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1.
Ultrasound Med Biol ; 2024 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-38972792

RESUMEN

OBJECTIVE: Bone diseases deteriorate the microstructure of bone tissue. Optical-resolution photoacoustic microscopy (OR-PAM) enables high spatial resolution of imaging bone tissues. However, the spatiotemporal trade-off limits the application of OR-PAM. The purpose of this study was to improve the quality of OR-PAM images without sacrificing temporal resolution. METHODS: In this study, we proposed the Photoacoustic Dense Attention U-Net (PADA U-Net) model, which was used for reconstructing full-scanning images from under-sampled images. Thereby, this approach breaks the trade-off between imaging speed and spatial resolution. RESULTS: The proposed method was validated on resolution test targets and bovine cancellous bone samples to demonstrate the capability of PADA U-Net in recovering full-scanning images from under-sampled OR-PAM images. With a down-sampling ratio of [4, 1], compared to bilinear interpolation, the Peak Signal-to-Noise Ratio and Structural Similarity Index Measure values (averaged over the test set of bovine cancellous bone) of the PADA U-Net were improved by 2.325 dB and 0.117, respectively. CONCLUSION: The results demonstrate that the PADA U-Net model reconstructed the OR-PAM images well with different levels of sparsity. Our proposed method can further facilitate early diagnosis and treatment of bone diseases using OR-PAM.

2.
Ultrasound Med Biol ; 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-39013725

RESUMEN

OBJECTIVE: Photoacoustic imaging (PAI) is a promising transcranial imaging technique. However, the distortion of photoacoustic signals induced by the skull significantly influences its imaging quality. We aimed to use deep learning for removing artifacts in PAI. METHODS: In this study, we propose a polarized self-attention dense U-Net, termed PSAD-UNet, to correct the distortion and accurately recover imaged objects beneath bone plates. To evaluate the performance of the proposed method, a series of experiments was performed using a custom-built PAI system. RESULTS: The experimental results showed that the proposed PSAD-UNet method could effectively implement transcranial PAI through a one- or two-layer bone plate. Compared with the conventional delay-and-sum and classical U-Net methods, PSAD-UNet can diminish the influence of bone plates and provide high-quality PAI results in terms of structural similarity and peak signal-to-noise ratio. The 3-D experimental results further confirm the feasibility of PSAD-UNet in 3-D transcranial imaging. CONCLUSION: PSAD-UNet paves the way for implementing transcranial PAI with high imaging accuracy, which reveals broad application prospects in preclinical and clinical fields.

3.
Medicine (Baltimore) ; 103(23): e38520, 2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38847663

RESUMEN

BACKGROUND: To elucidate the differences in mechanical performance between a novel axially controlled compression spinal rod (ACCSR) for lumbar spondylolysis (LS) and the common spinal rod (CSR). METHODS: A total of 36 ACCSRs and 36 CSRs from the same batch were used in this study, each with a diameter of 6.0 mm. Biomechanical tests were carried out on spinal rods for the ACCSR group and on pedicle screw-rod internal fixation systems for the CSR group. The spinal rod tests were conducted following the guidelines outlined in the American Society for Testing and Materials (ASTM) F 2193, while the pedicle screw-rod internal fixation system tests adhered to ASTM F 1798-97 standards. RESULTS: The stiffness of ACCSR and CSR was 1559.15 ±â€…50.15 and 3788.86 ±â€…156.45 N/mm (P < .001). ACCSR's yield load was 1345.73 (1297.90-1359.97) N, whereas CSR's was 4046.83 (3805.8-4072.53) N (P = .002). ACCSR's load in the 2.5 millionth cycle of the fatigue four-point bending test was 320 N. The axial gripping capacity of ACCSR and CSR was 1632.53 ±â€…165.64 and 1273.62 ±â€…205.63 N (P = .004). ACCSR's torsional gripping capacity was 3.45 (3.23-3.47) Nm, while CSR's was 3.27 (3.07-3.59) Nm (P = .654). The stiffness of the pedicle screws of the ACCSR and CSR group was 783.83 (775.67-798.94) and 773.14 (758.70-783.62) N/mm (P = .085). The yield loads on the pedicle screws of the ACCSR and CSR group was 1345.73 (1297.90-1359.97) and 4046.83 (3805.8-4072.53) N (P = .099). CONCLUSION: Although ACCSR exhibited lower yield load, stiffness, and fatigue resistance compared to CSR, it demonstrated significantly higher axial gripping capacity and met the stress requirement of the human isthmus. Consequently, ACCSR presents a promising alternative to CSR for LS remediation.


