198 research outputs found
Fabrication and electrical characteristics of high-performance ZnO nanorod field-effect transistors
We report on fabrication and electrical characteristics of high-mobility field-effect transistors (FETs) using ZnO nanorods. For FET fabrications, single-crystal ZnO nanorods were prepared using catalyst-free metalorganic vapor phase epitaxy. Although typical ZnO nanorod FETs exhibited good electrical characteristics, with a transconductance of similar to140 nS and a mobility of 75 cm(2)/V s, the device characteristics were significantly improved by coating a polyimide thin layer on the nanorod surface, exhibiting a large turn-ON/OFF ratio of 10(4)-10(5), a high transconductance of 1.9 muS, and high electron mobility above 1000 cm(2)/V s. The role of the polymer coating in the enhancement of the devices is also discussed. (C) 2004 American Institute of Physics
Clinical Characteristics of Metastatic Tumors to the Ovaries
Approximately 5-30% of the ovarian cancers are metastatic malignancies. The prevalence of metastatic ovarian tumors varies with the incidence rates and spread patterns of primary malignancies. We evaluated the prevalence, pre- and postoperative characteristics of metastatic ovarian cancer in Korean women. We reviewed the records for 821 ovarian malignancies with pathological consultation from 1996-2006 and recorded patient demographical, radiological, histopathological, and survival data. The study included 112 cases of histologically confirmed metastatic ovarian cancer. Metastatic ovarian cancer accounted for 13.6% of all ovarian malignancy, primarily arising from the gastrointestinal tract. The preoperative detection rate with imaging was 75%, and none of the radiological or serological features were useful for differential diagnosis. In multivariate analysis for prognostic variables, the only significant factor was the primary tumor site (p=0.004). Furthermore, extensive resection increased survival for some patients. The differential diagnosis of metastatic ovarian cancer can be problematic, so multiple diagnostic approaches are necessary. The extent of cytoreductive surgery for this type of tumor must be decided on a case-by-case basis
SALM4 suppresses excitatory synapse development by cis-inhibiting trans-synaptic SALM3-LAR adhesion
Synaptic adhesion molecules regulate various aspects of synapse development, function and plasticity. These functions mainly involve trans-synaptic interactions and positive regulations, whereas cis-interactions and negative regulation are less understood. Here we report that SALM4, a member of the SALM/Lrfn family of synaptic adhesion molecules, suppresses excitatory synapse development through cis inhibition of SALM3, another SALM family protein with synaptogenic activity. Salm4-mutant (Salm4) mice show increased excitatory synapse numbers in the hippocampus. SALM4 cis-interacts with SALM3, inhibits trans-synaptic SALM3 interaction with presynaptic LAR family receptor tyrosine phosphatases and suppresses SALM3-dependent presynaptic differentiation. Importantly, deletion of Salm3 in Salm4 mice (Salm3, Salm4) normalizes the increased excitatory synapse number. These results suggest that SALM4 negatively regulates excitatory synapses via cis inhibition of the trans-synaptic SALM3-LAR adhesion. © The Author(s) 2016110101sciescopu
Snake fang-inspired stamping patch for transdermal delivery of liquid formulations
A flexible microneedle patch that can transdermally deliver liquid-phase therapeutics would enable direct use of existing, approved drugs and vaccines, which are mostly in liquid form, without the need for additional drug solidification, efficacy verification, and subsequent approval. Specialized dissolving or coated microneedle patches that deliver reformulated, solidified therapeutics have made considerable advances; however, microneedles that can deliver liquid drugs and vaccines still remain elusive because of technical limitations. Here, we present a snake fang-inspired microneedle patch that can administer existing liquid formulations to patients in an ultrafast manner (< 15 s). Rear-fanged snakes have an intriguing molar with a groove on the surface, which enables rapid and efficient infusion of venom or saliva into prey. Liquid delivery is based on surface tension and capillary action. The microneedle patch uses multiple open groove architectures that emulate the grooved fangs of rear-fanged snakes: Similar to snake fangs, the microneedles can rapidly and efficiently deliver diverse liquid-phase drugs and vaccines in seconds under capillary action with only gentle thumb pressure, without requiring a complex pumping system. Hydrodynamic simulations show that the snake fang-inspired open groove architectures enable rapid capillary force-driven delivery of liquid formulations with varied surface tensions and viscosities. We demonstrate that administration of ovalbumin and influenza virus with the snake fang-inspired microneedle patch induces robust antibody production and protective immune response in guinea pigs and mice
