bluuebunny/crossref_metadata_2025 huggingface dataset:
Exceptionally long, narrow drumlins formed in subglacial cavities, North Dakota
Authors: BLUEMLE JOHN P. , LORD MARK L. , HUNKE NATHAN T.
Published: September 2009

An array of about 200 exceptionally long and narrow drumlins occurs in north‐central North Dakota. The most prominent of the drumlins is 27 km long, and their average length is between 2 km and 3 km. The drumlin field is closely associated with, and occurs immediately up‐glacier from, an extensive area of ice‐thrust topography. Most of the drumlin ridges have small glacier‐thrust masses at their heads. Internal structures are complex, but typically include large numbers of gravity faults, which dip away from the center of the drumlin ridges. Materials contained in the drumlins were transported from higher pressure areas beneath the glacier, inward toward lower pressure areas (cavities) by flowing, thrusting, squeezing and other processes. The close and systematic association of the long drumlins with nearby areas of ice‐thrust topography indicates a genetic tie; conditions that caused the glacier to form large ice thrusts also contributed to drumlin formation. Major factors involved in the formation of the drumlins were high porewater pressures in interbedded permeable and impermeable materials beneath a thin, swiftly flowing glacier, and the presence of areas of frozen ground near the margin of the glacier.
Younger Dryas‐age readvance of Laurentide ice into the Champlain Sea
Authors: LASALLE PIERRE , SHILTS WILLIAM W.
Published: September 2009

Occurrences ofBalanus hameri‐bearingdiamicts described in this paper and pertinent (Balanusplates and pelecypods shells)14C dates suggest that there was glacial activity in the Champlain Sea basin between 11,000 BP and 10,400 BP and that this activity can be ascribed to a climatic cooling episode correlative with the Younger Dryas of the late‐glacial sequence of northeastern Europe.
Glacigenic deposits of the Central Deep: a key to the Late Quaternary evolution of the eastern Barents Sea
Authors: GATAULLIN VALERY , POLYAK LEONID , EPSTEIN OLEG , ROMANYUK BORIS
Published: September 2009

Sparker and shallow drilling data indicate that the Quaternary deposits in the Central Deep of the Barents Sea are mainly composed of glacigenic sediments. They comprise basal till and proximal and distal glaciomarine sediments deposited during the last glacial cycle. Apparent glaciotectonic features imply strong glacial erosion of Mesozoic bedrock. The general ice movement is assumed to have been from off Novaya Zemlya and it is concluded that the whole eastern Barents Sea was covered by the Late Weichselian ice‐sheet.
Physical signatures of ice advance in a Younger Dryas ice‐contact delta, Troms, northern Norway: implications for glacier‐terminus history
Authors: LØNNE IDA
Published: September 2009

The depositional history of an ice‐contact delta in Sørfjorden has been reconstructed, based on two sections, 100 and 900 m long. Five major sedimentary facies have been distinguished within the delta's foreset, and their geometry and spatial organization have been mapped in the outcrops through the use of photographs. Facies 1 comprises chaotically bedded coarse clastics; facies 2 comprises sets of high‐angle clinoforms; facies 3 comprises sets of low‐angle sandy clinoforms; facies 4 comprises sets of hummocky sandy clinoforms and facies 5 comprises sets of low‐angle to subhorizontal sandy and muddy clinoforms. The glacier advanced at least 500 m during the formation of the foreset sequence. Six minor halts during this advance are indicated. The study puts new constraints on the history of the Younger Dryas ice advance in the region, including local palaeogeography, ice‐front dynamics and fjord‐fill sediment stratigraphy.
Role of the elastin receptor complex (S‐Gal/Cath‐A/Neu‐1) in skin repair and regeneration
Authors: Antonicelli Frank , Bellon Georges , Lorimier Sandrine , Hornebeck William
Published: September 2009

Impaired elastic fiber assembly constitutes one major problem in skin wound healing. Recent data indicate that a ternary complex involving a splicing form of β‐galactosidase associated with cathepsin‐A and neuraminidase‐1 directs the transport of tropoelastin to the fibroblast plasma membrane and participates in the deposition of the elastin precursor onto a microfibrillar scaffold. In addition, this elastin receptor complex is ubiquitously expressed and also acts as a true receptor for elastin‐derived peptides produced during the initial stage of wound repair following elastase‐mediated proteolysis action. Among the peptides generated, those having a x.G.x.x.P.G. motif upregulate (i) keratinocyte migration, (ii) endothelial cell angiogenic phenotype, (iii) fibroblast proliferation, and (iv) induction of the expression of matrix metalloproteinases, type I collagen, and tropoelastin. All of these properties could accelerate the different stages of wound repair. Elastin‐derived peptides from a chemical or a proteolytic digest of insoluble elastin alone or linked to the collagen scaffold significantly improve skin wound healing and dermal regeneration in vivo in several animal models. Such a beneficial influence has been recently extended to the treatment of burn patients. In this respect, recent investigations have focused on the design of elastin‐derived peptides or elastin‐building blocks, as obtained from peptide chemistry or by genetic engineering, to elaborate biocompatible elastin peptides, which are considered as ideal biomaterials for “catalyzing” skin repair and regeneration following injury.
Preliminary development of a diabetic foot ulcer database from a wound electronic medical record: A tool to decrease limb amputations
Authors: Golinko Michael S. , Margolis David J. , Tal Adit , Hoffstad Ole , Boulton Andrew J. M. , Brem Harold
Published: September 2009

