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1.
Angew Chem Int Ed Engl ; : e202403391, 2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38717757

RESUMEN

Room temperature phosphorescence (RTP) materials have garnered significant attention owing to its distinctive optical characteristics and broad range of potential applications. However, the challenge remains in producing RTP materials with more simplicity, versatility, and practicality on a large scale, particularly in achieving chiral signals within a single system. Herein, we show that a straightforward and effective combination of wet spinning and twisting technique enables continuously fabricating RTP fibers with twisting-induced helical chirality. By leveraging the hydrogen bonding interactions between polyvinyl alcohol (PVA) and quinoline derivatives, along with the rigid microenvironment provided by PVA chains, typically, Q-NH2@PVA fiber demonstrates outstanding phosphorescent characteristics with RTP lifetime of 1.08 s and phosphorescence quantum yield of 24.6%, and the improved tensile strength being 1.7 times than pure PVA fiber (172 ± 5.82 vs 100 ± 5.65 MPa). Impressively, the transformation from RTP to circularly polarized room temperature phosphorescence (CP-RTP) is readily achieved by imparting left- or right-hand helical structure through simply twisting, enabling large-scale production of chiral Q-NH2@PVA fiber with dissymmetry factor of 10-2. Besides, an array of displays and encryption patterns are crafted by weaving or seaming to exemplify the promising applications of these PVA-based fibers with outstanding adaptivity in cutting-edge anti-counterfeiting technology.

2.
Polymers (Basel) ; 16(9)2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38732663

RESUMEN

The research used polyethersulfone (PES) as a membrane material, polyvinylpyrrolidone (PVP) k30 and polyethylene glycol 400 (PEG 400) as water-soluble additives, and dimethylacetamide (DMAc) as a solvent to prepare hollow-fiber ultrafiltration membranes through a nonsolvent-induced phase separation (NIPS) process. The hydrophilic nature of PVP-k30 and PEG caused them to accumulate on the membrane surface during phase separation. The morphology, chemical composition, surface charge, and pore size of the PES membranes were evaluated by SEM, FTIR, zeta potential, and dextran filtration experiments. The paper also investigated how different spinning solution compositions affected membrane morphology and performance. The separation efficiency of membranes with four different morphologies was tested in single-protein and double-protein mixed solutions. The protein separation effectiveness of the membrane was studied through molecular weight cutoff, zeta potential, and static protein adsorption tests. In addition, the operating pressure and pH value were adjusted to improve ultrafiltration process conditions. The PES membrane with an intact sponge-like structure showed the highest separation factor of 11, making it a prime candidate membrane for the separation of bovine serum albumin (BSA) and lysozyme (LYS). The membrane had a minimal static protein adsorption capacity of 48 mg/cm2 and had excellent anti-fouling properties. When pH = 4, the BSA retention rate was 93% and the LYS retention rate was 23%. Furthermore, it exhibited excellent stability over a pH range of 1-13, confirming its suitability for protein separation applications.

3.
ACS Appl Mater Interfaces ; 16(21): 27794-27803, 2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38748448

RESUMEN

The development of optical humidity detection has been of considerable interest in highly integrated wearable electronics and packaged equipment. However, improving their capacities for color recognition at ultralow humidity and response-recovery rate remains a significant challenge. Herein, we propose a type of hybrid water-harvesting channel to construct brand-new passive fluorescence humidity sensors (PFHSs). Specifically, the hybrid water-harvesting channels involve porous metal-organic frameworks and a hydrophilic poly(acrylic acid) network that can capture water vapors from the ambient environment even at ultralow humidity, into which polar-responsive aggregation-induced emission molecules are doped to impart humidity-sensitive luminescence colors. As a result, the PFHSs exhibit clearly defined fluorescence signals within 0-98% RH coupling with desirable performances such as a fast response rate, precise quantitative feedback, and durable reversibility. Given the flexible processability of this system, we further upgrade the porous structure via electrostatic spinning to furnish a kind of Nano-PFHSs, demonstrating an impressive response time (<100 ms). Finally, we validate the promising applications of these sensors in electronic humidity monitoring and successfully fabricate a portable and rapid humidity indicator card.

