bluuebunny/crossref_metadata_2025_split huggingface dataset:
Enhancer‐deleted retroviral vectors restore high levels of superoxide generation in a mouse model of CGD
Authors: Schwickerath Oliver , Brouns Gaby , Thrasher Adrian , Kinnon Christine , Roes Jürgen , Casimir Colin 
Published: March 2004

AbstractBackgroundRetroviral vectors possess many advantages for use in gene therapy protocols, especially within the haematopoietic system. A number of attendant problems, however, still limit their safety in clinical application. The effects of the enhancer present in the retroviral long terminal repeat (LTR) are a major concern for the clinical usage of such vectors, as they can exert a powerful regulatory influence on the genes that surround them.MethodsTo improve the safety and widen the applicability of retroviral vectors for use in gene therapy we have developed an enhancer‐deleted (Δ‐LTR) retroviral vector that retained high titre and demonstrated transcriptional activity in myeloid cells.ResultsWhen used to correct a mouse model of autosomal recessive chronic granulomatous disease, the Δ‐LTR vectors gave acceptable levels of gene transfer to mouse bone marrow cells. Evidence for a slight preferential expression in myeloid cells was obtained with all the vectors studied. Nitroblue tetrazolium assay of superoxide generation in mouse bone marrow derived haematopoietic colonies revealed that transduction with Δ‐LTR vectors could restore functional NADPH oxidase to cells from these animals. Superoxide assay of peripheral blood confirmed that, although relatively low numbers of cells were transduced, the Δ‐LTR vector was capable of reconstituting very high levels of oxidase activity, comparable to that obtained from normal cells.ConclusionsThe Δ‐LTR vector described here could provide the basis for a new generation of retroviral vectors with improved safety. Copyright © 2004 John Wiley & Sons, Ltd.
Synthesis of [uniformly ring‐14C]‐labelled 4‐hydroxybenzaldehyde, vanillin, and protocatechualdehyde
Authors: Ji Rong , Schäffer Andreas 
Published: March 2004

Abstract[Uniformly ring‐14C]‐labelled 4‐hydroxybenzaldehyde, vanillin, and protocatechualdehyde were synthesized from [14C]‐labelled phenol, guaiacol, and catechol with methyl dichloromethyl sulfide (CH3SCHCl2) under Friedel–Crafts alkylation conditions in dichloromethane at −78°C for 5 min (in the case of phenol and guaiacol) or at −20°C for 1 min (in the case of catechol), by rapid addition of SnCl4 to mixtures of the phenolic compound and CH3SCHCl2, followed by hydrolysis with HCl. Regioselective formylation (para to the –OH group) was achieved. The conversion rates were 96, 81, and 88% for 4‐hydroxybenzaldehyde, vanillin, and protocatechualdehyde, respectively, and the yields of the recovered products after work‐up amounted to 88, 75, and 83%, respectively. In the case of guaiacol, 17% of isovanillin was obtained as by‐product. It was found that the presence of water or ethyl acetate in the reaction mixture, at a molar ratio of 60:1 (water:guaiacol) or 120:1 (ethyl acetate:guaiacol), had little influence on the yields under the reaction conditions. Factors influencing the yields are discussed in the study. Copyright © 2004 John Wiley & Sons, Ltd.
Substitution‐reduction: an alternative process for the [18F]N‐(2‐fluoroethylation) of anilines
Authors: Briard Emmanuelle , Pike Victor W. 
Published: March 2004

AbstractSubstitution of a halo atom (chloro or bromo) in easily prepared N‐haloacetyl‐anilines with no‐carrier added (NCA) cyclotron‐produced [18F]fluoride ion (18F, t1/2= 109.8 min; β+=96.9%), followed by reduction with borane–tetrahydrofuran (BH3–THF), provides an alternative route to NCA [18F]N‐(2‐fluoroethyl)‐anilines. This two‐step and one‐pot process is rapid (∼50 min) and moderately high yielding (∼40% decay‐corrected radiochemical yield (RCY) overall). In the nucleophilic substitution reaction, 18‐crown‐6 is preferred to Kryptofix® 222 as complexing agent for the solubilization of the counter‐ion (K+), derived from an added metal salt, in acetonitrile. Weakly basic potassium bicarbonate is preferred as the added metal salt. Inclusion of a small amount of water, equating to 4–5 molar equivalents relative to 18‐crown‐6, base or precursor (held in equimolar ratio), is beneficial in preventing the adsorption of radioactivity onto the wall of the glass reaction vessel and for achieving high RCY in the nucleophilic substitution reaction. BH3–THF is effective for the rapid reduction of the generated [18F]N‐fluoroacetyl‐aniline to the [18F]N‐(2‐fluoroethyl)‐aniline. Copyright © 2004 John Wiley & Sons, Ltd.
Dibenzocyclooctadiene lignans from Schisandra chinensis protect primary cultures of rat cortical cells from glutamate‐induced toxicity
Authors: Kim So Ra , Lee Mi Kyeong , Koo Kyung Ah , Kim Seung Hyun , Sung Sang Hyun , Lee Na Gyong , Markelonis George J. , Oh Tae H. , Yang Jae Ho , Kim Young Choong 
Published: March 2004

