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1.
Bioorg Chem ; 147: 107352, 2024 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-38640719

RESUMO

Glypican-3 (GPC3) is markedly overexpressed in hepatocellular carcinoma (HCC) and not expressed in normal liver tissues. In this study, a novel peptide PET imaging agent ([18F]AlF-NOTA-IPB-GPC3P) was developed to target GPC3 expressed in tumors. The overall radiochemical yield of [18F]AlF-NOTA-IPB-GPC3P was 10-15 %, and its lipophilicity, expressed as the logD value at a pH of 7.4, was -1.18 ± 0.06 (n = 3). Compared to the previously reported tracer [18F]AlF-GP2633, [18F]AlF-NOTA-IPB-GPC3P exhibited higher cellular uptake (15.13 vs 5.96) and internalized rate (80.63 % vs 35.93 %) in Huh7 cells at 120 min. Micro-PET/CT and biodistribution studies further demonstrated that [18F]AlF-NOTA-IPB-GPC3P exhibited significantly increased tumor uptake and prolonged tumor residence in Huh7 tumors compared to [18F]AlF-GP2633 (4.66 ± 0.22 % ID/g vs 0.72 ± 0.09 % ID/g at 60 min, p < 0.001; 5.05 ± 0.23 % ID/g vs 0.35 ± 0.08 % ID/g at 120 min, p < 0.001, respectively). Furthermore, the tumor-to-organ ratios of [18F]AlF-NOTA-IPB-GPC3P surpassed those of [18F]AlF-GP2633. Our results support the utilization of [18F]AlF-NOTA-IPB-GPC3P as a PET imaging agent targeting the GPC3 receptor for tumor detection.

2.
Phytochemistry ; : 114096, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38641141

RESUMO

Forsythiae Fructus (FF), the dried fruit of F. suspensa, is commonly used to treat fever, inflammation, etc in China or other Asian countries. FF is usually used as the core herb in traditional Chinese medicine preparations for the treatment of influenza, such as Shuang-huang-lian oral liquid and Yin-qiao powder, etc. Since the wide application and core role of FF, its research progress was summarized in terms of traditional uses, phytochemistry, pharmacology, pharmacokinetics, quality control, and toxicity. Meanwhile, the anti-influenza substances and mechanism of FF were emphasized. Till now, a total of 290 chemical components are identified in F. suspensa, and among them, 248 components were isolated and identified from FF, including 42 phenylethanoid glycosides, 48 lignans, 59 terpenoids, 14 flavonoids, 3 steroids, 24 cyclohexyl ethanol derivatives, 14 alkaloids, 26 organic acids, and 18 other types. FF and their pure compounds have the pharmacological activities of anti-virus, anti-inflammation, anti-oxidant, anti-bacteria, anti-tumor, neuroprotection, hepatoprotection, etc. Inhibition of TLR7, RIG-I, MAVS, NF-κB, MyD88 signaling pathway were the reported anti-influenza mechanisms of FF and phenylethanoid glycosides and lignans are the main active groups. However, the bioavailability of phenylethanoid glycosides and lignans of FF in vivo was low, which needed to be improved. Simultaneously, the un-elucidated compounds and anti-influenza substances of FF strongly needed to be explored. The current quality control of FF was only about forsythoside A and phillyrin, more active components should be taken into consideration. Moreover, there are no reports of toxicity of FF yet, but the toxicity of FF should be not neglected in clinical applications.

