3,873 research outputs found
Significance of EpCAM and TROP2 expression in non-small cell lung cancer
<p>Abstract</p> <p>Background</p> <p>The tumor-associated calcium signal transducer (<it>TACSTD</it>) genes, originally designated epithelial cell adhesion molecule (EpCAM) and TROP2, represent true oncogenes. Little is known about EpCAM and TROP2 gene expression in non-small cell lung carcinoma (NSCLC). This study evaluated EpCAM and TROP2 protein expression and clinicopathologic significance in cases of NSCLC.</p> <p>Methods</p> <p>Tissue microarray blocks acquired from 164 cases of NSCLC, including 100 cases of adenocarcinoma (AdC) and 64 of squamous cell carcinoma (SCC), were examined by immunohistochemical staining for EpCAM, and TROP2. The results were correlated with clinicopathologic data.</p> <p>Results</p> <p>EpCAM and TROP2 were significantly overexpressed in SCC than in AdC (<it>P </it>< 0.01). In AdC, EpCAM overexpression was closely related to sex, histologic grade, pathologic T stage, pathologic N stage, and TNM stage, and TROP2 overexpression was only related to histologic grade (<it>P </it>< 0.05, respectively). In SCC, correlations were evident between EpCAM overexpression and TNM stage (<it>P </it>= 0.01), and between TROP2 overexpression and pathologic T stage (<it>P </it>= 0.02). EpCAM overexpression showed no significance with overall survival in AdC and SCC patients. However, TROP2 overexpression in AdC had a positive influence on overall survival (<it>P </it>= 0.02) and disease-free survival (<it>P </it>= 0.03). In particular, AdC patients with stage II or III showed better overall survival (<it>P </it>= 0.05) and disease-free survival (<it>P </it>= 0.04).</p> <p>Conclusions</p> <p>While EpCAM and TROP2 show weak and non-complete membranous staining in normal bronchial epithelium and pneumocyte, their complete membranous expression in carcinoma suggests their role in carcinogenesis. EpCAM and TROP2 were more frequently overexpressed in SCC. EpCAM overexpression had no prognostic value in this study, but TROP2 overexpression showed better survival in AdC patients and might be a better prognostic marker in advanced stage AdC.</p
CLINICAL ASSESSMENT OF THE ASSOCIATION BETWEEN MICROALBUMINURIA AND PREDICTORS OF ATHEROSCLEROSIS IN PATIENTS WITH EARLY UNTREATED TYPE 2 DIABETES OR ESSENTIAL HYPERTENSION
Paleoparasitological Studies on Mummies of the Joseon Dynasty, Korea
Paleoparasitology is the application of conventional or molecular investigative techniques to archeological samples in order to reveal parasitic infection patterns among past populations. Although pioneering studies already have reported key paleoparasitological findings around the world, the same sorts of studies had not, until very recently, been conducted in sufficient numbers in Korea. Mummified remains of individuals dating to the Korean Joseon Dynasty actually have proved very meaningful to concerned researchers, owing particularly to their superb preservation status, which makes them ideal subjects for paleoparasitological studies. Over the past several years, our study series on Korean mummies has yielded very pertinent data on parasitic infection patterns prevailing among certain Joseon Dynasty populations. In this short review, we summarized the findings and achievements of our recent paleoparasitological examinations of Joseon mummies and discussed about the prospects for future research in this vein
I-gel as a first-line airway device in the emergency room for patients with out-of-hospital cardiac arrest
Aim. The optimal method for advanced airway management during cardiac arrest remains controversial. Most patients with out-of-hospital cardiac arrest (OHCA) in Korea are managed with a bag-valve mask by paramedics, while physicians perform advanced airway management in emergency departments (ED). Endotracheal intubation (ETI) has a risk of failure at the first attempt. By contrast, I-gel, a supraglottic airway device, is easier to insert than an endotracheal tube and shows a higher first-attempt success rate than ETI in out-of-hospital settings by paramedics in the United States. We reviewed the use of ETI and I-gel by ED physicians to assess the first attempt success rate in a hospital setting.
Methods. We conducted a retrospective chart review of patients with non-traumatic OHCA who were managed with either ETI using a Macintosh laryngoscope, or I-gel in the ED of Korean hospital from January 2012 to January 2014.
Results. Of 322 adult patients with non-traumatic OHCA, 160 received I-gel and 162 received ETI. The first-attempt success rate was higher in the I-gel group (96.9%) than in the ETI group (84.6%, p < 0.001). The time from arrival to obtaining advanced airway management was shorter in the I-gel group than in the ETI group.
