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Organic & Biomolecular Chemistry Jan 2022Amphiphilic polymers can self-assemble to form nanoparticles with different structures under suitable conditions. Polymer nanoparticles functionalized with aromatic azo... (Review)
Review
Amphiphilic polymers can self-assemble to form nanoparticles with different structures under suitable conditions. Polymer nanoparticles functionalized with aromatic azo groups are endowed with photo-responsive properties. In recent years, a variety of photoresponsive polymers and nanoparticles have been developed based on azobenzene, using different molecular design strategies and synthetic routes. This article reviews the progress of this rapidly developing research field, focusing on the structure, synthesis, assembly and response of photo-responsive polymer assemblies. According to the molecular structure, photo-responsive polymers can be divided into linear polymers containing azobenzene in a side chain, linear polymers containing azobenzene in the main chain, linear polymers containing azobenzene in an end group, branched polymers containing azobenzene and supramolecular polymers containing azobenzene. These systems have broad biomedical application prospects in the field of drug delivery and imaging applications.
Topics: Azo Compounds; Drug Delivery Systems; Nanostructures; Optical Imaging; Polymers
PubMed: 34908082
DOI: 10.1039/d1ob01823j -
Nanomedicine (London, England) Feb 2024Stimuli-responsive polymersomes are promising tools for protein-based therapies, but require deeper understanding and optimization of their pathology-responsive...
Stimuli-responsive polymersomes are promising tools for protein-based therapies, but require deeper understanding and optimization of their pathology-responsive behavior. Hyaluronic acid (HA)-poly(b-lactic acid) (PLA) polymersomes self-assembled from block copolymers of varying molecular weights of HA were compared for their physical properties, degradation and intracellular behavior. Major results showed increasing enzyme-responsivity associated with decreasing molecular weight. The major formulation differences were as follows: the HA(5 kDa)-PLA formulation exhibited the most pronounced release of encapsulated proteins, while the HA(7 kDa)-PLA formulation showed the most different release behavior from neutral. We have discovered design rules for HA-PLA polymersomes for protein delivery, with lower molecular weight leading to higher encapsulation efficiency, greater release and greater intracellular uptake.
Topics: Polyethylene Glycols; Polymers; Hyaluronic Acid; Polyesters; Drug Carriers
PubMed: 38271081
DOI: 10.2217/nnm-2023-0300 -
Journal of Molecular Modeling Nov 2022In order to reduce the vulnerability, the responses to shock waves for booster explosives JO9C, JH14, JH6, and insensitive RDX were evaluated using shock wave partition...
In order to reduce the vulnerability, the responses to shock waves for booster explosives JO9C, JH14, JH6, and insensitive RDX were evaluated using shock wave partition loading test. To explain the experimental results, molecular dynamics simulation, intermolecular interaction and bond dissociation energy (BDE), and shock initiation pressures were evaluated using the B3LYP, MP2 (full), and M06-2X methods with the 6-311 + + G(2df,2p) basis set. The order of the responsivity is JO9C > JH14 > JH6 > insensitive RDX. The binding energies follow the order of JH14* ≈ JO9C* < insensitive RDX* < JH6*. The interaction energies and BDEs are in RDX∙∙∙(CHCOOCa) > RDX∙∙∙CHCOOH > RDX∙∙∙CHFCHF. Thus, it can be inferred that for the RDX-based explosives, the stronger the binding energy, intermolecular interaction, and BDE are, the more insensitive the booster is, and thus, the larger energy has to be consumed to overcome the above three kinds of energies during the initiation process, leading to the smaller energy output and weaker response. However, it should be noted that it is mainly the density and the type of explosive that influence the depth of the dent produced on the steel witness block. The essence of the responses to shock waves is revealed by the reduced density gradient, atoms in molecules, and surface electrostatic potentials. HIGHLIGHTS: • Response of booster to shock wave was evaluated by shock wave partition loading test. • Responsivity to shock wave is explained by binding energy, intermolecular interaction, and BDE. • Shock initiation pressures were evaluated. • Essence of responses to shock wave is revealed by RDG, AIM and ESP.
