610 research outputs found
Transcriptional role of cyclin D1 in development revealed by a “genetic-proteomic” screen
Author manuscript: 2010 September 22.Cyclin D1 belongs to the core cell cycle machinery, and it is frequently overexpressed in human cancers[superscript 1, 2]. The full repertoire of cyclin D1 functions in normal development and oncogenesis is unclear at present. Here we developed Flag- and haemagglutinin-tagged cyclin D1 knock-in mouse strains that allowed a high-throughput mass spectrometry approach to search for cyclin D1-binding proteins in different mouse organs. In addition to cell cycle partners, we observed several proteins involved in transcription. Genome-wide location analyses (chromatin immunoprecipitation coupled to DNA microarray; ChIP-chip) showed that during mouse development cyclin D1 occupies promoters of abundantly expressed genes. In particular, we found that in developing mouse retinas—an organ that critically requires cyclin D1 function[superscript 3, 4]—cyclin D1 binds the upstream regulatory region of the Notch1 gene, where it serves to recruit CREB binding protein (CBP) histone acetyltransferase. Genetic ablation of cyclin D1 resulted in decreased CBP recruitment, decreased histone acetylation of the Notch1 promoter region, and led to decreased levels of the Notch1 transcript and protein in cyclin D1-null (Ccnd1-/-) retinas. Transduction of an activated allele of Notch1 into Ccnd1-/- retinas increased proliferation of retinal progenitor cells, indicating that upregulation of Notch1 signalling alleviates the phenotype of cyclin D1-deficiency. These studies show that in addition to its well-established cell cycle roles, cyclin D1 has an in vivo transcriptional function in mouse development. Our approach, which we term ‘genetic–proteomic’, can be used to study the in vivo function of essentially any protein
Description and analysis of novelties introduced in DCASE Task 4 2022 on the baseline system
The aim of the Detection and Classification of Acoustic Scenes and Events
Challenge Task 4 is to evaluate systems for the detection of sound events in
domestic environments using an heterogeneous dataset. The systems need to be
able to correctly detect the sound events present in a recorded audio clip, as
well as localize the events in time. This year's task is a follow-up of DCASE
2021 Task 4, with some important novelties. The goal of this paper is to
describe and motivate these new additions, and report an analysis of their
impact on the baseline system. We introduced three main novelties: the use of
external datasets, including recently released strongly annotated clips from
Audioset, the possibility of leveraging pre-trained models, and a new energy
consumption metric to raise awareness about the ecological impact of training
sound events detectors. The results on the baseline system show that leveraging
open-source pretrained on AudioSet improves the results significantly in terms
of event classification but not in terms of event segmentation
Why Are Outcomes Different for Registry Patients Enrolled Prospectively and Retrospectively? Insights from the Global Anticoagulant Registry in the FIELD-Atrial Fibrillation (GARFIELD-AF).
Background: Retrospective and prospective observational studies are designed to reflect real-world evidence on clinical practice, but can yield conflicting results. The GARFIELD-AF Registry includes both methods of enrolment and allows analysis of differences in patient characteristics and outcomes that may result. Methods and Results: Patients with atrial fibrillation (AF) and ≥1 risk factor for stroke at diagnosis of AF were recruited either retrospectively (n = 5069) or prospectively (n = 5501) from 19 countries and then followed prospectively. The retrospectively enrolled cohort comprised patients with established AF (for a least 6, and up to 24 months before enrolment), who were identified retrospectively (and baseline and partial follow-up data were collected from the emedical records) and then followed prospectively between 0-18 months (such that the total time of follow-up was 24 months; data collection Dec-2009 and Oct-2010). In the prospectively enrolled cohort, patients with newly diagnosed AF (≤6 weeks after diagnosis) were recruited between Mar-2010 and Oct-2011 and were followed for 24 months after enrolment. Differences between the cohorts were observed in clinical characteristics, including type of AF, stroke prevention strategies, and event rates. More patients in the retrospectively identified cohort received vitamin K antagonists (62.1% vs. 53.2%) and fewer received non-vitamin K oral anticoagulants (1.8% vs . 4.2%). All-cause mortality rates per 100 person-years during the prospective follow-up (starting the first study visit up to 1 year) were significantly lower in the retrospective than prospectively identified cohort (3.04 [95% CI 2.51 to 3.67] vs . 4.05 [95% CI 3.53 to 4.63]; p = 0.016). Conclusions: Interpretations of data from registries that aim to evaluate the characteristics and outcomes of patients with AF must take account of differences in registry design and the impact of recall bias and survivorship bias that is incurred with retrospective enrolment. Clinical Trial Registration: - URL: http://www.clinicaltrials.gov . Unique identifier for GARFIELD-AF (NCT01090362)
