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1.
Immunol Rev ; 321(1): 211-227, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37715546

RESUMO

Copper is an essential nutrient for maintaining enzyme activity and transcription factor function. Excess copper results in the aggregation of lipoylated dihydrolipoamide S-acetyltransferase (DLAT), which correlates to the mitochondrial tricarboxylic acid (TCA) cycle, resulting in proteotoxic stress and eliciting a novel cell death modality: cuproptosis. Cuproptosis exerts an indispensable role in cancer progression, which is considered a promising strategy for cancer therapy. Cancer immunotherapy has gained extensive attention owing to breakthroughs in immune checkpoint blockade; furthermore, cuproptosis is strongly connected to the modulation of antitumor immunity. Thus, a thorough recognition concerning the mechanisms involved in the modulation of copper metabolism and cuproptosis may facilitate improvement in cancer management. This review outlines the cellular and molecular mechanisms and characteristics of cuproptosis and the links of the novel regulated cell death modality with human cancers. We also review the current knowledge on the complex effects of cuproptosis on antitumor immunity and immune response. Furthermore, potential agents that elicit cuproptosis pathways are summarized. Lastly, we discuss the influence of cuproptosis induction on the tumor microenvironment as well as the challenges of adding cuproptosis regulators to therapeutic strategies beyond traditional therapy.


Assuntos
Cobre , Neoplasias , Humanos , Neoplasias/terapia , Imunoterapia , Morte Celular , Homeostase , Apoptose , Microambiente Tumoral
2.
Proc Natl Acad Sci U S A ; 120(17): e2221459120, 2023 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-37068247

RESUMO

Growing population and consumption pose unprecedented demands on food production. However, ammonia emissions mainly from food systems increase oceanic nitrogen deposition contributing to eutrophication. Here, we developed a long-term oceanic nitrogen deposition dataset (1970 to 2018) with updated ammonia emissions from food systems, evaluated the impact of ammonia emissions on oceanic nitrogen deposition patterns, and discussed the potential impact of nitrogen fertilizer overuse. Based on the chemical transport modeling approach, oceanic ammonia-related nitrogen deposition increased by 89% globally between 1970 and 2018, and now, it exceeds oxidized nitrogen deposition by over 20% in coastal regions including China Sea, India Coastal, and Northeastern Atlantic Shelves. Approximately 38% of agricultural nitrogen fertilizer was excessive, which corresponds to 15% of global oceanic ammonia-related nitrogen deposition. Policymakers and water quality managers need to pay increasingly more attention to ammonia associated with food production if the goal of reducing coastal nitrogen pollution is to be achieved for Sustainable Development Goals.


Assuntos
Amônia , Nitrogênio , Nitrogênio/análise , Amônia/análise , Fertilizantes/análise , Agricultura , China , Qualidade da Água , Solo
3.
Genome Res ; 32(10): 1918-1929, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36220609

RESUMO

Extensive evidence indicates that the pathobiological processes of a complex disease are associated with perturbation in specific neighborhoods of the human protein-protein interaction (PPI) network (also known as the interactome), often referred to as the disease module. Many computational methods have been developed to integrate the interactome and omics profiles to extract context-dependent disease modules. Yet, existing methods all have fundamental limitations in terms of rigor and/or efficiency. Here, we developed a statistical physics approach based on the random-field Ising model (RFIM) for disease module detection, which is both mathematically rigorous and computationally efficient. We applied our RFIM approach to genome-wide association studies (GWAS) of ten complex diseases to examine its performance for disease module detection. We found that our RFIM approach outperforms existing methods in terms of computational efficiency, connectivity of disease modules, and robustness to the interactome incompleteness.


