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1.
Nature ; 628(8007): 299-305, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38438066

RESUMEN

Perovskite solar cells (PSCs) are among the most promising photovoltaic technologies owing to their exceptional optoelectronic properties1,2. However, the lower efficiency, poor stability and reproducibility issues of large-area PSCs compared with laboratory-scale PSCs are notable drawbacks that hinder their commercialization3. Here we report a synergistic dopant-additive combination strategy using methylammonium chloride (MACl) as the dopant and a Lewis-basic ionic-liquid additive, 1,3-bis(cyanomethyl)imidazolium chloride ([Bcmim]Cl). This strategy effectively inhibits the degradation of the perovskite precursor solution (PPS), suppresses the aggregation of MACl and results in phase-homogeneous and stable perovskite films with high crystallinity and fewer defects. This approach enabled the fabrication of perovskite solar modules (PSMs) that achieved a certified efficiency of 23.30% and ultimately stabilized at 22.97% over a 27.22-cm2 aperture area, marking the highest certified PSM performance. Furthermore, the PSMs showed long-term operational stability, maintaining 94.66% of the initial efficiency after 1,000 h under continuous one-sun illumination at room temperature. The interaction between [Bcmim]Cl and MACl was extensively studied to unravel the mechanism leading to an enhancement of device properties. Our approach holds substantial promise for bridging the benchtop-to-rooftop gap and advancing the production and commercialization of large-area perovskite photovoltaics.

2.
Nature ; 617(7962): 717-723, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37225883

RESUMEN

Flexible solar cells have a lot of market potential for application in photovoltaics integrated into buildings and wearable electronics because they are lightweight, shockproof and self-powered. Silicon solar cells have been successfully used in large power plants. However, despite the efforts made for more than 50 years, there has been no notable progress in the development of flexible silicon solar cells because of their rigidity1-4. Here we provide a strategy for fabricating large-scale, foldable silicon wafers and manufacturing flexible solar cells. A textured crystalline silicon wafer always starts to crack at the sharp channels between surface pyramids in the marginal region of the wafer. This fact enabled us to improve the flexibility of silicon wafers by blunting the pyramidal structure in the marginal regions. This edge-blunting technique enables commercial production of large-scale (>240 cm2), high-efficiency (>24%) silicon solar cells that can be rolled similarly to a sheet of paper. The cells retain 100% of their power conversion efficiency after 1,000 side-to-side bending cycles. After being assembled into large (>10,000 cm2) flexible modules, these cells retain 99.62% of their power after thermal cycling between -70 °C and 85 °C for 120 h. Furthermore, they retain 96.03% of their power after 20 min of exposure to air flow when attached to a soft gasbag, which models wind blowing during a violent storm.

3.
Nature ; 601(7894): 573-578, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-35082415

RESUMEN

Owing to rapid development in their efficiency1 and stability2, perovskite solar cells are at the forefront of emerging photovoltaic technologies. State-of-the-art cells exhibit voltage losses3-8 approaching the theoretical minimum and near-unity internal quantum efficiency9-13, but conversion efficiencies are limited by the fill factor (<83%, below the Shockley-Queisser limit of approximately 90%). This limitation results from non-ideal charge transport between the perovskite absorber and the cell's electrodes5,8,13-16. Reducing the electrical series resistance of charge transport layers is therefore crucial for improving efficiency. Here we introduce a reverse-doping process to fabricate nitrogen-doped titanium oxide electron transport layers with outstanding charge transport performance. By incorporating this charge transport material into perovskite solar cells, we demonstrate 1-cm2 cells with fill factors of >86%, and an average fill factor of 85.3%. We also report a certified steady-state efficiency of 22.6% for a 1-cm2 cell (23.33% ± 0.58% from a reverse current-voltage scan).

4.
Nature ; 594(7861): 41-45, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-34079139

RESUMEN

Owing to the inevitable loss in communication channels, the distance of entanglement distribution is limited to approximately 100 kilometres on the ground1. Quantum repeaters can circumvent this problem by using quantum memory and entanglement swapping2. As the elementary link of a quantum repeater, the heralded distribution of two-party entanglement between two remote nodes has only been realized with built-in-type quantum memories3-9. These schemes suffer from the trade-off between multiplexing capacity and deterministic properties and hence hinder the development of efficient quantum repeaters. Quantum repeaters based on absorptive quantum memories can overcome such limitations because they separate the quantum memories and the quantum light sources. Here we present an experimental demonstration of heralded entanglement between absorptive quantum memories. We build two nodes separated by 3.5 metres, each containing a polarization-entangled photon-pair source and a solid-state quantum memory with bandwidth up to 1 gigahertz. A joint Bell-state measurement in the middle station heralds the successful distribution of maximally entangled states between the two quantum memories with a fidelity of 80.4 ± 2.2 per cent (±1 standard deviation). The quantum nodes and channels demonstrated here can serve as an elementary link of a quantum repeater. Moreover, the wideband absorptive quantum memories used in the nodes are compatible with deterministic entanglement sources and can simultaneously support multiplexing, which paves the way for the construction of practical solid-state quantum repeaters and high-speed quantum networks.

