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1.
J Asian Nat Prod Res ; : 1-7, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38949198

RESUMEN

One new canthinone glycoside (1), together with six known compounds (2-7) including three lignans (2-4), two coumarins (5-6) and one phenol (7) was isolated from the root barks of Ailanthus altissima. The structure of new compound 1 was established by the interpretation of UV, IR, MS and NMR data, while its absolute configuration was determined by acid hydrolysis and GIAO NMR calculations with DP4+ probability analysis. The inhibitory effects of all compounds on Nitric oxide (NO) production were investigated in lipopolysaccharide (LPS)-induced RAW 264.7 cells. Results showed that compounds 2 and 5 displayed NO production inhibitory activity with IC50 values of 30.1 and 15.3 µM, respectively.

2.
Adv Mater ; : e2405183, 2024 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-38973222

RESUMEN

Biological materials relying on hierarchically ordered architectures inspire the emergence of advanced composites with mutually exclusive mechanical properties, but the efficient topology optimization and large-scale manufacturing remain challenging. Herein, this work proposes a scalable bottom-up approach to fabricate a novel nacre-like cement-resin composite with gradient brick-and-mortar (BM) structure, and demonstrates a machine learning-assisted method to optimize the gradient structure. The fabricated gradient composite exhibits an extraordinary combination of high flexural strength, toughness, and impact resistance. Particularly, the toughness and impact resistance of such composite attractively surpass the cement counterparts by factors of approximately 700 and 600 times, and even outperform natural rocks, fiber-reinforced cement-based materials and even some alloys. The strengthening and toughening mechanisms are clarified as the regional-matrix densifying and crack-tip shielding effects caused by the gradient BM structure. The developed gradient composite not only endows a promising structural material for protective applications in harsh scenarios, but also paves a new way for biomimetic metamaterials designing.

4.
World Neurosurg ; 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38964458

RESUMEN

OBJECTIVE: We aimed to preliminarily explore the efficacy and safety of unilateral biportal endoscopy (UBE) for the treatment of epidural cement leaks. We report a patient who underwent epidural cement leakage removal and achieved endoscopic spinal decompression. METHODS: A 67-year-old female patient underwent biportal endoscopic paraspinal decompression following percutaneous vertebroplasty for an osteoporotic fracture that resulted in neurologic impairment due to epidural cement leakage. A transforaminal biportal endoscopic surgery was performed to remove the leaked cement, and the left L1 and bilateral L2 nerves were decompressed. RESULTS: The patient's postoperative clinical course was uneventful. CONCLUSIONS: A paraspinal approach that avoids a posterior approach reduces the need to remove stabilizing facet bone, is truly minimally invasive and does not involve an instrumented fusion, maybe a helpful addition in the minimally invasive spine surgeon's armamentarium.

5.
Sci Rep ; 14(1): 12784, 2024 06 04.
Artículo en Inglés | MEDLINE | ID: mdl-38834708

RESUMEN

The prevalence of thyroid dysfunction diseases (TDFDs) and osteoporosis (OP) is high. Previous studies have indicated a potential association between TDFDs and OP, yet the causal direction remains unclear. This study aimed to investigate the potential causal relationship between TDFDs and the risk of developing OP and related fractures. We obtained pooled data from genome-wide association studies (GWASs) conducted on TDFDs and OP in European populations and identified single-nucleotide polymorphisms (SNPs) with genome-wide significance levels associated with exposure to TDFDs as instrumental variables. Inverse variance weighted (IVW) was employed as the primary method for Mendelian randomization (MR) analysis, supplemented by MR‒Egger, weighted median, simple mode and weighted mode methods. Sensitivity analyses were conducted to evaluate the robustness of the findings. The IVW method demonstrated an increased risk of OP in patients with TDFDs, including hyperthyroidism and hypothyroidism (TDFDs: OR = 1.11; 95% CI 1.09, 1.13; hypothyroidism: OR = 1.14; 95% CI 1.10, 1.17; hyperthyroidism: OR = 1.09; 95% CI 1.06, 1.12). These findings were supported by supplementary analysis, which revealed a positive correlation between TDFDs and the risk of OP. Multiple sensitivity analyses confirmed the absence of horizontal pleiotropy in the study, thus indicating the robustness of our results. The causal relationship between TDFDs and increased risk of OP implies the need for early bone mineral density (BMD) screening and proactive prevention and treatment strategies for individuals with TDFDs.


