A meta-analysis supporting the superiority of staged carotid artery stenting and coronary artery bypass grafting in patients with concurrent severe coronary and carotid artery stenosis.

BACKGROUND: This study sought to ascertain whether a staged approach involving carotid artery stenting (CAS) and coronary artery bypass grafting (CABG) holds superiority over the synchronous (Syn) strategy of CAS or carotid endarterectomy (CEA) and CABG in patients necessitating combined revascularization for concurrent carotid and coronary artery disease. METHOD: Studies were identified through 3 databases: PubMed, EMBASE, and the Cochrane Library. Statistical significance was defined as a P value of less than .05 for all analyses, conducted using STATA version 12.0. RESULTS: In the comparison between staged versus Syn CAS and CABG for patients with concomitant severe coronary and carotid stenosis, 4 studies were analyzed. The staged procedure was associated with a lower rate of 30-day stroke (OR = 8.329, 95% CI = 1.017-69.229, P = .048) compared to Syn CAS and CABG. In the comparison between staged CAS and CABG versus Syn CEA and CABG for patients with concomitant severe coronary and carotid stenosis, 5 studies were examined. The staged CAS and CABG procedure was associated with a lower rate of mortality (OR = 2.046, 95% CI = 1.304-3.210, P = .002) compared to Syn CEA and CABG. CONCLUSION: The Syn CAS and CABG was linked to a higher risk of peri-operative stroke compared to staged CAS and CABG. Additionally, patients undergoing staged CAS and CABG exhibited a significantly decreased risk of 30-day mortality compared to Syn CEA and CABG. Future randomized trials or prospective cohorts are essential to confirm and validate these findings.

Large negative differential conductance and its transformation in a single radical molecule.

The discovery of negative differential conductance (NDC) in a single molecule and mechanism controlling this phenomenon are important for molecular electronics. We investigated the electronic properties of a typical radical molecule 3-carbamoyl-2,2,5,5-tetramethyl-3-pyrrolin-1-yloxy (CTPO) on an Au(111) surface using low-temperature scanning tunneling microscopy (STM) and inelastic electron tunneling spectroscopy. Large NDC was observed in single CTPO molecules at the boundary of the crystal monolayer. The origin of observed NDC is revealed as the inelastic electron-phonon scattering during tunneling, and the strong spatial variation of the NDC over the single molecule illustrates the nature of the localized radical group. In addition, the NDC can be transformed into a positive differential conductance peak by tuning coupling strengths between different tunneling channels. An empirical multi-channel model has been developed to describe the competition between the valley-shaped NDC and peak-shaped positive differential conductance. The unique electronic property and giant conductance change observed in this radical molecule is valuable for designing novel molecular devices in the future.

Copper-Catalyzed Remote Regio- and Enantioselective Yne-Allylic Substitution of Coumarins.

Chiral coumarins and their derivatives are prominent bioactive structural units present in a wide range of natural products and pharmaceutical candidates. Therefore, the development of straightforward and efficient methodologies for the synthesis of readily functionalized chiral coumarins is of significant interest. Herein we report an enantioselective copper-catalyzed yne-allylic substitution of coumarins, resulting in a highly regioselective synthesis of diverse new classes of chiral coumarin derivatives with high efficiency and excellent functional group tolerance. Subsequent versatile transformations further demonstrate the substantial synthetic potential of this strategy in the field of biochemical research.

Identification of lignans as selective cyclooxygenase-2 inhibitors from the extract of Acanthopanacis cortex.

Acanthopanacis cortex (the dried root bark of Acanthopanax gracilistylus W. W. Smith) has been used for the treatment of rheumatic diseases in China for over 2000 years. Four previously undescribed lignans (1-4) and 12 known lignans (5-16) were isolated from Acanthopanacis cortex. In this study, the inhibitory activities of compounds 1-16 against neutrophil elastase (NE), cyclooxygenase-1 (COX-1) and cyclooxygenase-2 (COX-2) are reported. The results show that compounds 1-16 exhibit weak inhibitory activities against NE and COX-1. However, compounds 2, 6-8 and 13-16 demonstrate better COX-2 inhibitory effects with IC50 values from 0.75 to 8.17 µΜ. These findings provide useful information for the search for natural selective COX-2 inhibitors.

