Search

Spin-photonic crystals (SPCs) are very promising for applications in modern photonics because they possess an additional degree of freedom. The SPCs can be prepared as periodic one-, two-, and three-dimensional structures composed of, at least, two di erent magnetic and nonmagnetic, or magnetic and magnetic materials with di erent refractive indices. The linear SP properties of one-dimensional SPCs with three-defect asymmetric structures were studied. The requirements of a Kerr rotation of about 45 and a re ectance higher than 95 % are met simultaneously with the 44-layer structure. The frequency response of the re ectance is greatly broadened as the length of the rear structure is increased, without any evident e ect on the Kerr rotation. These conditions are also satis ed at both normal and slightly oblique incidence. In addition, we investigated the nonlinear optical response, including the optical bistability, of a one-dimensional SPC with twodefect layers upon intensive optical radiation in the polar SP con guration for the normal incidence of light. The relationship of defect modes inside the photonic band gap with the number of bilayers between defect layers was obtained. The cubic nonlinear polarization leads to the e ects of optical bistability on the wavelengths of the defect modes.

The adsorption of sodium dodecyl sulfate (SDS) on alumina was studied by using the surfactant ion-selective electrode. The adsorbance could be calculated from the potential and concentration response characteristics of surfactant ion-selective electrode to get surfactant adsorption isotherm. Further experiment results show that the adsorbance was greatly influenced by pH of the solution. It is demonstrated that surfactant ion-selective electrode could be utilized to measure surfactant concentrations in solution after adsorption equilibrium without solid-liquid separation.

Ti-Cx-Ny thin films with different amounts of C incorporated into TiN0.87 were deposited on Si(100) substrates at 500 °C by reactive unbalanced dc magnetron sputtering. Their phase configuration, nanostructure, and mechanical behavior were investigated by x-ray diffraction (XRD), x-ray photoelectron spectroscopy (XPS), high-resolution transmission electron microscopy (HRTEM), and microindentation measurements. The results indicated that the atomic ratio of (C+N)/Ti played a crucial role in phase configuration, nanostructure evolution, and mechanical behavior. When the ratio was less than one, a nanocrystalline (nc-) Ti(C,N) solid solution was formed by dissolution of C into the TiN lattice. Both microhardness and residual compressive stress values increased with an increase of C content. When the C reached saturation, precipitation of small amounts of sp2 amorphous (a-) phase appeared with more C incorporation. Further increase of C content (up to ∼19 at. % C) made the amorphous phase fully wet nanocrysta...

Top emission polymer light-emitting devices (PLEDs) with different heat treatments are investigated. Due to the high work function of an indium–tin-oxide (ITO) cathode as a top electrode, LiF is employed as an interlayer to increase electron injection. The PLEDs fabricated at room temperature show better electrical and optical characteristics such as current density–voltage, luminance, and current efficiency, etc., than that of PLED devices with heat treatment. To investigate the Li diffusion in the polyfluorene layer, X-ray photoelectron spectroscopy measurement before and after heat treatment is performed. The poor performance of PLEDs with heat treatments is observed due to the high trap density generated in the film because of the Li diffusion in the polyfluorene layer.

Several different types of thin films, TiB0.65,TiB0.62N0.18,TiB0.61N1.04, and pure TiN, were deposited on Si(100) substrates at 500 °C by reactive unbalanced close-field dc-magnetron sputtering using two Ti and two TiB2 targets. The oxidation experiments of these films were carried out in air at fixed temperatures in a temperature regime of 600–1000 °C. As-deposited and oxidized films were characterized and analyzed using x-ray diffraction, plan-view and cross-sectional scanning electron microscopies, atomic force microscopy, and x-ray photoelectron spectroscopy (XPS). It was found that the microstructure and bonding configuration of Ti–B–N thin films were strongly dependent on nitrogen flow rate during deposition. Depending upon the amount of N addition, the films showed two- or three-phase nanocomposite structure. Nitrogen-free films were amorphous compound comprising of Ti and TiB2 (Ti–TiB2 compound). At 10 at. % N addition (TiB0.62N0.18), the films consisted of mainly TiN and TiB2 bondings with micros...

An important role of human cytochrome P450s (P450s) has been well recognized in the area of drug metabolism and pharmacokinetics. It has become possible in recent years to express catalytically active forms of these enzymes in various host systems. The resulting recombinant human P450s are either purified for studies of protein structure and the mechanism of catalysis or isolated in microsomal forms to serve the purposes of P450 phenotyping, metabolic stability screening and inhibitory potential evaluation. Intact mammalian cells expressing human enzymes may also be used to test the mutagenic and toxicity potential of drug candidates. The issue remains, however, that the data derived from recombinant P450s are not always consistent with those generated from human tissue preparations. The aim of this communication is to discuss applications of recombinant P450s in the drug discovery and development setting, with an emphasis on comparison of recombinant and human liver microsomal systems.

