58 research outputs found
Incubation parameters, offspring growth, and behavioral adaptations to heat stress of Black Skimmers (Rynchops niger) in a Neotropical inland colony (Aves, Charadriiformes, Laridae)
This study focuses on incubation parameters, egg morphometrics, and body mass development, hatching, and behavioral adaptations to heat stress within a colony of freshwater-breeding Black Skimmers (Rynchops niger) located in the private nature reserve of Serviço Social do ComĂ©rcio (SESC) in the northern Pantanal, Mato Grosso, Brazil. Temperatures of nest, eggs, and surface substratum, as well as the development of embryos, were surveyed using thermal imaging, a method allowing digital recording from a distance and in a fraction of the time of traditional measuring techniques. The mean egg dimensions (n = 71) were 4.48 (± 0.13) Ă 3.27 (± 0.07) cm; the mean mass at hatching was 24.3 (± 1.9) g, with a significant decrease over incubation time. The mean surface temperature of eggs varied from 30.9â to 39.7â, while the sand surface temperature was 20â at 06:00 h, rising to 47.7â at 11:00 h. There was a significant increase (7%) in egg surface temperature throughout incubation. Incubation-bout durations (n = 2108) were correlated with the microclimatic conditions of the substratum, becoming shorter with increasing sand-surface temperature around midday. Egg hatching lasted one day, and siblings hatched no more than 24 h apart. The mean body mass on Day 1 after hatching was 16.8 (± 1.6) g (n = 6). Three days after hatching, chicks moved to new sand depressions provided by parents near the original nest, where they remained motionless or tried to hide under riparian vegetation. The single chick that fledged had a growth rate of K = 0.117 and a tâââââ value of 37.3 days. On Day 7, dorsal pintail feathers and primaries appeared, which were open on Day 15. After 14 days, the chick was able to regulate its body temperature, and no more feeding by parental birds during the daytime was observed. On Day 21, the immature plumage was fully developed. Fledging was completed on Day 27. Our study demonstrates that thermal imaging is a useful method of surveying egg and embryo development in the Black Skimmer, reducing nest disturbance and observation efforts
Defining the role of real-world data in cancer clinical research: The position of the European Organisation for Research and Treatment of Cancer
The emergence of the precision medicine paradigm in oncology has led to increasing interest in the integration of real-world data (RWD) into cancer clinical research. As sources of real-world evidence (RWE), such data could potentially help address the uncertainties that surround the adoption of novel anticancer therapies into the clinic following their investigation in clinical trials. At present, RWE-generating studies which investigate antitumour interventions seem to primarily focus on collecting and analysing observational RWD, typically forgoing the use of randomisation despite its methodological benefits. This is appropriate in situations where randomised controlled trials (RCTs) are not feasible and non-randomised RWD analyses can offer valuable insights. Nevertheless, depending on how they are designed, RCTs have the potential to produce strong and actionable RWE themselves. The choice of which methodology to employ for RWD studies should be guided by the nature of the research question they are intended to answer. Here, we attempt to define some of the questions that do not necessarily require the conduct of RCTs. Moreover, we outline the strategy of the European Organisation for Research and Treatment of Cancer (EORTC) to contribute to the generation of robust and high-quality RWE by prioritising the execution of pragmatic trials and studies set up according to the trials-within-cohorts approach. If treatment allocation cannot be left up to random chance due to practical or ethical concerns, the EORTC will consider undertaking observational RWD research based on the target trial principle. New EORTC-sponsored RCTs may also feature concurrent prospective cohorts composed of off-trial patients
Defining the role of real-world data in cancer clinical research:The position of the European Organisation for Research and Treatment of Cancer
