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1.
Plant Cell ; 35(1): 598-616, 2023 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-36269178

RESUMEN

RNA-binding proteins (RBPs) participate in a diverse set of biological processes in plants, but their functions and underlying mechanisms in plant-pathogen interactions are largely unknown. We previously showed that Arabidopsis thaliana BPA1-LIKE PROTEIN3 (BPL3) belongs to a conserved plant RBP family and negatively regulates reactive oxygen species (ROS) accumulation and cell death under biotic stress. In this study, we demonstrate that BPL3 suppresses FORKED-LIKE7 (FL7) transcript accumulation and raises levels of the cis-natural antisense long non-coding RNA (lncRNA) of FL7 (nalncFL7). FL7 positively regulated plant immunity to Phytophthora capsici while nalncFL7 negatively regulated resistance. We also showed that BPL3 directly binds to and stabilizes nalncFL7. Moreover, nalncFL7 suppressed accumulation of FL7 transcripts. Furthermore, FL7 interacted with HIGHLY ABA-INDUCED PP2C1 (HAI1), a type 2C protein phosphatase, and inhibited HAI1 phosphatase activity. By suppressing HAI1 activity, FL7 increased the phosphorylation levels of MITOGEN-ACTIVATED PROTEIN KINASE 3 (MPK3) and MPK6, thus enhancing immunity responses. BPL3 and FL7 are conserved in all plant species tested, but the BPL3-nalncFL7-FL7 cascade was specific to the Brassicaceae. Thus, we identified a conserved BPL3-nalncFL7-FL7 cascade that coordinates plant immunity.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Inmunidad de la Planta , ARN Largo no Codificante , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Regulación de la Expresión Génica de las Plantas/genética , Proteína Quinasa 3 Activada por Mitógenos/genética , Proteína Quinasa 3 Activada por Mitógenos/metabolismo , Quinasas de Proteína Quinasa Activadas por Mitógenos/metabolismo , Inmunidad de la Planta/genética , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo
2.
Chem Soc Rev ; 53(18): 9133-9189, 2024 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-39129564

RESUMEN

Apoptosis, as type I cell death, is an active death process strictly controlled by multiple genes, and plays a significant role in regulating various activities. Mounting research indicates that the unique modality of cell apoptosis is directly or indirectly related to different diseases including cancer, autoimmune diseases, viral diseases, neurodegenerative diseases, etc. However, the underlying mechanisms of cell apoptosis are complicated and not fully clarified yet, possibly due to the lack of effective chemical tools for the nondestructive and real-time visualization of apoptosis in complex biological systems. In the past 15 years, various small-molecule fluorescent probes (SMFPs) for imaging apoptosis in vitro and in vivo have attracted broad interest in related disease diagnostics and therapeutics. In this review, we aim to highlight the recent developments of SMFPs based on enzyme activity, plasma membranes, reactive oxygen species, reactive sulfur species, microenvironments and others during cell apoptosis. In particular, we generalize the mechanisms commonly used to design SMFPs for studying apoptosis. In addition, we discuss the limitations of reported probes, and emphasize the potential challenges and prospects in the future. We believe that this review will provide a comprehensive summary and challenging direction for the development of SMFPs in apoptosis related fields.


Asunto(s)
Apoptosis , Colorantes Fluorescentes , Colorantes Fluorescentes/química , Humanos , Animales , Especies Reactivas de Oxígeno/metabolismo , Especies Reactivas de Oxígeno/análisis , Bibliotecas de Moléculas Pequeñas/química , Imagen Óptica
3.
Nano Lett ; 24(29): 8988-8995, 2024 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-38985015

RESUMEN

Exciton-polaritons, hybrid quasiparticles from the strong coupling of excitons and cavity photons in semiconductor microcavities, offer a platform for exploring quantum coherence and nonlinear optical properties. The unique polariton parametric scattering (PPS) laser is of interest for its potential in quantum technologies and nonlinear devices. However, direct resonant excitation of polaritons in strong-coupling microcavities is challenging. This study proposes an innovative two-photon absorption (TPA) pump mechanism to address this. We observe TPA-driven PPS lasing in a strongly coupled microcavity at room temperature. High K-value exciton injections promote coherent stimulated emission of polariton scattering through intermode channels. Angle-resolved spectra confirm a TPA process, showing evolution from pump-state to signal-state. Hanbury Brown-Twiss measurement of second-order correlation g2(τ) of signal state indicates a phase transition from a classical thermal state to a quantum coherent state. Theoretical modeling provides insights into the physical mechanisms of PPS. Our work advances nonlinear phenomena exploration in strongly coupled light-matter systems, contributing to quantum polaritonics and nonlinear optics.