Asunto(s)
Vértebras Lumbares , Ensayo de Materiales , Tornillos Pediculares , Espondilólisis , Vértebras Lumbares/cirugía , Humanos , Fenómenos Biomecánicos , Espondilólisis/cirugía , Espondilólisis/fisiopatología , Fijadores Internos , Pruebas Mecánicas
4.
J Control Release ; 371: 313-323, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38823585

RESUMEN

Poly(ethylene glycol) (PEG) is widely utilized as a hydrophilic coating to extend the circulation time and improve the tumor accumulation of polymeric micelles. Nonetheless, PEGylated micelles often activate complement proteins, leading to accelerated blood clearance and negatively impacting drug efficacy and safety. Here, we have crafted amphiphilic block copolymers that merge hydrophilic sulfoxide-containing polymers (psulfoxides) with the hydrophobic drug 7-ethyl-10-hydroxylcamptothecin (SN38) into drug-conjugate micelles. Our findings show that the specific variant, PMSEA-PSN38 micelles, remarkably reduce protein fouling, prolong blood circulation, and improve intratumoral accumulation, culminating in significantly increased anti-cancer efficacy compared with PEG-PSN38 counterpart. Additionally, PMSEA-PSN38 micelles effectively inhibit complement activation, mitigate leukocyte uptake, and attenuate hyperactivation of inflammatory cells, diminishing their ability to stimulate tumor metastasis and cause inflammation. As a result, PMSEA-PSN38 micelles show exceptional promise in the realm of anti-metastasis and significantly abate SN38-induced intestinal toxicity. This study underscores the promising role of psulfoxides as viable PEG substitutes in the design of polymeric micelles for efficacious anti-cancer drug delivery.


Asunto(s)
Irinotecán , Micelas , Profármacos , Animales , Profármacos/administración & dosificación , Profármacos/química , Profármacos/farmacología , Humanos , Irinotecán/administración & dosificación , Irinotecán/farmacocinética , Línea Celular Tumoral , Antineoplásicos/administración & dosificación , Antineoplásicos/química , Antineoplásicos/farmacología , Antineoplásicos/farmacocinética , Polímeros/química , Femenino , Ratones Endogámicos BALB C , Polietilenglicoles/química , Sulfóxidos , Ratones , Intestinos/efectos de los fármacos , Ratones Desnudos , Neoplasias/tratamiento farmacológico , Neoplasias/patología , Portadores de Fármacos/química
5.
Protein Cell ; 2024 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-38801297

RESUMEN

Cytokinesis is required for faithful division of cytoplasmic components and duplicated nuclei into two daughter cells. Midbody, a protein-dense organelle that forms at the intercellular bridge, is indispensable for successful cytokinesis. However, the regulatory mechanism of cytokinesis at the midbody still remains elusive. Here, we unveil a critical role for NudC-like protein 2 (NudCL2), a co-chaperone of heat shock protein 90 (Hsp90), in cytokinesis regulation by stabilizing regulator of chromosome condensation 2 (RCC2) at the midbody in mammalian cells. NudCL2 localizes at the midbody, and its downregulation results in cytokinesis failure, multinucleation and midbody disorganization. Using iTRAQ-based quantitative proteomic analysis, we find that RCC2 levels are decreased in NudCL2 knockout (KO) cells. Moreover, Hsp90 forms a complex with NudCL2 to stabilize RCC2, which is essential for cytokinesis. RCC2 depletion mirrors phenotypes observed in NudCL2-downregulated cells. Importantly, ectopic expression of RCC2 rescues the cytokinesis defects induced by NudCL2 deletion, but not vice versa. Together, our data reveal the significance of the NudCL2/Hsp90/RCC2 pathway in cytokinesis at the midbody.

