Outcome of extensive descending aorta repair adopting present concepts of spinal cord preservatio

AIM: Preoperative radiological identification of the Adamkiewicz artery and intraoperative neurologic monitoring are known to be helpful for preventing paraplegia after thoracoabdominal aorta replacement. To answer whether they should be used routinely, we investigated the incidence of spinal cord ischemia after extensive descending aortic repair without using such modalities. METHODS: We retrospectively reviewed the outcome of 95 patients who underwent extensive descending thoracic (DTA) or thoracoabdominal aorta (TAA) repair without the Adamkiewicz artery identification or neurologic monitoring from 2006 through 2010. Spinal cord protection strategy consisted of distal aortic perfusion, cerebrospinal fluid drainage, mild hypothermia, and maintenance of hypertension (systolic≥120mmHg) through the second postoperative day. A few segmental arteries were empirically selected for reimplantation based on the size and the amount of backbleeding; overall 1.4 per patient, 0.3 for DTA, 1.4 for type I, 2.4 for type II, 0.9 for type III, and 0 for type IV TAA. RESULTS: Two patients died early after surgery. All the remaining patients awoke without paraplegia or paraparesis. Delayed deficit occurred in 7 patients (7.4%) after hypotensive events caused by sedation, bleeding, respiratory distress, or cardiac dysfunction. Three patients (3.2%) became permanently paraplegic and the other four recovered completely within 48 hours after cerebrospinal fluid drainage and elevation of systemic blood pressure. CONCLUSION: Even without the Adamkiewicz artery identification and neuromonitoring, the incidence of immediate paraplegia could be kept low by applying the strategy based on the modern concept of cord perfusion. The relatively high incidence of delayed deficit suggests the importance of postoperative hemodynamic management and prevention of cardiopulmonary complications.

Effect of lysine to digestible energy ratio on growth performance and carcass characteristics in finishing pigs

This experiment was performed to investigate the effects of lysine (Lys) to DE ratio on growth performance, and carcass characterics in finishing barrows. Ninety six cross-bred finishing barrows ((Landrace×Yorkshire) ×Duroc, average BW 58.25±0.48 kg) were assigned as a randomized complete block design by 2 energy levels and 4 Lys:DE ratios on the basis of BW to one of 8 treatments with 3 replications with 4 animals per pen. The levels of DE and Lys:DE ratio for each treatment were i) DE 3.35 Mcal/kg, 1.5 g Lys/Mcal DE, ii) DE 3.35 Mcal/kg, 1.8 g Lys/Mcal DE, iii) DE 3.35 Mcal/kg, 2.1 g Lys/Mcal DE, iv) DE 3.35 Mcal/kg, 2.4 g Lys/Mcal DE, v) DE 3.60 Mcal/kg, 1.5 g Lys/Mcal DE, vi) DE 3.60 Mcal/kg, 1.8 g Lys/Mcal DE, vii) DE 3.60 Mcal/kg, 2.1 g Lys/Mcal DE, viii) DE 3.60 Mcal/kg, 2.4 g Lys/Mcal DE. During finishing period from 58 kg to 103 kg of BW, increased energy density in the diet increased (p<0.05) ADG and gain:feed ratio, but did not influence ADFI. As Lys:DE ratio was increased, ADG, ADFI and gain:feed ratio were improved in finishing barrows (p<0.05). There were positive interactions (p<0.05) between carcass weight, grade, and backfat thickness and energy density and Lys level (p<0.05). In conclusion, data from our current study suggest that maximum yields including ADG, gain:feed ratio, carcass weight and grade can be achieved by administrating finishing pigs with an ideal Lys:DE ratio, Lys 2.1 g/DE Mcal.

Recanalization with Wingspan stent for acute middle cerebral artery occlusion in failure or contraindication to intravenous thrombolysis: a feasibility study

BACKGROUND AND PURPOSE

Recanalization with the Wingspan stent, which can be deployed rapidly and safely, is an option for treating acute ischemic stroke when intravenous thrombolysis has failed or is contraindicated. This study was performed to evaluate feasibility, efficacy, and safety of recanalization for acute middle cerebral artery occlusion using the Wingspan stent.

