bluuebunny/crossref_metadata_2025_split huggingface dataset:
Bidirectional interactions between the circadian and reward systems: is restricted food access a unique zeitgeber?
Authors: Webb Ian C. , Baltazar Ricardo M. , Lehman Michael N. , Coolen Lique M. 
Published: October 2009

AbstractReward is mediated by a distributed series of midbrain and basal forebrain structures collectively referred to as the brain reward system. Recent evidence indicates that an additional regulatory system, the circadian system, can modulate reward‐related learning. Diurnal or circadian changes in drug self‐administration, responsiveness to drugs of abuse and reward to natural stimuli have been reported. These variations are associated with daily rhythms in mesolimbic electrical activity, dopamine synthesis and metabolism, and local clock gene oscillations. Conversely, the presentation of rewards appears capable of influencing circadian timing. Rodents can anticipate a daily mealtime by the entrainment of a series of oscillators that are anatomically distinct from the suprachiasmatic nucleus. Other work has indicated that restricted access to non‐nutritive reinforcers (e.g. drugs of abuse, sex) or to palatable food in the absence of an energy deficit is capable of inducing relatively weak anticipatory activity, suggesting that reward alone is sufficient to induce anticipation. Recent attempts to elucidate the neural correlates of anticipation have revealed that both restricted feeding and restricted palatable food access can entrain clock gene expression in many reward‐related corticolimbic structures. By contrast, restricted feeding alone can induce or entrain clock gene expression in hypothalamic nuclei involved in energy homeostasis. Thus, under ad libitum feeding conditions, the weak anticipatory activity induced by restricted reward presentation may result from the entrainment of reward‐associated corticolimbic structures. The additional induction or entrainment of oscillators in hypothalamic regulatory areas may contribute to the more robust anticipatory activity associated with restricted feeding schedules.
Thalamo‐cortical processing of near‐threshold somatosensory stimuli in humans
Authors: Klostermann Fabian , Wahl Michael , Schomann Jesko , Kupsch Andreas , Curio Gabriel , Marzinzik Frank 
Published: October 2009

AbstractSomatosensory stimuli elicit complex cortical responses that are discernible as somatosensory evoked potentials (SEPs) in scalp electroencephalographic recordings. Whereas earlier SEP components, occurring up to 100 ms after stimulus delivery, have been labeled ‘preconscious’, later responses have been associated with stimulus awareness. To date, how far these processes are primarily cortical or comprise additional subcortical operations remains open. Therefore, we recorded thalamic and scalp SEPs evoked by perceived as well as unperceived median nerve stimulation in neurosurgical patients with electrodes implanted into the ventral intermediate nucleus of the thalamus for deep brain stimulation. At stimulation intensities below perceptual threshold, only thalamic SEP components appeared consistently during the first 75 ms after stimulus delivery. Stimulation that was perceived by the patients elicited cortical as well as thalamic SEPs that lasted longer than 75 ms. These results indicate that the thalamus remains active after the primary propagation of a sensory signal to the cortex, and suggest that the transition from elementary to higher‐order somatosensory processing is based on thalamo‐cortical interactions.
Resources drive trade‐off between viral lifestyles in the plankton: evidence from freshwater microbial microcosms
Authors: Pradeep Ram A. S. , Sime‐Ngando T. 
Published: October 2009