6.
Adv Mater ; : e2400894, 2024 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-38636448

RESUMEN

Peritoneal metastasis (PM) is considered one of the most dreaded forms of cancer metastases for both patients and physicians. Aggressive cytoreductive surgery (CRS) is the primary treatment for peritoneal metastasis. Unfortunately, this intensive treatment frequently causes clinical complications, such as postoperative recurrence, metastasis, and adhesion formation. Emerging evidence suggests that neutrophil extracellular traps (NETs) released by inflammatory neutrophils contribute to these complications. Effective NET-targeting strategies thus show considerable potential in counteracting these complications but remain challenging. Here, one type of sulfoxide-containing homopolymer, PMeSEA, with potent fouling-resistant and NET-inhibiting capabilities, is synthesized and screened. Hydrating sulfoxide groups endow PMeSEA with superior nonfouling ability, significantly inhibiting protein/cell adhesion. Besides, the polysulfoxides can be selectively oxidized by ClO- which is required to stabilize the NETs rather than H2O2, and ClO- scavenging effectively inhibits NETs formation without disturbing redox homeostasis in tumor cells and quiescent neutrophils. As a result, PMeSEA potently prevents postoperative adhesions, significantly suppresses peritoneal metastasis, and shows synergetic antitumor activity with chemotherapeutic 5-Fluorouracil. Moreover, coupling CRS with PMeSEA potently inhibits CRS-induced tumor metastatic relapse and postoperative adhesions. Notably, PMeSEA exhibits low in vivo acute and subacute toxicities, implying significant potential for clinical postoperative adjuvant treatment.

7.
J Nanobiotechnology ; 22(1): 177, 2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-38609995

RESUMEN

The current first-line treatment for repairing cartilage defects in clinical practice is the creation of microfractures (MF) to stimulate the release of mesenchymal stem cells (MSCs); however, this method has many limitations. Recent studies have found that MSC-derived extracellular vesicles (MSC-EVs) play an important role in tissue regeneration. This study aimed to verify whether MSC-EVs promote cartilage damage repair mediated by MFs and to explore the repair mechanisms. In vitro experiments showed that human umbilical cord Wharton's jelly MSC-EVs (hWJMSC-EVs) promoted the vitality of chondrocytes and the proliferation and differentiation ability of bone marrow-derived MSCs. This was mainly because hWJMSC-EVs carry integrin beta-1 (ITGB1), and cartilage and bone marrow-derived MSCs overexpress ITGB1 after absorbing EVs, thereby activating the transforming growth factor-ß/Smad2/3 axis. In a rabbit knee joint model of osteochondral defect repair, the injection of different concentrations of hWJMSC-EVs into the joint cavity showed that a concentration of 50 µg/ml significantly improved the formation of transparent cartilage after MF surgery. Extraction of regenerated cartilage revealed that the changes in ITGB1, transforming growth factor-ß, and Smad2/3 were directly proportional to the repair of regenerated cartilage. In summary, this study showed that hWJMSC-EVs promoted cartilage repair after MF surgery.


Asunto(s)
Fracturas por Estrés , Humanos , Animales , Conejos , Cartílago , Condrocitos , Factor de Crecimiento Transformador beta , Factores de Crecimiento Transformadores
8.
Opt Lett ; 49(8): 1949-1952, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38621048

RESUMEN

Methods have been proposed in recent years aimed at pushing photoacoustic imaging resolution beyond the acoustic diffraction limit, among which those based on random speckle illumination show particular promise. In this Letter, we propose a data-driven deep learning approach to processing the added spatiotemporal information resulting from speckle illumination, where the neural network learns the distribution of absorbers from a series of different samplings of the imaged area. In ex-vivo experiments based on the tomography configuration with prominent artifacts, our method successfully breaks the acoustic diffraction limit and delivers better results in identifying individual targets when compared against a selection of other leading methods.

