bluuebunny/crossref_metadata_2025_split huggingface dataset:
Intra‐ and intermuscular variation in human quadriceps femoris architecture assessed in vivo
Authors: Blazevich Anthony J. , Gill Nicholas D. , Zhou Shi 
Published: August 2006

AbstractDespite the functional importance of the human quadriceps femoris in movements such as running, jumping, lifting and climbing, and the known effects of muscle architecture on muscle function, no research has fully described the complex architecture of this muscle group. We used ultrasound imaging techniques to measure muscle thickness, fascicle angle and fascicle length at multiple regions of the four quadriceps muscles in vivo in 31 recreationally active, but non‐strength‐trained adult men and women. Our analyses revealed a reasonable similarity in the superficial quadriceps muscles, which is suggestive of functional similarity (at least during the uni‐joint knee extension task) given that they act via a common tendon. The deep vastus intermedius (VI) is architecturally dissimilar and therefore probably serves a different function(s). Architecture varies significantly along the length of the superficial muscles, which has implications for the accuracy of models that assume a constant intramuscular architecture. It might also have consequences for the efficiency of intra‐ and intermuscular force transmission. Our results provide some evidence that subjects with a given architecture of one superficial muscle, relative to the rest of the subject sample, also have a similar architecture in other superficial muscles. However, this is not necessarily true for vastus lateralis (VL), and was not the case for VI. Therefore, the relative architecture of one muscle cannot confidently be used to estimate the relative architecture of another. To confirm this, we calculated a value of whole quadriceps architecture by four different methods. Regardless of the method used, we found that the absolute or relative architecture of one muscle could not be used as an indicator of whole quadriceps architecture, although vastus medialis, possibly in concert with VL and the anterior portion of VI, could be used to provide a useful snapshot. Importantly, our estimates of whole quadriceps architecture show a gender difference in whole quadriceps muscle thickness, and that muscle thickness is positively correlated with fascicle angle whereas fascicle length is negatively, although weakly, correlated with fascicle angle. These results are supportive of the validity of estimates of whole quadriceps architecture. These data are interpreted with respect to their implications for neural control strategies, region‐specific adaptations in muscle size in response to training, and gender‐dependent differences in the response to exercise training.
Morphological changes of isolated rat pancreatic islets: a structural, ultrastructural and morphometric study
Authors: Morini Sergio , Braun Mark , Onori Paolo , Cicalese Luca , Elias George , Gaudio Eugenio , Rastellini Cristiana 
Published: August 2006

AbstractImproved techniques for pancreatic islet extraction can yield a reasonable number of transplantable cells. However, the isolation and purification process may damage the islets and impair their physiological functions. The aim of this study was to determine the effect of the isolation procedure on the structure of isolated islets and to correlate this with their functionality. Islets were isolated from rat pancreata and purified by Eurocollins‐Ficoll discontinuous density gradient processing, and then processed for light microscopy, and scanning and transmission electron microscopy. Morphometric analysis was also performed. Islet functionality was determined by reversal of streptozotocin‐induced diabetes and the intraperitoneal glucose tolerance test in a syngeneic rat model of pancreatic islet transplantation. Fragments of variable size and shape comprised a relatively large proportion (26%) of the isolated endocrine tissue. Isolated islets showed slight alterations of cell ultrastructure. Major damage (including breakage of the plasma membrane) and loss of cells were observed in the peripheral cells of the isolated islets. An equal mass of islet equivalent (IEq, islets with an average diameter of 150 µm), but with a different islet equivalent/islet number ratio, was transplanted in diabetic animals. When larger and more complete islets were transplanted (higher ratio), better function of the graft was observed by reversal of hyperglycaemia and response to the glucose tolerance test as compared with the functionality and response of smaller (fragmented) islets transplanted (lower ratio). Digestion, trauma and hypoxia during isolation are responsible for qualitative and quantitative changes of isolated islets. Alterations in normal secretory function after the transplant were related to lower islet equivalent/islet number ratio. The incomplete integrity of the islets may explain the failure of the fine glycaemic metabolic regulation.
Biological tooth replacement
Authors: Sartaj Rachel , Sharpe Paul 
Published: August 2006