LIFESTYLE ASSESSMENT AND IMPROVEMENT WITH FOCUS ON LEISURE TIME PHYSICAL ACTIVITY AMONG UNIVERSITY STUDENTS: THE #STUDIOXLAVITA PROJECT
INTRODUCTION: Sedentariness, smoking, alcohol abuse and unbalanced feeding are harmful for health, leading to chronic diseases and
increasing mortality rate. For young adults, University is a new social and cultural context: parents’ imprinting could be easily altered, new
lifestyles take shape and personal choices emerge. Intervention programmes to advance awareness on harmful lifestyle and promote
healthy habits are essential. The #studioxlavita project, launched in 2016 by the University of Brescia with these purposes, investigated
students’ lifestyle, with special emphasis on physical activity .
METHODS: We developed two consecutive facultative surveys, of 15 <1st level> and 52 items <2nd level>, addressed to all the University’s
students. Questions were about leisure time physical activity , use of fitness technology, relationship with friends, classmates and parents,
feed, physical appearance, body self-perception, physical and mental health, use of certain substances or products , night-time rest and
beliefs concerning healthy behaviours. In the 2nd level survey we also adopted the Kessler Psychological Distress Scale and the short
form of the International Physical Activity Questionnaire to estimate the amount of PA carried out in the last 7 days. Students who filled in
both questionnaires received a personal report including the aggregate data analysis, a comparison with other investigations and indications
about healthy habits, according to recommendations and guidelines.
RESULTS: 3,436 out of 15,688 students filled in the1st level survey. Of them, 778 accepted to participate in the 2nd level survey, and 456
completed it. 1st level survey revealed that 72% of the students practised LTPA <45% regularly and 27% occasionally>. LTPA is largely
performed <44% of the student> in non-competitive form, with recreational and/or health purposes. According to IPAQ-SF categorical
score, 24%, 34% and 42% of the students performed low, moderate and high levels of PA, respectively. In 2st level survey, 76% of the
students wished to practise more PA; 42% would participate in practical sport courses.
CONCLUSION: University is an ideal setting for promoting lifestyle change among a captive audience. Intervention programs to increment
PA are acclaimed by students. The students from University of Brescia reported higher LTPA practice than the national average people
between 18 and 34 years <47%, data from Italian National Institute of Statistics, 2015>, although this parameter was assessed with
different methods
EFFECTS OF PHYSICAL ACTIVITY PROMOTION AMONG UNIVERSITY STUDENTS: THE #STUDIOXLAVITA PROJECT
INTRODUCTION: Sedentariness is a major health problem in our time and physical activity promotion is an imperative commitment for
healthcare systems. Recommendations from WHO indicate a minimum of 150 minutes of moderate intensity aerobic exercise as weekly
standard for adults. Strategies to increment PA practice are implemented in different settings, such as house care, school, University and
workplace. The project #studioxlavita <#SXLV> was launched by the University of Brescia in 2016 with the aim of collecting data about
undergraduates lifestyle and encourage healthy behaviours. In particular we focused on PA assessment and promotion in a Universitybased
setting.
METHODS: Two consecutive surveys were sent to all students . Q0 included the short form of the International Physical Activity Questionnaire
, the Kessler Psychological Distress Scale and additional questions on several lifestyle aspects. Among responders, we selected 40
students who agreed to take part in one of the following 15-week practical sport courses: ultimate frisbee, muscle strengthening and
dance fitness. Before and after being engaged in practical sport courses, students underwent cardiopulmonary exercise test and skinfold
thickness measurements, in order to assess peak oxygen consumption and percent body fat . Finally, to assess possible lifestyle changes,
we sent them additional surveys at the end of the practical sport courses and 30 days after . Paired t-test was used to analyse significant
differences.
