bluuebunny/crossref_metadata_2025_split huggingface dataset:
Determination of carbohydrates in juices by capillary electrophoresis, high‐performance liquid chromatography, and matrix‐assisted laser desorption/ionization‐time of flight‐mass spectrometry
Authors: Cabálková Jana , Žídková Jitka , Přibyla Lubomír , Chmelík Josef 
Published: January 2004

AbstractThe objective of this work was to develop a sample preparation procedure for determination of the carbohydrate profiles in commercial juice samples by three principally different analytical methods: capillary electrophoresis (CE) with indirect detection, high‐performance liquid chromatography (HPLC), and matrix‐assisted laser desorption/ionization‐time of flight‐mass spectrometry (MALDI‐TOF‐MS). The preparation and purification of juice samples prior to analysis is described. The method using Carrez reagents was found to be an efficient preparation tool for all three methods. The addition of Carrez reagents to the samples for mass analysis improved the quality of the mass spectra of oligosaccharides. The amounts of glucose, fructose, and sucrose as major carbohydrates in fruit juices measured by CE using a simple instrument are in good agreement with the HPLC values and the data declared by the producers of the juices. The results from both methods are critically evaluated and their impact for studies of authenticity is discussed. The decrease of sucrose amount during the storage of samples was explained by acid hydrolysis of this disaccharide.
Effect of matrix chain length on the electrophoretic mobility of large linear and branched DNA in polymer solutions
Authors: Saha Sourav , Heuer Daniel M. , Archer Lynden A. 
Published: January 2004

AbstractWe study the effect of matrix chain molecular weight Mw and concentration c on the electrophoretic mobility μ of large linear and star‐like, branched DNA in polymer solutions. Polyethylene oxide (PEO) with narrow molecular weight distributions form the main focus of this study. For PEO concentrations ranging from one half the overlap concentration, c*, to 3c*, the effective drag coefficient, ζ $\equiv {{\mu _0 } \over \mu } - 1$, satisfies the following approximate scaling relationship, ζ $\sim cM_w^{0.7}$ . Here, μ0 is the electrophoretic mobility in free solution. While the concentration dependence is consistent with predictions from the transient entanglement coupling (TEC) model, the molecular weight dependence is significantly weaker. Although a similar dependence of mobility on Mw can be predicted when nonentangling collisions are the dominant source of drag, a model based on these collisions alone cannot reproduce the experimental observations. We also find that the architecture of large DNA does not affect either the concentration dependence or molecular weight dependence of the electrophoretic mobility.
Two‐dimensional protein database of human pancreas
Authors: Hu Liping , Evers Stefan , Lu Zhao Hui , Shen Yan , Chen Jie 
Published: January 2004

AbstractWe report here the two‐dimensional protein database of human pancreas. The proteins were analyzed by two‐dimensional electrophoresis followed by matrix‐assisted laser desorption/ionization‐time of flight‐mass spectrometry (MALDI‐TOF‐MS). Totally, 302 proteins were identified, of which about 27% were enzymes with a broad range of catalytic activities. Several of these are specifically expressed in pancreas, such as pancreatic amylase, pancreatic stone protein, pancreatitis‐associated protein, pancreatic lipase, pancreatic elastase, etc. Structural and cytoskeletal proteins are also strongly represented on the gels. Thus, the pancreatic proteome reflects the organ's function. This work paves the way for further studies on pancreatic protein expression in health and disease, such as diabetes and pancreatic cancer.
Sodium dodecyl sulfate‐capillary gel electrophoresis of polyethylene glycolylated interferon alpha
Authors: Na Dong H. , Park Eun J. , Youn Yu S. , Moon Byung W. , Jo Yeong W. , Lee Sung H. , Kim Won‐Bae , Sohn Yeowon , Lee Kang C. 
Published: January 2004

