bluuebunny/crossref_metadata_2025 huggingface dataset:
Gene length and expression level shape genomic novelties
Authors: Grishkevich Vladislav , Yanai Itai
Published: July 2014

Gene duplication and alternative splicing are important mechanisms in the production of genomic novelties. Previous work has shown that a gene’s family size and the number of splice variants it produces are inversely related, although the underlying reason is not well understood. Here, we report that gene length and expression level together explain this relationship. We found that gene lengths correlate with both gene duplication and alternative splicing: Longer genes are less likely to produce duplicates and more likely to exhibit alternative splicing. We show that gene length is a dynamic property, increasing with evolutionary time—due in part to the insertions of transposable elements—and decreasing following partial gene duplications. However, gene length alone does not account for the relationship between alternative splicing and gene duplication. A gene’s expression level appears both to impose a strong constraint on its length and to restrict gene duplications. Furthermore, high gene expression promotes alternative splicing, in particular for long genes, and alternatively, short genes with low expression levels have large gene families. Our analysis of the human and mouse genomes shows that gene length and expression level are primary genic properties that together account for the relationship between gene duplication and alternative splicing and bias the origin of novelties in the genome.
High resolution mapping of modified DNA nucleobases using excision repair enzymes
Authors: Bryan D. Suzi , Ransom Monica , Adane Biniam , York Kerri , Hesselberth Jay R.
Published: July 2014

The incorporation and creation of modified nucleobases in DNA have profound effects on genome function. We describe methods for mapping positions and local content of modified DNA nucleobases in genomic DNA. We combined in vitro nucleobase excision with massively parallel DNA sequencing (Excision-seq) to determine the locations of modified nucleobases in genomic DNA. We applied the Excision-seq method to map uracil in E. coli and budding yeast and discovered significant variation in uracil content, wherein uracil is excluded from the earliest and latest replicating regions of the genome, possibly driven by changes in nucleotide pool composition. We also used Excision-seq to identify sites of pyrimidine dimer formation induced by UV light exposure, where the method could distinguish between sites of cyclobutane and 6-4 photoproduct formation. These UV mapping data enabled analysis of local sequence bias around pyrimidine dimers and suggested a preference for an adenosine downstream from 6-4 photoproducts. The Excision-seq method is broadly applicable for high precision, genome-wide mapping of modified nucleobases with cognate repair enzymes.
RSC-dependent constructive and destructive interference between opposing arrays of phased nucleosomes in yeast
Authors: Ganguli Dwaipayan , Chereji Răzvan V. , Iben James R. , Cole Hope A. , Clark David J.
Published: July 2014

RSC and SWI/SNF are related ATP-dependent chromatin remodeling machines that move nucleosomes, regulating access to DNA. We addressed their roles in nucleosome phasing relative to transcription start sites in yeast. SWI/SNF has no effect on phasing at the global level. In contrast, RSC depletion results in global nucleosome repositioning: Both upstream and downstream nucleosomal arrays shift toward the nucleosome-depleted region (NDR), with no change in spacing, resulting in a narrower and partly filled NDR. The global picture of RSC-depleted chromatin represents the average of a range of chromatin structures, with most genes showing a shift of the +1 or the −1 nucleosome into the NDR. Using RSC ChIP data reported by others, we show that RSC occupancy is highest on the coding regions of heavily transcribed genes, though not at their NDRs. We propose that RSC has a role in restoring chromatin structure after transcription. Analysis of gene pairs in different orientations demonstrates that phasing patterns reflect competition between phasing signals emanating from neighboring NDRs. These signals may be in phase, resulting in constructive interference and a regular array, or out of phase, resulting in destructive interference and fuzzy positioning. We propose a modified barrier model, in which a stable complex located at the NDR acts as a bidirectional phasing barrier. In RSC-depleted cells, this barrier has a smaller footprint, resulting in narrower NDRs. Thus, RSC plays a critical role in organizing yeast chromatin.
Discovery of a bifunctional acyltransferase responsible for ornithine lipid synthesis in Serratia proteamaculans
Authors: Vences‐Guzmán Miguel Ángel , Guan Ziqiang , Escobedo‐Hinojosa Wendy Itzel , Bermúdez‐Barrientos José Roberto , Geiger Otto , Sohlenkamp Christian
Published: July 2014

Ornithine lipids (OLs) are phosphorus‐free membrane lipids that can be formed by many bacteria but that are absent from archaea and eukaryotes. A function for OLs in stress conditions and in host–bacteria interactions has been shown in some bacteria. Some bacterial species have been described that can form OLs, but lack the known genes (olsBA) involved in its biosynthesis, which implied the existence of a second pathway. Here we describe the bifunctional protein OlsF from Serratia proteamaculans involved in OL formation. Expression of OlsF and its homologue from Flavobacterium johnsoniae in Escherichia coli causes OL formation. Deletion of OlsF in S. proteamaculans caused the absence of OL formation. Homologues of OlsF are widely distributed among γ‐, δ‐ and ε‐Proteobacteria and in the Cytophaga‐Flavobacterium‐Bacteroidetes group of bacteria, including several well‐studied pathogens for which the presence of OLs has not been suspected, such as for example Vibrio cholerae and Klebsiella pneumonia. Using genomic data, we predict that about 50% of bacterial species can form OLs.
Strained fermented milks – A review of existing legislative provisions, survey of nutritional labelling of commercial products in selected markets and terminology of products in some selected countries
Authors: Tamime Adnan Y , Hickey Michael , Muir David D
Published: July 2014

