5,179 research outputs found
Isolation and characterization of microsatellite loci from two inbreeding bark beetle species (Coccotrypes)
We developed 14 microsatellite markers in Coccotrypes carpophagus and 14 in C. dactyliperda.
These loci will be used for studying genetic structure and the level of inbreeding in
populations in the Canary Islands and Madeira. As a result of long-term inbreeding,
genetic variability is relatively low in these bark beetle species. We found one to five alleles
per locus in 29 C. carpophagus and 41 C. dactyliperda from various localities. Eleven of the
markers developed for C. carpophagus amplified in C. dactyliperda and seven of the markers
developed for C. dactyliperda amplified in C. carpophagus
Lyopreserved amniotic membrane is cellularly and clinically similar to cryopreserved construct for treating foot ulcers
We compared cellular viability between cryopreserved and lyopreserved amniotic membranes and clinical outcomes of the lyopreserved construct in a prospective cohort study of 40 patients with neuropathic foot ulcers. Patients received weekly application of lyopreserved membrane for 12 weeks with standard weekly debridement and offloading. We evaluated the proportion of foot ulcers that closed, time to closure, closure trajectories, and infection during therapy. We used chi-square tests for dichotomous variables and independent t-tests for continuous variables with an alpha of Ξ± =.10. Cellular viability was equivalent between cryo- and lyopreserved amniotic tissues. Clinically, 48% of subjects' wounds closed in an average of 40.0 days. Those that did not close were older (63 vs 59 years, P =.011) and larger ulcers at baseline (7.8 vs 1.6 cm2, P =.012). Significantly more patients who achieved closure reached a 50% wound area reduction in 4 weeks compared with non-closed wounds (73.7% vs 47.6%, P =.093). There was no difference in the slope of the wound closure trajectories between closed and non-closed wounds (0.124 and 0.159, P =.85), indicating the rate of closure was similar. The rate of closure was 0.60 mm/day (SD = 0.47) for wounds that closed and 0.50 mm/day (SD = 0.58) for wounds that did not close (P =.89)
The Certification of ATLAS Thin Gap Chambers Produced in Israel and China
Thin gap chambers (TGCs) are used for the muon trigger system in the forward
region of the LHC experiment ATLAS. A TGC consists of a plane of closely spaced
wires maintained at positive high voltage, sandwiched between resistive
grounded cathode planes with an anode wire to cathode plane gap distance
smaller than the wire-to-wire spacing. The TGCs are expected to provide a
trigger signal within 25 ns of the bunch spacing of the LHC accelerator, with
an efficiency exceeding 95%, while exposed to an effective photon and neutron
background ranging from 30 to 500 Hz/cm2. About 2,500 out of the 3,600 ATLAS
TGCs are being produced at the Weizmann institute in Israel, and in Shandong
University in China. Once installed in the ATLAS detector the TGCs will be
inaccessible. A vigorous production quality control program is therefore
implemented at the production sites. Furthermore, after chamber completion, a
thorough program of quality assurance is implemented to ensure the efficient
performance of the chambers during more than ten years of operation in the LHC
high rate environment. This program consists of a detailed mapping of the
detectors response using cosmic rays, as well as checking the chambers behavior
using a high rate radiation source. An aging test performed on five chambers in
a serial gas connection is presented. Finally the results of the chambers
certification tests performed at CERN before the installation in ATLAS are
described.Comment: Presented at 2004 IEEE Nuclear Science Symposium 2004, Rome, Oct 200
Bacterial solutions to multicellularity: a tale of biofilms, filaments and fruiting bodies
Microbial Biotechnolog
Resolution of the type material of the Asian elephant, Elephas maximus Linnaeus, 1758 (Proboscidea, Elephantidae)
The understanding of Earthβs biodiversity depends critically on the accurate identification and nomenclature of
species. Many species were described centuries ago, and in a surprising number of cases their nomenclature or type
material remain unclear or inconsistent. A prime example is provided by Elephas maximus, one of the most iconic