SummaryViruses have evolved different life strategies for coping with environmental challenges and this is a key explanation for their omnipresence in aquatic systems. However, factors that determine the balance between lytic versus lysogenic decision within natural virioplankton are poorly documented, primarily in freshwaters. This study was designed to investigate the experimental short‐term (24 h incubation) effects of added organic and inorganic nutrients on the two viral lifestyles in nutrient‐depleted freshwater microbial (i.e. < 0.8 μm fraction) microcosms, using mitomycin C as prophage inductor agent. In the absence of mitomycin, viral lytic production increased as a functional response to the strong stimulation of bacterial growth rates (0.7–0.8 day−1) by the added nutrients, primarily the organic nutrients which appeared scarcer than inorganic nutrients and was related to the sampling period and the geomorphological peculiarities of Lake Pavin. In the presence of mitomycin, temperate phage production (frequency of lysogenically infected bacterial cells, FLC = 17–19% of total cells) significantly exceeded lytic production (frequency of lytically infected bacterial cells, FIC = 9–11%) in natural samples (i.e. without nutrient additions) as a result of enhanced prophage induction, which relatively increased with the decreasing contact probability between viruses and their potential hosts. In contrast, addition of nutrients drastically reduced FLC (< 4%) and increased FIC (> 22%). Both variables were antagonistically correlated as was the correlation between FLC and bacterial growth rates, supporting the idea that lysogeny may represent a maintenance strategy for viruses in harsh nutrient/host conditions which appeared as major instigators of the trade‐off between the two viral lifestyles. Overall, at the community level, we reject the hypothesis that nutrients but mitomicyn C stimulate temperate phage induction, and retained the hypotheses that nutrients rather (i) stimulate lytic viruses via enhanced host growth and (ii) when limiting, promote lysogenic conversion in natural waters.
Weight loss interventions in young people (18 to 25 year olds): a systematic review
Authors: Poobalan A. S. , Aucott L. S. , Precious E. , Crombie I. K. , Smith W. C. S. 
Published: October 2009

SummaryThis systematic review assesses weight loss interventions in young adults (18–25 years), who are vulnerable to weight gain. This age group experience critical life course points (leaving home for higher studies or job, pregnancy, cohabitation) and develop/establish lifestyle and behavioural patterns making this an opportune intervention period. Medline, Embase, Cinahl, PsychINFO and Cochrane Library were searched (1980 to March 2008). All trials and cohort studies with control groups that assessed weight loss interventions in this specific age group were included finally identifying 14 studies. Before and after comparison of behavioural/motivational interventions (−2.40 kg; 95% CI −5.4 to 0.6) and combination interventions (−2.96; 95% CI −4.4 to −1.5) consistently showed weight loss. Behavioural/motivational interventions increased self‐efficacy, the desire to control weight, boosted self‐esteem, and increased satisfaction with body areas and appearance. Interventions also showed improvements in HDL cholesterol, insulin, glucose and maximum oxygen uptake. However, recruitment to participation in interventions was a barrier for this age group with small sample sizes and short‐term interventions. There may be gender differences in preference to participation in certain type of interventions. Further research to understand attitudes towards healthy lifestyle and preferences of interventions is needed to develop suitable interventions for this vulnerable age group.
ESTIMATING A PARAMETER WHEN IT IS KNOWN THAT THE PARAMETER EXCEEDS A GIVEN VALUE
Authors: Gordon Ian R. , Hall Peter 
Published: October 2009

SummaryIn some statistical problems a degree of explicit, prior information is available about the value taken by the parameter of interest, θ say, although the information is much less than would be needed to place a prior density on the parameter's distribution. Often the prior information takes the form of a simple bound, ‘θ > θ1’ or ‘θ < θ1’, where θ1 is determined by physical considerations or mathematical theory, such as positivity of a variance. A conventional approach to accommodating the requirement that θ > θ1 is to replace an estimator, , of θ by the maximum of  and θ1. However, this technique is generally inadequate. For one thing, it does not respect the strictness of the inequality θ > θ1, which can be critical in interpreting results. For another, it produces an estimator that does not respond in a natural way to perturbations of the data. In this paper we suggest an alternative approach, in which bootstrap aggregation, or bagging, is used to overcome these difficulties. Bagging gives estimators that, when subjected to the constraint θ > θ1, strictly exceed θ1 except in extreme settings in which the empirical evidence strongly contradicts the constraint. Bagging also reduces estimator variability in the important case for which  is close to θ1, and more generally produces estimators that respect the constraint in a smooth, realistic fashion.
THE USE OF AGGREGATE DATA TO ESTIMATE GOMPERTZ‐TYPE OLD‐AGE MORTALITY IN HETEROGENEOUS POPULATIONS
Authors: Heathcote Christopher R. , Puza Borek D. , Roberts Steven P. 
Published: October 2009

