Three-dimensional printing technologies are becoming increasingly attractive for their versatility; the geometrical customizability and manageability of the final product properties are the key points. This work aims to assess the feasibility of producing radiopaque filaments for fused deposition modeling (FDM), a 3D printing technology, starting with zinc oxide (ZnO) and polylactic acid (PLA) as the raw materials. Indeed, ZnO and PLA are promising materials due to their non-toxic and biocompatible nature. Pellets of PLA and ZnO in the form of nanoparticles were mixed together using ethanol; this homogenous mixture was processed by a commercial extruder, optimizing the process parameters for obtaining mechanically stable samples. Scanning electron microscopy analyses were used to assess, in the extruded samples, the homogenous distribution of the ZnO in the PLA matrix. Moreover, X-ray microtomography revealed a certain homogenous radiopacity; this imaging technique also confirmed the correct distribution of the ZnO in the PLA matrix. Thus, our tests showed that mechanically stable radiopaque filaments, ready for FDM systems, were obtained by homogenously loading the PLA with a maximum ZnO content of 6.5% wt. (nominal). This study produced multiple outcomes. We demonstrated the feasibility of producing radiopaque filaments for additive manufacturing using safe materials. Moreover, each phase of the process is cost-effective and green-oriented; in fact, the homogenous mixture of PLA and ZnO requires only a small amount of ethanol, which evaporates in minutes without any temperature adjustment. Finally, both the extruding and the FDM technologies are the most accessible systems for the additive manufacturing commercial apparatuses.

Functional characterization of enzymes/proteins requires determination of the binding affinity of small molecules or other biomolecules with the target proteins. Several available techniques, such as proteomics and drug discovery strategies, require a precise and high-throughput assay for rapid and reliable screening of potential candidates for further testing. Surface plasmon resonance (SPR), a well-established label-free technique, directly measures biomolecular affinities. SPR assays require immobilization of one interacting component (ligand) on a conductive metal (mostly gold or silver) and a continuous flow of solution containing potential binding partner (analyte) across the surface. The SPR phenomenon occurs when polarized light excites the electrons at the interface of the metal and the dielectric medium to generate electromagnetic waves that propagate parallel to the surface. Changes in the refractive index due to interaction between the ligand and analyte are measured by detecting the reflected light, providing real-time data on kinetics and specificity. A prominent use of SPR is identifying compounds in crude plant extracts that bind to specific molecules. Procedures that utilize SPR are becoming increasingly applicable outside the laboratory setting, and SPR imaging and localized SPR (LSPR) are cheaper and more portable alternative for in situ detection of plant or mammalian pathogens and drug discovery studies. LSPR, in particular, has the advantage of direct attachment to test tissues in live-plant studies. Here, we describe three protocols utilizing SPR-based assays for precise analysis of protein-ligand interactions. © 2024 Wiley Periodicals LLC. Basic Protocol 1: SPR comparison of binding affinities of viral reverse transcriptase polymorphisms Basic Protocol 2: SPR screening of crude plant extract for protein-binding agents Basic Protocol 3: Localized SPR-based antigen detection using antibody-conjugated gold nanoparticles.

BACKGROUND: Acinetobacter baumannii resistant strains lead to increased mortality, treatment costs, and an increase in the length of hospitalization. Nowadays, nanoparticles are considered a substitute for antibiotics. This study aimed to determine the MIC of Silver (Ag) and Zinc Oxide (ZnO) Nanoparticles (NPs) on Biofilm-Producing Acinetobacter baumannii and determine the relationship between MIC and frequency of efflux pump genes in cutaneous specimens in Shiraz, Southwest Iran in 2021-2022.
METHODS: In this study, specimens were collected from April 2021 to June 2022 at Namazi and Faqihi Hospitals in Shiraz. Investigation of biofilm production in multidrug resistance (MDR) isolates was done by the microtiter plate method. Synthesized nanoparticles were characterized by UV-vis spectrum, X-ray diffraction (XRD), and electron microscopy. The MIC of AgNPs and ZnONPs for isolates was done using the method described in the CLSI guideline (2018). The antibacterial effect of MIC of NPs on inanimate objects was done by colony counts. The prevalence of efflux pump genes (adeR, adeC, adeA, abeM, adeK, adeI) was also investigated by PCR technique.
RESULTS: The highest ceftriaxone resistance (68%) and lowest colistin resistance (7%) were identified. 57% of isolates were MDR. In addition, 71.9% could produce biofilm and 28.1% of isolates could not produce biofilm. The average size of AgNPs and ZnONPs in the present study is 48 and < 70 nm, respectively. The nanoparticles were spherical. The MIC and the MBC of the ZnONPs were in the range of 125 to 250 µg/mL respectively. Also, for AgNPs, the MIC and the MBC were in the range of 62.5 to 250 µg/ml, respectively. AbeM gene had the highest frequency and the AdeK gene had the lowest frequency. Statistical analysis showed that there is a relationship between the frequency of adeA, adeC, and adeM genes with the MIC of AgNPs and ZnONPs.
CONCLUSIONS: According to the results of the present study, inanimate objects such as scalpels in contact with AgNPs (6000 µg/ml for 240 min) or ZnONPs (5000 µg/ml for 120 min) can be free of biofilm producing Acinetobacter baumannii  with efflux pump genes.

