show alterations in CD8+ T-lymphocyte numbers but differential gene response patterns. We found an increased expression of S100a8 and S100a9 that is most pronounced in high iron diet conditions. Similarly, CD8+ T lymphocytes from HH patients display higher S100a9 expression both at the mRNA and protein level. Altogether, our results support a role for HFE as a negative regulator of CD8+ T-lymphocyte activation. While the activation markers S100a8 and S100a9 are strongly increased in CD8+ T cells from both, Hfe-/- mice and HH patients, a differential profile of genes related to differentiation/maturation of CD8+ T memory cells is evident in HH patients only. This supports the notion that HFE contributes, at least in part, to the generation of low peripheral blood CD8+ T lymphocytes in HH.

Iron overload and genotype 3 are associated with liver steatosis in chronic hepatitis C Sobrecarga de hierro y genotipo 3 se asocian a la presencia de esteatosis en la hepatitis C

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L. I. Fernández Salazar

2004-12-01

Full Text Available Objective: to determine epidemiological, biochemical, virological, and histological factors associated with liver steatosis in chronic hepatitis C. Subjects: the medical histories of 53 patients biopsied for chronic hepatitis C diagnosis between June 2000 and December 2002 were retrospectively studied. Epidemiological, biochemical, and virological data were collected. Patients with hepatitis B virus or human immunodeficiency virus coinfection were excluded. Liver biopsy specimens were reviewed and scored by one pathologist. Weight and height were measured at liver biopsy time. The statistic association between qualitative and quantitative variables and the presence of liver steatosis was studied. Results: steatosis was identified in 52% of biopsies. There was no statistic association with age, sex, method of transmission, duration of infection, alcohol consumption, other diseases, body mass index, glucose, triglycerides, cholesterol, AST, ALT, GGT, alkaline phosphatase, bilirubin, or viral load. Liver steatosis was associated with serum iron, transferrin saturation, and ferritin. Genotype 3 was also associated with steatosis. Piecemeal necrosis, hepatocellular injury, Kupffer cell hyperplasia, liver iron, and portal fibrosis were also associated with steatosis. A multivariate analysis showed that genotype 3, Kupffer cell hyperplasia, and liver iron were associated with the presence of steatosis. Conclusions: liver steatosis in chronic hepatitis C associates with genotype 3, Kupffer cell hyperplasia, and iron overload. Hepatic steatosis also associates with greater inflammation and fibrosis, and must be considered to contribute to disease progression.Objetivo: determinar los factores epidemiológicos, analíticos, virológicos e histológicos a los que se asocia la esteatosis en la hepatitis C. Pacientes: se revisaron de forma retrospectiva 53 historias clínicas de pacientes biopsiados consecutivamente desde junio de 2000 a dicembre de 2002. Se

Frequency of Hereditary Hemochromatosis (HFE) Gene Mutations in Egyptian Beta Thalassemia Patients and its Relation to Iron Overload.

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Enein, Azza Aboul; El Dessouky, Nermine A; Mohamed, Khalda S; Botros, Shahira K A; Abd El Gawad, Mona F; Hamdy, Mona; Dyaa, Nehal

2016-06-15

This study aimed to detect the most common HFE gene mutations (C282Y, H63D, and S56C) in Egyptian beta thalassemia major patients and its relation to their iron status. The study included 50 beta thalassemia major patients and 30 age and sex matched healthy persons as a control group. Serum ferritin, serum iron and TIBC level were measured. Detection of the three HFE gene mutations (C282Y, H63D and S65C) was done by PCR-RFLP analysis. Confirmation of positive cases for the mutations was done by sequencing. Neither homozygote nor carrier status for the C282Y or S65C alleles was found. The H63D heterozygous state was detected in 5/50 (10%) thalassemic patients and in 1/30 (3.3%) controls with no statistically significant difference between patients and control groups (p = 0.22). Significantly higher levels of the serum ferritin and serum iron in patients with this mutation (p = 001). Our results suggest that there is an association between H63D mutation and the severity of iron overload in thalassemic patients.

Correlation between HFE gene polymorphisms and increased risk of coronary artery disease among patients with type 2 diabetes in Iran.

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Saremi, Leila; Saremi, Marzieh; Lotfipanah, Shirin; İmani, Saber; Fu, Junjiang; Zhang, Tianyu

2016-04-19

Diabetes mellitus is a risk factor for cardiovascular diseases (CVDs), which are among the major causes of deaths in type 2 diabetes (T2D). The purpose of the present study was to determine the association of C282Y and H63D mutations in the HFE gene with increased risk of coronary artery disease (CAD) in T2D patients. Two hundred and ninety individuals were divided into two groups: a case group and a control group. Genomic DNA of peripheral venous blood cells was extracted and the HFE gene mutations were analyzed using the PCR-RFLP technique. Data analysis revealed a significant difference between the allele frequencies of H63D and C282Y mutations between the case group and the controls (P 0.05). Using a logistic regression model, BMI, FBS, HDL, and total cholesterol levels were significantly different with independent predictors of CVD (P < 0.05). Our results revealed a significant correlation between C282Y and H63D mutations and the development of CAD in T2D patients.

Condición física, adiposidad y autoconcepto en adolescentes. Estudio piloto

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Alejandro Garc\\u00EDa-S\\u00E1nchez; Rafael Burgue\\u00F1o-Menjibar; David L\\u00F3pez-Blanco; Francisco B. Ortega

2013-01-01

Un alto índice de masa corporal y una baja capacidad aeróbica se asocia con un peor autoconcepto. Se ha observado también que personas obesas pero con buena forma física están físicamente sanos, fenómeno conocido como “fat but fit”. El presente estudio pretende: 1) determinar la relación entre cantidad de grasa corporal y principales componentes de la condición física con el autoconcepto en adolescentes; 2) testar si el fenómeno fat but fit se asocia con un mejor autoconcepto. Un total de 69 ...

Experiencia en la Argentina del Programa de uso compasivo con nintedanib en el tratamiento de la Fibrosis Pulmonar Idiopática

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Tabaj, Gabriela C; Sívori, Martín; Cornejo, Laura; Plotquin, Martín

2017-01-01

Introducción: La Fibrosis Pulmonar Idiopática (FPI) es una enfermedad pulmonar difusa (EPD) de etiología desconocida, crónica y progresiva. Ocurre en adultos mayores, se encuentra limitada a los pulmones y se asocia con la patente anatomopatológica y/o tomográfica de neumonía intersticial usual (NIU). El curso de la enfermedad es progresivo y se asocia con una supervivencia media a 5 años del 20%. Objetivos: Conocer las características clínicas y de función pulmonar del grupo de pacientes con...

Association of HFE gene C282Y and H63D mutations with liver cirrhosis in the Lithuanian population.

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Juzėnas, Simonas; Kupčinskas, Juozas; Valantienė, Irena; Šumskienė, Jolanta; Petrenkienė, Vitalija; Kondrackienė, Jūrate; Kučinskas, Laimutis; Kiudelis, Gediminas; Skiecevičienė, Jurgita; Kupčinskas, Limas

2016-01-01

Liver cirrhosis is the end-stage disease of chronic liver injury. Due to differences in the natural course of chronic liver diseases, identification of genetic factors that influence individual outcomes is warranted. HFE-linked hereditary hemochromatosis (HH) predisposes disease progression to cirrhosis; however, the role of heterozygous C282Y or H63D mutations in the development of cirrhosis in the presence of other etiological factors is still debated. The aim of this study was to determine the association between heterozygous C282Y and H63D mutations and non-HH liver cirrhosis in Lithuanian population. The patient cohort consisted of 209 individuals. Diagnosis of cirrhosis was confirmed by clinical, laboratory parameters, liver biopsy, and radiological imaging. Control samples were obtained from 1005 randomly selected unrelated healthy individuals. HFE gene mutations were determined using the PCR-RFLP method. The most common causes of cirrhosis were hepatitis C (33.9%), hepatitis B (13.6%), and alcohol (25.8%). C282Y allele was associated with the presence of cirrhosis (OR=2.07; P=0.005); this was also observed under recessive model for C282Y (OR=2.06, P=0.008). The prevalence of C282Y allele was higher in cirrhotic men than in controls (7.0% vs. 2.8%, P=0.002). The carriage of H63D risk allele (OR=1.54; P=0.02), heterozygous C282Y/wt and homozygous H63D/H63D genotypes were associated with liver cirrhosis in males (OR=2.48, P=0.008, and OR=4.13, P=0.005, respectively). Heterozygous C282Y mutation of the HFE gene was associated with liver cirrhosis in the Lithuanian population. In gender-related analysis, heterozygous C282Y and homozygous H63D mutations were linked to liver cirrhosis in men, not in women. Copyright © 2016 The Lithuanian University of Health Sciences. Production and hosting by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

Four variants in transferrin and HFE genes as potential markers of iron deficiency anaemia risk: an association study in menstruating women

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Arroyo-Pardo Eduardo

2011-10-01

Full Text Available Abstract Background Iron deficiency anaemia is a worldwide health problem in which environmental, physiologic and genetic factors play important roles. The associations between iron status biomarkers and single nucleotide polymorphisms (SNPs known to be related to iron metabolism were studied in menstruating women. Methods A group of 270 Caucasian menstruating women, a population group at risk of iron deficiency anaemia, participated in the study. Haematological and biochemical parameters were analysed and 10 selected SNPs were genotyped by minisequencing assay. The associations between genetic and biochemical data were analysed by Bayesian Model Averaging (BMA test and decision trees. Dietary intake of a representative subgroup of these volunteers (n = 141 was assessed, and the relationship between nutrients and iron biomarkers was also determined by linear regression. Results Four variants, two in the transferrin gene (rs3811647, rs1799852 and two in the HFE gene (C282Y, H63D, explain 35% of the genetic variation or heritability of serum transferrin in menstruating women. The minor allele of rs3811647 was associated with higher serum transferrin levels and lower transferrin saturation, while the minor alleles of rs1799852 and the C282Y and H63D mutations of HFE were associated with lower serum transferrin levels. No association between nutrient intake and iron biomarkers was found. Conclusions In contrast to dietary intake, these four SNPs are strongly associated with serum transferrin. Carriers of the minor allele of rs3811647 present a reduction in iron transport to tissues, which might indicate higher iron deficiency anaemia risk, although the simultaneous presence of the minor allele of rs1799852 and HFE mutations appear to have compensatory effects. Therefore, it is suggested that these genetic variants might potentially be used as markers of iron deficiency anaemia risk.

Compresión de señales electroencefalográficas epilépticas y normales

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Fernando Cruz Roldán

2012-02-01

Full Text Available Normal 0 21 false false false MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Tabla normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman"; mso-ansi-language:#0400; mso-fareast-language:#0400; mso-bidi-language:#0400;} Las señales electroencefalográficas son empleadas en el estudio de varias enfermedades, pero generan volúmenes de datos que dificultan su procesamiento. La compresión de estas señales permite disminuir el volumen de datos adquiridos, facilitando su manipulación.   La epilepsia es una de las más comunes de esas enfermedades y las señales que registran este tipo de anomalía difieren algo de las señales electroencefalográficas comunes. En este trabajo se analiza el comportamiento de la compresión de señales que contienen episodios epilépticos, comparado con otras que no lo contienen. Se establecen un grupo de parámetros de calidad y de compresión para establecer la comparación. Como resultado se obtiene una mejor calidad y una mayor compresión cuando la señal contiene episodios epilépticos. Este resultado se asocia a la sincronización que ocurre en estos casos y la correspondiente contracción de las bandas de frecuencia con mayor contenido de información relevante.

The association between the C282Y and H63D polymorphisms of HFE gene and the risk of Parkinson's disease: A meta-analysis.

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Xia, Jianjian; Xu, Huamin; Jiang, Hong; Xie, Junxia

2015-05-19

Impaired brain iron homeostasis has been considered as an important mechanism in Parkinson's diseases (PD). There are indications that C282Y and H63D polymorphisms of HFE genes involved in iron metabolism might contribute to the pathogenesis of PD in some cases. However, the investigation of the relationship between PD and the two polymorphisms had produced contradictory results. We performed a meta-analysis to assess the C282Y and H63D polymorphisms of HFE in PD susceptibility. PubMed, EMBASE and Web of Science were systematically searched to identify relevant researches. The strict selection criteria and exclusion standard were applied. Odds ratios (ORs) with 95% confidence intervals (CIs) were used to assess the strength of associations. A fixed-effect or random-effect model was selected, depending on the results of the heterogeneity test. Fifteen studies were included in the meta-analysis (eight studies with 1631 cases and 4548 controls for C282Y; seven studies with 1192 cases and 4065 controls for H63D). For the C282Y polymorphism, significant associations were observed in the Recessive model (YY vs CY+CC: OR=0.22, 95% CI=0.09-0.57, P=0.002). This indicated that the C282Y polymorphism in HFE might be a potential protective factor for PD. However, no significant associations were found for any genetic model for the H63D polymorphism, suggesting that the H63D polymorphism might not be associated with PD. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Porfiria cutánea tarda: asociación con mutaciones HFE, hepatitis virales, alcohol y otros factores de riesgo en Guipúzcoa, País Vasco Porphyria cutanea tarda: An analysis of HFE gene mutations, hepatitis viruses, alcohol intake, and other risk factors in 54 patients from Guipúzcoa, Basque Country, Spain

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A. Castiella

2008-12-01

Full Text Available Objetivo: estudiar la frecuencia de las mutaciones en el gen HFE (C282Y, H63D, S65C en un grupo de 54 pacientes con porfiria cutánea tarda (PCT y en un grupo de controles sanos (donantes de sangre en Guipúzcoa. También analizar su relación con los virus de la hepatitis B y C (VHB, VHC, alcohol y otros factores de riesgo reconocidos. Métodos: el análisis de las mutaciones se hizo mediante PCR. Se compararon las frecuencias alélicas y genotípicas. Se determinaron la probabilidad y el test de Chi cuadrado. Resultados: no encontramos asociación entre C282Y y PCT (5,76 vs. 5% controles. Se observó una alta frecuencia alélica en la mutación H63D en PCT (34,25%, pero sin ser estadísticamente significativa (controles 29,31%, debido a la alta prevalencia de esta mutación en la población vasca. La mutación S65C fue menor en PCT que en controles. Encontramos una idéntica presencia de H63D en heterocigosis en ambos grupos (38,8 vs. 38,8%. La asociación con el VHC se objetivó en el 35,18% de los pacientes y la infección por VHB en el 7,4%. Un 55,55% de los pacientes tenía un hábito alcohólico de más de 60 g etanol día. Todos eran negativos para el virus de la inmunodeficiencia humana (VIH y 1 de las 5 mujeres con PCT tomaba estrógenos. Conclusión: las mutaciones C282Y y H63D no tienen un papel relevante en los pacientes con PCT en Guipúzcoa. Los factores externos (consumo importante de alcohol y VHC parecen jugar un papel fundamental en el desarrollo de la PCT en nuestra población.Aim: to study the frequency of HFE gene mutations (C282Y, H63D, S65C in a group of 54 sporadic PCT patients and in a group of healthy controls (blood donors from Guipúzcoa, Spain. We studied the association of PCT with HCV, HBV, alcohol abuse, and other established risk factors. Methods: the analysis of mutations was made by PCR. Allelic and genotypic frequencies were compared. Probability was determined and a Chi-squared test was performed. Results

ERAD defects and the HFE-H63D variant are associated with increased risk of liver damages in Alpha 1-Antitrypsin Deficiency

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Di Martino, Julie; Ruiz, Mathias; Garin, Roman; Restier, Lioara; Belmalih, Abdelouahed; Marchal, Christelle; Cullin, Christophe; Arveiler, Benoit; Fergelot, Patricia; Gitler, Aaron D.; Lachaux, Alain; Couthouis, Julien

2017-01-01

Background The most common and severe disease causing allele of Alpha 1-Antitrypsin Deficiency (1ATD) is Z-1AT. This protein aggregates in the endoplasmic reticulum, which is the main cause of liver disease in childhood. Based on recent evidences and on the frequency of liver disease occurrence in Z-1AT patients, it seems that liver disease progression is linked to still unknown genetic factors. Methods We used an innovative approach combining yeast genetic screens with next generation exome sequencing to identify and functionally characterize the genes involved in 1ATD associated liver disease. Results Using yeast genetic screens, we identified HRD1, an Endoplasmic Reticulum Associated Degradation (ERAD) associated protein, as an inducer of Z-mediated toxicity. Whole exome sequencing of 1ATD patients resulted in the identification of two variants associated with liver damages in Z-1AT homozygous cases: HFE H63D and HERPUD1 R50H. Functional characterization in Z-1AT model cell lines demonstrated that impairment of the ERAD machinery combined with the HFE H63D variant expression decreased both cell proliferation and cell viability, while Unfolded Protein Response (UPR)-mediated cell death was hyperstimulated. Conclusion This powerful experimental pipeline allowed us to identify and functionally validate two genes involved in Z-1AT-mediated severe liver toxicity. This pilot study moves forward our understanding on genetic modifiers involved in 1ATD and highlights the UPR pathway as a target for the treatment of liver diseases associated with 1ATD. Finally, these findings support a larger scale screening for HERPUD1 R50H and HFE H63D variants in the sub-group of 1ATD patients developing significant chronic hepatic injuries (hepatomegaly, chronic cholestasis, elevated liver enzymes) and at risk developing liver cirrhosis. PMID:28617828

Ausência de descenso noturno se associa a acidente vascular cerebral e infarto do miocárdio La ausencia de descenso nocturno de la presión arterial se asocia a accidente cerebrovascular e infarto de miocardio Absence of nocturnal dipping is associated with stroke and myocardium infarction

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Renan Oliveira Vaz-de-Melo

2010-01-01

Full Text Available FUNDAMENTO: A pressão arterial (PA varia de acordo com o ciclo circadiano, apresentando quedas fisiológicas durante o sono (descenso noturno - DN. A ausência dessa queda se associa a maior incidência de lesões em órgãos-alvo. OBJETIVO: Analisar a prevalência de DN em indivíduos hipertensos, correlacionar DN aos níveis pressóricos, variáveis clínicas, fatores sociodemográficos e bioquímicos e associá-lo a eventos cardiovasculares (acidente vascular cerebral - AVC e infarto agudo do miocárdio - IAM. MÉTODOS: Foram avaliados 163 hipertensos, submetidos a monitorização ambulatorial da pressão arterial. DN foi definido como queda >10% da PA sistólica do período da vigília para o de sono. RESULTADOS: Os pacientes foram divididos em grupos dipper (D e não dipper (ND. Não houve diferença significante entre os grupos quanto a idade, sexo, raça, tempo de hipertensão, glicemia, LDL-colesterol, colesterol total, triglicérides, escolaridade, tabagismo, história de diabetes. Grupo dipper apresentou PA superior a ND durante a vigília e inferior durante o sono. Grupo ND cursou com maior índice de massa corpórea (IMC (p=0,0377, menor HDL-colesterol (p=0,0189 e maior pressão de pulso durante o sono (p=0,0025. História de AVC ou IAM foram mais frequentes em ND. À regressão logística, apenas a ausência de descenso noturno associou-se independentemente a AVC ou IAM. CONCLUSÃO: A ausência de DN associou-se de maneira independente às lesões em órgãos-alvo analisadas, o que demonstra a sua importância e reforça a necessidade de tratamento mais agressivo com objetivo de se atingir as metas pressóricas e, consequentemente, evitar o desenvolvimento de novos eventos cardiocerebrovasculares.FUNDAMENTO: La presión arterial (PA varía de acuerdo al ciclo circadiano, presentando descensos fisiológicos durante el sueño (descenso nocturno - DN. La ausencia de ese descenso se asocia a mayor incidencia de lesiones en �

HFE gene mutation and iron overload in Egyptian pediatric acute lymphoblastic leukemia survivors: a single-center study.

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El-Rashedi, Farida H; El-Hawy, Mahmoud A; El-Hefnawy, Sally M; Mohammed, Mona M

2017-08-01

Hereditary hemochromatosis gene (HFE) mutations have a role in iron overload in pediatric acute lymphoblastic leukemia (ALL) survivors. We aimed to evaluate the genotype frequency and allelic distribution of the two HFE gene mutations (C282Y and H63D) in a sample of Egyptian pediatric ALL survivors and to detect the impact of these two mutations on their iron profile. This study was performed on 35 ALL survivors during their follow-up visits to the Hematology and Oncology Unit, Pediatric Department, Menoufia University Hospitals. Thirty-five healthy children of matched age and sex were chosen as controls. After completing treatment course, ALL survivors were screened for the prevalence of these two mutations by polymerase chain reaction-restriction fragment length polymorphism. Serum ferritin levels were measured by an enzyme-linked immunosorbent assay technique (ELISA). C282Y mutation cannot be detected in any of the 35 survivors or the 35 controls. The H63D heterozygous state (CG) was detected in 28.6% of the survivors group and in 20% of controls, while the H63D homozygous (GG) state was detected in 17.1% of survivors. No compound heterozygosity (C282Y/H63D) was detected at both groups with high G allele frequency (31.4%) in survivors more than controls (10%). There were significant higher levels of iron parameters in homozygote survivors than heterozygotes and the controls. H63D mutation aggravates the iron overload status in pediatric ALL survivors.

Mutations in HAMP and HJV genes and their impact on expression of clinical hemochromatosis in a cohort of 100 Spanish patients homozygous for the C282Y mutation of HFE gene.

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Altès, Albert; Bach, Vanessa; Ruiz, Angels; Esteve, Anna; Felez, Jordi; Remacha, Angel F; Sardà, M Pilar; Baiget, Montserrat

2009-10-01

Most hereditary hemochromatosis (HH) patients are homozygous for the C282Y mutation of the HFE gene. Nevertheless, penetrance of the disease is very variable. In some patients, penetrance can be mediated by concomitant mutations in other iron master genes. We evaluated the clinical impact of hepcidin (HAMP) and hemojuvelin mutations in a cohort of 100 Spanish patients homozygous for the C282Y mutation of the HFE gene. HAMP and hemojuvelin mutations were evaluated in all patients by bidirectional direct cycle sequencing. Phenotype-genotype interactions were evaluated. A heterozygous mutation of the HAMP gene (G71D) was found in only one out of 100 cases. Following, we performed a study of several members of that family, and we observed several members had a digenic inheritance of the C282Y mutation of the HFE gene and the G71D mutation of the HAMP gene. This mutation in the HAMP gene did not modify the phenotype of the individuals who were homozygous for the C282Y mutation. One other patient presented a new polymorphism in the hemojuvelin gene, without consequences in iron load or clinical course of the disease. In conclusion, HAMP and hemojuvelin mutations are rare among Spanish HH patients, and their impact in this population is not significant.

RETARDO DE CRECIMIENTO INTRAUTERINO: CONSECUENCIAS A LARGO PLAZO

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Int. Med. Tomás Rybertt

2016-07-01

Full Text Available El retardo del crecimiento intrauterino (RCIU se asocia a factores de riesgo maternos y a causas placentarias y dependientes del feto. La aparición de esta patología es de relevancia dado que se asocia en el corto plazo a morbilidad-mortalidad neonatal, así como en la incidencia en patologías crónicas de la vida adulta. Este artículo revisa principalmente las consecuencias a largo plazo de RCIU en cuanto al crecimiento post-natal, neurodesarrollo y describe cómo a través de la hipótesis de Barker se relaciona esta condición con enfermedad coronaria, diabetes mellitus e hipertensión arterial.

Variations in CCR5, but not HFE, ELMO1, or SLC12A3, are associated with susceptibility to kidney disease in north Indian individuals with type 2 diabetes.

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Yadav, Ashok K; Kumar, Vinod; Dutta, Pinaki; Bhansali, Anil; Jha, Vivekanand

2014-11-01

Diabetic nephropathy (DN), the leading cause of end-stage renal disease worldwide, may have a genetic component. In the present study, we investigated variations in a set of genes with susceptibility to DN in a north Indian population. Four genes (HFE, ELMO1, SLC12A3, and CCR5) were selected on the basis of reported association with type 2 diabetes and nephropathy. In all, 417 diabetic subjects (215 without kidney disease [DM] and 202 with DN) and 197 healthy controls (HC) were evaluated for variations in HFE (845 G>A and 187G>C), SLC12A3 (g.34372G>A), CCR5 (59029A>G), and ELMO1 (+9170 G>A). Polymorphism analysis was performed by polymerase chain reaction-restriction fragment length polymorphism and Taqman allele discrimination assays. Significant differences were found in genotype and allelic frequency in SLC12A3 (g.34372G>A) between diabetic subjects and HC (P A (AA+GA) genotype between diabetic subjects with and without nephropathy. However, the CCR5 59029AA genotype and A allele were significantly more frequent in diabetics compared with the HC (P = 0.01 and 0.03, respectively) and subjects with DN versus DM (P = 0.002 and 0.01, respectively). For ELMO1 (+9170 G>A), the GG genotype frequency was higher in the diabetic versus HC group. There were no differences in the frequency of HFE-845 G>A and HFE-187G>C among the groups. This study shows that the CCR5 AA genotype is over-represented in subjects with kidney disease due to type 2 diabetes. The CCR5 59029G>A and ELMO1 (+9170 G>A) loci are more frequent, and the SLC12A3 34372 AA genotype is associated with a reduced risk of diabetes. © 2014 Ruijin Hospital, Shanghai Jiaotong University School of Medicine and Wiley Publishing Asia Pty Ltd.

Survey of HFE Gene C282Y Mutation in Turkish Beta-Thalassemia Patients and Healthy Population: A Preliminary Study

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Selma Ünal

2014-09-01

Full Text Available OBJECTIVE: This study was planned in order to determine the effect of C282Y mutation in development of secondary hemochromatosis in beta-thalassemia patients and to determine the prevalence and allele frequency of this mutation in a healthy control group. METHODS: Eighty-seven children and young adults (46 males and 41 females; mean age: 15.6±6.1 years, range: 3-30 years with beta-thalassemia major (BTM and 13 beta-thalassemia intermedia (BTI patients (6 males and 7 females; mean age: 19.6±3.5 years, range: 13-26 years were included in the study. The control group comprised 100 healthy blood donors. RESULTS: Neither heterozygous nor homozygous HFE gene C282Y mutation was detected in patients with BTM or BTI, or in control group. CONCLUSION: The C282Y mutation, which is supposed to be responsible for the majority of hereditary hemochromatosis, was not found to have a role in the development of hemochromatosis in beta-thalassemia patients and was not detected in a healthy Turkish population. However, research on larger cohorts of individuals is required in order to determine the exact prevalence of the HFE gene mutation in Turkish populations from diverse ethnic origins and whether it would have an impact on iron loading in thalassemic populations.

Loss of Hfe Leads to Progression of Tumor Phenotype in Primary Retinal Pigment Epithelial Cells

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Gnana-Prakasam, Jaya P.; Veeranan-Karmegam, Rajalakshmi; Coothankandaswamy, Veena; Reddy, Sushma K.; Martin, Pamela M.; Thangaraju, Muthusamy; Smith, Sylvia B.; Ganapathy, Vadivel

2013-01-01

Purpose. Hemochromatosis is a disorder of iron overload arising mostly from mutations in HFE. HFE is expressed in retinal pigment epithelium (RPE), and Hfe−/− mice develop age-related iron accumulation and retinal degeneration associated with RPE hyperproliferation. Here, the mechanism underlying the hyperproliferative phenotype in RPE was investigated. Methods. Cellular senescence was monitored by β-galactosidase activity. Gene expression was monitored by real-time PCR. Survivin was analyzed by Western blot and immunofluorescence. Migration and invasion were monitored using appropriate kits. Glucose transporters (GLUTs) were monitored by 3-O-methyl-D-glucose uptake. Histone deacetylases (HDACs) were studied by monitoring catalytic activity and acetylation status of histones H3/H4. Results. Hfe−/− RPE cells exhibited slower senescence rate and higher survivin expression than wild type cells. Hfe−/− cells migrated faster and showed greater glucose uptake and increased expression of GLUTs. The expression of HDACs and DNA methyltransferase (DNMTs) also was increased. Similarly, RPE cells from hemojuvelin (Hjv)-knockout mice, another model of hemochromatosis, also had increased expression of GLUTs, HDACs, and DNMTs. The expression of Slc5a8 was decreased in Hfe−/− RPE cells, but treatment with a DNA methylation inhibitor restored the transporter expression, indicating involvement of DNA methylation in the silencing of Slc5a8 in Hfe−/− cells. Conclusions. RPE cells from iron-overloaded mice exhibit several features of tumor cells: decreased senescence, enhanced migration, increased glucose uptake, and elevated levels of HDACs and DNMTs. These features are seen in Hfe−/− RPE cells as well as in Hjv−/− RPE cells, providing a molecular basis for the hyperproliferative phenotype of Hfe−/− and Hjv−/− RPE cells. PMID:23169885

Review of advanced control rooms: Methodological considerations for the use of HFE guidelines

International Nuclear Information System (INIS)

O'Hara, J.M.

1994-01-01

Control rooms for advanced nuclear power plants use advanced human-system interface (HSI) technologies that may have significant implications for plant safety in that they will affect the operator's overall role in the system and the ways in which operators interact with the system. The US Nuclear Regulatory Commission (NRC) reviews HSIs to ensure that they are designed to accepted human factors engineering (HFE) principles. The principal review guidance, however, is more than ten-years old (US NRC, 1981). Accordingly, an Advanced HSI Design Review Guideline (DRG) was developed to provide criteria for these reviews. The DRG contains seven major sections: Information Display, User-System Interaction, Process Control and Input Devices, Alarms, Analysis and Decision Aids, Inter-Personnel Communication, and Workplace Design (see O'Hara ampersand Brown, 1993). The purpose of this paper is to describe the methodology for DRG use

[ALLELES C282Y AND H63D HFE GENE, INSULIN RESISTANCE AND SUSCEPTIBILITY TO DISTURBANCE OF PORPHYRIN METABOLISM IN NON-ALCOHOLIC FATTY LIVER DISEASE].

Science.gov (United States)

Krivosheev, A B; Maximov, V N; Voevoda, M I; Kuimov, A D; Kondratova, M A; Tuguleva, T A; Koval, O N; Bezrukova, A A; Bogorianova, P A; Rybina, O V

2015-01-01

The aim of the present work was to study the frequency of genotypes and alleles of C282Y and H63D HFE gene that may be associated with impaired porphyrin metabolism, as well as possible reasons for the formation of dysmetabolism porphyrins with NAFLD. The study involved 65 patients (52 men and 13 women) aged 21 to 69 years (mean age 48.5±1.5 years). Excretion uroporphyrin, coproporphyrin, 6-aminolevulinic acid of porphobilinogen in urine was determined by chromatography and spectrophotometry calculated total excretion of porphyrins. Allele frequencies C282Y and H63D were determined during the molecular genetic analysis of DNA using the polymerase chain reaction followed by analysis of length polymorphism restraktsionnyh fragments. Condition of carbohydrate metabolism was evaluated by the level of fasting blood glucose and standard glucose tolerance test. Diagnosis of insulin resistance was performed according to the criteria proposed by the European Group for the Study of insulin resistance (EGIR). Skill test for the C282Y mutation carriage and H63D in the HFE gene in 65 patients with non-alcoholic fatty liver disease. Disturbances in the metabolism of porphyrins were recorded in 43 (66.2%) patients. H63D and C282Y mutations were found in 18 (27.7%) patients, of whom 13 (72.2%) people with different options dismetabolism porphyrins and signs of insulin resistance. In 47 (72.3%) patients without mutations studied porphyrin metabolism disorders were detected in 30 (63.8 %), of which insulin resistance is registered only in 16 (34.0 %). Detection of mutations C282Y and H63D in the HFE gene in combination with disorders of porphyrin metabolism on the background of insulin resistance is likely to allow such patients considered as candidates for inclusion in the higher risk of formation of diabetes.

Fenotipos de válvula aórtica bicúspide y dilatación de aorta ascendente : estudio mediante cardiorresonancia.

OpenAIRE

Domingo Valero, Diana

2012-01-01

El objetivo del estudio ha sido caracterizar mediante cardiorresonancia los fenotipos de válvula aórtica bicúspide (VAB) y su asociación con patrones de dilatación de aorta ascendente (AA). En este estudio la VAB fenotipo 1 (fusión velo coronario derecho -izquierdo) es la más prevalente y se asocia a coartación aórtica, insuficiencia aórtica moderada-severa y dilatación de raiz aórtica. El fenotipo 2 de VAB (fusión velo coronario derecho- no coronario) se asocia a dilatación de porción tubula...

Cambios de la función renal tras la suspensión de análogos de vitamina D en la enfermedad renal crónica avanzada

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Francisco Caravaca

2018-03-01

Conclusiones: La suspensión de AVD en pacientes con ERC se asocia con una mejoría significativa de la función renal estimada. La magnitud de estos cambios se relaciona principalmente con la calcemia basal.

Population-based analysis of the frequency of HFE gene polymorphisms: Correlation with the susceptibility to develop hereditary hemochromatosis.

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Katsarou, Martha-Spyridoula; Latsi, Rosana; Papasavva, Maria; Demertzis, Nikolaos; Kalogridis, Thodoris; Tsatsakis, Aristides M; Spandidos, Demetrios A; Drakoulis, Nikolaos

2016-07-01

Hereditary hemochromatosis (HH) is an autosomal recessive genetic disease, characterized by increased dietary iron absorption. Due to the absence of an effective excretory mechanism, the excess iron in the body may accumulate resulting in toxic effects. The HFE gene also affects the activity of hepcidin, a hormone which acts as a negative regulator of iron metabolism. In this study, we performed a population-based analysis of the distribution of three hemochromatosis-related polymorphisms in the HFE gene (rs1800562, rs1799945 and rs1800730). DNA from 1,446 non‑related individuals of Greek ethnicity was collected and analyzed, either from whole blood or buccal swabs. The frequency distribution of these HFE gene polymorphisms was then determined. The results revealed that in our Greek population cohort (gr) the frequencies of each polymorphism were as follows: rs1800562: GG (wild‑type)=97.0%, GA=1.5%, AA=1.5%; rs1799945: CC (wild‑type)=74.4%, CG=23.4%, GG=2.2%; rs1800730: AA (wild‑type)=98.1%, AT=1.5% and TT=0.4%. No association between the HFE polymorphisms rs1800562, rs1799945 and rs1800730 and gender could be established. As regards the rs1800562 polymorphism, the A allele (mutant) was ~1.8‑fold more frequent in the European population (eur) than in the Greek population [(gr)=2,3%<(eur)=4%]. As for the rs1799945 polymorphism, the G allele (mutant) was 1.2‑fold more frequent in the European population than in the Greek population [(gr)=13,9%<(eur)=17%]. As regards the rs1800730 polymorphism, the T allele (mutant) was ~1.7‑fold more frequent in the European population than in the Greek population [(gr)=1.2%<(eur)=2%]. However, these pathogenic mutations were found more frequently in the Greek population compared to the global population (gl) [rs1800562: (gl)=1%<(gr)=2,3%; rs1799945: (gl)=7%<(gr)=13,9%; rs1800730: (gl)=<1%<(gr)=1.2%]. This suggests that the Greek population may differ genetically from the northern European population

Clásicos colombianos : la peregrinación de Alpha

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Carlos Arturo Caparroso

1959-09-01

Full Text Available Cuando se le recuerda en función literaria, el nombre de Manuel Ancízar se asocia inmediatamente al título de Peregrinación de Alpha, relación de viajes aparecida en Bogotá en 1853.

Gender and plasma iron biomarkers, but not HFE gene mutations, increase the risk of colorectal cancer and polyps.