9.
J Cell Biol ; 223(6)2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38526325

RESUMEN

N6, 2'-O-dimethyladenosine (m6Am) is a widespread RNA modification catalyzed by the methyltransferase PCIF1 (phosphorylated CTD interacting factor 1). Despite its prevalence, the biological functions of m6Am in RNA remain largely elusive. Here, we report a critical role of PCIF1-dependent m6Am RNA modification in ciliogenesis in RPE-1 cells. Our findings demonstrate that PCIF1 acts as a negative regulator of ciliation through its m6Am methyltransferase activity. A quantitative proteomic analysis identifies BICD2 as a downstream target of PCIF1, with PCIF1 depletion resulting in a significant increase in BICD2 levels. BICD2 depletion leads to a significant reduction in ciliation. Crucially, the ciliary phenotype in PCIF1-depleted cells is reversed upon BICD2 knockdown. Further investigations reveal that PCIF1 regulates BICD2 protein levels through its m6Am catalytic activity, which reduces the stability and translation efficiency of BICD2 mRNA. Single-base resolution LC-MS analysis identifies the m6Am site on BICD2 mRNA modified by PCIF1. These findings establish the essential involvement of PCIF1-dependent m6Am modification in ciliogenesis.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales , Cromatografía Líquida con Espectrometría de Masas , Proteínas Asociadas a Microtúbulos , Proteínas Nucleares , Proteómica , Metiltransferasas/genética , ARN , ARN Mensajero/genética , Humanos , Línea Celular , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Proteínas Nucleares/metabolismo , Proteínas Asociadas a Microtúbulos/metabolismo
10.
J Mol Cell Biol ; 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38509021

RESUMEN

N 6,2'-O-dimethyladenosine (m6Am) is a prevalent modification frequently found at the 5' cap-adjacent adenosine of mRNAs and snRNAs and the internal adenosine of snRNAs. This dynamic and reversible modification is under the regulation of methyltransferases PCIF1 and METTL4, along with the demethylase FTO. m6Am RNA modification plays a crucial role in the regulation of pre-mRNA splicing, mRNA stability, and translation, thereby influencing gene expression. In recent years, there has been growing interest in exploring the functions of m6Am and its relevance to human diseases. In this review, we provide a comprehensive overview of the current knowledge concerning m6Am, with a focus on m6Am-modifying enzymes, sequencing approaches for its detection, and its impacts on pre-mRNA splicing, mRNA stability, and translation regulation. Furthermore, we highlight the roles of m6Am in the context of obesity, viral infections, and cancers, unravelling its underlying regulatory mechanisms.

11.
J Proteome Res ; 2024 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-38315831

RESUMEN

The extracellular matrix (ECM) is a complex assembly of proteins that provide interstitial scaffolding and elastic recoil for human lungs. The pulmonary extracellular matrix is increasingly recognized as an independent bioactive entity, by creating biochemical and mechanical signals that influence disease pathogenesis, making it an attractive therapeutic target. However, the pulmonary ECM proteome ("matrisome") remains challenging to analyze by mass spectrometry due to its inherent biophysical properties and relatively low abundance. Here, we introduce a strategy designed for rapid and efficient characterization of the human pulmonary ECM using the photocleavable surfactant Azo. We coupled this approach with trapped ion mobility MS with diaPASEF to maximize the depth of matrisome coverage. Using this strategy, we identify nearly 400 unique matrisome proteins with excellent reproducibility that are known to be important in lung biology, including key core matrisome proteins.

12.
bioRxiv ; 2024 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-38405927

