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Abstract Tumor immunotherapy exerts its anti-tumor effects by stimulating and enhancing immune responses of the body. It has become another important modality of anti-tumor therapy with significant clinical efficacy and advantages compared to chemotherapy, radiotherapy and targeted therapy. Although various kinds of tumor immunotherapeutic drugs have emerged, the challenges faced in the delivery of these drugs, such as poor tumor permeability and low tumor cell uptake rate, had prevented their widespread application. Recently, nanomaterials had emerged as a means for treatment of different diseases due to their targeting properties, biocompatibility and functionalities. Moreover, nanomaterials possess various characteristics that overcome the defects of traditional tumor immunotherapy, such as large drug loading capacity, precise tumor targeting and easy modification, thus leading to their wide application in tumor immunotherapy. There are two main classes of novel nanoparticles mentioned in this review: organic (polymeric nanomaterials, liposomes and lipid nanoparticles) and inorganic (non-metallic nanomaterials and metallic nanomaterials). Besides, the fabrication method for nanoparticles, Nanoemulsions, was also introduced. In summary, this review article mainly discussed the research progress of tumor immunotherapy based on nanomaterials in the past few years and offers a theoretical basis for exploring novel tumor immunotherapy strategies in the future.

With the exceptional advantages of safety, greenness, and low cost, photocatalytic H2O2 generation has kindled a wonderful spark, although being severely hampered by the terrible photoinduced exciton recombination, migration, and surface decomposition. Here, employing reflux method, the Cd–Mo–Se quantum dots of varying molar ratios of Cd and Mo were synthesized using thioglycolic acid as the capping ligand to regulate their growth. This type of metal alloying promotes rapid charge migration, improves light harvesting, and reduces the rate of charge recombination. The improved optoelectronic properties and boosted activity of Cd-rich ternary CMSe-1 QDs led to the observed exceptional photocatalytic H2O2 yield of 1403.5 μmol g−1 h−1 (solar to chemical conversion efficiency, 0.27%) under visible light, outperforming the other ternary and Se-based QD photocatalysts. Additionally, CMSe-1 shows 93.6% (2 h) hazardous Cr(VI) photoreduction. The enhanced catalytic performance of CMSe-1 corresponds to effective charge carrier separation and transfer efficiency, well supported by PL, TRPL, and electrochemical measurements. Photocatalytic H2O2 production was also studied under varying experimental conditions and the scavenger test suggests a superoxide radical intermediate 2-step single electron reduction pathway. The catalyst-assisted Cr(VI) reduction is substantiated by the zero-order kinetics as well as the determination of the pHPZC value. The catalyst can be employed for a maximum of four times while retaining its activity, according to the photostability and reusability test outcomes. This research presents interesting approaches for producing ternary QDs and modified systems for efficient photocatalytic H2O2 production and Cr(VI) reduction. [ABSTRACT FROM AUTHOR]

Background: Deferoxamine (DFO) angiogenesis induction potential has been demonstrated in earlier studies, but not in the osteonecrosis of the femoral head (ONFH). In this study, we evaluated the outcome of ONFH treated with combined core decompression and local DFO administration loaded on Polylactic Glycolic Acid (PLGA). Patients and methods: In a pilot experimental study, six patients (10 hips) with early-stage non-traumatic ONFH were treated by core decompression, and concurrent injection of local DFO loaded on PLGA scaffold into the subchondral femoral head. Outcome measures were evaluated before the surgery and 12 and 24 months after the surgery and included visual analog scale (VAS) for pain, modified Merle d'Aubigné-Postel (MAP) score for hip function by MRI, and rate of osteonecrosis assessed by the modified. Results: The mean MPA score was 14.7 ± 1.16 before the surgery and 16.7 ± 1.41 one year after the surgery (P = 0.004). The mean VAS for pain was 4.7 ± 1.25 before the surgery and 1.8 ± 1.03 one year after the surgery (P = 0.005). The mean Kerboul angle was 219 ± 58.64 before the operation and 164.6 ± 41.82 one year after the operation (P < 0.001). Osteonecrosis progression or collapse was not seen in any of the patients at the final follow-up. No postoperative side effect attributed to the DFO was noticed, as well. Conclusion: In short-term follow-up, combined core decompression and local DFO administration not only prevent the progression of ONFH but also reduces the rate of osteonecrosis significantly. However, future controlled studies are required to confirm the present results. Trial registration: IRCT20161121031003N3, 16/04/2019. [ABSTRACT FROM AUTHOR]

The developed bifunctional NNN–Ru complex features a high catalytic efficiency for the selective production of hydrogen and glycolic acid from ethylene glycol under mild reaction conditions, where a TON of 6395 was achieved. Tuning the reaction conditions afforded further dehydrogenation of the organic substrate with higher hydrogen production, and a higher TON of 25 225 was attained. The scale-up reaction yielded 1230 mL of pure hydrogen gas under the optimized reaction conditions. The role of the bifunctional catalyst was studied and mechanistic investigations were performed. [ABSTRACT FROM AUTHOR]

Copyright of Baghdad Science Journal is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study investigated the impact of various enhancers on permeation through the skin and accumulation in the skin from acrylic pressure-sensitive adhesive-based drug-in-adhesives matrix-type transdermal patches. Eleven patches, each containing a 5% enhancer of permeation, encompassing compounds such as salicylic acid, menthol, urea, glycolic acid, allantoin, oleic acid, Tween 80, linolenic acid, camphor, N-dodecylcaprolactam, and glycerin, were developed. Ibuprofen (IBU) was the model active substance, a widely-used non-steroidal anti-inflammatory drug. The results were compared to patches without enhancers and commercial preparations. The study aimed to assess the effect of enhancers on IBU permeability. The adhesive properties of the patches were characterised, and active substance permeability was tested. The findings revealed that patches with 5% allantoin exhibited the highest IBU permeability, approximately 2.8 times greater than patches without enhancers after 24 h. These patches present a potential alternative to commercial preparations, highlighting the significant impact of enhancers on transdermal drug delivery efficiency. [ABSTRACT FROM AUTHOR]

A technique for encapsulating the anti-inflammatory dodecapeptide ingramon into microspheres of a biodegradable copolymer of lactic and glycolic acids (PLGA) to provide prolonged release of the peptide for up to 28 d is presented. The technique makes it possible to achieve >90% encapsulation efficiency and is suitable for producing an injectable suspension that meets the requirements of the State Pharmacopoeia of the Russian Federation. The peptide distribution inside the obtained microspheres and its release kinetics were characterized. A tendency toward suppression of JE/CCL2-dependent monocyte migration was revealed in mice with preliminary (7 d before the experiment) administration of ingramon-depot. [ABSTRACT FROM AUTHOR]

