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Developing tough adhesives with superior strength and ductility is challenging yet highly sought-after. In this work, we address a strategic approach to achieving diverse toughness and performance by meticulously harnessing weak electrostatic interactions. Two polyzwitterions (PZIs), derived from sulfobetaine methacrylate (SBMA), of different topologies: bottlebrush (BB-PSBMA) and linear (L-PSBMA), were designed. BB-PSBMA was synthesized using a rational "grafting-from" strategy, while L-PSBMA was prepared via atom transfer radical polymerization. Despite their architectural disparities, both PZIs demonstrated a comparable substantial lap-shear adhesion strength of â¼0.4 MPa. Intriguingly, the introduction of NaCl during adhesive preparation revealed contrasting adhesion behaviors. BB-PSBMA transitioned from a strong-brittle to strong-ductile adhesive upon the addition of 70 mM NaCl, evidenced by a 77.4% increase in the work of debonding, i.e., toughness. Further increases in NaCl concentration continued to impart the ductile properties to BB-PSBMA. Conversely, L-PSBMA adhesive predominantly transformed from strong-brittle to ductile regardless of the salt content. We propose a synergistic mechanism involving viscosity-governed optimal adhesion-cohesion balance and mechanical energy dissipation through sacrificial electrostatic association to elucidate the strong and ductile nature of the BB-PSBMA adhesive at 70 mM NaCl. Our findings emphasize the significance of precise control over architecture and salt concentration is necessary in constructing adhesives with enhanced toughness and performance.
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Achieving efficient and site-specific conjugation of therapeutic protein to polymer is crucial to augment their applicability in the realms of biomedicine by improving their stability and enzymatic activity. In this study, we exploited tetrazine bioorthogonal chemistry to achieve the site-specific conjugation of bottlebrush polymers to urate oxidase (UOX), a therapeutic protein for gout treatment. An azido-functionalized zwitterionic bottlebrush polymer (N3-ZBP) using a "grafting-from" strategy involving RAFT and ATRP methods was synthesized, and a trans-cyclooctene (TCO) moiety was introduced at the polymer end through the strain-promoted azide-alkyne click (SPAAC) reaction. The subsequent coupling between TCO-incorporated bottlebrush polymer and tetrazine-labeled UOX using a fast and safe bioorthogonal reaction, inverse electron demand Diels-Alder (IEDDA), led to the formation of UOX-ZBP conjugates with a 52% yield. Importantly, the enzymatic activity of UOX remained unaffected following polymer conjugation, suggesting a minimal change in the folded structure of UOX. Moreover, UOX-ZBP conjugates exhibited enhanced proteolytic resistance and reduced antibody binding, compared to UOX-wild type. Overall, the present findings reveal an efficient and straightforward route for synthesizing protein-bottlebrush polymer conjugates without compromising the enzymatic activity while substantially reducing proteolytic degradation and antibody binding.
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Química Click , Reação de Cicloadição , Polímeros , Urato Oxidase , Urato Oxidase/química , Química Click/métodos , Polímeros/química , Ciclo-Octanos/química , Humanos , Azidas/química , Alcinos/químicaRESUMO
We present a straightforward strategy for constructing giant, multicompartmentalized vesicles using recombinant fusion proteins. Our method leverages the self-assembly of globule-zipper-elastin-like polypeptide fusion protein complexes in aqueous conditions, eliminating the need for organic solvents and chemical conjugation. By employing the thin-film rehydration method, we have successfully encapsulated a diverse range of bioactive macromolecules and engineered organelle-like compartmentsâranging from soluble proteins and coacervate droplets to vesiclesâwithin these protein-assembled giant vesicles. This approach also facilitates the integration of water-soluble block copolymers, enhancing the structural stability and functional versatility of the vesicles. Our results suggest that these multicompartment giant protein vesicles not only mimic the complex architecture of living cells but also support biochemically distinct reactions regulated by functionally folded proteins, providing a robust model for studying cellular processes and designing microreactor systems. This work highlights the transformative potential of self-assembling recombinant fusion proteins in artificial cell design.
