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81.
Yannick Willemen Johan M. J. Van den Bergh Eva Lion Sébastien Anguille Vicky A. E. Roelandts Heleen H. Van Acker Steven D. I. Heynderickx Barbara M. H. Stein Marc Peeters Carl G. Figdor Viggo F. I. Van Tendeloo I. Jolanda de Vries Gosse J. Adema Zwi N. Berneman Evelien L. J. Smits 《Cancer immunology, immunotherapy : CII》2015,64(7):831-842
82.
Andréa E A Stephens Anne M Barrington Vicky A Bush Nadine M Fletcher Vanessa J Mitchell D Max Suckling 《Australian Journal of Entomology》2008,47(2):131-136
Abstract Two methods of marking painted apple moth ( Teia anartoides Walker, Lepidoptera: Lymantriidae), internal and external dyes, were investigated for use with the sterile insect technique, to ensure that wild and released moths could be distinguished absolutely during the eradication program. Calco Red dye was used to mark all moths internally. It was added to artificial diet and was detectable in the adults. Dye was incorporated into the larval diet at four rates. No differences were observed in mortality of the larvae, fertility of the adult female or response of male moths to virgin females in a flight tunnel. Fluorescent powder dyes were used throughout the sterile insect program to identify irradiated moths, as well as their release location and colony. However, the powdered dyes reduced the ability of male moths to detect a component of the sex pheromone in electro-antennogram tests and to respond to a calling virgin female in flight tunnel trials. Field trials suggest that moths may subsequently overcome these negative effects and respond to female moths, as moths heavily coated in dye were recaptured. 相似文献
83.
Herrel A Schaerlaeken V Ross C Meyers J Nishikawa K Abdala V Manzano A Aerts P 《Integrative and comparative biology》2008,48(2):261-271
Electromyography (EMG), or the study of muscle activation patterns,has long been used to infer central nervous system (CNS) controlof the musculoskeletal system and the evolution of that control.As the activation of the muscles at the level of the peripheryis a reflection of the interaction of descending influencesand local reflex control, EMG is an important tool in integratedinvestigations of the evolution of coordination in complex,musculoskeletal systems. Yet, the use of EMG as a tool to understandthe evolution of motor control has its limitations. We herereview the potential limitations and opportunities of the useof EMG in studying the evolution of motor control in vertebratesand provide original previously unpublished data to illustratethis. The relative timing of activation of a set of musclescan be used to evaluate CNS coordination of the components ina musculoskeletal system. Studies of relative timing revealtask-dependent variability in the recruitment of different populationsof muscle fibers (i.e., different fiber types) within a singlemuscle, and left–right asymmetries in activation thatneed to be taken into account in comparative studies. The magnitudeof muscle recruitment is strongly influenced by the instantaneousdemands imposed on the system, and is likely determined by localreflex-control systems. Consequently, using EMG to make meaningfulinferences about evolutionary changes in musculoskeletal controlrequires comparisons across similar functional tasks. Moreover,our data show that inferences about the evolution of motor controlare limited in their explanatory power without proper insightsinto the kinematics and dynamics of a system. 相似文献
84.
Karen A. Stockin Vicky Binedell † Nicky Wiseman ‡ Dianne H. Brunton § Mark B. Orams # 《Marine Mammal Science》2009,25(2):283-301
Here we present the first data describing the behavior of common dolphins ( Delphinus sp.) in the Hauraki Gulf, New Zealand. Activity budgets are used to assess the effects of diel, season, depth, sea surface temperature, group size, and composition on dolphin behavior. Additionally, the presence/absence of Bryde's whale ( Balaenoptera brydei ) and Australasian gannet ( Morus serrator ) is examined in relation to dolphin behavior. Behavioral data were collected from 686 independent dolphin groups during boat-based surveys conducted between February 2002 and January 2005. Foraging (46.7%) and social (7.2%) were the most and least frequently observed behaviors, respectively. Travel (28.9%), mill (9.5%), and rest (7.7%) accounted for the remainder of the activity budget. Behavior varied seasonally, with the highest proportion of foraging and resting groups observed during the spring and autumn, respectively. Behavior also varied with water depth, with foraging animals observed in the deepest and resting groups recorded in the shallowest regions of the Hauraki Gulf. A correlation between group size and behavior was evident, although behavior did not vary with the composition of dolphin groups. Resting, milling, and socializing animals were more frequently observed in smaller group sizes. Foraging behavior was prevalent in both small and large group sizes, suggesting foraging plasticity exists within this population. Behavior differed between single- and multispecies groups, with foraging more frequent in multispecies groups. Resting, milling, or socializing was rarely observed in the presence of any associated species, indicating the primary mechanism for association is likely prey related. 相似文献
85.
