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1.  Study of InN epitaxial films and nanorods grown on GaN template by RF-MOMBE 
Nanoscale Research Letters  2012;7(1):468.
This paper reports on high-quality InN materials prepared on a GaN template using radio-frequency metalorganic molecular beam epitaxy. We also discuss the structural and electro-optical properties of InN nanorods/films. The X-ray diffraction peaks of InN(0002) and InN(0004) were identified from their spectra, indicating that the (0001)-oriented hexagonal InN was epitaxially grown on the GaN template. Scanning electron microscopic images of the surface morphology revealed a two-dimensional growth at a rate of approximately 0.85 μm/h. Cross-sectional transmission electron microscopy images identified a sharp InN/GaN interface and a clear epitaxial orientation relationship of [0001]InN // [0001]GaN and ( 2¯110)InN // ( 2¯110)GaN. The optical properties of wurtzite InN nanorods were determined according to the photoluminescence, revealing a band gap of 0.77 eV.
doi:10.1186/1556-276X-7-468
PMCID: PMC3492109  PMID: 22908859
RF-MOMBE; InN; nanorods
2.  Complex distribution patterns of voltage-gated calcium channel α-subunits in the spiral ganglion 
Hearing research  2011;278(1-2):52-68.
As with other elements of the peripheral auditory system, spiral ganglion neurons display specializations that vary as a function of location along the tonotopic axis. Previous work has shown that voltage-gated K+ channels and synaptic proteins show graded changes in their density that confers rapid responsiveness to neurons in the high frequency, basal region of the cochlea and slower, more maintained responsiveness to neurons in the low frequency, apical region of the cochlea. In order to understand how voltage-gated calcium channels (VGCCs) may contribute to these diverse phenotypes, we identified the VGCC α-subunits expressed in the ganglion, investigated aspects of Ca2+-dependent neuronal firing patterns, and mapped the intracellular and intercellular distributions of seven VGCC α-subunits in the spiral ganglion in vitro.
Initial experiments with qRT-PCR showed that eight of the ten known VGCC α-subunits were expressed in the ganglion and electrophysiological analysis revealed firing patterns that were consistent with the presence of both LVA and HVA Ca2+ channels. Moreover, we were able to study seven of the α-subunits with immunocytochemistry, and we found that all were present in spiral ganglion neurons, and that three of them were neuron-specific (CaV1.3, CaV2.2, and CaV3.3). Further characterization of neuron-specific α-subunits showed that CaV1.3 and CaV3.3 were tonotopically-distributed, whereas CaV2.2 was uniformly distributed in apical and basal neurons. Multiple VGCC α-subunits were also immunolocalized to Schwann cells, having distinct intracellular localizations, and, significantly, appearing to distinguish putative compact0 (CaV2.3, CaV3.1) from loose (CaV1.2) myelin.
Electrophysiological evaluation of spiral ganglion neurons in the presence of TEA revealed Ca2+ plateau potentials with slopes that varied proportionately with the cochlear region from which neurons were isolated. Because afterhyperpolarizations were minimal or absent under these conditions, we hypothesize that differential density and/or kinetics of one or more of the VGCC α-subunits could account for observed tonotopic differences. These experiments have set the stage for defining the clear multiplicity of functional control in neurons and Schwann cells of the spiral ganglion.
doi:10.1016/j.heares.2011.01.016
PMCID: PMC3223918  PMID: 21281707
Spiral ganglion neurons; primary afferents; firing patterns; ion channels; calcium channels; VGCC; myelin; Schwann cells
3.  A simple, innovative way to reduce rhinitis symptoms after sedation during endoscopy 
BACKGROUND:
Supplemental oxygen is routinely given via nasal cannula (NC) to patients undergoing moderate sedation for endoscopy. Some patients complain of profuse rhinorrhea and/or sneezing after the procedure, which results in additional medical costs and patient dissatisfaction.
OBJECTIVES:
To determine the causal relationship between the route of oxygen delivery and troublesome nasal symptoms, and to seek possible solutions.
