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AimThe current study was conducted to assess the effects of various surface treatments on the implant surface. Materials and MethodsA total of 45 dental implants measuring 16 mm in length and 5 mm in diameter were used, along with the appropriate abutments. Depending on the surface treatment used, the samples were randomly split into three groups, with 15 implants in each group: Group 1: Control, Group 2: UV light-treated, Group 3: Sandblasted and acid-etched (SLA)-treated. After surface treatment, a scanning electron microscope (SEM) was used to assess the test samples’ surface properties. All sample images were captured using a 3000× magnification. After all three groups’ surfaces were treated, the surface roughness was measured using a digital optical profilometer with a stylus speed of 0.5 mm/s that was connected to computer software. ResultsThe maximum surface roughness was found in the group treated with SLA (0.714 ± 0.12), followed by the group treated with UV light (0.692 ± 0.09) and the control group (0.516 ± 0.12). There was a significant difference found between different surface treatment methods. ConclusionThe present study concluded that the group that received the SLA treatment had the highest surface roughness when compared to the UV light and control groups.

Aim: The current study was conducted to assess the effects of various surface treatments on the implant surface. Materials and Methods: A total of 45 dental implants measuring 16 mm in length and 5 mm in diameter were used, along with the appropriate abutments. Depending on the surface treatment used, the samples were randomly split into three groups, with 15 implants in each group: Group 1: Control, Group 2: UV light-treated, Group 3: Sandblasted and acid-etched (SLA)-treated. After surface treatment, a scanning electron microscope (SEM) was used to assess the test samples' surface properties. All sample images were captured using a 3000× magnification. After all three groups' surfaces were treated, the surface roughness was measured using a digital optical profilometer with a stylus speed of 0.5 mm/s that was connected to computer software. Results: The maximum surface roughness was found in the group treated with SLA (0.714 ± 0.12), followed by the group treated with UV light (0.692 ± 0.09) and the control group (0.516 ± 0.12). There was a significant difference found between different surface treatment methods. Conclusion: The present study concluded that the group that received the SLA treatment had the highest surface roughness when compared to the UV light and control groups. [ABSTRACT FROM AUTHOR]

The effect of phosphorylation events on the sequence-independent binding proteins of p53 is examined using two DNA substrates, one resembling Holliday junctions and the other containing extra base bulges. Gel retardation assays showed that diphosphorylation of serine 392 in the C-terminal domain of p53 greatly reduce Holliday junction and lesion recognition.

Objective: Use next-generation sequencing (NGS) technology to improve our diagnostic yield in patients with suspected genetic disorders in the Asian setting.Design: A diagnostic study conducted between 2014 and 2019 (and ongoing) under the Singapore Undiagnosed Disease Program. Date of last analysis was 1 July 2019.Setting: Inpatient and outpatient genetics service at two large academic centres in Singapore.Patients: Inclusion criteria: patients suspected of genetic disorders, based on abnormal antenatal ultrasound, multiple congenital anomalies and developmental delay.Exclusion Criteria: patients with known genetic disorders, either after clinical assessment or investigations (such as karyotype or chromosomal microarray).Interventions: Use of NGS technology-whole exome sequencing (WES) or whole genome sequencing (WGS).Main Outcome Measures: (1) Diagnostic yield by sequencing type, (2) diagnostic yield by phenotypical categories, (3) reduction in time to diagnosis and (4) change in clinical outcomes and management.Results: We demonstrate a 37.8% diagnostic yield for WES (n=172) and a 33.3% yield for WGS (n=24). The yield was higher when sequencing was conducted on trios (40.2%), as well as for certain phenotypes (neuromuscular, 54%, and skeletal dysplasia, 50%). In addition to aiding genetic counselling in 100% of the families, a positive result led to a change in treatment in 27% of patients.Conclusion: Genomic sequencing is an effective method for diagnosing rare disease or previous 'undiagnosed' disease. The clinical utility of WES/WGS is seen in the shortened time to diagnosis and the discovery of novel variants. Additionally, reaching a diagnosis significantly impacts families and leads to alteration in management of these patients. [ABSTRACT FROM AUTHOR]

Aim: The aim of the study was to evaluate the patients' expectation and satisfaction with complete dentures before and after the treatment concerning retention, mastication, phonetics, esthetics, and comfort among the first-time denture wearers and already denture wearers and to find the correlation between duration of denture-wearing experience and satisfaction. Settings and Design: Cross sectional survey. Materials and Methods: A questionnaire was given to the patient before the onset of the treatment, and ratings were given by the patient for expectation regarding retention, mastication, phonetics, esthetics, and comfort. Patient-related variables regarding previous denture experience and duration of wearing were also recorded. After the treatment was completed, the patient was asked to complete the same questionnaire to assess the satisfaction. Statistical Analysis Used: Descriptive statistics, frequency and percentage analysis, Wilcoxon signed-rank test, Mann-Whitney U-test. Results: Expectation and satisfaction were met for all the variables except mastication (P = 0.004) for first-time wearers and except mastication (P = 0.001) and comfort (P = 0.007) among existing denture wearers. However, no significant correlation was elicited between patient expectation and satisfaction in both these groups as the overall mean satisfaction percentage was similar. A clinical significance of P = 0.037 was seen with respect to the duration of denture-wearing experience among existing wearers. Regression model analysis showed a decreased satisfaction with increased duration of wearing (r = 0.396). Conclusions: Satisfaction and expectation were found to be almost the same irrespective of whether they are first-time wearers or existing wearers. With the increase in the duration of denture-wearing experience, the satisfaction of the patients decreased. [ABSTRACT FROM AUTHOR]

