bluuebunny/crossref_metadata_2025_split huggingface dataset:
Proteomics of loosely bound cell wall proteins of Arabidopsis thaliana cell suspension cultures: A critical analysis
Authors: Borderies Gisèle , Jamet Elisabeth , Lafitte Claude , Rossignol Michel , Jauneau Alain , Boudart Georges , Monsarrat Bernard , Esquerré‐Tugayé Marie‐Thérèse , Boudet Alain , Pont‐Lezica Rafael 
Published: October 2003

AbstractThe complete sequencing of the Arabidopsis thaliana genome allows the use of the recently developed mass spectrometry techniques to identify the cell wall proteins (CWPs). Most proteomic approaches depend on the quality of sample preparation. Extraction of CWPs is particularly complex since the proteins may be free in the apoplast or are embedded in a polysaccharide matrix where they are retained by Van der Waals interactions, hydrogen bonds, hydrophobic or ionic interactions, or cross‐linked by covalent bonds. Specific and sequential extraction procedures thus need to be developed. We report on the sequential extraction of loosely bound CWPs from living A. thaliana cells in culture. Different salts and chelating agents were used for releasing the proteins from the wall. Their effects on the extraction of CWPs and on the integrity of the plasma membrane were evaluated. Bioinformatic software was used to identify proteins and to predict their sub‐cellular localization. The obtained data show that the plasma membrane of cells in culture was easily damaged by some steps of the extraction procedure, leading to the release of increasing amounts of intracellular proteins. Nevertheless, we identified fifty CWPs among which thirteen were new proteins for the cell wall. In addition, 76% of these CWPs were basic proteins not resolved in two‐dimensional (2‐D) gel electrophoresis. The existence of two hypothetical proteins was confirmed. The structure of three proteins could be confirmed using mass spectrometry data.
Thousandfold signal increase using field‐amplified sample stacking for on‐chip electrophoresis
Authors: Jung Byoungsok , Bharadwaj Rajiv , Santiago Juan G. 
Published: October 2003

AbstractField‐amplified sample stacking (FASS) leverages conductivity gradients between a volume of injected sample and the background buffer to increase sample concentration. A major challenge in applying FASS to on‐chip assays is the initial setup of high‐conductivity gradient boundaries in the region of the injected sample volume. We have designed, fabricated, and characterized a novel FASS‐capillary electrophoresis (CE) chip design that uses a photoinitiated porous polymer structure to facilitate sample injection and flow control for high‐gradient FASS. This polymer structure provides a region of high flow resistance that allows the electromigration of sample ions. We have demonstrated an electropherogram signal increase by a factor of 1100 in electrophoretic separations of fluorescein and Bodipy with, respectively, 2 μM and 1 μM initial concentrations.
Sequence‐dependent bending in plasmid pUC19
Authors: Stellwagen Nancy C. 
Published: October 2003

AbstractThe circular permutation assay has been used to characterize sequence‐dependent bending in plasmid pUC19 (2686 bp). Linear, permuted sequence isomers of pUC19 exhibit different mobilities in large‐pore polyacrylamide gels, suggesting that the plasmid contains two sequence‐dependent bends, one located at ∼ 806 bp, close to the start site of transcription, and the other at ∼ 2617 bp, near the promoter of the ampicillin resistance gene. The mobility patterns are independent of the buffer in which the gels are cast and run, independent of pH over the range 6.5–8.6, and independent of the presence or absence of various monovalent ions added to the buffer, suggesting that the maxima in the mobility patterns correspond to stable bends in the helix backbone, not anisometric flexibility. Although the mobility patterns are unchanged when Ba++ or Zn++ ions are added to the buffer, several of the sequence isomers exhibit multiple sharp sub‐bands in solutions containing Mg++ or Ca++ ions, indicating the presence of multiple conformational isomers. In addition, the mobility maximum near the start site of transcription is shifted by ∼ 100 bp in the presence of Ca++ ions, suggesting that the location of the actual bend center is somewhat variable, depending on the ionic composition of the surrounding medium. The number of maxima observed in the mobility pattern can be increased by adding a bend from another plasmid, such as Litmus 28; the number of maxima can be decreased by removing one of the bends in pUC19 by restriction enzyme digestion and religation. Hence, the number of maxima in the mobility pattern is an accurate indication of the number of stable, sequence‐dependent bends present in the plasmid. The combined results indicate that the circular permutation assay in large‐pore polyacrylamide gels is a reliable method of detecting and analyzing sequence‐dependent bends in kilobase‐sized DNA molecules.
Quantitative and qualitative measure of intralaboratory two‐dimensional protein gel reproducibility and the effects of sample preparation, sample load, and image analysis
Authors: Choe Leila H. , Lee Kelvin H. 
Published: October 2003

