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Journal of Functional Biomaterials Jun 2024With the rising demand for medical implants and the dominance of implant-associated failures including infections, extensive research has been prompted into the...
With the rising demand for medical implants and the dominance of implant-associated failures including infections, extensive research has been prompted into the development of novel biomaterials that can offer desirable characteristics. This study develops and evaluates new titanium-based alloys containing gallium additions with the aim of offering beneficial antibacterial properties while having a reduced stiffness level to minimise the effect of stress shielding when in contact with bone. The focus is on the microstructure, mechanical properties, antimicrobial activity, and cytocompatibility to inform the suitability of the designed alloys as biometals. Novel Ti-33Nb-xGa alloys (x = 3, 5 wt%) were produced via casting followed by homogenisation treatment, where all results were compared to the currently employed alloy Ti-6Al-4V. Optical microscopy, scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS) results depicted a single beta (β) phase microstructure in both Ga-containing alloys, where Ti-33Nb-5Ga was also dominated by dendritic alpha (α) phase grains in a β-phase matrix. EDS analysis indicated that the α-phase dendrites in Ti-33Nb-5Ga were enriched with titanium, while the β-phase was richer in niobium and gallium elements. Mechanical properties were measured using nanoindentation and microhardness methods, where the Young's modulus for Ti-33Nb-3Ga and Ti-33Nb-5Ga was found to be 75.4 ± 2.4 and 67.2 ± 1.6 GPa, respectively, a significant reduction of 37% and 44% with respect to Ti-6Al-4V. This reduction helps address the disproportionate Young's modulus between titanium implant components and cortical bone. Importantly, both alloys successfully achieved superior antimicrobial properties against Gram-negative and Gram-positive bacteria. Antibacterial efficacy was noted at up to 90 ± 5% for the 3 wt% alloy and 95 ± 3% for the 5 wt% alloy. These findings signify a substantial enhancement of the antimicrobial performance when compared to Ti-6Al-4V which exhibited very small rates (up to 6.3 ± 1.5%). No cytotoxicity was observed in hGF cell lines over 24 h. Cell morphology and cytoskeleton distribution appeared to depict typical morphology with a prominent nucleus, elongated fibroblastic spindle-shaped morphology, and F-actin filamentous stress fibres in a well-defined structure of parallel bundles along the cellular axis. The developed alloys in this work have shown very promising results and are suggested to be further examined towards the use of orthopaedic implant components.
PubMed: 38921540
DOI: 10.3390/jfb15060167 -
Biomimetics (Basel, Switzerland) Jun 2024The blood coagulation test is an indispensable test for monitoring the blood coagulation and fibrinolysis functions. Currently, activated partial thromboplastin time...
The blood coagulation test is an indispensable test for monitoring the blood coagulation and fibrinolysis functions. Currently, activated partial thromboplastin time (APTT) is the most widely used approach to coagulation testing. However, APTT reagents need to be optimized due to the fact that they are unstable, highly variable, and cannot be easily controlled. In this study, we created apoptotic cell-inspired methacryloyloxyethyl phosphorylserine (MPS) particles for blood coagulation as an alternative to conventional APTT reagents. Particle size could be controlled by changing the concentration of the polymer. The blood coagulation ability of particles was stable at different environmental temperatures. Moreover, the procoagulant activity could be enhanced by increasing the concentration to 0.06 mg/mL and reducing the size of the particles to around 900 nm. Fibrin clotted by particles showed no significant difference from that formed by APTT regent Actin FSL. We propose that MPS particles are a potential alternative to Actin FS for the application of blood coagulation tests.
PubMed: 38921247
DOI: 10.3390/biomimetics9060367 -
Biomimetics (Basel, Switzerland) May 2024In this study, we report on the development of hydroxyapatite (HAp) and samarium-doped hydroxyapatite (SmHAp) nanoparticles using a cost-effective method and their...