This study aimed to develop a novel Gelatin silver oxide material for releasing nitric oxide bionanocomposite wound dressing with enhanced mechanical, chemical, and antibacterial properties for the treatment of diabetic wounds. The gelatin- silver oxide nanoparticles (Ag2O-NP) bio nanocomposite was prepared using chitosan and gelatin polymers incorporated with silver oxide nanoparticles through the freeze-drying method. The samples were characterized using scanning electron microscopy (SEM) and X-ray diffraction (XRD) analysis. Results showed that the Ag2O-NP nanoparticles increased porosity, decreased pore size, and improved elastic modulus. The Ag2O-NP wound dressing exhibited the most effective antibacterial properties against Staphylococcus aureus and Escherichia coli. Among the samples, the wound dressing containing silver oxide nanoparticles demonstrated superior physical and mechanical properties, with 48% porosity, a tensile strength of 3.2 MPa, and an elastic modulus of 51.7 MPa. The fabricated wound dressings had a volume ratio of empty space to total volume ranging from 40% to 60%. In parallel, considering the complications of diabetes and its impact on the vascular system, another aspect of the research focused on developing a per2mediated wound dressing capable of releasing nitric oxide gas to regenerate damaged vessels and accelerate diabetic wound healing. Chitosan, a biocompatible and biodegradable polymer, was selected as the substrate for the wound dressing, and beta-glycerophosphate (GPβ), tripolyphosphate (TPP), and per2mediated alginate (AL) were used as crosslinkers. The chitosan-alginate (CS-AL) wound dressing exhibited optimal characteristics in terms of hole count and uniformity in the scanning electron microscope test. It also demonstrated superior water absorption (3854%) and minimal air permeability. Furthermore, the CS-AL sample exhibited an 80% degradation rate after 14 days, indicating its suitability as a wound dressing. The wound dressing was loaded with S-nitrosoglutathione (GSNO) powder, and the successful release of nitric oxide gas was confirmed through the grease test, showing a peak at a wavelength of 540 nm. Subsequent investigations revealed that the treatment of human umbilical vein endothelial cells (HUVECs) with high glucose led to a decrease in the expression of PER2 and SIRT1, while the expression of PER2 increased, which may subsequently enhance the expression of SIRT1 and promote cell proliferation activity. However, upon treatment of the cells with the modified materials, an increase in the expression of PER2 and SIRT1 was observed, resulting in a partial restoration of cell proliferative activity. This comprehensive study successfully developed per2-mediated bio-nanocomposite wound dressings with improved physical, mechanical, chemical, and antibacterial properties. The incorporation of silver oxide nanoparticles enhanced the antimicrobial activity, while the released nitric oxide gas from the dressing demonstrated the ability to mitigate vascular endothelial cell damage induced by high glucose levels. These advancements show promising potential for facilitating the healing process of diabetic wounds by addressing complications associated with diabetes and enhancing overall wound healing.