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Atopic dermatitis (AD) is a relapsing skin disease with persistent inflammation as a causal factor for symptoms and disease progression. Current therapies provide only temporary relief and require long-term usage accompanied by side effects due to persistent relapses. A short peptide, TPS240, has been tested for its potential to subside AD. In this study, we confirmed the anti-atopic effect of TPS240 in vivo and in vitro using a DNCB-induced AD mouse model and TNF-α/IFN-γ-stimulated HaCaT cells. In the AD mouse model, topical treatment with TPS240 diminished AD-like skin lesions and symptoms such as epidermal thickening and mast cell infiltration induced by DNCB, similar to the existing treatment, dexamethasone (Dex). Furthermore, skin atrophy, weight loss, and abnormal organ weight changes observed in the Dex-treated group were not detected in the TPS240-treated group. In TNF-α/IFN-γ-stimulated HaCaT cells, TPS240 reduced the expression of the inflammatory chemokines CCL17 and CCL22 and the pruritic cytokines TSLP and IL-31 by inhibiting NF-κB and STAT3 activation. These results suggest that TPS240 has an anti-atopic effect through immunomodulation of AD-specific cytokines and chemokines and can be used as a candidate drug for the prevention and treatment of AD that can solve the safety problems of existing treatments.
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Dermatite Atópica , NF-kappa B , Animais , Camundongos , NF-kappa B/metabolismo , Dermatite Atópica/induzido quimicamente , Dermatite Atópica/tratamento farmacológico , Dermatite Atópica/patologia , Queratinócitos/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Dinitroclorobenzeno/farmacologia , Linhagem Celular , Citocinas/metabolismo , Quimiocinas/metabolismo , Pele/metabolismo , Camundongos Endogâmicos BALB CRESUMO
Parnassius bremeri (P. bremeri), a member of the genus Snow Apollo in the swallowtail family (Papilionidae), is a high alpine butterfly that lives in Russia, Korea, and China. It is an endangered wildlife (Class I) in South Korea and is a globally endangered species. The lack of transcriptomic and genomic resources of P. bremeri significantly hinders the study of its population genetics and conservation. The detailed information of the developmental stage-specific gene expression patterns of P. bremeri is of great demand for its conservation. However, the molecular mechanism underlying the metamorphic development of P. bremeri is still unknown. In the present study, the differentially expressed genes (DEGs) across the metamorphic developmental stages were compared using high-throughput transcriptome sequencing. We identified a total of 72,161 DEGs from eight comparisons. GO enrichment analysis showed that a range of DEGs were responsible for cuticle development and the melanin biosynthetic pathway during larval development. Pathway analysis suggested that the signaling pathways, such as the Wnt signaling pathway, hedgehog signaling pathway and Notch signaling pathway, are regulated during the developmental stages of P. bremeri. Furthermore, sensory receptors were also activated, especially during the larval to adult transition stage. Collectively, the results of this study provide a preliminary foundation and understanding of the molecular mechanism in their transcriptomes for further research on the metamorphic development of P. bremeri.
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Borboletas , Animais , Borboletas/genética , Perfilação da Expressão Gênica , Proteínas Hedgehog/genética , Melaninas/genética , TranscriptomaRESUMO
Cytochrome P450 3A5 (CYP3A5) is one of the crucial CYP family members and has already proven to be an important drug target for cardiovascular diseases. In the current study, the PubChem database was screened through molecular docking and high-affinity molecules were adopted for further assessment. A negative image-based (NIB) model was used for a similarity search by considering the complementary shape and electrostatics of the target and small molecules. Further, the molecules were segregated into active and inactive groups through six machine learning (ML) matrices. The active molecules found in each ML model were used for in silico pharmacokinetics and toxicity assessments. A total of five molecules followed the acceptable pharmacokinetics and toxicity profiles. Several potential binding interactions between the proposed molecules and CYP3A5 were observed. The dynamic behavior of the selected molecules in the CYP3A5 was explored through a molecular dynamics (MD) simulation study. Several parameters obtained from the MD simulation trajectory explained the stability of the protein-ligand complexes in dynamic states. The high binding affinity of each molecule was revealed by the binding free energy calculation through the MM-GBSA methods. Therefore, it can be concluded that the proposed molecules might be potential CYP3A5 molecules for therapeutic application in cardiovascular diseases subjected to in vitro/in vivo validations.