The emergence of the precision medicine paradigm in oncology has led to increasing interest in the integration of real-world data (RWD) into cancer clinical research. As sources of real-world evidence (RWE), such data could potentially help address the uncertainties that surround the adoption of novel anticancer therapies into the clinic following their investigation in clinical trials. At present, RWE-generating studies which investigate antitumour interventions seem to primarily focus on collecting and analysing observational RWD, typically forgoing the use of randomisation despite its methodological benefits. This is appropriate in situations where randomised controlled trials (RCTs) are not feasible and non-randomised RWD analyses can offer valuable insights. Nevertheless, depending on how they are designed, RCTs have the potential to produce strong and actionable RWE themselves. The choice of which methodology to employ for RWD studies should be guided by the nature of the research question they are intended to answer. Here, we attempt to define some of the questions that do not necessarily require the conduct of RCTs. Moreover, we outline the strategy of the European Organisation for Research and Treatment of Cancer (EORTC) to contribute to the generation of robust and high-quality RWE by prioritising the execution of pragmatic trials and studies set up according to the trials-within-cohorts approach. If treatment allocation cannot be left up to random chance due to practical or ethical concerns, the EORTC will consider undertaking observational RWD research based on the target trial principle. New EORTC-sponsored RCTs may also feature concurrent prospective cohorts composed of off-trial patients
Unusual presentation of central nervous system metastases: mechanisms of spread and radiological findings
O conhecimento e o ensino sobre doenças sexualmente transmissĂveis entre universitĂĄrios
Expression and pharmacological inhibition of TrkB and EGFR in glioblastoma
A member of the Trk family of neurotrophin receptors, tropomyosin receptor kinase B (TrkB, encoded by the NTRK2 gene) is an increasingly important target in various cancer types, including glioblastoma (GBM). EGFR is among the most frequently altered oncogenes in GBM, and EGFR inhibition has been tested as an experimental therapy. Functional interactions between EGFR and TrkB have been demonstrated. In the present study, we investigated the role of TrkB and EGFR, and their interactions, in GBM. Analyses of NTRK2 and EGFR gene expression from The Cancer Genome Atlas (TCGA) datasets showed an increase in NTRK2 expression in the proneural subtype of GBM, and a strong correlation between NTRK2 and EGFR expression in glioma CpG island methylator phenotype (G-CIMP+) samples. We showed that when TrkB and EGFR inhibitors were combined, the inhibitory effect on A172 human GBM cells was more pronounced than when either inhibitor was given alone. When U87MG GBM cells were xenografted into the flank of nude mice, tumor growth was delayed by treatment with TrkB and EGFR inhibitors, given alone or combined, only at specific time points. Intracranial GBM growth in mice was not significantly affected by drug treatments. Our findings indicate that correlations between NTRK2 and EGFR expression occur in specific GBM subgroups. Also, our results using cultured cells suggest for the first time the potential of combining TrkB and EGFR inhibition for the treatment of GBM
Multi-messenger Observations of a Binary Neutron Star Merger
On 2017 August 17 a binary neutron star coalescence candidate (later
designated GW170817) with merger time 12:41:04 UTC was observed through
gravitational waves by the Advanced LIGO and Advanced Virgo detectors.
The Fermi Gamma-ray Burst Monitor independently detected a gamma-ray
burst (GRB 170817A) with a time delay of ⌠1.7 {{s}} with respect to
the merger time. From the gravitational-wave signal, the source was
initially localized to a sky region of 31 deg2 at a
luminosity distance of {40}-8+8 Mpc and with
component masses consistent with neutron stars. The component masses
were later measured to be in the range 0.86 to 2.26 {M}ÈŻ
. An extensive observing campaign was launched across the
electromagnetic spectrum leading to the discovery of a bright optical
transient (SSS17a, now with the IAU identification of AT 2017gfo) in NGC
4993 (at ⌠40 {{Mpc}}) less than 11 hours after the merger by the
One-Meter, Two Hemisphere (1M2H) team using the 1 m Swope Telescope. The
optical transient was independently detected by multiple teams within an
hour. Subsequent observations targeted the object and its environment.
Early ultraviolet observations revealed a blue transient that faded
within 48 hours. Optical and infrared observations showed a redward
evolution over âŒ10 days. Following early non-detections, X-ray and
radio emission were discovered at the transientâs position ⌠9
and ⌠16 days, respectively, after the merger. Both the X-ray and
radio emission likely arise from a physical process that is distinct
from the one that generates the UV/optical/near-infrared emission. No
ultra-high-energy gamma-rays and no neutrino candidates consistent with
the source were found in follow-up searches. These observations support
the hypothesis that GW170817 was produced by the merger of two neutron
stars in NGC 4993 followed by a short gamma-ray burst (GRB 170817A) and
a kilonova/macronova powered by the radioactive decay of r-process
nuclei synthesized in the ejecta.</p
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