Machine learning-based mRNA signature in early acute myocardial infarction patients: the perspective toward immunological, predictive, and personalized.

Patients diagnosed with stable coronary artery disease (CAD) are at continued risk of experiencing acute myocardial infarction (AMI). This study aims to unravel the pivotal biomarkers and dynamic immune cell changes, from an immunological, predictive, and personalized viewpoint, by implementing a machine-learning approach and a composite bioinformatics strategy. Peripheral blood mRNA data from different datasets were analyzed, and CIBERSORT was used for deconvoluting human immune cell subtype expression matrices. Weighted gene co-expression network analysis (WGCNA) in single-cell and bulk transcriptome levels was conducted to explore possible biomarkers for AMI, with a particular emphasis on examining monocytes and their involvement in cell-cell communication. Unsupervised cluster analysis was performed to categorize AMI patients into different subtypes, and machine learning methods were employed to construct a comprehensive diagnostic model to predict the occurrence of early AMI. Finally, RT-qPCR on peripheral blood samples collected from patients validated the clinical utility of the machine learning-based mRNA signature and hub biomarkers. The study identified potential biomarkers for early AMI, including CLEC2D, TCN2, and CCR1, and found that monocytes may play a vital role in AMI samples. Differential analysis revealed that CCR1 and TCN2 exhibited elevated expression levels in early AMI compared to stable CAD. Machine learning methods showed that the glmBoost+Enet [alpha=0.9] model achieved high predictive accuracy in the training set, external validation sets, and clinical samples in our hospital. The study provided comprehensive insights into potential biomarkers and immune cell populations involved in the pathogenesis of early AMI. The identified biomarkers and the constructed comprehensive diagnostic model hold great promise for predicting the occurrence of early AMI and can serve as auxiliary diagnostic or predictive biomarkers.

Identification of potential serum biomarkers for congenital heart disease children with pulmonary arterial hypertension by metabonomics.

BACKGROUND: Pulmonary arterial hypertension is a common complication in patients with congenital heart disease. In the absence of early diagnosis and treatment, pediatric patients with PAH has a poor survival rate. Here, we explore serum biomarkers for distinguishing children with pulmonary arterial hypertension associated with congenital heart disease (PAH-CHD) from CHD. METHODS: Samples were analyzed by nuclear magnetic resonance spectroscopy-based metabolomics and 22 metabolites were further quantified by ultra-high-performance liquid chromatography-tandem mass spectroscopy. RESULTS: Serum levels of betaine, choline, S-Adenosyl methionine (SAM), acetylcholine, xanthosine, guanosine, inosine and guanine were significantly altered between CHD and PAH-CHD. Logistic regression analysis showed that combination of serum SAM, guanine and N-terminal pro-brain natriuretic peptide (NT-proBNP), yielded the predictive accuracy of 157 cases was 92.70% with area under the curve of the receiver operating characteristic curve value of 0.9455. CONCLUSION: We demonstrated that a panel of serum SAM, guanine and NT-proBNP is potential serum biomarkers for screening PAH-CHD from CHD.

CircUsp9x/miR-599/stim1 axis regulates proliferation and migration in vascular smooth muscle cells induced by oxidized-low density lipoprotein.

Circular RNAs (circRNAs) regulate the function of vascular smooth muscle cells (VSMCs) in atherosclerosis (AS) progression. We aimed to explore the role of circUSP9X in oxidized low-density lipoprotein (ox-LDL)-induced VSMCs. Cell proliferation was assessed using cell counting kit-8 and EDU assays. Cell migration was evaluated using Transwell and wound healing assays. The interaction between circUSP9X or STIM1 and miR-599 was analyzed using dual-luciferase reporter and RNA pull-down assays. Their levels were examined using quantitative real-time PCR. CircUSP9X and STIM1 expression was increased, whereas miR-599 expression was reduced in the serum of patients with AS and ox-LDL-stimulated VSMCs. Overexpression of circUSP9X facilitated the proliferation and migration of VSMCs induced by ox-LDL. CircUSP9X sponged miR-599, which targeted STIM1. MiR-599 reversed the effects induced by circUSP9X, and STIM1 reversed the effects induced by miR-599. Taken together, CircUSP9X promoted proliferation and migration in ox-LDL-treated VSMCs via the miR-599/STIM1 axis, providing a theoretical basis for the role of circUSP9X/miR-599/STIM1 axis in AS.