PubMed: 36324010
DOI: 10.1007/s00894-022-05366-7 -
Frontiers in Psychiatry 2018Antipsychotic drugs targeting dopamine neurotransmission are still the principal mean of therapeutic intervention for schizophrenia. However, about one third of people... (Review)
Review
Antipsychotic drugs targeting dopamine neurotransmission are still the principal mean of therapeutic intervention for schizophrenia. However, about one third of people do not respond to dopaminergic antipsychotics. Genome wide association studies (GWAS), have shown that multiple genetic factors play a role in schizophrenia pathophysiology. Most of these schizophrenia risk variants are not related to dopamine or antipsychotic drugs mechanism of action. Genetic factors have also been implicated in defining response to antipsychotic medication. In contrast to disease risk, variation of genes coding for molecular targets of antipsychotics have been associated with treatment response. Among genes implicated, those involved in dopamine signaling mediated by D2-class dopamine receptor, including itself and its molecular effectors, have been implicated as key genetic predictors of response to treatments. Studies have also reported that genetic variation in genes coding for proteins that cross-talk with DRD2 at the molecular level, such as , and are associated with response to antipsychotics. In this review we discuss the relative contribution to antipsychotic drug responsiveness of candidate genes and GWAS identified genes encoding proteins involved in dopamine responses. We also suggest that in addition of these older players, a deeper investigation of new GWAS identified schizophrenia risk genes such as can provide new prospects that are not clearly engaged in dopamine function while being targeted by dopamine-associated signaling molecules. Overall, further examination of genes proximally or distally related to signaling mechanisms engaged by medications and associated with disease risk and/or treatment responsiveness may uncover an interface between genes involved in disease causation with those affecting disease remediation. Such a nexus would provide realistic targets for therapy and further the development of genetically personalized approaches for schizophrenia.
PubMed: 30687136
DOI: 10.3389/fpsyt.2018.00702 -
Frontiers in Plant Science 2022Environmental stress is one of the major restrictions on plant development and foodstuff production. The adaptive response in plants largely occurs through an intricate... (Review)
Review
Environmental stress is one of the major restrictions on plant development and foodstuff production. The adaptive response in plants largely occurs through an intricate signaling system, which is crucial for regulating the stress-responsive genes. Myelocytomatosis (MYC) transcription factors are the fundamental regulators of the jasmonate (JA) signaling branch that participates in plant development and multiple stresses. By binding to the -acting elements of a large number of stress-responsive genes, JA-responsive transcription factors activate the stress-resistant defense genes. The mechanism of stress responses concerns myriad regulatory processes at the physiological and molecular levels. Discovering stress-related regulatory factors is of great value in disclosing the response mechanisms of plants to biotic or abiotic stress, which could guide the genetic improvement of plant resistance. This review summarizes recent researches in various aspects of MYC2-mediated JA signaling and emphasizes MYC2 involvement in plant growth and stress response.
PubMed: 35548315
DOI: 10.3389/fpls.2022.868874 -
Angewandte Chemie (International Ed. in... Jan 2023A design strategy that combines molecular conformation, alkyl chain length, and charge-transfer effects has been developed to obtain conformational and...
A design strategy that combines molecular conformation, alkyl chain length, and charge-transfer effects has been developed to obtain conformational and stacking-adaptable donor-acceptor-π type molecules for precisely regulating the monomer and excimer emission in a single luminous platform under different environments. These fluorophores can exhibit bright monomer emissions when they are in the dispersed state based on their planar conformation. However, when the luminous molecules with short alkyl side chains are in the crystalline state, their molecular conformation can become distorted, further inducing strong intermolecular interactions and staggered π-π stacking for bright excimer emission. More importantly, their dispersed and aggregated states can be reversibly regulated in a phase-change fatty acid matrix, to achieve temperature-responsive fluorescence for temperature monitoring and advanced information encryption.