MATERIALS AND METHODS

We collected 10 patients with acute MCA occlusion in whom recanalization was not achieved with a standard intravenous thrombolysis, or who were ineligible for intravenous thrombolysis, or who presented after 3 hours of symptom onset and in whom the stent placement could be completed within 8 hours from symptom onset. We analyzed angiographic and clinical results.

RESULTS

Successful recanalization with the Wingspan stent was achieved in all patients. The mean NIHSS score on admission was 12.7 points (range 4-21). The occlusion sites were located in the 1st segment (n = 7; 2 left, 5 right) and 2nd segment (n = 3, all right) of the MCA. The mean time interval from stroke symptom onset to stent placement was 344.8 ± 76.3 minutes. No intracranial hemorrhage, vessel perforations, or dissections occurred in any patient. Nine patients improved on the NIHSS at 7 days. One patient did not have a change in the NIHSS score, even though the occluded artery was completely recanalized. At 7 days, the NIHSS score of all patients was 4.4 ± 4.7 (median 4, range 0-13). At discharge, an mRS of ≤ 3 was achieved in all patients and an mRS of ≤ 2 was achieved in 7 patients (70%).

CONCLUSIONS

This small case series demonstrates the feasibility of using the Wingspan stent safely and effectively for MCA occlusions when standard treatments are ineffective or not available.

YKL-40 in induced sputum after allergen bronchial provocation in atopic asthma

BACKGROUND

Serum chitinase-like proteins such as YKL-40 in asthmatic patients are known to positively correlate with disease severity but controversy remains regarding their role. The allergen bronchial provocation test (ABPT) can induce allergic airway inflammation in individuals with atopic asthma.

OBJECTIVE

To evaluate the induction and kinetics of YKL-40 during allergen-induced airway inflammation in atopic asthmatics.

METHODS

Thirteen patients were enrolled from May to November 2008. They all underwent ABPT with Dermatophagoides farinae crude extract. Induced sputums (IS) and serum were collected 3 times: 7 days before ABPT (baseline), 7 hours after ABPT, and 24 hours after ABPT. We examined the cytology of induced sputum (IS) and measured levels of YKL-40, interleukin (IL) 4, IL-5, IL-13, IL-33, tumor necrosis factor (TNF) alpha, and eosinophilic cationic protein (ECP) in IS and/or serum.

RESULTS

Following ABPT, total inflammatory cells, eosinophils, and neutrophils increased in a time-dependent manner in IS. YKL-40 levels were increased in IS but not in serum at 7 or 24 hours after ABPT (P=.011 and P=.006, respectively). Similarly to YKL-40, IL-5 and ECP levels were also increased in IS at 7 and 24 hours after ABPT (P=.011 for IL-5 and P=.006 for ECP). Overall, YKL-40 levels were well correlated with ECP levels in IS (p=0.576, P<.001).

CONCLUSIONS

YKL-40 levels increased immediately in IS but not in the serum of atopic asthmatics. The correlation between YKL-40 levels and ECP in IS suggests that YKL-40 may play a pathophysiologic role in human atopic asthma.

P1-01-07: ErbB-2 Peptide Vaccination Suppresses Spontaneous Tumorigenesis and Tumor Stem Cell Expansion in MMTV-PyVT Transgenic Mouse

