97 research outputs found
Multi-view Cross-Modality MR Image Translation for Vestibular Schwannoma and Cochlea Segmentation
In this work, we propose a multi-view image translation framework, which can
translate contrast-enhanced T1 (ceT1) MR imaging to high-resolution T2 (hrT2)
MR imaging for unsupervised vestibular schwannoma and cochlea segmentation. We
adopt two image translation models in parallel that use a pixel-level
consistent constraint and a patch-level contrastive constraint, respectively.
Thereby, we can augment pseudo-hrT2 images reflecting different perspectives,
which eventually lead to a high-performing segmentation model. Our experimental
results on the CrossMoDA challenge show that the proposed method achieved
enhanced performance on the vestibular schwannoma and cochlea segmentation.Comment: 9 pages, 4 figure
Serum cytokine profiles in healthy young and elderly population assessed using multiplexed bead-based immunoassays
<p>Abstract</p> <p>Background</p> <p>Lipid metabolites and cytokines, including chemokines and growth factors, are the key regulators of immune cell function and differentiation, and thus, dysregulation of these regulators is associated with various human diseases. However, previous studies demonstrating a positive correlation of cytokine levels with aging may have been influenced by various environmental factors and underlying diseases. Also, data regarding cytokine profiling in the elderly are limited to a small subset of cytokines.</p> <p>Methods</p> <p>We compared the profiles of 22 cytokines, including chemokines and growth factors, in a case-controlled study group of a gender-matched, healthy cohort of 55 patients over the age of 65 and 55 patients under the age of 45. Assessment of serum cytokine concentrations was performed using commercially-available multiplex bead-based sandwich immunoassays.</p> <p>Results</p> <p>Soluble CD40 ligand (sCD40L) and transforming growth factor alpha (TGF-Ī±) levels were significantly higher in the elderly patients, whereas granulocyte colony-stimulating factor (G-CSF), granulocyte-monocyte colony-stimulating factor (GM-CSF), and monocyte chemoattractant protein-1 (MCP-1) levels were significantly lower in the elderly patients. The partial correlation analysis demonstrating the correlation between cytokine levels when controlled for gender, systolic blood pressure, total cholesterol, HDL cholesterol, triglyceride, and serum creatinine levels further demonstrated that G-CSF, GM-CSF, and MCP-1 had significant negative correlations with age, whereas sCD40L and TGF-Ī± had significant positive correlations.</p> <p>Conclusions</p> <p>Future studies will focus on examining the significance of these age-related changes in circulating cytokines and other biological markers and their potential contribution to the development of different age-associated diseases.</p
The Interval Between Initiation of Anti-tuberculosis Treatment in Patients with Culture-positive Pulmonary Tuberculosis and Receipt of Drug-susceptibility Test Results
Although mycobacterial culture and the subsequent drug-susceptibility test (DST) for anti-tuberculosis (TB) drugs take several months to complete using solid media, there are no reports on the turnaround times of these tests under clinical conditions. The aim of this study was to determine the interval between initiation of anti-TB treatment and receipt of DST requested at an outpatient clinic. We prospectively enrolled patients with culture-positive pulmonary TB at Seoul National University Hospital from September 2002 to December 2004. Patients were followed up monthly. Mycobacterial cultures were done using Ogawa media at Seoul National University Hospital. DST were performed at the Korean Institute of Tuberculosis. Of the 104 patients enrolled, 54 were male. The median age was 41 yr. The median interval from initiation of anti-TB treatment to receipt of mycobacterial culture results by clinicians was 37 days (range, 0-89 days). The median interval from initiation of treatment to confirmation of DST by requesting clinicians was 80.5 days (range, 28-145 days). Clinicians only received the results of DST more than two months after initiation of treatment when they followed up patients monthly and mycobacterial culture was performed using solid media
A Synonymous Genetic Alteration of LMX1B in a Family with Nail-Patella Syndrome
