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1.
Transl Lung Cancer Res ; 13(8): 1816-1827, 2024 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-39263012

RESUMEN

Background: Early-stage invasive lung adenocarcinoma (ADC) characterized by a predominant micropapillary or solid pattern exhibit an elevated risk of recurrence following sub-lobar resection, thus determining histological subtype of early-stage invasive ADC prior surgery is important for formulating lobectomy or sub-lobar resection. This study aims to develop a deep learning algorithm and assess its clinical capability in distinguishing high-risk or low-risk histologic patterns in early-stage invasive ADC based on preoperative computed tomography (CT) scans. Methods: Two retrospective cohorts were included: development cohort 1 and external test cohort 2, comprising patients diagnosed with T1 stage invasive ADC. Electronic medical records and CT scans of all patients were documented. Patients were stratified into two risk groups. High-risk group: comprising cases with a micropapillary component ≥5% or a predominant solid pattern. Low-risk group: encompassing cases with a micropapillary component <5% and an absence of a predominant solid pattern. The overall segmentation model was modified based on Mask Region-based Convolutional Neural Network (Mask-RCNN), and Residual Network 50 (ResNet50)_3D was employed for image classification. Results: A total of 432 patients participated in this study, with 385 cases in cohort 1 and 47 cases in cohort 2. The fine-outline results produced by the auto-segmentation model exhibited a high level of agreement with manual segmentation by human experts, yielding a mean dice coefficient of 0.86 [95% confidence interval (CI): 0.85-0.87] in cohort 1 and 0.84 (95% CI: 0.82-0.85) in cohort 2. Furthermore, the deep learning model effectively differentiated the high-risk group from the low-risk group, achieving an area under the curve (AUC) of 0.89 (95% CI: 0.88-0.90) in cohort 1. In the external validation conducted in cohort 2, the deep learning model displayed an AUC of 0.87 (95% CI: 0.84-0.88) in distinguishing the high-risk group from the low-risk group. The average diagnostic time was 16.00±3.2 seconds, with an accuracy of 0.82 (95% CI: 0.81-0.83). Conclusions: We have developed a deep learning algorithm, LungPath, for the automated segmentation of pulmonary nodules and prediction of high-risk histological patterns in early-stage lung ADC based on CT scans.

2.
Front Surg ; 11: 1394575, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39268495

RESUMEN

In femoral intertrochanteric fractures, poor incision positioning may result in inaccurate intramedullary nail placement direction, which increases the difficulty of reduction and thus the size and number of incisions. Repeated intraoperative fluoroscopy not only increases the radiation exposure of the surgeon but also affects the operative outcomes. This technical note proposes a method of identifying incision positioning preoperatively using the "3-2-1" body surface localization method. This auxiliary positioning technique uses a body surface locator and the lower limb force axis. It can predict the incisions for the needle insertion point, spiral blade, and locking nails, create minimally invasive incisions, avoid incorrect incision position, facilitate accurate intraoperative intramedullary nail placement, reduce the incision size, intraoperative bleeding, and radiation exposure, and improve surgical efficiency and reduction quality.

3.
Microb Pathog ; 195: 106893, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39197333

RESUMEN

BACKGROUND: Vaccination is the best way to prevent influenza virus infection, and insufficient antibodies make it difficult to resist influenza virus invasion. Astragalus Polysaccharide (APS) has a boosting effect on immunity, so we evaluate the effect of APS as an immune adjuvant for H1N1 influenza vaccines in this study. METHODS: The mice were immunized twice with influenza A (H1N1) vaccine and APS. Subsequently, the serum antibody levels were assessed using enzyme-linked immunosorbent assay (ELISA). The frequency of peripheral immune T cells was determined by flow cytometry. Following this, the immunized mice were exposed to a lethal dose of the virus, and changes in body weight and survival rates were recorded. Hematoxylin-eosin staining was employed to observe pathological alterations in lung and intestinal tissues. Western blot analysis was conducted to detect the expression of intestinal barrier function proteins (Occludin and Claudin-1). ELISA was utilized to measure the expression level of serum inflammatory cytokine TNF-α. Fresh mouse feces were collected after the initial immunization as well as after viral infection for 16S rRNA analysis aimed at detecting alterations in gut microbiota. RESULTS: Compared to the Hemagglutinin (HA) group, the APS group demonstrated higher levels of immunoglobulin G (IgG), IgG1, and IgG3, as well as neutralizing antibody levels. Additionally, it increased the frequency of CD8+ cells to enhance resistance against lethal infection. On day 14 post-infection, the high-dose APS group exhibited a higher survival rate (71.40 %) compared to the HA group (14.28 %), along with faster weight recovery. Furthermore, APS was found to ameliorate alveolar damage in lung tissue and rectify intestinal structural disorder. It also upregulated the expression levels of tight junction proteins Occludin and Claudin-1 in intestinal tissue while reducing serum TNF-α expression levels. In addition, populations of Colidextribacter, Peptococcaceae, and Ruminococcaceae were the dominant gut microbiota in the APS group after viral infection. CONCLUSION: APS has an immune-enhancing effect and is expected to be a novel adjuvant in the H1N1 influenza vaccine.


