Effect Of Modification Research Articles

Surface modification of titanium implants via PLLA/HA fibrous composite coating to improve piezoelectric properties

Titanium (Ti)-based implants are among the most advantageous biomaterials in both orthopedic and dental applications, owing to their excellent properties and biocompatibility. However, their bioinert surface poses challenges to osteointegrity, raising concerns about implant loosening. The present study examines the effect of surface modification of Ti by applying a bioactive piezoelectric fibrous coating comprised of electrospun poly(L-lactide) (PLLA) as a biodegradable piezopolymer and varying amounts of hydroxyapatite (HA) filler (5−20 wt%) as an osteoconductive piezoceramic. According to SEM micrographs, adding HA increased the fiber diameter, porosity, and pore size of the fibrous structure. Furthermore, peeling test of the fibrous coating demonstrated that applying a polydopamine (PDA) coating before electrospinning onto the Ti substrate effectively enhanced the adhesion strength of the coating. Additionally, the PLLA/HA composite coating exhibited increased piezoelectric properties, with piezoresponse rising from 2.41 ± 0.192 mV/N (5 wt% HA) to 5.42 ± 0.192 mV/N (20 wt% HA). Similarly, PLLA/HA coatings showed superior apatite-forming ability in simulated body fluid (SBF) at 7 and 28 days, with significantly higher calcium-phosphate deposition and a Ca/P ratio close to natural bone, surpassing the neat PLLA coating and bare Ti substrate. Finally, testing with MG-63 cell lines indicated that fibrous composite coatings enhance cell support, demonstrating optimal alkaline phosphatase (ALP) secretion levels and positive cell attachment. Consequently, the surface-modified Ti with fibrous PLLA/HA coating emerges as a promising strategy for the clinical treatment of bone defects.

Loading of antibiotic molecules into organically modified layered calcium silicate

ABSTRACT Calcium silicate is the basic component of bioactive materials that directly bond to living bone (bone-bonding property) in the body environment because calcium silicate can easily form a hydroxyapatite layer on its surface after exposure to body fluids. The organic modification of calcium silicate ceramics is expected to improve their physicochemical properties. Organic modifications of layered inorganic substances have been studied to allow drug loading and sustained release through structural changes. However, few studies have investigated the effect of organic modifications on drug-release carriers. In this study, layered calcium silicate hydrate (C-S-H) prepared via a hydrothermal process was chemically modified with alkyl groups using alkoxysilane. In addition, the loading behavior of the antibiotic levofloxacin was quantitatively analyzed. Structural analysis of the synthesized samples indicated that the interlayer distance and amount of organic content in C-S-H increased with increasing carbon chain length and concentration of alkoxysilane. Levofloxacin was successfully incorporated into the modified C-S-H. It has been suggested that drug incorporation occurs mainly via surface adsorption rather than intercalation into the interlayer.

Microstructure and mechanical properties of multilayer SiC nanofiber paper‐reinforced SiC composites by the NITE method

AbstractIn this work, stacked SiC fibers paper‐reinforced SiC ceramic matrix composites (SiCnf/SiC CMCs) were prepared by nanoimpregnation and transient eutectic (NITE) process using ultra‐long single‐crystal SiC nanofibers. The effect of the SiCnf surface modification via boron nitride (BN) interphase deposition as well as the sintering additive (Al2O3–Y2O3) content on the density, microstructure, and mechanical properties of SiCnf/SiC CMCs has been investigated systematically. The results revealed that the laminated SiCnf/SiC CMCs feature a significant saw‐tooth‐like curve on the load–displacement test, which indicates that the obtained laminated structure with the weak interlayer binding owning to the BN coating treatment possesses significant toughening to the SiC ceramics. Specifically, the SiCnf/SiC CMCs with the sintering additive content of 12 wt% revealed a fracture toughness of over 10 MPa m1/2 after 60 min of BN interface deposition, which is 104.31% higher than that of the composites prepared without BN coating.

