Comparison of rocuronium-induced neuromuscular blockade in second trimester pregnant women and non-pregnant women.

BACKGROUND: This study set out to compare the onset and duration of rocuronium-induced neuromuscular blockade in second trimester pregnant women and non-pregnant women receiving general anesthesia. METHODS: Forty-seven pregnant (Group P) and forty-seven non-pregnant (Group C) women were enrolled. Anesthesia was induced with propofol 2.0 mg/kg and rocuronium 0.6 mg/kg, and neuromuscular blockade was assessed with an accelerometric sensor using train-of-four stimulation (TOF-Watch® SX). Tracheal intubation was performed at maximum depression of the first twitch (T1) and anesthesia was maintained with sevoflurane 1.5-2.5% and 50% oxygen in air. We recorded the times to maximum T1 depression and 5% and 25% T1 recovery, as well as the mean arterial pressure and heart rate at baseline, injection of rocuronium, intubation, and 5% and 25% T1 recovery. RESULTS: The onset of rocuronium-induced neuromuscular blockade (time to maximum T1 depression) did not differ significantly between the groups. The duration (time to 25% T1 recovery) was significantly longer in Group P than in Group C (45.7 ±â€¯12.9 min vs 40.6 ±â€¯10.4 min, P <0.037). During the recovery period from the blockade, the mean arterial pressure was significantly lower in Group P than in Group C. CONCLUSION: Our data showed that the rocuronium-induced neuromuscular blockade did not significantly differ in onset but lasted significantly longer in second trimester pregnant women compared with non-pregnant women.

Colossal Terahertz Magnetoresistance at Room Temperature in Epitaxial La0.7Sr0.3MnO3 Nanocomposites and Single-Phase Thin Films.

Colossal magnetoresistance (CMR) is demonstrated at terahertz (THz) frequencies by using terahertz time-domain magnetospectroscopy to examine vertically aligned nanocomposites (VANs) and planar thin films of La0.7Sr0.3MnO3. At the Curie temperature (room temperature), the THz conductivity of the VAN was dramatically enhanced by over 2 orders of magnitude under the application of a magnetic field with a non-Drude THz conductivity that increased with frequency. The direct current (dc) CMR of the VAN is controlled by extrinsic magnetotransport mechanisms such as spin-polarized tunneling between nanograins. In contrast, we find that THz CMR is dominated by intrinsic, intragrain transport: the mean free path was smaller than the nanocolumn size, and the planar thin-film exhibited similar THz CMR to the VAN. Surprisingly, the observed colossal THz magnetoresistance suggests that the magnetoresistance can be large for alternating current motion on nanometer length scales, even when the magnetoresistance is negligible on the macroscopic length scales probed by dc transport. This suggests that colossal magnetoresistance at THz frequencies may find use in nanoelectronics and in THz optical components controlled by magnetic fields. The VAN can be scaled in thickness while retaining a high structural quality and offers a larger THz CMR at room temperature than the planar film.

Strain Localization in Thin Films of Bi(Fe,Mn)O3 Due to the Formation of Stepped Mn(4+)-Rich Antiphase Boundaries.

The atomic structure and chemistry of thin films of Bi(Fe,Mn)O3 (BFMO) films with a target composition of Bi2FeMnO6 on SrTiO3 are studied using scanning transmission electron microscopy imaging and electron energy loss spectroscopy. It is shown that Mn(4+)-rich antiphase boundaries are locally nucleated right at the film substrate and then form stepped structures that are approximately pyramidal in three dimensions. These have the effect of confining the material below the pyramids in a highly strained state with an out-of-plane lattice parameter close to 4.1 Å. Outside the area enclosed by the antiphase boundaries, the out-of-plane lattice parameter is much closer to bulk values for BFMO. This suggests that to improve the crystallographic perfection of the films whilst retaining the strain state through as much of the film as possible, ways need to be found to prevent nucleation of the antiphase boundaries. Since the antiphase boundaries seem to form from the interaction of Mn with the Ti in the substrate, one route to perform this would be to grow a thin buffer layer of pure BiFeO3 on the SrTiO3 substrate to minimise any Mn-Ti interactions.

