Bisphosphonates are compounds that inhibit bone reabsorption mediated by osteoclasts. The use of bisphosphonates in oral implantology is still in the experimental stage. The aim of this study is to ...evaluate the efficacy of an aminobisphosphonate to increase the ability of the drug to act on the implant and bone surfaces in the development of the osseointegration in sheep. Forty SLA titanium implants were used on sheep iliac crests. Neridronate added to connective gel (test 1) or to physiological solution (test 2) was used in order to increase the bone and implant adhesiveness. Physiological solution (control 1) or connective gel (control 2) alone was given to the control groups. A topical administration of Neridronate was made on the implant surface and in the implant site. Four Bergamasca sheep were used and were sacrificed by intravenous injection of 10 cc Tanax after 8 weeks from implantation. Histologic and histomorphometric analyses were carried out. The results did not show significant differences between the test group and control group. Our data are different from other similar studies obtaining statistically significant differences. These differences could depend on the procedure of application of the drug on the implant. This study demonstrates the poor efficacy of neridronate applied topically to the implant and implant site during surgery. Further studies using different fixation techniques of the drug may be necessary to confirm the present data.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Abstract
Background
Angiography-Based Vessel FFR (vFFR) demonstrated a strong correlation with invasive fractional flow reserve (FFR) in both a pre- and post-percutaneous coronary intervention (PCI) ...setting. However, the role of vFFR and its correlation with post-PCI FFR in chronic coronary occlusion (CTO) has not been evaluated yet. We sought to investigate the diagnostic performance of post-PCI vFFR with post-PCI FFR as a reference in patients undergoing successful CTO PCI.
Methods
Between March 2016 and September 2019, a total of 80 patients from the FFR-SEARCH and FFR REACT studies underwent successful CTO recanalization 1,2). A total of 50 patients (median age 66 (IQR: 56–74) years, 76% were male) were eligible for the analysis. Median FFR was 0.89 (IQR: 0.84–0.94) while median vFFR was 0.91 (IQR: 0.85–0.94). Suboptimal physiological results, defined as FFR and vFFR <0.90, were identified in 26 (52%) and in 21 (42%) patients, respectively. A strong correlation (r=0.79) was found between vFFR and FFR with a mean bias of 0.013±0.051. Receiver-operating characteristics curve analysis revealed an excellent accuracy of vFFR in predicting FFR <0.90 (AUC: 0.97; 95% CI: 0.93–1.00).
Conclusion
vFFR shows a good agreement with FFR and a high diagnostic accuracy for FFR ≤0.90 in patients undergoing successful PCI of a CTO lesion.
Funding Acknowledgement
Type of funding sources: None.
Pleomorphic adenoma or mixed tumour (MT) is a benign neoplasia of slow growth and epithelial histogenesis. We report a particular case of recurring MT of the hard palate. A 39-year-old man came to us ...with a swelling of the hard half-palate. The patient, 19 years earlier, had had a small formation in the same place that, over a period of three years had slowly grown. Histology showed that it was an MT and it was promptly removed. Sixteen years after the operation, a small recurrence reappeared, reaching a diameter of 12 mm. The patient underwent a new excision. The case reported is of particular interest due to many aspects: the outbreak from the minor salivary glands; the male sex; the young age of the patient at the first sign of the tumour; the appearance of a recurrence after 16 years, not contemplated in literature; and finally, the rapid growth of the second appearance.
Abstract
Background
Coronary, thoracic aorta and aortic valve calcium can be measured from a non-gated chest computer tomography (CT) and are validated predictors of cardiovascular events and ...all-cause mortality. However, their prognostic role in acute systemic inflammatory diseases, such as COVID-19, has not been investigated.
Purpose
The principal aim was to evaluate the association of coronary artery calcium (CAC) and total thoracic calcium on in-hospital mortality in COVID-19 patients. Then, to evaluate the prognostic impact of clinical and subclinical coronary artery disease (CAD), as assessed by CAC.
