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Although biologically appealing, the concept of tissue regeneration underlying first- and second-generation cell therapies has failed to translate into consistent results in clinical trials. Several types of cells from different origins have been tested in pre-clinical models and in patients with acute myocardial infarction (AMI). Mesenchymal stromal cells (MSCs) have gained attention because of their potential for immune modulation and ability to promote endogenous tissue repair, mainly through their secretome. MSCs can be easily obtained from several human tissues, the umbilical cord being the most abundant source, and further expanded in culture, making them attractive as an allogeneic "of-the-shelf" cell product, suitable for the AMI setting. The available evidence concerning umbilical cord-derived MSCs in AMI is reviewed, focusing on large animal pre-clinical studies and early human trials. Molecular and cellular mechanisms as well as current limitations and possible translational solutions are also discussed. [ABSTRACT FROM AUTHOR]

Statement of problem Framework longevity is a key factor for the success of complete-arch prostheses and commonly depends on the welding methods. However, no consensus has been reached on the joint design and welding type for improving framework resistance. Purpose The purpose of this study was to assess the effect of different joint designs and welding methods with tungsten inert gas (TIG) or laser to join titanium alloy bars (Ti-6Al-4V). Material and methods Seventy titanium alloy bar specimens were prepared (3.18 mm in diameter × 40.0 mm in length) and divided into 7 groups (n=10): the C-control group consisting of intact specimens without joints and the remaining 6 groups consisting of specimens sectioned perpendicular to the long-axis and rejoined using an I-, X30-, or X45-shaped joint design with TIG welding (TI, TX30, and TX45) or laser welding (LI, LX30, and LX45). The specimens were tested with 3-point bending. The fracture surfaces were first evaluated with stereomicroscopy to measure the weld penetration area and then analyzed with scanning electron microscopy (SEM). The data were statistically analyzed with 2-way ANOVA and the Tukey post hoc test, 1-way ANOVA and the Dunnett test, and the Pearson correlation test (α=.05). Results Specimens from the X30 and X45 groups showed higher flexural strength ( P <.05) and welded area ( P <.05) than specimens from the I groups, regardless of the welding type. TIG welded groups showed significantly higher flexural strength than the laser groups ( P <.05), regardless of the joint design. TIG welding also resulted in higher welded areas than laser welding for the I-shaped specimens. No significant differences were found for the weld penetration area in the X45 group, either for laser or TIG welding. SEM analysis showed more pores at the fracture surfaces of the laser specimens. Fracture surfaces indicative of regions of increased ductility were detected for the TIG specimens. Conclusions TIG welding resulted in higher flexural strength for the joined titanium specimens than laser welding. For both welding methods, X30- and X45-shaped joint designs resulted in higher flexural strength and welding penetration than the I-shaped joint design. [ABSTRACT FROM AUTHOR]

Introduction The aim of this study was to evaluate the influence of a ferrule, post system, and length on the stress distribution of weakened root-filled teeth. Methods The investigation was conducted by using 3-dimensional (3D) finite element analysis. A sound tooth and 8 3D models of a weakened root-filled central incisor were generated using computer-aided design/computer-aided manufacturing software. The models were created without a ferrule and with a 2.0-mm ferrule, restored with a relined glass fiber post or a cast post and core (Cpc), and 12.0- and 7.0-mm post lengths. Each 3D model was imported using ∗.STEP files to the finite element software for mesh generation. The models were subjected to 100-N oblique loading at the palatal surface, and the results were evaluated by von Mises criterion and maximum principal stress distribution. Results Finite element analysis showed that the Cpc models showed elevated stress levels in the root canal regardless of the presence of a ferrule. Relined glass fiber post models showed homogeneous stress distribution to the dentin external surface similar to the sound tooth model. Without a ferrule, Cpc with a 7- or 12-mm length promoted high levels of tensile stress inside the root canal. Conclusions Ferrule presence promoted more satisfactory stress distribution to the roots. Post length influenced the stress distribution only for the models restored with a cast post and core. High levels of tensile stress inside the root canals were verified with a cast post and core, which should be avoided to rehabilitate weakened roots, mainly in the absence of a ferrule. [ABSTRACT FROM AUTHOR]