Community periodontal treatment needs in South Korea.

OBJECTIVES: This study aimed to assess the relationship between socio-economic factors and community periodontal treatment needs in Korea. METHODS: Data were obtained from the year 2009 Korean National Health and Nutrition Examination Survey. Our analysis included 7510 survey participants over the age of 19 years. To assess the relationship between socio-economic factors and the need for periodontal scaling, we performed multivariate logistic regression analyses for data with a complex sampling structure. PASW statistics 19.0 (SPSS Inc., Chicago, IL, USA) was used to perform the statistical analyses, and the results were expressed as odds ratios (OR) with corresponding 95% confidence intervals (CIs). RESULTS: A very high percentage of Korean adults required periodontal scaling (71.5%). After adjusting for sex, age, and socio-economic factors, the need for periodontal scaling was associated with low levels of education (OR: 1.41, 95% CI: 1.03-1.93), low incomes (OR: 1.27, 95% CI: 1.01-1.60), employment as a service and sales worker (OR: 1.39, 95% CI: 1.10-1.77), and employment as a manual worker (OR: 1.31, 95% CI: 1.02-1.69). CONCLUSIONS: In South Korea, the need for periodontal scaling was associated with socio-economic factors, such as low levels of education, low incomes, employment as a service and sales worker and employment as a manual worker. Consequently, clinical and community dental hygienists should consider adults with these risk factors as belonging to high-priority subgroups to whom they should respond first.

Cold testing of quasi-optical mode converters using a generator for non-rotating high-order gyrotron modes.

In this paper, we test the performance of a quasi-optical, internal-gyrotron mode converter. When cold testing mode converters, a rotating higher-order mode is commonly used. However, this requires a nontrivial design and precise alignment. We thus propose a new technique for testing gyrotron mode converters by using a simple, non-rotating, higher-order mode generator. We demonstrate the feasibility of this technique for a W-band gyrotron quasi-optical mode converter by examining the excitation of a TE6,2 mode from a non-rotating mode generator. Our results demonstrate that this new cold-test scheme is an easy and efficient method for verifying the performance of quasi-optical mode converters.

Induced magnetization in La0.7Sr0.3MnO3/BiFeO3 superlattices.

Using polarized neutron reflectometry, we observe an induced magnetization of 75 ± 25 kA/m at 10 K in a La(0.7)Sr(0.3)MnO(3) (LSMO)/BiFeO(3) superlattice extending from the interface through several atomic layers of the BiFeO(3) (BFO). The induced magnetization in BFO is explained by density functional theory, where the size of band gap of BFO plays an important role. Considering a classical exchange field between the LSMO and BFO layers, we further show that magnetization is expected to extend throughout the BFO, which provides a theoretical explanation for the results of the neutron scattering experiment.

Sciadopitysin alleviates methylglyoxal-mediated glycation in osteoblastic MC3T3-E1 cells by enhancing glyoxalase system and mitochondrial biogenesis.

Methylglyoxal (MG) is a precursor of advanced glycation end products, which contribute to diabetic complications, including bone defects. In the present study, the effect of sciadopitysin on MG-induced cytotoxicity was investigated using osteoblastic MC3T3-E1 cells. Pretreatment of MC3T3-E1 cells with sciadopitysin prevented the MG-induced cell death and protein adducts formation. Sciadopitysin restored the MG-induced change in glyoxalase activity almost to the control level and increased glutathione levels. In addition, sciadopitysin decreased MG-induced formation of intracellular reactive oxygen species (ROS), mitochondrial superoxide, and cardiolipin peroxidation. These findings suggest that sciadopitysin provides a protective action against MG-induced glycation by increasing MG detoxification system and by reducing oxidative stress. Pretreatment with sciadopitysin prior to MG exposure reduced MG-induced mitochondrial dysfunction by preventing mitochondrial membrane potential (MMP) dissipation and adenosine triphosphate (ATP) loss. The nitric oxide (NO) level was decreased by MG treatment, but it was significantly increased by sciadopitysin, suggesting that sciadopitysin may induce NO-dependent mitochondrial biogenesis. Furthermore, sciadopitysin treatment increased the levels of sirtuin 1 (SIRT1), peroxisome proliferator-activated receptor gamma coactivator 1 alpha (PGC-1α), nuclear respiratory factor 1 (NRF-1), and mitochondrial transcription factor A (TFAM). These findings indicate that sciadopitysin might exert its therapeutic effects via upregulation of mitochondrial biogenesis. Therefore, sciadopitysin may prevent the development of diabetic osteopathy.