AbstractTeeth develop from a series of reciprocal interactions that take place between epithelium and mesenchyme during development of the mouth that begin early in mammalian embryogenesis. The molecular control of key processes in tooth development such as initiation, morphogenesis and cytodifferentiation are being increasingly better understood, to the point where this information can be used as the basis for approaches to produce biological replacement teeth (BioTeeth). This review outlines the current approaches, ideas and progress towards the production of BioTeeth that could form an alternative method for replacing lost or damaged teeth.
Bioengineered nerve regeneration and muscle reinnervation
Authors: Kingham Paul J. , Terenghi Giorgio 
Published: August 2006

AbstractThe peripheral nervous system has the intrinsic capacity to regenerate but the reinnervation of muscles is often suboptimal and results in limited recovery of function. Injuries to nerves that innervate complex organs such as the larynx are particularly difficult to treat. The many functions of the larynx have evolved through the intricate neural regulation of highly specialized laryngeal muscles. In this review, we examine the responses of nerves and muscles to injury, focusing on changes in the expression of neurotrophic factors, and highlight differences between the skeletal limb and laryngeal muscle systems. We also describe how artificial nerve conduits have become a useful tool for delivery of neurotrophic factors as therapeutic agents to promote peripheral nerve repair and might eventually be useful in the treatment of laryngeal nerve injury.
Gene‐linked shift in ganglioside distribution influences growth and vascularity in a mouse astrocytoma
Authors: Abate Laura E. , Mukherjee Purna , Seyfried Thomas N. 
Published: August 2006

AbstractBrain tumor growth and progression is dependent upon vascularity, and is associated with altered ganglioside composition and distribution. In this study, we examined the influence of gangliosides on growth and vascularity in a malignant mouse astrocytoma, CT‐2A. Ganglioside distribution was altered in CT‐2A tumor cells using an antisense construct to β‐1,4‐N‐acetylgalactosaminyltransferase (GalNAc‐T), a key enzyme that uses the simple ganglioside GM3 as a substrate for the synthesis of the more complex gangliosides, GM2, GM1 and GD1a. GalNAc‐T gene expression was significantly lower in CT‐2A cells stably transfected with the antisense GalNAc‐T plasmid, pcDNA3.1/TNG (CT‐2A/TNG) than in either non‐transfected CT‐2A or mock‐transfected (CT‐2A/V) control tumor cells. GM3 was elevated from 16% to 58% of the total ganglioside distribution, whereas GM1 and GD1a were reduced from 17% and 49% to 10% and 17%, respectively, in CT‐2A/TNG tumor cells. Growth, vascularity (blood vessel density and Matrigel assay) and vascular endothelial growth factor (VEGF) expression was significantly less in CT‐2A/TNG tumors than in control CT‐2A brain tumors. In addition, the expression of VEGF, hypoxia‐inducible factor 1α (HIF‐1α) and neuropilin‐1 (NP‐1) was significantly lower in CT‐2A/TNG tumor cells than in control CT‐2A tumor cells. These data suggest that gene‐linked changes in ganglioside composition influence the growth and angiogenic properties of the CT‐2A astrocytoma.
Cyclin‐dependent kinase 5 influences Rohon‐Beard neuron survival in zebrafish
Authors: Kanungo Jyotshnabala , Li Bing‐Sheng , Zheng Yali , Pant Harish C. 
Published: August 2006

AbstractCyclin‐dependent kinase 5 (cdk5), a member of the cyclin‐dependent kinase family, is expressed predominantly in post‐mitotic cell populations. Unlike the other cdks, cdk5 is abundant and most active in differentiated neurons. Here, we describe the function of a cdk5 ortholog in zebrafish. Cdk5 catalytic activity is meager but present in early stages of development. However, at 24 h post‐fertilization (hpf), the activity is remarkably higher and continues to be high through 48 and 72 hpf. Knocking down cdk5 by micro‐injection of a specific siRNA resulted in decreased cdk5 protein level accompanied by reduced kinase activity. In the cdk5 siRNA‐injected embryos, the number of primary sensory Rohon‐Beard (RB) neurons was significantly reduced and there were more apoptotic cells in the brain. These phenotypes were rescued by co‐injection of cdk5 mRNA. Within the first two days of development, RB neurons undergo apoptosis in zebrafish. To examine whether cdk5 has a role in RB neuron survival, cdk5 mRNA was injected into the one‐ to two‐cell embryos. In these embryos, RB neuron apoptosis was inhibited compared with the uninjected control embryos. These results suggest that in zebrafish, cdk5 influences RB neuron survival and potentially regulates early neuronal development.
The activation loop phosphorylation of protein kinase D is an early marker of neuronal DNA damage
Authors: Besirli Cagri G. , Johnson Eugene M. 
Published: August 2006