Assuntos
Estudo de Associação Genômica Ampla , Mapas de Interação de Proteínas , Humanos , Estudo de Associação Genômica Ampla/métodos , Física , Algoritmos
4.
J Virol ; 98(5): e0017724, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38563731

RESUMO

Cactin, a highly conserved protein, plays a crucial role in various physiological processes in eukaryotes, including innate immunity. Recently, the function of Cactin in the innate immunity of Drosophila has been explored, revealing that Cactin regulates a non-canonical signaling pathway associated with the Toll and Imd pathways via the Cactin-Deaf1 axis. In addition, Cactin exhibits specific antiviral activity against the Drosophila C virus (DCV) in Drosophila, with an unknown mechanism. During DCV infection, it has been confirmed that the protein level and antiviral activity of Cactin are regulated by ubiquitination. However, the precise ubiquitination and deubiquitination mechanisms of Cactin in Drosophila remain unexplored. In this study, we identified ubiquitin-specific protease 14 (Usp14) as a major deubiquitinase for Cactin through comprehensive deubiquitinase screening. Our results demonstrate that Usp14 interacts with the C_Cactus domain of Cactin via its USP domain. Usp14 efficiently removes K48- and K63-linked polyubiquitin chains from Cactin, thereby preventing its degradation through the ubiquitin-proteasome pathway. Usp14 significantly inhibits DCV replication in Drosophila cells by stabilizing Cactin. Moreover, Usp14-deficient fruit flies exhibit increased susceptibility to DCV infection compared to wild-type flies. Collectively, our findings reveal the regulation of ubiquitination and antiviral activity of Cactin by the deubiquitinase Usp14, providing valuable insights into the modulation of Cactin-mediated antiviral activity in Drosophila.IMPORTANCEViral infections pose a severe threat to human health, marked by high pathogenicity and mortality rates. Innate antiviral pathways, such as Toll, Imd, and JAK-STAT, are generally conserved across insects and mammals. Recently, the multi-functionality of Cactin in innate immunity has been identified in Drosophila. In addition to regulating a non-canonical signaling pathway through the Cactin-Deaf1 axis, Cactin exhibits specialized antiviral activity against the Drosophila C virus (DCV) with an unknown mechanism. A previous study emphasized the significance of the Cactin level, regulated by the ubiquitin-proteasome pathway, in modulating antiviral signaling. However, the regulatory mechanisms governing Cactin remain unexplored. In this study, we demonstrate that Usp14 stabilizes Cactin by preventing its ubiquitination and subsequent degradation. Furthermore, Usp14 plays a crucial role in regulating the antiviral function mediated by Cactin. Therefore, our findings elucidate the regulatory mechanism of Cactin in Drosophila, offering a potential target for the prevention and treatment of viral infections.


Assuntos
Proteínas de Drosophila , Imunidade Inata , Ubiquitinação , Animais , Dicistroviridae/metabolismo , Drosophila/metabolismo , Drosophila melanogaster/virologia , Drosophila melanogaster/metabolismo , Proteínas de Drosophila/metabolismo , Proteínas de Drosophila/genética , Transdução de Sinais , Ubiquitina Tiolesterase/metabolismo , Ubiquitina Tiolesterase/genética , Replicação Viral
5.
Plant Cell ; 34(8): 3110-3127, 2022 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-35567529

RESUMO

Signaling by the evolutionarily conserved mitogen-activated protein kinase or extracellular signal-regulated kinase (MAPK/ERK) plays critical roles in converting extracellular stimuli into immune responses. However, whether MAPK/ERK signaling induces virus immunity by directly phosphorylating viral effectors remains largely unknown. Barley yellow striate mosaic virus (BYSMV) is an economically important plant cytorhabdovirus that is transmitted by the small brown planthopper (SBPH, Laodelphax striatellus) in a propagative manner. Here, we found that the barley (Hordeum vulgare) MAPK MPK3 (HvMPK3) and the planthopper ERK (LsERK) proteins interact with the BYSMV nucleoprotein (N) and directly phosphorylate N protein primarily on serine 290. The overexpression of HvMPK3 inhibited BYSMV infection, whereas barley plants treated with the MAPK pathway inhibitor U0126 displayed greater susceptibility to BYSMV. Moreover, knockdown of LsERK promoted virus infection in SBPHs. A phosphomimetic mutant of the N Ser290 (S290D) completely abolished virus infection because of impaired self-interaction of BYSMV N and formation of unstable N-RNA complexes. Altogether, our results demonstrate that the conserved MAPK and ERK directly phosphorylate the viral nucleoprotein to trigger immunity against cross-kingdom infection of BYSMV in host plants and its insect vectors.


