bluuebunny/crossref_metadata_2025_split huggingface dataset:
The evolution of genomic imprinting: costs, benefits and long‐term consequences
Authors: Holman Luke , Kokko Hanna 
Published: October 2013

ABSTRACTGenomic imprinting refers to a pattern of gene expression in which a specific parent's allele is either under‐expressed or completely silenced. Imprinting is an evolutionary conundrum because it appears to incur the costs of diploidy (e.g. presenting a larger target than haploidy to mutations) while foregoing its benefits (protection from harmful recessive mutations). Here, we critically evaluate previously proposed evolutionary benefits of imprinting and suggest some additional ones. We discuss whether each benefit is capable of explaining both the origin and maintenance of imprinting, and examine how the different benefits interact. We then outline the many costs of imprinting. Simple models show that circulating deleterious recessives can prevent the initial spread of imprinting, even if imprinting would be evolutionarily stable if it could persist long enough to purge these. We also show that imprinting can raise or lower the mutation load, depending on the selective regime and the degree of dominance. We finish by discussing the population‐level consequences of imprinting, which can be both positive and negative. Imprinting offers many insights into evolutionary conflict, the interaction between individual‐ and population‐level fitness effects, and the ‘gene's‐eye view’ of evolution.
The Big Difference a Small Island Can Make: How Jamaican Adolescents Are Advancing Acculturation Science
Authors: Ferguson Gail M. 
Published: October 2013

AbstractNew research with Jamaican adolescents has brought acculturation science into closer accord with two 21st‐century cultural realities: (a) multicultural destination societies for immigrant families and (b) intercultural contact among nonimmigrant families via modern globalization mechanisms. In this article, I review two theoretical expansions to the traditional conceptualization of acculturation (i.e., tridimensional acculturation and remote acculturation) along with supporting empirical evidence among Jamaican adolescents in the United States and on the Caribbean island. First, bidimensional acculturation lenses are exchanged for tridimensional ones to capture the acculturation of immigrant youth for whom three cultural dimensions are relevant. Second, acculturation pathways are expanded to include modern indirect and/or intermittent intercultural contact for nonimmigrant youth. Tridimensional and remote acculturation may be modern mechanisms by which today's and tomorrow's adolescents produce their own development. These advances reveal new avenues to investigate adolescent acculturation and adaptation in their increasingly complex cultural neighborhoods.
Role of acid sphingomyelinase in the regulation of mast cell function
Authors: Yang W. , Schmid E. , Nurbaeva M. K. , Szteyn K. , Leibrock C. , Yan J. , Schaller M. , Gulbins E. , Shumilina E. , Lang F. 
Published: October 2013

SummaryBackgroundDegranulation of mast cells is stimulated by store‐operated Ca2+‐entry (SOCE). In other cell types, Ca2+‐entry is modified by ceramide. Exogenously added ceramide has been shown to trigger mast cell apoptosis. Effects of endogenously produced ceramide in mast cells remained, however, elusive. Ceramide may be produced from sphingomyelin by acid sphingomyelinase (Asm).ObjectiveThis study explored the impact of Asm on mast cell functions.MethodsMast cells were isolated from bone marrow (BMMCs) or peritoneal lavage of gene‐targeted mice lacking Asm (asm−/−) and their wild‐type littermates (asm+/+). BMMC maturation and apoptosis‐associated annexin V binding were determined by flow cytometry. Asm activity was assessed enzymatically, cytosolic Ca2+ activity ([Ca2+]i) utilizing Fura‐2 fluorescence, current across the cell membrane by whole‐cell patch clamp, degranulation from hexosaminidase‐release and migration utilizing a transwell chamber. In vivo anaphylaxis was derived from decrease in body temperature.ResultsPeritoneal mast cell number, BMMC phenotype, spontaneous BMMC apoptosis as well as BMMC CD117, CD34 and FcεRI expression were similar in both genotypes. In asm+/+ BMMCs, stimulation with antigen resulted in a fast ~2.5‐fold increase in Asm activity. Release of Ca2+ from internal stores and hence several Ca2+‐dependent functions were strongly impaired in asm−/− BMMCs. Thus, antigen‐induced increase in [Ca2+]i in IgE‐sensitized cells, antigen‐ but not ionomycin‐induced currents through Ca2+‐activated K+‐channels (KCa3.1), IgE/antigen‐triggered β‐hexosaminidase release, and antigen‐induced migration were all lower in asm−/− BMMCs than in asm+/+ BMMCs. Pharmacological inhibition of Asm by amitriptyline (500 nm, 3 h) in asm+/+ BMMCs similarly decreased antigen‐induced increase in [Ca2+]i, KCa3.1 currents, ß‐hexosaminidase release and migration. The decrease in body temperature upon the induction of systemic anaphylaxis was significantly less pronounced in asm−/− mice than in asm+/+ mice, an observation pointing to in vivo significance of Asm.Conclusions and Clinical RelevanceAsm is a novel, powerful regulator of mast cell function and thus a potential target in the treatment of allergic reactions.
Protein kinase C‐η polymorphism rs2230500 does not confer disease susceptibility to multiple sclerosis or neuromyelitis optica
Authors: Kawano Yuji , Matsushita Takuya , Cui Yi Wen , Isobe Noriko , Yoshimura Satoshi , Yonekawa Tomomi , Masaki Katsuhisa , Yamasaki Ryo , Murai Hiroyuki , Kira Jun‐ichi 
Published: October 2013

