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Satisfactory Recoveries (satisfactory + recovery)
Selected AbstractsGC-MS analysis of organic compounds in wastewater and sewage sludgeJOURNAL OF SEPARATION SCIENCE, JSS, Issue 1 2008Axel Patrick Ligon Abstract A multimethod based on liquid,liquid extraction and solid,liquid extraction for the analysis of persistent organic pollutants in water and sludge from sewage treatment plants has been established. Traces of 22 organic compounds used in industry and personal care products (PCPs) were analyzed by GC/MS. The LODs for the analytes were less than 2.3 ng/L for wastewater and 31 ,g/kg (dry weight matter) for sewage sludge. Satisfactory recoveries (70,130%) were achieved. The validated method permits the analysis of water and sludge samples at various stages of the treatment from different sewage treatment plants. Thus, the distribution between water and sludge as well as the dissipation of the compounds analyzed were balanced. By this means, the efficiency of different wastewater treatment plants (WWTPs) can be evaluated and measures can be taken to optimize the treatment process at different stages. [source] Total obstetric brachial plexus palsy: Results and strategy of microsurgical reconstructionMICROSURGERY, Issue 3 2010Tarek A. El-gammal M.D. From 2000 to 2006, 35 infants with total obstetric brachial plexus palsy underwent brachial plexus exploration and reconstruction. The mean age at surgery was 10.8 months (range 3,60 months), and the median age was 8 months. All infants were followed for at least 2.5 years (range 2.5,7.3 years) with an average follow-up of 4.2 years. Assessment was performed using the Toronto Active Movement scale. Surgical procedures included neurolysis, neuroma excision and interposition nerve grafting and neurotization, using spinal accessory nerve, intercostals and contralateral C7 root. Satisfactory recovery was obtained in 37.1% of cases for shoulder abduction; 54.3% for shoulder external rotation; 75.1% for elbow flexion; 77.1% for elbow extension; 61.1% for finger flexion, 31.4% for wrist extension and 45.8% for fingers extension. Using the Raimondi score, 18 cases (53%) achieved a score of three or more (functional hand). The mean Raimondi score significantly improved postoperatively as compared to the preoperative mean: 2.73 versus 1, and showed negative significant correlation with age at surgery. In total, obstetrical brachial plexus palsy, early intervention is recommended. Intercostal neurotization is preferred for restoration of elbow flexion. Tendon transfer may be required to improve external rotation in selected cases. Apparently, intact C8 and T1 roots should be left alone if the patient has partial hand recovery, no Horner syndrome, and was operated early (3- or 4-months old). Apparently, intact nonfunctioning lower roots with no response to electrical stimulation, especially in the presence of Horner syndrome, should be neurotized with the best available intraplexal donor. © 2010 Wiley-Liss, Inc. Microsurgery, 2010. [source] Investigating the presence of pesticide transformation products in water by using liquid chromatography-mass spectrometry with different mass analyzers,JOURNAL OF MASS SPECTROMETRY (INCORP BIOLOGICAL MASS SPECTROMETRY), Issue 2 2008Félix Hernández Abstract Many pesticide transformation products (TPs) can reach environmental waters as a consequence of their normally having a higher polarity than their parent pesticides. This makes the development of analytical methodology for reliable identification and subsequent quantification at the sub-microgram per liter levels necessary, as required under current legislation. In this paper we report the photodegradation of several pesticides frequently detected in environmental waters from the Spanish Mediterranean region using the high-resolution and exact-mass capabilities of hybrid quadrupole time-of-flight mass spectrometry (QTOF MS) hyphenated to liquid chromatography (LC). Once the main photodegradation/hydrolysis products formed in aqueous media were identified, analytical methodology for their simultaneous quantification and reliable identification in real water samples was developed using on-line solid-phase extraction (SPE)-LC-tandem MS with a triple-quadrupole (QqQ) analyzer. The methodology was validated in both ground and surface water samples spiked at the limit of quantification (LOQ) and 10 × LOQ levels, i.e. 50 and 500 ng/l, obtaining satisfactory recoveries and precision for all compounds. Subsequent analysis of ground and surface water samples resulted in the detection of a number of TPs higher than parent pesticides. Additionally, several soil-interstitial water samples collected from the unsaturated zone were analyzed to explore the degradation/transformation of some pesticides in the field using experimental plots equipped with lisimeters. Several TPs were found in these samples, with most of them having also been detected in ground and surface water from the same area. This paper illustrates the extraordinary potential of LC-MS(/MS) with QTOF and QqQ analyzers for qualitative/structural