Publications by authors named "R Estephan"

Cutaneous T cell lymphoma (CTCL) is characterized by a background of chronic inflammation, where malignant CTCL cells escape immune surveillance. To study how microRNAs (miRs) regulate T-cell exhaustion, we performed miR sequencing analysis, qRT-PCR, and in situ hybridization on 45 primary CTCL samples, three healthy skin samples, and CTCL cell lines, identifying miR-155-5p, miR-130b-3p, and miR-21-3p. Moreover, miR-155-5p, miR-130b-3p, and miR-21-3p positively correlated with immune checkpoint gene expression in lesional skin samples and were enriched in the IL-6/Jak/signal transducer and activator of transcription signaling pathway by gene set enrichment analysis.

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Mast cells are associated with inflammation and fibrosis. Whether they protect against or contribute to renal fibrosis is unclear. Based on our previous findings that mast cells can express and secrete active renin, and that angiotensin (ANG II) is profibrotic, we hypothesized that mast cells play a critical role in tubulointerstitial fibrosis.

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Structural characterization of G protein-coupled receptors (GPCRs) is hindered by the inherent hydrophobicity, flexibility, and large size of these signaling proteins. Insights into conformational preferences and the three-dimensional (3D) structure of domains of these receptors can be obtained using polypeptide fragments of these proteins. Herein, we report the expression, purification, and biophysical characterization of a three-transmembrane domain-containing 131-residue fragment of the yeast α-factor receptor, Ste2p.

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Liver fatty acid-binding protein (LFABP) is a 14 kDa cytosolic polypeptide, differing from other family members in the number of ligand binding sites, the diversity of bound ligands, and the transfer of fatty acid(s) to membranes primarily via aqueous diffusion rather than direct collisional interactions. Distinct two-dimensional (1)H-(15)N nuclear magnetic resonance (NMR) signals indicative of slowly exchanging LFABP assemblies formed during stepwise ligand titration were exploited, without determining the protein-ligand complex structures, to yield the stoichiometries for the bound ligands, their locations within the protein binding cavity, the sequence of ligand occupation, and the corresponding protein structural accommodations. Chemical shifts were monitored for wild-type LFABP and an R122L/S124A mutant in which electrostatic interactions viewed as being essential to fatty acid binding were removed.

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Background: Renin released by ischemia/reperfusion from cardiac mast cells activates a local renin-angiotensin system (RAS). This exacerbates norepinephrine release and reperfusion arrhythmias (ventricular tachycardia and fibrillation), making RAS a new therapeutic target in myocardial ischemia.

Methods And Results: We investigated whether ischemic preconditioning (IPC) prevents cardiac RAS activation in guinea pig hearts ex vivo.

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