371 research outputs found
Antioxidants in peripheral arterial disease
No full textPeripheral arterial disease (PAD) is an important manifestation of systemic atherosclerosis that is characterized by obstruction of the arteries in the lower limbs. Experimental and epidemiological studies suggested a key role for oxidative stress in initiation and progression of the atherosclerotic process. The results of these studies provided a good basis for interventional trials with antioxidants, particularly with vitamin E, but the findings were conflicting. In this paper we review the observational and interventional studies with antioxidants, and ask whether vitamins supplementation should or should be not be recommended for PAD patients
"Pelvic ultrasound evaluation in transgender male during testosterone therapy" G. Senofonte, E. Marcoccia, C. Boccherini, M. Marasco, A. Perlorca, G. Nigro, A. Giancotti, M. Mosconi, F. Lombardo
No full textIntroduction: Gender dysphoria (GD) is characterised by significant distress and/or poor
social functioning due to a non-congruence between an individual’s assigned gender and the
perceived gender identity. In Female to Male subjects, androgen therapy aims to induce
physical changes (such as hair growth, tone voice decrease, fat mass redistribution, breast
volume reduction, etc) and cessation of menses. The latest guidelines (Hembree, 2017)
suggest a higher risk of malignancies (uterus and ovaries) and of endometrial hyperplasia than
cis-gender female, secondary to testosterone therapy. Therefore, a radical
hysteroannesisectomy is recommended after 2 years of therapy.
Aims: The aim of this study is the acquisition of data from pelvic ultrasound surveillance in
Transgender Male in order to evaluate endometrial thickness, uterine and ovarian volume.
Materials and Methods: FtM subjects referred to the outpatient clinic of Endocrinology and
Andrology of the Department of Experimental Medicine, “Sapienza” University of Rome, for
Gender Dysphoria, sent by their mental health specialists. We recruited 26 patients (mean age
27.3 ± 11.0) with the following inclusions criteria: diagnosis of gender dysphoria, participation
on follow-up, no previous testosterone therapy; exclusions criteria were: history of
gynaecological surgery/hysterectomy, menopause. Each patient underwent clinical
evaluation, blood testosterone test and US evaluation before starting therapy (T0) and after
six months of therapy (T 6). The hormone therapy consisted of intramuscolar testosterone
undecanoate 250 mg-every 28 days.
Results: Twenty-six subjects underwent the baseline evaluation: mean uterine volume was
49.4 ± 21.7 cc, mean endometrial thickness was 5.0 ± 3.5 mm, mean right ovarian volume was
5.9 ± 5.3 cc, mean left ovarian volume was 7.5 ± 6.8 cc and mean endometrial thickness was
5.0 ± 3.5 mm. At this time, 12 patients finished six months therapy and returned for control.
The cessation of menses occurred in all patients after a median of 2 months (approximately 2
testosterone undecanoate injections). There was no significant difference in post therapy
mean uterine volume (49.4 ± 21.7 cc vs 49.9 ± 29.0 cc, T0 vs T6, p = 0.43) and in endometrial
thickness (5.0 ± 3.5 mm vs 2.7 ± 1.0 mm, T0 vs T6, p = 0.15). Instead we detected a significant
decrease in mean left ovarian volume (7.5 ± 6.8 cc vs 2.7 ± 1.1, T0 vs T6, p = 0.002) and right
ovarian volume (5.9 ± 5.3 cc vs 2.3 ± 1.7, T0 vs T6, p =0.010). Blood tests confirmed a
significant increase of testosterone levels after six months of therapy (1.3 ± 0.9 vs 13.4 ± 4.5
nnmol/L, T0 vs T6; p=0.001). We did not detect any significant correlation between
testosterone levels under treatment and ovarian volume.
Conclusions: Testosterone therapy induces marked physical changes, as demonstrated by
menses cessation and reduction of ovarian volume, although apparently not correlated with
mean blood testosterone level. No significant difference were found in endometrial thickness
and uterine volume, though these results may be due in part to the small number of enrolled
subjects. Future increase of study cohort and longer follow up will strengthen our results and
possibly provide information on risk of malignancies in trangender males
Search for flavour-changing neutral-current top quark decays to c-quark and Z boson using the Atlas detector at the LHC
No full textThe main focus of this thesis is the search for the t → Zc process in the proton–proton collisions data collected by the ATLAS detector at the Large Hadron Collider located at CERN. The flavour-changing neutral-current (FCNC) processes are forbidden at tree-level and highly suppressed at loop-level which is why they are very rare phenomena in the Standard Model of particle physics. However, this processes have a higher probability to occur in several theories beyond the Standard Model where the suppression could be relaxed and the loop diagrams mediated by new bosons could contribute. The FCNC top-quark decays t → Zc are searched in tt pair events with one top quark decaying through the t → Zc channel and the other through the dominant Standard Model mode t → Wb. The analysed data were recorded at a center-of-mass energy of 13 TeV and correspond to the full Run-2 dataset with an integrated luminosity of 139 fb−1 . The data are consistent with Standard Model background contributions, and, at 95% confidence level the search sets observed (expected) upper limits of 11.8 × 10−5 (9.5 × 10−5 ) on the t → cZ branching ratio, constituting the most stringent limit to date and improving the previous ATLAS results by a factor of 2 (2.5)
Should antioxidant status be considered in interventional trials with antioxidants?