Engineered AAV13 variants with enhanced transduction and confined spread.

Precise targeting of specific regions within the central nervous system (CNS) is crucial for both scientific research and gene therapy in the context of brain diseases. Adeno-associated virus 13 (AAV13) is known for its restricted diffusion range within the CNS, making it an ideal choice for precise labeling and administration within small brain regions. However, AAV13 mediates relatively low expression of target genes. Here, we introduced specifically engineered modifications to the AAV13 capsid protein to enhance its transduction efficiency. We first constructed AAV13-YF by mutating tyrosine to phenylalanine on the surface of the AAV13 capsid. We then inserted the 7m8 peptide, known to enhance cell transduction, into positions 587/588 and 585/586 of the AAV13 capsid, resulting in two distinct variants named AAV13-587-7m8 and AAV13-585-7m8, respectively. We found that AAV13-YF exhibited superior in vitro infectivity in HEK293T cells compared to AAV13, while AAV13-587-7m8 and AAV13-585-7m8 showed enhanced CNS infection capabilities in C57BL/6 mice, with AAV13-587-7m8 infection retaining a limited spread range. These modified AAV13 variants hold promising potential for applications in gene therapy and neuroscience research.

Preparation, Structures, Photoluminescence and Semiconductive Properties of Two Novel Lanthanide Mercury Materials with a 3-D Framework Structure.

Two novel lanthanide mercury materials, [Gd(IA)3(H3O)2Hg3Br6]n·2nCl (1) and [La(IA)3(H3O)2Hg3Br6]n·2nCl (2) (IA = isonicotinic anion), have been prepared under solvothermal conditions and characterized by single-crystal X-ray diffraction techniques. They are isomorphic and characterized by a three-dimensional (3-D) framework structure. The lanthanide ions are bound by eight oxygen atoms to exhibit a square antiprismatic geometry. The solid-state photoluminescence experiment discovers that compound 1 shows a strong emission in the red region. Compound 1 possesses CIE (Commission Internationale de I'Éclairage) chromaticity coordinates of 0.7347 and 0.2653. Its CCT (correlated color temperature) is 6514 K. Compound 2 displays yellow photoluminescence and it has CIE chromaticity coordinates of 0.4411 and 0.5151. The CCT of compound 2 is 3633 K. Solid-state UV/Vis diffuse reflectance spectra revealed that their semiconductor band gaps are 2.16 eV and 2.85 eV, respectively.

Screening of environmental stimuli for the positive regulation of stomatal aperture in centipedegrass.

Grasslands, the largest carbon pool in China, possess enormous potential for carbon sequestration. Increasing the stomatal aperture to increase the CO2 absorption capacity is a potential method to improve plant photosynthetic efficiency and ultimately enhance the carbon sequestration capacity of grass plants. Research on stomatal aperture regulation has focused mostly on Arabidopsis or crops, while research on grass plants in these areas is scarce, which seriously restricts the implementation of this grassland carbon sequestration strategy. Here, a widely used ecological grass, centipedegrass, was used as the experimental material. First, a convenient method for observing the stomatal aperture was developed. The leaves were floated in a potassium ion-containing open solution (67 mM KCl, pH 6.0) with the adaxial surface rather than the abaxial surface in contact with the solution and were cultivated under light for 1.5 h. Then, nail polish was applied on the adaxial surface, and a large number of open stomata were imprinted. Second, with the help of this improved method, the concentration‒response characteristics of the stomatal aperture to eleven environmental stimuli were tested. The stomatal aperture is dependent on these environmental stimuli in a concentration-dependent manner. The addition of 100 µM brassinolide led to the maximal stomatal aperture. This study provided a technical basis for manipulating stomatal opening to increase the carbon sequestration capacity of centipedegrass.