UNASSIGNED: Regadenoson, an agonist of adenosine A2 receptors, enables transient blood-brain barrier (BBB) disruption. The relevance of regadenoson as a pharmacological strategy for brain delivery was investigated using in vivo PET imaging in rats.
UNASSIGNED: Kinetic modeling of brain PET data was performed to estimate the impact of regadenoson (0.05 mg.kg-1, i.v.) on BBB permeation compared with control rats (n = 4-6 per group). Three radiolabeled compounds of different sizes, which do not cross the intact BBB, were tested.
UNASSIGNED: Regadenoson significantly increased the BBB penetration (+116 ± 13%, p < 0.001) of [18F]2-deoxy-2-fluoro-D-sorbitol ([18F]FDS, MW = 183 Da), a small-molecule marker of BBB permeability. The magnitude of the effect was different across brain regions, with a maximum increase in the striatum. Recovery of BBB integrity was observed 30 min after regadenoson injection. Regadenoson also increased the brain penetration (+72 ± 45%, p < 0.05) of a radiolabeled nanoparticle [89Zr]AGuIX (MW = 9 kDa). However, the brain kinetics of a monoclonal antibody ([89Zr]mAb, MW = 150 kDa) remained unchanged (p > 0.05).
UNASSIGNED: PET imaging showed the features and limitations of BBB disruption induced by regadenoson in terms of extent, regional distribution, and reversibility. Nevertheless, regadenoson enables the brain delivery of small molecules or nanoparticles in rats.

OBJECTIVE: TLD-1 is a novel pegylated liposomal doxorubicin (PLD) formulation aiming to optimise the PLD efficacy-toxicity ratio. We aimed to characterise TLD-1\'s population pharmacokinetics using non-compartmental analysis and nonlinear mixed-effects modelling.
METHODS: The PK of TLD-1 was analysed by performing a non-compartmental analysis of longitudinal doxorubicin plasma concentration measurements obtained from a clinical trial in 30 patients with advanced solid tumours across a 4.5-fold dose range. Furthermore, a joint parent-metabolite PK model of doxorubicinentrapped, doxorubicinfree, and metabolite doxorubicinol was developed. Interindividual and interoccasion variability around the typical PK parameters and potential covariates to explain parts of this variability were explored.
RESULTS: Medians  ± standard deviations of dose-normalised doxorubicinentrapped+free Cmax and AUC0-∞ were 0.342 ± 0.134 mg/L and 40.1 ± 18.9 mg·h/L, respectively. The median half-life (95 h) was 23.5 h longer than the half-life of currently marketed PLD. The novel joint parent-metabolite model comprised a one-compartment model with linear release (doxorubicinentrapped), a two-compartment model with linear elimination (doxorubicinfree), and a one-compartment model with linear elimination for doxorubicinol. Body surface area on the volumes of distribution for free doxorubicin was the only significant covariate.
CONCLUSIONS: The population PK of TLD-1, including its release and main metabolite, were successfully characterised using non-compartmental and compartmental analyses. Based on its long half-life, TLD-1 presents a promising candidate for further clinical development. The PK characteristics form the basis to investigate TLD-1 exposure-response (i.e., clinical efficacy) and exposure-toxicity relationships in the future. Once such relationships have been established, the developed population PK model can be further used in model-informed precision dosing strategies.
BACKGROUND: ClinicalTrials.gov-NCT03387917-January 2, 2018.

The intended research aims to explore the convection phenomena of a hybrid nanofluid composed of gold and silver nanoparticles. This research is novel and significant because there is a lack of existing studies on the flow behavior of hybrid nanoparticles with important physical properties of blood base fluids, especially in the case of sidewall ruptured dilated arteries. The implementation of combined nanoparticles rather than unadulterated nanoparticles is one of the most crucial elements in boosting the thermal conduction of fluids. The research methodology encompasses the utilization of advanced bio-fluid dynamics software for simulating the flow of the nanofluid. The physical context elucidates the governing equations of momentum, mass, momentum, and energy in terms of partial differential equations. The results are displayed in both tabular and graphical forms to demonstrate the numerical and graphical solutions. The effect of physical parameters on velocity distribution is illustrated through graphs. Furthermore, the study\'s findings are unique and original, and these computational discoveries have not been published by any researcher before. The finding implies that utilizing hybrid nanoparticles as drug carriers holds great promise in mitigating the effects of blood flow, potentially enhancing drug delivery, and minimizing its impact on the body.