AbstractObjectivesTo determine whether the non‐synonymous 1425G/A polymorphism (rs2230500), an Asian‐specific single nucleotide polymorphism that increases the kinase activity and affects the function of immune cells, of the protein kinase C‐η gene (PRKCH) confers the risk of developing idiopathic demyelinating diseases of the central nervous system in a Japanese population.MethodsBlood samples were collected from 96 multiple sclerosis (MS) patients, 52 neuromyelitis optica (NMO)/NMO spectrum disorder (NMOSD) patients and 151 healthy controls. The polymorphism rs2230500 was genotyped by sequencing.ResultsNo significant association was observed between the PRKCH rs2230500 polymorphism and the risk of either MS or NMO/NMOSD. Clinical characteristics were also unaffected by the rs2230500 status.ConclusionsAlthough the possibility that PRKCH has some effect on MS and NMO/NMOSD risk cannot be completely excluded because of the small study sample size, the polymorphism rs2230500 did not appear to confer disease susceptibility to MS or NMO/NMOSD in this Japanese population.
Association of transalveolar sinus floor elevation, platelet rich plasma, and short implants for the treatment of atrophied posterior maxilla
Authors: Anitua Eduardo , Alkhraist Mohammad H. , Piñas Laura , Orive Gorka 
Published: October 2013

AbstractObjectivesAssess the efficiency of transalveolar sinus floor augmentation in association with platelet rich plasma and short implants for the treatment of atrophied edentulous maxilla with a residual bone height (RBH) <5 mm.Materials and methodsAtrophied posterior maxilla was treated with transalveolar sinus floor augmentation performed with conventional bone drills and autologous platelet concentrate. The space created below the Schneiderian membrane was filled with platelet rich plasma alone or in combination with a bone graft and followed by the insertion of short implants. Surgical complications, implant survival, and marginal bone loss were evaluated during the follow‐up period.ResultsForty‐eight patients (average age: 55.98 ± 8.71 years) with 61 short implants were treated in this study. Schneiderian membrane perforation occurred in one maxillary sinus, and the initial RBH of 4.15 ± 0.53 mm was increased to 8.86 ± 1.60 mm. There was no significant difference between the grafting materials with respect to the gained bone height. The mean follow‐up time of the implants was 10.81 ± 5.87 months (range: 2–28 months) since loading. The average bone loss was 0.59 ± 0.12 mm (loading time <6 months), 0.62 ± 0.16 mm (loading time between 6 and 12 months), and 1.00 ± 0.45 mm (loading time higher than 12 months). The use of wide implants was the only parameter that decreases significantly the marginal bone loss. Two implant failures occurred before loading, and the cumulative implant survival rate was 96.7%.ConclusionsThe proposed treatment protocol for transalveolar sinus floor augmentation could be efficient in the treatment of severe atrophy in the maxilla.
Differences in degradation behavior of two non‐cross‐linked collagen barrier membranes: an in vitro and in vivo study
Authors: Bozkurt Ahmet , Apel Christian , Sellhaus Bernd , van Neerven Sabien , Wessing Bastian , Hilgers Ralf‐Dieter , Pallua Norbert 
Published: October 2013

