bluuebunny/crossref_metadata_2025_split huggingface dataset:
Stability of transgenes and presence of N6 methyladenine DNA in transformed wheat cells
Authors: Chen Dong Fang , Dale Philip J. , Heslop‐Harrison John S. , Snape John W. , Harwood Wendy , Bean Samantha , Mullineaux Philip M. 
Published: November 2004

SummaryA number of stably transformed wheat cell lines were obtained using two different direct gene transfer techniques. When integration of the foreign genes was investigated in DNA samples taken at 10 months post‐selection, complicated profiles of transgene bands were observed in Southern blot analysis. Among these, a number of common bands were identified showing similar hybridization patterns between independently transformed cell lines. This type of hybridization pattern has been a common observation and is usually interpreted as concatameric rearrangement of integrated DNA. However, when integration was reinvestigated with DNA samples taken at 30 months postselection, the hybridization pattern changed and most of the common bands had disappeared. Further analysis using a set of methylation‐sensitive enzymes revealed that the DNA represented by the common bands was N6‐adenine methylated (m6A DNA), and there was even m6A DNA in some 30 month samples. Although the source of m6A DNA in the wheat cultures was not clearly established, the data indicate that transformation of an endophyte (e.g. a mycoplasma‐like organism) may have occurred at the same time as the transformation of wheat cells. The integration pattern of undermethylated transgenes in the transformed cells became simpler and clearer after treating the DNA preparations with Dpnl, which only cuts m6A DNA. The implications of these data for other methods of inoculating cereals with DNA are discussed.
Asparaginase gene expression is regulated in a complex spatial and temporal pattern in nitrogen‐sink tissues
Authors: Grant Murray , Bevan Michael W. 
Published: November 2004

SummaryAsparagine is an important nitrogen transport compound in higher plants. Mobilized asparagine is deamidated by the enzyme asparaginase to aspartate and ammonia, which are major sources of organic nitrogen for plant growth and development. Little is known about the role of asparagine catabolism during plant development as the enzyme is difficult to assay, although it is known that asparaginase activity is located in tissues undergoing rapid growth and development, particularly in young leaves and developing seeds. In tobacco plants containing an asparaginase‐GUS gene fusion, GUS expression was specifically located in young developing tissues such as the apical meristem and expanding leaves. In mature plants, GUS activity was found predominantly in various tissues of the developing seed. In lupin, where up to 80% of the fixed nitrogen is exported as asparagine to the developing seed, GUS activity was also located in developing tissues such as the apical meristem, and in specific tissue types in the developing seed previously shown to contain asparaginase activity. All of the tissues in which asparaginase expression occurred have previously been shown to contain localized high levels of asparagine. This study therefore demonstrates an important role for transcriptional control of an asparaginase gene in regulating asparaginase levels in N‐sink tissues.
Phosphatase antagonist okadaic acid inhibits steady‐state K+ currents in guard cells of Vicia faba
Authors: Thiel Gerhard , Blatt Michael R. 
Published: November 2004

SummaryThe effects of protein phosphatase inhibitors on steady‐state K+ currents in the plasma membrane of Vicia faba guard cells were studied. Cells were impaled with double barrelled electrodes to monitor membrane voltage and K+ currents under voltage clamp. Okadaic acid (OA) (1 μM), a specific inhibitor of phosphatase 1 and 2A activity, blocks inward (lK+(in)) and outward (lK+(out)) rectifying K+ channels. Both currents decreased in parallel with a sigmoidal time course with 50% inhibition at about 8 min. With 0.2 μM OA inhibition became slower and more variable (4–34 min). Inhibition did not recover by washing cells ≤ 20 min in OA‐free solution. In five out of seven cells OA also induced a rise in the background conductance, which lagged behind the inhibition of K+ current. Both decaying lK*(out) and rising leak conductance caused a depolarization. OA‐induced inhibition of lK+(in) and lK+(out) was without a significant effect on the kinetics of voltage‐dependent current activation and deactivation. In an alternative approach, guard cells were loaded from the voltage recording pipette with the non‐specific phosphatase inhibitor naphthylphosphate. After an impalement of some minutes lK+(in) and lK+(out) were small or undetectable. In conclusion inward and outward K+ channels in guard cells have a common voltage‐independent mode of control which is sensitive to phosphatase inhibitors. The known specificity of OA points to a mode of action in which a net increase of protein phosphorylation through inhibition of phosphatase 1 and/or 2A activity blocks conductance of both, lK+(in) and l(out)
Simulating in‐plane fatigue damage in woven glass fibre‐reinforced composites subject to fully reversed cyclic loading
Authors: VAN PAEPEGEM W. , DEGRIECK J. 
Published: November 2004