Diabetes mellitus and dementia, two of the most common disorders in the elderly, are posing a tremendous burden on public health in the society. Moreover, the absolute number and the proportion of older people who are affected by diabetes, borderline diabetes and dementia are expected to further increase over the next few decades. The aim of this study was to determine if a relationship existed between type 2 diabetes and dementia by performing a meta-analysis of published cross-sectional and prospective studies.Comprehensive literature search was performed and the extracted data was analyzed.Our findings highlight the need to detect borderline diabetes and undiagnosed diabetes in order to effectively prevent dementia, as previous studies have shown that prediabetes and diabetes could be improved by interventions addressed towards lifestyle changes and antidiabetic treatment.As far as clinical practice is concerned, it is important to bear in mind that prevention, timely diagnosis, and the optimum treatment of diabetes and borderline diabetes may help to reduce the occurrence of dementia.

This paper presents an outline of a coherent pulse compression–expansion system constructed for an airborne synthetic aperture radar (SAR). The design concept, system performance, and experimental results are presented. Notably, a pair of conjugate surface acoustic wave (SAW) dispersive delay lines is implemented on a Bi12GeO20 substrate for the first time. The Bi12GeO20 substrate is chosen as a good tradeoff between insertion loss and temperature stability. Furthermore, its low acoustic velocity provides the added advantage of being able to use a shorter line to achieve the same time delay. ©2000 John Wiley & Sons, Inc. Microwave Opt Technol Lett 24: 263–267, 2000.

A consensus molecular linkage map of 61.9 cM containing the Or5 gene, which confers resistance to race E of broomrape orobanche cumana, five SCAR markers (three dominant, two codominant) and one RAPD marker were identified based on segregation data scored from two F2 populations of susceptible×resistant sunflower line crosses. Bulked segregant analysis was carried out to generate the five SCAR markers, while the single RAPD marker in the group was identified from 61 segregating RAPD markers that were directly screened on one of the two F2 populations. The five SCAR markers, RTS05, RTS28, RTS40, RTS29 and RTS41, were significantly (LOD≥4.0) linked to the Or5 gene and mapped separately at 5.6, 13.6, 14.1, 21.4 and 39.4 cM from the Or5 locus on one side, while the RAPD marker, UBC120_660, was found at 22.5 cM (LOD=1.4) on the opposite side. These markers should facilitate the efficient transfer of the resistance gene among sunflower breeding lines. As the first report on molecular markers linked to a broomrape resistance gene, the present work provides a starting point to study other genes and to examine the hypothesis of the clustering of broomrape resistance genes in sunflower.

This paper presents an advanced model for the design of stream-lined axisymmetric extrusion dies based on a prescribed strain rate variation. This is vital to the preparation of the workpieces with mechanical properties that are very sensitive to the strain rate distribution during a manufacturing process. The proposed model, which incorporates Tresca’s yield criterion and velocity field with the die angularity, can give an accurate prediction of the die shape. Influences of the interfacial friction and the ram velocity on the die geometry are also studied. As a verification of the proposed model, an updated Lagrangian formulated, elasto-plastic finite element program was developed to analyze the axisymmetric extrusion process. A clear derivation of the load-correction matrix, which is in dispensable for the surface traction rate equilibrium in the updated Lagrangian formulation, is described for the application of the finite element simulation. A friction-correction matrix based on a constant shear law is used to solve the interfacial friction. From the comparison of the resultant strain rate distribution, it verifies that the advanced model can determine the surface angularity and friction force in the extrusion process.

