bluuebunny/crossref_metadata_2025_split huggingface dataset:
Sports Specialization in Young Athletes
Authors: Jayanthi Neeru , Pinkham Courtney , Dugas Lara , Patrick Brittany , LaBella Cynthia 
Published: October 2012

Context: Sports specialization is intense training in 1 sport while excluding others. Sports specialization in early to middle childhood has become increasingly common. While most experts agree that some degree of sports specialization is necessary to achieve elite levels, there is some debate as to whether such intense practice time must begin during early childhood and to the exclusion of other sports to maximize potential for success. There is a concern that sports specialization before adolescence may be deleterious to a young athlete. Evidence Acquisition: PubMed and OVID were searched for English-language articles from 1990 to 2011 discussing sports specialization, expert athletes, or elite versus novice athletes, including original research articles, consensus opinions, and position statements. Results: For most sports, there is no evidence that intense training and specialization before puberty are necessary to achieve elite status. Risks of early sports specialization include higher rates of injury, increased psychological stress, and quitting sports at a young age. Sports specialization occurs along a continuum. Survey tools are being developed to identify where athletes fall along the spectrum of specialization. Conclusion: Some degree of sports specialization is necessary to develop elite-level skill development. However, for most sports, such intense training in a single sport to the exclusion of others should be delayed until late adolescence to optimize success while minimizing injury, psychological stress, and burnout.
Detection of obstructive sleep apnoea by an electronic nose
Authors: Greulich Timm , Hattesohl Akira , Grabisch Antje , Koepke Janine , Schmid Severin , Noeske Sarah , Nell Christoph , Wencker Marion , Jörres Rudolf A. , Vogelmeier Claus Franz , Köhler Ulrich , Koczulla Andreas Rembert 
Published: October 2012

Diagnosis of obstructive sleep apnoea syndrome (OSAS) is technically demanding, cost-intensive and time-consuming. The measurement of volatile organic compounds by an electronic nose is an innovative method that determines distinct molecular patterns of exhaled breath in different patient groups. We addressed the following questions: What is the diagnostic accuracy of an electronic nose in the detection of OSAS and the ability to detect effects of standard therapy in patients with OSAS? Are these results related to changes in distinct markers of airway inflammation and extracellular remodelling?We included 40 OSAS patients and 20 healthy controls. Exhaled breath of all participants was analysed using the Cyranose 320 electronic nose. Pharyngeal washings were performed to sample the upper airway compartment. For statistical analysis linear discriminant analysis was employed.We identified a linear discriminant function separating OSAS from control (p<0.0001). The corresponding area under the receiver-operating curve was 0.85 (95% CI 0.75–0.96; sensitivity 0.93 and specificity 0.7). In pharyngeal washing fluids of OSAS patients, we observed higher levels of α1-antitrypsin and markers of extracellular remodelling compared to controls.The electronic nose can distinguish between OSAS patients and controls with high accuracy.
Noninvasive cardiac output measurements in patients with pulmonary hypertension
Authors: Rich Jonathan D. , Archer Stephen L. , Rich Stuart 
Published: October 2012

Pulmonary hypertension (PH) is characterised by a progressive decline in cardiac output (CO) and right heart failure. NICOM® (noninvasive cardiac output monitor) is a bioreactance-based technology that has been broadly validated, but its specific application in right heart failure and PH is unknown.Cardiac catheterisation was performed in 50 consecutive patients with PH. CO measurements were performed using three different methods (thermodilution, Fick and NICOM) at baseline and after vasodilator challenge. We compared the precision (coefficient of variation) and accuracy of NICOM compared to thermodilution and Fick.The mean CO (L·min−1) at baseline as measured by the three methods was 4.73±1.15 (NICOM), 5.69±1.74 (thermodilution) and 4.84±1.39 (Fick). CO measured by NICOM was more precise than by thermodilution (3.5±0.3%versus9.6±6.1%, p<0.001). Bland–Altman analyses comparing NICOM to thermodilution and Fick revealed bias and 95% limits of agreement that were comparable to those comparing Fick to thermodilution. All three CO methods detected an increase in CO in response to vasodilator challenge.CO measuredviaNICOM is precise and reliably measures CO at rest and changes in CO with vasodilator challenge in patients with PH. NICOM may allow for the noninvasive haemodynamic assessment of patients with PH and their response to therapy.
Repeatability and responsiveness of exercise tests in pulmonary arterial hypertension
Authors: Mainguy Vincent , Malenfant Simon , Neyron Anne-Sophie , Bonnet Sébastien , Maltais François , Saey Didier , Provencher Steeve 
Published: October 2012