Asunto(s)
Adyuvantes Inmunológicos , Anticuerpos Antivirales , Planta del Astrágalo , Microbioma Gastrointestinal , Subtipo H1N1 del Virus de la Influenza A , Vacunas contra la Influenza , Ratones Endogámicos BALB C , Infecciones por Orthomyxoviridae , Polisacáridos , Animales , Vacunas contra la Influenza/inmunología , Subtipo H1N1 del Virus de la Influenza A/inmunología , Ratones , Polisacáridos/farmacología , Planta del Astrágalo/química , Microbioma Gastrointestinal/efectos de los fármacos , Infecciones por Orthomyxoviridae/prevención & control , Infecciones por Orthomyxoviridae/inmunología , Anticuerpos Antivirales/sangre , Pulmón/patología , Pulmón/inmunología , Inmunoglobulina G/sangre , Femenino , Anticuerpos Neutralizantes/sangre , Factor de Necrosis Tumoral alfa/metabolismo , Heces/microbiología , ARN Ribosómico 16S/genética , Ocludina/metabolismo , Claudina-1/metabolismo
4.
Cell Mol Life Sci ; 81(1): 303, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-39008099

RESUMEN

Vitamin C (VC) serves as a pivotal nutrient for anti-oxidation process, metabolic responses, and stem cell differentiation. However, its precise contribution to placenta development and gestation remains obscure. Here, we demonstrated that physiological levels of VC act to stabilize Hand1, a key bHLH transcription factor vital for the development trajectory of trophoblast giant cell (TGC) lineages, thereby promoting the differentiation of trophoblast stem cells into TGC. Specifically, VC administration inactivated c-Jun N-terminal kinase (JNK) signaling, which directly phosphorylates Hand1 at Ser48, triggering the proteasomal degradation of Hand1. Conversely, a loss-of-function mutation at Ser48 on Hand1 not only significantly diminished both intrinsic and VC-induced stabilization of Hand1 but also underscored the indispensability of this residue. Noteworthy, the insufficiency of VC led to severe defects in the differentiation of diverse TGC subtypes and the formation of labyrinth's vascular network in rodent placentas, resulting in failure of maintenance of pregnancy. Importantly, VC deficiency, lentiviral knockdown of JNK or overexpression of Hand1 mutants in trophectoderm substantially affected the differentiation of primary and secondary TGC in E8.5 mouse placentas. Thus, these findings uncover the significance of JNK inactivation and consequential stabilization of Hand1 as a hitherto uncharacterized mechanism controlling VC-mediated placentation and perhaps maintenance of pregnancy.


Asunto(s)
Ácido Ascórbico , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico , Diferenciación Celular , Proteínas Quinasas JNK Activadas por Mitógenos , Placentación , Trofoblastos , Animales , Femenino , Embarazo , Ácido Ascórbico/farmacología , Ácido Ascórbico/metabolismo , Placentación/genética , Ratones , Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , Proteínas Quinasas JNK Activadas por Mitógenos/genética , Diferenciación Celular/efectos de los fármacos , Trofoblastos/metabolismo , Trofoblastos/efectos de los fármacos , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Placenta/metabolismo , Fosforilación , Humanos , Ratones Endogámicos C57BL
5.
J Hazard Mater ; 477: 135311, 2024 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-39068889