Type II DNA topoisomerases actively reduce the fractions of knotted and catenated circular DNA below thermodynamic equilibrium values. To explain this surprising finding, we designed a model in which topoisomerases introduce a sharp bend in DNA. Because the enzymes have a specific orientation relative to the bend, they act like Maxwell's demon, providing unidirectional strand passage. Quantitative analysis of the model by computer simulations proved that it can explain much of the experimental data. The required sharp DNA bend was demonstrated by a greatly increased cyclization of short DNA fragments from topoisomerase binding and by direct visualization with electron microscopy.

Thephase behavior and mesoscopic inhomogeneities in the ternarysystem of tertiary butyl alcohol (TBA), water, and propylene oxide(PO) have been studied by static and dynamic light scattering, gaschromatography, mass spectrometry, and molecular dynamics simulations.Mesoscale inhomogeneities are observed in this system in a broad rangeof PO concentrations, from 0.02 to about 65 mass %, and at certainTBA/water mass ratios varying from about 3/97 to about 30/70. ThisTBA/water composition domain corresponds to a region where short-livedmicelle-like molecular clustering and thermodynamic anomalies areobserved in the TBA–water binary system. At dilute PO concentrations(0.02 to about 1 mass %) the mesoscale inhomogeneities are Browniandiffusive droplets, with a size of the order of a hundred nanometers.We hypothesize that these droplets have a hydrophobic core enrichedby oily impurities and oligomerized PO molecules. A hydrogen-bondedlayer of TBA, water, and PO molecules surrounds this hydrophobic core.At high PO concentrations (beyond 50 mass %), the interfacial curvatureof the mesoscopic inhomogeneities changes its sign and the exteriorsof these inhomogeneities become hydrophobic. The inversion of theinternal curvature may result in the formation of a spongelike bicontinuousmesoscale structure at intermediate PO concentrations. This mesostructureappears to be at a nonequilibrium state, although extremely long-lived. [ABSTRACT FROM AUTHOR]

Abstract: Hydrotropes are amphiphilic molecules that are too small to spontaneously form equilibrium structures in aqueous solutions, but form dynamic, non-covalent assemblies, referred to as clusters. In the presence of a hydrophobic compound, these clusters seem to get stabilized leading to the formation of long-lived, highly stable mesoscopic droplets, a phenomenon that we call “mesoscale solubilization”. In this work, we focus on the unusual mesoscopic properties of aqueous solutions of a nonionic hydrotrope, namely tertiary butyl alcohol (TBA), on addition of various hydrophobic compounds. Aqueous TBA solutions, in about 3–8mol% TBA concentration range and about 0–25°C temperature range, show the presence of short-ranged (∼0.5nm), short-lived (tens of picoseconds) molecular clusters which result in anomalies of the thermodynamic properties. These clusters are transient but do not relax by diffusion, thus distinctly different from conventional concentration fluctuations. In this concentration and temperature range, upon the addition of a third (more hydrophobic) component to TBA–water solutions, long-lived mesoscopic droplets of about 100nm size are observed. In this work, we clarify the ambiguity behind the definition of solubility and elucidate the phenomenon of mesoscale solubilization. A systematic study of the macroscopic and mesoscopic phase behavior of three ternary systems TBA–water-propylene oxide, TBA–water-isobutyl alcohol, and TBA–water-cyclohexane has been carried out. We differentiate between molecular solubility, mesoscale solubilization, and macroscopic phase separation. We have confirmed that practically stable aqueous colloids can be created from small molecules, without addition of surfactants or polymers. Such kind of novel materials may find applications in the design of various processes and products, ranging from pharmaceuticals to cosmetics and agrochemicals. [Copyright &y& Elsevier]