RESUMEN

BACKGROUND: The adult human heart following a large myocardial infarction is unable to regenerate heart muscle and instead forms scar with the risk of progressive heart failure. Large animal studies have shown that intramyocardial injection of human pluripotent stem cell-derived cardiomyocytes (hPSC-CMs) following a myocardial infarction result in cell grafts but also ventricular arrhythmias. We hypothesized that intramyocardial injection of committed cardiac progenitor cells (CCPs) derived from iPSCs, combined with cardiac fibroblast-derived extracellular matrix (cECM) to enhance cell retention will: i) form cardiomyocyte containing functional grafts, ii) be free of ventricular arrhythmias and iii) restore left ventricular contractility in a post-myocardial infarction (MI) cardiomyopathy swine model. METHODS: hiPSCs were differentiated using bioreactors and small molecules to produce a population of committed cardiac progenitor cells (CCPs). MI was created using a coronary artery balloon occlusion and reperfusion model in Yucatan mini pigs. Four weeks later, epicardial needle injections of CCPs+cECM were performed in a small initial feasibility cohort, and then transendocardial injections (TEI) of CCPs+cECM, CCPs alone, cECM alone or vehicle control into the peri-infarct region in a larger randomized cohort. A 4-drug immunosuppression regimen was administered to prevent rejection of human CCPs. Arrhythmias were evaluated using implanted event recorders. Magnetic resonance imaging (MRI) and invasive pressure volume assessment were used to evaluate left ventricular anatomic and functional performance, including viability. Detailed histology was performed on the heart to detect human grafts. RESULTS: A scalable biomanufacturing protocol was developed generating CCPs which can efficiently differentiate to cardiomyocytes or endothelial cells in vitro. Intramyocardial delivery of CCPs to post-MI porcine hearts resulted in engraftment and differentiation of CCPs to form ventricular cardiomyocyte rich grafts. There was no significant difference in cardiac MRI-based measured cardiac volumes or function between control, CCP and CCP+cECM groups; however, dobutamine stimulated functional reserve was improved in CCP and CCP+cECM groups. TEI delivery of CCPs with or without cECM did not result in tumors or trigger ventricular arrhythmias. CONCLUSIONS: CCPs are a promising cell source for post-MI heart repair using clinically relevant TEI with a low risk of engraftment ventricular arrhythmias.

13.
FASEB J ; 38(2): e23406, 2024 01 31.
Artículo en Inglés | MEDLINE | ID: mdl-38193601

RESUMEN

Cancer-associated fibroblast (CAF) has emerged as a key contributor to the remodeling of tumor microenvironment through the expression and secretion of extracellular matrix (ECM) proteins, thereby promoting carcinogenesis. However, the precise contribution of ECM proteins from CAFs to gastric carcinogenesis remains poorly understood. In this study, we find that matrilin-3 (MATN3), an upregulated ECM protein associated with poorer prognosis in gastric cancer patients, originates from CAFs in gastric cancer tissues. Ectopic expression of MATN3 in CAFs significantly promotes the invasion of gastric cancer cells, which can be attenuated by neutralizing MATN3 with its antibody. Notably, a portion of MATN3 protein is found to form puncta in gastric cancer tissues ECM. MATN3 undergoes phase separation, which is mediated by its low complexity (LC) and coiled-coil (CC) domains. Moreover, overexpression of MATN3 deleted with either LC or CC in CAFs is unable to promote the invasion of gastric cancer cells, suggesting that LC or CC domain is required for the effect of CAF-secreted MATN3 in gastric cancer cell invasion. Additionally, orthotopic co-injection of gastric cancer cells and CAFs expressing MATN3, but not its ΔLC and ΔCC mutants, leads to enhanced gastric cancer cell invasion in mouse models. Collectively, our works suggest that MATN3 is secreted by CAFs and undergoes phase separation, which promotes gastric cancer invasion.


Asunto(s)
Fibroblastos Asociados al Cáncer , Proteínas Matrilinas , Neoplasias Gástricas , Animales , Humanos , Ratones , Carcinogénesis , Proteínas Matrilinas/genética , Invasividad Neoplásica , Separación de Fases , Neoplasias Gástricas/genética , Microambiente Tumoral
14.
Cytotherapy ; 26(1): 81-87, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37930292

RESUMEN

Cardiac fibroblasts (CFs) are critical components of the cardiac niche and primarily responsible for assembly and maintenance of the cardiac extracellular matrix (ECM). CFs are increasingly of interest for tissue engineering and drug development applications, as they provide synergistic support to cardiomyocytes through direct cell-to-cell signaling and cell-to-ECM interactions via soluble factors, including cytokines, growth factors and extracellular vesicles. CFs can be activated to a cardiac myofibroblast (CMF) phenotype upon injury or stimulation with transforming growth factor beta 1. Once activated, CMFs assemble collagen-rich ECM, which is vitally important to stabilize scar formation following myocardial infarction, for example. Although there is greater experience with culture expansion of CFs among non-human strains, very little is known about human CF-to-CMF transitions and expression patterns during culture expansion. In this study, we evaluated for shifts in inflammatory and angiogenic expression profiles of human CFs in typical culture expansion conditions. Understanding shifts in cellular expression patterns during CF culture expansion is critically important to establish quality benchmarks and optimize large-scale manufacturing for future clinical applications.


