bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of flavonoid extracts from grapefruit seeds and peel flour on soybean oil stability
Authors: Moreno Álvarez Mario José , Guarán Carmen Ysabel , Belén Camacho Douglas Rafael , García-Pantaleón David , Medina Martínez Carlos Alberto
Published: October 2008

The antioxidant activity of the aqueous extracts from grapefruit seed and peel was evaluated. The seeds and peels were transformed into flour and the flavonoids were extracted by means of organic solvents in the following flour/solvent ratios: 05:25; 1:25 and 2:25. Then, single extractions with 25mL of methanol 85% (v/v) were produced. Afterward, methanolic extracts were mixed in proportion 1:1 (v/v) with petroleum ether and stirred until the appearance of two sharp phases. Subsequently, the aqueous phase was extracted with ethyl acetate and two phases were separated. Doses of every phase in proportion of 0.01%, 0.75% and 0.10%, were added to soybean oil. Samples were stored in an air stove at 60°C ± 1°C and the peroxide value was determined every 24 h for the 600h of study. Significant differences were found between treatments (P< 0.05). An antioxidant effect was shown independently of the metabolite source, flour weight/extraction volume ratio or extract concentration (P < 0.05). The major antioxidant effect showed by the treatments were with 0.01% aqueous extract from 0.5:25 seed flour/solvent ratio, and 0.75% aqueous extract from 0.5:25 peel flour/solvent ratio. No treatment showed pro-oxidant effects. In conclusion, the incorporation of flavonoid extracts into deodorized soybean oil permitted the confirmation of its antioxidant performance.
The biodegradation of Olive Oil Mill Wastewaters by Sawdust and by a Phanerochaetae chrysosporium
Authors: Mebirouk M. , Sbai L. , Lopez M. , Gonzalez J.
Published: October 2008

This paper discusses decolorization and chemical oxygen demand (COD) abatement in olive mill wastewaters (OMW) by Phanerochaetae chrysosporium grown in static, stirred and immobilized cultures. When P. Chrysosporium is used in cultures, no decolorization of crude OMW is observed. Decolorization occurs only after the removal of polyphenols by adsorption in sawdust, which allows a 39% polyphenol removal. The use of a High lignin peroxides (Lip) producing medium, yields the highest OMW decolorization and COD removal efficiencies. The use of P. Chrysosporium immobilized on polyurethane foam leads to significant abatements of OMW polluting characteristics. And COD abatement reached 70%. The reduction of polyphenols reached its highest level at 62%. A significant effluent decolorization is apparent.
Assessment of oxidative deterioration of soybean oil at ambient and sunlight storage
Authors: Anwar Farooq , Shahid Chatha Shahzad Ali , Ijaz Hussain Abdullah
Published: October 2008

This study was carried out in order to probe the extent of oxidative alterations in soybean oil (SBO), subjected to ambient and sunlight storage, over a period of 180 days. The magnitude of oxidative changes was monitored by the periodical measurement of peroxide value (PV), color, free fatty acid (FFA) contents, refractive index (RI), p-anisidine-, conjugated dienes-, conjugated trienes-, and iodine- values. At the end of storage period (180 days), the initial contents of FFA (0.02 % as oleic acid) and PV (0.02 meq/kg of oil) of the SBO samples subjected to ambient and sunlight storage reached the level of 1.77, 2.90 % and 20.52, 41.89 meq/kg of oil, respectively. The initial values of RI (40°C) (1.4630), panisidine (1.10), conjugated dienes (0.08) and conjugated trienes (0.04) rose to the point of 1.4647, 1.4659; 36.13, 50.40; 23.97, 41.49 and 13.81, 19.35, respectively. Whereas, the iodine value (g of I /100 g of oil) decreased from 138.00 to 126.18 and 118.04, respectively. At the end of storage period, the overall order, indicative of the oxidative changes in RI, FFA, IV, color (red + yellow), PV, P-anisidine, conjugated dienes and conjugated trienes of the SBO subjected to ambient and sunlight storage was as follows: 1.001:1.002, 1.00:1.65, 0.91:0.86, 0.80:0.60 + 0.75:0.50, 1.00:2.04, 1.00:1.39, 1.00:1.73 and 1.00:1.40, respectively. The results of various parameters investigated in the present study demonstrated the magnitude of oxidative deterioration of the SBO samples exposed to sunlight to be significantly (P < 0.05) pronounced as compared with that of ambient.
Proximate composition of Turkish sesame seeds and characterization of their oils
Authors: Kemal Ünal M. , Yalçın Hasan
Published: October 2008

A proximate composition of four varieties of Turkish sesame seeds (moisture, ash, protein, oil) was determined along with a characterization of their oils (fatty acids, triacylglycerols and desmethylsterols) The results of the proximate analysis showed the following contents: moisture, 4,40%; ash, 4,41%; protein, 21,00%; and oil, 54,26%. Oleic and linoleic acids were the major unsaturated fatty acids while palmitic and stearic were the main saturated. The triacylglycerol composition of the sesame oil samples was determined by HPLC and LOL; LOO; PLO; LLL; OOO were the major triglycerides while triacylglycerols containing oleic and linoleic acyl residues comprize 62,45% of the total. The major desmethyl sterols found in sesame seed oils were β-sitosterol, campasterol, stigma-sterol, and Δ-5, avenasterol. Small proportions of cholesterol, clerosterol 5,24 stigmastedienol, Δ-7, stigmastenol and avenasterol were also identified.
Quantitative and qualitative variation of the fatty acid composition in the dinoflagellate Crypthecodinium cohnii under nitrogen starvation conditions
Authors: Mendoza H. , Molina Cedres C. , De la Jara A. , Nordström L. , Freijanes K. , Carmona L.
Published: October 2008