A conserved tyrosine plays a critical role in catalysis by mammalian glutathione S-transferases (GSTs) of the alpha-, mu-, and pi-classes, by forming a hydrogen bond to and stabilizing the thiolate form of glutathione. The hydrogen bonding properties of this tyrosine in the rat A1-1 GST (Tyr-9), in the absence and presence of ligands, have been studied by steady state and time-resolved fluorescence spectroscopy. In order to achieve this, the single tryptophan (Trp 21) found in the rat A1-1 GST has been replaced with the fluorometrically silent phenylalanine (W21F). Additionally, a double mutant lacking this tryptophan and the catalytic tyrosine (W21F:Y9F) has been constructed, and these mutants have been used as probes of ligand effects at Tyr-9. A comparison of the correlated excitation--emission spectra of the W21F mutant and the W21F-Y9F indicates that a red-shifted emission component is contributed by Tyr-9 with excitation bands at 255 and 300 nm, in the ligand-free enzyme. The pH-dependence of the intensity of these spectral cross-peaks is consistent with an active site tyrosine with a pKa of 8.1-8.3. Upon addition of GSH, the red-shifted component is quenched. Multifrequency phase/modulation fluorescence experiments qualitatively demonstrate that GSH causes a decrease in the average excited state lifetime on the red-edge of the spectrum of W21F but not of the W21F:Y9F spectrum. Steady state correlated difference spectra (W21F-W21F:Y9F) have been used to obtain a model for the excitation-emission correlated spectrum of Tyr-9, which indicates that Tyr-9 is heterogeneous at pH 7.5, with properties of both tyrosinate and "normal tyrosine". The tyrosinate fraction is eliminated, and the blue-shifted component becomes more intense upon addition of GSH conjugates, indicating that the weak hydrogen bond between Tyr-9 and thioethers has little charge-transfer character. The S-methyl GSH yields an "anomalous" spectrum at pH 7.5, which retains cross-peaks consistent with ionized tyrosinate. These results indicate that, in the absence of ligand, Tyr-9 forms a strongly polarized hydrogen bond or a fraction of the phenolic hydroxyl group is partially deprotonated. However, when a GSH conjugate with a sufficiently large hydrophobic group occupies the H-site, Tyr-9 is fully protonated, with little charge-transfer character.

The grain growth in two-phase nanocomposite Ti-Cx-Ny thin films grown by reactive close-field unbalanced magnetron sputtering in an Ar-N2 gas mixture with microstructures comprising of nanocrystalline (nc-) Ti(N,C) phase surrounded by amorphous (a-) (C,CNx) phase was investigated by a combination of high-resolution transmission electron microscopy (HRTEM) and Monte Carlo (MC) simulations. The HRTEM results revealed that amorphous-free solid solution Ti(C,N) thin films exhibited polycrystallites with different sizes, orientations and irregular shapes. The grain size varied in the range between several nanometers and several decade nanometers. Further increase of C content (up to ∼19 at.% C) made the amorphous phase wet nanocrystallites, which strongly hindered the growth of nanocrystallites. As a result, more regular Ti(C,N) nanocrystallites with an average size of ∼5 nm were found to be separated by ∼0.5-nm amorphous phases. When C content was further increased (up to ∼48 at.% in this study), thicker amor...

NAD(P)H:quinone oxidoreductase (NQOR; EC 1.6.99.2) is a homodimeric enzyme which catalyzes the reduction of quinones, azo dyes, and other electron acceptors by NADPH or NADH. To pursue subunit functional studies, we expressed a wild-type/mutant heterodimer of NQOR in Escherichia coli. The wild-type subunit of the heterodimer was tagged with polyhistidine and the other subunit contained a His-194-->Ala mutation (H194A), a change known to dramatically increase the Km for NADPH. This approach enabled us to efficiently purify the heterodimer (H194A/HNQOR) from the homodimers by stepwise elution with imidazole from a nickel nitrilotriacetate column under nondenaturing conditions. The composition of the purified heterodimer was confirmed by SDS and nondenaturing polyacrylamide gel electrophoresis and immunoblot analysis. The enzyme kinetics of the purified heterodimer were studied with two two-electron acceptors, 2,6-dichloroindophenol and menadione, and a four-electron acceptor, methyl red, as the substrates. With two-electron acceptors, the Km(NADPH) and Km(NADH) values of the heterodimer H194A/HNQOR were virtually identical to those of the wild-type homodimer, but the kcat-(NADPH) and kcat(NADH) values were only about 50% those of the wild-type homodimer. With the four-electron acceptor, the Km and kcat values of H194A/HNQOR for NADPH and NADH were similar to those of the low-efficiency mutant homodimer. These results suggest that the subunits of NQOR function independently with two-electron acceptors, but dependently with a four-electron acceptor. This heterodimer approach may have general applications for studying the functional and structural relationships of subunits in dimeric or oligomeric proteins.