Experimental Study of Condensation Heat Transfer and Droplet Dynamics on Multiple Horizontal Copper Tubes with Superhydrophobic Characteristics

We conducted an experimental study on the condensation heat transfer and droplet dynamics on multiple horizontal copper tubes with superhydrophobic characteristics. Condensation heat transfer has various industrial applications such as power plants and air-conditioning systems. Because condensers are typically designed in multiple-tube configurations, studying the phenomenon of multiple tubes is important. We investigated the effect of a superhydrophobic surface modification, which induces dropwise condensation, on the heat transfer performance of multiple-tube condensers. The purpose of this research is to evaluate the extent to which heat transfer performance is improved by comparing superhydrophobic tubes with bare tubes and to analyze the impact of droplet dynamics on heat transfer performance. The results show that the heat transfer coefficient of the superhydrophobic tubes is improved by approximately 9.5%–44.9% compared to that of bare tubes. Droplet dynamic analysis revealed differences in droplet behavior between the superhydrophobic tubes and bare tubes, including the formation of droplets by condensation, the process of droplets falling on the tube surface, and the impact of droplets falling on other tubes in a multiple-tube configuration. Based on these results and observations, it can be concluded that the heat transfer performance of the superhydrophobic tube is superior to that of the bare tube. The droplet dynamic analysis demonstrated that the droplets formed on the superhydrophobic surface could be easily removed by the flow, leading to more efficient heat transfer. These findings highlight the potential for more efficient heat transfer in multiple tubes through superhydrophobic modifications.

Realization of Atomically Uniform ALD-Al2O3 and TiO2 on SiO2 and GeO2 by UV-Ozone Treatment

Thermally oxidized SiO2/Si and GeO2/Ge are difficult to form very thin oxide films by atomic layer deposition (ALD) due to the chemical inertness of the oxide film surface. In this study, the effect of surface modification of insulating films by the UV-Ozone (UVO) method on ALD was investigated with the aim of controlling the atomic layer thickness and producing a uniform oxide film. The results show that UVO treatment can deposit atomic layer-thick films on SiO2 or GeO2 without delay. This may be due to the formation of dangling bonds on the oxide film surface, which improves the reactivity between the surface and the precursor during initial layer formation.

Quantitative characterization of 3D pore structures and percolation characteristics in bioturbated reservoir media based on X-ray micro-CT: a case study of the Neogene Sanya Formation in the Qiongdongnan Basin, Northern South China Sea

Organisms alter the primary texture of sediments, leading to alteration in petrophysical properties mediated by a textural and mineralogical contrast between burrow-fill and sediment host, which affects reservoir properties and fluid flow characteristics. In this article, in order to understand the microscopic pore structure and flow state of fluids in microscopic pores of bioturbated reservoirs, Ophiomorpha-bearing bioturbated reservoirs in the Neogene Sanya Formation of the Qiongdongnan Basin in the northern South China Sea were selected to research. Micro-CT was applied to scan selected core plugs, and a 3D pore structure model was established. The geometric characteristics of the microscopic pore structure were quantitatively and visually characterized by a modified maximal ball algorithm, and connectivity analysis of the pore structure was carried out. Numerical simulations of the percolation characteristics of the analyzed bioturbated reservoir samples were performed using digital core software (Avizo) and multi-physics field simulation software (Comsol). The results show that: (1) 3D pore structures reveal that pore volume, pore area, pore equivalent radius, throat area, throat equivalent radius and throat length have a large distribution range; among them, the pore volume has the largest distribution range, which can vary by six orders of magnitude, indicating that the pore size distribution of the bioturbated reservoir is uneven and has strong heterogeneous characteristics; (2) the connected pore structure is very complex, and as the equivalent radius of connected pore increases, the coordination number also gradually increases, the better the connectivity. Numerical percolation simulation results also suggested that larger connected pore space plays a key role in the effective permeability of the reservoir. This study has important implications for analyzing the modification effect of bioturbation on oil and gas reservoirs, and enhancing production and recovery in the study area.