4.
Micromachines (Basel) ; 15(5)2024 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-38793217

RESUMEN

In this article, we demonstrate a high-energy, wide-spectrum, spatiotemporal mode-locked (STML) fiber laser. Unlike traditional single-mode fiber lasers, STML fiber lasers theoretically enable mode-locking with various combinations of transverse modes. The laser can deliver two different STML pulse sequences with different pulse widths, spectra and beam profiles, due to the different compositions of transverse modes in the output pulses. Moreover, we achieve a wide-spectrum pulsed output with a single-pulse energy of up to 116 nJ, by weakening the spectral filtering and utilizing self-cleaning. Strong spatial and spectral filtering are usually thought to be necessary for achieving STML. Our experiment verifies the necessity of spatial filtering for achieving STML, and we show that weakening unnecessary spectral filtering provides an effective way to increase the pulse energy and spectrum width of mode-locked fiber lasers.

5.
BMC Neurol ; 24(1): 134, 2024 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-38641592

RESUMEN

BACKGROUND: Although contrast extravasation on follow-up head computed tomography (CT) is frequently visualized after endovascular treatment, this phenomenon is rare after intravenous thrombolytic treatment in patients with acute ischemic stroke (AIS). Here, we report a case of contrast extravasation mimicking intracerebral hemorrhage (ICH) with intraventricular extension after intravenous thrombolytic treatment and computed tomography angiography (CTA). CASE PRESENTATION: A 52-year-old man presented with right-sided hemiparesis and hypoesthesia. Initial non-contrast head CT was negative for intracranial hemorrhage and acute ischemic changes. He received intravenous treatment with tenecteplase 3.8 h after the onset of stroke. CTA of the head and neck was performed at 4.3 h after stroke onset. It showed no stenosis or occlusion of the carotid and major intracranial arteries. At about 1.5 h after CTA, the right-sided hemiparesis deteriorated, accompanied by drowsiness, aphasia, and urinary incontinence. Immediate head CT showed hyperdense lesions with mild space-occupying effect in the left basal ganglia and both lateral ventricles. The hyperdense lesions were reduced in size on follow-up CT after 5 h. Two days later, CT showed that the hyperdense lesions in the lateral ventricles almost completely disappeared and only a small amount remained in the infarcted area. CONCLUSIONS: Contrast extravasation into the brain tissue and lateral ventricles, mimicking ICH with intraventricular extension, could occur after intravenous thrombolytic treatment and CTA in a patient with AIS, which might lead to misdiagnosis and wrong treatment of the patient. The rapid resolution of intracranial hyperdense lesions is key to differentiate contrast extravasation from ICH on serial non-enhanced CT.


Asunto(s)
Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Masculino , Humanos , Persona de Mediana Edad , Accidente Cerebrovascular Isquémico/tratamiento farmacológico , Hemorragia Cerebral/diagnóstico , Hemorragia Cerebral/diagnóstico por imagen , Fibrinolíticos/efectos adversos , Accidente Cerebrovascular/diagnóstico por imagen , Accidente Cerebrovascular/tratamiento farmacológico , Extravasación de Materiales Terapéuticos y Diagnósticos/complicaciones , Extravasación de Materiales Terapéuticos y Diagnósticos/tratamiento farmacológico , Paresia
6.
BMJ Open ; 14(4): e079370, 2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38670618

RESUMEN

INTRODUCTION: Myocardial injury is a relatively common complication of traumatic brain injury (TBI). However, the incidence and clinical impact of myocardial injury characterised by elevated cardiac troponin (cTn) levels after TBI are still poorly known. The objective of our study is to assess the global incidence of myocardial injury characterised by elevated cTn in adult patients with TBI and its association with in-hospital mortality. METHODS AND ANALYSIS: The protocol of our systematic review and meta-analysis is performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Protocols guidelines. We will search the Medline, Embase, Cochrane Library, Scopus and Web of Science databases from inception to 1 January 2024, for observational studies in any language that reported the incidence of elevated cTn and/or in-hospital mortality associated with elevated cTn among adult patients with TBI. Two reviewers will independently assess study eligibility, extract the data and assess the risk of bias. ORs and 95% CIs will be used with a random-effects or fixed-effects model according to the estimated heterogeneity among studies assessed by the I2 index. We will perform a quantitative synthesis for the incidence of elevated cTn and in-hospital mortality data. If sufficient data are available, we will perform subgroup analysis and meta-regression to address the heterogeneity. In addition, we will perform a narrative analysis if quantitative synthesis is not appropriate. ETHICS AND DISSEMINATION: Ethics approval was not required for this study. We intend to publish our findings in a high-quality, peer-reviewed journal. PROSPERO REGISTRATION NUMBER: CRD42023454686.