No full textThe last decade has seen many trials with antioxidants in patients with cardiovascular disease, with equivocal results. One possible explanation for the disappointing findings is the lack of identification criteria of patients who are potential candidates for antioxidant treatment. Several studies have been carried out in parents at risk of cardiovascular disease, indicating that enhanced oxidative stress is associated with the presence of diabetes, hypercholesterolaemia, hypertension, and smoking. This review analyses the data reported so far to determine whether they clearly support the premise that patients at risk of cardiovascular events may be candidates for antioxidant treatment
The Concept of Early Systemic Sclerosis Following 2013 ACR\EULAR Criteria for the Classification of Systemic Sclerosis.
No full textSignal analysis in gravitational wave data
No full textIn this thesis, I study the gravitational wave signals coming from compact objects on both present-stage, and future gravitational wave detectors.
The thesis is based on 3 articles, which will be presented after two brief introductory chapters, aimed to guide the reader through some of the main concepts and tools required in the analysis of the presented papers.
In the first article we adopt the Pearson Cross-Correlation analysis, to perform an agnostic search on real detector data of the first four LIGO gravitational wave detections. This work was motivated as a follow-up to some studies carried out by a group at the Niels-Bohr Institute. In their works, they tried to reproduce the detections claimed by the LIGO collaboration using matched filtering, and they discovered that the waveforms used by the LIGO collaboration in their subtractions were not optimal, as some of the signal remained buried in the detector noise after the subtraction. In the paper we used different waveforms, obtained through maximum-likelihood, and we demonstrate that the residual signal found in the noise was just a consequence of the choice of waveforms. Such signal, buried in the residual detector noise, is hence not a result of mismatching on the model but can be removed by using a more accurate waveform description. Furthermore, we show that the LIGO results can be reproduced with statistical significance even by using the Pearson cross-correlation method, even though with this approach the statistical significance will be slightly lower compared to the results obtained using matched filtering.
For the second article we moved to the case of simulated signals, coming from many events, on a future space-based detector datastream. To this extent we analyze the Stochastic Gravitational Wave Background predicted on the LISA detector, which is given by the superposition of all the weak unresolvable signals on the detector strain. We forecast the signal on the LISA detector strain by using the results coming from the latest LVK population inference paper, and produced catalogs representing a Stellar-Origin Black Hole population in our Universe. The Stochastic Gravitational Wave Background is then computed by adopting four different methods, that in order of complexity, range from a simple analytical evaluation to estimating the real detector strain after synthesizing a black hole population and iteratively subtracting all the resolvable sources. We find that, when the assumed SNR threshold is high enough to keep the number of resolvable sources small (∼ 10 over 4 years of observation), all the methods give results well in agreement with each other. This implies that, when working with LISA data, it is possible to use the fast analytical estimation for the stochastic noise component with a small loss of precision. On the other hand, the use of more complex methods like the iterative subtraction of a synthesized population, despite naturally requiring numerical cuts in the population generation phase due to its computational cost, can present both the value of the Stochastic Gravitational Wave Background amplitude as well as the resolvable sources predicted on the LISA strain at the same time. It can hence be useful when both these quantities need to be taken into account in a particular study.