Background: Endoscopic submucosal dissection (ESD) has been the first-line treatment for early-stage esophageal cancer. However, it often causes postoperative stricture in cases requiring wide dissection. Basic fibroblast growth factor (bFGF) reportedly has anti-scarring effects during cutaneous wound healing. We hypothesized that suppressing myofibroblast activation will prevent stricture after esophageal ESD. Methods: We resected a complete porcine esophagus circumference section by ESD. To investigate the preventive effect of bFGF on esophageal stricture formation after ESD, we endoscopically applied bFGF-soaked poly-glycolic acid (PGA) sheets onto the wound bed after ESD and fixed them by spraying fibrin glue (PGA + bFGF group), PGA sheets alone onto the wound bed and fixed them by spraying fibrin glue (PGA group), or nothing (control group). After removing the esophagus on day 22, we evaluated the mucosal constriction rate. Results: Compared with those in the control group, esophageal stricture was significantly reduced in the PGA + bFGF group, and the areas stained with α-SMA and calponin-1 antibodies were significantly inhibited in the PGA + bFGF and PGA groups. The thickness of the fibrous layer in the PGA + bFGF group was uniform compared to that of the other groups. Thus, PGA + bFGF inhibited the development of unregulated fibroblasts in the acute phase, leading to uniform wound healing. Conclusions: Stenosis after esophageal ESD is related to fibrosis in the acute phase. Administration of PGA and bFGF suppresses myofibroblast activation in the acute phase, thereby preventing esophageal constriction in pigs. [ABSTRACT FROM AUTHOR]

Poly(glycolic acid) (PGA) is derived from glycolide obtained by fermenting pineapples or sugarcane, which has excellent gas barrier properties and a small carbon footprint. PGA is a potential substitute for the current aluminum-plastic composite films used in high barrier packaging applications. However, its poor ductility and narrow processing window limit its application in food packaging. Herein, poly(butylene succinate-co-butylene adipate) (PBSA) was used to fabricate PGA/PBSA blend films through an in situ fibrillation technique and blown film extrusion. Under the elongational flow field used during the extrusion process, a unique hierarchical structure based on the PBSA nanofibrils and interfacially oriented PGA crystals was obtained. This structure enhances the strength, ductility and gas barrier properties of the PGA/PBSA blend film. In addition, an epoxy chain extender (ADR4468) was used as a compatibilizer to further enhance the interfacial adhesion between PGA and PBSA. 70PGA/0.7ADR exhibited a very low oxygen permeability (2.34×10−4 Barrer) with significantly high elongating at break (604.4%), tensile strength (47.4 MPa), and transparency, which were superior to those of petroleum-based polymers. Thus, the 70PGA/0.7ADR blown films could satisfy the requirements for most instant foods such as coffee, peanuts, and fresh meat. [ABSTRACT FROM AUTHOR]

For the first time, anisotropic hydrogel material with a highly oriented structure was obtained by the chemical reaction of polymer-analogous transformation of chitosan glycolate—chitosan base using triethanolamine (TEA) as a neutralizing reagent. Tangential bands or concentric rings, depending on the reaction conditions, represent the structural anisotropy of the hydrogel. The formation kinetics and the ratio of the positions of these periodic structures are described by the Liesegang regularities. Detailed information about the bands is given (formation time, coordinate, width, height, and formation rate). The supramolecular ordering anisotropy of the resulting material was evaluated both by the number of Liesegang bands (up to 16) and by the average values of the TEA diffusion coefficient ((15–153) × 10−10 and (4–33) × 10−10 m2/s), corresponding to the initial and final phase of the experiment, respectively. The minimum chitosan concentration required to form a spatial gel network and, accordingly, a layered anisotropic structure was estimated as 1.5 g/dL. Morphological features of the structural anisotropic ordering of chitosan Liesegang structures are visualized by scanning electron microscopy. The hemocompatibility of the material obtained was tested, and its high sorption–desorption properties were evaluated using the example of loading–release of cholecalciferol (loading degree ~35–45%, 100% desorption within 25–28 h), which was observed for a hydrophobic substance inside a chitosan-based material for the first time. [ABSTRACT FROM AUTHOR]

Mesenchymal stem cells (MSCs) have a high tropism for the hypoxic microenvironment of tumors. The combination of nanoparticles in MSCs decreases tumor growth in vitro as well as in rodent models of cancers in vivo. Covalent conjugation of nanoparticles with the surface of MSCs can significantly increase the drug load delivery in tumor sites. Nanoparticle-based anti-angiogenic systems (gold, silica and silicates, diamond, silver, and copper) prevented tumor growth in vitro. For example, glycolic acid polyconjugates enhance nanoparticle drug delivery and have been reported in human MSCs. Labeling with fluorescent particles (coumarin-6 dye) identified tumor cells using fluorescence emission in tissues; the conjugation of different types of nanoparticles in MSCs ensured success and feasibility by tracking the migration and its intratumor detection using non-invasive imaging techniques. However, the biosafety and efficacy; long-term stability of nanoparticles, and the capacity for drug release must be improved for clinical implementation. In fact, MSCs are vehicles for drug delivery with nanoparticles and also show low toxicity but inefficient accumulation in tumor sites by clearance of reticuloendothelial organs. To solve these problems, the internalization or conjugation of drug-loaded nanoparticles should be improved in MSCs. Finally, CXCR4 may prove to be a promising target for immunotherapy and cancer treatment since the delivery of siRNA to knock down this alpha chemokine receptor or CXCR4 antagonism has been shown to disrupt tumor–stromal interactions. [ABSTRACT FROM AUTHOR]

Spot blotch (caused by Bipolaris sorokiniana) is one of the main diseases of barley. In this study we evaluated the effect of silicon (Si) combined with the preventive application of a fungicide on the biochemical defense against spot blotch. For this purpose, we evaluated the activity of antioxidant system enzymes, accumulation of total soluble phenolics (TSPs), the lignin derivatives thioglycolic acid (DLTGA), and their influence in the host membrane damage by determining the electrolyte leakage (EL). Two barley cultivars, AnaG01 and BRS Cauê, both susceptible, were grown in soil not supplied (-Si) or supplied (+ Si) with Si and treated with the fungicide 7 or 15 days before inoculation (dbi). The highest disease severity (up to 29%) was observed for the -Si plants not treated with fungicide. Plants supplied with Si showed lower disease intensity due to an increase in the activity of SOD and reduction in CAT, which may have favored the hydrogen peroxide accumulation as well as increases in the TSP and DLTGA concentrations. The best disease control was achieved by combining Si in the soil and fungicide spray, especially when application occurred at 7 dbi. Furthermore, this combination increased the control at 15 dbi compared to -Si plants, indicating that defense mechanisms enhanced by Si may have favored the fungicidal control at the end of the protective period, reducing the disease intensity. In conclusion, the results of this study showed that Si supply to barley plants promoted the activation of biochemical mechanisms related to the plants' defense, enhancing the control of spot blotch severity by the fungicide. [ABSTRACT FROM AUTHOR]