Ecological risk of micro/nano-plastics (MPs/NPs) has become an important environmental issue. Microcystin-leucine-arginine (MC-LR) produced by Microcystis aeruginosa (M. aeruginosa) is the most common and toxic secondary metabolites (SM). However, the influencing mechanism of MPs and NPs exposure on MC-LR synthesis and release have still not been clearly evaluated. In this work, under both acute (4d) and long-term exposure (10d), only high-concentration (10 mg/L) exposure of amino-modified polystyrene NPs (PS-NH2-NPs) promoted MC-LR synthesis (32.94 % and 42.42 %) and release (27.35 % and 31.52 %), respectively. Mechanistically, PS-NH2-NPs inhibited algae cell density, interrupted pigment synthesis, weakened photosynthesis efficiency, and induced oxidative stress, with subsequent enhancing the MC-LR synthesis. Additionally, PS-NH2-NPs exposure up-regulated MC-LR synthesis pathway genes (mcyA, mcyB, mcyD, and mcyG) combined with significantly increased metabolomics (Leucine and Arginine), thereby enhancing MC-LR synthesis. PS-NH2-NPs exposure enhanced the MC-LR release from M. aeruginosa via up-regulated MC-LR transport pathway genes (mcyH) and the shrinkage of plasma membrane. Our results provide new insights into the long-time coexistence of NPs with algae in freshwater systems might pose a potential threat to aquatic environments and human health.

UNASSIGNED: The purpose of this comparative study in vitro was to evaluate the effect of organic and inorganic nanoparticles on colour stability, tear strength and hardness of maxillofacial silicone elastomer at baseline and when subjected to outdoor weathering for 6 months.
UNASSIGNED: A total of 240 specimens were fabricated using M511 platinum silicone which were divided into total 4 groups (n = 60) based on the type of nanoparticles (control, polytetrafuoroethylene [PTFE], titanium dioxide [TiO2], zinc oxide [ZnO]) added and each group was further divided into 3 subgroups (n = 20) for colour, tear strength (TS) and hardness (H) testing. The tests were conducted and data was obtained both before and after outdoor weathering of 6 months.
UNASSIGNED: Minimum colour change after weathering was observed in PTFE group (∆E = 2.23). TiO2 group showed maximum TS (12.01 N/mm) followed by PTFE group (10.85 N/mm) before weathering. After weathering, maximum TS was shown by TiO2 group (12.9 N/mm) and PTFE group (12.54 N/mm). TiO2 group showed maximum hardness (24.15 shore A) before weathering and PTFE group showed maximum hardness (33.43 shore A) after weathering.
UNASSIGNED: Within the limitations of this study, it can be concluded that the addition of polytetrafuoroethylene nanoparticles to the polymer enhances both the optical as well as mechanical properties and can be considered favourable for the extended life of the prosthesis.

The therapeutic potential of tissue engineering in addressing articular cartilage defects has been a focal point of research for numerous years. Despite its promising outlook, a persistent challenge within this domain is the lack of sufficient functional integration between engineered and natural tissues. This study introduces a novel approach that employs a combination of sulforaphane (SFN) nanoemulsion and tannic acid to enhance cartilage tissue engineering and promote tissue integration in a rat knee cartilage defect model. To substantiate our hypothesis, we conducted a series of in vitro and in vivo experiments. The SFN nanoemulsion was characterized using DLS, zeta potential, and TEM analyses. Subsequently, it was incorporated into a ternary polymer hydrogel composed of chitosan, gelatin, and polyethylene glycol. We evaluated the hydrogel with (H-SFN) and without (H) the SFN nanoemulsion through a comprehensive set of physicochemical, mechanical, and biological analyses. For the in vivo study, nine male Wistar rats were divided into three groups: no implant (Ctrl), H, and H-SFN. After inducing a cartilage defect, the affected area was treated with tannic acid and subsequently implanted with the hydrogels. Four weeks post-implantation, the harvested cartilage underwent histological examination employing H&E, safranin O/fast green, alcian blue, and immunohistochemistry staining techniques. Our results revealed that the SFN nanodroplets had an average diameter of 75 nm and a surface charge of -11.58 mV. Moreover, degradation, swelling rates, hydrophilicity, and elasticity features of the hydrogel incorporating SFN were improved. Histopathological analysis indicated a higher production of GAGs and collagen in the H-SFN group. Furthermore, the H-SFN group exhibited superior cartilage regeneration and tissue integration compared to the Ctrl and H groups. In conclusion, the findings of this study suggest the importance of considering cell protective properties in the fabrication of scaffolds for knee cartilage defects, emphasizing the potential significance of the proposed SFN nanoemulsion and tannic acid approach in advancing the field of cartilage tissue engineering.