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There is a growing demand for biomaterials developing with novel properties for biomedical applications hence, hydrogels with 3D crosslinked polymeric structures obtained from natural polymers have been deeply inspected in this field. Pectin a unique biopolymer found in the cell walls of fruits and vegetables is extensively used in the pharmaceutical, food, and textile industries due to its ability to form a thick gel-like solution. Considering biocompatibility, biodegradability, easy gelling capability, and facile manipulation of pectin-based biomaterials; they have been thoroughly investigated for various potential biomedical applications including drug delivery, wound healing, tissue engineering, creation of implantable devices, and skin-care products.Quinoa starch granular structure as affected by nonenyl succinic anhydride (NSA) substitution was investigated by multiple approaches, including scattering, spectroscopic, and microscopic techniques. The modification had little impact on the morphology of starch granules. The NSA substitution was found mainly in the amorphous lamellae and amorphous growth rings. The NSA modification increased the thickness of the amorphous lamellae. The homogeneity of the ordered structure in the granules was improved, probably because the NSA modification reduced the amount of defects in the semi-crystalline growth ring. Compared to other chemical modifications such as acylation, succinylation was more effective in modifying the starch lamellar structure. A possible reaction pattern of NSA modification on quinoa starch is proposed, in which the NSA modification may follow the sequence of amorphous growth rings, the amorphous matrices among blocklets, amorphous and crystalline lamellae in semi-crystalline growth rings. This study provides new insights on the structural changes of starch granules induced by succinylation on the supramolecular level.The lysine (K) tRNA synthetase C-terminal (KTSC) domain containing proteins are widely spread in Bacteria, Archaea and Viruses, but the function of this short domain is unclear. The occurrence of the fusion of KTSC domain to a catalytic domain or domains related to DNA or RNA metabolisms suggests its potential role in DNA or RNA binding. Here, we report the characterization of Mvu8s from Methanolobus vulcani, which consists of a single KTSC domain. Mvu8s binds specifically to ssDNA with an affinity approximately 40- and 10-fold higher than those for dsDNA and ssRNA in vitro, respectively. It shows a slight preference to the G-rich DNA sequence but barely binds the A-stretch. Crystal structure of Mvu8s shows that it forms a homo-tetramer, with each monomer composed of a four-strand antiparallel β-sheet and a helix-turn-helix in the order of β1-β2-β3-α1-α2-β4. Four basic residues (R3, R7, K54 and K58) were found to serve important roles in ssDNA-binding. And, the spiral arrangement of the DNA interfaces in Mvu8s homo-tetramer presumably results in ssDNA wrapping. Our results not only offer clues of the functions of the KTSC domain containing proteins but also expand our knowledge on the non-oligonucleotide-binding (OB) fold single-stranded DNA-binding proteins in Archaea.Pectin has recently attracted increasing attention as an alternative biomaterial commonly used in biomedical and pharmaceutical fields. It shows several promising properties, including good biocompatibility, health benefits, nontoxicity, and biodegradation. In this research, novel nanocomposite fibers composed of folic acid-decorated carbon dots (CDs) in pectin/PEO matrix were fabricated using the electrospinning technique, which was never reported previously. Nitrogen-doped and nitrogen, sulfur-doped CDs were synthesized with average diameters of 2.74 nm and 2.17 nm using the one-step hydrothermal method, studied regarding their physicochemical, optical, and biocompatibility properties. The relative Quantum yields of N-CDs and N, S doped CDs were measured to be 54.7 % and 30.2 %, respectively. Nanocomposite fibers containing CDs were prepared, and their morphology, physicochemical properties, conductivity, drug release behavior, and cell viability were characterized. The results indicated that CDs improve fibrous scaffolds’ tensile strength from 13.74 to 35.22 MPa while maintaining comparable extensibility. Furthermore, by incorporation of CDs in the prepared fibers conductivity enhanced from 8.69 × 10-9 S·m-1 to 1.36 × 10-4 S·m-1. The nanocomposite fibrous scaffold was also biocompatible with controlled drug release over 212 h, potentially promising tissue regeneration.Chemo-photothermal therapy is one of the emerging therapies for treating triple-negative breast cancer. In this study, we have used ionotropic gelation method to fabricate chitosan and IR806 dye-based polyelectrolyte complex (CIR-PEx) nanoparticles. These nano-complexes were in size range of 125 ± 20 nm. The complexation of IR 806 dye with chitosan improved photostability, photothermal transduction, and showed excellent biocompatibility. Cancer cells treated with CIR-PEx NPs enhanced intracellular uptake within 5 h of incubation and also displayed mitochondrial localization. With the combination of CIR-PEx NPs and a chemotherapeutic agent (i.e., mitoxantrone, MTX), a significant decline in cancer cell viability was observed in both 2D and 3D cell culture models. The chemo-photothermal effect of CIR-PEx NPs + MTX augmented apoptosis in cancer cells when irradiated with NIR light. Furthermore, when tested in the 4 T1-tumor model, the chemo-photothermal therapy showed a drastic decline in tumor volume and inhibited metastatic lung nodules. The localized hyperthermia caused by photothermal therapy reduced the primary tumor burden, and the chemotherapeutic activity of mitoxantrone further complemented by inhibiting the spread of cancer cells. The proposed chemo-photothermal therapy combination could be a promising strategy for treating triple-negative metastatic breast cancer.Corydalis yanhusuo W. T. Wang, a traditional Chinese herbal