Optimization Mechanism of Mechanical Properties of Basalt Fiber-Epoxy Resin Composites by Interfacially Enriched Distribution of Nano-Starch Crystals

Fibre reinforced polymer composites have become a new generation of structural materials due to their unique advantages such as high specific strength, designability, good dimensional stability and ease of large-area monolithic forming. However, the problem of interfacial bonding between the resin matrix and the fibres limits the direct use of reinforcing fibres and has become a central difficulty in the development of basalt fibre-epoxy composites. This paper proposes a solution for enhancing the strength of the fibre-resin interface using maize starch nanocrystals, which are highly yield and eco-friendly. Firstly, in this paper, corn starch nanocrystals (SNC) were prepared by hydrolysis, and were deposited on the surface of basalt fibers by electrostatic adsorption. After that, in order to maximize the modification effect of nano-starch crystals on the interface, the basalt fiber-epoxy resin composite samples were prepared by mixing in a pressureless molding method. The test results shown that the addition of basalt fibers alone led to a reduction in the strength of the sample. Deposition of 0.1 wt% SNC on the surface of basalt fibers can make the strength consistent with pure epoxy resin. When the adsorption amount of SNC reached 0.5 wt%, the tensile strength of the samples was 23.7% higher than that of pure epoxy resin. This is due to the formation of ether bond homopolymers between the SNC at the fibre-epoxy interface and the epoxy resin, which distorts the originally smooth interface, leading to increased stress concentration and the development of cracks. This enhances the binding of basalt fibers. The conclusions of this paper can provide an effective, simple, low-cost and non-polluting method of interfacial enhancement modification.

Practical Technology of Toughening Epoxy Resin (II): Modification Effects of Special Engineering Plastics on Epoxy Resin

The effects of Special engineering plastics (SEP) such as polyether ether ketone (PEEK), polyimide (PI), thermoplastic polyimide (TPI), polyphenylene sulfide (PPS), polysulfone (PSF), liquid crystal polymer (LCP), polyaromatic (PAR) on the mechanical, thermal and electrical properties of epoxy resins were studied in this paper. The engineering plastics with rigid and active elements produce differential phase in the epoxy curing process, which can absorb energy under stress, prevent micro-crack diffusion, and improve the mechanical properties of epoxy resin, including tensile, compression and impact strength. SEP with better heat resistance than epoxy resins are beneficial for improving the heat resistance of epoxy resins. During the epoxy curing process, strong intermolecular forces are generated between SEP and epoxy resin, which further enhances the heat resistance of modified epoxy resins. Better insulation of epoxy resin are achieved by adding engineering plastics with fine insulation equipment. PSF with poor dispersion aggregates to form a weak interface layer, which first fails under stress, and its main mechanical properties slightly decrease. The dispersion of pulp like LCP in epoxy resin is poor, and there is no significant improvement in the mechanical properties of epoxy resin. PAR are difficult to form a homogeneous phase in epoxy resin and cannot be used for epoxy resin modification research.

AsteRIa enables robust interaction modeling between chromatin modifications and epigenetic readers.

Chromatin, the nucleoprotein complex consisting of DNA and histone proteins, plays a crucial role in regulating gene expression by controlling access to DNA. Chromatin modifications are key players in this regulation, as they help to orchestrate DNA transcription, replication, and repair. These modifications recruit epigenetic 'reader' proteins, which mediate downstream events. Most modifications occur in distinctive combinations within a nucleosome, suggesting that epigenetic information can be encoded in combinatorial chromatin modifications. A detailed understanding of how multiple modifications cooperate in recruiting such proteins has, however, remained largely elusive. Here, we integrate nucleosome affinity purification data with high-throughput quantitative proteomics and hierarchical interaction modeling to estimate combinatorial effects of chromatin modifications on protein recruitment. This is facilitated by the computational workflow asteRIa which combines hierarchical interaction modeling, stability-based model selection, and replicate-consistency checks for astable estimation of Robust Interactions among chromatin modifications. asteRIa identifies several epigenetic reader candidates responding to specific interactions between chromatin modifications. For the polycomb protein CBX8, we independently validate our results using genome-wide ChIP-Seq and bisulphite sequencingdatasets. We provide the first quantitative framework for identifying cooperative effects of chromatin modifications on protein binding.

The Functions of N-methyladenosine (m6A) Modification on HIV-1 mRNA.