3.
J Ethnopharmacol ; : 118224, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38642623

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Sophorae tonkinensis Radix et Rhizoma (STR) is an extensively applied traditional Chinese medicine (TCM) in southwest China. However, its clinical application is relatively limited due to its hepatotoxicity effects. AIM OF THE STUDY: To understand the material foundation and liver injury mechanism of STR. MATERIALS AND METHODS: Chemical compositions in STR and its prototypes in mice were profiled by ultra-performance liquid chromatography coupled quadrupole-time of flight mass spectrometry (UPLC-Q/TOF MS). STR-induced liver injury (SILI) was comprehensively evaluated by STR-treated mice mode. The histopathologic and biochemical analyses were performed to evaluate liver injury levels. Subsequently, network pharmacology and multi-omics were used to analyze the potential mechanism of SILI in vivo. And the target genes were further verified by western blot. RESULTS: A total of 152 compounds were identified or tentatively characterized in STR, including 29 alkaloids, 21 organic acids, 75 flavonoids, 1 quinone, and 26 other types. Among them, 19 components were presented in STR-medicated serum. The histopathologic and biochemical analysis revealed that hepatic injury occurred after 4 weeks of intragastric administration of STR. Network pharmacology analysis revealed that IL6, TNF, STAT3, etc. were the main core targets, and the bile secretion might play a key role in SILI. The metabolic pathways such as taurine and hypotaurine metabolism, purine metabolism, and vitamin B6 metabolism were identified in the STR exposed groups. Among them, taurine, hypotaurine, hypoxanthine, pyridoxal, and 4-pyridoxate were selected based on their high impact value and potential biological function in the process of liver injury post STR treatment. CONCLUSIONS: The mechanism and material foundation of SILI were revealed and profiled by a multi-omics strategy combined with network pharmacology and chemical profiling. Meanwhile, new insights were taken into understand the pathological mechanism of SILI.

4.
Phys Med Biol ; 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38636505

RESUMO

OBJECTIVE: Pharmacokinetic parametric images obtained through dynamic fluorescence molecular tomography (DFMT) has ability of capturing dynamic changes in fluorescence concentration, thereby providing three-dimensional metabolic information for applications in biological research and drug development. However, data processing of DFMT is time-consuming, involves a vast amount of data, and the problem itself is ill-posed, which significantly limits the application of pharmacokinetic parametric images reconstruction. In this study, group sparse-based Taylor expansion (GSTE) method is proposed to address these problems. APPROACH: Firstly, Taylor expansion framework is introduced to reduce time and computational cost. Secondly, group sparsity based on structural prior is introduced to improve reconstruction accuracy. Thirdly, alternating iterative solution based on accelerated gradient descent (AGD) algorithm is introduced to solve the problem. MAIN RESULTS: Numerical simulation and in vivo experimental results demonstrate that, in comparison to existing methods, the proposed approach significantly enhances reconstruction speed without a degradation of quality, particularly when confronted with background fluorescence interference from other organs. SIGNIFICANCE: Our research greatly reduces time and computational cost, providing strong support for real-time monitoring of liver metabolism.

5.
J Phys Chem Lett ; 15(13): 3486-3492, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38513132

RESUMO

Atomic-level modulation of the metal-oxide interface is considered an effective approach to optimize the electronic structure and catalytic activity of metal catalysts but remains highly challenging. Here, we employ the atomic layer deposition (ALD) technique together with a heteroatom doping strategy to effectively tailor the electronic metal-support interaction (EMSI) at the metal-oxide interface on the atomic level, thereby achieving high hydrogen evolution performance and Pt utilization. Theoretical calculations reveal that the doping of N atoms in Co3O4 significantly adjusts the EMSI between Pt-Co3O4 interfaces and, consequently, alters the d-band center of Pt and optimizes the adsorption/desorption of reaction intermediates. This work sheds light on the atomic-level regulation and mechanistic understanding of the EMSI in metal-oxide, while providing guidance for the development of advanced EMSI electrocatalysts for various future energy applications.