LncRNA AK087124/miR-224-5p/PTEN axis modulates endothelial cell injury in atherosclerosis through apoptosis and AKT signaling pathway.

Noncoding RNAs (ncRNAs) have been shown to play important roles in atherosclerosis-related endothelial cells dysfunction during atherosclerosis processes. In the study, our purpose was to discover new long noncoding RNAs (lncRNAs) and microRNAs (miRNAs) via competitively interacting each other to regulate the pathogenesis process of atherosclerosis. We investigated the roles of lncRNA AK087124 and miR-224-5p in atherosclerotic pathogenesis and found that AK087124 was up-regulated while miR-224-5p was down-regulated in in the plasma and plaque from atherosclerotic mice compared with normal mice. Ox-LDL was used to establish the mouse aorta endothelial cell (MAEC) injury model. The function study indicated that knockdown of AK087124 inhibited ox-LDL induced endothelial apoptosis and inflammatory response. Bioinformatic prediction combining with luciferase assays indicated that AK087124 could sponge miR-224-5p and enhance the PTEN expression which is a target of miR-224-5p. RNA pull down assays also showed that biotin-miR-224-5p probe could interacted directly with AK087124 and PTEN. Pearson correlation analysis further demonstrated that AK087124 and PTEN expression are negatively correlated with miR-224-5p. Rescue study revealed that miR-224-5p silencing and PTEN overexpression both can reverse the effect of AK087124 on the ox-LDL induced endothelial injury. These data indicated that AK087124 and miR-224-5p could be potential biomarkers and target molecules to treatment and diagnosis for atherosclerosis.

Knockdown of circ_0060745 alleviates acute myocardial infarction by suppressing NF-κB activation.

It has been shown that circRNAs are involved in the development of heart diseases. However, few studies explored the role of circRNAs in acute myocardial infarction (AMI). The present study aims to investigate the role of circ_0060745 in the pathogenesis of AMI. We found that the expression of circ_0060745 was significantly increased in the myocardium of AMI mice and was mainly expressed in myocardial fibroblasts. The knockdown of circ_0060745 decreased myocardial infarct size and improved systolic cardiac functions after AMI. The knockdown of circ_0060745 in cardiac fibroblasts inhibited the migration of peritoneal macrophage, the apoptosis of cardiomyocytes and the expressions of IL-6, IL-12, IL-1ß, TNF-α and NF-κB under hypoxia. Overexpression of circ_0060745 caused an increase in infarct size and worsened cardiac functions after AMI. In summary, our findings showed that knockdown of circ_0060745 mitigates AMI by suppressing cardiomyocyte apoptosis and inflammation. These protective effects could be attributed to inhibition of NF-κB activation.

Smart Nanosacrificial Layer on the Bone Surface Prevents Osteoporosis through Acid-Base Neutralization Regulated Biocascade Effects.

Osteoporosis is a global chronic disease characterized by severe bone loss and high susceptibility to fragile fracture. It is widely accepted that the origin acidified microenvironment created by excessive osteoclasts causes irreversible bone mineral dissolution and organic degradation during osteoclastic resorption. However, current clinically available approaches are mainly developed from the perspective of osteoclast biology rather than the critical acidified niche. Here, we developed a smart "nanosacrificial layer" consisting of sodium bicarbonate (NaHCO3)-containing and tetracycline-functionalized nanoliposomes (NaHCO3-TNLs) that can target bone surfaces and respond to external secreted acidification from osteoclasts, preventing osteoporosis. In vitro and in vivo results prove that this nanosacrificial layer precisely inhibits the initial acidification of osteoclasts and initiates a chemically regulated biocascade to remodel the bone microenvironment and realize bone protection: extracellular acid-base neutralization first inhibits osteoclast function and also promotes its apoptosis, in which the apoptosis-derived extracellular vesicles containing RANK (receptor activator of nuclear factor-κ B) further consume RANKL (RANK ligand) in serum, achieving comprehensive osteoclast inhibition. Our therapeutic strategy for osteoporosis is based on original and precise acid-base neutralization, aiming to reestablish bone homeostasis by using a smart nanosacrificial layer that is able to induce chemically regulated biocascade effects. This study also provides a novel understanding of osteoporosis therapy in biomedicine and clinical treatments.

