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M Level (m + level)
Selected AbstractsSeparation and Detection of Nitrophenols at Capillary Electrophoresis Microchips with Amperometric DetectionELECTROANALYSIS, Issue 2 2006Jan Fischer Abstract A miniaturized analytical system for the separation and amperometric detection of toxic nitrophenols, based on the coupling of a micromachined capillary electrophoresis (CE) chip with a glassy carbon detector is described. This microsystem enables a rapid (120,s/sample) simultaneous determination of five priority nitrophenolic pollutants (2-nitrophenol, 3-nitrophenol, 4-nitrophenol, 2,4-dinitrophenol, and 2-methyl-4,6-dinitrophenol). These compounds can be detected down to the 1×10,5,M level using a 15,mM phosphate buffer pH,7.2 (containing 1.3,mM ,-cyclodextrin) as running solution on 77,mm long microchannel by applying a separation voltage of 3000,V and a negative potential of ,0.7,V (vs. Ag /AgCl wire). Applicability to ground water samples was demonstrated. [source] Concurrent de novo autoimmune hepatitis and recurrence of primary biliary cirrhosis post,liver transplantationLIVER TRANSPLANTATION, Issue 5 2001Chee Kiat Tan FRCP (Edin) Primary biliary cirrhosis (PBC) is well known to recur after liver transplantation (LT). The recurrence is usually subclinical and evident only on histological examination. Recently, a new entity of de novo autoimmune hepatitis (AIH) has emerged that occurs after LT in patients who underwent transplantation for diseases other than AIH. This new condition occurs more often in children; however, there was a recent report of the first 2 cases in adults who originally underwent LT for PBC. We report the first case of concurrent de novo AIH and recurrence of PBC documented on the liver biopsy of an adult patient who underwent LT for end-stage PBC. Unlike the earlier report of 2 adults, our patient manifested an antinuclear antibody titer of more than 1/800 from a previously negative titer pre-LT, as well as fulfilled the International AIH Group criteria for a definite diagnosis of AIH. PBC recurrence was evidenced by typical florid duct lesion, antimitochondrial antibody titer increasing from 1/40 to greater than 1/800, and an elevated serum immunoglobulin M level. After the addition of azathioprine to baseline immunosuppression of tacrolimus and prednisolone, the patient responded rapidly, with complete normalization of liver test results. [source] Immune response, disease resistance and intestinal microflora of juvenile Jian carp (Cyprinus carpio var. Jian) fed graded levels of pantothenic acidAQUACULTURE NUTRITION, Issue 4 2010Z.-P. WEN Abstract This study was to investigate the effect of dietary pantothenic acid (PA) on the disease resistance, immune response and intestinal microflora on juvenile Jian carp (Cyprinus carpio var. Jian). Seven diets (4.0, 15.5, 25.6, 36.1, 45.9, 56.1 and 65.9 mg PA kg,1) were fed to Jian carp (12.95 ± 0.03 g) for 9 weeks. After 9-week feeding trial, the challenge experiment with Aeromonas hydrophila was conducted to determine the impact of PA on fish disease resistance. Survival rate after challenge was promoted with the increasing PA levels (P < 0.05). Blood counts also significantly increased up to the dietary PA level of 25.6 mg PA kg,1 (P < 0.05). Leucocyte phagocytic activity, lectin potency, lysozyme and acid phosphatase activity, and total iron-binding capacity were improved with increasing PA levels (P < 0.05). Serum immunoglobulin M level and agglutination antibody titre to A. hydrophila were increased (P < 0.05) in fish fed the diets with the dietary PA levels between 56.1 and 65.9 mg kg,1. PA also promoted the growth and reproduction of Lactobacillus and depressed Escherichia coli and A. hydrophila (P < 0.05). These results suggested that pantothenic acid could improve disease resistance, immune response, and the balance of intestinal microflora in juvenile Jian carp. [source] Modulation of cell adhesion and viability of cultured murine bone marrow cells by arsenobetaine, a major organic arsenic compound in marine animalsBRITISH JOURNAL OF PHARMACOLOGY, Issue 1 2001Teruaki Sakurai In this study, we investigated the biological effects of trimethyl (carboxymethyl) arsonium zwitterion, namely arsenobetaine (AsBe), which is a major organic arsenic compound in marine animals using murine bone marrow (BM) cells and compared them with those of an inorganic arsenical, sodium arsenite, in vitro. Sodium arsenite showed strong cytotoxicity in BM cells, and its IC50 was 6 ,M. In contrast, AsBe significantly enhanced the viability of BM cells in a dose-dependent manner during a 72-h incubation; about a twofold increase in the viability of cells compared with that of control cells cultured with the medium alone was observed with a ,M level of AsBe. In morphological investigations, AsBe enhanced the numbers of large mature adherent cells, especially granulocytes, during a 72-h BM culture. When BM cells were cultured together with AsBe and a low dose (1 u ml,1) of recombinant murine granulocyte/macrophage colony-stimulating factor (rMu GM-CSF), significant additive-like increasing effects were observed on the numbers of both