Adhesive Bonding to Computer-aided Design/ Computer-aided Manufacturing Esthetic Dental Materials: An Overview.

AIM: To review the adhesive bonding to different computer-aided design/computer-aided manufacturing (CAD/CAM) esthetic restorative materials. BACKGROUND: The use of CAD/CAM esthetic restorative materials has gained popularity in recent years. Several CAD/ CAM esthetic restorative materials are commercially available. Adhesive bonding is a major determinant of success of CAD/ CAM restorations. Review result: An account of the currently available bonding strategies are discussed with their rationale in various CAD/ CAM materials. CONCLUSION: Different surface treatment methods as well as adhesion promoters can be used to achieve reliable bonding of CAD/CAM restorative materials. Selection of bonding strategy to such material is determined based on its composition. Further evidence is required to evaluate the effect of new surface treatment methods, such as nonthermal atmospheric plasma and self-etching ceramic primer on bonding to different dental ceramics. CLINICAL SIGNIFICANCE: An understanding of the currently available bonding strategies to CA/CAM materials can help the clinician to select the most indicated system for each category of materials.

Electronic, optical, and thermoelectric characteristics of (Ae)xFBiS2 (Ae=Sr, Ba, and x=1.7) layered materials useful in optical modulator devices.

The recent discovery of superconductivity behavior in the mother BiS2-layered compounds has captivated the attention of several physicists. The crystal structure of superconductors with alternate layers of BiS2 is homologous to that of cuprates and Fe-based superconductors. The full-potential linearized augmented plane-wave (FP-LAPW) technique was utilized to investigate the electronic structures and density of states in the vicinity of the Fermi energy of SrFBiS2 and BaFBiS2 compounds under the electron carriers doping. The introduction of electron doping (carries doping) reveals that the host compounds SrFBiS2 and BaFBiS2 exhibit features indicative of superconductivity. This carrier doping of SrFBiS2 and BaFBiS2 compounds (electron-doped) has a significant impact on the lowest conduction states near the Fermi level for the emergence of the superconducting aspect. The electron doping modifies and induces changes in the electronic structures with superconducting behavior in (Ae)1.7FBiS2(Ae=Sr,Ba) compounds. A Fermi surface nesting occurred under the modification of electrons (carriers) doping in the host compounds SrFBiS2 and BaFBiS2. Furthermore, the optical characteristics of the carrier-doped SrFBiS2 and BaFBiS2 compounds are simulated. Due to the anisotropic behavior, the optical properties of these materials based on BiS2 demonstrate a pronounced polarization dependency. The starting point at zero photon energy in the infrared region is elucidated by considering the Drude features in the optical conductivity spectra of SrFBiS2 and BaFBiS2 compounds, when the electron carriers doping is applied. It was clearly noticed that the spin-orbit coupling (SOC) influences the electronic band structures, density of states, Femi surface, and optical features because of the heavy Bismuth atom, which may disclose fascinating aspects. Further, we conducted simulations to assess the thermoelectric properties of these mother compounds. The two BiS2-layered compounds could be suitable for practical thermoelectric purposes and are highlighted through assessment of electrical conductivity, thermal conductivity, Seebeck coefficient, and power factor. As a result, we propose that the mechanisms of superconducting behavior in BiS2 family may pave new avenues for investigating the field of unconventional superconductivity. It may also provide new insights into the origin of high-Tc superconductivity nature.

Evaluation of an online website-based platform for cephalometric analysis.

BACKGROUND: The purpose of our study was to assess the reproducibility of linear and angular measurements of cephalogram tracings made with an online website-based platform CephX® vs. tracings made using the FACAD® computer software. METHODS: Thirty cephalometric radiographs were selected randomly to be used in this study. A total of 16 landmarks and 16 measurements (8 linear and 8 angular) were defined. We used paired t-test to compare mean differences between both methods. Concordance Correlation Coefficient (CCC) and Bland-Altman analyses were used to evaluate reproducibility of measurements. The level of statistical significance was set at P < 0.05. RESULTS: We did not find a statistically significant mean difference between the two methods except for two angular measurements SNA, FMA and one linear measurement Pg to NB. The highest magnitude of the difference between sample means was 1.9° and 0.78 mm for the angular and linear measurements respectively. The SE value was less than 0.1° for the angular measurements and less than 0.3 mm for the linear measurements. All parameters except POG to NB showed moderate to almost perfect agreement (>0.90). CONCLUSION: The measurements obtained by both softwares FACAD® and CephX® are reproducible. Although significant differences were detected for some measurements, all differences were not clinically significant.

Thymoquinone and curcumin modify inducible nitric oxide synthase, caspase 3, and thioredoxin immunohistochemical expression in acetaminophen hepatotoxicity.