In this study, we report on the development of hydroxyapatite (HAp) and samarium-doped hydroxyapatite (SmHAp) nanoparticles using a cost-effective method and their biological effects on a bone-derived cell line MC3T3-E1. The physicochemical and biological features of HAp and SmHAp nanoparticles are explored. The X-ray diffraction (XRD) studies revealed that no additional peaks were observed after the integration of samarium (Sm) ions into the HAp structure. Valuable information regarding the molecular structure and morphological features of nanoparticles were obtained by using Fourier-transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS). The elemental composition obtained by using energy-dispersive X-ray spectroscopy (EDS) confirmed the presence of the HAp constituent elements, Ca, O, and P, as well as the presence and uniform distribution of Sm ions. Both HAp and SmHAp nanoparticles demonstrated biocompatibility at concentrations below 25 μg/mL and 50 μg/mL, respectively, for up to 72 h of exposure. Cell membrane integrity was preserved following treatment with concentrations up to 100 μg/mL HAp and 400 μg/mL SmHAp, confirming the role of Sm ions in enhancing the cytocompatibility of HAp. Furthermore, our findings reveal a positive, albeit limited, effect of SmHAp nanoparticles on the actin dynamics, osteogenesis, and cell migration compared to HAp nanoparticles. Importantly, the biological results highlight the potential role of Sm ions in maintaining cellular balance by mitigating disruptions in Ca homeostasis induced by HAp nanoparticles. Therefore, our study represents a significant contribution to the safety assessment of both HAp and SmHAp nanoparticles for biomedical applications focused on bone regeneration.
PubMed: 38921189
DOI: 10.3390/biomimetics9060309 -
Current Issues in Molecular Biology Jun 2024is widely used as an ornamental, medicine, and perfume in industry. Real-time fluorescence quantitative polymerase chain reaction (RT-qPCR) is widely and accurately...
is widely used as an ornamental, medicine, and perfume in industry. Real-time fluorescence quantitative polymerase chain reaction (RT-qPCR) is widely and accurately utilized for gene expression evaluations. Selecting optimal reference genes is essential for normalizing RT-qPCR results. However, the identification of suitable reference genes in . has not been documented. A total of 12 reference genes in . were identified by PEG6000 (15%) treatment under hypertonia conditions in different tissues (roots, stem, leaves, flower, seeds and sepal) and during three stages of flower development, then used to validate the expression stability. There were four algorithms (delta Ct, geNorm, NormFinder, and BestKeeper) used to analyze the stability. Finally, the RefFinder program was employed to evaluate the candidate reference genes' stability. The results showed that , (), and () were stable reference genes under the PEG6000 treatment. () was the most stable gene across different flower development stages. () was the most stable gene in different tissues and total samples. This study provides reliable gene expression studies for future research in . .
PubMed: 38921046
DOI: 10.3390/cimb46060375 -
Cells Jun 2024Aberrant sialylation with overexpression of the homopolymeric glycan polysialic acid (polySia) was recently reported in fibroblasts from fibrotic skin lesions. Yet,...
Aberrant sialylation with overexpression of the homopolymeric glycan polysialic acid (polySia) was recently reported in fibroblasts from fibrotic skin lesions. Yet, whether such a rise in polySia levels or sialylation in general may be functionally implicated in profibrotic activation of fibroblasts and their transition to myofibroblasts remains unknown. Therefore, we herein explored whether inhibition of sialylation could interfere with the process of skin fibroblast-to-myofibroblast transition induced by the master profibrotic mediator transforming growth factor β1 (TGFβ1). Adult human skin fibroblasts were pretreated with the competitive pan-sialyltransferase inhibitor 3-Fax-peracetyl-Neu5Ac (3-Fax) before stimulation with recombinant human TGFβ1, and then analyzed for polySia expression, cell viability, proliferation, migratory ability, and acquisition of myofibroblast-like morphofunctional features. Skin fibroblast stimulation with TGFβ1 resulted in overexpression of polySia, which was effectively blunted by 3-Fax pre-administration. Pretreatment with 3-Fax efficiently lessened TGFβ1-induced skin fibroblast proliferation, migration, changes in cell morphology, and phenotypic and functional differentiation into myofibroblasts, as testified by a significant reduction in , , , , and gene expression, and α-smooth muscle actin, N-cadherin, COL1A1, and FN-EDA protein levels, as well as a reduced contractile capability. Moreover, skin fibroblasts pre-administered with 3-Fax displayed a significant decrease in Smad3-dependent canonical TGFβ1 signaling. Collectively, our in vitro findings demonstrate for the first time that aberrant sialylation with increased polySia levels has a functional role in skin fibroblast-to-myofibroblast transition and suggest that competitive sialyltransferase inhibition might offer new therapeutic opportunities against skin fibrosis.
Topics: Humans; Transforming Growth Factor beta1; Skin; Sialic Acids; Myofibroblasts; Fibroblasts; Cell Proliferation; Cell Differentiation; Cell Movement; Sialyltransferases; Signal Transduction; Cells, Cultured
PubMed: 38920695
DOI: 10.3390/cells13121067 -
Biosensors Jun 2024The overall 5-year survival rate of ovarian cancer (OC) is generally low as the disease is often diagnosed at an advanced stage of progression. To save lives, OC must be...