6.
Bioorg Chem ; 145: 107193, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38442611

RESUMO

Immunotherapy has brought great benefits to cancer patients, but only some patients benefit from it. Noninvasive, real-time and dynamic monitoring of the effectiveness of immunotherapy through PET imaging may provide assistance for the treatment plan of immunotherapy. In this study, we designed and synthesized a new targeted PD-L1 peptide NOTA-PEG2-Asp2-PDL1P, which was labeled with nuclide 18F to obtain a new imaging agent [18F]AlF-NOTA-PEG2-Asp2-PDL1P. The total radiochemical yield of [18F]AlF-NOTA-PEG2-Asp2-PDL1P was 13.7 % (Uncorrected radiochemical yield, n > 5). [18F]AlF-NOTA-PEG2-Asp2-PDL1P achieved high radiochemical purity (>95 %) with a molar activity more than 51.2 GBq/µmol. [18F]AlF-NOTA-PEG2-Asp2-PDL1P exhibited good hydrophilicity and had good stability both in vivo and in vitro, it can specifically targets B16F10 tumor with PD-L1 expression, and had a relatively high retention in tumor, a relatively fast clearance in vivo and a higher tumor-to-non-target ratio, all of which could make [18F]AlF-NOTA-PEG2-Asp2-PDL1P a potential tracer for PD-L1 prediction before clinical immunotherapy.


Assuntos
Compostos Heterocíclicos com 1 Anel , Compostos Heterocíclicos , Neoplasias , Humanos , Compostos Heterocíclicos/química , Sondas Moleculares , Antígeno B7-H1/metabolismo , Radioisótopos de Flúor/química , Tomografia por Emissão de Pósitrons/métodos , Compostos Radiofarmacêuticos/química , Linhagem Celular Tumoral
7.
Sci Adv ; 10(12): eadn4372, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38507487

RESUMO

Grating couplers that interconnect photonic chips to off-chip components are crucial for various optoelectronics applications. Despite numerous efforts in past decades, the existing grating couplers are still far from optimal in energy efficiency and thus hinder photonic integration toward a larger scale. Here, we propose a strategy to achieve ultralow-loss grating couplers by using unidirectional guided resonances (UGRs), suppressing the useless downward radiation with no mirror on the bottom. By engineering the dispersion and apodizing the geometry of grating, we experimentally realize a grating coupler with a record-low loss of -0.34 dB and 1-dB bandwidth exceeding 30 nm at the telecom wavelength of 1550 nm and further demonstrate an optic via with a loss of only -0.94 dB. Given that UGRs ubiquitously exist in a variety of grating geometries, our work sheds light on a systematic method to achieve energy-efficient optical interconnect and paves the way to large-scale photonic integration.

8.
Fish Shellfish Immunol ; 148: 109504, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38508539

RESUMO

Aeromonas hydrophila is a commonly pathogenic bacterium in cultivated eels, but its pathogenicity to American eel (Anguilla rostrata) and the molecular mechanism of host anti-A. hydrophila infection remains uncertain. In this study, LD50 of A. hydrophila to American eels was determined and bacterial load in the liver and kidney of eels was assessed post 2.56 doses of LD50 of A. hydrophila infection. The results showed that the LD50 of A. hydrophila to American eels was determined to be 3.9 × 105 cfu/g body weight (7.8 × 106 cfu/fish), and the bacterial load peaked at 36 h post the infection (hpi) in the liver. Then, the histopathology was highlighted by congestion in splenic blood vessels, atrophied glomeruli, and necrotic hepatocytes. Additionally, the results of qRT-PCR revealed that 18 host immune-related genes showed significantly up or downregulated post-infection compare to that of pre-infection. Finally, results of the RNA-seq revealed 10 hub DEGs and 7 encoded proteins play essential role to the anti-A. hydrophila infection in American eels. Pathogenicity of A. hydrophila to American eels and RNA-seq of host anti-A. hydrophila infection were firstly reported in this study, shedding new light on our understanding of the A. hydrophila pathogenesis and the host immune response to the A. hydrophila infection strategies in gene transcript.