Our objective was to create a practical standardized database of clinically relevant variables in the care of patients with diabetes and foot ulcers. Numerical clinical variables such as age, baseline laboratory values, and wound area were extracted from the wound electronic medical record (WEMR). A coding system was developed to translate narrative data, culture, and pathology reports into discrete, quantifiable variables. Using data extracted from the WEMR, a diabetic foot ulcer‐specific database incorporated the following tables: (1) demographics, medical history, and baseline laboratory values; (2) vascular testing data; (3) radiology data; (4) wound characteristics; and (5) wound debridement data including pathology, culture results, and amputation data. The database contains variables that can be easily exported for analysis. Amputation was studied in 146 patients who had at least two visits (e.g., two entries in the database). Analysis revealed that 19 (13%) patients underwent 32 amputations (nine major and 23 minor) in 23 limbs. There was a decreased risk of amputation, 0.87 (0.78, 1.00), using a proportional hazards model, associated with an increased number of visits and entries in the WEMR. Further analysis revealed no significant difference in age, gender, HbA1c%, cholesterol, white blood cell count, or prealbumin at baseline, whereas hemoglobin and albumin were significantly lower in the amputee group (p<0.05) than the nonamputee group. Fifty‐nine percent of amputees had histological osteomyelitis based on operating room biopsy vs. 45% of nonamputees. In conclusion, tracking patients with a WEMR is a tool that could potentially increase patient safety and quality of care, allowing clinicians to more easily identify a nonhealing wound and intervene. This report describes a method of capturing data relevant to clinical care of a patient with a diabetic foot ulcer, and may enable clinicians to adapt such a system to their own patient population.
Differential expression of matrix metalloproteinases and tissue inhibitors of metalloproteinases in anterior cruciate ligament and medial collateral ligament fibroblasts after a mechanical injury: Involvement of the p65 subunit of NF‐κB
Authors: Tang Zhenyu , Yang Li , Xue Ruyue , Zhang Jin , Wang Yequan , Chen Peter C. , Sung K. L. Paul
Published: September 2009

The anterior cruciate ligament (ACL) is known to have a poor healing ability, especially in comparison with the medial collateral ligament, which can heal relatively well. In this study, we detected significant increases in the mRNA levels of multiple matrix metalloproteinases (MMPs) (MMP‐1, ‐2, ‐7, ‐9, ‐11, ‐14, ‐17, ‐21, ‐23A, ‐24, ‐25, ‐27, and ‐28) and tissue inhibitors of metalloproteinases (TIMPs) (TIMP‐1, ‐2, ‐3, and ‐4) in ACL fibroblasts after an in vitro injury with an equi‐biaxial stretch chamber. However, only some MMPs (MMP‐7, ‐9, ‐14, ‐21, and ‐24) showed increases in injured medial collateral ligament fibroblasts, and to a much lesser degree than that observed in the injured ACL fibroblasts. Zymography revealed a 6.3‐fold increase of MMP‐2 activity in injured ACL but not medial collateral ligament fibroblasts, which agrees with the global MMP activities assay. Bay‐11 and curcumin can significantly decrease MMP‐2 activities to 13% and 29% in injured ACL fibroblasts, respectively, which implies the involvement of p65 subunits of nuclear factor κB and AP‐1 pathways. Furthermore, Bay‐11 can decrease the global MMP activity released from injured ACL fibroblasts in a dose‐dependent manner. In summary, the differential expression and activities of MMPs might help to explain the poor healing ability of ACL, and the p65 subunit of nuclear factor κB might be a potential target to facilitate the ACL repair.
Differences in collagen architecture between keloid, hypertrophic scar, normotrophic scar, and normal skin: An objective histopathological analysis
Authors: Verhaegen Pauline D. H. M. , Van Zuijlen Paul P. M. , Pennings Noor M. , Van Marle Jan , Niessen Frank B. , Van Der Horst Chantal M. A. M. , Middelkoop Esther
Published: September 2009

Normotrophic, hypertrophic, and keloidal scars are different types of scar formation, which all need a different approach in treatment. Therefore, it is important to differentiate between these types of scar, not only clinically but also histopathologically. Differences were explored for collagen orientation and bundle thickness in 25 normal skin, 57 normotrophic scar, 56 hypertrophic scar, and 56 keloid biopsies, which were selected on clinical diagnosis. Image analysis was performed by fast fourier transformation. The calculated collagen orientation index ranged from 0 (random orientation) to 1 (parallel orientation). The bundle distance was calculated by the average distance between the centers of the collagen bundles. The results showed that compared with all three types of scars, the collagen orientation index was significantly lower in normal skin, which indicates that scars are organized in a more parallel manner. No differences were found between the different scars. Secondly, compared with normal skin, normotrophic scar, and hypertrophic scar, the bundle distance was significantly larger in keloidal scar, which suggests that thicker collagen bundles are present in keloidal scar. This first extensive histological study showed objective differences between normal skin, normotrophic, hypertrophic, and keloidal scar.
The rise and evolution of the cambial variant in Bignonieae (Bignoniaceae)
Authors: Pace Marcelo R. , Lohmann Lúcia G. , Angyalossy Veronica
Published: September 2009

