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This study aimed at evaluating volumetrically gaps and voids of calcium-silicate based materials of different generations and handling properties (BC—Endosequence BC RRM-Fast Set Condensable Putty, MTA—ProRoot MTA, and BIO—Biodentine) in simulated furcal perforations in an ex vivo setup by microcomputed tomography (Micro-CT) analysis. Thirty-six extracted human mandibular molars with sound furcation areas were selected. Standardized perforations were created in the furcation area of the pulp chamber using #4 diamond burs. The specimens were randomly assigned to three groups (BC, MTA and BIO; n = 12). Samples were then scanned (SkyScan 1172; Bruker-microCT, Kontich, Belgium), and three-dimensional (3D) images reconstructed. The relative volume of gaps (VG%) and voids (VV%) present on each material was calculated. Data were analyzed using one-way analysis of variance (ANOVA) and Tukey’s HSD test (p < 0.05). Mean VG% for BC, MTA, and BIO groups were, respectively, 0.513%, 1.128%, 1.460%, with BC presenting statistically (p < 0.05) fewer gaps formation than the other groups. Mean VV% were, respectively, 0.018%, 0.037%, and 0.065%. The was no statistical difference regarding VV%. There were no gap-free and void-free samples. BC group had the lowest VG% among the groups with a significant statistical difference (p < 0.05).

This study aimed at evaluating the volume of gaps and voids, and the total porosity percentage of three calcium-silicate-based materials in mandibular molars apicoectomy by Micro-CT analysis. Thirty-three mesial roots of extracted human mandibular molars were instrumented and obturated. The apical 3mm of each root was resected and prepared. Root-end cavities were filled with EndoSequence BC Putty (BC); ProRoot MTA (MTA) and Biodentine (BIO). Samples were scanned using a Micro-CT scanner and the tridimensional images reconstructed. Percentage of gaps (VG%) and of voids (VV%) were obtained. Porosity percentage (Po%) was also assessed. Data were analysed using Student's t-test (P < 0.05). All materials presented gaps and voids. VG% was 2.006 (BC), 1.882 (MTA) and 1.450 (BIO), and VV% was 0.039 (BC), 0.021 (MTA) and 0.024 (BIO) with no statistical difference. Po% were 56.73 (BC), 51.94 (MTA) and 50.45 (BIO), with BC being statistically (P > 0.05) more porous., (© 2020 Australian Society of Endodontology Inc.)

Introduction: The maintenance of a stem cell pool is imperative to enable healing processes in the dental pulp tissue throughout life. As such, knowing mechanisms underlying stem cell self-renewal is critical to understand pulp pathophysiology and pulp regeneration. The purpose of this study was to evaluate the impact of stem cell factor (SCF) signaling through its receptor tyrosine kinase (c-Kit) on the self-renewal of human dental pulp stem cells (hDPSCs)., Methods: The hDPSCs were stably transduced with lentiviral vectors expressing shRNA-c-Kit or vector control. The impact of the SCF/c-Kit axis on hDPSC self-renewal was evaluated by using a pulpsphere assay in low attachment conditions and by evaluating the expression of polycomb complex protein Bmi-1 (master regulator of self-renewal) by Western blot and flow cytometry., Results: The c-Kit-silenced hDPSCs formed fewer pulpspheres when compared with hDPSCs transduced with control vector (P < .05). Evaluation of pulpsphere morphology revealed the presence of 3 distinct sphere types, ie, holospheres, merospheres, and paraspheres. Although c-Kit silencing decreased the number of holospheres compared with control cells (P < .05), it had no effect on the number of merospheres and paraspheres. Recombinant human stem cell factor (rhSCF) increased the number of holospheres (P < .05) and induced dose-dependent Bmi-1 expression in hDPSCs. As expected, the inductive capacity of rhSCF on Bmi-1 expression and fraction of Bmi-1-positive cells was inhibited when we silenced c-Kit in hDPSCs., Conclusions: These results unveiled the role of SCF/c-Kit signaling on the self-renewal of hDPSCs and suggested that this pathway enables long-term maintenance of stem cell pools in human dental pulps., (Copyright © 2020 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.)