Methylglyoxal induces oxidative stress and mitochondrial dysfunction in osteoblastic MC3T3-E1 cells.

Methylglyoxal is a reactive dicarbonyl compound produced by glycolytic processing and identified as a precursor of advanced glycation end products. The elevated methylglyoxal levels in patients with diabetes are believed to contribute to diabetic complications, including bone defects. The objective of this study was to evaluate the effect of methylglyoxal on the function of osteoblastic MC3T3-E1 cells. The data indicated that methylglyoxal decreased osteoblast differentiation and induced osteoblast cytotoxicity. Pretreatment of MC3T3-E1 cells with aminoguanidine (a carbonyl scavenger), Trolox (an antioxidant), and cyclosporin A (a blocker of the mitochondrial permeability transition pore) prevented methylglyoxal-induced cytotoxicity in MC3T3-E1 cells. However, BAPTA/AM (an intracellular Ca(2+) chelator) and dantrolene (an inhibitor of endoplasmic reticulum Ca(2+) release) did not reverse the cytotoxic effect of methylglyoxal. Methylglyoxal increased the formation of intracellular reactive oxygen species, mitochondrial superoxide, and cardiolipin peroxidation in osteoblastic MC3T3-E1 cells. Methylglyoxal also decreased the mitochondrial membrane potential and intracellular ATP and nitric oxide levels, suggesting that carbonyl stress-induced loss of mitochondrial integrity contributes to the cytotoxicity of methylglyoxal. Furthermore, the results demonstrated that methylglyoxal induced protein adduct formation, inactivation of glyoxalase I, and activation of glyoxalase II. Aminoguanidine reversed all aforementioned effects of methylglyoxal. Taken together, these data support the notion that high methylglyoxal concentrations have detrimental effects on osteoblasts through a mechanism involving oxidative stress and mitochondrial dysfunction.

Smooth emergence in men undergoing nasal surgery: the effect site concentration of remifentanil for preventing cough after sevoflurane-balanced anaesthesia.

BACKGROUND: Suppression of cough during emergence after nasal surgery is practical to avoid bleeding from the surgical site. Previously recommended effect-site concentration of remifentanil for preventing cough during emergence is restricted to female patients undergoing thyroid surgery, so we evaluated effective effect-site concentration of remifentanil for preventing cough during emergence for men undergoing nasal surgery. METHODS: Twenty-four American Society of Anesthesiologists (ASA) physical status I or II, between the ages of 18 and 60 years old, non-smoker male patients undergoing nasal surgery were enrolled in this study. The effective effect-site concentration for 50% of patients (EC(50) ) and and that for 95% of patients (EC(95) ) of remifentanil for preventing cough were determined by Dixon's up-and-down method and by isotonic regression method with a bootstrapping approach. Haemodynamic variables were compared in patients with cough and without cough during emergence. RESULTS: The EC(50) of remifentanil for preventing cough during emergence by Dixon's method was 2.17 ng/ml [standard deviation (SD) 0.38]. The estimated EC(50) and EC(95) of remifentanil using isotonic regression model with a bootstrapping approach were 2.35 ng/ml [95% confidence interval (CI) 1.89-2.66] and 2.94 ng/ml (95% CI 2.83-2.97), respectively. Mean arterial pressure and heart rate were significantly higher in patients with cough during emergence. Three out of 13 patients that received more than 2.5 ng/ml of remifentanil experienced a brief episode of bradypnea. CONCLUSIONS: The EC(95) of remifentanil for preventing cough in men after nasal surgery is 2.94 ng/ml. Remifentanil target-controlled infusion with established effect-site concentration could suppress cough in men during emergence from sevoflurane anaesthesia after nasal surgery, though reversible respiratory depression might arise at high effect-site concentration of remifentanil.