AbstractWe investigate one approach to assess the quantitative variability in two‐dimensional gel electrophoresis (2‐DE) separations based on gel‐to‐gel variability, sample preparation variability, sample load differences, and the effect of automation on image analysis. We observe that 95% of spots present in three out of four replicate gels exhibit less than a 0.52 coefficient of variation (CV) in fluorescent stain intensity (% volume) for a single sample run on multiple gels. When four parallel sample preparations are performed, this value increases to 0.57. We do not observe any significant change in quantitative value for an increase or decrease in sample load of 30% when using appropriate image analysis variables. Increasing use of automation, while necessary in modern 2‐DE experiments, does change the observed level of quantitative and qualitative variability among replicate gels. The number of spots that change qualitatively for a single sample run in parallel varies from a CV = 0.03 for fully manual analysis to CV = 0.20 for a fully automated analysis. We present a systematic method by which a single laboratory can measure gel‐to‐gel variability using only three gel runs.
Longer‐term implications of responsiveness to ‘thin‐ideal’ television: support for a cumulative hypothesis of body image disturbance?
Authors: Hargreaves Duane , Tiggemann Marika 
Published: October 2003

AbstractBrief exposure to thin‐ideal media images has been shown to have a small but consistent negative impact on women and girls' body dissatisfaction. The present study aimed to examine the consequence of these small changes in body dissatisfaction for the development of body image over time. A sample of 80 adolescents (mean age = 17.2 years) completed measures of body dissatisfaction, drive for thinness, and drive for muscularity. Two years earlier they had viewed either 20 appearance‐related television commercials (containing female thin ideals) or 20 non‐appearance commercials as part of an experimental study. For girls, initial body dissatisfaction change in response to viewing appearance commercials at time 1 predicted subsequent body dissatisfaction and drive for thinness 2 years later, above and beyond the variance predicted by initial body dissatisfaction. Similar results were observed for boys' drive for thinness but not for body dissatisfaction. Overall, these results are consistent with a cumulative hypothesis of media exposure and body image development. Copyright © 2003 John Wiley & Sons, Ltd and Eating Disorders Association.
Evaluation of adolescent body satisfaction and associated eating disorder pathology in two communities
Authors: Baranowksi Mandy J. , Jorga Jagoda , Djordjevic Ivana , Marinkovic Jelena , Hetherington Marion M. 
Published: October 2003

AbstractObjective:As Eastern European countries adopt Anglo‐American ideals of body size, it can be predicted that body dissatisfaction (a core feature of the eating disorders) will be similar to that observed in western cultures. The objective of the present investigation is to compare adolescent males and females in urban schools of two countries (Scotland and Yugoslavia) as part of an ongoing longitudinal study of BMI, body satisfaction, well‐being and eating pathology.Method:625 adolescents had their BMI recorded and completed a series of questionnaires measuring body satisfaction, depression, anxiety and eating pathology.Results:Significant differences emerged as a function of gender in both countries and as a function of country. Girls reported significantly higher levels of body dissatisfaction than boys and scored higher on measures of restrained eating. However, eating pathology, depression and anxiety were higher in the Scottish cohort in general, and in the Scottish girls in particular. Similarly, self‐esteem was lower in the Scottish cohort and was particularly low in the girls.Discussion:Overall, body dissatisfaction appears to be a normative experience despite normal weight status for girls in both countries. However, risk factors for developing eating disorders appear higher in the western cohort. Results from the longitudinal assessments will highlight whether this trend is maintained over time. Copyright © 2003 John Wiley & Sons, Ltd and Eating Disorders Association.
Measurement and data analysis methods for field‐scale wind erosion studies and model validation
Authors: Zobeck Ted M. , Sterk Geert , Funk Roger , Rajot Jean Louis , Stout John E. , Van Pelt R. Scott 
Published: October 2003

