Adhesion Capacity Research Articles

Enhanced Intracellular Delivery and Cell Harvest Using a Candle Soot-Based Photothermal Platform with Dual-Stimulus Responsiveness.

Intracellular delivery of bioactive macromolecules and functional materials plays a crucial role in fundamental biological research and clinical applications. Nondestructive and efficient harvesting of engineered cells is also required for some specific applications. In this work, we develop a multifunctional platform based on candle soot modified with copolymer brushes containing temperature-responsive poly(N-isopropylacrylamide) (PNIPAAm) and sugar-responsive phenylboronic acid (PBA) components. This platform possesses a high cell adhesion capacity due to the inherent hierarchical structure of candle soot and the formation of boronate ester bonds between the PBA groups and glycoproteins on the cell membrane. Under the irradiation of a near-infrared laser, the excellent light-to-heat conversion ability of candle soot enables the highly efficient delivery of macromolecules into diverse cells (including hard-to-transfect cells) attached to the surface via a photothermal-poration mechanism. Owing to the temperature-responsive properties of PNIPAAm and the sugar-responsive properties of PBA, the engineered cells could be harvested nondestructively from the platform by a mild treatment using a cold fructose solution. A proof-of-concept experiment demonstrates that fibroblasts attached to the surface could be transfected by a functional plasmid encoding basic fibroblast growth factor and then harvested efficiently and recultured with improved proliferation and migration ability. The whole delivery-harvesting process required less than 1 h, allowing the cells to be engineered without compromising their viability. This platform thus provides a widely applicable method for both the intracellular delivery of diverse macromolecules efficiently as well as harvesting engineered cells simply and safely, holding great potential for biomedical applications.

Influential factors on mechanical properties and microscopic characteristics of underwater 3D printing concrete

Underwater 3D Printing Concrete (U3DPC) technology can be a promising approach to address the challenges of renewable marine energy and coastal protection. Conducting extensive research on the mechanical properties of U3DPC is crucial for its successful implementation. This study investigates various factors, including printing environment, construction methods (mold-cast and printing), curing age, and material composition, regarding their significance on the mechanical properties of U3DPC. The compressive strength, anisotropy, interlayer bonding, and interface microstructure are evaluated. The research findings reveal that compared to casting specimens in air, the printing method and water environmental factors result in approximately 20% and 15.1% reduction in the compressive strength of U3DPC, respectively. U3DPC exhibits different anisotropic variations compared to specimens printed in air, attributed to weak interlayer bonding interfaces caused by external water. The influence of material components on the interlayer bonding strength of U3DPC has a critical threshold that should not be exceeded; otherwise, it weakens the interlayer bonding. The variation in fine aggregate types and fibers leads to changes in interlayer interface roughness, where excessive roughness captures more ambient water due to the “dog-tooth overlapping” structure, thereby reducing the adhesive capacity. The pore distribution reveals the underlying mechanism of how interface roughness affects interlayer bonding.

HIF-1α increases the osteogenic capacity of ADSCs by coupling angiogenesis and osteogenesis via the HIF-1α/VEGF/AKT/mTOR signaling pathway

BackgroundStabilization and increased activity of hypoxia-inducible factor 1-α (HIF-1α) can directly increase cancellous bone formation and play an essential role in bone modeling and remodeling. However, whether an increased HIF-1α expression in adipose-derived stem cells (ADSCs) increases osteogenic capacity and promotes bone regeneration is not known.ResultsIn this study, ADSCs transfected with small interfering RNA and HIF-1α overexpression plasmid were established to investigate the proliferation, migration, adhesion, and osteogenic capacity of ADSCs and the angiogenic ability of human umbilical vein endothelial cells (HUVECs). Overexpression of HIF-1α could promote the biological functions of ADSCs, and the angiogenic ability of HUVECs. Western blotting showed that the protein levels of osteogenesis-related factors were increased when HIF-1α was overexpressed. Furthermore, the influence of upregulation of HIF-1α in ADSC sheets on osseointegration was evaluated using a Sprague–Dawley (SD) rats implant model, in which the bone mass and osteoid mineralization speed were evaluated by radiological and histological analysis. The overexpression of HIF-1α in ADSCs enhanced bone remodeling and osseointegration around titanium implants. However, transfecting the small interfering RNA (siRNA) of HIF-1α in ADSCs attenuated their osteogenic and angiogenic capacity. Finally, it was confirmed in vitro that HIF-1α promotes osteogenic differentiation and the biological functions in ADSCs via the VEGF/AKT/mTOR pathway.ConclusionsThis study demonstrates that HIF-1α has a critical ability to promote osteogenic differentiation in ADSCs by coupling osteogenesis and angiogenesis via the VEGF/AKT/mTOR signaling pathway, which in turn increases osteointegration and bone formation around titanium implants.Graphical