Assuntos
Hemípteros , Hordeum , Rhabdoviridae , Animais , Antivirais , Hordeum/genética , Insetos Vetores , Nucleoproteínas/genética , Rhabdoviridae/fisiologia
6.
Exp Cell Res ; 435(1): 113893, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38123008

RESUMO

Triple-negative breast cancer is more common among younger than older women and is associated with the poorest survival outcomes of all breast cancer types. Fluvastatin inhibits tumour progression and induces the autophagy of breast cancer cells; however, the role of autophagy in fluvastatin-induced inhibition of breast cancer metastasis is unknown. Therefore, this study aimed to determine this mechanism. The effect of fluvastatin on human hormone receptor-negative breast cancer cells was evaluated in vitro via migration and wound healing assays, western blotting, and morphological measurements, as well as in vivo using a mouse xenograft model. Chloroquine, a prophylactic medication used to prevent malaria in humans was used as an autophagy inhibitor. We found that fluvastatin administration effectively prevented the migration/invasion of triple-negative breast cancer cells, an effect that was largely dependent on the induction of autophagy. Administration of the autophagy inhibitor chloroquine prevented the fluvastatin-induced suppression of lung metastasis in the nude mouse model. Furthermore, fluvastatin increased Ras homolog family member B (RhoB) expression, and the autophagy and anti-metastatic activity induced by fluvastatin were predominantly dependent on the regulation of RhoB through the protein kinase B-mammalian target of rapamycin (Akt-mTOR) signaling pathway. These results suggest that fluvastatin inhibits the metastasis of triple-negative breast cancer cells by modulating autophagy via the up regulation of RhoB through the AKT-mTOR signaling pathway. Fluvastatin may be a promising therapeutic option for patients with triple-negative breast cancer.


Assuntos
Neoplasias Pulmonares , Neoplasias de Mama Triplo Negativas , Animais , Feminino , Humanos , Camundongos , Autofagia , Linhagem Celular Tumoral , Proliferação de Células , Cloroquina/farmacologia , Cloroquina/uso terapêutico , Fluvastatina/farmacologia , Fluvastatina/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/prevenção & controle , Mamíferos/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/patologia
7.
Proc Natl Acad Sci U S A ; 119(14): e2121998119, 2022 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-35344440

RESUMO

SignificanceAgricultural systems are already major forces of ammonia pollution and environmental degradation. How agricultural ammonia emissions affect the spatio-temporal patterns of nitrogen deposition and where to target future mitigation efforts, remains poorly understood. We develop a substantially complete and coherent agricultural ammonia emissions dataset in nearly recent four decades, and evaluate the relative role of reduced nitrogen in total nitrogen deposition in a spatially explicit way. Global reduced nitrogen deposition has grown rapidly, and will occupy a greater dominant position in total nitrogen deposition without future ammonia regulations. Recognition of agricultural ammonia emissions on nitrogen deposition is critical to formulate effective policies to address ammonia related environmental challenges and protect ecosystems from excessive nitrogen inputs.