RESUMEN

Face masks have emerged as a significant source of microplastics (MPs) under the influence of biotic and abiotic interactions. However, the combined effects of abiotic photoaging and biofilm-loading on mask-derived MPs as carriers of metal ions are not clear. We investigated the Pb(Ⅱ) adsorption onto polypropylene (PP) and polyurethane (PU) mask-derived MPs treated by photoaging, biofilm-loading, and both combinations, evaluating the composite risks. PU mask-derived MPs (1.157.47 mg/g) exhibited greater Pb(Ⅱ) adsorption capacity than PP mask-derived MPs (0.842.08 mg/g) because of the presence of intrinsic carbonyl functional groups. Photoaging (30.5%, 88.4%), biofilm-loading (110.7%, 87.1%), and both combinations (146.7%, 547.0%) of PP and PU masks enhanced Pb(Ⅱ) adsorption compared to virgin mask-derived MPs due to the increase of oxygen-containing functional groups. High-throughput sequencing indicated that the structural morphology and chemical composition of masks significantly affected the microbial community. Adsorption mechanisms involved electrostatic force and surface complexation. A combination of photoaging and biofilms increased the ecological risk index of mask-derived MPs in freshwater, showing the risk level to be high (PP mask) and very high (PU mask). This research highlights the crucial role of photoaging combined with biofilms in controlling metal ion adsorption onto mask-derived MPs, thereby increasing the composite risks.


Asunto(s)
Biopelículas , Plomo , Microplásticos , Polipropilenos , Poliuretanos , Adsorción , Plomo/química , Poliuretanos/química , Polipropilenos/química , Microplásticos/química , Microplásticos/toxicidad , Contaminantes Químicos del Agua/química , Máscaras
6.
Small ; : e2403419, 2024 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-38970539

RESUMEN

The conductive carbon-based interlayer, as the secondary current collector in the self-dissolving battery system, can effectively capture escaping cathode active materials, inducing deep release of remaining capacity. In the multi-step reactions of Li─S batteries, the environmental tolerance of the conductive carbon-based interlayer to polysulfides determines the inhibition of shuttle effects. Here, a modified metal-organic framework (Mn-ZIF67) is utilized to obtain nitrogen-doped carbon-coated heterogeneous Co-MnO (Co-MnO@NC) with dual catalytic center for the functional interlayer materials. The synergistic coupling mechanism of NC and Co-MnO achieves rapid deposition and conversion of free polysulfide and fragmented active sulfur on the secondary current collector, reducing capacity loss in the cathode. The Li─S battery with Co-MnO@NC/PP separator maintains an initial capacity of 1050 mAh g-1 (3C) and excellent cycle stability (0.056% capacity decay rate). Under extreme testing conditions (S load = 5.82 mg cm-2, E/S = 9.1 µL mg-1), a reversible capacity of 501.36 mAh g-1 is observed after 200 cycles at 0.2 C, showing good further practical reliability. This work demonstrates the advancement application of Co-MnO@NC bimetallic heterojunctions catalysts in the secondary current collector for high-performance Li─S batteries, thereby providing guidance for the development of interlayer in various dissolution systems.

7.
Cell Biochem Biophys ; 2024 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-39020087

RESUMEN

To investigate vascular endothelium damage in rats exposed to hypoxic and cold and the effect of salidroside in protecting against this damage. A rat isolated aortic ring hypoxia/cold model was established to simulate exposure to hypoxic and cold. The levels of endothelial cell injury markers were measured by ELISA. TEM was performed to observe the ultrastructure of vascular ring endothelial cells. In vitro assays were performed to verify the effect of salidroside on endothelial cells. CCK-8 and flow cytometry were performed to analyze endothelial cell survival and apoptosis, respectively. Ca2+ concentrations were measured by Flow cytometry, and the expressions of NOS/NO pathway-related proteins were measured by WB. Endothelial cell damage, mitochondrial swelling, autophagy, and apoptosis were increased in the hypoxia group and hypoxia/hypothermia group. All of these effects were inhibited by salidroside. Moreover, exposure to cold combined with hypoxia reduced the NO levels, Ca2+ concentrations and NOS/NO pathway-related protein expression in the hypoxia group and hypoxia/hypothermia group. Salidroside treatment reversed these changes. Salidroside protected against endothelial cell injury induced by cold and hypoxia through reduction of Ca2+-CaM-CAMKII-dependent eNOS/NO activation, thereby preventing mitochondrial damage, reducing ROS levels, and inhibiting apoptosis.