granulocytes and macrophages originated from BM cells. However, AsBe did not cause proliferation of BM cells at all as determined by colony-forming assay using a gelatious medium. These findings demonstrate the unique and potent biological effects in mammalian cells of AsBe, a major organic arsenic compound in various marine animals which are ingested daily as seafood in many countries. British Journal of Pharmacology (2001) 132, 143,150; doi:10.1038/sj.bjp.0703790 [source] Adsorptive Stripping Voltammetric Determination of Amitrole at a Multi-Wall Carbon Nanotubes Paste ElectdrodeELECTROANALYSIS, Issue 5-6 2005M. Chicharro Abstract This work reports the excellent electrocatalytic activity of carbon nanotubes paste electrodes (CNTPE) prepared by dispersion of multi-wall carbon nanotubes (MWNT) within mineral oil toward the oxidation of 3-amino-1H -1,2,4-triazole (amitrole). The quantification is performed by adsorptive stripping voltammetry (AdSV). The influence of the paste composition and surface pretreatments as well as the amitrole accumulation conditions on the adsorption and further electrooxidation of this herbicide is described. After potentiodynamic pretreatment in 0.050,M phosphate buffer pH,7.4 the amitrole oxidation signal shifts 250,mV toward more negative potential and the sensitivity increases 29 fold, demonstrating that pretreated CNTPEs are extremely useful for a highly sensitive determination of amitrole down to the sub-,M levels. The oxidation peak current is proportional to the amitrole concentration over the range from 0.8 to 7.0,,M (5,min accumulation), with a detection limit of 0.6,,M (48,,gL,1) and a precision of 4.3%, n=20. The proposed method was used for the determination of amitrole in spiked river water (Alberche River (Madrid, Spain)) and tap water samples (Madrid, Spain) at levels higher than 0.6,,M. [source] Influence of hypobaric hypoxia on bispectral index and spectral entropy in volunteersACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 7 2009T. IKEDA Background: Hypoxia has been shown to change electroencephalogram parameters including frequency and amplitude, and may thus change bispectral index (BIS) and spectral entropy values. If hypoxia per se changes BIS and spectral entropy values, BIS and spectral entropy values may not correctly reflect the depth of anaesthesia during hypoxia. The aim of this study was to examine the changes in BIS and spectral entropy values during hypobaric hypoxia in volunteers. Methods: The study was conducted in a high-altitude chamber with 11 volunteers. After the subjects breathed 100% oxygen for 15 min at the ground level, the simulated altitude increased gradually to the 7620 m (25,000 ft) level while the subjects continued to breathe oxygen. Then, the subjects discontinued to breath oxygen and breathed room air at the 7620 m level for up to 5 min until they requested to stop hypoxic exposure. Oxygen saturation (SpO2), heart rate, 95% spectral edge frequency (SEF), BIS, response entropy (RE), and state entropy (SE) of spectral entropy were recorded throughout the study period. Results: Of the 11 subjects, seven subjects who underwent hypoxic exposure for 4 min were analysed. SpO2 decreased to 69% at the 7620 m level without oxygen. However, SEF, BIS, RE, and SE before and during hypoxic exposure were almost identical. Conclusion: These data suggest that hypoxia of oxygen saturation around 70% does not have a strong effect on BIS and spectral entropy. [source] Novel quinolone CHM-1 induces apoptosis and inhibits metastasis in a human osterogenic sarcoma cell lineJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 12 2009Shu-Chun Hsu Abstract Novel 2-phenyl-4-quinolone compounds have potent cytotoxic effects on different human cancer cell lines. In this study, we examined anticancer activity and mechanisms of 20-fluoro-6,7-methylenedioxy-2-phenyl-4-quinolone (CHM-1) in human osterogenic sarcoma U-2 OS cells. CHM-1-induced apoptosis was determined by flow cytometric analysis, DAPI staining, Comet assay, and caspase inhibitors. CHM-1-inhibited cell migration and invasion was assessed by a wound healing assay, gelatin zymography, and a Transwell assay. The mechanisms of CHM-1 effects on apoptosis and metastasis signaling pathways were studied using Western blotting and gene expression. CHM-1 induced G2/M arrest and apoptosis at an IC50 (3 µM) in U-2 OS cells and caspase-3, -8, and -9 were activated. Caspase inhibitors increased cell viability after exposure to CHM-1. CHM-1-induced apoptosis was associated with enhanced ROS generation, DNA damage, decreased ,,m levels, and promotion of mitochondrial cytochrome c release. CHM-1 stimulated mRNA expression of caspase-3, -8, and -9, AIF, and Endo G. In addition, CHM-1 inhibited cell metastasis at a low concentration (<3 µM). CHM-1 inhibited the cell metastasis through the inhibition of MMP-2, -7, and -9. CHM-1 also decreased the levels of MAPK signaling pathways before leading to the inhibition of MMPs. In summary, CHM-1 is a potent inducer of apoptosis, which plays a role in the anticancer activity of CHM-1. © 2009 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 27:1637,1644, 2009 [source] | ||||||||||