Immunization targeting ErbB-2 could have considerable therapeutic potential by controlling growth and metastasis of highly aggressive tumor cells in the earlier preclinical and clinical studies. Just a few studies have examined preventive potential of ErbB-2 vaccines in preclinical studies. However, animal model systems used in the previous studies were tumor transplantation or neu-transgenic mouse, which were not relevant to human HER-2 positive breast tumorigenesis. In this study, active immunotherapy against tumor antigen ErbB-2/neu for primary prevention of breast cancer was tested using FVB/N-Tg (MMTV-PyVT) transgenic mice model. Mice were grouped to receive either ErbB-2 peptide vaccine, immune adjuvant only, tetanus toxoid, or PBS every 2 weeks for 3 times and monthly thereafter. The MMTV-PyVT transgenic mice in control groups (PBS, immune adjuvant only, or tetanus toxoid peptide) developed spontaneous mammary adenocarcinomas in 12 to 15 weeks, but vaccination against ErbB-2 strongly suppressed tumor formation by 30 weeks of observation. Further pathologic examination showed complete prevention of tumorigenesis was observed in ErbB-2 vaccinated mice, whereas the mice in control groups developed highly aggressive ErbB-2 overexpressing tumors similar to human breast cancer. The tumor protective effect of peptide vaccination was associated with induction of ErbB-2-specific humoral immune responses as well as T cell responses. Additionally, role of signal through ErbB-2 pathway and the relationship with stemness of cancer cells were determined by Aldefluor assay, mammosphere formation assay using Mouse mammary carcinoma (MMC) cells in vitro, and level of nestin expression determined by Western blot analysis. Further analysis of mammosphere formation capacity of MMC cells using immune sera showed that sera from ErbB2 vaccinated mice had a significant inhibitory effect on mammosphere formation in ErbB-2 overexpressing MMC cells. These results suggest that ErbB-2 targeting by cancer vaccination might be useful adjuvant to standard therapy, helping to prevent relapse in patients with ErbB-2-overexpressing tumors by suppressing stem/progenitor cell population.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P1-01-07.

A co-twin study of the relative effect of birth weight and gestational age on retinopathy of prematurity

PURPOSE

To determine the relative effect of birth weight and gestational age on retinopathy of prematurity (ROP) using preterm twin pairs discordant for birth weight.

METHODS

This study was a retrospective cohort study including 55 consecutive twin pairs of 110 preterm infants (gestational age ≤33 weeks). The outcomes of ROP including occurrence (any stage), severe ROP (stage 3 or more), and clinically significant ROP requiring laser treatment were compared between twins with the lower birth weight from each pair and their co-twins with the higher birth weight. Using twin pairs having different birth weight and identical gestational age, the independent effects of prematurity and intrauterine growth on ROP could be evaluated. Other perinatal morbidities related to prematurity were also compared between twin pairs.

RESULTS

No significant differences in ROP between larger and smaller infants were observed in the twin-paired analysis while analysis on individual infants showed strong association between small birth weight and ROP outcomes. However, in both the larger and smaller infant groups, gestational age of <28 weeks was significantly associated with ROP outcomes. No differences were found between twin pairs regarding other perinatal morbidities including bronchopulmonary dysplasia, respiratory distress syndrome, patent ductus arteriosus, intraventricular hemorrhage, and periventricular leukomalacia.

CONCLUSIONS

Birth weight is not associated with ROP, while gestational age is in the twin-paired study, suggesting that gestational age is a better predictor of ROP than birth weight. This indicates that maturity is more important in the pathogenesis of ROP than intrauterine growth.

Predictive value of intra-amniotic and serum markers for inflammatory lesions of preterm placenta

OBJECTIVE

To compare the relative predictive values of amniotic fluid (AF) matrix metalloproteinase-9 (MMP-9), interleukin-6 (IL-6), and serum C-reactive protein (CRP) for histologic chorioamnionitis and intra-amniotic infection in women with preterm labor or preterm premature rupture of membranes (PROM).

STUDY DESIGN

This retrospective cohort study included 99 consecutive women with preterm labor or preterm PROM (21-35 weeks' gestation) who delivered within 72 h of transabdominal amniocentesis. The AF was cultured for aerobic and anaerobic bacteria and for genital mycoplasmas and was assayed for MMP-9 and IL-6 levels. Maternal serum CRP was measured immediately after amniocentesis. The placentas were examined histologically.

MAIN OUTCOME MEASURES

histologic chorioamnionitis and intra-amniotic infection.

