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The ability to sense chemical gradients and respond with directional motility and chemical activity is a defining feature of complex living systems. There is a strong interest among scientists to design synthetic systems that emulate these properties. Here, we realize and control such behaviors in a synthetic system by tailoring multivalent interactions of adenosine nucleotides with catalytic microbeads. We first show that multivalent interactions of the bead with gradients of adenosine mono-, di- and trinucleotides (AM/D/TP) control both the phoretic motion and a proton-transfer catalytic reaction, and find that both effects are diminished greatly with increasing valence of phosphates. We exploit this behavior by using enzymatic hydrolysis of ATP to AMP, which downregulates multivalent interactivity in situ. This produces a sudden increase in transport of the catalytic microbeads (a phoretic jump), which is accompanied by increased catalytic activity. Finally, we show how this enzymatic activity can be systematically tuned, leading to simultaneous in situ spatial and temporal control of the location of the microbeads, as well as the products of the reaction that they catalyze. These findings open up new avenues for utilizing multivalent interaction-mediated programming of complex chemo-mechanical behaviors into active systems.

The heterogeneous distribution of lipids and lipid-bound proteins in a plasma membrane has functional advantages. Herein, in a synthetic system, we demonstrate the assembly of three enzymes involved in cascade reactions, in response to the substrate of the first enzyme at the oil–water interface being stabilized by a Zn(II)-metallosurfactant. Then we show substrate-mediated catalytically-active cluster formation of the metallosurfactant in a binary mixture with another non-catalytic surfactant at the interface. The catalytic ability can be tuned by controlling clustering through the addition of phosphate ions. Overall this work demonstrates functionally diverse supramolecular nanoarchitectonics at the oil–water interface. [ABSTRACT FROM AUTHOR]

Aim: This study investigates the interaction of zirconia and polyetheretherketone (PEEK) with indirect composite in fixed dental prostheses. This investigation aimed to assess the shear bond strength (SBS) and color stability of zirconia and PEEK before and after aging, addressing critical concerns in dental restorative applications. Settings and Design: The current in vitro study used 96 samples, 48 of which were divided into two groups, zirconia and PEEK, before and after thermocycling. A dual-axis chewing simulator was used for thermocycling. SBS was measured using a universal testing machine, and color stability was checked using a reflective spectrophotometer. Materials and Methods: Ninety-six samples were categorized into zirconia and PEEK groups, each with subgroups undergoing thermocycling. Samples were prepared using computer-aided design/computer-aided manufacturing milling and veneered with composite resin. Thermocycling involved 10,000 cycles, simulating stress levels equivalent to approximately 1 year of clinical use. SBS was assessed using standardized tests. Stereomicroscopic analysis was performed to evaluate the type of failure. Color stability of the core materials with indirect composite was done using a spectrophotometer before and after aging. Statistical Analysis Used: Statistical analysis included paired t-tests and independent t-tests in SPSS software. Results: The results revealed that SBS values for composite on PEEK decreased from 13.86 ± 0.164 MPa before thermocycling to 13.46 ± 0.185 MPa after thermocycling, with a significant difference (P < 0.005). However, both pre- and postthermocycling values for PEEK were higher than zirconia. The t-test confirmed the lower bond strength of composite to zirconia, with a noteworthy improvement after aging. Stereomicroscopic images revealed adhesive failure for the zirconia group and mixed (adhesive and cohesive) failure for the PEEK group. ΔE values were 3.21 ± 0.127 and 2.93 ± 0.142 for zirconia and PEEK groups, respectively (P < 0.005). Conclusion: Within the limitations of this study, it can be deduced that PEEK is a feasible substitute for zirconia when used in conjunction with indirect composite for the fabrication of dental prostheses. [ABSTRACT FROM AUTHOR]

Aim: The aim of this study was to analyze and compare the stress distribution on dental implants in various positions when used with implant-assisted removable partial dentures. Settings and Design: This was an in vitro study. Materials and Methods: A model representing a mandibular bilateral partially edentulous condition, with missing premolars and molars, was fabricated using epoxy resin. Two implants of similar diameter measuring 4.0 mm × 10 mm (Dentium, Korea) were inserted in the second molar and the second premolar region on either side of the model for comparing the biomechanical effect of various implant locations. Two types of loads 100N and 125N were applied vertically using universal testing machines in the premolar and molar regions. The loads on the implants beneath the cast partial denture were measured by physical stress analysis using a microstrain gauge. Statistical Analysis Used: A comparison of maximum stress observed at the premolar versus molar regions due to the application of the 100N and 125N loads was done using the Mann–Whitney U-test. Results: In physical stress analysis, obtained results were statistically analyzed, and the result was statistically not significant (P = 0.435 at 100N and P = 0.718 at 125N) in positional changes of implant. Conclusion: In the current study, the statistical analysis of physical stress revealed no significant differences in stress values between the loadings at the premolar and molar regions. This suggests that the implant can be placed in either the premolar or molar region based on the availability of bone without affecting stress distribution. [ABSTRACT FROM AUTHOR]