Asunto(s)
Miocardio , Miofibroblastos , Humanos , Miofibroblastos/metabolismo , Secretoma , Fibroblastos , Fenotipo , Expresión Génica
15.
J Control Release ; 366: 128-141, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38104775

RESUMEN

Tumor-associated macrophages play pivotal roles in tumor progression and metastasis. Macrophage-mediated clearance of apoptotic cells (efferocytosis) supports inflammation resolution, contributing to immune evasion in colorectal cancers. To reverse this immunosuppressive process, we propose a readily translatable RNA therapy to selectively inhibit macrophage-mediated efferocytosis in tumor microenvironment. A clinically approved lipid nanoparticle platform (LNP) is employed to encapsulate siRNA for the phagocytic receptor MerTK (siMerTK), enabling selective MerTK inhibition in the diseased organ. Decreased MerTK expression in tumor-associated macrophages results in apoptotic cell accumulation and immune activation in tumor microenvironment, leading to suppressed tumor growth and better survival in both liver and peritoneal metastasis models of colorectal cancers. siMerTK delivery combined with PD-1 blockade further produces enhanced antimetastatic efficacy with reactivated intratumoral immune milieu. Collectively, LNP-based siMerTK delivery combined with immune checkpoint therapy may present a feasible modality for metastatic colorectal cancer therapy.


Asunto(s)
Neoplasias del Colon , Eferocitosis , Humanos , Tirosina Quinasa c-Mer , Macrófagos , ARN Interferente Pequeño , Microambiente Tumoral
16.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 37(9): 1169-1176, 2023 Sep 15.
Artículo en Chino | MEDLINE | ID: mdl-37718433

RESUMEN

Objective: To review the research progress in biotherapy of rotator cuff injury in recent years, in order to provide help for clinical decision-making of rotator cuff injury treatment. Methods: The literature related to biotherapy of rotator cuff injury at home and abroad in recent years was widely reviewed, and the mechanism and efficacy of biotherapy for rotator cuff injury were summarized from the aspects of platelet-rich plasma (PRP), growth factors, stem cells, and exosomes. Results: In order to relieve patients' pain, improve upper limb function, and improve quality of life, the treatment of rotator cuff injury experienced an important change from conservative treatment to open surgery to arthroscopic rotator cuff repair. Arthroscopic rotator cuff repair plus a variety of biotherapy methods have become the mainstream of clinical treatment. All kinds of biotherapy methods have ideal mid- and long-term effectiveness in the repair of rotator cuff injury. The biotherapy method to promote the healing of rotator cuff injury is controversial and needs to be further studied. Conclusion: All kinds of biotherapy methods show a good effect on the repair of rotator cuff injury. It will be an important research direction to further develop new biotherapy technology and verify its effectiveness.


Asunto(s)
Exosomas , Lesiones del Manguito de los Rotadores , Humanos , Artroplastia , Calidad de Vida , Lesiones del Manguito de los Rotadores/terapia , Productos Biológicos/uso terapéutico
17.
Protein Cell ; 14(9): 653-667, 2023 09 14.
Artículo en Inglés | MEDLINE | ID: mdl-37707322

RESUMEN

Lipophagy, the selective engulfment of lipid droplets (LDs) by autophagosomes for lysosomal degradation, is critical to lipid and energy homeostasis. Here we show that the lipid transfer protein ORP8 is located on LDs and mediates the encapsulation of LDs by autophagosomal membranes. This function of ORP8 is independent of its lipid transporter activity and is achieved through direct interaction with phagophore-anchored LC3/GABARAPs. Upon lipophagy induction, ORP8 has increased localization on LDs and is phosphorylated by AMPK, thereby enhancing its affinity for LC3/GABARAPs. Deletion of ORP8 or interruption of ORP8-LC3/GABARAP interaction results in accumulation of LDs and increased intracellular triglyceride. Overexpression of ORP8 alleviates LD and triglyceride deposition in the liver of ob/ob mice, and Osbpl8-/- mice exhibit liver lipid clearance defects. Our results suggest that ORP8 is a lipophagy receptor that plays a key role in cellular lipid metabolism.