Objectives: To assess the viability of dental pulp stem cells loaded with gold nanoparticles complexed with poly (L-lysine) (AuNP-PLL) and to track the cellular behavior in a 3D analysis by micro-CT., Materials and Methods: DPSC (dental pulp stem cells) were cultured and incorporated with AuNP-PLL (0.2 mg/ml) and assessed for cell viability (24 h, 48 h, and 72 h) using MTS assay. Apoptosis/cell death index and cell cycle were analyzed by propidium iodide. AuNP-PLL-RITC were used for observation in confocal microscopy and quantification of the incorporation rates. Cells were also suspended in agarose and analyzed three-dimensionally in μCT, assessing their radiopacity. Quantitative data (cell viability and apoptosis) were analyzed by t test (p < 0.05)., Results: AuNP-PLL labeling did not affect cellular viability in any of the periods analyzed nor interfered with the apoptosis index of DPSC. AuNP-PLL nanocomplexes were identified in the cytoplasm of cells by immunofluorescence, mainly in the perinuclear region. The observed incorporation rate was 98%. Micro-CT analysis has shown that incorporated cells are now visible using x-ray, with a clear increase in radiopacity when compared to the control group (non-incorporated cells)., Conclusion: These results indicate that it is possible to incorporate AuNP-PLL complex into DPSC and track the cells by using μCT; furthermore, this incorporation of 0.2 mg/ml of AuNP-PLL does not interfere in the DPSC basic behavior., Clinical Relevance: This methodology can be a useful tool for cellular labeling to observe cell behavior and their interaction with scaffolds in a 3D manner, opening an array of new approaches in regenerative endodontics.

Aim: Pulmonary artery diastolic pressure (PADP) correlates closely with pulmonary wedge pressure (PAWP); therefore, we sought to evaluate whether an algorithm based on PADP assessment by the Doppler pulmonary regurgitation (PR) end-diastolic gradient (PRG) may aid in estimating increased PAWP in cardiac patients with reduced or preserved left ventricular (LV) ejection fraction (EF)., Methods and Results: Right heart catheterization, with estimation of PAWP, right atrial pressure (RAP), PADP, and Doppler echocardiography, was carried out in 183 patients with coronary artery disease (n = 63), dilated cardiomyopathy (n = 52), or aortic stenosis (n = 68). One-hundred and seventeen patients had LV EF <50%. We measured the pressure gradients across the tricuspid and pulmonary valves from tricuspid regurgitation (TRV) and PR velocities. Doppler-estimated PADP (e-PADP) was obtained by adding the estimated RAP to PRG. An algorithm based on e-PADP to predict PAWP, that included TRV, left atrial volume index, and mitral E/A, was developed and validated in derivation (n = 90) and validation (n = 93) subgroups. Both invasive PADP (r = .92, P < .001) and e-PADP (r = .72, P < .001) correlated closely with PAWP, and e-PADP predicted PAWP (AUC: 0.85, CI: 0.79-0.91) with a 94% positive predictive value (PPV) and a 55% negative predictive value (NPV), after exclusion of five patients with precapillary pulmonary hypertension. The e-PADP-based algorithm predicted PAWP with higher accuracy (PPV = 94%; NPV = 67%; accuracy = 85%; kappa: 0.65, P < .001) than the ASE-EACVI 2016 recommendations (PPV = 97%; NPV = 47%; accuracy = 68% undetermined = 18.9%; kappa: 0.15, P < .001)., Conclusions: An algorithm based on noninvasively e-PADP can accurately predict increased PAWP in patients with cardiac disease and reduced or preserved LV EF., (© 2020 Wiley Periodicals, Inc.)

