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61.
MARTIN FIKÁČEK ALEXANDER PROKIN ROBERT B. ANGUS ALEXANDER PONOMARENKO YANLI YUE DONG REN JAKUB PROKOP 《Systematic Entomology》2012,37(3):420-447
We performed a phylogenetic analysis focused on the hydrophiloid family Helophoridae (Coleoptera: Polyphaga) in order to test the phylogenetic position of selected Mesozoic fossils assigned to the Hydrophiloidea. The analysis is based on 92 characters of larvae and adults, and includes all extant subgenera of Helophorus and representatives of all other extant hydrophiloid families. Based on this analysis, we provide additional evidence for the monophyly of the helophorid lineage containing the families Helophoridae, Georissidae and Epimetopidae, as well as the first hypothesis on the phylogenetic relationships within Helophorus, revealing three main clades: Lihelophorus, Rhopalohelophorus and the clade of sculptured small subgenera; the subgenera Helophorus s.str., Gephelophorus, Trichohelophorus and Transithelophorus are recognized as paraphyletic or polyphyletic. Inclusion of fossil species in the analysis reveals the Mesozoic genera Hydrophilopsia Ponomarenko, Laetopsia Fiká?ek et al. (adult forms) and Cretotaenia Ponomarenko (larval form) as basal extinct clades of the helophorid lineage, the former genus Mesosperchus Ponomarenko as containing probable stem taxa of Helophorus and the former genus Mesohelophorus Ponomarenko as a member of the Helophorus clade containing extant sculptured subgenera. The extant subgenus Thaumhelophorus syn.nov. is synonymized with Rhopalohelophorus. Our results show that the family Helophoridae may be dated back to the late Jurassic (c. 150 Ma) and the extant clades of Helophorus back to the Early Cretaceous (c. 136 Ma). The basal groups of Helophorus and the supposed basal extinct lineages of the helophorid lineages are shown to be aquatic as adults. A single origin of trichobothria and ventral hydrophobic pubescence in the common ancestor of the Hydrophiloidea is hypothesized, indicating ancestral aquatic habits in the adult stage for the whole Hydrophiloidea. 相似文献
62.
J. POKORNÁ K. SCHWARZEROVÁ S. ZELENKOVÁ J. PETRÁEK I. JANOTOVÁ V. APKOVÁ & Z. OPATRNÝ 《Plant, cell & environment》2004,27(5):641-653
Cytoskeletal proteins assemble into dynamic polymers that play many roles in nuclear and cell division, signal transduction, and determination of cell shape and polarity. The distribution and dynamics of microtubules (MTs) and actin filaments (AFs) are determined, among other factors, by the location of their nucleation sites. Whereas the sites of microtubule nucleation in plants are known to be located under the plasma membrane and on the nuclear envelope during interphase, there is a striking lack of information about nucleation sites of AFs. In the studies reported herein, low temperature (0 °C) was used to de‐polymerize AFs and MTs in tobacco BY‐2 (Nicotiana tabacum L.) cells at interphase. The extent of de‐polymerization of cytoskeletal filaments in interphase cells during cold treatment and the subcellular distribution of nucleation sites during subsequent recovery at 25 °C were monitored by means of fluorescence microscopy. The results show that AFs re‐polymerized rapidly from sites located in the cortical region and on the nuclear envelope, similarly to the initiation sites of MTs. In contrast to MTs, however, complete reconstitution of AFs was preceded by the formation of transient actin structures including actin dots, rods, and filaments with a dotted signal. Immunoblotting of soluble and sedimentable protein fractions showed no changes in the relative amounts of free and membrane‐bound actin or tubulin. 相似文献
63.
PHYTOALEXIN DEFICIENT 4 affects reactive oxygen species metabolism,cell wall and wood properties in hybrid aspen (Populus tremula L. × tremuloides) 下载免费PDF全文
IRENEUSZ ŚLESAK MAGDALENA SZECHYŃSKA‐HEBDA HALINA FEDAK NATALIA SIDORUK JOANNA DĄBROWSKA‐BRONK DAMIAN WITOŃ ANNA RUSACZONEK ANDRZEJ ANTCZAK MICHAŁ DROŻDŻEK BARBARA KARPIŃSKA STANISŁAW KARPIŃSKI 《Plant, cell & environment》2015,38(7):1275-1284
The PHYTOALEXIN DEFICIENT 4 (PAD4) gene in Arabidopsis thaliana (AtPAD4) is involved in the regulation of plant – pathogen interactions. The role of PAD4 in woody plants is not known; therefore, we characterized its function in hybrid aspen and its role in reactive oxygen species (ROS)‐dependent signalling and wood development. Three independent transgenic lines with different suppression levels of poplar PAD expression were generated. All these lines displayed deregulated ROS metabolism, which was manifested by an increased H2O2 level in the leaves and shoots, and higher activities of manganese superoxide dismutase (MnSOD) and catalase (CAT) in the leaves in comparison to the wild‐type plants. However, no changes in non‐photochemical quenching (NPQ) between the transgenic lines and wild type were observed in the leaves. Moreover, changes in the ROS metabolism in the pad4 transgenic lines positively correlated with wood formation. A higher rate of cell division, decreased tracheid average size and numbers, and increased cell wall thickness were observed. The results presented here suggest that the Populus tremula × tremuloides PAD gene might be involved in the regulation of cellular ROS homeostasis and in the cell division – cell death balance that is associated with wood development. 相似文献
64.