The First Case of Catheter-related Bloodstream Infection Caused by Nocardia farcinica
Nocardia farcinica is an emerging pathogen in immunocompromised hosts. Even though several species of Nocardia have been reported as causative pathogens of catheter-related blood stream infections (CRBSI), CRBSI caused by N. farcinica has not been reported. A 70-yr-old man with a tunneled central venous catheter (CVC) for home parenteral nutrition was admitted with fever for two days. Norcardia species was isolated from the blood through CVC and peripheral bloods and identified to N. farcinica by 16S rRNA and rpoB gene sequence analyses. This report emphasizes the rapid and correct identification of causative agents in infectious diseases in the selection of antimicrobial agents and the consideration of catheter removal
The First Very Long Baseline Interferometry Image of 44 GHz Methanol Maser with the KVN and VERA Array (KaVA)
We have carried out the first very long baseline interferometry (VLBI)
imaging of 44 GHz class I methanol maser (7_{0}-6_{1}A^{+}) associated with a
millimeter core MM2 in a massive star-forming region IRAS 18151-1208 with KaVA
(KVN and VERA Array), which is a newly combined array of KVN (Korean VLBI
Network) and VERA (VLBI Exploration of Radio Astrometry). We have succeeded in
imaging compact maser features with a synthesized beam size of 2.7
milliarcseconds x 1.5 milliarcseconds (mas). These features are detected at a
limited number of baselines within the length of shorter than approximately 650
km corresponding to 100 Mlambda in the uv-coverage. The central velocity and
the velocity width of the 44 GHz methanol maser are consistent with those of
the quiescent gas rather than the outflow traced by the SiO thermal line. The
minimum component size among the maser features is ~ 5 mas x 2 mas, which
corresponds to the linear size of ~ 15 AU x 6 AU assuming a distance of 3 kpc.
The brightness temperatures of these features range from ~ 3.5 x 10^{8} to 1.0
x 10^{10} K, which are higher than estimated lower limit from a previous Very
Large Array observation with the highest spatial resolution of ~ 50 mas. The 44
GHz class I methanol maser in IRAS 18151-1208 is found to be associated with
the MM2 core, which is thought to be less evolved than another millimeter core
MM1 associated with the 6.7 GHz class II methanol maser.Comment: 19 pages, 3 figure
Dlx5 specifically regulates Runx2 type II expression by binding to homeodomain-response elements in the Runx2 distal promoter
Two major isoforms of the Runx2 gene are expressed by alternative
promoter usage: Runx2 type I (Runx2-I) is derived from the
proximal promoter (P2), and Runx2 type II (Runx2-II) is produced
by the distal promoter (P1). Our previous results indicate that Dlx5
mediates BMP-2-induced Runx2 expression and osteoblast differentiation
(Lee, M.-H., Kim, Y-J., Kim, H-J., Park, H-D., Kang, A-R.,
Kyung, H.-M., Sung, J-H., Wozney, J. M., Kim, H-J., and Ryoo, H-M.
(2003) J. Biol. Chem. 278, 34387–34394). However, little is known of
the molecular mechanisms by which Dlx5 up-regulates Runx2
expression in BMP-2 signaling. Here, Runx2-II expression was
found to be specifically stimulated by BMP-2 treatment or by Dlx5
overexpression. In addition, BMP-2, Dlx5, and Runx2-II were found
to be expressed in osteogenic fronts and parietal bones of the developing
cranial vault and Runx2-I and Msx2 in the sutural mesenchyme.
Furthermore, Runx2 P1 promoter activity was strongly
stimulated by Dlx5 overexpression, whereas Runx2 P2 promoter
activity was not. Runx2 P1 promoter deletion analysis indicated that
the Dlx5-specific response is due to sequences between 756 and
342 bp of the P1 promoter, where three Dlx5-response elements
are located. Dlx5 responsiveness to these elements was confirmed
by gel mobility shift assay and site-directed mutagenesis. Moreover,
Msx2 specifically suppressed the Runx2 P1 promoter, and the
responsible region overlaps with that recognized by Dlx5. In summary,
Dlx5 specifically transactivates the Runx2 P1 promoter, and
its action on the P1 promoter is antagonized by Msx2.This work was supported by Grants 01-PJ1-PG1-01CH08-0001 and 01-PJ3-PG6-
01GN11-0002 from the Korea Health 21 R&D Project, Ministry of Health and Welfare,
Republic of Korea. The costs of publication of this article were defrayed in part by the
payment of page charges. This article must therefore be hereby marked advertisement
in accordance with 18 U.S.C. Section 1734 solely to indicate this fact
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