METHODS:
Patients (n=836) were randomly assigned to one of the three following groups: the NC group (n=294), the trimmed NC (TNC) group (n=268) and the nasal mask (NM) group (n=274). All received alfentanil 12.5 μg/kg and midazolam 0.06 mg/kg, and adjunct propofol for sedation. Supplemental oxygen at a flow rate of 4 L/min was used in the NC and TNC groups, and 6 L/min in the NM group. The incidence of nasal symptoms and hypoxia were assessed.
RESULTS:
The incidence of rhinitis symptoms was significantly higher in the NC group (7.1%) than in the TNC (0.4%) and NM (0%) groups (P<0.001). The incidence of hypoxia was lower in the NC group (3.1%) (P=0.040). All hypoxia events were transient (ie, less than 30 s in duration). On spirometry, the mean value of the lowest saturation of peripheral oxygen was found to be significantly lower in the NM group (96.8%) than in the NC group (97.7%) (P=0.004).
CONCLUSIONS:
Trimming the NC or using NMs reduced the incidence of rhinitis symptoms; however, the incidence of hypoxia was higher. Further investigation regarding the efficiency of oxygen supplementation is warranted in the design of novel oxygen delivery devices.
PMCID: PMC3043006  PMID: 21321676
Endoscopy; Nasal cannula; Rhinitis; Supplemental oxygenation
4.  Aqueous Extract of the Edible Gracilaria tenuistipitata Inhibits Hepatitis C Viral Replication via Cyclooxygenase-2 Suppression and Reduces Virus-Induced Inflammation 
PLoS ONE  2013;8(2):e57704.
Hepatitis C virus (HCV) is an important human pathogen leading to hepatocellular carcinoma. Using an in vitro cell-based HCV replicon and JFH-1 infection system, we demonstrated that an aqueous extract of the seaweed Gracilaria tenuistipitata (AEGT) concentration-dependently inhibited HCV replication at nontoxic concentrations. AEGT synergistically enhanced interferon-α (IFN-α) anti-HCV activity in a combination treatment. We found that AEGT also significantly suppressed virus-induced cyclooxygenase-2 (COX-2) expression at promoter transactivation and protein levels. Notably, addition of exogenous COX-2 expression in AEGT-treated HCV replicon cells gradually abolished AEGT anti-HCV activity, suggesting that COX-2 down-regulation was responsible for AEGT antiviral effects. Furthermore, we highlighted the inhibitory effect of AEGT in HCV-induced pro-inflammatory gene expression such as the expression of tumour necrosis factor-α, interleukin-1β, inducible nitrite oxide synthase and COX-2 in a concentration-dependent manner to evaluate the potential therapeutic supplement in the management of patients with chronic HCV infections.
doi:10.1371/journal.pone.0057704
PMCID: PMC3585194  PMID: 23469054
5.  Green Tea Phenolic Epicatechins Inhibit Hepatitis C Virus Replication via Cycloxygenase-2 and Attenuate Virus-Induced Inflammation 
PLoS ONE  2013;8(1):e54466.
Chronic hepatitis C virus (HCV) infection is the leading risk factor for hepatocellular carcinoma (HCC) and chronic liver disease worldwide. Green tea, in addition to being consumed as a healthy beverage, contains phenolic catechins that have been used as medicinal substances. In the present study, we illustrated that the epicatechin isomers (+)-epicatechin and (−)-epicatechin concentration-dependently inhibited HCV replication at nontoxic concentrations by using in vitro cell-based HCV replicon and JFH-1 infectious systems. In addition to significantly suppressing virus-induced cyclooxygenase-2 (COX-2) expression, our results revealed that the anti-HCV activity of the epicatechin isomers occurred through the down-regulation of COX-2. Furthermore, both the epicatechin isomers additively inhibited HCV replication in combination with either interferon-α or viral enzyme inhibitors [2′-C-methylcytidine (NM-107) or telaprevir]. They also had prominent anti-inflammatory effects by inhibiting the gene expression of tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and inducible nitrite oxide synthase as well as the COX-2 in viral protein-expressing hepatoma Huh-7 cells. Collectively, (+)-epicatechin and (−)-epicatechin may serve as therapeutic supplements for treating HCV-related diseases.
doi:10.1371/journal.pone.0054466
PMCID: PMC3554764  PMID: 23365670

Results 1-5 (5)