496 research outputs found
Carcinogenic potential of metal nanoparticles in BALB/3T3 cell transformation assay.
Metal-based nanoparticles (NPs), are currently used in many application fields including consumer products, pharmaceuticals, and biomedical treatments. In spite to their wide applications, an in-depth study of their potential toxic effects is still lacking. The aim of the present research was to investigate the potential initiator or promoter-like activity of different metallic NPs such as gold, iron, cobalt, and cerium using the Balb/3T3 two-stage transformation assay. The results indicated that all the selected metallic NPs, except for cobalt, when used as initiators did not induce any transformation in Balb/3T3 cell line. Moreover, Au and Fe3 O4 NPs, when used in place of the tumor promoter treatment TPA, increased significantly the number of Foci/dish as compared to the MCA treatment alone. The number of Foci/dish was 2.6 for Au NPs and 2.13 for Fe3 O4 ones, similar to those obtained by the positive control treatment (MCA + TPA), whereas 1.27 for MCA treatment alone. On the contrary, CeO2 NPs did not show any difference in the number of Foci/dish, as compared to MCA alone, but it decreased the number of foci by 65% in comparison to the positive control (MCA + TPA). As expected, cobalt NPs showed an increased cytotoxicity and only a few surviving cells were found at the time of analysis showing a number of Foci/dish of 0.13. For the first time, our data clearly showed that Au and Fe3 O4 NPs act as promoters in the two stage transformational assay, suggesting the importance to fully investigate the NPs carcinogenic potential with different models
Democratizing Innovation. A Geo-Entrepreneurial Analysis and Approach Through the Company Democracy Model
Even that thinking, and innovative thinking, in particular, is supposed to be borderless and unbiased, it seems that most of the innovations globally derive from regions that have built a brand name on it. This limits the opportunities to bright ideas form bright people outside the innovation hubs, resulting in a general loss of intellectual capital for the global economy. This paper aims to democratize innovation by redefining geo-entrepreneurship through a reverse innovation framework that exposes the hidden intellectual capital around the world, evaluates innovation drives and opportunities and empowers the development, commercialization and utilization of innovation. Based on the Company Democracy Model the proposed framework impacts reversely national brain-drain contributes to innovation scouting, strategic partnerships, and redistributes success opportunities. This geo-entrepreneurial approach identifies innovation potential globally, reduces inequalities among all those who can and want to create opportunities regardless of where innovation takes place and by whom
A mediation approach to understanding socio-economic inequalities in maternal health-seeking behaviours in Egypt.
BACKGROUND: The levels and origins of socio-economic inequalities in health-seeking behaviours in Egypt are poorly understood. This paper assesses the levels of health-seeking behaviours related to maternal care (antenatal care [ANC] and facility delivery) and their accumulation during pregnancy and childbirth. Secondly, it explores the mechanisms underlying the association between socio-economic position (SEP) and maternal health-seeking behaviours. Thirdly, it examines the effectiveness of targeting of free public ANC and delivery care. METHODS: Data from the 2008 Demographic and Health Survey were used to capture two latent constructs of SEP: individual socio-cultural capital and household-level economic capital. These variables were entered into an adjusted mediation model, predicting twelve dimensions of maternal health-seeking; including any ANC, private ANC, first ANC visit in first trimester, regular ANC (four or more visits during pregnancy), facility delivery, and private delivery. ANC and delivery care costs were examined separately by provider type (public or private). RESULTS: While 74.2% of women with a birth in the 5-year recall period obtained any ANC and 72.4% delivered in a facility, only 48.8% obtained the complete maternal care package (timely and regular facility-based ANC as well as facility delivery) for their most recent live birth. Both socio-cultural capital and economic capital were independently positively associated with receiving any ANC and delivering in a facility. The strongest direct effect of socio-cultural capital was seen in models predicting private provider use of both ANC and delivery. Despite substantial proportions of women using public providers reporting receipt of free care (ANC: 38%, delivery: 24%), this free-of-charge public care was not effectively targeted to women with lowest economic resources. CONCLUSIONS: Socio-cultural capital is the primary mechanism leading to inequalities in maternal health-seeking in Egypt. Future studies should therefore examine the objective and perceived quality of care from different types of providers. Improvements in the targeting of free public care could help reduce the existing SEP-based inequalities in maternal care coverage in the short term
Robotic-assisted, laparoscopic, and open radical cystectomy: surgical data of 1400 patients from The Italian Radical Cystectomy Registry on intraoperative outcomes
Introduction: The Italian Radical Cystectomy Registry (Registro Italiano Cistectomie - RIC) aimed to analyse outcomes of a multicenter series of patients treated with radical cystectomy (RC) for bladder cancer.
Material and methods: An observational, prospective, multicenter, cohort study was performed to collect data from RC and urinary diversion via open (ORC), laparoscopic (LRC), or robotic-assisted (RARC) techniques performed in 28 Italian Urological Departments. The enrolment was planned from January 2017 to June 2020 (goal: 1000 patients), with a total of 1425 patients included. Chi-square and t-tests were used for categorical and continuous variables. All tests were 2-sided, with a significance level set at p <0.05.