Diterpenoids from Acanthopanacis Cortex and their anti-inflammatory activity studies.

Acanthopanacis Cortex (A.-C) with a long history of more than1000 years, has been used to treat rheumatism effectively. Nineteen diterpenoids have been isolated from A.-C, including six new compounds (1-6). Among them, compounds 7, 9-11, 13, and 17 were discovered from A.-C for the first time. The structures of 1-6 were determined by analyzing their NMR data and comparing their experimental and calculated electronic circular dichroism spectra. Moreover, the single-crystal X-ray diffraction data of 1, 2, 8, and 14 were provided. The anti-inflammatory activity of 1-5 and 7-18 on neutrophil elastase, cyclooxygenase-1 (COX-1), and cyclooxygenase-2 (COX-2) has been studied in vitro, and the results showed that 15 had almost no inhibitory effects on COX-1 at 200 µM but a significant activity against COX-2 with an IC50 of 0.73 ± 0.006 µΜ. It indicated that compound 15 can provide valuable information for the design of selective COX-2 inhibitors.

[Preparation of recombinant mussel mucin Mfp-3P and its promotion of wound healing].

To investigate the role of recombinant mussel mucin in wound healing, we aimed to prepare this mucin using Pichia pastoris as the host microbe. Our method involved constructing a genetically engineered strain of P. pastoris that expressed a fusion protein consisting of Mfp-3 and preCol-P peptide segments of mussel. After fermentation and purification, we obtained a pure recombinant mussel mucin product. We then conducted experiments to evaluate its effect at both the cellular and animal levels. At the cellular level, we examined its impact on the proliferation and migration of mouse fibroblast L929. At the animal level, we assessed its ability to promote wound healing after full-layer skin resection in rats. Our results showed that the recombinant mussel mucin protein has a content of 90.28% and a purity of 96.49%. The content of 3,4-dihydroxyphenylalanine (DOPA) was 0.73 wt%, and the endotoxin content was less than 0.5 EU/mg. Importantly, the recombinant mussel mucin protein significantly promoted both the migration and proliferation of mouse fibroblast, as well as the wound healing in rat skin. In conclusion, our findings demonstrate that recombinant mussel mucin has the potential to promote wound healing and can be considered a promising medical biomaterial.

A new perspective on prostate cancer treatment: the interplay between cellular senescence and treatment resistance.

The emergence of resistance to prostate cancer (PCa) treatment, particularly to androgen deprivation therapy (ADT), has posed a significant challenge in the field of PCa management. Among the therapeutic options for PCa, radiotherapy, chemotherapy, and hormone therapy are commonly used modalities. However, these therapeutic approaches, while inducing apoptosis in tumor cells, may also trigger stress-induced premature senescence (SIPS). Cellular senescence, an entropy-driven transition from an ordered to a disordered state, ultimately leading to cell growth arrest, exhibits a dual role in PCa treatment. On one hand, senescent tumor cells may withdraw from the cell cycle, thereby reducing tumor growth rate and exerting a positive effect on treatment. On the other hand, senescent tumor cells may secrete a plethora of cytokines, growth factors and proteases that can affect neighboring tumor cells, thereby exerting a negative impact on treatment. This review explores how radiotherapy, chemotherapy, and hormone therapy trigger SIPS and the nuanced impact of senescent tumor cells on PCa treatment. Additionally, we aim to identify novel therapeutic strategies to overcome resistance in PCa treatment, thereby enhancing patient outcomes.

Large-scale research on durability test cycle of fuel cell system based on CATC.