AbstractObjectivesCollagen barrier membranes are used in guided bone regeneration/guided tissue regeneration because of their excellent bio‐ and cytocompatibility. However, they are considered to have limitations in clinical outcome because of rapid and unpredictable degradation profiles. The aim of this study was to investigate the degradation behavior of two porcine‐based, non‐cross‐linked collagen membranes in vitro and in vivo.Materials and MethodsRemaix™ (RX; Matricel GmbH, Herzogenrath, Germany) and Bio‐Gide® (BG; Geistlich Pharma AG, Wolhusen, Switzerland) membranes were characterized by testing mechanical strength, denaturation temperature, enzymatic degradation and hydroxyproline content in vitro (n = 5 up to 16). Thereafter, both membranes were implanted subcutaneously in rats (n = 20) for up to 20 weeks to investigate tissue compatibility with respect to membrane thickness.ResultsBG contained a significant higher hydroxyproline content compared with RX, but RX showed a higher stress at break (dry: 11.4 (SD 2.9) vs. 5.5 (SD 1.5) N/mm²), higher suture retention (wet: 5.6 (SD 1.3) vs. 2.7 (SD 0.7) N), increased denaturation temperature (55.1 (SD 1) vs. 49.4 (SD 0.6)°C) and an almost twofold reduction in degradation rate (15.6% (SEM 1.3)/h vs. 24.8% (SEM 2.9)/h) in vitro. In the rat model, both membranes showed excellent tissue compatibility without signs of inflammatory reactions. Shortly after implantation, RX and BG showed moderate infiltration of mononuclear cells that appeared not to be influenced by the surface texture of the membranes. In the histomorphometric analysis, both membranes showed significant different thickness over the 20 weeks period (P = 0.0002). Although the thickness remained almost stable during the first 9 weeks after implantation, after 20 weeks, the thickness of RX decreased only slightly, whereas BG showed a thickness loss of around 50% and stronger degradation than RX. Therefore, the higher stability of RX against biodegradation found in vitro was confirmed in the animal study.ConclusionThis study shows differences in the biodegradation characteristics of two non‐cross‐linked collagen membranes in vitro and in vivo. Whether the higher stability of RX is of clinical relevance should be analyzed in future clinical investigations.
Intercolony movement of pre‐breeding seabirds over oceanic scales: implications of cryptic age‐classes for conservation and metapopulation dynamics
Authors: Bicknell Anthony W. J. , Knight Mairi E. , Bilton David T. , Campbell Maria , Reid James B. , Newton Jason , Votier Stephen C. 
Published: October 2013

AbstractAimDemographic linkage between subpopulations plays a critical role in population processes. Metapopulation dynamics, however, remains one of the most poorly understood aspects of population biology. This is especially true for small, pelagic seabirds because their discrete subpopulations are located on offshore islands, separated by vast areas of open ocean, making monitoring logistically challenging. Seabird populations often contain large numbers of immature pre‐breeders that may be important for subpopulation connectivity and demography, but are poorly studied. Here we provide evidence for intercolony movement of pre‐breedingLeach's storm‐petrelsOceanodroma leucorhoaamong three colonies spanning theNorthAtlanticOcean. We discuss their influence on metapopulation dynamics and the extinction risk of a subpopulation under threat from extreme predation.LocationNorthAtlanticOceanIslands (Scotland,Canada &Iceland).MethodsWe use a novel application ofBayesian stable isotope mixing models to infer recent movement of pre‐breeding birds between three major breeding populations in theNorthAtlantic. Carbon and nitrogen stable isotope values from breeding birds (central place foragers) sampled at each colony were used as model sources and pre‐breeding birds as model mixtures.ResultsOf 134 pre‐breeding Leach's storm‐petrels sampled at three colonies across theNorthAtlantic, five had isotope mixing model estimates dissimilar (< 25%) to their colony of capture and were instead isotopically similar to another breeding region. Nineteen further pre‐breeders had highly mixed signatures (< 50% for the colony of capture), indicating possible recent movement between colonies.Main conclusionsOur findings provide evidence for interpopulation connectivity of pre‐breedingLeach's storm‐petrels among colonies spanning theNorthAtlantic. These results highlight the significance of cryptic young age‐classes in metapopulation dynamics and the demographic processes. Moreover, they provide us with a better understanding of how one subpopulation remains extant, despite experiencing extreme predation rates.
Live/Real Time Three‐Dimensional Transesophageal Echocardiographic Assessment of Ventricular Septal Volume and Mass before and after Myectomy in Hypertrophic Cardiomyopathy
Authors: Sadat Kamel , Diddi Hari Prakash , Klas Berthold , Asaad Ayman Haj , Çekirdekçi Elif İjlal , Sungur Aylin , Sudhakar Selvin , Cain Matthew , Kamal Arshad , Nanda Navin C. 
Published: October 2013