The aim of this study was to evaluate the effects of Wnt signaling through lipoprotein receptor-related protein 6 (LRP6) and Frizzled6 on the endothelial differentiation of dental pulp stem cells (DPSCs). DPSCs were stably transduced with enhanced green fluorescent protein (EGFP)-tagged lentiviral vectors (short hairpin RNA-LRP6, short hairpin RNA-Frizzled6, or empty vector controls). We evaluated the effects of LRP6 and Frizzled6 on expression of endothelial markers and on capillary tube formation mediated by DPSCs induced with recombinant human Wnt1 (rhWnt1) and/or recombinant human vascular endothelial growth factor 165 (rhVEGF 165 ). In vivo, tooth slices/scaffolds were seeded with LRP6-silenced, Frizzled6-silenced, or vector control DPSC cells and transplanted into immunodeficient mice. The density of blood vessels generated by DPSCs differentiated into vascular endothelial cells was analyzed by immunohistochemistry for EGFP. The rhWnt1 and rhVEGF 165 induced expression of active β-catenin in control DPSCs and in Frizzled6-silenced DPSCs, but not in LRP6-silenced DPSCs. Furthermore, VEGF and interleukin-8 were downregulated in LRP6-silenced DPSCs, but not in control DPSCs or in Frizzled6-silenced DPSCs (P < .05). Likewise, rhWnt1 and rhVEGF 165 induced expression of the endothelial marker VEGF receptor-2 in control DPSCs and in Frizzled6-silenced DPSCs, but not in LRP6-silenced DPSCs. These data correlated with a trend for lower density of capillary sprouts generated by LRP6-silenced DPSCs when compared with control DPSCs in Matrigel. In vivo, tooth slice/scaffolds seeded with DPSC-short hairpinRNA-LRP6 cells showed lower density of human blood vessels (ie, EGFP-positive blood vessels), when compared with tooth slice/scaffolds seeded with vector control cells (P < .05). Collectively, these data demonstrated that LRP6 signaling is necessary for the vasculogenic differentiation of human DPSCs., (Copyright © 2017 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.)

Vasculogenesis is the process of de novo blood vessel formation observed primarily during embryonic development. Emerging evidence suggest that postnatal mesenchymal stem cells are capable of recapitulating vasculogenesis when these cells are engaged in tissue regeneration. However, the mechanisms underlining the vasculogenic differentiation of mesenchymal stem cells remain unclear. Here, we used stem cells from human permanent teeth (dental pulp stem cells [DPSC]) or deciduous teeth (stem cells from human exfoliated deciduous teeth [SHED]) as models of postnatal primary human mesenchymal stem cells to understand mechanisms regulating their vasculogenic fate. GFP-tagged mesenchymal stem cells seeded in human tooth slice/scaffolds and transplanted into immunodeficient mice differentiate into human blood vessels that anastomize with the mouse vasculature. In vitro, vascular endothelial growth factor (VEGF) induced the vasculogenic differentiation of DPSC and SHED via potent activation of Wnt/β-catenin signaling. Further, activation of Wnt signaling is sufficient to induce the vasculogenic differentiation of postnatal mesenchymal stem cells, while Wnt inhibition blocked this process. Notably, β-catenin-silenced DPSC no longer differentiate into endothelial cells in vitro, and showed impaired vasculogenesis in vivo. Collectively, these data demonstrate that VEGF signaling through the canonical Wnt/β-catenin pathway defines the vasculogenic fate of postnatal mesenchymal stem cells. Stem Cells 2016;34:1576-1587., (© 2016 AlphaMed Press.)

Introduction: This study aimed to investigate the correlation and the agreement between periapical radiography (PR) and cone-beam computed tomography (CBCT) correlating to histologic findings in the diagnosis of apical periodontitis (AP)., Methods: One hundred thirty-four premolar root canals from 10 dogs were treated after AP induction. Four months later, the animals were killed, and standard digital PRs were obtained. The area of AP was measured by using ImageJ software. CBCT (i-CAT) images from each arch were obtained, and AP area and volume were measured by using Osiri-X software. The apical inflammatory infiltrate was evaluated under light microscopy. The correlation between imaging methods was evaluated by using the Pearson coefficient. The Bland-Altman method was used to assess the agreement between PR and CBCT data. The Spearman coefficient was used to correlate the imaging data and histologic findings., Results: Despite a strong correlation between PR and CBCT areas, the agreement limits were very broad (95% limits of agreement, 0.19-1.08). PR only measured, on average, 63% of CBCT values. Although there was a strong correlation between PR area and CBCT volume, the Bland-Altman method suggests that the larger the CBCT volume, the more underestimated the PR value. When APs had a volume smaller than 6 mm(3), the PR estimation of CBCT data was unpredictable. A positive correlation was found for PR area, CBCT area, CBCT volume, and histology data., Conclusions: The diagnosis of AP based on PR data is clinically limited, and it should not be used for scientific investigations., (Copyright © 2014 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.)

