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Simultaneous Screening (simultaneous + screening)
Selected AbstractsSarcopenia is prevalent in patients with Crohn's disease in clinical remissionINFLAMMATORY BOWEL DISEASES, Issue 11 2008Stéphane M. Schneider MD Abstract Background: Patients with Crohn's disease (CD) are prone to osteoporosis. A loss of muscle mass, called sarcopenia, is responsible for an increased risk of disability. Many factors associated with osteopenia also decrease muscle mass. The aim of the present study was to measure the prevalence of sarcopenia in CD patients in remission and uncover its relationship with osteopenia. Methods: In all, 82 CD patients (43 female / 39 male; 36 ± 14 years; body mass index [BMI] 21.1 ± 3.4) and 50 healthy volunteers (30F/20M; 39 ± 13 years; BMI 22.2 ± 2.5) were studied. Body composition was assessed using dual-energy x-ray absorptiometry. Sarcopenia was defined as an appendicular skeletal muscle index (ASMI) below 5.45 kg/m2 for women and 7.26 for men. Osteopenia was defined as a T-score for bone mineral density (BMD) (g/cm2) below ,1.0. Results: In all, 60% of CD patients were found to be sarcopenic and 30% osteopenic, compared to 16% and 4% of controls, respectively (P < 0.01). ASMI was significantly lower in patients than in controls (6.0 ± 1.1 versus 6.5 ± 1.2; P < 0.05). Sarcopenic patients had significantly (P < 0.01) lower BMI (20.0 ± 3.5 versus 22.7 ± 2.8 kg/m2), lean mass (41.5 ± 9.1 versus 48.1 ± 9.1 kg), and BMD (1.09 ± 0.12 versus 1.15 ± 0.08 g/cm2) than nonsarcopenic patients; 91% of sarcopenic patients were also osteopenic. ASMI correlated with BMD (r = 0.46; P < 0.01) and BMI (r = 0.38; P < 0.01). Conclusions: The prevalence of sarcopenia is high in young CD patients and strongly related to osteopenia. These 2 phenomena may share similar mechanisms. Simultaneous screening for sarcopenia and osteopenia may be useful in CD patients. (Inflamm Bowel Dis 2008) [source] Analyses of gibberellins in coconut (Cocos nucifera L.) water by partial filling-micellar electrokinetic chromatography-mass spectrometry with reversal of electroosmotic flowELECTROPHORESIS, Issue 10 2008Liya Ge Abstract In this paper, we present the results of simultaneous screening of eight gibberellins (GAs) in coconut (Cocos nucifera L.) water by MEKC directly coupled to ESI-MS detection. During the development of MEKC-MS, partial filling (PF) was used to prevent the micelles from reaching the mass spectrometer as this is detrimental to the MS signal, and a cationic surfactant, cetyltrimethylammonium hydroxide, was added to the electrolyte to reverse the EOF. On the basis of the resolution of the neighboring peaks, different parameters (i.e., the pH and concentration of buffer, surfactant concentrations, length of the injected micellar plug, organic modifier, and applied separation voltage) were optimized to achieve a satisfactory PF-MEKC separation of eight GA standards. Under optimum conditions, a baseline separation of GA standards, including GA1, GA3, GA5, GA6, GA7, GA9, GA12, and GA13, was accomplished within 25,min. Satisfactory results were obtained in terms of precision (RSD of migration time below 0.9%), sensitivity (LODs in the range of 0.8,1.9,,M) and linearity (R2 between 0.981 and 0.997). MS/MS with multiple reaction monitoring (MRM) detection was carried out to obtain sufficient selectivity. PF-MEKC-MS/MS allowed the direct identification and confirmation of the GAs presented in coconut water (CW) sample after SPE, while, the quantitative analysis of GAs was performed by PF-MEKC-MS approach. GA1 and GA3 were successfully detected and quantified in CW. It is anticipated that the current PF-MEKC-MS method can be applicable to analyze GAs in a wide range of biological samples. [source] On-line solid-phase extraction with a monolithic weak cation-exchange column and simultaneous screening of ,1-adrenergic receptor antagonists in human plasmaJOURNAL OF SEPARATION SCIENCE, JSS, Issue 17 2007Xiaoyi Wei Abstract An on-line SPE,HPLC method, using a monolithic poly(glycidyl methacrylate-co-ethylene glycol dimethacrylate) (poly(GMA-EDMA)) based weak cation-exchange (WCX) column, was developed for simultaneous determination of ,1-adrenergic receptor antagonists in