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Castiella, Agustin; Múgica, Fernando; Zapata, Eva; Zubiaurre, Leire; Iribarren, Arantxa; de Juan, M Dolores; Alzate, Luis; Gil, Ines; Urdapilleta, Gregorio; Otazua, Pedro; Emparanza, José Ignacio

2015-09-01

A cohort study of patients included in the Basque Country colorectal cancer (CRC) screening programme was carried out to assess the risk of adenomatous polyps and CRC (P-CRC) associated with HFE gene mutations, with gender and with iron biomarkers (serum ferritin (SF), iron (Fe) and transferrin saturation index (TSI)). Among 432 included patients (mean age 59.8 years), 263 were men (60.9 %) and 169 women (39.1 %). P-CRC were identified in 221 patients (51.2 %) and no polyps (NP) in 211 patients (48.8 %). HFE mutations were identified in 43.8 % of the patients. C282Y/wt genotypic frequency was 6.8 % in the P-CRC group and 1.4 % in the NP group (p < 0.05). The allelic frequency was 3.8 versus 1.2 % (p < 0.05). For laboratory, all three iron biomarkers showed a statistically significant difference: mean Fe, 91.29 ± 34 for P-CRC and 80.81 ± 30.59 for NP group. Mean TSI for P-CRC was 24.95 ± 8.90 and 22.74 ± 8.79 for NP group. Mean SF 308.09 ± 536.32 for P-CRC and 177.55 ± 159.95 for NP group. In a multivariate logistic regression analysis, only male gender (odds ratio (OR) = 2.04, 1.29-3.22), SF (OR = 1.001, 1.0004-1.003) and Fe (OR = 1.01, 1.004-1.02) were related with the presence of CRC and adenoma. Men gender and raised serum iron biomarkers increase the risk of P-CRC.

Haplotype analysis of the HFE gene among populations of Northern Eurasia, in patients with metabolic disorders or stomach cancer, and in long-lived people.

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Mikhailova, S V; Babenko, V N; Ivanoshchuk, D E; Gubina, M A; Maksimov, V N; Solovjova, I G; Voevoda, M I

2016-06-17

Previously, it was shown that the HFE gene (associated with human hereditary hemochromatosis) has several haplotypes of intronic polymorphisms. Some haplotype frequencies are race specific and hence can be used in phylogenetic analysis. We assumed that analysis of Caucasoid patients-living now in Western Siberia and having diseases associated with dietary habits and metabolic rate-will allow us to understand the processes of possible selection during settling of the northern part of Asia. Haplotype analysis of Northern Eurasian native and recently settled ethnic groups was performed on polymorphisms rs1799945, rs1800730, rs1800562, rs2071303, rs1800708, rs1572982, rs2794719, rs807209, and rs2032451 of this gene. The CCA haplotype of the rs2071303, rs1800708, and rs1572982 was found to be associated with HLA-A2 (39 %) in Asian populations. Haplotype analysis for the rs1799945, rs1800730, rs1800562, rs2071303, rs1800708, and rs1572982 was performed on Russian patients with some metabolic disorders or stomach cancer and among long-lived people. Decreased frequencies of the TTA haplotype (T in rs2071303, T in rs1800708, and A in rs1572982) were observed in the groups of patients with diseases associated with overweight (fatty liver disease, type 2 diabetes mellitus, or metabolic syndrome + arterial hypertension) as compared with the control sample. We detected significant differences in this haplotype's frequency between the patients with type 2 diabetes mellitus and Russian adolescents, elderly citizens, and long-lived people (χ(2) P value = 0.003, 0.010, and 0.015, respectively). No significant differences in frequencies of the alleles with mutations in coding regions of the HFE gene (C282Y, H63D, and S65C) were detected between the analyzed patients (with stomach cancer, metabolic syndrome, fatty liver disease, or type 2 diabetes mellitus) and the control Caucasoid sample. Monophyletic origin of H63D (rs1799945) was confirmed in Caucasoids and Northern

Perfil antiinflamatorio del paricalcitol en el receptor de trasplante renal

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Javier Donate-Correa

2017-11-01

Conclusiones: La administración del paricalcitol a receptores de trasplante renal se asocia con efectos beneficiosos sobre su estado inflamatorio, lo que podría asociarse a un potencial beneficio clínico.

Papel de los anticuerpos antiplaquetarios en la infección viral: una revisión sistemática de la literatura

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Yenny M. Montenegro-Medina

2011-04-01

Conclusiones. Aunque la aparición de anticuerpos antiplaquetarios no se considera el único mecanismo que explica la trombocitopenia desarrollada en las infecciones virales mencionadas, de acuerdo con la literatura científica disponible, su presencia se asocia con la gravedad de la trombocitopenia y con potenciales implicaciones clínicas en los pacientes.

Hyperammonemic encephalopathy after urinary diversion. Diet therapy. Encefalopatía hiperamoniémica tras cistectomía radical y derivación urinaria. Tratamiento nutricional

OpenAIRE

Moriana, Miriam; Martinez-Ibañez, Juncal; Civera, Miguel; Martínez-Valls, José Francisco; Ascaso Gimilio, Juan Francisco

2016-01-01

La diabetes tipo 1 se asocia a otras enfermedades autoinmunes,con más frecuencia a tiroiditis linfocitaria o a celiaquía. En la última década se ha descrito algunos casos de encefalitis límbica asociados a diabetes tipo 1, tiroiditis u otros procesos autoinmunes, incluso en edad pediátrica.

CYBRD1 as a modifier gene that modulates iron phenotype in HFE p.C282Y homozygous patients.

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Pelucchi, Sara; Mariani, Raffaella; Calza, Stefano; Fracanzani, Anna Ludovica; Modignani, Giulia Litta; Bertola, Francesca; Busti, Fabiana; Trombini, Paola; Fraquelli, Mirella; Forni, Gian Luca; Girelli, Domenico; Fargion, Silvia; Specchia, Claudia; Piperno, Alberto

2012-12-01

Most patients with hereditary hemochromatosis in the Caucasian population are homozygous for the p.C282Y mutation in the HFE gene. The penetrance and expression of hereditary hemochromatosis differ largely among cases of homozygous p.C282Y. Genetic factors might be involved in addition to environmental factors. In the present study, we analyzed 50 candidate genes involved in iron metabolism and evaluated the association between 214 single nucleotide polymorphisms in these genes and three phenotypic outcomes of iron overload (serum ferritin, iron removed and transferrin saturation) in a large group of 296 p.C282Y homozygous Italians. Polymorphisms were tested for genetic association with each single outcome using linear regression models adjusted for age, sex and alcohol consumption. We found a series of 17 genetic variants located in different genes with possible additive effects on the studied outcomes. In order to evaluate whether the selected polymorphisms could provide a predictive signature for adverse phenotype, we re-evaluated data by dividing patients in two extreme phenotype classes based on the three phenotypic outcomes. We found that only a small improvement in prediction could be achieved by adding genetic information to clinical data. Among the selected polymorphisms, a significant association was observed between rs3806562, located in the 5'UTR of CYBRD1, and transferrin saturation. This variant belongs to the same haplotype block that contains the CYBRD1 polymorphism rs884409, found to be associated with serum ferritin in another population of p.C282Y homozygotes, and able to modulate promoter activity. A luciferase assay indicated that rs3806562 does not have a significant functional role, suggesting that it is a genetic marker linked to the putative genetic modifier rs884409. While our results support the hypothesis that polymorphisms in genes regulating iron metabolism may modulate penetrance of HFE-hereditary hemochromatosis, with emphasis on

Un estudio ecológico del voto socialista en el medio rural-urbano andaluz, 1999-2012

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Carmen Ortega

2015-01-01

Full Text Available Este artículo pretende contribuir a reforzar los estudios electorales en España, ampliando su especialización temática y metodológica, con la realización de un estudio ecológico del voto. En concreto, se exploran, desde un enfoque agregado, las relaciones entre el tipo de hábitat y el voto socialista en los distintos procesos celebrados en Andalucía, desde 1999 hasta 2012. Nuestro análisis empírico comprende dos aproximaciones: la primera ofrece una geografía del voto más descriptiva que explicativa, donde se muestra que tanto la participación como el voto al PSOE se asocia de forma negativa con el grado de urbanización; la segunda, mediante modelos de regresión espaciales, indaga las bases socioestructurales y muestra que el voto socialista se asocia a la inestabilidad y precariedad económica de las localidades ?fundamentalmente tasas de desempleo y de población agraria subsidiada?, especialmente en las elecciones generales y autonómicas.

Surface Tension and p−ρ−T Data for 1,1,1,3,3-Pentafluorobutane (HFC-365mfc) and 1,1,1,2,2,3,3-Heptafluoro-3-methoxy-propane (HFE-347mcc)

Czech Academy of Sciences Publication Activity Database

Klomfar, Jaroslav; Součková, Monika; Pátek, Jaroslav

2013-01-01

Roč. 58, č. 8 (2013), s. 2316-2325 ISSN 0021-9568 R&D Projects: GA ČR GA101/09/0010 Institutional support: RVO:61388998 Keywords : surface tension * density * HFC-365mfc * HFE-347mcc Subject RIV: BJ - Thermodynamics Impact factor: 2.045, year: 2013

Science.gov (United States)

Valladares, Macarena; Campos, Brianda; Zapata, Camila; Durán Agüero, Samuel; Obregón, Ana María

2016-11-29

Introducción: existen características respecto a los ritmos circadianos (ciclo sueño-vigilia), lo que genera un rasgo denominado cronotipo (madrugador o trasnochador). Se ha asociado el cronotipo vespertino a menos horas de sueño y hábitos alimentarios poco saludables. El cronotipo vespertino se asocia con un mayor riesgo de desarrollar obesidad.Objetivo: determinar la asociación del cronotipo con variables antropométricas en jóvenes de 18 a 25 años.Métodos: jóvenes (n = 65) (18 a 25 años), se les determinó el cronotipo (cuestionario de Horne-Ostberg) y mediciones antropométricas (peso, talla, porcentaje de grasa y perímetro de cintura). Resultados: los hombres con cronotipo trasnochador presentaron significativamente mayor perímetro de cintura (p = 0,03). Las mujeres con un porcentaje de grasa < 25% se asoció con cronotipo trasnochador (p = 0,05). Conclusiones: el cronotipo trasnochador se asocia a mayor perímetro de cintura y mayor porcentaje de grasa. El cronotipo constituye un nuevo foco para la prevención y el tratamiento de la obesidad.

Resultados de SPECT miocárdico y eventos cardiovasculares en dos servicios de Medicina nuclear de Bogotá durante 2011 a 2012

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Leonardo Cadavid

2014-03-01

Conclusiones: Un estudio SPECT miocárdico normal se asocia con incidencia reducida de eventos cardiovasculares mayores en el seguimiento a un año, aun en pacientes con características clínicas de alto riesgo.

The Effects of Degraded Digital Instrumentation and Control Systems on Human-system Interfaces and Operator Performance: HFE Review Guidance and Technical Basis

Energy Technology Data Exchange (ETDEWEB)

O' Hara, J.M.; W. Gunther, G. Martinez-Guridi

2010-02-26

New and advanced reactors will use integrated digital instrumentation and control (I&C) systems to support operators in their monitoring and control functions. Even though digital systems are typically highly reliable, their potential for degradation or failure could significantly affect operator performance and, consequently, impact plant safety. The U.S. Nuclear Regulatory Commission (NRC) supported this research project to investigate the effects of degraded I&C systems on human performance and plant operations. The objective was to develop human factors engineering (HFE) review guidance addressing the detection and management of degraded digital I&C conditions by plant operators. We reviewed pertinent standards and guidelines, empirical studies, and plant operating experience. In addition, we conducted an evaluation of the potential effects of selected failure modes of the digital feedwater system on human-system interfaces (HSIs) and operator performance. The results indicated that I&C degradations are prevalent in plants employing digital systems and the overall effects on plant behavior can be significant, such as causing a reactor trip or causing equipment to operate unexpectedly. I&C degradations can impact the HSIs used by operators to monitor and control the plant. For example, sensor degradations can make displays difficult to interpret and can sometimes mislead operators by making it appear that a process disturbance has occurred. We used the information obtained as the technical basis upon which to develop HFE review guidance. The guidance addresses the treatment of degraded I&C conditions as part of the design process and the HSI features and functions that support operators to monitor I&C performance and manage I&C degradations when they occur. In addition, we identified topics for future research.

A Survey on the HFE-related Technologies for the Improvements of Human Performance of Safety Personnel in Rail System

International Nuclear Information System (INIS)

Koo, I. S.; Park, G. O.; Suh, S. M.; Sim, Y. R.; Go, J. H.; Jeong, J. H.; Son, C. H.

2005-08-01

Many studies have shown that the most cases of rail accidents have occurred because of performing his/her tasks in inappropriate way. It is generally recognised that the rail system without human element could never be happened quite long time. So human element in rail system is going to be the major factor to the next tragic accident. This state-of-the-art report describes three major HFE-related technologies, training simulator, the integrated test facility for human factors engineering, and human performance evaluation system, that are used in the other industries including nuclear power industry for the purpose of increasing rail safety through out the improvement of human task performance. Base on this report, the way of developing those technologies that should be applied to the korean rail system is presented

A Survey on the HFE-related Technologies for the Improvements of Human Performance of Safety Personnel in Rail System

Energy Technology Data Exchange (ETDEWEB)

Koo, I. S.; Park, G. O.; Suh, S. M.; Sim, Y. R.; Go, J. H.; Jeong, J. H.; Son, C. H

2005-08-15

Many studies have shown that the most cases of rail accidents have occurred because of performing his/her tasks in inappropriate way. It is generally recognised that the rail system without human element could never be happened quite long time. So human element in rail system is going to be the major factor to the next tragic accident. This state-of-the-art report describes three major HFE-related technologies, training simulator, the integrated test facility for human factors engineering, and human performance evaluation system, that are used in the other industries including nuclear power industry for the purpose of increasing rail safety through out the improvement of human task performance. Base on this report, the way of developing those technologies that should be applied to the korean rail system is presented.

Déficit de testosterona en los pacientes en diálisis: diferencias según la técnica de diálisis

Directory of Open Access Journals (Sweden)

Secundino Cigarrán

2017-09-01

Conclusiones: Los niveles circulantes de testosterona en hombres en diálisis se asocian de manera independiente con la técnica de HD. Se puede concluir que, en la reducción de testosterona que acompaña de manera natural a la pérdida de masa muscular e inflamación, se asocia un nuevo factor que es la técnica dialítica. Se necesitan estudios para elucidar si la técnica per se favorece la eliminación de testosterona.

The Effects of Degraded Digital Instrumentation and Control Systems on Human-system Interfaces and Operator Performance: HFE Review Guidance and Technical Basis

International Nuclear Information System (INIS)

O'Hara, J.M.; Gunther, W.; Martinez-Guridi, G.

2010-01-01

New and advanced reactors will use integrated digital instrumentation and control (I and C) systems to support operators in their monitoring and control functions. Even though digital systems are typically highly reliable, their potential for degradation or failure could significantly affect operator performance and, consequently, impact plant safety. The U.S. Nuclear Regulatory Commission (NRC) supported this research project to investigate the effects of degraded I and C systems on human performance and plant operations. The objective was to develop human factors engineering (HFE) review guidance addressing the detection and management of degraded digital I and C conditions by plant operators. We reviewed pertinent standards and guidelines, empirical studies, and plant operating experience. In addition, we conducted an evaluation of the potential effects of selected failure modes of the digital feedwater system on human-system interfaces (HSIs) and operator performance. The results indicated that I and C degradations are prevalent in plants employing digital systems and the overall effects on plant behavior can be significant, such as causing a reactor trip or causing equipment to operate unexpectedly. I and C degradations can impact the HSIs used by operators to monitor and control the plant. For example, sensor degradations can make displays difficult to interpret and can sometimes mislead operators by making it appear that a process disturbance has occurred. We used the information obtained as the technical basis upon which to develop HFE review guidance. The guidance addresses the treatment of degraded I and C conditions as part of the design process and the HSI features and functions that support operators to monitor I and C performance and manage I and C degradations when they occur. In addition, we identified topics for future research.

LA INSATISFACCIÓN LABORAL COMO FACTOR DEL BAJO RENDIMIENTO DEL TRABAJADOR

OpenAIRE

Granda Carazas, Segundo Eloy

2014-01-01

El tema "la insatisfacción laboral como factor del bajo rendimiento del trabajador" es importante, ya que se puede constatar que en algunas organizaciones, pese a sus significativos esfuerzos para ampliar y modernizar su infraestructura, afrontan problemas de rendimiento laboral. Este artículo se orienta a determinar en qué medida la insatisfacción laboral se asocia al bajo rendimiento laboral en una organización. Como factores constituyentes de la insatisfacción laboral se considerar...

El síndrome metabólico ¿Cómo abordar el problema?

Directory of Open Access Journals (Sweden)

Alain Francisco Morejón Giraldoni

2011-08-01

Full Text Available El síndrome metabólico (SM es una entidad clínica cuya prevalencia mundial se incrementa año tras año, lo que lo convierte en un serio problema de salud pública. Se considera que este aumento se debe, por un lado, al estilo de vida sedentario, y por el otro, a la obesidad, por lo que se asocia con un incremento del riesgo de padecer enfermedad cardiovascular (ECV y diabetes (DM tipo II.

Análisis de los factores que inciden en el consumo de una nueva bebida probiótica elaborada a partir de Aguamiel. Nanacamilpa, Tlaxcala

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Alicia Lucrecia Yáñez Moneda

2016-03-01

Full Text Available El aguamiel es una de las bebidas con más tradición en la cultura mexicana. Su nombre se asocia con el pulque, pero pocas personas conocen realmente cuáles son sus atributos nutrimentales. El aguamiel cuenta con propiedades que inhiben el crecimiento de bacterias patógenas y estimulan el crecimiento de la flora intestinal. Con todas estas propiedades se puede considerar al aguamiel como una bebida prebiótica; sin embargo, a las bebidas probióticas se les asocia con las bacterias lácticas. El objetivo de esta investigación no experimental, cuantitativa, descriptiva y transversal simple, consiste en analizar los factores que inciden en el consumo de una nueva bebida probiótica elaborada a partir del aguamiel, en la comunidad de Nanacamilpa en el estado de Tlaxcala. Los resultados demuestran que dentro de las variables analizadas, el factor que más incide en su comercialización es la pérdida de hábitos de consumo hacia el aguamiel como bebida tradicional mexicana

Servicio farmacéutico de deshabituación al tabaco

OpenAIRE

March Pujol, Marian; Travé i Mercadé, Pere; Via Sosa, Ma. de los Ángeles; Fuentes Almendras, Miriam; Badía Palacín, Josefa

2012-01-01

Se describe qué es el tabaquismo, con que enfermedades se asocia, el proceso de deshabituación tabáquica,fases del mismo e intervenciones farmacéuticas. Materiales y herramientas necesarios para prestar el servicio de deshabituación al tabaco. Técnica, tests de valoración, plan de acción y registros. Manejo de la terapia sustitutiva de la nicotina.

Disfunción muscular respiratoria en pacientes llevados a cirugía cardiovascular

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Diana Cáceres

2016-09-01

Conclusiones: Los pacientes llevados a la cirugía cardiovascular tienen una insospechada disfunción de los músculos respiratorios que empeora con la cirugía y la hospitalización, que se asocia a un incremento del riesgo de complicaciones respiratorias.

Burnout subtypes and their clinical implications: a theoretical proposal for specific therapeutic approaches

OpenAIRE

Montero-Marín, Jesús; Prado-Abril, Javier; Demarzo, Marcelo M. P.; García-Toro, Mauro; García-Campayo, Javier

2016-01-01

El burnout se asocia con un peor estatus de salud percibida, trastornos psicosomáticos y enfermedades físicas. El objetivo del presente trabajo es articular una propuesta teórica comprehensiva de intervención terapéutica sensible a las diferentes m

MOLA HIDATIDIFORME PARCIAL CON FETO VIVO DEL SEGUNDO TRIMESTRE

OpenAIRE

Juárez Azpilcueta, Arturo; Islas Domínguez, Luis; Durán Padilla, Marco Antonio

2010-01-01

La mola hidatidiforme es un embarazo que se caracteriza por una degeneración hidrópica de las vellosidades coriales y habitualmente la ausencia del feto. La mola parcial se caracteriza por ser resultado de una triploidía diándrica y por la presencia de cambios hidatiformes progresivos lentos con capilares vellosos funcionantes, que afectan solamente a algunas de las vellosidades; se asocia con un feto o embrión anormal identifcable (vivo o muerto), membranas o eritrocitos fetales. Se analiza ...

Alimentación saludable y autopercepción de salud

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Gemma Blázquez Abellán

2016-10-01

Conclusiones: En mayores de 50 años el nivel de salud autopercibida se asocia al cumplimiento de los criterios de una alimentación saludable, lo cual es independiente de otros hábitos de salud y de las principales variables sociodemográficas.

Reduction of body iron in HFE-related haemochromatosis and moderate iron overload (Mi-Iron): a multicentre, participant-blinded, randomised controlled trial.

Science.gov (United States)

Ong, Sim Y; Gurrin, Lyle C; Dolling, Lara; Dixon, Jeanette; Nicoll, Amanda J; Wolthuizen, Michelle; Wood, Erica M; Anderson, Gregory J; Ramm, Grant A; Allen, Katrina J; Olynyk, John K; Crawford, Darrell; Ramm, Louise E; Gow, Paul; Durrant, Simon; Powell, Lawrie W; Delatycki, Martin B

2017-12-01

The iron overload disorder hereditary haemochromatosis is most commonly caused by HFE p.Cys282Tyr homozygosity. In the absence of results from any randomised trials, current evidence is insufficient to determine whether individuals with hereditary haemochromatosis and moderately elevated serum ferritin, should undergo iron reduction treatment. This trial aimed to establish whether serum ferritin normalisation in this population improved symptoms and surrogate biomarkers. This study was a multicentre, participant-blinded, randomised controlled trial done at three centres in Australia. We enrolled people who were homozygous for HFE p.Cys282Tyr, aged between 18 and 70 years, with moderately elevated serum ferritin, defined as 300-1000 μg/L, and raised transferrin saturation. Participants were randomly assigned, via a computer-generated random number, to undergo either iron reduction by erythrocytapheresis (treatment group) or sham treatment by plasmapheresis (control group). Randomisation was stratified by baseline serum ferritin (cognitive subcomponent (-3·6, -5·9 to -1·3, p=0·0030), but not in the physical (-1·90 -4·5 to 0·63, p=0·14) and psychosocial (-0·54, -1·2 to 0·11, p=0·10) subcomponents. No serious adverse events occurred in either group. One participant in the control group had a vasovagal event and 17 participants (14 in the treatment group and three in the control group) had transient symptoms assessed as related to hypovolaemia. Mild citrate reactions were more common in the treatment group (32 events [25%] in 129 procedures) compared with the control group (one event [1%] in 93 procedures). To our knowledge, this study is the first to objectively assess the consequences of iron removal in individuals with hereditary haemochromatosis and moderately elevated serum ferritin. Our results suggest that serum ferritin normalisation by iron depletion could be of benefit for all individuals with hereditary haemochromatosis and elevated serum

Factores asociados a complicaciones de yeyunostomía

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H. Medina-Franco

2013-04-01

Conclusiones: La yeyunostomía se asocia a una elevada frecuencia de complicaciones, tanto médicas como quirúrgicas. Si bien se ha establecido como una mejor alternativa a nutrición parenteral, deberá tomarse en cuenta la morbilidad asociada a la misma antes de establecer su utilización rutinaria como medio de aporte nutricional, particularmente en pacientes con factores asociados al desarrollo de las mismas.

Treatment with Insulin and Heparin in Severe Hypertriglyceridemia

OpenAIRE

Masson, W; Fernández-Otero, L; Siniawski, D; Arias, A; Maritano, J; Ortiz, MI

2012-01-01

La hipertrigliceridemia severa se asocia con pancreatitis aguda y suele producirse por una deficiencia genética o adquirida en la actividad de la lipoproteín lipasa (LPL). El tratamiento habitual en pacientes ambulatorios se basa en una alimentación saludable, ejercicio físico, control del peso, complementos de omega 3 y fármacos como los fibratos y la niacina. Ante situaciones de hipertrigliceridemia severa asociados o no a pancreatitis, se recomienda el tratamiento con insulina y/o heparina...

Dysthyroid ophthalmopathy associated with hypothyroidism

OpenAIRE

Maciá-Bobes, C.; Ronzón-Fernández, A.

2007-01-01

Caso clínico: La oftalmopatía por enfermedad de Graves (exoftalmos, infiltración muscular y palpebral) se asocia casi sistemáticamente a hipertiroidismo. Paciente diagnosticada de hipotiroidismo subclínico y tratada adecuadamente con tiroxina oral. Unos meses después desarrolla un exoftalmos bilateral y simultáneamente presenta anticuerpos séricos anti-receptor de TSH positivos. Se suspende entonces el tratamiento con tiroxina, y se comprueba que el hipotiroidismo ha progresado hasta hacerse ...

Prevalence of C282Y and H63D mutations in the HFE gene of Brazilian individuals with clinical suspicion of hereditary hemochromatosis Prevalência das mutações C282Y e H63D no gene HFE em indivíduos brasileiros com suspeita clínica de hemocromatose hereditária

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Alessandro C. S. Ferreira

2008-10-01

Full Text Available Classical hereditary hemochromatosis is a recessive autosomal disease related to a systemic iron overload that is frequently related to C282Y and H63D mutations in the HFE gene. In Brazil, reports on HFE gene mutation frequencies are rare, mainly in regards to a representative sample population. This study intended to determine the prevalence of C282Y and H63D mutations among individuals with clinical suspicion of hereditary hemochromatosis. A total of 1955 patients were studied with C282Y and H63D mutations being detected by the polymerase chain reaction technique followed by enzymatic restriction. The sample consisted of 76.6% men and 23.4% women. The highest percentage of analyzed individuals (56.9% was concentrated in the 41 to 60-year-old age group. Although there were no genic or genotypic differences between genders, a higher number of over 60-year-old women was observed. The C282Y mutation was found as homozygous in 2.9% of the cases and as heterozygous in 10.1%, while the H63D was homozygous in 4.3% and heterozygous in 30.6%. The C282Y and H63D mutant allele frequencies were 0.079 and 0.196, respectively. The highest frequency was observed for H63D which was in genetic equilibrium. This work is important to determine the genetic profile of the population with hereditary hemochromatosis in Brazi.A hemocromatose hereditária clássica (HH é uma doença autossômica recessiva caracterizada por uma sobrecarga sistêmica de ferro, a qual está freqüentemente relacionada às mutações C282Y e H63D no gene HFE. No Brasil, registros das freqüências das mutações no gene HFE são raros, principalmente envolvendo uma amostra representativa da população. Este estudo teve como objetivo a determinação da prevalência das mutações C282Y e H63D em indivíduos com suspeita clínica de HH. Para isto, foram estudados 1955 pacientes para os quais as mutações C282Y e H63D foram pesquisadas pela técnica de Reação em Cadeia da Polimerase

Papel de la testosterona y el cortisol en el síndrome metabólico y la diabetes mellitus tipo 2 Role of testosterone and cortisol in metabolic syndrome and type 2 diabetes mellitus

OpenAIRE

Aimée M. Álvarez Álvarez; Roberto M. González Suárez; Miguel A. Marrero Falcón

2010-01-01

INTRODUCCIÓN: el síndrome metabólico y la diabetes mellitus tipo 2 son trastornos metabólicos que han sido ampliamente abordados en la literatura científica por su alta incidencia, así como la alta morbilidad y mortalidad que a ellos se asocia. En los últimos años se han explorado nuevos elementos de posible impacto en su fisiopatogenia, dentro de los que se destacan los esteroides sexuales y los glucocorticoides. En este trabajo se revisaron y comentaron los conocimientos más actuales sobre ...

Cuantificación de la densidad de capilares sanguíeos en el nodo sinusal de pacientes con fibrilación auricular cróica

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Aquilino Hurlé

2008-07-01

Conclusiones: La FA crónica se asocia a una reducción significativa de la microcirculación del nodo sinusal. Esto apoyaría la hipótesis de que la isquemia del nodo sinusal podría resultar relevante en la patogenia de dicha arritmia.

La precariedad laboral medida de forma multidimensional: distribución social y asociación con la salud en Cataluña

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Joan Benach

2015-09-01

Conclusiones: La precariedad laboral se asocia con peor salud en la población trabajadora. Deberían incluirse preguntas sobre precariedad e indicadores de salud en las encuestas de condiciones de trabajo para poder realizar una posterior vigilancia y un análisis de las desigualdades en salud.

COMPORTAMENTO DE RISCO À SAÚDE DE ADOLESCENTES ESCOLARES

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Franck Nei Monteiro Barbosa

2016-01-01

Full Text Available El objetivo de este estudio fue describir los comportamientos de riesgo a la salud entre adolescentes de educación secundaria en las escuelas públicas en una ciudad del nordeste de Brasil. Estudio epidemiológico, transversal, de base poblacional con una muestra aleatoria simple. Para obtener los datos, hemos utilizado cuestionarios estructurados y validados. Para el análisis de los datos, se utilizó el test de Chi cuadrado, con un nivel de significación del 5%. Se ha encontrado que la inactividad física está asociada con el sexo, la edad y el periodo de estudio. El consumo de tabaco se asocia significativamente con el sexo, la edad y el periodo de estudio y consumo de alcohol al periodo de estudio y edad. En cuanto a los malos hábitos alimenticios, el consumo de alimentos fritos se asocia con el período de estudio y los dulces y las bebidas gaseosas con el período de estudio y la edad. Encontramos una alta prevalencia de conductas de riesgo entre los adolescentes, además es necesario implementar políticas para mejorarse la salud de la población.

Experiments on HFE-7100 pool boiling at atmospheric pressure in horizontal narrow spaces

Energy Technology Data Exchange (ETDEWEB)

Guglielmini, G.; Misale, M.; Priarone, A. [Universita degli Studi di Genova (Italy). DIPTEM - Sezione di Termoenergetica e Condizionamento Ambientale

2009-07-01

Experiments were performed to examine the pool boiling heat transfer and critical heat flux on a smooth copper circular surface, confined by a face-to-face parallel unheated surface, by changing the gap between the surfaces and the unheated surface diameter. Pool boiling data at atmospheric pressure were obtained for saturated HFE-7100. The gap values investigated, between the boiling surface and the adiabatic one, were s 0.5, 1.0, 2.0, 3.5 mm. To confine the boiling surface, two different Plexiglas plates were used: the former characterised by a diameter D = 60 mm, large as the overall test section support, the latter characterised by a diameter D = 30 mm, large to cover only copper boiling surface (d = 30 mm). For each configuration, boiling curves were obtained up to the thermal crisis. For both different types of confinement, it was observed that the boiling curves match at low wall superheat, except for s = 0.5 mm, 1 mm. However, at high wall superheat, a drastic reduction in heat transfer as well as CHF appears decreasing the channel width s; for all gap sizes, this reduction is less pronounced for the smaller confinement wall (D = 30 mm). Instead, at low wall superheat for gap of 0.5 and 1.0 mm, the heat transfer coefficient is higher for diameter disc of 60 mm. CHF data were also compared with a literature correlation (Misale and al., 2009). (author)

Características histopatológicas del adenocarcinoma gástrico en pacientes mexicanos. Experiencia de 10 años en el Hospital Juárez de México

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M.G. Martínez-Galindo

2015-01-01

Conclusiones: Este es el primer estudio en nuestra población que hace diferencias entre los tipos histológicos del adenocarcinoma. El subtipo de adenocarcinoma gástrico más frecuente en nuestra población fue el difuso, el cual se asocia a peor pronóstico.

Seguimiento a largo plazo de pacientes con disfunción ventricular izquierda intervenidos de sustitución valvular aórtica. Experiencia en nuestra institución

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Gemma Candela-Navarro

2016-07-01

Conclusiones: La sustitución valvular aórtica es una opción segura, eficaz y duradera en pacientes con disfunción ventricular izquierda. Se asocia a una mejoría en la clase funcional y fracción de eyección, con una perspectiva de futuro excelente.

Colecistitis enfisematosa, revisión bibliográfica y presentación de tres casos

OpenAIRE

Escobar, Fernando; Vega, Neil Valentín; Valbuena, Eduart Iván

2015-01-01

La colecistitis enfisematosa es una rara forma de presentación de la colecistitis aguda, caracterizada por la presencia de gas en la pared, en la luz o ambas, la cual puede evolucionar a colecistitis gangrenosa y posteriormente a peritonitis. Se asocia con una alta tasa de morbilidad y mortalidad. Se presentan tres casos clínicos de hombres adultos mayores, que presentaron dolor abdominal con síntomas gastrointestinales y signos de respuesta inflamatoria sistémica. Se les practicó tomografía ...

Adolescentes con autolesiones e ideación suicida: un grupo con mayor comorbilidad y adversidad psicosocial

OpenAIRE

Mayer Villa, Pablo Adolfo; Morales Gordillo, Nadia; Victoria Figueroa, Gamaliel; Ulloa Flores, Rosa Elena

2016-01-01

La creciente prevalencia de conductas suicidas en adolescentes se ha convertido en un problema de salud pública. Existen varios factores asociados con este tipo de conductas, tales como: síntomas depresivos y ansiosos, consumo de sustancias nocivas, trastornos de conducta, violencia familiar, negligencia y abuso sexual en la infancia. Otro factor importante que se asocia con la presencia del comportamiento suicida son las autolesiones, las cuales pueden definirse como conductas deliberadas de...

Complicaciones asociadas a la hiperglucemia en pacientes trasplantados de hígado

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Carlos Esteban Builes Montaño

2014-07-01

Conclusión: La hiperglucemia durante las primeras 48 h después de un trasplante pareciera ser un fenómeno esperable en la mayoría de pacientes y no se asocia a un mayor riesgo de rechazo, infección y no impacta en el tiempo de estancia hospitalaria.

PROMETHEE: A NEW APPROACH THROUGH FUZZY MATHEMATICAL PROGRAMMING

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Mariano Jiménez López

2004-03-01

Full Text Available

Los métodos multicriterios PROMETHEE se basan en las evaluaciones borrosas entre los diferentes pares de alternativas para cada criterio. PROMETHEE II asocia un número a cada acción, y la indiferencia entre dos alternativas solo ocurre cuando los flujos correspondientes son estrictamente iguales. PROMETHEE III asocia a cada acción un intervalo y dos acciones son consideradas indiferentes cuando ellas están muy cerca entre sí. PROMETHEE V aplica la Programación Lineal Entera para seleccionar el mejor subconjunto de alternativas. El objetivo es maximizar la suma de PROMETHEE II, sujeto a un conjunto de restricciones que normalmente incluyen alguna restricción financiera. En el presente trabajo se ha considerado para que el modelo sea más realista, que algunos restricciones sean suaves y que algunos coeficientes se estimen por los números borrosos. Se aplica la Programación Lineal en Enteros Borrosa, utilizando la suma de los resultados de PROMETHEE III como función de objetivo. La indiferencia introducida por PROMETHEE III permite encontrar el subconjunto de alternativas no superior y verificar la restricción suavizada. Se ilustra el método propuesto a través de un ejemplo usado en el PROMETHE V original, se comparan los dos procedimientos.

PROMETHEE: A NEW APPROACH THROUGH FUZZY

Directory of Open Access Journals (Sweden)

Mariano Jiménez López

2004-01-01

Full Text Available

Los métodos multicriterios PROMETHEE se basan en las evaluaciones borrosas entre los diferentes pares de alternativas para cada criterio. PROMETHEE II asocia un número a cada acción, y la indiferencia entre dos alternativas solo ocurre cuando los flujos correspondientes son estrictamente iguales. PROMETHEE III asocia a cada acción un intervalo y dos acciones son consideradas indiferentes cuando ellas están muy cerca entre sí. PROMETHEE V aplica la Programación Lineal Entera para seleccionar el mejor subconjunto de alternativas. El objetivo es maximizar la suma de PROMETHEE II, sujeto a un conjunto de restricciones que normalmente incluyen alguna restricción financiera. En el presente trabajo se ha considerado para que el modelo sea más realista, que algunos restricciones sean suaves y que algunos coeficientes se estimen por los números borrosos. Se aplica la Programación Lineal en Enteros Borrosa, utilizando la suma de los resultados de PROMETHEE III como función de objetivo. La indiferencia introducida por PROMETHEE III permite encontrar el subconjunto de alternativas no superior y verificar la restricción suavizada. Se ilustra el método propuesto a través de un ejemplo usado en el PROMETHE V original, se comparan los dos procedimientos.

Disincronía ventricular izquierda en la estimulación septal prolongada

OpenAIRE

Ferrando-Castagnetto, Federico; Ricca-Mallada, Roberto; Vidal, Alejandro; Martínez, Fabián; Ferrando, Rodolfo

2016-01-01

La estimulación por marcapasos se asocia con eventos adversos graves. En la siguiente serie de casos se evaluó la disincronía mecánica intraventricular izquierda (DMVI) en la estimulación endocárdica prolongada del ventrículo derecho a nivel septal. Se estudiaron 6 personas con marcapasos implantados no antes de un año utilizando SPECT gatillado con 99mTc-MIBI y análisis de fase en reposo. Se registraron variables clínicas, duración del QRS, tasa y modo de estimulación ventricular, presencia ...