Assuntos
Poluentes Atmosféricos , Amônia , Agricultura , Poluentes Atmosféricos/análise , Amônia/análise , Ecossistema , Monitoramento Ambiental , Poluição Ambiental , Nitrogênio/análise
8.
Proc Natl Acad Sci U S A ; 119(32): e2201729119, 2022 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-35917351

RESUMO

The gas-phase formation of new particles less than 1 nm in size and their subsequent growth significantly alters the availability of cloud condensation nuclei (CCN, >30-50 nm), leading to impacts on cloud reflectance and the global radiative budget. However, this growth cannot be accounted for by condensation of typical species driving the initial nucleation. Here, we present evidence that nucleated iodine oxide clusters provide unique sites for the accelerated growth of organic vapors to overcome the coagulation sink. Heterogeneous reactions form low-volatility organic acids and alkylaminium salts in the particle phase, while further oligomerization of small α-dicarbonyls (e.g., glyoxal) drives the particle growth. This identified heterogeneous mechanism explains the occurrence of particle production events at organic vapor concentrations almost an order of magnitude lower than those required for growth via condensation alone. A notable fraction of iodine associated with these growing particles is recycled back into the gas phase, suggesting an effective transport mechanism for iodine to remote regions, acting as a "catalyst" for nucleation and subsequent new particle production in marine air.

9.
Nano Lett ; 24(22): 6601-6609, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38787739

RESUMO

Lead-halide perovskite nanocrystals (NCs) are promising for fabricating deep-blue (<460 nm) light-emitting diodes (LEDs), but their development is plagued by low electroluminescent performance and lead toxicity. Herein, the synthesis of 12 kinds of highly luminescent and eco-friendly deep-blue europium (Eu2+)-doped alkali-metal halides (AX:Eu2+; A = Na+, K+, Rb+, Cs+; X = Cl-, Br-, I-) NCs is reported. Through adjustment of the coordination environment, efficient deep-blue emission from Eu-5d → Eu-4f transitions is realized. The representative CsBr:Eu2+ NCs exhibit a high photoluminescence quantum yield of 91.1% at 441 nm with a color coordinate at (0.158, 0.023) matching with the Rec. 2020 blue specification. Electrically driven deep-blue LEDs from CsBr:Eu2+ NCs are demonstrated, achieving a record external quantum efficiency of 3.15% and half-lifetime of ∼1 h, surpassing the reported metal-halide deep-blue NCs-based LEDs. Importantly, large-area LEDs with an emitting area of 12.25 cm2 are realized with uniform emission, representing a milestone toward commercial display applications.

10.
J Am Chem Soc ; 146(1): 201-209, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38134356

RESUMO

Light, a nondestructive and remotely controllable external stimulus, effectively triggers a variety of electron-transfer phenomena in metal complexes. One prime example includes using light in molecular cyanide-bridged [FeCo] bimetallic Prussian blue analogues, where it switches the system between the electron-transferred metastable state and the system's ground state. If this process is coupled to a ferroelectric-type phase transition, the generation and disappearance of macroscopic polarization, entirely under light control, become possible. In this research, we successfully executed a nonpolar-to-polar phase transition in a trinuclear cyanide-bridged [Fe2Co] complex crystal via directional electron transfer. Intriguingly, by exposing the crystal to the wavelength of light─785 nm─without any electric field─we can drive this ferroelectric phase transition to completely depolarize the crystal, during which a measurable electric current response can be detected. These discoveries signify an important step toward the realization of fully light-controlled ferroelectric memory devices.