Energetic basis for the molecular-scale organization of bone.

The remarkable properties of bone derive from a highly organized arrangement of coaligned nanometer-scale apatite platelets within a fibrillar collagen matrix. The origin of this arrangement is poorly understood and the crystal structures of hydroxyapatite (HAP) and the nonmineralized collagen fibrils alone do not provide an explanation. Moreover, little is known about collagen-apatite interaction energies, which should strongly influence both the molecular-scale organization and the resulting mechanical properties of the composite. We investigated collagen-mineral interactions by combining dynamic force spectroscopy (DFS) measurements of binding energies with molecular dynamics (MD) simulations of binding and atomic force microscopy (AFM) observations of collagen adsorption on single crystals of calcium phosphate for four mineral phases of potential importance in bone formation. In all cases, we observe a strong preferential orientation of collagen binding, but comparison between the observed orientations and transmission electron microscopy (TEM) analyses of native tissues shows that only calcium-deficient apatite (CDAP) provides an interface with collagen that is consistent with both. MD simulations predict preferred collagen orientations that agree with observations, and results from both MD and DFS reveal large values for the binding energy due to multiple binding sites. These findings reconcile apparent contradictions inherent in a hydroxyapatite or carbonated apatite (CAP) model of bone mineral and provide an energetic rationale for the molecular-scale organization of bone.

Switchable Chiral Selection of Aspartic Acids by Dynamic States of Brushite.

We herein show the chiral recognition and separation of aspartic acid (Asp) enantiomers by achiral brushite due to the asymmetries of their dynamical steps in its nonequilibrium states. Growing brushite has a higher adsorption affinity to d-Asp, while l-Asp is predominant on the dissolving brushite surface. Microstructural characterization reveals that chiral selection is mainly attributed to brushite [101] steps, which exhibit two different configurations during crystal growth and dissolution, respectively, with each preferring a distinct enantiomer due to this asymmetry. Because these transition step configurations have different stabilities, they subsequently result in asymmetric adsorption. By varying free energy barriers through solution thermodynamic driving force (i.e., supersaturation), the dominant nonequilibrium intermediate states can be switched and chiral selection regulated. This finding highlights that the dynamic steps can be vital for chiral selection, which may provide a potential pathway for chirality generation through the dynamic nature.

Evolution from Classical to Non-classical Aggregation-Based Crystal Growth of Calcite by Organic Additive Control.

Aggregation-based crystal growth is distinct from the classical understanding of solution crystallization. In this study, we reveal that N-stearoyl-l-glutamic acid (C18-Glu, an amphiphile that mimics a biomineralization-relevant biomolecule) can switch calcite crystallization from a classical ion-by-ion growth to a non-classical particle-by-particle pathway, which combines the classical and non-classical crystallization in one system. This growth mechanism change is controlled by the concentration ratio of [C18-Glu]/[Ca(2+)] in solution. The high [C18-Glu]/[Ca(2+)] can stabilize precursor nanoparticles to provide building blocks for aggregation-based crystallization, in which the interaction between C18-Glu and the nanoprecursor phase rather than that of C18-Glu on calcite steps is highlighted. Our finding emphasizes the enrollment of organic additives on metastable nano building blocks, which provides an alternative understanding about organic control in inorganic crystallization.

Realignment of Nanocrystal Aggregates into Single Crystals as a Result of Inherent Surface Stress.