AbstractA methanolic extract of dried Schisandra fruit (Schisandra chinensis Baill.; Schisandraceae) significantly attenuated the neurotoxicity induced by L‐glutamate in primary cultures of rat cortical cells. Five dibenzocyclooctadiene lignans (deoxyschisandrin, gomisin N, gomisin A, schisandrin, and wuweizisu C) were isolated from the methanolic extract; their protective effects against glutamate‐induced neurotoxicity were then evaluated. Among the five lignans, deoxyschisandrin, gomisin N, and wuweizisu C significantly attenuated glutamate‐induced neurotoxicity as measured by 1) an inhibition in the increase of intracellular [Ca2+]; 2) an improvement in the glutathione defense system, the level of glutathione, and the activity of glutathione peroxidase; and 3) an inhibition in the formation of cellular peroxide. These results suggest that dibenzocyclooctadiene lignans from Schisandra chinensis may possess therapeutic potential against oxidative neuronal damage induced by excitotoxin. © 2004 Wiley‐Liss, Inc.
Characteristics of fruit and oil of terebinth (Pistacia terebinthus L) growing wild in Turkey
Authors: Özcan M 
Published: March 2004

AbstractNutrients and physical properties were determined in terebinth (Pistacia terebinthus L) fruits from İçel, Turkey to investigate their potential uses. Ripe fruits were evaluated for moisture, crude protein, crude oil, crude fibre, crude energy, ash, HCl‐insoluble ash, essential oil yield, dimethyl sulphite, weight and width/length ratio. Relative density, refractive index, free fatty acids, peroxide value, iodine value, saponification number, unsaponifiable matter and carotenoid content were determined in the fruit oil. The main fatty acids identified by gas chromatography were oleic (52.3%), palmitic (21.3%) and linoleic (19.7%) acids. Contents of Na, K, P, Ca, Fe, Mg, Zn, Cu, Mn, Li, Ni, Pb, S, Se, Cd, Co, Cr, Sr, Ti, V, Ag, Al, As, B, Ba and Bi were also determined in the fruits. The fruits were found to be rich in protein, oil, fibre, unsaturated fatty acids and minerals, suggesting that they may be valuable for food uses. The data may also be useful for the evaluation of nutritional information. Copyright © 2004 Society of Chemical Industry
Ensilage as a means of reducing the concentration of cyanogenic glycosides in the pods of Acacia sieberiana and the effect of additives on silage quality
Authors: Ngwa Thomas A , Nsahlai Ignatius V , Iji Paul A 
Published: March 2004

AbstractCyanogenic glycosides are anti‐nutritional components capable of liberating hydrogen cyanide, a respiratory poison that has been reported to be responsible for the death of livestock that browse some Acacia species containing these compounds. The objective of the study was to improve the nutritive value of the pods of Acacia sieberiana by reducing their contents of cyanogenic glycosides through ensiling, and to examine the influence of various levels of added molasses and urea on the aerobic stability of the silage. In experiment 1, laboratory silages, prepared by mixing ground pods with water in two ratios (60:40 and 40:60 w/w pod material:water), were put into 250 ml polythene bottles, ensiled for 4, 7, 14, 21, 28 or 35 days and analyzed for cyanide. In experiment 2, silages prepared as described above but using only one of the ratios (40:60), and with the addition of molasses (0, 30 or 60 g kg−1) and urea (0, 2.5 or 50 g kg−1) were included in a 3 × 3 factorial design, to study the effects of these additives on the stability of the silage. The period of ensilage was 14 days. In experiment 3, the concentrations of molasses and urea were modified to 0, 45 or 90 g kg−1 and 0, 7.5 or 15 g kg−1, respectively, and the period of ensilage was extended to 45 days. The parent material contained 130.6 mg CN kg−1 DM and ensiling the material for 35 days reduced the concentration to 18.1 mg CN kg−1 DM. Moisture content at ensiling significantly (P < 0.001) affected the concentration of cyanide in the stored silages. Silages opened after 14 days were unstable irrespective of the use of additives. However those with combined urea and molasses exhibited a slow rate of deterioration and low fungal counts. Extending the period of ensiling to 45 days improved the aerobic stability of all the silages. The addition of urea significantly (P < 0.001) increased the pH, crude protein content, gross energy and fermentation acids while molasses treatment increased (P < 0.001) the lactic acid and ash content of the silages. Ensiling ground pods for 45 days was enough to reduce the cyanide content to non‐toxic levels and produced a silage which was aerobically stable, while the inclusion of additives further improved the quality of the silages. Copyright © 2004 Society of Chemical Industry
Off‐flavour development in soybeans: comparative role of some antioxidants and related enzymes
Authors: Dahuja Anil , Madaan Tilak R 
Published: March 2004