4.
Lancet Oncol ; 25(7): 901-911, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38823410

RESUMEN

BACKGROUND: Antibody-drug conjugates have promising clinical activity in the treatment of solid tumours. BL-B01D1 is a first-in-class EGFR-HER3 bispecific antibody-drug conjugate. We aimed to assess the safety and preliminary antitumour activity of BL-B01D1 in patients with locally advanced or metastatic solid tumours. METHODS: This first-in-human, open-label, multicentre, dose-escalation and dose-expansion phase 1 trial was conducted in seven hospitals in China, enrolling patients aged 18-75 years (dose escalation; phase 1a) or older than 18 years (dose expansion; phase 1b), with a life expectancy of at least 3 months, an Eastern Cooperative Oncology Group performance status of 0-1, and histologically or cytologically confirmed locally advanced or metastatic solid tumours that had progressed on current standard treatment. In the phase 1a i3+3 design, patients received intravenous BL-B01D1 at three different schedules: 0·27 mg/kg, 1·5 mg/kg, and 3·0 mg/kg weekly; 2·5 mg/kg, 3·0 mg/kg, and 3·5 mg/kg on days 1 and 8 of each cycle every 3 weeks; or 5·0 mg/kg and 6·0 mg/kg on day 1 of each cycle every 3 weeks. The primary objectives of phase 1a were to identify the safety, maximum tolerated dose, and dose-limiting toxicity. In phase 1b, patients were treated in two schedules: 2·5 and 3·0 mg/kg on days 1 and 8 every 3 weeks, or 4·5, 5·0, and 6·0 mg/kg on day 1 every 3 weeks. The primary objectives of phase 1b were to assess the safety and recommended phase 2 dose of BL-B01D1, and objective response rate was a key secondary endpoint. Safety was analysed in all patients with safety records who received at least one dose of BL-B01D1. Antitumour activity was assessed in the activity analysis set which included all patients who received at least one dose of BL-B01D1 every 3 weeks. This trial is registered with China Drug Trials, CTR20212923, and ClinicalTrials.gov, NCT05194982, and recruitment is ongoing. FINDINGS: Between Dec 8, 2021, and March 13, 2023, 195 patients (133 [65%] men and 62 [32%] women; 25 in phase 1a and 170 in phase 1b) were consecutively enrolled, including 113 with non-small-cell lung cancer, 42 with nasopharyngeal carcinomas, 13 with small-cell lung cancer, 25 with head and neck squamous cell carcinoma, one with thymic squamous cell carcinoma, and one with submandibular lymphoepithelioma-like carcinoma. In phase 1a, four dose-limiting toxicities were observed (two at 3·0 mg/kg weekly and two at 3·5 mg/kg on days 1 and 8 every 3 weeks; all were febrile neutropenia), thus the maximum tolerated dose was reached at 3·0 mg/kg on days 1 and 8 every 3 weeks and 6·0 mg/kg on day 1 every 3 weeks. Grade 3 or worse treatment-related adverse events occurred in 139 (71%) of 195 patients; the most common of which were neutropenia (91 [47%]), anaemia (76 [39%]), leukopenia (76 [39%]), and thrombocytopenia (63 [32%]). 52 (27%) patients had a dose reduction and five (3%) patients discontinued treatment due to treatment-related adverse events. One patient was reported as having interstitial lung disease. Treatment-related deaths occurred in three (2%) patients (one due to pneumonia, one due to septic shock, and one due to myelosuppression). In 174 patients evaluated for activity, median follow-up was 6·9 months (IQR 4·5-8·9) and 60 (34%; 95% CI 27-42) patients had an objective response. INTERPRETATION: Our results suggest that BL-B01D1 has preliminary antitumour activity in extensively and heavily treated advanced solid tumours with an acceptable safety profile. Based on the safety and antitumour activity data from both phase 1a and 1b, 2·5 mg/kg on days 1 and 8 every 3 weeks was selected as the recommended phase 2 dose in Chinese patients. FUNDING: Sichuan Baili Pharmaceutical. TRANSLATION: For the Chinese translation of the abstract see Supplementary Materials section.