Asunto(s)
Autofagia , Gotas Lipídicas , Animales , Ratones , Autofagosomas , Homeostasis , Triglicéridos
18.
Angew Chem Int Ed Engl ; 62(45): e202311223, 2023 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-37721360

RESUMEN

Zeolitic metal-organic frameworks (ZMOFs) have emerged as one of the most promsing catalysts for energy conversion, but they suffer from either weak bonding between metal-organic cubes (MOCs) that decrease their stability during catalysis processes or low activity due to inadequate active sites. In this work, through ligand-directing strategy, we successfully obtain an unprecedented bismuth-based ZMOF (Bi-ZMOF) featuring a ACO topological crystal structure with strong coordination bonding between the Bi-based cages. As a result, it enables efficient reduction of CO2 to formic acid (HCOOH) with Faradaic efficiency as high as 91 %. A combination of in situ surface-enhanced infrared absorption spectroscopy and density functional theory calculation reveals that the Bi-N coordination contributes to facilitating charge transfer from N to Bi atoms, which stabilize the intermediate to boost the reduction efficiency of CO2 to HCOOH. This finding highlights the importance of the coordination environment of metal active sites on electrocatalytic CO2 reduction. We believe that this work will offer a new clue to rationally design zeolitic MOFs for catalytic reaction.

19.
Materials (Basel) ; 16(16)2023 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-37630002

RESUMEN

This paper develops the mechanical and durable samples of C50 high-performance concrete, studies the mechanical properties, crack resistance, sulfate attack resistance, frost resistance, and impermeability of concrete with different mineral admixtures of mineral powder and fly ash, and obtains the best mineral admixture of mineral powder and fly ash to improve the performance of high-performance concrete. The results show that the doping effect is the best when the ratio of prepared mineral powder to fly ash is 3:2. With the increase in the mineral powder-fly ash admixture, the slump and expansion of high-performance concrete decrease rapidly at first and then slowly. In total, 60% doping is the turning point; the compressive and flexural strengths of concrete decreased slowly at first and then rapidly. Taking 30% of the admixture as the turning point, 35% of the mineral powder fly ash is generally selected. By mixing and adding a certain proportion of fly ash and mineral powder admixtures, the crack resistance of concrete is enhanced, and the shrinkage and cracking are reduced. The corrosion resistance coefficient will exceed 88%, the relative dynamic elastic modulus will exceed 95%, and the impermeability grade will reach P17. The durability of concrete can be improved by adding mineral admixtures.

20.
Zhejiang Da Xue Xue Bao Yi Xue Ban ; 52(4): 397-405, 2023 Aug 25.
Artículo en Inglés, Chino | MEDLINE | ID: mdl-37643974

RESUMEN

Long non-coding RNAs (lncRNAs) which are usually thought to have no protein coding ability, are widely involved in cell proliferation, signal transduction and other biological activities. However, recent studies have suggested that short open reading frames (sORFs) of some lncRNAs can encode small functional peptides (micropeptides). These micropeptides appear to play important roles in calcium homeostasis, embryonic development and tumorigenesis, suggesting their potential as therapeutic targets and diagnostic biomarkers. Currently, bioinformatic tools as well as experimental methods such as ribosome mapping and in vitro translation are applied to predict the coding potential of lncRNAs. Furthermore, mass spectrometry, specific antibodies and epitope tags are used for validating the expression of micropeptides. Here, we review the physiological and pathological functions of recently identified micropeptides as well as research strategies for predicting the coding potential of lncRNAs to facilitate the further research of lncRNA encoded micropeptides.


Asunto(s)
ARN Largo no Codificante , Femenino , Embarazo , Humanos , ARN Largo no Codificante/genética , Proyectos de Investigación , Anticuerpos , Carcinogénesis , Micropéptidos
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