21 research outputs found
Sequential Magnetic Resonance Imaging Finding of Intramedullary Spinal Cord Abscess including Diffusion Weighted Image: a Case Report
Intramedullary spinal cord abscess (ISCA) is a rare infection of the central nervous system. We describe the magnetic resonance imaging (MRI) findings, including the diffusion-weighted imaging (DWI) findings, of ISCA in a 78-year-old man. The initial conventional MRI of the thoracic spine demonstrated a subtle enhancing nodule accompanied by significant edema. On the follow-up MRI after seven days, the nodule appeared as a ring-enhancing nodule. The non-enhancing central portion of the nodule appeared hyperintense on DWI with a decreased apparent diffusion coefficient (ADC) value on the ADC map. We performed myelotomy and surgical drainage, and thick, yellowish pus was drained
A More Appropriate Cardiac Troponin T Level That Can Predict Outcomes in End-Stage Renal Disease Patients with Acute Coronary Syndrome
Purpose: Cardiac troponin T (cTnT), a useful marker for diagnosing acute myocardial infarction (AMI) in the general population, is significantly higher than the usual cut-off value in many end-stage renal disease (ESRD) patients without clinically apparent evidence of AMI. The aim of this study was to evaluate the clinical usefulness of cTnT in ESRD patients with acute coronary syndrome (ACS).
Materials and methods: Two hundred eighty-four ESRD patients with ACS were enrolled between March 2002 and February 2008. These patients were followed until death or June 2009. Medical records were reviewed retrospectively. The cut-off value of cTnT for AMI was evaluated using a receiver operating characteristic (ROC) curve. We calculated Kaplan-Meier survival curves, and potential outcome predictors were determined by Cox proportional hazard analysis.
Results: AMIs were diagnosed in 40 patients (14.1%). The area under the curve was 0.98 in the ROC curve (p<0.001; 95% CI, 0.95-1.00). The summation of sensitivity and specificity was highest at the initial cTnT value of 0.35 ng/mL (sensitivity, 0.95; specificity, 0.97). Survival analysis showed a statistically significant difference in all-cause and cardiovascular mortalities for the group with an initial cTnT ≥0.35 ng/mL compared to the other groups. Initial serum cTnT concentration was an independent predictor for mortality.
Conclusion: Because ESRD patients with an initial cTnT concentration ≥0.35 ng/mL have a poor prognosis, it is suggested that urgent diagnosis and treatment be indicated in dialysis patients with ACS when the initial cTnT levels are ≥0.35 ng/mL.ope
Korean Red Ginseng Saponin Fraction Rich in Ginsenoside-Rb1, Rc and Rb2 Attenuates the Severity of Mouse Collagen-Induced Arthritis
Study on the Electrochemical Kinetics of Manganese Dioxide/Multiwall Carbon Nanotube Composite by Voltammetric Charge Analysis
Electrochemical properties of MnO2/multiwall carbon nanotube (MWCNT) composites were investigated by using cavity microelectrodes (CME). Electrochemical kinetics of the MnO2/MWCNT composites were studied by analyzing the scan rate dependence of voltammetric charge, which was measured by cyclic voltammetry (CV) at various scan rates ranging from 20 mV s&#8722;1 to 1000 mV s&#8722;1. Based on several mathematical models, the relationship between voltammetric charge and scan rate was interpreted systematically. At slow scan rates, ion diffusion in MnO2 dominantly determined the rate of the overall electrochemical process. However, the faradaic reaction of Mn3+/Mn4+ at the MnO2 surface competed with mass transfer in terms of kinetics when the potential scan rate was higher than 400 mV s&#8722;1.close
Functional role of the Frizzled linker domain in the Wnt signaling pathway
The linker domain of Frizzled receptors has a varying effect on the functional levels of canonical and non-canonical Wnt signaling, with FZD chimeras influencing the binding of Wnt proteins and the recruitment of proteins regulating downstream signaling. The Wnt signaling pathway plays a critical role in the developmental and physiological processes of metazoans. We previously reported that the Frizzled4 (FZD4) linker domain plays an important role in Norrin binding and signaling. However, the question remains whether the FZD linker contributes to Wnt signaling in general. Here, we show that the FZD linker is involved in Wnt binding and affects downstream Wnt signaling. A FZD4 chimera, in which the linker was swapped with that of the non-canonical receptor FZD6, impairs the binding with WNT3A and suppresses the recruitment of LRP6 and Disheveled, resulting in reduced canonical signaling. A similar effect was observed for non-canonical signaling. A FZD6 chimera containing the FZD1 linker showed reduced WNT5A binding and impaired signaling in ERK, JNK, and AKT mediated pathways. Altogether, our results suggest that the FZD linker plays an important role in specific Wnt binding and intracellular Wnt signaling.N
In Situ Synthesis of Three-Dimensional Self-Assembled Metal Oxide–Reduced Graphene Oxide Architecture
The fabrication of self-assembled,