A survey of the information contained in the labels of 109 commercial concentrated fermented milks from the Eastern Mediterranean, Australasia, the United Kingdom, Ireland, the United States of America and Canada plus Skyr (from Iceland), Ymer (from Denmark) and Chakka (from India) was carried out in late 2012 and early 2013. There were substantial differences in composition. The carbohydrate, fat and protein contents ranged between 1–12, 0–20 and 3.3–11 g/100 g, respectively. Considering the compositional data of the product and existing legislative provisions, a typical strained product should have a protein content of ≥8 g/100 and ~5 g/100 g of carbohydrates, and it would be appropriate to name such products as ‘strained yoghurt’, ‘Greek strained yoghurt’ and/or ‘Labneh’. A higher content of carbohydrate would suggest that the product was made using the product formulation method (i.e. without straining the fermentate), or the milk base had been fortified with skimmed milk before straining the fermentate to enhance the yield of the product, and such products should be known, for example, as ‘Greek‐style yoghurt’. It was also observed in some of the samples that the nomenclature of the starter cultures did not conform to recommendations of the International Union of Microbiological Societies (IUMS). Manufacturers could address such issues to minimise consumer confusion.
Standardized Descriptive Method for the Anthropological Evaluation of Pediatric Skull Fractures
Authors: Wiersema Jason M. , Love Jennifer C. , Derrick Sharon M. , Pinto Deborrah C. , Donaruma‐Kwoh Marcella , Greeley Christopher S.
Published: July 2014

The literature pertaining to pediatric skull fracture is primarily clinically based and thus motivated by the need for effective assessment of both fracture characteristics (type, frequency, location, and mechanics) and context (severity of injury, associated soft tissue damage, and prognosis). From a strictly descriptive standpoint, these schemas employ overlapping levels of detail that confound the nonclinical description of fractures in the forensic context. For this reason, application of these schemas in the forensic anthropological interpretation of skull fractures is inappropriate. We argue that forensic anthropological interpretation of skull fractures requires a standard classification system that reflects fracture morphology alone, and we suggest a three‐stepped classification system that conveys increasing detail with each additional step. A retrospective application of the method to a sample of 31 children aged 1 month to 2 years demonstrated its efficacy in the description of pediatric skull fractures.
Radiocarbon Analysis of Human Remains: A Review of Forensic Applications
Authors: Ubelaker Douglas H.
Published: July 2014

Radiocarbon analysis of organic materials, with the comparison of values with those of the post‐1950 modern bomb curve, has proven useful in forensic science to help evaluate the antiquity of evidence. Applications are particularly helpful in the study of human remains, especially with those displaying advanced decomposition of soft tissues. Radiocarbon analysis can reveal if the remains relate to the modern, post‐1950 era and if so, also provide information needed to evaluate the death and birth date. Sample selection and interpretation of results must be guided by knowledge of the formation and remodeling of different human tissues, as well as contextual information and the approximate age at death of the individual represented. Dental enamel does not remodel and thus captures dietary radiocarbon values at the time of juvenile formation. Most other human tissues do remodel but at differing rates and therefore collectively offer key information relative to the estimation of the death date.
Stable isotopes reveal ecological differences amongst now‐extinct proboscideans from the Cincinnati region, USA
Authors: Baumann Eric J. , Crowley Brooke E.
Published: July 2014

The mobility and dietary preferences of now‐extinct proboscideans have not been comprehensively examined in the central USA. We used stable carbon (δ13C), oxygen (δ18O) and strontium (87Sr/86Sr) isotopic signatures in molar enamel to investigate the foraging ecology of four mastodons (Mammut americanum) and eight mammoths (Mammuthus spp.) from southwestern Ohio and northwestern Kentucky. We tested two hypotheses: (i) these individuals were nomadic migrants that were passing through the region when they died; and (ii) mammoths and mastodons foraged in different environments. Unexpectedly, our results suggest that 11 of the 12 sampled individuals were regional residents. With the exception of one mastodon, 87Sr/86Sr ratios for proboscideans and regional water samples were statistically indistinguishable; slightly lower ratios for waters suggest glacial loess has an impact on modern samples. Amongst the individuals identified as residents, 87Sr/86Sr ratios indicate that mammoths and mastodons foraged in discrete geographical areas, and δ13C values imply dietary differences between the genera, which is consistent with our expectations. Oxygen isotope values may be able to distinguish animals that lived during the Last Glacial Maximum (LGM) from those that lived more recently. Three mammoths and one mastodon yielded δ18O values that are similar to modern regional precipitation and surface water, but too high for estimated drinking water during the LGM. We propose that these individuals lived during a relatively warm period following the LGM. Compellingly, the mammoth with the highest δ18O value also has the lowest δ13C value, suggesting that this individual was alive after regional vegetation shifted from open parkland to deciduous forest dominated by C3 species. Our results demonstrate that a wealth of information can be gleaned from fossil museum specimens and lay a foundation for future work on the foraging ecology of proboscideans and other extinct megafauna from the Midwest USA.
The Spacing Effect in Children's Generalization of Knowledge: Allowing Children Time to Forget Promotes Their Ability to Learn
Authors: Vlach Haley A.
Published: July 2014