Bioinspired dry-state polylactic acid adhesives-based wearable sensor with reversible adhesive performance in harsh environments via building hierarchical liquid metal bead structure

Dry-state self-adhesive wearable sensors show great application in various fields. However, the poor adhesive performance, unsatisfied reversible performance, and low sensitivity in a harsh environment still limit its broad applications. Mimicking the biological design for strong adhesive has given promise for realizing reversible adhesive and high-performance sensor capacity. Drawing inspiration from the biomimetic mechanism of mussels and the mechanical interlocking adhesion mechanism, we have devised a multi-level micro/nano adhesion strategy. This innovative approach aims to create polylactic acid (PLA)-Liquid metal (LM) 3D beaded structured adhesives, with the ultimate goal of achieving significantly enhanced adhesive strength, improved water resistance, and superior mold resistance. The bioinspired PLA-based adhesives exhibit bond shear adhesion strength of 2.7625 MPa and adhesion peel strength of 290 kPa, which is higher than that of reports. Importantly, the new concept of sunlight harvesting function was introduced into the system. The adhesives show enhanced shear strength (10.77% increment) under solar irradiation due to the photothermal capacity of EGaIn. For the concept of proof, a self-adhesive LM-based wearable sensor can be assembled to detect the electrical signals triggered by strain. This work paths the way for developing multifunctional bioinspired dry-state adhesives for wearable electronics.

Programmable scaffolds with aligned porous structures for cell cultured meat

Porous scaffolds for cell cultured meat are currently limited in the food-grade material requirements, the cell adhesion, proliferation, and differentiation capacities, and the ignored appearance design. We proposed programmable scaffolds specially tailored for cell cultured meat. The scaffold with aligned porous structures was fabricated with the ice-templated directional freeze-drying of the food-grade collagen hydrogel. Due to the abundant tripeptide presence and well-aligned porous structures, the scaffold could not only provide sites for cell adhesion and proliferation, but also promote the oriented growth and differentiation of cells. The up-regulation of myogenic related genes, synthesis of myogenic related proteins and formation of matured myotubes furtherly proved the differentiation of cells on aligned scaffold. These characteristics would facilitate the traditional meat characteristics simulation of cell cultured meat in term of texture and microstructure. Meanwhile, patterned scaffolds were achievable as well with the help of mold-assisted ice templating, which would improve the people’s interest, recognition, and acceptance of the tailored cell cultured meat. These characteristics indicate great application prospects of the proposed programmable scaffolds in cell cultured meat.

Estimate of the maximum amount of dust adhering to skin and the upper limit of dust-skin adherence factor for young adults: An example from Changchun, China

Contaminants present in dust adhering to the skin can pose a significant risk to human health through dermal absorption and hand-to-mouth contact. The adhesion capacity of dust differs significantly from that of soil due to its physicochemical properties. Therefore, applying the raw soil exposure parameters to estimate the health risks associated with dermal exposure to dust may lead to erroneous conclusions. In this study, we quantified the maximum amount of dust that adhered to the skin (MADmax) and the upper limit of dust-skin adherence factor (DSAFmax) in 26 adults using element markers as a proxy for dust. The volunteers were exposed to dust and rinse water samples were collected from their hands, forearms, lower legs, and feet. We analyzed both the raw dust samples and the rinse water samples for 11 element markers, including Be, V, Cr, Mn, Co, Ni, Cu, Zn, Se, Ba, and Pb. The results showed that the MADmax of indoor dust and outdoor dust increased by 0.08–0.62 mg and 0.33–0.56 mg following a 1 cm2 increase in skin surface area, respectively. Based on best dust element markers, the body part-weighted dust-skin adherences (WDSAFmaxs) of indoor dust and outdoor dust were 0.35 and 0.64 mg/cm2, respectively. A smaller particle size and higher moisture content resulted in a larger DSAFmax. Only when indoor dust concentrations exceed 24.2 mg/m3 or outdoor dust concentrations exceed 44.3 mg/m3, can the WDSAFmax be applied directly in the health risk assessment of dermal exposure to dust. The method from this study can be re-applied in different regions, and the adherence data can help to improve future studies on the health effects of dermal exposure to dust.