Durability is one of the technical bottlenecks restricting fuel cell electric vehicle development. As a result, significant time and resources have been invested in research related to this area worldwide. Current durability research mainly focuses on the single cell and stack levels, which is quite different from the usage scenarios of actual vehicles. There is almost no research on developing durability test cycles on the fuel cell system level. This paper proposes a universal model for developing a durability test cycle for fuel cell system based on the China automotive test cycle. Large-scale comparison tests of the fuel cell systems are conducted. After 1000 h test, the output performance degradation of three mass-produced fuel cell system is 14.49%, 9.59%, and 4.21%, respectively. The test results show that the durability test cycle proposed in this paper can effectively accelerate the durability test of the fuel cell system and evaluate the durability performance of the fuel cell system. Moreover, the methodology proposed in this paper could be used in any other test cycles such as NEDC (New European Driving Cycle), WLTC (Worldwide Harmonized Light Vehicles Test Procedure), etc. And it has comprehensive application value and are significant for reducing the cost of durability testing of fuel cell systems and promoting the industrialization of fuel cell electric vehicles.

Enhanced cellular therapy: revolutionizing adoptive cellular therapy.

Enhanced cellular therapy has emerged as a novel concept following the basis of cellular therapy. This treatment modality applied drugs or biotechnology to directly enhance or genetically modify cells to enhance the efficacy of adoptive cellular therapy (ACT). Drugs or biotechnology that enhance the killing ability of immune cells include immune checkpoint inhibitors (ICIs) / antibody drugs, small molecule inhibitors, immunomodulatory factors, proteolysis targeting chimera (PROTAC), oncolytic virus (OV), etc. Firstly, overcoming the inhibitory tumor microenvironment (TME) can enhance the efficacy of ACT, which can be achieved by blocking the immune checkpoint. Secondly, cytokines or cytokine receptors can be expressed by genetic engineering or added directly to adoptive cells to enhance the migration and infiltration of adoptive cells to tumor cells. Moreover, multi-antigen chimeric antigen receptors (CARs) can be designed to enhance the specific recognition of tumor cell-related antigens, and OVs can also stimulate antigen release. In addition to inserting suicide genes into adoptive cells, PROTAC technology can be used as a safety switch or degradation agent of immunosuppressive factors to enhance the safety and efficacy of adoptive cells. This article comprehensively summarizes the mechanism, current situation, and clinical application of enhanced cellular therapy, describing potential improvements to adoptive cellular therapy.

Mitofilin in cardiovascular diseases: Insights into the pathogenesis and potential pharmacological interventions.

The impact of mitochondrial dysfunction on the pathogenesis of cardiovascular disease is increasing. However, the precise underlying mechanism remains unclear. Mitochondria produce cellular energy through oxidative phosphorylation while regulating calcium homeostasis, cellular respiration, and the production of biosynthetic chemicals. Nevertheless, problems related to cardiac energy metabolism, defective mitochondrial proteins, mitophagy, and structural changes in mitochondrial membranes can cause cardiovascular diseases via mitochondrial dysfunction. Mitofilin is a critical inner mitochondrial membrane protein that maintains cristae structure and facilitates protein transport while linking the inner mitochondrial membrane, outer mitochondrial membrane, and mitochondrial DNA transcription. Researchers believe that mitofilin may be a therapeutic target for treating cardiovascular diseases, particularly cardiac mitochondrial dysfunctions. In this review, we highlight current findings regarding the role of mitofilin in the pathogenesis of cardiovascular diseases and potential therapeutic compounds targeting mitofilin.

Analysis of Factors Influencing Prognosis and Assessment of 60 Cases of Decompensated Cirrhotic Patients with Portal Hypertension.