Small amphiphilic molecules, also known as hydrotropes, are too small to form micelles in aqueous solutions. However, aqueous solutions of nonionic hydrotropes show the presence of a dynamic, loose, non-covalent clustering in the water-rich region. This clustering can be viewed as “micelle-like structural fluctuations”. Although these fluctuations are short ranged (∼1 nm) and short lived (10 ps–50 ps), they may lead to thermodynamic anomalies. In addition, many experiments on aqueous solutions of hydrotropes show the occasional presence of mesoscale (∼100 nm) inhomogeneities. We have combined results obtained from molecular dynamics simulations, small-angle neutron scattering, and dynamic light-scattering experiments carried out on tertiary butyl alcohol (hydrotrope)–water solutions and on tertiary butyl alcohol–water–cyclohexane (hydrophobe) solutions to elucidate the nature and structure of these inhomogeneities. We have shown that stable mesoscale inhomogeneities occur in aqueous solutions of nonionic hydrotropes only when the solution contains a third, more hydrophobic, component. Moreover, these inhomogeneities exist in ternary systems only in the concentration range where structural fluctuations and thermodynamic anomalies are observed in the binary water–hydrotrope solutions. Addition of a hydrophobe seems to stabilize the water–hydrotrope structural fluctuations, and leads to the formation of larger (mesoscopic) droplets. The structure of these mesoscopic droplets is such that they have a hydrophobe-rich core, surrounded by a hydrogen-bonded shell of water and hydrotrope molecules. These droplets can be extremely long-lived, being stable for over a year. We refer to the phenomenon of formation of mesoscopic droplets in aqueous solutions of nonionic hydrotropes containing hydrophobes, as mesoscale solubilization. This phenomenon may represent a ubiquitous feature of nonionic hydrotropes that exhibit clustering in water, and may have important practical applications in areas, such as drug delivery, where the replacement of traditional surfactants may be necessary. [ABSTRACT FROM AUTHOR]

We have resolved a long-standing issue in the discussion on the origin of the mesoscale inhomogeneities observed in aqueous solutions of tertiary butyl alcohol (TBA). We have shown that the formation of stable mesoscale particles (of about 100 nm in size) can be triggered by the addition of trace amounts of propylene oxide (an impurity expected to be present in all commercial samples of TBA) to a solution, which was previously filtered at a low temperature to remove these inhomogeneities. We hypothesize that these particles are aggregates of mixed clathrate-hydrates that are formed through the stabilization of fluctuations of the intrinsic structure in TBA aqueous solutions by the clathrate-forming ability of propylene oxide. [ABSTRACT FROM AUTHOR]

Aim: The aim of this study was to examine the impact of thermocycling on the flexural strength and development of surface flaws on the glazed surface of porcelain laminate veneer restorations with and without resin luting cement. Materials and Methods: 80 Vitadur alpha dentin porcelain discs (10 mm diameter, 0.9 mm thickness) were glazed on one side and divided into two groups: A (porcelain laminate veneer only without resin luting cement) and B (porcelain laminate veneer luted with resin cement), each containing 40 discs. The discs in groups A and B were then thermocycled at different temperatures and were subjected to SEM analysis to evaluate the effect of thermocycling on crack propagation. Mean flexural strength was determined by using the ball-on-ring test. Student's t-test was used to find out the difference between strength values of the thermocycled porcelain discs and discs luted with resin cement. Results: SEM analysis revealed crack propagation in the subgroups subjected to extremes of temperature, i.e., 4 ± 1°C, 37 ± 1°C and 4 ± 1°C, 65 ± 1°C in the porcelain laminate veneers luted with resin cement. Flexural strength analysis revealed superior flexural strength for porcelain laminate veneers: 88.58 ± 6.94 Mpa when compared to porcelain laminate veneers luted with resin cement: 8.42 ± 2.60 MPa. Results were tabulated and statistically analyzed using Student's t-test. Conclusion: Laminate veneer specimens exhibited greater flexural strength than those which were luted with resin cements. Laminate veneer specimens luted with resin cement and subjected to extremes of temperature, 4 ± 1°C and 37 ± 1°C and 4 ± 1°C and 65 ± 1°C, showed a marked decrease in flexural strength. After thermocycling at extremes of temperature, laminate veneer specimens luted with resin cement showed crack propagation. Fit of laminate veneers cannot / should not be compensated by the thickness of luting agent. [ABSTRACT FROM AUTHOR]

Fas, a TNF family receptor, is activated by the mem-brane protein Fas ligand expressed on various immune cells. Fas signaling triggers apoptosis and induces in-flammatory cytokine production. Among the Fas-induced cytokines, the IL-1βfamily cytokines require proteolysis to gain biological activity. Inflammasomes, which respond to pathogens and danger signals, cleave IL-1 β cytokines via caspase-1. However, the mecha-nisms by which Fas regulates IL-1 βactivation remain unresolved. In this article, we demonstrate that macro-phages exposed to TLR ligands upregulate Fas, which renders them responsive to receptor engagement by Fas ligand. Fas signaling activates caspase-8 in macro-phages and dendritic cells, leading to the maturation of IL-1 (βand IL-18 independently of inflammasomes or RIP3. Hence, Fas controls a novel noncanonical IL-1β activation pathway in myeloid cells, which could play an essential role in inflammatory processes, tumor surveillance, and control of infectious diseases. [ABSTRACT FROM AUTHOR]