and quantitative analysis, respectively, offering analytical chemists one of the most powerful tools available at present to investigate the presence of pesticide TPs in water. Copyright © 2007 John Wiley & Sons, Ltd. [source] Determination of amino acid neurotransmitters in human cerebrospinal fluid and saliva by capillary electrophoresis with laser-induced fluorescence detectionJOURNAL OF SEPARATION SCIENCE, JSS, Issue 16-17 2008Ying-Hua Deng Abstract A CE,LIF detection method has been developed to identify and quantitate six amino acid neurotransmitters including glutamic acid, aspartic acid, ,-aminobutyric acid, glycine, taurine, and glutamine. N -Hydroxysuccinimidyl fluorescein- O -acetate, a fluorescein-based dye, was employed for the derivatization of these neurotransmitters prior to CE,LIF analysis. Different parameters which influenced separation and derivatization were optimized in detail. Under optimum conditions, linearity was achieved within concentration ranges of up to three orders of magnitudes for those analytes with correlation coefficients from 0.9989 to 0.9998. The LODs ranged from 0.06 nM to 0.1 nM, and are thus superior or equivalent to those previously reported in the literature using CE,LIF detection. The proposed method has been successfully applied to the determination of amino acid neurotransmitters in biological samples such as human cerebrospinal fluid and saliva with satisfactory recoveries. [source] A reliable analytical approach based on gas chromatography coupled to triple quadrupole and time-of-flight mass analyzers for the determination and confirmation of polycyclic aromatic hydrocarbons in complex matrices from aquaculture activitiesRAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 13 2009Jaime Nácher-Mestre The potential of gas chromatography coupled to tandem mass spectrometry (GC/MS/MS) with a triple quadrupole analyzer (QqQ) has been investigated for the quantification and reliable identification of sixteen polycyclic aromatic hydrocarbons (PAHs) from the EPA priority list in animal and vegetable samples from aquaculture activities, whose fat content ranged from 5 to 100%. Matrices analyzed included fish fillet, fish feed, fish oil and linseed oil. Combining optimized saponification and solid-phase extraction led to high efficiency in the elimination of interfering compounds, mainly fat, from the extracts. The developed procedure minimized the presence of these interfering compounds in the extracts and provided satisfactory recoveries of PAHs. The excellent sensitivity and selectivity of GC/(QqQ)MS/MS in selected reaction monitoring (SRM) allowed to reach limits of detection at pg/g levels. Two SRM transitions were acquired for each analyte to ensure reliable identification of compounds detected in samples. Confirmation of positive findings was performed by GC coupled to high-resolution time-of-flight mass spectrometry (GC/TOFMS). The accurate mass information provided by GC/TOFMS in full acquisition mode together with its high mass resolution makes it a powerful analytical tool for the unequivocal confirmation of PAHs in the matrices tested. The method developed was applied to the analysis of real-world samples of each matrix studied with the result of detecting and confirming the majority of analytes at the µg/kg level by both QqQ and TOF mass spectrometers. Copyright © 2009 John Wiley & Sons, Ltd. [source] Differential Kinetic Spectrophotometric Determination of Methamidophos and Fenitrothion in Water and Food Samples by Use of ChemometricsCHINESE JOURNAL OF CHEMISTRY, Issue 3 2010Na Deng Abstract A spectrophotometric method for simultaneous analysis of methamidophos and fenitrothion was proposed by application of chemometrics to the spectral kinetic data, which was based upon the difference in the inhibitory effect of the two pesticides on acetylcholinesterase (AChE) and the use of 5,5,-dithiobis(2-nitrobenzoic acid) (DTNB) as a chromogenic reagent for the thiocholine iodide (TChI) released from the acetylthiocholine iodide (ATChI) substrate. The absorbance of the chromogenic product was measured at 412 nm. The different experimental conditions affecting the development and stability of the chromogenic product were carefully studied and optimized. Linear calibration graphs were obtained in the concentration range of 0.5,7.5 ng·mL,1 and 5,75 ng·mL,1 for methamidophos and fenitrothion, respectively. Synthetic mixtures of the two pesticides were analysed, and the data obtained processed by chemometrics, such as partial least square (PLS), principal component regression (PCR), back propagation-artificial neural network (BP-ANN), radial basis function-artificial neural network (RBF-ANN) and principal component-radial basis function-artificial neural network (PC-RBF-ANN). The results show that the RBF-ANN gives the lowest prediction errors of the five chemometric methods. Following the validation of the proposed method, it was applied to the determination of the pesticides in several commercial fruit and vegetable samples; and the standard addition method yielded satisfactory recoveries. [source] Sulfachlorpyrazine