Obesidad y menopausia Obesity and menopause

OpenAIRE

I. Pavón de Paz; C. Alameda Hernando; J. Olivar Roldán

2006-01-01

La menopausia es una de las etapas críticas en la vida de la mujer en la que se favorece la ganancia de peso y el desarrollo o agravamiento de la obesidad. Es en ésta época cuando se encuentra la prevalencia de obesidad más elevada. Las causas de éste problema son múltiples, unas se relacionan claramente con el hipoestrogenismo y otras dependen de la edad, condicionando un aumento de la ingesta y una disminución del gasto energético. Esta ganancia ponderal se asocia a consecuencias adversas p...

Efecto del Síndrome Metabólico inducido por una dieta rica en fructosa sobre el tejido óseo

OpenAIRE

Felice, Juan Ignacio

2014-01-01

Introducción. El Síndrome Metabólico (SM) se define como un conjunto de anormalidades fisiológicas y metabólicas que incluyen obesidad central y global, tolerancia a la glucosa alterada con insulinorresistencia, dislipidemia e hipertensión. Desde su descripción en 1988, la incidencia del SM ha aumentado dramáticamente, y se ha reportado que se presenta en más del 20% de la población adulta en los países en desarrollo. La prevalencia del SM aumenta con la edad y se asocia con alto riesgo de Di...

ASPECTOS REPRODUCTIVOS EN MUJERES PORTADORAS DE MUTACIONES GENÉTICAS BRCA

OpenAIRE

Dr. Octavio Peralta; Dr. Tulio Rodríguez; Dra. Adela Camus

2017-01-01

Se analizan diferentes aspectos reproductivos en mujeres portadoras de mutaciones genéticas BRCA. Se revisa la evidencia científica del riesgo que agrega el uso de anticoncepción hormonal a mujeres con diferentes niveles de riesgo concluyendo que con las formulaciones recientes después del 2010 no hay aumento del riesgo de cáncer de mama. En portadoras de mutaciones BRCA, el uso prolongado antes de los 25 años se asocia a un leve mayor riesgo de diagnóstico temprano de cáncer de mama. Se a...

Leucemia viral felina simultánea con otras patologías en tres casos clínicos diferentes

OpenAIRE

Ortiz A, José F

2011-01-01

La leucemia viral felina (ViLeF) es una patología, que se asocia con la presentación de varias enfermedades; el artículo presenta tres casos de pacientes cada uno con patologías diferentes que a su vez fueron positivos a ViLeF; no se descarta que esta enfermedad esté relacionada o sea la causa de las tres patologías, en el primer caso se encontró una anemia arregenerativa, en el otro, un carcinoma mamario y en el último, un proceso compatible con una peritonitis felina. Se describen la sintom...

Determinantes sociales y estado de la dentición en escolares de San Felipe del Progreso, estado de México

OpenAIRE

Eveline Contreras Huerta; Cristina Sifuentes Valenzuela; Javier de la Fuente-Hernández; Laura Susana Acosta-Torres; María del Carmen Villanueva Vilchis

2015-01-01

Los determinantes sociales son aquellas condiciones sociales de desarrollo que impactan la salud. Existe asociación entre algunos problemas bucales con una inequitativa distribución económica. Objetivo : Identificar la asocia - ción entre algunos determinantes sociales y la experiencia de caries en niños de San Felipe del Progreso. Metodología: Estudio transversal. Se seleccionaron 83 niños de 6 a 12 años y se les aplicó un cuestionario socio-demográfico. Se evaluó la experiencia de carie...

Presentación sistémica de Aspergillus spp con semiología neurológica en un Pastor Alemán: informe de un caso clínico

OpenAIRE

Hernández Tapia, Ana Laura; Santoscoy Mejía, Eduardo Carlos; Ramírez Lezama, José; Cervantes Olivares, Roberto A.; Quiroz Mercado, Joaquín Arturo

2010-01-01

La infección del sistema nervioso en el perro es poco común; posibles causas son Aspergillus spp, Cryptococcus neoformans, Blastomyces dermatidis y Coccidioides immitis. La infección por Aspergillus spp afecta al aparato respiratorio y en pocas ocasiones se presenta de manera diseminada. Sin embargo, en el Pastor Alemán hay mayor incidencia de éste, pues dicha infección se asocia con una deficiencia inmunológica. Se describe el caso de una perra de raza Pastor Alemán, de 1.5 años de edad, ref...

Manejo endodóntico en pacientes con riesgo de osteonecrosis asociada a bifosfonatos: Scoping review

OpenAIRE

Rojas, Carolina; Rivera, Carolina; Villanueva, Julio; Yanine, Nicolás

2015-01-01

El objetivo de este artículo es revisar la evidencia disponible que asocia la aparición de osteonecrosis maxilar por bifosfonatos (OMB) al tratamiento endodóntico, con sus eventuales consideraciones terapéuticas. Se realizó una búsqueda amplia de la literatura en bases de datos como MEDLINE, EMBASE y CENTRAL. Se definieron previamente criterios de selección que consideraran la endodoncia y la OMB. Se extrajo la evidencia relevante de los artículos que cumplieron con los criterios de selección...

Prevalencia de la desviación vertical disociada en pacientes con estrabismo secundario a mala visión versus estrabismo congénito con ambliopía

OpenAIRE

Pérez Pérez, José Fernando; Guido Jiménez, Marilú Anahí; Arroyo Yllanes, María Estela

2015-01-01

La desviación vertical disociada (DVD) se asocia a endotropía congénita; también se ha descrito en otros tipos de estrabismo como los secundarios. Objetivo: Establecer la frecuencia de DVD en pacientes con estrabismo secundario a mala visión. Material y método: Estudio prospectivo que incluyó a pacientes con estrabismo secundario a mala visión y como grupo control a pacientes con estrabismo y ambliopía estrábica profunda. Resultados: Se incluyeron 57 pacientes, el 77% fueron mujeres....

Effectiveness of Clinical Diagnosis in Lesions by HPV in Mouth. Useful Clinical Criteria

OpenAIRE

Josué Roberto Bermeo Escalona; Blanca Silvia González López; Eva Ramón Gallegos; Hugo Mendieta Zerón

2015-01-01

La infección por virus del papiloma humano (vph) en boca se asocia con lesiones como hiperplasia epitelial multifocal (hem), verruga vulgar (vv) y condiloma acuminado (ca). En este sentido, se evaluó la eficacia del diagnóstico clínico en lesiones por vph en boca y se propusieron criterios útiles para su diagnóstico. Los resultados sugieren que la evaluación clínica no permite diferenciar las lesiones. Las variables clínicas encontradas para el diagnóstico de hem fueron edad y presencia de le...

BAJO RIESGO DE DÉFICIT ATENCIONAL / HIPERACTIVIDAD EN NIÑOS AYMARÁS: IMPLICANCIAS GENÉTICAS, ANTROPOLÓGICAS Y CULTURALES

OpenAIRE

Rothhammer, Paula; Carrasco, Ximena; Henríquez, Hugo; Andrade, Claudia; Valenzuela, Mario; Aboitiz, Francisco; Rothhammer, Francisco

2005-01-01

Se estudió la distribución de puntajes en la Escala de Conners que se utiliza para diagnosticar el trastorno por déficit atencional/hiperactividad (TDAH) en niños del Liceo Agrícola "José Abelardo Núñez", ubicado en San Miguel de Azapa, Arica, Chile, con el propósito de desarrollar estrategias de diagnóstico precoz para prevenir este trastorno, que se asocia frecuentemente a conductas de alto riesgo, como el uso de sustancias adictivas. Las niñas y varones aymarás obtuvieron puntajes signific...

ROGERS SU PENSAMIENTO PROFESIONAL Y SU FILOSOFÍA PERSONAL

Directory of Open Access Journals (Sweden)

Gina Pezzano de Vengoechea

2001-01-01

Full Text Available Carl Rogers denominó a su enfoque psicológico «Psicoterapia centrada en el cliente» y se asocia a la Psicología Humanista, que dignifica y valora el esfuerzo de la persona por desarrollar sus potencialidades. En esta ponencia se describen las ventajas y alcances de este enfoque, así como las limitaciones que muestra su empleo en medios socioeconómicos en desventaja. De igual manera, se analizan las enseñanzas más significativas de este psicoterapeuta acerca de las relaciones entre los individuos.

Características de las gestantes diabéticas hospitalizadas en el Complejo Asistencial Universitario de Palencia (CAUPA). Análisis del período 2001-2015

OpenAIRE

Moreno Aroca, Ricardo

2017-01-01

La Diabetes Mellitus (DM) es la alteración metabólica que más frecuentemente se asocia a la gestación1. La DM Gestacional (DMG) se define como una intolerancia a los carbohidratos, de severidad variable, que se diagnostica por primera vez en el curso del embarazo, independientemente del tiempo de evolución, necesidad de insulina, grado de trastorno metabólico o persistencia tras el embarazo2. Está relacionada con complicaciones maternas, fetales y neonatales, que son más habituales en los hij...

Uso y Abuso de Substancias Psicoactivas en Colombia. XIII Exposición Temporal.

Directory of Open Access Journals (Sweden)

Hugo Sotomayor Tribín

2007-06-01

El yopo (Anadenanthera peregrina, como psicomimético, o alucinógeno, que hoy se asocia a las culturas indígenas de la Orinoquia y de los u´was de la cordillera Oriental fue muy usado por los muescas. Esta planta de poder se usa como un polvo y mezclado con cales resultantes de la trituración de la conchas de caracoles de agua dulce se inhala a través de unos huesos de aves en las ceremonias de curación presididas por los chamanes...

Consumo de alcohol y contextos de desarrollo en la adolescencia

OpenAIRE

Rubio González, Antonia

2016-01-01

Los patrones de consumo de alcohol en España se han modificado en los últimos años, y aunque el consumo de alcohol per cápita ha ido descendiendo ligeramente en las últimas décadas, su prevalencia actual entre los adolescentes y las mujeres es alta. Se ha constatado que el consumo abusivo de alcohol en la adolescencia se asocia a numerosas consecuencias negativas, como la continuidad en su consumo y el de otras drogas en la adultez, los problemas académicos, las relaciones sexu...

Disfagia asociada a la enfermedad de Parkinson

OpenAIRE

Rodríguez Alonso, Alexandra

2017-01-01

La disfagia orofaríngea es un síntoma que se asocia a la enfermedad de Parkinson, se define como la dificultad o el impedimento al avance normal del bolo alimenticio desde la cavidad oral hasta el estómago, contribuyendo a una deglución ineficaz e insegura. Este proyecto de investigación tiene como objetivo principal detectar disfagia en pacientes con Enfermedad de Parkinson. Se realizó una encuesta que fue distribuida entre los EP que acuden a rehabilitación a la Asociación de Parkinson V...

Susceptibilidad antibiótica de Helicobacter pylori : un estudio de prevalencia en pacientes con dispepsia en Quito, Ecuador

OpenAIRE

Reyes Ch, Jorge; Guzmán, Katherine; Morales, Eduardo; Villacís, José; Pazmiño Quirós, Galo Fernando; Pacheco Tigselema, Rosa Eugenia; Escalante, Luis Santiago

2017-01-01

Resumen Introducción: el Helicobacter pylori se asocia con patologías gastrointestinales, el incremento en la resistencia a los antibióticos utilizados para su erradicación es alarmante a nivel mundial. En este estudio se determinó la susceptibilidad a 5 antibióticos utilizados en la terapia de erradicación de H. pylori aislado de una población adulta con dispepsia recurrente en Quito, Ecuador. Materiales y métodos : previa aceptación del consentimiento informado, se tomaron biopsias de cu...

Efecto de los inotrópicos sobre la mortalidad en falla cardiaca aguda. Metaanálisis en red de ensayos clínicos

OpenAIRE

Juan M. Sénior; Edison Muñoz; James Díaz

2017-01-01

Introducción: en pacientes con falla cardiaca aguda es necesario el uso de inotrópicos para lograr su estabilización. Objetivo: definir cuál de los medicamentos inotrópicos se asocia con menor mortalidad. Metodología: se realizó un metaanálisis en red con la aproximación frecuentista. La búsqueda sistemática incluyó PUBMED, EMBASE, CENTRAL, DARE, Epistemonikos, SieELO, LILACS y OpenGray. Se incluyeron ensayos clínicos con asignación aleatoria en pacientes con falla cardiaca aguda que re...

Optical studies of CdSe/HgSe and CdSe/Ag2Se core/shell nanoparticles embedded in gelatin

International Nuclear Information System (INIS)

Azhniuk, Yu M; Dzhagan, V M; Valakh, M Ya; Raevskaya, A E; Stroyuk, A L; Kuchmiy, S Ya; Zahn, D R T

2008-01-01

CdSe/HgSe and CdSe/Ag 2 Se core-shell nanoparticles are obtained by colloidal synthesis from aqueous solutions in the presence of gelatin. Optical absorption, luminescence, and Raman spectra of the nanoparticles obtained are measured. The variation of the optical spectra of CdSe/HgSe and CdSe/Ag 2 Se core-shell nanoparticles with the shell thickness is discussed. Sharp non-monotonous variation of the photoluminescence spectra at low shell coverage is observed.

Angiografía del día siguiente tras fibrinólisis exitosa frente al tratamiento convencional, en el síndrome coronario agudo con elevación del segmento ST, fibrinolisado

Directory of Open Access Journals (Sweden)

José D. Cascón-Pérez, MD

2012-01-01

Conclusiones: la angiografía del día siguiente se asocia con una reducción de la estancia media respecto al tratamiento convencional. Además, parece mostrar una tendencia (no significativa de reducción de mortalidad al año, sin que aumente el número de complicaciones hemorrágicas.

Salud del hombre mayor: más allá de la urología

Directory of Open Access Journals (Sweden)

Dr. Carlos E. García B.

2014-01-01

Hay evidencias de que la sobrevida de los hombres en casa de reposo es menor y su conducta es más disruptiva. El estado de salud del anciano masculino se asocia a su condición económica, la facilidad de acceso a prestaciones de salud, y a sentimientos de abandono y soledad.

Déficit de vitamina B12 asociado con altas dosis de metformina en adultos mayores diabéticos

OpenAIRE

Hugo Sánchez; Dominique Masferrer; Lydia Lera; Estrella Arancibia; Bárbara Ángel; Cecilia Albala

2014-01-01

Introducción: El objetivo del estudio es estimar si el déficit de B12 se asocia con el uso de la metformina en adultos mayores (AM) diabéticos. Métodos: Estudio de casos y controles en AM diabéticos. Los casos (n = 137) se definieron como AM con B12 221 pmol/L. Se definieron 4 categorías de uso de metformina: no usuarios, ≤ 850 mg/día; > 850 y < 2.550 mg/día; ≥ 2.550 mg/día. Se consideró altas dosis de metformina (≥ 2.550 mg/día). Se cal...

Relationship between the modified star excursion balance test and the 4x10 m shuttle run test in children

Directory of Open Access Journals (Sweden)

Joaquín Calatayud

2017-01-01

Full Text Available Resumen La agilidad y el equilibrio dinámico son habilidades cruciales en la actividad física prepuberal y la participación deportiva, por lo tanto es necesaria la identificación de pruebas eficientes para su evaluación. Evaluar la correlación entre la agilidad y el equilibrio dinámico en niños escolares de primaria. Veintisiete niños y veinte niñas de 10 años participaron voluntariamente en el estudio. El Star Excursion Balance Test (SEBT modificado y el 4x10 m Shuttle Run Test se utilizaron respectivamente para evaluar el equilibrio dinámico y agilidad. Las puntuaciones compuestas del equilibrio dinámico con apoyo diestro mostraron solo entre los niños una moderada correlación significativa (r = -0.51, p < 0.05 con la prueba de agilidad. Sin embargo, entre las niñas se mostró una correlación significativa (r = -0.45, p < 0.05 durante la distancia de alcance posterolateral obtenida en el SEBT. La realización del test completo o de las distancias alcanzadas a nivel posteromedial y posterolateral del SEBT se asocia moderadamente con la agilidad entre los niños, mientras que la distancia posterolateral se asocia con la agilidad entre las niñas.

Envejecimiento saludable: perspectiva de género y de ciclo vital

Directory of Open Access Journals (Sweden)

Mª Pilar Montero-López

2015-04-01

Full Text Available Objetivo: Identificar factores bioculturales y sociales que actúan en diferentes etapas del ciclo vital, implicados en la forma de envejecer de mujeres y hombres mayores de 65 años. Material y Método: 213 personas; edad media 73.9 (std=5.8 en mujeres y 74.8 (std=6.6 en hombres. Datos recogidos en Centros Culturales y de Ocio de la Comunidad de Madrid. El envejecimiento saludable (a partir del número de enfermedades diagnosticadas, percepción de la salud, satisfacción con la vida y estado auditivo y bucal,fue considerado como variable dependiente. La edad, sexo, nivel de estudios, talla sentado, envergadura, edad de primera maternidad y número total de hijos fueron consideradas como variables independientes. Se utilizaron modelos de regresión lineal múltiple para analizar la relación de estas variables con la calidad del envejecimiento. Resultados: El envejecimiento saludable se asocia negativamente con edad y directamente con talla sentado en hombres. En mujeres el envejecimiento saludable se asocia positivamente con años de educación, cuando se incluye la edad de primera maternidad,ésta es la única variable con efecto significativo. Conclusiones: Existen diferentes factores que actúan a lo largo de la vida de los hombres y de las mujeres y que afectan de manera distinta a su forma de envejecer.

Regeneración cardíaca quirúrgica con mioblastos. Experiencia en España

Directory of Open Access Journals (Sweden)

Jesús Herreros

2005-07-01

Conclusiones: La inyección de mioblastos cultivados en suero autólogo asociada a revascularización coronaria es un procedimiento seguro- factible y se asocia a un incremento del índice de viabilidad miocárdica en la región infartada y a una mejoría de la función ventricular izquierda.

ZnSe/ZnSeTe Superlattice Nanotips

Directory of Open Access Journals (Sweden)

Young SJ

2010-01-01

Full Text Available Abstract The authors report the growth of ZnSe/ZnSeTe superlattice nanotips on oxidized Si(100 substrate. It was found the nanotips exhibit mixture of cubic zinc-blende and hexagonal wurtzite structures. It was also found that photoluminescence intensities observed from the ZnSe/ZnSeTe superlattice nanotips were much larger than that observed from the homogeneous ZnSeTe nanotips. Furthermore, it was found that activation energies for the ZnSe/ZnSeTe superlattice nanotips with well widths of 16, 20, and 24 nm were 76, 46, and 19 meV, respectively.

El abandono en las etapas iniciales de los estudios superiores

Directory of Open Access Journals (Sweden)

Norma Zandomeni

2016-01-01

Full Text Available En este artículo se presenta una investigación sobre abandono de los estudios superiores realizada en una universidad argentina. Con un abordaje metodológico cuanti-cualitativo, se analizan datos secundarios y se recupera la perspectiva de distintos actores mediante talleres, encuestas y entrevistas. Se aborda el abandono que se produce en el proceso del ingreso y el generado en los dos primeros años, tanto en su cuantificación como en los factores que operan en el mismo. En el primer caso el abandono se asocia principalmente a factores exógenos a la institución mientras que en el segundo toman fuerza factores internos a la universidad.

Eficacia de la Terapia Psicoeducativa Motivacional Breve Dual (TPMB-D) en pacientes hospitalizados con trastorno por uso de sustancias y patología dual

OpenAIRE

Rubio Perlado, Begoña; Benito, Ana; Juan Porcar, María; Francés, Sonia; Real, Matías; Haro, Gonzalo

2015-01-01

Introducción: El término patología dual (PD) se refiere a la comorbilidad de los trastornos por uso de sustancias (TUS) con trastornos mentales graves. Se asocia con peores resultados de tratamiento que cada uno de estos trastornos por separado, por lo que es importante desarrollar terapias específicas para estos pacientes. En este sentido, el Hospital Provincial de Castellón adaptó la Terapia Psicoeducativa Motivacional Breve (efectiva en pacientes con TUS en Unidad de Desinto...

Nivel de autoestima y factores asociados en adolescentes escolarizados en la parroquia Paccha, Cuenca- Azuay 2015.

OpenAIRE

Zambrano Faicán, Viviana Paola

2017-01-01

Antecedentes: Una autoestima elevada se asocia con bienestar, buen rendimiento académico, entre otras condiciones favorables para el individuo. Sin embargo, en la actualidad aún no están completamente claros los factores que determinan el desarrollo de la autoestima en los individuos. Objetivos: Determinar el nivel de autoestima y su relación con los factores asociados en los adolescentes escolarizados de la parroquia Paccha, Cuenca – Azuay. Materiales y Métodos: Se llevó a cabo un est...

A strategy for human factors/ergonomics: developing the discipline and profession.

Science.gov (United States)

Dul, Jan; Bruder, Ralph; Buckle, Peter; Carayon, Pascale; Falzon, Pierre; Marras, William S; Wilson, John R; van der Doelen, Bas

2012-01-01

Human factors/ergonomics (HFE) has great potential to contribute to the design of all kinds of systems with people (work systems, product/service systems), but faces challenges in the readiness of its market and in the supply of high-quality applications. HFE has a unique combination of three fundamental characteristics: (1) it takes a systems approach (2) it is design driven and (3) it focuses on two closely related outcomes: performance and well-being. In order to contribute to future system design, HFE must demonstrate its value more successfully to the main stakeholders of system design. HFE already has a strong value proposition (mainly well-being) and interactivity with the stakeholder group of 'system actors' (employees and product/service users). However, the value proposition (mainly performance) and relationships with the stakeholder groups of 'system experts' (experts fromtechnical and social sciences involved in system design), and 'system decision makers' (managers and other decision makers involved in system design, purchase, implementation and use), who have a strong power to influence system design, need to be developed. Therefore, the first main strategic direction is to strengthen the demand for high-quality HFE by increasing awareness among powerful stakeholders of the value of high-quality HFE by communicating with stakeholders, by building partnerships and by educating stakeholders. The second main strategic direction is to strengthen the application of high-quality HFE by promoting the education of HFE specialists, by ensuring high-quality standards of HFE applications and HFE specialists, and by promoting HFE research excellence at universities and other organisations. This strategy requires cooperation between the HFE community at large, consisting of the International Ergonomics Association (IEA), local (national and regional) HFE societies, and HFE specialists. We propose a joint world-wide HFE development plan, in which the IEA takes a

Deficiencia de vitamina D en la edad pediátrica. Una oportunidad de prevención

OpenAIRE

López-González, Desirée; Méndez-Sánchez, Lucía; Guagnelli, Miguel Ángel; Clark, Patricia

2015-01-01

La prevalencia de deficiencia de vitamina D en la población pediátrica ha incrementado en los últimos años y se considera que continúa subdiagnosticada y subtratada. De acuerdo con datos de la Encuesta Nacional de Salud y Nutrición 2006, en México se ha estimado una prevalencia del 16% en niños de 2 a 12 años. La vitamina D desempeña un papel fundamental en la formación y homeostasis del hueso, y consecuentemente en el crecimiento. Su deficiencia se asocia con enfermedades como raquitismo y o...

Relación entre nivel de glicemia y morbimortalidad en el paciente pediátrico crítico

OpenAIRE

Tangari, Elsa; Talasimov, Carolina; Cabaleiro, Mariela; Alberti, Marta

2009-01-01

El niño en situación crítica presenta en forma frecuente hiperglicemia vinculada al estrés y se asocia a mayor morbimortalidad en diversas publicaciones. Objetivo: determinar la prevalencia de hiperglicemia en el niño crítico y el nivel de hiperglicemia que se vincula con incremento en la morbimortalidad. Material y método: se estudiaron 96 pacientes de 1 mes a 14 años, que ingresaron en la Unidad Cuidados Intensivos de niños(UCIN) en situación crítica (requieren asistencia respiratoria mecán...

Diferencias en el juego simbólico desarrollado en el aula de psicomotricidad entre niños y niñas.

OpenAIRE

Iruretagoyena, Oihana

2012-01-01

Este estudio analizó las diferencias del juego simbólico desarrollado por niños y niñas en las sesiones de psicomotricidad. Se desarrolló una investigación etnográfica en la ikastola Langile mediante el cual se triangularon datos obtenidos mediante la observación y entrevistas a diferentes profesoras. La muestra observada la conformaron 24 niños/as de 4 años. Los resultados muestran diferencias entre el juego de los niños y de las niñas respecto al rol (se asocia casi siempre al género, repre...

Hipertensión arterial en diferentes edades de la mujer

OpenAIRE

José Pacheco-Romero

2010-01-01

La hipertensión se asocia a comorbilidades, como la diabetes mellitus, enfermedad coronaria, apoplejía, enfermedad vascular periférica, falla renal crónica, todo lo cual disminuye la expectativa de vida. La población peruana no se escapa de presentar esta enfermedad de manera similar al resto del mundo, por lo que la hipertensión debe ser debe ser detectada a tiempo en la atención médica diaria, para un manejo oportuno y de beneficio en años de vida con calidad. Se describe la ocurrencia de h...

Protección jurídica del nasciturus

OpenAIRE

Ramírez Jaspeado, Belén

2016-01-01

A continuación, se presentan las conclusiones a las que se llegó con la presente investigación; con la finalidad de mejorar la situación actual del problema estudiado en esta tesis. 1. El inicio de la vida se asocia con mayor apego a la teoría de la concepción en virtud de que a partir de este instante comienza un proceso de desarrollo continuo e independiente que de no existir alteración alguna conducirá inevitablemente a la formación de un individuo genéticamente nuevo. Nuestro Código Ci...

Experiencia con ibuprofeno para el tratamiento de la persistencia de conducto arterioso en un hospital de tercer nivel en la Ciudad de México

Directory of Open Access Journals (Sweden)

G. Cordero-González

2016-07-01

Conclusiones: No se encontró diferencia en el éxito para el primer o segundo ciclo (47.7 vs. 42.8% (p = 1. Con las dosis de ibuprofeno actualmente utilizadas, el porcentaje de éxito en un segundo ciclo es menor pero no significativo. No encontramos diferencias en cuanto al porcentaje de éxito que se relacionen con los líquidos administrados, la presencia de sepsis, el uso de ventilación mecánica y/o furosemida, y tampoco el inicio posterior al quinto día de vida se asocia a incremento en el porcentaje de fracaso.

Monitorización ambulatoria de la presión arterial en niños con obesidad

OpenAIRE

García-Vao Bel, Carlos María

2015-01-01

Tesis Doctoral leída en la Universidad Rey Juan Carlos de Madrid en 2015. Directores de la Tesis: Ángel Gil de Miguel y María José Rivero Martín Se define la obesidad como un exceso de masa grasa con relación a la masa corporal total, esta acumulación de grasa es excesiva y generalizada tanto en el tejido subcutáneo como en el resto de los tejidos y se asocia a un desequilibrio en las proporciones de los componentes magro o muscular, óseo, visceral y adiposo. Por tanto no se pu...

El culto de Maximón en Guatemala

OpenAIRE

Pédron‑Colombani, Sylvie

2009-01-01

Este artículo se enfoca en la figura de Maximón, deidad sincrética de Guatemala, en un contexto de desplazamiento de la religión católica popular por parte de las iglesias protestantes. Esta divinidad híbrida a la cual se agregan santos católicos como Judas Iscariote o el dios maya Mam, permite la apropiación de Maximón por segmentos diferenciados de la población (tanto indígena como mestiza). Permite igualmente ser símbolo de protestas sociales enmascaradas cuando se asocia Maximón con figur...

Avances en la química de coordinación de los tetrilenos pesados

OpenAIRE

Polo Coca, Diego

2015-01-01

Esta tesis doctoral se enmarca en el campo de la Química Inorgánica y, más concretamente, en el de la química que asocia los metales de transición (Ms) con los parientes más pesados de los carbenos, conocidos comúnmente como tetrilenos pesados (TPs) o metalilenos. Su formato es el de ¿Compendio de Publicaciones¿ y contiene los 10 artículos científicos que hasta ahora se han publicado sobre su contenido. En la primera parte de la memoria se describen reacciones de tetrilenos pesados acícli...

Mastocitosis sistémica: repercusión ósea

OpenAIRE

Francisco R. Spivacow; Marcelo Sarli; Rosana Nakutny

2012-01-01

La mastocitosis sistémica es una enfermedad caracterizada por acumulación de mastocitos en varios órganos, de los cuales el más afectado es la piel. La repercusión ósea de esta enfermedad es poco frecuente y en general se la asocia al desarrollo de osteoporosis secundaria con o sin fracturas óseas. Se presentan tres pacientes con lesiones características en piel de mastocitosis y diferentes manifestaciones óseas; el primer caso es una mujer de 51 años en la que se observó una variante esclero...

Human factors verification and validation of the advanced nuclear plant control room design

International Nuclear Information System (INIS)

Gutierrez, Richard; Zizzo, David; Yu, Kim

2005-01-01

The GE Advanced Boiling Water Reactor (ABWR) design has implemented the applicable human factors engineering (HFE) principles in the design of human-system interfaces (HSI). The ABWR uses unique features such as large mimic and touch-screen technology to present plant overviews and system operating details to the control room operating staff. The HSI designs, both in the console panels and the software generated graphical user interfaces, have been developed and evaluated using HFE guidelines. In addition to HFE guidelines reviews performed during design and implementation, broader reviews have been performed under the HFE Verification and Validation Implementation Plan (HFE V and VIP). Based upon the NUREG-0711, Nuclear Regulatory Commission (NRC) HFE Program Review Model (HFE PRM) (Reference 1), the HFE V and VIP, hereafter also referred to as V and V, has provided feedback during the various phases of design, implementation, and integration of the HSI. As one of the ten elements of the HFE PRM, the V and V activities reaffirm that the design of the HSI conforms to the HFE design principles and that the plant operating staff in the control room can perform their assigned tasks. This rigorous HFE V and V process is now being applied in the implementation of the ABWR design for Taiwan Power Company's Lungmen Power Station. Two 1350 MWe ABWR units are currently under construction at Lungmen. The HFE V and V ensures that the process for the design is compliant with the HFE principles. An important aspect of the Lungmen HFE program has been the direct involvement of the end user, Taiwan Power Company (TPC), throughout the design development and implementation. These HFE V and V activities, performed in three phases, ensures that the necessary displays, control, and alarms are provided to support the identified personnel tasks. The HFE V and V also checks to determine that the design of each identified component is compliant with the HFE principles. The V and V ensures

Un Modelo de Programación No-lineal para la Planeación de la Producción de Gas y Petróleo A Non-Linear Programming Model for the Gas and Oil Production Planning

OpenAIRE

Oswaldo Robles-Agudo; Richart Vázquez-Román

2008-01-01

En este trabajo se propone un modelo matemático que permite optimizar la planeación de la producción de gas y petróleo de varios pozos. El horizonte de planeación se divide en varios períodos de tiempo en los cuales se tiene una demanda conocida y se asocia un coeficiente de costo a cada pozo en la función objetivo. La formulación contempla la disminución de la presión en la boca del pozo debido a la extracción y la recuperación de la presión cuando la producción del mismo se anula. Además, s...

HFE Mutations C282Y and H63D in Iranian Population With Type 2 Diabetes

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Golchin

2015-04-01

Full Text Available Background Type 2 diabetes (T2D is a common metabolic disease caused by insulin secretion defects, which is associated with a variety of complications such as retinopathy, nephropathy, and neuropathy. Objectives Regarding the relationship between type 2 diabetes and hereditary chromatists, we conducted a genetic analysis on two previously reported mutations C282Y and H63D related to the HFE gene in our population. Patients and Methods Altogether, 145 patients with type 2 diabetes and 145 healthy controls were examined. A genotyping assay performed using electrophoresis of the DNA digestion products from MboI and RsaI for H63D and C282Y, respectively. Results Results showed a significant difference between case and controls regarding C282Y (P value < 0.001 and H63D genotypes (P value = 0.013. We also found a relationship between both mutations and nephropathy. Moreover, the difference between C282Y genotypes of patients with retinopathy and healthy controls were statistically significant (P value = 0.020 while there was no association between H63D and retinopathy. In addition, observed differences of both mutations were significant when nephropathic patients compared to the controls. Conclusions Our study showed a significant association between H63D and C282Y mutations and the risk of type 2 diabetes in Iranian population.

Comparación entre bioimpedancia espectroscópica y fórmula de Watson para medición de volumen corporal en pacientes en diálisis peritoneal

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Gonzalo Martínez Fernández

2016-01-01

Conclusiones: Existen diferencias en el V de los pacientes de una unidad de DP según sea calculado por fórmula de Watson o por BIS. La presencia de hipertensión, diabetes, hipoalbuminemia, obesidad, malnutrición, inflamación, E/I ratio ≥1 y la ausencia de diuresis residual se asocia con la aparición de estas diferencias.

Efecto de una dieta rica en proteínas y alta en fibra más la suplementación con aminoácidos de cadena ramificada sobre el estado nutricional de pacientes con cirrosis

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A. Ruiz-Margáin

2018-01-01

Conclusión: La suplementación con AACR más una dieta alta en proteína y fibra es una intervención segura en los pacientes con cirrosis. Ayuda al incremento de la masa muscular y no eleva los niveles de amonio o de glucosa, y tampoco se asocia con el desarrollo de encefalopatía hepática.

Absceso del psoas tuberculoso, debut en paciente inmunodeprimido:

OpenAIRE

Nicolás Drolett SF.; Nicolás Drolett SF.; Nakita Reyes J.; Dr. Marcelo Zamorano D.

2014-01-01

RESUMEN INTRODUCCIÓN: El absceso del psoas (AP) es una patología infrecuente de difícil diagnóstico. Se clasifica en primario o secundario teniendo como factor de riesgo común la inmunodeficiencia. PRESENTACIÓN DEL CASO: Paciente masculino de 40 años sin antecedentes mórbidos. Consulta por cuadro de un mes de evolución caracterizado por dolor lumbar derecho que aumenta al flexionar el muslo ipsilateral. Se asocia compromiso del estado general, dolor abdominal, sensació...

Trastorno por déficit de atención e hiperactividad /

OpenAIRE

Achabal Iturregui, Garazi

2013-01-01

La detección precoz y la intervención temprana son dos claves fundamentales en el campo del Trastorno por Déficit de Atención e Hiperactividad. No obstante, hemos de tener presente para crearnos una visión global del trastorno, que tal como apuntan algunos autores, existe preocupación en cuanto al exceso de diagnostico y tratamiento que se pueda estar produciendo en torno al ese trastorno. Por otro lado, en ocasiones, el TDAH se asocia con otros trastornos (trast...

TIEMPO DE OCIO Y PRÁCTICA FÍSICO-DEPORTIVA EN ESCOLARES (10 - 12 AÑOS DE LA REGIÓN DE MURCIA (ESPAÑA: DIFERENCIAS EN FUNCIÓN DEL GÉNERO

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ELISEO GARCÍA CANTÓ

2012-01-01

aplicado en recientes investigaciones. Los resultados obtenidos nos indican que dos tercios de los escolares (79,4% afirman realizar ejercicio físico o deporte fuera del horario lectivo, existiendo una considerable proporción de ocupación activa del tiempo libre que se asocia significativamente al sexo masculino. El análisis de la covarianza efectuado señala la existencia de diferencias significativas a favor de los varones en el nivel de actividad física habitual durante el tiempo de ocio.

Estudio del efecto de enoxaparina sobre la cirrosis e hipertensión portal experimental

OpenAIRE

Fortea Ormaechea, José Ignacio

2016-01-01

La administración de anticoagulantes en pacientes con cirrosis hepática es controvertida debido a que esta enfermedad ha sido considerada durante mucho tiempo un estado hipocoagulante. Sin embargo, en las últimas dos décadas se ha puesto de manifiesto que la hemostasia mantiene un equilibrio precario en pacientes con cirrosis hepática, pudiendo presentar tanto un fenotipo hipocoagulante como uno protrombótico, y que la anticoagulación en pacientes con cirrosis hepática no se asocia a un mayor...

