23 research outputs found
Spectroscopic monitoring of the candidate tidal disruption event in F01004-2237
We present results of spectroscopic monitoring observations of the
Ultra-Luminous Infra Red Galaxy F01004-2237. This galaxy was observed to
undergo changes in its optical spectrum, detected by comparing a spectrum from
2015 with one from 2000. These changes were coincident with photometric
brightening. The main changes detected in the optical spectrum are enhanced He
II 4686 emission and the appearance of He I
3898,5876 emission lines. The favoured interpretation of
these changes was that of a tidal disruption event (TDE) happening in 2010.
However, subsequent work suggested that these changes are caused by another
hitherto unknown reason related to variations in the accretion rate in the
active galactic nucleus (AGN). Our optical spectroscopic monitoring
observations show that the evolution of the He lines is in line with the
evolution seen in TDEs and opposite of what observed from reverberation mapping
studies of AGNs, renewing the discussion on the interpretation of the flare as
a TDE.Comment: 9 pages, 3 figures, 2 tables. Accepted for publication on ApJ on
January 22, 202
Intraoperative imaging O-Arm™ in secondary surgical correction of post-traumatic orbital fractures
Abstract Purpose To determine the safety and efficacy of O-Arm™ intraoperative imaging in maxillofacial surgery of post-traumatic orbital fractures. In order to ensure correct placement of titanium plate, immediately after fixing, viewable, in the axial, sagittal and coronal images. Methods The authors evaluated 5 consecutive adult patients with orbital fractures who required a reoperation involving displacement of titanium mesh between January and December 2015. The displacement or incorrect positioning of titanium mesh was detected at post-operative CT scan or clinical neurological findings. Intraoperative O-Arm™ imaging was used for our patients who underwent secondary maxillofacial orbital fracture surgery due to the failure of first surgical approach. Results An eyelid incision was performed in order to obtain maximal exposure and minimizing cosmetic defects. Any previous fixation device was skeletonized and removed, any improperly reduced fracture was mobilized, reduced and refixated with 1.5 mm plates, screws and titanium mesh. The intra-operative O-Arm™ imaging technique was used at the end of the procedures. In 4 cases it confirmed the appropriateness of the newly obtained reconstruction, in 1 case a first scan showed a suboptimal result and the devices were correctly repositioned, guided by the O-Arm™ images. Conclusions Intraoperative O-Arm™ assisted craniofacial reconstruction surgery improves the assessment of neurovascular structure decompression, skeletal fragment identification, fixation procedures and for the correct re-establishment of facial symmetry in orbital floor fractures
Interleukin (IL)-22 receptor 1 is over-expressed in primary Sjogren's syndrome and Sjögren-associated non-Hodgkin lymphomas and is regulated by IL-18.
The aim of this study was to elucidate more clearly the role of interleukin (IL)-18 in modulating the IL-22 pathway in primary Sjögren's syndrome (pSS) patients and in pSS-associated lymphomas. Minor salivary glands (MSGs) from patients with pSS and non-specific chronic sialoadenitis (nSCS), parotid glands biopsies from non-Hodgkin lymphomas (NHL) developed in pSS patients, were evaluated for IL-18, IL-22, IL-22 receptor 1 (IL-22R1), IL-22 binding protein (IL-22BP) and signal transducer and activator of transcription-3 (STAT-3) expression. MSGs IL-22R1-expressing cells were characterized by confocal microscopy and flow cytometry in pSS, nSCS and healthy controls . The effect of recombinant IL-18 and IL-22 on peripheral blood mononuclear cells (PBMCs) from pSS and nSCS was studied by flow cytometry and reverse transcription-polymerase chain reaction (RT-PCR). MSGs of pSS and NHL were characterized by an imbalance between IL-22 and IL-22BP protein expression, with IL-18 and IL-22BP being expressed in a mutually exclusive manner and IL-18 and IL-22R1 being correlated directly. Aberrant expression of IL-22R1, induced by IL-18, was observed only among tissue and circulating myeloid cells of pSS patients and macrophages of NHL tissues of pSS patients, but not nSCS. IL-22R1 expression on PBMC of pSS was functional, as its stimulation with recombinant IL-22 significantly up-regulated the expression of STAT-3, IL-17 and IL-22. An IL-18-dependent aberrant expression of IL-22R1 on cells of haematopoietic origin seems to be a specific immunological signature of patients with pSS and pSS-associated lymphomas
The spectral evolution of AT 2018dyb and the presence of metal lines in tidal disruption events
We present light curves and spectra of the tidal disruption event (TDE)
ASASSN-18pg / AT 2018dyb spanning a period of one year. The event shows a
plethora of strong emission lines, including the Balmer series, He II, He I and
metal lines of O III 3760 and N III 4100, 4640