SummaryWe consider two related aspects of the study of old‐age mortality. One is the estimation of a parameterized hazard function from grouped data, and the other is its possible deceleration at extreme old age owing to heterogeneity described by a mixture of distinct sub‐populations. The first is treated by half of a logistic transform, which is known to be free of discretization bias at older ages, and also preserves the increasing slope of the log hazard in the Gompertz case. It is assumed that data are available in the form published by official statistical agencies, that is, as aggregated frequencies in discrete time. Local polynomial modelling and weighted least squares are applied to cause‐of‐death mortality counts. The second, related, problem is to discover what conditions are necessary for population mortality to exhibit deceleration for a mixture of Gompertz sub‐populations. The general problem remains open but, in the case of three groups, we demonstrate that heterogeneity may be such that it is possible for a population to show decelerating mortality and then return to a Gompertz‐like increase at a later age. This implies that there are situations, depending on the extent of heterogeneity, in which there is at least one age interval in which the hazard function decreases before increasing again.
CLONING DATA: GENERATING DATASETS WITH EXACTLY THE SAME MULTIPLE LINEAR REGRESSION FIT
Authors: Haslett S. J. , Govindaraju K. 
Published: October 2009

SummaryThis paper presents a simple computational procedure for generating ‘matching’ or ‘cloning’ datasets so that they have exactly the same fitted multiple linear regression equation. The method is simple to implement and provides an alternative to generating datasets under an assumed model. The advantage is that, unlike the case for the straight model‐based alternative, parameter estimates from the original data and the generated data do not include any model error. This distinction suggests that ‘same fit’ procedures may provide a general and useful alternative to model‐based procedures, and have a wide range of applications. For example, as well as being useful for teaching, cloned datasets can provide a model‐free way of confidentializing data.
Frontal‐lobe mediated behavioral dysfunction in amyotrophic lateral sclerosis
Authors: Witgert M. , Salamone A. R. , Strutt A. M. , Jawaid A. , Massman P. J. , Bradshaw M. , Mosnik D. , Appel S. H. , Schulz P. E. 
Published: October 2009

Background:  Cognitive impairment secondary to frontal lobe atrophy exists in 40–60% of Amyotrophic Lateral Sclerosis (ALS) cases. We aimed to determine the prevalence of frontal‐lobe mediated behavioral impairment in (ALS) and to ascertain its relationship to cognitive impairment.Methods:  Two‐hundred and twenty five patients diagnosed with sporadic ALS were evaluated for behavioral dysfunction using the Frontal Systems Behavior Scale (FrSBe), a validated measure used to examine frontal‐lobe mediated behaviors, specifically apathy, executive dysfunction and disinhibition; a total behavior score is also provided. Additionally, a subset of patients also underwent a comprehensive neuropsychological evaluation.Results:  Changes in the total FrSBe scores were observed in 24.4% of the patients and 39.6% of the patients had impairment in at least one behavioral domain with symptoms of Apathy being the most common (31.1%). Cognitively impaired ALS patients had worse total (P = 0.05) and apathy scores (P < 0.01); however, behavioral dysfunction was also present in 16% of the cognitively intact patients. Half of the behaviorally intact patients exhibited cognitive impairment. Significant correlations were observed for performance on certain neuropsychological tests (Animal fluency, Block Design, Logical Memory I and Verbal Series Attention Test) and severity of behavioral dysfunction on certain FrSBe sub scores.Conclusions:  Frontal‐lobe mediated behavioral dysfunction appears to be common in ALS. Cognitively impaired ALS patients had greater behavioral dysfunction. Recognition of behavioral and cognitive dysfunction may assist health‐care providers and care‐givers recognize changes in decision‐making capacity and treatment compliance of patients with ALS.
High prevalence of bacterial vaginosis in adolescent girls in a tropical area of Ecuador
Authors: Vaca M , Guadalupe I , Erazo S , Tinizaray K , Chico ME , Cooper PJ , Hay P 
Published: October 2009