Objective: To investigate the risk factors for the development of portal hypertension in patients with decompensated cirrhosis and analyze their prognosis. Methods: Patients with decompensated cirrhosis who were admitted to our hospital and Qu fu People's Hospital from June 2022 to June 2023 were included in this study. Among them, there were 45 male and 15 female patients, with a median age of 56 (range: 35-77) years. A comparative analysis was performed between Group A (hepatic venous pressure gradient, HVPG <16 mmHg) and Group B (HVPG ≥16 mmHg) patients, along with various clinical outcomes. Multivariate analysis was conducted to explore the risk factors influencing the occurrence of portal hypertension and adverse prognosis in patients with cirrhosis. Results: In Group A patients with portal hypertension, we observed lower levels of aspartate aminotransferase, laminin, serum hyaluronic acid, type III procollagen N-terminal peptide, total bile acids, and cholylglycine acid compared to Group B. On the other hand, levels of alanine aminotransferase, white blood cells, and serum albumin were higher in Group A than in Group B. These differences between the groups were statistically significant (P < 0.05). Multivariate analysis of the aforementioned risk factors indicated that low white blood cell count, high cholylglycine acid levels, and high serum hyaluronic acid levels were identified as independent risk factors for the occurrence of difficult-to-control complications in decompensated portal hypertension among patients with liver cirrhosis (P < 0.05). Conclusion: Liver cirrhosis patients with portal hypertension and multiple risk factors like low white blood cell count and high liver transaminase levels should be cautious regarding the progression of portal hypertension when combined with splenomegaly, liver fibrosis, and bile stasis, as it often indicates a poor prognosis.

Geographic differences in psychological symptoms, sleep quality, and quality of life in patients with inflammatory bowel disease: A multicenter study in China.

OBJECTIVE: We aimed to explore the geographic differences in psychological symptoms, sleep quality, and quality of life (QoL) among adult patients with inflammatory bowel disease (IBD). METHODS: A unified questionnaire was developed to collect data on psychological status and QoL of IBD patients from 42 hospitals across 22 provinces, municipalities, and autonomous regions in China's mainland from September 2021 to May 2022. RESULTS: A total of 2478 patients with IBD were surveyed. The proportions of patients with anxiety (28.5% vs 23.1%), depression (32.3% vs 27.8%), and poor QoL (44.8% vs 32.2%) were significantly higher in patients from the northern region compared to the southern region (all P < 0.05). In the western region, the proportions of patients with anxiety (31.9% vs 23.0%), depression (37.7% vs 26.7%), sleep disturbances (64.5% vs 58.5%), and poor QoL (44.9% vs 34.8%) were significantly higher than in the eastern and central regions (all P < 0.01). Patients from inland regions had significantly higher rates of anxiety (27.1% vs 23.3%), depression (32.5% vs 26.0%), sleep disturbance (62.0% vs 57.7%), and poor QoL (43.5% vs 29.9%) compared to those from coastal regions (all P < 0.05). In economically underdeveloped areas, the proportions of patients with depression (33.1% vs 28.5%) and poor QoL (52.0% vs 32.4%) were significantly higher than in economically (relatively) developed areas (both P < 0.05). CONCLUSION: There are significant geographic differences in psychological symptoms, sleep quality, and QoL among Chinese patients with IBD, which might provide valuable insights for global IBD research and clinical practice.

Pan-cancer analysis of NUP155 and validation of its role in breast cancer cell proliferation, migration, and apoptosis.

NUP155 is reported to be correlated with tumor development. However, the role of NUP155 in tumor physiology and the tumor immune microenvironment (TIME) has not been previously examined. This study comprehensively investigated the expression, immunological function, and prognostic significance of NUP155 in different cancer types. Bioinformatics analysis revealed that NUP155 was upregulated in 26 types of cancer. Additionally, NUP155 upregulation was strongly correlated with advanced pathological or clinical stages and poor prognosis in several cancers. Furthermore, NUP155 was significantly and positively correlated with DNA methylation, tumor mutational burden, microsatellite instability, and stemness score in most cancers. Additionally, NUP155 was also found to be involved in TIME and closely associated with tumor infiltrating immune cells and immunoregulation-related genes. Functional enrichment analysis revealed a strong correlation between NUP155 and immunomodulatory pathways, especially antigen processing and presentation. The role of NUP155 in breast cancer has not been examined. This study, for the first time, demonstrated that NUP155 was upregulated in breast invasive carcinoma (BRCA) cells and revealed its oncogenic role in BRCA using molecular biology experiments. Thus, our study highlights the potential value of NUP155 as a biomarker in the assessment of prognostic prediction, tumor microenvironment and immunotherapeutic response in pan-cancer.