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Doenças Cardiovasculares , Inibidores do Citocromo P-450 CYP3A , Simulação de Dinâmica Molecular , Citocromo P-450 CYP3A/metabolismo , Inibidores do Citocromo P-450 CYP3A/química , Humanos , Aprendizado de Máquina , Simulação de Acoplamento MolecularRESUMO
Lignin is an aromatic-rich biomass polymer that is cheap, abundant, and sustainable. However, its application in the solid electrolyte field is rare due to challenges in well-defined polymer synthesis. Herein, the synthesis of lignin-graft-poly(ethylene glycol) (PEG) and its conductivity test for a solid electrolyte application are demonstrated. The main steps of synthesis include functionalization of natural lignin's hydroxyl to alkene, followed by graft-copolymerization of PEG thiol to the lignin via photoredox thiol-ene reaction. Two lignin-graft-PEGs are prepared having 22 wt% lignin (lignin-graft-PEG 550) and 34 wt% lignin (lignin-graft-PEG 2000). Then, new polymer electrolytes for conductivity tests are prepared via addition of lithium bis-trifluoromethanesulfonimide. The polymer graft electrolytes exhibit ionic conductivity up to 1.4 × 10-4 S cm-1 at 35 °C. The presence of lignin moderately impacts conductivity at elevated temperature compared to homopolymer PEG. Furthermore, the ionic conductivity of lignin-graft-PEG at ambient temperature is significantly higher than homopolymer PEG precedents.
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Polietilenoglicóis , Polímeros , Eletrólitos , Lignina , LítioRESUMO
Drought is one of the major environmental stresses adversely affecting crop productivity worldwide. Precise characterization of genes involved in drought response is necessary to develop new crop varieties with enhanced drought tolerance. Previously, we identified 66 drought-induced miRNAs in rice plants. For the further functional investigation of the miRNAs, we applied recombinant codon-optimized Cas9 (rCas9) for rice with single-guide RNAs specifically targeting mature miRNA sequences or sites required for the biogenesis of mature miRNA. A total of 458 T0 transgenic plants were analyzed to determine the frequency and type of mutations induced by CRISPR/rCas9 on 13 independent target miRNAs. The average mutation frequency for 13 genes targeted by single guide RNAs (sgRNAs) in T0 generation was 59.4%, including mono-allelic (8.54%), bi-allelic (11.1%), and hetero-allelic combination (39.7%) mutations. The mutation frequency showed a positive correlation with Tm temperature of sgRNAs. For base insertion, one base insertion (99%) was predominantly detected in transgenic plants. Similarly, one base deletion accounted for the highest percentage, but there was also a significant percentage of cases in which more than one base was deleted. The deletion of more than two bases in OsmiR171f and OsmiR818b significantly reduced the level of corresponding mature miRNAs. Further functional analysis using CRISPR/Cas9-mediated mutagenesis confirmed that OsmiR818b is involved in drought response in rice plants. Overall, this study suggests that the CRISPR/rCas9 system is a powerful tool for loss-of-function analysis of miRNA in rice.
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Sistemas CRISPR-Cas , Edição de Genes/métodos , MicroRNAs/genética , Oryza/genética , Melhoramento Vegetal/métodos , Secas , Oryza/fisiologia , Estresse FisiológicoRESUMO
A study of reaction kinetics and removal efficiency of a family of ruthenium (Ru)-based olefin metathesis catalysts containing ethylene-glycol-oligomer-tethered N-heterocyclic carbene (NHC) ligands has been carried out, with a focus on variation of ethylene glycol oligomer length. The length of ethylene glycol oligomer was precisely defined by sequential addition of repeating units. Due to the dual solubility of ethylene glycol oligomer, the produced catalyst was highly soluble in both aqueous and organic solvents (dichloromethane). In aqueous solution, the polarity increase with longer ethylene glycol oligomers enhanced the reactivity in homogeneous solution. The length of ethylene glycol oligomer did not significantly affect olefin metathesis rate in organic solution. Yet the removal efficiency of catalyst strongly relies on the length of ethylene glycol oligomer. A longer ethylene glycol oligomer demonstrated better catalyst removal efficiency. The tested catalyst removal method was aqueous extraction from organic solution using its higher water solubility property compared to its lower organic solvent (dichloromethane) solubility property. The results obtained from the aqueous extraction catalyst removal method demonstrated similar and/or better removal rates compared to previously reported host-guest catalyst removal methods.