PubMed: 36399135
DOI: 10.1002/anie.202215652 -
Physical Chemistry Chemical Physics :... Sep 2023In recent years, Pickering emulsifiers have been widely used in various production fields due to their excellent structural stability, biocompatibility and environmental...
In recent years, Pickering emulsifiers have been widely used in various production fields due to their excellent structural stability, biocompatibility and environmental friendliness. For some applications, it is required that the emulsifier can quickly respond to environmental stimuli and control the transition between stable and unstable emulsions. In this paper, we report a novel composite Pickering emulsifier with FeO as the core and magnetic response recognition body, silica as the intermediate protective layer, and chitosan (CS) of different molecular weights to endow solid particles with surface activity and pH-responsive properties. This emulsifier can stabilize the emulsion in the emulsion system with deionized water as the aqueous phase and liquid paraffin as the oil phase and can control the demulsification of the formed emulsion under the dual pH/magnetic stimulation. The experimental results show that FeO@SiO@CS has good paramagnetism and pH responsiveness. The particle size of the composite emulsifier nanoparticles is between 90 nm and 120 nm, and the best stabilizing effect of the emulsion is achieved when the dosage is 0.5 wt%. In the pH range of 3-11, the emulsifier can rapidly demulsify a stable paraffin oil-water emulsion system under the action of a magnetic field of strength 0.4 T. The pH response of the emulsifier is as follows: when pH ≤ 2, the system can form a stable emulsion, which is composed of fully protonated chitosan as a free chain segment and FeO@SiO. Emulsion stabilization was achieved with monolithic FeO@SiO@CS as an emulsifier at pH > 2, and demulsification was achieved at pH ≈ p (CS) at 298 K. The research in this paper can provide a feasible idea and synthesis method for the preparation of organic-inorganic composite structure emulsifier.
PubMed: 37724345
DOI: 10.1039/d3cp03400c -
Frontiers in Plant Science 2023NAC transcription factors are an important genes that regulate plant growth and development, and can regulate functions such as fruit ripening in plants. Based on genome...
NAC transcription factors are an important genes that regulate plant growth and development, and can regulate functions such as fruit ripening in plants. Based on genome data of , the gene family was identified and analyzed by bioinformatics methods. In this study, we identified 85 genes in genome, and systematically analyzed the gene family. We found that they were distributed unevenly in the nineteen chromosomes. The amino acid length of gene family () ranged from 80 to 1065, molecular weight ranged from 22.17 to 119.02 kD, and isoelectric point ranged from 4.61~9.26. Its promoter region contains multiple stress responsive elements, including light responsive, gibberellin-responsive, abscisic acid responsiveness, MeJA-responsiveness and drought-inducibility elements. Phylogenetic analysis indicates that the gene family is most closely related to and . Analysis of SSR loci indicates that the fraction of mononucleotide repeats was the largest, as was the frequency of A/T. Non-coding RNA analysis showed that these 85 genes contain 397 miRNAs. The collinearity analysis shows that 9 collinear locis were found on the chromosomes of with , and 75 collinear locis with QRT-PCR experiment under different salt concentration and temperature conditions verified the response mechanism of gene family under stress conditions. Most genes are sensitive to salt stress and temperature stress. The results of this study provide a reference for further understanding the function of gene in .
PubMed: 37670854
DOI: 10.3389/fpls.2023.1232804 -
Frontiers in Immunology 2023Natural Killer (NK) cells contribute to the protective effects of vaccine-induced antibodies thanks to the low affinity receptor for IgG, FcγRIIIA/CD16, whose...
INTRODUCTION
Natural Killer (NK) cells contribute to the protective effects of vaccine-induced antibodies thanks to the low affinity receptor for IgG, FcγRIIIA/CD16, whose aggregation leads to the killing of infected cells and IFNγ release, through which they potentiate adaptive immune responses.
