212 research outputs found
Laryngeal mask perforation: complication of jugular vein cannulation in a newborn
This case report describes the perforation of a laryngeal mask during central venous cannulation of the internal jugular vein in a 2000 g, formerly preterm infant. The procedure was undertaken with the patient under general anaesthesia with a laryngeal mask and spontaneous breathing. As a result of the infant's clinical status, multiple needle insertions were required to obtain venous access. The needle was inadvertently advanced to the retropharynx and perforated the air-filled part of the laryngeal mask. Ventilation parameters remained stable. The laryngeal mask causes anatomical alterations of cervical structures in the newborn and therefore its use for the airway management during jugular vein cannulation appears to be limite
The SPOrt Project: Cosmological and Astrophysical Goals
We present the cosmological and astrophysical objectives of the SPOrt
mission, which is scheduled for flying on the International Space Station (ISS)
in the year 2002 with the purpose of measuring the diffuse sky polarized
radiation in the microwave region. We discuss the problem of disentangling the
cosmic background polarized signal from the Galactic foregrounds.Comment: 10 pages; 5 PS figures; requires aipproc2.cls, aipproc2.sty,
epsfc.tex; to appear in Proc. of ``3K Cosmology'', Rome 5-10 Oct. 199
The Coaxial L-P Cryogenic Receiver of the Sardinia Radio Telescope
The design and characterization of the coaxial dual-band L-P radio astronomical receiver for the prime focus of the Sardinia radio telescope are presented. The main feature of this receiver is to allow simultaneous radio astronomical observations in the P (305-410 MHz) and L (1.3-1.8 GHz) frequency bands. This functionality, which has been requested by the Pulsar research group at the National Institute for Astrophysics to estimate, among the others, the ionospheric dispersion in Pulsar observation, is currently missing in any other radio astronomical facility throughout the world. Also, single band operation is ensured by the proposed design both in linear and circular polarization, making this L-P receiver an ideal instrument for a wide range of radio astronomical and space applications. Some components of the receiver chain have been housed inside a cryostat and refrigerated at 20 K to reduce the noise temperature, resulting in a good performance compared to the receivers of other large radio telescopes. Several challenging issues have been faced in the design, mainly due to the large dimension and weight of the overall structure to be mounted in the prime focus position. Moreover, the design of the cryostat was constrained by the limited space available in the direction of the optical axis inside the focal cabin of the radio telescope, requiring a compact and light realization of the components of the receiver chain. This called for a home-made design of several devices, requiring a strong collaborative effort by researchers, engineers, and astronomers
Autologous Microfragmented Adipose Tissue Reduces the Catabolic and Fibrosis Response in an in Vitro Model of Tendon Cell Inflammation
Background. Mesenchymal stem cells (MSCs) emerged as a promising therapy for tendon pathologies. Microfragmented adipose tissue (\u3bcFAT) represents a convenient autologous product for the application of MSC-based therapies in the clinical setting. In the present study, the ability of \u3bcFAT to counteract inflammatory processes induced by IL-1\u3b2 on human tendon cells (TCs) was evaluated. Methods. Cell viability and proliferation were evaluated after 48 hours of transwell coculture of TCs and autologous \u3bcFAT in the presence or absence of IL-1\u3b2. Gene expression of scleraxis, collagen type I and type III, metalloproteinases-1 and -3, and cyclooxygenase-2 was evaluated by real-time RT-PCR. The content of VEGF, IL-1Ra, TNF\u3b1, and IL-6 