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A new terpolymer adhesive, poly(2-methoxyethyl acrylate-co-N-methacryloyl 3,4-dihydroxyl-l-phenylalanine-co-heptaisobutyl substituted polyhedral oligomeric silsesquioxane propyl methacrylate) (poly(MEA-co-MDOPA-co-MPOSS) was synthesized by thermally initiated radical polymerization. In this study, we investigated the effect of the POSS component on adhesion, mechanical, and optical properties of the catechol-group containing bioinspired adhesives. The terpolymer contains the catechol group which is known to improve the adhesion properties of polymers. Only a very small amount of the POSS-containing monomer, MPOSS, was included, 0.5 mol %. In the presence of POSS, the synthesized poly(MEA-co-MDOPA-co-MPOSS) demonstrated strong adhesion properties, 23.2 ± 6.2 J/m2 with 0.05 N preloading and 300 s holding time, compared to many previously prepared catechol-containing adhesives. The mechanical properties (Young's modulus and stress at 10% strain) of the POSS-containing terpolymer showed significant increases (6-fold higher) over the control polymer, which does not contain POSS. Optical transmittance of the synthesized terpolymer was also improved significantly in the visible light range, 450-750 nm. Cell testing with human embryonic kidney cells (HEK293A) indicates that the new terpolymer is a promising candidate in biomedical adhesives without acute cytotoxicity. The synthesized poly(MEA-co-MDOPA-co-MPOSS) is the first example of POSS-containing pressure sensitive bioinspired adhesive for biomedical applications. The study of poly(MEA-co-MDOPA-co-MPOSS) demonstrated a convenient method to enhance two important properties, mechanical and optical properties, by the addition of a very small amount of POSS. Based on this study, it was found that POSS can be used to strengthen mechanical properties of bioinspired adhesive without the need for a covalent cross-linking step.
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Adesivos/química , Metacrilatos/química , Compostos de Organossilício/química , Polímeros/química , Proliferação de Células , Módulo de Elasticidade , Células HEK293 , Humanos , Teste de Materiais , Fenômenos Ópticos , Polimerização , Estresse Mecânico , Propriedades de SuperfícieRESUMO
In this study, an innovative and cost-effective ionic polymer for CO2 capture and utilization for the first time, using abundant and nonfood-based biomass lignin is reported. The modified ionic polymer synthesizes through the reaction of glycidyltrimethylammonium chloride with lignin under alkaline conditions to yield quaternary ammonium ionic functionality. Subsequently, the hydroxide-based pure ionic lignin polymer is employed for CO2 capture from both direct air and concentrated CO2 sources at room temperature and atmospheric pressure. Structural characterization of the polymers is accomplished through 1H, 13C, and 2D-heteronuclear single quantum coherence (HSQC) NMR, and FT-IR spectroscopy. The CO2 capture process is established through the formation of bicarbonate ions alongside the presence of CO2. The captured CO2 is precisely quantified by using inverse-gated proton decoupled 13C NMR with an internal standard (trioxane). Remarkably, the captured-CO2 amounts of ionic lignin polymer are 1.06 mmol g-1 (47 mg g-1) from concentrated-CO2 source and 0.60 mmol g-1 (26 mg g-1) from direct-air. The captured-CO2 in ionic lignin polymer is released in controlled manner and utilized in the synthesis of cyclic carbonate, showcasing the productive application of the captured carbon. Moreover, the fully controlled recovering of ionic lignin polymer achieves via repeated CO2 release â CO2 capture.
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The PI3K/AKT/FOXO3 pathway is one of the most frequently involved signaling pathways in cancer, including breast cancer. Therefore, we synthesized a novel lysine-rich polypeptide (Lys-PP) using de novo assembly method and evaluated its anticancer effect. We characterized the structural and physicochemical properties of Lys-PP using various techniques. Later, we used integrated approaches such as in silico, in vitro, and in vivo analysis to confirm the anticancer and therapeutic effect of Lys-PP. First, RNA sequencing suggests Lys-PP disrupted the central carbon metabolic pathway through the modulation of prolactin signaling. Additionally, docking analysis also confirmed the significant association of PI3K/AKT and FOXO3 pathway to induce an apoptotic effect on cancer. Second, Lys-PP exhibited a significant cytotoxicity effect against MDA-MB-231 but no cytotoxic effects on RAW 264.7 and HEK-293, respectively. The cytotoxic effect of Lys-PP-induced apoptosis by an increase in FOXO3a protein expression and a decrease in PI3K/AKT pathway was confirmed by quantitative real-time polymerase chain reaction, immunoblotting, and fluorescent microscopy. Later, immunohistochemistry and hematoxylin and eosin staining on MDA-MD-231 showed increased FOXO3a expression and cell death in the xenograft mice model. Further, liver function, metabolic health, or lipid profile upon Lys-PP showed the absence of significant modulation in the biomarkers except for kidney-related biomarkers. Overall, our comprehensive study provides the first evidence of Lys-PP antibreast cancer action, which could serve as a potential treatment in an alternative or complementary medicine practice.