human plasma. The monolithic WCX column was prepared by an in-situ polymerization protocol and modified stepwise with ethylenediamine and chloroacetic acid. On connecting this column to an injection valve, an on-line SPE protocol could be established for removal of matrices (mainly proteins and lipids) and preconcentration of four ,1-adrenergic receptor antagonists in human plasma. This method was validated and then used for determination of terazosin, alfuzosin, prazosin, and doxazosin in clinical plasma samples. For all analytes, each calibration curve was found to be linear over a range of 0.005,5 ,g/mL (R >0.997), and the limit of detection for each analyte was 0.5 ng/mL. Recovery (> 80%) and precision (RSD <15%) for inter- and intra-day assay were tested at three concentration levels of each analyte and showed acceptable results for quantitative assay. Real samples from hypertensive patients were monitored and results were in agreement with those of the conventional liquid,liquid extraction-HPLC method. Furthermore, due to its good permeability and biocompatibility, the monolithic WCX sorbent could be reused more than 300 times. The proposed method was especially appropriate for multi-analyte monitoring in plasma samples. [source] A plate assay for simultaneous screening of polysaccharide- and protein-degrading micro-organismsLETTERS IN APPLIED MICROBIOLOGY, Issue 2 2005L.N. Ten Abstract Aims:, To develop a plate assay for simultaneous screening of polysaccharide-degrading and protein-degrading micro-organisms. Methods and Results:, A plate assay, based on the visible solubilization of small substrate particles and the formation of haloes on Petri dishes, containing a mixture of diversely coloured insoluble polysaccharides and dye-labelled collagen as chromogenic substrates, was developed. This method was successfully applied for isolating the diverse polysaccharide- and/or protein-degrading bacteria from soil and sludge samples. Selected strains were identified using 16S rDNA partial sequencing; most of them belong to the genera Bacillus, Cellulomonas and Cellulosimicrobium. Conclusions:, This novel approach provides unique and valuable information for direct primary screening when the target of selection is micro-organisms exhibiting protein-degrading activity, polysaccharide-degrading activity or a specific combination of them. Significance and Impact of the Study:, This plate assay is convenient and easy to perform, rapid, and more adaptable for screening of a large number of samples, compared with other existing methods in the literature. [source] Gas chromatographic,mass spectrometric urinary metabolome analysis to study mutations of inborn errors of metabolismMASS SPECTROMETRY REVIEWS, Issue 6 2005Tomiko Kuhara Abstract Urine contains numerous metabolites, and can provide evidence for the screening or molecular diagnosis of many inborn errors of metabolism (IEMs). The metabolomic analysis of urine by the combined use of urease pretreatment, stable-isotope dilution, and capillary gas chromatography/mass spectrometry offers reliable and quantitative data for the simultaneous screening or molecular diagnosis of more than 130 IEMs. Those IEMs include hyperammonemias and lactic acidemias, and the IEMs of amino acids, pyrimidines, purines, carbohydrates, and others including primary hyperoxalurias, hereditary fructose intolerance, propionic acidemia, and methylmalonic acidemia. Metabolite analysis is comprehensive for mutant genotypes. Enzyme dysfunction,either by the abnormal structure of an enzyme/apoenzyme, the reduced quantity of a normal enzyme/apoenzyme, or the lack of a coenzyme,is involved. Enzyme dysfunction,either by an abnormal regulatory gene, abnormal sub-cellular localization, or by abnormal post-transcriptional or post-translational modification,is included. Mutations,either known or unknown, common or uncommon,are involved. If the urine metabolome approach can accurately observe quantitative abnormality for hundreds of metabolites, reflecting 100 different disease-causing reactions in a body, then it is possible to simultaneously detect different mutant genotypes of far more than tens of thousands. © 2004 Wiley Periodicals, Inc., Mass Spec Rev 24:814,827, 2005 [source] | |||||||||||||