AbstractOff‐flavour development is the major impediment in the effective use of soybeans as food ingredients. In the present study, the levels of vitamin E and vitamin C along with those of antioxidant enzymes, like superoxide dismutase, peroxidase and catalase, were estimated in sixteen soybean varieties to explore their effectiveness against off‐flavour generation. Thiobarbituric acid (TBA) number, an indicator of lipid peroxidation, was used to measure the quality with respect to off‐flavour. Data on activities of various antioxidant enzymes indicated that the off‐flavour is mainly generated enzymatically by the action of lipoxygenase on polyunsaturated fatty acids. Furthermore, varieties PK 416 and JS 7105 had the highest level of vitamin E while their TBA number was the lowest indicating the inverse relationship between the two parameters. It was further observed that the peroxidative effect of higher vitamin C concentrations is controlled by vitamin E. Among the varieties analyzed, PK 416 and JS 7105 appeared to have greater potential as most acceptable food ingredients. Copyright © 2004 Society of Chemical Industry
Effect of flaxseed processing on its true metabolizable energy values for adult chicken
Authors: Shen Yingran , Feng Dingyuan , Chavez Eduardo R 
Published: March 2004

AbstractThe objective of the present experiment was to study the effect of flaxseed processing on nitrogen corrected true metabolizable energy (TMEn) values for adult roosters. Flaxseed was processed as pelleted, autoclaved or microwave roasted. Leghorn roosters were used for the TME determination procedure. The TMEn value of flaxseed batch A, 14.48 MJ kg−1 DM, was significantly (P < 0.05) increased to 17.89 MJ kg−1 DM by three‐time repeat‐pelleting, or to 18.07 MJ kg−1 dry matter (DM) by autoclaving, respectively. Microwave roasting also significantly (P < 0.05) increased the TMEn value of flaxseed batch B by 22%. The TMEn improvement observed due to processing was accompanied by increased ether extract utilization. The apparent ether extract digestibility of flaxseed batch A, 61.2%, was very significantly (P < 0.01) increased to 81.5 and 83.2% by processing as repeat‐pelleting and autoclaving, respectively. Microwave roasting also significantly (P < 0.05) increased the apparent digestibility of ether extract for flaxseed batch B from 49.1 to 64.4%. Proper flaxseed processing as pelleting, autoclaving and microwave roasting led to higher TMEn values for Leghorn roosters, mainly as the result of increased ether extract utilization. Copyright © 2004 Society of Chemical Industry
Effects of stage II and postharvest deficit irrigation on peach quality during maturation and after cold storage
Authors: Gelly M , Recasens I , Girona J , Mata M , Arbones A , Rufat J , Marsal J 
Published: March 2004

AbstractEffects of regulated deficit irrigation (RDI) on the quality of a mid–late maturing peach (Prunus persica L Batsch cv Andross) were determined at commercial harvest as well as 1 week before (early pick‐up) and after 1 week of cold storage. Respiration and ethylene evolution were measured during 96 h on fruits sampled at early pick‐up and at harvest. Fruits from a well‐watered irrigation treatment (Control) were compared with a treatment of RDI during stage II of fruit growth (RDI‐SII) and with RDI applied postharvest (RDI‐PH). A fourth treatment received a combination of deficit irrigation applied during stage II and postharvest (RDI‐SII‐PH). Higher soluble solids content (SSC) amd SSC/titratable acidity (TA) ratio for RDI‐SII were already noted at early pick‐up and these differences were enhanced after cold storage (RDI fruits having higher SSC, lower TA and higher SSC/TA ratio than Control fruits). This improvement in quality (high SSC/TA ratio) was also correlated with a more reddish colouration in the fruit skin. Moreover, ethylene production indicated different behaviour of the physiological evolution for fruits from the different treatments. Copyright © 2004 Society of Chemical Industry
Application of a polymerase chain reaction (PCR) method as a complementary tool to microscopic analysis for the detection of bones and other animal tissues in home‐made animal meals
Authors: Prado Marta , Casqueiro José , Iglesias Yolanda , Cepeda Alberto , Barros‐Velázquez Jorge 
Published: March 2004