Asunto(s)
Lesiones Traumáticas del Encéfalo , Mortalidad Hospitalaria , Metaanálisis como Asunto , Revisiones Sistemáticas como Asunto , Humanos , Lesiones Traumáticas del Encéfalo/mortalidad , Lesiones Traumáticas del Encéfalo/sangre , Lesiones Traumáticas del Encéfalo/complicaciones , Incidencia , Troponina/sangre , Troponina/metabolismo , Proyectos de Investigación , Adulto
8.
BMC Cancer ; 24(1): 276, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38424484

RESUMEN

BACKGROUND: Adenosine monophosphate-activated protein kinase (AMPK) is associated with the development of liver hepatocellular carcinoma (LIHC). AMPKα2, an α2 subunit of AMPK, is encoded by PRKAA2, and functions as the catalytic core of AMPK. However, the role of AMPKα2 in the LIHC tumor immune environment is unclear. METHODS: RNA-seq data were obtained from the Cancer Genome Atlas and Genotype-Tissue Expression databases. Using the single-cell RNA-sequencing dataset for LIHC obtained from the China National Genebank Database, the communication between malignant cells and T cells in response to different PRKAA2 expression patterns was evaluated. In addition, the association between PRKAA2 expression and T-cell evolution during tumor progression was explored using Pseudotime analysis, and the role of PRKAA2 in metabolic reprogramming was explored using the R "scMetabolis" package. Functional experiments were performed in LIHC HepG2 cells. RESULTS: AMPK subunits were expressed in tissue-specific and substrate-specific patterns. PRKAA2 was highly expressed in LIHC tissues and was associated with poor patient prognosis. Tumors with high PRKAA2 expression displayed an immune cold phenotype. High PRKAA2 expression significantly promoted LIHC immune escape. This result is supported by the following evidence: 1) the inhibition of major histocompatibility complex class I (MHC-I) expression through the regulation of interferon-gamma activity in malignant cells; 2) the promotion of CD8+ T-cell exhaustion and the formation of CD4+ Treg cells in T cells; 3) altered interactions between malignant cells and T cells in the tumor immune environment; and 4) induction of metabolic reprogramming in malignant cells. CONCLUSIONS: Our study indicate that PRKAA2 may contribute to LIHC progression by promoting metabolic reprogramming and tumor immune escape through theoretical analysis, which offers a theoretical foundation for developing PRKAA2-based strategies for personalized LIHC treatment.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Proteínas Quinasas Activadas por AMP , Carcinoma Hepatocelular/genética , Linfocitos T CD4-Positivos , Linfocitos T CD8-positivos , Neoplasias Hepáticas/genética , Agotamiento de Células T , Linfocitos T Reguladores , Escape del Tumor
9.
J Orthop Surg Res ; 19(1): 31, 2024 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-38178210

RESUMEN

BACKGROUND: Osteoarthritis is a prevalent degenerative joint condition typically found in individuals who are aged 50 years or older. In this study, the focus is on PIWI-interacting RNA (piRNA), which belongs to a category of small non-coding RNAs. These piRNAs play a role in the regulation of gene expression and the preservation of genomic stability. The main objective of this research is to examine the expression of a specific piRNA called hsa_piR_019949 in individuals with osteoarthritis, to understand its impact on chondrocyte metabolism within this condition. METHODS: We analyzed piRNA expression in osteoarthritis cartilage using the GEO database. To understand the impact of inflammatory factors on piRNA expression in chondrocytes, we conducted RT-qPCR experiments. We also investigated the effect of piRNA hsa_piR_019949 on chondrocyte proliferation using CCK-8 and clone formation assays. Furthermore, we assessed the influence of piRNA hsa_piR_019949 on chondrocyte apoptosis by conducting flow cytometry analysis. Additionally, we examined the differences in cartilage matrix composition through safranine O staining and explored the downstream regulatory mechanisms of piRNA using transcriptome sequencing. Lentiviral transfection of NEAT1 and NLRP3 was performed to regulate the metabolism of chondrocytes. RESULTS: Using RNA sequencing technology, we compared the gene expression profiles of 5 patients with osteoarthritis to 3 normal controls. We found a gene called hsa_piR_019949 that showed differential expression between the two groups. Specifically, hsa_piR_019949 was downregulated in chondrocytes when stimulated by IL-1ß, an inflammatory molecule. In further investigations, we discovered that overexpression of hsa_piR_019949 in vitro led to increased proliferation and synthesis of the extracellular matrix in chondrocytes, which are cells responsible for cartilage formation. Conversely, suppressing hsa_piR_019949 expression resulted in increased apoptosis (cell death) and degradation of the extracellular matrix in chondrocytes. Additionally, we found that the NOD-like receptor signaling pathway is linked to the low expression of hsa_piR_019949 in a specific chondrocyte cell line called C28/I2. Furthermore, we observed that hsa_piR_019949 can inhibit the expression of a long non-coding RNA called NEAT1 in chondrocytes. We hypothesize that NEAT1 may serve as a downstream target gene regulated by hsa_piR_019949, potentially influencing chondrocyte metabolism and function in the context of osteoarthritis. CONCLUSIONS: PiRNA hsa_piR_019949 has shown potential in promoting the proliferation of chondrocytes and facilitating the synthesis of extracellular matrix in individuals with osteoarthritis. This is achieved by inhibiting the expression of a long non-coding RNA called NEAT1. The implication is that by using hsa_piR_019949 mimics, which are synthetic versions of the piRNA, as a therapeutic approach, it may be possible to effectively treat osteoarthritis.