AbstractIn neurons, DNA damage induces protein synthesis‐dependent apoptosis mediated by the mitochondrial intrinsic cell‐death pathway. Signal transduction cascades activated by genotoxic stress upstream of the mitochondria are largely unknown. We identified protein kinase D (PKD) as one of the earliest markers of neuronal DNA damage. Phosphorylation of the PKD‐activation domain could be detected within 15 min of genotoxic stress and was concurrent with ataxia telangiectasia‐mutated (ATM) activation. PKD stimulation was selective to DNA damage and did not occur with other stress stimuli examined. In vivo, both young and adult rats showed increased levels of phosphorylated PKD in neuronal tissues after injection of DNA‐toxin etoposide. These results indicate that PKD activation is an early neuronal response to DNA damage, suggesting that signaling downstream of PKD may be critical for neuronal survival after genotoxic stress.
The WT1 Wilms' tumor suppressor gene is a downstream target for insulin‐like growth factor‐I (IGF‐I) action in PC12 cells
Authors: Sarfstein Rive , Werner Haim 
Published: August 2006

AbstractThe biological actions of the insulin‐like growth factors, IGF‐I and IGF‐II, are mediated by the ligand‐induced activation of the IGF‐I receptor (IGF‐IR), a transmembrane heterotetramer linked to the ras–raf–mitogen‐activated protein kinase (MAPK) and phosphatidyl inositol 3 kinase (PI3K)–protein kinase B (PKB)/Akt signal transduction cascades. The Wilms' tumor suppressor gene (wt1) encodes a zinc finger transcription factor, WT1, which has been implicated in various cellular processes including proliferation, differentiation and apoptosis. In the present study we demonstrated that IGF‐I modulates the WT1 gene expression in neurally derived PC12 cells in a dose‐ and time‐dependent manner. This effect was mediated through both the MAPK and PI3‐kinase signaling pathways, as shown by the ability of the specific inhibitors UO126 and LY294002 to abrogate IGF‐I action. Moreover, using RT‐PCR and transient transfection assays, we demonstrated that the IGF‐I effect was associated with corresponding changes in WT1 mRNA levels and WT1 promoter activity. In addition, the results of the present study revealed that high WT1 levels were associated with the induction of apoptosis, whereas low WT1 levels were correlated with the inhibition of apoptosis, as demonstrated by poly ADP ribose polymerase (PARP) cleavage, Bax expression, Annexin V‐FITC staining, and by the use of antisense oligonucleotides against WT1. In summary, our results show that the wt1 gene is a novel target for IGF‐I action in neurally derived cells.
Stimulation of excitatory amino acid release from adult mouse brain glia subcellular particles by high mobility group box 1 protein
Authors: Pedrazzi Marco , Raiteri Luca , Bonanno Giambattista , Patrone Mauro , Ledda Sabina , Passalacqua Mario , Milanese Marco , Melloni Edon , Raiteri Maurizio , Pontremoli Sandro , Sparatore Bianca 
Published: August 2006