ABSTRACTThe interest in using fibre‐reinforced composites in structural components is increasing. Some of these structural composites, such as wind turbine blades, aircraft components and torsion shafts are subject to fatigue loadings. It is widely accepted that fully reversed cyclic loading is the most adverse loading for fibre‐reinforced composites, but the modelling of the material behaviour under this loading condition is very difficult. In this paper, a damage model is presented for woven glass fibre‐reinforced composites subject to fully reversed cyclic loading. First fatigue experiments have been conducted in displacement‐controlled fully reversed bending and the stiffness degradation and damage patterns have been observed. Based on these experimental data, a damage model has been developed, which includes the in‐plane stress components and the degradation of the in‐plane elastic properties. The model has been implemented in a commercial finite‐element code and simulation of the successive stages in the fatigue life has been performed. The model has been validated for a plain woven glass fabric reinforced composite and simulated stiffness degradation, damage growth and damage distribution have been compared with experimental data.
Proteasome inhibitors suppress formation of polyglutamine‐induced nuclear inclusions in cultured postmitotic neurons
Authors: Kim Woo‐Yang , Horbinski Craig , Sigurdson Wade , Higgins Dennis 
Published: November 2004

AbstractAt least nine neurodegenerative disorders are caused by expansion of polyglutamine repeats in various genes. This expansion induces the formation of nuclear inclusions (NI) within various cell types. In this study, we developed a model for polyglutamine diseases using primary cultures of sympathetic neurons from the superior cervical ganglia of prenatal rat pups. Transfection with a plasmid encoding 127 glutamine repeats causes NI to develop in ∼70% of the sympathetic neurons within 6 days. In addition, it causes somatic atrophy and inhibits dendritic growth. The NIs contain ubiquitinated proteins and sequester the molecular chaperone heat shock protein 70 (Hsp70). We found that two specific proteasome inhibitors, lactacystin and CEP1612, suppress thezformation of polyglutamine‐induced NI. In addition, lactacystin treatment induced the removal of preexisting NI. Western blotting and immunocytochemistry revealed that lactacystin and CEP1612 strongly induce the expression of Hsp70, whereas less specific proteasome inhibitor such as N‐acetyl‐Leu‐Leu‐Norleucinal does not. Coexpression of 127 glutamines with a plasmid encoding wild‐type Hsp70 gene resulted in a marked reduction of the percentage of neurons containing NI. In addition, transfection with plasmids encoding mutant Hsp70 blocked the effects of lactacystin. These findings further implicate Hsp70 as a neuroprotective molecule and they suggest the potential utility of certain proteasome inhibitors in the treatment of polyglutamine diseases.
Identification of regulatory cis‐acting elements for alternative splicing of presenilin 2 exon 5 under hypoxic stress conditions
Authors: Higashide Satoshi , Morikawa Keisuke , Okumura Masayo , Kondo Shinichi , Ogata Maiko , Murakami Tomohiko , Yamashita Akinori , Kanemoto Soshi , Manabe Takayuki , Imaizumi Kazunori 
Published: November 2004

AbstractAn alternatively spliced form of the presenilin 2 (PS2) gene lacking exon 5 (PS2V) was found in human brains with sporadic Alzheimer's disease. PS2V was induced by hypoxic stress in human neuroblastoma SK‐N‐SH cells, indicating that hypoxic stress affects the splicing machineries for PS2 exon 5. Here, we identified the critical cis‐acting element (sec 2) on the PS2 pre‐mRNA responsible for the aberrant splicing of PS2 exon 5 under hypoxic stress conditions. The element was composed of 23 nucleotides in exon 5 and RNA structural analyses showed a stem‐loop structure in this sequence. Treatment with an antisense oligonucleotide directed toward the cis‐acting element caused an increase in exon 5 inclusion. These results indicate that the sec 2 identified in this study is a novel regulatory element for exon 5 splicing under stress conditions and that trans‐acting factors could specifically bind to the element to skip exon 5 of PS2.
Opposite regulation of the mitochondrial apoptotic pathway by C2‐ceramide and PACAP through a MAP‐kinase‐dependent mechanism in cerebellar granule cells
Authors: Falluel‐Morel Anthony , Aubert Nicolas , Vaudry David , Basille Magali , Fontaine Marc , Fournier Alain , Vaudry Hubert , Gonzalez Bruno J. 
Published: November 2004