SUMMARYCambial variants represent a form of secondary growth that creates great stem anatomical diversity in lianas. Despite the importance of cambial variants, nothing is known about the developmental mechanisms that may have led to the current diversity seen in these stems. Here, a thorough anatomical analysis of all genera along the phylogeny of Bignonieae (Bignoniaceae) was carried out in order to detect when in their ontogeny and phylogeny there were shifts leading to different stem anatomical patterns. We found that all species depart from a common developmental basis, with a continuous, regularly growing cambium. Initial development is then followed by the modification of four equidistant portions of the cambium that reduce the production of xylem and increase the production of phloem, the former with much larger sieve tubes and an extended lifespan. In most species, the formerly continuous cambium becomes disjunct, with cambial portions within phloem wedges and cambial portions between them. Other anatomical modifications such as the formation of multiples of four phloem wedges, multiple‐dissected phloem wedges, and included phloem wedges take place thereafter. The fact that each novel trait raised on the ontogenetic trajectory appeared in subsequently more recent ancestors on the phylogeny suggests a recapitulatory history. This recapitulation is, however, caused by the terminal addition of evolutionary novelties rather than a truly heterochronic process. Truly heterochronic processes were only found in shrubby species, which resemble juveniles of their ancestors, as a result of a decelerated phloem formation by the variant cambia. In addition, the modular evolution of phloem and xylem in Bignonieae seems to indicate that stem anatomical modifications in this group occurred at the level of cambial initials.
Eyespot evolution: phylogenetic insights from Junonia and related butterfly genera (Nymphalidae: Junoniini)
Authors: Kodandaramaiah Ullasa
Published: September 2009

SUMMARY
Butterfly eyespots have been the focus of a number of developmental and evolutionary studies. However, a phylogenetic component has rarely been explicitly incorporated in these studies. In this study, I utilize a phylogeny to trace the evolution of eyespot number and position on the wing in a group of nymphalid butterflies, the subtribe Junoniini. These butterflies have two kinds of eyespot arrangements which I refer to as Serial and Individual. In the Serial arrangement, eyespots are placed in a series on compartments 1−6 (counting from the anterior wing margin). In the Individual arrangement, eyespots are isolated on specific compartments, ranging from 1 to 4 in number. This can be divided into four subtypes based on the number and positions of eyespots. I map the evolution of these five arrangements over a phylogeny of Junoniini reconstructed with ca. 3000 base pairs of sequence data from three genes. The results show that almost all arrangements have evolved at least twice, with multiple shifts between them by addition and deletion of eyespots. I propose a model involving genetic or developmental coupling between eyespots in specific compartments to explain these shifts. I discuss their evolution in light of existing knowledge about their development. I also discuss potential explanations for functional significance of the eyespot patterns found in the group. Differential selection for and against eyespots, both at different times over the phylogeny and in different regions, have driven the evolution of eyespot arrangements. The study throws open many questions about the adaptive significance of eyespots and the developmental underpinnings of the various arrangements.
Expression ofDazlandVasain turtle embryos and ovaries: evidence for inductive specification of germ cells
Authors: Bachvarova Rosemary F. , Crother Brian I. , Manova Katia , Chatfield Jodie , Shoemaker Christina M. , Crews David P. , Johnson Andrew D.
Published: September 2009

SUMMARYIn bilaterian animals, germ cells are specified by the inductive/regulative mode or the predetermined (germ plasm) mode. Among tetrapods, mammals and urodeles use the inductive mode, whereas birds and anurans use the predetermined mode. From histological data it has been predicted that some reptiles including turtles use the inductive mode. Examining turtle oocytes, we find thatDazlRNA,VasaRNA, and Vasa protein are not localized, suggesting that germ plasm is not present. In turtle embryos at somite stages, primordial germ cells (PGCs) expressingDazllie on a path from the lateral posterior extraembryonic endoderm through the gut to the gonad as previously described. In gastrulating embryos, cells expressingDazlare found in the blastoporal plate and subsequently below the blastoporal plate, indicating that PGCs are generated at the equivalent of the early posterior primitive streak of mammals.VasaRNA is expressed in somatic cells of gastrula to early somite stages, andVasaRNA and protein are expressed in PGCs of later embryos. Taken together the evidence strongly suggests that turtles, and other reptiles (lacertoid lizards) with the same location of PGCs in embryos, use the inductive mode of germ cell specification. Phylogenetic analysis of the available evidence supports the following hypotheses: (1) the inductive mode is basal among reptiles, indicating that this mode was maintained as basal tetrapods evolved to amniotes, (2) the predetermined mode arose twice within reptiles, and (3) the induced mode may be used in several lepidosaurs whose PGCs are located in an unusual pattern distributed around the embryo.
Regulation of expression of zebrafish (Danio rerio) insulin‐like growth factor 2 receptor: implications for evolution at the IGF2R locus
Authors: Tsalavouta Matina , Astudillo Olaya , Byrnes Lucy , Nolan Catherine M.
Published: September 2009

