Expression of Kv1.5 K+ channels in activated microglia in vivo

OBJECTIVES: This study evaluated postoperative weight gain in children who received albumin versus crystalloid prime for cardiopulmonary bypass (CPB). DESIGN: A retrospective case-controlled study. Children whose extracorporeal (EC) circuit prime contained albumin (group 1) were matched with those whose prime contained only crystalloid (group 2) on the basis of age, weight, and surgical repair. SETTING: A university-based medical center. PARTICIPANTS: Seventy-six children (newborn to 4 years of age) who underwent CPB for correction of a congenital heart anomaly from 1993 to 1995. Group 1 underwent surgery from October 1994 to September 1995, and group 2 from February 1993 to September 1994. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Group 1 had less weight gain on postoperative days (PODs) 1, 2 and 3 compared with group 2 (p = 0.04 on POD 1). Albumin (grams per milliliter) prime and prime volume in milliliters per kilogram were the best predictors of weight gain (p < 0.004), with prime volume being the more important. Children who weighed less than 7.5 kg received more prime volume and had greater weight gain than children who weighed 7.5 kg or greater on PODs 1, 2, and 3 (p < 0.02). CONCLUSION: Data suggest that adding albumin to the EC circuit prime and minimizing the prime volume will result in less postoperative weight gain. Further prospective study with a larger sample is warranted to determine whether albumin prime offers other clinical benefits.     

Continuous low-voltage dc electroporation on a microfluidic chip with polyelectrolytic salt bridges

A microfluidic electroporator operating under a continuous low dc voltage (7 to approximately 15 V) is reported. The proposed electroporation microchip exploits the ionic conductivity of polyelectrolytic gel electrodes to precisely control the electric field that is applied to cells without bubble generation in the microchannel. In this study, pDADMAC (poly diallyldimethylammonium chloride) was used to efficiently apply the electric potential difference to the cells in the microchannels. Impedance analysis showed that the pDADMAC plugs could work as ionic conductors with a conductivity of approximately 16 S m(-1). In accordance with the calculation using CFD-ACE, an input voltage of only 10 V could generate an electric field of 0.9 kV cm(-1) across the microchannel; this meets the requirements for electropermeation. The electropermeation of K562 human chronic leukemia cells was observed in the microchip from 7 V, and the efficiency increased up to 60% upon the application of an input voltage of 15 V with a viability of 80%. An amount of 10(5) cells could be transfected every minute under a constant potential difference. The transfection and expression of DNA plasmids were also successfully demonstrated in the suspension cell line.     

TENORM aerosols in the Florida phosphate industry--assessment of lung fluid solubility and annual effective dose to workers

Inhalation exposure to workers in the Florida phosphate industry due to TENORM aerosols has not been adequately addressed owing to lack of aerosol information. One of the more critical factors is the absorption rate of inhaled radionuclides into blood. In this study, this parameter was characterised using an in vitro dissolution test. The solubility data and other aerosol information were then used for individualised dose assessments at six different Florida phosphate facilities. The solubility data support the selections of ICRP Publication 66 Type M for uranium and lead isotopes and Type S for thorium isotopes. Total annual effective doses are 0.34 +/- 0.12 mSv at granulator areas, 0.30 +/- 0.10 mSv at storage areas and 0.23 +/- 0.02 mSv at shipping areas. These findings are considerably lower than originally postulated in previous studies where no site-specific information on particle size and lung fluid solubility had been available.     

The potential antioxidant capacity and angiotensin I-converting enzyme inhibitory activity of Monascus-fermented soybean extracts: evaluation of Monascus-fermented soybean extracts as multifunctional food additives

ABSTRACT:  The potential antioxidant capacity and angiotensin I-converting enzyme (ACE) inhibitory activity of Monascus -fermented soybean extracts (MFSE) were investigated. The average antioxidant capacities of 70% ethanol extracts from soybean after fermenting for 15 d at 30 °C were increased by a 5.2 to 7.4-fold (0.26 mM trolox equivalent/g dry weight, 91.7% 1,1-diphenyl-2-picrylhydrazyl [DPPH] radical scavenging effect at 3 mg/mL) when compared with those of the unfermented soybean extracts ( P < 0.01). The potentially significant antioxidant properties of MFSE are associated with its content of bioactive mevinolins ( r = 0.85) and isoflavone aglycones ( r = 0.98), which were derived from the soybean during Monascus -fermentation. It was also found that the water extract having a molecular mass 1 to 3 kDa showed the highest ACE inhibitory activity (65.3%), which was remarkably greater (6.5 times) than the control.     