Exercise tolerance in pulmonary arterial hypertension (PAH) is most commonly assessed by the 6-min walk test (6MWT). Whether endurance exercise tests are more responsive than the 6MWT remains unknown.20 stable PAH patients (mean±sdage 53±15 years and mean pulmonary arterial pressure 44±16 mmHg) already on PAH monotherapy completed the 6MWT, the endurance shuttle walk test (ESWT) and the cycle endurance test (CET) before and after the addition of sildenafil citrate 20 mg three times daily or placebo for 28 days in a randomised double-blind crossover setting. Pre- or post-placebo tests were used to assess repeatability of each exercise test, whereas pre- or post-sildenafil citrate tests were used to assess their responsiveness.Sildenafil citrate led to placebo-corrected changes in exercise capacity of 18±25 m (p = 0.02), 58±235 s (p = 0.58) and 29±77 s (p = 0.09) for the 6MWT, the ESWT and the CET, respectively. The 6MWT was associated with a lower coefficient of variation between repeated measures (3%versus18%versus13%), resulting in a higher standardised response mean compared with endurance tests (0.72, 0.25 and 0.38 for the 6MWT, the ESWT and the CET, respectively).The 6MWT had the best ability to capture changes in exercise capacity when sildenafil citrate was combined with patients’ baseline monotherapy, supporting its use as an outcome measure in PAH.
Sleep disordered breathing in patients receiving therapy with buprenorphine/naloxone
Authors: Farney Robert J. , McDonald Amanda M. , Boyle Kathleen M. , Snow Gregory L. , Nuttall R.T. , Coudreaut Michael F. , Wander Theodore J. , Walker James M. 
Published: October 2012

Patients using chronic opioids are at risk for exceptionally complex and potentially lethal disorders of breathing during sleep, including central and obstructive apnoeas, hypopnoeas, ataxic breathing and nonapnoeic hypoxaemia. Buprenorphine, a partial μ-opioid agonist with limited respiratory toxicity, is widely used for the treatment of opioid dependency and chronic nonmalignant pain. However, its potential for causing sleep disordered breathing has not been studied.70 consecutive patients admitted for therapy with buprenorphine/naloxone were routinely evaluated with sleep medicine consultation and attended polysomnography.The majority of patients were young (mean±sdage 31.8±12.3 years), nonobese (mean±sdbody mass index 24.9±5.9 kg·m−2) and female (60%). Based upon the apnoea/hypopnoea index (AHI), at least mild sleep disordered breathing (AHI ≥5 events·h−1) was present in 63% of the group. Moderate (AHI ≥15– <30 events·h−1) and severe (AHI ≥30 events·h−1) sleep apnoea was present in 16% and 17%, respectively. Hypoxaemia, defined as an arterial oxygen saturation measured by pulse oximetry, of <90% for ≥10% of sleep time, was present in 27 (38.6%) patients.Despite the putative protective ceiling effect regarding ventilatory suppression observed during wakefulness, buprenorphine may induce significant alterations of breathing during sleep at routine therapeutic doses.
Haemodynamics, exercise capacity and clinical events in pulmonary arterial hypertension
Authors: Savarese Gianluigi , Musella Francesca , D'Amore Carmen , Losco Teresa , Marciano Caterina , Gargiulo Paola , Rengo Giuseppe , Dellegrottaglie Santo , Bossone Eduardo , Leosco Dario , Perrone-Filardi Pasquale 
Published: October 2012