The gene responsible for nail-patella syndrome, LMX1B, has recently been identified on chromosome 9q. Here we present a patient with nail-patella syndrome and an autosomal dominant pattern of inheritance. A 17-year-old girl visited our clinic for the evaluation and treatment of proteinuria. She had dystrophic nails, palpable iliac horns, and hypoplastic patellae. Electron microscopy of a renal biopsy showed irregular thickening of the glomerular basement membrane. A family history over three generations revealed five affected family members. Genetic analysis found a change of TCG to TCC, resulting in a synonymous alteration at codon 219 in exon 4 of the LMX1B gene in two affected family members. The same alteration was not detected in an unaffected family member. This is the first report of familial nail-patella syndrome associated with an LMX1B in Korea mutation, However, we can not completely rule out the possibility that the G-to-C change may be a single nucleotide polymorphism as this genetic mutation cause no alteration in amino acid sequence of LMX1B
Flexible, Highly Efficient All-Polymer Solar Cells
All-polymerĀ solarĀ cellsĀ have shown great potential asĀ flexibleĀ and portable power generators. These devices should offer good mechanical endurance with high power-conversion efficiency for viability in commercial applications. In this work, we developĀ highlyĀ efficientĀ and mechanically robustĀ all-polymerĀ solarĀ cellsĀ that are based on the PBDTTTPDĀ polymerĀ donor and the P(NDI2HD-T)Ā polymeracceptor. These systems exhibit high power-conversion efficiency of 6.64%. Also, the proposedĀ all-polymerĀ solarĀ cellsĀ have even better performance than the controlĀ polymer-fullerene devices with phenyl-C 61 -butyric acid methyl ester (PCBM) as the electron acceptor (6.12%). More importantly, ourĀ all-polymerĀ solarĀ cellsĀ exhibit dramatically enhanced strength and flexibility compared withpolymer/PCBM devices, with 60- and 470-fold improvements in elongation at break and toughness, respectively. The superior mechanical properties ofĀ all-polymerĀ solarĀ cellsĀ afford greater tolerance to severe deformations than conventionalĀ polymer-fullereneĀ solarĀ cells, making them much better candidates for applications inĀ flexibleĀ and portable devices.ope
The Incidence and Clinical Implication of Sputum with Positive Acid-Fast Bacilli Smear But Negative in Mycobacterial Culture in a Tertiary Referral Hospital in South Korea
Although it is not rare to find sputum that is positive acid-fast bacilli (AFB) smear but subsequent culture fails to isolate mycobacteria in clinical practice, the incidence and clinical implication of those sputa from new patients has not been clearly elucidated. The aim of this study was to determine the incidence and clinical implication of sputum with positive AFB smear but negative in mycobacterial culture. All sputa that were positive AFB smear requested during diagnostic work up for new patients visiting Seoul National University Hospital from 1 January 2005 through 31 December 2006 were included. Sputa producing a positive AFB smear but negative mycobacterial culture were classified into one of four categories: laboratory failure to isolate mycobacteria, false positive AFB smear, pathogen may show a positive AFB smear other than mycobacteria, and indeterminate results. Out of 447 sputa with a positive AFB smear, 29 (6.5%) failed to culture any organism. Among these 29 sputa, 18 were caused by laboratory failure to isolate mycobacteria, six were false positive smears, and five indeterminate. Although most sputum with a positive AFB smear but negative culture could be classified as a laboratory failure, clinicians should consider the possibility of false positive AFB smear
Human Metapneumovirus Infection in Hospitalized Children with Acute Respiratory Disease in Korea
Human metapneumovirus (hMPV) is a recently isolated virus, mostly associated with acute lower respiratory infection in children, of which symptoms are similar to those of respiratory syncytial virus (RSV) infection. The aim of our study was to determine the frequency of hMPV in hospitalized children with acute respiratory tract disease in Korea. Nasal aspirates from hospitalized children with respiratory infections under 15 yr old between December 2003 and February 2005 were included in the study. Each sample was analyzed for RSV, adenovirus, influenza virus A and B, and parainfluenza virus by indirect fluorescent assay (IFA). F-gene sequences were used for PCR for the detection and sequencing of hMPV. In total 381 samples, negative samples in which any viral pathogen could not be identified by IFA were 231 cases. hMPV was detected using reverse transcriptase-PCR (RT-PCR) in 28 of 231 (12.1%) children who were not infected with another respiratory viruses. The hMPV-infected children were diagnosed as having pneumonia, bronchiolitis, bronchial asthma exacerbation, croup, and upper respiratory tract infection. Most of the RT-PCR positive samples for hMPV were collected in winter season. These results suggest that hMPV may be a responsible pathogen causing acute respiratory tract infection in Korean children
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