Distributing learning events in time promotes memory to a greater degree than massing learning together in immediate succession, a phenomenon known as the spacing effect. In this article, I review research on the spacing effect in children's acquisition and generalization of conceptual knowledge. For decades, researchers hypothesized that spaced learning should deter generalization because the forgetting that occurs between learning events limits children's ability to retrieve prior learning. However, new research suggests that spaced learning promotes children's generalization and implicates forgetting as the mechanism that supports, rather than deters, children's generalization. This work counters the intuitive assumption that forgetting uniformly constrains children's learning, suggesting instead that forgetting is a domain‐general process that promotes cognitive development.
Over 1000 Aluminium Cans for Forty Dollars: The Provisioning Contributions of Older Children from the Perspectives of Welfare‐Reliant Lone Mothers
Authors: Liegghio Maria
Published: July 2014

In this article, as a child and family mental health therapist, I connect the feminist concept of ‘provisioning’ and the experiences of ‘young carers’ to critically examine the family care contributions made by older children living in poverty. I present the findings of a qualitative study consisting of two focus groups in which ten (n = 10) welfare‐reliant lone mothers living inToronto,Canada described the nature and significance of the contributions made by their older children (11–17 years old) to help their families ‘make ends meet’. Using grounded theory, two main categories emerged: (1) the nature of the provisioning by older children, and (2) the significance of the contributions. The implications of the findings suggest that mental health approaches with older children living in poverty inappropriately misrepresent and pathologise their emotional distress and family contributions.
Big Data and Large Sample Size: A Cautionary Note on the Potential for Bias
Authors: Kaplan Robert M. , Chambers David A. , Glasgow Russell E.
Published: July 2014

A number of commentaries have suggested that large studies are more reliable than smaller studies and there is a growing interest in the analysis of “big data” that integrates information from many thousands of persons and/or different data sources. We consider a variety of biases that are likely in the era of big data, including sampling error, measurement error, multiple comparisons errors, aggregation error, and errors associated with the systematic exclusion of information. Using examples from epidemiology, health services research, studies on determinants of health, and clinical trials, we conclude that it is necessary to exercise greater caution to be sure that big sample size does not lead to big inferential errors. Despite the advantages of big studies, large sample size can magnify the bias associated with error resulting from sampling or study design. Clin Trans Sci 2014; Volume #: 1–5
Leukemia inhibitor factor promotes functional recovery and oligodendrocyte survival in rat models of focal ischemia
Authors: Rowe Derrick D. , Collier Lisa A. , Seifert Hilary A. , Chapman Cortney B. , Leonardo Christopher C. , Willing Alison E. , Pennypacker Keith R.
Published: July 2014

Human umbilical cord blood (HUCB) cells have shown efficacy in rodent models of focal ischemia and in vitro systems that recapitulate stroke conditions. One potential mechanism of protection is through secretion of soluble factors that protect neurons and oligodendrocytes (OLs) from oxidative stress. To overcome practical issues with cellular therapies, identification of soluble factors released by HUCB and other stem cells may pave the way for treatment modalities that are safer for a larger percentage of stroke patients. Among these soluble factors is leukemia inhibitory factor (LIF), a cytokine that exerts pleiotropic effects on cell survival. Here, data show that LIF effectively reduced infarct volume, reduced white matter injury and improved functional outcomes when administered to rats following permanent middle cerebral artery occlusion. To further explore downstream signaling, primary oligodendrocyte cultures were exposed to oxygen–glucose deprivation to mimic stroke conditions. LIF significantly reduced lactate dehydrogenase release from OLs, reduced superoxide dismutase activity and induced peroxiredoxin 4 (Prdx4) transcript. Additionally, the protective and antioxidant capacity of LIF was negated by both Akt inhibition and co‐incubation with Prdx4‐neutralising antibodies, establishing a role for the Akt signaling pathway and Prdx4‐mediated antioxidation in LIF protection.
Pheromone Blend Does not Explain Old Male Mating Advantage in a Butterfly
Authors: Kehl Tobias , Burmeister Martin F. W. T. , Donke Elisabeth , Köhn Nora A. K. , Metschke Katja , Pfender David , Karl Isabell , Fischer Klaus
Published: July 2014

In several insect species, male mating success is higher in older than in younger males, although condition diminishes dramatically with age. Two hypotheses are under debate to explain the counterintuitive pattern of old male mating advantage: first, an increased eagerness of older males to mate, driven by their low residual reproductive value, and second female preference for older males based on chemical cues such as sex pheromones (female choice hypothesis). In a series of experiments, we manipulated female olfaction, male pheromone blend and female age to test whether old male mating advantage prevails when the influence of male sex pheromones is controlled for, using the tropical butterfly Bicyclus anynana as model. We found that older males had a higher mating success than younger ones irrespective of female scent‐sensitivity and irrespective of male pheromone blend. Interestingly, older males were found to court more often and for longer time bouts than younger males. These results were independent of female age, although younger males courted younger females more often and for longer bouts than older females. Taken together, our results indicate that male courtship activity (1) is higher in older compared to younger males and (2) increases the mating success of older males. Olfaction and sensing pheromones, in contrast, were not a necessary prerequisite for old male mating advantage to occur and may use other cues than pheromones to assess male quality.
Wheat germ agglutinin as a counterstain for immunofluorescence studies of equine hoof lamellae
Authors: Clark Robert K. , Galantino‐Homer Hannah L.
Published: July 2014