Results: Overall median operative-time was longer in RARCs (390 minutes, IQR 335-465) than ORCs (250, 217-309) and LRCs (292, 228-350) (p <0.001). Lymph node dissection (LND) was performed more frequently in RARCs (97.1%) and LRCs (93.5%) than ORCs (85.6%) (p <0.001), with extended-LND performed 2-fold more frequently in RARCs (61.6%) (p <0.001). The neobladder rate was significantly higher (more than one-half) in RARCs. The median estimated blood loss (EBL) rate was lower in RARCs (250 ml, 165-400) than LRCs (330, 200-600) and ORCs (400, 250-600) (p <0.001), with intraoperative blood transfusion rates of 11.4%, 21.7% and 35.6%, respectively (p <0.001). The conversion to open rate was slightly higher in RARCs (6.8%) than LRCs (4.3%). Intraoperative complications occurred in 1.3% of cases without statistically significant differences among the approaches.
Conclusions: Data from the RIC confirmed the need to collect as much data as possible in a multicenter manner. RARCs proves to be feasible with perioperative complication rates that do not differ from the other approaches
iPTF17cw: An Engine-driven Supernova Candidate Discovered Independent of a Gamma-Ray Trigger
We present the discovery, classification, and radio-to-X-ray follow-up observations of iPTF17cw, a broad-lined (BL) type Ic supernova (SN) discovered by the intermediate Palomar Transient Factory (iPTF). Although it is unrelated to the gravitational wave trigger, this SN was discovered as a happy by-product of the extensive observational campaign dedicated to the follow-up of Advanced LIGO event GW 170104. The spectroscopic properties and inferred peak bolometric luminosity of iPTF17cw are most similar to the gamma-ray-burst (GRB)-associated SN, SN 1998bw, while the shape of the r-band light curve is most similar to that of the relativistic SN, SN 2009bb. Karl G. Jansky Very Large Array (VLA) observations of the iPTF17cw field reveal a radio counterpart ≈10 times less luminous than SN 1998bw, and with a peak radio luminosity comparable to that of SN 2006aj/GRB 060218 and SN 2010bh/GRB 100316D. Our radio observations of iPTF17cw imply a relativistically expanding outflow. However, further late-time observations with the VLA in its most extended configuration are needed to confirm fading of the iPTF17cw radio counterpart at all frequencies. X-ray observations carried out with Chandra reveal the presence of an X-ray counterpart with a luminosity similar to that of SN 2010bh/GRB 100316D. Searching the Fermi catalog for possible γ-rays reveals that GRB 161228B is spatially and temporally compatible with iPTF17cw. The similarity to SN 1998bw and SN 2009bb, the radio and X-ray detections, and the potential association with GRB 161228B all point to iPTF17cw being a new candidate member of the rare sample of optically discovered engine-driven BL-Ic SNe associated with relativistic ejecta
Observational and Physical Classification of Supernovae
This chapter describes the current classification scheme of supernovae (SNe).
This scheme has evolved over many decades and now includes numerous SN Types
and sub-types. Many of these are universally recognized, while there are
controversies regarding the definitions, membership and even the names of some
sub-classes; we will try to review here the commonly-used nomenclature, noting
the main variants when possible. SN Types are defined according to
observational properties; mostly visible-light spectra near maximum light, as
well as according to their photometric properties. However, a long-term goal of
SN classification is to associate observationally-defined classes with specific
physical explosive phenomena. We show here that this aspiration is now finally
coming to fruition, and we establish the SN classification scheme upon direct
observational evidence connecting SN groups with specific progenitor stars.
Observationally, the broad class of Type II SNe contains objects showing strong
spectroscopic signatures of hydrogen, while objects lacking such signatures are
of Type I, which is further divided to numerous subclasses. Recently a class of
super-luminous SNe (SLSNe, typically 10 times more luminous than standard
events) has been identified, and it is discussed. We end this chapter by
briefly describing a proposed alternative classification scheme that is
inspired by the stellar classification system. This system presents our
emerging physical understanding of SN explosions, while clearly separating
robust observational properties from physical inferences that can be debated.
This new system is quantitative, and naturally deals with events distributed
along a continuum, rather than being strictly divided into discrete classes.
