Publications by authors named "Hyun Young Ahn"

Background: Only some studies have directly compared and analyzed the roles of activated partial thromboplastin time (aPTT) and activated clotting time (ACT) in coagulation monitoring during argatroban administration.

Objectives: This study aims to assess the correlation of argatroban dose with ACT and aPTT values and to identify the optimal coagulation test for argatroban dose adjustment.

Methods: We evaluated 55 patients on extracorporeal membrane oxygenation (ECMO) who received argatroban for more than 72 hours.

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Purpose: To assess the effect of continuous ketamine administration in patients admitted to medical and cardiac intensive care units (ICUs) and received mechanical ventilation support.

Methods: We conducted a retrospective cohort study between March 2012 and June 2020 at an academy-affiliated tertiary hospital. Adult patients who received mechanical ventilation support for over 24 h and continuous ketamine infusion for at least 8 h were included.

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Peroxidasin (PXDN) has been reported to crosslink the C-terminal non-collagenous domains of collagen IV (Col IV) by forming covalent sulfilimine bond. Here, we explored the physiological role of PXDN and its mechanism of action in endothelial cell survival and growth. Silencing of PXDN using siRNAs decreased cell proliferation without increase of the number of detached cells and decreased cell viability under serum-starved condition with increased fragmented nuclei and caspase 3/7 activity.

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Mesenchymal stromal/stem cells (MSCs) have the potential to differentiate into neuron-like cells under specific conditions and to secrete paracrine factors for neuroprotection and regeneration. Previously, Rho-kinase inhibitors have been reported to potentiate differentiation of rodent bone marrow MSCs into neuron-like cells induced by CoCl2 (HIF-1α activation-mimicking agent). Here, a strategy of priming MSCs with fasudil, a Rho-kinase inhibitor, was investigated using Wharton's jelly-derived MSCs (WJ-MSCs) to improve recovery in a rat model of intracranial hemorrhage (ICH).

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Mesenchymal stromal/stem cells derived from human Wharton's jelly (WJ-MSC) have emerged as a favorable source for autologous and allogenic cell therapy. Here, we characterized the proangiogenic features of WJ-MSCs and examined their ability to form functional vessels in in vivo models. First, we examined whether WJ-MSCs express endothelial and smooth muscle cell specific markers after culture in endothelial growth media.

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Endothelial progenitor cells (EPCs) are applied in the treatment of ischemic diseases. In ex vivo culture of human cord-blood derived EPCs, H1152, (S)-(+)-2-methyl-1-[(4-methyl-5-iso-quinolinyl) sulfonyl]-homopiperazine, markedly increased the number of EPCs. It also induced EPC migration, stimulated the phosphorylation of AKT, and reduced the expression of p27 in the EPCs.

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This study was undertaken to investigate the pregnancy outcomes in patients with systemic lupus erythematosus (SLE) and the appropriate timing of pregnancy. We performed a retrospective evaluation of 183 pregnancies with SLE at Catholic University Medical Center during the 13-year period from 1998 to 2010. Pregnancy outcomes were compared according to SLE characteristics.

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Rho kinase (ROCK) has been implicated in the regulation of vascular tone, endothelial dysfunction, inflammation and remodeling. Endothelial progenitor cells (EPC) have been proven to have the efficacy of therapeutic neovascularization in ischemia. However, the scarcity of EPCs limits cell therapy.

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Endothelial progenitor cells (EPCs) have been shown to have therapeutic potential in ischemic disease. However, the number of EPCs for cell therapy is limited. In this study, instead of the typical adherent culture method, we investigated a more efficient, clinically applicable nonadhesive expansion method for early EPCs using cord blood-derived cells to overcome rapid cellular senescence.

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Outgrowing endothelial progenitor-derived cells (EPDCs) originate from a novel hierarchy of endothelial progenitor cells. In this study, EPDCs isolated from human cord blood were examined for phenotype and functional features upon aging. Young or aged EPDCs were similar to human umbilical vein endothelial cells (HUVECs), in exhibiting typical endothelial phenotypes.

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Circulating endothelial progenitor cells (EPCs) contribute to neovascularization in tumor or ischemic tissues by multi-step events, including adhesion, migration, chemoattraction, and differentiation to endothelial cells. Anti-angiogenic RGD-peptides have been shown to directly induce apoptosis in human umbilical vein endothelial cells (HUVECs) and T cells. Here, we examined the effects of RGD-peptides on EPCs in terms of adhesive differentiation and apoptosis.

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Congenital diaphragmatic hernia (CDH) is often associated with major anomalies and chromosomal abnormalities. Chromosomal abnormalities are usually detected in 9.5% to 34% of fetuses with CDH prenatally diagnosed and the defect has also been reported in association with multiple syndromes such as Pallister-Killian syndrome, Fryns syndrome, Di George syndrome and Apert syndrome.

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Introduction: Uterine arteriovenous malformations are very rare and potentially life-threatening. They can present with menorrhagia, postpartum bleeding, postmenopausal bleeding, an asymptomatic mass, or congestive heart failure.

Case Report: We present a 37-year-old woman with massive uterine bleeding that started abruptly 3 weeks after D and C and was found to be due to arteriovenous malformations.

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We report the imaging findings in a case of fetal lymphangioma involving the retroperitoneum and right lower extremity, and diagnosed by ultrasonography and magnetic resonance (MR) imaging at 26 weeks of gestation. Prenatal ultrasonograms and T2-weighted single-shot fast spin-echo MR images clearly revealed an extensive, multilocular cystic mass with internal hemorrhage in the retroperitoneum extending to the lower extremity.

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