AbstractAccurate and reliable methods of measuring windblown sediment are needed to conﬁrm, validate, and improve erosion models, assess the intensity of aeolian processes and related damage, determine the source of pollutants, and for other applications. This paper outlines important principles to consider in conducting ﬁeld‐scale wind erosion studies and proposes strategies of ﬁeld data collection for use in model validation and development. Detailed discussions include consideration of ﬁeld characteristics, sediment sampling, and meteorological stations. The ﬁeld shape used in ﬁeld‐scale wind erosion research is generally a matter of preference and in many studies may not have practical signiﬁcance. Maintaining a clear non‐erodible boundary is necessary to accurately determine erosion fetch distance. A ﬁeld length of about 300 m may be needed in many situations to approach transport capacity for saltation ﬂux in bare agricultural ﬁelds. Field surface conditions affect the wind proﬁle and other processes such as sediment emission, transport, and deposition and soil erodibility. Knowledge of the temporal variation in surface conditions is necessary to understand aeolian processes. Temporal soil properties that impact aeolian processes include surface roughness, dry aggregate size distribution, dry aggregate stability, and crust characteristics. Use of a portable 2 tall anemometer tower should be considered to quantify variability of friction velocity and aerodynamic roughness caused by surface conditions in ﬁeld‐scale studies. The types of samplers used for sampling aeolian sediment will vary depending upon the type of sediment to be measured. The Big Spring Number Eight (BSNE) and Modiﬁed Wilson and Cooke (MWAC) samplers appear to be the most popular for ﬁeld studies of saltation. Suspension ﬂux may be measured with commercially available instruments after modiﬁcations are made to ensure isokinetic conditions at high wind speeds. Meteorological measurements should include wind speed and direction, air temperature, solar radiation, relative humidity, rain amount, soil temperature and moisture. Careful consideration of the climatic, sediment, and soil surface characteristics observed in future ﬁeld‐scale wind erosion studies will ensure maximum use of the data collected. Copyright © 2003 John Wiley & Sons, Ltd.
Wind and water erosion and transport in semi‐arid shrubland, grassland and forest ecosystems: quantifying dominance of horizontal wind‐driven transport
Authors: Breshears David D. , Whicker Jeffrey J. , Johansen Mathew P. , Pinder John E. 
Published: October 2003

AbstractSoil erosion is an important process in dryland ecosystems, yet measurements and comparisons of wind and water erosion within and among such ecosystems are lacking. Here we compare wind erosion and transport ﬁeld measurements with water erosion and transport from rainfall‐simulation for three different semi‐arid ecosystems: a shrubland near Carlsbad, New Mexico; a grassland near Denver, Colorado; and a forest near Los Alamos, New Mexico. In addition to comparing erosion loss from an area, we propose a framework for comparing horizontal mass transport of wind‐ and water‐driven materials as a metric for local soil redistribution. Median erosion rates from wind for vertical mass ﬂux measurements (g m−2 d−1) were 1·5 × 10−2 for the shrubland, 8·3 × 10−3 for the grassland, and 9·1 × 10−3 for the forest. Wind‐driven transport from horizontal mass ﬂux measurements was greatest in the shrubland (15·0 g m−2 d−1) followed by the grassland (1·5 g m−2 d−1) and the forest sites (0·17 g m−2 d−1). Annual projections accounting for longer‐term site meteorology suggest that wind erosion exceeds water erosion at the shrubland by c. 33 times and by c. ﬁve times at the forest, but not the grassland site, where the high clay content of the soils contributed to greater amounts of water erosion: water erosion exceeded wind erosion by about three times. Horizontal transport by wind was greater than that by water for all three systems, overwhelmingly so in the shrubland (factor of c. 2200). Our results, which include some of the only wind erosion measurements to date for semi‐arid grasslands and forests, provide a basis for hypothesizing trends in wind and water erosion among ecosystems, highlight the importance of wind erosion and transport in semi‐arid ecosystems, and have implications for land surface geomorphology, contaminant transport, and ecosystem biogeochemistry. Copyright © 2003 John Wiley & Sons, Ltd.
Accurate water delivery using a simplified automated farm turnout
Authors: Stringam Blair L. , Sauer Brian W. , Pugh Clifford A. 
Published: October 2003