Addona TA Shi X Keshishian H Mani DR Burgess M Gillette MA Clauser KR Shen D Lewis GD Farrell LA Fifer MA Sabatine MS Gerszten RE Carr SA 《Nature biotechnology》2011,29(7):635-643
We developed a pipeline to integrate the proteomic technologies used from the discovery to the verification stages of plasma biomarker identification and applied it to identify early biomarkers of cardiac injury from the blood of patients undergoing a therapeutic, planned myocardial infarction (PMI) for treatment of hypertrophic cardiomyopathy. Sampling of blood directly from patient hearts before, during and after controlled myocardial injury ensured enrichment for candidate biomarkers and allowed patients to serve as their own biological controls. LC-MS/MS analyses detected 121 highly differentially expressed proteins, including previously credentialed markers of cardiovascular disease and >100 novel candidate biomarkers for myocardial infarction (MI). Accurate inclusion mass screening (AIMS) qualified a subset of the candidates based on highly specific, targeted detection in peripheral plasma, including some markers unlikely to have been identified without this step. Analyses of peripheral plasma from controls and patients with PMI or spontaneous MI by quantitative multiple reaction monitoring mass spectrometry or immunoassays suggest that the candidate biomarkers may be specific to MI. This study demonstrates that modern proteomic technologies, when coherently integrated, can yield novel cardiovascular biomarkers meriting further evaluation in large, heterogeneous cohorts. 相似文献
65.
David EK Ferrier 《BMC biology》2011,9(1):3
The phylum to which humans belong, Chordata, takes its name from one of the major shared derived features of the group, the
notochord. All chordates have a notochord, at least during embryogenesis, and there is little doubt about notochord homology
at the morphological level. A study in BMC Evolutionary Biology now shows that there is greater variability in the molecular genetics underlying notochord development than previously appreciated. 相似文献
66.
One of the most exciting and compelling areas of research and development is building brain machine interfaces (BMIs) for controlling prosthetic limbs. Prosthetic limb technology is advancing rapidly, and the modular prosthetic limb (MPL) of the Johns Hopkins University/ Applied Physics Laboratory (JHU/APL) permits actuation with 17 degrees of freedom in 26 articulating joints. There are many signals from the brain that can be leveraged, including the spiking rates of neurons in the cortex, electrocorticographic (ECoG) signals from the surface of the cortex, and electroencephalographic (EEG) signals from the scalp. Unlike microelectrodes that record spikes, ECoG does not penetrate the cortex and has a higher spatial specificity, signal-to-noise ratio, and bandwidth than EEG signals. We have implemented an ECoG-based system for controlling the MPL in the Johns Hopkins Hospital Epilepsy Monitoring Unit, where patients are implanted with ECoG electrode grids for clinical seizure mapping and asked to perform various recorded finger or grasp movements. We have shown that low-frequency local motor potentials (LMPs) and ECoG power in the high gamma frequency (70,150 Hz) range correlate well with grasping parameters, and they stand out as good candidate features for closed-loop control of the MPL. 相似文献
67.
68.
Revisiting Coptotermes (Isoptera: Rhinotermitidae): a global taxonomic road map for species validity and distribution of an economically important subterranean termite genus 下载免费PDF全文
THOMAS CHOUVENC HOU‐FENG LI JAMES AUSTIN CHRISTIAN BORDEREAU THOMAS BOURGUIGNON STEPHEN L. CAMERON ELIANA M. CANCELLO REGINALDO CONSTANTINO ANA MARIA COSTA‐LEONARDO PAUL EGGLETON THEODORE A. EVANS BRIAN FORSCHLER J. KENNETH GRACE CLAUDIA HUSSENEDER JAN KŘEČEK CHOW‐YANG LEE TIMOTHY LEE NATHAN LO MATTHEW MESSENGER AARON MULLINS ALAIN ROBERT YVES ROISIN RUDOLF H. SCHEFFRAHN DAVID SILLAM‐DUSSÈS JAN ŠOBOTNÍK ALLEN SZALANSKI YOKO TAKEMATSU EDWARD L. VARGO AKINORI YAMADA TSUYOSHI YOSHIMURA NAN‐YAO SU 《Systematic Entomology》2016,41(2):299-306
69.
DAVID MODRÝ KLÁRA J. PETRELKOVÁ KATEINA POMAJBÍKOVÁ TOSHIHIRO TOKIWA JAROSLAV KÍEK SOICHI IMAI PETER VALLO ILONA PROFOUSOVÁ JAN LAPETA 《The Journal of eukaryotic microbiology》2009,56(1):83-87
ABSTRACT. Entodiniomorphid ciliates are often present in the colons of wild apes. In captive apes the infection tends to gradually disappear, with the exception of Troglodytella abrassarti . We used fecal examinations to screen the gorillas ( Gorilla gorilla gorilla ) in European (Czech Republic, UK) and Australian Zoos to explore the ape-to-ape transmission pattern of T. abrassarti . Gorillas from two out of three European Zoos were positive for T. abrassarti , while gorillas from the Australian Zoo were negative. We documented a horizontal transmission of T. abrassarti to a non-infected adult gorilla introduced into a Troglodytella -positive group in the Prague Zoo and traced the origin of the ciliate infection to the Paignton Zoo (UK) using serial fecal examinations. During this study, two infant gorillas born in the Prague Zoo (CZ) first became positive for T. abrassarti at the age of 9 mo. Ciliate morphology and the sequencing of the small subunit rRNA gene and the internal transcribed spacer rDNA spacer region revealed that T. abrassarti affects both captive gorillas and chimpanzees. We conclude that zoo transport plays a major role in the distribution of T. abrassarti among captive gorillas. 相似文献