AbstractSodium dodecyl sulfate‐capillary gel electrophoresis (SDS‐CGE) using a hydrophilic replaceable polymer network matrix was applied to characterize the polyethylene glycol(PEG)ylated interferon alpha (PEG‐IFN). The SDS‐CGE method resulted in a clearer resolution in both the PEG‐IFN species and the native IFN species. The distribution profile of PEGylation determined by SDS‐CGE was consistent with that obtained by SDS‐polyacrylamide gel electrophoresis (PAGE) with Coomassie blue or barium iodide staining. The result was also compared using matrix‐assisted laser desorption/ionization‐time of flight‐mass spectrometry. SDS‐CGE was also useful for monitoring the PEGylation reaction to optimize the reaction conditions, such as reaction molar ratio. This study shows the potential of SDS‐CGE as a new method for characterizing the PEGylated proteins with advantages of speed, minimal sample consumption and high resolution.
Development and validation method for determination of Paroxetine and its metabolites by nonaqueous capillary electrophoresis in human urine. Experimental design for evaluating the ruggedness of the method
Authors: Rodríguez Flores Juana , Barzas Nevado Juan J. , Contento Salcedo Ana M. , Cabello Díaz Maria P. 
Published: January 2004

AbstractA simple, rapid, and sensitive procedure using nonaqueous capillary electrophoresis (NACE) to measure Paroxetine (one of the mostly used antidepressants for mental diseases treatment) and three metabolites has been developed and validated. Optimum separation of paroxetine and metabolites was obtained on a 57 cm×75 μm capillary using a nonaqueous buffer system of 9:1 methanol‐acetonitrile containing 25 mM ammonium acetate and 1% acetic acid, with temperature and voltage of 25°C and 15 kV, respectively, and hydrodynamic injection. Fluoxetine was used as an internal standard. Good results were obtained for different aspects including stability of the solutions, linearity, accuracy, and precision. Detection limits between 9.3 and 23.1 μg·L−1 were obtained for paroxetine and its metabolites. A ruggedness test of the method was carried out using the Plackett‐Burman fractional factorial model with a matrix of 15 experiments. This method has been used to determine paroxetine and its main metabolite B at clinically relevant levels in human urine. Prior to NACE determination, the samples were purified and enriched by means of an extraction‐preconcentration step with a preconditioned C18 cartridge and eluting the compounds with methanol.
Creatinine determination in serum by capillary electrophoresis
Authors: Paroni Rita , Fermo Isabella , Cighetti Giuliana , Ferrero Carlo Alberto , Carobene Anna , Ceriotti Ferruccio 
Published: January 2004

AbstractCreatinine in human serum was separated in a fused‐silica capillary with H3PO4 (75 mmol/L, pH 2.5) as BGE, followed by UV detection at 200 nm. Serum with methylimidazole added as internal standard was deproteinized with acetonitrile and the supernatant, after dilution with water was injected at pressure mode. Creatinine and methylimidazole were baseline‐resolved in 6.5 min. Linearity in the 0–880 μmol/L range gave an r2 ≥ 0.998, recovery was 102 ± 2.8% (n = 6). Enzymatic breakdown with creatininase confirmed that serum does not interfere. The within‐day and between‐days coefficient of variation (CV) were ≤ 2.16 and 2.7%, respectively. The accuracy, determined for lyophilized samples by isotope dilution gas chromatography‐mass spectrometry was ≤ ± 2.0%. The results were compared with HPLC for 32 lyophilized samples and on 27 serum pools. Capillary electrophoresis, rapid and inexpensive, seems a promising alternative to high‐performance liquid chromatography (HPLC) for creatinine determination in human serum.
Capillary zone electrophoresis for determination of carbohydrate‐deficient transferrin in human serum
Authors: Fermo Isabella , Germagnoli Luca , Soldarini Armando , Dorigatti Fernanda , Paroni Rita 
Published: January 2004

AbstractCarbohydrate‐deficient transferrin (CDT) is the most specific marker for diagnosis of chronic excessive alcohol consumption and includes the serum transferrin (Tf) isoforms with two or less sialic acid residues (di‐, mono‐, and asialo‐Tf). To monitor serum CDT, we developed a capillary zone electrophoresis (CZE) method based on the dynamic capillary coating with diethylenetriamine (DETA). The separation was performed in a bare fused‐silica capillary (50 μm ID, 57 cm in length), applying a voltage of 25 kV and a temperature of 40°C. Using a 100 mmol/L borate buffer, pH 8.4 with 3 mmol/L DETA, the Tf isoforms (asialo‐ to pentasialo‐Tf) were resolved within 16 min. Enzymatic cleavage of sialic acid residues with neuraminidase and immunosubtraction were used to identify CDT isoforms. The relative amount of CDT expressed as area % of disialo‐Tf isoform related to the area of tetrasialo‐Tf in 50 healthy donors (24 males and 26 females; aged 25–50 years) was 3.15 ± 0.76% (mean ± SD). The comparison between CDT values obtained by this CZE procedure and the “Axis‐Shield %CDT” kit gave r = 0.644, p < 0.001 (n = 290). This easy to use and inexpensive CZE procedure could be an ideal tool to investigate CDT proteins for clinical or forensic purposes.
Development of a fully buffered molybdate electrolyte for capillary electrophoresis with indirect detection and its use for analysis of anions in Bayer liquor
Authors: Chovancek Milan , Choo Peter , Macka Miroslav 
Published: January 2004