AbstractA polymerase chain reaction (PCR) method was compared with a variation of the official microscopic technique (Directive 98/88/EC) for the detection in animal meals of cereals (wheat and corn) and animal parts (bone, feathers, meat, liver, fat and blood). Microscopy successfully detected animal bones in raw feeds with a sensitivity of 1 g kg−1, while the sensitivity of the PCR method was in the range of 5–10 g kg−1. Microscopy also allowed the detection of animal bones and feathers in feeds processed at 115 and 133 °C but failed to detect other animal materials. The PCR method successfully detected cereals (wheat and corn) as well as meat, bone, liver, fat and feathers after processing at 115 °C for 20 min. Heating at 133 °C under overpressure (autoclave) conditions resulted in more intense DNA fragmentation and lower DNA extractability. Nevertheless, bone and liver, as well as wheat and corn in home‐made animal meals, were successfully detected even after heating at 133 °C for 20 min. Copyright © 2004 Society of Chemical Industry
The effect of germination on seed trypsin inhibitors in Vicia faba and Cicer arietinum
Authors: Muzquiz Mercedes , Welham Tracey , Altares Pilar , Goyoaga Carmen , Cuadrado Carmen , Romero Concepción , Guillamon Eva , Domoney Claire 
Published: March 2004

AbstractDuring germination, trypsin inhibitor (TI) content increased relative to total protein and dry weight in cotyledons from two varieties of Vicia faba. These data, together with changes in total protein profiles and amounts, suggest that TI proteins are not hydrolysed in parallel with other seed proteins and dry matter. In contrast, TI content in germinating Cicer arietinum seeds remained constant during the germination period; in this case, however, substantial changes in the total protein profile were not observed. TI isoform analyses indicated that compositional changes occurred during germination in both species. Copyright © 2004 Society of Chemical Industry
Yield and biosynthesis of nitrogenous compounds in fruits of green bean (Phaseolus vulgaris L cv Strike) in response to increasing N fertilisation
Authors: Sánchez Esteban , Rivero Rosa M , Ruiz Juan M , Romero Luis 
Published: March 2004

AbstractThe objective of the present work was to determine the effect of different dosages of N on the biosynthesis of organic N compounds in fruits and their influence on yield in green bean (Phaseolus vulgaris L cv Strike) plants. The nitrogen was applied to the nutrient solution as NH4NO3 at 1.5 (N1), 3 (N2), 6 (N3), 12 (N4), 18 (N5) and 24 mM (N6). Treatment N3 was considered optimal for efficient yield in green bean plants and also for the null presence of NO3−. Highest N dosages (18 and 24 mM) resulted in the accumulation of NO3− in pods and seeds. This accumulation encouraged nitrate reductase (NR) and nitrite reductase (NiR) activity in both tissues and treatments, and therefore NR activity might be considered as a good bioindicator of the presence of NO3− in edible fruits. The greater NH4+ assimilation by glutamine synthetase (GS) and glutamate synthase (GOGAT) occurred primarily in the pods of the N6 treatment, while the seeds acted as physiological sinks, these latter tissues presenting the highest concentrations of amino acids, proteins and organic N. The high accumulation of NO3− and NH4+ in both seeds and pods could be the direct cause of the reduction in fruit production, indicating that green bean plants are very sensitive to high N levels. Copyright © 2004 Society of Chemical Industry
Quantification of naphthalenes in jet fuel with GC×GC/Tri‐PLS and windowed rank minimization retention time alignment
Authors: Johnson Kevin J. , Prazen Bryan J. , Young Donald C. , Synovec Robert E. 
Published: March 2004