AbstractThe multifunctional protein high mobility group box 1 (HMGB1) is expressed in hippocampus and cerebellum of adult mouse brain. Our aim was to determine whether HMGB1 affects glutamatergic transmission by monitoring neurotransmitter release from glial (gliosomes) and neuronal (synaptosomes) re‐sealed subcellular particles isolated from cerebellum and hippocampus. HMGB1 induced release of the glutamate analogue [3H]d‐aspartate form gliosomes in a concentration‐dependent manner, whereas nerve terminals were insensitive to the protein. The HMGB1‐evoked release of [3H]d‐aspartate was independent of modifications of cytosolic Ca2+ , but it was blocked by dl‐threo‐β‐benzyloxyaspartate (dl‐TBOA), an inhibitor of glutamate transporters. HMGB1 also stimulated the release of endogenous glutamate in a Ca2+‐independent and dl‐TBOA‐sensitive manner. These findings suggest the involvement of carrier‐mediated release. Moreover, dihydrokainic acid, a selective inhibitor of glutamate transporter 1 (GLT1), does not block the effect of HMGB1, indicating a role for the glial glutamate‐aspartate transporter (GLAST) subtype in this response. We also demonstrate that HMGB1/glial particles association is promoted by Ca2+. Furthermore, although HMGB1 can physically interact with GLAST and the receptor for advanced glycation end products (RAGE), only its binding with RAGE is promoted by Ca2+. These results suggest that the HMGB1 cytokine could act as a modulator of glutamate homeostasis in adult mammal brain.
Isolation and characterization of microsatellite loci in Santalum insulare, Santalaceae
Authors: EMELINE LHUILLIER , ALEXANDRE VAILLANT , JEAN‐FRANÇOIS BUTAUD , JEAN‐MARC BOUVET 
Published: August 2006

AbstractThe forest tree Santalum insulare is endemic to the archipelagos of eastern Polynesia and is threatened by important anthropic pressures. In order to investigate the genetic diversity and structure of this species, we developed eight pairs of primers for nuclear microsatellites. One hundred and sixty‐two individuals distributed in 10 islands were analysed. These loci were all polymorphic and displayed three to 15 alleles per locus. Significant Hardy–Weinberg deviation was detected and interpreted as a result of Wahlund effect. These markers constitute an efficient tool in investigating the genetic patterns of S. insulare populations.
Development of six microsatellite loci for black mangrove (Avicennia germinans)
Authors: CERÓN‐SOUZA IVANIA , RIVERA‐OCASIO ELSIE , FUNK STEPHAN M. , MCMILLAN W. OWEN 
Published: August 2006

AbstractWe developed six new microsatellite loci for the black mangrove (Avicennia germinans), an important member of wetland communities worldwide. Loci showed moderate to high polymorphism and a survey of four locations [Puerto Rico (Jobos Bay and Luquillo), Mexico, French Guyana] revealed clear regional (and local) population structure. All populations were genetically distinct and the two continental populations showed much higher diversity than the two insular Puerto Rican locations. These loci complement those recently published by Nettel et al. (2005) and promise to be valuable for characterizing local and regional population dynamics in the black mangrove.
Development of microsatellite markers in the toxic dinoflagellate Alexandrium minutum (Dinophyceae)
Authors: NAGAI S. , MCCAULEY L. , YASUDA N. , ERDNER D. L. , KULIS D. M. , MATSUYAMA Y. , ITAKURA S. , ANDERSON D. M. 
Published: August 2006

AbstractOutbreaks of paralytic shellfish poisoning caused by the toxic dinoflagellate Alexandrium minutum (Dinophyceae) are a worldwide concern from both the economic and human health points of view. For population genetic studies of A. minutum distribution and dispersal, highly polymorphic genetic markers are of great value. We isolated 12 polymorphic microsatellites from this cosmopolitan, toxic dinoflagellate species. These loci provide one class of highly variable genetic markers, as the number of alleles ranged from four to 12, and the estimate of gene diversity was from 0.560 to 0.862 across the 12 microsatellites; these loci have the potential to reveal genetic structure and gene flow among A. minutum populations.
New microsatellite resources for groupers (Serranidae)
Authors: RAMÍREZ MANUEL ALEJANDRO , PATRICIA‐ACEVEDO JENNY , PLANAS SILVIA , CARLIN JOEL L. , FUNK STEPHAN M. , MCMILLAN W. OWEN 
Published: August 2006

AbstractWe characterized nine microsatellite loci and identified an additional 60 genomic regions containing microsatellites in the red hind grouper, Epinephelus guttatus. The nine loci were highly polymorphic, and primers designed from red hind genomic DNA produced a strong amplification product in a test panel of 16 other groupers in the genera Epinephelus and Mycteroperca collected from across the world. Most of the amplified regions were homologous to the red hind locus and a well‐defined microsatellite repeat was generally evident. The nine loci, together with the 60 uncharacterized microsatellite‐containing regions, provide a powerful tool for ecological and evolutionary studies in groupers.
Development and characterization of microsatellite markers for the endangered northern riffleshell mussel Epioblasma torulosa rangiana (Bivalvia: Unionidae)
Authors: ZANATTA DAVID T. , MURPHY ROBERT W. 
Published: August 2006