Equine laminitis is a common, painful, debilitating condition of the hoof that is a leading cause of disability in horses, often necessitating euthanasia. The equine hoof represents an extreme evolutionary adaptation of an epidermal structure homologous to the human or murine nail units. Immunohistochemistry is frequently utilized in the study of the pathophysiology of laminitis. The complex, multilayered, extensively interdigitated epidermal–dermal lamellar interface renders precise interpretation of immunofluorescence localization difficult, especially when effective technique and reagents render non‐reactive tissues completely dark. Fluorescent‐conjugated wheat germ agglutinin (WGA) selectively labels dermal extracellular matrix fibres and epidermal cell membranes in tissue sections of horse hoof lamellae, is compatible with indirect immunofluorescence and augments interpretation of indirect immunofluorescence antigen localization. The current report details the use of WGA as a rapid, simple, economical counterstain for immunofluorescence studies of the equine hoof and may have application to other complex epidermal tissue structures.
Qualified doctor and medical students' use of resources for accessing information: what is used and why?
Authors: Brennan Nicola , Edwards Sarah , Kelly Narcie , Miller Alice , Harrower Lucy , Mattick Karen
Published: July 2014

Background

Learning to access information using resources such as books and search engines is an important and fast changing challenge for doctors and medical students. Many resources exist to support evidence‐based clinical decision‐making, but a wide range of factors influences their use.

Objective

To explore qualified doctor and medical students' use of resources for accessing information and to determine what is used and why.

Methods

A stratified sample of 46 participants was recruited in Devon, UK. Participants kept a self‐report diary of resources used over a week. The diaries were then used to stimulate recall within a semi‐structured interview. Diary data were collated into tables of resource use. Qualitative data from the interviews were transcribed verbatim and thematically analysed.

Results

Many resources were used by participants but typically for a short duration of time. Categories of reasons for accessing resources were ‘to check’, ‘to learn’ and ‘to demonstrate’. The two main factors influencing choice of information resource were ‘ease of access’ and ‘quality of information’. Students accessed more information, for a longer duration.

Discussion & Conclusion

Resources must be quick to use, easy to access and tailored to the different purposes that they serve for qualified doctors and medical students.
The Timing of our Tooth Growth is an Evolutionary Relic
Authors: Dean Christopher , Cole Tim
Published: July 2014

Our teeth grow quickly, then slowly, then speed up again. But the rate of growth has not kept pace with our evolutionary history. Christopher Dean and Tim Cole find a fascinating link that sheds light on how humans diverged from apes.
Comparing Three Life Cycle Impact Assessment Methods from an Endpoint Perspective
Authors: Weidema Bo P
Published: July 2014

The impact assessment methods Eco‐Indicator 99 (H), Stepwise2006, and ReCiPe2008 (H) are compared with respect to the relative and absolute importance that they assign to the different mid‐point impact categories. The comparison is done by a common monetary valuation of the three endpoints that are common to the three methods: human well‐being, nature, and resources. Land use, global warming, and respiratory inorganic pollutants together make up between 86% and 97% of the overall impacts compared in all three methods. The overall monetarized impacts amount to 30%, 28%, and 165% of the gross domestic product (GDP), respectively. Resource depletion, land use, and global warming explain 99.5% of the positive deviation of ReCiPe2008, relative to the other two methods. The main causes for these differences are investigated and discussed, pointing to possibly questionable calculations and assumptions, for example, regarding the nonsubstitutability of resources and the very long relaxation time for transformed forestland in the relatively new ReCiPe2008 method, which leads us to recommend users to be cautious and critical when interpreting the results. Sensitivity analysis is made for other cultural perspectives and normalization references.
Prevention of Stroke in Sickle Cell Anemia
Authors: Adams Robert J.
Published: July 2014

Sickle cell anemia (SCD) is a disease characterized by abnormal hemoglobin (Hb) structure. There is a mutation in the beta-globin gene that changes the sixth amino acid from glutamic acid to valine causing the mutated hemoglobin (HbS) to polymerize reversibly when deoxygenated to form a gelatinous network of fibrous polymers that stiffen and distort the red blood cell (RBC) membrane. This leads to episodes of microvascular vasoocclusion and premature RBC destruction leading to hemolytic anemia. For reasons that are unclear, some children develop a large artery vasculopathy (gradual narrowing and ultimate occlusion causing deprivation of blood to the brain — a stroke in other words) involving the intracranial arteries supplying the brain.

The risk of stroke for a child with SCD is many times greater than that of a healthy child without SCD or heart disease. There is a technique that allows the identification of the children with SCD who have high risk even within this relatively high-risk group. And there is a highly effective preventive treatment.
URBANIZATION AND URBAN SYSTEMS IN THE PEOPLE'S REPUBLIC OF CHINA: RESEARCH FINDINGS AND POLICY RECOMMENDATIONS
Authors: Lu Ming , Wan Guanghua
Published: July 2014