In this study, Cu wire bonds are aged at 150, 175, 250, and 350 °C for time ranging from 5 min to 2000 h. The top temperature of 350 °C is chosen to have the fastest kinetics, while maintaining the same types of stable intermetallics (IMCs) according to the Al-Cu binary phase diagram. Two types of Cu wire are used, including bare Cu wire and Pd coated Cu wire. To avoid possible damages from conventional mechanical polishing processes, all cross-sections are carried out by using an Ar ion beam cross-section polisher. Observations are carried out using a field-emission scanning electron microscope. The compositions of IMCs are determined by using a state-of the-art field-emission electron microprobe. According to the results of this study, in the as-bonded condition, the IMC formed is CuAl 2 . Its morphology is island-type and covers only a small percentage of the interface. During aging, the growth directions of IMCs are both lateral and perpendicular to the interface. At the lowest temperature (150 °C), the growth of IMCs is very slow. Even after 2000 h of aging, a large portion of Al remains un-consumed, and the IMCs formed are CuAl 2 and CuAl. The growth rate increases very rapidly with temperature. At the highest temperature (350 °C), most of the Al is consumed after only 30 min of aging, and a thick layer of Cu 3 Al 2 form over CuAl and CuAl 2 . Detailed morphological evolutions of IMCs for all temperatures are described. The Pd atoms in Pd-coated Cu wire do not participate in the interfacial reaction, and have no marked effect on the growth rate of IMCs. There is no detectable Pd signal in the IMCs. With the formation of IMCs, the Pd atoms are rejected into Cu in front of the IMCs.

Individual variability in drug efficacy and drug safety is a major challenge in current clinical practice, drug development, and drug regulation. For more than 5 decades, studies of pharmacogenetics have provided ample examples of causal relations between genotypes and drug response to account for phenotypic variations of clinical importance in drug therapy. The convergence of pharmacogenetics and human genomics in recent years has dramatically accelerated the discovery of new genetic variations that potentially underlie variability in drug response, giving birth to pharmacogenomics. In addition to the rapid accumulation of knowledge on genome-disease and genome-drug interactions, there arises the hope of individualized medicine. Here we review recent progress in the understanding of genetic contributions to major individual variability in drug therapy with focus on genetic variations of drug target, drug metabolism, drug transport, disease susceptibility, and drug safety. Challenges to future pharmacogenomics and its translation into individualized medicine, drug development, and regulation are discussed. For example, knowledge on genetic determinants of disease pathogenesis and drug action, especially those of complex disease and drug response, is not always available. Relating the many gene variations from genomic sequencing to clinical phenotypes may not be straightforward. It is often very challenging to conduct large scale, prospective studies to establish causal associations between genetic variations and drug response or to evaluate the utility and cost-effectiveness of genomic medicine. Overcoming the obstacles holds promise for achieving the ultimate goal of effective and safe medication to targeted patients with appropriate genotypes.

Five series of asymmetric diphenyldiacetylenes containing a single fluorine, two fluorines or a trifluoromethyl group at one end and an alkyl, alkyloxy or alkenyloxy group on the other end, were prepared and characterized. Most of the 4-alkylphenyl-4′-fluorophenyldiacetylenes, 4-alkyloxyphenyl-4′-fluorophenyldiacetylenes and 4-alkenyloxyphenyl-4′-fluorophenyldiacetylenes obtained exhibit an enantiotropic nematic phase and no smectic phase. However, most of the 4-alkyl-3′, 4′-difluorodiphenyldiacetylenes, 4-alkenyloxy-3′,4′-difluorodiphenyldiacetylenes and 4-alkyl-4′-trifluoromethyldiphenyldiacetylenes show no mesomorphic behaviour. The effects of alkyl, alkyloxy, alkenyloxy, fluoro, 3,4-difluoro and trifluoromethyl end groups on the mesomorphic behaviour of the diphenyldiacetylenes prepared are discussed.

The rat alpha 1-1 glutathione S-transferase (GST) contains a single, non-essential tryptophan and only 8 tyrosines in each subunit. One of these tyrosines, Tyr-9, hydrogen bonds to the substrate glutathione and stabilizes the nucleophilic thiolate anion. Two mutant proteins that allow for the spectrocopic determination of the pKa of this catalytic residue have been constructed. The W21F mutant provides a fully active GST with no tryptophans, and the double mutant W21F/Y9F lacks both tryptophan and the active site tyrosine. The intrinsic fluorescence and absorbance properties of these mutants are dominated by tyrosine. Fluorescence emission, fluorescence excitation, and absorbance spectral changes of samples containing the W21F mutant at several pH values in the range 6.8-9.0 reveal a pH-dependent increase in the contribution of tyrosinate. No spectral changes are observed with the W21F/Y9F protein in this pH range. At pH 12.5, both proteins exhibit complete deprotonation of all tyrosines. The pKa of Tyr-9 determined from these spectroscopic changes is 8.3-8.5. The changes in absorbance at 250 and 295 nm correspond to titration of 0.95 +/- 0.29 tyrosines/subunit in the W21F protein between pH 6.9 and 9.3. Moreover, addition of the inhibitor S-hexylglutathione results in an apparent increase in the pKa of Tyr-9. Together, these results indicate that the catalytically active Tyr of GSTs has a pKa value that is 1.8-2.0 pKa units below tyrosine in solution. It is likely that this decrease in the pKa of Tyr-9 contributes to catalysis by altering the equilibrium position of the proton shared between Tyr-9 and GSH, and this active site residue may function as a general base catalyst in addition to a hydrogen bond donor.