and well-known mammalian species, described and named by Linnaeus (1758) and today designating the Asian
elephant. We used morphological, ancient DNA (aDNA), and high-throughput ancient proteomic analyses to
demonstrate that a widely discussed syntype specimen of E. maximus, a complete foetus preserved in ethanol, is
actually an African elephant, genus Loxodonta. We further discovered that an additional E. maximus syntype,
mentioned in a description by John Ray (1693) cited by Linnaeus, has been preserved as an almost complete skeleton
at the Natural History Museum of the University of Florence. Having confirmed its identity as an Asian elephant
through both morphological and ancient DNA analyses, we designate this specimen as the lectotype of E. maximus
Pseudomonas aeruginosa Adaptation to Lungs of Cystic Fibrosis Patients Leads to Lowered Resistance to Phage and Protist Enemies
Pathogenic life styles can lead to highly specialized interactions with host species, potentially resulting in fitness trade-offs in other ecological contexts. Here we studied how adaptation of the environmentally transmitted bacterial pathogen, Pseudomonas aeruginosa, to cystic fibrosis (CF) patients affects its survival in the presence of natural phage (14/1, Ξ¦KZ, PNM and PT7) and protist (Tetrahymena thermophila and Acanthamoebae polyphaga) enemies. We found that most of the bacteria isolated from relatively recently intermittently colonised patients (1-25 months), were innately phage-resistant and highly toxic for protists. In contrast, bacteria isolated from long time chronically infected patients (2-23 years), were less efficient in both resisting phages and killing protists. Moreover, chronic isolates showed reduced killing of wax moth larvae (Galleria mellonella) probably due to weaker in vitro growth and protease expression. These results suggest that P. aeruginosa long-term adaptation to CF-lungs could trade off with its survival in aquatic environmental reservoirs in the presence of microbial enemies, while lowered virulence could reduce pathogen opportunities to infect insect vectors; factors that are both likely to result in poorer environmental transmission. From an applied perspective, phage therapy could be useful against chronic P. aeruginosa lung infections that are often characterized by multidrug resistance: chronic isolates were least resistant to phages and their poor growth will likely slow down the emergence of beneficial resistance mutations
Interaction of eukaryotic translation initiation factor 4G with the nuclear cap-binding complex provides a link between nuclear and cytoplasmic functions of the m7 guanosine cap
In eukaryotes the majority of mRNAs have an m7G cap that is added cotranscriptionally and that plays an important role in many aspects of mRNA metabolism. The nuclear cap-binding complex (CBC; consisting of CBP20 and CBP80) mediates the stimulatory functions of the cap in pre-mRNA splicing, 3' end formation, and U snRNA export. As little is known about how nuclear CBC mediates the effects of the cap in higher eukaryotes, we have characterized proteins that interact with CBC in HeLa cell nuclear extracts as potential mediators of its function. Using cross-linking and coimmunoprecipitation, we show that eukaryotic translation initiation factor 4G (eIF4G), in addition to its function in the cytoplasm, is a nuclear CBC-interacting protein. We demonstrate that eIF4G interacts with CBC in vitro and that, in addition to its cytoplasmic localization, there is a significant nuclear pool of eIF4G in mammalian cells in vivo. Immunoprecipitation experiments suggest that, in contrast to the cytoplasmic pool, much of the nuclear eIF4G is not associated with eIF4E (translation cap binding protein of eIF4F) but is associated with CBC. While eIF4G stably associates with spliceosomes in vitro and shows close association with spliceosomal snRNPs and splicing factors in vivo, depletion studies show that it does not participate directly in the splicing reaction. Taken together the data indicate that nuclear eIF4G may be recruited to pre-mRNAs via its interaction with CBC and accompanies the mRNA to the cytoplasm, facilitating the switching of CBC for eIF4F. This may provide a mechanism to couple nuclear and cytoplasmic functions of the mRNA cap structure
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