5.
Blood ; 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38958479

RESUMEN

This study aimed to compare the efficacy and safety of eltrombopag plus diacerein vs. eltrombopag alone in patients with primary immune thrombocytopenia (ITP) who were previously unresponsive to 14 days of eltrombopag treatment at the full dose. Recruited patients were randomly assigned 1:1 to receive either eltrombopag plus diacerein (n=50) or eltrombopag monotherapy (n=52). Overall response rate, defined as a platelet count at or above 30×109/L, at least doubling of the baseline platelet count, and no bleeding, was reached in 44% of patients in the eltrombopag plus diacerein group compared with 13% in the eltrombopag group at day 15 (P = .0009), and reached in 42% of patients in the combination group compared with 12% in the monotherapy group at day 28 (P = .0006). The addition of diacerein to eltrombopag also led to a longer duration of response (P = .0004). The two most common treatment-emergent adverse events were respiratory infection and gastrointestinal reactions in the combination group, and fatigue and respiratory infection in the eltrombopag group. In conclusion, eltrombopag plus diacerein was well tolerated, and induced higher overall response rates and longer duration of response than eltrombopag alone, offering a rejuvenating salvage therapy for ITP patients unresponsive to 14 days of full dosage eltrombopag. Our work has the potential to enhance the care of patients treated with thrombopoietin receptor agonists, reducing the need for rapid transitions to less-preferable therapies. This study is registered at ClinicalTrials.gov as NCT04917679.

6.
Blood ; 144(1): 99-112, 2024 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-38574321

RESUMEN

ABSTRACT: Platelet α-granules are rich in transforming growth factor ß1 (TGF-ß1), which is associated with myeloid-derived suppressor cell (MDSC) biology. Responders to thrombopoietin receptor agonists (TPO-RAs) revealed a parallel increase in the number of both platelets and MDSCs. Here, anti-CD61 immune-sensitized splenocytes were transferred into severe combined immunodeficient mice to establish an active murine model of immune thrombocytopenia (ITP). Subsequently, we demonstrated that TPO-RAs augmented the inhibitory activities of MDSCs by arresting plasma cells differentiation, reducing Fas ligand expression on cytotoxic T cells, and rebalancing T-cell subsets. Mechanistically, transcriptome analysis confirmed the participation of TGF-ß/Smad pathways in TPO-RA-corrected MDSCs, which was offset by Smad2/3 knockdown. In platelet TGF-ß1-deficient mice, TPO-RA-induced amplification and enhanced suppressive capacity of MDSCs was waived. Furthermore, our retrospective data revealed that patients with ITP achieving complete platelet response showed superior long-term outcomes compared with those who only reach partial response. In conclusion, we demonstrate that platelet TGF-ß1 induces the expansion and functional reprogramming of MDSCs via the TGF-ß/Smad pathway. These data indicate that platelet recovery not only serves as an end point of treatment response but also paves the way for immune homeostasis in immune-mediated thrombocytopenia.


Asunto(s)
Plaquetas , Células Supresoras de Origen Mieloide , Púrpura Trombocitopénica Idiopática , Factor de Crecimiento Transformador beta1 , Animales , Factor de Crecimiento Transformador beta1/metabolismo , Células Supresoras de Origen Mieloide/metabolismo , Células Supresoras de Origen Mieloide/inmunología , Plaquetas/metabolismo , Plaquetas/inmunología , Ratones , Púrpura Trombocitopénica Idiopática/inmunología , Púrpura Trombocitopénica Idiopática/patología , Púrpura Trombocitopénica Idiopática/metabolismo , Humanos , Femenino , Masculino , Ratones SCID , Transducción de Señal , Reprogramación Celular , Adulto
7.
J Immunol ; 212(7): 1188-1195, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38391298

RESUMEN

STING-mediated DNA sensing pathway plays a crucial role in the innate antiviral immune responses. Clarifying its regulatory mechanism and searching STING agonists has potential clinical implications. Although multiple STING agonists have been developed to target cancer, there are few for the treatment of infectious diseases. Astaxanthin, a natural and powerful antioxidant, serves many biological functions and as a potential candidate drug for many diseases. However, how astaxanthin combats viruses and whether astaxanthin regulates the cyclic GMP-AMP synthase-STING pathway remains unclear. In this study, we showed that astaxanthin markedly inhibited HSV-1-induced lipid peroxidation and inflammatory responses and enhanced the induction of type I IFN in C57BL/6J mice and mouse primary peritoneal macrophages. Mechanistically, astaxanthin inhibited HSV-1 infection and oxidative stress-induced STING carbonylation and consequently promoted STING translocation to the Golgi apparatus and oligomerization, which activated STING-dependent host defenses. Thus, our study reveals that astaxanthin displays a strong antiviral activity by targeting STING, suggesting that astaxanthin might be a promising STING agonist and a therapeutic target for viral infectious diseases.