SUMMARY
The insulin‐like growth factor 2 receptor (IGF2R) is an unusual multifunctional receptor that interacts with a diverse variety of ligands. While the receptor has been well‐characterized in mammals, little is known of its biology in other vertebrates. In this report, we characterize the expression of the zebrafish (Danio rerio) ortholog of the IGF2R gene. We show that two distinct, cell‐type‐specific promoters drive transcription of zebrafish igf2r and that these encode receptor isoforms that differ in their amino termini. Both promoters are active in adult fish and during embryonic development, but the proximal promoter generates more abundant transcripts. The 5′‐UTR of the more abundantly expressed transcript contains several AUGs upstream of the main start codon, and these negatively regulate translation of a downstream reporter gene. Comparative sequence analysis shows that upstream AUGs (uAUGs) are a feature of IGF2R genes in several other vertebrates, including Xiphophorus, Xenopus, chicken, platypus, and opossum, but not in eutherian mammals. The IGF2R is imprinted in marsupial and placental mammals, and this transcriptional control of receptor abundance was proposed to have evolved following acquisition of an insulin‐like growth factor 2 (IGF2) binding site by the ancestral receptor. Our observations suggest that receptor abundance was regulated at translation in ancestral vertebrates, before acquisition of an IGF2 binding site. We propose that evolution of imprinting at the mammalian IGF2R may have facilitated the loss of negative regulation of translation conferred by uAUGs.
Evolution of germ cell development in tetrapods: comparison of urodeles and amniotes
Authors: Bachvarova Rosemary F. , Crother Brian I. , Johnson Andrew D.
Published: September 2009

SUMMARY. The embryonic development of germ cells in tetrapods is described, focusing on groups with the inductive mode of germ cell specification. In mammals PGCs are induced early in the gastrulation process, they are internalized with future extraembryonic mesoderm in the early posterior primitive streak, and specified soon thereafter. Strong evidence indicates that a similar process occurs in turtles and some other reptiles. In amniotes, the PGCs appear well before formation of the gonad in the posterior trunk, resulting in a period in which they are located outside the embryo before their migration to the gonad. In contrast, in urodeles the PGCs appear relatively late, and throughout development maintain a position close to precursors of the somatic cells of the gonad so that migration is not required. In lampreys early development of germ cells is strikingly similar to that in urodeles, suggesting this is the primitive process. As amniotes evolved large yolky eggs and better access to nutrition, development of the posterior half of the trunk became more dependent on cell proliferation; this was followed or accompanied by a shift of early germ cell development to the equivalent of the early primitive streak. A similar process may have occurred as some basal vertebrates developed large yolky eggs.
The treatment gap of epilepsy in a rural district of Vietnam: A study from the EPIBAVI project
Authors: Tuan Nguyen Anh , Tomson Torbjörn , Allebeck Peter , Chuc Nguyen Thi Kim , Cuong Le Quang
Published: September 2009

We analyzed the treatment gap by interviewing 189 persons previously identified as having active epilepsy in a population‐based epidemiological project in a rural district of Vietnam (EPIBAVI). Only 29 persons were on regular treatment with antiepileptic drugs (AEDs) at the time of the survey; treatment gap 84.7% [95% confidence interval (CI) 79.5–89.8%). The treatment gap was not associated with age, gender, education, income, or seizure control status, but was higher among those living single compared to those who were married (p < 0.05). The most common reason for not taking AEDs expressed by patients who never tried, as well as among those who tried but discontinued, AEDs was the perception that their seizures were too few to justify the trouble and costs associated with treatment.
Antiepileptic drugs in children in developing countries: Research and treatment guideline needs
Authors: Farkhondeh Mina , Hill Suzanne R. , Cross J. Helen , Dua Tarun
Published: September 2009

Epilepsy is the most common neurologic disorder in childhood. Effective interventions are available for treatment; however, the treatment gap in children is more than 80% in many developing countries. An important reason for this huge treatment gap is limited access to antiepileptic drugs (AEDs). This article discusses the reasons for such a treatment gap, and possible ways forward in improving care of children with epilepsy worldwide.
OOSPORE VARIATION IN CLOSELY RELATED CHARA TAXA1
Authors: Blume Maja , Blindow Irmgard , Dahlke Sven , Vedder Franziska
Published: September 2009

Charophytes produce a thick‐walled zygote, the so‐called oospore, the characters of which (size, shape, and structure) are used as taxonomic determination criteria. In the present study, the variation of length, width, length‐to‐width ratio, and number of striae of oospores collected both from the field and after cross‐fertilization experiments was compared within and among taxa, populations, and individuals belonging to the Chara baltica Bruzelius “species complex.” Although the oospore characteristics differed significantly among the taxa, the variations among populations belonging to the same taxon and even among individuals belonging to the same population were still higher. Oospores developed by means of allogamy were not significantly different from oospores developed by autogamy. Oospores were 5% shorter and 27% narrower when measured dry compared with wet material. Information about this treatment is unfortunately lacking in charophyte monographs and oospore determination keys. We concluded that oospore descriptions of different charophyte taxa should be based on a larger amount of data material collected from different populations and individuals and accompanied by a detailed method description, and that a determination of closely related taxa by means of oospores should be interpreted carefully. Ecological aspects of oospore size variation are discussed.
ANALYSIS OF A PLASTID MULTIGENE DATA SET AND THE PHYLOGENETIC POSITION OF THE MARINE MACROALGA CAULERPA FILIFORMIS (CHLOROPHYTA)1
Authors: Zuccarello G. C. , Price Natalie , Verbruggen Heroen , Leliaert Frederik
Published: September 2009