11.
Apoptosis ; 29(5-6): 835-848, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38573492

RESUMO

Oxaliplatin resistance poses a significant challenge in colorectal cancer (CRC) therapy, necessitating further investigation into the underlying molecular mechanisms. This study aimed to elucidate the regulatory role of SNHG4 in oxaliplatin resistance and ferroptosis in CRC. Our findings revealed that treatment with oxaliplatin led to downregulation of SNHG4 expression in CRC cells, while resistant CRC cells exhibited higher levels of SNHG4 compared to parental cells. Silencing SNHG4 attenuated oxaliplatin resistance and reduced the expression of resistance-related proteins MRD1 and MPR1. Furthermore, induction of ferroptosis effectively diminished oxaliplatin resistance in both parental and resistant CRC cells. Notably, ferroptosis induction resulted in decreased SNHG4 expression, whereas SNHG4 overexpression suppressed ferroptosis. Through FISH, RIP, and RNA pull-down assays, we identified the cytoplasmic localization of both SNHG4 and PTEN, establishing that SNHG4 directly targets PTEN, thereby reducing mRNA stability in CRC cells. Silencing PTEN abrogated the impact of SNHG4 on oxaliplatin resistance and ferroptosis in CRC cells. In vivo experiments further validated the influence of SNHG4 on oxaliplatin resistance and ferroptosis in CRC cells through PTEN regulation. In conclusion, SNHG4 promotes resistance to oxaliplatin in CRC cells by suppressing ferroptosis through instability of PTEN, thus serves as a target for patients with oxaliplatin-base chemoresistance.


Assuntos
Neoplasias Colorretais , Resistencia a Medicamentos Antineoplásicos , Ferroptose , Oxaliplatina , PTEN Fosfo-Hidrolase , Animais , Humanos , Camundongos , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Neoplasias Colorretais/genética , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/patologia , Neoplasias Colorretais/metabolismo , Resistencia a Medicamentos Antineoplásicos/genética , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Ferroptose/efeitos dos fármacos , Ferroptose/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Camundongos Nus , Oxaliplatina/farmacologia , PTEN Fosfo-Hidrolase/metabolismo , PTEN Fosfo-Hidrolase/genética , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto , Masculino
12.
Anal Chem ; 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39007441

RESUMO

G-quadruplex structures within the nuclear genome (nG4) is an important regulatory factor, while the function of G4 in the mitochondrial genome (mtG4) still needs to be explored, especially in human sperms. To gain a better understanding of the relationship between mtG4 and mitochondrial function, it is crucial to develop excellent probes that can selectively visualize and track mtG4 in both somatic cells and sperms. Herein, based on our previous research on purine frameworks, we attempted for the first time to extend the conjugated structure from the C-8 site of purine skeleton and discovered that the purine derivative modified by the C-8 aldehyde group is an ideal platform for constructing near-infrared probes with extremely large Stokes shift (>220 nm). Compared with the compound substituted with methylpyridine (PAP), the molecule substituted with methylthiazole orange (PATO) showed better G4 recognition ability, including longer emission (∼720 nm), more significant fluorescent enhancement (∼67-fold), lower background, and excellent photostability. PATO exhibited a sensitive response to mtG4 variation in both somatic cells and human sperms. Most importantly, PATO helped us to discover that mtG4 was significantly increased in cells with mitochondrial respiratory chain damage caused by complex I inhibitors (6-OHDA and rotenone), as well as in human sperms that suffer from oxidative stress. Altogether, our study not only provides a novel ideal molecular platform for constructing high-performance probes but also develops an effective tool for studying the relationship between mtG4 and mitochondrial function in both somatic cells and human sperms.

13.
Biochem Biophys Res Commun ; 711: 149894, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38603834

RESUMO

BACKGROUND: Low-grade glioma (LGG) has an extremely poor prognosis, and the mechanism leading to malignant development has not been determined. The aim of our study was to clarify the function and mechanism of anoikis and TIMP1 in the malignant progression of LGG. METHODS: We screened 7 anoikis-related genes from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases to construct a prognostic-predicting model. The study assessed the clinical prognosis, pathological characteristics, and immune cell infiltration in both high- and low-risk groups. Additionally, the potential modulatory effects of TIMP1 on proliferation, migration, and anoikis in LGG were investigated both in vivo and in vitro. RESULTS: In this study, we identified seven critical genes, namely, PTGS2, CCND1, TIMP1, PDK4, LGALS3, CDKN1A, and CDKN2A. Kaplan‒Meier (K‒M) curves demonstrated a significant correlation between clinical features and overall survival (OS), and single-cell analysis and mutation examination emphasized the heterogeneity and pivotal role of hub gene expression imbalances in LGG development. Immune cell infiltration and microenvironment analysis further elucidated the relationships between key genes and immune cells. In addition, TIMP1 promoted the malignant progression of LGG in both in vitro and in vivo models. CONCLUSIONS: This study confirmed that TIMP1 promoted the malignant progression of LGG by inhibiting anoikis, providing insights into LGG pathogenesis and potential therapeutic targets.