Crypthecodinium cohnii is a heterotrophic dinoflagellate that can achieve a lipid content greater than 20% on dry weight. DHA can represent up to 40% of the total fatty acids. Our objective was to investigate the variation in fatty acid content when growth conditions are optimal compared with when there is limited growth, due to the absence of nitrogen in the media. Nitrogen-limited growth conditions caused the cells to stop dividing and accumulate lipids, principally as docohexanoic acid (DHA). Oxygen availability in the culture favoured DHA accumulation. In the cultures without nitrogen and with oxygen availability there was a lipid cell content 3,18 times higher than in the control condition (with nitrogen and air), and 2,25 higher than those without nitrogen and air. C. cohnii can be used as an optimal DHA source for the production of phytodiets in aquaculture.
Extra virgin olive oil from Somontano: Evaluation of physico-chemical changes after domestic frying of frozen prefried potatoes
Authors: Sánchez-Gimeno A. C. , Benito M. , Vercet A. , Oria R.
Published: October 2008

The behavior of Somontano extra virgin olive oil (obtained from Empeltre and Arbequina olive varieties) in the domestic deep frying of prefried frozen potatoes was studied by submitting the olive oil to successive frying cycles. After different frying cycles physico-chemical modifications were monitored through the determination of several chemical (iodine value, total phenols content) and physical parameters (viscosity and ultraviolet spectra). An increase in viscosity and a decrease in iodine value, total phenol content and an increase in absorbance at 235, 269 y 280 nm were observed. In general, Somontano olive oil was revealed appropriate for domestic frying because of the high number of frying cycles permitted before reaching the polar compound limit established by Spanish legislation.
Quality assessment of Moringa concanensis seed oil extracted through solvent and aqueous-enzymatic techniques
Authors: Latif Sajid , Anwar Farooq
Published: October 2008

The composition and quality of the M. concanensis seed oil extracted through an aqueous-enzyme-assisted technique, using three commercial enzyme-mixtures (Natuzyme, Kemzyme, and Feedzyme) was compared to those of the control-, (without enzymes) and solvent-extracted oils. Aqueous enzyme-extracted M.concanensis seed oil content ranged from 23.54 to 27.46% and was significantly (P < 0.05) higher than that of the control (15.41%). Analyses of the oilseed residues (meals) revealed no significant (P > 0.05) variation in the contents of fiber and ash within the three extraction methods. However, the protein content of the meal obtained through the aqueous-enzyme and control methods was significantly (P < 0.05) lower as compared to that of the solvent-extracted. There were no significant (P < 0.05) differences in iodine value (67.1-68.0 g of iodine/100 g of oil), density at 24 oC (0.865-0.866 g mL_1), refractive index at 40 ºC (1.4622-1.4627) and unsaponifibale (0.69-0.76%) matter of the M. concanensis seed oils extracted using the three methods. The specific extinctions at 232 and 270 nm, peroxide value, p-anisidine, free fatty acid contents and color values of the aqueous-enzyme-extracted oil were found to be lower than that of solvent-extracted oil and thus revealed good quality. The oils extracted through the three methods exhibited no significant (P < 0.05) variation in their contents of major fatty acids except stearic (18:0) and linoleic (18:2) acids. The level of γ-tocopherol in enzymeextracted oil, even though comparable to the control, was significantly (P_0.05) higher than that of solvent-extracted oil. The content of α-tocopherol in the enzyme-extracted oil was found to be higher than that of the control but lower than that of solvent- extracted oil.
Quality evaluation of Pecan nuts [Carya illinoinensis (Wangenh.) C. Koch] during storage in different packaging
Authors: Oro Tatiana , Ogliari Paulo José , Dias de Mello Castanho Amboni Renata , Barrera-Arellano Daniel , Block Jana Mara
Published: October 2008

In the present work, the quality changes of pecan nuts stored in nylon-polyethylene plastic film under vacuum and in polypropylene plastic recipients at ambient temperature for 150 days were evaluated. The nutritional composition, fatty acid composition and tocopherol content of the pecan nuts reveal interesting nutritional characteristics and an oil with high contents of mono-unsaturated fatty acids and γ-tocopherol. During storage, moisture content did not suffer significant changes, but a gradual and significant darkening of the surface of the nuts occurred. The changes in acid value, peroxide value and specific extinction of the extracted oil were significant. The microbiological quality was excellent and the presence of Salmonella sp. was not detected. Through sensory analysis, the shelf-life of the product was determined as 120 days, without significant differences between the two types of packaging used.
Solvent-free lipase-catalyzed preparation of diglycerides from co-products of vegetable oil refining
Authors: Tangkam Kamol , Weber Nikolaus , Wiege Berthold
Published: October 2008

Co-products of vegetable oil refining such as a mixed deodorizer distillate resulting from the refining of various vegetable oils, a crude distillate resulting from the physical refining of coconut oil and commercial mixtures of distilled sunflower and coconut fatty acids were used as starting materials for the enzymatic preparation of diglycerides. Reaction conditions (temperature, pressure, molar ratio) for the formation of diglycerides by lipase-catalyzed esterification/transesterification were studied using the mixed deodorizer distillate and glycerol as starting materials. The best results were obtained with the immobilized lipase B from Candida antarctica (Novozym 435) in vacuo at 60 °C leading to moderate proportions (~52%) of diglycerides. The proportion of diglycerides increased when residual acylglycerides of the co-products of vegetable oil refining were hydrolyzed prior to esterification. Thus, the esterification of hydrolyzed co-products of vegetable oil refining with glycerol led to high formation (62-72%) of diglycerides. Short-path vacuum distillation of the esterification products yielded distillation residues containing from 70% to 94% diglycerides. The proportions of fatty acids and monoglycerides in the distilled residues were quite low (≤ 1% and 1 to 3.9%, respectively). Immobilized lipases from Rhizomucor miehei and Thermomyces lanuginosus were less active as esterification biocatalysts.
Influence of brine concentration on sugar and sodium chloride diffusion during the processing of the green olive variety Arauco
Authors: Maldonado M. B. , Zuritz C. A. , Miras N.
Published: October 2008