In recent years, there has been a growing interest in the study of RNA modifications, with some researchers focusing specifically on the connection between these modifications and viruses, as well as the impact they have on viral mRNA and its functionality. The most common type of RNA chemical modification is m6A, which involves the addition of a methyl group covalently to the N6 position of adenosine. It is a widely observed and evolutionarily conserved RNA modification. The regulation of m6A modification primarily involves methyltransferases (writers) and demethylases (erasers) and is mediated by m6A-binding proteins (readers). In HIV-1, m6A sites are predominantly located in the 5' untranslated region (5'UTR) and 3' untranslated region (3'UTR). Additionally, m6A modifications are also present in the RRE RNA of HIV-1. This review provides a detailed account of the effects of these m6A modifications on HIV-1 functionality.

Differential Effects of Post-translational Modifications on the Membrane Interaction of Huntingtin Protein.

Huntington's disease is a neurodegenerative disorder caused by an expanded polyglutamine stretch near the N-terminus of the huntingtin (HTT) protein, rendering the protein more prone to aggregate. The first 17 residues in HTT (Nt17) interact with lipid membranes and harbor multiple post-translational modifications (PTMs) that can modulate HTT conformation and aggregation. In this study, we used a combination of biophysical studies and molecular simulations to investigate the effect of PTMs on the helicity of Nt17 in the presence of various lipid membranes. We demonstrate that anionic lipids such as PI4P, PI(4,5)P2, and GM1 significantly enhance the helical structure of unmodified Nt17. This effect is attenuated by single acetylation events at K6, K9, or K15, whereas tri-acetylation at these sites abolishes Nt17-membrane interaction. Similarly, single phosphorylation at S13 and S16 decreased but did not abolish the POPG and PIP2-induced helicity, while dual phosphorylation at these sites markedly diminished Nt17 helicity, regardless of lipid composition. The helicity of Nt17 with phosphorylation at T3 is insensitive to the membrane environment. Oxidation at M8 variably affects membrane-induced helicity, highlighting a lipid-dependent modulation of the Nt17 structure. Altogether, our findings reveal differential effects of PTMs and crosstalks between PTMs on membrane interaction and conformation of HTT. Intriguingly, the effects of phosphorylation at T3 or single acetylation at K6, K9, and K15 on Nt17 conformation in the presence of certain membranes do not mirror that observed in the absence of membranes. Our studies provide novel insights into the complex relationship between Nt17 structure, PTMs, and membrane binding.

Systematic Review of Genetic Modifiers Associated with the Development and/or Progression of Nephropathy in Patients with Sickle Cell Disease.

Sickle cell nephropathy (SCN) is a common complication of sickle cell disease (SCD) that significantly contributes to morbidity and mortality. In addition to clinical and life-style factors, genetic variants influence this risk. We performed a systematic review, searching five databases. Studies evaluating the effect of genetic modifiers on SCN were eligible. Twenty-eight studies (fair-to-good quality) were included: one genome-wide association study, twenty-six case-control studies, and one article combining both approaches. APOL1 was significantly associated with albuminuria and hyperfiltration in children and with worse glomerular filtration in adults. On the other hand, alpha-thalassemia protected patients against albuminuria and hyperfiltration, while BCL11A variants were protective against albuminuria alone. The HMOX1 long GT-tandem repeat polymorphism led to a lower glomerular filtration rate. No modifiers for the risk of hyposthenuria were identified. A genome-wide association approach identified three new loci for proteinuria (CRYL1, VWF, and ADAMTS7) and nine loci were linked with eGFR (PKD1L2, TOR2A, CUBN, AGGF1, CYP4B1, CD163, LRP1B, linc02288, and FPGT-TNNI3K/TNNI3K). In conclusion, this systematic review supports the role of genetic modifiers in influencing the risk and progression of SCN. Incorporating and expanding this knowledge is crucial to improving the management and clinical outcomes of patients at risk.