Abstract: Introduction: This study aimed to evaluate the influence of flexion angles produced by files during root canal instrumentation on the final form of the apical stop. Methods: Sixty human lower incisors were divided into 3 groups (n = 20). After access preparation and working length determination, radiographs were taken from a mesiodistal and buccolingual direction with #15 K-file inserted to working length. Teeth from FlexM group were instrumented with stainless steel Flexofiles up to #40 file. For ProM and ProR groups, hand ProTaper Universal and ProTaper Universal rotary files were used, respectively, up to file F4. New radiographs were taken as previously described. After gutta-percha insertion, the apex of each specimen was ground, allowing gutta-percha visualization, and an image of the apex was captured to identify root canal deformation with computer software. The flexion of files was evaluated from both initial and final radiographs as the angle formed between the divergence of the file path and its virtual image represented by the direction taken by the file in the absence of curvature. Results: FlexM group presented the highest variation in flexion angles compared with ProM (P = .112) and ProR (P = .024) groups. Nickel-titanium rotary system (ProR) reduced apical stop deformation compared with the manual techniques that used nickel-titanium (P = .011) or stainless steel (P = .025) files. Conclusions: Force vectors caused by the flexion angles of the files during the instrumentation of curved canals promoted apical stop deformation. ProTaper Universal rotary files showed less apical deformation than hand ProTaper Universal and stainless steel files. [Copyright &y& Elsevier]

Statement of problem: Unresolved controversy exists concerning the best technique for restoring endodontically treated teeth. Prefabricated posts have been recommended with some debate as a method of restoring pulpless teeth before placement of the final restoration. Purpose: The purpose of this in vitro study was to evaluate the effect on the strain, fracture resistance, and fracture mode of endodontically treated human incisors of 4 types of restorations with or without glass fiber posts after thermal cycling. Material and methods: Ninety human maxillary central incisors were selected and divided into 1 control group and 8 treatment groups (n=10). The teeth were endodontically treated and received 2 large Class III preparations simulating coronal destruction. The teeth were then restored with or without glass fiber posts and by using 4 restorative techniques: direct composite resin, direct composite veneer, feldspathic ceramic veneer, or a feldspathic ceramic crown. After artificial aging by thermal cycling, the incisors were loaded at a 135-degree angle, and the strain was measured by using strain gauges placed on the facial and proximal root surfaces. Specimens were subsequently loaded to the point of fracture. Strain and fracture resistance results were analyzed by a 1-way and 2-way ANOVA, followed by the Tukey HSD and Dunnett tests (α=.05). Results: One-way analyses showed that the control group and the direct composite resin restoration with and without post groups presented significantly higher fracture resistance values (P<.001). Two-way analyses showed no significant differences for the post system. Proximal strain values were higher in the control and composite resin groups and lower in the feldspathic ceramic groups. Conclusions: The presence of glass fiber posts did not increase the fracture resistance of endodontically treated incisors. Conservative composite resin restorations showed higher fracture resistance values. [Copyright &y& Elsevier]

Statement of problem: Unresolved controversy exists concerning the remaining coronal tooth structure of anterior endodontically treated teeth and the best treatment option for restoring them. Purpose: The purpose of this study was to evaluate the effect of post, core, crown type, and ferrule presence on the deformation, fracture resistance, and fracture mode of endodontically treated bovine incisors. Material and methods: One hundred and eighty bovine incisors were selected and divided into 12 treatment groups (n=15). The treatment variations were: with or without ferrule, restored with cast post and core, glass fiber post with composite resin core, or glass fiber post with fiber-reinforced core, and metal- or alumina-reinforced ceramic crown (n=15). The restored incisors were loaded at a 135-degree angle, and the deformation was measured using strain gauges placed on the buccal and proximal root surfaces. Specimens were subsequently loaded to the point of fracture. Strain and fracture resistance results were analyzed by 3-way ANOVA and Tukey HSD tests (α=.05). Results: Ferrule presence did not significantly influence the buccal strain and fracture resistance for the ceramic crown groups, irrespective of core and crown type. Ferrule presence resulted in lower strains and higher fracture resistance in the metal crown groups, irrespective of core. The cast post and core showed lower strain values than groups with glass fiber posts when restored with metal crowns. Conclusions: Core type did not affect the deformation and fracture resistance of endodontically treated incisors restored with alumina-reinforced ceramic crowns. The presence of a ferrule improved the mechanical behavior of teeth restored with metal crowns, irrespective of core type. [Copyright &y& Elsevier]