The green olive variety Arauco were debittered using lye concentrations of, 2.50% NaOH.They were then subjected to two rinsing processes with tap water. Next, the olives were cured with brines at 7%, 10% and 13% sodium chloride concentration. During this curing process, the loss of reducing sugars from the olives, and the diffusion of sodium chloride into the olives were quantified. Effective diffusion coefficients of both solutes in the skin and the flesh were calculated for this period using a diffusion model for a composite hollow sphere. The skin effective diffusion coefficients for both solutes ranged from entre 8,27x10-14- m2/s to 4,04x10-13 m2/s. The flesh coefficients varied from 2,92x10-9 m2/s to 3,99x10-9 m2/s for sodium chloride and from 9,76x10-11 m2/s to 2,22x10-10 m2/s for reducing sugars.
Synthesis of cocoa butter triacylglycerols using a model acidolysis system
Authors: Çiftçi Ozan Nazim , Fadiloǧlu Sibel , Kowalski Boleslaw , Göǧüş Fahrettin
Published: October 2008

The effects of reaction parameters such as substrate mole ratio, reaction temperature, enzyme load, water content and reaction time were studied in a model enzymatic acidolysis system. Palmitic and stearic acids were incorporated into triolein (OOO) under the catalysis of sn-1,3 specific lipase to produce the three major triacylglycerols (TAGs) in cocoa butter (CB), namely, 1,3-dipalmitoyl-2-oleoyl--glycerol (POP), 1(3)-palmitoyl-3(1)-stearoyl-2-oleoyl-glycerol (POS) and 1,3distearoyl-2-oleoyl-glycerol (SOS). TAG contents of the reaction products were analyzed by High Performance Liquid Chromatograph (HPLC).The best results (15.2% POP, 30.4% POS, 15.2 % SOS) were obtained at 1:3:3 (OOO:palmitic acid:stearic acid) substrate mole ratio and reaction parameters: time 10 h, temperature 45 oC, enzyme load 20 %, water content 5 %. The results obtained in this model system might be used for the optimization and application of lipase catalyzed acidolysis reactions in natural systems to produce cocoa butter equivalents (CBEs).
Prediction of a model enzymatic acidolysis system using neural networks
Authors: Çiftçi Ozan Nazım , Fadıloǧlu Sibel , Göǧüş Fahrettin , Güven Aytaç
Published: October 2008

A model for the acidolysis of trinolein and palmitic acid under the catalysis of immobilized sn-1,3 specific lipase was presented in this study. A neural networks (NN) based model was developed for the prediction of the concentrations of the major reaction products of this reaction (1-palmitoyl-2,3-oleoyl-glycerol (POO) 1,3-dipalmitoyl-2-oleoyl-glycerol (POP) and triolein (OOO)). Substrate ratio (SR), reaction temperature (T) and reaction time (t) were used as input parameters. The optimal architecture of the proposed NN model, which consists of one input layer with three inputs, one hidden layer with seven neurons and one output layer with three outputs, wass able to predict the reaction products concentration with a mean square error (MSE) of less than 1.5 and R2 of 0.999. and explicit formulation of the proposed NN is presented. Considerable good performance is achieved in modeling the acidolysis reaction using neuronal networks.
Flora del Pirineo aragonés. Patrones espaciales de biodiversidad y su relevancia para la conservación
Authors: García M. B. , Gómez D.
Published: October 2008

Se presenta un análisis de la distribución de la biodiversidad de plantas vasculares en el Pirineo aragonés. El área de estudio se sitúa en el centro de la cordillera, entre las regiones biogeográficas eurosiberiana y mediterránea, y muestra un desnivel altitudinal de 3.000 metros (400-3.400). Los 2.620 taxones registrados (103 endemismos pirenaicos, 10 de ellos exclusivos de la zona de estudio) a partir de unos 150.000 datos de presencia/ausencia, suponen más de un tercio de la flora total ibérica en apenas un 3% del territorio nacional peninsular. El 6,5% se pueden considerar plantas raras, mientras que el 7% son alóctonas y se sitúan en ambientes muy alterados. Los pastos, especialmente los supraforestales, se muestran como los hábitats con mayor riqueza específica. No obstante, si se tiene en cuenta la disponibilidad de superficie, destacan en densidad de taxones los humedales y megaforbios, así como roquedos y canchales. Más de la mitad de la flora se encuentra representada entre los 1.000-1.300 m de altitud, y tan solo el 17% se localiza en hábitats muy bien conservados. Estos últimos, sin embargo, contienen plantas de elevado valor por su grado de amenaza, singularidad taxonómica, o el interés biogeográfico de sus poblaciones. La superficie del Pirineo aragonés con alguna consideración oficial de protección supone el 34% y contiene al menos un 90% del conjunto de la flora, de los endemismos pirenaicos, y de la flora rara, así como un 80% de las localidades de flora catalogada. Sólo existe un solapamiento del 22% entre taxones catalogados y raros, lo que sugiere la necesidad de reevaluar el Catálogo Regional de Especies Amenazadas.
Cambios en la cubierta vegetal en el Pirineo aragonés en los últimos 50 años
Authors: Lasanta T. , Vicente-Serrano S. M.
Published: October 2008