The purpose of this study was to clarify whether changes in cardiopulmonary haemodynamics induced by pharmacological therapy correlate with exercise capacity and clinical events in patients with pulmonary arterial hypertension.16 randomised trials including 2353 patients, followed up for 16.4±10.6 weeks, measuring cardiopulmonary haemodynamics by right heart catheterisation and reporting clinical events were included. Meta-analysis and meta-regression analysis were performed to assess the effects of treatments on clinical events and the relationship between haemodynamic changes (pulmonary artery pressure, pulmonary vascular resistance, cardiac index and right atrial pressure) and clinical events.Treatments significantly reduced all-cause death (OR 0.5, 95% CI 0.3–0.7; p<0.01), hospitalisation for pulmonary arterial hypertension (OR 0.4, 95% CI 0.2–0.7; p<0.01), initiation of rescue therapy (OR 0.3, 95% CI 0.2–0.6; p<0.01) and the composite outcome (OR 0.3, 95% CI 0.3–0.5; p<0.01). No relationship was found between changes of haemodynamic parameters and clinical events, whereas changes of cardiac index and pulmonary vascular resistance significantly correlated with changes in the 6-min walking distance (r = 0.64, p = 0.03; r = -0.55, p = 0.04, respectively).In patients with pulmonary arterial hypertension, improvements of cardiopulmonary haemodynamics observed in randomised clinical trials correlate with exercise capacity changes but do not predict clinical events in a short-term follow-up.
A quantitative genetic and epigenetic model of complex traits
Authors: Wang Zhong , Wang Zuoheng , Wang Jianxin , Sui Yihan , Zhang Jian , Liao Duanping , Wu Rongling 
Published: October 2012

AbstractBackgroundDespite our increasing recognition of the mechanisms that specify and propagate epigenetic states of gene expression, the pattern of how epigenetic modifications contribute to the overall genetic variation of a phenotypic trait remains largely elusive.ResultsWe construct a quantitative model to explore the effect of epigenetic modifications that occur at specific rates on the genome. This model, derived from, but beyond, the traditional quantitative genetic theory that is founded on Mendel’s laws, allows questions concerning the prevalence and importance of epigenetic variation to be incorporated and addressed.ConclusionsIt provides a new avenue for bringing chromatin inheritance into the realm of complex traits, facilitating our understanding of the means by which phenotypic variation is generated.
Genome organization and characteristics of soybean microRNAs
Authors: Turner Marie , Yu Oliver , Subramanian Senthil 
Published: October 2012

Abstract

Background
microRNAs (miRNAs) are key regulators of gene expression and play important roles in many aspects of plant biology. The role(s) of miRNAs in nitrogen-fixing root nodules of leguminous plants such as soybean is not well understood. We examined a library of small RNAs from Bradyrhizobium japonicum-inoculated soybean roots and identified novel miRNAs. In order to enhance our understanding of miRNA evolution, diversification and function, we classified all known soybean miRNAs based on their phylogenetic conservation (conserved, legume- and soybean-specific miRNAs) and examined their genome organization, family characteristics and target diversity. We predicted targets of these miRNAs and experimentally validated several of them. We also examined organ-specific expression of selected miRNAs and their targets.

Results
We identified 120 previously unknown miRNA genes from soybean including 5 novel miRNA families. In the soybean genome, genes encoding miRNAs are primarily intergenic and a small percentage were intragenic or less than 1000 bp from a protein-coding gene, suggesting potential co-regulation between the miRNA and its parent gene. Difference in number and orientation of tandemly duplicated miRNA genes between orthologous genomic loci indicated continuous evolution and diversification. Conserved miRNA families are often larger in size and produce less diverse mature miRNAs than legume- and soybean-specific families. In addition, the majority of conserved and legume-specific miRNA families produce 21 nt long mature miRNAs with distinct nucleotide distribution and regulate a more conserved set of target mRNAs compared to soybean-specific families. A set of nodule-specific target mRNAs and their cognate regulatory miRNAs had inverse expression between root and nodule tissues suggesting that spatial restriction of target gene transcripts by miRNAs might govern nodule-specific gene expression in soybean.