RESULTS: 27 students <16 female, 11 male; age: 22.7±3.7> concluded sport activity courses and filled in Q1. Of them, 20 completed also
Q2. Overall courses attendance was 57%. At T1 , normalized Q̇O2peak increased with respect to T0 <37.0±6.9 vs 35.2±7.4 ml/min/Kg,
p=0.03>. Conversely, percent body fat decreased <16.5±6.4 vs 18.3±7.5, p=0.01>. In Q1, 20 students declared to have a more active
lifestyle since the beginning of the courses. In Q2, IPAQ-SF-derived total weekly energy expenditure was higher than in Q0, although not
significant <5,839 ±7,035 MET*min vs 2,770±2,457 MET*min, p=0.1>. Q2 showed a reduced K6 scale score with respect to Q0 <13.8±4.6
vs 15.8±4.9, p=0.03>.
CONCLUSION: With the sport activity courses established in #SXLV we gave students the opportunity to comply with WHO recommendations.
After courses, they appeared to practice more PA, have a higher maximal aerobic capacity, a lower percent body fat and a lower
grade of psychological distress than before courses. Simple activities as those proposed by #SXLV are sufficient to reduce sedentariness
and improve the quality of life of student
Spectral index-flux relation for investigating the origins of steep decay in γ-ray bursts
γ-ray bursts (GRBs) are short-lived transients releasing a large amount of energy (10 − 10 erg) in the keV-MeV energy range. GRBs are thought to originate from internal dissipation of the energy carried by ultra-relativistic jets launched by the remnant of a massive star’s death or a compact binary coalescence. While thousands of GRBs have been observed over the last thirty years, we still have an incomplete understanding of where and how the radiation is generated in the jet. Here we show a relation between the spectral index and the flux found by investigating the X-ray tails of bright GRB pulses via time-resolved spectral analysis. This relation is incompatible with the long standing scenario which invokes the delayed arrival of photons from high-latitude parts of the jet. While the alternative scenarios cannot be firmly excluded, the adiabatic cooling of the emitting particles is the most plausible explanation for the discovered relation, suggesting a proton-synchrotron origin of the GRB emission.The research leading to these results has received funding from the European Union’s Horizon 2020 Programme under the AHEAD2020 project (Grant agreement n. 871158). G. Ghir. acknowledges the support from the ASI-Nustar Grant (1.05.04.95). M.B., P.D., and G.G. acknowledge support from PRIN-MIUR 2017 (Grant 20179ZF5KS). G.O. acknowledges financial contribution from the agreement ASI-INAF n.2017-14-H.0. S.A. acknowledges the PRIN-INAF “Towards the SKA and CTA era: discovery, localization, and physics of transient sources” and the ERC Consolidator Grant “MAGNESIA” (nr. 817661). M.G.B. and P.D. acknowledge ASI Grant I/004/11/3. O.S.S. acknowledges the INAF-Prin 2017 (1.05.01.88.06) and the Italian Ministry for University and Research Grant “FIGARO” (1.05.06.13) for support. G.O. and S.R. are thankful to INAF—Osservatorio Astronomico di Brera for kind hospitality during the completion of this work. This work made use of data supplied by the UK Swift Science Data Centre at the University of Leicester
Cooperation between Wnt and Notch signalling in human breast cancer
The Wnt and Notch signalling pathways play major roles in mammary gland development and tumourigenesis. During development, these pathways have opposing effects. However, in a recent paper Ayyanan and coworkers show that expression of Wnt1 is sufficient to transform primary human mammary epithelial cells, and that this is in part due to activation of the Notch pathway. This indicates that during tumourigenesis the two pathways cooperate. Here we ask why activation of Wnt signalling alone is sufficient to cause transformation; whether there is evidence for inhibitory crosstalk between the pathways during tumourigenesis; and whether cooperation between these pathways occurs in other forms of cancer
The Notch pathway in ovarian carcinomas and adenomas