¿Quién es la víctima y quién el agresor en la violencia física entre parejas?: estudio epidemiológico en siete ciudades del Perú Who is the victim and who the offender in intimate partner physical violence?: an epidemiological study in seven cities of Peru

OpenAIRE

Fabián Fiestas; Ruth Rojas; Alfonso Gushiken; Ernesto Gozzer

2012-01-01

Objetivos. Identificar factores asociados con la probabilidad de ser víctima o agresor en violencia física entre parejas. Materiales y métodos. Se analizó la base de datos de una encuesta poblacional aplicada en siete ciudades de Perú (Lima, Arequipa, Huamanga, Trujillo, Cusco, Callao y Maynas). Participaron 6399 hombres y mujeres, de los cuales 3909 refirieron vivir en pareja al momento de la entrevista. Se empleó regresión logística univariada y multivariada para identificar factores asocia...

Análisis de la precipitación en la llanura chaqueña argentina y su relación con el comportamiento de la circulación atmosférica y las temperaturas de la superficie del mar Rainfall analysis in chaco plains and its relationship with atmospheric circulation behavior and sea surface temperatures

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Marcela Hebe González

2010-12-01

Full Text Available El objetivo del presente estudio es detectar indicadores de circulación que se relacionen con la variabilidad interanual de la lluvia en la llanura chaquena. La precipitación media en regiones definidas se correlacionó con la temperatura de la superficie del mar, altura geopotencial en 1000, 500 y 200 Hpa, presión a nivel del mar, humedad específica en 925Hpa, viento zonal y meridional en 850 Hpa, simultáneamente y en el mes previo. El aumento de la precipitación estival se asocia al debilitamiento del anticiclón del Atlántico y altos valores de humedad específica en el noreste de Argentina. En la región noreste además se asocia a viento este y debilitamiento del viento del norte mientras que la región noroeste es la más influenciada por La Nina. En primavera el rasgo fundamental es la relación en el noreste con la fase cálida del ENOS. El rasgo más importante es que se asocia la precipitación estival en las tres subregiones con el debilitamiento del anticiclón del Atlántico durante el mes previo mientras que en la primavera la senal más importante se relaciona con el ENOS.The aim of this study is to detect atmospheric signals related to the interannual variability of rainfall in the Chaco Plains. Mean rainfall series in regions defined, are correlated to sea surface temperature, 200, 500, and 1000Hpa geopotential height, sea level pressure, 925 Hpa specific humidity and 850Hpa wind fields in the simultaneous three month period and in the previous month. The increase of summer precipitation is associated to the weakening of the Atlantic High and high values of low level specific humidity in northeast Argentina. In the northeast region it is also associated with easterlies winds and weak northerly and the northwest region is influenced by La Nina. In spring, the principal feature is the relation with the warm phase of ENOS phenomenon. The most important feature is that summer rainfall in the three subregions, is associated

Absorption of manganese and iron in a mouse model of hemochromatosis.

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Jonghan Kim

Full Text Available Hereditary hemochromatosis, an iron overload disease associated with excessive intestinal iron absorption, is commonly caused by loss of HFE gene function. Both iron and manganese absorption are regulated by iron status, but the relationships between the transport pathways of these metals and how they are affected by HFE-associated hemochromatosis remain poorly understood. Loss of HFE function is known to alter the intestinal expression of DMT1 (divalent metal transporter-1 and Fpn (ferroportin, transporters that have been implicated in absorption of both iron and manganese. Although the influence of HFE deficiency on dietary iron absorption has been characterized, potential effects on manganese metabolism have yet to be explored. To investigate the role of HFE in manganese absorption, we characterized the uptake and distribution of the metal in Hfe (-/- knockout mice after intravenous, intragastric, and intranasal administration of (54Mn. These values were compared to intravenous and intragastric administration of (59Fe. Intestinal absorption of (59Fe was increased and clearance of injected (59Fe was also increased in Hfe(-/- mice compared to controls. Hfe (-/- mice displayed greater intestinal absorption of (54Mn compared to wild-type Hfe(+/+ control mice. After intravenous injection, the distribution of (59Fe to heart and liver was greater in Hfe (-/- mice but no remarkable differences were observed for (54Mn. Although olfactory absorption of (54Mn into blood was unchanged in Hfe (-/- mice, higher levels of intranasally-instilled (54Mn were associated with Hfe(-/- brain compared to controls. These results show that manganese transport and metabolism can be modified by HFE deficiency.

Interaction of Se and GaSe with Si(111)

International Nuclear Information System (INIS)

Meng, Shuang; Schroeder, B. R.; Olmstead, Marjorie A.

2000-01-01

Deposition of Se and GaSe on Si(111)7x7 surfaces was studied with low-energy electron diffraction, x-ray photoelectron spectroscopy, and x-ray photoelectron diffraction to probe initial nucleation and interface structure for GaSe/Si(111) heteroepitaxy. Room-temperature deposition of Se on Si(111)7x7 results in an amorphous film. Subsequent annealing leads to Se evaporation without ordering or interdiffusion. Se deposition at 450 degree sign C saturates at submonolayer coverage with no diffusion of Se into the substrate. There is no clear evidence of ordered sites for the Se. Growth of GaSe on Si(111)7x7 above 500 degree sign C results in a pseudomorphic bilayer, with Si-Ga-Se bonding. Additional GaSe does not stick to the bilayer above 525 degree sign C. The resulting Se lone pair at the surface leads to an ideally passivated surface similar to As/Si(111). This stable surface is similar to the layer termination in bulk GaSe. The single domain bilayer is oriented with the Ga-Se bond parallel to the substrate Si-Si bond. (c) 2000 The American Physical Society

Anticoncepción en adolescentes mexicanos de escuelas del nivel medio superior: uso y necesidades insatisfechas

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Aremis Villalobos

2017-08-01

Full Text Available Objetivo. Describir el comportamiento sexual y el uso de anticonceptivos en adolescentes escolarizados. Material y métodos. Encuesta representativa nacional en escuelas de educación media superior en México, realizada en 2014. Modelos logísticos identifican factores asociados al uso de anticonceptivos y a necesidades insatisfechas de anticoncepción (NIA. Resultados. Entre los hombres, no emplear anticonceptivos en la última relación sexual se asocia con la no utilización de éstos durante el debut sexual (RM=11.5;IC95% 5.6-23.4 y desconocer anticonceptivos efectivos (RM=2.4; IC95% 1.04-5.5. Entre las mujeres, no emplear anticonceptivos se asocia con el no uso de éstos durante el debut sexual (RM=4.5; IC95% 2.3-8.4 y la falta de autoeficacia en el uso/negociación del condón (RM=3.1; IC95% 1.18.2. Las NIA se asocian con baja autoeficacia respecto al uso/negociación del condón (RM=3.5; IC95% 1.3-9.4, no usar anticonceptivos en el debut sexual (RM=9.0; IC95% 2.5-32.4 y usar alcohol o drogas en relaciones sexuales (RM=3.0;IC95% 1.1-8.1. Conclusiones. Se requieren estrategias que garanticen el uso de anticonceptivos desde el debut sexual y que promuevan la autoeficacia y las prácticas seguras entre los adolescentes

Nutritional intake and weight z-scores in very low birth weight infants in Peru

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Alvaro Proaño

2016-03-01

Full Text Available OBJETIVOS Determinar las ingestas nutricionales en los recién nacidos de muy bajo peso al nacer y su respectivo crecimiento en el primer mes de vida. Adicionalmente, identificar factores para un desenlace negativo en el periodo neonatal de esta población. METODOS Estudio de serie de casos desarrollado en un hospital de tercer nivel en Lima, Perú desde 2011 a 2012. La información se obtuvo de las historias médicas. No se utilizó un protocolo de nutrición durante el estudio. La ingesta diaria del volumen, la energía y las proteínas fue registrada al igual que el puntaje z del peso de manera semanal. Se utilizó regresión logística para identificar factores asociados a un desenlace adverso, que se define como mortalidad neonatal o restricción de crecimiento extrauterino en los primeros 28 días de vida. RESULTADOS Luego del criterio de selección, se incluyeron a 76 participantes. Las ingestas nutricionales fueron similares a los valores descritos en la literatura, pero la ingesta proteica fue sub óptima durante las cuatro semanas. El puntaje z del peso al nacer se asocia con un desenlace adverso (p=0,035. Se determinó que un puntaje z menor de 1,09 predice un desenlace negativo con un área bajo la curva ROC de 96,8% (93,5%, 100%, con un intervalo de confianza del 95%. CONCLUSIÓN Las ingestas proteicas fueron sumamente deficientes en este estudio. Sin embargo, un desenlace adverso se asocia más a un pobre puntaje z al nacer que a factores relacionados a la nutrición.

Canales espaciales de articulación en el corredor turístico Los Cabos, Baja California Sur, México

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Álvaro López-López

2002-01-01

Full Text Available El corredor de Los Cabos es uno de los espacios turísticos más dinámicos de México que, en su articulación territorial, ha generado canales que muestran una situación contrastante: las ligas que se mantienen hacia la costa occidental de Estados Unidos y, dentro del corredor, las relacionadas con los espacios turísticos, son altamente eficientes; en contraste, la red de infraestructura, transportes y comunicaciones interna que se asocia con la población local y regional, presenta aún serias deficiencias.

Efecto del entrenamiento físico sobre los factores endoteliales en el sistema arterial de conejo

OpenAIRE

Marchio, Patricia

2015-01-01

Las enfermedades cardiovasculares constituyen una de las primeras causas de mortalidad en la población occidental y prácticamente el 50% se podrían prevenir con modificaciones del estilo de vida. En este sentido, la práctica regular de ejercicio físico se asocia con una reducción de entre un 20 a un 40% de la incidencia de eventos vasculares primarios y secundarios y del riesgo de muerte por enfermedad cardiovascular. Parte de estos beneficios estarían relacionados con los efectos directos y ...

Factores de Riesgo Odontológico en pacientes médicamente comprometidos registrados en un Centro de Atención Primaria de Odontología del Servicio Galego de Saúde – SERGAS

OpenAIRE

Iglesias Corchero, Ana María

2014-01-01

En la actualidad, ha aumentado exponencialmente la posibilidad de que un Odontólogo se enfrente a una emergencia médica. Esto es debido al aumento en la atención de pacientes con enfermedades crónicas (diabetes e hipertensión), con cardiopatías, inmunodeprimidos, trasplantados, edad avanzada. También existen otros factores como los tratamientos dentales más complejos y la utilización de fármacos. La Odontología es una especialidad que se asocia con ansiedad, temor y angustia en el paciente y ...

Impacto de la cirugía bariátrica en la calidad de vida y en la calidad de alimentación

OpenAIRE

Safar, María Nahime

2012-01-01

La obesidad mórbida es una enfermedad crónica resultante de una compleja interacción entre factores genéticos y medioambientales, que se caracteriza por el exceso de grasa corporal progresiva. Se asocia a un mayor riesgo de mortalidad sobre todo de origen cardiovascular, así como a una serie de comorbilidades, además de una gran afectación psicológica que disminuye la calidad y la esperanza de vida de los pacientes que la padecen. La cirugía de la obesidad mórbida o cirug...

Un modelo de recuperación de información basado en SVMs

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M. Fernanda Maldonado

2004-01-01

Full Text Available Los clasificadores como los SVMs (Support Vector Machines se usaron para la clasificación de documentos de manera muy eficiente, pero su utilidad no ha sido comprobada para la recuperación de información (RI en el momento de jerarquerizar los documentos. En este artículo proponemos una transformación que asocia el proceso de la RI a un nuevo espacio vectorial en el que un clasificador basado en SVMs se entrena para aprender el concepto de similitud frente a los documentos.

Prevalencia del déficit de vitamina B12 en mayores de 60 años hospitalizados. Estudio del polimorfismo C677T de la enzima 5-10 MTHFR en pacientes con déficit de vitamina B12

OpenAIRE

Alonso Ortiz, María Belén

2014-01-01

Programa de doctorado: Avances en Medicina Interna. [ES] El déficit de Vitamina B12 es frecuente en los pacientes mayores. Sin embargo, son escasos los trabajos realizados en el ámbito hospitalario. Este déficit se asocia frecuentemente con elevación de la homocisteína plasmática, conocido factor de riesgo cardiovascular. Además la mutación C677T del gen de la enzima MTHFR se relaciona con hiperhomocistenemia, que puede coexistir con déficit de Vitamina B12, cuya frecuencia y consecuencias...

Destrucción costal: una rara forma de presentación de la nocardiosis pulmonar

OpenAIRE

Julve Pardo, R.; Carrión Valero, F.; Gonzalvo Bellver, F.; Prat Fornells, J.; Pascual Izuel, J. M.

2001-01-01

Clásicamente, la infección por Nocardia spp. se asocia a estados de depresión inmunológica, procesos neoplásicos y tratamientos prolongados con inmunosupresores y glucocorticoides. La afectación pulmonar es la más característica, siendo infrecuente la diseminación del proceso por extensión local a la pared costal y el tejido celular subcutáneo. Presentamos un caso de nocardiosis pulmonar por Nocardia asteroides en una paciente diabética sin otros factores de riesgo conocidos, que se manifestó...

Evolución geológica del margen Norte de la Placa del Caribe, República Dominicana

OpenAIRE

Pérez-Estaun, Andrés; Tavares, I.; García-Cortés, Ángel; Hernaiz Huerta, P. P.

2002-01-01

La Isla La Española se encuentra situada en la actualidad en la parte septentrional de la Placa del Caribe. Conjuntamente con Puerto Rico, constituye una unidad que puede interpretarse como una microplaca, limitada al Norte por una zona de subducción oblicua, con una fuerte componente de salto en dirección, y al Sur por otra zona de subducción incipiente a la que se asocia la Fosa de los Muertos. El margen Norte de la Placa del Caribe ha evolucionado desde constituir un límite contro...

Alopecia frontal fibrosante: una enfermedad en auge

OpenAIRE

Quintana-Sancho, A. de; Piris-García, X.; Valle-García, N.; Hierro-Cámara, M.

2016-01-01

La alopecia frontal fibrosante (AFF) es un tipo de alopecia cicatricial cuya incidencia está aumentando de forma significativa en nuestro país. Se caracteriza por un retroceso en la línea de implantación del pelo a nivel frontotemporal que afecta mayoritariamente a mujeres postmenopaúsicas, con un impacto negativo en su calidad de vida. Se asocia a menopausia precoz en un 14% de los casos y a hipotiroidismo en un 15%. Con respecto al tratamiento, son los inhibidores de la 5alfa-reductasa, los...

Preso y drogodependiente: doble estigma

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Rafael Clua García

2010-12-01

Full Text Available Fornons Fontdevila, David (2009. Prisión y drogas: doble condena. Barcelona: deParís. David Fornons Fontdevila, tras varios años de trabajo en diferentes ámbitos del Centro Penitenciario de Hombres de Barcelona, La Modelo, ha realizado esta etnografía sobre las personas drogodependientes privadas de libertad. Ha conseguido desnudar su situación, abriéndonos las puertas de una institución de la que poco se habla y mucho menos cuando se asocia a los consumidores de drogas.

Patrones de infiltración leucocitaria y de expresión tisular de quimioquinas, factor de crecimiento endotelial vascular y mediadores del metabolismo oxidativo en lesiones inflamatorias y neoplásicas de cervix

OpenAIRE

Carrero Castillo, Yenddy Nayghit

2012-01-01

En nuestro trabajo de investigación sobre el patrón de infiltración leucocitaria de epitelio y estroma uterino y de la expresión tisular de quimioquinas, factor de crecimiento endotelial vascular y metabolitos oxidativos en pacientes con displasia epitelial, con cervicitis sin alteración displásica y controles sanos se concluye que: La progresión en el grado de displasia epitelial se asocia a una mayor y selectiva infiltración de linfocitos sin modificaciones en la estirpe monicitaria y la re...

Efecto de la obesidad abdominal, la resistencia a la insulina y la leptina intrafolicular en la fecundación "in vitro"

OpenAIRE

Llaneza Suárez, David

2014-01-01

La relación existente entre el balance energético y la fertilidad se conoce desde hace tiempo y puede asociarse a infertilidad y peores tasas de respuesta en pacientes que están realizando ciclos de Fecundación In Vitro (FIV/ICSI). La obesidad abdominal se asocia frecuentemente con un estado inflamatorio, con Resistencia a la Insulina (RI) y con niveles elevados de leptina La relación de estos cambios con los resultados de los ciclos FIV/ICSI aun no es conocido del todo. HIPÓTESIS El...

Affective and Cognitive Aspects in Fibromyalgia: The Roles of Catastrophizing and Acceptance

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Rodero Fernández, Baltasar; García Campayo, Javier; Gascón Santos, Santiago

2012-01-01

La fibromialgia es una enfermedad crónica, de causa actualmente desconocida, que se caracteriza por la presencia de dolor músculo-esquelético generalizado, asociado a una serie de puntos dolorosos específicos que nos ayudan a su diagnóstico (Wolfe et al., 1990). Con frecuencia se asocia con fatiga crónica, alteraciones del sueño, rigidez matutina, alteraciones del estado de ánimo (ansiedad y depresión), cefaleas, problemas en la menstruación, dolor temporomandibular y síndrome del intestino i...

Canales espaciales de articulación en el corredor turístico Los Cabos, Baja California Sur, México

OpenAIRE

Álvaro López-López; Álvaro Sánchez-Crispín

2002-01-01

El corredor de Los Cabos es uno de los espacios turísticos más dinámicos de México que, en su articulación territorial, ha generado canales que muestran una situación contrastante: las ligas que se mantienen hacia la costa occidental de Estados Unidos y, dentro del corredor, las relacionadas con los espacios turísticos, son altamente eficientes; en contraste, la red de infraestructura, transportes y comunicaciones interna que se asocia con la población local y regional, present...

Kinesioterapia respiratoria en la cirugía cardíaca pediátrica

OpenAIRE

Antunez, Rodrigo

2013-01-01

Un gran número de pacientes portadores de cardiopatías congénitas requiere tratamiento quirúrgico, este se asocia al desarrollo de complicaciones respiratorias en el periodo post-operatorio, se definen como cualquier anomalía que afecta la función pulmonar y prolongan la estadía del paciente en la UCIP, las más frecuentes son la atelectasia y la neumonía. Objetivos: Evaluar la influencia de la kinesioterapia respiratoria en el post-operatorio de cirugía cardiaca en pacientes pediátricos. ...

Estrés psicosocial y baja resiliencia, un factor de riesgo de hipertensión arterial

OpenAIRE

Costa de Robert, Sara; Barontini, Marta; Forcada, Pedro; Carrizo, Patricia; Almada, Lucas

2010-01-01

Introducción El estrés psicosocial crónico (EPC) fue propuesto como un factor de riesgo cardiovascular (FRC); sin embargo, la complejidad y la falta de medidas objetivas para evaluarlo, unidas al hecho de que no todas las personas reaccionan ante él de igual manera, determinaron que en la actualidad no se cuente con estudios concluyentes al respecto. Objetivos Determinar si la baja resiliencia (BR) frente al EPC se asocia con hipertensión arterial y daño de órgano blanco en pacientes ambulato...

Estrés psicosocial y baja resiliencia, un factor de riesgo de hipertensión arterial

OpenAIRE

Lucas Almada; Patricia Carrizo; Pedro Forcada; Marta Barontini; Sara Costa De Robert

2010-01-01

IntroducciónEl estrés psicosocial crónico (EPC) fue propuesto como un factor de riesgo cardiovascular (FRC); sin embargo, la complejidad y la falta de medidas objetivas para evaluarlo, unidas al hecho de que no todas las personas reaccionan ante él de igual manera, determinaron que en la actualidad no se cuente con estudios concluyentes al respecto.ObjetivosDeterminar si la baja resiliencia (BR) frente al EPC se asocia con hipertensión arterial y daño de órgano blanco en pacientes ambulatorio...

Desarrollo óseo y actividad física: papel mediador de la masa magra, masa grasa y condición física

OpenAIRE

Torres Costoso, Ana Isabel

2016-01-01

La osteoporosis es el trastorno clínico que más comúnmente afecta al metabolismo óseo. Se caracteriza por unos niveles bajos de baja masa ósea y un deterioro de la arquitectura del tejido óseo que traen como consecuencia un incremento de la fragilidad ósea y un incremento del riesgo de fracturas. Aunque la osteoporosis se asocia a la edad avanzada, un desarrollo óseo apropiado desde edades tempranas ayuda a prevenir esta patología. De hecho, incrementos en la consistencia ósea durante la infa...

Efectos centrales y periféricos de la administración crónica del agonista cannabinoide win 55,212-2, y su utilización en algunas alteraciones producidas por el cisplatino en rata

OpenAIRE

Cabezos Rodríguez, Pablo Antonio

2010-01-01

Tesis Doctoral leída en la Universidad Rey Juan Carlos de Madrid en 2010. Directora de la Tesis: Raquel Abalo Delgado Los cannabinoides ejercen un amplio espectro de acción sobre la actividad fisiológica normal. Por sus efectos agudos en la esfera cognitiva y psicológica, los derivados de la planta Cannabis sativa se han usado como droga de uso recreacional durante más de 4000 años. Pero la administración de compuestos cannabinoides se asocia, además, con la producción de efect...

Migración y diferenciación étnica en Guatemala. Ser indígena en un contexto de globalización

OpenAIRE

Santiago Bastos

1999-01-01

En este artículo se discute si el concepto de la desterritorialización de las identidades, que se asocia a la globalización, es útil para describir la nueva relación que mantienen las poblaciones indígenas de Latinoamérica con el espacio, como efecto del proceso de dispersión que viven desde hace unas décadas. La comparación del proceso migratorio entre hogares indígenas y no indígenas que residen en tres espacios populares de la ciudad de Guatemala muestra al...

Almudena Moreno Mínguez, Antonio López Peláez y Sagrario Segado Sánchez-Cabezudo, La transición de los jóvenes a la vida adulta. Crisis económica y emancipación tardía, Editorial Obra Social “La Caixa”,

OpenAIRE

Hernández Prados, María de los Ángeles

2017-01-01

La transacción de los jóvenes a la vida adulta es un acto cada vez más complejo, diversificado y sujeto a las incertidumbres propias de sociedades altamente dinámicas y cambiantes. El cambio social acelerado resultante de los procesos de individualización y la desestandarización ha transformado el significado de las transiciones juveniles. Por transición se entiende ese espacio imaginario que se asocia al cruzar la frontera entre una etapa del desarrollo humano asociada a la interdependencia ...

Estrategias de afrontamiento e inadaptación en niños y adolescentes

Directory of Open Access Journals (Sweden)

Francisco M. Morales

2010-12-01

Full Text Available El objetivo general del presente trabajo es estudiar la relación entre el empleo de estrategias de afrontamiento, ajuste psicológico y manifestación de comportamientos desadaptados. El enfoque adoptado es situacional, considerando la estrategia en relación con la situación particular, en concreto, se han evaluado las estrategias de afrontamiento del estrés utilizadas por escolares andaluces de educación primaria en relación con cuatro tipos de estresores: escolar, familiar, relaciones con los iguales y salud. Participaron 402 niños entre 9 y 12 años. Los instrumentos utilizados fueron: el IIEC (Inventario Infantil de Estresores Cotidianos, el ESAN (Estrategias situacionales de afrontamiento en niños y en niñas y el BASC (Sistema de Evaluación de la conducta en niños y adolescentes. Los resultados demuestran un uso diferencial de estrategias de afrontamiento según el problema o situación planteada. El análisis de las estrategias de afrontamiento revela además que el empleo de estrategias de afrontamiento de aproximación a los problemas se asocia a un mayor grado de ajuste y adaptación mientras que un mayor empleo de estrategias de tipo evitativo se asocia con menos ajuste y comportamientos más desadaptativos.

Best practice guidelines for the molecular genetic diagnosis of Type 1 (HFE-related hereditary haemochromatosis

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Barton David E

2006-11-01

Full Text Available Abstract Background Hereditary haemochromatosis (HH is a recessively-inherited disorder of iron over-absorption prevalent in Caucasian populations. Affected individuals for Type 1 HH are usually either homozygous for a cysteine to tyrosine amino acid substitution at position 282 (C282Y of the HFE gene, or compound heterozygotes for C282Y and for a histidine to aspartic acid change at position 63 (H63D. Molecular genetic testing for these two mutations has become widespread in recent years. With diverse testing methods and reporting practices in use, there was a clear need for agreed guidelines for haemochromatosis genetic testing. The UK Clinical Molecular Genetics Society has elaborated a consensus process for the development of disease-specific best practice guidelines for genetic testing. Methods A survey of current practice in the molecular diagnosis of haemochromatosis was conducted. Based on the results of this survey, draft guidelines were prepared using the template developed by UK Clinical Molecular Genetics Society. A workshop was held to develop the draft into a consensus document. The consensus document was then posted on the Clinical Molecular Genetics Society website for broader consultation and amendment. Results Consensus or near-consensus was achieved on all points in the draft guidelines. The consensus and consultation processes worked well, and outstanding issues were documented in an appendix to the guidelines. Conclusion An agreed set of best practice guidelines were developed for diagnostic, predictive and carrier testing for hereditary haemochromatosis and for reporting the results of such testing.

Proceso de instrucción con soporte tecnológico para la formación del docente en investigación

Directory of Open Access Journals (Sweden)

Ericka Naveda

2016-07-01

Full Text Available Se refiere una práctica de administración del proceso instruccional bajo la plataforma Moodle, para la facilitación de aprendizajes relativos a investigación, en la formación de docentes especialistas en Dificultades de Aprendizaje, en la Universidad Nacional Abierta de Venezuela. El objetivo general es analizar esta experiencia, en términos de logros, necesidades y mejoras requeridas; precisión del aprovechamiento de las TIC; determinación de condiciones para la sistematización correspondiente. La metodología se asocia a una investigación de corte aplicativo, en la cual se estudia la situación educativa, se formulan expectativas de cambios y mejoras y se estructura una propuesta de acción.

La alegoría: Orígenes y desarrollo de la filosofía desde los presocráticos hasta la Ilustración

OpenAIRE

Naddaf, Gerard

2007-01-01

Mucho se ha escrito sobre la célebre transición del muthos al logos, o del mito a la razón. Sin embargo, el tratamiento que se le ha dado al asunto de cómo respondieron los defensores del mito es más bien escaso. Ellos respondieron con mutho-logia; es decir, con un logos sobre el mito. Esta aproximación racional invocaba el mismo logos con el que generalmente se asocia la filosofía. De hecho, la philosophía y la muthología están tan estrechamente relacionadas por momentos que hasta el período...

Function of Receptor 1 in uptaking transferrin and its relation to iron deficiency and iron gestational preeclampsia

OpenAIRE

Gómez-Gutiérrez, Alejandra María; Parra-Sosa, Beatriz Elena; César Bueno-Sánchez, Julio

2013-01-01

La anemia ferropénica gestacional afecta al 48 % de las mujeres y se asocia con efectos deletéreos para la madre y el feto. Para la captación del hierro de la gestante es necesaria la expresión en el sincitiotrofoblasto de la glicoproteína receptor 1 de transferrina (TfR1). En ensayos celulares, en modelos animales y en humanos la deprivación de hierro se ha asociado a un aumento en la transcripción y expresión del TfR1, que se ha explicado como un mecanismo compensatorio para la captación de...

Conocimiento de los padres sobre hábitos bucales deformantes y traumas dentales asociados a las alteraciones bucales en niños de 4 a 10 años de edad de la I.E. Nuestros Héroes de la Guerra del Pacífico del distrito de Tacna, 2012

OpenAIRE

Aparcana Díaz, José Alfredo

2013-01-01

El objetivo se centró en determinar si se asocia el conocimiento que poseen los padres sobre hábitos bucales deformantes y traumas dentales con las alteraciones bucales en niños de 4 a 10 años de edad de la I.E. Nuestros Héroes de la Guerra del Pacífico del distrito de Tacna en el periodo 2012. El diseño fue no experimental, descriptivo transversal y de asociación. La población de estudio, fueron 248 padres y 248 hijos/as escolares de 4 a 10 años. Se utilizó un test de conocimientos de ...

Extended analyses of Se VII and Se VIII

International Nuclear Information System (INIS)

Vankleef, Th.A.M.; Joshi, Y.N.

1984-01-01

Joshi et al. (1984) have conducted an analysis of the 3d8 4s-3d8 4p transitions in As VII. The present investigation is concerned with an analysis of similar transitions in Se VIII. The selenium spectrum was photographed in the 400-1200-A wavelength region on a variety of normal-incidence spectrographs. Attention is given to least-squares-fit (LSF) and Hartree-Fock (HF) parameter values for the 3d9 4d configuration of Se VII, LSF and HF parameter values for the 3d8 4s and 3d8 4p configurations of Se VIII, the energy and composition of the levels of the 3d9 4d configuration of Se VII, classified lines in Se VII, energy levels and composition of the 3d8 4s configuration and the revised and newly determined levels of the 3d8 4p configuration of Se VIII, and newly classified lines of Se VIII. 15 references

The Ag2Se-HgSe-GeSe2 system and crystal structures of the compounds

International Nuclear Information System (INIS)

Parasyuk, O.V.; Gulay, L.D.; Romanyuk, Ya.E.; Olekseyuk, I.D.; Piskach, L.V.

2003-01-01

The phase diagram of the quasi-ternary Ag 2 Se-HgSe-GeSe 2 system at 298 K was investigated using X-ray phase analysis and metallography. The formation of five intermediate quaternary phases β (Ag ∼7.12-∼6.32 Hg ∼0.44-∼0.82 GeSe 6 ), γ (Ag ∼6.08-∼4.00 Hg ∼0.96-∼2.00 GeSe 6 ), δ (Ag 3.4 Hg 2.3 GeSe 6 ), ε (Ag ∼2.24-∼2.00 Hg ∼2.88-∼3.00 GeSe 6 ) and ∼Ag 1.4 Hg 1.3 GeSe 6 was established. The crystal structure of the β-phase (for the Ag 6.504 Hg 0.912 GeSe 6 composition) was determined using X-ray single crystal diffraction. It crystallizes in a cubic structure (space group F4-bar 3m) with the lattice parameter a=1.09026(4) nm. The crystal structure of the δ-phase (Ag 3.4 Hg 2.3 GeSe 6 ) was determined using X-ray powder diffraction (space group F4-bar 3m, a=1.07767(8) nm). The crystal structure determination of the γ-phase (space group Pmn2 1 ) was performed for the compositions Ag 5.6 Hg 1.2 GeSe 6 , Ag 4.8 Hg 1.6 GeSe 6 and Ag 4 Hg 2 GeSe 6 using X-ray powder diffraction. The crystal structure of the LT-Hg 2 GeSe 4 compound (space group I4-bar , a=0.56786(2), c=1.12579(5) nm) was confirmed by powder diffraction also.

EL DISCURSO DE LA VIOLENCIA EN EL MOVIMIENTO ANARQUISTA CHILENO (1890-1910

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Igor Goicovic Donoso

2011-10-01

Full Text Available Normalmente se vincula al anarquismo con un modo de vida sin orden, sin organización. Mecánicamente, se lo asocia al caos. Pero los propios pensadores anarquistas se encargaron de desmentir sistemáticamente esta visión tendenciosa y estrecha del pensamiento libertario. La contradicción fundamental denunciada por la teoría anarquista se encuentra en la tendencia natural de la humanidad a la plena libertad y en las compulsiones físicas, económicas e intelectuales que alienan al ser humano. En este contexto, para el anarquismo, el Estado se convierte en la encarnación del autoritarismo y, en consecuencia, en la base sobre la cual se sostiene el conjunto del sistema de dominación de clase

Human factors engineering plan for reviewing nuclear plant modernization programs

International Nuclear Information System (INIS)

O'Hara, John; Higgins, James

2004-12-01

The Swedish Nuclear Power Inspectorate reviews the human factors engineering (HFE) aspects of nuclear power plants (NPPs) involved in the modernization of the plant systems and control rooms. The purpose of a HFE review is to help ensure personnel and public safety by verifying that accepted HFE practices and guidelines are incorporated into the program and nuclear power plant design. Such a review helps to ensure the HFE aspects of an NPP are developed, designed, and evaluated on the basis of a structured top-down system analysis using accepted HFE principles. The review addresses eleven HFE elements: HFE Program Management, Operating Experience Review, Functional Requirements Analysis and Allocation, Task Analysis, Staffing, Human Reliability Analysis, Human-System Interface Design, Procedure Development, Training Program Development, Human Factors Verification and Validation, and Design Implementation

Human factors engineering plan for reviewing nuclear plant modernization programs

Energy Technology Data Exchange (ETDEWEB)

O' Hara, John; Higgins, James [Brookhaven National Laboratory, Upton, NY (United States)

2004-12-01

The Swedish Nuclear Power Inspectorate reviews the human factors engineering (HFE) aspects of nuclear power plants (NPPs) involved in the modernization of the plant systems and control rooms. The purpose of a HFE review is to help ensure personnel and public safety by verifying that accepted HFE practices and guidelines are incorporated into the program and nuclear power plant design. Such a review helps to ensure the HFE aspects of an NPP are developed, designed, and evaluated on the basis of a structured top-down system analysis using accepted HFE principles. The review addresses eleven HFE elements: HFE Program Management, Operating Experience Review, Functional Requirements Analysis and Allocation, Task Analysis, Staffing, Human Reliability Analysis, Human-System Interface Design, Procedure Development, Training Program Development, Human Factors Verification and Validation, and Design Implementation.

Phase diagram of Se-CaIn4Se7 system

International Nuclear Information System (INIS)

Musaeva, R.I.; Aliev, I.I; Ismailova, F.I; Aliev, A.A

2011-01-01

Full text: The Se-CaIn 4 Se 7 system has been studied using methods of differential thermal analysis, X-ray diffraction, micro structural analysis, density measurements and its phase diagram has been constructed. It has been established that the section Se-CaIn 4 Se 7 is a quasibinary section of the ternary system Ca-In-Se. At room temperature, on the basis of CaIn 2 Se 4 and Se no solid solution has been found

On Some Physical Properties of GeSe3-Sb2Se3-ZnSe Thin Films and Their Radiation Response

International Nuclear Information System (INIS)

Hosni, H.M.M.A.

2010-01-01

Thin films of the chalcogenides GeSe 3 , Sb 2 Se 3 , ZnSe, (GeSe 3 )80(Sb 2 Se 3 )20 and (GeSe 3 )70(Sb 2 Se 3 )10(ZnSe)20, are prepared by thermal evaporation onto glass substrates. The effect of ZnSe incorporation with both GeSe 3 , Sb 2 Se 3 results in amorphous (GeSe 3 )70(Sb 2 Se 3 )10(ZnSe)20 composition as obtained from the X-ray analysis. Electrical measurements reveal a decrease in dc activation energy, ΔEdc, and an increase in ac activation energy, ΔEac, for (GeSe 3 )70(Sb 2 Se 3 )10(ZnSe)20 as compared with (GeSe 3 )80(Sb 2 Se 3 )20. Optical energy gap, Eg, and band tail width, Ee, are estimated in UV/VIS spectral region for fresh and γ-irradiated films, revealing a decrease in Eg and an increase in Ee for ZnSe and (GeSe 3 )70(Sb 2 Se 3 )10(ZnSe)20 compositions, with irradiation dose.

Human factors and ergonomics for primary care.

Science.gov (United States)

Bowie, Paul; Jeffcott, Shelly

2016-03-01

In the second paper of this series, we provide a brief overview of the scientific discipline of human factors and ergonomics (HFE). Traditionally the HFE focus in healthcare has been in acute hospital settings which are perceived to exhibit characteristics more similar to other high-risk industries already applying related principles and methods. This paper argues that primary care is an area which could benefit extensively from an HFE approach, specifically in improving the performance and well-being of people and organisations. To this end, we define the purpose of HFE, outline its three specialist sub-domains (physical, cognitive and organisational HFE) and provide examples of guiding HFE principles and practices. Additionally, we describe HFE issues of significance to primary care education, improvement and research and outline early plans for building capacity and capability in this setting.

Acoso escolar y habilidades sociales en alumnado de educación básica

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Brenda Mendoza González

2017-01-01

Full Text Available Se describe la relación de habilidades sociales con el rol de participación en acoso escolar. Participaron 557 alumnos (educación primaria y secundaria. Se aplicaron dos instrumentos: competencias en habilidades sociales y bullying (índice α = 0.95. Los resultados describen cuatro tipos de alumnos (víctima, víctima/agresor en violencia escolar y bullying y el alumnado que no se involucra. Se observa que el alumnado que no participa en episodios de agresión tiene más habilidades sociales que los que sí se involucran. Los grupos en mayor riesgo de ser victimizados son los alumnos de primaria sin identificarse diferencias entre hombres y mujeres. Se concluye que el déficit en habilidades sociales se asocia con la participación en episodios de acoso escolar.