BACKGROUND: Acetaminophen (APAP) hepatotoxicity is characterised by an extensive oxidative stress due to depletion of glutathione (GSH), which results in massive lipid peroxidation and subsequent liver injury. The current paradigm suggests that mitochondria are the main source of reactive oxygen species (ROS), which impair mitochondrial function and are responsible for cell signalling resulting in cell death. This study was designed to compare the potential impact of thymoquinone (THQ), and/or curcumin (CURC) on liver injury induced by APAP toxicity in rats. MATERIALS AND METHODS: Serum levels of alanine transaminase, aspartate transaminase, total bilirubin, and total protein were measured. In addition, liver nitric oxide (NO), malondialdehyde, reduced glutathione (GSH), and superoxide dismutase (SOD) were estimated. Moreover, these biochemical parameters were confirmed by histopathological and immunohistochemical investigations for the expression of thioredoxin, iNOS and caspase 3. RESULTS: Acetaminophen toxicity elevated most of the above-mentioned parameters but decreased GSH, SOD, and total protein levels. Histologically, liver sections demonstrated liver injury characterised by hepatocellular necrosis with nuclear pyknosis, karyorrhexis and karyolysis. Immunohistochemical study revealed increased expression of iNOS and caspase 3 proteins, while the thioredoxin protein expression was decreased. CONCLUSIONS: Treatment with the THQ and CURC regulated the biochemical and histopathological alterations induced by APAP toxicity. It was concluded that the combination strategy of THQ and CURC might be considered as a potential antidote in combating liver injury induced by APAP with minimal side effects.

Stent-assisted coiling of posterior inferior cerebellar artery aneurysm complicated by arterial avulsion.

BACKGROUND: Rapid development of new devices and techniques in endovascular neurosurgery allows treatment of complex intracranial vascular lesions. These treatments, however, are not without risk. We report a case of unusual vascular laceration during stent-assisted coiling of a posterior inferior cerebellar artery (PICA) aneurysm. CASE PRESENTATION: A 75-year-old female with a recurrent, previously coiled PICA aneurysm developed avulsion of the parent vessel followed by fatal bleeding while an attempt was made to place a microcatheter across the aneurysmal neck for stent-assisted coiling. CONCLUSIONS: Pathological examination was performed to understand the mechanism of the rupture. The most likely mechanism was straightening of the significant vascular tortuosity, excessive tension on the vessel origin and avulsion upon advancement of the microcatheter over the microguidewire.

DDX17 (P72), a Sox2 binding partner, promotes stem-like features conferred by Sox2 in a small cell population in estrogen receptor-positive breast cancer.

We have previously demonstrated the existence of two phenotypically distinct cell subsets in estrogen receptor (ER)-positive breast cancer (BC) based on their differential response to a Sox2 reporter (SRR2), with reporter responsive (RR) cells being more tumorigenic and stem-like than reporter unresponsive (RU) cells. To delineate the molecular mechanisms underlying this phenotypic dichotomy, we tested our hypothesis that Sox2, which is a key regulator of the RR phenotype, is under the control of its binding partners. In this study, we focused on DDX17, known to be a transcription co-activator and found to be a Sox2 binding partner by liquid chromatography-mass spectrometry. Using immunoprecipitation, we confirmed the binding between DDX17 and Sox2, although this interaction was largely restricted to RR cells. While DDX17 was found in both the cytoplasm and nuclei in RU cells, it is confined to the nuclei in RR cells. siRNA knockdown of DDX17 in RR cells substantially decreased the Sox2-SRR2 binding and significantly decreased the SRR2 reporter activity without affecting the protein level of Sox2. Using ChIP-PCR, DDX17 knockdown also significantly decreased the binding of Sox2 to genomic SRR2, as well as 3 of its specific gene targets including MUC15, CCND1 and CD133. Correlating with these findings, siRNA knockdown of DDX17 significantly reduced soft agar colony formation and mammosphere formation in RR cells but not RU cells. To conclude, DDX17 is a Sox2-binding protein in ER-positive BC. In RR but not RU cells, DDX17 enhances the tumorigenic and stem-like features of Sox2 by promoting its binding to its target genes.

Growth of nanocrystals and thin films at the water-oil interface.

The use of the water-oil interface provides significant advantages in the synthesis of inorganic nanostructures. Employing the water-toluene interface, luminescent CdS nanocrystals have been obtained at a relatively modest temperature of 35 degrees C. The diameters of the particulates can be varied between 1.0 and 5.0 nm. In addition, we have devised a new method for transferring thin films at the water-toluene interface onto solid substrates. Using this method, thin films consisting of Au and Ag nanocrystals spread over very large areas (square centimetres) are obtained in a single step. These films are directly usable as ingredients of functional devices. We show this by constructing a working amine sensor based on films of Au nanocrystals. The materials obtained have been characterized by X-ray diffraction, scanning and transmission electron microscopy, absorption and emission spectroscopy and charge transport measurements.