was evaluated by ELISA. Results. IL-1\u3b2-treated TCs showed augmented collagen type III, metalloproteases, and cyclooxygenase-2 expression. \u3bcFAT was able to reduce the expression of collagen type III and metalloproteases-1 in a significant manner, and at the same time, it enhanced the production of VEGF, IL-1Ra, and IL-6. Conclusions. In this in vitro model of tendon cell inflammation, the paracrine action of \u3bcFAT, exerted by anti-inflammatory molecules and growth factors, was able to inhibit the expression of fibrosis and catabolic markers. Then, these results suggest that the application of \u3bcFAT may represent an effective conservative or adjuvant therapy for the treatment of tendon disorders
A project for polarimetric observations in single dish with Medicina and Noto 32 m antennas
A project with multidisciplinary characteristics, aimed to implement the possibility of polarimetric measurements in single dish at the VLBI stations of Medicina and Noto, is presented. The project will open a new window on many
astrophysical items that may be approached using the already existing instrumentation and facilities of the two Italian radioastronomical stations. We report here some scientific backgrounds, together with some technical evaluations, on which the feasibility of the project is based
Mirna reference genes in extracellular vesicles released from amniotic membrane-derived mesenchymal stromal cells
Human amniotic membrane and amniotic membrane-derived mesenchymal stromal cells (hAMSCs) have produced promising results in regenerative medicine, especially for the treatment of inflammatory-based diseases and for different injuries including those in the orthopedic field such as tendon disorders. hAMSCs have been proposed to exert their anti-inflammatory and healing potential via secreted factors, both free and conveyed within extracellular vesicles (EVs). In particular, EV miRNAs are considered privileged players due to their impact on target cells and tissues, and their future use as therapeutic molecules is being intensely investigated. In this view, EV-miRNA quantification in either research or future clinical products has emerged as a crucial paradigm, although, to date, largely unsolved due to lack of reliable reference genes (RGs). In this study, a panel of thirteen putative miRNA RGs (let-7a-5p, miR-16-5p, miR-22-5p, miR-23a-3p, miR-26a-5p, miR-29a-5p, miR-101-3p, miR-103a-3p, miR-221-3p, miR-423-5p, miR-425-5p, miR-660-5p and U6 snRNA) that were identified in different EV types was assessed in hAMSC-EVs. A validated experimental pipeline was followed, sifting the output of four largely accepted algorithms for RG prediction (geNorm, NormFinder, BestKeeper and \u394Ct method). Out of nine RGs constitutively expressed across all EV isolates, miR-101-3p and miR-22-5p resulted in the most stable RGs, whereas miR-423-5p and U6 snRNA performed poorly. miR-22-5p was also previously reported to be a reliable RG in adipose-derived MSC-EVs, suggesting its suitability across samples isolated from different MSC types. Further, to shed light on the impact of incorrect RG choice, the level of five tendon-related miRNAs (miR-29a-3p, miR-135a-5p, miR-146a-5p, miR-337-3p, let-7d-5p) was compared among hAMSC-EVs isolates. The use of miR-423-5p and U6 snRNA did not allow a correct quantification of miRNA incorporation in EVs, leading to less accurate fingerprinting and, if used for potency prediction, misleading indication of the most appropriate clinical batch. These results emphasize the crucial importance of RG choice for EV-miRNAs in hAMSCs studies and contribute to the identification of reliable RGs such as miR-101-3p and miR-22-5p to be validated in other MSC-EVs related fields
Radio monitoring of a sample of X- and gamma-ray loud blazars
In this paper we present the results of a 4-year (1996 - 1999) radio flux
density monitoring program for a sample of X- and -ray loud blazars.