Addition of Cyperus esculentus (tiger nut) milk improved the flavor and gelation properties of set yogurt: The main contribution of volatile constituents, starch and proteins

The modification effects of Cyperus esculentus milk (CEM) on the sensory and gel properties of set yogurt were elucidated in this study. It was found that a suitable CEM addition adjusted the color, moderated the acidity, and enriched the aroma of compound yogurt. Interestingly, the internal network structures of yogurt gel were strengthened at a low CEM addition, causing the improvement of yogurt textural properties, viscoelasticity and water-holding-capacity. However, a high CEM addition induced the incompact gel structures, unbeneficial to the expected textures and rheology of compound yogurt. Then, starch (CES) and proteins (CEP) were isolated to elucidate their influence on the gelation behaviors of casein. The results showed that CES always promoted the formation of CES-casein gel, improving its textural, elastic and morphological characters. This resulted from the presence of branchy side chains of amylopectin and the viscosity of starch molecules, making CES tightly anchor with casein gel and thus fill in the gel pores. However, the CEP-casein gel properties described an enhanced-weakened trend with CEP addition increasing. Notably, at a low addition, CEP well-dispersed and interacted with casein, filling into gel pores and thus strengthening gel network, while at a high addition, the self-gelling CEP gradually separated from casein gel due to few branchy structures and insufficient viscosity. It was the characteristic behaviors of CEM components that affected the gelling properties of compound yogurt. Conclusively, a moderate addition of CEM (<20%) is recommended to enrich the flavor of set yogurt with simultaneously-improved or maintained textural and gelling properties.

The protective effect of dietary folate intake on gastric cancer is modified by alcohol consumption: A pooled analysis of the StoP Consortium.

Dietary folate intake has been identified as a potentially modifiable factor of gastric cancer (GC) risk, although the evidence is still inconsistent. We evaluate the association between dietary folate intake and the risk of GC as well as the potential modification effect of alcohol consumption. We pooled data for 2829 histologically confirmed GC cases and 8141 controls from 11 case-control studies from the international Stomach Cancer Pooling Consortium. Dietary folate intake was estimated using food frequency questionnaires. We used linear mixed models with random intercepts for each study to calculate adjusted odds ratios (OR) and 95% confidence interval (CI). Higher folate intake was associated with a lower risk of GC, although this association was not observed among participants who consumed >2.0 alcoholic drinks/day. The OR for the highest quartile of folate intake, compared with the lowest quartile, was 0.78 (95% CI, 0.67-0.90, P-trend = 0.0002). The OR per each quartile increment was 0.92 (95% CI, 0.87-0.96) and, per every 100 μg/day of folate intake, was 0.89 (95% CI, 0.84-0.95). There was a significant interaction between folate intake and alcohol consumption (P-interaction = 0.02). The lower risk of GC associated with higher folate intake was not observed in participants who consumed >2.0 drinks per day, ORQ4v Q1 = 1.15 (95% CI, 0.85-1.56), and the OR100 μg/day = 1.02 (95% CI, 0.92-1.15). Our study supports a beneficial effect of folate intake on GC risk, although the consumption of >2.0 alcoholic drinks/day counteracts this beneficial effect.

Dorsal root ganglion-derived exosomes deteriorate neuropathic pain by activating microglia via the microRNA-16-5p/HECTD1/HSP90 axis

BackgroundThe activated microglia have been reported as pillar factors in neuropathic pain (NP) pathology, but the molecules driving pain-inducible microglial activation require further exploration. In this study, we investigated the effect of dorsal root ganglion (DRG)-derived exosomes (Exo) on microglial activation and the related mechanism.MethodsA mouse model of NP was generated by spinal nerve ligation (SNL), and DRG-derived Exo were extracted. The effects of DRG-Exo on NP and microglial activation in SNL mice were evaluated using behavioral tests, HE staining, immunofluorescence, and western blot. Next, the differentially enriched microRNAs (miRNAs) in DRG-Exo-treated microglia were analyzed using microarrays. RT-qPCR, RNA pull-down, dual-luciferase reporter assay, and immunofluorescence were conducted to verify the binding relation between miR-16-5p and HECTD1. Finally, the effects of ubiquitination modification of HSP90 by HECTD1 on NP progression and microglial activation were investigated by Co-IP, western blot, immunofluorescence assays, and rescue experiments.ResultsDRG-Exo aggravated NP resulting from SNL in mice, promoted the activation of microglia in DRG, and increased neuroinflammation. miR-16-5p knockdown in DRG-Exo alleviated the stimulating effects of DRG-Exo on NP and microglial activation. DRG-Exo regulated the ubiquitination of HSP90 through the interaction between miR-16-5p and HECTD1. Ubiquitination alteration of HSP90 was involved in microglial activation during NP.ConclusionsmiR-16-5p shuttled by DRG-Exo regulated the ubiquitination of HSP90 by interacting with HECTD1, thereby contributing to the microglial activation in NP.