Aim: The conventional technique of implant uncovery using a blade and scalpel is associated with various drawbacks, including profuse bleeding, soft-tissue trauma, delayed healing, and patient noncompliance. Therefore, there is a need to explore the alternative approaches that offer improved accuracy and time efficiency during the cover screw location at the second stage of recovery. This study aims to assess the accuracy and time efficiency of a novel technique that utilizes an apex locator in comparison to conventional locating techniques for implant uncovery. Settings and Design: The study employed a simple randomized controlled trial with a sample size of 161. Materials and Methods: The study employed apex locator (Woodpecker Woodpex III Gold 5th generation) in conjunction with a K-file (Mani k-file #10, 21 mm) for detecting the implant location. The accuracy of the novel technique was determined based on the values measured on the apex locator, with positive values indicating soft-tissue response and negative values indicating the cover screw (metal). The accuracy was cross-verified using radiovisiography (RVG). The clinician-based scoring was also done, considering RVG evaluation, amount of incision given, and ease of the procedure. The time required to locate the cover screw was recorded using a timer for both the novel technique and the conventional method. Statistical Analysis Used: All the recorded values were statistically analyzed using the independent t-test (P < 0.005) with the SPSS software (version 23). Results: The results revealed a significant difference in terms of incision given, ease of treatment, and time taken for the procedure (P < 0.05), while the accuracy of the novel technique was not disturbed (P > 0.05). Conclusion: Based on the findings of this in vivo study, the use of an apex locator as an alternative to conventional methods for detecting cover screw location at the second stage of recovery is recommended. The novel technique demonstrated faster uncovering of implants without posing any risks to the surrounding tissues or implants. [ABSTRACT FROM AUTHOR]

Gaining control over the stability and cleavage of phosphoester and phosphodiester remains a matter of interest for their application in biotechnology to oligonucleotide-based therapeutics. Herein, we report an efficient unactivated phosphoester hydrolysis (stable mono/di/tri/cyclic nucleotide to nucleoside conversion) via a biosupramolecular system comprising of a non-covalent complex of enzyme, alkaline phosphatase (ALP), and Zn(II)-metallosurfactant. We also demonstrate the nucleobase selective activation or inhibition of ALP-mediated oligonucleotide digestion process using that complex. The higher binding affinity of Zn(II)-containing headgroup with phosphate-containing substrate enhanced the effective substrate concentration surrounding the enzyme, which, in turn, results in a drastic decrease in the Michaelis constant (KM), along with an increase in the turnover (kcat). The catalytic activation or inhibition of nucleobase-specific oligonucleotide digestion depends on the hydration, localization of the substrates, and viscosity of the resultant co-assembly upon substrate binding with the enzyme-metallosurfactant complex. Additionally, through isothermal titration calorimetry experiment, we demonstrate enthalpy–entropy change during both the supramolecular binding of (oligo)nucleotides and simultaneous activation/inhibition in catalytic cleavage. Overall, it showed the possible modularity of Zn(II)-mediated biosupramolecular interaction, describing intrinsic thermodynamic aspects in developing complex biocatalytic circuits with nucleobase-specific oligonucleotides inputs, which are relevant in designing nucleic acid-based cargo for drug delivery and bioimaging. [ABSTRACT FROM AUTHOR]