Methods
1093 consecutive patients from 16 Italian hospitals with a positive swab for COVID-19 and an admission chest CT for pneumonia severity assessment were included in the SCORE COVID-19 registry (calcium score for COVID-19 Risk Evaluation). At CT, coronary, aortic valve and thoracic aorta calcium were qualitatively and quantitatively evaluated separately and combined together (total thoracic calcium) by a central Core-lab blinded to patients' outcomes. A specific sub analysis on CAC was performed stratifying the patients in three groups: (a) “clinical CAD” (prior revascularization history), (b) “subclinical CAD” (CAC >0), (c) “No CAD” (CAC=0). In-hospital mortality was the primary endpoint, while a composite of myocardial infarction and cerebrovascular accident (MI/CVA) was the secondary one.
Results
Non-survivors compared to survivors had higher coronary artery (487.7±565.3 vs 207.7±406.8, p<0.001), aortic valve (322.4±390.9 vs 98.2±250.7 mm2, p<0.001) and thoracic aorta (3786.7±4225.5 vs 1487.6±2973.1 mm2, p<0.001) calcium values. Coronary artery calcium (HR 1.308; 95% CI, 1.046 - 1.637, p=0.019) and total thoracic calcium (HR 1.975; 95% CI, 1.200 - 3.251, p=0.007) resulted to be independent predictors of in-hospital mortality. In the sub - analysis increasing rates of in-hospital mortality (11.3% vs. 27.3% vs. 39.8%, p<0.001) and MI/CVA events (2.3% vs. 3.8% vs. 11.9%, p<0.001) were observed from the No CAD to the clinical CAD groups. Among patients with subclinical CAD, increasing CAC burden was associated with higher rates of in-hospital mortality (20.5% vs. 27.9% vs. 38.7% for patients with CAC score thresholds ≤100, 101–400 and >400, respectively, p<0.001)
Conclusion
Coronary, aortic valve and thoracic aortic calcium assessment on admission non-gated CT permits to stratify the COVID-19 patients in-hospital mortality risk. Cardiovascular calcifications may represent a bystander of an impaired vascular reserve, both microvascular and endothelial, but also a sign of vascular senescence. Therefore, it can be considered an index of biological frailty, likely more accurate than age and other risk factors.
Funding Acknowledgement
Type of funding sources: None. Figure 1Figure 2
Abstract
Introduction
Recent studies demonstrated a strong relation between suboptimal post-PCI fractional flow reserve (FFR) and clinical outcome. The feasibility of post-PCI FFR optimization and ...its impact on future clinical outcome remains topic of debate.
Purpose
The aim of the present substudy of the FFR REACT trial was to identify predictors of 1) absolute FFR increase following optimization and 2) successful functional optimization (final FFR ≥0.90).
Methods
The FFR REACT trial was a single-center, investigator initiated, randomized controlled trial including patients with (un)stable angina or non-ST segment elevation myocardial infarction and angiographically successful PCI. Following a post-PCI FFR <0.90, patients were randomized to intravascular ultrasound (IVUS)-guided optimization according to a dedicated optimization protocol (intervention arm) or no further treatment (control arm). In case of PCI optimization, FFR and IVUS were repeated to evaluate the optimization result. The present analysis included all patients randomized to IVUS-guided optimization, who actually underwent PCI optimization, and who had pre- and post-optimization FFR values available. We performed multivariate linear and logistic regression models to identify predictors of absolute FFR increase and FFR ≥0.90 following optimization.
Results
A total of 145 patients were allocated to the IVUS-guided optimization arm with 152 vessels having a post-PCI FFR <0.90 (mean post-PCI FFR: 0.83±0.05), of which 104 vessels (68.4%) underwent additional treatment after IVUS evaluation. Paired FFR measurements (pre- and post-optimization) were available in 100/104 optimized vessels. The mean absolute change in FFR was 0.03±0.06 (p<0.001), and 20/100 (20%) vessels achieved a final FFR ≥0.90.
Both left anterior descending arteries (LAD) (mean change = -0.033, 95%CI -0.055- -0.010, p=0.004) and higher post-PCI FFR values (mean change per 0.01 unit increase = -0.005, 95%CI -0.007 - -0.004, p<0.001) were associated with lower changes in FFR following optimization.
Independent predictors of achieving a final FFR ≥0.90 were higher post-PCI FFR values (OR 1.26 per 0.01 unit increase, 95%CI 1.06-1.51, p=0.009) and non-LAD vessels (OR 5.72, 95%CI 1.73-18.94, p=0.004).
