bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Neuropathology of Chronic Traumatic Encephalopathy
Authors: McKee Ann C. , Stein Thor D. , Kiernan Patrick T. , Alvarez Victor E. 
Published: April 2015

AbstractRepetitive brain trauma is associated with a progressive neurological deterioration, now termed as chronic traumatic encephalopathy (CTE). Most instances of CTE occur in association with the play of sports, but CTE has also been reported in association with blast injuries and other neurotrauma. Symptoms of CTE include behavioral and mood changes, memory loss, cognitive impairment and dementia. Like many other neurodegenerative diseases, CTE is diagnosed with certainty only by neuropathological examination of brain tissue. CTE is a tauopathy characterized by the deposition of hyperphosphorylated tau (p‐tau) protein as neurofibrillary tangles, astrocytic tangles and neurites in striking clusters around small blood vessels of the cortex, typically at the sulcal depths. Severely affected cases show p‐tau pathology throughout the brain. Abnormalities in phosphorylated 43 kDa TAR DNA‐binding protein are found in most cases of CTE; beta‐amyloid is identified in 43%, associated with age. Given the importance of sports participation and physical exercise to physical and psychological health as well as disease resilience, it is critical to identify the genetic risk factors for CTE as well as to understand how other variables, such as stress, age at exposure, gender, substance abuse and other exposures, contribute to the development of CTE.
A Review of Neuroimaging Findings in Repetitive Brain Trauma
Authors: Koerte Inga K. , Lin Alexander P. , Willems Anna , Muehlmann Marc , Hufschmidt Jakob , Coleman Michael J. , Green Isobel , Liao Huijun , Tate David F. , Wilde Elisabeth A. , Pasternak Ofer , Bouix Sylvain , Rathi Yogesh , Bigler Erin D. , Stern Robert A. , Shenton Martha E. 
Published: April 2015

AbstractChronic traumatic encephalopathy (CTE) is a neurodegenerative disease confirmed at postmortem. Those at highest risk are professional athletes who participate in contact sports and military personnel who are exposed to repetitive blast events. All neuropathologically confirmed CTE cases, to date, have had a history of repetitive head impacts. This suggests that repetitive head impacts may be necessary for the initiation of the pathogenetic cascade that, in some cases, leads to CTE. Importantly, while all CTE appears to result from repetitive brain trauma, not all repetitive brain trauma results in CTE. Magnetic resonance imaging has great potential for understanding better the underlying mechanisms of repetitive brain trauma. In this review, we provide an overview of advanced imaging techniques currently used to investigate brain anomalies. We also provide an overview of neuroimaging findings in those exposed to repetitive head impacts in the acute/subacute and chronic phase of injury and in more neurodegenerative phases of injury, as well as in military personnel exposed to repetitive head impacts. Finally, we discuss future directions for research that will likely lead to a better understanding of the underlying mechanisms separating those who recover from repetitive brain trauma vs. those who go on to develop CTE.
Clinical Features of Repetitive Traumatic Brain Injury and Chronic Traumatic Encephalopathy
Authors: Montenigro Philip H. , Bernick Charles , Cantu Robert C. 
Published: April 2015

AbstractChronic traumatic encephalopathy (CTE) is a neurodegenerative disease characterized by a distinct pattern of hyperphosphorylated tau (p‐tau). Thought to be caused by repetitive concussive and subconcussive injuries, CTE is considered largely preventable. The majority of neuropathologically confirmed cases have occurred in professional contact sport athletes (eg, boxing, football). A recent post‐mortem case series has magnified concerns for the public's health following its identification in six high school level athletes. CTE is diagnosed with certainty only following a post‐mortem autopsy. Efforts to define the etiology and clinical progression during life are ongoing. The goal of this article is to characterize the clinical concepts associated with short‐ and long‐term effects of repetitive traumatic brain injury, with a special emphasis on new clinical diagnostic criteria for CTE. Utilizing these new diagnostic criteria, two cases of neuropathologically confirmed CTE, one in a professional football player and one in a professional boxer, are reported. Differences in cerebellar pathology in CTE confirmed cases in boxing and football are discussed.
Dental fear‐related cognitive vulnerability perceptions, dental prevention beliefs, dental visiting, and caries: a cross‐sectional study in Madrid (Spain)
Authors: Carrillo‐Diaz Maria , Crego Antonio , Armfield Jason M. , Romero Martin 
Published: April 2015