Asunto(s)
Osteoartritis , ARN Largo no Codificante , Humanos , Condrocitos/metabolismo , ARN de Interacción con Piwi , ARN Largo no Codificante/metabolismo , Cartílago/metabolismo , Apoptosis/genética , Osteoartritis/genética , Osteoartritis/metabolismo
10.
Acta Neuropathol Commun ; 12(1): 7, 2024 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-38212848

RESUMEN

Mitosis is a critical criterion for meningioma grading. However, pathologists' assessment of mitoses is subject to significant inter-observer variation due to challenges in locating mitosis hotspots and accurately detecting mitotic figures. To address this issue, we leverage digital pathology and propose a computational strategy to enhance pathologists' mitosis assessment. The strategy has two components: (1) A depth-first search algorithm that quantifies the mathematically maximum mitotic count in 10 consecutive high-power fields, which can enhance the preciseness, especially in cases with borderline mitotic count. (2) Implementing a collaborative sphere to group a set of pathologists to detect mitoses under each high-power field, which can mitigate subjective random errors in mitosis detection originating from individual detection errors. By depth-first search algorithm (1) , we analyzed 19 meningioma slides and discovered that the proposed algorithm upgraded two borderline cases verified at consensus conferences. This improvement is attributed to the algorithm's ability to quantify the mitotic count more comprehensively compared to other conventional methods of counting mitoses. In implementing a collaborative sphere (2) , we evaluated the correctness of mitosis detection from grouped pathologists and/or pathology residents, where each member of the group annotated a set of 48 high-power field images for mitotic figures independently. We report that groups with sizes of three can achieve an average precision of 0.897 and sensitivity of 0.699 in mitosis detection, which is higher than an average pathologist in this study (precision: 0.750, sensitivity: 0.667). The proposed computational strategy can be integrated with artificial intelligence workflow, which envisions the future of achieving a rapid and robust mitosis assessment by interactive assisting algorithms that can ultimately benefit patient management.


Asunto(s)
Neoplasias Meníngeas , Meningioma , Humanos , Meningioma/patología , Índice Mitótico/métodos , Inteligencia Artificial , Mitosis , Neoplasias Meníngeas/patología
11.
Opt Express ; 31(25): 42400-42412, 2023 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-38087615

RESUMEN

Passive mode-locking based on saturable absorbers (SAs) is an effective way to generate ultrafast pulses, while the spatiotemporal mode-locking (STML) based on SAs are rarely studied. We construct an all-fiber laser with InP quantum dots (QDs) SA, and realize multi-mode Q-switching (MMQS) and STML. In addition, by adjusting the polarization controller (PC) in the laser cavity, we obtain two different single-pulse STML states. The narrowest pulse widths of the two states are 57 ps and 32 ps, respectively, and the pulse width can be tuned continuously with increasing the pump power. By decoupling the effects of the PC and the SA in our experiment, we find that the polarization plays a key role in the selection of transverse modes. The effect of independent polarization on spatiotemporal mode-locked pulses has not been investigated before. To further analyze and understand the experimental results, we numerically solve the nonlinear Schrodinger equation, and compare the numerical simulation with the experimental results. In addition to passively adjusting cavity loss, the InP QD SA can balance the large walk off between different transverse modes, due to the spatial and spectral filtering effects. Our work has important implications for the design and application of all-fiber STML lasers.