Acehan D Vaz F Houtkooper RH James J Moore V Tokunaga C Kulik W Wansapura J Toth MJ Strauss A Khuchua Z 《The Journal of biological chemistry》2011,286(2):899-908
Barth syndrome is an X-linked genetic disorder caused by mutations in the tafazzin (taz) gene and characterized by dilated cardiomyopathy, exercise intolerance, chronic fatigue, delayed growth, and neutropenia. Tafazzin is a mitochondrial transacylase required for cardiolipin remodeling. Although tafazzin function has been studied in non-mammalian model organisms, mammalian genetic loss of function approaches have not been used. We examined the consequences of tafazzin knockdown on sarcomeric mitochondria and cardiac function in mice. Tafazzin knockdown resulted in a dramatic decrease of tetralinoleoyl cardiolipin in cardiac and skeletal muscles and accumulation of monolysocardiolipins and cardiolipin molecular species with aberrant acyl groups. Electron microscopy revealed pathological changes in mitochondria, myofibrils, and mitochondrion-associated membranes in skeletal and cardiac muscles. Echocardiography and magnetic resonance imaging revealed severe cardiac abnormalities, including left ventricular dilation, left ventricular mass reduction, and depression of fractional shortening and ejection fraction in tafazzin-deficient mice. Tafazzin knockdown mice provide the first mammalian model system for Barth syndrome in which the pathophysiological relationships between altered content of mitochondrial phospholipids, ultrastructural abnormalities, myocardial and mitochondrial dysfunction, and clinical outcome can be completely investigated. 相似文献
86.
Tanya Majumder Min Liu Vicky Chen Marife Martinez Danielle Alvarado Karl V. Clemons David A. Stevens 《Mycopathologia》2014,178(3-4):189-195
Heat-killed Saccharomyces cerevisiae (HKY) vaccination protects mice against aspergillosis, coccidioidomycosis, mucormycosis, or candidiasis. We studied HKY protection against murine cryptococcosis. Once weekly subcutaneous HKY doses (S, 6 × 107; 2S, 1.2 × 108; 3S, 2.4 × 108) began 28 (×3), 35 (×4), or 42 (×6) days prior to intravenous Cryptococcus grubii infection. Survival through 28 days, and CFU in the organs of survivors, were compared to saline-vaccinated controls. In the initial experiment, S, S×4, or 2S reduced brain CFU; liver or spleen CFU was reduced by S×4 or 2S. In a more lethal second experiment, 2S×6, 2S, or 3S×4 improved survival, and HKY regimens reduced CFU in the brain, liver, or spleen, with 2S×6, 2S, or 3S×4 most efficacious. Dose size appears more important than the number of doses: Regimens >S were superior, and 2S and 2S×6 were equivalent. 2S and 3S were equivalent, suggesting doses >2S do not provide additional protection. HKY protects against Cryptococcus, supporting components of HKY as a basis for the development of a panfungal vaccine. 相似文献
87.