AbstractObjectiveThis study aimed to analyze the role that psychosocial elements may play concerning dental attendance and oral health in children. In particular, we explored the associations among dental fear‐related cognitive vulnerability perceptions, dental prevention beliefs, the pattern of dental visits, and the number of decayed teeth.MethodsA cross‐sectional design was used to collect data from 250 Spanish schoolchildren who completed a questionnaire. Oral health status was evaluated by pediatric dentists. Statistical analyses were mainly based on binary logistic regression and multiple linear regression, which allowed us to test possible associations among variables as well as interaction and mediation effects.ResultsChildren with more vulnerability‐related cognitions (Adj. OR = 0.74 P < 0.05) and more unfavorable dental prevention beliefs (Adj. OR = 1.47 P < 0.01) were less likely to attend the dentist regularly. Moreover, the interaction between dental prevention beliefs and cognitive vulnerability perceptions was associated with more decayed teeth (β = −0.13 P < 0.05). The irregular pattern of dental visit, associated with fearful and unfavorable dental prevention cognitions, accounted for 20% of the effects of these variables on dental caries.ConclusionThe combination of greater cognitive vulnerability‐related perceptions and low awareness of the benefits of dental prevention increased the risk of dental caries. Children with this profile also tended to demonstrate a more inadequate pattern of dental attendance. Preventive oral health programs would benefit from considering the role of children's cognitions on their oral health habits and dental health.
A Bayesian Theory of Sequential Causal Learning and Abstract Transfer
Authors: Lu Hongjing , Rojas Randall R. , Beckers Tom , Yuille Alan L. 
Published: April 2015

AbstractTwo key research issues in the field of causal learning are how people acquire causal knowledge when observing data that are presented sequentially, and the level of abstraction at which learning takes place. Does sequential causal learning solely involve the acquisition of specific cause‐effect links, or do learners also acquire knowledge about abstract causal constraints? Recent empirical studies have revealed that experience with one set of causal cues can dramatically alter subsequent learning and performance with entirely different cues, suggesting that learning involves abstract transfer, and such transfer effects involve sequential presentation of distinct sets of causal cues. It has been demonstrated that pre‐training (or even post‐training) can modulate classic causal learning phenomena such as forward and backward blocking. To account for these effects, we propose a Bayesian theory of sequential causal learning. The theory assumes that humans are able to consider and use several alternative causal generative models, each instantiating a different causal integration rule. Model selection is used to decide which integration rule to use in a given learning environment in order to infer causal knowledge from sequential data. Detailed computer simulations demonstrate that humans rely on the abstract characteristics of outcome variables (e.g., binary vs. continuous) to select a causal integration rule, which in turn alters causal learning in a variety of blocking and overshadowing paradigms. When the nature of the outcome variable is ambiguous, humans select the model that yields the best fit with the recent environment, and then apply it to subsequent learning tasks. Based on sequential patterns of cue‐outcome co‐occurrence, the theory can account for a range of phenomena in sequential causal learning, including various blocking effects, primacy effects in some experimental conditions, and apparently abstract transfer of causal knowledge.
Muscle weakness in children with neurofibromatosis type 1
Authors: Cornett Kayla M D , North Kathryn N , Rose Kristy J , Burns Joshua 
Published: April 2015

