7,643 research outputs found
The influence of a new clinical motion for endodontic instruments on the incidence of postoperative pain
Previous studies showed that motor motions play an important role in determining apical extrusion of debris. Therefore a new clinical motion (MIMERACI) has been proposed. The basic idea is to progress slowly (1mm advancement), and after each 1mm, to remove the instrument from the canal, clean flutes and irrigate. The aim of the study was to prove whether the clinical use of MIMERACI technique would influence or not postoperative pain.MATERIALS AND METHODS:
100 teeth requesting endodontic treatment were selected for the study and divided into two similar groups based on anatomy, pre-operative symptoms and vitality, presence or absence of periapical lesion. All teeth were shaped, cleaned and obturated by the same operator, using the same NiTi instruments. The only difference between the two groups was the instrumentation technique: tradional (group A) vs MIMERACI (group B). Assessment of postoperative pain was performed 3 days after treatment. Presence, absence and degree of pain were recorded with a visual analogue scale (VAS), validated in previous studies. Collected data statistically analyzed using one-way ANOVA post hoc Tukey test.
RESULTS:
For VAS pain scores MIMERACI technique showed significantly better results than group A (p=0,031). Overall, both incidence and intensity of symptoms were significantly lower. Flare ups occurred in 3 patients, but none treated with the MIMERACI Technique.
CONCLUSIONS:
Since extruded debris can elicit more postoperative pain, results obtained by using MIMERACI technique are probably due to many factors: better mechanical removal and less production of debris and more efficient irrigation during instrumentation
Controlled surface initiated polymerization of N-isopropylacrylamide from polycaprolactone substrates for regulating cell attachment and detachment
Poly(ε-caprolactone) (PCL) substrates were modified with thermoresponsive poly(N-isopropylacrylamide) (PNIPAM) brushes to direct and control cellular attachment and detachment. Prior to brush growth, the surface of PCL was activated by a diamine to allow for initiator coupling. Infrared spectra taken before and after cell culturing demonstrated the covalently attached nature of the PNIPAM brushes. PCL is a biocompatible polymer and to prove that the modifications described above did not change this characteristic property, a cell attachment/detachment study was carried out. The modified substrates showed a lower cell attachment when compared to PCL alone and to PCL films modified with the initiator. The possibility to detach the cells in the form of a sheet was proved using PNIPAM-modified PCL films by lowering the temperature to 25 °C. No relevant detachment was shown by the unmodified or by the initiator modified surfaces. This confirmed that the detachment was temperature dependent and not connected to other factors such as polymer swelling. These functionalized polymeric films can find applications as smart cell culture systems in regenerative medicine applications
Relaxation of spherical systems with long-range interactions: a numerical investigation
The process of relaxation of a system of particles interacting with
long-range forces is relevant to many areas of Physics. For obvious reasons, in
Stellar Dynamics much attention has been paid to the case of 1/r^2 force law.
However, recently the interest in alternative gravities emerged, and
significant differences with respect to Newtonian gravity have been found in
relaxation phenomena. Here we begin to explore this matter further, by using a
numerical model of spherical shells interacting with an 1/r^alpha force law
obeying the superposition principle. We find that the virialization and
phase-mixing times depend on the exponent alpha, with small values of alpha
corresponding to longer relaxation times, similarly to what happens when
comparing for N-body simulations in classical gravity and in Modified Newtonian
Dynamics.Comment: 6 pages, 3 figures, accepted in the International Journal of
Bifurcation and Chao
Public reporting on individual hospitals’ quality: the risk of misinformation
Obiettivo: benché con sempre maggiore frequenza i mass media riportino informazioni sulla qualità dei servizi, spesso con
l’esplicito intento di individuare i «migliori», la comunicazione di questi temi avviene attraverso modalitĂ che o sono troppo semplicistiche nel loro sforzo di confrontare le performance cliniche dei singoli centri, o ricorrono a indicatori di qualitĂ
inadeguati. In tale senso, queste informazioni possono facilmente portare a interpretazioni errate. Questo lavoro considera due esempi concreti per evidenziare il problema.
Metodi: sono stati utilizzati due casi recenti di comunicazione
attraverso i mass media delle performance cliniche di centri cardiochirurgici: i risultati dello studio BPAC «Esiti a breve termine di interventi di by-pass coronarico nelle cardiochirurgie
italiane», coordinato dall’ISS, e la pubblicazione sulla rivista
Panorama di quelle che erano definite come le migliori cardiochirurgie italiane sulla base di un indice di reputazione.
Risultati: il primo dei casi citati evidenzia i problemi della rappresentazione delle performance con semplici league tables. Con
un metodo basato su Markov Chain Monte Carlo si evince che
il ricorso alle classifiche, pur basate su un corretto indicatore di
esito, è un esercizio potenzialmente fuorviante. Nel secondo caso, si dimostra l’inaffidabilità di un indice reputazionale utilizzato come indicatore della qualità dei servizi.
Conclusione: le modalità con cui si comunica al pubblico la qualità dei servizi sono ancora largamente inadeguate e quindi potenzialmente fuorvianti nell’indirizzare le scelte dei cittadini
Prevalence and pharmacologic management of familial hypercholesterolemia in an unselected contemporary cohort of patients with stable coronary artery disease
INTRODUCTION:
Familial hypercholesterolemia (FH) is an inherited disorder characterized by elevated plasma levels of low-density lipoprotein cholesterol (LDL-C) associated with premature cardiovascular disease.