medicine, has been used as an analgesic for thousands of years and it also promotes blood circulation. In this study, 33 Corydalis yanhusuo alkaloid active components were acquired from Traditional Chinese Medicine Database and Analysis Platform (TCMSP). A total of 543 pain-related targets, 1774 arrhythmia targets, and 642 potential targets of these active components were obtained using Swiss Target Prediction, GeneCards, Open Target Platform, and Therapeutic Target Database. Fifty intersecting targets were visualized through a Venn diagram, KEGG and GO pathway enrichment analysis. The analysis proposed that sodium ion channels are likely potential targets of Corydalis yanhusuo active components as analgesia and anti-arrhythmia agents. Molecular docking showed that the 33 components could bind to Nav1.7 and Nav1.5 (two subtypes of ion channel proteins) with different binding energies. In a patch clamp study, dihydrosanguinarine and dihydrochelerythrine, two monomers with the strongest binding effects, could inhibit the peak currents and promote both activation and inactivation phases of Nav1.5. Meanwhile, dihydrosanguinarine and dihydrochelerythrine could also inhibit peak currents and promote the activation phase of Nav1.7. Therefore, the findings from this study provide valuable information for future uses of traditional Chinese medicines to treat pain and cardiovascular disease.Chemical modification of polysaccharides is important for expanding their applications and gaining new insights into their structure-property relationships. Here we reported the synthesis, characterization, and anti-viral activities of laminarin acetyl derivatives. The chemical structure and chain conformation of acetylated laminarin were characterized by FT-IR, H1 NMR, AFM, UV-vis spectrum, and induced circular dichroism based on a modified Congo Red assay (ICD-CR assay). The inhibition effect of laminarin and its acetyl derivatives on HSV-1 was evaluated by viral plaque assay and virus-associated DNA/protein change. Acetylation modification was found to trigger the conformation transition of laminarin from triple helix to single helix, and the extent of transition can be tuned by the degree of substitution. find more The single helical acetylated laminarins were found to be stable in neutral aqueous solution and exhibited no cytotoxicity. However, the acetylated laminarin exhibited declined antiviral activity after modification.Biodegradable composites were prepared from polylactic acid (PLA) and bamboo charcoal (BC) by melt blending and hot pressing. The effects of BC addition on the mechanical properties, water absorption, DMA, TGA, DSC, and CONE of BC/PLA composites were investigated. The microscopic morphology of the composites was analyzed by SEM. The results showed that for BC addition of 40 wt%, the mechanical strength, thermal properties, and flame retardant properties of the composites were improved compared with those of PLA, with a 2.24 % increase in flexural strength and a 1535 % increase (500 °C) in TG mass retention rate. The crystallinity increased by 129.66 %, the peak loss factor decreased by 31.15 %, the time required for combustion was delayed by 168 s, the peak heat release rate decreased by 29.40 %, the carbon residue rate detected by cone calorimetry increased by 48.50 %, and the peak mass loss rate decreased by 48.82 %. The addition of BC enhanced the crystallization capacity of PLA, and improved the thermal properties and flame retardant properties of the prepared composites. The results showed that materials prepared with a BC content of 40 wt% exhibited the best overall performance.Flexible films were prepared from silk fibroin (SF) and gelatin (GA) with a presence of glycerol (Gly), followed by water vapor annealing to achieve water-insoluble matrices. The blended SF/GA/Gly films were chemically conjugated with tobacco mosaic virus (TMV), either native (TMV-wt) or genetically modified with Arg-Gly-Asp (RGD) sequences (TMV-rgd), to improve cellular responses. The attachment and proliferation of L929 cells on TMV-decorated films were improved, possibly due to enhanced surface roughness. The cellular responses were pronounced with TMV-rgd, due to the proper decoration of RGD, which is an integrin recognition motif supporting cell binding. However, the biological results were inconclusive for human primary cells because of an innate slow growth kinetic of the cells. Additionally, the cells on SF/GA/Gly films were greater populated in S and G2/M phase, and the cell cycle arrest was notably increased in the TMV-conjugated group. Our findings revealed that the films modified with TMV were cytocompatible and the cellular responses were significantly enhanced when conjugated with its RGD mutants. The biological analysis on the cellular mechanisms in response to TMV is further required to ensure the safety concern of the biomaterials toward clinical translation.C2H2 zinc finger proteins (ZFPs) are a class of important transcriptional regulators in eukaryotes involved in multiple biological regulation processes. Here, MaNCP1, a C2H2 ZFP, was functionally characterized in the model entomopathogenic fungus Metarhizium acridum. Deletion of MaNCP1 delayed conidial germination and hyphal growth, decreased the conidial yield and reduced the tolerances to UV-B irradiation and heat-shock. The N-terminal zinc fingers (ZFs) of MaNCP1 made the main contributions to these traits. In addition, disruption of MaNCP1 altered the conidial surface structure and decreased the conidial hydrophobicity. Bioassays showed that the virulence of the MaNCP1-disruption strain (ΔMaNCP1) was reduced in topical inoculation compared to the WT or the mutant complemented strain (CP), and the N-terminal C2H2 ZFs made a major contribution to virulence. Furthermore, the ΔMaNCP1 and C2H2 ZFs deletion mutants (MaNCP1∆N and MaNCP1∆N+C) impaired cuticular penetration. RNA-seq showed that several cuticle-degrading genes were down-regulated in the ΔMaNCP1 background, suggesting that MaNCP1 plays vital roles in regulating insect cuticle penetration.