Cancer is still one of the deadliest diseases worldwide despite the efforts in its early detection and treatment strategies. However, most chemotherapeutic agents still present side effects in normal tissues and acquired resistance that limit their efficacy. Spiropyrazoline oxindoles might be good alternatives as they have shown antiproliferative activity in human breast and colon cancer cell lines, without eliciting cytotoxicity in healthy cells. However, their potential for ovarian cancer was never tested. In this work, the antiproliferative activity of five spiropyrazoline oxindoles was assessed in ovarian cancer cells A2780 and the biological targets and mechanism of action of the most promising compound evaluated. Compound 1a showed the highest antiproliferative effect, as well as the highest selectivity for A2780 cells compared to healthy fibroblasts. This antiproliferative effect results from the induction of cell death by mitochondria-mediated apoptosis and autophagy. In vitro DNA interaction studies demonstrated that 1a interacts with DNA by groove-binding, without triggering genotoxicity. In addition, 1a showed a strong affinity to bovine serum albumin that might be important for further inclusion in drug delivery platforms. Proteomic studies reinforced 1a role in promoting A2780 endoplasmatic reticulum (ER) stress by destabilizing the correct protein folding which triggers cell death via apoptosis and autophagy. [ABSTRACT FROM AUTHOR]

Abstract: Objectives: Innumerous modifications have been proposed for the microtensile test since its introduction; however, testing parameters are not often well described and wide variations in bond strength are commonly reported. The aim of this study was to evaluate the effect of the test specimen''s gripping device, specimen geometry and fixation method on microtensile bond strength, failure mode, and stress distribution when using an etch-and-rinse 2-step adhesive system bonded to human dentin. Methods: Resin-based composite bonded to occlusal dentin from 21 human molars was used to fabricate dumbbell- and stick-shaped test specimens which were divided into three groups: Di – dumbbell-specimens placed in a Dircks device; GeS – stick-specimens gripped in a Geraldeli''s device with Superglue; GeZ – stick-specimens gripped in a Geraldeli''s device with Zapit. Specimens were tested to failure in tensile mode and the failure mode was examined under stereomicroscopy and fracture initiation sites were verified by scanning electron microscopy and energy dispersive X-ray spectroscopy. Three-dimensional models of each device/specimen were created and finite element calculations were performed. Results: The effect of the gripping devices on the bond strength was not significant, unless the bond test areas were normalized. The failure mode was influenced by the type of device. Dircks device was less sensitive to human error than Geraldeli''s, and produced a more uniform stress distribution at the dumbbell specimen adhesive layer than did the Geraldeli''s device at the stick layer. Significance: Microtensile testing parameters can directly influence the results and consequently inter-study comparisons. [Copyright &y& Elsevier]

Streptococcus dysgalactiae subsp. dysgalactiae (SDSD) are considered exclusive animal pathogens; however, a putative zoonotic upper limb cellulitis, a prosthetic joint infection and an infective endocarditis were described in humans. To unravel if bovine SDSD isolates are able to infect human cells, the adherence and internalization to human primary keratinocytes of two bovine SDSD strains isolated from milk collected from udder were analyzed. Bacterial adhesion assays and confocal microscopy indicate a high adherence and internalization of SDSD isolates to human cells, suggesting for the first time the ability of bovine isolates to infect human cells. [ABSTRACT FROM AUTHOR]