Vicky Dritsou Elena Deligianni Emmanuel Dialynas James Allen Nikos Poulakakis Christos Louis Dan Lawson Pantelis Topalis 《BMC genomics》2014,15(1)
Background
Only a small fraction of the mosquito species of the genus Anopheles are able to transmit malaria, one of the biggest killer diseases of poverty, which is mostly prevalent in the tropics. This diversity has genetic, yet unknown, causes. In a further attempt to contribute to the elucidation of these variances, the international “Anopheles Genomes Cluster Consortium” project (a.k.a. “16 Anopheles genomes project”) was established, aiming at a comprehensive genomic analysis of several anopheline species, most of which are malaria vectors. In the frame of the international consortium carrying out this project our team studied the genes encoding families of non-coding RNAs (ncRNAs), concentrating on four classes: microRNA (miRNA), ribosomal RNA (rRNA), small nuclear RNA (snRNA), and in particular small nucleolar RNA (snoRNA) and, finally, transfer RNA (tRNA).Results
Our analysis was carried out using, exclusively, computational approaches, and evaluating both the primary NGS reads as well as the respective genome assemblies produced by the consortium and stored in VectorBase; moreover, the results of RNAseq surveys in cases in which these were available and meaningful were also accessed in order to obtain supplementary data, as were “pre-genomic era” sequence data stored in nucleic acid databases. The investigation included the identification and analysis, in most species studied, of ncRNA genes belonging to several families, as well as the analysis of the evolutionary relations of some of those genes in cross-comparisons to other members of the genus Anopheles.Conclusions
Our study led to the identification of members of these gene families in the majority of twenty different anopheline taxa. A set of tools for the study of the evolution and molecular biology of important disease vectors has, thus, been obtained.Electronic supplementary material
The online version of this article (doi:10.1186/1471-2164-15-1038) contains supplementary material, which is available to authorized users. 相似文献88.
Ding Y Girardet JL Smith KL Larson G Prigaro B Lai VC Zhong W Wu JZ 《Bioorganic & medicinal chemistry letters》2005,15(3):675-678
From compound library screening using an HCV NS5B RNA-dependent RNA polymerase enzymatic assay, we identified a pteridine hit compound with an IC(50) of 15 microM. Our SAR studies were focused on the different groups at the 6- and 7-positions, substitutions at the 4-position, and replacement of N(1) or N(3) with carbon in the pteridine ring. We found that NH or OH at 4-position is critical for the inhibitory activity. Furthermore, a hydrophobic substituent at the 4-position may help compounds permeate through the cell membrane. 相似文献
89.
Sabrina H. van Ierssel Emeline M. Van Craenenbroeck Vicky Y. Hoymans Christiaan J. Vrints Viviane M. Conraads Philippe G. Jorens 《PloS one》2013,8(8)
Background
Outcome in sepsis is mainly defined by the degree of organ failure, for which endothelial dysfunction at the macro- and microvascular level is an important determinant. In this study we evaluated endothelial function in patients with severe sepsis using cellular endothelial markers and in vivo assessment of reactive hyperaemia.Materials and Methods
Patients with severe sepsis (n = 30) and 15 age- and gender- matched healthy volunteers were included in this study. Using flow cytometry, CD34+/KDR+ endothelial progenitor cells (EPC), CD31+ T-cells, and CD31+/CD42b- endothelial microparticles (EMP) were enumerated. Migratory capacity of cultured circulating angiogenic cells (CAC) was assessed in vitro. Endothelial function was determined using peripheral arterial tonometry at the fingertip.Results
In patients with severe sepsis, a lower number of EPC, CD31+ T-cells and a decreased migratory capacity of CAC coincided with a blunted reactive hyperaemia response compared to healthy subjects. The number of EMP, on the other hand, did not differ. The presence of organ failure at admission (SOFA score) was inversely related with the number of CD31+ T-cells. Furthermore, the number of EPC at admission was decreased in patients with progressive organ failure within the first week.Conclusion
In patients with severe sepsis, in vivo measured endothelial dysfunction coincides with lower numbers and reduced function of circulating cells implicated in endothelial repair. Our results suggest that cellular markers of endothelial repair might be valuable in the assessment and evolution of organ dysfunction. 相似文献90.