ZnO2nanoparticles have been synthesized by an organometallic precursor method. The structure, structural stability, and magnetic and optical properties of ZnO2 nanoparticles have been investigated ...

The nanostructures and mechanical properties of nanocomposite nc-TiN/a-(TiB2, BN) and nanostructured multilayers nc-TiN/a-TiBN were investigated using X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), microindentation, and stress measurements. It was found that the monolayer Ti-B-N thin films consisted of nanometer-sized crystalline (nc-) Ti(N, B) embedded into amorphous (a-) (TiB2, BN) matrix. When B content was below approximately 16 at.%, two different-sized nanocrystallites with mean grain sizes of approximately 3 and 9 nm respectively were embedded in a-TiB2. With increasing B incorporation (approximately 27 at.%), more uniform nanograins was embedded a-(TiB2, BN). Incorporation of B not only decreased the size of nanocrystallites, but also gave rise to twinning deformation in nanocrystallites. A maximum hardness of approximately 44 GPa was achieved at B content of 19 at.%. It was also found that the nanostructure and mechanical behaviors of nc-TiN/a-TiBN multilayers was dependent on the modulation length (bilayer thickness A). Decrease of Lambda made the preferred orientation of nc-TiN gradually transform from (200) to (111). A maximum hardness of approximately 30 GPa was achieved at Lambda = 1.8 nm. Deflection from this Lambda value decreased hardness. By contrast, the residual compressive stress value monotonically increased with decrease of A. The enhancement of the hardness was due to the coherent stresses and the structural barriers to dislocation motion in the interface.

CYP1A1 and 1A2 play critical roles in the metabolic activation of carcinogenic polycyclic aromatic hydrocarbons (PAHs) and heterocyclic aromatic amines/amides (HAAs), respectively, to electrophilic reactive intermediates, leading to toxicity and cancer. CYP1As are highly inducible by PAHs and halogenated aromatic hydrocarbons via aryl hydrocarbon receptor-mediated gene transcription. The impact of CYP1A induction on the carcinogenic and toxic potentials of environmental, occupational, dietary, and therapeutic chemicals has been a central focus of human risk evaluation and has broadly influenced the fields of cancer research, toxicology, pharmacology, and risk assessment over the past half-century. From the early discovery of CYP1A induction and its role in protection against chemical carcinogenesis in intact animals, to the establishment of CYP1A enzymes as the principal cytochromes P450 for bioactivation of PAHs and HAAs in in vitro assays, to the recent realization of an essential protective role of CYP1A in benzo[a]pyrene-induced lethality and carcinogenesis with CYP1A knockout mice, the understanding of the interrelation between CYP1A induction and chemical safety has followed a full circle. This unique path of CYP1A research underscores the importance of whole animal and human studies in chemical safety evaluation.

A space experiment on bubble behavior and heat transfer in subcooled pool boiling phenomenon has been performed utilizing the temperature-controlled pool boiling (TCPB) device both in normal gravity in the laboratory and in microgravity aboard the 22nd Chinese recoverable satellite. The fluid is R113 at 0.lMPa and subcooled by 26°C nominally. A thin platinum wire of 60µm in diameter and 30mm in length is simultaneously used as heater and thermometer. Only the lateral motion and the departure of discrete vapor bubbles in nucleate pool boiling are reported and analyzed in the present paper. A scale analysis on the Marangoni convection surrounding a bubble in the process of subcooled nucleate pool boiling leads to formulas of the characteristic velocity of the lateral motion and its observability. The predictions consist with the experimental observations. Considering the Marangoni effect, a new qualitative model is proposed to reveal the mechanism underlying the bubble departure processes and a quantitative agreement can also be acquired.

Individual variability in cytochrome P450 (P450) induction comprises an important component contributing to the difficulties in assessing and predicting metabolism-based drug-drug interactions in humans. In this article, we outline the major factors responsible for the individual variability in P450 induction, including variable transporter activity and metabolism of inducers in vivo, genetic variations of P450 genes and their regulatory regions, genetic variations of receptors and regulatory proteins required for induction, and different physiological and environmental elements. With a better understanding of the major determinants in P450 induction and a profile of the phenotypes of these determinants in each individual, it is believed that the individual variability in induction-mediated drug-drug interactions can be adequately evaluated.