Asunto(s)
Estudio de Asociación del Genoma Completo , Análisis de la Aleatorización Mendeliana , Osteoporosis , Polimorfismo de Nucleótido Simple , Humanos , Osteoporosis/genética , Enfermedades de la Tiroides/genética , Enfermedades de la Tiroides/epidemiología , Hipertiroidismo/genética , Hipertiroidismo/complicaciones , Factores de Riesgo , Hipotiroidismo/genética , Hipotiroidismo/epidemiología
6.
Comput Biol Med ; 178: 108690, 2024 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-38879931

RESUMEN

Prevalent Gene Regulatory Network (GRN) construction methods rely on generalized correlation analysis. However, in biological systems, regulation is essentially a causal relationship that cannot be adequately captured solely through correlation. Therefore, it is more reasonable to infer GRNs from a causal perspective. Existing causal discovery algorithms typically rely on Directed Acyclic Graphs (DAGs) to model causal relationships, but it often requires traversing the entire network, which result in computational demands skyrocketing as the number of nodes grows and make causal discovery algorithms only suitable for small networks with one or two hundred nodes or fewer. In this study, we propose the SLIVER (cauSaL dIscovery Via dimEnsionality Reduction) algorithm which integrates causal structural equation model and graph decomposition. SLIVER introduces a set of factor nodes, serving as abstractions of different functional modules to integrate the regulatory relationships between genes based on their respective functions or pathways, thus reducing the GRN to the product of two low-dimensional matrices. Subsequently, we employ the structural causal model (SCM) to learn the GRN within the gene node space, enforce the DAG constraint in the low-dimensional space, and guide each factor to aggregate various functions through cosine similarity. We evaluate the performance of the SLIVER algorithm on 12 real single cell transcriptomic datasets, and demonstrate it outperforms other 12 widely used methods both in GRN inference performance and computational resource usage. The analysis of the gene information integrated by factor nodes also demonstrate the biological explanation of factor nodes in GRNs. We apply it to scRNA-seq of Type 2 diabetes mellitus to capture the transcriptional regulatory structural changes of ß cells under high insulin demand.

7.
Clin Chim Acta ; 560: 119752, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38821337

RESUMEN

Long non-coding RNAs (lncRNAs) are RNA sequences exceeding 200 nucleotides in length that lack protein-coding capacity and participate in diverse biological processes in the human body, particularly exerting a pivotal role in disease surveillance, diagnosis, and progression. Taurine upregulated gene 1 (TUG1) is a versatile lncRNA, and recent studies have revealed that the aberrant expression or function of TUG1 is intricately linked to the pathogenesis of liver diseases. Consequently, we have summarized the current understanding of the mechanism of TUG1 in liver diseases such as liver fibrosis, fatty liver, cirrhosis, liver injury, hepatitis, and liver cancer. Moreover, mounting evidence suggests that interventions targeting TUG1 or its downstream pathways may hold therapeutic promise for liver diseases. This review elucidates the characteristics, mechanisms, and targets of TUG1 in liver diseases, offering a theoretical basis for the prevention, diagnosis, treatment, and prognostic biomarkers of liver diseases.


Asunto(s)
Hepatopatías , ARN Largo no Codificante , Humanos , ARN Largo no Codificante/genética , Hepatopatías/genética , Hepatopatías/diagnóstico , Hepatopatías/metabolismo
8.
Eur Spine J ; 33(6): 2430-2438, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38733399