Conclusions
Within the FFR REACT trial, we observed that the likelihood of improvement in final FFR values was driven by the initial post-PCI FFR values (before optimization) and the location of the target vessel, with non-LAD lesion location being a significant predictor of FFR increase.
The roughness and the purity of implant surfaces are key points in the osteointegration process. The surfaces obtained by classic methods present irregular non-reproducible patterns and furthermore ...contaminate the implant surface with materials other than titanium which interfere with the process of osteointegration. The aim of the present study is to evaluate, by SEM/EDX and XPS analyses, the surface microstructure and the purity of new laser-treated implant surfaces. The laser treatment of the surface allows to set parameters to determine the roughness in order to obtain a regular and repeatable surface. Furthermore, there being no contact between the implant and the machine, there is no surface contamination with elements other than titanium. In this study we used a diode-pumped solid state laser (DPSS) with Nd:YAG source operating in Q-Switching mode on titanium samples. The resulting samples were analysed by SEM/EDX and XPS to evaluate morphology and purity of the surface. The results show surfaces with very regular roughness and a total absence of contamination.
We present a stochastic algorithm to solve numerically the problem of finding the global minimizers of a real valued function subject to lower and upper bounds. This algorithm looks for the global ...minimizers following the paths of a suitable system of stochastic differential equations. Numerical experience on several test problems known in literature is shown.
Direct and inverse acoustic scattering problems involving smart obstacles are proposed and some ideas to study them are suggested. A smart obstacle is an obstacle that when hit by an incoming ...acoustic wave reacts circulating on its boundary a pressure current, that is a quantity dimensionally given by a pressure divided by a time, in order to generate a scattered wave that pursues a preassigned goal. In our models (see 6–10,12) the smart obstacle pursues one of the following goals: i) to be undetectable, ii) to appear with a shape and/or acoustic boundary impedance different from its actual ones, iii) to appear with a shape and/or acoustic boundary impedance and in a location in space different from its actual ones. That is, in the first case the smart obstacle tries to be furtive, in the second case it tries to be masked that is it tries to appear as another obstacle that we call the mask and finally in the third case it tries to appear as another obstacle in a location in space different from its actual one. We refer to this last apparent obstacle as the ghost. The direct scattering problem considered is the following: given the incoming acoustic field, the obstacle, its acoustic impedance and its goal formulate an adequate mathematical model for the problems previously considered and find the optimal strategy to pursue the assigned goal within the proposed model. The inverse scattering problem considered is the following: given the knowledge of several far fields generated by the smart obstacle when hit by known incident acoustic fields it reacts with the optimal strategy and the knowledge of the goal pursued by the obstacle find the obstacle (i.e. find the shape, acoustic impedance and spatial location of the obstacle). For simplicity in this paper we limit our attention to the case of the obstacle that tries to be masked when the incoming acoustic field is time harmonic. Moreover in the inverse problem we assume that the acoustic boundary impedance of the obstacle and of the mask are known. In this case the direct scattering problem is translated in a constrained optimization problem and its solution is characterized as the solution of a set of auxiliary equations. The inverse scattering problem is translated in a two steps optimization procedure. Finally in a test case the inverse problem is solved numerically.
We consider a bounded obstacle characterized by a boundary electromagnetic impedance contained in the three dimensional real Euclidean space filled with a homogeneous isotropic medium. When an ...incoming electromagnetic field illuminates the obstacle a scattered field is generated. A smart obstacle is an obstacle that in the scattering process, circulating a surface electric current density on its boundary, tries to achieve a given goal. We consider four possible goals: making the obstacle undetectable (i.e.: furtivity problem), making the obstacle to appear with a shape and impedance different from its actual ones (i.e.: masking problem), making the obstacle to appear in a location different from its actual one eventually with a shape and impedance different from its actual ones (i.e.: ghost obstacle problem) and finally one of the previous goals limited to a given subset of the frequency space (i.e.: definite band problems). We consider the problem of determining the optimal electric current density to achieve the given goal. The relevance in many application fields (i.e. stealth technology, electromagnetic noise control, etc.) of these problems is well known. The previous problems are modelled as optimal control problems for the Maxwell equations. Some numerical results on test problems obtained solving the optimal control problems proposed are shown.
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