1,633 research outputs found
Role of magnetic resonance imaging in managing selected women with newly diagnosed breast cancer
The purpose of this study is evaluation of therapeutic impact of magnetic resonance imaging (MRI) in breast cancer patients that cannot be imaged adequately with traditional radiology: dense breasts, microcalcifications suspicious for carcinoma in situ or discordance between mammography and ultrasound. A review was performed of 493 patients' records: determination of breast MRI effect on clinical management was made for the selected 70 cases by analysing pre-MRI and post-MRI therapeutic plans. Analysis of final pathology was useful to determine if the change in surgical plan prompted by MRI was appropriate. Breast MRI added clinical information in 52.9% of patients that resulted in 44.3% of management changes that were judged as appropriate in 83.9% of cases. Breast MRI provides additional useful information, but causes more extensive surgery (40%) with no proven prognostic benefit. MRI should be considered optional in the clinical staging of breast cancer and performed in selected cases
Deformation history of the blueschist-facies sequences from the Villa de Cura unit (Northern Venezuela)
The Serrania del Interior terrane is located in Northern Venezuela, that represents the southern margin of the Caribbean plate. This terrane includes the Villa de Cura unit, which mainly consists of multiple sub-units of metamorphosed and deformed Cretaceous volcano-sedimentary sequences. These sequences are commonly interpreted as generated in a supra-subduction zone setting. The structural history of the Villa de Cura blueschists-facies units includes four main deformational phases, from D1 to D4. The first D1 phase is mainly represented by a relict S1 schistosity developed under HP/LT conditions. The relic S1 schistosity is deformed by isoclinal to subisoclinal F2 folds showing similar geometry. The F2 folds are characterized by a continuous S2 crenulation cleavage developed under greenschist-facies metamorphism. The parallelism between the A2 axes and the related L2 mineral lineations suggests an interpretation of the F2 folds as sheath folds developed during non-coaxial deformation. The kinematic indicators suggest a top-to-W sense of shear for the D2 phase. The D3 phase is distinguished by asymmetric, parallel F3 folds with a S vergence. Finally, the D4 phase consists of F4 open, gentle folds with high-angle to sub-vertical axial planes. The collected data suggest a complex deformation history, characterized by coupling of strike-slip tectonics and shortening during the retrograde evolution of the blueschist-facies sequences
Emerging Direct Targeting β-Catenin Agents
Aberrant accumulation of β-catenin in the cell nucleus as a result of deregulation of the Wnt/β-catenin pathway is found in various types of cancer. Direct β-catenin targeting agents are being researched despite obstacles; however, specific β-catenin drugs for clinical treatments have not been approved so far. We focused on direct β-catenin targeting of potential therapeutic value as anticancer agents. This review provides recent advances on small molecule β-catenin agents. Structure-activity relationships and biological activities of reported inhibitors are discussed. This work provides useful knowledge in the discovery of β-catenin agents
Colony size predicts division of labour in Attine ants
Division of labour is central to the ecological success of eusocial insects, yet the evolutionary factors driving increases in complexity in division of labour are little known. The size–complexity hypothesis proposes that, as larger colonies evolve, both non-reproductive and reproductive division of labour become more complex as workers and queens act to maximize inclusive fitness. Using a statistically robust phylogenetic comparative analysis of social and environmental traits of species within the ant tribe Attini, we show that colony size is positively related to both non-reproductive (worker size variation) and reproductive (queen–worker dimorphism) division of labour. The results also suggested that colony size acts on non-reproductive and reproductive division of labour in different ways. Environmental factors, including measures of variation in temperature and precipitation, had no significant effects on any division of labour measure or colony size. Overall, these results support the size–complexity hypothesis for the evolution of social complexity and division of labour in eusocial insects. Determining the evolutionary drivers of colony size may help contribute to our understanding of the evolution of social complexity
Colony size predicts division of labour in Attine ants
Division of labour is central to the ecological success of eusocial insects, yet the evolutionary factors driving increases in complexity in division of labour are little known. The size–complexity hypothesis proposes that, as larger colonies evolve, both non-reproductive and reproductive division of labour become more complex as workers and queens act to maximize inclusive fitness. Using a statistically robust phylogenetic comparative analysis of social and environmental traits of species within the ant tribe Attini, we show that colony size is positively related to both non-reproductive (worker size variation) and reproductive (queen–worker dimorphism) division of labour. The results also suggested that colony size acts on non-reproductive and reproductive division of labour in different ways. Environmental factors, including measures of variation in temperature and precipitation, had no significant effects on any division of labour measure or colony size. Overall, these results support the size–complexity hypothesis for the evolution of social complexity and division of labour in eusocial insects. Determining the evolutionary drivers of colony size may help contribute to our understanding of the evolution of social complexity
Overview of the design of the ITER heating neutral beam injectors
The heating neutral beam injectors (HNBs) of ITER are designed to deliver 16.7MWof 1 MeVD0 or
0.87 MeVH0 to the ITER plasma for up to 3600 s. They will be the most powerful neutral beam\uf0a0(NB)
injectors ever, delivering higher energy NBs to the plasma in a tokamak for longer than any previous
systems have done. The design of the HNBs is based on the acceleration and neutralisation of negative
ions as the efficiency of conversion of accelerated positive ions is so low at the required energy that a
realistic design is not possible, whereas the neutralisation ofH 12 andD 12 remains acceptable ( 4856%).