Molecular phylogenetic relationships within the Chlorophyta have relied heavily on rRNA data. These data have revolutionized our insight in green algal evolution, yet some class relationships have never been well resolved. A commonly used class within the Chlorophyta is the Ulvophyceae, although there is not much support for its monophyly. The relationships among the Ulvophyceae, Trebouxiophyceae, and Chlorophyceae are also contentious. In recent years, chloroplast genome data have shown their utility in resolving relationships between the main green algal clades, but such studies have never included marine macroalgae. We provide partial chloroplast genome data (∼30,000 bp, 23 genes) of the ulvophycean macroalga Caulerpa filiformis (Suhr) K. Herig. We show gene order conservation for some gene combinations and rearrangements in other regions compared to closely related taxa. Our data also revealed a pseudogene (ycf62) in Caulerpa species. Our phylogenetic results, based on analyses of a 23‐gene alignment, suggest that neither Ulvophyceae nor Trebouxiophyceae are monophyletic, with Caulerpa being more closely related to the trebouxiophyte Chlorella than to Oltmannsiellopsis and Pseudendoclonium.
Centrifugal Gradients of Rate and Organization in Human Atrial Fibrillation
Authors: KRUMMEN DAVID E. , PENG KEVIN A. , BULLINGA JOHN R. , NARAYAN SANJIV M.
Published: September 2009

Introduction:

Animal studies show that atrial fibrillation (AF) may emanate from sites of high rate and regularity, with fibrillatory conduction to adjacent areas. We used simultaneous mapping to find evidence for potential drivers in human AF defined as sites with higher rate and regularity than surrounding tissue.

Materials and Methods:

In 24 patients (age 61 ± 10 years; 12 persistent), we recorded AF simultaneously from 32 left atrial bipolar basket electrodes in addition to pulmonary veins (PV), coronary sinus, and right atrial electrodes. We measured AF cycle length (CL) by Fourier transform and electrogram regularity at each electrode, referenced to patient‐specific atrial anatomy.

Results:

We analyzed 10,298 electrode‐periods. Evidence for potential AF drivers was found in 11 patients (five persistent). In persistent AF, these sites lay at the coronary sinus and left atrial roof but not PVs, while in paroxysmal AF six of nine sites lay at PVs (P < 0.05). During ablation, a subset of patients experienced AF CL prolongation or termination with a focal lesion; in each case this lesion mapped to potential driver sites on blinded analysis. Conversely, sequential mapping failed to reveal these sites, possibly due to fluctuations in dominant frequency at driver locations in the context of migratory AF.

Conclusions:

Simultaneous multisite recordings in human AF reveal evidence for drivers that lie near PVs in paroxysmal but not persistent AF, and were sites where ablation slowed or terminated AF in a subset of patients. The future work should determine if real‐time ablation of AF‐maintaining regions defined in this fashion eliminates AF.
Pharmacotherapy of Cardiac Arrhythmias—Basic Science for Clinicians
Authors: SHU JUAN , ZHOU JUN , PATEL CHINMAY , YAN GAN‐XIN
Published: September 2009

Cardiac arrhythmias occur in approximately 5.3% of the population and contribute substantially to morbidity and mortality. Pharmacological therapy still remains the major approach in management of patients with nearly every form of cardiac arrhythmia. Effective and safe management of cardiac arrhythmias with antiarrhythmic drugs requires understanding of basic mechanisms for various cardiac arrhythmias, clinical diagnosis of an arrhythmia and identification of underlying cardiac diseases, pharmacokinetics, and antiarrhythmic properties of each individual antiarrhythmic drug. Most cardiac arrhythmias occur via one of the two mechanisms: abnormal impulse formation and reentry or both. Antiarrhythmic drugs primarily work via influencing cardiac automaticity or triggered activity or by their effects on effective refractoriness of cardiac cells. Proarrhythmic effects of antiarrhythmic drugs are also briefly discussed in this review article.
Magnesium Sensitive, Adenosine Resistant, Repetitive Monomorphic Ventricular Tachycardia
Authors: NEIGER JEFFREY S. , GUPTA AKSHAY , HALLERAN SEAN M. , TROHMAN RICHARD G.
Published: September 2009

Repetitive monomorphic ventricular tachycardia (RMVT) is characterized by episodes of ventricular ectopy and nonsustained VT exacerbated by catecholamines. Because this arrhythmia is frequently adenosine sensitive, its mechanism is believed to be cyclic adenosine monophosphate‐mediated triggered activity due to delayed afterdepolarizations. We present a case of RMVT associated with significant hypomagnesemia (serum level = 1.1 mg/dL), which did not respond to intravenous (IV) adenosine and terminated repeatedly after IV magnesium. Electrophysiologic study demonstrated an origin from the left sinus of Valsalva, which was successfully ablated. The combination of adenosine resistance and magnesium sensitivity may be consistent with an atypical RMVT mechanism related to inhibition of sodium‐potassium adenosine triphosphatase (Na+‐K+ATPase).
Transatrial Lead Implantation Using the 4‐Fr Lumenless Pacing Lead and Delivery System in Young Adults with Congenital Heart Disease
Authors: FISHBERGER STEVEN B. , ROLLINSON NANCY R. , WARSY IRFAN , WANG BRIAN , KIM RICHARD W.
Published: September 2009