Pentoxifylline (PTXF) is a vasoactive agent that plays a significant role in the treatment of thin-layer endometrium cases. The PTXF, also identified as oxpentifylline, is a member of xanthine derivatives and a competitive nonselective phosphodiesterase inhibitor leading to the elevation of intracellular cAMP, inhibition of tumor necrosis factor and leukotriene synthesis, activation of protein kinase A, and reduction of inflammation and innate immunity. Moreover, it is used as an agent to relieve muscle pain in people with peripheral artery disease (vascular irregularities). It is also an acceptable choice for the treatment of radiation-induced fibrosis. Therefore, the present study aimed to determine the advantageous impact of PTXF and PTXF-loaded poly lactic-co-glycolic acid (PLGA) on female rats after being exposed to ethanol to create a thin layer of the endometrium. For this purpose, 50 female rats were selected and divided into five groups (G1: negative normal control, G2: positive control, G3: PLGA only, G4: preference PTXF, and G5: PLGA-PTXF groups) for a 20-day treatment period. In this study, the histopathological section revealed a perfect improvement in the tissues of the uterine horn of female rats that induced endometria and were treated with PLGA-PTXF. In this group of rats, clear healing was achieved and there was an increase in the thickness of endometrium and myometrium, compared to the ordinary PTXF-treated group which had the lowest recovery characteristics. However, the positive control group underwent a significant decrease in terms of endometrium and myometrium thickness as well as vascular and glandular density. This study showed that the PTXF-loaded PLGA had the capacity to heal the thin layer of the endometrium by improving the levels of histopathological changes, especially regarding the thickness of the endometrium and myometrium more than the ordinary PTXF. [ABSTRACT FROM AUTHOR]

A convenient and efficient one-pot synthesis method was employed to produce Thioglycolic Acid (TGA) capped Zinc Sulfide (ZnS) Quantum Dots (QDs). Compared to other QDs like CdSe, CdS, CdTe, and ZnSe, confining ZnS QDs was observed to be remarkably sensitive and challenging. Transmission electron microscopy characterization reveals a uniform dispersion of ZnS Quantum Dots (QDs) with an average diameter of 1.2 nm. Complementary calculations using the Bruce equation also estimate a size of 1.5 nm, affirming the consistent size of the QDs. The optical properties analysis indicates an initial optical band gap of 4.01 eV at room temperature. Notably, an intriguing observation is the reduction in band gap as temperature rises. Moreover, the size of the QDs was observed to increase with temperature, while the Urbach energy, revealing of localized states in the bandgap, also exhibited an increase with rising temperature. These temperature-dependent optical properties highlight the tunability of ZnS QDs, which could be advantageous for various applications. The Photo Luminescence (PL) response of the ZnS QDs exhibited a broad blue Photoluminescence band when subjected to a temperature of 90°C. This blue emission is a favourable characteristic for blue light emitters, making ZnS QDs potential candidates for applications in optoelectronic devices and displays. The Fourier-transform Infrared Spectroscopy (FTIR) spectra provided evidence for the successful encapsulation of ZnS QDs with TGA as the capping agent, further supporting the stability and passivation of the QDs' surfaces. [ABSTRACT FROM AUTHOR]

Successfully reconstructing bone and restoring its dynamic function represents a significant challenge for medicine. Critical size defects (CSDs), resulting from trauma, tumor removal, or degenerative conditions, do not naturally heal and often require complex bone grafting. However, these grafts carry risks, such as tissue rejection, infections, and surgical site damage, necessitating the development of alternative treatments. Three-dimensional and four-dimensional printed synthetic biomaterials represent a viable alternative, as they carry low production costs and are highly reproducible. Hyperelastic bone (HB), a biocompatible synthetic polymer consisting of 90% hydroxyapatite and 10% poly(lactic-co-glycolic acid, PLGA), was examined for its potential to support cell adhesion, migration, and proliferation. Specifically, we seeded collagen-coated HB with MG-63 human osteosarcoma cells. Our analysis revealed robust cell adhesion and proliferation over 7 days in vitro, with cells forming uniform monolayers on the external surface of the scaffold. However, no cells were present on the core of the fibers. The cells expressed bone differentiation markers on days 3 and 5. By day 7, the scaffold began to degrade, developing microscopic fissures and fragmentation. In summary, collagen-coated HB scaffolds support cell adhesion and proliferation but exhibit reduced structural support after 7 days in culture. Nevertheless, the intricate 3D architecture holds promise for cellular migration, vascularization, and early osteogenesis. [ABSTRACT FROM AUTHOR]

In this article, we report the synthesis of graphene quantum dots (GQDs) by hydrothermal method and surface modified CdS quantum dots (QDs) via the colloidal method and the fabrication of their dyad. The CdS QDs functionalized by mercaptoacetic acid (MAA) attach to the GQDs via electrostatic interactions. Spectral overlapping between the emission spectrum of GQDs and the absorption spectrum of CdS QDs allows efficient Förster resonance energy transfer (FRET) from GQDs to the CdS QDs in the GQDs-CdS QDs dyads. The magnitude of FRET efficiency (E) and the rate of energy transfer (kE) assessed by the photoluminescence (PL) decay kinetics are ~61.84% and ⁓3.8 × 108 s− 1, respectively. These high values of FRET efficiency and energy transfer rate can be assigned to the existence of strong electrostatic interactions between GQDs and CdS QDs, which arise due to the presence of polar functionalities on the surface of both GQDs and CdS QDs. The understanding of energy transfer in the luminescent donor-acceptor FRET system is of significant importance and the practical implications of such FRET systems could overall improve the efficiency of photovoltaics, sensing, imaging and optoelectronic devices. [ABSTRACT FROM AUTHOR]

The complexation between Al3+ ([Al(H2O)6]3+) and glycolic acid (GA, C2H4O3) which has a carboxyl group and a hydroxyl group in a molecule was investigated under acidic condition using 27Al NMR, 13C NMR and ESI–MS techniques. The five peaks including a peak due to Al3+ were observed in 27Al NMR spectra for the mixed solution of Al3+ and GA, suggesting the existence of at least four Al-GA complexes. The results of NMR and ESI–MS measurements revealed that GA and Al3+ can form one monodentate complex (AlGA2+) and three bidentate complexes (AlGA+, AlGA2−, and AlGA33−) complexes. From the deconvolution of 27Al NMR spectra and pKa value of GA, the conditional formation constants (log10K) of each complex (GA/Al molar ratio of 25 in mixed solution) can be determined to be 0.94 (AlGA2+), − 0.96 (AlGA+), − 0.77 (AlGA2−) and − 2.21 (AlGA33−), respectively. In addition, the overall formation constant of three bidentate complex at pH 3 was also calculated to be − 1.65. [ABSTRACT FROM AUTHOR]