En este trabajo se muestran los cambios de cubierta vegetal en el Pirineo occidental aragonés entre 1957 y 2007. La evolución se caracteriza por un importante proceso de revegetación con avance de los matorrales de sucesión y del bosque. Las laderas medias y bajas son las áreas con un proceso de revegetación más intenso, como consecuencia del abandono agrícola y la baja presión ganadera. Los avances más modestos tienen lugar en el espacio cultivado y pastos alpinos. Entre los años sesenta y ochenta ocurrieron los mayores cambios en la cubierta vegetal, habiéndose ralentizado en las dos últimas décadas. Los factores socioeconómicos (abandono agrícola, extensificación ganadera y reforestaciones) son los más influyentes, mientras que entre las naturales tiene especial importancia la exposición.
Variabilidad espacial de los efectos socioeconómicos de las explotaciones de esquí alpino en los municipios rurales del Pirineo aragonés
Authors: Lasanta T. , Laguna M. , Vicente-Serrano M.
Published: October 2008

Desde mediados del siglo XX se han impulsado las estaciones de esquí alpino en el Pirineo Aragonés, para incentivar las actividades turísticas y generar nuevas vías de desarrollo socio-económico. Transcurridos más de 30 años desde la construcción de las estaciones de esquí, cabe plantearse ¿en qué medida han contribuido a un desarrollo homogéneo en el territorio o han contribuido a desequilibrios espaciales? En este trabajo se estudian los efectos del turismo en la dinámica de la población (evolución del censo, cambios en la estructura demográfica y distribución de la población activa) y en el sector primario (evolución del número de explotaciones y de los censos ganaderos). Los resultados obtenidos en este trabajo permiten concluir que en el Pirineo Aragonés las estaciones de esquí afectan a un área espacial bastante reducida. En los municipios incluidos en ella se observan resultados positivos respecto a la evolución demográfica y negativos en el mantenimiento del sector primario. En los municipios no afectados por las estaciones de esquí, los resultados son totalmente diferentes, mostrando una evolución muy negativa de la población y positiva de los censos ganaderos.
Controllable Synthesis of Vertically Aligned p‐Type GaN Nanorod Arrays on n‐Type Si Substrates for Heterojunction Diodes
Authors: Tang Yong‐Bing , Bo Xiang‐Hui , Lee Chun‐Sing , Cong Hong‐Tao , Cheng Hui‐Ming , Chen Zhen‐Hua , Zhang Wen‐Jun , Bello Igor , Lee Shuit‐Tong
Published: October 2008

A new catalyst seeding method is presented, in which aerosolized catalyst nanoparticles are continuously self‐assembled onto amine‐terminated silicon substrates in gas phase to realize controllable synthesis of vertically aligned Mg‐doped GaN nanorod arrays on n‐type Si (111) substrates. The diameter, areal density, and length of GaN nanorods can be controlled by adjusting the size of Au nanoparticles, flowing time of Au nanoparticles, and growth time, respectively. Based on the synthesis of p‐type GaN nanorods on n‐type Si substrates, p‐GaN nanorod/n‐Si heterojunction diodes are fabricated, which exhibit well‐defined rectifying behavior with a low turn‐on voltage of ∼1.0 V and a low leakage current even at a reverse bias up to 10 V. The controllable growth of GaN nanorod arrays and the realization of p‐type GaN nanorod/n‐type Si heterojunction diodes open up opportunities for low‐cost and high‐performance optoelectronic devices based on these nanostructured arrays.
Multiple Pass‐Band Optical Left‐Handed Metamaterials Based on Random Dendritic Cells
Authors: Liu Baoqi , Zhao Xiaopeng , Zhu Weiren , Luo Wei , Cheng Xiaochao
Published: October 2008

Left‐handed metamaterials (LHMs) composed of random dendritic cells demonstrate a multi‐band resonance and negative refractive index. A nano‐assembly approach is established to fabricate optical LHMs. Random nanostructures of silver dendritic cells are prepared and further fabricated into a sandwich‐like structure with a dielectric medium. The dentritic nano‐assembled configuration reveals a multi‐band resonance and a high intensity of the pass‐band at infrared frequencies, and can be facilely and cheaply prepared on a large‐scale of effective area.
High Surface Area ZnO Nanoparticles via a Novel Continuous Precipitation Route
Authors: Kaluza Stefan , Schröter Marie Katrin , Naumann d'Alnoncourt Raoul , Reinecke Thomas , Muhler Martin
Published: October 2008

High surface area ZnO nanoparticles are synthesized by applying a novel continuous precipitation method using a micromixer coupled directly to a bench‐top spray dryer. The polycrystalline material is obtained by fast turbulent precipitation from aqueous zinc nitrate solutions with either sodium or potassium carbonate followed by immediate quenching of the aging due to the rapid water removal. Specific surface areas up to 98 m2 g−1 are obtained, depending on the precipitant and the sequence of unit operations applied after precipitation.
E proteins are required to activate germline transcription of the TCR Vβ8.2 gene
Authors: Jia Jingquan , Dai Meifang , Zhuang Yuan
Published: October 2008