Asunto(s)
Virosis , Xantófilas , Animales , Ratones , Herpes Simple/tratamiento farmacológico , Inmunidad Innata , Proteínas de la Membrana/metabolismo , Ratones Endogámicos C57BL , Nucleotidiltransferasas/metabolismo , Xantófilas/farmacología , Xantófilas/uso terapéutico , Virosis/tratamiento farmacológico
8.
Plant J ; 117(3): 924-943, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37902994

RESUMEN

Chromoplasts act as a metabolic sink for carotenoids, in which plastoglobules serve as versatile lipoprotein particles. PGs in chloroplasts have been characterized. However, the features of PGs from non-photosynthetic plastids are poorly understood. We found that the development of chromoplast plastoglobules (CPGs) in globular and crystalloid chromoplasts of citrus is associated with alterations in carotenoid storage. Using Nycodenz density gradient ultracentrifugation, an efficient protocol for isolating highly purified CPGs from sweet orange (Citrus sinensis) pulp was established. Forty-four proteins were defined as likely comprise the core proteome of CPGs using comparative proteomics analysis. Lipidome analysis of different chromoplast microcompartments revealed that the nonpolar microenvironment within CPGs was modified by 35 triacylglycerides, two sitosterol esters, and one stigmasterol ester. Manipulation of the CPG-localized gene CsELT1 (esterase/lipase/thioesterase) in citrus calli resulted in increased lipids and carotenoids, which is further evidence that the nonpolar microenvironment of CPGs contributes to carotenoid accumulation and storage in the chromoplasts. This multi-feature analysis of CPGs sheds new light on the role of chromoplasts in carotenoid metabolism, paving the way for manipulating carotenoid content in citrus fruit and other crops.


Asunto(s)
Citrus sinensis , Citrus , Citrus/genética , Citrus/metabolismo , Multiómica , Carotenoides/metabolismo , Plastidios/metabolismo , Citrus sinensis/genética , Frutas/genética , Frutas/metabolismo
9.
Eur Heart J ; 45(9): 688-703, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38152853

RESUMEN

BACKGROUND AND AIMS: Anti-hypertensive agents are one of the most frequently used drugs worldwide. However, no blood pressure-lowering strategy is superior to placebo with respect to survival in diabetic hypertensive patients. Previous findings show that Wnt co-receptors LDL receptor-related proteins 5 and 6 (LRP5/6) can directly bind to several G protein-coupled receptors (GPCRs). Because angiotensin II type 1 receptor (AT1R) is the most important GPCR in regulating hypertension, this study examines the possible mechanistic association between LRP5/6 and their binding protein Dickkopf-1 (DKK1) and activation of the AT1R and further hypothesizes that the LRP5/6-GPCR interaction may affect hypertension and potentiate cardiac impairment in the setting of diabetes. METHODS: The roles of serum DKK1 and DKK1-LRP5/6 signalling in diabetic injuries were investigated in human and diabetic mice. RESULTS: Blood pressure up-regulation positively correlated with serum DKK1 elevations in humans. Notably, LRP5/6 physically and functionally interacted with AT1R. The loss of membrane LRP5/6 caused by injection of a recombinant DKK1 protein or conditional LRP5/6 deletions resulted in AT1R activation and hypertension, as well as ß-arrestin1 activation and cardiac impairment, possibly because of multiple GPCR alterations. Importantly, unlike commonly used anti-hypertensive agents, administration of the anti-DKK1 neutralizing antibody effectively prevented diabetic cardiac impairment in mice. CONCLUSIONS: These findings establish a novel DKK1-LRP5/6-GPCR pathway in inducing diabetic injuries and may resolve the long-standing conundrum as to why elevated blood DKK1 has deleterious effects. Thus, monitoring and therapeutic elimination of blood DKK1 may be a promising strategy to attenuate diabetic injuries.


Asunto(s)
Diabetes Mellitus Experimental , Cardiomiopatías Diabéticas , Hipertensión , Receptores de LDL , Animales , Humanos , Ratones , Antihipertensivos , Cardiomiopatías Diabéticas/prevención & control , Hipertensión/prevención & control , Receptores de LDL/antagonistas & inhibidores
10.
Chem Soc Rev ; 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38953906

RESUMEN

High-quality transparent electrodes are indispensable components of flexible optoelectronic devices as they guarantee sufficient light transparency and electrical conductivity. Compared to commercial indium tin oxide, metal nanowires are considered ideal candidates as flexible transparent electrodes (FTEs) owing to their superior optoelectronic properties, excellent mechanical flexibility, solution treatability, and higher compatibility with semiconductors. However, certain key challenges associated with material preparation and device fabrication remain for the practical application of metal nanowire-based electrodes. In this review, we discuss state-of-the-art solution-processed metal nanowire-based FTEs and their applications in flexible and stretchable optoelectronic devices. Specifically, the important properties of FTEs and a cost-benefit analysis of existing technologies are introduced, followed by a summary of the synthesis strategy, key properties, and fabrication technologies of the nanowires. Subsequently, we explore the applications of metal-nanowire-based FTEs in different optoelectronic devices including solar cells, photodetectors, and light-emitting diodes. Finally, the current status, future challenges, and emerging strategies in this field are presented.