METHODS:
Using the data from the START (STable Coronary Artery Diseases RegisTry) study, a nationwide, prospective survey on patients with stable coronary artery disease (CAD), we described prevalence and lipid lowering strategies commonly employed in these patients. The study population was divided into "definite/probable FH," defined as a Dutch Lipid Clinic Network (DLCN) score ≥6, "possible FH" with DLCN 3-5, and "unlikely FH" in presence of a DLCN <3.
RESULTS:
Among the 4030 patients with the DLCN score available, 132 (3.3%) were classified as FH (2.3% with definite/probable and 1.0% with possible FH) and 3898 (96.7%) had unlikely FH. Patients with both definite/probable and possible FH were younger compared to patients not presenting FH. Mean on-treatment LDL-C levels were 107.8 ± 41.5, 84.4 ± 40.9, and 85.8 ± 32.3 (P < 0.0001) and a target of ≤70 mg/dL was reached in 10.9%, 30.0%, and 22.0% (P < 0.0001) of patents with definite/probable, possible FH, and unlikely FH, respectively. Statin therapy was prescribed in 85 (92.4%) patients with definite/probable FH, in 38 (95.0%) with possible FH, and in 3621 (92.9%) with unlikely FH (P = 0.86). The association of statin and ezetimibe, in absence of other lipid-lowering therapy, was more frequently used in patients with definite/probable FH compared to patients without FH (31.5% vs 17.5% vs 9.5%; P < 0.0001).
CONCLUSIONS:
In this large cohort of consecutive patients with stable CAD, FH was highly prevalent and generally undertreated with lipid lowering therapies
Rotational arherectomy in the distal left anterior descending coronary artery through an internal mammary artery graft.
We report the case of a 53-year-old white man who began complaining of dyspnoea and angina 19 months after coronary artery bypass graft surgery. Coronary angiography revealed the presence of a long and critical stenosis in the native left anterior descending coronary artery, shortly after distal anastomosis of the left internal mammary artery. After failed predilatations with standard or cutting balloons, we successfully used the rotablator system, which allowed us to implant a bare-metal stent in the native left anterior descending coronary artery. However, stent deployment caused long linear graft dissection, which was reduced by drug-eluting stent implantation in the proximal and distal segments of the left internal mammary artery
The possible prognostic role of histone deacetylase and transforming growth factor β/Smad signaling in high grade gliomas treated by radio-chemotherapy: a preliminary immunohistochemical study
Glioblastoma (GBM) is the most common and aggressive tumor of the central nervous system. Unfortunately, patients affected by this disease have a very poor prognosis, due to high level of invasiveness and resistance to standard therapies. Although the molecular profile of GBM has been extensively investigated, the events responsible for its pathogenesis and progression remain largely unknown. Histone Deacetylases (HDAC) dependent epigenetic modifications and transforming growth factor (TGF)-β/Smad pathway seem to play an important role in GBM tumorigenesis, resistance to common therapies and poor clinical outcome. The aim of this study was to evaluate the involvement and the possible interaction between these two molecular cascades in the pathogenesis and prognosis of GBM. Immunohistochemistry (IHC) was performed on microdissected GBM samples, collected from 14 patients (6 men and 8 women) ranging in age from 43 to 74 years. The patients were previously divided, on the basis of their overall survival (OS), into two groups: short and long OS. Patients with poor prognosis showed hyperexpression of HDAC4 and HDAC6, an activation of the TGF-β/Smad pathway, with high levels of IL-13, Smad2, PDGF and MMP3 expression, compared to the long survivors. The short OS group exhibits a decrease in Smad 7 expression and also low levels of p21 immunostaining, which represents a common target of the two pathways. The IHC data was confirmed by quantitative analysis and Immunoblotting. Our preliminary results suggest that both HDAC4 and HDAC6 together with the TGF-β/Smad pathway may be involved in progression of GBM and this cross talking could be a useful prognostic marker in this deadly disease
On the vacuum of the minimal nonsupersymmetric SO(10) unification
We study a class of nonsupersymmetric SO(10) grand unified scenarios where
the first stage of the symmetry breaking is driven by the vacuum expectation
values of the 45-dimensional adjoint representation. Three decade old results
claim that such a Higgs setting may lead exclusively to the flipped SU(5) x
U(1) intermediate stage. We show that this conclusion is actually an artifact
of the tree level potential. The study of the accidental global symmetries
emerging in various limits of the scalar potential offers a simple
understanding of the tree level result and a rationale for the drastic impact
of quantum corrections. We scrutinize in detail the simplest and paradigmatic
case of the 45_{H} + 16_{H} Higgs sector triggering the breaking of SO(10) to
the standard electroweak model. We show that the minimization of the one-loop
effective potential allows for intermediate SU(4)_C x SU(2)_L x U(1)_R and
SU(3)_c x SU(2)_L x SU(2)_R x U(1)_{B-L} symmetric stages as well. These are
the options favoured by gauge unification. Our results, that apply whenever the
SO(10) breaking is triggered by , open the path for hunting the simplest
realistic scenario of nonsupersymmetric SO(10) grand unification.Comment: 22 pages, 1 figure. Refs added. To appear in Phys. Rev.
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