This paper provides a literature review on urbanization in the People's Republic of China (PRC). Research findings indicate that the PRC's urbanization is incomplete: its level of urbanization lags behind its industrialization and development status, and while there are too many small cities, the large cities are not large enough. This is mainly because of the institutional constraints exerted by the Hukou and land systems on labor mobility, which have led to segregation, efficiency loss, distortion in the urban system and adverse impacts on equity, as discussed in this study. Major policy recommendations are offered for removing the distortions and steering the PRC's urbanization onto an efficient and equitable path.
Comparison of the effects on glycaemic control and β‐cell function in newly diagnosed type 2 diabetes patients of treatment with exenatide, insulin or pioglitazone: a multicentre randomized parallel‐group trial (the CONFIDENCE study)
Authors: Xu W. , Bi Y. , Sun Z. , Li J. , Guo L. , Yang T. , Wu G. , Shi L. , Feng Z. , Qiu L. , Li Q. , Guo X. , Luo Z. , Lu J. , Shan Z. , Yang W. , Ji Q. , Yan L. , Li H. , Yu X. , Li S. , Zhou Z. , Lv X. , Liang Z. , Lin S. , Zeng L. , Yan J. , Ji L. , Weng J.
Published: July 2014

Objective

Progressive β‐cell dysfunction hinders the maintenance of glycaemic control in type 2 diabetes, but comparative data on β‐cell‐protective therapies are lacking in the early stage of type 2 diabetes. Here we evaluated the comparative glycaemic efficacy and impact on β‐cell function of three antihyperglycaemic agents that have a β‐cell‐protective effect, exenatide, insulin and pioglitazone, in newly diagnosed patients with type 2 diabetes.

Design and methods

In this 48‐week, multicentre, parallel‐group study, 416 patients newly diagnosed with type 2 diabetes were randomly assigned 1 : 1 : 1 to receive exenatide, insulin or pioglitazone. The primary end‐point was the change in glycosylated haemoglobin (HbA1c) from baseline. Secondary end‐points included effects on weight, blood pressure, lipid profiles and β‐cell function assessed by homeostasis model assessment, fasting proinsulin:insulin (PI/I), disposition index (DI) and acute insulin response (AIR).

Results

At week 48, mean [95% confidence interval (CI)] HbA1c changes from baseline were −1.8% (−1.55% to −2.05%) with exenatide, −1.7% (−1.52% to −1.96%) with insulin and −1.5% (−1.23% to −1.71%) with pioglitazone. Treatment differences were −0.20% (95% CI −0.46% to 0.06%) for exenatide versus insulin (P = 0.185), and −0.37% (95% CI −0.63% to −0.12%) for exenatide versus pioglitazone (P = 0.002). Significant improvements from baseline in AIR, PI/I and DI were observed with all treatments, with the greatest improvements in DI, as well as weight, blood pressure and lipid profile, observed with exenatide.

Conclusions

All three agents showed efficacy regarding glycaemic control and metabolic benefits; however, exenatide showed the greatest efficacy. β‐cell function improved in all treatment groups; hence, early initiation of β‐cell‐protective therapy may halt the decline in β‐cell function in type 2 diabetes.
Prediction of Long‐Term Outcome by Measurement of Serum Concentration of Cardiac Troponins in Critically Ill Dogs with Systemic Inflammation
Authors: Langhorn R. , Thawley V. , Oyama M.A. , King L.G. , Machen M.C. , Trafny D.J. , Willesen J.L. , Tarnow I. , Kjelgaard‐Hansen M.
Published: July 2014

Background

Myocardial injury, detected by cardiac troponin I and T (cTnI and cTnT), has been associated with long‐term death in the noncardiac human intensive care unit (ICU).

Hypothesis

Presence of myocardial injury predicts 1‐year case fatality in critically ill dogs with systemic inflammation.

Animals

Thirty‐eight dogs with evidence of systemic inflammation and no primary cardiac disease.

Methods

Prospective cohort study. In dogs admitted to the ICU with evidence of systemic inflammation, blood samples were obtained at ICU admission for measurement of cTnI and cTnT, and cTnI was measured once daily during ICU hospitalization. Receiver operating characteristic (ROC) curves were used to examine prognostic capacity of admission cTnI, admission cTnT, and peak cTnI concentrations.

Results

One‐year case fatality rate was 47% (18/38 dogs). Admission cTnI concentrations were (median [range]) 0.48 [0.004–141.50] ng/mL, and peak cTnI concentrations were 1.21 [0.021–141.50] ng/mL. Admission cTnT concentrations were 15 [<13–3744] ng/L. For each marker, non‐survivors had significantly higher concentrations than survivors (P = .0082–.038). ROC analyses revealed areas under curves [95% CI] of 0.707 [0.537–0.843] for peak cTnI and 0.739 [0.571–0.867] for admission cTnT, respectively. At the optimal cut‐off, concentrations were 1.17 ng/mL (peak cTnI) and 23 ng/L (admission cTnT), sensitivities were 72% and 72%, and specificities were 70% and 80%, respectively.