Elements of the Notch pathway regulate differentiation; we investigated the expression of such elements in epithelial ovarian tumours. A total of 32 ovarian tumour samples (17 adenocarcinomas, three borderline tumours, 12 adenomas), two human ovarian cancer (A2780, OVCAR3), and one ovarian surface (IOSE 144) cell lines were analysed. The expression of Notch pathway elements was assessed by RT–PCR, real-time PCR (Notch 1), and by immunoblots (Notch 1 extracellular domain (EC), HES1). The proliferation and colony formation of A2780 cells were measured after stable transfection with activated Notch 1 (intracellular domain). Jagged 2, Delta-like-1, Manic Fringe, and TSL1 were expressed more frequently in adenocarcinomas whereas Deltex, Mastermind, and Radical Fringe were more frequent in adenomas. Quantitative PCR revealed decreased Notch 1 mRNA in ovarian adenocarcinomas compared with adenomas. The expression of Notch 1-EC protein was similar in benign and malignant tumours. HES1 protein was strongly expressed in 18/19 ovarian cancers and borderline tumours but not in adenomas. Transfecting A2780 cells with active Notch 1-IC resulted in a proliferative and colony formation advantage compared to mock transfected cells. Thus, Notch pathway elements are expressed in ovarian epithelial tumours and some of them are differentially expressed between adenomas and carcinomas. The Notch pathway could be a target for the development of therapies for ovarian cancer
Panning for gold, but finding helium: discovery of the ultra-stripped supernova SN2019wxt from gravitational-wave follow-up observations
We present the results from multi-wavelength observations of a transient
discovered during the follow-up of S191213g, a gravitational wave (GW) event
reported by the LIGO-Virgo Collaboration as a possible binary neutron star
merger in a low latency search. This search yielded SN2019wxt, a young
transient in a galaxy whose sky position (in the 80\% GW contour) and distance
(150\,Mpc) were plausibly compatible with the localisation uncertainty of
the GW event. Initially, the transient's tightly constrained age, its
relatively faint peak magnitude (\,mag) and the band
decline rate of \,mag per 5\,days appeared suggestive of a compact
binary merger. However, SN2019wxt spectroscopically resembled a type Ib
supernova, and analysis of the optical-near-infrared evolution rapidly led to
the conclusion that while it could not be associated with S191213g, it
nevertheless represented an extreme outcome of stellar evolution. By modelling
the light curve, we estimated an ejecta mass of , with
Ni comprising of this. We were broadly able to reproduce its
spectral evolution with a composition dominated by helium and oxygen, with
trace amounts of calcium. We considered various progenitors that could give
rise to the observed properties of SN2019wxt, and concluded that an
ultra-stripped origin in a binary system is the most likely explanation.
Disentangling electromagnetic counterparts to GW events from transients such as
SN2019wxt is challenging: in a bid to characterise the level of contamination,
we estimated the rate of events with properties comparable to those of
SN2019wxt and found that such event per week can occur within the
typical GW localisation area of O4 alerts out to a luminosity distance of
500\,Mpc, beyond which it would become fainter than the typical depth of
current electromagnetic follow-up campaigns.Comment: By the ENGRAVE collaboration (engrave-eso.org). 35 pages, 20 figures,
final version accepted by A&
Notch and Senescence.
Cellular senescence, previously thought of as an autonomous tumour suppressor mechanism, is emerging as a phenotype and effector present throughout the life of an organism from embryogenesis to senile decline. Senescent cells have powerful non-autonomous effects upon multiple players within their microenvironment mainly through their secretory phenotype. How senescent cells co-ordinate numerous, sometimes functionally contrasting outputs through their secretome had previously been unclear. The Notch pathway, originally identified for its involvement in Drosophila wing development, has more recently been found to underpin diverse effects in human cancer. Here we discuss recent findings that suggest that Notch is intimately involved in the development of senescence and how it acts to co-ordinate the composition and functional effects of the senescence secretome. We also highlight the complex physical and functional interplay between Notch and p53, critical to both senescence and cancer. Understanding the interplay between Notch, p53 and senescence could allow us develop the therapeutics of the future for cancer and ageing
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