Each TCR Vβ gene is regulated by an individual Vβ promoter, which becomes active prior to V(D) J recombination and drives germline transcription. It has been shown that Vβ gene locus activation and recombination are dependent on the Vβ promoter. However, transcription factors that regulate Vβ germline transcription remain largely undefined. A major challenge in studying Vβ gene germline transcription is the quantitative assessment of relatively low‐level transcripts in T‐cell progenitors. Here we used the established Vβ8.2CD2 knock‐in mouse model to assess functions of E‐protein transcription factors in Vβ8.2 germline transcription. We show that E proteins are required for the activation but not the maintenance of the Vβ8.2 germline transcription during thymocyte development. The activation of Vβ8.2 germline transcription depends more on the E proteins encoded by the E2A gene than by the HEB gene. We further show that IL‐7 receptor (IL‐7R)‐mediated signals are essential for Vβ8.2 germline transcription. We provide evidence that IL‐7R expression is only partially controlled by E2A, suggesting a role for E2A in driving Vβ8.2 germline transcription independent of IL‐7R activation.
IL‐4 inhibits VLA‐4 expression on Tc1 cells resulting in poor tumor infiltration and reduced therapy benefit
Authors: Sasaki Kotaro , Pardee Angela D. , Okada Hideho , Storkus Walter J.
Published: October 2008

We and others have previously demonstrated that IL‐4‐dependent Tc2 are inferior to Tc1‐effector CD8+ T cells in regulating tumor progression in vivo. This functional disparity relates, in part, to the comparatively poor ability of Tc2 to migrate into diseased tissues. We now show that IL‐4 treatment of committed Tc1 cells promotes the selective loss in the expression of very‐late antigen (VLA)‐4, without impacting the Tc1 cytokine production profile, cytotoxic activity, or expression of alternate cell surface markers. Down‐regulation of VLA‐4 expression on Tc1 cells was unique to treatment with IL‐4 (i.e. Tc1IL‐4) and did not occur in the presence of the Type‐2 cytokine IL‐13 or the regulatory cytokines IL‐10 or TGF‐β. Notably, the inhibitory effects of IL‐4 on Tc1 expression of VLA‐4 could be blocked by the presence of IL‐12, but not IFN‐γ. Predictably, Tc1IL‐4 (but not Tc1 control) cells adhere poorly to plate‐bound VCAM‐1‐Fc fusion protein and fail to be co‐stimulated by VCAM‐1 in vitro. They were also markedly impaired in their ability to traffic into intracranial melanoma lesions after adoptive transfer, yielding inferior therapeutic benefit to tumor‐bearing mice. These results suggest a novel suppressive mechanism for IL‐4 that limits Tc1 efficacy via preventing their recruitment into tumors.
Cover Picture: Eur. J. Immunol. 10/08
Authors: Chen Li , Wei Xiao‐Qing , Evans Bronwen , Jiang Wenguo , Aeschlimann Daniel
Published: October 2008

The cover image depicts multi‐nucleated osteoclasts stained for tartrate‐resistant alkaline phosphatase (maroon colour) after in vitro differentiation from bone marrow myeloid cells. The image was taken from the article of Chen et al. (pp. 2845–2854), in which the authors demonstrate that the proinflammatory IL‐12 family cytokine, IL‐23, up‐regulates RANK expression in myeloid precursor cells and sensitizes cells for commitment to the osteoclast lineage.
Capillary electropherograms for restriction fragment length polymorphism of Helicobacter Pylori
Authors: Bair Ming‐Jong , Chen Chiu‐Lin , Chiang Cheng‐Kang , Huang Ming‐Feng , Hu Cho‐Chun , Chang Huan‐Tsung
Published: October 2008

Rapid identification of Helicobacter pylori strains is of importance for diagnosis and then treatment of duodenal and gastric ulcers. We developed a CE approach for the analysis of RFLP of the PCR products of urease (UreAB) gene and flagellin A (FlaA) gene fragments. Prior to CE analysis, the 2.4‐kbp UreAB and 1.5‐kbp FlaA PCR products were digested with the restriction enzymes HaeIII and HhaI, respectively. The DNA fragments were then separated by CE in conjunction with laser‐induced fluorescence detection using poly(ethylene oxide) in the presence of electroosmotic flow. The DNA fragments range in sizes 259–1831 bp and 12–827 bp for UreAB and FlaA restriction fragments, respectively. Of 27 samples, the CE approach provided five and ten different RFLP patterns of the HaeIII and HhaI digests. The RFLP of PCR products of the two genes allow great sensitivity of identification of H. pylori strains. When compared with slab gel electrophoresis, the present CE approach provides advantages of rapidity (within 6 min per run), simplicity, and automation. The preliminary results have shown great practicality of the CE approach for screening H. pylori strains.
Monolithic and packed particle materials for in‐line pre‐concentration in capillary electrophoresis for 4‐hydroxy‐3‐methoxy‐methamphetamine and terbutaline
Authors: Chaisuwan Patcharin , Nacapricha Duangjai , Wilairat Prapin , Jiang Zhengjin , William Smith Norman
Published: October 2008

In‐line solid‐phase extraction (SPE) for capillary electrophoresis (CE) was investigated using a synthesized monolith and a commercial packing material. Terbutaline (TER) and 4‐hydroxy‐3‐methoxy‐methamphetamine (HMMA) with benzyl alcohol as the electroosmotic flow marker were employed as model compounds. Two types of methacrylate‐based monoliths, namely methacrylic acid‐ethylene dimethacrylate and butylmethacrylate‐ethylene dimethacrylate were examined. Preliminary results indicated that a non‐aqueous separating medium is more suitable for these methacrylate monoliths than a purely aqueous medium (non‐reproducible elution). However, coupling of the methacrylic acid‐ethylene dimethacrylate with non‐aqueous capillary electrophoresis could not provide good precision for the three model compounds. A packed‐silica C18 SPE was also adopted by simply packing the C18 particles in situ in the separation capillary. Using an aqueous running buffer (10 mM phosphate buffer (PPB), pH 7), acceptable precision could be obtained with this type of SPE material. With a 10 min loading time and 20 min total analysis time, the pre‐concentration factors were 333 and 1000 for TER and HMMA, respectively. The %RSD were less than 4.5 and 0.3 for the peak areas and migration times, respectively, for both HMMA and TER (n=20).
Evaluation of antioxidative capability of the tomato (Solanum lycopersicum) skin constituents by capillary electrophoresis and high‐performance liquid chromatography
Authors: Helmja Kati , Vaher Merike , Püssa Tõnu , Raudsepp Piret , Kaljurand Mihkel
Published: October 2008

