1,728 research outputs found
Condrosarcoma metatarsiano: aportación de un caso
Se presenta un caso de condrosarcoma de bajo grado de malignidad, de localización
y evolución inusual. Se revisa la literatura y los criterios disponibles en la actualidad
para el diagnóstico de estas lesiones controvertidas tanto histológica como clínicamente.We report a low grade chondrosarcoma with atypical behaviour and localitation.
The main histologic features in the diagnosis of these controversial lesion are discussed
The VVV Templates Project. Towards an Automated Classification of VVV Light-Curves. I. Building a database of stellar variability in the near-infrared
Context. The Vista Variables in the V\'ia L\'actea (VVV) ESO Public Survey is
a variability survey of the Milky Way bulge and an adjacent section of the disk
carried out from 2010 on ESO Visible and Infrared Survey Telescope for
Astronomy (VISTA). VVV will eventually deliver a deep near-IR atlas with
photometry and positions in five passbands (ZYJHK_S) and a catalogue of 1-10
million variable point sources - mostly unknown - which require
classifications. Aims. The main goal of the VVV Templates Project, that we
introduce in this work, is to develop and test the machine-learning algorithms
for the automated classification of the VVV light-curves. As VVV is the first
massive, multi-epoch survey of stellar variability in the near-infrared, the
template light-curves that are required for training the classification
algorithms are not available. In the first paper of the series we describe the
construction of this comprehensive database of infrared stellar variability.
Methods. First we performed a systematic search in the literature and public
data archives, second, we coordinated a worldwide observational campaign, and
third we exploited the VVV variability database itself on (optically)
well-known stars to gather high-quality infrared light-curves of several
hundreds of variable stars. Results. We have now collected a significant (and
still increasing) number of infrared template light-curves. This database will
be used as a training-set for the machine-learning algorithms that will
automatically classify the light-curves produced by VVV. The results of such an
automated classification will be covered in forthcoming papers of the series.Comment: 12 pages, 16 figures, 3 tables, accepted for publication in A&A. Most
of the data are now accessible through http://www.vvvtemplates.org
Photoprotective responses of three intertidal Antarctic macroalgae to short-term temperature stress
The Antarctic Peninsula is experiencing one of the highest warming rates globally. In polar regions, macroalgae thrive under extreme environmental conditions, which could worsen because of future climate change scenarios, including increased ultraviolet exposure, extremely low light availability, and fluctuating temperatures, particularly in the intertidal zones. To investigate the potential role of photoprotective and antioxidant mechanisms in response to future increases in sea surface temperatures caused by climate change, we conducted laboratory experiments using three intertidal macroalgae model species: Adenocystis utricularis (Ochrophyta, Phaeophyceae), Pyropia endiviifolia (Rhodophyta, Bangiophyceae), and Monostroma hariotii (Chlorophyta, Ulvophyceae). These algae were collected in Punta Artigas (King George Island, Antarctica) and acclimated at 2°C for 48 h. They were then assessed in laboratory experiments for up to 5 days under two treatments: (1) control conditions at 2°C and (2) elevated tem.perature conditions at 8°C, representing the most negative increment in SSTs estimated by the end of the 21st century. Carbon, nitrogen, pigments (chlorophylls and carotenoids), mycosporine-like amino acids (MAAs), and phenolic compounds were quantified after 3 and 5 days of exposure. For M. hariotii, elevated temperatures led to an increase in the C/N ratio, total antioxidant capacity, and levels of nitrogen, total carotenoids, chlorophyll-a, pigments (chlorophyll-b and violaxanthin), and phenolic compounds. For A. utricularis, elevated temperatures led to elevated C/N ratio and levels of chlorophyll-a and carotenoids (fucoxanthin and β-carotene). For P. endiviifolia, elevated temperatures resulted in elevated levels of carotenoids (lutein and β-carotene), phenolic compounds, and MAAs (porphyra-334, shinorine, and palythine). Thus, our study suggests that increasing water temperatures due to global warming can enhance the photoprotective abilities of three Antarctic intertidal macroalgae (M. hariotii, A. utricularis, and P. endiviifolia), with each species showing specific responses.Financial and logistical support were granted by the Projects INACH N° RG_10_18 and RT_09_16 granted to PC-P and CS, respectively
Biomarkers of the Endocannabinoid System in Substance Use Disorders
Despite substance use disorders (SUD) being one of the leading causes of disability and mortality globally, available therapeutic approaches remain ineffective. The difficulty in accurately characterizing the neurobiological mechanisms involved with a purely qualitative diagnosis is an obstacle to improving the classification and treatment of SUD. In this regard, identifying central and peripheral biomarkers is essential to diagnosing the severity of drug dependence, monitoring therapeutic efficacy, predicting treatment response, and enhancing the development of safer and more effective pharmacological tools. In recent years, the crucial role that the endocannabinoid system (ECS) plays in regulating the reinforcing and motivational properties of drugs of abuse has been described. This has led to studies characterizing ECS alterations after exposure to various substances to identify biomarkers with potential diagnostic, prognostic, or therapeutic utility. This review aims to compile the primary evidence available from rodent and clinical studies on how the ECS components are modified in the context of different substance-related disorders, gathering data from genetic, molecular, functional, and neuroimaging experimental approaches. Finally, this report concludes that additional translational research is needed to further characterize the modifications of the ECS in the context of SUD, and their potential usefulness in the necessary search for biomarkers