Aim: Periradicular surgery is a procedure that includes surgical exposure of the diseased apex, root-end cavity preparation, and retrofilling of the root canal. The aim of this study was to compare the outcomes of periradicular surgery in vitro using different dental materials and storage methods for human teeth specimens., Methods: The sample comprised 60 human single-rooted teeth, divided into two groups according to mode of storage (hydrated or non-hydrated); each group was then subdivided by retrofilling material (mineral trioxide aggregate or resin-modified glass ionomer cement). Each specimen was analyzed by digital radiography and scanning electron microscopy (SEM). Quantitative assessment of the gap between the retrofilling material and dentin surface was conducted by observation of apical views (2000x magnification) of four areas of each specimen., Results: The gap between retrofilling material and the internal dentin surface of the root was found to be significantly wider in hydrated teeth (P=0.002). Comparison of the two retrofilling materials showed that, regardless of tooth storage method, use of glass ionomer cement was associated with significantly wider gaps between the filling material and dentin surface (P=0.001). Comparisons of tooth storage mode versus retrofilling material showed a statistical interaction (P=0.009) between these factors., Conclusion: Mineral trioxide aggregate (MTA®) provided the best apical sealing, regardless of storage medium. Resin-modified glass ionomer cement (Vitremer®) was associated with substantially larger mean gap values when used in hydrated teeth.

Background: Diabetes mellitus (DM) represents by itself a major risk factor for cardiovascular events and the coexistence of obesity with consequent left ventricular volumetric overload could be responsible for further damages on left ventricular function. Aim of this study was to demonstrate the effect of body mass index (BMI) on left ventricular function in diabetes patients with no cardiovascular complications and with normal ejection fraction (EF)., Materials and Methods: We evaluated 71 stable asymptomatic diabetes patients in optimal medical treatment and 24 healthy controls (C) (45% females; mean age: 58.4 +/- 9.4 years; BMI: 23.5 +/- 1.5). We stratified diabetes patients into two groups according to BMI: BMI <30 kg/m 2 (A: 44 patients; 47% females; mean age: 60.9 +/- 6.6 years; BMI: 25.7 +/- 1.9; Diabetes duration: 9.1 +/- 9.5 years); BMI >30 kg/m 2 (B: 27 patients; 37% females; mean age: 56.2 +/- 7.8 years; BMI: 33.0 +/- 2.1; Diabetes duration: 8.5 +/- 5.2 years). The following parameters were evaluated by conventional two dimensional (2D) echocardiography (GE VIVID 7) and tissue Doppler imaging (TDI): left ventricular dimensions (LVIDd; PWTd; IVSd), Left Ventricular Volumes (EDV, ESV), EF (by biplane Simpson's method), Left Ventricular Mass (by ASE formula), peak mitral annular velocity at septal and lateral levels (Sm and Sl). Global longitudinal strain (GLS) was obtained off line by Speckle tracking imaging method using Echopac 10 software., Results: Groups A, B were comparable for diabetes duration and glycated hemoglobin level, history of hypertension, and lipid profile. The EF was similar in the three groups, (A: 64 +/- 6%; B: 63 +/- 4%; C: 61 +/-5%; P = NS). LVMass 2.7 indexed for height was significantly higher in A and B in comparison with C (A: 45.2 +/- 8.1 g/m 2.7 ; B: 46.1 +/- 9.6 g/m 2.7 ; C: 39.5 +/- 4.9 g/m 2.7 ; P < 0.05). The stroke volume index (SVi) was significantly lower in B vs A (B: 35.3 +/- 5.7 ml/m 2 ; A: 39.3 +/7.1 ml/m 2 ; P = 0.033). GLS was significantly lower in group B respect A and C (C: 20.9 +/- 1.3%; A: -20.3+/-2.6%; B: -19 +/- 2; P < 0.05; P < 0.01)., Conclusions: In uncomplicated asymptomatic DM patients, the presence of first degree obesity plays an incremental role in adversely affecting left ventricular function and remodeling. The conventional echocardiographic methods such as the EF and the TDI are not so sensitive to identify the early LV dysfunction such as the evaluation of GLS by Speckle Tracking echocardiography. The longitudinal subendocardial fibers dysfunction in diabetes/obese patients could be derived by the complex interaction between metabolic (diabetes) and hemodynamic/endocrine abnormalities., Competing Interests: Conflict of Interest: None declared.