The 20-year period long-term results of porcine bioprosthetic valve use are limited. In addition, the majority of these reports come from Western countries. Given the scanty information reported in Oriental countries, this study was therefore designed to examine 20-year long-term results in patients who received a Carpentier-Edwards porcine bioprosthetic valve in an effort to contribute further information on the long-term clinical performance of porcine prosthetic valves from a viewpoint of results in the Oriental population.From July 1979 to April 2001, 82 patients received valve replacement with a standard Carpentier-Edwards porcine valve. There were 40 men and 42 women with a mean age of 42.3+/-15.1 years (range 16 to 73 years). Follow-up time extended more than 20 years (mean 10.9+/-3.2 years, range 0.5 to 21.5 years ) for a total of 719.5 patient-years.The overall operative mortality was 16.9% (14 of 83 procedures). At 5, 10, 15, and 20 years, the actuarial survival rate of patients was 71.7%, 66.9%, 55.5%, and 44.4%, respectively. Actuarial estimates of freedom from structural valvular deterioration (SVD) at 5, 10, 15, and 17 years were 96.3%, 64.0%, 24.3%, and 24.3%, respectively; from reoperation 96.3%, 64.5%, 24.5%, and 24.5%; from operated valvular endocarditis 96.8%, 92.6%, 92.6%, and 92.6%; and from overall thromboembolism 96.3%, 88.5%, 67.2%, and 52.2%. In normal sinus rhythm, actuarial estimates of freedom from thromboembolism at 5, 10, 15, and 17 years were 100.0%, 100.0%, 81.8%, and 81.8%, respectively. Whereas for those in patients with atrial fibrillation, the estimates of freedom from thromboembolism were 94.5%, 82.4%, 57.7%, and 38.5%.This study demonstrates the very satisfactory 20-year period long-term performance of freedom from bleeding events, thromboembolism (except in patients with atrial fibrillation), and valvular endocarditis in Oriental patients undergoing replacement with a porcine valve. However, the remarkable rate of SVD and reoperation ensued at 6 years after bioprosthesis implanted which does not differ from the series reported from Western countries.

A quick and effective extraction and clean-up method of profenofos residue in tomato and cabbage is presented. Tomato and cabbage samples were homogenized with a mixture of acetone-hexane (1:1, V/V) using a mechanical homogenizer. The resultant homogenate was cleaned-up by adding active carbon and then filtered under reduced pressure. The filter cake was extracted twice with the same solvent mixture. The filtrates were combined and transferred into a separatory funnel. The organic layer was separated and evaporated to dryness using a rotary evaporator. The residue was dissolved in 2 mL of acetone and transferred into a small glass vial and then determined by GC on a 5% OV-101 Chromosorb W-HP column with flame photometric detector. The results showed that this analytical method can be used for an accurate determination of profenofos residues in tomato and cabbage. The minimum detectable concentration of profenofos in samples was 0.06 mg/kg. The recoveries of profenofos in tomato and cabbage were in the range of 96.2%-105.9% and 94.7%-102.3%, respectively. The relative standard deviations were in the range of 3.7%-4.9% and 3.7%-5.0%, respectively. The tomato and cabbage samples were collected 3 weeks after applying profenofos in the field, and the contents of profenofos were determined. The average contents of profenofos in tomato and cabbage were (13.8 +/- 0.8) mg/kg and (14.4 +/- 0.7) mg/kg, respectively.

Myxoma is the most common primary tumor of heart. The typical picture of myxoma under echocardiography is a solid, dense echo mass and left atrium is the most common site to find it. The cystic form of myxoma is vary rare. We report a patient who received echocardiographic examination under impression of mitral valve stenosis. A multilobulated cystic mass which was like a hydatid cyst was found in the left atrium and atrioventricular flow was affected by this mass. After tumor resection, myxoma with internal hemorrhage was proved by pathology. No further recurrent myxoma was found during follow-up echocardiographic examination.

The Kearns-Sayre (K-S) syndrome which includes the triad of progressive external ophthalmoplegia, pigment retinopathy, and disorder of cardiac conduction was first described in 1958. The mitochondria disorder is believed to be the cause of this syndrome. Involvement of the cardiac conduction system is the most importent prognostic factor in K-S syndrome. A 34-year-old male K-S syndrome patient, manifesting as ptosis and weakness of limbs since the age of 15 years, suffered from dizziness and weakness. Twelve-lead eletrocardiography (ECG) showed a 2:1 atrioventricular (AV) block with slow ventricular rate. Intermittent complete AV block, complete left bundle branch block and torsades de pointes were noted in Holter ECG. The electrophysiology study demonstrated prolonged HV interval (85 ms) on conduction beat and infra-His block on non-conduction beat. A VVIR mode of permanent pacemaker was implanted and the patient's condition was stable during this period of follow-up.