residues depletion in turkey edible tissuesJOURNAL OF VETERINARY PHARMACOLOGY & THERAPEUTICS, Issue 4 2010EBKOWSKA-WIERUSZEWSKA ,ebkowska-Wieruszewska, B.I., Kowalski, C.J. Sulfachlorpyrazine residues depletion in turkey edible tissues. J. vet. Pharmacol. Therap. doi: 10.1111/j.1365-2885.2009.01147.x. Sulfachlorpyrazine (SCP) is currently used to treat coccidian infections in turkeys; however, there is no information available about the withdrawal period necessary for the turkey to be safe for human consumption. A high performance liquid chromatography method with ultraviolet-visible light detection was adapted and validated for the determination of SCP in turkey tissues. The procedure is based on isolation of the (SCP sodium) compound from edible turkey tissues (muscles, liver, kidneys, and fat with skin) with satisfactory recovery (72.80 ± 1.40) and specificity. The residue depletion of SCP in turkeys was conducted after a dose of 50 mg/kg body weight/day had been administrated orally for 3 days. After treatment has been discontinued residue concentrations were detected in tissues on the 7th day. The highest SCP concentrations were measured in muscles. Based on the results presented in this study, it could be assumed that a withdrawal period of 21 days, before medicated turkeys could be slaughtered, would be sufficient to ensure consumer safety. [source] Ten-digit replantation with seven years follow-up: A case reportMICROSURGERY, Issue 5 2010Haibo Cong M.D. In this report, we present a case of successful replantation of 10-digit complete amputation and results of postoperative rehabilitation in 7 years follow-up. The rehabilitation program included psychotherapy, physical therapy, sensory re-education, and measurements. At the 7 years postoperatively, the static two-point discriminations of replanted digits ranged from 4 to 11 mm. Grasping powers ranged from 69 to 81 lb, and pinching powers ranged from 13 to 19 lb. The patient returned to the previous employment. Our experience has demonstrated that systemic postoperative rehabilitation and measurements could achieve satisfactory recovery of the sensory and motor functions of multiple-digit replantation. © 2010 Wiley-Liss, Inc. Microsurgery 30:405,409, 2010. [source] Acute Juvenile Pityriasis Rubra Pilaris: A Superantigen Mediated Disease?PEDIATRIC DERMATOLOGY, Issue 5 2001Isabel Betlloch M.D. Juvenile acute pityriasis rubra pilaris (JAPRP) is a form of pityriasis rubra pilaris (PRP) with particular clinical characteristics and course. It is usually preceded by an infectious condition. We report a boy, initially thought to have Kawasaki disease, and subsequently diagnosed as having JAPRP, who made a satisfactory recovery. In this case, prior antibiotic treatment made it impossible to show the presence of any microorganism. However, the clinical characteristics of these patients and the similarities with other disorders involving the skin that are mediated by superantigens led us to think that these antigens may be involved in the development of this disease. Also, in view of the obvious differences between JAPRP and the other PRP, we suggest that, in the future this disorder may be considered a separate entity as a reactive exanthem. [source] Liquid chromatographic,mass spectrometry analysis and pharmacokinetic studies of a novel rabeprazole formulation, sterile powder for injection, in dogs and ratsBIOPHARMACEUTICS AND DRUG DISPOSITION, Issue 4 2007Feng Shao Abstract Rabeprazole is among the most potent proton pump inhibitors (PPI) identified to date and it has been demonstrated that it is effective in such diseases as gastroesophageal reflux disease (GERD), duodenal ulcer and gastric ulcer. There is currently interest in developing a new formulation: rabeprazole sterile powder for injection (RSPI). This investigation was conducted to evaluate the preclinical pharmacokinetics of RSPI in rats and at the same time a comparative study was carried out in dogs between RSPI and Pariet® tablets using liquid chromatographic,mass spectrometry analysis. The liquid chromatographic,mass spectrometry method was first conducted and validated as being specific, and having accuracy, precision, sensitivity and a satisfactory recovery. After intravenous administration of RSPI (i.v.: 2, 6 and 18 mg/kg) to rats, no significant dose-dependency was found in the CL (4.20,5.72 l/h/kg), Varead (0.94,1.32 l/kg), dose-normalized AUC (197.20,245.82 µg/l*h based on 1 mg/kg) and t1/2 (p>0.05). In the dog, a randomized, open-label, crossover experiment was carried out to show that the mean area under the plasma concentration-time curve (AUC0,,) after i.v. administration of RSPI was at least four times larger than that following oral administration of Pariet® tablet at an equivalent dose but the elimination half-life of these two formulation was similar (p>0.05). The results showed that the pharmacokinetics of RSPI was linear (r2 = 0.98) in the dose range 2,18 mg/kg and the RSPI had a much higher AUC0,, and similar t1/2 values compared with the enteric-coated tablet. Copyright © 2007 John Wiley & Sons, Ltd. [source] | |||||||||||||