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Molecules (Basel, Switzerland) Oct 2023Molecularly imprinted polymers (MIPs) have gained significant attention as artificial receptors due to their low cost, mild operating conditions, and excellent... (Review)
Review
Molecularly imprinted polymers (MIPs) have gained significant attention as artificial receptors due to their low cost, mild operating conditions, and excellent selectivity. To optimize the synthesis process and enhance the recognition performance, various support materials for molecular imprinting have been explored as a crucial research direction. Yeast, a biological material, offers advantages such as being green and environmentally friendly, low cost, and easy availability, making it a promising supporting substrate in the molecular imprinting process. We focus on the preparation of different types of MIPs involving yeast and elaborate on the specific roles it plays in each case. Additionally, we discuss the advantages and limitations of yeast in the preparation of MIPs and conclude with the challenges and future development trends of yeast in molecular imprinting research.
Topics: Molecularly Imprinted Polymers; Saccharomyces cerevisiae; Polymers; Polymerization; Molecular Imprinting
PubMed: 37894582
DOI: 10.3390/molecules28207103 -
Nature Communications Nov 2023Cells rapidly respond to replication stress actively slowing fork progression and inducing fork reversal. How replication fork plasticity is achieved in the context of...
Cells rapidly respond to replication stress actively slowing fork progression and inducing fork reversal. How replication fork plasticity is achieved in the context of nuclear organization is currently unknown. Using nuclear actin probes in living and fixed cells, we visualized nuclear actin filaments in unperturbed S phase and observed their rapid extension in number and length upon genotoxic treatments, frequently taking contact with replication factories. Chemically or genetically impairing nuclear actin polymerization shortly before these treatments prevents active fork slowing and abolishes fork reversal. Defective fork remodeling is linked to deregulated chromatin loading of PrimPol, which promotes unrestrained and discontinuous DNA synthesis and limits the recruitment of RAD51 and SMARCAL1 to nascent DNA. Moreover, defective nuclear actin polymerization upon mild replication interference induces chromosomal instability in a PRIMPOL-dependent manner. Hence, by limiting PrimPol activity, nuclear F-actin orchestrates replication fork plasticity and is a key molecular determinant in the rapid cellular response to genotoxic treatments.
Topics: Actins; Polymerization; Cell Line, Tumor; DNA Replication; DNA
PubMed: 38016948
DOI: 10.1038/s41467-023-43183-5 -
International Journal of Molecular... Dec 2023Chitosan is a polymer of natural origins that possesses many favourable properties [...].
Chitosan is a polymer of natural origins that possesses many favourable properties [...].
Topics: Chitosan; Polymers
PubMed: 38203726
DOI: 10.3390/ijms25010554 -
Dental Materials Journal Sep 2023The purpose of the study was the investigation of the polymerization of a preheated composite resin beneath lithium disilicate. First, lithium disilicate discs in two...
The purpose of the study was the investigation of the polymerization of a preheated composite resin beneath lithium disilicate. First, lithium disilicate discs in two shades (HT A2 and HT A4) and three different thicknesses (2, 4, and 6 mm) were bonded on dentine with preheated composite resin that was photo-polymerized for 20 s. The composite resin microhardness, the double bond conversion (DC) and their correlation were estimated. Second, standardized occlusal veneers of two shades and two different thicknesses (4 and 6 mm) were bonded with preheated composite resin and photopolymerized for 60 or 270 s. A microhardness line profiling was performed on the cross-section of each specimen and the correspondence DC was calculated. Shade and thickness of lithium disilicate were found to have a significant impact on micro-hardness and DC of the composite resin. Beneath standardized occlusal veneers DC can reach clinically acceptable level if photopolymerization duration is extended properly.
Topics: Composite Resins; Dental Veneers; Materials Testing; Dental Porcelain; Resin Cements; Ceramics
PubMed: 37661372
DOI: 10.4012/dmj.2023-057 -
European Journal of Paediatric Dentistry Sep 2023The aim of this scoping review is to assess the application of new 3D printed polymeric materials in orthodontics, including polyamide-12 (PA-12) and Shape Memory... (Review)
Review
AIM
The aim of this scoping review is to assess the application of new 3D printed polymeric materials in orthodontics, including polyamide-12 (PA-12) and Shape Memory Polymers (SMPs).
METHODS
A search for articles published until January 2023 was carried out using PubMed, Scopus, Web of Knowledge, Lilacs, Opengrey, Embase and Cochrane Library databases and by applying the search terms (orthodontic* OR paediatric* OR paedodontic*) AND ("3D printed" OR "three-dimensional printed") AND (polymer* OR material* OR resin* OR technopolymer*). Additional records were also screened through hand or electronic search. No restriction in terms of language or publication period was applied.