Semiconductor-metal transition of Se in Ru-Se Catalyst Nanoparticles

Science.gov (United States)

Babu, P. K.; Lewera, Adam; Oldfield, Eric; Wieckowski, Andrzej

2009-03-01

Ru-Se composite nanoparticles are promising catalysts for the oxygen reduction reaction (ORR) in fuel cells. Though the role of Se in enhancing the chemical stability of Ru nanoparticles is well established, the microscopic nature of Ru-Se interaction was not clearly understood. We carried out a combined investigation of ^77Se NMR and XPS on Ru-Se nanoparticles and our results indicate that Se, a semiconductor in elemental form, becomes metallic when interacting with Ru. ^77Se spin-lattice relaxation rates are found to be proportional to T, the well-known Korringa behavior characteristic of metals. The NMR results are supported by the XPS binding energy shifts which suggest that a possible Ru->Se charge transfer could be responsible for the semiconductor->metal transition of Se which also makes Ru less susceptible to oxidation during ORR.

TOPOLOGIAS DOS CORPOS DE HOMENS GAYS: DESLOCAMENTOS NA PRODUÇÃO DE SENSIBILIDADES BIOPOLÍTICAS

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Luís Henrique Sacchi dos Santos

2013-01-01

Full Text Available Este artículo mapea los desplazamientos de la producción biopolítica de los cuerpos de hombres gais en dos momentos distintos en Brasil. El primero se relaciona con el discurso del riesgo a la infección por VIH que intervino dichos cuerpos, constituyéndolos como desterrados. El segundo se asocia con la exhibición de cuerpos-que-importan en páginas electrónicas dirigidas a hombres gais, en las cuales se explicita su sujeción. Se afirma que esos dos momentos están implicados en la producción de sensibilidades biopolíticas diferenciadas por la mezcla de regulaciones de poder del Estado y del mercado neoliberal.

El farmacéutico comunitario, necesario en el abordaje de la hipertensión arterial y el riesgo vascular

Directory of Open Access Journals (Sweden)

Iracheta M

2014-09-01

Full Text Available En la actualidad la hipertensión arterial (HTA es uno de los problemas de salud pública más importantes en los países desarrollados. Se trata de una enfermedad que aumenta considerablemente el riesgo vascular y que se caracteriza por ser asintomática, fácil de detectar y, en la mayoría de los casos, de tratar, pero que se asocia a incapacidad, disminución de la calidad de vida (puede lesionar órganos como el corazón, riñones, cerebro, retina… y, finalmente, mortalidad prematura si no se previene y se trata de forma adecuada. Es la causa de por lo menos la mitad de las muertes por cardiopatías y por accidente cerebrovascular.

Bio-fortification and isotopic labelling of Se metabolites in onions and carrots following foliar application of Se and 77Se

DEFF Research Database (Denmark)

Kápolna, Emese; Laursen, Kristian H.; Husted, Søren

2012-01-01

Se. The 77Se- labelled metabolites in onions were predominantly γ-glutamyl-77Se-selenomethyl-selenocysteine (γ-glu-Me77SeCys), 77Se-methylselenocysteine (Me77SeCys) and 77Se-selenomethionine (77SeMet). Furthermore, we report here for the first time the finding in carrots of the bioactive Me77SeCys...

Evaluación de una intervención educativa implementada a través de internet y de la telefonía móvil para la prevención del riesgo conductual de cancer en adolescentes de España y México y su entorno adulto

OpenAIRE

Lana Pérez, Alberto

2012-01-01

El cáncer continúa siendo un problema de primer orden mundial y su control no es todo lo bueno que cabría esperar, especialmente si se tiene en cuenta que en gran medida se asocia a factores de riesgo vinculados al estilo de vida potencialmente modificables. La importancia de las conductas como factores de riesgo de cáncer está fuera de toda duda. El hábito tabáquico y la alimentación poco saludable son las más relevantes, pero también está bien documentado el incremento del riesgo por el con...

Obesidad en la mujer Obesity in women

OpenAIRE

P. Riobó; B. Fernández Bobadilla; M. Kozarcewski; J. M. Fernández Moya

2003-01-01

La obesidad se ha convertido en un importante problema de salud pública en todos los países desarrollados. En las mujeres adquiere unas connotaciones ligeramente diferentes debido, además de a la mayor prevalencia, a que el bajo nivel socioeconómico es factor de riesgo sólo en la mujer. Además de ser factor de riesgo cardiovascular en la mujer se asocia a una aumento del riesgo de cáncer de mama y de endometrio y a poliquistosis ovárica e infertilidad. En las mujeres el control de peso tiene ...

Trombosis venosa profunda masiva de miembro superior secundaria a fractura de tercio medio de clavícula. Caso clínico

OpenAIRE

Úbeda-Pérez de Heredia, Í.; Sobrá-Hidalgo, G.Á.

2016-01-01

Resumen Objetivo: La trombosis venosa profunda del miembro superior es una entidad rara que se asocia con el uso de catéteres, estados de hipercoagulabilidad, anticonceptivos orales, neoplasias, síndrome de costilla cervical o de los escalenos, fracturas de clavícula y trombosis inducida por el esfuerzo. Método: Varón de 53 años que desarrolló una trombosis venosa de las venas axilar, cefálica y basílica tres días después de sufrir una fractura de tercio medio de clavícula que se inmovilizó...

Trombosis venosa profunda masiva de miembro superior secundaria a fractura de tercio medio de clavícula. Caso clínico

OpenAIRE

Í. Úbeda-Pérez de Heredia; G.Á. Sobrá-Hidalgo

2016-01-01

Objetivo: La trombosis venosa profunda del miembro superior es una entidad rara que se asocia con el uso de catéteres, estados de hipercoagulabilidad, anticonceptivos orales, neoplasias, síndrome de costilla cervical o de los escalenos, fracturas de clavícula y trombosis inducida por el esfuerzo. Método: Varón de 53 años que desarrolló una trombosis venosa de las venas axilar, cefálica y basílica tres días después de sufrir una fractura de tercio medio de clavícula que se inmovilizó inicia...

Identificación e implementación de paquetes tecnológicos en ganadería vacuna de doble propósito: Caso Manabí-Ecuador

OpenAIRE

Torres, Yenny; Rivas, José; De Pablos-Heredero, Carmen; Perea, José; Toro-Mujica, Paula; Angón, Elena; García, Antón

2014-01-01

El avance en los sistemas ganaderos se asocia a la implementación de tecnologías en la producción y a la mejora de sus ingresos. El objetivo del presente estudio fue la identificación e implementación de paquetes tecnológicos y su relación con los resultados productivos en vacuno de doble propósito de la provincia de Manabí, Ecuador en dos zonas climáticas: el Bosque seco tropical y el húmedo tropical. Se agrupan 25 tecnologías en seis paquetes tecnológicos (PT) seleccionadas mediante una met...

Determinantes socio-económicas de la desnutrición global infantil en la Localidad de Ciudad Bolívar (Bogotá, Colombia) en el año 2011

OpenAIRE

Ducuara Mora, Pedro Enrique

2012-01-01

La desnutrición infantil y la pobreza se encuentran asociadas y estas a su vez con el progreso de los países. Conocer las determinantes sociales y económicas de la niñez que padece de bajo peso es necesario para crear escenarios propicios para el adecuado desarrollo de la primera infancia y de esta manera contribuir con la superación de la pobreza en el marco de sistemas sanitarios equitativos. Se realiza una descripción de las características socio-económicas y un análisis de posibles asocia...

Calidad de vida relacionada a la salud tras una intervención con dieta mediterránea y ejercicio físico en pacientes con síndrome metabólico

OpenAIRE

Landaeta Díaz, Leslie

2012-01-01

El síndrome metabólico (SMet) se asocia con depresión, estrés psicosocial y peor calidad de vida relacionada a la salud. La dieta mediterránea y el ejercicio físico tienen un efecto positivo sobre el SMet aunque se desconoce su impacto sobre la calidad de vida relacionada a la salud y la capacidad física en estos pacientes. Objetivos: Estudiar el efecto de un modelo de dieta mediterránea, combinada o no con un programa de ejercicio físico de moderada a alta intensidad, sobre...

La innovación estratégica como predictora de la innovación organizativa en las instituciones de educación superior en México

OpenAIRE

Eréndira Fierro Moreno

2015-01-01

El objetivo de este Artículo es determinar a qué grado se asocia la innovación estratégica con la innovación organizativa u organizacional y el efecto de dicha asociación. Con base en la revisión de la literatura y la perspectiva teórica de recursos y capacidades se formularon las hipótesis de la investigación. Por medio de un enfoque cuantitativo, un diseño de investigación transversal de alcance descriptivo/correlacional y la percepción de 235 empleados y directivos de 32 instituciones de ...

Factores asociados a la hipertensión arterial en el adulto mayor según la subregión

Directory of Open Access Journals (Sweden)

Nini J. García-Castañeda

2016-11-01

Conclusiones: La condición de ser: adulto mayor viejo, sexo femenino, afrocolombiano, residir en estrato cero y presentar un estado nutricional moderado, diabetes, problemas del corazón y cerebro, se asocia con la hipertensión arterial. Se requiere la implementación de las siete P (7 P de la salud pública: las políticas públicas, la planeación en salud, la población vulnerable, la promoción de la salud, la prevención del riesgo, la participación comunitaria y los principios éticos.

Relación estructura-función de la proteína epididimaria de rata "DE", y su potencial uso para el desarrollo de un método de regulación de la fertilidad

OpenAIRE

Ellerman, Diego A.

2001-01-01

La glicoproteína epididimaria de rata "DE" se asocia al espermatozoide durante la maduración, y participa en el proceso de fusión de gametas a través de sitios complementarios presentes en la superficie del ovocito. Con el fin de comprender los mecanismos involucrados en la participación de DE en dicho proceso, se estudió la importancia de la estructura de DE para la actividad de la proteína. El clonado del ADNc de DE permitió obtener la secuencia de los 227 aminoácidos (aa) de la proteína. E...

Síndrome de Tourette

OpenAIRE

Maniega López, Raisa

2016-01-01

Introducción: El ST o Síndrome de Tourette descubierto por el doctor Gilles Tourette en el año 1885, se caracteriza por la presencia de varios tics motores y sónicos además de fallos en la fluencia del habla. Este síndrome tiene un componente hereditario y las descompensaciones de dopamina parecen tener algo que ver con su aparición. Además del ST los enfermos pueden padecer otras formas de la enfermedad como el trastorno de tic crónico o transitorio. Esta enfermedad también se asocia con otr...

Cierre percutáneo de conducto arterioso mediante un asa arteriovenosa en un paciente con síndrome de la cimitarra

OpenAIRE

Luis Alexis Arévalo Salas; Liborio Solano Fiesco; Jorge Luis Villatoro Fernández

2017-01-01

Introducción: El síndrome de la cimitarra consiste en una rara malformación, caracterizada por una conexión anómala parcial de una o ambas venas pulmonares derechas a la vena cava inferior, hipoplasia de pulmón derecho y circulación sistémica desde la aorta descendente. El síndrome de la cimitarra en ocasiones se asocia con otras malformaciones congénitas, entre las que se incluye la persistencia del conducto arterioso (PCA). Caso clínico: Paciente de sexo femenino de cuatro años de edad c...

Evaluación de factores asociados a la ansiedad social y a otras psicopatologías en adolescentes

OpenAIRE

Zubeidat, Ihab; Fernández Parra, Antonio; Sierra, Juan Carlos; Salinas, José María

2008-01-01

Introducción El estudio de factores asociados a la ansiedad y fobia social constituye un tema de reciente interés. Concretamente, la timidez infantil parece actuar como una expresión temprana de la fobia social que más tarde se puede consolidar como cuadro clínico. La percepción de los hijos sobre la presencia de ciertas psicopatologías y de determinados estilos de crianza de los padres se asocia a la aparición de la fobia social en la adolescencia. El trastorno de ansiedad social durante la ...

Análisis evolutivo del concepto de adaptación a la diabetes tipo 2

OpenAIRE

José Martín Castro-Espinoza; Esther C. Gallegos-Cabriales; Keville Frederickson

2015-01-01

El concepto de adaptación tiene diferentes aplicaciones y acepciones. En personas que viven con diabetes tipo 2 (DT2) se asocia con la observancia del tratamiento y el control glucémico. Es utilizado frecuentemente en la literatura de salud pero no está claro qué signi- fica en personas que viven con esta enfermedad, por lo que el propósito de esta investigación fue analizar el concepto de adaptación a la DT2. Metodología: se utilizó el método de análisis evolutivo de concepto de Rodger...

Absorption of Manganese and Iron in a Mouse Model of Hemochromatosis

Science.gov (United States)

Kim, Jonghan; Buckett, Peter D.; Wessling-Resnick, Marianne

2013-01-01

Hereditary hemochromatosis, an iron overload disease associated with excessive intestinal iron absorption, is commonly caused by loss of HFE gene function. Both iron and manganese absorption are regulated by iron status, but the relationships between the transport pathways of these metals and how they are affected by HFE-associated hemochromatosis remain poorly understood. Loss of HFE function is known to alter the intestinal expression of DMT1 (divalent metal transporter-1) and Fpn (ferroportin), transporters that have been implicated in absorption of both iron and manganese. Although the influence of HFE deficiency on dietary iron absorption has been characterized, potential effects on manganese metabolism have yet to be explored. To investigate the role of HFE in manganese absorption, we characterized the uptake and distribution of the metal in Hfe −/− knockout mice after intravenous, intragastric, and intranasal administration of 54Mn. These values were compared to intravenous and intragastric administration of 59Fe. Intestinal absorption of 59Fe was increased and clearance of injected 59Fe was also increased in Hfe−/− mice compared to controls. Hfe −/− mice displayed greater intestinal absorption of 54Mn compared to wild-type Hfe+/+ control mice. After intravenous injection, the distribution of 59Fe to heart and liver was greater in Hfe −/− mice but no remarkable differences were observed for 54Mn. Although olfactory absorption of 54Mn into blood was unchanged in Hfe −/− mice, higher levels of intranasally-instilled 54Mn were associated with Hfe−/− brain compared to controls. These results show that manganese transport and metabolism can be modified by HFE deficiency. PMID:23705020

Impactos del turismo residencial percibidos por la población local: una aproximación cualitativa desde la teoría del intercambio social

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Carlos Monterrubio

2018-01-01

Full Text Available Desde la teoría del intercambio social, se analizan los impactos del turismo residencial en Puerto Morelos, México. Con base en entrevistas a residentes permanentes, se evidencia que el turismo residencial se asocia con el empleo, el efecto multiplicador, la difusión de la cultura, el cuidado del entorno natural y acciones altruistas con locales. El incremento del precio de los inmuebles y de la competencia empresarial son considerados costos del fenómeno. Los pobladores realizan una valoración de los beneficios económicos y de los costos socioculturales y medioambientales a nivel individual y colectivo para definir su posición frente al turismo residencial.

Políticas de protección de la arquitectura patrimonial iquiqueña

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Eugenio Gutiérrez Gebauer

2001-07-01

Full Text Available Que la ciudad de Iquique, haya sido un área urbana que ha estado desde siempre alejada de los grandes centros urbanos, aislada por el desierto, contacto tradicional por vía marítima y que haya albergado un importante porcentaje de población foránea, con importantes colonias residentes, y a lo que se suma la propia peculiaridad de la influencia del período del auge del salitre, han sido elementos que han marcado y explican las características de haberse constituido en un importante centro de intercambio cultural, al que se ha sumado un tipo de vida particular al que se asocia su peculiar arquitectura.

Impactos sociales de la actividad petrolera en Ecuador: un análisis de los indicadores

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Jarrín , María Cristina

2005-01-01

Full Text Available El presente artículo explora en qué medida las zonas en las cuales se desarrolla la extracción petrolera, muestran similitudes y diferencias con el país y el resto de la Amazonía, en una gama de 100 indicadores estadísticos sociales particularidades. Se utilizaron datos provenientes de INFOPLAN, SIISE, series censales, e información petrolera. Se estudió el comportamiento de variables, las correlaciones entre ellas, se efectuó un análisis de componentes principales y dendogramas de agrupamiento de los cantones. El resultado es que existen aspectos en los cuales tales unidades administrativas se diferencias de las demás, pero la presencia de petróleo no es el principal factor que se asocia a la variación socioeconómica en la Amazonía ecuatoriana.

Human factors/ergonomics as a systems discipline? "The human use of human beings" revisited.

Science.gov (United States)

Hollnagel, Erik

2014-01-01

Discussions of the possible future of Human factors/ergonomics (HFE) usually take the past for granted in the sense that the future of HFE is assumed to be more of the same. This paper argues that the nature of work in the early 2010s is so different from the nature of work when HFE was formulated 60-70 years ago that a critical reassessment of the basis for HFE is needed. If HFE should be a systems discipline, it should be a soft systems rather than a hard systems discipline. It is not enough for HFE to seek to improve performance and well-being through systems design, since any change to the work environment in principle alters the very basis for the change. Instead HFE should try to anticipate how the nature of work will change so that it can both foresee what work will be and propose what work should be. Copyright © 2013 Elsevier Ltd and The Ergonomics Society. All rights reserved.

One-step synthesis of PbSe-ZnSe composite thin film

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Abe Seishi

2011-01-01

Full Text Available Abstract This study investigates the preparation of PbSe-ZnSe composite thin films by simultaneous hot-wall deposition (HWD from multiple resources. The XRD result reveals that the solubility limit of Pb in ZnSe is quite narrow, less than 1 mol%, with obvious phase-separation in the composite thin films. A nanoscale elemental mapping of the film containing 5 mol% PbSe indicates that isolated PbSe nanocrystals are dispersed in the ZnSe matrix. The optical absorption edge of the composite thin films shifts toward the low-photon-energy region as the PbSe content increases. The use of a phase-separating PbSe-ZnSe system and HWD techniques enables simple production of the composite package.

DIETA Y PREVENCIÓN SECUNDARIA DE LA ENFERMEDAD CARDIOVASCULAR

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Luis Alberto Ángel Arango

2011-01-01

Conclusiones. Las dietas de tipo mediterráneo y reductora del colesterol ricas en ácidos grasos omega-3 probablemente tienen un efecto favorable en la prevención cardiovascular secundaria (B-IIa, este efecto desaparece si se asocia con tratamiento farmacológico de los factores cardiovasculares de riesgo (B-III. Los ácidos grasos omega-3 probablemente incrementan la mortalidad en pacientes con angina y favorecen la recurrencia de arritmias ventriculares (B-III.

La corrección del déficit de 25-OH-vitamina D mejora el control del hiperparatiroidismo secundario y el estado inflamatorio de pacientes estables en hemodiálisis

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Raquel Ojeda López

2018-01-01

Conclusiones: La corrección del déficit de 25-OH-D en pacientes en HD se asocia a un mejor control del hiperparatiroidismo secundario con menores dosis de análogos de vitamina D y a una mejoría en el estado inflamatorio de estos pacientes. Nuestros resultados apoyan la recomendación de determinar niveles de 25-OH-D y corregir el déficit en pacientes en HD.

Human factors engineering program review model

International Nuclear Information System (INIS)

1994-07-01

The staff of the Nuclear Regulatory Commission is performing nuclear power plant design certification reviews based on a design process plan that describes the human factors engineering (HFE) program elements that are necessary and sufficient to develop an acceptable detailed design specification and an acceptable implemented design. There are two principal reasons for this approach. First, the initial design certification applications submitted for staff review did not include detailed design information. Second, since human performance literature and industry experiences have shown that many significant human factors issues arise early in the design process, review of the design process activities and results is important to the evaluation of an overall design. However, current regulations and guidance documents do not address the criteria for design process review. Therefore, the HFE Program Review Model (HFE PRM) was developed as a basis for performing design certification reviews that include design process evaluations as well as review of the final design. A central tenet of the HFE PRM is that the HFE aspects of the plant should be developed, designed, and evaluated on the basis of a structured top-down system analysis using accepted HFE principles. The HFE PRM consists of ten component elements. Each element in divided into four sections: Background, Objective, Applicant Submittals, and Review Criteria. This report describes the development of the HFE PRM and gives a detailed description of each HFE review element

Los inmigrantes como amenaza. Procesos migratorios en la televisión española

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Mª Carmen Albert Guardiola

2010-01-01

Full Text Available La mayor parte de las investigaciones desarrolladas en torno a la imagen mediática de los procesos migratorios destacan la tendencia hacia su problematización, de forma que se asocia a la población inmigrante con amenazas sociales, económicas, culturales, con la desviación, delincuencia, ilegalidad, etc. Tomando como referencia el caso de España, en este artículo se analiza la manera en que los noticiarios televisivos construyen aquellas noticias relacionadas con la población inmigrante. Con este fin, se han recogido un total de 145 noticias emitidas en 105 programas informativos de cuatro cadenas de televisión (tres de ámbito nacional y una regional, a cuyos contenidos se han aplicado, fundamentalmente, técnicas cualitativas de análisis.

Adrián Muñoz. La piel de tigre y la serpiente: la identidad de los nāth-yoguis a través de sus leyendas

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Luis Óscar Gómez Rodríguez

2013-05-01

Full Text Available El doctor Adrián Muñoz nos ofrece una obra erudita que demuestra un conocimiento amplio y detallado de una literatura que puede parecer muy especializada, incluso muy limitante en su particularidad y su superabundancia de textos y variantes textuales. Se trata de la literatura legendaria de un linaje hagiográfico complejo y heterogéneo, el nātha-sampradāya. Este linaje se asocia principalmente con la tradición hinduista, aunque también se entrelaza con la tradición de los 84 siddhas de la corriente budista. Muñoz se concentra en las narrativas legendarias y en el papel que desempeñan estas en la creación de la identidad religiosa de los seguidores del nāth-panth.

Design engineer perceptions and attitudes regarding human factors application to nuclear power plant design

International Nuclear Information System (INIS)

Ma, R.; Jones, J. M.

2006-01-01

With the renewed interest in nuclear power and the possibility of constructing new reactors within the next decade in the U.S., there are several challenges for the regulators, designers, and vendors. One challenge is to ensure that Human Factors Engineering (HFE) is involved, and correctly applied in the life-cycle design of the Nuclear Power Plant (NPP). As an important part of the effort, people would ask: 'is the system-design engineer effectively incorporating HFE in the NPPs design?' The present study examines the sagacity of Instrumentation and Control design engineers on issues relating to awareness, attitude, and application of HFE in NPP design. A questionnaire was developed and distributed, focusing on the perceptions and attitudes of the design engineers. The responses revealed that, while the participants had a relatively high positive attitude about HFE, their awareness and application of HFE were moderate. The results also showed that senior engineers applied HFE more frequently in their design work than young engineers. This study provides some preliminary results and implications for improved HFE education and application in NPP design. (authors)

Terapia celular para el tratamiento de la diabetes: Más allá de las células madre

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María Laura Gimeno

2011-06-01

Full Text Available La diabetes tipo 1 es una enfermedad de etiología autoinmune que se caracteriza por la destrucción de las células ß pancreáticas, produciendo un déficit absoluto de insulina. El tratamiento clínico estándar consiste en la aplicación de insulina. Sin embargo, en un número importante de pacientes y debido a la dificultad en lograr un control metabólico preciso, generalmente se asocia con complicaciones graves a nivel vascular con repercusión renal y ocular entre otras. Por otra parte, un estricto control metabólio, a menudo se asocia con hipoglucemias con riesgo de muerte. Esto motivó la investigación y el desarrollo de alternativas de tratamiento. Una de ellas es el trasplante de células productoras de insulina, las células ß, obtenidas por medio del aislamiento y trasplante de islotes de un páncreas cadavérico. Los mejores resultados con esta modalidad de trasplante se obtuvieron con la inyección sucesiva de islotes pancreáticos de diferentes donantes y terapia inmunosupresora exenta de corticoides. Sin embargo, la escasez de órganos por un lado, y el hecho de que cada implante de islotes de otro páncreas aumenta las posibilidades de rechazo inmunológico, hace que este tratamiento se vea limitado a centros de alta experiencia y pacientes muy seleccionados. Asimismo, las drogas inmunosupresoras que deben administrarse de por vida, pueden producir efectos no deseados en el organismo. La medicina regenerativa abre la posibilidad de utilizar células madre con capacidad de diferenciarse en células productoras de insulina, utilizando de manera conjunta factores tróficos que serían capaces de estimular a las propias células madre de cada parénquima.

Structure and optical properties of GaSe-CdSe composites driven by Cd intercalation in GaSe lamellar crystals

International Nuclear Information System (INIS)

Caraman, Iuliana; Kantser, Valeriu; Evtodiev, Igor; Untila, Dumitru; Dmitroglo, Liliana; Leontie, Liviu; Arzumanyan, Grigory

2015-01-01

A new composite material composed of GaSe and CdSe has been obtained by treatment of GaSe single-crystal lamellas in Cd vapors at temperatures of 773-853 K and intercalation of Cd interlayers. The structure and optical properties of the GaSe-CdSe composite material have been studied. The content of CdSe crystallites was found to grow with increasing treatment temperature or with increasing duration of treatment at a constant temperature. Analysis of XRD, PL, XPS, AFM, and Raman patterns has shown that the heterogeneous composite composed of micro and nanocrystallites of CdSe in GaSe can be obtained by Cd intercalation in a temperature range of 753-853 K. On the basis of Raman spectrum, the vibrational modes of the composite have been identified. The PL of these materials contains emission bands of free and bound excitons, donor-acceptor bands, and bands of recombination via impurity levels. The PL emission spectra measured at a temperature of 78 and 300 K for the composites result from the overlapping of the emission bands of the components of GaSe doped with Cd and the CdSe crystallites. (authors)

Stable and metastable phases in reciprocal systems PbSe + Ag2I2 Ag2Se + PbI2 and PbSe + CdI2 = CdSe + PbI2

International Nuclear Information System (INIS)

Odin, I.N.; Grin'ko, V.V.; Kozlovskij, V.F.; Safronov, E.V.

2005-01-01

Mutual system PbSe + Ag 2 I 2 = Ag 2 Se + PbI 2 is investigated. It is shown that diagonal Ag 2 Se-PbI 2 is stable. Liquidus surface and isothermal section at 633 K of phase diagram of PbSe-Ag 2 Se-PbI 2 system are built. Transformations directing to crystallization metastable ternary compound forming in PbSe-PbI 2 system and metastable polytype modifications of lead iodide in PbSe-Ag 2 Se-PbI 2 system at 620-685 K are studied. By hardening from molten state (1150-1220 K) new interstitial metastable phases crystallizing in CdCl 2 structural type are obtained in PbSe-Ag 2 Se-PbI 2 and PbSe + CdI 2 = CdSe + PbI 2 systems [ru

Synthesis and characterization of ZnSe:Fe/ZnSe core/shell nanocrystals

Energy Technology Data Exchange (ETDEWEB)

Yang, Lin; Zhu, Jianguo, E-mail: yanglin_1028@163.com; Xiao, Dingquan

2014-04-15

High-quality ZnSe:Fe/ZnSe core/shell nanocrystals were prepared via a hydrothermal microemulsion technique. Effective surface passivation of monodisperse ZnSe:Fe nanocrystals is achieved by overcoating them with a ZnSe shell. The samples were characterized by means of XRD, EDX, TEM, PSD, XPS, photoluminescence, and Raman spectrum. The results show that the as-synthesized nanocrystals are cubic zinc blende ZnSe structure with high purity and the average particle size of ZnSe:Fe/ZnSe core/shell nanocrystal is larger than that of ZnSe:Fe core. The growth of ZnSe shell causes a small red shift in PL spectra, and then the PL quantum yield (QY) increases from 16% before shell growth to the maximum of 37% after increasing shell thickness up to 1.2 monolayers (ML). Moreover, both transverse optic (TO) and longitudinal optic (LO) phonon modes of ZnSe are shifted toward lower frequency as compared with the reported ones. -- Highlights: • ZnSe:Fe/ZnSe core/shell QDs were prepared by a hydrothermal microemulsion method. • ZnSe shell efficiently passivates surface defects by serving as a physical barrier. • The particle size and PL properties can be turned with the growth of ZnSe shell. • The luminescence efficiency and stability of QDs could be improved in this manner.

Measurement of 76Se and 78Se (γ, n) cross sections

International Nuclear Information System (INIS)

Kitatani, Fumito; Harada, Hideo; Goko, Shinji; Utsunomiya, Hiroaki; Akimune, Hidetoshi; Toyokawa, Hiroyuki; Yamada, Kawakatsu

2011-01-01

The (γ, n) cross sections of Se isotopes ( 76 Se, 78 Se) were measured to supply fundamental data for estimating the inverse reaction cross section, i.e., the 79 Se(n, γ) 80 Se cross section. The enriched samples and a reference 197 Au sample were irradiated with laser-Compton scattering (LCS) γ-rays. The excitation function of each (γ, n) cross section was determined for the energy range from each near neutron separation energy to the threshold energy of (γ, 2n) reaction. The energy point corresponding to each cross section was deduced using the accurately determined energy distribution of LCS γ-rays. Systematic (γ, n) cross sections for Se isotopes including 80 Se were compared with those calculated by using a statistical model calculation code TALYS. (author)

Analogía y metáfora en el análisis organizacional. Un ejemplo: la organización como cárcel

Directory of Open Access Journals (Sweden)

Jairo E. Carrillo G.

2003-01-01

Full Text Available Este ensayo busca mostrar cómo la analogía y la metáfora constituyen recursos metodológicos adecuados para describir y comprender aspectos centrales de la dinámica organizacional, no accesibles por otros métodos. Como ilustración se hará énfasis en la metáfora que asocia las organizaciones con el concepto de prisión psíquica o cárcel virtual

ANALOGÍA Y METÁFORA EN EL ANÁLISIS ORGANIZACIONAL

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Jairo Carrillo

2003-07-01

Full Text Available Este ensayo busca mostrar cómo la analogía y la metáfora constituyen recursos metodológicos adecuados para describir y comprender aspectos centrales de la dinámica organizacional, no accesibles por otros métodos. Como ilustración se hará énfasis en la metáfora que asocia las organizaciones con el concepto de prisión psíquica o cárcel virtual.

Dimensiones de la comunicación y de la información: la doble faz de la realidad social

OpenAIRE

Eduardo Andrés Vizer

2009-01-01

El artículo relaciona información y comunicación, estructura y proceso social. Además, propone tres dimensiones del proceso de comunicación y su relación con la abducción y los procesos indiciales de Peirce. También asocia dimensiones comunicacionales con categorías de análisis social. Se persigue el desarrollo asistemático de un paradigma sociocomunicacional conforme a proposiciones de Imre Lakatos.

Dimensiones de la comunicación y de la información: la doble faz de la realidad social

Directory of Open Access Journals (Sweden)

Eduardo Andrés Vizer

2009-01-01

Full Text Available El artículo relaciona información y comunicación, estructura y proceso social. Además, propone tres dimensiones del proceso de comunicación y su relación con la abducción y los procesos indiciales de Peirce. También asocia dimensiones comunicacionales con categorías de análisis social. Se persigue el desarrollo asistemático de un paradigma sociocomunicacional conforme a proposiciones de Imre Lakatos.

Thermoelectric prospects of chemically deposited PbSe and SnSe thin films

Science.gov (United States)

Nair, P. K.; Martínez, Ana Karen; Rosa García Angelmo, Ana; Barrios Salgado, Enue; Nair, M. T. S.

2018-03-01

Thin films of PbSe of 400-600 nm in thickness, were obtained via chemical deposition from a solution containing lead nitrate, thiourea and selenosufate. SnSe thin films of 90-180 nm in thickness, were also obtained by chemical deposition from a solution containing selenosulfate. Optical and electrical properties of these thin films were significantly altered by heating them in selenium vapor at 300 °C. Thin film PbSe has a bandgap (Eg) of 1.17 eV (direct gap, forbidden transitions), which decreases to 0.77 eV when it has been heated. Its electrical conductivity (σ) is p-type: 0.18 Ω-1 cm-1 (as-prepared), and 6.4 Ω-1 cm-1 when heated. Thin film SnSe is of orthorhombic crystalline structure which remains stable when heated at 300 °C, but its Eg increases from 1.12 eV (indirect) in as-prepared film to 1.5 eV (direct, forbidden transitions) upon heating. Its electrical conductivity is p-type, which increases from 0.3 Ω-1 cm-1 (as-prepared) to 1 Ω-1 cm-1 when heated (without Se-vapor). When SnSe film is heated at 300 °C in the presence of Se-vapor, they transform to SnSe2, with Eg of 1.5 eV (direct, forbidden) with n-type electrical conductivity, 11 Ω-1 cm-1. The Seebeck coefficient for the PbSe films is: +0.55 mV K-1 (as prepared) and +0.275 mV K-1 (heated); for SnSe films it is: +0.3 mV K-1 (as prepared) and +0.20 mV K-1 (heated); and for SnSe2 film, - 0.35 mV K-1. A five-element PbSe-SnSe2-PbSe-SnSe2-PbSe thermoelectric device demonstrated 50 mV for a temperature difference ΔT = 20 °C (2.5 mV K-1). For SnSe-SnSe2-SnSe-SnSe2-SnSe device, the value is 15 mV for ΔT = 20 °C (0.75 mV K-1). Prospect of these thin films in thermoelectric devices of hybrid materials, in which the coatings may be applied on distinct substrate and geometries is attractive.

Hipertensión arterial en diferentes edades de la mujer

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José Pacheco-Romero

2010-12-01

Full Text Available La hipertensión se asocia a comorbilidades, como la diabetes mellitus, enfermedad coronaria, apoplejía, enfermedad vascular periférica, falla renal crónica, todo lo cual disminuye la expectativa de vida. La población peruana no se escapa de presentar esta enfermedad de manera similar al resto del mundo, por lo que la hipertensión debe ser debe ser detectada a tiempo en la atención médica diaria, para un manejo oportuno y de beneficio en años de vida con calidad. Se describe la ocurrencia de hipertensión arterial en la mujer, desde la niñez hasta la menopausia, incluyendo la vida reproductiva y la gestación.

Síndrome serotoninérgico en anciano con falla renal crónica tratada con linezolid: reporte de caso

Directory of Open Access Journals (Sweden)

Mauricio Montoya Cañón

2016-04-01

Entre los factores de riesgo para desarrollo de síndrome serotoninérgico se encuentra el uso de linezolid, que en combinación de otros medicamentos con acción serotoninérgica —como los inhibidores selectivos de recaptación de serotonina, el litio, la trazodona, entre otros— se asocia con la presentación de este cuadro. El síndrome serotoninérgico puede ser evitado con una buena educación al personal médico y la modificación de las conductas de prescripción de medicamentos; el pilar del tratamiento se basa en la suspensión de los fármacos que están causando el cuadro y el planteamiento de medidas de soporte.

Religión y capital social en La democracia en América

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de Salas, Jaime

2011-08-01

Full Text Available In this article two ways of understanding religión in Democracy in America are exposed. The second of these is related to Putnam’s idea of social capital. Finally the idea of custom in Tocqueville is related to Ortega’s theory of belief.La intención del artículo consiste en mostrar las dos formas de desarrollar la religión en La democracia de América. La segunda se relaciona con la noción de capital social de Robert Putnam. Asimismo se asocia la doctrina de las costumbres con la noción de creencia en Ortega.

Nuevas formas de llevar una ópera al teatro. Un caso de estudio. La flauta mágica de la compañía 1927 y de Kosky: animación 2d, nuevas tecnologías digitales y estilo vintage

OpenAIRE

Sansone, Vincenzo

2017-01-01

La ópera, un género que a menudo se asocia al pasado, está más viva que nunca. Gracias a la aportación de directores y experimentadores provenientes del teatro, la ópera se ha convertido en uno de los campos por excelencia para la experimentación contemporánea, sobre todo en relación con el uso de nuevas tecnologías. Una verdadera paradoja. Un ejemplo es la puesta en escena de La flauta mágica de Mozart de la Komische Oper de Berlín, concebida y realizada por la compañía británica 1927 y por ...