(blended with He II). The latter lines are consistent with originating from the
Bowen fluorescence mechanism. By analyzing literature spectra of past events,
we conclude that these lines are common in TDEs. The spectral diversity of
optical TDEs is thus larger than previously thought and includes N-rich events
besides H- and He-rich events. We study how the spectral lines evolve with
time, by means of their width, relative strength, and velocity offsets. The
velocity width of the lines starts at 13000 km s and decreases
with time. The ratio of He II to N III increases with time. The same is true
for ASASSN-14li, which has a very similar spectrum to AT 2018dyb but its lines
are narrower by a factor of 2. We estimate a black hole mass of
= by using the -
relation. This is consistent with the black hole mass derived using the MOSFiT
transient fitting code. The detection of strong Bowen lines in the optical
spectrum is an indirect proof for extreme ultraviolet and (reprocessed) X-ray
radiation and favors an accretion origin for the TDE optical luminosity. A
model where photons escape after multiple scatterings through a super-Eddington
thick disk and its optically thick wind, viewed at an angle close to the disk
plane, is consistent with the observations.Comment: Accepted version. Updated with new photometry and spectra, including
an X-shooter spectrum used to determine the BH mass. Two more figures added
and line measurements tabulated. No significant scientific updates and the
conclusions remain unaffecte
Clinical features and outcomes of elderly hospitalised patients with chronic obstructive pulmonary disease, heart failure or both
Background and objective: Chronic obstructive pulmonary disease (COPD) and heart failure (HF) mutually increase the risk of being present in the same patient, especially if older. Whether or not this coexistence may be associated with a worse prognosis is debated. Therefore, employing data derived from the REPOSI register, we evaluated the clinical features and outcomes in a population of elderly patients admitted to internal medicine wards and having COPD, HF or COPD + HF. Methods: We measured socio-demographic and anthropometric characteristics, severity and prevalence of comorbidities, clinical and laboratory features during hospitalization, mood disorders, functional independence, drug prescriptions and discharge destination. The primary study outcome was the risk of death. Results: We considered 2,343 elderly hospitalized patients (median age 81 years), of whom 1,154 (49%) had COPD, 813 (35%) HF, and 376 (16%) COPD + HF. Patients with COPD + HF had different characteristics than those with COPD or HF, such as a higher prevalence of previous hospitalizations, comorbidities (especially chronic kidney disease), higher respiratory rate at admission and number of prescribed drugs. Patients with COPD + HF (hazard ratio HR 1.74, 95% confidence intervals CI 1.16-2.61) and patients with dementia (HR 1.75, 95% CI 1.06-2.90) had a higher risk of death at one year. The Kaplan-Meier curves showed a higher mortality risk in the group of patients with COPD + HF for all causes (p = 0.010), respiratory causes (p = 0.006), cardiovascular causes (p = 0.046) and respiratory plus cardiovascular causes (p = 0.009). Conclusion: In this real-life cohort of hospitalized elderly patients, the coexistence of COPD and HF significantly worsened prognosis at one year. This finding may help to better define the care needs of this population
Initial characterization of interstellar comet 2I/Borisov
Interstellar comets penetrating through the Solar System had been anticipated
for decades. The discovery of asteroidal-looking 'Oumuamua was thus a huge
surprise and a puzzle. Furthermore, the physical properties of the 'first
scout' turned out to be impossible to reconcile with Solar System objects,
challenging our view of interstellar minor bodies. Here, we report the
identification and early characterization of a new interstellar object, which
has an evidently cometary appearance. The body was discovered by Gennady
Borisov on 30 August 2019 UT and subsequently identified as hyperbolic by our
data mining code in publicly available astrometric data. The initial orbital
solution implies a very high hyperbolic excess speed of ~32 km/s, consistent
with 'Oumuamua and theoretical predictions. Images taken on 10 and 13 September
2019 UT with the William Herschel Telescope and Gemini North Telescope show an
extended coma and a faint, broad tail. We measure a slightly reddish colour
with a g'-r' colour index of 0.66 +/- 0.01 mag, compatible with Solar System
comets. The observed morphology is also unremarkable and best explained by dust
with a power-law size-distribution index of -3.7 +/- 1.8 and a low ejection
speed (44 +/- 14 m/s for = 1 particles, where is the ratio of
the solar gravitational attraction to the solar radiation pressure). The
nucleus is probably ~1 km in radius, again a common value among Solar System
comets, and has a negligible chance of experiencing rotational disruption.