11.
Am J Physiol Cell Physiol ; 327(1): C65-C73, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38766766

RESUMEN

The blood-brain barrier (BBB) plays a critical role in the development and outcome of subarachnoid hemorrhage (SAH). This study focuses on the potential mechanism by which G-protein-coupled estrogen receptor 30 (GPR30) affects the BBB after SAH. A rat SAH model was established using an intravascular perforation approach. G1 (GPR30 agonist) was administered to investigate the mechanism of BBB damage after SAH. Brain water content, Western blotting, Evans blue leakage, and immunofluorescence staining were performed. Brain microvascular endothelial cells were induced by hemin to establish SAH model in vitro. By adding LY294002 [a phosphatidylinositol 3-kinase (PI3K) blocker] and zinc protoporphyrin IX (ZnPP IX) [a heme oxygenase 1 (HO-1) antagonist], the mechanism of improving BBB integrity through the activation of GPR30 was studied. In vivo, GPR30 activation improved BBB disruption, as evidenced by decreased cerebral edema, downregulated albumin expression, and reduced extravasation of Evans blue and IgG after G1 administration in SAH rats. Moreover, SAH downregulated the levels of tight junction (TJ) proteins, whereas treatment with G1 reversed the effect of SAH. The protective effect of G1 on BBB integrity in vitro was consistent with that in vivo, as evidenced by G1 reducing the impact of hemin on transendothelial electrical resistance (TEER) value, dextran diffusivity, and TJ protein levels in brain microvascular endothelial cells. In addition, G1 activated the PI3K/ protein kinase B (Akt) and nuclear factor erythroid 2-related factor 2 (Nrf2)/HO-1 pathways both in vivo and in vitro. Furthermore, the administration of LY294002 and ZnPP IX partially reversed the protective effect of G1 on BBB integrity in hemin-stimulated cells. We demonstrated that the activation of GPR30, at least partly through the PI3K/Akt and Nrf2/HO-1 pathways, alleviated BBB damage both in vivo and in vitro. This study introduced a novel therapeutic approach for protecting the BBB after SAH.NEW & NOTEWORTHY The PI3K/Akt and Nrf2/HO-1 pathways might be potential mechanisms by which GPR30 protected the integrity of the BBB in SAH models. Therefore, treatment of SAH with GPR30 activator might be a promising therapeutic strategy.


Asunto(s)
Barrera Hematoencefálica , Factor 2 Relacionado con NF-E2 , Fosfatidilinositol 3-Quinasas , Proteínas Proto-Oncogénicas c-akt , Ratas Sprague-Dawley , Receptores Acoplados a Proteínas G , Transducción de Señal , Hemorragia Subaracnoidea , Animales , Factor 2 Relacionado con NF-E2/metabolismo , Barrera Hematoencefálica/metabolismo , Barrera Hematoencefálica/efectos de los fármacos , Barrera Hematoencefálica/patología , Proteínas Proto-Oncogénicas c-akt/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Receptores Acoplados a Proteínas G/agonistas , Hemorragia Subaracnoidea/metabolismo , Hemorragia Subaracnoidea/patología , Hemorragia Subaracnoidea/tratamiento farmacológico , Hemorragia Subaracnoidea/complicaciones , Masculino , Ratas , Fosfatidilinositol 3-Quinasas/metabolismo , Células Endoteliales/metabolismo , Células Endoteliales/efectos de los fármacos , Hemo Oxigenasa (Desciclizante)/metabolismo , Hemo-Oxigenasa 1/metabolismo , Modelos Animales de Enfermedad , Fosfatidilinositol 3-Quinasa/metabolismo , Hemina/farmacología
12.
J Cell Mol Med ; 28(9): e18321, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38712979