We conclude on the third article by studying the synergy of multiple future gravitational wave detectors (both Earth-based and Space-based), in assessing the presence of secondary population channels in the detectors data stream. To this extent, we investigate the prospects of identifying potential Primordial Black Hole Binary populations over the astrophysical Stellar-Origin Black Hole Binary population of our Universe. We once again assume that our fiducial population follows the latest LVK GWTC-3 inference paper results, and we forecast our analysis on the next generation of gravitational wave detectors. We consider different possibilities both for the merger rate and mass function of the studied Primordial Black Hole subpopulations, and we perform our analysis by focusing on the signatures at higher redshifts than the current LVK detection horizon. We exploit the fact that the astrophysical black holes of our universe are supposed to follow a distribution as a function of redshift closely related to the Star Formation Rate, which is supposed to peak and then slowly die off. At distances beyond the peak of the stellar formation rate, the Stellar-Origin Binary Black Hole contribution will hence become negligible, whereas Primordial Black Hole models predict many sources and will dominate. We generally find that Earth-based and space-based detectors work synergistically, and the value of the Stochastic Gravitational Wave Background measured by LISA will generally be able to improve constraining the presence of additional sub-populations compared to the case when only Earth-based detector observations are considered
Current Status on Canine Foetal Fluid and Adnexa Derived Mesenchymal Stem Cells
No full textEffective standards of care treatment guidelines have been developed for many canine diseases. However, a subpopulation of patients is partially or completely refractory to these protocols, so their owners seek novel therapies such as treatments with MSCs. Although in dogs, as with human medicine, the most studied MSCs sources have been bone marrow and adipose tissue, in recent years, many researchers have drawn attention towards alternative sources, such as foetal adnexa and fluid, since they possess many advantages over bone marrow and adipose tissue. Foetal adnexa and fluid could be considered as discarded material; therefore, sampling is non-invasive, inexpensive and free from ethical considerations. Furthermore, MSCs derived from foetal adnexa and fluid preserve some of the characteristics of the primitive embryonic layers from which they originate and seem to present immune-modulatory properties that make them a good candidate for allo- and xenotransplantation. The aim of the present review is to offer an update on the state of the art on canine MSCs derived from foetal adnexa and fluid focusing on the findings in their clinical settin
The role of calcium carbonate in the geomechanical behaviour of Pliocene lacustrine deposits.
No full textThe results of a study on the influence of calcium carbonate content on the physical characteristics and compressibility parameters of Pliocene lacustrine deposits are discussed. The origin of CaCO3 has been investigated and it is thought to have been precipitated, after consolidation, as cement which partially filled the void spaces between soil particles. Average CaCO3 content was about 22% along a 116.5 m deep vertical profile. The CaCO3 in the clay and silt fractions (CaCO3*) was considered the best available estimate of that acting as cement. The relationships reported in the literature between Atterberg limits and CaCO3 content have been statistically confirmed by the tests performed on decalcified laboratory samples, but not by those performed on natural samples due to lithological heterogeneities. Yield stress, constrained modulus, swelling index and microstructure resistance were affected by CaCO3* content in the stress range lower than yield stress. In the stress range higher than sigma'(vy), no relationship was observed between C-c and CaCO3, while an inverse relationship between C-s and CaCO, was observed in both the natural and remoulded samples and thus is thought to be due to the presence of inactive calcite. Moreover, the remoulded samples also show an increase in C-s with respect to the natural ones. From these findings it follows that the yield stress for cemented materials corresponds to the partial disruption of the structure
Weathering of Valle Ricca stiff and jointed clay
No full textThe study proposes a weathering model of Pliocene-Pleistocene stiff and jointed blue-grey clay transforming into yellow clay. Physical, mineralogical, chemical and textural changes, as well as the weathering profile were investigated in a quarry of central Italy. Based on geological records and inferences, these changes are likely to have occurred within a time-span of about 50,000 years BP, upon overburden stress unloading and in a stress regime that is locally controlled by suction. Weathering propagated into the clay at a rate of about 0.3 mm/year and was enhanced by the enlargement of the pre-existing tectonic discontinuities and by the fori-nation of new joints. A mass loss of about 22-25 wt.% was calculated. Considering Fe and P as immobile elements, the individual oxides contribute to mass loss in the following order: SiO2 > CaO = CO2 > Al2O3 > MgO > K2O > S > Na2O > TiO2 > MnO. The Fe2O3/(Fe2O3+FeO) ratio varies from 9-29% in the blue-grey clay to 75-82% in the yellow one. Oxidation and/or dissolution of 7 angstrom-Fe2+-bearing clay minerals, mica-like minerals and calcite and parallel increase of smectite and Fe-hydroxides play a critical role in the chemical changes and explain the higher plasticity of the yellow clay with respect to the blue-grey one. The role of water during the weathering process was inferred to occur in cyclical steps: 1) seepage of meteoric water; 2) dissemination of highly oxidizing meteoric water; 3) triggering of oxidation and dissolution of minerals; 4) water evaporation; 5) partial migration of the elements contained in the aqueous solution and consequent deposition of minerals in the joints. (C) 2005 Elsevier B.V. All rights reserved
BlaB-15, a new BlaB metallo-β-lactamase variant found in an Elizabethkingia miricola clinical isolate
No full textA multidrug-resistant strain of Elizabethkingia miricola was isolated from the urine of a 2-year-old boy hospitalized for severe clinical conditions. The strain produces 2 metallo-β-lactamases belonging to subclasses B1 and B3: a new BlaB variant (BlaB-15) and a GOB-7–like enzyme
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