Exploring the Possibility of Enriching Fermented Milks with Young Barley Leaves Powder Preparation

Barley (Hordeum vulgare L.) is one of the first cereals that humans began to cultivate. This study aimed to investigate the possibility of enriching fermented dairy products, using fermented milk as an example, with young barley leaves powder (YBLP) preparation including different starter cultures of lactic acid bacteria (LAB). The addition of YBLP did not affect the maximum rate of acidification and the time at which the maximum acidification rate was achieved. However, it did impact the time required to reach the desired pH level (4.6) for specific starter cultures. Over a 28-day storage period, gradual acidification of the fermented milk was observed. The addition of YBLP has a limited effect on the pH of the fermented milk, with the pH value primarily dependent on the type of starter culture and storage time. The addition of YBLP may have a positive effect on the survival of bacterial cells during the storage of the fermented milk; however, a gradual decrease in the number of LAB cells was observed during refrigerated storage. Furthermore, the addition of YBLP had a significant effect on the hardness, adhesion, and water-holding capacity of some fermented milk immediately after fermentation, depending on the specific starter culture used.

In situ generation of bioadhesives using dry tannic silk particles: a wet-adhesion strategy relying on removal of hydraulic layer over wet tissues for wound care

Tissue adhesives have been widely used in biomedical applications. However, the presence of a hydrated layer on the surface of wet tissue severely hinders their adhesion capacities, resulting in ineffective wound treatment. To address this issue, a dry particle dressing (plas@SF/tann-hydro-pwd) capable of removing the hydrated layer and converting in situ to bioadhesives (plas@SF/tann-hydro-gel) was fabricated via simple physical mixing based on the hydrophobic-hydrogen bonding synergistic effect and Schiff-base reaction. It was found that the plas@SF/tann-hydro-gel bioadhesive, which was changed from plas@SF/tann-hydro-pwd dressing by adsorption of water, exhibited good wet adhesion to diverse biological tissues. In addition, the wet adhesion qualities of the plas@SF/tann-hydro-gel adhesive was studied under a variety of demanding conditions, including a wide range of temperatures, varying pH levels, highly concentrated salt solutions, and simulated fluids. Experiments on animals had showed that the adhesive plas@SF/tann-hydro-gel has superior wet adhesion qualities and superior wound healing properties compared to the commercial product Tegaderm™. This study develops a new wet-adhesion technique employing dry particle dressing to eliminate the hydrated layer over wet tissues for the in situ creation of gel bioadhesives for wound healing.

Anti-inflammatory potential of lactic acid bacteria from southern Brazil by reducing TNF-α and increasing IL-10 synthesis: an in vitro study.

To evaluate the adhesion capacity and anti-inflammatory activity of lactic acid bacteria (LAB) isolated from raw cow milk and artisan cheese in Southern Brazil, investigating their effect on the release of cytokines such as TNF-α and IL-10 and their influence on the activation of the p38/MAPK pathway. Lentilactobacillus parabuchneri ML4, Lacticaseibacillus paracasei ML33, Lactiplantibacillus pentosus ML82, Lactiplantibacillus plantarum CH131, and L. paracasei CH135 demonstrated high adhesion potential in an in vitro model of the intestinal epithelium, as well as anti-inflammatory activity. After a 4-hour treatment, the strains significantly increased TNF-α levels, while a 24-hour treatment led to a significant decrease in TNF-α release. Moreover, IL-10 levels significantly increased after 24-hour and 48-hour treatments with LAB. The inhibition of p38/MAPK phosphorylation was identified as one of the mechanisms by which the L. paracasei ML33 and L. plantarum CH131 strains suppressed the production and release of TNF-α. We identified LAB strains with potential anti-inflammatory properties that could adhere to the intestinal mucosa and alleviate the inflammatory response by reducing the production and release of TNF-α through the inhibition of the p38/MAPK pathway, while promoting the production of IL-10.