12.
Arthroscopy ; 2023 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-38056725

RESUMEN

PURPOSE: To propose a modified approach to measuring the femoro-epiphyseal acetabular roof (FEAR) index while still abiding by its definition and biomechanical basis, and to compare the intra- and interobserver reliabilities of the original and the modified FEAR index. To propose a classification for medial sourcil edges. METHODS: We retrospectively reviewed a consecutive series of patients treated with periacetabular osteotomy and/or hip arthroscopy at a single institute. Patients with unilateral or bilateral symptomatic borderline hip(s) were included. Hips with remarkable osteoarthritis, deformities, history of previous surgery, or without symptoms were excluded. A modified FEAR index was defined using a best-fit circle to determine the sourcil line and 2 ancillary lines connecting femoral head and sourcil edges to determine epiphyseal line. Lateral center-edge angle, Sharp angle, Tönnis angle on all hips, as well as FEAR index with original and modified approaches, were measured. Intra- and interobserver reliability were calculated as intraclass correlation coefficients (ICCs) for the FEAR index with both approaches and other alignments. A classification was proposed to categorize medial sourcil edges. ICCs for the 2 approaches across different sourcil groups also were calculated. RESULTS: After we reviewed 411 patients, 49 were finally included. Thirty-two patients (40 hips) were identified as having borderline dysplasia defined by a lateral center-edge angle of 18 to 25°. Intraobserver ICCs for the modified method were good to excellent for borderline hips; poor to excellent for developmental dysplasia of the hip; and moderate to excellent for normal hips. As for interobserver reliability, the modified approach outperformed original approach with moderate-to-good interobserver reliability (developmental dysplasia of the hip group, ICC = 0.650; borderline dysplasia group, ICC = 0.813; normal hip group, ICC = 0.709). The medial sourcil edge was classified to 3 groups upon its morphology. Type II (39.0%) and III (43.9%) sourcil were the dominant patterns. The sourcil classification had substantial intraobserver agreement (observer 4, kappa = 0.68; observer 1, kappa = 0.799) and moderate interobserver agreement (kappa = 0.465). The modified approach to FEAR index possessed greater interobserver reliability in all medial sourcil edge patterns. CONCLUSIONS: The modified FEAR index has better intra- and interobserver reliability compared with the original approach in all hip groups and sourcil groups. Type II and III sourcil types account for the majority, to which the modified approach is better. LEVEL OF EVIDENCE: Level II, development of diagnostic criteria (consecutive patients with consistently applied reference standard and blinding).

13.
Proc Natl Acad Sci U S A ; 120(51): e2314264120, 2023 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-38100418

RESUMEN

The separator with high Young's modulus can avoid the danger of large-sized dendrites, but regulating the chemical behavior of lithium (Li) at the separator/anode interface can effectively eliminate the dendrite issue. Herein, a polyimine aerogel (PIA) with accurate nitrogen (N) functional design is used as the functional separator in Li metal batteries to promote uniform Li nucleation and suppress the dendrite growth. Specifically, the imine (N1) and protonated tertiary amine (N2) sites in the molecular structure of the PIA are significantly different in electron cloud density (ECD) distribution. The N1 site with higher ECD and the N2 site with lower ECD tend to attract and repulse Li+ through electrostatic interactions, respectively. This synergy effect of the PIA separator accelerates the interfacial Li+ diffusion on the Li anode to sustain a uniform two-dimensional Li nucleation behavior. Meanwhile, the well-defined nanochannels of the PIA separator show high affinity to electrolyte and bring uniform Li+ flux for Li plating/stripping. Consequently, the dendrites are effectively suppressed by the PIA separator in routine carbonate electrolyte, and the Li metal batteries with the PIA separator exhibit high Coulombic efficiency and stable high-rate cycling. These findings demonstrate that the ingenious marriage of special chemical structure designs and hierarchical pores can enable the separator to affect the interfacial Li nucleation behavior.