AimTo investigate if children with neurofibromatosis type 1 (NF1) have reduced muscle strength compared with children with typical development.MethodMaximal isometric strength of 15 upper and lower limb muscle groups was evaluated in 30 children with NF1 (16 males, 14 females; aged 4–16y) and 30 age‐, sex‐, height‐, and weight‐matched controls using hand‐held dynamometry by a single evaluator. Both the left and right sides were assessed.ResultsChildren with NF1 were significantly weaker than children with typical development across all 15 muscle groups assessed (p<0.05). Apart from elbow flexion, there were no differences between the left and right sides (p>0.05). Magnitude of differences between the children with NF1 compared with the controls ranged from 3% to 43%. Males and females were equally affected.InterpretationThis study shows that children with NF1 have reduced muscle strength compared with children with typical development. This muscle weakness is present from the earliest stages of the disease assessed and persists throughout childhood with no sex difference. These results support recent evidence from mouse studies that NF1 is associated with a primary myopathy.
Efficacy of a long‐acting C‐peptide analogue against peripheral neuropathy in streptozotocin‐diabetic mice
Authors: Jolivalt C. G. , Rodriguez M. , Wahren J. , Calcutt N. A. 
Published: April 2015

AimsTo investigate the efficacy of a pegylated C‐peptide (Peg‐C‐peptide) against indices of peripheral neuropathy in a mouse model of type 1 diabetes and to compare efficacy of this C‐peptide analogue against that of the native molecule.MethodsC57Bl/6 mice were injected with two consecutive doses of streptozotocin (STZ) to induce type 1 diabetes. Mice were treated twice daily with native C‐peptide [0.4–1.3 mg/kg subcutaneously (s.c.)] or twice weekly with Peg‐C‐peptide (0.1–1.3 mg/kg s.c.) for 20 weeks. Motor and sensory nerve conduction velocities, thermal and tactile responses and rate dependent H‐wave depression were assessed after 20 weeks of diabetes. Foot skin intraepidermal fibres and corneal nerves were counted, and sciatic nerve substance P and plasma C‐peptide levels were also determined.ResultsAfter 5 months of STZ‐induced diabetes, mice exhibited significant motor and sensory nerve conduction slowing, thermal hypoalgesia, tactile allodynia and attenuation of rate‐dependent depression of the H reflex. These functional disorders were accompanied by nerve substance P depletion but not loss of small sensory fibres in the hind paw epidermis or the cornea. The efficacy of twice‐daily treatment with native C‐peptide in preventing these disorders was matched or exceeded by twice‐weekly treatment with Peg‐C‐peptide. Both native and Peg‐C‐peptide also increased corneal nerve occupancy in the sub‐basal nerve plexus of control rats.ConclusionsThese data identify actions of C‐peptide against novel and clinically pertinent aspects of diabetic neuropathy in mice and also establish Peg‐C‐peptide as a long‐acting therapeutic method of potential clinical value.
Survival, fecundity, and body mass of Amplicephalus curtulus influenced by ‘Candidatus Phytoplasma ulmi’ (16SrV‐A) infection
Authors: Arismendi Nolberto L. , Carrillo Roberto 
Published: April 2015

AbstractThe leafhopper Amplicephalus curtulus Linnavuori & DeLong (Hemiptera: Cicadellidae) can transmit ‘Candidatus Phytoplasma ulmi’ (16SrV‐A) from a native Chilean shrub, Ugni molinae Turcz. (Myrtaceae), to ryegrasses. A recent study showed that this phytoplasma reduced the total protein content and the activity of detoxifying enzymes in A. curtulus, which could also affect its vector fitness. This study evaluated the effect of ‘Ca. Phytoplasma ulmi’ on the longevity, fecundity, and body mass of A. curtulus. Both females and males were exposed to ‘Ca. Phytoplasma ulmi’‐infected plants for 96 h, whereas a control group remained unexposed. Quartiles from adult emergence to 75% (t75), 50% (t50), and 25% (t25) survival rates were determined for each leafhopper survival distribution. The dry weight was also established at the end of the experiment. The adult lifespan of phytoplasma‐infected males and females was significantly lower than that of the uninfected leafhoppers in quartile survival distributions t50 and t25. The phytoplasma‐infected males and females lived 3 and 4 weeks less than uninfected ones in the last quartile, respectively. Fecundity was established by number of nymphs per female (in four periods) in phytoplasma‐infected and uninfected assays. In general, the weekly pattern of the number of nymphs per phytoplasma‐infected female was lower than that of uninfected leafhoppers; it was 37% lower at the end of the experiment. Phytoplasma‐infected females weighed significantly less (11%) than uninfected individuals. Phytoplasma‐infected males weighed 8% less than uninfected ones, but this difference was not significant. Our data indicated that ‘Ca. Phytoplasma ulmi’ negatively affected the fitness of A. curtulus, and nymphs produced by phytoplasma‐infected females varied over time, which may influence the disease dynamics in nature or in field crops.
Fat and sassy: factors underlying male mating success in a butterfly
Authors: Kehl Tobias , Bensch Julia , Böhm Friederike , Kniepkamp Björn Ole , Leonhardt Vivien , Schwieger Sarah , Fischer Klaus 
Published: April 2015