Several studies have shown cardiovascular benefit in treating hypercholesterolemia with HMG-CoA reductase inhibitor. However, in addition to the lowering of cholesterol, the beneficial effects of this inhibitor reflect other pharmacological activities. Whether these beneficial effects are partly mediated by changes in fibrinolytic factors remains to be proven, since clinical studies on the effects of HMG-CoA reductase inhibitors on fibrinolytic factors have not yielded consistent results. The purpose of this study was to evaluate the effects of fluvastatin on fibrinolytic factors in hypercholesterolemic patients. After 6 weeks on a low-fat, low-cholesterol diet, 23 outpatients known to have primary hypercholesterolemia with low density lipoprotein cholesterol (LDL-C)or = 130 mg/dl with at least 2 risk factors or fasting LDL-Cor = 160 mg/dl were selected for the study. Venous blood samples were collected at baseline and at 8 weeks after fluvastatin therapy (40 mg/day) to measure of tissue plasminogen activator (t-PA), plasminogen activators inhibitor-1 (PAI-1), fibrinogen, D-dimer and lipid profile. After 8 weeks of therapy, fluvastatin reduced serum cholesterol by 11% (261.9 mg/dl vs 233.2 mg/dl, P0.01) and LDL-C by 22% (191.9 mg/dl vs 149.3 mg/dl, P0.01). D-dimer was significantly decreased (0.38 ng/L vs 0.28 ng/L, P = 0.02) and tPA, PAI-1 and fibrinogen tended to decrease after therapy. Fluvastatin therapy improved fibrinolytic profile; the result of this study may in part explain the benefit of HMG-CoA reductase inhibitor on cardiovascular system other than lipid lowering.

Drug interactions have always been a major concern in medicine for clinicians and patients. Inhibition and induction of cytochrome P450 (CYP) enzymes are probably the most common causes for documented drug interactions. Today, many pharmaceutical companies are predicting potential interactions of new drug candidates. Can in vivo drug interactions be predicted accurately from in vitro metabolic studies? Should the prediction be qualitative or quantitative? Although some scientists believe that quantitative prediction of drug interactions is possible, others are less optimistic and believe that quantitative prediction would be very difficult. There are many factors that contribute to our inability to quantitatively predict drug interactions. One of the major complicating factors is the large interindividual variability in response to enzyme inhibition and induction. This review examines the sources that are responsible for the interindividual variability in inhibition and induction of cytochrome P450 enzymes.

Attempts were made to isolate the bacteria from toxic dinoflagellate Alexandrium minutum T1 and to study the effect of these bacteria on the growth and toxicity of A. minutum T1. It was found that intracellular bacterial species including Pasteurella haemolytica, Pseudomonas vesicularis, and Sphingomonas sp., and extracellular bacterial species including Pasteurolla pneumotropica, Morganella wisconsensis, Flavobacterium oryzihabitans, Pseudomonas pseudomallei, and Sphingomonas sp. All of them were cultured and determined to have non-PSP-producing ability. The maximum cell number of A. minutum cultured without isolated bacteria was higher than that cultured with isolated bacteria. The total toxicity of A. minutum cultured with bacteria was similar to that of A. minutum T1 cultured without bacteria from lag phase to stationary phase, but it was lower after stationary phase. The growth of A. minutum T1 cultured without antibiotics was also better than that cultured with antibiotics. The total toxicity of A. minutum cultured without antibiotics was higher than that of A. minutum cultured with antibiotics. However, the cell toxicity of A. minutum did not decrease even if the culture medium was added with antibiotics.

Some improvements made to overcome the difficulty in the long distance perfusion, temperature maintenance, oxygen supply and the recollection of perfused fluid were described in our Langendorff perfusion in combination of NMR technique with which the rhythmic activity of isolated rat heart can be measured as long as 90 min.

Two groups of mice were fed with either hedgehog hydnum powder or extract for sixty days. For the assay of fatigue, the activity of serum lactate dehydrogenase, the serum urea nitrogen content, blood lactic acid, hepatic and muscular glycogen, and the physical stamina of the mice were determined. The activity of serum lactate dehydrogenase and the hepatic and muscular glycogen content in the experimental mice were evidently higher than that in the control mice (P0.05 or P0.01). After exercise, the increase in blood lactic acid and serum urea nitrogen in the experimental mice was significantly lower than that in the control mice (P0.05 or P0.01), but the rate of elimination of blood lactic acid in the experimental mice was significantly higher than that in the control mice (P0.05). In the physical stamina swimming, the experimental mice drowned after a longer period of time than the control mice (P0.05). In conclusion hedgehog hydnum had a significant effect on raising physical stamina and delaying fatigue in mice.

An 81-year-old patient who developed consciousness change and progressive right limb weakness after low abdominal surgery is reported. Brain computed tomography scan showed a left-sided chronic subdural hematoma; appropriate management was instituted immediately. This case is a reminder of the possibility of chronic subdural hematoma in elderly patients who may develop stroke-like symptoms after non-neurosurgical procedures.