Influence of cold-stimulated adipocyte supernatant on the expression of adhesion-related molecules in Schwann cell line

Bell's palsy is the most common form of facial nerve palsy. This study aimed to explore the pathogenesis of Bell's palsy by investigating the effect of cold-stimulated adipocyte supernatant on adhesion molecule expression in Schwann cell line. Schwann cells were cultured in regular or adipocyte-conditioned medium and analyzed using RNA sequencing. The mRNA expression of Schwann cell adhesion molecules melanoma cell adhesion molecule (MCAM), protocadherin 9 (PCDH9), and intercellular cell adhesion molecule 1 (ICAM1) was determined using real-time reverse-transcription polymerase chain reaction. Differentially expressed genes were identified, and Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses were conducted. Compared with Schwann cells in 37 °C, the expression of MCAM, PCDH9, and ICAM1 was downregulated in Schwann cells treated with cold-stimulated adipocyte supernatant compared with Schwann cells in 37 °C. Adipocytes subjected to cold exposure may weaken the adhesion capacity of Schwann cells and disrupt the local homeostasis of Schwann cell–axon interactions by affecting the expression of MCAM, PCDH9, and ICAM1, ultimately leading to the development of demyelinating lesions.

Fabrication and Validation of a 3D Portable PEGDA Microfluidic Chip for Visual Colorimetric Detection of Captured Breast Cancer Cells.

To guide therapeutic strategies and to monitor the state changes in the disease, a low-cost, portable, and easily fabricated microfluidic-chip-integrated three-dimensional (3D) microchamber was designed for capturing and analyzing breast cancer cells. Optimally, a colorimetric sensor array was integrated into a microfluidic chip to discriminate the metabolites of the cells. The ultraviolet polymerization characteristic of poly(ethylene glycol) diacrylate (PEGDA) hydrogel was utilized to rapidly fabricate a three-layer hydrogel microfluidic chip with the designed structure under noninvasive 365 nm laser irradiation. 2-Hydroxyethyl methacrylate (HEMA) was added to the prepolymer in order to increase the adhesive capacity of the microchip's surface for capturing cells. 1-Vinyl-2-pyrrolidone (NVP) was designed to improve the toughness and reduce the swelling capacity of the hydrogel composite. A non-toxic 3D hydrogel microarray chip (60 mm × 20 mm × 3 mm) with low immunogenicity and high hydrophilicity was created to simulate the real physiological microenvironment of breast tissue. The crisscross channels were designed to ensure homogeneous seeding density. This hydrogel material displayed excellent biocompatibility and tunable physical properties compared with traditional microfluidic chip materials and can be directly processed to obtain the most desirable microstructure. The feasibility of using a PEGDA hydrogel microfluidic chip for the real-time online detection of breast cancer cells' metabolism was confirmed using a specifically designed colorimetric sensor array with 16 kinds of porphyrin, porphyrin derivatives, and indicator dyes. The results of the principal component analysis (PCA), the hierarchical cluster analysis (HCA), and the linear discriminant analysis (LDA) suggest that the metabolic liquids of different breast cells can be easily distinguished with the developed PEGDA hydrogel microfluidic chip. The PEGDA hydrogel microfluidic chip has potential practicable applicability in distinguishing normal and cancerous breast cells.

The aggressiveness of succinate dehydrogenase subunit B-deficient chromaffin cells is reduced when their bioelectrical properties are restored by glibenclamide.