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Atopic dermatitis (AD) is a chronic inflammatory skin disease which requires continuous treatment due to its relapsing nature. The current treatment includes steroids and nonsteroidal agents targeting inflammation but long-term administration causes various side effects such as skin atrophy, hirsutism, hypertension and diarrhea. Thus, there is an unmet need for safer and effective therapeutic agents in the treatment of AD. Peptides are small biomolecule drugs which are highly potent and remarkably have less side effects. Parnassin is a tetrapeptide with predicted anti-microbial activity curated from Parnassius bremeri transcriptome data. In this study, we confirmed the effect of parnassin on AD using a DNCB-induced AD mouse model and TNF-α/IFN-γ-stimulated HaCaT cells. In the AD mouse model, topical administration of parnassin improved skin lesions and symptoms in AD mice, such as epidermal thickening and mast cell infiltration, similar to the existing treatment, dexamethasone, and did not affect body weight, or the size and weight of spleen. In TNF-α/IFN-γ-stimulated HaCaT cells, parnassin inhibited the expression of Th2-type chemokine CCL17 and CCL22 genes by suppressing JAK2 and p38 MAPK signaling kinases and their downstream transcription factor STAT1. Parnassin also significantly reduced the gene expression of TSLP and IL-31, which are pruritus-inducing cytokines. These findings suggested that parnassin alleviates AD-like lesions via its immunomodulatory effects and can be used as a candidate drug for the prevention and treatment of AD because it is safer than existing treatments.
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The rupture of macrophage phagosomes has been implicated in various human diseases and plays a critical role in immunity. However, the mechanisms underlying this process are complex and not yet fully understood. This study describes the development of a robust engineering method for rupturing phagosomes based on a well-defined mechanism. The method utilizes microfabricated microparticles composed of uncrosslinked linear poly(N-isopropylacrylamide) (PNIPAM) as phagocytic objects. These microparticles are internalized into phagosomes at 37 °C. By exposing the cells to a cold shock at 0 °C, the vast majority of the microparticle-containing phagosomes rupture. The percentage of phagosomal rupture decreases with the increase of the cold-shock temperature. The osmotic pressure in the phagosomes and the tension in the phagosomal membrane are calculated using the Flory-Huggins theory and the Young-Laplace equation. The modeling results indicate that the osmotic pressure generated by dissolved microparticles is probably responsible for phagosomal rupture, are consistent with the experimentally observed dependence of phagosomal rupture on the cold-shock temperature, and suggest the existence of a cellular mechanism for resisting phagosomal rupture. Moreover, the effects of various factors including hypotonic shock, chloroquine, tetrandrine, colchicine, and l-leucyl-l-leucine O-methyl ester (LLOMe) on phagosomal rupture have been studied with this method. The results further support that the osmotic pressure generated by the dissolved microparticles causes phagosomal rupture and demonstrated usefulness of this method for studying phagosomal rupture. This method can be further developed, ultimately leading to a deeper understanding of phagosomal rupture.