AbstractComprehensive, two‐dimensional gas chromatography (GC×GC) is used in conjunction with trilinear partial least squares (Tri‐PLS) to quantify the percent weight of naphthalenes (two‐ring aromatic compounds) in jet fuel samples. The increased peak capacity and selectivity of GC×GC makes the technique attractive for the rapid, and possibly less tedious analysis of jet fuel. The analysis of complex mixtures by GC×GC is further enhanced through the use of chemometric techniques, including those designed for use on 2‐D data such as Tri‐PLS. Unfortunately, retention time variation, unless corrected, can be an impediment to chemometric analysis. Previous work has demonstrated that the effects of retention time variation can be mitigated in sub‐regions of GC×GC chromatograms through the application of an objective retention time alignment algorithm based on rank minimization. Building upon this previous work, it is demonstrated here that the effects of retention time variation can be mitigated throughout an entire GC×GC chromatogram with an objective retention time alignment algorithm based on windowed rank minimization alignment. A significant decrease in calibration error is observed when the algorithm is applied to chromatograms prior to construction of Tri‐PLS models. Fourteen jet fuel samples with known weight percentages of naphthalenes (ASTM D1840) were obtained. Each sample was subjected to five replicate five‐minute GC×GC separations over a period of two days. A subset of nine samples spanning the range of weight percentages of naphthalenes was chosen as a calibration set and Tri‐PLS calibration models were subsequently developed in order to predict the naphthalene content of the samples from the GC×GC chromatograms of the remaining five samples. Calibration models constructed from GC×GC chromatograms that were retention time corrected are shown to exhibit a root mean square error of prediction of roughly half that of calibration models constructed from uncorrected chromatograms. The error of prediction is lowered further to a value that nearly matches the uncertainty in the standard percent weight values (ca. 1% of the median percent volume value) when the aligned chromatograms are truncated to include only regions of the chromatogram populated by naphthalenes and compounds of similar polarity and boiling point.
Assessment by Monte Carlo simulation of thermodynamic correlation of retention times in dual‐column temperature programmed comprehensive two‐dimensional gas chromatography
Authors: Davis Joe M. 
Published: March 2004

AbstractThe correlation of retention times in comprehensive two‐dimensional gas chromatography caused by correlation of enthalpy and entropy changes between two stationary phases, methylsilicone and poly(ethylene glycol), was examined using commercial GC software and in‐house Monte Carlo simulation. The enthalpy change, ΔH 0, and entropy change, ΔS 0, of 93 compounds were predicted from isothermal one‐dimensional gas chromatograms predicted by the software. These values then were mimicked by Monte Carlo simulation, which removed the strong correlation of ΔH 0 and modest correlation of ΔS 0 between the two phases. Retention times in a comprehensive two‐dimensional gas chromatogram (GC×GC) and in simulations of it were predicted for typical dual‐capillary temperature‐programmed conditions using the actual, correlated values of ΔH 0 and ΔS 0 and their uncorrelated Monte Carlo counterparts, respectively. The uncorrelated ΔH 0 and ΔS 0 values caused the retention‐time range of the simulations’ second dimension to expand substantially beyond that in the GC×GC. Other simulations were developed using a restricted range of uncorrelated ΔH 0 and ΔS 0 values to mimic more closely the retention‐time range of the GC×GC's second dimension. The intervals between nearest neighbor retention‐time coordinates were calculated in both the latter simulations and the GC×GC. The intervals were larger in the simulations than in the GC×GC because the former contained uncorrelated coordinates and the latter contained correlated ones, which clustered along or near the diagonal. The retention times in the first dimension of the GC×GC were Poisson distributed, as assessed by statistical‐overlap theory. In contrast, the two‐dimensional reduced retention‐time coordinates in the GC×GC were not Poisson distributed, because retention times were correlated. However, the reduced retention‐time coordinates in the simulations were Poisson distributed.
Speciation of nitrogen‐containing compounds in diesel fuel by comprehensive two‐dimensional gas chromatography
Authors: Wang Frank Cheng‐Yu , Robbins Winston K. , Greaney Mark A. 
Published: March 2004

AbstractNitrogen‐containing compounds in diesel fuel have been speciated by comprehensive two‐dimensional gas chromatography with nitrogen chemiluminescence detector (GC×GC‐NCD). The speciation of nitrogen‐containing compounds in diesel is difficult because of low concentration and complexity. The advantages of GC×GC are improved resolution and enhanced sensitivity. GC×GC‐NCD can achieve the type and class separation of nitrogen‐containing compounds with an appropriate separation column combination. Diesel contains both neutral (indoles and carbazoles) and basic (pyridines and quinolines) nitrogen‐containing compounds. Relative concentrations of each class as well as each carbon number family can be quantified by integrating their peak volumes. This study demonstrates the capability of GC×GC‐NCD for speciation of nitrogen‐containing compound classes.