Globally, liver cancer ranks among the most lethal cancers, with chemotherapy being one of its primary treatments. However, poor selectivity, systemic toxicity, a narrow treatment window, low response rate and multidrug resistance limit its clinical application. Liver-targeted nanoparticles (NPs) exhibit excellent targeted delivery ability and promising effectivity in treating liver cancer. The present study aimed to investigate the liver-targeting and anti-liver cancer effect of artesunate (ART)-loaded and glycyrrhetinic acid (GA)-decorated polyethylene glycol (PEG)-poly (lactic-co-glycolic acid) (PLGA) (ART/GA-PEG-PLGA) NPs. GA-coated NPs significantly increased hepatoma-targeted cellular uptake, with micropinocytosis and caveolae-mediated endocytosis as its chief internalization pathways. Moreover, ART/GA-PEG-PLGA NPs exhibited pro-apoptotic effects on HepG2 cells, mainly via the induction of a high level of reactive oxygen species, decline in mitochondrial membrane potential and induction of cell cycle arrest. Additionally, ART/GA-PEG-PLGA NPs induced internal apoptosis pathways by upregulating the activity of cleaved caspase-3/7 and expression of cleaved poly (ADP-Ribose)-polymerase and Phos-p38 mitogen-activated protein kinase in HepG2 cells. Furthermore, ART/GA-PEG-PLGA NPs exhibited higher liver accumulation and longer mean retention time, resulting in increased bioavailability. Finally, ART/GA-PEG-PLGA NPs promoted the liver-targeting distribution of ART, increased the retention time and promoted its antitumour effects in vivo. Therefore, ART/GA-PEG-PLGA NPs afforded excellent hepatoma-targeted delivery and anti-liver cancer efficacy, and thus, they may be a promising strategy for treating liver cancer. [ABSTRACT FROM AUTHOR]

The low melt viscosity and melt strength of polyglycolic acid (PGA) severely limit its application. In this work, high melt viscosity PGA/PLA blends are prepared by reactive extrusion of bifunctional isocyanate (HDI) and multifunctional epoxy oligomer (ADR) as chain extenders. The use of hybrid chain extender (hCE) containing 2 wt% HDI and 1 wt% ADR results in a long chain branched/cross‐linked structure, thus increasing melt viscosity more effectively than HDI or ADR alone. The complex viscosity, storage modulus and loss modulus of the PGA/PLA/hCE blends are significantly higher than those of the PGA/hCE. The 60PGA/40PLA/hCE has the highest complex viscosity of 72,115 Pa s, which is 69 times of that of PGA/hCE. The modification of hCE significantly improved the mechanical performance of PGA/PLA blend, with the 60PGA/40PLA/hCE having the highest tensile strength and flexural strength. The crystallization temperature and crystallinity of the PGA component in the PGA/PLA/hCE blend are significantly reduced in comparison to that of the PGA/hCE. The PGA/PLA/hCE has the best thermal stability, with the T−5% of 355.3°C, almost 45°C higher than pure PGA. The SEM results show that the adding of hCE decreased the domain size of the PLA dispersed phase in PGA/PLA blend, due to the in situ compatibilization. [ABSTRACT FROM AUTHOR]

Acne vulgaris stands out as the most prevalent skin disorder among teenagers and young adults, causing physical discomfort and considerable economic and psychological burdens on individuals and society. A wide range of topical and systemic therapies are available in acne treatment. Chemical peeling is a skin resurfacing technique designed to rebuild healthy skin using exfoliating substances, a simple and affordable process with various dermatological uses. Chemical peels, classified as superficial, medium, and deep, have been utilized for acne vulgaris and multiple other skin issues. In these chemical peels, a diverse range of chemical substances is employed, each with its unique mode of action. Among these, α-hydroxy and β-hydroxy acids have gathered attention for their efficacy in reducing acne lesions and enhancing overall skin appearance. Acids, such as salicylic acid, glycolic acid, or lactic acid, are commonly used in chemical peels due to their exfoliating and sebum-regulating properties. Despite the widespread use of these acids, there exists a lack of consensus regarding the most effective acid type and concentration for treating acne-prone skin. This review aims to bridge this knowledge gap by evaluating the effectiveness and safety of various organic acids used in chemical peels specifically for acne-prone skin. The findings of this comprehensive bibliographic review indicate that organic acid-based chemical peels represent effective and safe treatment options for individuals with acne-prone skin. Their adaptability sets these treatments apart; the choice of organic acid can be tailored to meet individual patient needs and tolerability levels. This personalized approach ensures that patients receive optimal care while minimizing the risks associated with the treatment. As research in this field progresses, it is anticipated that a more nuanced understanding of the ideal acid type and concentration will emerge, further enhancing the efficacy and safety of chemical peels for acne-prone skin. [ABSTRACT FROM AUTHOR]

Copyright of Plastics Science & Technology / Suliao Ke-Ji is the property of Plastics Science & Technology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Thiazolidinediones (TZDs) are the vital component of a number of pharmaceuticals and biologically active compounds. Owing to the diversified pharmaceutical applications of TZD derivatives, we conceived a new synthetic approach for the preparation of a series of spiro-thiazolidinediones by the reaction of synthesized TZDs with thioglycolic acid. Melting point and thin-layer chromatography ascertained the purity of the synthesized compounds. Elemental analysis, FTIR, 1H and 13C NMR spectral studies have been used for the characterization of the synthesized compounds. The synthesized chalcones, thiazine, TZDs, and spiro-thiazolidinediones are in accordance with the standard values of different spectral techniques. The appearance of a sharp singlet of two protons of CH2 at 2.5 – 3.0 ppm in 1H NMR of spiro-thiazolidinediones, which was absent in TZDs, suggests the formation of a spiro ring. All the novel compounds were screened for their antimicrobial activity on Gram-negative (P. aeruginosa, E. coli) and Gram-positive (B. subtilis, S. aureus) bacteria. The final synthesized compounds exhibited excellent to good responses against the tested microbes. The change of the substituent and its position plays a significant role in the activity of the synthesized spiro-thiazolidinediones. [ABSTRACT FROM AUTHOR]

