Library

Notes: QT dispersion (QTd) represents the inhomogeneity of ventricular repolarization and has been reported to predict ventricular tachyarrhythmias in postmyocardial infarction patients. This study investigates the short-term effect of percutaneous transluminal coronary angioplasty (PTCA) on QTd in patients with coronary artery disease (CAD) and no history of previous myocardial infarction.〈section xml:id="abs1-2"〉〈title type="main"〉MethodsIn 84 angina patients (65 men and 19 women, mean age, 58.3 ± 9.0 years) who underwent successful PTCA of a single coronary artery, ECG was recorded in baseline, immediate, 1 day, and 1 month after PTCA for measurement of QTd and corrected QTd (c-QTd).〈section xml:id="abs1-3"〉〈title type="main"〉ResultsPTCA was performed at the left anterior descending artery (LAD) in 56, left circumflex artery (LCx) in 12, and right coronary artery (RCA) in 16 patients. QTd (c-QTd) at baseline, immediately, 1 day, and 1 month following PTCA was 51.3 ± 4.2 (50.7 ± 4.1), 54.2 ± 4.5 (52.8 ± 4.5), 47.7 ± 4.3 (48.5 ± 4.8), and 36.3 ± 4.5 (37.5 ± 4.6) ms, respectively. QTd and c-QTd significantly decreased at 1 month following PTCA. The difference was more prominent in patients with LAD lesion than LCx or RCA lesion, independent of gender, severity of stenosis, and use of beta-blocker.〈section xml:id="abs1-4"〉〈title type="main"〉ConclusionsQTd decreases in CAD patients with no history of myocardial infarction at 1 month following successful PTCA. This suggests that PTCA facilitates a favorable recovery from inhomogeneous repolarization due to myocardial ischemia. This finding calls for long-term follow-up of QTd and risk of ventricular tachyarrhythmias and sudden death following successful PTCA.

Notes: We report the photovoltaic properties of the donor–acceptor composite system of poly (p-phenylenevinylene) (PPV) and viologen. We observed the significant enhancement of photocurrent with increasing the doping ratio of viologen. The maximum photocurrent of viologen-doped PPV was nine times as high as that of the pristine PPV. The maximum quantum yield and photosensitivity are 13% (electron/photon) and 0.05 A/W, respectively, at low bias voltage (−2 V). The increase of photocurrent is explained with the efficient charge separation that resulted from the transfer of photoexcited electrons from PPV to viologen. The mixture of PPV and viologen can be used as a sensitive photodiode material. © 1998 American Institute of Physics.

Notes: We fabricated a homeotropically aligned nematic liquid crystal display with positive dielectric anisotropy, whose on and off states are controlled by in-plane field. The rubbing-free device, dark in voltage-off state, reveals bright uniformity in all directions due to the dual domainlike director configuration in the voltage-on state. The electro-optic characteristics of one prototype with excellent viewing angles are reported herein. © 1997 American Institute of Physics.

Notes: The temporal and spatial regulation of chitin synthesis plays an important role in morphogenesis during fungal growth and development. Northern blot analysis showed that the transcription level of chsA, chsC, and chsD was significantly decreased in an Aspergillus nidulans abaA mutant. Electrophoretic mobility shift assays revealed that AbaA bound tightly to all three AREs (AbaA response elements) in the chsC promoter region. Experiments with the Saccharomyces cerevisiae heterologous expression system confirmed AbaA-dependent transcriptional activation of chsC. Taken together, these data suggest that AbaA plays an important role in chitin biosynthesis during conidiophore development by controlling the transcription level of certain chitin synthase genes.

Notes: Background A disintegrin and metalloprotease 33 (ADAM33) is expressed in the lung by fibroblasts and bronchial smooth muscle cells. Given its structure and cellular provenance, ADAM33 may be associated with airway remodelling and bronchial hyper-responsiveness. Single nucleotide polymorphisms (SNPs) and haplotypes of the ADAM33 gene have previously been associated with asthma susceptibility in the Caucasian population.Objective and Methods To assess whether genetic variants of ADAM33 are related to asthma in a Korean population, we conducted an association study of the ADAM33 gene with asthma susceptibility, bronchial hyper-reactivity and serum IgE in Korean asthmatics (n=326) and normal controls (n=151). Five of the 14 polymorphisms originally reported to be associated with asthma development (S1 G〉A, T1 T〉C, V-1 C〉A, V1 T〉A, V4 C〉G) were genotyped using single base extension and electrophoresis. Haplotypes and their frequencies were inferred using the algorithm implemented by the software Arlequin. Allele frequencies of each SNP and haplotypes were compared between the patients and the normal controls using logistic regression analysis.Results There was no significant difference in the distribution of SNPs and the six haplotypes between asthmatics and normal controls. All single SNPs and six haplotypes in ADAM33 were also analysed for the association with level of PC20 using general linear models. The distribution of the T1 T〉C SNP and one haplotype (ht4: GCGG) showed significant association with log-transformed PC20 methacholine level in the asthma patients (P=0.03 and 0.0007, respectively, using a co-dominant model).Conclusion Polymorphism of ADAM33 may contribute to development of BHR in asthma.