A review on sustainable management of biomass: physicochemical modification and its application for the removal of recalcitrant pollutants-challenges, opportunities, and future directions.

Adsorption is one of the most efficient methods for remediating industrial recalcitrant wastewater due to its simple design and low investment cost. However, the conventional adsorbents used in adsorption have several limitations, including high cost, low removal rates, secondary waste generation, and low regeneration ability. Hence, the focus of the research has shifted to developing alternative low-cost green adsorbents from renewable resources such as biomass. In this regard, the recent progress in the modification of biomass-derived adsorbents, which are rich in cellulosic content, through a variety of techniques, including chemical, physical, and thermal processes, has been critically reviewed in this paper. In addition, the practical applications of raw and modified biomass-based adsorbents for the treatment of industrial wastewater are discussed extensively. In a nutshell, the adsorption mechanism, particularly for real wastewater, and the effects of various modifications on biomass-based adsorbents have yet to be thoroughly studied, despite the extensive research efforts devoted to their innovation. Therefore, this review provides insight into future research needed in wastewater treatment utilizing biomass-based adsorbents, as well as the possibility of commercializing biomass-based adsorbents into viable products.

Synthesis, characterisation and application of organic and inorganic bentonite for the removal of gentian violet

ABSTRACT The intensive use of dyes in industry has caused serious pollution problems, due to industrial wastewater discharges. It is well known that dyes have harmful effects on humans, animals, and other living beings. Therefore, the treatment of industrial wastewater before its release into the environment requires great attention. This work is devoted to the study of the effect of organic modifications by DMSO and/or CTAB and an inorganic modification by spinel oxide ZnCr2O4 on the structural and textural properties of local clay (M’Zila bentonite). The materials resulting from these modifications are used as adsorbents for a cationic dye such as gentian violet. These materials were synthesised and characterised by XRD, FTIR, BET and SEM. These analyzes confirmed the considerable changes in the structure of the clays modified by DMSO and/or CTAB- ZnCr2O4, the formation of pillared bentonites and the increase in the basal spacing’s of the modified clays by 15.05 Å for the bentonite of M’Zila at 23.80 Å for bentonite-CTAB-ZnCr2O4 (BCZnCr), at 27.37 Å for bentonite-DMSO-ZnCr2O4 (BDZnCr) and at 25.89 Å for bentonite-DMSO-CTAB-ZnCr2O4 (BDCZnCr).These modifications produced a rougher and more porous surface, resulting in a significant increase in the specific surface area from 60.13 m2 g−1 for sodium bentonite to 104.63 m2 g−1 for BCZnCr and 104.59 m2 g−1 for BDCZnCr. The adsorption of gentian violet was carried out under the following conditions: solid liquid ratio: 1 g/L, pH = 10 and contact time at equilibrium 1 h. The adsorption kinetics perfectly follows the pseudo second order model as well as that of intraparticle diffusion for all materials. The isotherms are of type S; they are well described by the Langmuir-Freundlich model. The thermodynamic parameters indicate that the physisorption of gentian violet by the different materials is spontaneous, exothermic, and disordered.