Identificación e implementación de paquetes tecnológicos en ganadería vacuna de doble propósito. Caso Manabí-Ecuador

OpenAIRE

Yenny Torres; José Rivas; Carmen De Pablos-Heredero; José Perea; Paula Toro-Mujica; Elena Angón; Antón García García

2014-01-01

El avance en los sistemas ganaderos se asocia a la implementación de tecnologías en la producción y a la mejora de sus ingresos. El objetivo del presente estudio fue la identificación e implementación de paquetes te cnológicos y su relación con los resultados productivos en vacuno de doble propósito de la provincia de Manabí, Ecua dor en dos zonas climáticas: el Bosque seco tropical y el húmedo tropical. Se agrupan 25 tecnologías en seis paquetes tecnológicos (PT) seleccionadas mediante una m...

El zinc, micronutriente importante en la salud humana

OpenAIRE

Alicia Velázquez Pérez; Orelvis Pérez Duerto; Juan Rafael Pino de los Reyes

2014-01-01

La importancia biológica del zinc fue admitida por primera vez hace más de un siglo y en la actualidad continúan los estudios que avalan su valor en la nutrición humana. Se ha comprobado que la falta de zinc es bastante frecuente en la población de los países en vías de desarrollo, sobre todo en edades pediátricas, y se asocia en general a malnutrición y deficiencias de otros micronutrientes. El diagnóstico de la deficiencia leve de zinc en el hombre es difícil, ya que produce muchos síntomas...

Infección por metapneumovirus humano en niños hospitalizados por una enfermedad respiratoria aguda grave: Descripción clínico- epidemiológica A human metapneumovirus infection in hospitalized infant patients with severe acute respiratory tract infection: A clinical and epidemiological view

OpenAIRE

JAIME LOZANO C; LETICIA YÁÑEZ P; MICHELANGELO LAPADULA A; MÓNICA LAFOURCADE R; FELIPE BURGOS F; LUIS HERRADA H; ISOLDA BUDNIK O

2009-01-01

El metapneumovirus humano (hMPV) es un virus de reciente diagnóstico. Se asocia con infecciones respiratorias agudas altas y bajas (IRAb). Se efectuó un estudio prospectivo durante dos años con el objetivo de evaluar la tasa de circulación y los hallazgos clínicos asociados a la infección por hMPV en niños hospitalizados por una IRAb grave. Resultados: hMPV fue demostrado en 24 (10,5%) de los 229 niños enrolados. 42% de los pacientes con hMPV eran menores de 12 meses de edad y el 58% tenía al...

Mindfulness: Una propuesta de aplicación en rehabilitación neuropsicológica

OpenAIRE

SARMIENTO-BOLAÑOS, MARÍA JIMENA; GÓMEZ-ACOSTA, ALEXANDER

2013-01-01

A través de la meditación, las personas se hacen conscientes de lo que sucede en su cuerpo y en su mente, aceptando las experiencias presentes tal y como estas son y logrando una mejor comprensión de la verdadera naturaleza de las cosas. Las prácticas de meditación y su inclusión como técnica de intervención han generado gran interés por identificar los mecanismos cerebrales a través de los cuales dichas prácticas actúan. Diferentes estudios plantean que la práctica de la meditación se asocia...

Mindfulness. Uma proposta de aplicação em reabilitação neuropsicológica

OpenAIRE

Sarmiento-Bolaños, María-Jimena; Gómez-Acosta, Alexander

2013-01-01

A través de la meditación, las personas se hacen conscientes de lo que sucede en su cuerpo y en su mente, aceptando las experiencias presentes tal y como éstas son y logrando una mejor comprensión de la verdadera naturaleza de las cosas. Las prácticas de meditación y su inclusión como técnica de intervención han generado gran interés por identificar los mecanismos cerebrales a través de los cuales dichas prácticas actúan. Diferentes estudios plantean que la práctica de la meditación se asocia...

Mindfulness. Una propuesta de aplicación en rehabilitación neuropsicológica

OpenAIRE

María Jimena Sarmiento-Bolaños; Alexander Gómez-Acosta

2013-01-01

A través de la meditación, las personas se hacen conscientes de lo que sucede en su cuerpo y en su mente, aceptando las experiencias presentes tal y como estas son y logrando una mejor comprensión de la verdadera naturaleza de las cosas. Las prácticas de meditación y su inclusión como técnica de intervención han generado gran interés por identificar los mecanismos cerebrales a través de los cuales dichas prácticas actúan. Diferentes estudios plantean que la práctica de la meditación se asocia...

Income Differences on Mexico’s Northern Border: A Perspective on Formal and Informal Employment

Directory of Open Access Journals (Sweden)

Rogelio VARELA LLAMAS

2015-01-01

Full Text Available Con información de la “Encuesta nacional de ocupación y empleo (ENOE” se analizan las diferencias de ingreso entre trabajadores con empleo formal e informal en los estados de la frontera norte de México. La metodología ANOVA sugiere que los ingresos de los trabajadores dif ieren de acuerdo con el tipo de empleo (formal/informal, categoría de ocupación y su efecto de interacción. El modelo logit revela que la probabilidad de tener un empleo informal se asocia a un menor nivel de escolaridad y a un proceso de búsqueda de empleo.

Intervención psicológica con padres: una alternativa en la búsqueda de logros deportivos

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Natalia Guillén

2010-01-01

Full Text Available Es notable la gran influencia que ejercen los padres en el proceso deportivo que llevan sus hijos. Las investigaciones han mostrado la manera en que el comportamiento de los padres se asocia con la elección de la modalidad deportiva, la orientación motivacional e incluso los resultados deportivos. En vista de que la gran mayoría de trabajos se ha enfocado en la intervención psicológica directa con los deportistas, este trabajo pretender ofrecer un marco general de intervención que permita la adquisición de logros deportivos mediante la adquisición de habilidades propias para los padres.

Ciudades portuguesas en el Norte de África : una metamorfosis urbana en los siglos XV y XVI

OpenAIRE

Correia, Jorge

2013-01-01

El asunto que nos proponemos a tratar es amplio y no limitado en el alcance de las líneas que siguen. De hecho, es parte de una investigación más larga que venimos llevando a cabo para el norte de África. Por lo tanto, iremos sólo contextualizar y poner de relieve algunos aspectos que se relacionan con el tema del "encuentro" y/o "colisión" como un proceso y método en la historia de la ciudad. Para la geografía y la cronología en cuestión, este aspecto se asocia inevitablemente à la evolución...

Science.gov (United States)

Zaragoza-Martí, Ana; Sánchez-SanSegundo, Miriam; Ferrer-Cascales, Rosario

2016-11-29

Introducción: el trastorno por atracón o "Binge Eating Disorders" (BED) se caracteriza por el consumo de grandes cantidades de comida en un breve periodo de tiempo acompañado de una sensación de falta de control sobre la ingesta. El BED se relaciona con una alimentación poco equilibrada, contribuyendo a la aparición de diversas patologías. La alimentación y los estilos de vida desempeñan un factor clave en la prevención de estas patologías, siendo la dieta mediterránea (DM) uno de los estándares de la alimentación saludable.Objetivo: analizar la relación entre la DM y el BED en una muestra de estudiantes universitarios.Método: se realizó un estudio descriptivo transversal en una muestra de 120 estudiantes de la Universidad de Alicante. Para establecer la relación entre el patrón de atracón y el grado de adherencia a la DM se determinó el coefi ciente de correlación r de Pearson. Los resultados se expresaron en odds ratios (OR) e intervalo de confi anza (IC) al 95%.Resultados: los sujetos con un patrón de BED presentaron menor adherencia a la DM (OR = 4,03; IC 95%, 1,80-18,69), mayores índices de exceso de peso (OR = 5,31; IC 95%, 1,81-15,64), y vidas más sedentarias (OR = 1,4; IC 95%, 0,52-4,12). El BED correlacionó negativamente con el grado de adherencia DM (r = -0,3, p el patrón de DM se asocia de manera inversa con el riesgo de sufrir trastorno por atracón y además dicho patrón de atracón se asocia significativamente con el riesgo de sufrir exceso de peso en estudiantes universitarios. Son necesarios estudios que confi rmen que la DM reduce el riesgo de sufrir trastorno por atracón.

Iron dysregulation combined with aging prevents sepsis-induced apoptosis.

Science.gov (United States)

Javadi, Pardis; Buchman, Timothy G; Stromberg, Paul E; Turnbull, Isaiah R; Vyas, Dinesh; Hotchkiss, Richard S; Karl, Irene E; Coopersmith, Craig M

2005-09-01

Sepsis, iron loading, and aging cause independent increases in gut epithelial and splenic apoptosis. It is unknown how their combination will affect apoptosis and systemic cytokine levels. Hfe-/- mice (a murine homologue of hemochromatosis) abnormally accumulate iron in their tissues. Aged (24-26 months) or mature (16-18 months) Hfe-/- mice and wild type (WT) littermates were subjected to cecal ligation and puncture (CLP) or sham laparotomy. Intestine, spleen, and blood were harvested 24 h later and assessed for apoptosis and cytokine levels. Gut epithelial and splenic apoptosis were low in both aged septic and sham Hfe-/- mice, regardless of the amount of iron in their diet. Mature septic WT mice had increased apoptosis compared to age-matched sham WT mice. Mature septic Hfe-/- mice had similar levels of intestinal cell death to age-matched septic WT mice but higher levels of splenic apoptosis. Apoptosis was significantly lower in septic aged Hfe-/- mice than septic mature Hfe-/- animals. Interleukin-6 was elevated in septic aged Hfe-/- mice compared to sham mice. Although sepsis, chronic iron dysregulation, and aging each increase gut and splenic apoptosis, their combination yields cell death levels similar to sham animals despite the fact that aged Hfe-/- mice are able to mount an inflammatory response following CLP and mature Hfe-/- mice have elevated sepsis-induced apoptosis. Combining sepsis with two risk factors that ordinarily increase cell death and increase mortality in CLP yields an apoptotic response that could not have been predicted based upon each element in isolation.

Association Studies of HFE C282Y and H63D Variants with Oral Cancer Risk and Iron Homeostasis Among Whites and Blacks

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Nathan R. Jones

2015-12-01

Full Text Available Background: Polymorphisms in the hemochromatosis (HFE gene are associated with excessive iron absorption from the diet, and pro-oxidant effects of iron accumulation are thought to be a risk factor for several types of cancer. Methods: The C282Y (rs1800562 and H63D (rs1799945 polymorphisms were genotyped in 301 oral cancer cases and 437 controls and analyzed in relation to oral cancer risk, and serum iron biomarker levels from a subset of 130 subjects. Results: Individuals with the C282Y allele had lower total iron binding capacity (TIBC (321.2 ± 37.2 µg/dL vs. 397.7 ± 89.0 µg/dL, p = 0.007 and higher percent transferrin saturation (22.0 ± 8.7 vs. 35.6 ± 22.9, p = 0.023 than wild type individuals. Iron and ferritin levels approached significantly higher levels for the C282Y allele (p = 0.0632 and p = 0.0588, respectively. Conclusions: Iron biomarker levels were elevated by the C282Y allele, but neither (rs1800562 nor (rs1799945 was associated with oral cancer risk in blacks and whites.

State of science: human factors and ergonomics in healthcare.

Science.gov (United States)

Hignett, Sue; Carayon, Pascale; Buckle, Peter; Catchpole, Ken

2013-01-01

The past decade has seen an increase in the application of human factors and ergonomics (HFE) techniques to healthcare delivery in a broad range of contexts (domains, locations and environments). This paper provides a state of science commentary using four examples of HFE in healthcare to review and discuss analytical and implementation challenges and to identify future issues for HFE. The examples include two domain areas (occupational ergonomics and surgical safety) to illustrate a traditional application of HFE and the area that has probably received the most research attention. The other two examples show how systems and design have been addressed in healthcare with theoretical approaches for organisational and socio-technical systems and design for patient safety. Future opportunities are identified to develop and embed HFE systems thinking in healthcare including new theoretical models and long-term collaborative partnerships. HFE can contribute to systems and design initiatives for both patients and clinicians to improve everyday performance and safety, and help to reduce and control spiralling healthcare costs. There has been an increase in the application of HFE techniques to healthcare delivery in the past 10 years. This paper provides a state of science commentary using four illustrative examples (occupational ergonomics, design for patient safety, surgical safety and organisational and socio-technical systems) to review and discuss analytical and implementation challenges and identify future issues for HFE.

Expression and crystallization of SeDsbA, SeDsbL and SeSrgA from Salmonella enterica serovar Typhimurium

International Nuclear Information System (INIS)

Jarrott, R.; Shouldice, S. R.; Gunčar, G.; Totsika, M.; Schembri, M. A.; Heras, B.

2010-01-01

The cloning, purification, crystallization and preliminary crystallographic studies of three DsbA-like proteins present in S. enterica serovar Typhimurium, SeDsbA, SeDsbL and SeSrgA, are reported. Pathogens require protein-folding enzymes to produce functional virulence determinants. These foldases include the Dsb family of proteins, which catalyze oxidative folding in bacteria. Bacterial disulfide catalytic processes have been well characterized in Escherichia coli K-12 and these mechanisms have been extrapolated to other organisms. However, recent research indicates that the K-12 complement of Dsb proteins is not common to all bacteria. Importantly, many pathogenic bacteria have an extended arsenal of Dsb catalysts that is linked to their virulence. To help to elucidate the process of oxidative folding in pathogens containing a wide repertoire of Dsb proteins, Salmonella enterica serovar Typhimurium has been focused on. This Gram-negative bacterium contains three DsbA proteins: SeDsbA, SeDsbL and SeSrgA. Here, the expression, purification, crystallization and preliminary diffraction analysis of these three proteins are reported. SeDsbA, SeDsbL and SeSrgA crystals diffracted to resolution limits of 1.55, 1.57 and 2.6 Å and belonged to space groups P2 1 , P2 1 2 1 2 and C2, respectively

What do human factors and ergonomics professionals value in research publications? Re-examining the research-practice gap.

Science.gov (United States)

Chung, Amy Z Q; Williamson, Ann; Shorrock, Steven T

2014-01-01

The research-practice gap is of concern in human factors/ergonomics (HF/E) as there is a belief that HF/E research may not be making an impact on practice in the 'real world'. A potential issue is what researchers and practitioners perceive as important in HF/E journal articles as a primary means of conveying research findings to practitioners. This study examined the characteristics that make scientific journal articles appeal to HF/E researchers and practitioners using a web-based survey. HF/E researchers and practitioners were more similar than expected in judgements of important attributes and the selection of articles. Both practitioners and researchers considered practical significance to be more important than theoretical significance, in direct contrast to professionals from a related discipline--psychology. Well-written articles were appreciated across disciplines. The results signal a strong interest in practical applications in HF/E, but a relative lack of focus on development of theories that should be the basis for practical applications.

Human Factors Engineering: Current Practices and Development Needs in Finland

Energy Technology Data Exchange (ETDEWEB)

Savioja, Paula; Norros, Leena; Liinasuo, Marja; Laarni, Jari [VTT Technical Research Centre of Finland, Finland (Finland)

2011-08-15

This paper describes initial findings from a study concerning the practices and development needs of Human Factors Engineering (HFE) in Finland. HFE is increasing in importance as the Radiation and Nuclear Safety Authority Finland (STUK) is renewing the regulatory guidelines and the intention is to include requirements concerning HFE. The motivation for the paper is to discover how HFE is conducted currently in order to envision what should be aimed at when modifying requirements for design practices. In an interview with STUK it was discovered that current HFE practices encompass mainly activities related to control room modifications and as such namely verification and validation of new designs. The adoption of the entire HFE process in design and modification projects requires changes that include better integration of technical and Human Factors Engineering approaches. Boundary objects that mediate between different design disciplines are needed in order to enforce the stronger integration. Concept of operations (CONOPS) is suggested as a such boundary object.

Analysis of high-frequency energy in long-term average spectra of singing, speech, and voiceless fricatives.

Science.gov (United States)

Monson, Brian B; Lotto, Andrew J; Story, Brad H

2012-09-01

The human singing and speech spectrum includes energy above 5 kHz. To begin an in-depth exploration of this high-frequency energy (HFE), a database of anechoic high-fidelity recordings of singers and talkers was created and analyzed. Third-octave band analysis from the long-term average spectra showed that production level (soft vs normal vs loud), production mode (singing vs speech), and phoneme (for voiceless fricatives) all significantly affected HFE characteristics. Specifically, increased production level caused an increase in absolute HFE level, but a decrease in relative HFE level. Singing exhibited higher levels of HFE than speech in the soft and normal conditions, but not in the loud condition. Third-octave band levels distinguished phoneme class of voiceless fricatives. Female HFE levels were significantly greater than male levels only above 11 kHz. This information is pertinent to various areas of acoustics, including vocal tract modeling, voice synthesis, augmentative hearing technology (hearing aids and cochlear implants), and training/therapy for singing and speech.

CuInSe2 nano-crystallite reaction kinetics using solid state reaction from Cu2Se and In2Se3 powders

International Nuclear Information System (INIS)

Hsiang, Hsing-I; Lu, Li-Hsin; Chang, Yu-Lun; Ray, Dahtong; Yen, Fu-Su

2011-01-01

Highlights: → CuInSe 2 phase increased gradually accompanied with a decrease in γ-In 2 Se 3 and no intermediate phase during calcination. → CuInSe 2 formation from Cu 2 Se and In 2 Se 3 powders follows a one-dimensional diffusion-controlled reaction with apparent activation energy of about 122.5 kJ/mol. → The solid reaction kinetics may be dominated by the diffusion of In 3+ ions. - Abstract: The reaction mechanism and CuInSe 2 formation kinetics using a solid state reaction from Cu 2 Se and In 2 Se 3 powders synthesized using a heating up process were investigated using X-ray diffractomy (XRD) and transmission electron microscopy (TEM). It was observed that the CuInSe 2 phase increased gradually, accompanied with a decrease in γ-In 2 Se 3 with no intermediate phase as the calcination temperature and soaking time were increased. The reaction kinetics was analyzed using the Avrami and polynomial kinetic model, suggesting that CuInSe 2 formation from Cu 2 Se and In 2 Se 3 powders follows a diffusion-controlled reaction with an apparent activation energy of about 122.5-182.3 kJ/mol. Cu 2 Se and In 2 Se 3 phases react and directly transform into CIS without the occurrence of any intermediate phase and the size of the newly formed CuInSe 2 crystallites was close to that of the Cu 2 Se reactant particle based on the TEM results, which indicated that the solid reaction kinetics may be dominated by the diffusion of In 3+ ions.

La influencia de los padres sobre el consumo de alcohol y tabaco y otros hábitos de los adolescentes de Palma de Mallorca en 2003

Directory of Open Access Journals (Sweden)

Francisco Manuel Kovacs

2008-01-01

Full Text Available Fundamento. El consumo de alcohol y tabaco es frecuente entre los adolescentes. El objetivo de este estudio fue determinar la influencia de los hábitos de los padres en los de sus hijos. Métodos. Se estudió a los adolescentes de 13 a 15 años de la isla de Mallorca y a sus padres. Mediante métodos previamente validados se recabó su nivel socioeconómico, sus hábitos (ingesta de alcohol, tabaquismo, práctica de deportes y consumo de televisión, y el rendimiento académico de los adolescentes. Resultados. Participaron 4.019 adolescentes y 7.359 padres. Un bajo nivel socioeconómico se asoció con un mayor riesgo de que los adolescentes fumaran (OR=3,86, IC 95%: 2,30-6,48; p=0,000, bebieran alcohol (OR=1,88; 95% IC: 1,40- 2,54; p=0,000, suspendieran alguna asignatura (OR=6,37, IC 95%: 4,23-9,61; p=0,000, vieran > 2 horas diarias de televisión (OR=1,97;95%IC: 1,69-2,29; p=0,000, y no practicaran deporte (OR=0,55, IC 95%: 0,38-0,80; p=0,001. Además, en el riesgo de que fumaran influyó que la madre bebiera (OR 1,76 IC95% 1,24-1,51; p=0,002, en el de que suspendieran los hijos (no las hijas que los padres fumaran (OR 1,89 IC95% 1,33- 2,68; p=0,000, y los correspondientes hábitos en los padres aumentaron la probabilidad de que los adolescentes bebieran alcohol (OR 1,91 IC95% 1,43-2,51; p=0,000, vieran más de 2 horas diarias la televisión (OR 1,97 IC95% 1,68-2,29; p=0,000 e hicieran deporte (OR 6,67 IC95% 2,57-14,96; p=0,000. Conclusiones. Un bajo nivel socioeconómico se asocia a un mayor riesgo de que los adolescentes españoles fumen, beban alcohol, suspendan, vean más televisión y no practiquen deporte. Además, el que la madre beba se asocia a un mayor riesgo de que sus hijos fumen y beban, y el que ambos padres beban se asocia a un mayor riesgo de que sus hijos lo hagan. La práctica de deportes y el tiempo que pasan ante el televisor los padres influyen en los hábitos correspondientes por parte de sus hijos, pero no influyen en

78 FR 77729 - Biweekly Notice: Applications and Amendments to Facility Operating Licenses and Combined Licenses...

Science.gov (United States)

2013-12-24

... existing batteries. Battery circuit coordination is not adversely affected by the addition of the new... Factors Engineering (HFE) Reports (prepared by Westinghouse and the NRC reviewed these reports as part of...: HFE Integrated System Validation (APP-OCS-GEH-320) (LAR 13-001) HFE Design Verification Plan (APP-OCS...

Controllable size reduction of CdSe nanowires through the intermediate formation of Se-coated CdSe nanowires using acid and thermal treatment

Energy Technology Data Exchange (ETDEWEB)

Lam, N S [Department of Physics, Chinese University of Hong Kong, Hong Kong (China); Wong, K W [Department of Physics, Chinese University of Hong Kong, Hong Kong (China); Li, Q [Department of Physics, Chinese University of Hong Kong, Hong Kong (China); Zheng, Z [Department of Physics, Chinese University of Hong Kong, Hong Kong (China); Lau, W M [Surface Science Western, University of Western Ontario, London, ON, N6A 5B7 (Canada)

2007-10-17

Thinning of CdSe nanowires (NWs) with controllable size was achieved by a simple acid treatment and subsequent annealing on thick CdSe NWs synthesized from vapour phase growth. During acid treatment, not only the undesired impurities such as native oxides of Cd and Se could be etched, but surface reactions of CdSe NWs were also observed, resulting in the formation of a layer of elemental Se around a thinner CdSe core. As a result, a heterostructure of Se - CdSe nanostructure formed after acid treatment of CdSe NWs. Upon thermal annealing, the Se shell was effectively removed and thinned stoichiometric single-crystalline CdSe NWs could be obtained. It was observed that NWs could be thinned by up to {approx}60% in diameter by acid treatment and subsequent Se thermal desorption. The degree of thinning was controllable by adjusting the duration of acid treatment. The success of the thinning of CdSe NWs by simple acid treatment and the annealing process reported here opens a new processing route for obtaining stoichiometric CdSe NWs with controllable size reduction and improved aspect ratio. This can undoubtedly broadly improve the range of applications of 1D CdSe nanostructures and allow more exploration of their uni-directional properties. A correction was made to the last paragraph of section 3 on 18 September 2007. The corrected electronic version is identical to the print version.

Controllable size reduction of CdSe nanowires through the intermediate formation of Se-coated CdSe nanowires using acid and thermal treatment

International Nuclear Information System (INIS)

Lam, N S; Wong, K W; Li, Q; Zheng, Z; Lau, W M

2007-01-01

Thinning of CdSe nanowires (NWs) with controllable size was achieved by a simple acid treatment and subsequent annealing on thick CdSe NWs synthesized from vapour phase growth. During acid treatment, not only the undesired impurities such as native oxides of Cd and Se could be etched, but surface reactions of CdSe NWs were also observed, resulting in the formation of a layer of elemental Se around a thinner CdSe core. As a result, a heterostructure of Se - CdSe nanostructure formed after acid treatment of CdSe NWs. Upon thermal annealing, the Se shell was effectively removed and thinned stoichiometric single-crystalline CdSe NWs could be obtained. It was observed that NWs could be thinned by up to ∼60% in diameter by acid treatment and subsequent Se thermal desorption. The degree of thinning was controllable by adjusting the duration of acid treatment. The success of the thinning of CdSe NWs by simple acid treatment and the annealing process reported here opens a new processing route for obtaining stoichiometric CdSe NWs with controllable size reduction and improved aspect ratio. This can undoubtedly broadly improve the range of applications of 1D CdSe nanostructures and allow more exploration of their uni-directional properties. A correction was made to the last paragraph of section 3 on 18 September 2007. The corrected electronic version is identical to the print version

Operating experience review in development of SMART MMIS

International Nuclear Information System (INIS)

Suh, S. M.; Jang, G. S.; Lee, J. G.; Park, G. O.; Ko, J. H.

2004-01-01

We have developed HFE(Human Factors Engineering) program plan for the purpose of implementing man-machine interface system in SMART plant systematically. Elements of the plan are compatible to those of NUREG-0711, Rev.1, and OER(Operating Experience Review) is one of them. The main purpose of conducting an OER as part of HFE review is to identify HFE-related safety issues. If identified, design alternatives are carefully reviewed and selected as the way of resolution for those issues. The performing model of OER is described in this paper, showing a series of works must be done to identify and resolve HFE-related issues within the scope of SMART HFE works. Then two key issues and design alternatives resolving them are presented for examples

Benefits of oxygen in CuInSe{sub 2} and CuGaSe{sub 2} containing Se-rich grain boundaries

Energy Technology Data Exchange (ETDEWEB)

Feng, Chunbao, E-mail: chunbaofeng@126.com [Department of Mathematics and Physics, Chongqing University of Posts and Telecommunications, Chongqing, 400065 (China); Luo, Min; Li, Bolin; Li, Dengfeng [Department of Mathematics and Physics, Chongqing University of Posts and Telecommunications, Chongqing, 400065 (China); Nie, Jinlan [Department of Applied Physics, University of Electronic Science and Technology of China, Chengdu, 610054 (China); Dong, Huining [Department of Mathematics and Physics, Chongqing University of Posts and Telecommunications, Chongqing, 400065 (China)

2014-05-01

Using density functional theory calculation, we show that oxygen (O) exhibits an interesting effect in CuInSe{sub 2} and CuGaSe{sub 2}. The Se atoms with dangling bonds in a Se-rich Σ3 (114) grain boundary (GB) create deep gap states due to strong interaction between Se atoms. However, when such a Se atom is substituted by an O atom, the deep gap states can be shifted into valence band, making the site no longer a harmful non-radiative recombination center. We find that O atoms prefer energetically to substitute these Se atoms and induce significant lattice relaxation due to their smaller atomic size and stronger electronegativity, which effectively reduces the anion–anion interaction. Consequently, the deep gap states are shifted to lower energy regions close or even below the top of the valence band.

Relaciones Interpersonales y Sintomatología Ansiosa en Niños Víctimas de Maltrato Parental

Directory of Open Access Journals (Sweden)

Marisela Ramírez

2003-03-01

Full Text Available El artículo describe cómo la vivencia de maltrato al interior del hogar se asocia a niveles altos de sintomatología ansiosa y a relaciones interpersonales disfuncionales al interior del colegio.Se comparan las relaciones interpersonales en el colegio y los niveles de sintomatología ansiosa en un grupo de 30 niños maltratados por sus padres y un grupo pareado de 30 niños no maltratados. Los maltratados presentan mayor ansiedad, retraimiento social y pasan desapercibidos en situaciones sociales como el estudio y el juego. Sin embargo, son escogidos para guardar un secreto. Se discute como esta dinámica al interior del colegio reforzaría su sintomatología ansiosa y el retraimiento social; que frecuentemente se asocian a las experiencias de maltrato en el hogar.

Dolor músculo-esquelético en pacientes con enfermedad renal crónica

Directory of Open Access Journals (Sweden)

Francisco Caravaca

2016-07-01

Conclusiones: El DMEC es muy prevalente en pacientes con ERC avanzada, y se asocia con otros síntomas comunes de la uremia crónica. Al igual que en la población general, características como sexo femenino, edad avanzada, obesidad y comorbilidad están más frecuentemente asociados al DMEC. La elevación de los marcadores de inflamación asociada al DMEC podría ser un hallazgo relevante para explicar su patogenia.

Hábitos alimentarios en niños celiacos

OpenAIRE

Martín Arroyo, Sheila

2016-01-01

La Enfermedad Celiaca (EC) es una enfermedad de origen autoinmune provocada por la ingesta de gluten en individuos genéticamente susceptibles cuyo único tratamiento seguro y eficaz es la Dieta Sin Gluten (DSG). Estudiar los hábitos alimentarios de los pacientes en edad pediátrica diagnosticados de EC y compararlos con los de un grupo control pareado por edad y sexo. El objetivo secundario es observar si ambos grupos se adecuan a las recomendaciones nutricionales de la Asocia...

ATMEA1 Nuclear Power Plant. Overview of the HF engineering program

International Nuclear Information System (INIS)

Rivere, Cyril; Mashio, Kenji; Martinez-Pellegrini, Diego

2015-01-01

ATMEA, a joint-venture between AREVA and Mitsubishi Heavy Industries has developed the ATMEA1 Pressurized Water Reactor (PWR) Nuclear Island (NI), leveraging both of its shareholders’ proficient technologies, innovations and experiences. The scope of the ATMEA1 PWR development covers the complete scope of engineering works necessary to develop a standard product. As a recently emergent discipline in the field of nuclear plant engineering, Human Factor Engineering (HFE) is one of the challenges which has to be integrated within new plant development process. At early design stages of ATMEA1 development, ATMEA has defined and implemented an extensive NUREG-based HFE program, encompassing HFE Preliminary Analyses, Human-Systems Interfaces (HSI) Design and Verification and Validation (V and V) activities. The HFE Preliminary Analyses are defined through Operating Experience Review (OER), Functional Requirement Analysis and Function Allocation (FRA/FA) and Task Analysis (TA). Human-System Interface (HSI) Design and related V and V activities are based on Control Center, Control Rooms and Human-Machine Interfaces (HMIs). All these steps are implemented within the ATMEA Project through a structured generic documentation basis by a HFE team composed of HF specialists from both AREVA and MHI and managed by ATMEA. ATMEA1 development project aims to develop flexible and robust design and process which can be easily adapted to be compliant to any regulations over the world. U.S. regulatory guidelines related to HFE (e.g. ref. [1] and ref. [2]) were applied as a basis for this project. This paper presents the overall ATMEA1 HFE program content and the related process used to favor its implementation within the Project; through the collaboration between MHI and AREVA under ATMEA lead. A special focus is made on the HFE team composition, roles and responsibilities, the management of interfaces with the relevant engineering disciplines and the tools used to support the HFE

Alternative syntheses of [73,75Se]selenoethers exemplified for homocysteine[73,75Se]selenolactone

International Nuclear Information System (INIS)

Ermert, J.; Blum, T.; Hamacher, K.; Coenen, H.H.

2001-01-01

The present work describes two radiosynthetic pathways to prepare homocysteine[ 75 Se]selenolactone 1 starting from n.c.a. [ 75 Se]selenite 2. It was achieved either by alkylation reaction of n.c.a. methyl[ 75 Se]selenide 4 or by hydrolysis of alkylated 1,3-dicyclohexyl[ 75 Se]selenourea 11. N.c.a. methyl[ 75 Se]selenide 4 is available using sulfur as non-isotopic carrier. However, the radiochemical yield of the substitution of 2-tert.-butoxycarbonylamino-4-bromobutyric acid ethylester 5 with n.c.a. methyl-[ 75 Se]selenide is only in the range of 15%-20%. Birch reduction of protected n.c.a. [ 75 Se]selenomethionine 6 formed leads to a RCY of 5%-10% homocysteine[ 75 Se]selenolactone 1. Alternatively, the synthesis of homocysteine[ 75 Se]selenolactone 1 is possible by hydrolysis of the corresponding [ 75 Se]selenouronium salt 11 available by addition of 2-tert.-butoxycarbonylamino-4-bromobutyric acid ethylester 5 to 1,3-dicyclohexyl[ 75 Se]selenourea 10. A method was developed for the synthesis of 1,3-dicyclohexyl[ 75 Se]selenourea 10 by addition of c.a. [ 75 Se]SeH 2 to 1,3-dicyclohexylcarbodiimide, which leads to 20%-30% RCY of c.a. homocysteine[ 75 Se]selenolactone 1. (orig.)

The determination of Se content in Se egg by NAA in MNSR

International Nuclear Information System (INIS)

Wang Ke; Hou Xiaolin

1994-01-01

The selenium contents in the yolk, albumin and shell of the egg which was laid by layer hen fed with various Se concentrations are determined by thermal neutron activation analysis with a nuclear reaction 78 Se(n, γ) 77 Se m on the miniature neutron source reactor (MNSR). The results show that the more the selenium added to the feed, the higher the Se content in the egg and that in the egg constituents, the highest Se content is in the egg yolk and the lowest in the egg albumin

MARCADORES MOLECULARES ASOCIADOS CON RESISTENCIA A LA ENFERMEDAD PUNTA MORADA EN PAPA

Directory of Open Access Journals (Sweden)

Ferm\\u00EDn Orona-Castro

2009-01-01

Full Text Available El objetivo de este trabajo fue identificar marcadores DNA Polimórfico Amplificado al Azar (RAPDs y Secuencias Simples Repetidas (SSR s también conocidos como Mi crosatélites asocia dos con la resistencia al daño causado por fitoplasmas en papa. Se evaluó la severidad de la punta morada de la papa (PMP y la apa rición de color pardo en el tubérculo, así como también se realizaron análisis moleculares en varie dades y líneas avanzadas de papa . El estudio se realizó en el laboratorio de biotecnología de la Facultad de Cie ncia s Biológicas de la Universidad Autónoma de Nuevo León - Instituto Na cional de Investigaciones Forestales Agrícolas y Pecuarias (INI FAP, México en el 2003 y 2004. Las técnicas utilizadas fueron RAPDs y SSRs también conocido microsatélites. Tres genotip os mostraron resistencia a la apa rición del color pardo deltubérculo, mie ntras que del análisis molecular seis materia les formaron un grupo que incluyó los genotip os con valores de daño mínimos (entre uno y tres de la escala. Los genotip os restantes formaron dos grupos con presencia de color pardo en el tubérculo mayor (entre cinco y siete. Se identificaron marcadores moleculares posiblemente asocia dos con tolerancia a la coloración parda del tubérculo. En el análisis de componentes principa les y el dendograma generado los materia les que presentaron menor severidad de daño, quedaron incluidos en un mismo grupo, mie ntras que materia les con mayor severidad de daño quedaron en un grupo diferente

Luminescence spectra of CdSe/ZnSe double layers of quantum dots

Energy Technology Data Exchange (ETDEWEB)

Reznitsky, Alexander; Permogorov, Sergei; Korenev, Vladimir V.; Sedova, Irina; Sorokin, Sergey; Sitnikova, Alla; Ivanov, Sergei [A.F. Ioffe Physico-Technical Institute, Polytekhnicheskaya 26, 194021 St. Petersburg (Russian Federation); Klochikhin, Albert [B.P. Konstantinov Nuclear Physics Institute, St. Petersburg (Russian Federation)

2009-12-15

We have studied the emission spectra and structural properties of double CdSe/ZnSe quantum dot (QD) sheet structures grown by molecular beam epitaxy in order to elucidate the mechanisms of the electronic and strain field interaction between the QD planes. The thickness of the ZnSe barrier separating the CdSe sheets was in the range of 10-60 monolayers (ML) in the set of samples studied. We have found that coupling between dots in adjacent layers becomes relatively strong in CdSe/ZnSe double layers structures with 25-27 ML barrier, while it is rather weak when the barrier thickness exceeds 30 ML. (copyright 2009 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

Linfoma de Burkitt primario de la cavidad oral en una paciente con sida. Reporte de un caso y revisión de la literatura

Directory of Open Access Journals (Sweden)

Marcelo Corti

2015-01-01

Full Text Available Los linfomas no Hodgkin (LNH son un grupo heterogéneo de enfermedades linfoproliferativas con elevada prevalencia en pacientes infectados por el virus de la inmunodeficiencia humana (VIH. La inmunodeficiencia asociada al sida predispone al desarrollo de LNH, incluyendo el linfoma de Burkitt (LB. El LB es un subtipo infrecuente y agresivo de LNH con elevada frecuencia en pacientes con sida. Se asocia a una alta tasa de replicación celular (determinada por el índice Ki67 y con alta frecuencia de compromiso extranodal como forma de presentación clínica de la neoplasia. Se presenta una paciente con sida que desarrolló un LB primario de la cavidad oral y se realiza una revisión de la literatura sobre el tema.