The overall 5-year survival rate of ovarian cancer (OC) is generally low as the disease is often diagnosed at an advanced stage of progression. To save lives, OC must be identified in its early stages when treatment is most effective. Early-stage OC causes the upregulation of lysophosphatidic acid (LPA), making the molecule a promising biomarker for early-stage detection. An LPA assay can additionally stage the disease since LPA levels increase with OC progression. This work presents two methods that demonstrate the prospective application for detecting LPA: the electromagnetic piezoelectric acoustic sensor (EMPAS) and a chemiluminescence-based iron oxide nanoparticle (IONP) approach. Both methods incorporate the protein complex gelsolin-actin, which enables testing for detection of the biomarker as the binding of LPA to the complex results in the separation of gelsolin from actin. The EMPAS was characterized with contact angle goniometry and atomic force microscopy, while gelsolin-actin-functionalized IONPs were characterized with transmission electron microscopy and Fourier transform infrared spectroscopy. In addition to characterization, LPA detection was demonstrated as a proof-of-concept in Milli-Q water, buffer, or human serum, highlighting various LPA assays that can be developed for the early-stage detection of OC.
Topics: Lysophospholipids; Humans; Female; Ovarian Neoplasms; Biomarkers, Tumor; Biosensing Techniques; Gelsolin; Actins; Early Detection of Cancer
PubMed: 38920591
DOI: 10.3390/bios14060287 -
Nature Cardiovascular Research Oct 2023Missense variants throughout , encoding smooth muscle α-actin (αSMA), predispose to adult-onset thoracic aortic disease, but variants disrupting arginine 179 (R179)...
Missense variants throughout , encoding smooth muscle α-actin (αSMA), predispose to adult-onset thoracic aortic disease, but variants disrupting arginine 179 (R179) lead to Smooth Muscle Dysfunction Syndrome (SMDS) characterized by diverse childhood-onset vascular diseases. Here we show that αSMA localizes to the nucleus in wildtype (WT) smooth muscle cells (SMCs), enriches in the nucleus with SMC differentiation, and associates with chromatin remodeling complexes and SMC contractile gene promotors. The p.R179 αSMA variant shows decreased nuclear localization. Primary SMCs from mice are less differentiated than WT SMCs and and have global changes in chromatin accessibility. Induced pluripotent stem cells from patients with p.R179 variants fail to fully differentiate from neuroectodermal progenitor cells to SMCs, and single-cell transcriptomic analyses of an p.R179H patient's aortic tissue show increased SMC plasticity. Thus, nuclear αSMA participates in SMC differentiation, and loss of this nuclear activity occurs with p.R179 pathogenic variants.
PubMed: 38919852
DOI: 10.1038/s44161-023-00337-4 -
Plant Disease Jun 2024Dragon fruit (Selenicereus undatus) is a valuable fruit crop in tropical and subtropical regions. It is renowned for its nutritional benefits, such as high sodium,...
Dragon fruit (Selenicereus undatus) is a valuable fruit crop in tropical and subtropical regions. It is renowned for its nutritional benefits, such as high sodium, potassium, and vitamin levels, and as a source of prebiotics and antioxidants (Balendres et al. 2019). In July 2023, anthracnose symptoms on stems were detected on dragon fruit plants in Jeju, South Korea. The typical anthracnose symptoms, such as sunken necrotic lesions (5-20 mm in diameter), were seen on the mature stems. The disease incidence ranged from 10% to 12% among the three surveyed greenhouses. To isolate the causative organism, infected stem samples were surface sterilized, cut into small pieces, and placed on potato dextrose agar (PDA). After two days of incubation at 24ºC, white hyphae appeared on the PDA around the plant tissues. Isolates CNU H23009 and CNU H23010 were purified from a single hypha under a stereoscope (e-Xtra Figure 1). Conidial morphology was examined from two-day-old fungal cultures grown on V8 juice agar. The conidia were transparent, aseptate, cylindrical to clavate, with a rounded apex and base, and measured 11.9 - 16.85 × 5.17 - 6.91 μm (mean = 15.28 × 5.93 μm, n = 30). No appressoria was observed. Morphological characteristics indicated the isolates were Colletotrichum sp. matching the description of the C. gloeosporioides species complex (Weir et al. 2012). To further identify the isolates, genomic DNA was extracted and the ribosomal internal transcribed spacer (ITS) region, glyceraldehyde-3-phosphate dehydrogenase (GAPDH), and actin (ACT) were amplified using ITS1/ITS4, GDF/GDR, and ACT-512F/ACT-783R, respectively (Weir et al. 2012). Based on phylogenetic analysis, the isolates clustered with C. aenigma (strains ICMP18608, ICMP18686, CSH2, and QSG1), with 71% bootstrap support, as determined using the maximum parsimony method