Crystallization by particle attachment is widely observed in both natural and synthetic environments. Although this form of nonclassical crystallization is generally described by oriented attachment, random aggregation of building blocks to give single-crystal products is also observed, but the mechanism of crystallographic realignment is unknown. We herein reveal that random attachment during aggregation-based growth initially produces a nonoriented growth front. Subsequent evolution of the orientation is driven by the inherent surface stress applied by the disordered surface layer and results in single-crystal formation by grain-boundary migration. This mechanism is corroborated by measurements of orientation rate versus external stress, which demonstrated a predictive relationship between the two. These findings advance our understandings about aggregation-based growth via nanocrystal blocks and suggest an approach to material synthesis that takes advantage of stress-induced coalignment.

Amorphous calcium phosphate phase-mediated crystal nucleation kinetics and pathway.

Generally, a solution nucleation model is used to study biomineralization kinetics. However, we found that the amorphous calcium phosphate (ACP)-mediated hydroxyapatite (HAP) nucleation in simulated body fluids (SBF) had a different profile from the linear relationship between ln J and ln(-2) S (J, nucleation rate; S, supersaturation). This behaviour was alternatively explained by a developed heterogeneous nucleation theory, which indicated that HAP was nucleated at the ACP-solution interface via a polymorph transformation. Based upon this new model, we demonstrated experimentally that the embedded polymer molecules inside ACP were inert on HAP nucleation kinetics; rather, the polymers adsorbed on ACP surface could inhibit HAP nucleation from ACP. It further confirmed the heterogeneous nucleation pathway of HAP on the precursor phase. The present study provides an in-depth understanding of HAP formation for ACP-mediated crystallization.

Ionization controls for biomineralization-inspired CO2 chemical looping at constant room temperature.

Living organisms such as corals can carry out CO2 looping efficiently via biomineralization under ambient conditions. Inspired by this natural process, we establish a solution system of calcium acetate-ethanol-water (Ca(Ac)2-C2H5OH-H2O) for CO2 chemical looping at constant room temperature. The CO2 capture is achieved by its reaction with Ca(Ac)2 to form calcium carbonate (CaCO3) mineral and HAc in the binary solvent with a high C2H5OH content. However, an increase in the H2O content in the system triggers acetic acid (HAc)-induced CaCO3 dissolution to release CO2. The system can be recovered for CO2 capture readily by the replenishment of C2H5OH. This biomimetic mineralization-based CO2 capture/release is controlled by the ionization states of the electrolytes, and is precisely regulated in the C2H5OH-H2O binary solvent. Our attempt highlights the fundamental principle of solution chemistry in reaction control and provides a bioinspired strategy for CO2 capture/release with very low cost and easy availability.

Biomimetic construction of cellular shell by adjusting the interfacial energy.

Many unicellular organisms take their outer proteinaceous and lipidic membranes or carbonhydrate-rich cell walls as a template for biomineralization to synthesize a thin mineral layer as a functional covering. In nature most cells cannot be mineralized spontaneously in the normal states. Inspired by nature, we develop cytocompatible methods for cells encapsulated inside a mineral shell, called "cellular shellization." Using Layer-by-Layer (LbL) assembly, the precipitation of calcium minerals can be induced on the yeast cell surfaces. The effects of different synthetic polyelectrolytes on the calcifications of yeast, such as interfacial energy, zeta-potential, introduction time, and the affinity of mineral phase on the yeast cell surface have been studied by using constant composition method (CC) systemically and quantitatively. The results demonstrate that the effective adsorption of polyelectrolytes with carboxyl or sulfonate-rich groups on the yeast can enhance mineralization abilities of yeast cells readily, and the factor of interfacial energy plays a key role in the superficial mineralization of the cells. Furthermore, the influences of ion concentrations, as well as titration rates on the formation of inorganic shell, have also been examined. It is found that the biomimetic shell formation on the cell can also be achieved by using an appropriate selection of titration conditions rather than the pretreatment of LbL. Thus, the control of cellular biomineralization can become more feasible. In this study, we show that adjusting the interfacial energy is the key to cellular mineralization and suggest that these biomineralization treatments of single-cell may be applied as a potential and universal approach for cell-based sensing and therapy.