Our program started in January 1996 and was carried out on monthly basis at the
frequencies of 5 GHz and 8.4 GHz with the 32-m antennas located in Medicina
(Bologna, Italy) and Noto (Siracusa, Italy). 22 GHz data collected in Medicina
from January 1996 to June 1997 will also be presented. The sample of selected
sources comprises most radio loud blazars with
characterised by emission in the X- and -ray regimes, and target
sources for the BeppoSAX X-ray mission. All sources in the sample, except
J1653+397 (MKN 501), are variable during the four years of our monitoring
program. We classified the type of variability in each source by means of a
structure function analysis. We also computed th for all
epochs with nearly simultaneous observations ate spectral index and found that
starts flattening at the very beginning o f a radio flare,
or flux density increase.Comment: 12 pages, 3 tables and 1 figure, in press on A&
Low energy high angular resolution neutral atom detection by means of micro-shuttering techniques: the BepiColombo SERENA/ELENA sensor
The neutral sensor ELENA (Emitted Low-Energy Neutral Atoms) for the ESA
cornerstone BepiColombo mission to Mercury (in the SERENA instrument package)
is a new kind of low energetic neutral atoms instrument, mostly devoted to
sputtering emission from planetary surfaces, from E ~20 eV up to E~5 keV,
within 1-D (2x76 deg). ELENA is a Time-of-Flight (TOF) system, based on
oscillating shutter (operated at frequencies up to a 100 kHz) and mechanical
gratings: the incoming neutral particles directly impinge upon the entrance
with a definite timing (START) and arrive to a STOP detector after a flight
path. After a brief dissertation on the achievable scientific objectives, this
paper describes the instrument, with the new design techniques approached for
the neutral particles identification and the nano-techniques used for designing
and manufacturing the nano-structure shuttering core of the ELENA sensor. The
expected count-rates, based on the Hermean environment features, are shortly
presented and discussed. Such design technologies could be fruitfully exported
to different applications for planetary exploration.Comment: 11 page
Full Stokes polarimetric observations with a single-dish radio-telescope
The study of the linear and circular polarization in AGN allows one to gain
detailed information about the properties of the magnetic fields in these
objects. However, especially the observation of circular polarization (CP) with
single-dish radio-telescopes is usually difficult because of the weak signals
to be expected. Normally CP is derived as the (small) difference of two large
numbers (LHC and RHC); hence an accurate calibration is absolutely necessary.
Our aim is to improve the calibration accuracy to include the Stokes parameter
V in the common single-dish polarimetric measurements, allowing a full Stokes
study of the source under examination. A detailed study, up to the 2nd order,
of the Mueller matrix elements in terms of cross-talk components allows us to
reach the accuracy necessary to study circular polarization. The new
calibration method has been applied to data taken at the 100-m Effelsberg
radio-telescope during regular test observations of extragalactic sources at
2.8, 3.6, 6 and 11 cm. The D-terms in phase and amplitude appear very stable
with time and the few known values of circular polarization have been
confirmed. It is shown that, whenever a classical receiver and a multiplying
polarimeter are available, the proposed calibration scheme allows one to
include Stokes V in standard single-dish polarimetric observations as
difference of two native circular outputs.Comment: 10 pages, to be published in A&
High Levels of Circulating Type II Collagen Degradation Marker (CTx-II) Are Associated with Specific VDR Polymorphisms in Patients with Adult Vertebral Osteochondrosis
Both vitamin D and collagen have roles in osteocartilaginous homeostasis. We evaluated the association between the circulating 25-hydroxyvitamin D (25(OH)D) type I and II collagen degradation products (CTx-I, and CTx-II), and four vitamin D receptor gene (VDR) polymorphisms, in Italian males affected by low back pain (LBP) due to herniation/discopathy and/or vertebral osteochondrosis. FokI, BsmI, ApaI, and TaqI VDR-polymorphisms were detected through PCR-restriction fragment length polymorphism (RFLP), and circulating 25(OH)D, CTx-I and CTx-II were measured by immunoassays in 79 patients (of which 26 had osteochondrosis) and 79 age-, sex- and body mass index (BMI)-matched healthy controls. Among all 158 subjects, carriers of FF and Ff genotypes showed lower 25(OH)D than ff, which suggested a higher depletion of vitamin D in F allele carriers. Higher CTx-I concentrations were observed in TT versus Tt among controls, and Tt versus tt among LBP cases, which suggested a higher bone-cartilaginous catabolism in subjects bearing the T allele. Higher CTx-II concentrations were observed in patients with osteochondrosis bearing FF, bb, TT, or Aa genotypes in comparison with hernia/discopathy patients and healthy controls. Vertebral osteochondrosis shows peculiar genotypic and biochemical features related to vitamin D and the osteocartilaginous metabolism. Vitamin D has roles in the pathophysiology of osteochondrosis
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