Cryopreservation in liquid nitrogen (LN, −196 °C) is a unique option for the long-term conservation of threatened plant species with non-orthodox or limitedly available seeds. In previous studies, a systematic approach was used to develop a droplet-vitrification (DV) cryopreservation protocol for Postemon yatabeanus shoot tips that includes preculture with 10% sucrose, osmoprotection with C4-35%, cryoprotection with A3-80% vitrification solution, and a three-step regrowth starting with the ammonium-free medium. The tricarboxylic acid (TCA) cycle is a crucial component of plant cell metabolism as it is involved in redox state regulation and energy provision. We hypothesized that organic acids (OAs) associated with the TCA and its side reactions indirectly indicate metabolism intensity and oxidative stress development in shoot tips under the cryopreservation procedure. In this study, the contents of 14 OAs were analyzed using gas chromatography–tandem mass spectrometry (GC-MS/MS) in P. yatabeanus shoot tips in a series of treatments including individual steps of the DV procedure, additional stress imposed by non-optimum protocol conditions (no preculture, no osmoprotection, various vitrification solution composition, using vials instead of aluminum foils, etc.) and regrowth on different media with or without ammonium or growth regulators. The possible relation of OA content with the total cryoprotectant (CPA) concentration and shoot tips regeneration percentage was also explored. Regeneration of cryopreserved shoot tips reduced in descending order as follows: standard protocol condition (91%) > non-optimum vitrification solution (ca. 68%) > non-optimum preculture (60–62%) > regrowth medium (40–64%) > no osmoprotection, cryopreservation in vials (28–30%). Five OAs (glycolic, malic, citric, malonic, and lactic) were the most abundant in the fresh (control) shoot tips. The dynamic pattern of OAs during the DV procedure highly correlated (r = 0.951) with the total CPA concentration employed: it gradually increased through the preculture, osmoprotection, and cryoprotection, peaked at cooling/rewarming (6.38-fold above control level), and returned to the fresh control level after 5 days of regrowth (0.89-fold). The contents of four OAs (2-hydroxybutyric, 3-hydroxypropionic, lactic, and glycolic) showed the most significant (10-209-fold) increase at the cooling/rewarming step. Lactic and glycolic acids were the major OAs at cooling/rewarming, accounting for 81% of the total OAs content. The OAs were categorized into three groups based on their dynamics during the cryopreservation protocol, and these groups were differently affected by protocol step modifications. However, there was no straightforward relationship between the dynamics of OAs and shoot tip regeneration. The results suggest that active modulation of OAs metabolism may help shoot tips to cope with osmotic stress and the chemical cytotoxicity\ of CPAs. Further intensive studies are needed to investigate the effect of cryopreservation on cell primarily metabolism and identify oxidative stress-related biomarkers in plant materials. [ABSTRACT FROM AUTHOR]

Methyl glycolate was synthesized as a precursor to ethylene glycol from the acid-catalyzed carbonylation of formaldehyde, followed by esterification with methanol. Homogeneous acids and different solid acids (e.g., resins and zeolites) were used as catalysts, and the effect of the solvent was examined. Afterward, a carboxylic acid protection strategy was proposed. With sulfolane and acetic acid as the mixed solvent, the solubility of CO increases, and the reaction rate can be accelerated. The rapid reaction between acetic acid and glycolic acid inhibits glycolic acid polymerization and pulls the reaction balance to promote the carbonylation reaction rate. Under the optimal solvent system (a molar ratio of acetic acid to sulfolane of 1:5) and the appropriate reaction conditions, the selectivity of the target product is higher than 85%. Solid acid catalysts with a −SO3H or −CF2SO3H functional group are supposed to be efficient in the carbonylation of formaldehyde, based on which a supported Nafion catalyst with a high surface area and total acid content was designed and synthesized. The novel supported Nafion catalyst presents a high total acid content and high Brönsted–Lewis acid ratio due to the characteristics of modified zeolite and, thus, leads to the high reactivity and very low selectivity of the by-product. A possible reaction mechanism is proposed to explain the product's distribution by ascribing the formation of different products to different types of acid sites. [ABSTRACT FROM AUTHOR]

In this paper, we discuss general trends in the IR luminescence of colloidal PbS quantum dots 3 nm in average size, capped with thioglycolic acid molecules (PbS/TGA QDs). Treatment of the PbS/TGA QDs with a KI solution has been shown to cause a shift of a composite luminescence band peaking at 1120 nm to shorter wavelengths, to 1060 nm; an increase in the quantum yield of its shorter wavelength component, related to excitonic emission, from 1 to 10%; and quenching of its longer wavelength component, due to radiative recombination at defect levels. In this process, the cubic structure of PbS undergoes no changes. The average size of the PbS/TGA QDs has been shown to decrease slightly, by 0.2–0.3 nm. The conclusion has been drawn that the increase in the quantum yield of excitonic emission from the PbS/TGA QDs as a result of KI treatment is due to the more efficient passivation of interfacial defects, which act as both recombination luminescence and nonradiative carrier recombination channels. Using thermoluminescence in the temperature range from 80 to 350 K, we have demonstrated the presence of two types of shallow localized states, at 0.17- and 0.25-eV depths, whose density is only slightly sensitive to treatment of the PbS/TGA QDs with a KI solution. We assume that some of the traps identified are due to native defects in the nanocrystals—interstitial lead and sulfur ions—rather than to dangling bonds of surface lead and sulfur atoms. [ABSTRACT FROM AUTHOR]

In situ forming implants (ISFI) based on poly(lactic-co-glycolic acid) (PLGA) are promising long-acting injectable depots for the treatment of human immunodeficiency virus-1 infection. One of the key parameters of depot formulations is the drug release rate which is critical for the development of optimal dosing regimens. The goal of this research is to investigate the most significant factors affecting the rilpivirine release rate from PLGA-based ISFI, including the influence of the polymer content and structure (i.e. molecular weights, lactide/glycolide ratios, and chemistry of the terminal group). Thus, the use of a low molecular weight PLGA reduces the burst-effect from 17.5 to 4.7% of the drug content and enables continuous release of rilpivirine over the period of 42 days. At the same time, a more hydrophobic PLGA with a lactide/glycolide ratio of 75/25 and a terminal ester group affects to a greater extent the rilpivirine release rate in the third phase of the release process, when destruction of the polymer matrix starts. The rilpivirine release profile from the implant, formed by using a 30% (w/w) solution of PLGA with a higher content of lactic acid (75:25) and a terminal ester group, is similar to the dissolution profile of rilpivirine nanocrystals (Rekambis®). [ABSTRACT FROM AUTHOR]

The utilization of topical formulations containing alpha hydroxy acids (AHAs) has garnered considerable attention. This review summarizes the effectiveness of the most common topical AHA formulations, including mechanisms of action and future research directions. AHAs have a dramatic impact on diverse skin conditions, enhancing texture and stimulating collagen synthesis. Uncertainties persist regarding optimal concentration, pH, and vehicle for maximum efficacy. Advancements in formulation technologies offer opportunities for AHA penetration and stability. Understanding mechanisms is vital for skincare optimization. The review covers AHAs, their concentrations, formulation considerations, safety measures, and future directions. [ABSTRACT FROM AUTHOR]