In the current study, phenolic compounds of the tomato (Solanum lycopersicum) skin extract were separated and their composition was determined by capillary electrophoresis and tandem high‐performance liquid chromatography diode array detection‐mass spectrometry (HPLC‐DAD‐MS/MS). Both the total phenolic and flavonoid contents of the extract were determined. The antioxidative capability of the extract was measured using a stable free radical 2,2‐diphenyl‐1‐picrylhydrazyl assay. The monitoring of the radical scavenging capability of specific phenolic compounds was carried out both by capillary electrophoresis and HPLC‐MS/MS.
A novel QSPR study of normalized migration time for drugs in capillary electrophoresis by new descriptors: Quantum chemical investigation
Authors: Riahi Siavash , Beheshti Abolghasem , Ganjali Mohammad Reza , Norouzi Parviz
Published: October 2008

Some drugs' migration time (MT) has been studied employing quantitative structure–property relationship using new descriptors that are able to predict MT value with high accuracy. MT property modeling of the drugs was established as a function of the new theoretically derived descriptors applying multiple linear regressions and partial least‐squares regression. The genetic algorithm was used to select those variables that resulted in the best‐fitted models. To select a set of descriptors that are most relevant to MT, illustrating the affecting degree for the affinity of different descriptors, the linear models with 1–14 variables were constructed and were then investigated based on F‐value, squared regression coefficients of cross‐validated (Q2), adjusted R2 (R2adj) and standard error of estimate (S) statistical parameters. Finally, the best model with ten variables was selected. Statistical parameters of the test set, such as standard deviation error in test, were 0.559 and 0.616, while relative error of test was equal to 7.648 and 8.497% for multiple linear regressions and partial least‐squares models, respectively, confirming the good predictive ability of the model. Since the capillary lengths were not the same for the drugs in the data set, MT values were normalized based on a specific capillary before modeling, which is also one of the advantages of this method, enabling us to use the model for different capillary lengths.
Quantitative investigations on moving chelation boundary within a continuous EDTA‐based sample sweeping system in capillary electrophoresis
Authors: Fan Liuyin , Li Chenjia , Zhang Wei , Cao Chengxi , Zhou Pei , Deng Zixin
Published: October 2008

Recently, the EDTA‐based sweeping of metal ion that combines chelate formation and in‐line sample pre‐concentration was advanced. However, the moving chelation boundary (MCB) existing in the sweeping system has not been investigated for the quantitative illumination of the mechanism of metal ion sweeping yet. In this paper, the model of MCB was developed from the EDTA‐based sweeping. The theoretical studies were performed for boundary movements and controllable sweeping of metal ion. The theoretical studies show that the sweeping system contains the MCB boundary and chelate boundary, and the difference between the MCB and chelate boundary velocities plays a key role in the stacking efficiency of metal ion. To demonstrate the validity of the theoretical conclusion, the experiments of continuous EDTA‐based sweeping were performed with CE and a home‐made apparatus of a large tube. The home‐made apparatus consisted of a glass tube used for the run of continuous EDTA‐based sweeping and two peristaltic pumps used for the supply of solution. The experimental results were in accordance with the theoretical conclusions above. The developed theory holds evident for significance for the mechanism of controllable stacking of metal ions in EDTA‐based sweeping system in CE.
Capillary zone electrophoresis (CZE) coupled to time‐of‐flight mass spectrometry (TOF‐MS) applied to the analysis of illicit and controlled drugs in blood
Authors: Gottardo Rossella , Polettini Aldo , Sorio Daniela , Pascali Jennifer Paola , Bortolotti Federica , Liotta Eloisa , Tagliaro Franco
Published: October 2008

A new method for the determination of illicit and abused drugs in blood by capillary zone electrophoresis–electrospray ionization–time‐of‐flight mass spectrometry is proposed, in view of its application in clinical and forensic toxicology. The analytes (methamphetamine, methylenedioxyamphetamine, methylenedioxyethylamphetamine, methylenedioxymethamphetamine, methadone, cocaine, morphine, codeine, 6‐acethylmorphine, benzoylecgonine) were separated with capillary zone electrophoresis by applying 15 kV within 25 min, in an uncoated fused‐silica capillary (75 μm × 100 cm) using a 25 mM ammonium formate electrolyte solution (pH 9.5). The capillary electropherograph was coupled to time‐of‐flight mass spectrometry through an orthogonal electrospray ionization source, with a coaxial sheath liquid interface. The sheath liquid was composed of isopropanol‐water (1:1 v/v) containing 0.5% formic acid delivered at 4 μL/min. Forensic drugs were identified by exact mass determination (mass accuracy typically ≤5 ppm) and by matching of the isotopic pattern.