We report the technique of transatrial delivery of the Medtronic 3830 SelectSecure lead (Medtronic Inc., Minneapolis, MN, USA) for right ventricular endocardial pacing in two young adults with congenital heart disease who had multiple pacing lead failures and superior vena cava occlusion. The deflectable catheter delivery system used to position the SelectSecure lead provided the opportunity to map the right ventricular endocardial surface and determine the best available pacing site. At midterm follow‐up, both systems are functioning well.
An intron 1 polymorphism in the cholecystokinin‐A receptor gene associated with schizophrenia in males
Authors: Koefoed P. , Hansen T. V. O. , Woldbye D. P. D. , Werge T. , Mors O. , Hansen T. , Jakobsen K. D. , Nordentoft M. , Wang A. , Bolwig T. G. , Rehfeld J. F.
Published: September 2009

Objective:  To identify whether a genetic variation (rs1800857; IVS1‐5T>C) in the neuropeptide cholecystokinin‐A receptor (CCKAR) gene is a risk factor in the pathogenesis of schizophrenia.

Method:  The variation was analysed in a case–control design comprising 508 patients with schizophrenia and 1619 control subjects. A possible functional impact of this variant on CCKAR protein synthesis through alterations in splicing was analysed in an exon‐trapping assay.

Results:  In males only, the risk variant, IVS1‐5C, was associated with a significantly increased risk of schizophrenia. Carrying one risk allele was associated with an increased risk of 1.74 (Odds Ratio, OR) and homozygosity (CC) was associated with an OR of 3.19. The variation had no impact on protein synthesis of CCKAR.

Conclusion:  This is the first report associating the CCKAR gene variant with schizophrenia specifically in men. Our study strengthens the conclusion that a CCKAR dysfunction could be involved in the aetiology of schizophrenia.
Scale dependency and functional response in moose habitat selection
Authors: Herfindal Ivar , Tremblay Jean‐Pierre , Hansen Brage B. , Solberg Erling J. , Heim Morten , Sæther Bernt‐Erik
Published: September 2009

Habitat selection can be influenced by the distribution of the habitat types in the landscape as well as net gain in visiting patches of resources, causing individual variation in habitat selection. Moreover, the hypothesis of functional response in habitat selection predicts that the degree of selection of a resource depends on its relative availability. We used radio‐telemetry data from individual moose on an island off the coast of northern Norway to evaluate whether the selection of habitat types at the landscape scale differed from the choice of habitat types within the home range, and investigated the functional response in habitat selection by relating individual habitat selection to home range characteristics. At the landscape scale, moose selected for habitat types that provided both good forage and cover, with small differences between sex and age groups. At the home range scale, all individuals selected habitat types that were associated with cover and low human impact. Habitat selection was not modified by local moose density, but was related to home range size at both spatial scales. Larger home ranges contained larger proportions of non‐preferred habitat types compared to smaller home ranges. At the home range scale, the selection for a habitat type decreased with its relative availability, indicating a functional response in habitat selection. This suggests that habitat selection is modified by home range size, which influences the availability of habitat types and shapes individual habitat selection patterns. Our results support previous suggestions that analyses of habitat or resource selection should follow a multi‐scale approach. Both the relative availability of habitat types as well as individual variation in home range size should be accounted for in order to disentangle the complex mechanisms that contribute to shape patterns of resource selection in animals.
Roles of Cav channels and AHNAK1 in T cells: the beauty and the beast
Authors: Matza Didi , Flavell Richard A.
Published: September 2009

Summary:  T lymphocytes require Ca2+ entry though the plasma membrane for their activation and function. Recently, several routes for Ca2+ entry through the T‐cell plasma membrane after activation have been described. These include calcium release‐activated channels (CRAC), transient receptor potential (TRP) channels, and inositol‐1,4,5‐trisphosphate receptors (IP3Rs). Herein we review the emergence of a fourth new route for Ca2+ entry, composed of Cav channels (also known as L‐type voltage‐gated calcium channels) and the scaffold protein AHNAK1 (AHNAK/desmoyokin). Both helper (CD4+) and killer (CD8+) T cells express high levels of Cav1 α1 subunits (α1S, α1C, α1D, and α1F) and AHNAK1 after their differentiation and require these molecules for Ca2+ entry during an immune response. In this article, we describe the observations and open questions that ultimately suggest the involvement of multiple consecutive routes for Ca2+ entry into lymphocytes, one of which may be mediated by Cav channels and AHNAK1.
CRAC channels and Ca2+ signaling in mast cells
Authors: Di Capite Joseph , Parekh Anant B.
Published: September 2009

Summary:  Mast cells are integral members of the immune system. Upon activation by a rise in cytoplasmic Ca2+, they release a battery of paracrine signals, chemokines, and cytokines, which help sculpt the subsequent immune response. Ca2+ entry through store‐operated Ca2+ release‐activated Ca2+ (CRAC) channels in the plasma membrane is central for driving most of these responses. The molecular basis of the CRAC channel has been identified, with Orai1 forming the channel pore. Recent work has revealed that a range of mast cell responses are activated by spatially restricted Ca2+ signals just below the plasma membrane. These Ca2+ microdomains can activate cytosolic enzymes, leading to the generation of intracellular messengers as well as proinflammatory molecules like LTC4. In this review, we describe key features of CRAC channels in mast cells, how they generate local Ca2+ signals, and how the cell can decode these restricted signals to generate a raft of responses.
Capacitative calcium entry: from concept to molecules
Authors: Putney James W.
Published: September 2009

