bluuebunny/crossref_metadata_2025_split huggingface dataset:
Phylogenetic relationships and biogeography of midwife toads (Discoglossidae: Alytes)
Authors: Martínez‐Solano I. , Gonçalves H. A. , Arntzen J. W. , García‐París M. 
Published: October 2010

AbstractAim  To devise a robust phylogenetic hypothesis for midwife toads (Alytes: Anura: Discoglossidae) and to discuss its implications for the reconstruction of the biogeographical history of the group.Location  Western Palearctic.Methods  Analysis of sequences of mitochondrial DNA (cytochrome b and 16S RNA, 861 bp) and 29 characters of cranial osteology of all species and subspecies within Alytes.Results  Phylogenetic analyses support a sister group relationship between Alytes dickhilleni and A. muletensis, and of this clade with A. maurus. The monophyly of A. obstetricans is controversial; in particular, the phylogenetic position of A. obstetricans almogavarii is uncertain. The estimated dates for the cladogenetic events within Alytes are congruent with those derived from independent analyses (allozymes), except for the differentiation of A. o. almogavarii and the split between A. dickhilleni and A. muletensis.Main conclusions  The phylogeny based on the analysis of morphological and mtDNA data differs from previous hypotheses in the positions of A. o. almogavarii and A. maurus. Events associated with the radiation of Alytes are the formation of large inland saline lakes in Iberia c. 16 Ma and the 11 ° C dramatic decrease in average annual temperature during the Middle–Late Badenian transition c. 14–13.5 Ma (A.cisternasii vs. the ancestor of the remaining clades), the structuring of the Neo‐Pyrenees and the reopening of the Betic Strait c. 10–8 Ma(A. o. almogavarii vs. A. obstetricans and vs. the subgenus Baleaphryne), the opening of the Gibraltar Strait at the end of the Messinian Salinity Crisis at c. 5.3 Ma (A. maurus vs. the ancestor of the A. dickhilleni A. muletensis clade) and a transmarine colonization event at c. 3 Ma (the ancestor of A. muletensis vs. A. dickhilleni). Following the new hypothesis, A. maurus, previously considered a subspecies of A. obstetricans, deserves species status. Second, A. o. almogavarii is a well‐differentiated lineage that was isolated from other A. obstetricans more than c. 5 Ma, but later lost its genetic and specific identity following secondary contact, hybridization and introgression with the main stock. The presence of a marked morphological and genetic diversity within A. obstetricans renders reconstruction of the evolutionary history of the genus more complicated than previously appreciated.
Island biogeography and the species richness of introduced mammals on New Zealand offshore islands
Authors: Russell J. C. , Clout M. N. , McArdle B. H. 
Published: October 2010

AbstractAim  To investigate and establish the significance of various island biogeographic relationships (geographical, ecological and anthropological) with the species richness of introduced mammals on offshore islands.Location  The 297 offshore islands of the New Zealand archipelago (latitude: 34–47°S; longitude: 166–179°E).Methods  Data on New Zealand offshore islands and the introduced mammals on them were collated from published surveys and maps. The species richness of small and large introduced mammals were calculated for islands with complete censuses and regressed on island characteristics using a Poisson distributed error generalized linear model. To estimate the ‘z‐value’ for introduced mammals on New Zealand islands, least‐squares regression was used [log10 S vs. log10 A].Results  High collinearity was found between the area, habitat diversity and elevation of islands. The island characteristics related to the species richness of introduced mammals differed predictably between large and small mammals. The species richness of introduced large mammals was mostly related to human activities on islands, whereas species richness of introduced small mammals was mostly related to island biogeographical parameters. The ‘z‐value’ for total species richness is found to be expectedly low for introduced mammals.Main conclusions  Distance appears to have become ecologically trivial as a filter for introduced mammal presence on New Zealand offshore islands. There is strong evidence of a ‘small island’ effect on New Zealand offshore islands. The species richness of both small and large introduced mammals on these islands appears to be most predominantly related to human use, although there is some evidence of natural dispersal for smaller species. The ecological complexity of some islands appears to make them less invasible to introduced mammals. Some human activities have an interactive effect on species richness. A small number of islands have outlying species richness values above what the models predict, suggesting that the presence of some species may be related to events not accounted for in the models.
Factors controlling the spatial species richness pattern of four groups of terrestrial vertebrates in an area between two different biogeographic regions in northern Spain
Authors: Nogués‐Bravo David , Martínez‐Rica Juan Pablo 
Published: October 2010