8.
Materials (Basel) ; 17(13)2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38998290

RESUMEN

Electropolishing (EP) has become a standard procedure for treating the inner surfaces of superconducting radio-frequency (SRF) cavities composed of pure niobium. In this study, a new EP facility was employed for the surface treatment of both 1.3 GHz and 3.9 GHz single-cell cavities at the Wuxi Platform. The stable "cold EP" mode was successfully implemented on this newly designed EP facility. By integrating the cold EP process with a two-step baking approach, a maximum accelerating gradient exceeding 40 MV/m was achieved in 1.3 GHz single-cell cavities. Additionally, an update to this EP facility involved the design of a special cathode system for small-aperture structures, facilitating the cold EP process for 3.9 GHz single-cell cavities. Ultimately, a maximum accelerating gradient exceeding 25 MV/m was attained in the 3.9 GHz single-cell cavities after undergoing the cold EP treatment. The design and commissioning of the EP device, as well as the electropolishing and vertical test results of the single-cell cavities, will be detailed herein. These methods and experiences are also transferable to multi-cell cavities and elliptical cavities of other frequencies.

9.
Heliyon ; 10(14): e34436, 2024 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-39082013

RESUMEN

Current commercial separators used in lithium-ion batteries have inherent flaws, especially poor thermal stability, which pose substantial safety risks. This study introduces a high-safety composite membrane made from electrospun poly(vinyl alcohol)-melamine (PVAM) and polyvinylidene fluoride (PVDF) polymer solutions via a dip coating method, designed for high-voltage battery systems. The poly(vinyl alcohol) and melamine components enhance battery safety, while the PVDF coating improves lithium-ion conductivity. The dip-coated PVDF/Esp-PVAM composite separators were evaluated for electrolyte uptake, contact angle, thermal stability, porosity, electrochemical stability and ionic conductivity. Notably, our Dip 1 % PVDF@Esp-PVAM composite separator exhibited excellent wettability and a lithium-ion conductivity of approximately 7.75 × 10⁻4 S cm⁻1 at room temperature. These separators outperformed conventional PE separators in half-cells with Ni-rich NCM811 cathodes, showing exceptional cycling stability with 93.4 % capacity retention after 100 cycles at 1C/1C, as compared to 84.8 % for PE separators. Our Dip 1 % PVDF@Esp-PVAM composite separator demonstrates significant potential for enhancing the long-term durability and high-rate performance of lithium-ion batteries, making it a promising option for long-term energy storage applications.

10.
Front Biosci (Landmark Ed) ; 29(6): 221, 2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-38940044

RESUMEN

The endoplasmic reticulum (ER) played an important role in the folding, assembly and post-translational modification of proteins. ER homeostasis could be disrupted by the accumulation of misfolded proteins, elevated reactive oxygen species (ROS) levels, and abnormal Ca2+ signaling, which was referred to ER stress (ERS). Ferroptosis was a unique programmed cell death model mediated by iron-dependent phospholipid peroxidation and multiple signaling pathways. The changes of mitochondrial structure, the damage of glutathione peroxidase 4 (GPX4) and excess accumulation of iron were the main characteristics of ferroptosis. ROS produced by ferroptosis can interfere with the activity of protein-folding enzymes, leading to the accumulation of large amounts of unfolded proteins, thus causing ERS. On the contrary, the increase of ERS level could promote ferroptosis by the accumulation of iron ion and lipid peroxide, the up-regulation of ferroptosis related genes. At present, the studies on the relationship between ferroptosis and ERS were one-sided and lack of in-depth studies on the interaction mechanism. This review aimed to explore the molecular mechanism of cross-talk between ferroptosis and ERS, and provide new strategies and targets for the treatment of liver diseases.