Dose-dependent attenuation by fentanyl on cough during emergence from general anesthesia.

BACKGROUND: Although fentanyl suppresses tracheal tube-induced cough during anesthetic recovery, it has not been proven if its antitussive effect is dose dependent and complication free. The purpose of this study is to evaluate the relationship between fentanyl doses and cough suppression during emergence from sevoflurane anesthesia. METHODS: Sixty patients undergoing thyroidectomy were randomly allocated to one of four groups (F0, F1, F1.5, and F2) according to the fentanyl dose (0 mcg/kg, 1 mcg/kg, 1.5 mcg/kg, or 2 mcg/kg). Fentanyl was administered immediately after sevoflurane discontinuation. Coughing was assessed throughout the periextubation period. The relationship between fentanyl dose and incidence of cough was analyzed using Cochran-Armitage trend test. Incidence of more than 30% elevation of mean arterial pressure (MAP) and heart rate (HR), awakening time, extubation time, and respiratory rate after extubation were recorded and compared using Mantel-Haenszel chi-square test and one-way analysis of variance. RESULTS: Fentanyl suppressed emergence cough in a dose-related manner (P = 0.002), and the ED(50) and ED(90) were 1.1 mcg/kg and 2.1 mcg/kg, respectively. The higher dose of fentanyl further reduced the number of patient with MAP and HR elevation (P = 0.003 and 0.005, respectively). Awakening time (8.4 ± 1.9 min) in F2 was comparable with that in F1 and F1.5. Respiratory rate (9 ± 2 bpm) and extubation time (11.9 ± 1.8 min) in F2 were only different from those in F0 (13 ± 3 bpm and 10.4 ± 1.1 min, respectively). CONCLUSIONS: Fentanyl suppressed cough in a dose-related manner during recovery from general sevoflurane anesthesia, and 2 mcg/kg may be considered as a proper dose.

Comparison of the effect-site concentrations of remifentanil for Streamlined Liner of the Pharynx Airway (SLIPA) versus laryngeal mask airway SoftSealTM insertion during target-controlled infusion of propofol.

This study was designed to determine the optimal dose of remifentanil required for the successful insertion of Streamlined Liner of the Pharynx Airway (SLIPA) and to compare it to that required for laryngeal mask airway (LMA) insertion in patients receiving a propofol infusion at a standard effect-site concentration. Fifty-eight patients scheduled to undergo general anaesthesia were randomly assigned to either the SLIPA (n = 29) or LMA (n = 29) group. All patients were premedicated with midazolam 0.05 mg x kg(-1) and glycopyrrolate 0.004 mg x kg(-1) intramuscularly. After the administration of lignocaine 1 mg x kg(-1) intravenously, a propofol infusion was started at an effect-site concentration of 3.5 microg x ml(-1) with a remifentanil infusion without a neuromuscular blocking agent. The remifentanil dose was determined by the modified up-and-down method starting in each group at 4 ng x ml(-1). Six minutes after induction, the airway device was inserted. Airway device insertion was classified as 'success' or 'failure' based on patient response. From the isotonic regression analysis and bootstrap distribution, the EC50 of remifentanil for SLIPA and LMA were 0.93 ng x ml(-1) (95% confidence interval [CI] 0.81 to 1.50 ng x ml(-1) and 1.36 ng x ml(-1) (95% CI 1.19 to 2.06 ng x ml(-1)) respectively, and the EC95 for SLIPA and LMA insertions were 1.90 ng x ml(-1) (95% CI 1.39 to 1.95) and 2.43 ng x ml(-1) (95% CI 1.80 to 2.46 ng x ml(-1)) respectively. Using the 83% CIs from the bootstrap distribution, EC50 for SLIPA was significantly less than that of LMA (0.83 to 1.23 vs 1.26 to 2.00, respectively) (P < 0.05). These findings suggest that the insertion of SLIPA needs about a 32% lower depth of anaesthesia than LMA insertion.