Metallic materials for long‐term load‐bearing implants still do not provide high antimicrobial activity while maintaining strong compatibility with bone cells. This study aimed to modify the surface of Ti13Nb13Zr alloy by electrophoretic deposition of a chitosan coating with a covalently attached Arg‐Gly‐Asp (RGD) peptide. The suspensions for coating deposition were prepared in two different ways either using hydroxyacetic acid or a carbon dioxide saturation process. The coatings were deposited using a voltage of 10 V for 1 min. The prepared coatings were examined using SEM, EDS, FTIR, and XPS techniques. In addition, the wettability of these surfaces, corrosion resistance, adhesion of the coatings to the metallic substrate, and their antimicrobial activity (E. coli, S. aureus) and cytocompatibility properties using the MTT and LDH assays were studied. The coatings produced tightly covered the metallic substrate. Spectroscopic studies confirmed that the peptide did not detach from the chitosan chain during electrophoretic deposition. All tested samples showed high corrosion resistance (corrosion current density measured in nA/cm2). The deposited coatings contributed to a significant increase in the antimicrobial activity of the samples against Gram‐positive and Gram‐negative bacteria (reduction in bacterial counts from 99% to, for CS‐RGD‐Acid and the S. aureus strain, total killing capacity). MTT and LDH results showed high compatibility with bone cells of the modified surfaces compared to the bare substrate (survival rates above 75% under indirect contact conditions and above 100% under direct contact conditions). However, the adhesion of the coatings was considered weak. [ABSTRACT FROM AUTHOR]

Over three major convenient steps, a series of some novel Bis-Schiff bases, and Bis 1,3-thiazolidin-4-one derivatives have been synthesized: Firstly, the etherification process through the reaction of the 4-hydroxybenzaldehyde substrate with o-, m-, and p-chlorobenzylchlorides under mild circumstances. Secondly, the condensation reaction between 4-((chlorobenzyl)oxy)benzaldehyde compounds with a number of aromatic diamines in an acidic environment produces the required Bis-schiff intermediates. Finally, the practical cyclization step was finished by synthesizing the required Bis 1,3-thiazolidin-4-one products with 79-97% yields through refluxing reaction in benzene with thioglycolic acid. [ABSTRACT FROM AUTHOR]

The effect of Au nanoparticles (AuNPs) on the photoluminescence (PL) of AgInS2/ZnS quantum dots (QDs) in buffer solutions was investigated. The QDs stabilized with mercaptoacetic acid and glutathione were modified by 19-bases thiolated oligonucleotides, and the AuNPs grown in citrate solution and stabilized with lipoic acid and mercaptohexanol were modified by 26-bases thiolated oligonucleotide. These oligonucleotides are not complementary to each other. The nanoobjects were placed in buffer solutions of SSC with different dilutions (0.1 × , 0.25 × , 0.5 × SSC). The PL and optical absorption (OA) spectra of prepared solutions were studied. In the buffer solutions of different dilutions, the formation of aggregates of AuNPs depends on QDs' stabilizing ligands and presence/absence of oligonucleotides on AuNPs' surface, which was detected by specific changes in the OA spectra. The degree of PL quenching also was different in solution with modified and unmodified nanoobjects. The solutions were additionally incubated at room temperature for 24 h to see the dynamic of changing in the interaction between AuNPs and QDs, one of the manifestations of this interaction was an electrolytic aggregation. It is proposed that the observed decrease of PL intensity (PLI) in solutions with unmodified nanoobjects is due to the partial absorption of excitation light by AuNPs, and the interaction between QDs and AuNPs is caused by the presence of noncomplementary oligonucleotides on their surface. [ABSTRACT FROM AUTHOR]

Copyright of Chemistry & Industry of Forest Products is the property of Chemistry & Industry of Forest Products Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Electrospun fibrous scaffolds made from polymers such as polycaprolactone (PCL) have been used in drug delivery and tissue engineering for their viscoelasticity, biocompatibility, biodegradability, and tunability. Hydrophobicity and the prolonged degradation of PCL causes inhibition of the natural tissue-remodeling processes. Poliglecaprone (PGC), which consists of PCL and Poly (glycolic acid) (PGA), has better mechanical properties and a shorter degradation time compared to PCL. A blend between PCL and PGC called PPG can give enhanced shared properties for biomedical applications. In this study, we fabricated a blend of PCL and PGC nanofibrous scaffold (PPG) at different ratios of PGC utilizing electrospinning. We studied the physicochemical and biological properties, such as morphology, crystallinity, surface wettability, degradation, surface functionalization, and cellular compatibility. All PPG scaffolds exhibited good uniformity in fiber morphology and improved mechanical properties. The surface wettability and degradation studies confirmed that increasing PGC in the PPG composites increased hydrophilicity and scaffold degradation respectively. Cell viability and cytotoxicity results showed that the scaffold with PGC was more viable and less toxic than the PCL-only scaffolds. PPG fibers were successfully coated with polydopamine (PDA) and collagen to improve degradation, biocompatibility, and bioactivity. The nanofibrous scaffolds synthesized in this study can be utilized for tissue engineering applications such as for regeneration of human articular cartilage regeneration and soft bones. [ABSTRACT FROM AUTHOR]

Poly(lactic acid) is one of the most commonly used bioplastics thanks to its mechanical performance and low environmental impact. Strategies to overcome excessive rigidity of PLA are constantly investigated. Poor viscoelastic behavior and brittleness of PLA seriously limit its potential application as a common film material. Herein highly amorphous Poly(3-hydroxybutyrate-4-hydroxybutyrate) (P(3HB)(4HB)) was introduced to improve toughness and reduce brittleness of PLA. Anti-blocking (silica) and anti-slipping agent (Ethylene bis-stearamide (EBS)) were added to improve the processability of the blends, specifically to solve winding issues of the blown film and unfolding of the layflat. In this study three formulations containing PLA and different ratios of P(3HB)(4HB), specifically 10-20-30% were extruded. The mechanical, thermal and surface characterization of the films was performed. The tensile and the tear strength test results show that P(3HB)(4HB) increased the ductility of PLA based films. Increasing amounts of P(3HB)(4HB) provide a toughening effect on PLA/P(3HB)(4HB) blown films without altering transparency of PLA. Moreover, the processing additives proved to be efficient in improving film blowing stability and avoiding tackiness during the winding phase of the film. [ABSTRACT FROM AUTHOR]