Thus, it may be more suitable to the coming era where SN numbers will quickly
expand from a few thousands to millions of events.Comment: Extended final draft of a chapter in the "SN Handbook". Comments most
welcom
A genome-wide association study identifies protein quantitative trait loci (pQTLs)
There is considerable evidence that human genetic variation influences gene expression. Genome-wide studies have revealed that mRNA levels are associated with genetic variation in or close to the gene coding for those mRNA transcripts - cis effects, and elsewhere in the genome - trans effects. The role of genetic variation in determining protein levels has not been systematically assessed. Using a genome-wide association approach we show that common genetic variation influences levels of clinically relevant proteins in human serum and plasma. We evaluated the role of 496,032 polymorphisms on levels of 42 proteins measured in 1200 fasting individuals from the population based InCHIANTI study. Proteins included insulin, several interleukins, adipokines, chemokines, and liver function markers that are implicated in many common diseases including metabolic, inflammatory, and infectious conditions. We identified eight Cis effects, including variants in or near the IL6R (p = 1.8×10 -57), CCL4L1 (p = 3.9×10-21), IL18 (p = 6.8×10-13), LPA (p = 4.4×10-10), GGT1 (p = 1.5×10-7), SHBG (p = 3.1×10-7), CRP (p = 6.4×10-6) and IL1RN (p = 7.3×10-6) genes, all associated with their respective protein products with effect sizes ranging from 0.19 to 0.69 standard deviations per allele. Mechanisms implicated include altered rates of cleavage of bound to unbound soluble receptor (IL6R), altered secretion rates of different sized proteins (LPA), variation in gene copy number (CCL4L1) and altered transcription (GGT1). We identified one novel trans effect that was an association between ABO blood group and tumour necrosis factor alpha (TNF-alpha) levels (p = 6.8×10-40), but this finding was not present when TNF-alpha was measured using a different assay , or in a second study, suggesting an assay-specific association. Our results show that protein levels share some of the features of the genetics of gene expression. These include the presence of strong genetic effects in cis locations. The identification of protein quantitative trait loci (pQTLs) may be a powerful complementary method of improving our understanding of disease pathways. © 2008 Melzer et al
Real-time three-dimensional transthoracic echocardiography in daily practice: initial experience
<p>Abstract</p> <p>Aim of the work</p> <p>To evaluate the feasibility and possible additional value of transthoracic real-time three-dimensional echocardiography (RT3D-TTE) for the assessment of cardiac structures as compared to 2D-TTE.</p> <p>Methods</p> <p>320 patients (mean age 45 ± 8.4 years, 75% males) underwent 2D-TTE and RT3D-TTE using 3DQ-Q lab software for offline analysis. Volume quantification and functional assessment was performed in 90 patients for left ventricle and in 20 patients for right ventricle. Assessment of native (112 patients) and prosthetic (30 patients) valves morphology and functions was performed. RT3D-TTE was performed for evaluation of septal defects in 30 patients and intracardiac masses in 52 patients.</p> <p>Results</p> <p>RT3D-TTE assessment of left ventricle was feasible and reproducible in 86% of patients while for right ventricle, it was (55%). RT3D-TTE could define the surface anatomy of mitral valve optimally (100%), while for aortic and tricuspid was (88% and 81% respectively). Valve area could be planimetered in 100% for the mitral and in 80% for the aortic. RT3D-TTE provided a comprehensive anatomical and functional evaluation of prosthetic valves. RT3D-TTE enface visualization of septal defects allowed optimal assessment of shape, size, area and number of defects and evaluated the outcome post device closure. RT3D-TTE allowed looking inside the intracardiac masses through multiple sectioning, valuable anatomical delineation and volume calculation.</p> <p>Conclusion</p> <p>Our initial experience showed that the use of RT3D-TTE in the assessment of cardiac patients is feasible and allowed detailed anatomical and functional assessment of many cardiac disorders.</p
Bisphenol A exposure is associated with in vivo estrogenic gene expression in adults
addresses: Epidemiology and Public Health, Peninsula College of Medicine and Dentistry, University of Exeter, Exeter, United Kingdom.notes: PMCID: PMC3261992types: Journal Article; Research Support, N.I.H., Intramural; Research Support, Non-U.S. Gov'tEnvironmental Health Perspectives, 2011, Vol. 119, Issue 12, pp. 1788 – 1793 doi: 10.1289/ehp.1103809. Reproduced with permission from Environmental Health Perspectives, http://ehp.niehs.nih.gov/ Copyright ©2011 National Institute of Environmental Health SciencesBisphenol A (BPA) is a synthetic estrogen commonly used in polycarbonate plastic and resin-lined food and beverage containers. Exposure of animal and cell models to doses of BPA below the recommended tolerable daily intake (TDI) of 50 μg/kg/day have been shown to alter specific estrogen-responsive gene expression, but this has not previously been shown in humans
Gravitational waves from single neutron stars: an advanced detector era survey
With the doors beginning to swing open on the new gravitational wave
astronomy, this review provides an up-to-date survey of the most important
physical mechanisms that could lead to emission of potentially detectable
gravitational radiation from isolated and accreting neutron stars. In
particular we discuss the gravitational wave-driven instability and
asteroseismology formalism of the f- and r-modes, the different ways that a
neutron star could form and sustain a non-axisymmetric quadrupolar "mountain"
deformation, the excitation of oscillations during magnetar flares and the
possible gravitational wave signature of pulsar glitches. We focus on progress
made in the recent years in each topic, make a fresh assessment of the
gravitational wave detectability of each mechanism and, finally, highlight key
problems and desiderata for future work.Comment: 39 pages, 12 figures, 2 tables. Chapter of the book "Physics and
Astrophysics of Neutron Stars", NewCompStar COST Action 1304. Minor
corrections to match published versio
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