RESULTS

The prevalence of histologic chorioamnionitis and a positive AF culture was 44% (44/99) and 28% (28/99), respectively. In predicting intra-amniotic infection, AF MMP-9 had a significantly higher area under the curve (AUC: 0.94 [95% CI, 0.87-0.98]) than AF IL-6 (0.87 [95% CI, 0.78-0.84]; P < 0.05) and serum CRP (0.76 [95% CI, 0.66-0.84]; P < 0.001) and a higher sensitivity and specificity than serum CRP (P < 0.01, respectively). However, in predicting histologic chorioamnionitis, there were no significant differences in AUCs among the three tests (AF MMP-9: 0.78 [95% CI, 0.68-0.85]; AF IL-6: 0.76 [95% CI, 0.66-0.84]; serum CRP: 0.76 [95% CI, 0.66-0.84]). In a sub-analysis of 71 women without intra-amniotic infection, histologic chorioamnionitis was associated with an elevated serum CRP level (P < 0.05), but not with the level of AF IL-6 or MMP-9 (P = 0.232 and P = 0.402, respectively).

CONCLUSIONS

The AF MMP-9 has a better overall diagnostic performance than the AF IL-6 and maternal serum CRP in predicting intra-amniotic infection. However, the serum CRP level obtained up to 72 h before delivery appears to be an important marker for early identification of histologic chorioamnionitis in women without intra-amniotic infection.

Comparison between sonographic cervical length and Bishop score in preinduction cervical assessment: a randomized trial

OBJECTIVE

To compare sonographically measured cervical length with the Bishop score in determining the requirement for prostaglandin administration for preinduction cervical ripening in nulliparae at term.

METHODS

One hundred and fifty-four women with singleton pregnancies at term who were scheduled for induction of labor were randomly assigned to receive prostaglandin for preinduction cervical ripening based on the Bishop score or sonographic cervical length. A cervix unfavorable for treatment with prostaglandin for preinduction cervical ripening was defined as having either a Bishop score of ≤ 4 or a cervical length of ≥ 28 mm. The primary outcome measures were induction success (defined as an ability to achieve the active phase of labor) and the percentage of patients treated with prostaglandin for preinduction cervical ripening.

RESULTS

The two groups were similar with respect to maternal demographics, gestational age, cervical length, and Bishop score. The rates of induction success and Cesarean delivery, the interval to active phase of labor, and the interval to delivery were also similar in the two groups. However, in the transvaginal ultrasound group (n = 77), prostaglandin was administered to only 36% of the nulliparae compared with 75% of those in the Bishop score group (n = 77) (P < 0.0001).

CONCLUSION

In comparison with the Bishop score, the use of sonographic cervical length for assessing the cervix prior to induction of labor can reduce the need for prostaglandin administration by approximately 50% without adversely affecting the outcome of induction in nulliparae at term if the cut-off values used are a Bishop score of ≤ 4 and a cervical length of ≥ 28 mm.

Sustainable landfilling in tropical conditions: comparison between open and closed cell approach

Two landfill test cells were constructed in a tropical climate using locally available low-cost materials. One cell was operated without a cover on the municipal solid waste to simulate 'open landfill' conditions and the other cell was covered to create 'closed landfill' conditions. Both test cells were monitored over a period of 290 days under rainy, dry and artificial wetting conditions. Due to the relatively high compaction density of waste in the closed test cell, the substrate settlement was gradual and comparatively lower than in the open test cell. Multiple top covers in the closed test cell resulted in significant run-off of incident precipitation during the rainy season, which delayed the waste stabilization and subsequently produced a lesser volume of leachate. On the other hand, operation of the open test cell was found to be advantageous in terms of leachate management and substrate settlement along with waste stabilization pattern. Infiltration of rain-water into the waste mass leached out the maximum organic pollutants and oxidized the nitrogen content, which is deemed to be a benefit of operating an open cell landfill under tropical conditions. Artificial wetting during dry periods by recirculation of stored leachate notably accelerated the waste stabilization and secondary substrate settlement in the open test cell. The continuous monitoring of ground-water quality from the site showed only seasonal variations.