Copyright of Iraqi Journal of Science is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The choice of capping agents used during the synthesis process of quantum dots (QDs) can significantly influence their fate and fundamental properties. Hence, choosing an appropriate capping agent is a critical step in both synthesis and biomedical application of QDs. In this research, ZnS QDs were synthesized via chemical precipitation process and three commonly employed capping agents, namely mercaptoethanol (ME), mercaptoacetic acid (MAA), and cysteamine (CA), were used to stabilize the QDs. This study was aimed to examine how these capping agents impact the physicochemical and optical characteristics of ZnS QDs, as well as their interactions with biological systems. The findings revealed that the capping agents had considerable effects on the behavior and properties of ZnS QDs. MAA‐QD exhibited superior crystal lattice, smaller size, and significant quantum yield (QY). In contrast, CA‐QDs demonstrated the lowest QY and the highest tendency for aggregation. ME‐QDs exhibited intermediate characteristics, along with an acceptable level of cytotoxicity, rapid uptake by cells, and efficient escape from lysosomes. Consequently, it is advisable to select capping agents in accordance with the specific objectives of the research. [ABSTRACT FROM AUTHOR]

Background: Plastics are an indispensable part of our daily life. However, mismanagement at their end-of-life results in severe environmental consequences. The microbial conversion of these polymers into new value-added products offers a promising alternative. In this study, we engineered the soil-bacterium Comamonas testosteroni KF-1, a natural degrader of terephthalic acid, for the conversion of the latter to the high-value product 2-pyrone-4,6-dicarboxylic acid. Results: In order to convert terephthalic acid to 2-pyrone-4,6-dicarboxylic acid, we deleted the native PDC hydrolase and observed only a limited amount of product formation. To test whether this was the result of an inhibition of terephthalic acid uptake by the carbon source for growth (i.e. glycolic acid), the consumption of both carbon sources was monitored in the wild-type strain. Both carbon sources were consumed at the same time, indicating that catabolite repression was not the case. Next, we investigated if the activity of pathway enzymes remained the same in the wild-type and mutant strain. Here again, no statistical differences could be observed. Finally, we hypothesized that the presence of a pmdK variant in the degradation operon could be responsible for the observed phenotype and created a double deletion mutant strain. This newly created strain accumulated PDC to a larger extent and again consumed both carbon sources. The double deletion strain was then used in a bioreactor experiment, leading to the accumulation of 6.5 g/L of product in 24 h with an overall productivity of 0.27 g/L/h. Conclusions: This study shows the production of the chemical building block 2-pyrone-4,6-dicarboxylic acid from terephthalic acid through an engineered C. testosteroni KF-1 strain. It was observed that both a deletion of the native PDC hydrolase as well as a pmdK variant is needed to achieve high conversion yields. A product titer of 6.5 g/L in 24 h with an overall productivity of 0.27 g/L/h was achieved. [ABSTRACT FROM AUTHOR]

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this research, first, nanoporous zeolite‐NaY was functionalized with 3‐chloropropyltriethoxysilane (organic linker) and then N‐methylimidazole group. Then magnetic nanoparticles (Fe3O4) under ultrasonic energy conditions on the surface and internal pores of zeolite‐Y (1‐MeIm IL@ZY‐Fe3O4) were formed. The identification, confirmation of the structure and morphology of the prepared magnetic nanohybrid was done by using FTIR, FESEM, TEM, EDX, TGA, XRD, VSM and BET instrumental techniques. Next, its catalytic performance in the synthesis of a number of 3‐benzimidazolyl (or benzothiazolyl)‐1,3‐thiazolidin‐4‐one derivatives was investigated through the three‐component condensation reaction of various aromatic aldehydes, 2‐aminobenzimidazole or 2‐aminobenzothiazole, and thioglycolic acid in EtOH at room temperature. The results of the experiments show that the presence of magnetic nanoparticles (Fe3O4) inside the pores of zeolite functionalized with ionic liquid not only causes easy and quick separation of the nanocatalyst by an external magnetic field but also can be effective in catalyzing the reaction as a Lewis acid. [ABSTRACT FROM AUTHOR]

Modern research has evolved several approaches toward skin regeneration and one of the novel concerns is the use of polymer-based systems due to their excellent beneficial properties to the skin. Several polymers, such as cellulose, hyaluronan, alginate, chitosan, collagen, fibrin and fibroin, have been tested and have proven the benefits for skin regeneration, and most of them are derived from either polysaccharide- or protein-based materials. In order to understand the mode of action, several researchers investigated the cell–matrix interaction and possible signaling mechanism in skin regeneration. Not only the signaling mechanism but also the mode of cell communication determines the application of polysaccharide- and protein-based polymers in practice. Based on the above significance, this review disclosed the recent findings to compile a possible method of communication between cells and polymers derived from polysaccharide-based (such as cellulose, hyaluronan, chitosan, alginate, agar, and xanthan gum) and protein-based (such as collagen, gelatin, fibrin, and silk fibroin) materials along with other polymers, such as poly(vinyl alcohol), polyglycolide or poly(glycolic acid), or poly(lactic acid) in skin regeneration. Accordingly, this review addresses the fundamental concept of cell–matrix communication, which helps us to understand the basis of the polymer's functions in the biomedical field. [ABSTRACT FROM AUTHOR]

Various hydroxyapatite-filled and unfilled microspheres based on lactide and glycolide copolymers were prepared. The synthesized poly(lactic-co-glycolic acid) (PLGA) samples were characterized by GPC and 1H NMR spectroscopy, the morphology was characterized by SEM. It was shown that under the tin (II) 2-ethylhexanoate catalysis the glycolide is highly active in copolymerization as compared with lactide. According to the data on weight loss and the weight average molecular weight shift of PLGA over time (pH = 6.5; t = 25 °C), an increase in the rate of microsphere destruction was noted when macromolecules were enriched with glycolic acid residues, as well as when filled with hydroxyapatite. It was shown that the rate of PLGA degradation was determined by the water-accessible surface of a sample. The rate increase in PLGA hydrolytic degradation both with an increase in glycolic acid residues mole fraction in the chain and upon filling with hydroxyapatite was the result of the microspheres' surface hydrophilization, an increase in capillary pressure upon filling of the pores as well as of the defects with water, and an increase in the number of structural defects. Approaches to the creation of composite microspheres based on PLGA degrading at a controlled rate were proposed. [ABSTRACT FROM AUTHOR]

Poly(glycerol) (PG) functionalization is versatile to make various nanoparticles dispersible in aqueous media. In addition, the abundant hydroxy groups in PG give scaffolds for further modification to introduce suitable functional groups. For example, carboxylic group (−COOH) has been introduced through the reaction of hydroxy (−OH) group in PG with succinic anhydride. However, ester linkage in the succinate moiety in the PG layer is subjected to hydrolysis. In this work, we develop an alternative way for a novel −COOH containing PG functionalized detonation nanodiamonds (DND‐PG‐COOH) via oxidation of primary −OH group of PG chain by nitroxyl radical catalysts well‐known as TEMPO or its analogues. The content of −COOH is found to be precisely controlled by the amount of oxidant. [ABSTRACT FROM AUTHOR]