Pheochromocytomas/paragangliomas (PPGLs) are neuroendocrine tumours, mostly resulting from mutations in predisposing genes. Mutations of succinate dehydrogenase (SDH) subunit B (SDHB) are associated with high probability of metastatic disease. Since bioelectrical properties and signalling in cancer are an emerging field, we investigated the metabolic, functional and electrophysiological characteristics in human succinate dehydrogenase subunit B (SDHB)-deficient pheochromocytoma cells. These cells exhibited reduced SDH function with elevated succinate-to-fumarate ratio and reduced intracellular ATP levels. The analysis of membrane passive properties revealed a more hyperpolarized membrane potential and a lower cell capacitance of SDHB-deficient cells compared to the parental ones. These bioelectrical changes were associated with reduced proliferation and adhesion capacity of SDHB-deficient cells. Only in SDHB-deficient cells, we also observed an increased amplitude of potassium currents suggesting an activation of ATP-sensitive potassium channels (KATP). Indeed, exposure of the SDHB-deficient cells to glibenclamide, a specific KATP inhibitor, or to ATP caused normalization of potassium current features and altered proliferation and adhesion. In this work, we show for the first time that reduced intracellular ATP levels in SDHB-deficient chromaffin cells impaired cell bioelectrical properties, which, in turn, are associated with an increased cell aggressiveness. Moreover, we first ever demonstrated that glibenclamide not only reduced the outward potassium currents in SDHB-deficient cells but increased their growth capacity, reduced their ability to migrate and shifted their phenotype towards one more similar to that of parental one.

Monochasma savatieri Inhibits the Migration of the Breast Cancer Cell Line MDA- MB-231.

Monochasma savatieri, a hemiparasite of mosses, has been used as a traditional medicine in China. Currently, there is a worldwide interest in identifying novel sources of anti-cancer agents. This study aimed to assay the aqueous extract of M. savatieri to investigate its cytotoxicity and anti-migratory effect on breast cancer cells. MCF7 and MDA-MB-231 breast cancer cell lines were used to evaluate the cytotoxicity by crystal violet staining and cell cycle analysis by flow cytometry. MDA-MB-231 cells were used to analyze cell migration by the wound-healing and the Transwell® assays. In addition, the capacity of cell adhesion and spreading was tested. Activation of PARP-1, Erk and Akt, and the levels of snail, vimentin, and caveolin-1 were determined by Western blot. No significant effect was observed on survival or cell cycle studies with doses up to 500 µg/mL in MCF7 and MDA-MB-231 cells. Transwell and wound-healing assays showed that M. savatieri inhibited the migration of MDA-MB-231 cells. Western blot analysis showed a slight decrease in protein expression of factors related to epithelial-to-mesenchymal transition (snail and vimentin) and a strong decrease in the expression of caveolin-1 when cells were exposed to M. savatieri. In addition, phosphorylation levels of Erk and Akt were also deregulated due to M. savatieri. The findings of this study suggest that the aqueous extract of M. savatieri possesses anti-metastatic compounds that merit further investigation for treating breast cancer malignancy.

Effect of the Mechanical Properties of Soft Counter-Faces on the Adhesive Capacity of Mushroom-Shaped Biomimetic Microstructures.

The effects of mechanical properties and contact environment conditions on the adhesiveness of the biomimetic adhesive mushroom-shaped micro-structure have been experimentally investigated. The idea is based on the adhesive micro-structures and surfaces inspired by nature after observing the abilities of some animals. Applications are proposed in various fields of engineering and technology. However, to enable unconventional uses of these biomimetic adhesion surfaces, such as in the biomedical field, it is necessary to adjust and optimize their tribological properties (friction, adhesion, and peeling strength) in contact with soft substrates that can simulate the mechanical features of biological tissues. Our work explores the effect of the combinations of the various parameters on the strength of adhesion. Under dry contact conditions, soft counter-faces lead to lower adhesion than hard counter-faces, whereas under wet conditions, soft counter-faces lead to higher adhesion than harder counter-faces.

Dual localization of receptor-type adenylate cyclases and cAMP response protein 3 unveils the presence of two putative signaling microdomains in Trypanosoma cruzi.