AbstractA new counterion‐buffered molybdate electrolyte was developed and optimized for simultaneous quantitative determination of up to eight anions (chloride, sulphate, oxalate, fluoride, formate, malonate, succinate, and acetate) in Bayer liquor by capillary electrophoresis with indirect detection at 214 nm. The separation parameters were optimized in respect to separation of the critical analyte group fluoride – formate – malonate, with the optimal electrolyte prepared from molybdic trioxide containing 5.0 mmol/L MoO3, 1.3 mmol/L cetyltrimethylammonium bromide (CTAB), and buffered with diethanolamine (DEA) to pH 9.2 (ca. 20 mM DEA). Total length of separation capillary was 80 cm, resulting in run time of under 4 min. The method is suitable for a wide concentration range of the analytes (1–50 mg/L) with linear calibration plots (R2 = 0.9983–0.9999). Relative standard deviations were 0.05%–0.07% for migration times and 0.67%–2.04% for peak areas. The detection limits were in the range of 0.17–0.51 mg/L or 2–10 μmol/L (hydrostatic injection of 30 s of 1000× diluted sample). Due to its good buffering capacity, the electrolyte exhibited an excellent ruggedness and good tolerance to the alkaline samples. Consequently, Bayer liquor samples could be diluted as little as 100× which allows more sensitive determination of minor components over previous methods. The method was successfully applied to analysis of Bayer liquor samples with recoveries in the range of 95–105%.
Enantioseparation of new nucleoside analogs, related to d4T and acyclovir, by chiral capillary electrophoresis using highly sulfated β‐cyclodextrins
Authors: Lipka Emmanuelle , Daniel Cecile , Vaccher Marie‐Pierre , Glaçon Virginie , Ewing David , Mackenzie Graham , Len Christophe , Bonte Jean‐Paul , Vaccher Claude 
Published: January 2004

AbstractBaseline separation of some new acyclic nucleosides which are potential antiviral agents was achieved using cyclodextrin capillary zone electrophoresis (CD‐CZE). A method for the enantiomeric resolution of these compounds and determination of their enantiomeric purity was developed using anionic CDs (highly sulfated‐CD or highly S‐CD) as chiral selectors and capillaries, which were dynamically coated with polyethylene oxide (PEO). Operational parameters including (i) the nature and concentration of the chiral selectors, (ii) organic modifiers, (iii) temperature, and (iv) applied voltage were investigated. The use of charged CDs provides (i) a supplementary driving force for the compounds in a running buffer and (ii) enantiomeric resolution by inclusion of compounds in the CD cavity. The highly S‐CD was found to be the most effective complexing agent and allowed good enantiomeric resolution. The complete resolution of five nucleoside analogs was obtained using 25 mM phosphate buffer, pH 2.5, containing either highly S‐α‐CD, S‐β‐CD or S‐γ‐CD at 30°C with an applied field of 0.30 kV/cm. The apparent association constants of the inclusion complexes were calculated. The enantiomer migration order for the molecules investigated was determined and the detection limit of enantiomeric impurities was found to vary between 0.34 to 3.56 ng·mL−1 for the first enantiomer.
Application of capillary electrophoresis with different sample stacking strategies for the determination of a group of nonsteroidal anti‐inflammatory drugs in the low μg ∵ L−1 concentration range
Authors: Macià Alba , Borrull Francesc , Aguilar Carme , Calull Marta 
Published: January 2004