AbstractAim  To examine the influence of environmental variables on species richness patterns of amphibians, reptiles, mammals and birds and to assess the general usefulness of regional atlases of fauna.Location  Navarra (10,421 km2) is located in the north of the Iberian Peninsula, in a territory shared by Mediterranean and Eurosiberian biogeographic regions. Important ecological patterns, climate, topography and land‐cover vary significantly from north to south.Methods  Maps of vertebrate distribution and climatological and environmental data bases were used in a geographic information systems framework. Generalized additive models and partial regression analysis were used as statistical tools to differentiate (A) the purely spatial fraction, (B) the spatially structured environmental fraction and (C) the purely environmental fraction. In this way, we can evaluate the explanatory capacity of each variable, avoiding false correlations and assessing true causality. Final models were obtained through a stepwise procedure.Results  Energy‐related features of climate, aridity and land‐cover variables show significant correlation with the species richness of reptiles, mammals and birds. Mammals and birds exhibit a spatial pattern correlated with variables such as aridity index and vegetation land‐cover. However, the high values of the spatially structured environmental fraction B and the low values of the purely environmental fraction A suggest that these predictor variables have a limited causal relationship with species richness for these vertebrate groups. An increment in land‐cover diversity is correlated with an increment of specific richness in reptiles, mammals and birds. No variables were found to be statistically correlated with amphibian species richness.Main conclusions  Although aridity and land‐cover are the best predictor variables, their causal relationship with species richness must be considered with caution. Historical factors exhibiting a similar spatial pattern may be considered equally important in explaining the patterns of species richness. Also, land‐cover diversity appears as an important factor for maintaining biological diversity. Partial regression analysis has proved a useful technique in dealing with spatial autocorrelation. These results highlight the usefulness of coarsely sampled data and cartography at regional scales to predict and explain species richness patterns for mammals and birds. The accuracy of models appears to be related to the range perception of each group and the scale of the information.
Expression of bone morphogenetic proteins and cartilage‐derived morphogenetic proteins during osteophyte formation in humans
Authors: Zoricic Sanja , Maric Ivana , Bobinac Dragica , Vukicevic Slobodan 
Published: October 2010

AbstractBone‐ and cartilage‐derived morphogenetic proteins (BMPs and CDMPs), which are TGFβ superfamily members, are growth and differentiation factors that have been recently isolated, cloned and biologically characterized. They are important regulators of key events in the processes of bone formation during embryogenesis, postnatal growth, remodelling and regeneration of the skeleton. In the present study, we used immunohistochemical methods to investigate the distribution of BMP‐2, ‐3, ‐5, ‐6, ‐7 and CDMP‐1, ‐2, ‐3 in human osteophytes (abnormal bony outgrowths) isolated from osteoarthritic hip and knee joints from patients undergoing total joint replacement surgery. All osteophytes consisted of three different areas of active bone formation: (1) endochondral bone formation within cartilage residues; (2) intramembranous bone formation within the fibrous tissue cover and (3) bone formation within bone marrow spaces. The immunohistochemistry of certain BMPs and CDMPs in each of these three different bone formation sites was determined. The results indicate that each BMP has a distinct pattern of distribution. Immunoreactivity for BMP‐2 was observed in fibrous tissue matrix as well as in osteoblasts; BMP‐3 was mainly present in osteoblasts; BMP‐6 was restricted to young osteocytes and bone matrix; BMP‐7 was observed in hypertrophic chondrocytes, osteoblasts and young osteocytes of both endochondral and intramembranous bone formation sites. CDMP‐1, ‐2 and ‐3 were strongly expressed in all cartilage cells. Surprisingly, BMP‐3 and ‐6 were found in osteoclasts at the sites of bone resorption. Since a similar distribution pattern of bone morphogenetic proteins was observed during embryonal bone development, it is suggested that osteophyte formation is regulated by the same molecular mechanism as normal bone during embryogenesis.
Concordia discors: duality in the origin of the vertebrate tail
Authors: Handrigan Gregory R. 
Published: October 2010