RESUMEN

As a main extraction compound from Scutellaria baicalensis Georgi, Baicalin exhibits various biological activities. However, the underlying mechanism of Baicalin on hypertension-induced heart injury remains unclear. In vivo, mice were infused with angiotensin II (Ang II; 500 ng/kg/min) or saline using osmotic pumps, followed by intragastrically administrated with Baicalin (5 mg/kg/day) for 4 weeks. In vitro, H9C2 cells were stimulated with Ang II (1 µM) and treated with Baicalin (12.5, 25 and 50 µM). Baicalin treatment significantly attenuated the decrease in left ventricular ejection fraction and left ventricular fractional shortening, increase in left ventricular mass, left ventricular systolic volume and left ventricular diastolic volume of Ang II infused mice. Moreover, Baicalin treatment reversed 314 differentially expressed transcripts in the cardiac tissues of Ang II infused mice, and enriched multiple enriched signalling pathways (including apoptosis, autophagy, AMPK/mTOR signalling pathway). Consistently, Baicalin treatment significantly alleviated Ang II-induced cell apoptosis in vivo and in vitro. Baicalin treatment reversed the up-regulation of Bax, cleaved-caspase 3, cleaved-caspase 9, and the down-regulation of Bcl-2. Meanwhile, Baicalin treatment alleviated Ang II-induced increase of autophagosomes, restored autophagic flux, and down-regulated LC3II, Beclin 1, as well as up-regulated SQSTM1/p62 expression. Furthermore, autophagy inhibitor 3-methyladenine treatment alleviated the increase of autophagosomes and the up-regulation of Beclin 1, LC3II, Bax, cleaved-caspase 3, cleaved-caspase 9, down-regulation of SQSTM1/p62 and Bcl-2 expression after Ang II treated, which similar to co-treatment with Baicalin. Baicalin treatment reduced the ratio of p-AMPK/AMPK, while increased the ratio of p-mTOR/mTOR. Baicalin alleviated Ang II-induced cardiomyocyte apoptosis and autophagy, which might be related to the inhibition of the AMPK/mTOR pathway.


Asunto(s)
Angiotensina II , Apoptosis , Autofagia , Flavonoides , Miocitos Cardíacos , Transducción de Señal , Animales , Masculino , Ratones , Ratas , Proteínas Quinasas Activadas por AMP/metabolismo , Angiotensina II/metabolismo , Apoptosis/efectos de los fármacos , Autofagia/efectos de los fármacos , Línea Celular , Flavonoides/farmacología , Ratones Endogámicos C57BL , Miocitos Cardíacos/efectos de los fármacos , Miocitos Cardíacos/metabolismo , Miocitos Cardíacos/patología , Transducción de Señal/efectos de los fármacos , Serina-Treonina Quinasas TOR/metabolismo
13.
BMC Plant Biol ; 24(1): 392, 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38735932

RESUMEN

BACKGROUND: Long-chain acyl-coenzyme A synthetase (LACS) is a type of acylating enzyme with AMP-binding, playing an important role in the growth, development, and stress response processes of plants. RESULTS: The research team identified different numbers of LACS in four cotton species (Gossypium hirsutum, Gossypium barbadense, Gossypium raimondii, and Gossypium arboreum). By analyzing the structure and evolutionary characteristics of the LACS, the GhLACS were divided into six subgroups, and a chromosome distribution map of the family members was drawn, providing a basis for further research classification and positioning. Promoter cis-acting element analysis showed that most GhLACS contain plant hormones (GA, MeJA) or non-biological stress-related cis-elements. The expression patterns of GhLACS under salt stress treatment were analyzed, and the results showed that GhLACS may significantly participate in salt stress response through different mechanisms. The research team selected 12 GhLACSs responsive to salt stress for tissue expression analysis and found that these genes are expressed in different tissues. CONCLUSIONS: There is a certain diversity of LACS among different cotton species. Analysis of promoter cis-acting elements suggests that GhLACS may be involved in regulating plant growth, development and stress response processes. GhLACS25 was selected for in-depth study, which confirmed its significant role in salt stress response through virus-induced gene silencing (VIGS) and induced expression in yeast cells.


Asunto(s)
Gossypium , Proteínas de Plantas , Estrés Salino , Gossypium/genética , Gossypium/fisiología , Estrés Salino/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regulación de la Expresión Génica de las Plantas , Coenzima A Ligasas/genética , Coenzima A Ligasas/metabolismo , Familia de Multigenes , Filogenia , Regiones Promotoras Genéticas/genética , Genoma de Planta , Genes de Plantas
14.
Blood ; 140(26): 2818-2834, 2022 12 29.
Artículo en Inglés | MEDLINE | ID: mdl-36037415

RESUMEN

Myeloid-derived suppressor cells (MDSCs) are heterogeneous immature cells and natural inhibitors of adaptive immunity. Metabolic fitness of MDSCs is fundamental for its suppressive activity toward effector T cells. Our previous studies showed that the number and inhibitory function of MDSCs were impaired in patients with immune thrombocytopenia (ITP) compared with healthy controls. In this study, we analyzed the effects of decitabine on MDSCs from patients with ITP, both in vitro and in vivo. We found that low-dose decitabine promoted the generation of MDSCs and enhanced their aerobic metabolism and immunosuppressive functions. Lower expression of liver kinase 1 (LKB1) was found in MDSCs from patients with ITP, which was corrected by decitabine therapy. LKB1 short hairpin RNA (shRNA) transfection effectively blocked the function of MDSCs and almost offset the enhanced effect of decitabine on impaired MDSCs. Subsequently, anti-CD61 immune-sensitized splenocytes were transferred into severe combined immunodeficient (SCID) mice to induce ITP in murine models. Passive transfer of decitabine-modulated MDSCs significantly raised platelet counts compared with that of phosphate buffered saline-modulated MDSCs. However, when LKB1 shRNA-transfected MDSCs were transferred into SCID mice, the therapeutic effect of decitabine in alleviating thrombocytopenia was quenched. In conclusion, our study suggests that the impaired aerobic metabolism of MDSCs is involved in the pathogenesis of ITP, and the modulatory effect of decitabine on MDSC metabolism contributes to the improvement of its immunosuppressive function. This provides a possible mechanism for sustained remission elicited by low-dose decitabine in patients with ITP.