Trypanosoma cruzi is the etiologic agent of Chagas disease, a leading cause of disability and premature death in the Americas. This parasite spends its life between a triatomine insect and a mammalian host, transitioning between developmental stages in response to microenvironmental changes. Among the second messengers driving differentiation in T. cruzi, cAMP has been shown to mediate metacyclogenesis and response to osmotic stress, but this signaling pathway remains largely unexplored in this parasite. Adenylate cyclases (ACs) catalyze the conversion of ATP to cAMP. They comprise a multigene family encoding putative receptor-type ACs in T. cruzi. Using protein sequence alignment, we classified them into five groups and chose a representative member from each group to study their localization (TcAC1-TcAC5). We expressed an HA-tagged version of each protein in T. cruzi and performed immunofluorescence analysis. A peculiar dual localization of TcAC1 and TcAC2 was observed in the flagellar distal domain and in the contractile vacuole complex (CVC), and their enzymatic activity was confirmed by gene complementation in yeast. Furthermore, TcAC1 overexpressing parasites showed an increased metacyclogenesis, a defect in host cell invasion, and a reduced intracellular replication, highlighting the importance of this protein throughout T. cruzi life cycle. These mutants were more tolerant to hypoosmotic stress and showed a higher adhesion capacity during in vitro metacyclogenesis, whereas the wild-type phenotype was restored after disrupting TcAC1 localization. Finally, TcAC1 was found to interact with cAMP response protein 3 (TcCARP3), co-localizing with this protein in the flagellar tip and CVC. IMPORTANCE We identified three components of the cAMP signaling pathway (TcAC1, TcAC2, and TcCARP3) with dual localization in Trypanosoma cruzi: the flagellar distal domain and the CVC, structures involved in cell adhesion and osmoregulation, respectively. We found evidence on the role of TcAC1 in both cellular processes, as well as in metacyclogenesis. Our data suggest that TcACs act as signal sensors and transducers through cAMP synthesis in membrane microdomains. We propose a model in which TcACs sense the harsh conditions in the triatomine hindgut (nutrient deprivation, acidic pH, osmotic stress, ionic composition, hydrophobic interactions) and become active. Synthesis of cAMP then triggers cell adhesion prior completion of metacyclogenesis, while mediating a response to osmotic stress in the parasite. These results shed light into the mechanisms driving cAMP-mediated cell differentiation in T. cruzi, while raising new questions on the activation of TcACs and the role of downstream components of this pathway.

Structural analysis and adhesive capacity of cassava starch modified with NaOH:urea mixtures

In this research the interactions and structural changes induced by NaOH:urea mixtures on cassava starch suspensions as well as their adhesive capacity were studied. Cold gelatinization of 10–20% w/w cassava suspensions was induced by adding different NaOH:urea mixtures (0.5–2:1). Chemical modification of cassava starch was analyzed through optical microscopy as well as SEC-HPLC and size particle determinations, ATR-FTIR spectral and chemometric analysis were also carried out.Cassava starch treatment with NaOH:urea mixtures generated structural disorganization, induced cold gelatinization and promoted the hydrolysis of the polymeric chains. SEC-HPLC and ATR-FTIR results showed that the modifications induced in the adhesive formulations depend both on the starch content and the NaOH:urea ratio. All tested formulations exhibited adhesive capacity, being effective for Kraft paper substrate bonding. Thus, this simple and low-cost procedure was effective to chemically modify cassava starch allowing to obtain derivatives with tailor-made adhesive properties.

Fabrication of cell cultured meat by hydrogel with topographic microstructures

Cell cultured meat (CCM) is an innovative food in cellular agriculture derived from culturing cells in vitro rather than slaughtering livestock. Currently, the fabrications of hydrogel for CCM applications are limited in the food-grade material, cell adhesion, proliferation, and differentiation capacities. Thus, an edible collagen hydrogel with linearly aligned microgrooves was fabricated to direct muscle stem cells (MSCs) alignment. In proliferation, more than 65% MSCs were parallel to the topographic microstructures of the hydrogel. Furtherly, the results demonstrated that by benefiting from the well-aligned microgrooves and sufficient cell cultivation, MSCs could differentiate into longer myotubes, with higher expression of related differentiation genes (myosin heavy chain, MyHC-2a and MyHC-slow) and protein (MyHC) than flat hydrogel surface on day 9. Moreover, the types and content of amino acids in natural pork and CCM were also assessed. The amino acids types were consistent while the amino acid content of pork (21.89%) were significantly higher than CCM (11.24%), the gap affirming that some quality characteristics can be facilitated to imitate traditional meat by designing hydrogels in future production. These findings indicate excellent application prospects of the hydrogel with topographic microstructures in CCM.

Multilayer Coating with Red Ginseng Dietary Fiber Improves Intestinal Adhesion and Proliferation of Probiotics in Human Intestinal Epithelial Models.