AbstractTheory predicts that male mating success depends on resource holding potential (RHP), which is reflected by proxies of condition, such as body mass, fat content, strength, or weaponry. In species lacking any physical means to inflict injuries upon combatants, such as butterflies, the factors determining mating success are less clear. Against this background, we explored the determinants of male mating success in the tropical butterfly Bicyclus anynana Butler (Lepidoptera: Nymphalidae: Satyrinae), by comparing physiological, immunological, and morphological traits between winning and losing males. Our results showed that successful males are characterized by a better flight performance, evidenced by having longer wings, a heavier thorax, a lighter abdomen, a higher fat content, and higher phenoloxidase expression levels than their unsuccessful counterparts, when being compared after their first mating. Males that won three consecutive trials against the same combatant were also characterized by a better flight performance, having larger forewings, a higher body mass, and a higher fat content. Thus, successful males were larger and in better condition than unsuccessful ones. Strikingly, many differences found indicated an enhanced flight performance for the former, which we suggest ultimately plays the key role for male mating success in B. anynana. As fat is the main energy source for flying insects, being crucial to flight endurance and in turn presumably to male mating success, it may represent a key determinant at the proximate level.
Short‐term plasticity regulates the excitation/inhibition ratio and the temporal window for spike integration in CA1 pyramidal cells
Authors: Bartley Aundrea F. , Dobrunz Lynn E. 
Published: April 2015

AbstractMany neurodevelopmental and neuropsychiatric disorders involve an imbalance between excitation and inhibition caused by synaptic alterations. The proper excitation/inhibition (E/I) balance is especially critical in CA1 pyramidal cells, because they control hippocampal output. Activation of Schaffer collateral axons causes direct excitation of CA1 pyramidal cells, quickly followed by disynaptic feedforward inhibition, stemming from synaptically induced firing of GABAergic interneurons. Both excitatory and inhibitory synapses are modulated by short‐term plasticity, potentially causing dynamic tuning of the E/I ratio. However, the effects of short‐term plasticity on the E/I ratio in CA1 pyramidal cells are not yet known. To determine this, we recorded disynaptic inhibitory postsynaptic currents and the E/I ratio in CA1 pyramidal cells in acute hippocampal slices from juvenile mice. We found that, whereas inhibitory synapses had paired‐pulse depression, disynaptic inhibition instead had paired‐pulse facilitation (≤ 200‐ms intervals), caused by increased recruitment of feedforward interneurons. Although enhanced disynaptic inhibition helped to constrain paired‐pulse facilitation of excitation, the E/I ratio was still larger on the second pulse, increasing pyramidal cell spiking. Surprisingly, this occurred without compromising the precision of spike timing. The E/I balance regulates the temporal spike integration window from multiple inputs; here, we showed that paired‐pulse stimulation can broaden the spike integration window. Together, our findings show that the combined effects of short‐term plasticity of disynaptic inhibition and monosynaptic excitation alter the E/I balance in CA1 pyramidal cells, leading to dynamic modulation of spike probability and the spike integration window. Short‐term plasticity is therefore an important mechanism for modulating signal processing of hippocampal output.
Expression of the postsynaptic scaffold PSD‐95 and development of synaptic physiology during giant terminal formation in the auditory brainstem of the chicken
Authors: Goyer David , Fensky Luisa , Hilverling Anna Maria , Kurth Stefanie , Kuenzel Thomas 
Published: April 2015