Under optimized conditions, linearity was assessed in the range 10–2000 ng/mL, with correlation coefficients between 0.9744 and 0.9982 for all the analytes. LODs were in the range of 2–10 ng/mL (S/N ≥3) and LOQs of 10–30 ng/mL. The CVs (tested at 40 and 800 ng/mL in biological matrix) were below 2.97% for migration times and below 14.61% for peak area ratios (analyte/internal standard). Blood samples were extracted by using a liquid–liquid extraction procedure and injected under field‐amplified sample stacking conditions. The method was successfully applied to real cases.
The role of cysteine and cysteine–S conjugates as odour precursors in the flavour and fragrance industry
Authors: Starkenmann Christian , Troccaz Myriam , Howell Kate
Published: October 2008

Volatile sulphur compounds are important odorants in the flavour and fragrance industries. Recent developments in the field have reinvigorated sulphur compound research, particularly with regard to the precursor compounds of volatile thiols. The present review concentrates on the role of cysteine and cysteine–S conjugates as precursor compounds for a variety of aromas and examines the chemical and enzymatic pathways of degradation and biotransformation. Cysteine is an important source of sulphur in flavour chemistry and may be degraded into hydrogen sulphide, which can further participate in other reactions. Direct reactions of cysteine and the pathways particular to various flavours and fragrances are discussed, with an emphasis on the precursor compounds cysteine–S conjugates. The importance of cysteine precursors in plants, including onion, wine, passion fruit, bitter orange, asparagus and bell pepper and the formation of natural scents in cats and humans are discussed. Copyright © 2008 John Wiley & Sons, Ltd.
Forgetting the learning curve for a moment: how much performance is unrelated to own experience?
Authors: Huesch Marco D. , Sakakibara Mariko
Published: October 2008

Volume–outcome relationships are of clear importance for most participants in the health‐care industry; research and appropriate policy implications are of critical importance. In this letter we critique the prevailing ‘learning‐by‐doing’ view in cardiac surgery. We illustrate the very wide disparity in empirical findings on volume–outcome relationships there, in the context of broader open issues in ‘learning curves’ in general. Potential complementary mechanisms, e.g. ‘social learning by knowledge spillovers’ are introduced; these cast into doubt the prevailing policy recommendations of simple regionalization and volume smoothing. Copyright © 2008 John Wiley & Sons, Ltd.
First‐year quality of life assessment of an intra‐arterial (RADPLAT) versus intravenous chemoradiation phase III trial
Authors: Ackerstaff Annemieke H. , Balm Alfons J. M. , Rasch Coen R. N. , de Boer Jan Paul , Wiggenraad Ruud , Rietveld Derk H. F. , Gregor R. Theo , Kröger Robert , Hilgers Frans J. M.
Published: October 2008

Background.

We report the results of a multicenter randomized phase III study, assessing quality of life (QOL) in intra‐arterial (IA) versus standard intravenous (IV) chemoradiation in advanced head and neck cancer.

Methods.

Two hundred seven patients with inoperable stage IV disease—152 men and 55 women; mean age, 55 years—were included in this study. The patients were treated with standard radiotherapy with 4 weekly IA or 3 weekly IV cisplatin infusions. The QOL assessments carried out were EORTC‐C30, H&N35, and trial‐specific questionnaires.

Results.

Overall QOL deteriorated in all patients during treatment, is gradually improving over 1 year. IA patients showed significantly less nausea and vomiting at week 7 (p <.001). IV patients were significantly more fatigued (p <.006). At 1 year, no significant difference in tube feeding was found. Voice quality slightly exceeded the pretreatment values at 1 year. Forty‐two of 62 employed patients returned to work.

Conclusion.

During treatment, significantly fewer problems with nausea and vomiting occurred in IA than in IV patients. Both groups showed improved voicing and oral intake during follow‐up, often exceeding pretreatment values at 1 year. © 2008 Wiley Periodicals, Inc. Head Neck, 2009
Validation of the EORTC QLQ‐C30 and EORTC QLQ‐H&N35 in patients with laryngeal cancer after surgery
Authors: Singer Susanne , Wollbrück Dorit , Wulke Cornelia , Dietz Andreas , Klemm Eckart , Oeken Jens , Meister Eberhard F. , Gudziol Hilmar , Bindewald Julian , Schwarz Reinhold
Published: October 2008

Background.

The aim of this study was to test the validity of the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire, Core Module (QLQ‐C30) and Head and Neck Module (QLQ‐H&N35) for patients who have undergone surgery due to laryngeal cancer.

Methods.

A total of 323 patients from 6 different centers in Germany who had been operated on completed the QLQ‐C30 and the QLQ‐H&N35 in addition to being surveyed in a personal interview.

Results.

Multitrait scaling analysis confirmed the proposed scale structure of both questionnaires. Cronbach's alpha of the QLQ‐C30 scales ranged from 0.64 (Cognitive Functioning) to 0.94 (Global Health Status); the alpha of the QLQ‐H&N35 ranged from 0.55 (Speech) to 0.90 (Sexuality). Known‐groups comparisons showed multiple differences in sociodemographic and clinical variables.

Conclusion.

It can be concluded that the QLQ‐H&N35, in conjunction with the QLQ‐C30, is a reliable instrument that is able to differentiate between diverse groups of patients with laryngeal cancer after surgery. © 2008 Wiley Periodicals, Inc. Head Neck, 2009
Diphenyl diselenide protects against hematological and immunological alterations induced by mercury in mice
Authors: Brandão Ricardo , Borges Lysandro Pinto , Oliveira Renata de , Rocha João B. T. , Nogueira Cristina W.
Published: October 2008