14.
Nanomaterials (Basel) ; 13(24)2023 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-38133031

RESUMEN

Perovskites have been recognized as a class of promising materials for optoelectronic devices. We intentionally include excessive Cs+ cations in precursors in the synthesis of perovskite CsPbBr3 nanocrystals and investigate how the Cs+ cations influence the lattice strain in these perovskite nanocrystals. Upon light illumination, the lattice strain due to the addition of alkali metal Cs+ cations can be compensated by light-induced lattice expansion. When the Cs+ cation in precursors is about 10% excessive, the electron-phonon coupling strength can be reduced by about 70%, and the carrier cooling can be slowed down about 3.5 times in lead halide perovskite CsPbBr3 nanocrystals. This work reveals a new understanding of the role of Cs+ cations, which take the A-site in ABX3 perovskite and provide a new way to improve the performance of perovskites and their practical devices further.

15.
Genes Dis ; 10(5): 2064-2081, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37492704

RESUMEN

Small nucleolar RNAs (snoRNAs) play critical roles in various biological processes. The aberrant expression or depletion of snoRNAs is related to various diseases. In previous research, most of the snoRNAs were categorized as C/D box snoRNAs and H/ACA box snoRNAs, whose typical functions were thought of as regulation of 2'-O-ribose methylation and pseudouridylation of ribosome RNAs, respectively. However, in the past two decades, studies have revealed an increasing number of snoRNAs without specific targets or determined cell functions. These findings indicated that some potential roles of snoRNAs are still unknown. Numerous studies have indicated the correlation of snoRNAs with human diseases. SnoRNAs play various roles in abundant biological processes, and they have great potential in controlling human diseases. This new and rising field could benefit from investigations of the disease pathogenesis, biomarker identification, and the determination of novel therapeutic targets. This review summarized the reports on snoRNAs and the regulation of different diseases in recent years.

16.
Angew Chem Int Ed Engl ; 62(37): e202306489, 2023 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-37506278

RESUMEN

Mechanical bonds have been utilized as promising motifs to construct mechanically interlocked aerogels (MIAs) with mechanical adaptivity and multifunctionality. However, fabricating such aerogels with not only precise chemical structures but also dynamic features remains challenging. Herein, we present MIAs carrying dense [2]rotaxane units, which bestow both the stability and flexibility of the aerogel network. Owing to the stable chemical structure of a [2]rotaxane, MIAs possessing a precise and full-scale mechanically interlocked network could be fabricated with the aid of diverse solvents. In addition, the dynamic nature of the [2]rotaxane resulted in morphologies and mechanical performances of the MIAs that can be dramatically modulated under chemical stimuli. We hope that the structure-property relationship in MIAs will facilitate the development of mechanically interlocked materials and provide novel opportunities toward constructing smart materials with multifunctionalities.

17.
J Am Chem Soc ; 145(16): 9011-9020, 2023 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-37052468

RESUMEN

Polycatenanes are extremely attractive topological architectures on account of their high degrees of conformational freedom and multiple motion patterns of the mechanically interlocked macrocycles. However, exploitation of these peculiar structural and dynamic characteristics to develop robust catenane materials is still a challenging goal. Herein, we synthesize an oligo[2]catenane that showcases mechanically robust properties at both the microscopic and macroscopic scales. The key feature of the structural design is controlling the force-bearing points on the metal-coordinated core of the [2]catenane moiety that is able to maximize the energy dissipation of the oligo[2]catenane via dissociation of metal-coordination bonds and then activation of sequential intramolecular motions of circumrotation, translation, and elongation under an external force. As such, at the microscopic level, the single-molecule force spectroscopy measurement exhibits that the force to rupture dynamic bonds in the oligo[2]catenane reaches a record high of 588 ± 233 pN. At the macroscopic level, our oligo[2]catenane manifests itself as the toughest catenane material ever reported (15.2 vs 2.43 MJ/m3). These fundamental findings not only deepen the understanding of the structure-property relationship of poly[2]catenanes with a full set of dynamic features but also provide a guiding principle to fabricate high-performance mechanically interlocked catenane materials.