Hypertrophic cardiomyopathy (HCM) is the most common genetically transmitted cardiomyopathy. In patients resistant to medical management, myectomy is the surgical procedure of choice to reduce the symptoms of left ventricular outflow obstruction. Two‐dimensional transesophageal echocardiography (2DTEE) has become part of the operative procedure by decreasing the incidence of postoperative complications. However, because of the three‐dimensional geometry of left ventricular outflow tract, it is unable to comprehensively assess the location and severity of the obstruction and to provide accurate guidance during myectomy. In this study, 10 patients with HCM underwent live/real time three‐dimensional transesophageal echocardiography (3DTEE) intra‐operatively to measure the volume of the resected septum. This volume correlated well with the volume of the resected septal muscle directly obtained using a graduating cylinder containing water (r = 0.9, P < 0.000). 3DTEE may be potentially used as an adjunct to guide the surgeon in performing an adequate myectomy with a lower incidence of residual obstruction and complications such as an iatrogenic ventricular septal defect.
Examining growth rate and starvation endurance in pit‐building antlions from Mediterranean and desert regions
Authors: ROTKOPF RON , OVADIA OFER 
Published: October 2013

Stressful or stochastic environments may have significant selective effects, leading to increased plasticity or stress resistance. Starvation is a type of stress commonly encountered among organisms inhabiting stochastic environments. Indeed, starvation endurance is an important trait, especially in sit‐and‐wait predators, which experience frequent fluctuations in prey arrivals because of their limited mobility.
Differences in starvation endurance between antlions originating from Mediterranean (benign and predictable) and desert (harsher and stochastic) regions were investigated by exposing them to starvation in a fully factorial experiment using climate chambers simulating Mediterranean or desert climatic conditions.
A trade‐off between growth rate and starvation endurance was also investigated by feeding the antlions at two different frequencies pre‐starvation. Additionally, the existence of growth compensation was tested for by measuring relative growth rate when feeding was resumed post‐starvation.
Population of origin did not significantly affect rates of body mass loss during starvation or relative growth rates when feeding was resumed. Antlions that were fed less frequently during the feeding phase lost mass faster during the starvation phase, but grew faster during the compensation phase.
This study emphasises the importance of testing responses to stress when investigating life‐history trade‐offs. Some phenotypic differences between populations might be apparent only when exposing the experimental organisms to external stress. Conversely, phenotypic differences apparent under stress‐free conditions might be masked by the effects of the stress factor. Adopting such an integrative approach allows elucidation of the level of plasticity in response to stress in different populations.
Short‐term effects of biochar on soil heavy metal mobility are controlled by intra‐particle diffusion and soil pH increase
Authors: Rees F. , Simonnot M. O. , Morel J. L. 
Published: October 2013

SummaryBiochar, the solid product of biomass pyrolysis, can be used as a soil amendment to stabilize metals in contaminated soils. The effects of biochar on the mobility of metals in soils are, however, poorly understood. To identify the predominant processes, we focused on (i) a possible kinetic limitation by transport in biochar particles, (ii) the evolution of biochar mineral phases and (iii) the effect of biochar on soil pH. Batch experiments were conducted to measure the sorption kinetics of copper (Cu), cadmium (Cd) and nickel (Ni) and the sorption‐desorption isotherms for lead (Pb), Cu, Cd, zinc (Zn) and Ni in a wood‐derived biochar. Sorption data were then compared with extraction test results using biochar with one acidic and one basic soil contaminated by Zn, Cd and Pb. Kinetic results showed that biochar particle sizes controlled metal sorption rate despite a similar specific surface area, which indicated a limitation by intra‐particle diffusion. Isotherms showed a partially reversible sorption to biochar following the order Pb > Cu > Cd ≥ Zn > Ni, which we explained primarily by the (co)precipitation of metals or their adsorption on specific biochar mineral phases. Effective metal immobilization was observed with biochar in both contaminated soils but could not be predicted from the sorption isotherms. This immobilization appeared to be governed by the soil pH increase, which induced a greater retention of metals on soil particles. Short‐term effects of biochar on contaminated soils may therefore be controlled by diffusion in biochar particles and by soil alkalinization processes.
Moving beyond methods: the need for a diverse programme in climate change research
Authors: Thompson Ross M. , Beardall John , Beringer Jason , Grace Mike , Sardina Paula 
Published: October 2013

AbstractUnderstanding effects of climate change on ecosystems will require a diverse range of approaches. We proposed using downscaled climate models to generate realistic weather scenarios as experimental treatments. Kreyling et al. propose a gradient approach to determine the shape of response functions. These approaches are different, but highly complementary.
CPP‐115, a vigabatrin analogue, decreases spasms in the multiple‐hit rat model of infantile spasms
Authors: Briggs Stephen W. , Mowrey Wenzhu , Hall Charles B. , Galanopoulou Aristea S. 
Published: October 2013