Association of ABCB1 polymorphisms with the efficacy of ondansetron for postoperative nausea and vomiting.

We investigated whether the 2677G>T/A and 3435C>T polymorphisms of adenosine triphosphate-binding cassette subfamily B member 1 (ABCB1) affect the efficacy of ondansetron to prevent postoperative nausea and vomiting. One hundred and ninety-eight patients undergoing general anaesthesia were enrolled. Thirty minutes before the end of surgery, 0.1 mg.kg⁻¹ ondansetron was administered intravenously. The incidence of postoperative nausea and vomiting was compared between genotypes in the 2677G>T/A and 3435C>T polymorphisms of ABCB1. The incidence of postoperative nausea and vomiting was lower in patients with the 2677TT genotype (TT vs Non-TT = 25.9% vs 53.0%, p = 0.01) and 3435TT genotype (CC + CT vs TT = 52.6% vs 21.7%, p = 0.01) during the first 2 h after surgery. There were no significant differences in the incidence of postoperative nausea and vomiting between the different genotype groupings during period between 2 and 24 h after surgery. In conclusion, ABCB1 genotypes may be a clinical predictor of responsiveness for ondansetron.

Titrated propofol induction vs. continuous infusion in children undergoing magnetic resonance imaging.

BACKGROUND: Propofol is the popular intravenous (i.v.) anaesthetic for paediatric sedation because of its rapid onset and recovery. We compared the efficacy and safety of a single dose and conventional infusion of propofol for sedation in children who underwent magnetic resonance imaging (MRI). METHODS: This was a double-blind, randomized-controlled study. One hundred and sixty children were assigned to group I (single dose) or II (infusion). Sedation was induced with i.v. propofol 2 mg/kg, and supplemental doses of propofol 0.5 mg/kg were administered until adequate sedation was achieved. After the induction of sedation, we treated patients with a continuous infusion of normal saline at a rate of 0.3 ml/kg/h in group I and the same volume of propofol in group II. In case of inadequate sedation, additional propofol 0.5 mg/kg was administered and the infusion rate was increased by 0.05 ml/kg/h. Induction time, sedation time, recovery time, additional sedation and adverse events were recorded. RESULTS: Recovery time was significantly shorter in group I compared with group II [0 (0-3) vs. 1 (0-3), respectively, P<0.001]. Group I (single dose) had significantly more patients with recovery time 0 compared with group II (infusion) (65/80 vs. 36/80, respectively, P<0.001). Induction and sedation times were not significantly different between groups. There was no significant difference in the frequency of additional sedation and adverse events between groups. CONCLUSION: A single dose of propofol without a continuous infusion can provide appropriate sedation in children undergoing MRI for <30 min.

Observation of large arrays of plasma filaments in air breakdown by 1.5-MW 110-GHz gyrotron pulses.

We report the observation of two-dimensional plasma filamentary arrays with more than 100 elements generated during breakdown of air at atmospheric pressure by a focused Gaussian beam from a 1.5-MW, 110-GHz gyrotron operating in 3-micros pulses. Each element is a plasma filament elongated in the electric field direction and regularly spaced about one-quarter wavelength apart in the plane perpendicular to the electric field. The development of the array is explained as a result of diffraction of the beam around the filaments, leading to the sequential generation of high intensity spots, at which new filaments are created, about a quarter wavelength upstream from each existing filament. Electromagnetic wave simulations corroborate this explanation and show very good correlation to the observed pattern of filaments.

Pair-breaking and superconducting state recovery dynamics in MgB2.

We present studies of the photoexcited quasiparticle dynamics in MgB2 where, using femtosecond optical techniques, Cooper pair-breaking dynamics (PBD) have been temporally resolved for the first time. The PBD are strongly temperature and photoexcitation intensity dependent. Analysis of the PBD using the Rothwarf-Taylor equations suggests that the anomalous PBD arises from the fact that in MgB2 photoexcitation is initially followed by energy relaxation to high frequency phonons instead of, as commonly assumed, e-e thermalization. Furthermore, the bare quasiparticle recombination rate and the probability for pair breaking by phonons have been determined.

