We investigate the degradation path of MAPbI3 (MA=methylammonium) films over flat TiO2 substrates at room temperature by means of X-ray diffraction, spectroscopic ellipsometry, X-ray photoelectron spectroscopy, and high-resolution transmission electron microscopy. The degradation dynamics is found to be similar in air and under vacuum conditions, which leads to the conclusion that the occurrence of intrinsic thermodynamic mechanisms is not necessarily linked to humidity. The process has an early stage, which drives the starting tetragonal lattice in the direction of a cubic atomic arrangement.
View Article and Find Full Text PDFThe role of chloride in the MAPbI3-xClx perovskite is still limitedly understood, albeit subjected of much debate. Here, we present a combined angle-resolved X-ray photoelectron spectroscopy (AR-XPS) and first-principles DFT modeling to investigate the MAPbI3-xClx/TiO2 interface. AR-XPS analyses carried out on ad hoc designed bilayers of MAPbI3-xClx perovskite deposited onto a flat TiO2 substrate reveal that the chloride is preferentially located in close proximity to the perovskite/TiO2 interface.
View Article and Find Full Text PDFNext-generation sequencing has greatly improved our knowledge of the mammalian transcriptome, identifying thousands of non-coding RNAs (ncRNAs), which are RNAs that rather than translate for proteins, have regulatory functions. Perhaps unsurprisingly, dysregulation of individual ncRNAs has been associated with the development of pathologies, including of the cardiovascular system. The best-characterized group of ncRNAs is represented by the short, highly conserved RNAs named microRNAs (miRNAs).
View Article and Find Full Text PDFIn this paper we report the synthesis and characterization of biocompatible multi-functional magnetic nanoparticles (MNPs) able to enhance the intracellular transport of N-methylated drugs. The FeO magnetic core was first functionalized with a mixed monolayer consisting of two different phosphonic acids having terminal acetylenic and amino groups, which provide an active platform for further functionalization with organic molecules. Then, a tetraphosphonate cavitand receptor (Tiiii) bearing an azide moiety and the N-hydroxysuccinimide (NHS) activated forms of poly(ethylene glycol) (PEG), folic acid (FA) and carboxy-X-rhodamine (Rhod) were covalently anchored on alkyne and amine moieties respectively, through 1,3-dipolar cycloaddition and EDC/NHS coupling reactions.
View Article and Find Full Text PDFNat Rev Cardiol
August 2015
The regulatory networks governing gene expression in cardiomyocytes are under intense investigation, not least because dysregulation of the gene programme has a fundamental role in the development of a failing myocardium. Epigenetic modifications and functional non-protein-coding RNAs (ncRNAs) are important contributors to this process. The epigenetic modifications that regulate transcription comprise post-translational changes to histones-the proteins around which DNA is wound-as well as modifications to cytosine residues on DNA.
View Article and Find Full Text PDFBackground: Lone atrial flutter (AFL) and atrial fibrillation (AF) are common and sometimes consequential cardiac conduction disorders with a strong heritability, as underlined by recent genome-wide association studies that identified genetic modifiers. Follow-up family-based genetic analysis also identified Mendelian transmission of disease alleles. Three affected members were exome-sequenced for the identification of potential causative mutations, which were subsequently validated by direct sequencing in the other 3 affected members.
View Article and Find Full Text PDFMicroRNAs (miRNAs) are small, non-coding, RNA molecules approximately 22 nucleotides in length which act as post-transcriptional regulators of gene expression. Individual miRNAs have been shown to regulate the expression of multiple genes. Conversely, the expression of individual genes can be regulated by multiple miRNAs.
View Article and Find Full Text PDFRationale: The miR-143/145 cluster is highly expressed in smooth muscle cells (SMCs), where it regulates phenotypic switch and vascular homeostasis. Whether it plays a role in neighboring endothelial cells (ECs) is still unknown.
Objective: To determine whether SMCs control EC functions through passage of miR-143 and miR-145.
Purpose Of Review: In this review, we summarize the basic principles underlying the therapeutic use of nonprotein coding (nc)RNAs, such as microRNA (miRNA) and long noncoding RNA, in the cardiovascular field, focusing, where possible, on recent advances that may lead to translation to the clinic for heart failure.
Recent Findings: The number of individual miRNAs associated with a given aspect of heart disease is increasing rapidly, as is the data on miRNA profiles in normal and diseased myocardium. Less is known on the role of long noncoding RNA, and to date only a few have been studied in the heart.