The glutathione S-transferases (GSTs) are a family of proteins that conjugate glutathione, via the sulfur atom of cysteine, to various electrophiles (Boyland and Chasseaud 1969; Chasseaud 1979; Jacoby 1978; Mannervik 1985; Mannervik and Danielson 1988; Pickett and Lu 1989; Coles and Ketterer 1990; Armstrong 1991; Tsuchida and Sato 1992). In addition to the conjugation of electrophiles, the GSTs bind with high affinity a variety of hydrophobic compounds such as heme, bilirubin, polycyclic hydrocarbons, and dexamethazone (Litwack et al. 1971; Arias et al. 1976; Bhargava et al. 1980; Homma a n d Listowsky 1985).

Introduction: Children with school refusal have the trait of excessive sensitivity to interpersonal relationship. The trait may have an early onset and persist. The children with school refusal are in the state of tension. They feel terrible anxiety about school itself. The anxiety is increasing during school refusal period. To prevent school refusal, we would like to investigate the feelings of children toward school and peers. Methods: Subjects were 118 Japanese children (6–13-year-old). We made the “Questionnaire on anxiety about school” which consisted of 9 items. These items were taken from the type of feelings described by school refusing children attending our clinic. The subjects were asked to rate each item as 0: not at all, 1: a little, 2: deeply, or 3: overly. Additionally, they were asked whether they were in distress at attending school. Results: Factor analysis was performed on the 9 item scores of the Questionnaire. One factor was named as anxiety about school, 5 items loaded highly on the factor; the other was named as excessive interpersonal sensitivity, 4 items loaded highly on the factor. These were entered into logistic regression to determine their association with distress at attending school. Age, sex, sum of the items of school anxiety, and sum of the items of interpersonal sensitivity were analyzed as independent variables. Interpersonal sensitivity had significant association with distress at attending school (Odds ratio = 1.32; 95% Wald confidence limits: 1.05–1.66). Conclusion: We can intervene by influencing the trait of excessive interpersonal sensitivity in these children.

A novel alkaloid, named hypodematine, was isolated from Hypodematium sinense Iwatsuki (belonging to the lypterdaceae). Its structure has been elucidated to have a novel skeleton of benzo-aza-cyclooctatetraene with a phenyl substitution by means of the 1H-1H COSY, 1H-13C COSY and long-range 1H-13C COSY spectroscopy.

This paper presents the preparation of eleven 2, 4 or 6, 7-substituted porphyrine derivatives II-XII from I or diethyl ether of IV. The effects of these compounds, with irradiation, on DNA synthesis in L1210 cells were studied. The results showed that (1) all of these compounds were effective while (2) Va or Vb, VI and VII were more effective.

This paper shows an exact formula of mutual inductance (MI) emploied special functions, and points out that the result from Carson’s formula is better than that from Pollaczek’s formula under the conditions of small distance between wires and small earth conductivity. Finally by using special functions, the method to determine the MI between three phase power lines and a communication line is given.

An approach named the defect-induced extension of photonic band gaps (PBGs) is proposed, in which a stratified periodic structure is combined with another stratified structure containing defect layers. For comparison, three structures composed of TiO2 and SiO2 alternating layers, perfect, five-defect and combined-photonic crystals (PCs), were fabricated by using an electron-beam evaporation system. The measured PBG width of combined-PCs extended to 370 nm at the normal incidence, nearly three times more than that of perfect ones, 130 nm, but a few ripples are observed within the PBG. In order to elucidate the origin of the ripples, the influence of the refractive-index contrast on the reflectance was analyzed theoretically. When the refractive-index contrast nH∕nL≥1.7, the ripples are eliminated. More importantly, an overdoubled omnidirectional PBG is realized at nH∕nL=2.56, covering the visible region completely. This approach is considered to be based on the light localization and a heterostructure resu...

A dimerlike-positional-correlation heterostructure is used in one-dimensional photonic crystals to introduce the defect mode with perfect transmittance. The switching behavior of the transmittance, at the defect mode, is demonstrated theoretically. When the normal incident beam is tilted at a negligibly small angle, the perfect transmittance peak vanishes. It is found that this condition causing this phenomenon can be easily met and controlled through elucidation on the mechanism. This finding is significant for potential applications in high-precision filters and optical switches.

A homeotropic LCD using polymer stabilization and gibbous boundaries has been developed. Multi-domain structures are created by using specially designed pixel boundaries and polymer network. Hence, the rubbing process is no longer employed. This display has demonstrated excellent properties of wide viewing angle and fast response.