Impact of interfacial high-density water layer on accurate estimation of adsorption free energy by Jarzynski's equality.

The interactions between proteins/peptides and materials are crucial to research and development in many biomedical engineering fields. The energetics of such interactions are key in the evaluation of new proteins/peptides and materials. Much research has recently focused on the quality of free energy profiles by Jarzynski's equality, a widely used equation in biosystems. In the present work, considerable discrepancies were observed between the results obtained by Jarzynski's equality and those derived by umbrella sampling in biomaterial-water model systems. Detailed analyses confirm that such discrepancies turn up only when the target molecule moves in the high-density water layer on a material surface. Then a hybrid scheme was adopted based on this observation. The agreement between the results of the hybrid scheme and umbrella sampling confirms the former observation, which indicates an approach to a fast and accurate estimation of adsorption free energy for large biomaterial interfacial systems.

ACP-Mediated Phase Transformation for Collagen Mineralization: A New Understanding of the Mechanism.

Despite significant efforts utilizing advanced technologies, the contentious debate surrounding the intricate mechanism underlying collagen fibril mineralization, particularly with regard to amorphous precursor infiltration and phase transformation, persists. This work proposes an amorphous calcium phosphate (ACP)-mediated pathway for collagen fibril mineralization and utilizing stochastic optical reconstruction microscopy technology, and has experimentally confirmed for the first time that the ACP nanoparticles can infiltrate inside collagen fibrils. Subsequently, the ACP-mediated phase transformation occurs within collagen fibrils to form HAP crystallites, and significantly enhances the mechanical properties of the mineralized collagen fibrils compared to those achieved by the calcium phosphate ion (CPI)-mediated mineralization and resembles the natural counterpart. Furthermore, demineralized dentin can be effectively remineralized through ACP-mediated mineralization, leading to complete restoration of its mechanical properties. This work provides a new paradigm of collagen mineralization via particle-mediated phase transformation, deepens the understanding of the mechanism behind the mineralization of collagen fibrils, and offers a new strategy for hard tissue repair.

Reversion of ACP Nanoparticles into Prenucleation Clusters via Surfactant for Promoting Biomimetic Mineralization: A Physicochemical Understanding of Biosurfactant Role in Biomineralization Process.

Amphiphilic biomolecules are abundant in mineralization front of biological hard tissues, which play a vital role in osteogenesis and dental hard tissue formation. Amphiphilic biomolecules function as biosurfactants, however, their biosurfactant role in biomineralization process has never been investigated. This study, for the first time, demonstrates that aggregated amorphous calcium phosphate (ACP) nanoparticles can be reversed into dispersed ultrasmall prenucleation clusters (PNCs) via breakdown and dispersion of the ACP nanoparticles by a surfactant. The reduced surface energy of ACP@TPGS and the electrostatic interaction between calcium ions and the pair electrons on oxygen atoms of C-O-C of D-α-tocopheryl polyethylene glycol succinate (TPGS) provide driving force for breakdown and dispersion of ACP nanoparticles into ultrasmall PNCs which promote in vitro and in vivo biomimetic mineralization. The ACP@TPGS possesses excellent biocompatibility without any irritations to oral mucosa and dental pulp. This study not only introduces surfactant into biomimetic mineralization field, but also excites attention to the neglected biosurfactant role during biomineralization process.

Time evolution of moduli of a polymer-induced liquid precursor (PILP) of calcium carbonate.

In situ AFM observations show that when PILP droplets contact a surface, their initial properties are either a liquid with a high interfacial tension (350 mJ m-2) or a soft gel-like material with a low modulus (less than 0.2 MPa). These findings suggest that PILP may initially be liquid-like to infiltrate collagen fibrils, enabling the production of interpenetrating composites, and/or become viscoelastic, to provide a means for moulding minerals.

Faster nucleation at lower pH: amorphous phase mediated nucleation kinetics.