AbstractIn the avian nucleus magnocellularis (NM) endbulb of Held giant synapses develop from temporary bouton terminals. The molecular regulation of this process is not well understood. Furthermore, it is unknown how the postsynaptic specialization of the endbulb synapses develops. We therefore analysed expression of the postsynaptic scaffold protein PSD‐95 during the transition from bouton‐to‐endbulb synapses. PSD‐95 has been implicated in the regulation of the strength of glutamatergic synapses and could accordingly be of functional relevance for giant synapse formation. PSD‐95 protein was expressed at synaptic sites in embryonic chicken auditory brainstem and upregulated between embryonic days (E)12 and E16. We applied immunofluorescence staining and confocal microscopy to quantify pre‐and postsynaptic protein signals during bouton‐to‐endbulb transition. Giant terminal formation progressed along the tonotopic axis in NM, but was absent in low‐frequency NM. We found a tonotopic gradient of postsynaptic PSD‐95 signals in NM. Furthermore, PSD‐95 immunosignals showed the greatest increase between E12 and E15, temporally preceding the bouton‐to‐endbulb transition. We then applied whole‐cell electrophysiology to measure synaptic currents elicited by synaptic terminals during bouton‐to‐endbulb transition. With progressing endbulb formation postsynaptic currents rose more rapidly and synapses were less susceptible to short‐term depression, but currents were not different in amplitude or decay‐time constant. We conclude that development of presynaptic specializations follows postsynaptic development and speculate that the early PSD‐95 increase could play a functional role in endbulb formation.
Variance Distribution in Sibling Relationships: Advantages of Multilevel Modeling Using Full Sibling Groups
Authors: Marciniak Karyn 
Published: April 2015

The majority of research on sibling relationships has investigated only one or two siblings in a family, but there are many theoretical and methodological limitations to this single dyadic perspective. This study uses multiple siblings (541 adults) in 184 families, where 96 of these families had all siblings complete the study, to demonstrate the value in including full sibling groups when conducting research on sibling relationships. Two scales, positivity and willingness to sacrifice, are evaluated with a multilevel model to account for the nested nature of family relationships. The distribution of variance across three levels: relationship, individual, and family are computed, and results indicate that the relationship level explains the most variance in positivity, whereas the individual level explains the majority of variance in willingness to sacrifice. These distributions are affected by gender composition and family size. The results of this study highlight an important and often overlooked element of family research: The meaning of a scale changes based on its distribution of variance at these three levels. Researchers are encouraged to be cognizant of the variance distribution of their scales when studying sibling relationships and to incorporate more full sibling groups into their research methods and study design.
Cyanobacterial dynamics in shallow Lake Apopka (Florida, U.S.A.) before and after the shift from a macrophyte‐dominated to a phytoplankton‐dominated state
Authors: Waters Matthew N. , Schelske Claire L. , Brenner Mark 
Published: April 2015

Summary

Paleolimnological data were used to reconstruct the primary producer history of shallow, hyper‐eutrophic Lake Apopka, Florida, U.S.A. Lake Apopka changed from a macrophyte‐dominated state to a phytoplankton‐dominated state in 1947. It has remained phytoplankton‐dominated despite efforts to re‐establish clear‐water conditions and submersed aquatic plants.

Photosynthetic pigments, organic matter and nutrients (C, N, P) were analysed in a 4.28‐m sediment core that spans the past c. 8000 years. Our objectives were to: (i) reconstruct the primary producer history of Lake Apopka throughout its c. 8000‐year existence, (ii) determine whether the cyanobacterial dominance established in 1947 in Lake Apopka is the only period of cyanobacterial dominance in the lake's history and (iii) relate changes in the cyanobacterial community to known human impacts and recent management efforts.

Lake Apopka possessed a macrophyte‐dominated primary producer community throughout most of its Holocene history, with diatoms, green algae and some cyanobacteria characterising the non‐macrophyte, primary producer component of the community.

Since 1947, however, higher plants have been virtually absent in the lake and cyanobacteria have dominated the primary producer community, marking the first time that cyanobacteria have played such an important role in the lake. The cyanobacterial community itself has undergone multiple changes since 1947, confounding management efforts that have focused on a single driver of the primary producer community, that is phosphorus.