Conclusions
Genome organization of soybean miRNAs suggests that they are actively evolving. Distinct family characteristics of soybean miRNAs suggest continuous diversification of function. Inverse organ-specific expression between selected miRNAs and their targets in the roots and nodules, suggested a potential role for these miRNAs in regulating nodule development.
Reducing confounding and suppression effects in TCGA data: an integrated analysis of chemotherapy response in ovarian cancer
Authors: Hsu Fang-Han , Serpedin Erchin , Hsiao Tzu-Hung , Bishop Alexander JR , Dougherty Edward R , Chen Yidong 
Published: October 2012

Abstract

Background
Despite initial response in adjuvant chemotherapy, ovarian cancer patients treated with the combination of paclitaxel and carboplatin frequently suffer from recurrence after few cycles of treatment, and the underlying mechanisms causing the chemoresistance remain unclear. Recently, The Cancer Genome Atlas (TCGA) research network concluded an ovarian cancer study and released the dataset to the public. The TCGA dataset possesses large sample size, comprehensive molecular profiles, and clinical outcome information; however, because of the unknown molecular subtypes in ovarian cancer and the great diversity of adjuvant treatments TCGA patients went through, studying chemotherapeutic response using the TCGA data is difficult. Additionally, factors such as sample batches, patient ages, and tumor stages further confound or suppress the identification of relevant genes, and thus the biological functions and disease mechanisms.

Results
To address these issues, herein we propose an analysis procedure designed to reduce suppression effect by focusing on a specific chemotherapeutic treatment, and to remove confounding effects such as batch effect, patient's age, and tumor stages. The proposed procedure starts with a batch effect adjustment, followed by a rigorous sample selection process. Then, the gene expression, copy number, and methylation profiles from the TCGA ovarian cancer dataset are analyzed using a semi-supervised clustering method combined with a novel scoring function. As a result, two molecular classifications, one with poor copy number profiles and one with poor methylation profiles, enriched with unfavorable scores are identified. Compared with the samples enriched with favorable scores, these two classifications exhibit poor progression-free survival (PFS) and might be associated with poor chemotherapy response specifically to the combination of paclitaxel and carboplatin. Significant genes and biological processes are detected subsequently using classical statistical approaches and enrichment analysis.

Conclusions
The proposed procedure for the reduction of confounding and suppression effects and the semi-supervised clustering method are essential steps to identify genes associated with the chemotherapeutic response.
C2Maps: a network pharmacology database with comprehensive disease-gene-drug connectivity relationships
Authors: Huang Hui , Wu Xiaogang , Pandey Ragini , Li Jiao , Zhao Guoling , Ibrahim Sara , Chen Jake Y 
Published: October 2012

Abstract

Background
Network pharmacology has emerged as a new topic of study in recent years. It aims to study the myriad relationships among proteins, drugs, and disease phenotypes. The concept of molecular connectivity maps has been proposed to establish comprehensive knowledge links between molecules of interest in a given biological context. Molecular connectivity maps between drugs and genes/proteins in specific disease contexts can be particularly valuable, since the functional approach with these maps helps researchers gain global perspectives on both the therapeutic profiles and toxicological profiles of candidate drugs.

Methods
To assess drug pharmacological effect, we assume that "ideal" drugs for a patient can treat or prevent the disease by modulating gene expression profiles of this patient to the similar level with those in healthy people. Starting from this hypothesis, we build comprehensive disease-gene-drug connectivity relationships with drug-protein directionality (inhibit/activate) information based on a computational connectivity maps (C2Maps) platform. An interactive interface for directionality annotation of drug-protein pairs with literature evidences from PubMed has been added to the new version of C2Maps. We also upload the curated directionality information of drug-protein pairs specific for three complex diseases - breast cancer, colorectal cancer and Alzheimer disease.

Results
For relevant drug-protein pairs with directionality information, we use breast cancer as a case study to demonstrate the functionality of disease-specific searching. Based on the results obtained from searching, we perform pharmacological effect evaluation for two important breast cancer drugs on treating patients diagnosed with different breast cancer subtypes. The evaluation is performed on a well-studied breast cancer gene expression microarray dataset to portray how useful the updated C2Maps is in assessing drug efficacy and toxicity information.

Conclusions
The C2Maps platform is an online bioinformatics resource that provides biologists with directional relationships between drugs and genes/proteins in specific disease contexts based on network mining, literature mining, and drug effect annotating. A new insight to assess overall drug efficacy and toxicity can be provided by using the C2Maps platform to identify disease relevant proteins and drugs. The case study on breast cancer correlates very well with the existing pharmacology of the two breast cancer drugs and highlights the significance of C2Maps database.
Application of binding pancreatogastrostomy in laparoscopic central pancreatectomy
Authors: Defei Hong , Ying Xin , Xiujun Cai , Shuyou Peng 
Published: October 2012

Abstract

Background
The feasibility of binding pancreaticogastrostomy in laparoscopic central pancreatectomy is not known.

