Structurally and mechanically tuned macroporous hydrogels for scalable mesenchymal stem cell-extracellular matrix spheroid production.

Mesenchymal stem cells (MSCs) are essential in regenerative medicine. However, conventional expansion and harvesting methods often fail to maintain the essential extracellular matrix (ECM) components, which are crucial for their functionality and efficacy in therapeutic applications. Here, we introduce a bone marrow-inspired macroporous hydrogel designed for the large-scale production of MSC-ECM spheroids. Through a soft-templating approach leveraging liquid-liquid phase separation, we engineer macroporous hydrogels with customizable features, including pore size, stiffness, bioactive ligand distribution, and enzyme-responsive degradability. These tailored environments are conducive to optimal MSC proliferation and ease of harvesting. We find that soft hydrogels enhance mechanotransduction in MSCs, establishing a standard for hydrogel-based 3D cell culture. Within these hydrogels, MSCs exist as both cohesive spheroids, preserving their innate vitality, and as migrating entities that actively secrete functional ECM proteins. Additionally, we also introduce a gentle, enzymatic harvesting method that breaks down the hydrogels, allowing MSCs and secreted ECM to naturally form MSC-ECM spheroids. These spheroids display heightened stemness and differentiation capacity, mirroring the benefits of a native ECM milieu. Our research underscores the significance of sophisticated materials design in nurturing distinct MSC subpopulations, facilitating the generation of MSC-ECM spheroids with enhanced therapeutic potential.

Blocking Nonspecific Interactions Using Y-Shape Poly(ethylene glycol).

Nonspecific interactions play a significant role in physiological activities, surface chemical modification, and artificial adhesives. However, nonspecificity sometimes causes sticky problems, including surface fouling, decreased target specificity, and artifacts in single-molecule measurements. Adjusting the liquid pH, using protein-blocking additives, adding nonionic surfactants, or increasing the salt concentration are common methods to minimize nonspecific binding to achieve high-quality data. Here, we report that grafting heteromorphic polyethylene glycol (Y-shape PEG) with two inert terminates could noticeably decrease nonspecific binding. As a proof-of-concept, we performed single-molecule force spectroscopy and fluorescence staining imaging experiments to verify the feasibility of Y-shape PEG in blocking nonspecific interactions. Our results indicate that Y-shape PEG could serve as a prominent and efficient candidate to minimize nonspecificity for scientific and biomedical applications.

Circulating microRNA-30a-5p, microRNA-101-3p, microRNA-140-3p and microRNA-141-3p as potential biomarkers for dexmedetomidine response in pediatric patients.

PURPOSE: The aim of this study was to investigate the expression levels of plasma miR-30a-5p, miR-101-3p, miR-140-3p and miR-141-3p and their relationship to dexmedetomidine efficacy and adverse effects in pediatric patients. METHODS: The expression levels of miR-30a-5p, miR-101-3p, miR-140-3p and miR-141-3p were measured by qRT-PCR in plasma of 133 pediatric patients receiving dexmedetomidine for preoperative sedation. We analyzed the relationship between miRNA abundance and dexmedetomidine response, including sedative effect and adverse effects, and assessed the predictive power of miRNAs for drug response. RESULTS: Among 133 pediatric patients, 111 patients were dexmedetomidine responders (UMSS ≥ 2) and 22 patients were non-responders (UMSS < 2). We observed higher expression levels of miR-101-3p and miR-140-3p in dexmedetomidine responders compared with non-responders (P < 0.05, P < 0.0001). In contrast, there was no significant difference in the expression levels of miR-30a-5p and miR-141-3p between responders and non-responders (P > 0.05). The plasma levels of miR-101-3p and miR-30a-5p were markedly downregulated in patients who experienced hypotension and bradycardia, respectively (P < 0.05). MiR-101-3p and miR-140-3p demonstrated a potential discriminatory ability between dexmedetomidine responders and non-responders, with AUC of 0.64 (P < 0.05) and 0.77 (P < 0.0001), respectively. The AUC of miR-101-3p in distinguishing patients without hypotension was 0.63 (P < 0.05). The AUC of miR-30a-5p in distinguishing patients without bradycardia was 0.74 (P < 0.05). CONCLUSION: Our study demonstrated that circulating miR-101-3p, miR-140-3p and miR-30a-5p might be used as a blood-based marker for dexmedetomidine efficacy and safety in pediatric patients.

Toward Practical Applications of Engineered Living Materials with Advanced Fabrication Techniques.