SummaryObjectiveInfantile spasms (IS) have poor outcomes and limited treatment options, including vigabatrin, a γ‐aminobutyric acid (GABA) aminotransferase inactivator. Vigabatrin has been associated with retinal toxicity. A high affinity vigabatrin analogue (CPP‐115; Catalyst Pharmaceutical Partners, Inc., Coral Gables, FL, U.S.A.) has shown lower risk of retinal toxicity. Here, we test the efficacy of CPP‐115 in reducing spasms and its tolerability in the multiple‐hit rat model of IS, in which daily vigabatrin reduced spasms for only one day, but was not well tolerated.MethodsMale rats were treated with the protocol of the multiple‐hit model of IS on postnatal day 3 (PN3). Using a randomized, blinded, vehicle‐controlled, dose‐response study design, CPP‐115 (0.1, 1, or 5 mg/kg intraperitoneally [i.p.]) or vehicle was given daily (PN4–12) or as a single injection (PN7) after spasm onset. Intermittent video‐ or video‐electroencephalography (EEG) monitoring was done. Secondary end points included the following: daily weights, survival, performance on open field activity, surface righting time, and negative geotaxis (PN3–20), horizontal bar (PN13–20), and Barnes maze (PN16–19). Statistics used a linear mixed model of raw or normalized log‐transformed data, taking into account the repeated observations on each animal.ResultsThe lower CPP‐115 doses (0.1–1 mg/kg/day, PN4–12) reduced spasms between PN6 and 7 without increasing mortality. CPP‐115 at 5 mg/kg/day (PN4–12) reduced spasms earlier (PN5), but was eventually lethal. A single CPP‐115 injection (1 mg/kg, i.p.) decreased electroclinical spasms acutely but transiently. CPP‐115 transiently improved the probability to >50% reduction of spasms, but did not accelerate spasm cessation. CPP‐115 did not alter neurodevelopmental outcomes or visuospatial learning.SignificanceWe provide proof‐of‐concept evidence that CPP‐115, a vigabatrin analogue, decreases spasms in the multiple‐hit rat model of IS at considerably lower and better tolerated doses than vigabatrin did in our previous studies. Further optimization of the treatment protocol is needed. CPP‐115 may be a promising new candidate treatment for IS with better tolerability than vigabatrin.
Dysembryoplastic neuroepithelial tumors: A model for examining the effects of pathology versus seizures on cognitive dysfunction in epilepsy
Authors: Baxendale Sallie , Donnachie Elizabeth , Thompson Pamela , Sander Josemir W. 
Published: October 2013

SummaryPurposeDysembryoplastic neuroepithelial tumors (DNTs) provide a unique model for studying the effects of seizures on cognitive development. Epilepsy and antiepileptic medications are prominent features in the lives and schooling of people who develop seizures in childhood. People with an adult onset share the same underlying brain pathology, but their childhood development is unaffected by seizures. Therefore, DNTs provide a model to examine the specific influence of seizures and their treatment on cognitive development, over and above the effects of the underlying pathology in epilepsy.MethodsWe examined the neuropsychological characteristics of 56 adults with DNT and medically intractable epilepsy (mean age 32.7 years). Twenty‐two adults (39%) had an age of onset of epilepsy before the age of 12 years (childhood‐onset group). Scores on tests of intelligence (Verbal IQ and Performance IQ), reading, working memory, verbal learning, verbal recall, visual learning, and expressive and receptive language ability were analyzed.Key FindingsThere were no significant localization effects (right vs. left vs. extratemporal) on any of the neuropsychological test scores. In the group as a whole, the neuropsychological test scores were significantly lower than healthy, age‐matched controls on measures of Verbal IQ (p < 0.01), naming p < 0.01, verbal learning (p < 0.01), and working memory (p < 0.05). The childhood‐onset group had significantly lower scores on the measures of Verbal IQ (p < 0.01), Performance IQ (p < 0.05), reading (p < 0.05), naming (p = 0.05), and verbal retention (p < 0.05) than those with an onset of seizures at the age of 12 or older.SignificanceThe traditional pattern of lateralized memory deficits seen in people with hippocampal sclerosis may not be present in people with temporal lobe epilepsy associated with a DNT. The presence of seizures and their treatment in early childhood may adversely influence the development of these core cognitive abilities, resulting in patterns of cognitive deficits that remain apparent in adulthood.