RESUMEN

BACKGROUND: Sarcopenia (SP) and intervertebral disc degeneration (IVDD) have a higher incidence in the elderly population. Previous studies have indicated a potential association between SP and IVDD. The objective of this study is to elucidate the potential causal relationship between sarcopenia-related traits and IVDD through Two-sample Mendelian randomization (MR) analysis. METHODS: We utilized a genome-wide association study conducted on the European population to collect aggregated data on sarcopenia and IVDD. Inverse variance weighting was primarily employed, supplemented by MR Egger, weighted median, simple model, and weighted model methods. Additionally, sensitivity analysis was performed to assess the robustness of the findings. RESULTS: Appendicular lean mass is positively associated with "Other intervertebral disc disorders" (OIDD) and "Prolapsed or slipped disc" (POSD) (OIDD: p = 0.002, OR = 1.120; POSD: p < 0.001, OR = 1.003), while grip strength (GS) is positively associated with POSD (left: p = 0.004, OR = 1.008; right: p < 0.001, OR = 1.010). It is worth mentioning that walking pace has significant causal relationship with "Low back pain" (LBP), "Lower back pain or/and sciatica" (LBPOAS), "Sciatica with lumbago" (SWL) and OIDD (LBP: p < 0.001, OR = 0.204; LBPOAS: p < 0.001, OR = 0.278; SWL: p = 0.003, OR = 0.249; OIDD: p < 0.001, OR = 0.256). CONCLUSION: The present study revealed the causal relationship between SP-related traits and IVDD and recommended to prevent and treat sarcopenia as a means of preventing IVDD in clinic practice.


Asunto(s)
Estudio de Asociación del Genoma Completo , Degeneración del Disco Intervertebral , Análisis de la Aleatorización Mendeliana , Sarcopenia , Humanos , Degeneración del Disco Intervertebral/genética , Degeneración del Disco Intervertebral/epidemiología , Sarcopenia/genética , Sarcopenia/epidemiología , Fuerza de la Mano/fisiología , Masculino , Femenino
9.
Pharmacol Res ; 204: 107202, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38704110

RESUMEN

Plant-derived extracellular vesicles (PDEV) constitute nanoscale entities comprising lipids, proteins, nucleic acids and various components enveloped by the lipid bilayers of plant cells. These vesicles play a crucial role in facilitating substance and information transfer not only between plant cells but also across different species. Owing to its safety, stability, and the abundance of raw materials, this substance has found extensive utilization in recent years within research endeavors aimed at treating various diseases. This article provides an overview of the pathways and biological characteristics of PDEV, along with the prevalent methods employed for its isolation, purification, and storage. Furthermore, we comprehensively outline the therapeutic implications of diverse sources of PDEV in musculoskeletal system disorders. Additionally, we explore the utilization of PDEV as platforms for engineering drug carriers, aiming to delve deeper into the significance and potential contributions of PDEV in the realm of the musculoskeletal system.


Asunto(s)
Vesículas Extracelulares , Músculo Esquelético , Plantas , Animales , Humanos , Portadores de Fármacos/química , Vesículas Extracelulares/metabolismo , Músculo Esquelético/metabolismo , Plantas/metabolismo
10.
Nat Mater ; 23(7): 944-950, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38783106

RESUMEN

Thin-film materials with large electromechanical responses are fundamental enablers of next-generation micro-/nano-electromechanical applications. Conventional electromechanical materials (for example, ferroelectrics and relaxors), however, exhibit severely degraded responses when scaled down to submicrometre-thick films due to substrate constraints (clamping). This limitation is overcome, and substantial electromechanical responses in antiferroelectric thin films are achieved through an unconventional coupling of the field-induced antiferroelectric-to-ferroelectric phase transition and the substrate constraints. A detilting of the oxygen octahedra and lattice-volume expansion in all dimensions are observed commensurate with the phase transition using operando electron microscopy, such that the in-plane clamping further enhances the out-of-plane expansion, as rationalized using first-principles calculations. In turn, a non-traditional thickness scaling is realized wherein an electromechanical strain (1.7%) is produced from a model antiferroelectric PbZrO3 film that is just 100 nm thick. The high performance and understanding of the mechanism provide a promising pathway to develop high-performance micro-/nano-electromechanical systems.