CONCLUSION
Due to their mechanical, aesthetic and biocompatibility characteristics, PA12 and SMPs can be used in orthodontic practice. However, additional studies should be performed to evaluate the clinical efficiency of these recent materials.
Topics: Humans; Child; Orthodontics; Dental Care; Polymers
PubMed: 37668459
DOI: 10.23804/ejpd.2023.1921 -
Chimia Nov 2023Carbon sequestration to soils counteracts increasing CO2 levels in the atmosphere, and increases soil fertility. Efforts to increase soil carbon storage produced mixed... (Review)
Review
Carbon sequestration to soils counteracts increasing CO2 levels in the atmosphere, and increases soil fertility. Efforts to increase soil carbon storage produced mixed results, due to the multifactorial nature of this process, and the lack of knowledge on molecular details on the interplay of plants, microbes, and soil physiochemical properties. This review outlines the carbon flow from the atmosphere into soils, and factors resulting in elevated or decreased carbon sequestration are outlined. Carbon partitioning within plants defines how much fixed carbon is allocated belowground, and plant and microbial respiration accounts for the significant amount of carbon lost. Carbon enters the soil in form of soluble and polymeric rhizodeposits, and as shoot and root litter. These different forms of carbon are immobilized in soils with varying efficiency as mineral-bound or particulate organic matter. Plant-derived carbon is further turned over by microbes in different soil layers. Microbial activity and substrate use is influenced by the type of carbon produced by plants (molecular weight, chemical class). Further, soil carbon formation is altered by root depth, growth strategy (perennial versus annual), and C/N ratio of rhizodeposits influence soil carbon formation. Current gaps of knowledge and future directions are highlighted.
Topics: Carbon Sequestration; Carbon; Polymers; Soil
PubMed: 38047839
DOI: 10.2533/chimia.2023.726 -
International Journal of Nanomedicine 2024Nanohydrogels (NH) are biodegradable polymers that have been extensively studied and utilized for various biomedical applications. Drugs in a topical medication are... (Review)
Review
Nanohydrogels (NH) are biodegradable polymers that have been extensively studied and utilized for various biomedical applications. Drugs in a topical medication are absorbed via the skin and carried to the intended location, where they are metabolized and eliminated from the body. With a focus on their pertinent contemporary treatments, this review aims to give a complete overview of recent advances in the creation and application of polymer NH in biomedicine. We will explore the key features that have driven advances in nanotechnology and discuss the significance of nanohydrogel-based formulations as vehicles for delivering therapeutic agents topically. The review will also cover the latest findings and references from the literature to support the advancements in nanotechnological technology related to the preparation and application of NH. In addition, we will also discuss the unique properties and potential applications of NH as drug delivery systems (DDS) for skin applications, underscoring their potential for effective topical therapeutic delivery. The challenge lies in efficiently delivering drugs through the skin's barrier to specific areas with high control. Environmentally sensitive systems, like polymer-based NH, show promise in treating dermatological conditions. Polymers are pivotal in developing these drug delivery systems, with NH offering advantages such as versatile drug loading, controlled release, and enhanced skin penetration.
Topics: Drug Delivery Systems; Skin; Polymers; Pharmaceutical Preparations; Nanotechnology
PubMed: 38505165
DOI: 10.2147/IJN.S442123 -
Biological Psychiatry Jan 202415q11.2 deletions and duplications have been linked to autism spectrum disorder, schizophrenia, and intellectual disability. Recent evidence suggests that dysfunctional...
BACKGROUND
15q11.2 deletions and duplications have been linked to autism spectrum disorder, schizophrenia, and intellectual disability. Recent evidence suggests that dysfunctional CYFIP1 (cytoplasmic FMR1 interacting protein 1) contributes to the clinical phenotypes observed in individuals with 15q11.2 deletion/duplication syndrome. CYFIP1 plays crucial roles in neuronal development and brain connectivity, promoting actin polymerization and regulating local protein synthesis. However, information about the impact of single nucleotide variants in CYFIP1 on neurodevelopmental disorders is limited.
METHODS
Here, we report a family with 2 probands exhibiting intellectual disability, autism spectrum disorder, spastic tetraparesis, and brain morphology defects and who carry biallelic missense point mutations in the CYFIP1 gene. We used skin fibroblasts from one of the probands, the parents, and typically developing individuals to investigate the effect of the variants on the functionality of CYFIP1. In addition, we generated Drosophila knockin mutants to address the effect of the variants in vivo and gain insight into the molecular mechanism that underlies the clinical phenotype.