Asunto(s)
Células Supresoras de Origen Mieloide , Púrpura Trombocitopénica Idiopática , Trombocitopenia , Animales , Ratones , Decitabina/farmacología , Decitabina/uso terapéutico , Ratones SCID , Trombocitopenia/metabolismo , Hígado
15.
Opt Express ; 32(10): 17657-17666, 2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38858943

RESUMEN

Tin diselenide (SnSe2), a layered transition metal dichalcogenide (TMDC), stands out among other TMDCs for its extraordinary photoactive ability and low thermal conductivity. Consequently, it has stimulated many influential researches on photodetectors, ultrafast pulse shaping, thermoelectric devices, etc. However, the carrier mobility in SnSe2, as determined experimentally, remains limited to tens of cm2V-1s-1. This limitation poses a challenge for achieving high-performance SnSe2-based devices. Theoretical calculations, on the other hand, predict that the carrier mobility in SnSe2 can reach hundreds of cm2V-1s-1, approximately one order of magnitude higher than experimental value. Interestingly, the carrier mobility could be underestimated significantly in long-range transportation measurements due to the presence of defects and boundary scattering effects. To address this discrepancy, we employ optic pump terahertz probe spectroscopy to access the photoinduced dynamical THz photoconductivity of SnSe2. Our findings reveal that the intrinsic carrier mobility in conventional SnSe2 single crystal is remarkably high, reaching 353.2 ± 37.7 cm2V-1s-1, consistent with the theoretical prediction. Additionally, dynamical THz photoconductivity measurements reveal that the SnSe2 crystal containing rich defects efficiently capture photoinduced conduction-band electrons and valence-band holes with time constants of ∼20 and ∼200 ps, respectively. Meanwhile, we observe an impulsively stimulated Raman scattering at 0.60 THz. Our study not only demonstrates ultrafast THz spectroscopy as a reliable method for determining intrinsic carrier mobility and detection of low frequency coherent Raman mode in materials but also provides valuable reference for the future application of high-performance SnSe2-based devices.

16.
Cardiovasc Diabetol ; 23(1): 150, 2024 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-38702777

RESUMEN

BACKGROUND: Vasculopathy is the most common complication of diabetes. Endothelial cells located in the innermost layer of blood vessels are constantly affected by blood flow or vascular components; thus, their mechanosensitivity plays an important role in mediating vascular regulation. Endothelial damage, one of the main causes of hyperglycemic vascular complications, has been extensively studied. However, the role of mechanosensitive signaling in hyperglycemic endothelial damage remains unclear. METHODS: Vascular endothelial-specific Piezo1 knockout mice were generated to investigate the effects of Piezo1 on Streptozotocin-induced hyperglycemia and vascular endothelial injury. In vitro activation or knockdown of Piezo1 was performed to evaluate the effects on the proliferation, migration, and tubular function of human umbilical vein endothelial cells in high glucose. Reactive oxygen species production, mitochondrial membrane potential alternations, and oxidative stress-related products were used to assess the extent of oxidative stress damage caused by Piezo1 activation. RESULTS: Our study found that in VECreERT2;Piezo1flox/flox mice with Piezo1 conditional knockout in vascular endothelial cells, Piezo1 deficiency alleviated streptozotocin-induced hyperglycemia with reduced apoptosis and abscission of thoracic aortic endothelial cells, and decreased the inflammatory response of aortic tissue caused by high glucose. Moreover, the knockout of Piezo1 showed a thinner thoracic aortic wall, reduced tunica media damage, and increased endothelial nitric oxide synthase expression in transgenic mice, indicating the relief of endothelial damage caused by hyperglycemia. We also showed that Piezo1 activation aggravated oxidative stress injury and resulted in severe dysfunction through the Ca2+-induced CaMKII-Nrf2 axis in human umbilical vein endothelial cells. In Piezo1 conditional knockout mice, Piezo1 deficiency partially restored superoxide dismutase activity and reduced malondialdehyde content in the thoracic aorta. Mechanistically, Piezo1 deficiency decreased CaMKII phosphorylation and restored the expression of Nrf2 and its downstream molecules HO-1 and NQO1. CONCLUSION: In summary, our study revealed that Piezo1 is involved in high glucose-induced oxidative stress injury and aggravated endothelial dysfunction, which have great significance for alleviating endothelial damage caused by hyperglycemia.