Assuntos
Anguilla , Doenças dos Peixes , Animais , Aeromonas hydrophila , Virulência , Proteínas da Membrana Bacteriana Externa , Perfilação da Expressão Gênica/veterinária
9.
Phytochemistry ; 221: 114064, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38508326

RESUMO

Abri Herba (AH, known as 'Ji-Gu-Cao' in China) has a long-term medicinal history of treating cholecystitis, acute and chronic hepatitis and non-alcoholic fatty liver (NAFL) in China or other Asian countries. This review aimed to provide a comprehensive analysis of AH in terms of ethnopharmacology, phytochemistry, pharmacology, pharmacokinetics and toxicology. The information involved in the study was collected from a variety of electronic resources, and >100 scientific studies have been used since 1962. Until now, 95 chemical compounds have been isolated and identified from AH and the seeds of Abrus cantoniensis Hance (ACH), including 47 terpenoids, 26 flavonoids and 4 alkaloids. The pharmacological activities of AH extracts and their pure compounds have been explored in the aspects of anti-hyperlipidaemia, hepatoprotection, anti-tumour, anti-viral, anti-bacterial, anti-inflammatory and analgesic, immunomodulation, antioxidant and others. The pharmacokinetics and excretion kinetics of AH in vivo and 15 traditional and clinical prescriptions containing AH have been sorted out, and the potential therapeutic mechanism and drug metabolism pattern were also summarised. The pods of ACH are toxic, with a median lethal dose (LD50) of 10.01 ± 2.90 g/kg (i.g.) in mice. Interestingly, the toxicity of ACH's pods and seeds decreased after boiling. However, the toxicity mechanism of pods of ACH is unclear, limiting its clinical application. Clinical trials in the future should be used to explore its safety. Meanwhile, as one of the relevant pharmacological activities, the effects and mechanism of AH on anti-hyperlipidaemia and hepatoprotection should be further studied, which is of great significance for understanding its mechanism of action in the treatment of NAFL disease and improving its clinical application.


Assuntos
Alcaloides , Extratos Vegetais , Animais , Camundongos , Etnofarmacologia , Extratos Vegetais/química , Medicina Tradicional Chinesa , Anti-Inflamatórios , Compostos Fitoquímicos
10.
Nat Commun ; 15(1): 1036, 2024 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-38310109

RESUMO

Social recognition encompasses encoding social information and distinguishing unfamiliar from familiar individuals to form social relationships. Although the medial prefrontal cortex (mPFC) is known to play a role in social behavior, how identity information is processed and by which route it is communicated in the brain remains unclear. Here we report that a ventral midline thalamic area, nucleus reuniens (Re) that has reciprocal connections with the mPFC, is critical for social recognition in male mice. In vivo single-unit recordings and decoding analysis reveal that neural populations in both mPFC and Re represent different social stimuli, however, mPFC coding capacity is stronger. We demonstrate that chemogenetic inhibitions of Re impair the mPFC-Re neural synchronization and the mPFC social coding. Projection pathway-specific inhibitions by optogenetics reveal that the reciprocal connectivity between the mPFC and the Re is necessary for social recognition. These results reveal an mPFC-thalamic circuit for social information processing.


Assuntos
Núcleos da Linha Média do Tálamo , Tálamo , Masculino , Camundongos , Animais , Reconhecimento Psicológico , Córtex Pré-Frontal , Vias Neurais
11.
Environ Sci Technol ; 58(8): 3787-3799, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38350416

RESUMO

Plug-in electric vehicles (PEVs) can reduce air emissions when charged with clean power, but prior work estimated that in 2010, PEVs produced 2 to 3 times the consequential air emission externalities of gasoline vehicles in PJM (the largest US regional transmission operator, serving 65 million people) due largely to increased generation from coal-fired power plants to charge the vehicles. We investigate how this situation has changed since 2010, where we are now, and what the largest levers are for reducing PEV consequential life cycle emission externalities in the near future. We estimate that PEV emission externalities have dropped by 17% to 18% in PJM as natural gas replaced coal, but they will remain comparable to gasoline vehicle externalities in base case trajectories through at least 2035. Increased wind and solar power capacity is critical to achieving deep decarbonization in the long run, but through 2035 we estimate that it will primarily shift which fossil generators operate on the margin at times when PEVs charge and can even increase consequential PEV charging emissions in the near term. We find that the largest levers for reducing PEV emissions over the next decade are (1) shifting away from nickel-based batteries to lithium iron phosphate, (2) reducing emissions from fossil generators, and (3) revising vehicle fleet emission standards. While our numerical estimates are regionally specific, key findings apply to most power systems today, in which renewable generators typically produce as much output as possible, regardless of the load, while dispatchable fossil fuel generators respond to the changes in load.