11.
Mater Today Bio ; 26: 101081, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38741924

RESUMEN

The degeneration of intervertebral discs is strongly associated with the occurrence of pyroptosis in nucleus pulposus (NP) cells. This pyroptosis is characterized by abnormal metabolism of fatty acids in the degenerative pathological state, which is further exacerbated by the inflammatory microenvironment and degradation of the extracellular matrix. In order to address this issue, we have developed a fibrin hydrogel complex (FG@PEV). This intricate formulation amalgamates the beneficial attributes of platelet extravasation vesicles, contributing to tissue repair and regeneration. Furthermore, this complex showcases exceptional stability, gradual-release capabilities, and a high degree of biocompatibility. In order to substantiate the biological significance of FG@PEV in intervertebral disc degeneration (IVDD), we conducted a comprehensive investigation into its potential mechanism of action through the integration of RNA-seq sequencing and metabolomics analysis. Furthermore, these findings were subsequently validated through experimentation in both in vivo and in vitro models. The experimental results revealed that the FG@PEV intervention possesses the capability to reshape the inflammatory microenvironment within the disc. It also addresses the irregularities in fatty acid metabolism of nucleus pulposus cells, consequently hindering cellular pyroptosis and slowing down disc degeneration through the regulation of extracellular matrix synthesis and degradation. As a result, this injectable gel system represents a promising and innovative therapeutic approach for mitigating disc degeneration.

12.
Quant Imaging Med Surg ; 14(5): 3381-3392, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38720871

RESUMEN

Background: Accurate classification of breast nodules into benign and malignant types is critical for the successful treatment of breast cancer. Traditional methods rely on subjective interpretation, which can potentially lead to diagnostic errors. Artificial intelligence (AI)-based methods using the quantitative morphological analysis of ultrasound images have been explored for the automated and reliable classification of breast cancer. This study aimed to investigate the effectiveness of AI-based approaches for improving diagnostic accuracy and patient outcomes. Methods: In this study, a quantitative analysis approach was adopted, with a focus on five critical features for evaluation: degree of boundary regularity, clarity of boundaries, echo intensity, and uniformity of echoes. Furthermore, the classification results were assessed using five machine learning methods: logistic regression (LR), support vector machine (SVM), decision tree (DT), naive Bayes, and K-nearest neighbor (KNN). Based on these assessments, a multifeature combined prediction model was established. Results: We evaluated the performance of our classification model by quantifying various features of the ultrasound images and using the area under the receiver operating characteristic (ROC) curve (AUC). The moment of inertia achieved an AUC value of 0.793, while the variance and mean of breast nodule areas achieved AUC values of 0.725 and 0.772, respectively. The convexity and concavity achieved AUC values of 0.988 and 0.987, respectively. Additionally, we conducted a joint analysis of multiple features after normalization, achieving a recall value of 0.98, which surpasses most medical evaluation indexes on the market. To ensure experimental rigor, we conducted cross-validation experiments, which yielded no significant differences among the classifiers under 5-, 8-, and 10-fold cross-validation (P>0.05). Conclusions: The quantitative analysis can accurately differentiate between benign and malignant breast nodules.

13.
Nat Commun ; 15(1): 3828, 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38714653

RESUMEN

Stabilization of topological spin textures in layered magnets has the potential to drive the development of advanced low-dimensional spintronics devices. However, achieving reliable and flexible manipulation of the topological spin textures beyond skyrmion in a two-dimensional magnet system remains challenging. Here, we demonstrate the introduction of magnetic iron atoms between the van der Waals gap of a layered magnet, Fe3GaTe2, to modify local anisotropic magnetic interactions. Consequently, we present direct observations of the order-disorder skyrmion lattices transition. In addition, non-trivial topological solitons, such as skyrmioniums and skyrmion bags, are realized at room temperature. Our work highlights the influence of random spin control of non-trivial topological spin textures.