Asunto(s)
Anticuerpos Biespecíficos , Receptores ErbB , Inmunoconjugados , Neoplasias , Receptor ErbB-3 , Humanos , Persona de Mediana Edad , Masculino , Femenino , Anticuerpos Biespecíficos/administración & dosificación , Anticuerpos Biespecíficos/efectos adversos , Anticuerpos Biespecíficos/uso terapéutico , Anciano , Adulto , Neoplasias/tratamiento farmacológico , Neoplasias/patología , Inmunoconjugados/administración & dosificación , Inmunoconjugados/efectos adversos , Inmunoconjugados/uso terapéutico , Receptores ErbB/antagonistas & inhibidores , Receptores ErbB/inmunología , Receptor ErbB-3/antagonistas & inhibidores , Receptor ErbB-3/inmunología , Adulto Joven , Dosis Máxima Tolerada , Adolescente , Metástasis de la Neoplasia , China , Antineoplásicos Inmunológicos/administración & dosificación , Antineoplásicos Inmunológicos/efectos adversos , Antineoplásicos Inmunológicos/uso terapéutico
5.
Anal Chem ; 96(5): 2264-2272, 2024 02 06.
Artículo en Inglés | MEDLINE | ID: mdl-38266388

RESUMEN

Lipid metabolism diseases have become a tremendous risk worldwide, along with the development of productivity and particular attention to public health. It has been an urgent necessity to exploit reliable imaging strategies for lipids and thus to monitor fatty liver diseases. Herein, by converting the NIR-I signal to the NIR-II signal with IR1061 for the monitoring of lipid, the in vivo imaging of fatty liver disease was promoted on the contrast and visual effect. The main advantages of the imaging promotion in this work included a long emission wavelength, rapid response, and high signal-background-ratio (SBR) value. After promoting the NIR-I signal to NIR-II signal, IR1061 achieved higher SBR value and exhibited a dose-dependent fluorescence intensity at 1100 nm along with the increase of the EtOH proportion as well as steady and selective optical responses toward liposomes. IR1061 was further applied in the in vivo imaging of lipid in fatty liver diseases. In spite of the differences in body weight gain and TC level between healthy mice and fatty liver diseases two models, IR1061 achieved high-resolution imaging in the liver region to monitor the fatty liver disease status. This work might be informatic for the clinical diagnosis and therapeutical treatments of fatty liver diseases.


Asunto(s)
Boratos , Metabolismo de los Lípidos , Hepatopatías , Piranos , Animales , Ratones , Imagen Óptica/métodos , Colorantes Fluorescentes , Lípidos
6.
Anal Chem ; 96(18): 7005-7013, 2024 05 07.
Artículo en Inglés | MEDLINE | ID: mdl-38657082

RESUMEN

Hydrogen sulfide (H2S), a critical gas signaling molecule, and N-acetyltransferase 2 (NAT2), a key enzyme in drug metabolism, are both known active biomarkers for liver function. However, the interactions and effects of H2S and NAT2 in living cells or lesion sites remain unknown due to the lack of imaging tools to achieve simultaneous detection of these two substances, making it challenging to implement real-time imaging and precise tracking. Herein, we report an activity-based two-photon fluorescent probe, TPSP-1, for the cascade detection of H2S and NAT2 in living liver cells. Continuous conversion from TPSP-1 to TPSP-3 was achieved in liver cells and tissues. Significantly, leveraging the outstanding optical properties of this two-photon fluorescent probe, TPSP-1, has been effectively used to identify pathological tissue samples directly from clinical liver cancer patients. This work provides us with this novel sensing and two-photon imaging probe, which can be used as a powerful tool to study the physiological functions of H2S and NAT2 and will help facilitate rapid and accurate diagnosis and therapeutic evaluation of hepatocellular carcinoma.


Asunto(s)
Arilamina N-Acetiltransferasa , Carcinoma Hepatocelular , Colorantes Fluorescentes , Sulfuro de Hidrógeno , Neoplasias Hepáticas , Fotones , Sulfuro de Hidrógeno/análisis , Sulfuro de Hidrógeno/metabolismo , Colorantes Fluorescentes/química , Colorantes Fluorescentes/síntesis química , Humanos , Arilamina N-Acetiltransferasa/metabolismo , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patología , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/diagnóstico por imagen , Neoplasias Hepáticas/patología , Animales , Ratones , Células Hep G2 , Imagen Óptica
7.
Small ; 20(2): e2305797, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37658501