AbstractA simplified automated farm turnout was designed to maintain constant turnout flowrates from canal delivery systems to individual farm fields. Off‐the‐shelf components were combined to fabricate this device. The cost of all the components totaled less than $2300. All of these components work together to maintain turnout flowrates to the specified amount plus or minus 3% error. These turnouts are recommended for canal systems where the canal levels typically fluctuate throughout the day. Four of these automated turnouts have been installed; three on farms near Boise, Idaho, and one in Yuma, Arizona. Copyright © 2003 John Wiley & Sons, Ltd.
A Markov chain simulation model for predicting critical wet and dry spells in Kenya: analysing rainfall events in the Kano Plains
Authors: Ochola W. O. , Kerkides P. 
Published: October 2003

AbstractThe occurrence of wet and dry spells is a phenomenon most often used to identify the arid and semi‐arid lands (ASAL) in Kenya. The use of first‐order Markov processes that are embedded into a computer model to determine the critical climate extremes is presented. The model uses the concepts of conditional probability, Poisson probability distribution function and chi‐square testing to predict the critical spells. The daily rainfall data (1981–2000) for two weather stations in the Kano Plains (Kenya) have been used to illustrate model application. For example, based upon the bimodal rainfall pattern in the study area, the model revealed the length of the critical dry spell to be 14 days in the long rainy season and 12 days in the short rainy season, while the critical wet spell was found to be 12 and 8 days, for the long and short rains respectively for Ahero Irrigation Scheme. It is recommended that a climate and environmental audit in the Kano Plains for the determination of land and water management strategies include critical dry and wet spell determination. This will enhance more sustainable planning and utilization of the crucial water and land resources in the region and in other tropical rangelands. There are possibilities of integrating the model with other agro‐ecosystems models and other natural resource management decision support systems. Copyright © 2003 John Wiley & Sons, Ltd.
Farm water and soil management for improved water use in the North China Plain
Authors: Pereira L. S. , Cai L. G. , Hann M. J. 
Published: October 2003

AbstractThe rapid development of industry and urban areas, population growth and rising living standards have all resulted in an increased water demand for non‐agricultural uses in the North China Plain, therefore decreasing the water availability for irrigation. Technologies that favour a reduced demand and water‐saving practices in irrigation are required to assure the sustainability of water use in agricultural production. This paper presents main research results relative to the integration of water and soil management technologies which may contribute to improving the use of water and land in agricultural production, reducing demand for irrigation, and more efficient use of groundwater. Improved estimates of crop irrigation requirements, better irrigation scheduling for the winter wheat crop and improved surface irrigation systems, result in water saving corresponding to about 100 mm in very dry years and up to 250 mm in average years with a small yield increase. These savings represent 16–33% of water use during the wheat crop season. Improvements in soil management lead to improved soil fertility and physical properties (including hydraulic conductivity). These improvements produce potential increases in summer maize yields of between 10 and 20%. Copyright © 2003 John Wiley & Sons, Ltd.
Effects of osteogenic protein‐1 (OP‐1, BMP‐7) on gene expression in cultured medial collateral ligament cells
Authors: Tsai Alicia D. , Yeh Lee‐Chuan C. , Lee John C. 
Published: October 2003

AbstractOsteogenic protein‐1 (OP‐1, also called BMP‐7), a member of the BMP family and the TGF‐β superfamily, induces formation of new bone and cartilage, but also regulates a wide array of processes. In the present study, the expression of several characteristic biochemical markers of ligaments, such as Six1, Scleraxis, aggrecan, and type I collagen in primary cultures of adult rat medial collateral ligament (MCL) cells was determined. The effects of OP‐1 on cell proliferation and on gene expression were subsequently examined. OP‐1 stimulated cell proliferation, alkaline phosphatase (AP) activity, and the steady‐state mRNA levels of the transcription factor Runx2/Cbfa1 in a dose‐ and time‐dependent manner. The mRNA levels of type I collagen only increased slightly, but the activity of the cloned collagen promoter increased by 2‐fold in transiently transfected MCL cells. OP‐1 also stimulated aggrecan mRNA expression. The mRNA levels of Six1 and Scleraxis were not detectably altered by OP‐1. In control cultures, the steady‐state mRNA levels of ActR‐I, BMPR‐IA, BMPR‐IB, and BMPR‐II increased as a function of time in culture. The mRNA levels of BMP‐1 and ‐4 increased significantly after 12 days, but those of BMP‐2 and ‐6 did not change. The GDF‐1, ‐3, ‐5, ‐6, and ‐8 mRNA levels in the control cultures also increased as a function of time. OP‐1 treatment stimulated mRNA expression of BMPR‐IA and BMPR‐II, but had little effect on ActR‐I and BMPR‐IB mRNA expression. OP‐1 lowered the BMP‐1, ‐2, and ‐6 mRNA levels without changing the BMP‐4 mRNA level. OP‐1 treatment also reduced the mRNA levels of GDFs detected. In summary, the present study demonstrated that OP‐1 stimulated cell proliferation and mRNA expression of several biochemical markers in this ligament cell culture model and established the spatial and temporal appearance of several members of the TGF‐β superfamily. © 2003 Wiley‐Liss, Inc.
Strong induction of p73 protein in vivo coincides with the onset of apoptosis in rat liver after treatment with the hepatocarcinogen N‐nitrosomorpholine (NNM)
Authors: Tudzarova‐Trajkovska Slavica , Wȩsierska‐Ga̧dek Józefa 
Published: October 2003