Assuntos
Poluição do Ar , Gasolina , Humanos , Gasolina/análise , Emissões de Veículos/prevenção & controle , Emissões de Veículos/análise , Centrais Elétricas , Políticas , Carvão Mineral , Gás Natural , Veículos Automotores
12.
Inorg Chem ; 63(9): 4373-4384, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38376825

RESUMO

Efficient and durable bifunctional catalysts toward oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) are urgently desirable but challenging for rechargeable Zn-air batteries (ZABs), especially flexible wearable ZABs. Inspired by the vine-leaf-whisker structure in nature, we proposed a three-dimensional (3D) hierarchical bifunctional catalyst (denoted as Co-Fe-Zn@N-CNT/CNF) consisting of N-doped carbon nanotubes embedded with abundant CoFe alloy nanoparticles, leaf-shaped N-doped carbon nanoflakes, and porous carbon fibers for rechargeable ZABs. The special biomimetic structure provides a large specific surface area, allowing for high exposure of the active site and ensuring fast mass transport/charge transfer. The close combination of CoFe bimetallic alloys and N-doped carbon nanotubes delivers high electrocatalytic activity, while the coexistence of various active sites such as metal nanoparticles (NPs), metal-Nx, doped N species, and their synergistic interactions endows the catalysts with more active sites. As such, the Co-Fe-Zn@N-CNT/CNF catalyst achieves superior bifunctional catalytic activities for the ORR (a half-wave potential of 0.84 V) and the OER (an overpotential of 326 mV at 10 mA cm-2) in alkaline media, comparable to commercial Pt/C and RuO2. Remarkably, both aqueous and solid-state ZABs assembled with Co-Fe-Zn@N-CNT/CNF catalysts as air electrodes demonstrate excellent charging/discharging performance, high peak power density, and robust long-term cycling stability. More interestingly, the flexible ZAB performs well even under bending conditions, displaying satisfactory device stability and mechanical flexibility. This study presents a new collective morphological-composition-structural engineering strategy for exploiting the efficient bifunctional oxygen electrocatalysts, which is of great significance for high-performance rechargeable ZABs and wearable energy storage devices.

13.
Mar Biotechnol (NY) ; 2024 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-38367180

RESUMO

Vibrio harveyi, a recently discovered pathogenic bacterium isolated from American eels (Anguilla rostrata), poses uncertainties regarding its pathogenesis in American eel and the molecular mechanisms underlying host defense against V. harveyi infection. This study aimed to determine the LD50 of V. harveyi in American eel and assess the bacterial load in the liver, spleen, and kidney post-infection with the LD50 dose. The results showed that the LD50 of V. harveyi via intraperitoneal injection in American eels over a 14d period was determined to be 1.24 × 103 cfu/g body weight (6.2 × 104 cfu/fish). The peak bacterial load occurred at 36 h post-infection (hpi) in all three organs examined. Histopathology analysis revealed hepatic vein congestion and thrombi, tubular vacuolar degeneration, and splenic bleeding. Moreover, quantitative reverse transcription polymerase chain reaction (qRT-PCR) results indicated significant up or downregulation of 18 host immune- or anti-infection-related genes post 12 to 60 hpi following the infection. Additionally, RNA sequencing (RNA-seq) unveiled 7 hub differentially expressed genes (DEGs) and 11 encoded proteins play crucial roles in the anti-V. harveyi response in American eels. This study firstly represents the comprehensive report on the pathogenicity of V. harveyi to American eels and RNA-seq of host's response to V. harveyi infection. These findings provide valuable insights into V. harveyi pathogenesis and the strategies employed by the host's immune system at the transcriptomic level to combat V. harveyi infection.