Both micelles and self‐assembled monolayer (SAM)‐protected nanoparticles are capable of efficiently hosting water‐immiscible substrates to carry out organic reactions in aqueous media. Herein, we have analyzed the different catalytic effect of SAM‐protected cationic nanoparticles and cationic surfactants of varying chain length towards base‐catalyzed proton transfer mediated ring‐opening reaction of 5‐nitrobenzisoxazole (NBI) (also known as Kemp Elimination (KE) reaction). We use inorganic phosphate ion or different nucleotide (phosphate‐ligated different nucleoside) as base to promote the reaction on micellar or nanoparticle interface. We find almost 2–3 orders of magnitude higher concentration of surfactants of comparable hydrophobicity required to reach the similar activity which attained by low cationic head group concentration bound on nanoparticle. Additionally, at low concentration of nanoparticle‐bound surfactant or with high surfactant in micellar form, nucleotide‐selectivity has been observed in activating KE reaction unlike free surfactant at low concentration. Finally, we showed enzyme‐mediated nucleotide hydrolysis to generate phosphate ion which in situ upregulate the KE activity much more in GNP‐based system compared to CTAB. Notably, we show a reasonable superiority of SAM‐protected nanoparticles in activating chemical reaction in micromolar concentration of headgroup which certainly boost up application of SAM‐based nanoparticles not only for selective recognition but also as eco‐friendly catalyst. [ABSTRACT FROM AUTHOR]

Background: Carnitine is effective in preventing the accumulation of end products related to lipid peroxidation due to its anti-inflammatory and antioxidant effects. Carnitine also exerts a significant anti-inflammatory role through the downregulation of the nuclear factor kappa beta pathway, which leads to a decrease in the expression of pro-inflammatory cytokines.The aim of the study was to estimate the L-carnitine (L-C) levels in diabetic completely edentulous patients. Materials and Methods: A cross-sectional study was conducted after the selection of 60 samples based on the inclusion and exclusion criteria.The collected saliva samples were utilized to measure the levels of L-C using the sandwich enzyme-linked immunosorbent assay (ELISA) method. One hundred microliters of sample was applied to a particular row of wells and incubated for an hour as part of the sandwich ELISA procedure. After the wells had been cleaned, a second batch of monoclonal L-C was added, and they were once more incubated for an hour. The horseradish peroxidase substrate was then applied after washing the second batch as well. To allow the blue-to-yellow color transition, the wells were kept steady. Following the observation of the color shift, the OD was measured, and the concentration was determined using the sandwich ELISA kit's standard curve as an intercept. The data were statistically analyzed using the independent t-test (significant level P < 0.05) and were tabulated. Results: The L-C levels have higher levels in nondiabetic patients than in diabetic patients. The difference in the baseline mean value between the groups was statistically significant (P = 0.00). Although it is statistically significant (P = 0.00), the mean value for diabetic individuals is 0.19 as opposed to 0.29 for nondiabetic patients. Conclusion: Based on the findings, it can be concluded that L-C improves insulin sensitivity and glucose disposal in diabetic completely edentulous patients. [ABSTRACT FROM AUTHOR]

Herein, we report interactivity and conjugate formation ability between a Zn(II)-metallosurfactant and two clinically relevant serum proteins, albumin (ALB) and γ-globulin (GGB). We found that the surfactant-ALB conjugate promotes coffee ring formation, whereas with GGB it gets suppressed, which is due to the difference in structural anisotropy and hydrophobicity of the conjugates. Additionally, validation of this biosensing platform has been established in human serum samples, and it has potential applications for on-spot rapid diagnostics in remote areas. [ABSTRACT FROM AUTHOR]

Aim: To determine the anti-inflammatory and antimicrobial activity of Glycyrrhiza glabra incorporated in a soft-liner that can be used as denture relining material. Materials and Methods: 3 g of the powdered G. glabra leaves were added to 100 mL of deionized water and filtered after boiling at 100°C for 10 min and the filtrate was boiled until it was reduced to 10 mL. The soft-liner liquid and G. glabra were then blended in proportions of 5 and 10 v/v%, and the mixtures were stirred for 24 h in a closed container. Sample preparation was done for surface roughness, contact angle, and antimicrobial activity: direct Glycyrrhiza solution was taken as a sample for an anti-inflammatory test. A well-diffusion method was performed to determine the antimicrobial effect. Anti-inflammatory activity was determined by inhibition of albumin denaturation assay, wettability through contact angle using a Telescopic Goniometer, surface roughness using a profilometer, and tensile bond strength by using UTM (Instron, ElectroPuls, E3000). All of the groups were compared by doing a one-way analysis of variance, an independent t test was used for comparing two experimental groups. Results: Statistically significant antibacterial property was noted (P <0.05). The maximum concentration of G. glabra’s anti-inflammatory activity was found to be 81% without altering its physical or mechanical properties (P > 0.05). Conclusion: Glycyrrhiza glabra incorporated soft- liner will be a better alternative of conventional softener. [ABSTRACT FROM AUTHOR]