AbstractThe sphingomyelin‐derived messenger ceramides provoke neuronal apoptosis through caspase‐3 activation, while the neuropeptide pituitary adenylate cyclase‐activating polypeptide (PACAP) promotes neuronal survival and inhibits caspase‐3 activity. However, the mechanisms leading to the opposite regulation of caspase‐3 by C2‐ceramide and PACAP are currently unknown. Here, we show that PACAP prevents C2‐ceramide‐induced inhibition of mitochondrial potential and C2‐ceramide‐evoked cytochrome c release. C2‐ceramide stimulated Bax expression, but had no effect on Bcl‐2, while PACAP abrogated the action of C2‐ceramide on Bax and stimulated Bcl‐2 expression. The effects of C2‐ceramide and PACAP on Bax and Bcl‐2 were blocked, respectively, by the JNK inhibitor L‐JNKI1 and the MEK inhibitor U0126. L‐JNKI1 prevented the alteration of mitochondria induced by C2‐ceramide while U0126 suppressed the protective effect of PACAP against the deleterious action of C2‐ceramide on mitochondrial potential. Moreover, L‐JNKI1 inhibited the stimulatory effect of C2‐ceramide on caspase‐9 and ‐3 and prevented C2‐ceramide‐induced cell death. U0126 blocked PACAP‐induced Bcl‐2 expression, abrogated the inhibitory effect of PACAP on ceramide‐induced caspase‐9 activity, and promoted granule cell death. The present study reveals that C2‐ceramide and PACAP exert opposite effects on Bax and Bcl‐2 through, respectively, JNK‐ and ERK‐dependent mechanisms. These data indicate that the mitochondrial pathway plays a pivotal role in the pro‐ and anti‐apoptotic effects of C2‐ceramide and PACAP.
Lower All‐Cause, Cardiovascular, and Cancer Mortality in Centenarians' Offspring
Authors: Terry Dellara F. , Wilcox Marsha A. , McCormick Maegan A. , Pennington JaeMi Y. , Schoenhofen Emily A. , Andersen Stacy L. , Perls Thomas T. 
Published: November 2004

Objectives: To assess the cause of death for centenarians' offspring and controls.Design: Cross‐sectional study.Setting: Community‐based, nationwide sample.Participants: Family pedigree information was collected on 295 offspring of centenarians (from 106 families with a parent already enrolled in the nationwide New England Centenarian Study) and on 276 controls (from 82 control families) from 1997 to 2000. Controls were individuals whose parents were born in the same year as the centenarians but at least one of whom died at the average life expectancy.Measurements: Age at death and cause of death.Results: Centenarians' offspring had a 62% lower risk of all‐cause mortality (P<.001), a 71% lower risk of cancer‐specific mortality (P=.002), and an 85% lower risk of coronary heart disease–specific mortality (P<.001). Significant differences were not found for other causes of death. However of those who died centenarian offsprings dead at a significantly younger age than controls.Conclusion: These findings suggest that centenarians' offspring have lower all‐cause mortality rates and cause‐specific mortality rates for cancer and coronary heart disease. These results suggest that mechanisms for survival to exceptional old age may go beyond the avoidance or delay of cardiovascular disease and also include the avoidance or delay of cancer. Moreover survival advantage of centenarian offsprings may not be due to factors related to childhood mortality. Ultimately, survival to exceptional old age may involve lower susceptibility to a broad range of age‐related diseases, perhaps secondary to inhibition of basic mechanisms of aging.
Using the Minimum Data Set to Select Nursing Home Residents for Interview About Pain
Authors: Chu Lily , Schnelle John F. , Cadogan Mary P. , Simmons Sandra F. 
Published: November 2004