Methods
In October 2011, a female patient with a pancreatic neck mass received laparoscopic central pancreatectomy with binding pancreaticogastrostomy.

Results
The operation was successful. No complications occurred. The operative time was 210 min. Blood loss was 120 ml. On day 11 after the operation, the patient was discharged. The postoperative pathological result showed a 2 × 2 × 2-cm solid pseudopapillary tumor of the pancreas with intrapancreatic infiltration. The surgical margin was negative.

Conclusions
Laparoscopic central pancreatectomy with binding pancreaticogastrostomy might be feasible, facilitating further study in laparoscopic pancreatoduodenectomy.

Trial registration
This study was waived from trial registration because it is a retrospective analysis of medical records.
Prolonged sedentary time and physical activity in workplace and non-work contexts: a cross-sectional study of office, customer service and call centre employees
Authors: Thorp Alicia A , Healy Genevieve N , Winkler Elisabeth , Clark Bronwyn K , Gardiner Paul A , Owen Neville , Dunstan David W 
Published: October 2012

Abstract

Background
To examine sedentary time, prolonged sedentary bouts and physical activity in Australian employees from different workplace settings, within work and non-work contexts.

Methods
A convenience sample of 193 employees working in offices (131), call centres (36) and customer service (26) was recruited. Actigraph GT1M accelerometers were used to derive percentages of time spent sedentary (<100 counts per minute; cpm), in prolonged sedentary bouts (≥20 minutes or ≥30 minutes), light-intensity activity (100–1951 cpm) and moderate-to-vigorous physical activity (MVPA; ≥1952 cpm). Using mixed models adjusted for confounders, these were compared for: work days versus non-work days; work hours versus non-work hours (work days only); and, across workplace settings.

Results
Working hours were mostly spent sedentary (77.0%, 95%CI: 76.3, 77.6), with approximately half of this time accumulated in prolonged bouts of 20 minutes or more. There were significant (p<0.05) differences in all outcomes between workdays and non-work days, and, on workdays, between work- versus non-work hours. Results consistently showed “work” was more sedentary and had less light-intensity activity, than “non-work”. The period immediately after work appeared important for MVPA. There were significant (p<0.05) differences in all sedentary and activity outcomes occurring during work hours across the workplace settings. Call-centre workers were generally the most sedentary and least physically active at work; customer service workers were typically the least sedentary and the most active at work.

Conclusion
The workplace is a key setting for prolonged sedentary time, especially for some occupational groups, and the potential health risk burden attached requires investigation. Future workplace regulations and health promotion initiatives for sedentary occupations to reduce prolonged sitting time should be considered.
Fast responsive, optical trace level ammonia sensor for environmental monitoring
Authors: Abel Tobias , Ungerböck Birgit , Klimant Ingo , Mayr Torsten 
Published: October 2012

Abstract

Background
Ammonia is a ubiquitous chemical substance which is created in technical and biological processes and harmful to many different organisms. One specific problem is the toxicity of ammonia in fish at levels of 25 μg/l - a very common issue in today’s aqua culture. In this study we report a development of a fast responsive, optical ammonia sensor for trace concentrations.

Results
Different hydrogels have been investigated as host polymers for a pH based sensing mechanism based on fluorescent dyes. A porous hydrophobic fluoropolymer membrane was used as an ion barrier cover layer to achieve a good ammonia permeability. The sensor’s sensitivity towards ammonia as well as crosssensitivity towards pH-value and salinity, and the temperature dependency have been determined. Two different methods to reference fluorescence signals have been employed to eliminate intensity-based measurement drawbacks.

Conclusion
The presented sensor features high sensitivity and a fast response even at concentrations near 1 ppb. No cross sensitivity towards pH and salinity could be observed and temperature dependency was determined as compensateable. Both referencing approaches prove themselves to be able to provide a simple use of the sensor for in-field applications.