A low-power multi-band CMOS RF receiver front-end for ubiquitous sensor network applications

This paper presents the design and experimental results of a low-power multi-band RF receiver including a multi-band low-noise amplifier (LNA) and a down-conversion mixer based on the IEEE 802.15.4 standard for sensor node applications. A multi-band LNA with two inputs is tuned to two resonant frequencies by controlling the voltage on a switched MOS. The implemented RF receiver front-end achieves a maximum voltage conversion gain of 38 and 30 dB, NF of 6.2 and 9.2 dB at the 868/915 MHz and the 2.45 GHz bands, respectively. The RF receiver front-end dissipates total 3.0 mA (including I/Q mixers) under supply voltage of 1.8 V at both operation bands.     

Aptamer biosensors for label-free colorimetric detection of human IgE based on polydiacetylene (PDA) supramolecules

In this study, we demonstrate an aptamer-based biosensor (apta-biosensor) using PDA liposomes for label-free detection of allergy diagnosis by hIgE detection. In order to detect the target hIgE, the surface of PDA liposome were functionalized with hIgE antibody and anti-hIgE aptamer as a receptor, and the target hIgE onto the receptors was detected by the change of fluorescence signal. The hIgE antibody-modified PDA liposome biosensor had a serious problem that the immune reaction between receptor and target could not powerfully affect the change of florescence signal on PDA liposome. In order to solve this problem, the anti-hIgE aptamer which was far smaller than whole antibody was introduced as the receptor for the PDA liposome system. An aptamer-based PDA liposome biosensor was able to measure a quantity of target protein with various concentrations and at this time the detection limit was 141 ng/mL of the hIgE concentration. These results enabled diagnosis of allergy disease by an aptamer-based PDA liposome biosensor because real allergic patients showed high concentration of hIgE in serum (greater than 290 ng/mL). Therefore, we suggest that aptamer-modified PDA supramolecules as promising candidates for development of label-free colorimetric biosensors.     

Microfabrication and characterization of spray-coated single-wall carbon nanotube film strain gauges

We present the design, fabrication, and characterization results of single-wall carbon nanotube (SWCNT) film strain gauges for potential applications as highly sensitive strain, weight, or pressure sensors on the macro-scale. A batch microfabrication process was developed for practical device construction and packaging using spray-coated SWCNTs and a conventional semiconductor process. The prototype was characterized using a commercial metal foil gauge with tensile and compressive testing on a binocular load cell. Our test results demonstrated that the proposed SWCNT film gauges have a linear relationship between resistance changes and externally applied strain. The gauge factor ranged from 7.0 to 16.4 for four different micro-grid configurations, indicating that the maximum strain sensitivity of the prototype was approximately eight times greater than that of commercial gauges.     

Mode II fracture mechanisms of PBT-modified brittle epoxies

Mode II fracture behavior of poly(butylene terephthalate) (PBT)-modified epoxy systems are studied. Two different types of testing for mode II fracture are conducted. One was to investigate the fracture behavior of bulk epoxy systems, in comparison with mode I fracture, using single-edge notched specimens under skew symmetric four-point loading. The other was to investigate the fracture behavior of epoxy layers sandwiched between aluminium adherends using compact shear specimens. The mode II fracture toughness obtained from the former for modified systems has been found to increase significantly over the control, although the increase of mode I fracture toughness for modified systems over the control is moderate. This finding is discussed in relation with cavitation and equivalent mode I stress intensity factor and also in comparison with rubber-modified epoxy systems in the literature to account for the increase. In addition, the difference in fracture morphology between mode I and II is discussed. Mode II fracture toughness obtained from the latter for modified systems has also been found to increase significantly over the control. Morphology of fracture surfaces relating to this finding is discussed. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 69: 405–415, 1998     

Predictors of glass transition in the biodegradable poly‐lactide and poly‐lactide‐co‐glycolide polymers

The biodegradable polylactide (PLA) and polylactide‐co‐glycolides (PLGAs) are being widely investigated for use as scaffolds in bone and ligament reconstruction. The glass transition temperatures (T_g) for these polymers are generally greater than 37°C, causing PLA and PLGA devices to possess brittle characteristics in physiological conditions. To evaluate the possibility of obtaining PLGA polymers with T_g values below 37°C, we evaluated the determinants of T_g in PLA and PLGA copolymers. The T_g, changes in specific heat capacity (ΔC_p), and enthalpic relaxation (ΔH_g) in two consecutive heating cycles were correlated with lactide/glycolide content and intrinsic viscosity [η] for PLA, PLGAs 90:10, 75:25, 65:35, and 50:50. A linear correlation was observed between T_g and intrinsic viscosity, with 0.1 dL/g increase in viscosity resulting in an increase in T_g by about 3.55°C. The selection of PLA and PLGA copolymers with [η] values <0.19 dL/g, corresponding to a viscosity average molecular weight of <70 kDa, will obtain PLA/PLGA polymers with T_g values below 37°C. The lowest attainable T_g values were found to be 28–30°C. Intrinsic viscosity also correlated with ΔC_p differences between aged and rapidly cooled polymers, and is therefore important in predicting free volume changes within these polymers upon aging. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 1983–1987, 2006