14.
Cell Metab ; 36(4): 839-856.e8, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38367623

RESUMO

Utilization of lipids as energy substrates after birth causes cardiomyocyte (CM) cell-cycle arrest and loss of regenerative capacity in mammalian hearts. Beyond energy provision, proper management of lipid composition is crucial for cellular and organismal health, but its role in heart regeneration remains unclear. Here, we demonstrate widespread sphingolipid metabolism remodeling in neonatal hearts after injury and find that SphK1 and SphK2, isoenzymes producing the same sphingolipid metabolite sphingosine-1-phosphate (S1P), differently regulate cardiac regeneration. SphK2 is downregulated during heart development and determines CM proliferation via nuclear S1P-dependent modulation of histone acetylation. Reactivation of SphK2 induces adult CM cell-cycle re-entry and cytokinesis, thereby enhancing regeneration. Conversely, SphK1 is upregulated during development and promotes fibrosis through an S1P autocrine mechanism in cardiac fibroblasts. By fine-tuning the activity of each SphK isoform, we develop a therapy that simultaneously promotes myocardial repair and restricts fibrotic scarring to regenerate the infarcted adult hearts.


Assuntos
Coração , Lisofosfolipídeos , Esfingolipídeos , Esfingosina/análogos & derivados , Animais , Esfingolipídeos/metabolismo , Isoenzimas , Mamíferos/metabolismo , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo
15.
J Ethnopharmacol ; 323: 117697, 2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38185261

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Lonicerae Japonicae Flos (LJF) and Lonicerae Flos (LF) were once used as the same herb in China, but they were distinguished by Chinese Pharmacopoeia in 2005 in terms of their medicinal history, plant morphology, medicinal properties and chemical constituents. However, their functions, flavor, and meridian tropism are the same according to the Chinese pharmacopoeia 2020 edition, making researchers and customers confused. AIM OF THE REVIEW: This review aimed to provide a comparative analysis of LJF and LF in order to provide a rational application in future research. MATERIALS AND METHODS: The information was gathered from China National Knowledge Infrastructure (CNKI), SciFinder, Google Scholar, PubMed, Web of Science, and Chinese Masters and Doctoral Dissertations (all chosen articles were reviewed attentively from 1980.1 to 2023.8). RESULTS: Till now, 507 chemical compounds have been isolated and identified in LJF, while 223 ones (79 overlapped compounds) are found in LF, including organic acids and derivatives, flavonoids, triterpenoids, iridoids, and essential oil components, etc. In addition, the pharmacological activities of LJF and LF, especially for their anti-influenza efficacy and mechanism, and their difference in terms of pharmacokinetic parameters, toxicology, and clinical applications were also summarized. CONCLUSION: The current work offers comparative information between LJF and LF in terms of botany, traditional uses, phytochemistry, ethnopharmacology, pharmacokinetics, toxicology, and pharmacology, especially their anti-influenza activities. Despite the same clinical applications and similar chemical components in LJF and LF, differentiated components were still existed, resulting in differentiated pharmacological activities and pharmacokinetics parameters. Moreover, the research about anti-influenza mechanism and functional substances of LJF and LF is dramatically limited, restricting their clinical applications. In addition, few studies have investigated the metabolism feature of LF in vivo, which is one of the important bases for revealing the pharmacological mechanism of LF. At the same time, the toxicity of LJF and LF is not fully studied, and the toxic compounds of LJF and LF need to be screened out in order to standardize the drug use and improve their rational applications.


Assuntos
Medicamentos de Ervas Chinesas , Lonicera , Óleos Voláteis , Extratos Vegetais/farmacologia , Lonicera/química , Etnofarmacologia , Óleos Voláteis/farmacologia , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/uso terapêutico , Medicamentos de Ervas Chinesas/química , Cromatografia Líquida de Alta Pressão
16.
Plant Cell ; 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38271284