METHODS
Forty-seven healthy young individuals undergoing either homologous (ChAdOx1-S/ChAdOx1-S) or heterologous (ChAdOx1-S/BNT162B2) SARS-CoV-2 vaccination settings were recruited. Peripheral blood samples were collected immediately prior to vaccination and 8 weeks after the booster dose. The phenotypic and functional profile of NK cells was evaluated by flow cytometry at both time points. Serum samples were tested to evaluate circulating anti-Spike IgG levels and cytomegalovirus serostatus. CD16 F158V polymorphism was assessed by sequencing analysis.
RESULTS
The downregulation of CD16 and the selective impairment of antibody-dependent cytotoxicity and IFNγ production in CD56 NK population, persisting 8 weeks after boosting, were observed in heterologous, but not in homologous SARS-CoV-2 vaccination scheme. While the magnitude of CD16-dependent functions of the global CD56 pool correlated with receptor levels before and after vaccination, the responsivity of NKG2C subset, that displays amplified size and functionality in HCMV individuals, resulted intrinsically insensitive to CD16 levels. Individual CD16 responsiveness was also affected by CD16F158V polymorphism; F/F low affinity individuals, characterized by reduced CD16 levels and functions independently of vaccination, did not show post-vaccinal functional impairment with respect to intermediate and high affinity ones, despite a comparable CD16 downregulation. Further, CD16 high affinity ligation conditions by means of afucosylated mAb overcame vaccine-induced and genotype-dependent functional defects. Finally, the preservation of CD16 expression directly correlated with anti-Spike IgG titer, hinting that the individual magnitude of receptor-dependent functions may contribute to the amplification of the vaccinal response.
CONCLUSION
This study demonstrates a durable downmodulation of CD16 levels and Ab-dependent NK functions after SARS-CoV-2 heterologous vaccination, and highlights the impact of genetic and environmental host-related factors in modulating NK cell susceptibility to post-vaccinal Fc-dependent functional impairment.
Topics: Humans; COVID-19 Vaccines; SARS-CoV-2; Antibody-Dependent Cell Cytotoxicity; BNT162 Vaccine; COVID-19; Killer Cells, Natural; Antibodies, Viral; Vaccination; Immunoglobulin G
PubMed: 38045702
DOI: 10.3389/fimmu.2023.1285203 -
Open Biology Apr 2018The endoplasmic reticulum (ER) stress response is regarded as an important process in the aetiology of Alzheimer's disease (AD). The accumulation of pathogenic misfolded... (Review)
Review
The endoplasmic reticulum (ER) stress response is regarded as an important process in the aetiology of Alzheimer's disease (AD). The accumulation of pathogenic misfolded proteins and the disruption of intracellular calcium (Ca) signalling are considered to be fundamental mechanisms that underlie the induction of ER stress, leading to neuronal cell death. Indeed, a number of studies have proposed molecular mechanisms linking ER stress to AD pathogenesis based on results from systems and AD mouse models. However, stress responsivity was largely different between each mouse model, even though all of these models display AD-related pathologies. While several reports have shown elevated ER stress responses in amyloid precursor protein (APP) and presenilin 1 (PS1) double-transgenic (Tg) AD mouse models, we and other groups, in contrast, observed no such ER stress response in APP-single-Tg or -knockin mice. Therefore, it is debatable whether the ER stress observed in APP and PS1 double-Tg mice is due to AD pathology. From these findings, the roles of ER stress in AD pathogenesis needs to be carefully addressed in future studies. In this review, we summarize research detailing the relationship between ER stress and AD, and analyse the results in detail.
Topics: Alzheimer Disease; Amyloid beta-Protein Precursor; Animals; Calcium Signaling; Endoplasmic Reticulum Stress; Mice; Mice, Transgenic; Models, Molecular; Protein Folding
PubMed: 29695619
DOI: 10.1098/rsob.180024