RESULTS
Our study revealed that the 2 missense variants are in protein domains responsible for maintaining the interaction within the wave regulatory complex. Molecular and cellular analyses in skin fibroblasts from one proband showed deficits in actin polymerization. The fly model for these mutations exhibited abnormal brain morphology and F-actin loss and recapitulated the core behavioral symptoms, such as deficits in social interaction and motor coordination.
CONCLUSIONS
Our findings suggest that the 2 CYFIP1 variants contribute to the clinical phenotype in the probands that reflects deficits in actin-mediated brain development processes.
Topics: Humans; Intellectual Disability; Actins; Autism Spectrum Disorder; Polymerization; Adaptor Proteins, Signal Transducing; Fragile X Mental Retardation Protein
PubMed: 37704042
DOI: 10.1016/j.biopsych.2023.08.027 -
Archives of Razi Institute Jun 2023In the transdermal drug delivery system, the drug is administered through the skin and attains a systemic effect. It is a drug administration route that includes drug...
In the transdermal drug delivery system, the drug is administered through the skin and attains a systemic effect. It is a drug administration route that includes drug transport to the epidermis and potentially dermal tissue of the skin for locally therapeutic effect, while an exceptionally significant drug division is transported in systemic blood circulation. This study aimed to formulate rasagiline mesylate (RM) as a transdermal microneedle (MN) delivery. The RM is an antiparkinson drug that can be classified as class III with low permeability and subjected to extensive first-pass metabolism. At first, it was formulated as nanoparticles using the chitosan polymer and ion gelation method. Afterward, the prepared nanoparticles were incorporated into a transdermal MN formulated by a polydimethylsiloxane template. The two-step casting process uses two polymer concentrations of polyvinyl alcohol and mixes them with other polymers in a 3:1 ratio (polyvinylpyrrolidone and chitosan) and glycerin as a plasticizer. The selected MN formula was MN4 with a promising shape, no bubbles, fine and well-formed sharp needles that passed the folding endurance test with 130 folding times before broken, drug content of 97±10.02%, and permeation. The results showed a significant (>0.05) permeability enhancement and increase of flux (160%), compared to the transdermal patch. The RS polymeric nanoparticles were successfully prepared and loaded within dissolving MNs of sufficient mechanical strength to penetrate the stratum corneum and enhance the amount permeated through it to induce the systemic effect transdermally.
Topics: Animals; Chitosan; Administration, Cutaneous; Skin; Nanoparticles
PubMed: 38028835
DOI: 10.22092/ARI.2022.360192.2562 -
ACS Applied Materials & Interfaces Sep 2023Hydrogels are hydrated three-dimensional networks of hydrophilic polymers that are commonly used in the biomedical industry due to their mechanical and structural...
Hydrogels are hydrated three-dimensional networks of hydrophilic polymers that are commonly used in the biomedical industry due to their mechanical and structural tunability, biocompatibility, and similar water content to biological tissues. The surface structure of hydrogels polymerized through free-radical polymerization can be modified by controlling environmental oxygen concentrations, leading to the formation of a polymer concentration gradient. In this work, 17.5 wt % polyacrylamide hydrogels are polymerized in low (0.01 mol % O) and high (20 mol % O) oxygen environments, and their mechanical and tribological properties are characterized through microindentation, nanoindentation, and tribological sliding experiments. Without significantly reducing the elastic modulus of the hydrogel ( ≈ 200 kPa), we demonstrate an order of magnitude reduction in friction coefficient (from μ = 0.021 ± 0.006 to μ = 0.002 ± 0.001) by adjusting polymerization conditions (e.g., oxygen concentration). A quantitative analytical model based on polyacrylamide chemistry and kinetics was developed to estimate the thickness and structure of the monomer conversion gradient, termed the "surface gel layer". We find that polymerizing hydrogels at high oxygen concentrations leads to the formation of a preswollen surface gel layer that is approximately five times thicker ( ≈ 50 μm) and four times less concentrated (≈ 6% monomer conversion) at the surface prior to swelling compared to low oxygen environments ( ≈ 10 μm, ≈ 20% monomer conversion). Our model could be readily modified to predict the preswollen concentration profile of the polyacrylamide gel surface layer for any reaction conditions─monomer and initiator concentration, oxygen concentration, reaction time, and reaction media depth─or used to select conditions that correspond to a certain desired surface gel layer profile.
PubMed: 37650860
DOI: 10.1021/acsami.3c04636