RESUMO

Photoperiod is a crucial environmental cue for phenological responses, including growth cessation and winter dormancy in perennial woody plants. Two regulatory modules within the photoperiod pathway explain bud dormancy induction in poplar (Populus spp.): the circadian oscillator LATE ELONGATED HYPOCOTYL 2 (LHY2) and GIGANTEA-like genes (GIs) both regulate the key target for winter dormancy induction FLOWERING LOCUS T2 (FT2). However, modification of LHY2 and GIs cannot completely prevent growth cessation and bud set under short-day conditions, indicating that additional regulatory modules are likely involved. We identified PtoHY5a, an orthologs of the photomorphogenesis regulatory factor ELONGATED HYPOCOTYL 5 (HY5) in poplar (Populus tomentosa), that directly activates PtoFT2 expression and represses the circadian oscillation of LHY2, indirectly activating PtoFT2 expression. Thus, PtoHY5a suppresses short day-induced growth cessation and bud set. Accordingly, PtoHY5a knockout facilitates dormancy induction. PtoHY5a also inhibits bud-break in poplar by controlling gibberellic acid (GA) levels in apical buds. Additionally, PtoHY5a regulates the photoperiodic control of seasonal growth downstream of phytochrome PHYB2. Thus, PtoHY5a modulates seasonal growth in poplar by regulating the PtoPHYB2-PtoHY5a-PtoFT2 module to determine the onset of winter dormancy, and by fine-tuning GA levels to control bud-break.

17.
J Plant Physiol ; 292: 154149, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38064888

RESUMO

Drought poses a serious challenge to sustained plant growth and crop yields in the context of global climate change. Drought tolerance in poplars and their underlying mechanisms still remain largely unknown. In this article, we investigated the overexpression of PtoMYB99 - both a drought and abscisic acid (ABA) induced gene constraining drought tolerance in poplars (as compared with wild type poplars). First, we found that PtoMYB99-OE lines exhibited increased stomatal opening and conductance, higher transpiration and photosynthetic rates, as well as reduced levels of ABA and jasmonic acid (JA). Second, PtoMYB99-OE lines accumulated more reactive oxygen species (ROS), including H2O2 and O2-, as well as malonaldehyde (MDA), proline, and soluble sugar under osmotic stress; conversely, the activity of antioxidant enzymes (SOD, POD, and CAT), was weakened in the PtoMYB99-OE lines. Third, the expression of ABA biosynthetic genes, PtoNCED3.1 and PtoNCED3.2, as well as JA biosynthetic genes, PtoOPR3.1 and PtoOPR3.2, was significantly reduced in the PtoMYB99-OE lines under both normal conditions and osmotic stress. Based on our results, we conclude that the overexpression of PtoMYB99 compromises tolerance to osmotic stress in poplar. These findings contribute to the understanding of the role of the MYB genes in drought stress and the biosynthesis of ABA and JA.


Assuntos
Ácido Abscísico , Peróxido de Hidrogênio , Ácido Abscísico/metabolismo , Pressão Osmótica , Peróxido de Hidrogênio/metabolismo , Antioxidantes/metabolismo , Transporte Biológico , Secas , Estresse Fisiológico/genética , Regulação da Expressão Gênica de Plantas , Plantas Geneticamente Modificadas/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
18.
Med Image Anal ; 91: 103029, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37988921

RESUMO

Imaging markers of cerebral small vessel disease provide valuable information on brain health, but their manual assessment is time-consuming and hampered by substantial intra- and interrater variability. Automated rating may benefit biomedical research, as well as clinical assessment, but diagnostic reliability of existing algorithms is unknown. Here, we present the results of the VAscular Lesions DetectiOn and Segmentation (Where is VALDO?) challenge that was run as a satellite event at the international conference on Medical Image Computing and Computer Aided Intervention (MICCAI) 2021. This challenge aimed to promote the development of methods for automated detection and segmentation of small and sparse imaging markers of cerebral small vessel disease, namely enlarged perivascular spaces (EPVS) (Task 1), cerebral microbleeds (Task 2) and lacunes of presumed vascular origin (Task 3) while leveraging weak and noisy labels. Overall, 12 teams participated in the challenge proposing solutions for one or more tasks (4 for Task 1-EPVS, 9 for Task 2-Microbleeds and 6 for Task 3-Lacunes). Multi-cohort data was used in both training and evaluation. Results showed a large variability in performance both across teams and across tasks, with promising results notably for Task 1-EPVS and Task 2-Microbleeds and not practically useful results yet for Task 3-Lacunes. It also highlighted the performance inconsistency across cases that may deter use at an individual level, while still proving useful at a population level.