Mercury is a heavy metal that can cause a variety of toxic effects on the organism, such as hematological and immunological alterations. In the present investigation, deleterious effects of mercury‐intoxication in mice and a possible protective effect of diphenyl diselenide (PhSe)2 were studied. Male adult Swiss albino mice received daily a pretreatment with (PhSe)2 (15.6 mg/kg, orally) for 1 week. After this week, mice received daily mercuric chloride (1 mg/kg, subcutaneously) for 2 weeks. A number of hematological (erythrocytes, leukocytes, platelets, hemoglobin, hematocrit, reticulocytes, and leukocytes differential) and immunological (immunoglobulin G and M plasma concentration) parameters were evaluated. Another biomarker of tissue damage, lactate dehydrogenase (LDH), was also determined. The results demonstrated that mercury exposure caused a reduction in the erythrocyte, hematocrit, hemoglobin, leukocyte, and platelet counts and an increase in the reticulocyte percentages. (PhSe)2 was effective in protecting against the reduction in hematocrit, hemoglobin, and leukocyte levels. (PhSe)2 ameliorated reticulocyte percentages increased by mercury. However, (PhSe)2 was partially effective in preventing against the decrease in erythrocyte and platelet counts. Immunoglobulin G and M concentrations and LDH activity were increased by mercury exposure, and (PhSe)2 was effective in protecting against these effects. In conclusion, (PhSe)2 was effective in protecting against hematological and immunological alterations induced by mercury in mice. © 2008 Wiley Periodicals, Inc. J Biochem Mol Toxicol 22:311–319, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/jbt.20242
Proteomic analysis of Latrodectus tredecimguttatus venom for uncovering potential latrodectism‐related proteins
Authors: Duan Zhigui , Yan Xiaojun , Cao Rui , Liu Zhen , Wang Xianchun , Liang Songping
Published: October 2008

Black widow spider is one of the most poisonous spiders in the world. Up to now, there have been few systematic analyses of the spider venom components, and the mechanism of action of the venom has not been completely understood. In this work, we employed combinative proteomic strategy to analyze the venom collected from living adult spider Latrodectus tredecimguttatus by electrical stimulation. The experiments demonstrated that the venom is primarily composed of high molecular weight proteins and has high abundance proteins around 100 kDa. The content of peptides and proteins with low molecular weight is low. A total of 75 nonredundant venom proteins with distinct function were unambiguously identified. Besides the known black widow spider venom proteins including latrotoxins, a variety of hydrolases and other proteins with special activity were found in the venom, such as proteinase, phospholipase, phosphatase, nuclease, fucolectin, venom allergen antigen 5‐like protein and trypsin inhibitor, and so on. Their possible biological actions and relationship with latrodectism were discussed. The results help to understand the complexity and action mechanism of L. tredecimguttatus venom. © 2008 Wiley Periodicals, Inc. J Biochem Mol Toxicol 22:328–336, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/jbt.20244
Biochemical effects of gestational coexposure to lead and cadmium on reproductive performance, placenta, and ovary
Authors: Nampoothiri Laxmipriya P. , Gupta Sarita
Published: October 2008

Adult virgin 4‐day cycling synchronized Charles foster females were treated subcutaneously (0.05 mg/kg body wt/day) with sodium acetate (control), lead acetate or cadmium acetate alone, or both during gestational period, with pretreatment of 5 days prior to mating. There were no alterations in reproductive performance in all metal‐treated groups. Implantation enzymes, cathepsin‐D and alkaline phosphatase, activity were altered, but no change in the reproductive performance was observed. The key steroidogenic enzymes of ovary and placenta (3β‐HSD and 17β‐HSD), along with gonadal steroids, were affected the most in cadmium and combined treated animals whereas lead‐treated animals showed a minimum change compared to the control group. Maximum displacement of zinc bound to metallothionein was more in cadmium and combined treated rats when compared to other metal‐treated groups. Biomolecules such as glycogen, protein, RNA, DNA, and protein content were affected in all metal‐treated groups, whereas cadmium‐treated animals showed greater effect. General parameters of toxicity such as alkaline phosphatase, serum glutamate pyruvate transaminase, and creatinine were altered but were within the normal range. Biochemical effects are correlated with metals accumulated in blood, reproductive tissue such as placenta and ovary. © 2008 Wiley Periodicals, Inc. J Biochem Mol Toxicol 22:337–344, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/jbt.20246
Effect of copper intoxication on rat liver proteasome activity: Relationship with oxidative stress
Authors: Alexandrova Albena , Petrov Lubomir , Georgieva Almira , Kessiova Mila , Tzvetanova Elina , Kirkova Margarita , Kukan Marian
Published: October 2008

Copper toxicity is associated with formation of reactive oxygen species, which are capable to oxidize proteins. The selective removal of the latter by the 20S proteasome is considered an essential part of the cell antioxidant defense system. The aim of the present study was to investigate whether peptidase activities of rat liver proteasomes were affected by chronic (40 mg CuSO4/rat/daily with the drinking water for 2 weeks) and acute (20 mg/kg CuSO4, s.c.) copper treatment. To evaluate the role of proteasome, its inhibitor MG132 was also used. The degree of copper‐induced oxidative stress (OS), established by measuring lipid peroxidation, protein oxidation, and cellular glutathione level, as well as activities of antioxidant enzymes—catalase, superoxide dismutase, and gultathionine peroxidase, depended on the mode of copper administration. Chronic copper administration (mild oxidative stress) did not affect proteasome activities, whereas acute copper treatment (severe oxidative stress) caused a decline in chymotryptic‐ and tryptic‐like activities. The treatment of copper‐loaded animals with MG132 did not change copper‐induced alterations in the tested indices, except an additional increase in protein oxidation and inhibition of glutathionine peroxidase activity. The results suggested that the in vivo copper‐induced oxidative stress was associated with changes in the catalytic activity of proteasome. © 2008 Wiley Periodicals, Inc. J Biochem Mol Toxicol 22:354–362, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/jbt.20248