Engineered Living Materials (ELMs) are materials composed of or incorporating living cells as essential functional units. These materials can be created using bottom-up approaches, where engineered cells spontaneously form well-defined aggregates. Alternatively, top-down methods employ advanced materials science techniques to integrate cells with various kinds of materials, creating hybrids where cells and materials are intricately combined. ELMs blend synthetic biology with materials science, allowing for dynamic responses to environmental stimuli such as stress, pH, humidity, temperature, and light. These materials exhibit unique "living" properties, including self-healing, self-replication, and environmental adaptability, making them highly suitable for a wide range of applications in medicine, environmental conservation, and manufacturing. Their inherent biocompatibility and ability to undergo genetic modifications allow for customized functionalities and prolonged sustainability. This review highlights the transformative impact of ELMs over recent decades, particularly in healthcare and environmental protection. We discuss current preparation methods, including the use of endogenous and exogenous scaffolds, living assembly, 3D bioprinting, and electrospinning. Emphasis is placed on ongoing research and technological advancements necessary to enhance the safety, functionality, and practical applicability of ELMs in real-world contexts.

HK1 from hepatic stellate cell-derived extracellular vesicles promotes progression of hepatocellular carcinoma.

Extracellular vesicles play crucial roles in intercellular communication in the tumor microenvironment. Here we demonstrate that in hepatic fibrosis, TGF-ß stimulates the palmitoylation of hexokinase 1 (HK1) in hepatic stellate cells (HSCs), which facilitates the secretion of HK1 via large extracellular vesicles in a TSG101-dependent manner. The large extracellular vesicle HK1 is hijacked by hepatocellular carcinoma (HCC) cells, leading to accelerated glycolysis and HCC progression. In HSCs, the nuclear receptor Nur77 transcriptionally activates the expression of depalmitoylase ABHD17B to inhibit HK1 palmitoylation, consequently attenuating HK1 release. However, TGF-ß-activated Akt functionally represses Nur77 by inducing Nur77 phosphorylation and degradation. We identify the small molecule PDNPA that binds Nur77 to generate steric hindrance to block Akt targeting, thereby disrupting Akt-mediated Nur77 degradation and preserving Nur77 inhibition of HK1 release. Together, this study demonstrates an overlooked function of HK1 in HCC upon its release from HSCs and highlights PDNPA as a candidate compound for inhibiting HCC progression.

Highly sensitive and selective aflatoxin B1 biosensor based on Exonuclease I-catalyzed target recycling amplification and targeted response aptamer-crosslinked hydrogel using electronic balances as a readout.

The biosensors based on aptamer based stimuli-responsive hydrogels have the characters of high specificity, good stability, portability. Electronic balance is one of the most accurate equipment and can be reached nearly in all labs. Aflatoxin B1 (AFB1) is highly toxic and carcinogenic to humans and animals, it is necessary to develop simple and convenient detection method to apply in resource limited area. In this study, a novel strategy for quantitative detection of AFB1 has been developed by combining the high selectivity and convenient of target-responsive hydrogel and the simple of using electronic balance as readout devices. The AFB1 target responsive double crosslinked hydrogel has been constructed using linear hyaluronic acid grafted single-stranded DNA complex as the backbone, AFB1 aptamer and polyethyleneimine as crosslinkers. And platinum nanoparticles (PtNPs) had been embedded in the hydrogel firstly. The present of AFB1 can bind with the aptamer with high affinity and cause the releasing of aptamer from hydrogel. The addition of Exo I can specifically recognize and cleave the aptamer in AFB1-aptamer complex, resulting in the releasing of AFB1, which can react with the hydrogel again, thereby achieving the target cycle. By this means, the hydrogel will collapse and many pre-embedded PtNPs can be released. The transferring of the released PtNPs to a drainage device which contains H2O2 can results in the increasing of the internal pressure since the production of oxygen through the catalytic decomposition of H2O2 by PtNPs has low solubility. Which will cause the discharging of water from the system and this can be collected and weighed by an electronic balance easily. The weight of water has a linear relationship with AFB1 concentration. Under 30 min catalytic time, the linear range is 31.2 µg/kg - 6.2 mg/kg with the detection limit of 9.4 µg/kg (S/N = 3). The proposed method was successfully applied to the detection of AFB1 in peanut samples.

Ultrasensitive and Portable Assay for Lead(II) Ions by Electronic Balance as a Readout.