Conclusions and Clinical Importance

While peak cTnI and admission cTnT are significantly related to 1‐year case fatality in critically ill dogs with systemic inflammation, low sensitivities and specificities prevent their prediction of long‐term outcome in individual patients. Troponins might play a role in identification of dogs at long‐term risk of death.
Flowering time QTL in natural populations of Arabidopsis thaliana and implications for their adaptive value
Authors: Dittmar Emily L. , Oakley Christopher G. , Ågren Jon , Schemske Douglas W.
Published: July 2014

The genetic basis of phenotypic traits is of great interest to evolutionary biologists, but their contribution to adaptation in nature is often unknown. To determine the genetic architecture of flowering time in ecologically relevant conditions, we used a recombinant inbred line population created from two locally adapted populations of Arabidopsis thaliana from Sweden and Italy. Using these RILs, we identified flowering time QTL in growth chambers that mimicked the natural temperature and photoperiod variation across the growing season in each native environment. We also compared the genomic locations of flowering time QTL to those of fitness (total fruit number) QTL from a previous three‐year field study. Ten total flowering time QTL were found, and in all cases, the Italy genotype caused early flowering regardless of the conditions. Two QTL were consistent across chamber environments, and these had the largest effects on flowering time. Five of the fitness QTL colocalized with flowering time QTL found in the Italy conditions, and in each case, the local genotype was favoured. In contrast, just two flowering time QTL found in the Sweden conditions colocalized with fitness QTL and in only one case was the local genotype favoured. This implies that flowering time may be more important for adaptation in Italy than Sweden. Two candidate genes (FLC and VIN3) underlying the major flowering time QTL found in the current study are implicated in local adaptation.
Is there an association between root architecture and mycorrhizal growth response?
Authors: Maherali Hafiz
Published: July 2014

The symbiosis between arbuscular mycorrhizal (AM) fungi and plants is evolutionarily widespread. The response of plant growth to inoculation by these fungi (mycorrhizal growth response; MGR) is highly variable, ranging from positive to negative. Some of this variation is hypothesized to be associated with root structure and function. Specifically, species with a coarse root architecture, and thus a limited intrinsic capacity to absorb soil nutrients, are expected to derive the greatest growth benefit from inoculation with AM fungi.

To test this hypothesis, previously published literature and phylogenetic information were combined in a meta‐analysis to examine the magnitude and direction of relationships among several root architectural traits and MGR.

Published studies differed in the magnitude and direction of relationships between root architecture and MGR. However, when combined, the overall relationship between MGR and allocation to roots, root diameter, root hair length and root hair density did not differ significantly from zero.

These findings indicate that possessing coarse roots is not necessarily a predictor of plant growth response to AM fungal colonization. Root architecture is therefore unlikely to limit the evolution of variation in MGR.
Refinement of Ischemic Stroke Risk in Patients with Atrial Fibrillation and CHA2DS2‐VASc Score of 1
Authors: HUANG DUO , ANGUO LUO , YUE WEN‐SHENG , YIN LIXUE , TSE HUNG‐FAT , SIU CHUNG‐WAH
Published: July 2014

Background

 Patients with atrial fibrillation (AF) with CHA2DS2‐VASc score of 1 (where CHA2DS2‐VASc is CHA2DS2‐Vascular disease, Age 65–74 years, Sex category) are recommended to receive antithrombotic therapy. Nonetheless, it remains unclear whether individual components that constitute CHA2DS2‐VASc score contribute equally to the ischemic stroke risk, particularly in patients with CHA2DS2‐VASc score of 1. The objective was to describe and compare the risk of ischemic stroke of the six individual components constituting CHA2DS2‐VASc among AF patients with CHA2DS2‐VASc score of 1.

Methods and Results

We studied all patients with CHA2DS2‐VASc score of 1 and no antithrombotic therapy from our cohort of 9,727 Chinese AF patients. A total of 548 patients were studied: 190 patients with CHA2DS2‐VASc score of 0 and 358 patients with CHA2DS2‐VASc score of 1. Of those with a baseline CHA2DS2‐VASc score of 1, 51.1% patients aged 65–75; 29.3% patients were female; 12.0% had hypertension; 4.5% had heart failure; 2.5% had diabetes; and 0.6% had vascular disease. After 1,758 patient‐years of follow‐up, the annual incidence of stroke was 2.4% and 6.6% for patients with CHA2DS2‐VASc score of 0 and 1, respectively. Compared with patients with CHA2DS2‐VASc score of 0, patients with hypertension leading to CHA2DS2‐VASc score of 1 were at the highest risk of stroke (Hazard ratio [HR]: 9.8, 95% confidence interval [CI]: 2.7–35.6), followed by patients aged 65–74 (HR: 3.9, 95% CI: 2.3–6.6) and female gender (HR: 2.3, 95% CI: 1.1–4.8). Heart failure, diabetes mellitus, and vascular disease were not associated with stroke.

Conclusion

In AF patients with CHA2DS2‐VASc score of 1, hypertension confers the highest risk for stroke among other risk factors comprising the score. A more aggressive thromboprophylaxis strategy may be justified among AF patients with CHA2DS2‐VASc score of 1 due to hypertension.
Evaluation of i‐gel™ airway in children: a meta‐analysis
Authors: Maitra Souvik , Baidya Dalim K. , Bhattacharjee Sulagna , Khanna Puneet
Published: July 2014

Background

I‐gel™ is a relatively newer addition in the pediatric anesthesia practice. Its comparison with the other laryngeal mask airway repor‐ted a wide range of results. Randomized controlled trials where i‐gel™ has been compared with other laryngeal masks (laryngeal mask airway ProSeal™ and laryngeal mask airway Classic™) in children for airway management device during general anesthesia has been included in this meta‐analysis.

Methods

PubMed and Central Register of Clinical Trials of the Cochrane Collaboration for eligible controlled trials using following search words: ‘i‐gel’, ‘i‐gel laryngeal mask airway’, ‘i‐gel children’, ‘i‐gel paediatric’ until February 15, 2014. A total nine prospective randomized controlled trials have been included in this meta‐analysis.