14.
BMC Musculoskelet Disord ; 25(1): 367, 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38730478

RESUMEN

BACKGROUND: The traditional surgical procedures for upper lumbar disc herniation (ULDH) usually lead to frequent complications. We aim to investigate the clinical efficacy of the unilateral biportal endoscopy (UBE) technique in treating upper lumbar disc herniation (ULDH). METHODS: From January 2020 to December 2021, the clinical data of 28 patients with ULDH treated with the UBE technique were collected and analyzed for surgery time under UBE, postsurgical drainage, postsurgical hospital stay, and complications. The clinical efficacy was evaluated according to the modified MacNab score, Oswestry disability index (ODI), and visual analogue scale (VAS) of low back pain and lower limb pain before the surgery; one week, one month, and three months after the surgery; and at the last follow-up. RESULTS: All patients underwent the UBE surgery successfully. The surgery time under UBE for non-fusion cases was 47.50 ± 11.84 min (monosegment) and 75.00 ± 20.66 min (two segments), while that for fusion cases was 77.50 ± 21.02 min. The postsurgical drainage for non-fusion cases was 25.00 ± 13.94 mL (monosegment) and 38.00 ± 11.83 mL (two segments), while that for fusion cases was 71.25 ± 31.72 mL. The postsurgical hospital stay was 8.28 ± 4.22 days. The follow-up time was 15.82 ± 4.54 months. The VAS score for each time period after the surgery was significantly lower (P < 0.05), while the ODI was significantly higher than that before the surgery (P < 0.05). According to the modified MacNab scoring standard, the ratio of excellent to good was 96.43% at the last follow-up. Two patients experienced transient numbness and pain in their lower limbs and no activity disorder after the surgery, and they recovered after conservative treatment. CONCLUSIONS: The clinical effect of UBE technique in treating ULDH was reliable. According to the needs of the disease, the interlaminar approach or paraspinal approach of the UBE technique was selected. This technique took into account the effect of treatment, achieved the purpose of minimal invasiveness, and did not require special instruments. Therefore, it has the potential for clinical application.


Asunto(s)
Endoscopía , Desplazamiento del Disco Intervertebral , Vértebras Lumbares , Humanos , Femenino , Masculino , Vértebras Lumbares/cirugía , Vértebras Lumbares/diagnóstico por imagen , Persona de Mediana Edad , Desplazamiento del Disco Intervertebral/cirugía , Desplazamiento del Disco Intervertebral/diagnóstico por imagen , Adulto , Endoscopía/métodos , Resultado del Tratamiento , Estudios Retrospectivos , Tempo Operativo , Dimensión del Dolor , Tiempo de Internación , Complicaciones Posoperatorias/etiología
15.
Acta Neurochir (Wien) ; 166(1): 231, 2024 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-38787501

RESUMEN

BACKGROUND: The technique of spinal decompression under endoscopy has been widely applied, but reports on endoscopic cervical fixation are rare. The unilateral biportal endoscopic (UBE) technique stands out for its lesser muscle intrusion and more flexible surgical approach. METHOD: We applied the UBE approach for cervical fixation and laminectomy. We achieved bilateral lateral mass screw fixation by making an auxiliary UBE portal combined with the Roy-Camille and Magerl techniques. CONCLUSIONS: Our successful implementation of cervical fixation using the UBE technique at the C3/4 level suggests its efficacy. This approach is a valuable and minimally invasive option for cervical fixation.


Asunto(s)
Vértebras Cervicales , Endoscopía , Humanos , Vértebras Cervicales/cirugía , Vértebras Cervicales/diagnóstico por imagen , Endoscopía/métodos , Endoscopía/instrumentación , Tornillos Óseos , Descompresión Quirúrgica/métodos , Descompresión Quirúrgica/instrumentación , Laminectomía/métodos , Laminectomía/instrumentación , Masculino , Persona de Mediana Edad , Femenino
16.
Nat Mater ; 23(7): 898-904, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38622325

RESUMEN

A magnon is a collective excitation of the spin structure in a magnetic insulator and can transmit spin angular momentum with negligible dissipation. This quantum of a spin wave has always been manipulated through magnetic dipoles (that is, by breaking time-reversal symmetry). Here we report the experimental observation of chiral spin transport in multiferroic BiFeO3 and its control by reversing the ferroelectric polarization (that is, by breaking spatial inversion symmetry). The ferroelectrically controlled magnons show up to 18% modulation at room temperature. The spin torque that the magnons in BiFeO3 carry can be used to efficiently switch the magnetization of adjacent magnets, with a spin-torque efficiency comparable to the spin Hall effect in heavy metals. Utilizing such controllable magnon generation and transmission in BiFeO3, an all-oxide, energy-scalable logic is demonstrated composed of spin-orbit injection, detection and magnetoelectric control. Our observations open a new chapter of multiferroic magnons and pave another path towards low-dissipation nanoelectronics.