Comparison of saline wastewater treatment performance of SBR with repeated starvation under aerobic and non-aerobic conditions

This study investigated the effects of repeated starvation and feeding on the performance of a sequencing batch reactor (SBR) used for treating saline wastewater. The effects of aerobic and non-aerobic conditions on the sludge during starvation were evaluated to recover the performance of the SBR in terms of floc size and pollutant removal after resuming wastewater feeding. The floc size, fractal dimension, sludge volume index (SVI), specific oxygen uptake rate (SOUR), and pollutant removal efficiency were monitored. Experiment results revealed that the floc size and fractal dimensions decreased during starvation under both aerobic and non-aerobic conditions and increased after re-feeding wastewater. However, the difference in floc physical characteristics and performance depended on the starvation condition and was pronounced as starvation and re-feeding were repeated. The floc size and fractal dimensions decreased from 152.7 to 72.2 and 1.98 to 1.79 at the end of the fourth starvation period, resulting in deterioration of the sludge settleability and effluent quality. On the other hand, the floc size and fractal dimensions decreased from 158.7 to 135.7 and 1.95 to 1.81 at the end of the fourth starvation period but remained relatively constant after sludge adaptation. Some correlations were observed between the parameters monitored in this study. The results showed that maintaining the sludge under non-aerobic conditions was an effective strategy for reducing the effects of repeated starvation.

Non-invasive prediction of intra-amniotic inflammation in women with preterm labor

OBJECTIVE

To develop a model based on non-invasive variables to predict the probability of intra-amniotic inflammation in women with preterm labor and intact membranes.

METHODS

Transvaginal ultrasonography and digital examination for the assessment of cervical length and cervical dilatation were performed, and maternal blood was collected for the determination of C-reactive protein and white blood cell (WBC) count immediately after amniocentesis in 153 consecutive women with preterm labor. Amniotic fluid obtained by amniocentesis was cultured for aerobic and anaerobic bacteria and mycoplasmas, and the WBC was determined. Intra-amniotic inflammation was defined as an elevated amniotic fluid interleukin-6 concentration (> 2.6 ng/mL). Receiver-operating characteristics (ROC) curves and logistic regression analysis were used for statistical analysis.

RESULTS

The prevalence of a positive amniotic fluid culture was 7.2% (11/153) and the prevalence of intra-amniotic inflammation was 19.6% (30/153). The final logistic regression model was based on non-invasive clinical variables, including gestational age at assessment, cervical length and maternal blood WBC count, which were the best predictors of intra-amniotic inflammation. The model was shown to have an adequate goodness of fit (P = 0.754), and the area under the ROC curve was 0.724, indicating reasonably good discrimination.

CONCLUSION

In women with preterm labor and intact membranes, the risk for intra-amniotic inflammation can be predicted non-invasively with a risk score based on gestational age, cervical length and maternal blood WBC count.

Degree of cervical shortening after initial induction of labor as a predictor of subsequent successful induction

OBJECTIVE

To evaluate whether the degree of cervical length shortening is valuable in predicting the success of serial induction of labor on the second day in women in whom it failed on the first day, and to compare its performance with that of cervical length.

METHODS

This was a prospective observational study. We enrolled 92 consecutive women with singleton gestations at > 34.0 weeks' gestation who failed labor induction on the first day of serial induction. Transvaginal sonographic measurement of cervical length and determination of the Bishop score were undertaken before performing each labor induction on the first and second days.

RESULTS

The overall success rate of labor induction performed on the second day was 65% (60/92). Multiple logistic regression analysis demonstrated that the degree of cervical length shortening and cervical length were significantly associated with the successful induction of labor after adjustment for body mass index, parity, use of prostaglandin and Bishop score. There were no significant differences between areas under the ROC curves for degree of cervical length shortening and cervical length.

CONCLUSIONS

The degree of cervical length shortening is valuable in predicting the success of induction of labor on the second day in women in whom induction failed on the first day. However, compared with sonographic cervical length it is no better at predicting the success of subsequent induction of labor.