Polarity control of siloxane composite films for triboelectric nanogenerator based self-powered body temperature monitoring

Body temperature monitoring systems serve as key indicators for identifying potential patients with various illnesses such as influenza and COVID-19. Conventionally, these monitoring devices rely on batteries, limiting their long-term and widespread application. Self-powered thermometers are considered a sustainable solution that enable continuous monitoring. Among various self-charging power sources, triboelectric nanogenerators (TENGs) are a novel development, but suffer several critical drawbacks for medical applications. In this study, we present a high-performance TENG for self-powered body temperature monitoring systems by controlling the polarity of glass-fabric reinforced vinyl-thiol functionalized hybrid materials (GFR-VTHs) by varying the phenyl group contents. The effect of polarity modification on the performance of the developed TENG was confirmed by the high electrical output and stable operation under 10,000 cycles of repetitive pressing tests. Finally, self-powered body temperature monitoring systems were constructed by measuring human body temperature with a clinical thermometer powered by the GFR-VTH-based TENG, demonstrating device feasibility as a power source for self-powered healthcare systems.

Reading and Writing the Ubiquitin Code Using Genetic Code Expansion.

Deciphering ubiquitin proteoform signaling and its role in disease has been a long-standing challenge in the field. The effects of ubiquitin modifications, its relation to ubiquitin-related machineries, and its signaling output has been particularly limited by its reconstitution and means of characterization. Advances in genetic code expansion have contributed towards addressing these challenges by precision incorporation of unnatural amino acids through site selective codon suppression. This review discusses recent advances in studying the 'writers', 'readers', and 'erasers' of the ubiquitin code using genetic code expansion. Highlighting strategies towards genetically encoded protein ubiquitination, ubiquitin phosphorylation, acylation, and finally surveying ubiquitin interactions, we strive to bring attention to this unique approach towards addressing a widespread proteoform problem.

Assessment of the Effect of Surface Modification of Metal Oxides on Silver Nanoparticles: Optical Properties and Potential Toxicity.

Silver nanoparticles (AgNPs) have garnered significant interest due to their distinctive properties and potential applications. Traditional fabrication methods for nanoparticles often involve high-energy physical conditions and the use of toxic solvents. Various green synthesis approaches have been developed to circumvent these issues and produce environmentally benign nanoparticles. Our study focuses on the green synthesis of AgNPs using L-ascorbic acid and explores the modification of their properties to enhance antibacterial and anticancer effects. This is achieved by coating the nanoparticles with Zinc oxide (ZnO) and Silica oxide (SiO2), which alters their optical properties in the visible spectrum. The synthesized formulations-AgNPs, zinc oxide-silver nanoparticles (Ag@ZnO), and silica oxide-silver nanoparticles (Ag@SiO2) core/shell nanoparticles-were characterized using a suite of physicochemical techniques, including Transmission Electron Microscopy (TEM), Dynamic Light Scattering (DLS), Zeta potential measurement, UV-Vis spectroscopy, Refractive Index Measurements, and Optical Anisotropy Assessment. TEM imaging revealed particle sizes of 11 nm for AgNPs, 8 nm for Ag@ZnO, and 400 nm for Ag@SiO2. The Zeta potential values for Ag@ZnO and Ag@SiO2 were measured at -17.0 ± 5 mV and -65.0 ± 8 mV, respectively. UV-Vis absorption spectra were recorded for all formulations in the 320 nm to 600 nm wavelength range. The refractive index of AgNPs at 404.7 nm was 1.34572, with slight shifts observed for Ag@ZnO and Ag@SiO2 to 1.34326 and 1.37378, respectively. The cytotoxicity of the nanocomposites against breast cancer cell lines (MCF-7) was assessed using the MTT assay. The results indicated that AgNPs and Ag@ZnO exhibited potent therapeutic effects, with IC50 values of 494.00 µg/mL and 430.00 µg/mL, respectively, compared to 4247.20 µg/mL for Ag@SiO2. Additionally, the antibacterial efficacy of AgNPs was significantly enhanced under visible light irradiation. Ag@ZnO demonstrated substantial antibacterial activity both with and without light exposure, while the Ag@SiO2 nanocomposites significantly reduced the inherent antibacterial activity of silver. Conversely, the Ag@ZnO nanocomposites displayed pronounced antibacterial and anticancer activities. The findings suggest that silver-based nanocomposites, particularly Ag@ZnO, could be practical tools in water treatment and the pharmaceutical industry due to their enhanced therapeutic properties.