in PAUP 4.0 (e-Xtra Figure 2). Based on morphological and molecular characteristics, isolates were identified as C. aenigma. Sequences of CNU H23009 and CNU H23010 were deposited in GenBank with accession numbers OR535144 and OR535145 for ITS, OR540725 and OR540726 for GAPDH, and OR540723 and OR540724 for ACT. The pathogenicity was tested on healthy dragon fruit stems using wound inoculation with mycelial plugs of the CNU H23009 isolate. Controls were inoculated with PDA plugs. The plants were covered with plastic bags to maintain humidity and incubated in a greenhouse at 25ºC. After two days, necrotic spots had developed on the inoculated tissues; after four days, black, irregular, and sunken necrotic lesions similar to those seen in the field were observed. No symptoms occurred in the controls. C. aenigma was re-isolated from the artificially inoculated plants and re-identified based on conidial morphology. The pathogenicity test was repeated three times with three replications for each treatment. Previous studies have reported that C. aenigma, C. gloeosoporioides, C. siamense, C. truncatum, and C. karsti cause anthracnose in dragon fruit. However, C. aenigma has been reported only in Thailand (Balendres et al. 2019; Meetum et al. 2015). To our knowledge, this is the first report of C. aenigma causing anthracnose in dragon fruit in Korea.
PubMed: 38916904
DOI: 10.1094/PDIS-09-23-1894-PDN -
Ibrain 2024Neurodegenerative diseases represent an increasingly burdensome challenge of the past decade, primarily driven by the global aging of the population. Ongoing efforts...
Neurodegenerative diseases represent an increasingly burdensome challenge of the past decade, primarily driven by the global aging of the population. Ongoing efforts focus on implementing diverse strategies to mitigate the adverse effects of neurodegeneration, with the goal of decelerating the pathology progression. Notably, in recent years, it has emerged that the use of nanoparticles (NPs), particularly those obtained through green chemical processes, could constitute a promising therapeutic approach. Green NPs, exclusively sourced from phytochemicals, are deemed safer compared to NPs synthetized through conventional chemical route. In this study, the effects of green chemistry-derived silver NPs (AgNPs) were assessed in neuroblastoma cells, SHSY-5Y, which are considered a pivotal model for investigating neurodegenerative diseases. Specifically, we used two different concentrations (0.5 and 1 µM) of AgNPs and two time points (24 and 48 h) to evaluate the impact on neuroblastoma cells by observing viability reduction and intracellular calcium production, especially using 1 µM at 48 h. Furthermore, investigation using atomic force microscopy (AFM) unveiled an alteration in Young's modulus due to the reorganization of cortical actin following exposure to green AgNPs. This evidence was further corroborated by confocal microscopy acquisitions as well as coherency and density analyses on actin fibers. Our in vitro findings suggest the potential efficacy of green AgNPs against neurodegeneration; therefore, further in vivo studies are imperative to optimize possible therapeutic protocols.
PubMed: 38915951
DOI: 10.1002/ibra.12157 -
BioRxiv : the Preprint Server For... Jun 2024The keratin cytoskeleton and associated desmosomes contribute to the mechanical stability of epithelial tissues, but their organization in bladder umbrella cells and...
The keratin cytoskeleton and associated desmosomes contribute to the mechanical stability of epithelial tissues, but their organization in bladder umbrella cells and their responses to bladder filling are poorly understood. Using super-resolution confocal microscopy, along with 3D image reconstruction and platinum replica electron microscopy, we observed that the apical keratin network of umbrella cells was organized as a dense tile-like mesh comprised of tesserae bordered on their edges by cortical actin filaments, filled with woven keratin filaments, and crosslinked by plectin. A band of keratin was also observed at the cell periphery that was linked to the junction-associated actin ring by plectin. During bladder filling, the junction-localized desmosomal necklace expanded, and a subjacent girded layer was formed that linked the keratin network to desmosomes, including those at the umbrella cell-intermediate cell interface. Disruption of plectin led to focal keratin network dissolution, loss of the junction-associated band of keratin, perturbation of tight junction continuity, and loss of cell-cell cohesion. Our studies reveal a novel tile-like organization of the umbrella cell keratin cytoskeleton that is dependent on plectin, that reorganizes in response to bladder filling, and that likely serves to maintain umbrella cell continuity in the face of mechanical distension.
PubMed: 38915686
DOI: 10.1101/2024.06.11.598498