Notes: The role of nitric oxide (NO) needs to be further clarified in allergic inflammation. This study was designed to investigate the relationships between NO metabolites and eosinophil count, eosinophil cationic protein (ECP), interleukin (IL)-5 in induced sputum from asthmatics.〈section xml:id="abs1-2"〉〈title type="main"〉MethodsHypertonic saline-induced sputum was obtained in 25 asthmatic subjects, among which 13 patients were examined before and after anti-asthmatic medications including steroid preparations. Ten normal subjects were enrolled as controls. Fresh expectorated sputum separated from saliva was treated with equal volume of dithiothreitol 0.1%, cytospined for cell count, and the supernatant was collected for biochemical assay. NO metabolites were assayed by using modified Griess reaction. ECP was measured by fluoroimmunoassay, and detected IL-5 by a sandwich ELISA.〈section xml:id="abs1-3"〉〈title type="main"〉ResultsAsthmatic subjects, compared with controls, had significantly higher concentration of NO metabolites (1035.4 ± 125.3 vs 557.2 ± 101.5 μmol/L, P 〈 0.01), higher percentage of eosinophils (25.6 ± 4.6 vs 1.7 ± 0.2%, P 〈 0.01), and higher levels of ECP (1117.8 ± 213.9 vs 154.6 ± 47.4 μg/L, P 〈 0.01) in the induced sputum. IL-5 was detected more frequently in asthmatic subjects than in control subjects (11/25 [44%] vs 1/10 [10%], P 〈 0.05). According to asthma severity, moderate to severe asthmatic subjects (n = 18) had higher level of NO metabolites (1143.8 ± 156.3 vs 575.5 ± 89.5 μmol/L, P 〈 0.01), higher levels of ECP and IL-5 (P 〈 0.01, respectively) in the induced sputum than in those of mild asthmatic subjects (n = 7). NO metabolites, the percentage of eosinophils, the levels of ECP, and IL-5 were reduced following treatment with anti-asthmatic drugs (P 〈 0.01, respectively). There were significant positive correlations between NO metabolites and percentage of eosinophils or ECP (r = 0.34, P 〈 0.05; r = 0.28, P 〈 0.05). Negative correlations were noted between FEV1, FEV1/FVC and proportion of eosinophils, ECP, or IL-5 levels.〈section xml:id="abs1-4"〉〈title type="main"〉ConclusionThese findings confirmed that the level of NO metabolites was increased in the tracheobronchial secretion of asthmatic subjects and was paralleled with severity of asthma. Measurement of NO metabolites in induced sputum may be used for monitoring the degree of airway inflammation in asthmatics.

Notes: The inactivation kinetics of food poisoning microorganisms using a combined treatment of carbon dioxide (CO2) with high hydrostatic pressure (HHP) was investigated. Staphylococcus aureus, Fusarium oxysporum, and Fusarium sporotrichioides were totally inactivated by a combined treatment of carbonation and HHP at 500 MPa. Bacillus subtilis, a spore forming bacteria, were not completely inactivated after the combined treatment. The microorganisms treated by carbonation and HHP were exponentially reduced in a pressure range and the Dp -value, the Zp-value, and the activation volume were determined. UV absorbing materials leaked from injured cells. Morphological changes of the cells were observed by scanning and transmission electron microscopy.

Notes: 1. The present study was undertaken in order to examine the effect of various oestrogens on tert-butyl hydroperoxide (t-BHP)-induced cell injury and changes in apical transporters in primary cultured rabbit renal proximal tubule cells.2. Compared with control, t-BHP (0.5 mmol/L; 1 h) decreased cell viability (62%) and glutathione (GSH) content (60%) and increased lipid peroxide (LPO) formation (309%), arachidonic acid (AA) release (193%) and Ca2+ influx (168%).3. The protective potency of various oestrogens for these parameters is dependent on the precise oestrogenic structure, with 2-hydroxy-oestradiol-17β (2-OH-E2) and 4-OH-E2, both catecholic oestrogens, or diethylstilbesterol (DES) being more potent than oestradiol (E2), oestriol or oestradiol-17α, all phenolic oestrogens (P 〈 0.05).4. These cytoprotective effects of oestrogens occur at concentrations above 10 μmol/L and are not dependent on classical oestrogen receptors and gene transcription and translation. In addition, various oestrogens have different preventative effects against t-BHP-induced inhibition of [14C]-α-methyl-D-glucopyranoside (α-MG), inorganic phosphate (Pi) and Na+ uptake, consistent with the results of cell injury. In contrast, the potency against t-BHP-induced changes in cell viability, LPO, GSH content and transporter function of the anti-oxidants taurine and vitamin C is similar to that of phenolic oestrogens, whereas that of the iron chelators deferoxamine and phenanthroline is similar to that of catecholic oestrogens.5. In conclusion, various oestrogens have differential cytoprotective potential against t-BHP-induced cell injury and decreases in α-MG, Na+ and Pi uptake. These effects are due, in part, to both the basic chemical properties of the compounds and the maintenance of endogenous GSH or inhibition of AA release and Ca2+ influx.

Notes: [Auszug] Cold induces expression of a number of genes that encode proteins that enhance tolerance to freezing temperatures in plants. A cis-acting element responsive to cold and drought, the C-repeat/dehydration-responsive element (C/DRE), was identified in the Arabidopsis thaliana stress-inducible genes ...

Notes: Abstract A distributed feedback (DFB) laser module has been developed for 2.5 Gbs-1 optical transmission systems. The DFB laser has a multiple-quantum-well (MQW) active layer and a planar buried heterostructure (PBH) for a low threshold current and stable singlemode operation with low chirping. A PBH DFB laser module with a single-mode fibre pigtail and an optical isolator was designed and fabricated by employing a single lens and a laser welding method. The fabricated MQW PBH DFB laser module is shown to be a suitable light source for 2.5 Gb s-1 optical transmission systems with a minimum received power of-33 dBm after 47 km conventional optical fibre transmission.