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INTRODUCTION: Heart failure (HF) is a clinical syndrome characterized by cardinal symptoms that may be accompanied by signs. It results from structural and/or functional abnormalities of the heart leading to elevated intracardiac pressures and/or inadequate cardiac output at rest and/or during exercise. The prevalence of iron deficiency and anemia justifies the current guidelines recommendation of screening. Genes HP, ACE, MTHFR, HFE, and CYBA are involved in oxidative mechanisms, iron metabolism, and hematologic homeostasis. This study investigates the contribution of variants Hp1/2 (HP), I/D (ACE), C677T (MTHFR), C282Y and H63D (HFE), and C242T (CYBA) to the development of HF, either independently or in epistasis. METHODS: We used a database of 389 individuals, 143 HF patients, and 246 healthy controls. Genotypes were characterized through PAGE electrophoresis, PCR, PCR-RFLP, and multiplex-ARMS. Data analysis was performed with the SPSS® 26.0 software (IBM Corp., Armonk, NY). RESULTS: We observed a significant association between the MTHFR gene and HF predisposition. The presence of allele T and genotype CT constituted risk, while genotype CC granted protection. Epistatic interactions revealed risk between genotype II of the ACE gene and genotypes CC (C282Y) or HH (H63D) of the HFE gene. Risk was also observed for interactions between genotype CC (CYBA)and genotypes 2-2 (HP), CT (MTHFR), or HH (HFE-H63D). CONCLUSION: We concluded that genes HP, ACE, MTHFR, HFE, and CYBA contribute to the susceptibility for HF, individually or in epistasis. This study contributes to the clarification of the role that genes involved in oxidative mechanisms and iron metabolism play in the physiopathology of HF. It is, therefore, a step forward in risk stratification and personalized medicine.
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Charge mediated magnetoelectric coupling mechanism in artificial multiferroics originates from interfacial charge modulation or ionic movement at a magnetic/dielectric interface. Despite the existence of several dielectric/ferroelectric systems that can be used in charge mediated artificial multiferroic systems, producing suitable systems with fast time responses still remains a challenge. Here we characterize the frequency response of stoichiometric and non-stoichiometric (low strain) Si 3 N 4 thin film membranes, which can potentially be used as the dielectric layer in magnetoelectric devices, to determine the impact of depletion layers, charge traps and defect mobility on the high frequency (up to 100 MHz) interfacial charge modulation via screening. We find that the dielectric/magnetoelectric properties are largely dominated by extrinsic doping due to point defects. In particular, we find that non-stoichiometric Si 3 N 4 has a dielectric behaviour that is dominated by charge traps and/or mobile ions. However, stoichiometric Si 3 N 4 membranes show a reversible response to the applied bias electric field consistent with a doped semiconductor behaviour; at high frequencies, the intrinsic dielectric behaviour is reached, indicating that it may be suitable for high frequency magnetoelectric device applications. Our results show that minimising the impact of defects on the dielectric properties of magnetoelectric heterostructures is an important prerequisite for obtaining a high frequency magnetoelectric response. Supplementary Information: The online version contains supplementary material available at 10.1007/s10853-022-07832-2.