Lifetimes of excited states in P-, As- and Sb-
Radiative lifetimes of three elements of the nitrogen group have been
experimentally investigated at the Double ElectroStatic Ion Ring Experiment
(DESIREE) facility at Stockholm University. The experiments were performed
through selective laser photodetachment of excited states of P, As and
Sb ions stored in a cryogenic storage ring. The experimental results were
compared with theoretically predicted lifetimes, yielding a mixture of very
good agreements in some cases and large discrepancies in others. These results
are part of our efforts to map out the lifetimes of all excited states in
negative ions. This data can be used to benchmark atomic theories, in
particularly with respect to the degree of electron correlation that is
incorporated in various theoretical models
Report of a new mutation in CYBB gene in two patients with X linked chronic granulomatous disease
Background: The X-linked form of chronic granulomatous disease (CGD) is a primary immunodeficiency that affects phagocytes of the innate immune system and is characterized by an increased susceptibility to severe bacterial and fungal infections. It is caused by mutations in the CYBB gene, which encodes the 91-kD subunit of phagocyte NADPH oxidase. Aim: To identify the mutation in the CYBB gene in two unrelated patients from Chile with, the diagnosis of X-linked CGD and their families. Patients and methods: The molecular genetic defects of two unrelated patients from Chile with X-linked CGD caused by defects in the CYBB gene were investigated. The underlying mutation was investigated by single strand conformation polymorphism (SSCP) analysis of PCR-amplified genomic DNA and by sequencing of the affected gene region. Results: We found an insertion c.1267_1268insA in exon 10 leading to a frameshift mutation. This mutation is a novel report. We also identified a splice site mutation in the other patient, that presented a c.1326 +1 G > A substitution in intron 10. The mutation was also detectable in his heterozygous mother. Conclusions: This is the first report of the clinical and molecular characterization of Chilean patients with mutations in CYBB gene (Rev Med Chile 2006; 134: 965-72).134896597
Economic impact of infections and antibiotics
In this chapter, we review several aspects with respect to the burden of infectious diseases, its impact in morbidity and mortality, and its economic burden. Furthermore, we referenced the actual situation with relation to the use of antimicrobial, the resistance problem and misuse of antibiotic, and the economic impact in the health systems
[report Of A New Mutation In Cybb Gene In Two Patients With X Linked Chronic Granulomatous Disease].
The X-linked form of chronic granulomatous disease (CGD) is a primary immunodeficiency that affects phagocytes of the innate immune system and is characterized by an increased susceptibility to severe bacterial and fungal infections. It is caused by mutations in the CYBB gene, which encodes the 91-kD subunit of phagocyte NADPH oxidase. To identify the mutation in the CYBB gene in two unrelated patients from Chile with the diagnosis of X-linked CGD and their families. The molecular genetic defects of two unrelated patients from Chile with X-linked CGD caused by defects in the CYBB gene were investigated. The underlying mutation was investigated by single strand conformation polymorphism (SSCP) analysis of PCR-amplified genomic DNA and by sequencing of the affected gene region. We found an insertion c.1267_1268insA in exon 10 leading to a frameshift mutation. This mutation is a novel report. We also identified a splice site mutation in the other patient, that presented a c.1326 +1 G>A substitution in intron 10. The mutation was also detectable in his heterozygous mother. This is the first report of the clinical and molecular characterization of Chilean patients with mutations in CYBB gene.134965-7
Autoionization from the plasmon resonance in isolated 1-cyanonaphthalene
Polycyclic aromatic hydrocarbons have widely been conjectured to be ubiquitous in space, as supported by the recent discovery of two isomers of cyanonaphthalene, indene, and 2-cyanoindene in the Taurus molecular cloud-1 using radioastronomy. Here, the photoionization dynamics of 1-cyanonaphthalene (1-CNN) are investigated using synchrotron radiation over the hν = 9.0–19.5 eV range, revealing that prompt autoionization from the plasmon resonance dominates the photophysics for hν = 11.5–16.0 eV. Minimal photo-induced dissociation, whether originating from an excited state impulsive bond rupture or through internal conversion followed by a statistical bond cleavage process, occurs over the microsecond timescale (as limited by the experimental setup). The direct photoionization cross section and photoelectron angular distributions are simulated using an ezDyson model combining Dyson orbitals with Coulomb wave photoejection. When considering these data in conjunction with recent radiative cooling measurements on 1-CNN+, which showed that cations formed with up to 5 eV of internal energy efficiently stabilize through recurrent fluorescence, we conclude that the organic backbone of 1-CNN is resilient to photodestruction by VUV and soft XUV radiation. These dynamics may prove to be a common feature for the survival of small polycyclic aromatic hydrocarbons in space, provided that the cations have a suitable electronic structure to support recurrent fluorescence
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