RESUMEN

Lithium metal is considered as a promising anode material for next generation lithium-based batteries due to its highest specific capacity and lowest reduction potential. However, irreversible lithium stripping/depositing gives rise to severe dendritic growth and countless dead lithium, which lead to rapid electrochemical performance degradation and increased safety hazards, and thus limit its large-scale application. Herein, this work demonstrates a universal hydrogen-bond-induced strategy to in situ form a highly polarized ferroelectric polyvinylidene fluoride (PVDF) coating on the anode current collector. The localized electric field induced by the polarized ferroelectric PVDF can accelerate the migration of lithium ions and alleviate the shortage of lithium ions and uneven ion/electron distribution and transfer at the anode/electrolyte interface, thus promoting uniform deposition and stripping of Li+ at high-rate situations. As a result, the symmetrical Li || Li batteries with polarized PVDF coating exhibit a long cycling lifespan over 900 h under 2 mA cm-2 with marginal voltage polarization, and an ultra-high-rate performance up to 8.85 mA cm-2 . The full cells using LiFePO4 cathode also display enhanced electrochemical performance. The innovative strategy of ferroelectric polarization sheds light on interface engineering to circumvent Li dendrite growth in lithium metal batteries (LMBs).

8.
Small ; 20(20): e2308741, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38112264

RESUMEN

Recently, nonmetal NH4 + ions have attracted extensive attention for use as charge carries in the field of energy storage due to their abundant resources, environmental friendliness, and low cost. However, the development of aqueous ammonium-ion batteries (AAIBs) is constrained by the absence of high-voltage and long-life materials. Herein, different tunnel-structure MnO2 materials (α-, ß-, and γ-MnO2) are utilized as cathodes for AAIBs and hybrid-ion batteries and compared, and α-MnO2 is demonstrated to exhibit the most remarkable electrochemical performance. The α-MnO2 cathode material delivers the highest discharge capacity of 219 mAh g-1 at a current density of 0.1 A g-1 and the best cyclability with a capacity retention of 95.4% after 10 000 cycles at 1.0 A g-1. Moreover, aqueous ammonium-ion and hybrid-ion (ammonium/sodium ions) full batteries are successfully constructed using α-MnO2 cathodes. This work provides a novel direction for the development of aqueous energy storage for practical applications.

9.
Chembiochem ; 25(7): e202300812, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38351400

RESUMEN

Biocatalysis has emerged as a powerful alternative to traditional chemical methods, especially for asymmetric synthesis. As biocatalysts usually exhibit excellent chemical, regio- and enantioselectivity, they facilitate and simplify many chemical processes for the production of a broad range of products. Here, a new biocatalyst called, R-selective amine transaminases (R-ATAs), was obtained from Mycobacterium sp. ACS1612 (M16AT) using in-silico prediction combined with a genome and protein database. A two-step simple purification process could yield a high concentration of pure enzyme, suggesting that industrial application would be inexpensive. Additionally, the newly identified and characterized R-ATAs displayed a broad substrate spectrum and strong tolerance to organic solvents. Moreover, the synthetic applicability of M16AT has been demonstrated by the asymmetric synthesis of (R)-fendiline from of (R)-1-phenylethan-1-amine.


Asunto(s)
Aminas , Mycobacterium , Aminas/química , Transaminasas/metabolismo , Especificidad por Sustrato , Biocatálisis
10.
Plant Physiol ; 193(2): 1597-1604, 2023 09 22.
Artículo en Inglés | MEDLINE | ID: mdl-37335930

RESUMEN

Carbon monoxide (CO) is a recently discovered gasotransmitter. In animals, it has been found that endogenously produced CO participates in the regulation of various metabolic processes. Recent research has indicated that CO, acting as a signaling molecule, plays a crucial regulatory role in plant development and their response to abiotic stress. In this work, we developed a fluorescent probe, named COP (carbonic oxide Probe), for the in situ imaging of CO in Arabidopsis thaliana plant tissues. The probe was designed by combining malononitrile-naphthalene as the fluorophore and a typical palladium-mediated reaction mechanism. When reacted with the released CO, COP showed an obvious fluorescence enhancement at 575 nm, which could be observed in naked-eye conditions. With a linear range of 0-10 µM, the limit of detection of COP was determined as 0.38 µM. The detection system based on COP indicated several advantages including relatively rapid response within 20 min, steadiness in a wide pH range of 5.0-10.0, high selectivity, and applicative anti-interference. Moreover, with a penetration depth of 30 µm, COP enabled 3D imaging of CO dynamics in plant samples, whether it was caused by agent release, heavy metal stress, or inner oxidation. This work provides a fluorescent probe for monitoring CO levels in plant samples, and it expands the application field of CO-detection technology, assisting researchers in understanding the dynamic changes in plant physiological processes, making it an important tool for studying plant physiology and biological processes.


Asunto(s)
Colorantes Fluorescentes , Gasotransmisores , Animales , Colorantes Fluorescentes/química , Monóxido de Carbono/metabolismo , Fluorescencia
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