Results

Pooled analyses have found that i‐gel™ provided significantly higher oropharyngeal leak pressure than laryngeal mask airway ProSeal™ [496 participants, mean difference 2.07 cm H2O, 95% CI 0.52–3.62; P = 0.009] and a similar leak in comparison with laryngeal mask airway Classic™ [355 participants, mean difference 1.73 cm H2O, 95% CI −0.04, 3.51 cm H2O; P =0.06]. No difference was found in first insertion success rate and ease of insertion between i‐gel™, laryngeal mask airway ProSeal™, and laryngeal mask airway Classic™. Ease of gastric tube insertion is similar between i‐gel™ and laryngeal mask airway ProSeal™. Reported complications are infrequent and similar in all three devices.

Conclusion

We conclude that i‐gel™ is an effective alternative of the commonly used laryngeal mask airway ProSeal™ and laryngeal mask airway Classic™ in children for airway management during general anesthesia.
Anxiety sensitivity: Changes with puberty and cardiovascular variables
Authors: Akça Ömer Faruk , Ağaç Vural Tuba , Türkoğlu Serhat , Kılıç Emine Zinnur
Published: July 2014

Background

Anxiety sensitivity (AS) is a relatively stable dispositional variable that may increase the risk for anxiety‐related symptoms, particularly panic attack, among individuals of all age groups. Changes in AS during adolescence in healthy individuals, however, has not been previously investigated. The aim of this study was therefore to investigate the relationship of AS with puberty level, pulse rate, and blood pressure in healthy adolescents.

Methods

The sample consisted of 133 healthy adolescents (70 boys, 63 girls) aged 10–17 years. Puberty stage (i.e. Tanner stage), pulse rate, and blood pressure of each participant were determined. The Childhood Anxiety Sensitivity Inventory was used to identify AS. The correlations between AS and the clinical variables were assessed.

Results

AS was negatively correlated with pubertal stage when age and gender were controlled. Also, AS was correlated with diastolic blood pressure when age, gender, and pubertal stage were controlled (P < 0.05). Neither systolic blood pressure nor heart rate were correlated with AS.

Conclusion

AS, which is reported to be a trait‐like variable, may change during adolescence, due to the effect of pubertal growth and blood pressure interacting with AS during adolescence.
Physical activity cut‐offs and risk factors for preventing child obesity in Japan
Authors: Minematsu Kazuo , Kawabuchi Ryosuke , Okazaki Hiromi , Tomita Hiroyuki , Tobina Takuro , Tanigawa Takeshi , Tsunawake Noriaki
Published: July 2014

Background

There is no official recommendations for physical activity level or steps for preventing and improving child obesity in Japan.

Methods

Three hundred and two Japanese children aged 9–12 years were recruited wore 3‐D speed sensors. Subjects were divided into two groups using the criteria for child obesity in Japan. Body composition was measured on bioelectrical impedance analysis. Physical fitness test was done to evaluate physical strength. Twenty‐four hour total steps, energy expenditure, and metabolic equivalents (MET) from Monday to Sunday were consecutively measured. The cut‐offs for steps and physical activity level for preventing child obesity were evaluated on receiver operating characteristic curves. Daily life‐related risk factors for child obesity were assessed on logistic regression analysis.

Results

In both sexes, body volume; bodyweight, body mass index, fat mass, and percentage body fat in the obese group was significantly higher than in the normal group, but age and height were not different (P < 0.001). Aerobic power, running speed, and explosive strength in the obese group were inferior to those in the normal group (P < 0.001). More than 40 min of 4 MET exercise, defined as moderate–vigorous exercise, and 11 000 steps per day are essential to prevent child obesity. Additionally, >2 h TV viewing per day is a significant risk factor for child obesity (OR, 3.43; 95%CI: 1.27–9.31).

Conclusion

Cut‐offs for physical activity and potential risk factors for child obesity have been identified. Recommendations for changes to daily lifestyle for school‐aged Japanese children are given.
Changing face and clinical features of celiac disease in children
Authors: Gokce Selim , Arslantas Esra
Published: July 2014

Background

The aim of this study was to analyze and compare the epidemiological and presenting features, clinical patterns, and complications of celiac disease (CD) in children.

Methods

The clinical charts of children with CD were retrospectively analyzed. Data for children who presented during the first time period (January 2005–October 2008; group 1) were compared to those of children who presented during the second time period (November 2008–April 2012; group 2).

Results

Group 1 and 2 consisted of 96 and 95 children, respectively. There were no differences in gender distribution, weight, or height z‐scores between the two groups. Mean age at the time of diagnosis in group 2 (9.3 ± 4.5 years) was significantly higher than in group 1 (6.9 ± 3.9 years; P < 0.001). Non‐classical presentation was more frequent in group 2 (P = 0.01). Associated disorders were observed in 49 children (25.7%) overall. There were significantly more children with type 1 diabetes mellitus in group 2 (P = 0.030). In all, 11 patients (5.8%) were overweight (either obese or at risk of obesity) at presentation. Isolated short stature was the presenting feature in 15 children (7.9%) overall, but was more frequently observed in group 2 (P = 0.003). In total, 15 patients (7.9%) presented with refractory iron deficiency anemia; the frequency was similar in both groups. Dual‐energy X‐ray absorptiometry was performed in 102 patients, and 82 (80.4%) had metabolic bone disease (MBD).