Please cite this paper as: Vaca M, Guadalupe I, Erazo S, Tinizaray K, Chico M, Cooper P, Hay P. High prevalence of bacterial vaginosis in adolescent girls in a tropical area of Ecuador. BJOG 2010;117:225–228.Bacterial vaginosis (BV) is a common clinical syndrome, but data are scarce on the BV prevalence in tropical regions among sexually active and virgin adolescents. To estimate the prevalence of BV among adolescent girls in an Ecuadorian coastal town, girls were asked to complete a questionnaire on risk factors for BV and vaginal samples were examined. Bacterial vaginosis was present in 31.5% of 213 girls, and the prevalence was similar in self‐reported virgin and sexually active girls (OR 1.06, 95% CI, 0.51–2.21, P = 0.88), although the power of this analysis was limited. The prevalence of BV was high among Ecuadorian adolescent girls, and did not appear to be associated with sexual activity.
Reasons for not seeking medical help for severe pelvic floor symptoms: a qualitative study in survivors of gynaecological cancer
Authors: Hazewinkel MH , Sprangers MAG , Taminiau‐Bloem EF , van der Velden J , Burger MPM , Roovers J‐PWR 
Published: October 2009

Objective  (1) To explore the reasons for not seeking help for severe pelvic floor symptoms after gynaecological cancer treatment. (2) To determine the willingness to undergo treatment for these symptoms. (3) To invite suggestions to improve outpatient care.Design  Qualitative study using semistructured interviews.Setting  Vulvar, endometrial or cervical cancer survivors treated in the Academic Medical Centre, Amsterdam, the Netherlands between1997 and 2007.Population  Purposively selected sample from 138 eligible respondents to pelvic floor‐related questionnaires, who were severely bothered by their symptoms (>75th percentile of domain sum score of questionnaires) and had not sought medical help.Methods  After each semistructured interview, a checklist with reasons for not seeking help was complemented with newly mentioned reasons. The interviews were stopped when data saturation was accomplished, i.e. three consecutive interviewees had not revealed new reasons. The interviews were analysed by two researchers independently.Main outcome measure  Help‐seeking behaviour for bothersome pelvic floor symptoms.Results  Fifteen interviews were conducted. Most reported reasons for not seeking help were that women found their symptoms bearable in the light of their cancer diagnosis and lacked knowledge about possible treatments. Seven women were willing to undergo treatment. Eleven women stated that care should be improved, specifically by timely referral to pelvic floor specialists and additional care by oncology nurses.Conclusions  There is a need for standardised attention to adverse effects on pelvic floor function after cancer treatment. This could be realised by quantifying symptoms using questionnaires, standardised attention for such symptoms by gynaecological oncologists or oncology nurses, and timely referral to pelvic floor specialists of women with bothersome pelvic floor symptoms.
Myelin protein composition is altered in mice lacking either sulfated or both sulfated and non‐sulfated galactolipids
Authors: Fewou Simon Ngamli , Fernandes Alda , Stockdale Katie , Francone Victor P. , Dupree Jeffrey L. , Rosenbluth Jack , Pfeiffer Steven E. , Bansal Rashmi 
Published: October 2009

J. Neurochem. (2010) 112, 599–610.AbstractMyelin is highly enriched in galactocerebroside (GalCer) and its sulfated form sulfatide. Mice, unable to synthesize GalCer and sulfatide (CGTnull) or sulfatide alone (CSTnull), exhibit disorganized paranodal structures and progressive dysmyelination. To obtain insights into the molecular mechanisms underlying these defects, we examined myelin composition of these mutants by two‐dimensional differential fluorescence intensity gel electrophoresis proteomic approach and immunoblotting. We identified several proteins whose expressions were significantly altered in these mutants. These proteins are known to regulate cytoskeletal dynamics, energy metabolism, vesicular trafficking or adhesion, suggesting a disruption in these physiological processes in the absence of myelin galactolipids. Further analysis of one of these proteins, nucleotide diphosphate kinase (NDK)/Nm23, showed that it was reduced in myelin of CGTnull and increased in CSTnull, but not in whole brain homogenate. Immunostaining showed an increase in its expression in the cell bodies of CGTnull‐ and a decrease in CSTnull‐oligodenrocytes, together leading to the hypothesis that transport of NDK/Nm23 from oligodenrocyte cell bodies into myelin may be differentially dysregulated in the absence of these galactolipids. This study provides new insights into the changes that occur in the composition/distribution of myelin proteins in mice lacking either unsulfated and/or sulfated galactolipids and reinforces the role of these lipids in intracellular trafficking.
The Value of Specialty Oncology Drugs
Authors: Goldman Dana P. , Jena Anupam B. , Lakdawalla Darius N. , Malin Jennifer L. , Malkin Jesse D. , Sun Eric 
Published: October 2009