Objectives: To determine how many nursing home residents can provide stable responses to a simple pain interview and whether a Minimum Data Set (MDS) cognitive performance measure can be used to identify these residents.Design: Cross‐sectional descriptive study.Setting: Thirty‐three community‐based nursing homes.Participants: Eight hundred ninety‐five nursing home residents.Measurements: Resident completion rate, stability, and interrater reliability of a four‐item interview derived from the Geriatric Pain Measure were calculated. Demographic data and MDS items concerning pain and memory were obtained from medical records.Results: Overall, 835 residents were able to answer all four interview questions. At the lowest MDS recall score of 0, 52.7% of residents were able to complete all questions. All residents able to respond to the interview achieved high stability (kappa=0.633, P<.001). Overall, 62.8% of residents with daily pain or activity‐limiting pain on interview did not have daily or moderate to severe pain recorded on the MDS. Residents who had lower MDS recall scores were significantly less likely (P=.004) to be appropriately identified on the MDS.Conclusion: Residents with a low MDS recall score were significantly less likely to be noted on the MDS as having serious pain despite being able to complete a simple yes/no interview about pain in a stable fashion. Nursing staff should attempt to ask all residents direct questions about pain. Surveyors may restrict direct questioning to those residents with an MDS recall score of 1 or higher if time is an important consideration. Adjustment for MDS‐derived prevalence of pain based on residents' cognitive status is questionable.
Persistent Pain in Frail Older Adults After Hip Fracture Repair
Authors: Herrick Cynthia , Steger‐May Karen , Sinacore David R. , Brown Marybeth , Schechtman Kenneth B. , Binder Ellen F. 
Published: November 2004

Objectives: To identify factors associated with persistent hip pain in elderly hip fracture patients with physical frailty.Design: Cohort study.Setting: Community‐based study conducted at academic medical center.Participants: Eighty‐eight men and women (mean age±standard deviation 80±7 years) with a recent hip fracture (mean 14.5±4.8 weeks after hip fracture repair) and physical frailty, defined as a modified Physical Performance Test Score between 12 and 28, enrolled in an exercise intervention trial.Measurements: Dependent variable was self‐report of moderate to severe regional hip pain in the week preceding the baseline interview. Independent variables were self‐reported demographic information, health characteristics, and activity of daily living (ADL) function; Yesavage Mood Score (YMS); 36‐item Short Form percentile scores; and objective measurements of lower extremity strength, range of motion, balance, and gait.Results: Forty‐two percent of the sample reported moderate or severe hip pain at the baseline assessment. Moderate/severe pain was related to difficulty with ADL performance and multiple measures of quality of life. Variables independently associated with moderate/severe hip pain were frequency of pain medication use (adjusted odds ratio (AOR)=5.75, 95% confidence interval (CI)=2.23–14.82, P=.003), YMS score (AOR=2.69, 95% CI=1.18–6.12, P=.02), and knee extension at 60°/s in the fractured limb (AOR=0.96, 95% CI=0.92–1.0, P=.05, model coefficient of determination=0.34).Conclusion: Persistent hip pain is a frequent symptom in frail elderly community‐dwelling hip fracture patients. Pain medication use, symptoms of depression, and skeletal muscle weakness of the fractured leg are independent correlates of moderate to severe hip pain in this patient population. Clinicians should assess for, and address, persistent pain in this patient population.
Self‐Reported Delay in Seeking Care Has Poor Validity for Predicting Adverse Outcomes
Authors: Rupper Randall W. , Konrad Thomas R. , Garrett Joanne M. , Miller William , Blazer Dan G. 
Published: November 2004

Objectives: To determine whether self‐reports of delayed care predict increased mortality and functional decline in community‐dwelling elderly.Design: Longitudinal cohort study.Setting: Five counties in North Carolina.Participants: A total of 4,162 randomly sampled individuals aged 65 and older.Measurements: The primary outcome was the proportional hazard ratio (HR) for death in cohorts stratified by self‐reports of delayed or foregone care. A secondary outcome, functional decline, measured the cohorts' odds of developing increased dependency in activities of daily living (ADLs). Control variables included predisposing, enabling, and need factors.Results: Of 3,964 eligible participants reporting, 61% never, 27% once in a while, and 12% quite often delayed care. Over 3 years, 13% of participants died, and 17% developed increased ADL dependency. Nevertheless, in unadjusted and adjusted models, neither 3‐year mortality HRs nor the odds of functional decline differed between cohorts reporting varying degrees of delayed care. Survival probabilities remained higher for 15 years among those reporting delaying care often.Conclusion: The inability of self‐reported delay to predict adverse outcomes in community‐dwelling elderly suggests the need for better understanding and support of the care‐seeking process and additional measures of timeliness of access.
The effects of particulate air pollution on daily deaths: a multi-city case crossover analysis
Authors: Schwartz J 
Published: November 2004