The design of a long pulse negative ion based injector is inherently more complicated than that of
short pulse positive ion based injectors because:
\u2022 negative ions are harder to create so that they can be extracted and accelerated from the ion source;
\u2022 electrons can be co-extracted from the ion source along with the negative ions, and their
acceleration must be minimised to maintain an acceptable overall accelerator efficiency;
\u2022 negative ions are easily lost by collisions with the background gas in the accelerator;
\u2022 electrons created in the extractor and accelerator can impinge on the extraction and acceleration
grids, leading to high power loads on the grids;
\u2022 positive ions are created in the accelerator by ionisation of the background gas by the accelerated
negative ions and the positive ions are back-accelerated into the ion source creating a massive power
load to the ion source;
\u2022 electrons that are co-accelerated with the negative ions can exit the accelerator and deposit power on
various downstream beamline components.
The design of the ITER HNBs is further complicated because ITER is a nuclear installation which
will generate very large fluxes of neutrons and gamma rays. Consequently all the injector components
have to survive in that harsh environment. Additionally the beamline components and theNBcell,
where the beams are housed, will be activated and all maintenance will have to be performed remotely.
This paper describes the design of theHNBinjectors, but not the associated power supplies, cooling
system, cryogenic system etc, or the high voltage bushingwhich separates the vacuum of the beamline
fromthehighpressureSF6 of the high voltage (1MV) transmission line, through which the power, gas and
coolingwater are supplied to the beam source. Also themagnetic field reduction system is not described
Canine circovirus and Canine adenovirus type 1 and 2 in dogs with parvoviral enteritis
Canine parvovirus type 2 (CPV-2) is one of the most relevant pathogens associated with enteritis in dogs and is frequently
reported in association with the detection of other pathogens in faeces. In this study the concomitant presence of Canine
circovirus (CanineCV) and Canine adenovirus (CAdV) DNA in faecal or intestine samples of 95 dogs with parvovirus
enteritis sampled in Italy (1995–2017) was investigated and the viruses identified were genetically characterised. Potential
correlations with the antigenic variant of CPV-2 and with signalment data and outcome were evaluated. Twenty-eight of 95
(29.5%) CPV-2 infected dogs tested positive to other viruses: 7/28 were also positive to CanineCV, 1/28 to CAdV-1, 18/28
to CAdV-2, 1/28 to CanineCV and CAdV-2, and 1/28 to CAdV-1 and CAdV-2. The frequency of CAdV DNA detection and
coinfections was significantly higher in purebred dogs compared to mixed breed ones (P = 0.002 and 0.009, respectively). The
presence of coinfection was not associated with any other relevant data available, including CPV-2 variant and final outcome.
The detection of CanineCV in a dog sampled in 2009 allowed to backdating its circulation in dogs. The eight CanineCV
completely sequenced were phylogenetically related to the CanineCV identified in dogs, wolves and a badger from Europe,
USA, Argentina and China. Nine CAdV were partially sequenced and phylogenetic analysis showed a separate branch for
the oldest CAdV-2 identified (1995). From the results obtained in this study population, CanineCV and CAdV coinfections
in dogs with parvoviral enteritis did not result in more severe disease
Isolation and Expansion of Muscle Precursor Cells from Human Skeletal Muscle Biopsies
One of the major issues concerning human skeletal muscle progenitor cells is represented by the efficient isolation and in vitro expansion of cells retaining the ability to proliferate, migrate and differentiate once transplanted. Here we describe a method (1) effective in obtaining human muscle precursor cells both from fresh and frozen biopsies coming from different muscles, (2) selective to yield cells uniformly positive for CD56 and negative for CD34 without FACS sorting, (3) reliable in maintaining proliferative and in vitro differentiative capacity up to passage 10
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