Based on these early characteristics, and putting its hyperbolic orbit aside,
2I/Borisov appears indistinguishable from the native Solar System comets.Comment: Published in Nature Astronomy on 14 October 201
Antitumor activity of water extract of pleurotus species growing on root residues against colon cancer cells
In vitro antitumor effects of the cold-water extracts of Pleurotus eryngii var ferulae and Pleurotus nebrodensis on human colon cancer cells
For centuries, mushrooms have been used as folk medicines especially in Asian countries where their medicinal properties are well known. On the basis of numerous experimental evidences collected in the last decades, the immunomodulatory and anti-neoplastic properties of substances extracted from various species belonging to genera of edible mushrooms [Agaricus L., Auricularia Bull. ex Juss., Ganoderma P. Karst., Grifola Gray, Lentinus Fr., Schizophyllum Fr., Tremella Dill ex L., etc.] are extensively recognized also at scientific levels. Several works have demonstrate that anti-cancer property of these molecules is due to their ability to enhance immune system activity and/or to act directly on cancer cells. Polysaccharides are responsible of a remarkable antitumor activity in vivo and many authors demonstrated their action through screening against sarcoma 180 in mice with an intraperitoneal or oral methods of administration (Ikekawa et al., 1969; Mori et al., 1986; Mizuno et al., 1995, Wasser & Weis, 1997).
Among the well-studied medicinal mushrooms there are those belonging to the genus Pleurotus (Fr.) P. Kumm., one of the widely cultivated edible mushroom. Most of them are cultivated and provide a relatively cheap food of high dietetic value through rather simple solid-state fermentation processes. In addition, Pleurotus biomass demonstrates significant medicinal effects and its bioactive compounds possess antibiotic, antitumor, hypocholesterolemic and immunomodulation properties (Gunde-Cimerman, 1999; Babitskatya et al., 2000; Gunde-Cimerman & Plemenitas, 2001; Wasser, 2002; Zhang et al., 2004; Chang, 2006; Tsai et al., 2009). Most of researches concerning the anti-tumor properties of Pleurotus spp. have been carried out by testing the methanol/ethanol/ hot water extracts of Pleurotus ostreatus (Jacq.) P. Kumm. in several in vivo and in vitro cancer models. These studies provided interesting data supporting the possibility to isolate new therapeutic agents from this mushroom, but much less is known about the biological activities of extracts from other species of genus Pleurotus.
Species like P. eryngii (DC.) Quél. var. ferulae (Lanzi) Sacc. and P. nebrodensis (Inzenga) Quél. are typical Mediterranean mushrooms and are particularly popular as choice edible mushrooms (Gargano et al., 2011 Zervakis, 2001).
The aim of the present research was to evaluate whether the cold-water extract of P. eryngii var. ferulae (CWE-Pef) and P. nebrodensis (CWE-Pn) can affect the tumor phenotype of human colon cancer cells. Our result demonstrate that CWE-Pef and CWE-Pn inhibited the growth of HCT116 colon cancer cells by inducing apoptosis, promoted cancer cells aggregation and inhibited the adhesion of tumor cells to endothelial cells. Furthermore, both extracts inhibited tyrosine phosphorylation signaling as well as ERK phosphorylation. These effects were specific for tumor cells since no effects were observed on non-tumor cells. Finally, our data indicated that the active compounds may be protein/peptide compounds since high temperature treatment of CWE-Pef and CWE-Pn completely eliminated their anti-proliferative activity