three-dimensional (3-D) graphene
structures is recognized as a powerful technique for integrating various
nanostructured building blocks into macroscopic materials. In this
way, nanoscale properties can be harnessed to provide innovative functionalities
of macroscopic devices with hierarchical microstructures. To this
end, we report on the fabrication of a three-dimensional (3-D) metal
oxide (MO)–reduced graphene oxide (RGO) architecture by controlling
the reduction conditions of graphene oxide. In this structure, SnO<sub>2</sub> nanoparticles with dimensions of 2–3 nm are uniformly
anchored and supported on a 3-D RGO structure. The resulting composite
exhibits excellent rate capability as a binder-free electrode and
shows great potential for use in Li-ion batteries. Furthermore, the
proposed reduction synthesis can also be applied to the study of the
synergetic properties of other 3-D MO–RGO architectures
Breast Tissue Restoration after the Partial Mastectomy Using Polycaprolactone Scaffold
As breast conserving surgery increases in the surgical treatment of breast cancer, partial mastectomy is also increasing. Polycaprolactone (PCL) is a polymer that is used as an artifact in various parts of the human body based on the biocompatibility and mechanical properties of PCL. Here, we hypothesized that a PCL scaffold can be utilized for the restoration of breast tissue after a partial mastectomy. To demonstrate the hypothesis, a PCL scaffold was fabricated by 3D printing and three types of spherical PCL scaffold including PCL scaffold, PCL scaffold with collagen, and the PCL scaffold with breast tissue fragment were implanted in the rat breast defect model. After 6 months of implantation, the restoration of breast tissue was observed in the PCL scaffold and the expression of collagen in the PCL scaffold with collagen was seen. The expression of TNF-α was significantly increased in the PCL scaffold, but the expression of IL-6 showed no significant difference in all groups. Through this, it showed the possibility of using it as a method to conveniently repair tissue defects after partial mastectomy of the human body
Korean Red Ginseng Saponin Fraction Rich in Ginsenoside-Rb1, Rc and Rb2 Attenuates the Severity of Mouse Collagen-Induced Arthritis
Despite a multitude of reports on anti-inflammatory properties of ginseng extracts or individual ginsenosides, data on antiarthritic effect of ginseng saponin preparation with mixed ginsenosides is limited. On the other hand, a combined therapy of safe and inexpensive plant-derived natural products such as ginsenosides can be considered as an alternative to treat arthritis. Our previous in vitro data displayed a strong anti-inflammatory action of red ginseng saponin fraction-A (RGSF-A). We, herein, report a marked antiarthritic property of RGSF-A rich in ginsenoside Rb1, Rc, and Rb2. Collagen-induced arthritic (CIA) mice were treated with RGSF-A or methotrexate (MTX) for 5 weeks. Joint pathology, serum antibody production and leukocye activation, cytokine production in the circulation, lymph nodes, and joints were examined. RGSF-A markedly reduced severity of arthritis, cellular infiltration, and cartilage damage. It suppressed CD3+/CD69+, CD4+/CD25+, CD8+ T-cell, CD19+, B220/CD23+ B-cell, MHCII+/CD11c+, and Gr-1+/CD11b+ cell activations. It further suppressed anti-CII- or anti-RF-IgG/IgM, TNF-α, IL-1β, IL-17, and IL-6 secretions but stimulated IL-10 levels in the serum, joint, or splenocyte. RGSF-A attenuated arthritis severity, modified leukocyte activations, and restored cytokine imbalances, suggesting that it can be considered as an antiarthritic agent with the capacity to ameliorate the immune and inflammatory responses in CIA mice
Spray-Assisted Deep-Frying Process for the In Situ Spherical Assembly of Graphene for Energy-Storage Devices
To take full advantage of graphene
in macroscale devices, it is
important to integrate two-dimensional graphene nanosheets into a
micro/macrosized structure that can fully utilize graphene’s
nanoscale characteristics. To this end, we developed a novel spray-assisted
self-assembly process to create a spherically integrated graphene
microstructure (graphene microsphere) using a high-temperature organic
solvent in a manner reminiscent of deep-frying. This graphene microsphere
improves the electrochemical performance of supercapacitors, in contrast
to nonassembled graphene, which is attributed to its structural and
pore characteristics. Furthermore, this synthesis method can also
produce an effective graphene-based hybrid microsphere structure,
in which Si nanoparticles are efficiently entrapped by graphene nanosheets
during the assembly process. When used in a Li-ion battery, this material
can provide a more suitable framework to buffer the considerable volume
change that occurs in Si during electrochemical lithiation/delithiation,
thereby improving cycling performance. This simple and versatile self-assembly
method is therefore directly relevant to the future design and development
of practical graphene-based electrode materials for various energy-storage
devices