The use of chimeric A2K(b) tetramers to monitor HLA A2 immune responses in HLA A2 transgenic mice.

HLA A2 (A2) transgenic mice are currently being used to compare different vaccination protocols. However, the monitoring of A2 restricted CTL in A2 transgenic mice have been hampered by poor staining efficiency of mouse CTL by A2 tetramers. We demonstrate here that chimeric A2 tetramers containing mouse H-2K(b) (K(b)) alpha3 domain (A2K(b) tetramers) can be used as staining reagents to monitor A2 restricted CTL responses in A2 transgenic mice. The increased ability of A2K(b) tetramers to stain mouse A2 restricted CTL, as compared with A2 tetramers, correlated with their higher binding affinity for mouse A2 restricted CTL. The use of these novel staining reagents will allow efficient comparison of vaccination strategies and rapid identification of novel CTL epitopes in A2 transgenic mice.

High current-carrying capability in c-axis-oriented superconducting MgB2 thin films.

In high-quality c-axis-oriented MgB2 thin films, we observed high critical current densities ( J(c)) of approximately 16 MA/cm(2) at 15 K under self-fields comparable to those of cuprate high-temperature superconductors. The extrapolated value of J(c) at 5 K was estimated to be approximately 40 MA/cm(2). For a magnetic field of 5 T, a J(c) of approximately 0.1 MA/cm(2) was detected at 15 K, suggesting that this compound would be a very promising candidate for practical applications at high temperature and lower power consumption. The vortex-glass phase is considered to be a possible explanation for the observed high current-carrying capability.

MgB2 superconducting thin films with a transition temperature of 39 kelvin.

We fabricated high-quality c axis-oriented epitaxial MgB2 thin films using a pulsed laser deposition technique. The thin films grown on (1 i 0 2) Al2O3 substrates have a transition temperature of 39 kelvin. The critical current density in zero field is approximately 6 x 10(6) amperes per cubic centimeter at 5 kelvin and approximately 3 x 10(5) amperes per cubic centimeter at 35 kelvin, which suggests that this compound has potential for electronic device applications, such as microwave devices and superconducting quantum interference devices. For the films deposited on Al2O3, x-ray diffraction patterns indicate a highly c axis-oriented crystal structure perpendicular to the substrate surface.

Soybean ethanol extract increases the function of osteoblastic MC3T3-E1 cells.

To investigate the bioactivities of soybean, which act on bone metabolism, we studied the effect of a soybean ethanol extract on the activity of osteoblast MC3T3-E1 cells. Soy extract (0.01-0.1 g/l) dose-dependently increased survival (P<0.05) and DNA synthesis (P<0.05) of MC3T3-E1 cells. In addition, soy extract (0.05 g/l) increased alkaline phosphatase activity (P<0.05) and collagen synthesis (P<0.05) of MC3T3-E1 cells. Moreover, the anti-estrogen tamoxifen eliminated the stimulation of MC3T3-E1 cells on the proliferation, ALP activity and collagen synthesis by soy extract, indicating that the main action of the soy extract on osteoblastic MC3T3-E1 cells is similar to that of estrogen effects. Treatment with soy extract prevented apoptosis, as assessed by a one-step sandwich immunoassay and DNA gel electrophoresis studies. This effect may be associated with the activation of the estrogen receptor, since we observed soy extract-mediated survival against apoptosis was blocked by the estrogen receptor antagonist tamoxifen in cells, further supporting a receptor-mediated mechanism of cell survival. These results suggest that osteoblast function is promoted by soy extract and that the estrogen receptor is involved in the response, thereby playing an important role in bone remodeling. In conclusion, soy extract has a direct stimulatory effect on bone formation in cultured osteoblastic cell in vitro. Presumably, dietary soy products are useful in the prevention of osteoporosis.