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Macrófagos , Fagossomos , HumanosRESUMO
Physiological response and transcriptome changes were observed to investigate the effects on the growth, metabolism and genetic changes of Pinus densiflora grown for a long time in an environment with an elevated atmospheric CO2 concentration. Pine trees were grown at ambient (400 ppm) and elevated (560 ppm and 720 ppm) CO2 concentrations for 10 years in open-top chambers. The content of nonstructural carbohydrates was significantly increased in elevated CO2. It was notable that the contents of chlorophylls significantly decreased at an elevated CO2. The activities of antioxidants were significantly increased at an elevated CO2 concentration of 720 ppm. We analyzed the differences in the transcriptomes of Pinus densiflora at ambient and elevated CO2 concentrations and elucidated the functions of the differentially expressed genes (DEGs). RNA-Seq analysis identified 2415 and 4462 DEGs between an ambient and elevated CO2 concentrations of 560 ppm and 720 ppm, respectively. Genes related to glycolysis/gluconeogenesis and starch/sucrose metabolism were unchanged or decreased at an elevated CO2 concentration of 560 ppm and tended to increase at an elevated CO2 concentration of 720 ppm. It was confirmed that the expression levels of genes related to photosynthesis and antioxidants were increased at an elevated CO2 concentration of 720 ppm.
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Phagocytosis performed by a macrophage involves complex membrane trafficking and reorganization among various membranous cellular structures including phagosomes and vesicles derived from the phagosomes known as phagosome-derived vesicles. The present work reports on development of a technique that allows to specifically label the phagosome-derived vesicles in macrophages with a membrane dye. The technique is based on the use of microfabricated microparticles that are made of a thermosensitive nonbiodegradable polymer poly(N-isopropylacrylamide) (PNIPAM) or its derivative and contain a membrane dye 1,1'-dialkyl-3,3,3',3'-tetramethylindodicarbocyanine (DiI). The microparticles can be phagocytosed by RAW264.7 macrophages into their phagosomes, resulting in formation of intracellular DiI-positive vesicles derived from the phagosomes. The DiI-positive vesicles are motile and acidic; can be stained by fluorescently labelled dextran added in the culture medium; and can accumulate around new phagosomes, indicating that they possess properties of lysosomes. This technique is also applicable to another membrane dye 3,3'-dioctadecyloxacarbocyanine (DiO) and holds great potential to be useful for advancing our understanding of phagocytosis. STATEMENT OF SIGNIFICANCE: Phagocytosis performed by macrophages is a cellular process of great importance to various applications of biomaterials such as drug delivery and medical implantation. This work reports on a technique for characterizing phagocytosis based on the use of poly(N-isopropylacrylamide), which is a major biomaterial with numerous applications. This technique is the first of its kind and has generated an original finding about phagocytosis. In addition to drug delivery and medical implantation, phagocytosis plays critical roles in diseases, injuries and vaccination. This work could thus attract immediate and widespread interests in the field of biomaterials science and engineering.
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Fagocitose , Fagossomos , Materiais Biocompatíveis , Lisossomos , MacrófagosRESUMO
We present a study on the effects of cross-linking on the adhesive properties of bio-inspired 3,4-dihydroxyphenylalanine (DOPA). DOPA has a unique catechol moiety found in adhesive proteins in marine organisms, such as mussels and polychaete, which results in strong adhesion in aquatic conditions. Incorporation of this functional group in synthetic polymers provides the basis for pressure-sensitive adhesives for use in a broad range of environments. A series of cross-linked DOPA-containing polymers were prepared by adding divinyl cross-linking agent ethylene glycol dimethacrylate (EGDMA) to monomer mixtures of dopamine methacrylamide (DMA) and 2-methoxyethyl acrylate (MEA). Samples were prepared using a solvent-free microwave-assisted polymerization reaction and compared to a similar series of cross-linked MEA materials. Cross-linking with EGDMA tunes the viscoelastic properties of the adhesive material and has the advantage of not reacting with the catechol group that is responsible for the excellent adhesive performance of this material. Adhesion strength was measured by uniaxial indentation tests, which indicated that 0.001 mol % of EGDMA-cross-linked copolymer showed the highest work of adhesion in dry conditions, but non-cross-linked DMA was the highest in wet conditions. The results suggest that there is an optimal cross-linking degree that displays the highest adhesion by balancing viscous and elastic behaviors of the polymer but this appears to depend on the conditions. This concentration of cross-linker is well below the theoretical percolation threshold, and we propose that subtle changes in polymer viscoelastic properties can result in significant improvements in adhesion of DOPA-based materials. The properties of lightly cross-linked poly(DMA-co-MEA) were investigated by measurement of the frequency dependence of the storage modulus (G') and loss modulus (G''). The frequency-dependence of G' and magnitude of G'' showed gradual decreases with the fraction of EGDMA. Loosely cross-linked DMA copolymers, containing 0% and 0.001 mol % of EGDMA-cross-linked copolymers, displayed rheological behavior appropriate for pressure-sensitive adhesives characterized by a higher G' at high frequencies and lower G' at low frequencies. Our results indicate that dimethacrylate cross-linking of DMA copolymers can be used to enhance the adhesive properties of this unique material.