Summary: Rapid to moderately rapid changes in intracellular Ca2+concentration, or Ca2+signals, control a variety of critical cellular functions in the immune system. These signals are comprised of Ca2+release from intracellular stores coordinated with Ca2+influx across the plasma membrane. The most common mechanisms by which these two modes of signaling occur is through inositol 1,4,5‐trisphosphate (IP3)‐induced release of Ca2+from the endoplasmic reticulum (ER) and store‐operated Ca2+entry across the plasma membrane. The latter process was postulated over 20 years ago, and in just the past few years, the key molecular players have been discovered: STIM proteins serve as sensors of Ca2+within the ER which communicate with and activate plasma membrane store‐operated channels composed of Orai subunits. The process of store‐operated Ca2+entry provides support for oscillating Ca2+signals from the ER and also provides direct activator Ca2+that signals to a variety of downstream effectors.
Physiological function and molecular basis of STIM1‐mediated calcium entry in immune cells
Authors: Baba Yoshihiro , Kurosaki Tomohiro
Published: September 2009

Summary:  Calcium signals in immune cells regulate a variety of physiological responses such as cell activation, differentiation, gene transcription, and effector functions. Surface receptor stimulation induces an increase in the concentration of cytosolic calcium ions (Ca2+), which are derived mainly from two sources, intracellular endoplasmic reticulum (ER) Ca2+ stores and the extracellular space. The major cascade for Ca2+ entry in immune cells is through store‐operated Ca2+ entry (SOCE) and Ca2+ release‐activated Ca2+ (CRAC) channels. Activation of SOCE is triggered by depletion of intracellular ER Ca2+ stores, but the molecular mechanism was a long‐standing issue. With the recent molecular identification of the ER Ca2+ sensor [stromal interacting molecule‐1 (STIM1)] and a pore‐forming subunit of the CRAC channel (Orai1), our understanding of the SOCE activation pathway has increased dramatically. These advances have now made it possible to shed some light on important questions: what is the physiological significance of SOCE, and what is its molecular basis? This review focuses on the recent progress in the field and the exciting opportunities for understanding how SOCE influences diverse immune functions.
Regulation of T‐cell tolerance by calcium/NFAT signaling
Authors: Baine Ian , Abe Brian T. , Macian Fernando
Published: September 2009

Summary:  Cells that escape negative selection in the thymus must be inactivated or eliminated in the periphery through a series of mechanisms that include the induction of anergy, dominant suppression by regulatory T cells, and peripheral deletion of self‐reactive T cells. Calcium signaling plays a central role in the induction of anergy in T cells, which become functionally inactivated and incapable of proliferating and expressing cytokines following antigen re‐encounter. Suboptimal stimulation of T cells results in the activation of a calcium/calcineurin/nuclear factor of activated T cells‐dependent cell‐intrinsic program of self‐inactivation. The proteins encoded by those genes are required to impose a state of functional unresponsiveness through different mechanisms that include downregulation of T‐cell receptor signaling and inhibition of cytokine transcription.
Uncommon specialization in a mutualism between a temperate herbaceous plant guild and an ant: are Aphaenogaster ants keystone mutualists?
Authors: Ness J. H. , Morin D. F. , Giladi I.
Published: September 2009

Ant‐dispersed herbs (myrmecochores) can account for more than one‐third of the stems in the temperate deciduous forests of eastern North America. Because many ant species have been observed collecting the seeds, this interaction is often described as a generalized mutualism. Here, we combine fieldwork and meta‐analyses to test this assumption. Our meta‐analysis demonstrated that Aphaenogaster ants (predominantly A. rudis) collect approximately 74±26% (mean±SD) of the myrmecochorous seeds in eastern North American forests where any encounters with Aphaenogaster were reported, and approximately 61±37% of the seeds in all the eastern forests where any seed collection has been monitored. This remarkable monopolization of seeds is due to at least two factors: 1) Aphaenogaster are significantly more likely to collect the ant‐adapted seeds they discover than are ten other ant genera found in these forests and 2) the densities of Aphaenogaster and myrmecochorous plants are positively correlated at three nested spatial scales (within 20×20 m patches, among patches within a forest, and among 41 forests in the eastern United States). Although other ants can collect seeds, our analyses demonstrate that A. rudis is the primary seed dispersal vector for most of this rich temperate ant‐dispersed flora. The low levels of plant partner diversity for myrmecochores demonstrated here rivals that of tropical ant‐plants (myrmecophytes) and well exceeds that typically observed in temperate plant–frugivore and plant–pollinator mutualisms and myrmecochory in other biomes.
Community‐wide impacts of herbivore‐induced plant regrowth on arthropods in a multi‐willow species system
Authors: Utsumi Shunsuke , Ohgushi Takayuki
Published: September 2009