17.
J Orthop Translat ; 45: 211-225, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38586591

RESUMEN

Background: Osteoarthritis (OA) is a degenerative joint disease characterized by the breakdown of joint cartilage and underlying bone. Macrophages are a type of white blood cell that plays a critical role in the immune system and can be found in various tissues, including joints. Research on the relationship between OA and macrophages is essential to understand the mechanisms underlying the development and progression of OA. Objective: This study was performed to analyze the functions of the IRF1-GCN5-SETD2-SMARCC1 axis in osteoarthritis (OA) development. Methods: A single-cell RNA sequencing (scRNA-seq) dataset, was subjected to a comprehensive analysis aiming to identify potential regulators implicated in the progression of osteoarthritis (OA). In order to investigate the role of IRF1 and SMARCC1, knockdown experiments were conducted in both OA-induced rats and interleukin (IL)-1ß-stimulated chondrocytes, followed by the assessment of OA-like symptoms, secretion of inflammatory cytokines, and polarization of macrophages. Furthermore, the study delved into the identification of aberrant epigenetic modifications and functional enzymes responsible for the regulation of SMARCC1 by IRF1. To evaluate the clinical significance of the factors under scrutiny, a cohort comprising 13 patients diagnosed with OA and 7 fracture patients without OA was included in the analysis. Results: IRF1 was found to exert regulatory control over the expression of SMARCC1, thus playing a significant role in the development of osteoarthritis (OA). The knockdown of either IRF1 or SMARCC1 disrupted the pro-inflammatory effects induced by IL-1ß in chondrocytes, leading to a mitigation of OA-like symptoms, including inflammatory infiltration, cartilage degradation, and tissue injury, in rat models. Additionally, this intervention resulted in a reduction in the predominance of M1 macrophages both in vitro and in vivo. Significant epigenetic modifications, such as abundant H3K27ac and H3K4me3 marks, were observed near the SMARCC1 promoter and 10 kb upstream region. These modifications were attributed to the recruitment of GCN5 and SETD2, which are functional enzymes responsible for these modifications. Remarkably, the overexpression of either GCN5 or SETD2 restored SMARCC1 expression in rat cartilages or chondrocytes, consequently exacerbating the OA-like symptoms. Conclusion: This research postulates that the transcriptional activity of SMARCC1 can be influenced by IRF1 through the recruitment of GCN5 and SETD2, consequently regulating the H3K27ac and H3K4me3 modifications in close proximity to the SMARCC1 promoter and 10 kb upstream region. These modifications, in turn, facilitate the M1 skewing of macrophages and contribute to the progression of osteoarthritis (OA). The Translational Potential of this Article: The study demonstrated that the regulation of SMARCC1 by IRF1 plays a crucial role in the development of OA. Knocking down either IRF1 or SMARCC1 disrupted the pro-inflammatory effects induced by IL-1ß in chondrocytes, leading to a mitigation of OA-like symptoms in rat models. These symptoms included inflammatory infiltration, cartilage degradation, and tissue injury. These findings suggest that targeting the IRF1-SMARCC1 regulatory axis, as well as the associated epigenetic modifications, could potentially be a novel approach in the development of OA therapies, offering new opportunities for disease management and improved patient outcomes.

18.
Science ; 384(6692): 185-189, 2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-38603510

RESUMEN

Ultrahigh-power-density multilayer ceramic capacitors (MLCCs) are critical components in electrical and electronic systems. However, the realization of a high energy density combined with a high efficiency is a major challenge for practical applications. We propose a high-entropy design in barium titanate (BaTiO3)-based lead-free MLCCs with polymorphic relaxor phase. This strategy effectively minimizes hysteresis loss by lowering the domain-switching barriers and enhances the breakdown strength by the high atomic disorder with lattice distortion and grain refining. Benefiting from the synergistic effects, we achieved a high energy density of 20.8 joules per cubic centimeter with an ultrahigh efficiency of 97.5% in the MLCCs. This approach should be universally applicable to designing high-performance dielectrics for energy storage and other related functionalities.