Faster nucleation of hydroxyapatite (HAP) at lower pH (with lower supersaturation) contradicts classical understanding. We find that the residue calcium ion in the mother liquor is the key to trigger ACP phase transformation, which gives an understanding of nonclassical nucleation kinetics of ACP-mediated crystallization and sheds light on biomineralization.

Progress on Biomimetic Mineralization and Materials for Hard Tissue Regeneration.

Biomineralization is a process in which natural organisms regulate the crystal growth of inorganic minerals, resulting in hierarchical structured biominerals with excellent properties. Typical biominerals in the human body are the bones and teeth, and damage to these hard tissues directly affect our daily lives. The repair of bones and teeth in a biomimetic way, either by using a biomimetic mineralization strategy or biomimetic materials, is the key for hard tissue regeneration. In this review, we briefly introduce the structure of bone and tooth, and highlight the fundamental role of collagen mineralization in tissue repair. The recent progress on intra-/extrafibrillar collagen mineralization by a biomimetic strategy or materials is presented, and their potential for tissue regeneration is discussed. Then, recent achievements on bone and tooth repair are summarized, and these works are discussed in the view of materials science and biological science, providing a broader vision for the future research of hard tissue repair techniques. Lastly, recent progress on hard tissue regeneration is concluded, and existing problems and future directions are prospected.

The application of the county medical community HCH model in postoperative nutrition management for patients with advanced gastrointestinal carcinoma.

OBJECTIVE: To investigate the application effect of the county medical community Hospital-Community health service organization-Home (HCH) model in nutritional management of patients with advanced gastrointestinal cancer after surgery. METHODS: This is a retrospective study. A total of 100 postoperative malnutrition patients with advanced gastrointestinal malignant tumors admitted to Lanxi People's Hospital from January 2022 to August 2022 were selected as subjects. All patients were divided into an observation group (n=50) or control group (n=50) according to the different methods of intervention. Patients in the observation group underwent care according to our county medical community HCH model, while those in the control group received routine perioperative nutrition management. The nutritional risk screening scores (NRS2002), Patient-Generated Subjective Global Assessment (PG-SGA) scores, body mass index (BMI), triceps skinfold thickness (TSF), upper arm circumference (AC); a well as levels of serum albumin (ALB), prealbumin (PA), transferrin (TRF), retinol binding protein (RBP), creatinine (Cr) and Free fatty acid (FFA); levels of immunoglobulin G (IgG), immunoglobulin M (IgM) and immunoglobulin A (IgA); and the levels of sodium (Na+), potassium (K+), calcium (Ca+) and lactic acid, and quality of life were recorded and compared between two groups. RESULTS: Compared with those before intervention, NRS2002 scores, PG-SGA score, BMI, TSF and AC after intervention were significantly improved in both groups. Compared with those after intervention in the control group, the NRS2002 score, PG-SGA score, BMI, TSF and AC of the patients in the observation group were significantly improved (all P<0.001). Compared with those before intervention, the levels of ALB, PA, TRF, RBP, Cr, FFA, IgG, IgM and IgA in the two groups were significantly higher after intervention. The levels of ALB, PA, TRF, RBP, Cr, FFA, IgG, IgM and IgA after intervention in the observation group were significantly higher than those in the control group (all P<0.05). Compared with those before management, the levels of Na+, K+ and lactic acid in the two groups were significantly decreased and the level of Ca+ was significantly increased after intervention. Compared with those after intervention in the control group, the patients in the observation group had significantly lower levels of Na+, K+ and lactic acid, and higher levels of Ca+ (all P<0.05). Compared with those before intervention, the scores of mental status, appetite, sleep quality, daily life and family understanding and cooperation in patients from the two groups after intervention were significantly higher. Compared with those after intervention in the control group, the patients in the observation group had significantly higher scores of life quality (P<0.05). CONCLUSION: The county medical community HCH model has a good effect in the nutritional management of patients with advanced gastrointestinal cancer surgery. The HCH model can effectively improve the nutritional status, enhance the immune function, and increase the quality of life. Thus it is worthy of clinical application.