18.
Front Bioeng Biotechnol ; 11: 1071692, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36873374

RESUMEN

Reducing the incidence of bone defects caused by trauma and other primary diseases is an urgent task in modern society. In the present study, we developed a gadolinium-doped whitlockite/chitosan (Gd-WH/CS) scaffold and assessed its biocompatibility, osteoinductivity, and bone regeneration capacity for the treatment of calvarial defect in a Sprague-Dawley (SD) rat model. The Gd-WH/CS scaffolds possessed a macroporous structure, with a pore size ranging 200-300 µm, which facilitated the growth of bone precursor cells and tissues into scaffold. Results of cytological and histological biosafety experiments showed that both WH/CS and Gd-WH/CS scaffolds were non-cytotoxic to human adipose-derived stromal cells (hADSCs) and bone tissue, which demonstrated the excellent biocompatibility of Gd-WH/CS scaffolds. Results of western blotting and real-time PCR analysis provided a possible mechanism that Gd3+ ions in the Gd-WH/CS scaffolds promoted the osteogenic differentiation of hADSCs through the GSK3ß/ß-catenin signaling pathway and significantly upregulated the expression of osteogenic related genes (OCN, OSX and COL1A1). Finally, in animal experiments, SD rat cranial defects were effectively treated and repaired with Gd-WH/CS scaffolds due to its appropriate degradation rate and excellent osteogenic activity. This study suggests the potential utility of the Gd-WH/CS composite scaffolds in treating bone defect disease.

19.
ACS Appl Mater Interfaces ; 15(21): 25161-25172, 2023 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-35894294

RESUMEN

Network topologies, especially some high-order topologies, are able to furnish cross-linked polymer materials with enhanced properties without altering their chemical composition. However, the fabrication of such topologically intriguing architectures at the macromolecular level and in-depth insights into their structure-property relationship remain a significant challenge. Herein, we relied on synergistic covalent-and-supramolecular polymers (CSPs) as a platform to prepare a range of polymer networks with an interwoven topology. Specifically, through the sequential supramolecular self-assemblies, the covalent polymers (CPs) and metallosupramolecular polymers (MSPs) could be interwoven in our CSPs by [2]pseudorotaxane cross-links. As a result, the obtained CSPs possessed a topological network that could not only promote the synergistic effect between CPs and MSPs to afford mechanically robust yet dynamic materials but also vest polymers with some functions, as manifested by force-induced hierarchical dissociations of supramolecular interactions and superior thermomechanical stability compared to our previously reported CSP systems. Furthermore, our CSPs exhibited tunable mechanical performance toward multiple stimuli including K+ and PPh3, demonstrating abundant stimuli-responsive properties. We hope that these findings could provide novel opportunities toward achieving topological structures at the macromolecular level and also motivate further explorations of polymeric materials via the way of controlling their topological structures.

20.
J Clin Neurosci ; 107: 23-33, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36462413

RESUMEN

Recently, a relationship between traumatic subdural hygroma (SDG) and chronic subdural hematoma (CSDH) has been proposed. However, the role of traumatic SDG in development of CSDH has not been well characterized. This systematic review aimed to estimate the rate of evolution of traumatic SDG to CSDH, and to identify risk factors associated with traumatic SDG evolution to CSDH. We searched MEDLINE, EMBASE, and Cochrane Library databases from inception to May 26, 2021, using the combination of the terms "subdural hygroma" and "chronic subdural hematoma." Using a random-effects model, we calculated a pooled estimate of rate of evolution of traumatic SDG to CSDH. In addition, we conducted a systematic review of studies of risk factors for traumatic SDG evolution to CSDH. Nineteen studies with 1,335 patients met the inclusion criteria for meta-analysis. The pooled estimate of evolution rate was 25.0 % (95 % CI, 19.3 %-30.7 %; I2 = 85.6 %), with significant heterogeneity among studies (P < 0.01). Age ≥ 60 years was associated independently with traumatic SDG evolution to CSDH, after adjustment for study design using multivariate meta-regression. Risk factors associated with evolution of traumatic SDG to CSDH were radiological characteristics such as thicker SDG and higher SDG CT value. The rate of traumatic SDGs evolution to CSDH is approximately 25 %. Patients aged 60 or older with traumatic SDGs are at increased risk of CSDH development. Thicker SDG and higher SDG CT value, are commonly reported risk factors for traumatic SDG evolution to CSDH. However, higher quality studies are needed.


Asunto(s)
Hematoma Subdural Crónico , Linfangioma Quístico , Efusión Subdural , Humanos , Hematoma Subdural Crónico/diagnóstico por imagen , Hematoma Subdural Crónico/epidemiología , Hematoma Subdural Crónico/etiología , Linfangioma Quístico/complicaciones , Efusión Subdural/diagnóstico por imagen , Efusión Subdural/epidemiología , Efusión Subdural/etiología , Complicaciones Posoperatorias/etiología , Factores de Riesgo
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