La actividad periodística entre la ley, la ética y la responsabilidad social. Un diagnóstico de las noticias asociadas al delito

Directory of Open Access Journals (Sweden)

Flavia Ivana Ragagnin

2007-01-01

Full Text Available Aún se mantiene en discusión cuál es el límite claro entre la libertad de empresa, donde en primera instancia se asocia el objetivo del lucro, frente a la libertad que asiste a las empresas de carácter periodístico, donde su función ha de centrarse en el servicio social para defender la libertad de expresión y el derecho a la información. Los intereses de sintonía, que generalmente redundan en propósitos rentables, obvian en gran medida los fundamentos éticos a favor de la audiencia y, en los casos puntuales de noticias relacionadas con delitos, se descubren una discriminación y una estigmatización la mayoría de las veces gratuitas.

Analysis of high-frequency energy in long-term average spectra of singing, speech, and voiceless fricatives

Science.gov (United States)

Monson, Brian B.; Lotto, Andrew J.; Story, Brad H.

2012-01-01

The human singing and speech spectrum includes energy above 5 kHz. To begin an in-depth exploration of this high-frequency energy (HFE), a database of anechoic high-fidelity recordings of singers and talkers was created and analyzed. Third-octave band analysis from the long-term average spectra showed that production level (soft vs normal vs loud), production mode (singing vs speech), and phoneme (for voiceless fricatives) all significantly affected HFE characteristics. Specifically, increased production level caused an increase in absolute HFE level, but a decrease in relative HFE level. Singing exhibited higher levels of HFE than speech in the soft and normal conditions, but not in the loud condition. Third-octave band levels distinguished phoneme class of voiceless fricatives. Female HFE levels were significantly greater than male levels only above 11 kHz. This information is pertinent to various areas of acoustics, including vocal tract modeling, voice synthesis, augmentative hearing technology (hearing aids and cochlear implants), and training/therapy for singing and speech. PMID:22978902

An improvement of the applicability of human factors guidelines for coping with human factors issues in nuclear power plants

International Nuclear Information System (INIS)

Lee, Y. H.; Lee, J. Y.

2003-01-01

Human factors have been well known as one of the key factors to the system effectiveness as well as the efficiency and safety of nuclear power plants(NPPs). Human factors engineering(HFE) are included in periodic safety review(PSR) on the existing NPPs and the formal safety assessment for the new ones. However, HFE for NPPs is still neither popular in practice nor concrete in methodology. Especially, the human factors guidelines, which are the most frequent form of human factors engineering in practice, reveal the limitations in their applications. We discuss the limitations and their casual factors found in human factors guidelines in order to lesson the workload of HFE practitioners and to improve the applicability of human factors guidelines. According to the purposes and the phases of HFE for NPPs, more selective items and specified criteria should be prepared carefully in the human factors guidelines for the each HFE applications in practice. These finding on the human factors guidelines can be transferred to the other HFE application field, such as military, aviation, telecommunication, HCI, and product safety

Hopping conduction in gamma-irradiated InSe and InSe:Sn single crystals

International Nuclear Information System (INIS)

MUSTAFAEVA, S.N.; ISMAILOV, A.A.; ASADOV, M.M.

2010-01-01

Full text : The semiconductive InSe layer compound is characterized by a strong covalent bond inside the layers and a weak Van der Waals bonding between them. It was shown that across the layers of InSe single crystals at low temperatures (T ≤ 200 K) at direct current (dc) hopping conduction through localized states near the Fermi level takes place. The results of dc-conductivity of gamma-irradiated p-InSe and n-InSe : Sn layer single crystals have been presented in this work. ρ-InSe single crystal specimens grown by the Bridgman method were used in the experiments. Plates of the crystals under study were obtained by cleaving along the layers of single crystal ingots. The single-crystal InSe samples for electric measurements had the form of planar capacitors normal to the C axis of the crystals, with silver-paste electrodes. The thickness of the InSe samples was 300 mkm. Co 60 serves as the source of irradiation with energy of gamma-quantum equal to 1.3 MeV. The electric properties of non-irradiated and gamma-irradiated InSe crystals were measured under the same conditions. It is revealed that InSe and InSe : Sn (0.2 and 0.4 mole percent Sn) single crystals exhibit a variable range hopping conduction along a normal to their natural layers at temperatures T≤200 K in a dc electric field. From experimental data the parameters of localized states of p-InSe and n-InSe : Sn were calculated before and after gamma-irradiation. It is revealed that gamma-irradiation of p-InSe and n-InSe : Sn (0.2 and 0.4 mole percent Sn) single crystals leads to significant change of localized states parameters. After gamma-irradiation the density of states near the Fermi level increased, but their energy spread and the average jump distance decreased. The concentrations of radiated defects were estimated in p-InSe (5.18*10 1 7 sm - 3) and n-InSe : Sn (2.5*10 1 7 - 2.7*10 1 8 sm - 3) single crystals. The present results demonstrate that gamma-irradiation offers the possibility of tuning

Structure of Se-rich As-Se glasses by high-resolution x-ray photoelectron spectroscopy

International Nuclear Information System (INIS)

Golovchak, R.; Kovalskiy, A.; Miller, A. C.; Jain, H.; Shpotyuk, O.

2007-01-01

To establish the validity of various proposed structural models, we have investigated the structure of the binary As x Se 100-x chalcogenide glass family (x≤40) by high-resolution x-ray photoelectron spectroscopy. From the composition dependence of the valence band, the contributions to the density of states from the 4p lone pair electrons of Se and the 4p bonding states and 4s electrons of Se and As are identified in the top part of the band. The analysis of Se 3d and As 3d core-level spectra supports the so-called chain crossing model for the atomic structure of Se-rich As x Se 100-x bulk glasses. The results also indicate small deviations (∼3-8%) from this model, especially for glass compositions with short Se chains (25 40 Se 60 and of Se-Se-Se fragments in a glass with composition x=30 is established

Phase diagram of SnTe-CdSe cross-section of SnTe+CdSe reversible SnSe+CdTe ternary reciprocal system

International Nuclear Information System (INIS)

Dubrovin, I.V.; Budennaya, L.D.; Mizetskaya, I.B.; Sharkina, Eh.V.

1986-01-01

Phase equilibrium diagram of SnTe-CdSe cross-section of Sn, Cd long Te, Se ternary reciprocal system is investigated using the methods of differential thermal, X-ray phase, and microstructural analyses. Maximum length of solid solutions on the base of SnTe corresponds to approximately 14 mol.% at 1050 K and approximately 3 mol.% of CdSe at 670 K. Region of solid solutions on the base of CdSe corresponds to less than 1 mol.% of SnTe at room temperature. SnTe-CdSe cross-section is not a quasibinar one. Equilibrium is shifted to the left in the SnTe+CdSe reversible SnSe+CdTe reciprocal system

Síndrome de Prader Willi: Presentación clínica de dos pacientes y revisión de la literatura Prader-Willi syndrome: Clinical report of two patients and literature review

Directory of Open Access Journals (Sweden)

Nuris Rodríguez Vargas

2006-03-01

Full Text Available El síndrome de Prader Willi es una afección de niños y jóvenes caracterizada por obesidad, baja talla, oligofrenia, llanto débil o gemido, hipoplasia de los escrotos, testículos no descendidos, entre otros. En la pubertad se asocia a un desarrollo demorado e incompleto y a la aparición de diabetes mellitus y elevada excreción de gonadotropina. Presentamos en este trabajo a dos pacientes que cumplen estos criterios clínicos y que fueron estudiados en el Policlínico Docente «19 de Abril». Se realiza una breve revisión bibliográfica del síndrome.

Los retos para la calidad del quehacer de la universidad.

Directory of Open Access Journals (Sweden)

Juan Bautista Arríen.

1998-03-01

Full Text Available La universidad en proceso de cambio La educación superior en general y en la universidad más en particular, han vivido en la última mitad de este siglo una vasta transformación que se asocia principalmente a cuatro procesos: la multiplicación y diferenciación de las instituciones, la creciente participación del sector privado, la ampliación y el aumento del número y variedad de los graduados. Sin embargo, la verdadera revolución experimentada por la educación superior latinoamericana y centroamericana no siempre a desembocado, donde necesitábamos, sobre todo si se consideran los desafíos que tenemos por delante.

Human factors/ergonomics as a systems discipline? "The human use of human beings" revisited

DEFF Research Database (Denmark)

Hollnagel, Erik

2014-01-01

Discussions of the possible future of Human factors/ergonomics (HFE) usually take the past for granted in the sense that the future of HFE is assumed to be more of the same. This paper argues that the nature of work in the early 2010s is so different from the nature of work when HFE was formulated...

THE EFFECT OF HAEMOCHROMATOSIS MUTATION ON IRON OVERLOAD IN THALASSAEMIA MAJOR PATIENTS

Directory of Open Access Journals (Sweden)

Tapas Ranjan Behera

2016-11-01

Full Text Available BACKGROUND Haemochromatosis is a genetic form of iron overload due to a defective HFE gene. Secondary iron overload is the main complication in transfusion-dependent thalassaemia major patients. This study aims at evaluating the degree of iron overload in β-thalassaemia major patients with and without HFE mutations (C282Y, H63D and S65C. MATERIALS AND METHODS A descriptive observational study was conducted including fifty diagnosed -thalassaemia major cases. Detailed clinical history and iron profile was estimated. DNA analysis by PCR-RFLP method for HFE gene mutations was performed. RESULTS After DNA analysis of all the thalassaemia major cases, two groups were identified, one with HFE gene mutation and other without HFE gene mutation. Iron profile of both the groups (with and without HFE gene mutation was estimated and compared. Only H63D mutation (out of three HFE gene mutations was detected in 16% cases (8 out of 50 cases, which comprised the group with mutation. Comparison of iron parameters between two groups (with and without HFE gene mutation showed significant difference in percent transferrin saturation (p=0.02, while other iron parameters (serum iron and serum ferritin did not show significant difference. CONCLUSION No significant difference between serum ferritin values (a marker of iron overload of groups with and without mutation (mean ferritin level 4641±2166 ng/mL and 4170±2461 ng/mL, respectively was found (p=0.61, in a patient population in whom transfusion protocol and proper chelation regimen was followed.

SIMULATED HUMAN ERROR PROBABILITY AND ITS APPLICATION TO DYNAMIC HUMAN FAILURE EVENTS

Energy Technology Data Exchange (ETDEWEB)

Herberger, Sarah M.; Boring, Ronald L.

2016-10-01

Abstract Objectives: Human reliability analysis (HRA) methods typically analyze human failure events (HFEs) at the overall task level. For dynamic HRA, it is important to model human activities at the subtask level. There exists a disconnect between dynamic subtask level and static task level that presents issues when modeling dynamic scenarios. For example, the SPAR-H method is typically used to calculate the human error probability (HEP) at the task level. As demonstrated in this paper, quantification in SPAR-H does not translate to the subtask level. Methods: Two different discrete distributions were generated for each SPAR-H Performance Shaping Factor (PSF) to define the frequency of PSF levels. The first distribution was a uniform, or uninformed distribution that assumed the frequency of each PSF level was equally likely. The second non-continuous distribution took the frequency of PSF level as identified from an assessment of the HERA database. These two different approaches were created to identify the resulting distribution of the HEP. The resulting HEP that appears closer to the known distribution, a log-normal centered on 1E-3, is the more desirable. Each approach then has median, average and maximum HFE calculations applied. To calculate these three values, three events, A, B and C are generated from the PSF level frequencies comprised of subtasks. The median HFE selects the median PSF level from each PSF and calculates HEP. The average HFE takes the mean PSF level, and the maximum takes the maximum PSF level. The same data set of subtask HEPs yields starkly different HEPs when aggregated to the HFE level in SPAR-H. Results: Assuming that each PSF level in each HFE is equally likely creates an unrealistic distribution of the HEP that is centered at 1. Next the observed frequency of PSF levels was applied with the resulting HEP behaving log-normally with a majority of the values under 2.5% HEP. The median, average and maximum HFE calculations did yield

Human factors engineering applications to the cask design activities of the Civilian Radioactive Waste Management Program

International Nuclear Information System (INIS)

Lake, W.H.; Peck, M. III

1993-01-01

The use of human factors engineering (HFE) in the design and use of spent fuel casks being developed for the Department of Energy's Civilian Radioactive Waste Management Program is addressed. The safety functions of cask systems are presented as background for HFE considerations. Because spent fuel casks are passive safety devices they could be subject to latent system failures due to human error. It is concluded that HFE should focus on operations and verifications tests, but should begin, to the extent possible, at the beginning of cask design. Use of HFE during design could serve to eliminate or preclude opportunity for human error

Relaciones de la grasa visceral y de tronco con el sindrome metabólico

OpenAIRE

Fernández Vázquez, Rosalía Asunción

2016-01-01

La obesidad central es uno de los componentes que conforman el conjunto de factores del síndrome metabólico. La obesidad central se asocia a una gran incidencia de diabetes tipo 2, resistencia a la insulina, hipertensión arterial y particularmente a las enfermedades cardiovasculares. Las acciones metabólicas del tejido adiposo visceral son por sí solas un factor de riesgo independiente para una serie de alteraciones metabólicas. Objetivos: Los objetivos de la presente tesis han sido estudiar ...

Leucoencefalopatía posterior reversible secundaria a glomerulonefritis postestreptocócica: a propósito de un caso

OpenAIRE

BAZZINO, FERNANDO; PANDOLFO, SOLEDAD; PROTASIO, LAURA; PUJADAS, MóNICA; CERISOLA, ALFREDO; GONZáLEZ, GABRIEL; CAGGIANI, MARINA; RUBIO, IVONNE

2005-01-01

Resumen La leucoencefalopatía posterior reversible (LEPR) es una entidad clínico-radiológica que afecta habitualmente la sustancia blanca de los hemisferios cerebrales. Se asocia con frecuencia a hipertensión arterial aguda y al tratamiento inmunosupresor, entre otras causas. La presentación clínica es variada, con cefaleas, náuseas, vómitos, deterioro de conciencia y alteración en el comportamiento, convulsiones y trastornos visuales, síntomas que frecuentemente retroceden. La tomografía axi...

Asociación entre el déficit de vitamina D y bienestar emocional en pacientes con Diabetes Mellitus tipo 1

OpenAIRE

Waselle Vallina, Rebeca

2016-01-01

Introducción: La deficiencia de vitamina D se asocia con un mayor riesgo de padecer enfermedades autoinmunes, como sería el caso de los pacientes con diabetes mellitus tipo 1. Esta enfermedad tiene un impacto, sobre la calidad de vida y el bienestar emocional de los pacientes, relacionado con el control glucémico, las complicaciones y algunas variables socioeconómicas. Objetivos: El objetivo principal fue evaluar el grado de asociación entre la vitamina D y el bienestar emocional de los ...

Comorbilidades y calidad de vida en Osteoartritis

OpenAIRE

Solis Cartas, Urbano; Calvopiña Bejarano, Silvia Johana

2018-01-01

RESUMEN Introducción: la osteoartritis es considerada la enfermedad reumática más antigua y frecuente que existe. A pesar de ser considerada una patología benigna se asocia a un gran número de comorbilidades que pueden influir en el curso de la enfermedad. Objetivo: determinar la influencia de las comorbilidades en la percepción de la calidad de vida relacionada con la salud en pacientes con osteoartritis del cantón Riobamba. Método: estudio descriptivo, transversal y observacional ...

Hipoglicemiantes orales para el tratamiento de la diabetes mellitus gestacional: Revisión sistemática de la literatura

OpenAIRE

Pavlovic B,Milenko; Carvajal C,Jorge

2013-01-01

Antecedentes: La diabetes mellitus gestacional (DMG) se asocia a mayor riesgo materno y perinatal. El manejo habitual de ésta patología es la dieta, el ejercicio y la insulina. Los hipoglicemiantes orales (HGO) son una terapia emergente para el tratamiento de la DMG. Objetivos: Realizar una revisión sistemática de toda la evidencia tipo I disponible acerca del uso de HGO para tratamiento de DMG y realizar un metaanálisis de los resultados maternos y perinatales significativos. Resultados: Die...

Aditivos alimentarios: ¿qué son, cómo actúan, por qué son tan necesarios?

OpenAIRE

Blanco de Alvarado-Ortiz, Teresa

2014-01-01

Para John M. deMan, en su obra PrincipIes of Food Chemistry a los aditivos alimentarios con frecuencia se les asocia a algo químico, otorgándose erradamente a lo quimico características de artificial, no siempre bueno para la salud.Dicen bien erradamente, porque hombres, animales, plantas, microorganismos, alimentos, aire, cerros, minas y todo lo que nos rodea en la maravillosa naturaleza, es químico. Los aditivos alimentarios,todos químicos, naturales o artificiales son extraordinarias susta...

MORTALIDAD YCOSTES ASOCIADOS A LA DEMORA DEL TRATAMIENTO QUIRÚRGICO POR FRACTURA DE CADERA

OpenAIRE

Iñigo Etxebarria-Foronda; Javier Mar; Arantzazu Arrospide; Jaime Ruiz de Eguino

2013-01-01

Fundamentos: La intervención quirúrgica en las fracturas de cadera suele demorarse varios días. Nuestro trabajo tiene dos objetivos. Estudiar la estancia preoperatoria de los pacientes ingresados por fractura de cade- ra en los hospitales vascos durante el año 2010 y medir su posible asocia- ción con la mortalidad intrahospitalaria, y estimar el coste económico que supone la estancia preoperatoria. Métodos. Se realizó un estudio observacional analizando los siguien- tes datos del Conjunto Mín...

La lectura en el aula. Qué se hace, qué se debe hacer y qué se puede hacer

OpenAIRE

Pablo Lorente Muñoz

2011-01-01

Emilio Sánchez Miguel (Coord.). La lectura en el aula. Qué se hace, qué se debe hacer y qué se puede hacer. Graó, col. Crítica y Fundamentos, 27. Barcelona, 2010. 382 págs. ISBN: 978-84-7827-892-3

SE-VYZ

International Nuclear Information System (INIS)

Anon

2004-01-01

On this CD compact disc 6 video-films (A-1 NPP; Bituminization; Cementation; Pressing; The Interim spent fuel storage facility; Transport into the National radioactive waste repository Mochovce; Ignition; and Vitrification). In these films process of radioactive waste treatment in the Bohunice Radioactive Waste Processing Center (SE-VYZ) is presented. 2 presentations about radioactive wastes treatment in the SE-VYZ are included

Slow high-frequency effects in mechanics: problems, solutions, potentials

DEFF Research Database (Denmark)

Thomsen, Jon Juel

2005-01-01

– an apparent change in the stiffness associated with an equilibrium; Biasing – a tendency for a system to move towards a particular state which does not exist or is unstable without HFE; and Smoothening – a tendency for discontinuities to be apparently smeared out by HFE. The effects and a method for analyzing...... and compared: The Method of Direct Separation of Motions, the Method of Averaging, and the Method of Multiple Scales. The tutorial concludes by suggesting that more vibration experts, researchers and students should know about HFE effects, for the benefit not only of general vibration troubleshooting, but also......Strong high-frequency excitation (HFE) may change the ‘slow’ (i.e. effective or average) properties of mechanical systems, e.g. their stiffness, natural frequencies, equilibriums, equilibrium stability, and bifurcation paths. This tutorial describes three general HFE effects: Stiffening...

Slow high-frequency effects in mechanics: problems, solutions, potentials

DEFF Research Database (Denmark)

Thomsen, Jon Juel

– an apparent change in the stiffness associated with an equilibrium; Biasing – a tendency for a system to move towards a particular state which does not exist or is unstable without HFE; and Smoothening – a tendency for discontinuities to be apparently smeared out by HFE. The effects and a method for analyzing...... and compared: The Method of Direct Separation of Motions, the Method of Averaging, and the Method of Multiple Scales. The tutorial concludes by suggesting that more vibration experts, researchers and students should know about HFE effects, for the benefit not only of general vibration troubleshooting, but also......Strong high-frequency excitation (HFE) may change the ‘slow’ (i.e. effective or average) properties of mechanical systems, e.g. their stiffness, natural frequencies, equilibriums, equilibrium stability, and bifurcation paths. This tutorial describes three general HFE effects: Stiffening...

Speciation of Se and DOC in soil solution and their relation to Se bioavailability.

Science.gov (United States)

Weng, Liping; Vega, Flora Alonso; Supriatin, Supriatin; Bussink, Wim; Van Riemsdijk, Willem H

2011-01-01

A 0.01 M CaCl(2) extraction is often used to asses the bioavailability of plant nutrients in soils. However, almost no correlation was found between selenium (Se) in the soil extraction and Se content in grass. The recently developed anion Donnan membrane technique was used to analyze chemical speciation of Se in the 0.01 M CaCl(2) extractions of grassland soils and fractionation of DOC (dissolved organic carbon). The results show that most of Se (67-86%) in the extractions (15 samples) are colloidal-sized Se. Only 13-34% of extractable Se are selenate, selenite and small organic Se (<1 nm). Colloidal Se is, most likely, Se bound to or incorporated in colloidal-sized organic matter. The dominant form of small Se compounds (selenate, selenite/small organic compounds) depends on soil. A total of 47-85% of DOC is colloidal-sized and 15-53% are small organic molecules (<1 nm). In combination with soluble S (sulfur) and/or P (phosphor), concentration of small DOC can explain most of the variability of Se content in grass. The results indicate that mineralization of organic Se is the most important factor that controls Se availability in soils. Competition with sulfate and phosphate needs to be taken into account. Further research is needed to verify if concentration of small DOC is a good indicator of mineralization of soil organic matter.

One-pot synthesis of hollow NiSe-CoSe nanoparticles with improved performance for hybrid supercapacitors

Science.gov (United States)

Chen, Haichao; Fan, Meiqiang; Li, Chao; Tian, Guanglei; Lv, Chunju; Chen, Da; Shu, Kangying; Jiang, Jianjun

2016-10-01

Hollow NiSe-CoSe samples have been synthesized for the first time via a one-pot solvothermal approach. The strategy is robust enough to synthesize NiSe-CoSe nanoparticles with different NiSe to CoSe ratios but with a similar hollow structure. Co ions in the NiSe-CoSe nanoparticles play decisive role for formation of the hollow structure; otherwise, the nanoparticles become solid for the NiSe sample. When used as the positive electroactive materials for energy storage, the NiSe-CoSe samples show excellent electrochemical activity in alkaline electrolyte. Using the synergistic effect between NiSe and CoSe, the electrochemical performance of NiSe-CoSe can be tuned by varying the NiSe to CoSe ratios. The NiSe-CoSe sample with a NiSe to CoSe ratio of 4:2 shows the best electrochemical performance in terms of superior specific capacity, improved rate capability and excellent cycling stability. In addition, the electrochemical performance of NiSe-CoSe sample with a NiSe to CoSe ratio of 4:2 is also evaluated via assembling hybrid supercapacitors with RGO, and the hybrid supercapacitor delivers both high power and energy densities (41.8 Wh kg-1 at 750 W kg-1 and 20.3 Wh kg-1 at 30 kW kg-1).

La ciudad en sus niños. La calidad de vida en percepción infantil

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Héctor Mauricio Rojas-Betancur

2013-01-01

Full Text Available En esta investigación se analiza la calidad de vida desde la percepción de los niños en un contexto urbano centrado en aspectos subjetivos. El estudio se realizó con 166 niños de la ciudad de Bucaramanga, Colombia, aplicando un instrumento estructurado sobre percepción de calidad de vida en la ciudad. Se destaca la construcción de un concepto multifacético en la experiencia urbana inmediata de los niños y una preocupación infantil generalizada por los temas ambientales en la ciudad, la inseguridad personal y una sentida necesidad de más espacios escolares y recreativos, además, la queja infantil por la falta de cultura ciudadana en múltiples expresiones. Se concluye cómo el concepto de calidad de vida en la niñez se asocia poco al ser y más al tener o al carecer de algún aspecto valorado como importante.

Breve reseña histórica sobre tisiocirugía

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Bárbaro Agustín Armas Pérez

Full Text Available La tuberculosis o "peste blanca" fue un azote mundial, comparable hoy día con el síndrome de inmunodeficiencia adquirida, al que se asocia, pues "nunca enfermo alguno sufrió tanto ni fue tan despreciado". El 24 de marzo de 1882 Robert Koch mostró el bacilo que causaba la tisis o consunción, y desde entonces esa fecha se reconoce como el Día Mundial contra la Tuberculosis. Se presenta una revisión del tema ante el LIV Aniversario del Hospital "Amalia Simoni", inicialmente antituberculoso. El objetivo secundario es homenajear a todos sus trabajadores, en especial a los fundadores. Se describen los tipos de tratamiento quirúrgico utilizados a través del tiempo, desde la cavernotomía hasta las resecciones pulmonares. Muchas técnicas y principios modernos de la cirugía torácica se desarrollaron a partir de la tisiocirugía.

Risk factors for development of dementia in a unique six-year cohort study. I. An exploratory, pilot study of involvement of the E4 allele of apolipoprotein E, mutations of the hemochromatosis-HFE gene, type 2 diabetes, and stroke.

Science.gov (United States)

Percy, Maire; Somerville, Martin J; Hicks, Mark; Garcia, Angeles; Colelli, Teresa; Wright, Emily; Kitaygorodsky, Julia; Jiang, Amy; Ho, Valerie; Parpia, Alyssa; Wong, Michael K

2014-01-01

Risk factors for dementia development are not well-defined. We evaluated several factors alone and in combination in a unique cohort of Caucasian volunteers over an approximately 6-year observation window using a nested case/control design. Factors included: apolipoprotein E (ApoE) gene variants (the E4 allele is the strongest confirmed genetic predisposing factor for Alzheimer's disease), the hemochromatosis-HFE gene mutations (H63D and C282Y), diabetes, and stroke. At study entry, subjects were ≥65 years of age (M ± SD = 73.0 ± 4.9), had an MMSE score ≥24, and no evidence of cerebrovascular disease or current depression. Genotyping was completed on 163 available DNA samples from three different groups at the study end: those who still had normal cognitive function; those who had developed dementia; and those with Mild Cognitive Impairment (MCI). Analyses were interpreted at the 95% confidence level without Bonferroni corrections. In the subgroup with dementia, all cases of diabetes were type 2 and present at study entry, whereas all strokes occurred during the study. The results highlight apparently synergistic interactions between genetic and medical risk factors for dementia development, gender differences in risk factors, and involvement of HFE mutations. Having E4 (i.e., either of E3/4 or E4/4), C282Y, H63D, diabetes, or stroke alone did not attain significance. Significant predisposing factors with post-hoc power ≥80% were: E4 homozygosity (E4/4)males+females, odds ratio (OR) = 56.0); E4+diabetes (males+females, OR = 13.7; E4+H63D+diabetes (females, OR = 52.0); E4+stroke (males, OR = 46.5). The importance of preventing diabetes and stroke to ward off dementia and the possible role of iron dysmetabolism in dementia are discussed.

Excitons, biexcitons, and phonons in ultrathin CdSe/ZnSe quantum structures

DEFF Research Database (Denmark)

Gindele, F.; Woggon, Ulrike; Langbein, Wolfgang Werner

1999-01-01

The optical properties of CdSe nanostructures grown by migration-enhanced epitaxy of CdSe on ZnSe are studied by time-, energy-, and temperature-dependent photoluminescence and excitation spectroscopy, as well as by polarization-dependent four-wave mixing and two-photon absorption experiments...

Importancia del apoyo familiar en el control de la glucemia

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RODRÍGUEZ-MORÁN MARTHA

1997-01-01

Full Text Available Objetivo. Determinar la importancia del apoyo familiar en el control de la glucemia en diabéticos no insulino dependientes. Material y métodos. Se diseñó un estudio de casos y controles, considerando como casos a los pacientes con glucemia o = 140 mg/dl. El apoyo familiar se determinó con el cuestionario Environmental Barriers to Adherence Scales, que estima el apoyo otorgado para que el paciente siga las indicaciones terapéuticas. Se incluyeron 32 casos y 50 controles. Resultados. El apoyo familiar que recibe el paciente se asocia significativamente a la presencia de glucemia <140 mg/dl (razón de momios = 3.9; IC95% 1.4-11.1. Las demás variables no mostraron asociación significativa. Conclusiones. El apoyo familiar que reciben los enfermos influye en el control de la glucemia.

Asociación entre el precio de los alimentos y la glucemia en adultos estadounidenses con diabetes de tipo 2

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Tobenna D. Anekwé

2015-06-01

Full Text Available OBJETIVOS: Calculamos la asociación entre el precio de diversas categorías de alimentos saludables y menos saludables y la glucemia en adultos estadounidenses con diabetes de tipo 2. MÉTODOS: Vinculamos la información de salud contenida en la Encuesta Nacional de Salud y Nutrición 1999-2006 y el precio de los alimentos a partir de la base trimestral de datos de precios de los alimentos. Aplicamos una regresión de los valores de glucemia con respecto al precio de los alimentos en el trimestre anterior, con control de la región del mercado y otras covariables. Examinamos asimismo si la asociación entre el precio de los alimentos y la glucemia variaba entre distintos grupos de ingresos. RESULTADOS: Tanto el precio de las frutas y verduras como el precio de los productos lácteos magros se asocian a la glucemia en las personas con diabetes de tipo 2. En concreto, un precio mayor de las frutas y verduras y de los productos lácteos se asocia a valores más altos de glu-cohemoglobina y de glucemia en ayunas tres meses después. La asociación entre el precio de los alimentos y la glucemia es mayor en las personas de ingresos bajos que en las de ingresos elevados, en la dirección esperada. CONCLUSIONES: Un precio mayor de los alimentos saludables se asocia a cifras más elevadas de glucemia en las personas con diabetes de tipo 2. Esta asociación fue especialmente pronunciada en las personas con diabetes de tipo 2 con ingresos bajos.

Improved photoluminescence quantum yield and stability of CdSe-TOP, CdSe-ODA-TOPO, CdSe/CdS and CdSe/EP nanocomposites

Science.gov (United States)

Wei, Shutian; Zhu, Zhilin; Wang, Zhixiao; Wei, Gugangfen; Wang, Pingjian; Li, Hai; Hua, Zhen; Lin, Zhonghai

2016-07-01

Size-controllable monodisperse CdSe nanocrystals with different organic capping were prepared based on the hot-injection method. The effective separation of nucleation and growth was achieved by rapidly mixing two highly reactive precursors. As a contrast, we prepared CdSe/CdS nanocrystals (NCs) successfully based on the selective ion layer adsorption and reaction (SILAR) technique. This inorganic capping obtained higher photoluminescence quantum yield (PLQY) of 59.3% compared with organic capping of 40.8%. Furthermore, the CdSe-epoxy resin (EP) composites were prepared by adopting a flexible ex situ method, and showed excellent stability in the ambient environment for one year. So the composites with both high PLQY of nanocrystals and excellent stability are very promising to device application.

Effects of highly conserved major histocompatibility complex (MHC extended haplotypes on iron and low CD8+ T lymphocyte phenotypes in HFE C282Y homozygous hemochromatosis patients from three geographically distant areas.

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Mónica Costa

Full Text Available Hereditary Hemochromatosis (HH is a recessively inherited disorder of iron overload occurring commonly in subjects homozygous for the C282Y mutation in HFE gene localized on chromosome 6p21.3 in linkage disequilibrium with the human leukocyte antigen (HLA-A locus. Although its genetic homogeneity, the phenotypic expression is variable suggesting the presence of modifying factors. One such genetic factor, a SNP microhaplotype named A-A-T, was recently found to be associated with a more severe phenotype and also with low CD8(+T-lymphocyte numbers. The present study aimed to test whether the predictive value of the A-A-T microhaplotype remained in other population settings. In this study of 304 HH patients from 3 geographically distant populations (Porto, Portugal 65; Alabama, USA 57; Nord-Trøndelag, Norway 182, the extended haplotypes involving A-A-T were studied in 608 chromosomes and the CD8(+ T-lymphocyte numbers were determined in all subjects. Patients from Porto had a more severe phenotype than those from other settings. Patients with A-A-T seemed on average to have greater iron stores (p = 0.021, but significant differences were not confirmed in the 3 separate populations. Low CD8(+ T-lymphocytes were associated with HLA-A*03-A-A-T in Porto and Alabama patients but not in the greater series from Nord-Trøndelag. Although A-A-T may signal a more severe iron phenotype, this study was unable to prove such an association in all population settings, precluding its use as a universal predictive marker of iron overload in HH. Interestingly, the association between A-A-T and CD8(+ T-lymphocytes, which was confirmed in Porto and Alabama patients, was not observed in Nord-Trøndelag patients, showing that common HLA haplotypes like A*01-B*08 or A*03-B*07 segregating with HFE/C282Y in the three populations may carry different messages. These findings further strengthen the relevance of HH as a good disease model to search for novel candidate loci

Dezvoltarea asociațiilor în România

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Cristian ANGHEL

2000-10-01

Full Text Available The Development of Romanian Associations  The associations/federations of local authorities are: 1. The National Union of County Councils from Romania; 2. The Federation of Municipalities from Romania; 3. The Federations of Towns from Romania; 4. The Association of Villages from Romania. In Romania, the associations/federations of local authorities are real centres for implementing a democratic management style in local government, bringing their contribution in administrative, social and economic reform. The role of this associative structures is: _ To support the local authorities activities; _ To represent the local authorities interests by influencing the legislative process and by correct implementing of normative acts; _ To make experience exchanges, in the idea of improving the quality of public services. The activity of these associations/federations is based on co-operation, consensus, to eliminate the non-implication principle. Activity area: 1. Decentralization; 2. Local Government Management; 3. Local Economic Development; 4. Local Public Finance; 5. Local Public Services Modernization; 6. Human Resources Policy; 7. Regional and Local Co-operation; 8. Democratization and Modernization of Social Life. These associations/federations proved their importance in all these years and we have to mention the disponibility to create and preserv an optimum national and international networking.

Preventing healthcare-associated infections through human factors engineering.

Science.gov (United States)

Jacob, Jesse T; Herwaldt, Loreen A; Durso, Francis T

2018-05-24

Human factors engineering (HFE) approaches are increasingly being used in healthcare, but have been applied in relatively limited ways to infection prevention and control (IPC). Previous studies have focused on using selected HFE tools, but newer literature supports a system-based HFE approach to IPC. Cross-contamination and the existence of workarounds suggest that healthcare workers need better support to reduce and simplify steps in delivering care. Simplifying workflow can lead to better understanding of why a process fails and allow for improvements to reduce errors and increase efficiency. Hand hygiene can be improved using visual cues and nudges based on room layout. Using personal protective equipment appropriately appears simple, but exists in a complex interaction with workload, behavior, emotion, and environmental variables including product placement. HFE can help prevent the pathogen transmission through improving environmental cleaning and appropriate use of medical devices. Emerging evidence suggests that HFE can be applied in IPC to reduce healthcare-associated infections. HFE and IPC collaboration can help improve many of the basic best practices including use of hand hygiene and personal protective equipment by healthcare workers during patient care.

Thermoelectric transport of Se-rich Ag2Se in normal phases and phase transitions

International Nuclear Information System (INIS)

Mi, Wenlong; Lv, Yanhong; Qiu, Pengfei; Shi, Xun; Chen, Lidong; Zhang, Tiansong

2014-01-01

Small amount of Se atoms are used to tune the carrier concentrations (n H ) and electrical transport in Ag 2 Se. Significant enhancements in power factor and thermoelectric figure of merit (zT) are observed in the compositions of Ag 2 Se 1.06 and Ag 2 Se 1.08 . The excessive Se atoms do not change the intrinsically electron-conducting character in Ag 2 Se. The detailed analysis reveals the experiment optimum carrier concentration in Ag 2 Se is around 5 × 10 18  cm −3 . We also investigate the temperature of maximum zT and the thermoelectric transport during the first order phase transitions using the recently developed measurement system

Contenha-se, se for capaz

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Mirna Feitoza Pereira

2008-11-01

Full Text Available Em O Instinto da Linguagem, Steven Pinker discorre sobre sua célebre tese: a linguagem não é a mais prodigiosa invenção cultural humana. Ela é uma peça da constituição biológica do cérebro. A linguagem é uma habilidade complexa e especializada, que se desenvolve espontaneamente na criança, sem qualquer esforço consciente ou instrução formal, que se manifesta sem que se perceba sua lógica subjacente, que é qualitativamente a mesma em todo indiví­duo, e que difere de capacidades mais gerais de processamento de informações ou de comportamento inteligente. Para Pinker, a concepção de linguagem como um tipo de instinto transmite a idéia de que as pessoas sabem falar mais ou menos da mesma maneira que as aranhas sabem tecer suas teias. Ele apóia suas idéias em Darwin e Chomsky. Palavras-chave linguagem, gramática universal, evolução Abstract In Language Instinct, Steven Pinker argues about his famous thesis: language is not the most prodigious human cultural invention. It is a distinct piece of the biological constitution of the brain. Language is a complex, specialized skill, which develops spontaneously in the child, without conscious effort or formal instruction. It reveals itself without awareness of its underlying logic, which is qualitatively the same in every individual, and which is distinct from more general abilities of information processing of intelligent behavior. According to Pinker, the conception of language as a kind of instinct conveys the idea that people know how to talk in more or less the same way as spiders know how to spin webs. His thesis is founded in Darwin and Chomsky-s theories. Keywords language, universal grammar, evolution

Acute Free-Iron Exposure Does Not Explain the Impaired Haemorheology Associated with Haemochromatosis.