AbstractTreatment of rats with genotoxic hepatocarcinogens such as N‐nitrosomorpholine (NNM) causes severe hepatotoxicity associated with apoptosis of hepatocytes beginning after 12 h. Previously, we reported that after a single administration of high NNM dose p53 protein level increased in liver but not in testis and that the first wave of apoptosis preceded the induction of p53 indicating that apoptosis in liver was driven by a p53‐independent pathway. We now show a pronounced upregulation of p73 protein, a p53‐related gene product. The increase of p73 α and β occurred already 6 h after NNM administration and preceded the onset of apoptosis by 6 h. Very strong p73 signals appeared 20 and 40 h post‐treatment and persisted for a few days, whereas p53 was induced only transiently at 20 and 40 h post‐treatment. Immunohistochemical analysis revealed that unlike p53, p73 was detected in the nuclei of hepatocytes undergoing apoptosis. Following the upregulation of p73 levels, the products of several genes regulating DNA repair, e.g., GADD‐45 and p53R2 and mediating apoptosis such as apoptosis inducing factor (AIF) were rapidly induced, whereas transient elevation of MDM‐2 protein was delayed and coincided temporary with activation of p53 protein. Interestingly, NF‐κB another transcription factor responding to cellular stress was activated at 20 h after NNM administration and reached a maximum after an additional 20 h. Our data indicate that activated p73 protein may positively affect the induction and execution of apoptosis in response to genotoxic action of NNM. © 2003 Wiley‐Liss, Inc.
Differential regulation of protein expression, growth and apoptosis by natural and synthetic retinoids
Authors: Christine Pratt M.A. , Niu Minying , White Dawn 
Published: October 2003

AbstractAll‐transretinoic acid (ATRA) can down regulate the anti‐apoptotic protein Bcl‐2 and the cell cycle proteins cyclin D1 and cdk2 in estrogen receptor‐positive breast cancer cells. We show here that retinoids can also reduce expression of the inhibitor of apoptosis protein, survivin. Here we have compared the regulation of these proteins in MCF‐7 and ZR‐75 breast cancer cells by natural and synthetic retinoids selective for the RA receptors (RARs) α, β, and γ then correlated these with growth inhibition, induction of apoptosis and chemosensitization to Taxol. In both cell lines ATRA and 9‐cisRA induced the most profound decreases in cyclin D1 and cdk2 expression and also mediated the largest growth inhibition. The RARα agonist, Ro 40‐6055 also strongly downregulated these proteins although did not produce an equivalent decrease in S‐phase cells. Only ATRA induced RARβ expression. ATRA, 9‐cisRA and 4‐HPR initiated the highest level of apoptosis as determined by mitochondrial Bax translocation, while only ATRA and 9‐cisRA strongly reduced Bcl‐2 and survivin protein expression. Enumeration of dead cells over 96 h correlated well with downregulation of both survivin and Bcl‐2. Simultaneous retinoid‐mediated reduction of both these proteins also predicted optimal Taxol sensitization. 4‐HPR was much weaker than the natural retinoids with respect to Taxol sensitization, consistent with the proposed requirement for reduced Bcl‐2 in this synergy. Neither the extent of cell cycle protein regulation nor AP‐1 inhibition fully predicted the antiproliferative effect of the synthetic retinoids suggesting that growth inhibition requires regulation of a spectrum of RAR‐regulated gene products in addition even to pivotal cell cycle proteins. © 2003 Wiley‐Liss, Inc.