Objective: Obesity has reached global epidemic proportions and is associated with numerous comorbidities, including major cardiovascular (CV) diseases., Design and Methods: It has many adverse effects on hemodynamics and CV structure and function: it increases total blood volume and cardiac output, and the cardiac workload is greater. Typically, obese patients have a higher cardiac output but a lower level of total peripheral resistance at any given level of arterial pressure. Most of the increase in cardiac output in obesity is caused by stroke volume, although heart rate typically mildly increases also due to enhanced sympathetic activation., Results: Over the last few years, experimental investigations have unraveled some important pathogenetic mechanisms that may underlie a specific form of "obesity cardiomyopathy." Bariatric surgery represents an effective alternative to treat obesity when nonsurgical weight loss programs (diet + behavior modifications + regular exercise) have failed. A great numbers of questions are still open in the global comprehension of the pathophysiological interactions between obesity and heart., Conclusion: Conventional two-dimensional Doppler echocardiography, integrated by relative new technological ultrasonic approaches, represents the reference technique to study and possibly clarify both the very complex hemodynamic changes induced by obesity and those relative to obesity treatment., (Copyright © 2013 The Obesity Society.)

The recent development of transcatheter aortic valve implantation (TAVI) to treat severe aortic stenosis (AS) offers a viable option for high-risk patients categories. Our aim is to evaluate the early effects of implantation of CoreValve aortic valve prosthesis on arterial-ventricular coupling by two dimensional echocardiography. Sixty five patients with severe AS performed 2D conventional echocardiography before, immediately after TAVI, at discharge (mean age: 82.6 ± 5.9 years; female: 60%). The current third generation (18-F) CoreValve Revalving system (Medtronic, Minneapolis, MN) was used in all cases. Vascular access was obtained by percutaneous approach through the common femoral artery; the procedure was performed with the patient under local anesthesia. We calculated, apart the conventional parameters regarding left ventricular geometry and the Doppler parameters of aortic flow (valvular load), the vascular load and the global left ventricular hemodynamic load. After TAVI we showed, by echocardiography, an improvement of valvular load. In particular we observed an immediate reduction of transaortic peak pressure gradient (P < 0.0001), of mean pressure gradient (P < 0.0001) and a concomitant increase in aortic valve area (AVA) (0.97 ± 0.3 cm(2)). Left ventricular ejection fraction improved early after TAVI (before: 47 ± 11, after: 54 ± 11; P < .0001). Vascular load, expressed by systemic arterial compliance, showed a low but significant improvement after procedure (P < 0.01), while systemic vascular resistances showed a significant reduction after procedure (P < 0.001). As a global effect of the integrated changes of these hemodynamic parameters, we observed a significant improvement of global left ventricular hemodynamic load, in particular through a significant reduction of end-systolic meridional stress (before: 80 ± 34 and after: 55 ± 29, P < 0.0001). The arterial-valvular impedance showed a significant reduction (before: 7.6 ± 2 vs after: 5.8 ± 2; P < 0.0001. Furthermore we observed a significant reduction with a normalization of arterial-ventricular coupling (P < 0.005). With regard to left ventricular (LV) efficiency, we observed, after the procedure, a significant reduction of stroke work (P < 0.001) and potential energy (P < 0.001), with a significant increase of work efficiency early after the procedure (P < 0.001). Our results showed that the TAVI procedure was able to determine an early improvement of the global left ventricular hemodynamic load, allowing a better global LV performance. Further follow-up investigations are needed to evaluate these results in a more prolonged time observation.