AbstractSeveral on‐column sample preconcentration modes – large‐volume sample stacking using the EOF pump (LVSEP), LVSEP with anion‐selective exhaustive injection (LVSEP‐ASEI) and field‐amplified sample injection with sample matrix removal using the electroosmotic flow (EOF) pump (FAEP) – were used to analyze some nonsteroidal anti‐inflammatory drugs (NSAIDs) by capillary electrophoresis, and then compared. Methanol was the background electrolyte solvent to suppress the EOF. The effect of the type and length of the solvent plug, and the sample injection time were investigated in FAEP to determine the conditions that provided the best response. LVSEP, LVSEP‐ASEI, and FAEP improved the sensitivity of the peak area by 100‐, 1200‐, and 1800‐fold, respectively. The methodology developed, in combination with solid‐phase extraction (SPE), was applied to the analysis of water samples.
Explorative data analysis of two‐dimensional electrophoresis gels
Authors: Schultz Jakob , Gottlieb David Mark , Petersen Marianne , Nesic Ljiljana , Jacobsen Susanne , Søndergaard Ib 
Published: January 2004

AbstractMethods for classification of two‐dimensional (2‐DE) electrophoresis gels based on multivariate data analysis are demonstrated. Two‐dimensional gels of ten wheat varieties are analyzed and it is demonstrated how to classify the wheat varieties in two qualities and a method for initial screening of gels is presented. First, an approach is demonstrated in which no prior knowledge of the separated proteins is used. Alignment of the gels followed by a simple transformation of data makes it possible to analyze the gels in an automated explorative manner by principal component analysis, to determine if the gels should be further analyzed. A more detailed approach is done by analyzing spot volume lists by principal components analysis and partial least square regression. The use of spot volume data offers a mean to investigate the spot pattern and link the classified protein patterns to distinct spots on the gels for further investigation. The explorative approach in analysis of 2‐D gels makes it possible, in a fast and convenient way, to screen many gels in order to determine the protein patterns that form clusters and could be selected for further examination.
Verrucous carcinoma of the paranasal sinuses: Case report and clinical update
Authors: Paleri Vinidh , Orvidas Laura J. , Wight Richard G. , Bradley Patrick J. 
Published: January 2004

AbstractBackground.Verrucous carcinoma is a low‐grade malignancy that has been reported to occur in all anatomic sites of the head and neck. Fourteen cases of verrucous carcinoma of paranasal sinus origin have been reported to date in the English literature.Methods.Case report and retrospective review of all cases of verrucous carcinoma of the paranasal sinuses in the English literature. All authors were contacted to provide missing data and long‐term follow‐up.Results.Five of the eight authors contacted responded, and the most current data from all 15 cases was compiled. Eleven of the 15 patients (73%) were men and ranged in age from 35 to 81 years (median, 68 years). The maxillary sinus is the most common paranasal sinus involved (93%). Presentation often occurred late, with 12 of 15 (80%) initially being seen at stage T3 or higher. Surgical excision was the treatment of choice, and median disease‐free survival was 54 months.Conclusions.Verrucous carcinoma of the paranasal sinuses is a rare but potentially curable disease. Treatment is surgical, and prognosis is good with early intervention. © 2003 Wiley Periodicals, Inc. Head Neck 26: 184–189, 2004
Parapharyngeal lymph node metastasis: An unusual presentation of papillary thyroid carcinoma
Authors: Lombardi Davide , Nicolai Piero , Antonelli Antonino R. , Maroldi Roberto , Farina Davide , Shaha Ashok R. 
Published: January 2004