Conclusions. I-gel showed a better first-attempt success rate and shorter insertion time compared with ETI when performed by physicians in a hospital setting
Analysis Method for Determining Optimal Synthetic Aperture Time Using Estimated Range and Doppler Cone Angle at the Center of Synthetic Aperture Length
Synthetic aperture time (SAT) is a crucial component for acquiring high-quality synthetic aperture radar images with an excellent target cross-range resolution. SAT is analyzed using the range and Doppler cone angle at the center of the synthetic aperture length (SAL). However, in a real flight mission setting, only the range and Doppler cone angle at the SALās starting point are determined. Therefore, we present a method for estimating the range and Doppler cone angle at the center of the SAL to calculate an accurate SAT that is suitable for the spatial resolution of the assigned mission. We performed an iterative analysis of SAT at the range and Doppler cone angle at the starting point of the SAL (original SAT) and at the center of the SAL (proposed SAT). Consequently, the proposed SAT decreased by 0.69%ā16.14% compared to the original SAT at a resolution of 0.1ā3.0 m
Refraction traveltime tomography using damped monochromatic wavefield
For complicated earth models, wave-equationābased
refraction-traveltime tomography is more accurate than
ray-based tomography but requires more computational
effort. Most of the computational effort in traveltime
tomography comes from computing traveltimes
and their FrĀ“echet derivatives, which for ray-based
methods can be computed directly. However, in most
wave-equation traveltime-tomography algorithms, the
steepest descent direction of the objective function
is computed by the backprojection algorithm, without
computing a Fr Ā“echet derivative directly.
We propose a new wave-based refraction-traveltimeā
tomography procedure that computes FrĀ“echet derivatives
directly and efficiently. Our method involves solving
a damped-wave equation using a frequency-domain,
finite-element modeling algorithm at a single frequency
and invoking the reciprocity theorem. A damping factor,
which is commonly used to suppress wraparound
effects in frequency-domain modeling, plays the role
of suppressing multievent wavefields. By limiting the
wavefield to a single first arrival, we are able to extract
the first-arrival traveltime from the phase term
without applying a time window. Computing the partial
derivative of the damped wave-equation solution
using the reciprocity theorem enables us to compute
the Fr Ā“echet derivative of amplitude, as well as that of
traveltime, with respect to subsurface parameters. Using
the Marmousi-2 model, we demonstrate numerically
that refraction traveltime tomography with large-offset
data can be used to provide the smooth initial velocity
model necessary for prestack depth migration.This work was financially supported by the National Laboratory
Project of the Ministry of Science and Technology
and the Brain Korea 21 project of the Ministry of Education.
We are also grateful to Prof. K. J. Marfurt of the University
of Houston and Dr. M. Schoenberger for editing our
manuscript
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Differential Change in the Prevalence of the Ascaris, Trichuris and Clonorchis infection Among Past East Asian Populations.
As we learn more about parasites in ancient civilizations, data becomes available that can be used to see how infection may change over time. The aim of this study is to assess how common certain intestinal parasites were in China and Korea in the past 2000 years, and make comparisons with prevalence data from the 20th century. This allows us to go on to investigate how and why changes in parasite prevalence may have occurred at different times. Here we show that Chinese liver fluke (Clonorchis sinensis) dropped markedly in prevalence in both Korea and China earlier than did roundworm (Ascaris lumbricoides) and whipworm (Trichuris trichiura). We use historical evidence to determine why this was the case, exploring the role of developing sanitation infrastructure, changing use of human feces as crop fertilizer, development of chemical fertilizers, snail control programs, changing dietary preferences, and governmental public health campaigns during the 20th century
Homer 2 tunes G proteinācoupled receptors stimulus intensity by regulating RGS proteins and PLCĪ² GAP activities
Homers are scaffolding proteins that bind G proteinācoupled receptors (GPCRs), inositol 1,4,5-triphosphate (IP3) receptors (IP3Rs), ryanodine receptors, and TRP channels. However, their role in Ca2+ signaling in vivo is not known. Characterization of Ca2+ signaling in pancreatic acinar cells from Homer2ā/ā and Homer3ā/ā mice showed that Homer 3 has no discernible role in Ca2+ signaling in these cells. In contrast, we found that Homer 2 tunes intensity of Ca2+ signaling by GPCRs to regulate the frequency of [Ca2+]i oscillations. Thus, deletion of Homer 2 increased stimulus intensity by increasing the potency for agonists acting on various GPCRs to activate PLCĪ² and evoke Ca2+ release and oscillations. This was not due to aberrant localization of IP3Rs in cellular microdomains or IP3R channel activity. Rather, deletion of Homer 2 reduced the effectiveness of exogenous regulators of G proteins signaling proteins (RGS) to inhibit Ca2+ signaling in vivo. Moreover, Homer 2 preferentially bound to PLCĪ² in pancreatic acini and brain extracts and stimulated GAP activity of RGS4 and of PLCĪ² in an in vitro reconstitution system, with minimal effect on PLCĪ²-mediated PIP2 hydrolysis. These findings describe a novel, unexpected function of Homer proteins, demonstrate that RGS proteins and PLCĪ² GAP activities are regulated functions, and provide a molecular mechanism for tuning signal intensity generated by GPCRs and, thus, the characteristics of [Ca2+]i oscillations
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