To exert their beneficial effects, it is essential for the commensal bacteria of probiotic supplements to be sufficiently protected as they pass through the low pH environment of the stomach, and effectively colonize the intestinal epithelium downstream. Here, we investigated the effect of a multilayer coating containing red ginseng dietary fiber, on the acid tolerance, and the adhesion and proliferation capacities of three Lactobacillus strains (Limosilactobacillus reuteri KGC1901, Lacticaseibacillus casei KGC1201, Limosilactobacillus fermentum KGC1601) isolated from Panax ginseng, using HT-29 cells, mucin-coated plates, and human pluripotent stem cell-derived intestinal epithelial cells as in vitro models of human gut physiology. We observed that the multilayer-coated strains displayed improved survival rates after passage through gastric juice, as well as high adhesion and proliferation capacities within the various gut epithelial systems tested, compared to their uncoated counterparts. Our findings demonstrated that the multilayer coat effectively protected commensal microbiota and led to improved adhesion and colonization of intestinal epithelial cells, and consequently to higher probiotic efficacy.

Robust and smart underwater adhesion of hydrophobic hydrogel by phase change

Water-durable adhesives are widely explored in various fields like wearable electronics, tissue engineering and sea refloatation. However, in harsh underwater environment, adhesives with sound and comprehensive performance on various surfaces remain highly challenging. Herein, we report a hydrophobic hydrogel adhesive composed of crystalline octadecyl (C18) chains with versatile, robust and thermally switchable underwater adhesion. The inherent hydrophobicity and the amorphous state of C18 chains allow the hydrogel adhesive to conformally adapt to underwater surfaces, independent of surface energy, curvature, charge and roughness as well as the salinity and pH of the water environment. The crystallization of C18 chains greatly increases the modulus of the hydrogel, interlocking the adhesive to the contacting surfaces and resulting in the underwater adhesion up to 275 kPa. The phase change of hydrogel regulates the stress distribution at the contact interface and the adhesion capacity, resulting in a switchable underwater adhesion. The phase change of C18 chains also endows the hydrogel self-healing property, ensuring durability and reusability. Moreover, the temperature of phase change is around ∼ 40 ℃, endowing adhesive with bio-applications in dynamic watery environments. Therefore, the adhesive is highly potential in emerging areas of wearable electronics, tissue engineering and so on.

Low-Density Lipoprotein Receptor Is a Key Driver of Aggressiveness in Thyroid Tumor Cells.

We previously described the role of low-density lipoprotein (LDL) in aggressiveness in papillary thyroid cancer (PTC). Moreover, the MAPK signaling pathway in the presence of BRAF V600E mutation is associated with more aggressive PTC. Although the link between MAPK cascade and LDL receptor (LDLR) expression has been previously described, it is unknown whether LDL can potentiate the adverse effects of PTC through it. We aimed to investigate whether the presence of LDL might accelerate the oncogenic processes through MAPK pathway in presence or absence of BRAF V600E in two thyroid cell lines: TPC1 and BCPAP (wild-type and BRAF V600E, respectively). LDLR, PI3K-AKT and RAS/RAF/MAPK (MEK)/ERK were analyzed via Western blot; cell proliferation was measured via MTT assay, cell migration was studied through wound-healing assay and LDL uptake was analyzed by fluorometric and confocal analysis. TPC1 demonstrated a time-specific downregulation of the LDLR, while BCPAP resulted in a receptor deregulation after LDL exposition. LDL uptake was increased in BCPAP over-time, as well as cell proliferation (20% higher) in comparison to TPC1. Both cell lines differed in migration pattern with a wound closure of 83.5 ± 9.7% after LDL coculture in TPC1, while a loss in the adhesion capacity was detected in BCPAP. The siRNA knockdown of LDLR in LDL-treated BCPAP cells resulted in a p-ERK expression downregulation and cell proliferation modulation, demonstrating a link between LDLR and MAPK pathway. The modulation of BRAF-V600E using vemurafenib-impaired LDLR expression decreased cellular proliferation. Our results suggest that LDLR regulation is cell line-specific, regulating the RAS/RAF/MAPK (MEK)/ERK pathway in the LDL-signaling cascade and where BRAF V600E can play a critical role. In conclusion, targeting LDLR and this downstream signaling cascade, could be a new therapeutic strategy for PTC with more aggressive behavior, especially in those harboring BRAF V600E.