Clinical and sonographic parameters at 37 weeks' gestation for predicting the risk of primary Cesarean delivery in nulliparous women

OBJECTIVES

To identify the clinical and sonographic parameters at 37 weeks' gestation that predict the risk of Cesarean delivery in labor for nulliparas.

METHODS

This prospective observational study recruited nulliparas with singleton pregnancies at 37 weeks' gestation. Determination of the Bishop score, ultrasound measurement of the cervical length, and fetal biometry were performed. The clinical parameters studied were maternal age, height and weight and Bishop score. The sonographic parameters included fetal biparietal diameter, femur length, abdominal circumference (AC), estimated fetal weight (EFW), amniotic fluid index and cervical length.

RESULTS

Four hundred and fifty-three women were examined; 57 women (12.6%) underwent an emergency Cesarean delivery in labor. Logistic regression analysis identified maternal age and height and fetal AC and EFW, but not cervical length or Bishop score, as the best predictors of Cesarean delivery. Of these predictors, maternal age and height and fetal AC at 37 weeks were included in a final model for risk scoring. The model was shown to have an adequate goodness of fit (P = 0.473), and the area under the receiver-operating characteristics curve was 0.758, indicating reasonably good discrimination.

CONCLUSIONS

Maternal age and height and fetal AC and EFW at 37 weeks' gestation are the most important parameters in predicting the risk of Cesarean delivery in nulliparas; sonographic measurement of the cervical length and the Bishop score were not predictive of Cesarean delivery. A predictive model using these parameters at 37 weeks provides useful information in the decision-making process regarding the mode of delivery.

Optimum condition of anisotropic plasma etching for improving bending properties of ionic polymer-metal composites

We presented an anisotropic plasma etching technique by reactive ion etcher (RIE) as a new pretreatment method of fabrication of ionic polymer-metal composite (IPMC). We already found that the new technique provided large displacement to the fabricated IPMC in the presence of low applied voltage. However, we did not examine the optimum condition for the anisotropic plasma etching. In this research, we tried to figure out optimum treatment condition of film in etcher. Nafion (by DuPont) films were etched using various etching time and shadow masks with various slit and space sizes. The etched samples were plated with Pt at top and bottom side by Oguro's reduction method. The surface morphology of fabricated IPMCs was characterized by SEM. And, we've measured surface resistance, bending displacement, and driving force in order to check the IPMC properties out. Here, we found that optimum condition for pre-treatment of Nafion was 1 min for etching time under shadow mask with 200 microm slit and 100 microm space.

High sensitive NO2 gas sensor with low power consumption using selectively grown ZnO nanorods

The noble gas sensor using multiple ZnO nanorods was fabricated with CMOS compatible process and sol-gel growth method on selective area and gas response characteristics to NO2 gas of the sensor device were investigated. We confirmed the sensors had high sensitive response denoted by the sensitivity of several tens for NO2 gas sensing and also showed pretty low power consumption close to 20 mW even though the recovery of resistance come up to almost the initial value.

Low power consumption and high sensitivity carbon monoxide gas sensor using indium oxide nanowire

In this paper, micro gas sensor was fabricated using indium oxide nanowire for effective gas detection and monitoring system. Indium oxide nanowire was grown using thermal CVD, and their structural properties were examined by the SEM, XRD and TEM. The electric properties for microdropped indium oxide nanowire device were measured, and gas response characteristics were examined for CO gas. Sensors showed high sensitivity and stability for CO gas. And with below 20 mw power consumption, 5 ppm CO could be detected.

Electron beam induced current measurements on single-walled carbon nanotube devices

We report on electron beam induced current (EBIC) from individual carbon nanotubes (CNTs) which are in contact with metal electrodes. The EBIC signals originate from the diffusion of excess carriers induced by the electron beam bombardment. The EBIC image enables us to locate the individual CNTs efficiently. From the polarity of the EBIC signals we can identify the electrical contacts to the metal electrodes. More importantly, we demonstrate that the EBIC can be used to characterize the local electrical properties of CNT-based devices, such as asymmetry in metal contacts and the presence of defects. EBIC is also observed regardless of the presence of insulating surfaces, indicating that the EBIC is a result of the direct interaction between the CNTs and the electron beams.