Asunto(s)
Estrés del Retículo Endoplásmico , Ferroptosis , Hepatopatías , Especies Reactivas de Oxígeno , Ferroptosis/fisiología , Humanos , Hepatopatías/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Animales , Transducción de Señal , Hierro/metabolismo , Peroxidación de Lípido , Retículo Endoplásmico/metabolismo
11.
Opt Express ; 32(11): 19467-19479, 2024 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-38859081

RESUMEN

Computational micro-spectrometers comprised of detector arrays and encoding structure arrays, such as on-chip Fabry-Perot (FP) cavity filters, have great potential in many in-situ applications owing to their compact size and snapshot imaging ability. Given manufacturing deviation and environmental influence are inevitable, easy and effective calibration for spectrometer is necessary, especially for in-situ applications. Currently calibration strategies based on iterative algorithms or neural networks require accurate measurements of pixel-level (spectral) encoding functions through monochromator or large amounts of standard samples. These procedures are time-consuming and expensive, thereby impeding in-situ applications. Meta-learning algorithms with few-shot learning ability can address this challenge by incorporating the prior knowledge in the simulated dataset. In this work, we propose a meta-learning algorithm free of measuring encoding function or large amounts of standard samples to calibrate a micro-spectrometer with manufacturing deviation effectively. Our micro-spectrometer comprises 16 types of FP filters covering a wavelength range of 550-720 nm. The center wavelength of each filter type deviates from the design up to 6 nm. After calibration with 15 different color data, the average reconstruction error on the test dataset decreased from 7.2 × 10-3 to 1.2 × 10-3, and further decreased to 9.4 × 10-4 when the calibration data increased to 24. The performance is comparable to algorithms trained with measured encoding function both in reconstruction error and generalization ability. We estimated that the cost of in-situ calibration through reflectance measurements of color chart decreased to one percent of the cost through monochromator measurements. By exploiting prior deviation information in simulation data with meta-learning, the efficiency and cost of calibration are significantly improved, thereby facilitating the large-scale production and in-situ application of micro-spectrometers.

12.
Org Lett ; 26(24): 5136-5140, 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38847357

RESUMEN

Herein, we report a rhodium-catalyzed C-H activation/[4+2] cyclization reaction between α,ß-unsaturated amides and iodonium ylides for the synthesis of novel 7,8-dihydroquinoline-2,5-diones and analogues. This protocol provides a series of pyridones fused with saturated cycles with good functional group compatibility, good water and air tolerance, and good to excellent yields under mild and green reaction conditions. Additionally, scale-up synthesis can be smoothly performed with as low as 0.25 mol % catalyst loading. Recycling experiments and different transformation experiments were also carried out to demonstrate the potential synthetic utility of this protocol.

14.
Proc Natl Acad Sci U S A ; 121(19): e2315348121, 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38701117

RESUMEN

Ovarian cancer is an aggressive gynecological tumor characterized by a high relapse rate and chemoresistance. Ovarian cancer exhibits the cancer hallmark of elevated glycolysis, yet effective strategies targeting cancer cell metabolic reprogramming to overcome therapeutic resistance in ovarian cancer remain elusive. Here, we revealed that epigenetic silencing of Otubain 2 (OTUB2) is a driving force for mitochondrial metabolic reprogramming in ovarian cancer, which promotes tumorigenesis and chemoresistance. Mechanistically, OTUB2 silencing destabilizes sorting nexin 29 pseudogene 2 (SNX29P2), which subsequently prevents hypoxia-inducible factor-1 alpha (HIF-1α) from von Hippel-Lindau tumor suppressor-mediated degradation. Elevated HIF-1α activates the transcription of carbonic anhydrase 9 (CA9) and drives ovarian cancer progression and chemoresistance by promoting glycolysis. Importantly, pharmacological inhibition of CA9 substantially suppressed tumor growth and synergized with carboplatin in the treatment of OTUB2-silenced ovarian cancer. Thus, our study highlights the pivotal role of OTUB2/SNX29P2 in suppressing ovarian cancer development and proposes that targeting CA9-mediated glycolysis is an encouraging strategy for the treatment of ovarian cancer.


Asunto(s)
Anhidrasa Carbónica IX , Silenciador del Gen , Mitocondrias , Neoplasias Ováricas , Tioléster Hidrolasas , Animales , Femenino , Humanos , Ratones , Antígenos de Neoplasias/metabolismo , Antígenos de Neoplasias/genética , Anhidrasa Carbónica IX/metabolismo , Anhidrasa Carbónica IX/genética , Línea Celular Tumoral , Resistencia a Antineoplásicos/genética , Resistencia a Antineoplásicos/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Glucólisis/efectos de los fármacos , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Reprogramación Metabólica , Mitocondrias/metabolismo , Mitocondrias/efectos de los fármacos , Neoplasias Ováricas/genética , Neoplasias Ováricas/metabolismo , Neoplasias Ováricas/patología , Neoplasias Ováricas/tratamiento farmacológico , Tioléster Hidrolasas/genética
16.
Anal Biochem ; 692: 115552, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38718956