Asunto(s)
Glucemia , Diabetes Mellitus Experimental , Células Endoteliales de la Vena Umbilical Humana , Canales Iónicos , Ratones Noqueados , Óxido Nítrico Sintasa de Tipo III , Estrés Oxidativo , Animales , Humanos , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Células Endoteliales de la Vena Umbilical Humana/patología , Diabetes Mellitus Experimental/metabolismo , Canales Iónicos/metabolismo , Canales Iónicos/genética , Glucemia/metabolismo , Óxido Nítrico Sintasa de Tipo III/metabolismo , Mecanotransducción Celular , Factor 2 Relacionado con NF-E2/metabolismo , Factor 2 Relacionado con NF-E2/genética , Factor 2 Relacionado con NF-E2/deficiencia , Células Cultivadas , Proliferación Celular , Apoptosis , Masculino , Angiopatías Diabéticas/metabolismo , Angiopatías Diabéticas/fisiopatología , Angiopatías Diabéticas/patología , Angiopatías Diabéticas/genética , Angiopatías Diabéticas/etiología , Movimiento Celular , Ratones Endogámicos C57BL , Especies Reactivas de Oxígeno/metabolismo , Aorta Torácica/metabolismo , Aorta Torácica/patología , Aorta Torácica/fisiopatología , Ratones , Estreptozocina , Endotelio Vascular/metabolismo , Endotelio Vascular/fisiopatología , Endotelio Vascular/patología , Proteína Quinasa Tipo 2 Dependiente de Calcio Calmodulina/metabolismo , Proteína Quinasa Tipo 2 Dependiente de Calcio Calmodulina/genética
17.
Ann Hematol ; 103(3): 999-1005, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38285081

RESUMEN

Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare hematologic malignancy that is highly aggressive with a poor prognosis. There is no standard treatment for BPDCN. Although conventional chemotherapies are usually sensitive in the initial therapy, relapse and drug resistance are inevitable within a short duration. Targeted therapies have enlightened new prospects for the treatment of BPDCN, especially for those in a frail state and intolerable to standard chemotherapies or hematopoietic stem cell transplantation. Here, we report an 82-year-old man diagnosed with cutaneous-limited BPDCN. Considering the old age and limited involvement of the tumor, we reduced the dosage of venetoclax. His skin lesions subsided significantly after 1 cycle of azacytidine (100 mg d1-7) combined with reduced doses of venetoclax (200 mg d1-14). The reduction in the dose of venetoclax avoided severe myelosuppression while achieving satisfactory outcomes. The patient received 2 cycles of therapy with no skin lesions re-occurred for 7 months before relapsing.


Asunto(s)
Compuestos Bicíclicos Heterocíclicos con Puentes , Neoplasias Hematológicas , Trastornos Mieloproliferativos , Neoplasias Cutáneas , Sulfonamidas , Masculino , Humanos , Anciano de 80 o más Años , Azacitidina/uso terapéutico , Células Dendríticas/patología , Recurrencia Local de Neoplasia/tratamiento farmacológico , Neoplasias Cutáneas/patología , Neoplasias Hematológicas/terapia , Trastornos Mieloproliferativos/patología
18.
Neurochem Res ; 49(3): 718-731, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38063947

RESUMEN

Cerebral ischemic stroke is a cerebrovascular disease, which is related to DNA damage. Many researches have shown that Ku70 is a key regulator for DNA damage. Here, we aimed to explore Ku70 roles in cerebral ischemic stroke and its potential molecular mechanism. In our study, neural stem cells (NSCs) were induced by oxygen-glucose deprivation/reoxygenation (OGD/R) for constructing cerebral ischemic stroke cell model. CCK8 assay, Brdu/GFP staining, flow cytometry and TUNEL staining were performed to examine cell proliferation, cell cycle and apoptosis, respectively. Relative mRNA and protein levels were detected by quantitative real-time PCR and western blot analysis, respectively. Ku70 positive cells were examined by immunofluorescence staining. Comet assay was employed to determine DNA damage. Animal experiments were performed to assess the effect of transplanting NSCs and Ku70-overexpressed NSCs on neurological deficits, infarct volume, brain edema and blood‒brain barrier (BBB) integrity in middle cerebral artery occlusion (MCAO) model. Our data found that Ku70 expression was decreased in NSCs after OGD/R. Overexpression of Ku70 reduced DNA damage and apoptosis of OGD/R-induced NSCs. Knockdown of Ku70 promoted the activity of ATM/p53. Moreover, KU60019 (ATM-specific inhibitor) reversed the promoting effects of Ku70 silencing on DNA damage and apoptosis in OGD/R-induced NSCs. In animal experiments, transplantation of NSCs-overexpressed Ku70 enhanced cell survival, improved motor function, reduced infarct volume, relieved brain edema and alleviated BBB dysfunction in MCAO mice models. In conclusion, Ku70 overexpression repressed the DNA damage and apoptosis in OGD/R-induced NSCs by regulating ATM/p53 pathway, and transplantation of NSCs-overexpressed Ku70 played neuroprotective effects in MCAO mice models.