Aim: To evaluate the real need for coronary access after transcatheter aortic valve implantation (TAVI).Methods and Results: Prospective observational single-center registry, including 563 consecutive patients who underwent TAVI between April 2008 and November 2018, with both self- and balloon-expandable valves in a tertiary European center. Mean age was 82.4 ± 6.9 years, 53.3% were female, 16% had previous history of coronary artery bypass grafting, 33% of previous percutaneous coronary intervention (PCI), and 16.6% of myocardial infarction (MI). Twenty-four percent of the patients were revascularized within one year before TAVI in preparation for the procedure. Median Society of Thoracic Surgeons score was 4.82 (IQ 2.84). In a median follow-up of 24 months (IQ 21.5), 18 patients (3.2%) were identified as potentially in need for invasive coronary angiography: 9 (1.6%) in the setting of stable coronary artery disease and 9 (1.6%) for an acute coronary syndrome. A total of 11 PCIs were performed in 9 patients, with a complete success rate of 63.6%. Procedures that were unsuccessful or partially unsuccessful were due to the inability to cross the stent or the drug-eluting balloon through the valve struts or misplacement within the coronary artery due to lack of catheter support.Conclusion: In this population, a strategy of previous guideline-directed revascularization before TAVI was associated with a low rate of MI and repeated need of coronary access, with a scattered distribution over time. Assuring future access to coronary arteries in patients at increased risk may depend on the revascularization strategy rather than device selection. [ABSTRACT FROM AUTHOR]

The syntheses of the heterometallic sodium and potassium-dioxidovanadium 2D polymers, [NaVO 2 (1κN OO' ;2κ O"- L)(H 2 O)] n (1) and [KVO 2 (1κN OO' ;2κ O' ;3κ O"- L)(EtOH)] n (2) (where the κ notation indicates the coordinating atoms of the polydentate ligand L) derived from (3,5-di- tert -butyl-2-hydroxybenzylidene)-2-hydroxybenzohydrazide (H 2 L) are reported. The polymers were characterized by IR, NMR, elemental analysis and single crystal X-ray diffraction analysis. The antiproliferative potential of 1 and 2 was examined towards four human cancer cell lines (ovarian carcinoma, A2780, colorectal carcinoma, HCT116, prostate carcinoma, PC3 and breast adenocarcinoma, MCF-7cell lines) and normal human fibroblasts. Complex 1 and 2 showed the highest cytotoxic activity against A2780 cell line (IC 50 8.2 and 11.3 μM, respectively) with 1 > 2 and an IC 50 in the same range as cisplatin (IC 50 3.4 μM; obtained in the same experimental conditions) but, interestingly, with no cytotoxicity to healthy human fibroblasts for concentrations up to 75 μM. This high cytotoxicity of 1 in ovarian cancer cells and its low cytotoxicity in healthy cells demonstrates its potential for further biological studies. Our results suggest that both complexes induce ovarian carcinoma cell death via apoptosis and autophagy, but autophagy is the main biological cause of the reduction of viability observed and that ROS (reactive oxygen species) may play an important role in triggering cell death. The antiproliferative potential of heterometallic sodium and potassium-dioxidovanadium 2D polymers derived from aroylhydrazone ligand was examined towards A2780, a human ovarian carcinoma cell line. The sodium-dioxidovanadium polymer exhibits high cytotoxicity towards ovarian cancer cells. Unlabelled Image • Syntheses of heterometallic sodium or potassium-dioxidovanadium polymers • They are characterized by single crystal X-ray diffraction analysis. • Antiproliferative potential towards A2780 cell line was examined. • Sodium-dioxidovanadium polymer exhibits high cytotoxicity. [ABSTRACT FROM AUTHOR]

Abstract: The objective of this paper is to critically review the literature regarding the mechanics, geometry, load application and other testing parameters of “micro” shear and tensile adhesion tests, and to outline their advantages and limitations. The testing of multiple specimens from a single tooth conserves teeth and allows research designs not possible using conventional ‘macro’ methods. Specimen fabrication, gripping and load application methods, in addition to material properties of the various components comprising the resin–tooth adhesive bond, will influence the stress distribution and consequently, the nominal bond strength and failure mode. These issues must be understood; as should the limitations inherent to strength-based testing of a complicated adhesive bond joining dissimilar substrates, for proper test selection, conduct and interpretation. Finite element analysis and comprehensive reporting of test conduct and results will further our efforts towards a standardization of test procedures. For the foreseeable future, both “micro” and “macro” bond strength tests will, as well as various morphological and spectroscopic investigative techniques, continue to be important tools for improving resin–tooth adhesion to increase the service life of dental resin-based composite restorations. [Copyright &y& Elsevier]