RESUMEN

The reactive nitrogen species (RNS) in lysosomes play a major role during the regulation of lysosomal microenvironment. Nitroxyl (HNO) belongs to active nitrogen species (RNS) and is becoming a potential diagnostic and therapeutic biomarker. However, the complex synthesis routes of HNO in biosystem always hinder the exact determination of HNO in living cells. Here, a rhodamine-based fluorescent probe used to determine nitroxyl (HNO) in lysosomes was constructed and synthesized. 2-(Diphenylphosphino)benzoate was utilized as the sensing unit for HNO and morpholine was chose as the targeting group for lysosome. Before the addition of HNO, the probe displayed a spirolactone structure and almost no fluorescence was found. After the addition of HNO, the probe existed as a conjugated xanthene form and an intense green fluorescence was observed. The fluorescent probe possessed fast response (3 min) and high selectivity for HNO. Furthermore, fluorescence intensity of the probe linearly related with the HNO concentration in the range of 6.0 × 10-8 to 6.0 × 10-5 mol L-1. The detection limit was found to be 1.87 × 10-8 mol L-1 for HNO. Moreover, the probe could selectively targeted lysosome with excellent biocompatibility and had been effectually utilized to recognize exogenous HNO in A549 cells.


Asunto(s)
Colorantes Fluorescentes , Lisosomas , Óxidos de Nitrógeno , Rodaminas , Colorantes Fluorescentes/química , Colorantes Fluorescentes/síntesis química , Lisosomas/metabolismo , Óxidos de Nitrógeno/análisis , Óxidos de Nitrógeno/química , Humanos , Rodaminas/química , Rodaminas/síntesis química
17.
ACS Sens ; 9(6): 2793-2800, 2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38820066

RESUMEN

Nitric oxide (NO) plays a pivotal role as a biological signaling molecule, presenting challenges in its specific detection and differentiation from other reactive nitrogen and oxygen species within living organisms. Herein, a 18F-labeled (fluorine-18, t1/2 = 109.7 min) small-molecule tracer dimethyl 4-(4-(4-[18F]fluorobutoxy)benzyl)-2,6-dimethyl-1,4-dihydropyridine-3,5-dicarboxylate ([18F]BDHP) is developed based on the dihydropyridine scaffold for positron emission tomography (PET) imaging of NO in vivo. [18F]BDHP exhibits a highly sensitive and efficient C-C cleavage reaction specifically triggered by NO under physiological conditions, leading to the production of a 18F-labeled radical that is readily retained within the cells. High uptakes of [18F]BDHP are found within and around NO-generating cells, such as macrophages treated with lipopolysaccharide or benzo(a)pyrene. MicroPET/CT imaging of arthritic animal model mice reveals distinct tracer accumulation in the arthritic legs, showcasing a higher distribution of NO compared with the control legs. In summary, a specific radical-generating dihydropyridine tracer with a unique radical retention strategy has been established for the marking of NO in real-time in vivo.


Asunto(s)
Dihidropiridinas , Radioisótopos de Flúor , Óxido Nítrico , Tomografía de Emisión de Positrones , Animales , Óxido Nítrico/metabolismo , Óxido Nítrico/química , Ratones , Dihidropiridinas/química , Tomografía de Emisión de Positrones/métodos , Radioisótopos de Flúor/química , Radicales Libres/química , Células RAW 264.7
18.
Nature ; 630(8015): 198-205, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38720074