AbstractThe vertebrate tail is an extension of the main body axis caudal to the anus. The developmental origin of this structure has been a source of debate amongst embryologists for the past century. Some view tail development as a continuation of the morphogenetic processes that shape the head and trunk (i.e. gastrulation). The alternative view, secondary development, holds that the tail forms in a manner similar to limb development, i.e. by secondary induction. Previous developmental studies have provided support for both views. Here I revisit these studies, describing caudal morphogenesis in select vertebrates, the associated genes and developmental defects, and, as a relevant aside, consider the developmental and evolutionary relationships of primary and secondary neurulation. I conclude that caudal development enlists both gastrulation and secondary induction, and that the application of recent high‐resolution cell labelling technology may clarify how these discordant programmes interact in building the vertebrate tail.
Histological and immunohistological investigation of the lymphoid tissue in normal and mycobacteria‐affected specimens of the Rufous Hare‐wallaby (Lagorchestes hirsutus)
Authors: Young L. J. , McFarlane R. , Slender A. L. , Deane E. M. 
Published: October 2010

AbstractThe histology of the spleen, lymph nodes, Gut‐associated lymphoid tissue (GALT) and Bronchus‐associated lymphoid tissue (BALT) are described for samples collected opportunistically from healthy and mycobacteria‐affected specimens of the endangered marsupialLagorchestes hirsutus, the Rufous Hare‐wallaby. The structural elements, organization and distribution of T and B lymphocytes determined by immunohistological techniques using species cross‐reactive antibodies in the lymph nodes, spleen and GALT of this species demonstrated lymphoid cell distributions that were consistent with other marsupial and eutherian mammals. The tissues of animals identified as acid‐fast positive displayed immunopathology consistent with the responses to intracellular bacteria displayed in some eutherian mammals and included the presence of focal lesions, giant cells in the lung and lymphoid aggregations situated adjacent to blood and airway vessels. This is the first study to describe the lymphoid tissue of this rare macropod species and the first to document the tissue bed response to mycobacteria.
The equine hind limb is actively stabilized during standing
Authors: Schuurman Simon O. , Kersten Wim , Weijs Wim A. 
Published: October 2010

AbstractHorses spend much of their life standing, and they are believed to be able to keep their limbs straight without muscular effort. We tested the hypothesis that the stifle (knee) and hock (tarsal) joints could be stabilized merely with the help of a passive lock mechanism whereby the patella is secured behind a hook, formed by the medial femoral trochlea. In anaesthetized animals and isolated limbs the stifle and hock flex readily under compression. In isolated limbs this collapse was prevented by a small force applied to the patella, mimicking the action of the vastus medialis muscle. In vivo, when the limb was planted loosely on the ground none of the muscles with a connection to the patella was active. However, during weight‐bearing the vastus medialis (but no other muscle) was active, providing the necessary traction to stabilize the stifle. The required tension was estimated to be less than 2% of the force that would be needed in absence of a lock mechanism. Diagnosis and treatment of patellar fixation should include the possibility of overactive vastus medialis muscle as a possible cause of the disorder.
Immunocytochemical characteristics of elbow, knee and ankle muscles of the five‐toed jerboa (Allactaga elater)
Authors: Jouffroy F. K. , Medina M. F. , Renous S. , Gasc J.‐P. 
Published: October 2010

AbstractBiochemical adaptations of limb myofibres to intensive bipedal hopping were investigated using the five‐toed jerboa Allactaga elater as a model in comparison with the rat. Immunofluorescence methods included immunoreactivity to anti‐fast and anti‐slow MHC and troponin I. There is no specialization of triceps caput mediale for postural function in the minute non‐locomotor forelimbs, unlike quadruped mammals. The various elbow extensor heads and the flexor muscles are alike with regard to fibre type population and cross‐sectional areas of each type of fibre. The extensor muscle in the elongated hindlimbs of the five‐toed jerboa, at both the knee and the ankle joints, differ from each other extensively. One head, made up of an extremely high percentage of type I, fatigue‐resistant fibres, is suited to postural function. Two extensor heads at each joint contain a very high percentage of type IIB fibres (having the greatest maximal velocity of contraction) and are able to produce the powerful acceleration needed to trigger the leap. The relative cross‐sectional areas of the myofibres are characteristic of hopping locomotion: predominance in number of one type of myofibre in a muscle accompanies greater cross‐sectional area, which increases muscle efficiency in either postural or accelerative function of the muscle.
Early GABAA receptor clustering during the development of the rostral nucleus of the solitary tract
Authors: Heck W. L. , Basaraba A. M. , Slusarczyk A. , Schweitzer L. 
Published: October 2010