Objective. To estimate patients' elasticity of demand, willingness to pay, and consumer surplus for five high‐cost specialty medications treating metastatic disease or hematologic malignancies.Data Source/Study Setting. Claims data from 71 private health plans from 1997 to 2005.Study Design. This is a revealed preference analysis of the demand for specialty drugs among cancer patients. We exploit differences in plan generosity to examine how utilization of specialty oncology drugs varies with patient out‐of‐pocket costs.Data Collection/Extraction Methods. We extracted key variables from administrative health insurance claims records.Principal Findings. A 25 percent reduction in out‐of‐pocket costs leads to a 5 percent increase in the probability that a patient initiates specialty cancer drug therapy. Among patients who initiate, a 25 percent reduction in out‐of‐pocket costs reduces the number of treatments (claims) by 1–3 percent, depending on the drug. On average, the value of these drugs to patients who use them is about four times the total cost paid by the patient and his or her insurer, although this ratio may be lower for oral specialty therapies.Conclusions. The decision to initiate therapy with specialty oncology drugs is responsive to price, but not highly so. Among patients who initiate therapy, the amount of treatment is equally responsive. The drugs we examine are highly valued by patients in excess of their total costs, although oral agents warrant further scrutiny as copayments increase.
Cytoprotective effects of adenosine and inosine in anin vitromodel of acute tubular necrosis
Authors: Módis Katalin , Gerő Domokos , Nagy Nóra , Szoleczky Petra , Tóth Zoltán Dóri , Szabó Csaba 
Published: October 2009

Background and purpose: We have established anin vitromodel of acute tubular necrosis in rat kidney tubular cells, using combined oxygen‐glucose deprivation (COGD) and screened a library of 1280 pharmacologically active compounds for cytoprotective effects.Experimental approach: We usedin vitrocell‐based, high throughput, screening, with cells subjected to COGD using hypoxia chambers, followed by re‐oxygenation. The 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide (MTT) and the Alamar Blue assay measured mitochondrial respiration and the lactate dehydrogenase assay was used to indicate cell death. ATP levels were measured using a luminometric assay.Key results: Adenosine markedly reduced cellular injury, with maximal cytoprotective effect at 100 µM and an EC50value of 14 µM. Inosine was also found to be cytoprotective. The selective A3adenosine receptor antagonist MRS 1523 attenuated the protective effects of adenosine and inosine, while an A3adenosine receptor agonist provided a partial protective effect. Adenosine deaminase inhibition attenuated the cytoprotective effect of adenosine but not of inosine during COGD. Inhibition of adenosine kinase reduced the protective effects of both adenosine and inosine during COGD. Pretreatment of the cells with adenosine or inosine markedly protected against the fall in cellular ATP content in the cells subjected to COGD.Conclusions and implications: The cytoprotection elicited by adenosine and inosine in a model of renal ischaemia involved both interactions with cell surface adenosine receptors on renal tubular epithelial cells and intracellular metabolism and conversion of adenosine to ATP.
Mothering Mexico: The Historiography of Mothers and Motherhood in 20th‐Century Mexico
Authors: Sanders Nichole 
Published: October 2009

AbstractThis essay explores how both scholars have understood the category of motherhood in 20th‐century Mexican history. From the self‐sacrificing, long‐suffering icon of ‘traditional’ motherhood to the ‘modern’ mother who used up‐to‐date child‐rearing techniques, mothers and mothering has had a tremendous symbolic value to various parts of Mexican society. The discourse of motherhood was deployed in multiple ways, by multiple actors since Porfirian times and throughout the postrevolutionary era. A robust scholarship has developed around the concept of mothers, motherhood and maternity.