Lead ions (Pb2+) cause harm to human health. Therefore, the development of fast, effective, and convenient sensors for Pb2+ monitoring has received great attention. In this study, a portable method has been proposed for Pb2+ detection using normal electronic balance as a readout. Magnetic bead-catalytic strand is hybridized with platinum nanoparticles (Pt NPs) functioned substrate strand (Pt-Sub) to form double-stranded DNA first. In the presence of Pb2+, the DNAzyme is activated and cleaved at the ribo-adenosine site of the substrate strand and hence causes Pt NPs to be released into the supernatant, which can be easily separated from the Pt-Sub by a magnet. The separated Pt NPs can effectively catalyze the decomposition of H2O2 to produce O2. In a sealed bottle, the pressure inside the bottle is increased by the generation of oxygen so that the water is discharged from the drainage device, and the weight of the water can be easily and precisely measured by a normal electronic balance. The weighting water has a linear relationship with the concentration of Pb2+ in the range of 2.5-100 nM and the detection limit of 0.83 nM (S/N = 3). The proposed method has been applied to detect Pb2+ in water with satisfactory results. Because the electronic balance is one of the most commonly used analytical tools for the laboratory, it is very practical and convenient without the need for expensive instruments and complicated data processing.

Homogeneous electrochemical aptasensor for mucin 1 detection based on exonuclease I-assisted target recycling amplification strategy.

A sensitive and homogeneous electrochemical aptasensor was fabricated for the detection of mucin 1 (MUC1) by combining a well-designed DNA bulge-loop (L-DNA) structure with high-efficient exonuclease I (Exo I)-assisted target recycling amplification strategy. The L-DNA probe was constructed via the hybridization of the MUC1 aptamer and methylene blue (MB) labeled complementary DNA (cDNA) (cDNA-MB) and hence could not diffuse freely to the negatively charged ITO electrode surface due to the strong electrostatic repulsion, so small electrochemical signal was detected. The addition of MUC1 caused the dissociation of L-DNA structure due to the specificity between aptamer and MUC1. Then Exo I was implemented to digest the released cDNA-MB into mononucleotides and then produced short MB-labeled mononucleotides fragments (MB-MFs). As the MB-MFs contained few negative charges, it diffused easily to the negatively charged ITO electrode surface and resulted in the enhanced electrochemical signal. Meanwhile, the MUC1-aptamer complex was also specifically digested by Exo I, resulting in the liberation of MUC1 and hence realized the target recycling and then caused the amplification of the electrochemical signal. The enhanced electrochemical signal has a good linear relationship with logarithm of MUC1 concentration in the range of 1.0 pg mL-1-50 ng mL-1 with a limit of detection of 0.40 pg mL-1 (S/N = 3). Additionally, the fabricated aptasensor has been successfully applied to detect MUC1 in serum samples with satisfactory results and thereby it exhibits great potential in the practical application of clinical diagnosis.

Kinematic and clinical analyses of upper-extremity movements after constraint-induced movement therapy in patients with stroke: a randomized controlled trial.

OBJECTIVE: To study the effects of constraint-induced movement therapy (CIMT) relative to traditional intervention on motor-control strategies for upper-arm reaching and motor performance at the impairment and functional levels in stroke patients. DESIGN: Two-group randomized controlled trial (RCT); pretreatment and posttreatment measures. SETTING: Rehabilitation clinics. PARTICIPANTS: Forty-seven stroke patients (mean age, 55y) 3 weeks to 37 months postonset of a first-ever cerebrovascular accident. INTERVENTIONS: Forty-seven patients received either CIMT (restraint of the less affected hand combined with intensive training of the more affected upper extremity) or traditional intervention (control treatment) during the study. The treatment intensity was matched between the 2 groups (2h/d, 5d/wk for 3wk). MAIN OUTCOME MEASURES: Outcomes were evaluated using (1) kinematic variables of reaching movement used to describe the control strategies for reaching, (2) the Fugl-Meyer Assessment (FMA) of motor-impairment severity, and (3) the Motor Activity Log (MAL) evaluating the functional ability of the upper extremity. RESULTS: After treatment, the CIMT group showed better strategies of reaching control than the control group (P<.03). The CIMT group also showed less motor impairment on the FMA (P=.019) and higher functional ability on the MAL (P<.001). CONCLUSIONS: This study is the first RCT to show differences in motor-control strategies as measured by kinematic variables after CIMT versus traditional intervention. In addition to improving motor performance at the impairment and functional levels, CIMT conferred therapeutic benefits on control strategies determined by kinematic analysis.