Knowledge mapping of application of image-guided surgery in prostate cancer: a bibliometric analysis (2013-2023).

BACKGROUND: Image-guided surgery (IGS) refers to surgery navigated by medical imaging technology, helping doctors better clarify tumor boundaries, identify metastatic lymph nodes and preserve surrounding healthy tissue function. Recent studies have provided expectable momentum of the application of IGS in prostate cancer (PCa). The authors aim to comprehensively construct a bibliometric analysis of the application of IGS in PCa. METHOD: The authors searched publications related to application of IGS in PCa from 2013 to 2023 on the web of science core collection (WoSCC) databases. VOSviewer, CiteSpace, and R package 'bibliometrix' were used for bibliometric analysis. RESULTS: Two thousand three eighty-nine articles from 75 countries and 2883 institutions led by the United States were included. The number of publications related to the application of IGS in PCa kept high in the last decade. Johns Hopkins University is the top research institutions. Journal of Nuclear Medicine has the highest popularity as the selection of journal and co-cited journal. Pomper Martin G. had published the most paper. Ali Afshar-Oromieh was co-cited most frequently. The clinical efficacy of PSMA-PET/CT in PCa diagnosis and treatment are main topics in this research field, with emerging focuses on the use of fluorescence imaging guidance technology in PCa. 'PSMA' and 'PET/CT' are the main keywords as long-term research hotspots. CONCLUSION: This study is the first bibliometric analysis of researches on application of IGS in PCa with three recognized bibliometric software, providing an objective description and comprehensive guidance for the future relevant investigations.

Sivelestat in Patients at a High Risk of Postoperative Acute Lung Injury After Scheduled Cardiac Surgery: A Prospective Cohort Study.

Background: Sivelestat, a neutrophil elastase inhibitor, is specifically developed to mitigate the occurrence of acute lung injury (ALI) in individuals who are undergoing cardiovascular surgery. However, its impact on patients who are at a heightened risk of developing ALI after scheduled cardiac surgery has yet to be determined. In order to address this knowledge gap, we undertook a study to assess the efficacy of sivelestat in protecting the lungs of these patients. Methods: We conducted a prospective cohort study involving 718 patients who were at high risk of developing postoperative acute lung injury (ALI) and underwent scheduled cardiac surgery between April 25th, 2022, and September 7th, 2023. Among them, 52 patients received sivelestat (administered at a dosage of 0.2mg/kg/h for 3 days), while 666 patients served as controls, not receiving sivelestat. The control conditions were the same for all patients, including ventilation strategy, extubating time, and fluid management. Subsequently, a propensity-score matched cohort was established, consisting of 40 patients in both the sivelestat and control groups. The primary outcome measure encompassed a composite of adverse outcomes, including 30-day mortality, ALI, acute respiratory distress syndrome (ARDS), and others. Secondary outcomes assessed included pneumonia, ventricular arrhythmias, mechanical ventilation (MV) time, and more. Results: After conducting propensity matching in our study, we observed that there were no significant differences in 30-day mortality between the sivelestat and control groups (0% vs 2.5%, P=0.32). However, the use of sivelestat exhibited a significant reduction in the incidence of acute lung injury/acute respiratory distress syndrome (ALI/ARDS) compared to the control group (0% vs 55%, P<0.01), pneumonia (0 vs 37.5%, P<0.01), MV time (median:8 hours, IQR:4-14.8 hours vs median: 15.2 hours, IQR:14-16.3 hours, P<0.01). Compared to the control group, the sivelestat could significantly decrease white cell count (P<0.01), neutrophile percentage (P<0.01) and C-reactive protein (P<0.01) in the period of postoperative 5 days. Conclusion: The prophylactic administration of sivelestat has shown promising results in reducing the occurrence of acute lung injury/acute respiratory distress syndrome (ALI/ARDS) in patients with a heightened risk of developing these conditions after elective cardiac surgery. Our study findings indicate that sivelestat may provide protective effects by suppressing inflammation triggered by neutrophil activation, thereby safeguarding pulmonary function. Registration: ChiCTR2200059102, https://www.chictr.org.cn/showproj.html?proj=166643.