Conclusion

The mode of presentation and clinical features of CD in childhood continue to change. Of note, a substantial percentage of patients were overweight at presentation. MBD is a frequent complication, necessitating routine evaluation.
Floodplain conservation in the Mississippi River Valley: combining spatial analysis, landowner outreach, and market assessment to enhance land protection for the Atchafalaya River Basin, Louisiana, U.S.A.
Authors: Piazza Bryan P. , Allen Yvonne C. , Martin Richard , Bergan James F. , King Katherine , Jacob Rick
Published: July 2014

Threats to riverine landscapes are often the result of system‐wide river management policy, located far from where the threats appear, or both. As a result, the rationale for land protection to achieve floodplain conservation and restoration has shifted to require that lands must also have multiple and systemic threat abatement benefits. The Mississippi River Flood of 2011 highlighted the need for increased floodplain complexes along the Mississippi River to provide both systemic threat abatement and conservation benefits. We used spatial analysis, landowner outreach, and market assessment to examine ways to enhance land protection in the Atchafalaya River Basin Floodway, the largest river basin swamp North America and the site of two employed floodway locations during the 2011 flood. We identified six Priority Conservation Areas (77,084 ha) in the floodway that are largely privately owned (mean 78.2 ± 6.4%), with forest dominated by Taxodium distichum (baldcypress) and hydrologic and water quality characteristics considered most suitable for baldcypress regeneration (31.2 ± 2.4% and 10.2 ± 3.0% of area, respectively). Landowners expressed high (80%) interest in land protection programs and found the range of property values derived from market analyzes (minimal protection—$346 USD/ha; additional protections—up to $2,223 USD/ha) to be reasonable. We seek to: (1) enhance current land protection in the Atchafalaya River Basin and (2) provide a model for using land protection to increase the number of floodplains for both systemic threat abatement and conservation benefits.
Systems approach identifies TGA1 and TGA4 transcription factors as important regulatory components of the nitrate response of Arabidopsis thaliana roots
Authors: Alvarez José M. , Riveras Eleodoro , Vidal Elena A. , Gras Diana E. , Contreras‐López Orlando , Tamayo Karem P. , Aceituno Felipe , Gómez Isabel , Ruffel Sandrine , Lejay Laurence , Jordana Xavier , Gutiérrez Rodrigo A.
Published: July 2014

Nitrate acts as a potent signal to control global gene expression in Arabidopsis. Using an integrative bioinformatics approach we identified TGA1 and TGA4 as putative regulatory factors that mediate nitrate responses in Arabidopsis roots. We showed that both TGA1 and TGA4 mRNAs accumulate strongly after nitrate treatments in roots. Global gene expression analysis revealed 97% of the genes with altered expression in tga1 tga4 double mutant plants respond to nitrate treatments, indicating that these transcription factors have a specific role in nitrate responses in Arabidopsis root organs. We found TGA1 and TGA4 regulate the expression of nitrate transporter genes NRT2.1 and NRT2.2. Specific binding of TGA1 to its cognate DNA sequence on NRT2.1 and NRT2.2 promoters was confirmed by chromatin immunoprecipitation assays. The tga1 tga4 double mutant plants exhibit nitrate‐dependent lateral and primary root phenotypes. Lateral root initiation is affected in both tga1 tga4 and nrt1.2 nrt2.2 double mutants, suggesting TGA1 and TGA4 regulate lateral root development at least partly via NRT2.1 and NRT2.2. Additional root phenotypes of tga1 tga4 double mutants indicate that these transcription factors play an important role in root developmental responses to nitrate. These results identify TGA1 and TGA4 as important regulatory factors of the nitrate response in Arabidopsis roots.
Discharge characteristics of motor units during long‐duration contractions
Authors: Pascoe Michael A. , Holmes Matthew R. , Stuart Douglas G. , Enoka Roger M.
Published: July 2014

New Findings

What is the central question of this study?

How long can humans sustain motor unit discharge during a voluntary contraction?

What is the main finding and its importance?

Human motor units can discharge action potentials for a longer time during a voluntary contraction than can be achieved by intracellular or extracellular current injection of motor neurons with in vivo and in vitro animal preparations. These recordings comprise a previously unexplored range of durations for human motor unit recordings during a continuously sustained isometric recording.

The purpose of the study was to determine how long humans could sustain the discharge of single motor units during a voluntary contraction. The discharge of motor units in first dorsal interosseus of subjects (27.8 ± 8.1 years old) was recorded for as long as possible. The task was terminated when the isolated motor unit stopped discharging action potentials, despite the ability of the individual to sustain the abduction force. Twenty‐three single motor units were recorded. Task duration was 21.4 ± 17.8 min. When analysed across discharge duration, mean discharge rate (10.6 ± 1.8 pulses s−1) and mean abduction force (5.5 ± 2.8% maximum) did not change significantly (discharge rate, P = 0.119; and abduction force, P = 0.235). In contrast, the coefficient of variation for interspike interval during the initial 30 s of the task was 22.2 ± 6.0% and increased to 31.9 ± 7.0% during the final 30 s (P < 0.001). All motor units were recruited again after 60 s of rest. Although subjects were able to sustain a relatively constant discharge rate, the cessation of discharge was preceded by a gradual increase in discharge variability. The findings also showed that the maximal duration of human motor unit discharge exceeds that previously reported for the discharge elicited in motor neurons by intracellular current injection in vitro.