Background: Surgical aortic valve replacement (SAVR) is the definitive proven therapy for patients with severe aortic stenosis who have symptoms or decreased left ventricular (LV) function. The development of transcatheter aortic valve implantation (TAVI) offers a viable and "less invasive" option for the treatment of patients with critical aortic stenosis at high risk with conventional approaches. The main objective of this study was the comparison of LV hemodynamic and structural modifications (reverse remodeling) between percutaneous and surgical approaches in the treatment of severe aortic stenosis., Methods: Fifty-eight patients who underwent TAVI with the CoreValve bioprosthetic valve were compared with 58 patients with similar characteristics who underwent SAVR. Doppler echocardiographic data were obtained before the intervention, at discharge, and after 6-month to 12-month follow-up., Results: Mean transprosthetic gradient at discharge was lower (P<.003) in the TAVI group (10±5 mm Hg) compared with the SAVR group (14±5 mm Hg) and was confirmed at follow-up (10±4 vs 13±4 mm Hg, respectively, P<.001). Paravalvular leaks were more frequent in the TAVI group (trivial to mild, 69%; moderate, 14%) than in the SAVR group (trivial to mild, 30%; moderate, 0%) (P<.0001). The incidence of severe prosthesis-patient mismatch (PPM) was significantly lower (P<.004) in the TAVI group (12%) compared with the SAVR group (36%). At follow-up, LV mass and LV mass indexed to height and to body surface area improved in both groups, with no significant difference. In patients with severe PPM, only the TAVI subgroup showed significant reductions in LV mass. LV ejection fraction improved at follow-up significantly only in TAVI patients compared with baseline values (from 50.2±9.6% to 54.8±7.3%, P<.0001)., Conclusions: Hemodynamic performance after TAVI was shown to be superior to that after SAVR in terms of transprosthetic gradient, LV ejection fraction, and the prevention of severe PPM, but with a higher incidence of aortic regurgitation. Furthermore, LV reverse remodeling was observed in all patients in the absence of PPM, while the same remodeling occurred only in the TAVI subgroup when severe PPM was present., (Copyright © 2011 American Society of Echocardiography. Published by Mosby, Inc. All rights reserved.)

Purpose: ST1481 is the lead compound of a novel series of 7-modified camptothecins, the 7-oxyimino methyl derivatives, characterized by potent topoisomerase I inhibition and cytotoxic activity. Based on its therapeutic efficacy in a human non-small cell lung carcinoma model and its favorable pharmacological profile, the novel analogue was selected for further preclinical development., Experimental Design: We investigated the growth-inhibitory effects of ST1481 and topotecan, used as a reference compound, in a panel of human tumor cell lines of various tumor types (ovarian carcinoma, glioblastoma, osteosarcoma, and melanoma), including sublines with acquired resistance to cisplatin. We explored the antitumor efficacy in a large panel of human tumor xenografts, with particular reference to intrinsically resistant tumor types, using oral administration and an intermittent treatment schedule., Results: ST1481 showed a potent antiproliferative activity with comparable effects in all tested cell lines. Only U-87-MG glioma cells were less sensitive, presumably as a consequence of the efficiency of the S-phase checkpoint. ST1481 produced a remarkable antitumor effect (tumor volume inhibition > 85%) in 16 of 18 examined models, with an appreciable rate of complete tumor regressions in 11 of 18 models (despite the nonoptimal intermittent treatment schedule). The most impressive antitumor effects were observed against lung carcinoma, melanoma, and osteosarcoma models, as documented by the high rate of complete responses (up to 100%). The efficacy of ST1481 was significantly superior to that of topotecan in 9 of 17 tumors. The novel drug was also markedly effective against slowly growing tumors (A549 lung carcinoma and HT29 colon carcinoma) when a daily protracted treatment was used to fully exploit the therapeutic potential of camptothecins., Conclusions: The unusual potency of ST1481 in a variety of tumor cell lines suggests the ability of the drug to overcome several resistance factors. The profile of antitumor efficacy further supports the therapeutic interest in the novel analogue and provides a rational basis for clinical evaluation in selected tumor types.