MSWIFA and cement cooperate in the disposal of soft soil - experimental study on silty sand and silty clay.

Municipal solid waste incineration fly ash (MSWIFA) can be reused as a positive additive to strengthen soft soil. In this study, MSWIFA was initially used as a supplementary solidification material in combination with ordinary Portland cement to prepare fly ash cement-stabilized soil (FACS) with silty sand and silty clay, respectively. The ratio of MWSIFA to total mass was 5%, 10%, and 15%, and the cement content was set as 10% and 15%. The mechanical properties of FACS were evaluated by unconfined compressive strength test. The heavy metal-leaching test was conducted to estimate the environmental risk of FACS. The scanning electron microscope was used to test the micro-structure of FACS. The X-ray diffraction was performed to analyze material composition of FACS. The result indicates that the collaborative solidification of soft soil with MSWIFA and cement is feasible. Regarding the silty clay, the FA had positive effects on the silty clay in the service age (between 50 and 100% with 15% MSWIFA), as the MSWIFA reformulated the initial silty clay structure, resulting in interconnection and pore fill between particles. It can be founded that C-S-H and ettringite are the main products of MSWIFA and cement hydration, which are formed by the hydration of C3S and C2S. Regarding the silty sand, the MSWIFA decreased the peak strength (between 35 and 48% with 15% MSWIFA) but increased the ductility of the stabilized cement. Under the same mix proportions, the leaching toxicities of Zn and Pb in FACS of silty clay were obviously lower than were those of silty sand. Generally, the leaching concentrations of tested metals under all the mix proportions were well below the limit value set by GB 18598-2019 for hazardous waste landfill. Thus, the reuse of MSWIFA in cement-stabilized soil would be one of the effective methods in soft soil treatment and solid waste reduction.

Biomimetic Self-Maturation Mineralization System for Enamel Repair.

Enamel repair is crucial for restoring tooth function and halting dental caries. However, contemporary research often overlooks the retention of organic residues within the repair layer, which hinders the growth of dense crystals and compromises the properties of the repaired enamel. During the maturation of natural enamel, the organic matrix undergoes enzymatic processing to facilitate further crystal growth, resulting in a highly mineralized tissue. Inspired by this process, a biomimetic self-maturation mineralization system is developed, comprising ribonucleic acid-stabilized amorphous calcium phosphate (RNA-ACP) and ribonuclease (RNase). The RNA-ACP induces initial mineralization in the form of epitaxial crystal growth, while the RNase present in saliva automatically triggers a biomimetic self-maturation process. The mechanistic study further indicates that RNA degradation prompts conformational rearrangement of the RNA-ACP, effectively excluding the organic matter introduced earlier. This exclusion process promotes lateral crystal growth, resulting in the generation of denser enamel-like apatite crystals that are devoid of organic residues. This strategy of eliminating organic residues from enamel crystals enhances the mechanical and physiochemical properties of the repaired enamel. The present study introduces a conceptual biomimetic mineralization strategy for effective enamel repair in clinical practice and offers potential insights into the mechanisms of biomineral formation.