Background:Numerous studies have reported that day-to-day changes in particulate air pollution are associated with day-to-day changes in deaths. Recently, several reports have indicated that the software used to control for season and weather in some of these studies had deficiencies.Aims:To investigate the use of the case-crossover design as an alternative.Methods:This approach compares the exposure of each case to their exposure on a nearby day, when they did not die. Hence it controls for seasonal patterns and for all slowly varying covariates (age, smoking, etc) by matching rather than complex modelling. A key feature is that temperature can also be controlled by matching. This approach was applied to a study of 14 US cities. Weather and day of the week were controlled for in the regression.Results:A 10 μg/m3increase in PM10was associated with a 0.36% increase in daily deaths from internal causes (95% CI 0.22% to 0.50%). Results were little changed if, instead of symmetrical sampling of control days the time stratified method was applied, when control days were matched on temperature, or when more lags of winter time temperatures were used. Similar results were found using a Poisson regression, but the case-crossover method has the advantage of simplicity in modelling, and of combining matched strata across multiple locations in a single stage analysis.Conclusions:Despite the considerable differences in analytical design, the previously reported associations of particles with mortality persisted in this study. The association appeared quite linear. Case-crossover designs represent an attractive method to control for season and weather by matching.
MASSLESS FLOWS I: THE SINE-GORDON AND O(n) MODELS
Authors: FENDLEY P. , SALEUR H. , ZAMOLODCHIKOV AL. B. 
Published: November 2004

The massless flow between successive minimal models of conformal field theory is related to a flow within the sine-Gordon model when the coefficient of the cosine potential is imaginary. This flow is studied, partly numerically, from three different points of view. First we work out the expansion close to the Kosterlitz-Thouless point, and obtain roaming behavior, with the central charge going up and down in between the UV and IR values of c=1. Next we analytically continue the Casimir energy of the massive flow (i.e. with real cosine term). Finally we consider the lattice regularization provided by the O(n) model in which massive and massless flows correspond to high- and low-temperature phases. A detailed discussion of the case n=0 is then given using the underlying N=2 supersymmetry, which is spontaneously broken in the low-temperature phase. The “index” tr F(−1)F follows from the Painlevé III differential equation, and is shown to have simple poles in this phase. These poles are interpreted as occurring from level crossing (one-dimensional phase transitions for polymers). As an application, new exact results for the connectivity constants of polymer graphs on cylinders are obtained. These results and points of view are used in the following paper to discuss the appropriate exact S matrices and the resulting Casimir energies.
SPEECH-TO-TEXT CONVERSION IN FRENCH
Authors: GAUVAIN J.L. , LAMEL L.F. , ADDA G. , MARIANI J. 
Published: November 2004

Speech-to-text conversion of French necessitates that both the acoustic level recognition and language modeling be tailored to the French language. Work in this area was initiated at LIMSI over 10 years ago. In this paper a summary of the ongoing research in this direction is presented. Included are studies on distributional properties of French text materials; problems specific to speech-to-text conversion particular of French; studies in phoneme-to-grapheme conversion for continuous, error-free phonemic strings; past work on isolated-word speech-to-text conversion; and more recent work on continuous-speech, speech-to-text conversion. Also demonstrated is the use of phone recognition for both language and speaker identification. The continuous speech-to-text conversion for French is based on a speaker-independent, vocabulary-independent recognizer. In this paper phone recognition and word recognition results are reported evaluating this recognizer on read speech taken from the BREF corpus. The recognizer was trained on over 4 hours of speech from 57 speakers, and tested on sentences from an independent set of 19 speakers. A phone accuracy of 78.7% was obtained using a set of 35 phones. The word accuracy was 88% for a 1139 word lexicon and 86% for a 2716 word lexicon, with a word pair grammar with respective perplexities of 100 and 160. Using a bigram grammar, word accuracies of 85.5% and 81.7% were obtained with 5 K and 20 K word vocabularies, with respective perplexities of 122 and 205.