AbstractWhile there is an abundance of gamma‐aminobutyric acid (GABA) in the gustatory zone of the nucleus of the solitary tract of the perinatal rat, we know that GABAergic synapse formation is not complete until well after birth. Our recent results have shown that GABAB receptors are present at birth in the cells of the nucleus; however, they do not redistribute and cluster at synaptic sites until after PND10. The present study examined the time course of appearance and redistribution of GABAA receptors in the nucleus. GABAA receptors were also present at birth. However, in comparison to GABAB receptors, GABAA receptors underwent an earlier translocation to synaptic sites. Extrasynaptic label, for example, of GABAA receptors was non‐existent compared to GABAB receptors at PND10 and well‐defined clusters of GABAA receptors could be seen as early as PND1. We propose that while GABAA receptors may play an early neurotransmitter role at the synapse, GABAB receptors may play a non‐transmitter neurotrophic role.
Radiography of soft tissue of the foot and ankle with diffraction enhanced imaging
Authors: Li Jun , Zhong Zhong , Lidtke Roy , Kuettner Klaus E. , Peterfy Charles , Aliyeva Elmira , Muehleman Carol 
Published: October 2010

AbstractNon‐calcified tissues, including tendons, ligaments, adipose tissue and cartilage, are not visible, for any practical purposes, with conventional X‐ray imaging. Therefore, any pathological changes in these tissues generally necessitate detection through magnetic resonance imaging or ultrasound technology. Until recently the development of an X‐ray imaging technique that could detect both bone and soft tissues seemed unrealistic. However, the introduction of diffraction enhanced X‐ray imaging (DEI) which is capable of rendering images with absorption, refraction and scatter rejection qualities has allowed detection of specific soft tissues based on small differences in tissue densities. Here we show for the first time that DEI allows high contrast imaging of soft tissues, including ligaments, tendons and adipose tissue, of the human foot and ankle.
Intralaryngeal neuroanatomy of the recurrent laryngeal nerve of the rabbit
Authors: Ryan Stephen , McNicholas Walter T. , O'Regan Ronan G. , Nolan Philip 
Published: October 2010

AbstractWe undertook this study to determine the detailed neuroanatomy of the terminal branches of the recurrent laryngeal nerve (RLN) in the rabbit to facilitate future neurophysiological recordings from identified branches of this nerve. The whole larynx was isolated post mortem in 17 adult New Zealand White rabbits and prepared using a modified Sihler's technique, which stains axons and renders other tissues transparent so that nerve branches can be seen in whole mount preparations. Of the 34 hemi‐laryngeal preparations processed, 28 stained well and these were dissected and used to characterize the neuroanatomy of the RLN. In most cases (23/28) the posterior cricoarytenoid muscle (PCA) was supplied by a single branch arising from the RLN, though in five PCA specimens there were two or three separate branches to the PCA. The interarytenoid muscle (IA) was supplied by two parallel filaments arising from the main trunk of the RLN rostral to the branch(es) to the PCA. The lateral cricoarytenoid muscle (LCA) commonly received innervation from two fine twigs branching from the RLN main trunk and travelling laterally towards the LCA. The remaining fibres of the RLN innervated the thyroarytenoid muscle (TA) and comprised two distinct branches, one supplying the pars vocalis and the other branching extensively to supply the remainder of the TA. No communicating anastomosis between the RLN and superior laryngeal nerve within the larynx was found. Our results suggest it is feasible to make electrophysiological recordings from identified terminal branches of the RLN supplying laryngeal adductor muscles separate from the branch or branches to the PCA. However, the very small size of the motor nerves to the IA and LCA suggests that it would be very difficult to record selectively from the nerve supply to individual laryngeal adductor muscles.
Immunohistochemistry of the canine vomeronasal organ
Authors: Dennis J. C. , Allgier J. G. , Desouza L. S. , Eward W. C. , Morrison E. E. 
Published: October 2010

