Search

A number of clinical studies have suggested that radiant heat improves the healing of selected acute and chronic wounds. The purpose of this study was to investigate in vitro the effect of intermittent radiant heating on the growth of human skin fibroblasts using a radiant heat-producing dressing with a designated temperature of 38 °C. In initial experiments cells were seeded in six well-plates, maintained in culture at 33–34 °C, and warmed daily for three cycles of 1 hour with 1.5 hour intervals. Changes in cell growth and metabolism were determined in sets of triplicate wells by cell counts and a colorimetric assay before and after one week's treatment, After eight days the number of cells indings suggest that the stimulation of cell proliferation induced by intermittent heating in vitro may indicate a possible mechanism contributing to in vivo effects. (WOUND REP REG 2000;8:138–144). [ABSTRACT FROM AUTHOR]

We report liquid/air partition coefficients for dilute solutions of acetaldehyde in water, saline (0.9% wt/vol NaCI), human plasma, and com oil. Equilibrium was studied at 34°C and 37°C with various concentrations of acetaldehyde in the liquid phases. At 37°C, the liquid/air partition ratios for water, saline, plasma, and oil were 143 ± 7.1,132 ± 6.6,183 ± 3.6, and 64 ± 9.9 (means ± SE), respectively. At 34°C, all the values were higher and the temperature coefficients of solubility were 3.7%, 3.3%, and 4.0% per 1°C for water, saline, and plasma solutions of acetaldehyde, respectively. The partition coefficients were independent of the concentration of acetaldehyde in the liquids, and the solubility was higher in water than in oil. The results are discussed with emphasis on the usefulness of expired breath as a biological specimen for the quantitative determination of acetaldehyde. [ABSTRACT FROM AUTHOR]

To realize high-capacity wireless access, the millimeter-wave frequencies have been investigated. Research on indoor multipath propagation has been pursued intensively. This paper proposes an evaluation method for the millimeter-wave indoor high-capacity digital transmission characteristics. First, the broadband propagation characteristics under indoor multipath environment were measured so that the multiple-wave configurations are clarified. Next, to quantify the digital transmission characteristics under the multiple wave environment, the level ratio (D/U) of the desired wave to the interference wave was evaluated for a bit error rate of 10-4 by means of a 4 PSK- 100 Mb/s and a multipath fading simulator. It was found that the bit error rate is determined by the level ratio (D/UT) of the desired wave to the total interference waves and not by the delay time of the interference wave if the delay time of the interference wave exceeds the symbol duration and that the desired D/UT approaches the signal-to-noise (S/N) ratio (N: Gaussian noise) giving such a bit error rate. From the foregoing results, this paper proposes a channel design method using the D/U in indoor high-capacity wireless communication. [ABSTRACT FROM AUTHOR]

It is desirable that the method used for outdoor path loss estimation at microwave frequencies be one for which a worldwide consensus can be obtained through an ITU-R international standard. In this paper, a path loss prediction model for over-rooftop propagation environments is proposed for suburban areas. This model is based on the propagation mechanism explained by using the geometrical optics and consists of the direct wave region, the reflected wave region, and the diffracted wave region. The boundary points of these regions can be determined uniquely from the antenna height and building environment and all regions are continuously connected. Hence, high-precision estimation of the path loss can be estimated from the short-distance line-of-sight region to the far-field non-line-of-sight region. The proposed model is useful for channel design of microwave-band wireless access systems. Further, the method contributes to the ITU-R international standardization described above. Finally, it is shown that the measured path loss and the value estimated by the present model agree well at 2.2, 5.2, and 19.4 GHz. © 2006 Wiley Periodicals, Inc. Electron Comm Jpn Pt 1, 90(1): 13–24, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecja.20333 [ABSTRACT FROM AUTHOR]

5-GHz-band wireless access systems, such as the RLAN (Radio Local Area Network) system of IEEE 802.11a, HiperLAN/2, HiSWANa, and AWA, are deployed for indoor use at transmission rates over 20 Mbps. These 5-GHz access systems are expected to extend service areas from the office to the so-called “hot spots” in public areas. Underground shopping malls are one type of service area where the application of such nomadic wireless access service can be expected. In order to design radio zone configurations, it is necessary to know broadband propagation characteristics of an underground mall environment even if results obtained by previous measurements in the narrow band are available. This paper presents results of an experimental study on the propagation characteristics for broadband wireless access systems in an underground mall environment. First, broadband propagation path losses are measured and formulated considering the shadowing by human body. A ray trace simulation is used to clarify the basic propagation mechanism in such a closed environment. Next, it was determined that values of the delay spread at different distances during rush hour periods did not exceed 65 ns, which is lower than the permitted maximum value of the present 5-GHz systems. The final conclusion is that the above propagation characteristics corroborate results of transmission tests carried out by using the AWA equipment. © 2005 Wiley Periodicals, Inc. Electr Eng Jpn, 152(3): 55–64, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20059 [ABSTRACT FROM AUTHOR]

Abstract: Background:: Voglibose is an α-glucosidase inhibitor used to decrease postprandial hyperglycemia in diabetic patients. Although clinical concern has not yet been raised, hepatic dysfunction has been reported in a few patients taking this drug. Method:: In the present study, we studied the effects of voglibose on the hepatotoxicity of carbon tetrachloride (CCl4) and acetaminophen (APAP) in rats, since both of these agents exert their effects through isoforms of cytochrome P450. Male Sprague–Dawley rats were given a daily ration (20g) of powdered chow diet containing 0, 2.5, 5.0 or 10.0mg/100g of voglibose. Three weeks later, the rats were challenged with either 0.50g/kg CCl4 orally or 0.75g/kg APAP intraperitoneally for biochemical examinations or killed for an in vivo metabolism study. Results:: Voglibose at these three experimental doses potentiated CCl4 and APAP hepatotoxicity, as evidenced by significantly increased levels of both plasma asparate transaminase (AST) and alanine transaminae (ALT). The glutathione (GSH) content was decreased while malondialdehyde (MDA) increased in the liver after CCl4 or APAP administration. Hepatic cytochrome P450 2E1 (CYP2E1) concentration was increased at doses of 5.0 and 10.0mg/100g of voglibose and its activity increased in the three voglibose dosage groups, while hepatic cytochrome P450 3A (CYP3A) and cytochrome P450 1A2 (CYP1A2) were only slightly changed at any dose. Conclusion:: Our study demonstrated that voglibose can potentiate CCl4 and APAP hepatotoxicity in rats by inducing hepatic CYP2E1. [Copyright &y& Elsevier]