AbstractBackground.Parapharyngeal space nodal metastases are usually secondary to malignancies of the pharynx and sinonasal tract, although localization of lymphomas is also possible. Parapharyngeal metastases arising from thyroid papillary carcinoma are instead an exceedingly rare event, with only 10 cases reported up to now in the literature.Methods.We describe two cases of parapharyngeal metastasis from thyroid papillary carcinoma in a man and a woman, aged 40 and 52 years, respectively.Results.Both patients had a lesion that clinically appeared to be located in the parapharyngeal space; they underwent CT and MRI, which detected a cystic mass in the poststyloid compartment. In the first patient, fine‐needle aspiration cytology failed in identifying the histologic nature of the lesion, which was excised through a transcervical approach. A diagnosis of metastatic thyroid papillary carcinoma was rendered and therefore the patient underwent total thyroidectomy. In the second patient, a total thyroidectomy, previously scheduled for multinodular goiter, was performed along with the removal of the parapharyngeal mass. Definitive histologic findings revealed that the two parapharyngeal masses were cystic metastases from a thyroid papillary carcinoma. Both patients received postoperative 131I treatment. Twenty‐four months after surgery, the first patient is free of disease, whereas the second one has clear signs of abnormal 131I uptake in the lungs.Conclusions.The differential diagnosis of a parapharyngeal poststyloid mass should also include metastasis from thyroid papillary carcinoma. When the lesion displays a cystic appearance on imaging, it is advisable to rule out a thyroid primary by ultrasonographic examination. The occurrence of a metastasis in such unusual site, even though rarely reported, does not seem to significantly affect the prognosis of the disease. © 2003 Wiley Periodicals, Inc. Head Neck 26: 190–196, 2004
Tailored endoscopic surgery for the treatment of sinonasal inverted papilloma
Authors: Lee Ta‐Jen , Huang Shiang‐Fu , Huang Chi‐Che 
Published: January 2004

AbstractBackground.This retrospective study was designed to evaluate the efficacy of tailored endoscopic surgery. Tailored endoscopic surgery aims at resecting the inverted papilloma completely with a customized surgical approach, especially when an en‐bloc excision cannot be comprehensively or routinely achieved because of the immense extent of the tumor.Methods.Between November 1991 and March 2002, 43 patients with sinonasal inverted papillomas were treated by tailored endoscopic surgery. The average duration of follow‐up for this population was 25.3 months (range, 9–150 months). A staging system developed by Krouse was adopted for tumor grading. On the basis of tailored endoscopic surgery, 15 localized lesions and 12 smaller extensive lesions (Krouse stages 1 and 2) were treated by ordinary endoscopic resection, whereas 16 larger extensive lesions (Krouse stages 3 and 4) in which the tumors were immense were subjected to sequential segmental endoscopic surgery (SSES). Seven of these 16 larger extensive lesions combined with endoscopic medial maxillectomy because of extensive encroachment of maxillary sinus antrum.Results.Four patients (9.3%) had residual disease, each requiring one revision surgery. All tumors were successfully resected. No patient required lateral rhinotomy or midfacial degloving procedure. No major complications were encountered in any of the patients. None of the patients had residual disease at the time of this writing.Conclusions.Tailored endoscopic surgery is a safe and effective treatment that obviates the need for more extensive surgery for the management of inverted papilloma. Proper preoperative evaluations, intraoperative determination of extent and attachment of the tumor, close endoscopic follow‐up, and expert application of endoscopic techniques are the keys to the successful use of tailored endoscopic surgery. © 2004 Wiley Periodicals, Inc. Head Neck 26: 145–153, 2004
Prognostic factors in sinonasal tumors involving the anterior skull base
Authors: Suarez Carlos , Llorente Jose L. , Fernandez De Leon Ramon , Maseda Eduardo , Lopez Aurora 
Published: January 2004

AbstractBackground.Anterior craniofacial resection is a standardized procedure for the treatment of ethmoid and frontal orbital tumors with intracranial invasion.Methods.A retrospective review of 100 patients with sinonasal tumors involving the anterior skull base who underwent combined craniofacial surgery at the Hospital Central de Asturias.Results.The most frequent pathologic entity was adenocarcinoma (53 cases) and other epithelial tumors (29 cases). Five‐year actuarial survival according to the Kaplan–Meier method was 40%. Factors such as involvement of surgical margins, orbital periosteum involvement, frontal sinus invasion, or spread into the dura had no significant effect on survival. Survival, however, was affected by the histologic findings of the tumor (p = .03), brain involvement (p = .04), deep soft tissue involvement of the orbit (p = .003), involvement of the sphenoid sinus (p = .001), previous treatment (p = .05), and postoperative recurrence (p = .0000). Neither the INT staging system nor the UICC system showed statistical prognostic significance. After multivariate analysis and Cox regression analysis, only recurrence after craniofacial resection, involvement of soft tissues of the orbit, and invasion of the sphenoid sinus significantly influenced survival.Conclusions.Standard staging systems did not show statistical prognostic significance. Only involvement of some critical areas was reliable as predictor of an unfavorable outcome. © 2003 Wiley Periodicals, Inc. Head Neck 26: 136–144, 2004