Herein, three different water‐soluble functional groups capped vanadium disulfide quantum dots (VS2QDs), namely, L‐cysteine capped VS2QDs (L‐cys‐VS2QDs), thioglycolic acid capped VS2QDs (TGA‐VS2QDs), and 3‐mercaptopropionic acid capped VS2QDs (MPA‐VS2QDs) are synthesized via hydrothermal method. The comparison of the biocompatibility (MTT assay) of three differently capped VS2QDs is performed in RAW cell 264.7 cells with different concentrations (500, 250, 125, 62.5, 15.625, 7.812, and 3.906 μg mL−1). It is found that L‐cys‐VS2QDs show more biocompatibility than the TGA‐VS2QDs and MPA‐VS2QDs. However, at low concentrations, TGA‐VS2QDs also show better biocompatibility, whereas MPA‐VS2QDs show the least biocompatibility. Biocompatibility of L‐cys‐VS2QDs is also almost consistent with entire range of QDs concentrations may be due to L‐cys cellular inflammation and maintaining pH buffer. [ABSTRACT FROM AUTHOR]

The development of biopolymer scaffolds for intestine regeneration is one of the most actively developing areas in tissue engineering. However, intestinal regenerative processes after scaffold implantation depend on the activity of the intestinal microbial community that is in close symbiosis with intestinal epithelial cells. In this work, we study the impact of different scaffolds based on biocompatible poly(3-hydroxybutyrate) (PHB) and alginate (ALG) as well as PHB/ALG scaffolds seeded with probiotic bacteria on the composition of gut microbiota of Wistar rats. Implantation of PHB/ALG scaffolds on the large-intestine wall to close its injury showed that alpha diversity of the gut microbiota was not reduced in rats implanted with different PHB/ALG scaffolds except for the PHB/ALG scaffolds with the inclusion of Lactobacillus spheres (PHB/ALG-L). The composition of the gut microbiota of rats implanted with PHB/ALG scaffolds with probiotic bacteria or in simultaneous use of an antimicrobial agent (PHB/ALG-AB) differed significantly from other experimental groups. All rats with implanted scaffolds demonstrated shifts in the composition of the gut microbiota by individual operational taxonomic units. The PHB/ALG-AB construct led to increased abundance of butyrate-producing bacteria: Ileibacterium sp. dominated in rats with implanted PHB/ALG-L and Lactobacillus sp. and Bifidobacterium sp. dominated in the control group. In addition, the PHB/ALG scaffolds had a favourable effect on the growth of commensal bacteria. Thus, the effect of implantation of the PHB/ALG scaffold compared to other scaffolds on the composition of the gut microbiota was closest to the control variant, which may demonstrate the biocompatibility of this device with the microbiota. [ABSTRACT FROM AUTHOR]

The rise in the resistance to antibiotics is due to their inappropriate use and the use of a broad spectrum of antibiotics. This has also contributed to the development of multidrug-resistant microorganisms, and due to the unavailability of suitable new drugs for treatments, it is difficult to control. Hence, there is a need for the development of new novel, target-specific antimicrobials. Nanotechnology, involving the synthesis of nanoparticles, may be one of the best options, as it can be manipulated by using physicochemical properties to develop intelligent NPs with desired properties. NPs, because of their unique properties, can deliver drugs to specific targets and release them in a sustained fashion. The chance of developing resistance is very low. Polymeric nanoparticles are solid colloids synthesized using either natural or synthetic polymers. These polymers are used as carriers of drugs to deliver them to the targets. NPs, synthesized using poly-lactic acid (PLA) or the copolymer of lactic and glycolic acid (PLGA), are used in the delivery of controlled drug release, as they are biodegradable, biocompatible and have been approved by the USFDA. In this article, we will be reviewing the synthesis of PLGA-based nanoparticles encapsulated or loaded with antibiotics, natural products, or metal ions and their antibacterial potential in various medical applications. [ABSTRACT FROM AUTHOR]

The delivery of drugs through the skin barrier at a predetermined rate is the aim of transdermal drug delivery systems (TDDSs). However, so far, TDDS has not fully attained its potential as an alternative to hypodermic injections and oral delivery. In this study, we presented a proof of concept of a dual drug-loaded patch made of nanoparticles (NPs) and ultrafine fibers fabricated by using one equipment, i.e., the electrospinning apparatus. Such NP/fiber systems can be useful to release drugs locally through the skin and the tympanic membrane. Briefly, dexamethasone (DEX)-loaded poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBHV) fiber meshes were decorated with rhodamine (RHO)-loaded poly(lactic-co-glycolic acid) (PLGA) NPs, with RHO representing as a second drug model. By properly tuning the working parameters of electrospinning, DEX-loaded PHBHV fibers (i.e., by electrospinning mode) and RHO-loaded PLGA NPs (i.e., by electrospray mode) were successfully prepared and straightforwardly assembled to form a TDDS patch, which was characterized via Fourier transform infrared spectroscopy and dynamometry. The patch was then tested in vitro using human dermal fibroblasts (HDFs). The incorporation of DEX significantly reduced the fiber mesh stiffness. In vitro tests showed that HDFs were viable for 8 days in contact with drug-loaded samples, and significant signs of cytotoxicity were not highlighted. Finally, thanks to a beaded structure of the fibers, a controlled release of DEX from the electrospun patch was obtained over 4 weeks, which may accomplish the therapeutic objective of a local, sustained and prolonged anti-inflammatory action of a TDDS, as is requested in chronic inflammatory conditions, and other pathological conditions, such as in sudden sensorineural hearing loss treatment. [ABSTRACT FROM AUTHOR]

In this study, a promising modified composite scaffold (hydroxyapatite/hyperbranched polyitaconic acid/chitosan) was synthesized for bone tissue engineering. Novel hyperbranched polyitaconic acid was prepared through the polymerization of itaconic acid using reversible addition fragmentation chain transfer using a macro‐RAFT agent. The chemical structure of the prepared hyperbranched polyitaconic acid was characterized by FTIR and 1HNMR and was subsequently embedded into hydroxyapatite/chitosan composite. The obtained modified composite scaffold was evaluated by characterizing its porosity, mechanical properties, bioactivity and cytotoxicity. The results showed that the modified composite scaffold had higher mechanical strength (i.e., 0.56 ± 0.03 MPa) in comparison to chitosan/hydroxyapatite scaffold only (i.e., 0.31 ± 0.01 MPa) and also showed higher bioactivity. In addition, the modified composite scaffold (HAP/HBP‐RAFT‐PI/CS) showed anticancer properties and enhanced human skin fibroblasts proliferation. [ABSTRACT FROM AUTHOR]