Inhibitory effects on mushroom tyrosinase by flavones from the stem barks of Morus lhou (S.) Koidz

Five flavones displaying tyrosinase inhibitory activity were isolated from the stem barks of Morus lhou (S.) Koidz., a cultivated edible plant. The isolated compounds were identified as mormin (1), cyclomorusin (2), morusin (3), kuwanon C (4), and norartocarpetin (5). Mormin (1) was characterized as a new flavone possesing a 3-hydroxymethyl-2-butenyl at C-3. The inhibitory potencies of these flavonoids toward monophenolase activity of mushroom tyrosinase were investigated. The IC50 values of compounds 1-5 for monophenolase activity were determined to be 0.088, 0.092, 0.250, 0.135 mM, and 1.2 microM, respectively. Mormin (1), cyclomorusin (2), kuwanon C (4) and norartocarpetin (5) exhibited competitive inhibition characteristics. Interestingly norartocarpetin (5) showed a time-dependent inhibition against oxidation of L-tyrosine: it also operated under the enzyme isomerization model (k5 = 0.8424 min(-1), k6 = 0.0576 min(-1), K(app)(i) = 1.354 microM).

Electroactive polymer actuator with high response speed through anisotropic surface roughening by plasma etching

Plasma etching was performed to improve displacement and response speed of IPMC actuator through homogeneous roughening and anisotropic surface treatment. We found that the anisotropic surface treatment by plasma etching of Nafion in the pre-treatment process gave the response speed and displacement of resulting IPMC which was 2 times faster and 1.5 times larger than those manufactured by the sandblasting, respectively.

Electrical characterization of ZnO single nanowire device for chemical sensor application

Vertically well-aligned high quality ZnO nanowires were grown on GaN epilayer on c-plane sapphire via a vapor-liquid-solid (VLS) process by introducing an Au thin film (3 nm) as a catalyst. ZnO single nanowire device was ingenuously fabricated by combining conventional optical lithography and high resolution electron beam lithography and its current-voltage characteristics were measured with doing the post process to acquire reproducible performance as a chemical gas sensor. And its temperature dependent current-voltage characteristics were measured to investigate temperature dependant electrical transport. The ZnO nanowire device showed slightly non-ohmic current-voltage characteristics which may be due to back-to-back configuration of the diodes with the insulating contact barriers and showed an relatively small activation energy of 0.2 eV. To test our device as a chemical sensor, the NO2 gas response was reported at the elevated temperature.

Kurarinol, tyrosinase inhibitor isolated from the root of Sophora flavescens

It is well known that flavanones, sophoraflavanone G 1, kurarinone 2, and kurarinol 3, from the root of Sophora flavescens, have extremely strong tyrosinase inhibitory activity. This study delineates the principal pharmacological features of kurarinol 3 that lead to inhibition of the oxidation of l-tyrosine to melanin by mushroom tyrosinase (IC(50) of 100 nM). The inhibition kinetics analyses unveil that compounds 1 and 2 are noncompetitive inhibitors. However similar analysis shows kurarinol 3 to be a competitive inhibitor. Compounds 1 and 2 exhibited potent antibacterial activity with 10 microg/disk against Gram-positive bacteria, whereas kurarinol 3 did not ostend any antibacterial activity. Interestingly, kurarinol 3 inhibits production of melanin in S. bikiniensis without affecting the growth of microorganism. It is thus distinctly different from the other tyrosinase inhibitors 1 and 2. In addition, kurarinol 3 manifests relatively low cytotoxic activity (EC(50)>30 microM) compared to 1 and 2. To account for these observations, we conducted molecular modeling studies. These suggested that the lavandulyl group within 3 is instrumental in the interaction with the enzyme. More specifically, the terminal hydroxy function within the lavandulyl group is most important for optimal binding.