AbstractThe canine's olfactory acuity is legendary, but neither its main olfactory system nor its vomeronasal system has been described in much detail. We used immunohistochemistry on paraffin‐embedded sections of male and female adult dog vomeronasal organ (VNO) to characterize the expression of proteins known to be expressed in the VNO of several other mammals. Basal cell bodies were more apparent in each section than in rodent VNO and expressed immunoreactivity to anticytokeratin and antiepidermal growth factor receptor antibodies. The thin layer of neurone cell bodies in the sensory epithelium and axon fascicles in the lamina propria expressed immunoreactivity to neurone cell adhesion molecule, neurone‐specific beta tubulin and protein gene product 9.5. Some neurones expressed growth‐associated protein 43 (GAP43): and a number of those also expressed neurone‐specific beta tubulin‐immunoreactivity. Some axon fascicles were double labelled for those two proteins. The G‐protein alpha subunits Gi and Go, involved in the signal transduction pathway, showed immunoreactivity in the sensory cell layer. Our results demonstrate that the canine vomeronasal organ contains a population of cells that expresses several neuronal markers. Furthermore, GAP43 immunoreactivity suggests that the sensory epithelium is neurogenic in adult dogs.
Regional US carbon sinks from three-dimensional atmospheric CO
2
sampling
Authors: Crevoisier Cyril , Sweeney Colm , Gloor Manuel , Sarmiento Jorge L. , Tans Pieter P. 
Published: October 2010

Studies diverge substantially on the actual magnitude of the North American carbon budget. This is due to the lack of appropriate data and also stems from the difficulty to properly model all the details of the flux distribution and transport inside the region of interest. To sidestep these difficulties, we use here a simple budgeting approach to estimate land-atmosphere fluxes across North America by balancing the inflow and outflow of CO
2
from the troposphere. We base our study on the unique sampling strategy of atmospheric CO
2
vertical profiles over North America from the National Oceanic and Atmospheric Administration/Earth System Research Laboratory aircraft network, from which we infer the three-dimensional CO
2
distribution over the continent. We find a moderate sink of 0.5 ± 0.4 PgC y
-1
for the period 2004–2006 for the coterminous United States, in good agreement with the forest-inventory-based estimate of the first North American State of the Carbon Cycle Report, and averaged climate conditions. We find that the highest uptake occurs in the Midwest and in the Southeast. This partitioning agrees with independent estimates of crop uptake in the Midwest, which proves to be a significant part of the US atmospheric sink, and of secondary forest regrowth in the Southeast. Provided that vertical profile measurements are continued, our study offers an independent means to link regional carbon uptake to climate drivers.
Large-scale in vivo femtosecond laser neurosurgery screen reveals small-molecule enhancer of regeneration
Authors: Samara Chrysanthi , Rohde Christopher B. , Gilleland Cody L. , Norton Stephanie , Haggarty Stephen J. , Yanik Mehmet Fatih 
Published: October 2010

Discovery of molecular mechanisms and chemical compounds that enhance neuronal regeneration can lead to development of therapeutics to combat nervous system injuries and neurodegenerative diseases. By combining high-throughput microfluidics and femtosecond laser microsurgery, we demonstrate for the first time large-scale in vivo screens for identification of compounds that affect neurite regeneration. We performed thousands of microsurgeries at single-axon precision in the nematodeCaenorhabditis elegansat a rate of 20 seconds per animal. Following surgeries, we exposed the animals to a hand-curated library of approximately one hundred small molecules and identified chemicals that significantly alter neurite regeneration. In particular, we found that the PKC kinase inhibitor staurosporine strongly modulates regeneration in a concentration- and neuronal type-specific manner. Two structurally unrelated PKC inhibitors produce similar effects. We further show that regeneration is significantly enhanced by the PKC activator prostratin.