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Antony P McNamee

Full Text Available Given the severity of the current imbalance between blood donor supply and recipient demand, discarded blood drawn from the routine venesections of haemochromatosis (HFE-HH patients may serve as a valuable alternative source for blood banks and transfusion. We investigated whether functional or biochemical differences existed between HFE-HH and control blood samples, with particular focus upon the haemorheological properties, to investigate the viability of venesected blood being subsequently harvested for blood products.Blood samples were collected from HFE-HH patients undergoing venesection treatment (n = 19 and healthy volunteers (n = 8. Moreover, a second experiment investigated the effects of a dose-response of iron (0, 40, 80, 320 mM FeCl3 on haemorheology in healthy blood samples (n = 7. Dependent variables included basic haematology, iron status, haematocrit, red blood cell (RBC aggregation (native and standardised haematocrit and "aggregability" (RBC tendency to aggregate in a standard aggregating medium; 0.4 L/L haematocrit in a Dx70, and RBC deformability.Indices of RBC deformability were significantly decreased for HFE-HH when compared with healthy controls: RBC deformability was significantly decreased at 1-7 Pa (p < 0.05, and the shear stress required for half maximal deformability was significantly increased (p < 0.05 for HFE-HH. RBC aggregation in plasma was significantly increased (p < 0.001 for HFE-HH, although when RBC were suspended in plasma-free Dx70 no differences were detected. No differences in RBC deformability or RBC aggregation/aggregability were detected when healthy RBC were incubated with varying dose of FeCl3.HFE-HH impairs the haemorheological properties of blood; however, RBC aggregability was similar between HFE-HH and controls when cells were suspended in a plasma-free medium, indicating that plasma factor(s may explain the altered haemorheology in HFE-HH patients. Acute exposure to elevated iron levels does

EPR of SeO2- and SeO3- radicals in alkaline borate glasses with 77Se isotope

International Nuclear Information System (INIS)

Galimov, D.G.; Tarzimanov, K.D.

1977-01-01

Alkaline borate glasses with 77 Se were investigated in order to establish the nature of selenium compounds and radicals in glasses. The relationship between alkali ions and the oxygen radical of selenium was determined by decoding the hyperfine structure of the alkaline borate glass EPR spectra obtained before and after γ-irradiation. The irradiated and non-irradiated glasses were characterized by hyperfine splitting of the EPR lines from the α- and β centres. Moreover, the irradiated samples were noted to have a line doublet (signal phi). With intenser reduction conditions of glass fusion, the intensities of α, β, and phi signals were noted to decline. This confirmes the suggestion that these centres were caused by oxygen compouds. The authors concluded that α and β signals were due to the paramagnetic centres of SeO 2 - and [SeO 2 - ]R + , and phi signal to the SeO 3 - radicals

Mutaciones del gen de la Hemocromatosis en donantes de sangre voluntarios y en pacientes con Porfiria cutánea tarda en Chile Mutations of hemochromatosis gene in volunteer blood donors and Chilean porphyria cutanea tarda patients

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Carlos Wolff F

2006-10-01

Full Text Available La acumulación de hierro hepático asociada a mutaciones en el gen HFE de la hemocromatosis hereditaria (HH en los pacientes con porfiria cutánea tarda (PCT podría tener un papel en la etiología y en la expresión clínica de esta enfermedad. Se estudió la frecuencia de las mutaciones H63D y C282Y en un grupo de pacientes con PCT y se la comparó con la observada en un grupo de donantes voluntarios de sangre. Los pacientes con PCT fueron catalogados como portadores de la forma hereditaria o adquirida de la enfermedad, según presentaran o no mutaciones en el gen uroporfirinógeno decarboxilasa (UROD. El 50% de los pacientes con PCT eran portadores de la forma genética de la enfermedad, porcentaje significativamente mayor que lo informado en otras series. El 23% de los donantes voluntarios de sangre eran portadores de la mutación H63D y 2.4% lo era de la mutación C282Y. Frecuencias similares a lo encontrado por otros autores en población chilena de etnia blanca, en población argentina y española, pero significativamente más alta que lo encontrado en estudios en población aborigen araucana. Esto tiene, probablemente, relación con el predominio de ascendencia española en la población blanca chilena. La frecuencia de mutación en el gen HFE en pacientes con PCT no fue significativamente diferente que la observada en donantes voluntarios de sangre. Tampoco hubo diferencias significativas en la frecuencia de estas mutaciones entre los casos con PCT adquirida respecto de aquellos en que ésta era de origen genético. Los resultados obtenidos no permiten afirmar que exista asociación entre la PCT y la condición de portador de mutaciones del gen HFE de la hemocromatosis hereditaria.In patients with porphyria cutanea tarda (PCT, hepatic iron accumulation associated to hereditary hemochromatosis (HH could play a role in the etiology and in the clinical expression of the disease. The H63D and C282Y mutations of the HFE gene frequency were

Tratamiento de la hipertensión arterial en el paciente con síndrome metabólico

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Patricio López-Jaramillo, MD., PhD.

2010-01-01

Full Text Available El síndrome metabólico afecta alrededor de 25% a 45% de la población colombiana de acuerdo con los criterios diagnósticos propuestos por la Federación Internacional de Diabetes, los cuales, en nuestra población, aparecen como los más útiles. Bien se sabe que el síndrome metabólico se asocia con un incremento tres a seis veces en el riesgo de desarrollar diabetes y nuevos casos de hipertensión. En Colombia, un estudio de cohorte realizado en pacientes que sufrieron infarto agudo del miocardio, demostró que la resistencia a la insulina fue el principal factor que predijo muerte cardiovascular o presencia de nuevos eventos cardio-cerebro-vasculares. Además, la presencia de síndrome metabólico se asocia con más frecuencia a daño subclínico de órgano blanco. El principal tratamiento en sujetos con síndrome metabólico es la reducción del peso corporal a través de la implementación de una dieta baja en calorías y aumento del ejercicio físico. Así, los pacientes con este síndrome necesitan la administración adicional de medicamentos antihipertensivos, antidiabéticos orales o fármacos hipolipemiantes cuando existe franca hipertensión, diabetes o dislipidemia. En vista de que el riesgo cardiovascular es alto en pacientes hipertensos con síndrome metabólico, es necesario hacer un riguroso control de la presión arterial, manteniendo los niveles siempre por debajo de 130/85 mm Hg. A no ser que existan indicaciones específicas, en los pacientes con síndrome metabólico se debe evitar el uso de beta-bloqueadores, ya que son bien conocidos sus efectos adversos en el aumento de peso, en la incidencia de nuevos casos de diabetes, en la resistencia a la insulina y en el perfil lipídico. Los diuréticos tiazídicos presentan efectos diabetogénicos y otras acciones dismetabólicas, especialmente a dosis altas, por lo que no deben utilizarse en pacientes con síndrome metabólico. Por lo tanto, los fármacos recomendados como

Se-Se isoelectronic centers in high purity CdTe

Energy Technology Data Exchange (ETDEWEB)

Najjar, Rita; Andre, Regis; Mariette, Henri [CEA-CNRS, Nanophysique et Semiconducteurs, Institut Neel, 25 rue des martyrs, 38042 Grenoble (France); Golnik, Andrzej; Kossacki, Piotr; Gaj, Jan A. [Institute of Experimental Physics, University of Warsaw, Hoza 69, 00-681 Warsaw (Poland)

2010-06-15

We evidence zero-dimensional exciton states trapped on isoelectronic Se centers in CdTe quantum wells, {delta}-doped with Se. Thanks to special precautions taken to have very high purity CdTe heterostructures, it is possible to observe, in photoluminescence spectra, sharp discrete lines arising from individual centers related to the Se doping. These emission lines appear at about 40 meV below the CdTe band gap energy. The most prominent lines are attributed to the recombination of excitons bound to nearest-neighbor selenium pairs in a tetrahedral CdTe environment. This assignment is confirmed by a common linear polarization direction of the emitted light, parallel to <110>. These excitons localized on individual isoelectronic traps are good candidates as single photon emitters (copyright 2010 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

La preeclampsia un problema de salud pública mundial

OpenAIRE

Vargas H,Víctor Manuel; Acosta A,Gustavo; Moreno E,Mario Adán

2012-01-01

La preeclampsia es un problema de salud pública y una de las principales causas de muerte materna. La prevalencia oscila entre 1,8-16,7%. La causa sigue desconocida y se asocia a problemas de salud importantes, existiendo muchos retos para la predicción, prevención y tratamiento. Las medidas profilácticas como dosis baja de aspirina y suplementos de calcio, requieren mayor evidencia para uso rutinario. El control prenatal, diagnóstico oportuno, manejo adecuado, y parto son las medidas más efi...

Cirugía bariátrica previo a embarazo y su impacto en el resultado perinatal

OpenAIRE

Fernando Andres Ferrer Márquez; Manuel Mundaca; Alejandra Ledezma Ledezma S.; Jorge A. Carvajal

2016-01-01

La obesidad en mujeres embarazadas se asocia a mal resultado materno y perinatal. El tratamiento de la obesidad, especialmente obesidad mórbida es complejo, muchas veces requiere del apoyo de técnicas quirúrgicas. La cirugía bariátrica es una solución eficiente para la obesidad al lograr pérdida de peso sostenida en el tiempo, lo que podría ayudar a disminuir las complicaciones asociadas a la obesidad durante el embarazo. En este trabajo presentamos realizar una revisión narrativa de la liter...

A propósito de un caso de malnutrición muy extrema en una paciente que presenta Anorexia Nerviosa Restrictiva de larga evolución y no recibía tratamiento

OpenAIRE

Pelegrina Cortés, Beatriz; Guillén Sacoto, María Augusta; Palma Milla, Samara; Lisbona Catalán, Arturo; Martín Fuentes, María; Gómez-Candela, Carmen

2014-01-01

La anorexia nerviosa es un trastorno de la conducta alimentaria que con frecuencia ocasiona malnutrición y asocia riesgo de mortalidad. Requiere la colaboración de un equipo multidisciplinar con amplia experiencia clínica para obtener óptimos resultados, una exitosa educación nutricional y evitar el síndrome de realimentación. El caso que se presenta constituye la malnutrición más severa secundaria a anorexia nerviosa que hemos tratado en nuestra unidad: una paciente de 33 años con IMC de 8.8...

Endocarditis infecciosa en pacientes diagnosticados de cirrosis hepática. ¿Está indicado el tratamiento quirúrgico?

Directory of Open Access Journals (Sweden)

Javier Miguelena

2016-05-01

Conclusiones: La cirrosis hepática empeora claramente el pronóstico de la EI, aumentando la mortalidad global del 19,2% al 37%. Además se asocia a una tasa de complicaciones mayores muy elevada. Aunque los pacientes en estadio A intervenidos quirúrgicamente presentaron una mortalidad inferior a quienes siguieron tratamiento médico exclusivamente, la elevada mortalidad en estadios más avanzados obliga a establecer la indicación quirúrgica de manera individualizada y procurar un cuidadoso manejo perioperatorio en estos pacientes.

Colgajo dermoglandular de apoyo en mastopexia con implantes: técnica de la hamaca

OpenAIRE

A. Alí; C. Zuleta-Bechara; V. Vassaro

2013-01-01

La ptosis mamaria es consulta frecuente en la práctica del cirujano plástico, y las opciones quirúrgicas para su corrección son múltiples. A pesar de los avances en el tratamiento de esta alteración, los resultados impredecibles y las posibles complicaciones siguen siendo frecuentes, sobre todo cuando se asocia la colocación de implantes mamarios. La dehiscencia de la herida, la exposición del implante y la modificación de la forma de la mama, en especial del polo inferior, pueden estar prese...

Hiperalgesia Inducida por Opioides

OpenAIRE

Jiménez Salazar, Andrés

2013-01-01

Los opioides producen analgesia a través de un efecto inhibitorio sobre el sistema nociceptivo principalmente. Hasta la fecha, los opioides siguen siendo los analgésicos más potentes para el manejo de dolor moderado a severo. La Asociación Internacional del Estudio del Dolor (IASP, en inglés) define hiperalgesia como "un aumento de la respuesta a un estímulo que normalmente es doloroso". En contraste, está bien establecido que la terapia crónica con opioides se asocia con el desarrollo de ...

El turismo oscuro: análisis de sitios web como herramienta de marketing

OpenAIRE

Barón Mosquera, José Luis

2017-01-01

El turismo es un sector cuya evolución ha provocado cambios en el modo en que los viajeros disfrutan su tiempo libre, dando lugar a nuevas formas de turismo. Una de estas nuevas ramas del turismo que está adquiriendo gran importancia es el “Dark tourism”, o turismo oscuro en español, en el que los turistas se sienten atraídos por lugares relacionados con la muerte, desmontando la idea clási ca que asocia la atracción turística a lo bello y a lo placentero(...

Un camino hacia ciudades seguras

OpenAIRE

Brust, Mariela E.; González, María Eugenia; Almandoz, María Paola; Colomar, Marcela; Saralegui, Paula

2015-01-01

Convocados a indagar sobre las ciudades vulnerables , donde la catástrofe no se asocia al destino sino a la imprevisión, y entendida ésta como la falta de previsión o reflexión; el presente trabajo pretende poner de manifiesto el estado actual de la prevención de accidentes y enfermedades laborales en las obras de arquitectura, a partir de conclusiones surgidas del análisis de los casos de estudio abordados en el proceso de investigación dirigido al estudio específico de las organizaciones la...

Implicaciones anestésicas de la obesidad en pacientes sometidas a una cesárea

OpenAIRE

Serrano, Mari Luz

2009-01-01

La obesidad en la embarazada debe ser considerada una situación de alto riesgo porque se asocia a complicaciones a corto y largo plazo. La obesidad supone un factor de riesgo anestésico. En el informe presentado en 2007 por "The Confidential Enquiry into Maternal and Child Health" (CEMACH) había seis muertes que estaban directamente relacionadas con la anestesia de las que cuatro eran pacientes obesas y dos obesas mórbidas. Además de la patología previa coexistente con la obesidad como ...

El síndrome de Kallmann. Correlación fenotipo-genotípica.

OpenAIRE

García Piñero, Alfonso José

2015-01-01

El Síndrome de Kallmann (SK) es una enfermedad genética del desarrollo, que asocia un hipogonadismo hipogonadotrópico (HH) congénito con pérdida total (anosmia) o parcial (hiposmia) del olfato. La alteración olfativa es secundaria a la aplasia o hipoplasia de las estructuras olfatorias (bulbos, tractos y surcos cerebrales olfatorios). El HH se debe a la deficiencia en la hormona liberadora de gonadotropinas hipotalámica (GnRH) como resultado del fallo en la migración de las neuronas productor...

Gluconacetobacter diazotrophicus: UN MICROORGANISMO PROMISORIO EN LA ELABORACIÓN DE BIOPREPARADOS

OpenAIRE

Yoania Ríos; B. Dibut

2007-01-01

Gluconacetobacter diazotrophicus, bacteria descubierta recientemente, se asocia a especies vegetales con altos contenidos de azúcares. Ello permite el incremento del nitrógeno disponible para la planta a partir del proceso de fijación biológica. El microorganismo libera al medio de hasta el 50 % de este elemento químico transformado. Además, posibilita el incremento de los rendimientos por la producción de sustancias fisiológicamente activas. A pesar de las diversas teorías en cuanto a la dis...

Mejoría mucosa endoscópica en pacientes con enfermedad inflamatoria intestinal

OpenAIRE

Veitia, Guillermo; Pernalete, Beatriz; La Cruz, María Alejandra; Rodríguez, María Josefina; Cachima, Lisbeth; Soto, José; Esquerre, Ivanova; Manuitt, Juan; Pérez, Guillermo

2014-01-01

La curación mucosa endoscópica en enfermedad inflamatoria intestinal se asocia con remisión clínica sostenida, reducción de hospitalizaciones y cirugía, pero lograrlo es difícil, según la literatura. Por ello evaluamos la mejoría mucosa endoscópica en nuestros pacientes. Objetivo: Evaluar la mejoría mucosa endoscópica en pacientes con enfermedad inflamatoria intestinal. Métodos: estudio multicéntrico, descriptivo, transversal. Incluyó 24 pacientes entre 17 y 73 años. Para evaluar respuesta a ...

Linfoma T Intestinal Monomórfico CD56+. Primer Caso Informado en Colombia y Revisión de la Literatura

Directory of Open Access Journals (Sweden)

Orlando Ricaurte G

2015-01-01

Full Text Available Mujer de 80 años con hallazgo incidental de masa abdominal en mesogastrio, a quien le realizan resección de intestino delgado por sospecha de absceso con síndrome adherencial. El estudio patológico de la pieza quirúrgica demostró compromiso por  linfoma no Hodgkin T monomórfico CD56+. Los linfomas T del tubo digestivo son inusuales, correspondiendo a 5% de las neoplasias linfoides de esta localización. El linfoma intestinal T monomórfico CD56+, corresponde a 10 - 20% de los linfomas T intestinales, se presenta en regiones donde la enfermedad celiaca es infrecuente y no se asocia a enteropatía. Su curso es agresivo y habitualmente se manifiesta como una emergencia quirúrgica por obstrucción o perforación intestinal.

Noradrenaline or terlipressin for hepatorenal syndrome?

Directory of Open Access Journals (Sweden)

Pilar Celis

2015-08-01

Full Text Available El síndrome hepatorrenal es una condición asociada a altísima mortalidad, que puede ser recuperada en ciertos casos con el uso de vasoconstrictores. Generalmente se considera que terlipresina es el tratamiento estándar, pero noradrenalina se ha planteado como una alternativa. Utilizando la base de datos Epistemonikos, la cual es mantenida mediante búsquedas en 30 bases de datos, identificamos seis revisiones sistemáticas que en conjunto incluyen cuatro estudios aleatorizados. Realizamos un metanálisis y tablas de resumen de los resultados utilizando el método GRADE. Concluimos que noradrenalina y terlipresina son probablemente igual de efectivas en lograr mejoría del síndrome hepatorrenal y disminuir la mortalidad, pero que noradrenalina se asocia a menos efectos adversos, y tiene un menor costo.

Sample Set (SE): SE30 [Metabolonote[Archive

Lifescience Database Archive (English)

Full Text Available SE30 Comparison of seed metabolites among soybean varieties Investigation of Glycine max. green seed metabol...ites. 3 varieties (Kamogawashichiri, Koitozairai, Tanbakuro) data are examined. Tak

Sample Set (SE): SE13 [Metabolonote[Archive

Lifescience Database Archive (English)

Full Text Available SE13 Comparison of leaf metabolites among spinach varieties Investigation of Spinacia oleracea leaf metaboli...tes. 4 cultivers (Nihon, Kanaji, Kurohaminstarland and Wasesaradaakari) and 3 repli

El aporte de la teoría fundamentada al estudio de la culpa en estafadores clasificados como altos y bajos en psicopatía

Directory of Open Access Journals (Sweden)

Benjamín Reyes Fernández

2011-01-01

Full Text Available Se plantea como problema de investigación: ¿cómo se relacionan cogniciones como la atribución causal y el sentido de los demás con la experiencia de culpa? Además, se reflexiona sobre qué es la Teoría Fundamentada y cómo contribuye a abordar el problema de investigación. Se entrevistaron 10 sujetos privados de libertad en Costa Rica por delito de estafa.. Se aplica la Lista de Chequeo de la Psicopatía a 34 privados de libertad. A aquellos con los puntajes más altos y más bajos se les realiza una entrevista. Las respuestas son analizadas según la versión straussiana de la Teoría Fundamentada. Se encuentran categorías novedosas que aparecieron a partir de los datos. Cuando se compara la presencia de éstas según los puntajes de psicopatía, se encuentra que la culpa se asocia con un locus más interno y controlable, y con un sentido de los demás que enfatiza los aspectos morales de las personas y sus situaciones.

Influence of CdSe layer air-baking on physical properties of CdSe-As2Se3 heterostructures

International Nuclear Information System (INIS)

Schauer, F.; Heza, S.; Kosek, F.; Cimpl, Z.

1980-01-01

An investigation is made of the influence of the air-baking time on the physical properties of a CdSe layer, which is a part of the heterogeneous structure CdSe-As 2 Se 3 used as a camera tube target. The I-U characteristics, C-U characteristics, the dependence of both the real and imaginary part admittance on frequency, and the photoconductance characteristics are measured. All measurements are carried out on heterostructures prepared with variable air-baking time of the CdSe layer: t =0, 5, 15, 40, and 120 min. The results of measurements contribute to the finding of the optimal production procedure with a minimum baking time of tsub(min) = 15 min. The heterostructures exhibit satisfactory properties. The dark current Isub(d)(U =1 V, T = 300 K) = 10 -10 Acm -2 with a rectification factor g(U = 10 V) = 10 6 and a capacitance C (2 kHz) = 2900 pFcm -2 . (author)

ZnSe MSM photodetectors prepared on GaAs and ZnSe substrates

International Nuclear Information System (INIS)

Lin, T.K.; Chang, S.J.; Su, Y.K.; Chiou, Y.Z.; Wang, C.K.; Chang, S.P.; Chang, C.M.; Tang, J.J.; Huang, B.R.

2005-01-01

Homoepitaxial and heteroepitaxial ZnSe metal-semiconductor-metal (MSM) photodetectors were both fabricated and characterized. It was found that homoepitaxial ZnSe MSM photodetector could provide us smaller dark current and large photocurrent. With an incident wavelength of 448 nm, it was found that the maximum responsivities for the homoepitaxial and heteroepitaxial ZnSe photodetectors were 0.128 and 0.045 A/W, which corresponds to a quantum efficiency of 36 and 12%, respectively. Furthermore, it was found that we achieved the minimum noise equivalent power (NEP) of 7.6 x 10 -13 W and the maximum normalized detectivity (D *) of 9.3 x 10 11 cm Hz 0.5 W -1 from our homoepitaxial ZnSe photodetector. In contrast, NEP and D * of the heteroepitaxial ZnSe photodetector were 2.9 x 10 -12 W and 2.44 x 10 11 cm Hz 0.5 W -1 , respectively

SE PREVENINDO?

Directory of Open Access Journals (Sweden)

Ana Débora Assis Moura

2010-01-01

Full Text Available Este estudio tuvo como objetivo verificar el comportamiento de las prostitutas en relación a la prevención de enfermedades de transmisión sexual y del Síndrome de Inmunodeficiencia Adquirida-SIDA, así como investigar cómo se previenen de esas enfermedades. Se trata de una investigación exploratoria, con enfoque cualitativo, llevada a cabo en la Asociación de las Prostitutas en Ceará, Brazil, en septiembre de 2008, a través de una encuesta con 25 prostitutas. El análisis de los datos se hizo según el análisis de contenido, después de ser agrupados en cuatro categorías: conocimiento sobre las enfermedades de transmisión sexual/SIDA; convivencia con la(s enfermedad(es; prevención de la enfermedad de transmisión sexual/SIDA; y el uso de drogas. Se concluyó que las prostitutas no usan preservativos en todas las relaciones sexuales, por lo tanto, las enfermedades de transmisión sexual representan una realidad; la desinformación sobre la(s enfermedad(es es notable; el consumo de drogas lícitas e ilícitas es frecuente entre ellas, factor que las expone a situaciones más vulnerables con relación al VIH/SIDA.

Building Secure Public Key Encryption Scheme from Hidden Field Equations

Directory of Open Access Journals (Sweden)

Yuan Ping

2017-01-01

Full Text Available Multivariate public key cryptography is a set of cryptographic schemes built from the NP-hardness of solving quadratic equations over finite fields, amongst which the hidden field equations (HFE family of schemes remain the most famous. However, the original HFE scheme was insecure, and the follow-up modifications were shown to be still vulnerable to attacks. In this paper, we propose a new variant of the HFE scheme by considering the special equation x2=x defined over the finite field F3 when x=0,1. We observe that the equation can be used to further destroy the special structure of the underlying central map of the HFE scheme. It is shown that the proposed public key encryption scheme is secure against known attacks including the MinRank attack, the algebraic attacks, and the linearization equations attacks. The proposal gains some advantages over the original HFE scheme with respect to the encryption speed and public key size.

Hot exciton relaxation in multiple layers CdSe/ZnSe self-assembled quantum dots separated by thick ZnSe barriers

International Nuclear Information System (INIS)

Eremenko, M; Budkin, G; Reznitsky, A

2015-01-01

We have studied PL and PLE spectra of two samples (A and B) of MBE grown CdSe/ZnSe asymmetric double quantum wells with different amount of deposited CdSe layers separated by 14 nm ZnSe barrier. It has been found that PLE spectra of the states forming short wavelength side of the PL spectra of both deep and shallow QWs of the sample A as well as that of deep QW of the sample B demonstrate oscillating structure in the spectral ranges corresponding to exciton states of self-assembled quantum dots only. Meanwhile PLE spectra of the short wavelength states of shallow QW the sample B revealed pronounced oscillating structure with energy period of ZnSe LO phonon under excitation with photons in a wide energy range both in the regions of quantum-dot states and in that of free states in the ZnSe barrier. In these spectra creating of excitons with kinetic energies more than 0.3 eV was observed which considerably exceed the exciton binding energy as well as LO phonon energy (both appr. 0.03 eV). It has been concluded that oscillating structure of the PLE spectra arises due to cascade relaxation of hot excitons. We discuss the model which explains these experimental findings. (paper)

Hot exciton relaxation in multiple layers CdSe/ZnSe self-assembled quantum dots separated by thick ZnSe barriers

Science.gov (United States)

Eremenko, M.; Budkin, G.; Reznitsky, A.

2015-11-01

We have studied PL and PLE spectra of two samples (A and B) of MBE grown CdSe/ZnSe asymmetric double quantum wells with different amount of deposited CdSe layers separated by 14 nm ZnSe barrier. It has been found that PLE spectra of the states forming short wavelength side of the PL spectra of both deep and shallow QWs of the sample A as well as that of deep QW of the sample B demonstrate oscillating structure in the spectral ranges corresponding to exciton states of self-assembled quantum dots only. Meanwhile PLE spectra of the short wavelength states of shallow QW the sample B revealed pronounced oscillating structure with energy period of ZnSe LO phonon under excitation with photons in a wide energy range both in the regions of quantum-dot states and in that of free states in the ZnSe barrier. In these spectra creating of excitons with kinetic energies more than 0.3 eV was observed which considerably exceed the exciton binding energy as well as LO phonon energy (both appr. 0.03 eV). It has been concluded that oscillating structure of the PLE spectra arises due to cascade relaxation of hot excitons. We discuss the model which explains these experimental findings.

Sample Set (SE): SE53 [Metabolonote[Archive

Lifescience Database Archive (English)

Full Text Available SE53 Covering chemical diversity of genetically-modified tomatoes using metabolomics...signature. We conclude that multi-platform metabolomics is an approach that is both sensitive and robust and

Sample Set (SE): SE10 [Metabolonote[Archive

Lifescience Database Archive (English)

Full Text Available SE10 Effect of phosphorus nutrition for cabbage metabolites Investigation of Brassi...ca oleracea var. capitata Hatukoi leaf metabolites. 3 growth conditions (high, low and no phosphorus nutrition

Sample Set (SE): SE31 [Metabolonote[Archive

Lifescience Database Archive (English)

Full Text Available SE31 Comparison of seed metabolites among eggplant fruit tissues Investigation of S...olanum melongena Senryounigou metabolites. 3 tissues (flesh, fruit, peel) data are examined. Takeshi Ara 1,

Sample Set (SE): SE28 [Metabolonote[Archive

Lifescience Database Archive (English)

Full Text Available SE28 Comparison of leaf metabolites among developmental stages of Hevea brasiliensi...s Investigation of Hevea brasiliensis leaf metabolites. 4 developmental stages and 6 replicates data are exa

Superconductivity in the ferecrystals (PbSe){sub 1.14}(NbSe{sub 2}){sub n}

Energy Technology Data Exchange (ETDEWEB)

Grosse, Corinna; Chiatti, Olivio; Fischer, Saskia F. [Novel Materials Group, Humboldt-Universitaet Berlin (Germany); Alemayehu, Matti B.; Falmbigl, Matthias; Johnson, David C. [Department of Chemistry, University of Oregon, Eugene, OR (United States)

2016-07-01

The ferecrystals (PbSe){sub 1.14}(NbSe{sub 2}){sub n} are artificially layered materials consisting of n NbSe{sub 2} single-layers stacked alternately with atomic double layers of PbSe. NbSe{sub 2} is a transition metal dichalcogenide with interesting electrical properties such as superconductivity and charge density waves. The influence of turbostratic disorder, a random rotation between the NbSe{sub 2} and PbSe layers, on the superconducting transition temperature has been unknown so far. We investigate the structural and temperature-dependent electrical properties of the ferecrystals (PbSe){sub 1.14}(NbSe{sub 2}){sub n} by means of scanning transmission electron microscopy, X-ray diffraction, in-plane resistivity and Hall measurements and compare them to those of analogous non-disordered misfit layer compound (MLC) polymorphs. We observe a superconducting transition in the resistivity of the ferecrystals. The transition temperatures are reduced by up to 55 % with respect to the analogous MLC polymorphs. This indicates that turbostratic disorder substantially weakens the electron-phonon coupling in (PbSe){sub 1.14}(NbSe{sub 2}){sub n}. We discuss the results of the structural and electrical properties of the ferecrystals with respect to their MLC analogues and also with respect to ultra-thin NbSe{sub 2} layers.

Synthesis and optical study of green light emitting polymer coated CdSe/ZnSe core/shell nanocrystals

Energy Technology Data Exchange (ETDEWEB)

Tripathi, S.K., E-mail: surya@pu.ac.in [Department of Physics, Center of Advanced Study in Physics, Panjab University, Chandigarh 160 014 (India); Sharma, Mamta [Department of Physics, Center of Advanced Study in Physics, Panjab University, Chandigarh 160 014 (India)

2013-05-15

Highlights: ► Synthesis of Polymer coated core CdSe and CdSe/ZnSe core/shell NCs. ► From TEM image, the spherical nature of CdSe and CdSe/ZnSe is obtained. ► Exhibiting green band photoemission peak at 541 nm and 549 nm for CdSe core and CdSe/ZnSe core/shell NCs. ► The shell thickness has been calculated by using superposition of quantum confinement energy model. - Abstract: CdSe/ZnSe Core/Shell NCs dispersed in PVA are synthesized by chemical method at room temperature. This is characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), UV/Vis spectra and photoluminescence spectroscopy (PL). TEM image shows the spherical nature of CdSe/ZnSe core/shell NCs. The red shift of absorption and emission peak of CdSe/ZnSe core/shell NCs as compared to CdSe core confirmed the formation of core/shell. The superposition of quantum confinement energy model is used for calculation of thickness of ZnSe shell.

Sample Set (SE): SE20 [Metabolonote[Archive

Lifescience Database Archive (English)

Full Text Available SE20 Arabidopsis thaliana leaf metabolite analysis for a software test Investigatio...es that were investigated to optimize the parameters of PowerGet software for better metabolite annotation i

Gestión del conocimiento y capital intelectual en la industria tequilera del estado de Jalisco

Directory of Open Access Journals (Sweden)

Marco Alberto Núñez Ramírez

2014-06-01

Full Text Available Estudios muestran que la gestión del conocimiento se asocia con el capital intelectual; sin embargo, no se tiene claro cómo se da dicha relación. El objetivo de la presente investigación es conocer el grado de asociación de la gestión del conocimiento y el capital intelectual. Se obtuvo como evidencia empírica 50 empresas tequileras del estado de Jalisco, México. Se encontraron niveles positivos y significativos de correlación entre las mencionadas variables; así como valores significativos de influencia de la gestión del conocimiento sobre el capital intelectual, a través del empleo de variables control como el tamaño de la empresa y área de comercialización; por medio de una investigación cuantitativa y correlacional, con un diseño no experimental, donde se empleó la correlación de Pearson, regresión múltiple y regresión jerárquica.

Sample Set (SE): SE18 [Metabolonote[Archive

Lifescience Database Archive (English)

Full Text Available in by Orbitrap MS and automated search engine Lipid Search A comprehensive and precise identification of pho...SE18 Global identification of phospholipid molecular species in mouse liver and bra

Electrochemical synthesis of nanostructured Se-doped SnS: Effect of Se-dopant on surface characterizations

International Nuclear Information System (INIS)

Kafashan, Hosein; Azizieh, Mahdi; Balak, Zohre

2017-01-01

Highlights: • Nanostructured SnS_1_-_xSe_x thin films were prepared by using electrodeposition method. • The XRD patterns obviously showed that the synthesized films were polycrystalline. • The PL spectra of SnS_1_-_xSe_x thin films showed four emission peaks. • The UV–vis spectra shows a variation in the optical band gap energy of SnS_1_-_xSe_x thin films from 1.22 to 1.65 eV. • SnS_1_-_xSe_x thin films would be suitable for use as absorber layers. - Abstract: SnS_1_-_xSe_x nanostructures with different Se-dopant concentrations were deposited on fluorine doped tin oxide (FTO) substrate through cathodic electrodeposition technique. The pH, temperature, applied potential (E), and deposition time remained were 2.1, 60 °C, −1 V, and 30 min, respectively. SnS_1_-_xSe_x nanostructures were characterized using X-ray diffraction (XRD), field emission scanning electron microcopy (FESEM), energy dispersive X-ray spectroscopy (EDX), room temperature photoluminescence (PL), and UV–vis spectroscopy. The XRD patterns revealed that the SnS_1_-_xSe_x nanostructures were polycrystalline with orthorhombic structure. FESEM showed various kinds of morphologies in SnS_1_-_xSe_x nanostructures due to Se-doping. PL and UV–vis spectroscopy were used to evaluate the optical properties of SnS_1_-_xSe_x thin films. The PL spectra of SnS_1_-_xSe_x nanostructures displayed four emission peaks, those are a blue, a green, an orange, and a red emission. UV–vis spectra showed that the optical band gap energy (E_g) of SnS_1_-_xSe_x nanostructures varied between 1.22–1.65 eV, due to Se-doping.

Updating Human Factors Engineering Guidelines for Conducting Safety Reviews of Nuclear Power Plants

International Nuclear Information System (INIS)

O'Hara, J.M.; Higgins, J.; Fleger, Stephen

2011-01-01

The U.S. Nuclear Regulatory Commission (NRC) reviews the human factors engineering (HFE) programs of applicants for nuclear power plant construction permits, operating licenses, standard design certifications, and combined operating licenses. The purpose of these safety reviews is to help ensure that personnel performance and reliability are appropriately supported. Detailed design review procedures and guidance for the evaluations is provided in three key documents: the Standard Review Plan (NUREG-0800), the HFE Program Review Model (NUREG-0711), and the Human-System Interface Design Review Guidelines (NUREG-0700). These documents were last revised in 2007, 2004 and 2002, respectively. The NRC is committed to the periodic update and improvement of the guidance to ensure that it remains a state-of-the-art design evaluation tool. To this end, the NRC is updating its guidance to stay current with recent research on human performance, advances in HFE methods and tools, and new technology being employed in plant and control room design. This paper describes the role of HFE guidelines in the safety review process and the content of the key HFE guidelines used. Then we will present the methodology used to develop HFE guidance and update these documents, and describe the current status of the update program.

Sample Set (SE): SE14 [Metabolonote[Archive

Lifescience Database Archive (English)

Full Text Available SE14 Effect of agricultural films for tomato fruit metabolites Investigation of Sol...anum lycopersicum fruit metabolites. 3 growth conditions (covered with normal or UV cut agricultural film or no agricultura