AbstractPrimers for six polymorphic microsatellite loci were developed for the endangered northern riffleshell Epioblasma torulosa rangiana from the Sydenham River, Ontario, Canada. These loci along with an additional nine microsatellite loci, developed from other unionoid species, available in the literature, were tested and characterized on individuals from two populations in the Allegheny River; one population in French Creek, PA, USA, and one population from the Sydenham River. Allelic diversity ranged from two to 28 alleles per locus and averaged 13.7 per locus. These primers are being used in a rangewide study on the conservation genetics of remaining extant populations of the northern riffleshell.
Isolation of polymorphic tetranucleotide microsatellite markers for the green‐eyed tree frog (Litoria genimaculata)
Authors: GRAY MELISSA M. , HOSKIN CONRAD J. , BARDELEBEN CAROLYNE 
Published: August 2006

AbstractWe have isolated 16 polymorphic microsatellite markers for the green‐eyed tree frog, Litoria genimaculata, from genomic libraries enriched for (AAGG)n and (AAAG)n repetitive elements. The number of alleles ranges from four to 14 per locus with the observed heterozygosity ranging from 0.36 to 1.00. These markers will be useful for analysis of questions concerning population genetic structure and speciation.
POWSIM: a computer program for assessing statistical power when testing for genetic differentiation
Authors: RYMAN NILS , PALM STEFAN 
Published: August 2006

AbstractKnowledge of statistical power is essential for sampling design and data evaluation when testing for genetic differentiation. Yet, such information is typically missing in studies of conservation and evolutionary genetics, most likely because of complex interactions between the many factors that affect power. powsim is a 32‐bit Windows/DOS simulation‐based computer program that estimates power (and α error) for chi‐square and Fisher's exact tests when evaluating the hypothesis of genetic homogeneity. Optional combinations include the number of samples, sample sizes, number of loci and alleles, allele frequencies, and degree of differentiation (quantified as FST). powsim is available at http://www.zoologi.su.se/~ryman.
Isolation of microsatellite markers in the tiger mosquito Aedes albopictus (Skuse)
Authors: PORRETTA D. , GARGANI M. , BELLINI R. , CALVITTI M. , URBANELLI S. 
Published: August 2006

AbstractAmong the numerous molecular markers available in population genetics, microsatellites are one of the most powerful tools developed in recent years. This paper describes the isolation of six polymorphic microsatellite loci in the tiger mosquito Aedes albopictus using an enriched genomic library technique. Such loci should be an efficient tool in population genetic studies for this mosquito species.
Isolation of polymorphic tetranucleotide microsatellite markers for the ornate nursery frog Cophixalus ornatus
Authors: BARDELEBEN CAROLYNE , GRAY MELISSA M. , HOSKIN CONRAD J. 
Published: August 2006

AbstractWe have isolated 18 polymorphic microsatellite loci for Cophixalus ornatus from genomic libraries enriched for (AAAG)n, (AACC)n and (AAGG)n repetitive elements. The number of alleles ranges from five to 22 per locus with the observed heterozygosity ranging from 0.10 to 0.92. These markers will be useful for the analysis of population structure in C. ornatus and testing alternative models of speciation.
Development and localization of microsatellite markers for the sibling species Chironomus riparius and Chironomus piger (Diptera: Chironomidae)
Authors: NOWAK CARSTEN , HANKELN THOMAS , SCHMIDT ERWIN R. , SCHWENK KLAUS 
Published: August 2006

AbstractFive variable microsatellite loci are reported for the nonbiting midge species Chironomus riparius and Chironomus piger. All loci show considerable intraspecific variation and species‐specific alleles, which allow to discriminate among the two closely related species and their interspecific hybrids, and to estimate genetic diversity within and between populations. Additionally, the loci were localized on C. riparius polytene chromosomes to verify their single copy status and investigate possible chromosomal linkage. The described markers are used in different studies with regard to population and ecological genetics and evolutionary ecotoxicology of Chironomus.