19.
Clin Transl Sci ; 17(4): e13762, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38591811

RESUMEN

Mibavademab (previously known as REGN4461), a fully human monoclonal antibody, is being investigated for the treatment of conditions associated with leptin deficiency. Here, we report pharmacokinetics (PKs), pharmacodynamics, and immunogenicity from a phase I study in healthy participants (NCT03530514). In part A, lean or overweight healthy participants were randomized to single-ascending-dose cohorts of 0.3, 1.0, 3.0, 10, and 30 mg/kg intravenous (i.v.), or 300 and 600 mg subcutaneous doses of mibavademab or placebo. In part B, overweight or obese participants were randomized to receive multiple doses of mibavademab (15 mg/kg i.v. loading dose and 10 mg/kg i.v. at weeks 3, 6, and 9) or placebo, stratified by body mass index and baseline leptin levels: low leptin (<5 ng/mL) or relatively low leptin (5-8 ng/mL in men and 5-24 ng/mL in women). Fifty-six and 55 participants completed the single-ascending-dose and multiple-dose parts, respectively. In the single-ascending-dose cohorts, mibavademab PKs were nonlinear with target-mediated elimination, greater than dose-proportional increases in exposure, and there were no dose-dependent differences in total soluble leptin receptor (sLEPR) levels in serum over time. Following multiple-dose administration of mibavademab in participants with leptin <8 ng/mL, lower mean mibavademab concentrations, higher mean total sLEPR concentrations, and larger mean decreases in body weight than in the relatively low leptin cohorts were observed. Baseline leptin was correlated with mibavademab PKs and pharmacodynamics. No treatment-emergent anti-mibavademab antibodies were observed in any mibavademab-treated participant. Results from this study collectively inform further development of mibavademab to treat conditions associated with leptin deficiency.


Asunto(s)
Leptina , Sobrepeso , Masculino , Humanos , Femenino , Leptina/farmacocinética , Leptina/uso terapéutico , Receptores de Leptina/uso terapéutico , Obesidad/tratamiento farmacológico , Índice de Masa Corporal , Método Doble Ciego
20.
Nanoscale ; 16(17): 8573-8582, 2024 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-38602025

RESUMEN

Advanced nanotechniques and the corresponding complex nanostructures they produce represent some of the most powerful tools for developing novel drug delivery systems (DDSs). In this study, a side-by-side electrospraying process was developed for creating double-chamber nanoparticles in which Janus soluble polyvinylpyrrolidone (PVP) patches were added to the sides of Eudragit RL100 (RL100) particles. Both sides were loaded with the poorly water-soluble drug paracetamol (PAR). Scanning electron microscope results demonstrated that the electrosprayed nanoparticles had an integrated Janus nanostructure. Combined with observations of the working processes, the microformation mechanism for creating the Janus PVP patches was proposed. XRD, DSC, and ATR-FTIR experiments verified that the PAR drug was present in the Janus particles in an amorphous state due to its fine compatibility with the polymeric matrices. In vitro dissolution tests verified that the Janus nanoparticles were able to provide a typical biphasic drug release profile, with the PVP patches providing 43.8 ± 5.4% drug release in the first phase in a pulsatile manner. In vivo animal experiments indicated that the Janus particles, on one hand, could provide a faster therapeutic effect than the electrosprayed sustained-release RL100 nanoparticles. On the other hand, they could maintain a therapeutic blood drug concentration for a longer period. The controlled release mechanism of the drug was proposed. The protocols reported here pioneer a new process-structure-performance relationship for developing Janus-structure-based advanced nano-DDSs.


Asunto(s)
Acetaminofén , Nanopartículas , Povidona , Acetaminofén/química , Acetaminofén/farmacocinética , Acetaminofén/administración & dosificación , Povidona/química , Animales , Nanopartículas/química , Liberación de Fármacos , Portadores de Fármacos/química , Resinas Acrílicas/química , Masculino
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