Assuntos
Doenças de Pequenos Vasos Cerebrais , Imageamento por Ressonância Magnética , Humanos , Imageamento por Ressonância Magnética/métodos , Reprodutibilidade dos Testes , Doenças de Pequenos Vasos Cerebrais/diagnóstico por imagem , Hemorragia Cerebral , Computadores
19.
Cell Death Dis ; 14(12): 793, 2023 12 04.
Artigo em Inglês | MEDLINE | ID: mdl-38049405

RESUMO

Pyroptosis, a mode of inflammatory cell death, has recently gained significant attention. However, the underlying mechanism remains poorly understood. HGS-ETR1/2 is a humanized monoclonal antibody that can bind to DR4/5 on the cell membrane and induce cell apoptosis by activating the death receptor signalling pathway. In this study, by using morphological observation, fluorescence double staining, LDH release and immunoblot detection, we confirmed for the first time that HGS-ETR1/2 can induce GSDME-mediated pyroptosis in hepatocellular carcinoma cells. Our study found that both inhibition of the AKT signalling pathway and silencing of CPA4 promote pyroptosis, while the overexpression of CPA4 inhibits it. Furthermore, we identified a positive regulatory feedback loop is formed between CPA4 and AKT phosphorylation. Specifically, CPA4 modulates AKT phosphorylation by regulating the expression of the AKT phosphatase PP2A, while inhibition of the AKT signalling pathway leads to a decreased transcription and translation levels of CPA4. Our study reveals a novel mechanism of pyroptosis induced by HGS-ETR1/2, which may provide a crucial foundation for future investigations into cancer immunotherapy.


Assuntos
Proteínas Proto-Oncogênicas c-akt , Piroptose , Transdução de Sinais , Carboxipeptidases , Linhagem Celular Tumoral , Piroptose/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos
20.
J Clin Microbiol ; 61(12): e0071023, 2023 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-38038482

RESUMO

The emergence of Rocahepevirus ratti [species HEV ratti (r HEV)] as a causative agent of hepatitis E in humans presents a new potential threat to global public health. The R. ratti genotype 1 (r-1 HEV) variant only shares 50%-60% genomic identity with Paslahepevirus balayani [species HEV balayani (b HEV)] variants, which are the main causes of hepatitis E infection in humans. Here, we report antigen diagnoses for r-1 HEV and b HEV using an enzymatic immunoassay (EIA) method. We detected recombinant virus-like particles protein (HEV 239) of r HEV and b HEV using a collection of hepatitis E virus (HEV)-specific monoclonal antibodies. Two optimal candidates, the capture antibody P#1-H4 and the detection antibodies C145 (P#1-H4*/C145#) and C158 (P#1-H4*/C158#), were selected to detect antigen in infected rat samples and r-1 HEV- or b HEV-infected human clinical samples. The two candidates showed similar diagnostic efficacy to the Wantai HEV antigen kit in b HEV-infected clinical samples. Genomic divergence resulted in low diagnostic efficacy of the Wantai HEV antigen kit (0%, 0 of 10) for detecting r-1 HEV infection. Compared with the P#1-H4*/C145# candidate (80%, 8 of 10), the P#1-H4*/C158# candidate had excellent diagnostic efficacy in r-1 HEV-infected clinical samples (100%, 10 of 10). The two candidates bind to a discrete antigenic site that is highly conserved across r HEV and b HEV. P#1-H4*/C145# and P#1-H4*/C158# are efficacious candidate antibody combinations for rat HEV antigen detection.


Assuntos
Vírus da Hepatite E , Hepatite E , Ratos , Humanos , Animais , Vírus da Hepatite E/genética , Anticorpos Anti-Hepatite , Técnicas Imunoenzimáticas , Testes Imunológicos
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