It has been widely accepted that herbivory induces morphological, phenological, and chemical changes in a wide variety of terrestrial plants. There is an increasing appreciation that herbivore‐induced plant responses affect the performance and abundance of other arthropods. However, we still have a poor understanding of the effects of induced plant responses on community structures of arthropods. We examined the community‐level effects of willow regrowth in response to damage by larvae of swift moth Endoclita excrescence (Lepidoptera: Hepialidae) on herbivorous and predaceous arthropods on three willow species, Salix gilgiana, S. eriocarpa and S. serissaefolia. The leaves of sprouting lateral shoots induced by moth‐boring had a low C:N ratio. The overall abundance and species richness of herbivorous insects on the lateral shoots were increased on all three willow species. Densities of specialist chewers and sap‐feeders, and leaf miners increased on the newly emerged lateral shoots. In contrast, the densities of generalist chewers and sap‐feeders, and gall makers did not increase. Furthermore, ant and spider densities, and the overall abundance and species richness of predaceous arthropods increased on the lateral shoots on S. gilgiana and S. eriocarpa, but not S. serissaefolia. In addition to finding that effects of moth‐boring on arthropod abundance and species richness varied among willow species, we also found that moth‐boring, willow species, and their interaction differentially affected community composition. Our findings suggest that moth‐boring has community‐wide impacts on arthropod assemblages across three trophic levels via induced shoot regrowth and increase arthropod species diversity in this three willow species system.
The signaling function of an extra‐floral display: what selects for signal development?
Authors: Keasar Tamar , Sadeh Adi , Gerchman Yoram , Shmida Avi
Published: September 2009

The vertical inflorescences of the Mediterranean annualSalvia viridiscarry many small, colorful flowers, and are frequently terminated by a conspicuous tuft of colorful leaves (‘flag’) that attracts insect visitors. Insects may use the flags as indicators of food rewards in the inflorescences below, as long‐distance cues for locating and choosing flowering patches, or both. Clipping of all flags from patches of inflorescences in the field reduced the number of arriving insects, but not the total number of inflorescences and flowers visited by them. The number of flowers visited per inflorescence increased with inflorescence size, and inflorescence and flower visits rates significantly increased with patch size. Six percent of the plants in the study population did not develop any flag during blooming, yet suffered no reduction in seed set as compared to flag‐bearing neighboring individuals. Removal of flags from all inflorescences in a patch reduced seed set in comparison with untreated controls, while flag clipping from ten randomly selected inflorescences in a patch did not decrease seed production. These results suggest that flags signal long‐distance information to potential pollinators (possibly indicating patch location or size), while flower‐related cues may indicate inflorescence quality.

Plants that do not develop flags probably benefit from the flag signals displayed by their neighbors, without bearing the costs of signal production. Greenhouse‐grownS. viridisplants allocated a low proportion of their biomass to flags. Plants grown under water stress did not reduce biomass allocation to flags as compared to irrigated controls. Water loss rates of picked flags were lower than those of picked leaves. These findings suggest that the expenses of flag production and maintenance are modest, reducing the selective advantage of individuals that do not carry flags. We discuss additional potential evolutionary mechanisms that may select for flag production.
New perspectives for estimating body condition from mass/length data: the scaled mass index as an alternative method
Authors: Peig Jordi , Green Andy J.
Published: September 2009

Body condition is assumed to influence an animal's health and fitness. Various non‐destructive methods based on body mass and a measure of body length have been used as condition indices (CIs), but the dominant method amongst ecologists is currently the calculation of residuals from an ordinary least squares (OLS) regression of body mass against length. Recent studies of energy reserves in small mammals and starlings claimed to validate this method, although we argue that they did not include the most appropriate tests since they compared the CI with the absolute size of energy reserves. We present a novel CI (the ‘scaled mass index’) based on the central principle of scaling, with important methodological, biological and conceptual advantages. Through a reanalysis of data from small mammals, starlings and snakes, we show that the scaled mass index is a better indicator of the relative size of energy reserves and other body components than OLS residuals, performing better in all seven species and in 19 out of 20 analyses. We also present an empirical and theoretical comparison of the scaled mass index and OLS residuals as CIs. We argue that the scaled mass index is a useful new tool for ecologists.
Dispersal limitation inferred from an experimental translocation ofLomatium(Apiaceae) species outside their geographic ranges
Authors: Marsico Travis D. , Hellmann Jessica J.
Published: September 2009

Determining limitations on poleward range expansion is important for predicting how climate change will alter the distribution of species. For most species, it is not known what factors set their distributional limits and the role dispersal limitation might play if range‐limiting factors were altered. We conducted a transplant study of three related and co‐occurringLomatiumspecies at their northern range limits to test competing hypotheses of range limitation. We added seeds to experimental plots inside and outside the species’ geographic range (a regional treatment) in a replicated design with vegetation intact and vegetation reduced (a disturbance treatment) and with herbivore access and herbivore exclusion (an herbivory treatment). Germination and reemergence were measured through two growing seasons, along with community‐level variables. A fully‐crossed linear mixed model revealed thatLomatiumsurvivorship outside the current range was as good or better than survivorship within the range, at least when the vegetative community remained intact. This suggests that the species are dispersal limited. Germination often was improved in the presence of an intact vegetative community, but this potentially facilitative effect was absent in second‐year reemergence. Plots exposed to herbivory had slightly, but significantly, reduced germination, though reemergence did not differ between herbivore treatments.Lomatium dissectum, a rare species, had significantly lower survivorship than its congeners, suggesting that range shifts in rare taxa may be particularly difficult. Seed additions beyond species’ range limits may be a strategy for overcoming dispersal limitation and assisting species in poleward migrations.