RESUMEN

Phosphoinositide-3-kinase-γ (PI3Kγ) is implicated as a target to repolarize tumour-associated macrophages and promote antitumour immune responses in solid cancers1-4. However, cancer cell-intrinsic roles of PI3Kγ are unclear. Here, by integrating unbiased genome-wide CRISPR interference screening with functional analyses across acute leukaemias, we define a selective dependency on the PI3Kγ complex in a high-risk subset that includes myeloid, lymphoid and dendritic lineages. This dependency is characterized by innate inflammatory signalling and activation of phosphoinositide 3-kinase regulatory subunit 5 (PIK3R5), which encodes a regulatory subunit of PI3Kγ5 and stabilizes the active enzymatic complex. We identify p21 (RAC1)-activated kinase 1 (PAK1) as a noncanonical substrate of PI3Kγ that mediates this cell-intrinsic dependency and find that dephosphorylation of PAK1 by PI3Kγ inhibition impairs mitochondrial oxidative phosphorylation. Treatment with the selective PI3Kγ inhibitor eganelisib is effective in leukaemias with activated PIK3R5. In addition, the combination of eganelisib and cytarabine prolongs survival over either agent alone, even in patient-derived leukaemia xenografts with low baseline PIK3R5 expression, as residual leukaemia cells after cytarabine treatment have elevated G protein-coupled purinergic receptor activity and PAK1 phosphorylation. Together, our study reveals a targetable dependency on PI3Kγ-PAK1 signalling that is amenable to near-term evaluation in patients with acute leukaemia.


Asunto(s)
Fosfatidilinositol 3-Quinasa Clase Ib , Leucemia , Transducción de Señal , Quinasas p21 Activadas , Animales , Humanos , Ratones , Línea Celular , Fosfatidilinositol 3-Quinasa Clase Ib/genética , Fosfatidilinositol 3-Quinasa Clase Ib/metabolismo , Citarabina/farmacología , Citarabina/uso terapéutico , Leucemia/tratamiento farmacológico , Leucemia/enzimología , Leucemia/genética , Leucemia/metabolismo , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Fosforilación Oxidativa/efectos de los fármacos , Quinasas p21 Activadas/antagonistas & inhibidores , Quinasas p21 Activadas/metabolismo , Fosforilación , Ensayos Antitumor por Modelo de Xenoinjerto
19.
Nat Plants ; 10(3): 469-482, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-38448725

RESUMEN

N6-methyladenosine (m6A) is the most abundant internal modification in eukaryotic mRNAs, yet how plants recognize this chemical modification to swiftly adjust developmental plasticity under environmental stresses remains unclear. Here we show that m6A mRNA modification and its reader protein EVOLUTIONARILY CONSERVED C-TERMINAL REGION 8 (ECT8) act together as a key checkpoint for negative feedback regulation of abscisic acid (ABA) signalling by sequestering the m6A-modified ABA receptor gene PYRABACTIN RESISTANCE 1-LIKE 7 (PYL7) via phase-separated ECT8 condensates in stress granules in response to ABA. This partially depletes PYL7 mRNA from its translation in the cytoplasm, thus reducing PYL7 protein levels and compromising ABA perception. The loss of ECT8 results in defective sequestration of m6A-modified PYL7 in stress granules and permits more PYL7 transcripts for translation. This causes overactivation of ABA-responsive genes and the consequent ABA-hypersensitive phenotypes, including drought tolerance. Overall, our findings reveal that m6A-mediated sequestration of PYL7 by ECT8 in stress granules negatively regulates ABA perception, thereby enabling prompt feedback regulation of ABA signalling to prevent plant cell overreaction to environmental stresses.


Asunto(s)
Adenosina/análogos & derivados , Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Ácido Abscísico/metabolismo , Retroalimentación , ARN Mensajero/genética , ARN Mensajero/metabolismo , Percepción , Regulación de la Expresión Génica de las Plantas , Estrés Fisiológico/genética , Sequías , Plantas Modificadas Genéticamente/genética
20.
Food Chem X ; 21: 101240, 2024 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-38434690

RESUMEN

Encapsulation technology has been extensively used to enhance the stability, specificity, and bioavailability of essential food ingredients. Additionally, it plays a vital role in improving product quality and reducing production costs. This study presents a comprehensive classification of encapsulation techniques based on the state of different cores (solid, liquid, and gaseous) and offers a detailed description and analysis of these encapsulation methods. Specifically, it introduces the diverse applications of encapsulation technology in food, encompassing areas such as antioxidant, protein activity, physical stability, controlled release, delivery, antibacterial, and probiotics. The potential impact of encapsulation technology is expected to make encapsulation technology a major process and research hotspot in the food industry. Future research directions include applications of encapsulation for enzymes, microencapsulation of biosensors, and novel technologies such as self-assembly. This study provides a valuable theoretical reference for the in-depth research and wide application of encapsulation technology in the food industry.

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