Asunto(s)
Edema Encefálico , Isquemia Encefálica , Accidente Cerebrovascular Isquémico , Células-Madre Neurales , Daño por Reperfusión , Accidente Cerebrovascular , Ratones , Animales , Edema Encefálico/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Isquemia Encefálica/metabolismo , Accidente Cerebrovascular/metabolismo , Células-Madre Neurales/metabolismo , Infarto de la Arteria Cerebral Media/terapia , Infarto de la Arteria Cerebral Media/metabolismo , Oxígeno/metabolismo , Daño por Reperfusión/metabolismo , Accidente Cerebrovascular Isquémico/metabolismo , Apoptosis
19.
Anticancer Drugs ; 35(5): 445-449, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38385995

RESUMEN

Savolitinib is a selective inhibitor that specifically targets the phosphorylation of mesenchymal-epithelial transition (MET) kinase. It has demonstrated significant inhibitory effects on the proliferation of tumor cells with METex14 skipping mutation, making it a promising treatment option. While it is the first approved small-molecule inhibitor specifically targeting MET kinase in China, there is limited information about its efficacy as neoadjuvant therapy for patients with supraclavicular lymph node metastasis (N3). In this case report, we presented the successful outcome of a 48-year-old male patient who was diagnosed with stage IIIB (T2bN3M0) lung adenocarcinoma originating from the left upper lobe. The patient exhibited the METex14 skipping alteration. Following two months of neoadjuvant savolitinib treatment, the patient achieved partial remission, with a significant reduction in the size of the primary tumor and metastatic lymph nodes. Postoperative pathological confirmation revealed a pathological complete response, and subsequent imaging examinations, including computed tomography scan and circulating tumor DNA-based molecular residual disease detection, showed no sign of recurrence at 7 months after surgery. Based on this case, neoadjuvant and adjuvant savolitinib therapy may be considered as a favorable alternative to chemotherapy for marginally resectable nonsmall cell lung cancer patients with METex14 skipping mutation.


Asunto(s)
Adenocarcinoma del Pulmón , Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Pirazinas , Triazinas , Masculino , Humanos , Persona de Mediana Edad , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Terapia Neoadyuvante , Adenocarcinoma del Pulmón/tratamiento farmacológico , Adenocarcinoma del Pulmón/genética , Mutación , Exones
20.
Pharmacol Res ; 200: 107052, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38181857

RESUMEN

BACKGROUND: The efficacy and safety of Qingda granule (QDG) in managing blood pressure (BP) among grade 1 hypertensive patients with low-moderate risk remain uncertain. METHODS: In the randomized, double-blind, double dummy, non-inferiority and multicenter trial, 552 patients with grade 1 hypertension at low-moderate risk were assigned at a ratio of 1:1 to receive either QDG or valsartan for 4 weeks, followed up by a subsequent 4 weeks. RESULTS: Post-treatment, clinic systolic/diastolic BPs (SBP/DBP) were reduced by a mean change of 9.18/4.04 mm Hg in the QDG group and 9.85/5.05 mm Hg in the valsartan group (SBP P = 0.47, DBP P = 0.16). Similarly, 24-hour, daytime and nighttime BPs were proportional in both groups (P > 0.05) after 4 weeks treatment. After discontinuing medications for 4 weeks, the mean reduction of clinic SBP/DBP were 0.29/0.57 mm Hg in the QDG group compared to -1.59/-0.48 mm Hg in the valsartan group (SBP P = 0.04, DBP P = 0.04). Simultaneously, the 24-hour SBP/DBP were reduced by 0.9/0.31 mm Hg in the QDG group and -1.66/-1.08 mm Hg in the valsartan group (SBP P = 0.006, DBP P = 0.02). And similar results were observed regarding the outcomes of daytime and nighttime BPs. There was no difference in occurrence of adverse events between two groups (P > 0.05). CONCLUSION: QDG proves to be efficacious for grade 1 hypertension at a low-to-medium risk, even after discontinuation of the medication for 4 weeks. These findings provide a promising option for managing grade 1 hypertension and suggest the potential for maintaining stable BP through intermittent administration of QDG. TRIAL REGISTRATION: ChiCTR2000033890.


Asunto(s)
Antihipertensivos , Medicamentos Herbarios Chinos , Hipertensión , Humanos , Antihipertensivos/efectos adversos , Presión Sanguínea , China , Método Doble Ciego , Tetrazoles/efectos adversos , Valsartán/efectos adversos
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