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Acrilamidas/química , Adesivos/química , Dopamina/química , Substâncias Viscoelásticas/química , Acrilatos/química , Metacrilatos/química , Polímeros/síntese química , Polímeros/química , Propriedades de SuperfícieRESUMO
Fleshy fruits are the most demanded fruits because of their organoleptic qualities and nutritional values. The genus Prunus is a rich source of diversified stone/drupe fruits such as almonds, apricots, plums, sweet cherries, peaches, and nectarines. The fruit-ripening process in Prunus involves coordinated biochemical and physiological changes resulting in changes in fruit texture, aroma gain, color change in the pericarp, sugar/organic acid balance, fruit growth, and weight gain. There are different varieties of peaches with unique palatable qualities and gaining knowledge in the genetics behind these quality traits helps in seedling selection for breeding programs. In addition, peaches have shorter post-harvest life due to excessive softening, resulting in fruit quality reduction and market loss. Many studies have been executed to understand the softening process at the molecular level to find the genetic basis. To summarize, this review focused on the molecular aspects of peach fruit quality attributes and their related genetics to understand the underlying mechanisms.
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The stem and root bark of Ulmus macrocarpa Hance has been used as traditional pharmacological agent against inflammation related disorders. The objective of this study was to explore the impact of Ulmus macrocarpa Hance extract (UME) on human gut microbiota. A randomized placebo-controlled clinical study was conducted in healthy adults. The study subjects were given 500 mg/day of UME or placebo orally for 4 weeks. Eighty fecal samples were collected at baseline and 4 weeks of UME or placebo intervention. The gut microbiota variation was evaluated by 16S rRNA profiling. The microbial response was highly personalized, and no statistically significant differences was observed in both species richness and abundance. The number of bacterial species identified in study subjects ranged from 86 to 182 species. The analysis for taxonomical changes revealed an increase in Eubacterium ventriosum, Blautia faecis, Ruminococcus gnavus in the UME group. Functional enrichment of bacterial genes showed an increase in primary and secondary bile acid biosynthesis in UME group. Having known from previous studies Eubacterium regulated bile acid homeostasis in protecting gut microbial architecture and immunity, we suggest that UME supplementation might enhance host immunity by modulating gut microbiota. This is the first stage study and forthcoming clinical studies with larger participants are needed to confirm these findings.
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Microbioma Gastrointestinal , Extratos Vegetais/farmacologia , Ulmus , Adulto , Bactérias/classificação , Bactérias/crescimento & desenvolvimento , Método Duplo-Cego , Fezes/microbiologia , Feminino , Humanos , Masculino , Extratos Vegetais/administração & dosagem , RNA Ribossômico 16S/genéticaRESUMO
In plants, glyceraldehyde-3-phosphate dehydrogenase (GAPDH) is a main enzyme in the glycolytic pathway. It plays an essential role in glycerolipid metabolism and response to various stresses. To examine the function of PsGAPDH (Pleurotus sajor-caju GAPDH) in response to abiotic stress, we generated transgenic rice plants with single-copy/intergenic/homozygous overexpression PsGAPDH (PsGAPDH-OX) and investigated their responses to salinity stress. Seedling growth and germination rates of PsGAPDH-OX were significantly increased under salt stress conditions compared to those of the wild type. To elucidate the role of PsGAPDH-OX in salt stress tolerance of rice, an Illumina HiSeq 2000 platform was used to analyze transcriptome profiles of leaves under salt stress. Analysis results of sequencing data showed that 1124 transcripts were differentially expressed. Using the list of differentially expressed genes (DEGs), functional enrichment analyses of DEGs such as Gene Ontology (GO) terms and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways were performed. KEGG pathway enrichment analysis revealed that unigenes exhibiting differential expression were involved in starch and sucrose metabolism. Interestingly, trehalose-6-phosphate synthase (TPS) genes, of which expression was enhanced by abiotic stress, showed a significant difference in PsGAPDH-OX. Findings of this study suggest that PsGAPDH plays a role in the adaptation of rice plants to salt stress.