Background: Thiazide diuretics have been recommended as a first-line antihypertensive treatment, although the choice of 'the right drug in the individual essential hypertensive patient' remains still empirical. Essential hypertension is a complex, polygenic disease derived from the interaction of patient's genetic background with the environment. Pharmacogenomics could be a useful tool to pinpoint gene variants involved in antihypertensive drug response, thus optimizing therapeutic advantages and minimizing side effects.
View Article and Find Full Text PDFRNAs not encoding proteins have gained prominence over the last couple of decades as fundamental regulators of cellular function. Not surprisingly, their dysregulation is increasingly being linked to pathology. Here, we review recent reports investigating the pathophysiological relevance of this species of RNA for the cardiovascular system, concentrating mainly on recent findings on long noncoding RNAs and microRNAs in cardiac hypertrophy and failure.
View Article and Find Full Text PDFCurr Opin Nephrol Hypertens
March 2015
Purpose Of Review: Contrast-induced acute kidney injury (CI-AKI) is an impairment of renal function following contrast media administration in the absence of an alternative cause. It represents a powerful predictor of poor early and late outcomes. Here, we review the major strategies to prevent CI-AKI.
View Article and Find Full Text PDFBeilstein J Nanotechnol
December 2014
Free 4-undecenoxyphthalocyanine molecules were covalently bonded to Si(100) and porous silicon through thermic hydrosilylation of the terminal double bonds of the undecenyl chains. The success of the anchoring strategy on both surfaces was demonstrated by the combination of X-ray photoelectron spectroscopy with control experiments performed adopting the commercially available 2,3,9,10,16,17,23,24-octakis(octyloxy)-29H,31H-phthalocyanine, which is not suited for silicon anchoring. Moreover, the study of the shape of the XPS N 1s band gave relevant information on the interactions occurring between the anchored molecules and the substrates.
View Article and Find Full Text PDFEpigenetic changes on DNA and chromatin are implicated in cell differentiation and organogenesis. For the heart, distinct histone methylation profiles were recently linked to stage-specific gene expression programs during cardiac differentiation in vitro. However, the enzymes catalyzing these modifications and the genes regulated by them remain poorly defined.
View Article and Find Full Text PDFBackground: LMNA/C mutations have been linked to the premature aging syndrome Hutchinson's progeria, dilated cardiomyopathy 1A, skeletal myopathies (such as the autosomal dominant variant of Emery-Dreifuss muscular dystrophy and limb-girdle muscular dystrophy), Charcot-Marie-Tooth disorder type 2B1, mandibuloacral dysplasia, autosomal dominant partial lipodystrophy, and axonal neuropathy. Atrioventricular block (AVB) can be associated with several cardiac disorders and it can also be a highly heritable, primitive disease. One of the most common pathologies associated with AVB is dilated cardiomyopathy (DCM), which is characterized by cardiac dilatation and reduced systolic function.
View Article and Find Full Text PDFIschaemic heart disease (IHD) remains the leading cause of death and disability worldwide. As a result, novel therapies are still needed to protect the heart from the detrimental effects of acute ischaemia-reperfusion injury, in order to improve clinical outcomes in IHD patients. In this regard, although a large number of novel cardioprotective therapies discovered in the research laboratory have been investigated in the clinical setting, only a few of these have been demonstrated to improve clinical outcomes.
View Article and Find Full Text PDFBalanced control of neural progenitor maintenance and neuron production is crucial in establishing functional neural circuits during brain development, and abnormalities in this process are implicated in many neurological diseases. However, the regulatory mechanisms of neural progenitor homeostasis remain poorly understood. Here, we show that mammalian target of rapamycin (mTOR) is required for maintaining neural progenitor pools and plays a key role in mediating glycogen synthase kinase 3 (GSK3) signaling during brain development.
View Article and Find Full Text PDFBackground: Exposure to subclinical levels of lipopolysaccharide (LPS) occurs commonly and is seemingly well tolerated. However, recurrent LPS exposure induces cardiac fibrosis over 2 to 3 months in a murine model, not mediated by the renin-angiotensin system. Subclinical LPS induces cardiac fibrosis by unique mechanisms.
View Article and Find Full Text PDFMicroRNAs (miRNAs) control cell cycle progression by targeting the transcripts encoding for cyclins, CDKs and CDK inhibitors, such as p27(KIP1) (p27). p27 expression is controlled by multiple transcriptional and posttranscriptional mechanisms, including translational inhibition by miR-221/222 and posttranslational regulation by the SCF(SKP2) complex. The oncosuppressor activity of miR-340 has been recently characterized in breast, colorectal and osteosarcoma tumor cells.
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