Assuntos
Anoikis , Glioma , Inibidor Tecidual de Metaloproteinase-1 , Humanos , Anoikis/genética , Glioma/genética , Glioma/imunologia , Glioma/patologia , Prognóstico , Inibidor Tecidual de Metaloproteinase-1/genética , Animais , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/imunologia , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/mortalidade , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Camundongos , Masculino , Proliferação de Células/genética , Feminino , Camundongos Nus , Microambiente Tumoral/genética , Microambiente Tumoral/imunologia , Gradação de Tumores
14.
Small ; : e2311087, 2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38335310

RESUMO

Herein, a type of light- and heat-driven flexible supramolecular polymer with reversibly long-lived phosphorescence and photochromism is constructed from acrylamide copolymers with 4-phenylpyridinium derivatives containing a cyano group (P-CN, P-oM, P-mM), sulfobutylether-ß-cyclodextrin (SBCD), and polyvinyl alcohol (PVA). Compared to their parent solid polymers, these flexible supramolecules based on the non-covalent cross-linking of copolymers, SBCD, and PVA efficiently boost the phosphorescence lifetimes (723.0 ms for P-CN, 623.0 ms for P-oM, 945.8 ms for P-mM) through electrostatic interaction and hydrogen bonds. The phosphorescence intensity/lifetime, showing excellent responsiveness to light and heat, sharply decreased after irradiation with a 275 nm flashlight or sunlight and gradually recovered through heating. This is accompanied by the occurrence and fading of visible photochromism, manifesting as dark green for P-CN and pink for P-oM and P-mM. These reversible photochromism and phosphorescence behaviors are mainly attributed to the generation and disappearance of organic radicals in the 4-phenylpyridinium derivatives with a cyano group, which can guide tunable luminescence and photochromism.

15.
Int J Obes (Lond) ; 48(6): 849-858, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38341506

RESUMO

OBJECTIVE: Fatty acids play a critical role in the proper functioning of the brain. This study investigated the effects of a high-fat (HF) diet on brain fatty acid profiles of offspring exposed to maternal gestational diabetes mellitus (GDM). METHODS: Insulin receptor antagonist (S961) and HF diet were used to establish the GDM animal model. Brain fatty acid profiles of the offspring mice were measured by gas chromatography at weaning and adulthood. Protein expressions of the fatty acid transport pathway Wnt3/ß-catenin and the target protein major facilitator superfamily domain-containing 2a (MFSD2a) were measured in the offspring brain by Western blot. RESULTS: Maternal GDM increased the body weight of male offspring (P < 0.05). In weaning offspring, factorial analysis showed that maternal GDM increased the monounsaturated fatty acid (MUFA) percentage of the weaning offspring's brain (P < 0.05). Maternal GDM decreased offspring brain arachidonic acid (AA), but HF diet increased brain linoleic acid (LA) (P < 0.05). Maternal GDM and HF diet reduced offspring brain docosahexaenoic acid (DHA), and the male offspring had higher DHA than the female offspring (P < 0.05). In adult offspring, factorial analysis showed that HF diet increased brain MUFA in offspring, and male offspring had higher brain MUFA than female offspring (P < 0.05). The HF diet increased brain LA in the offspring. Male offspring had higher level of AA than female offspring (P < 0.05). HF diet reduced DHA in the brains of female offspring. The brain protein expression of ß-catenin and MFSD2a in both weaning and adult female offspring was lower in the HF + GDM group than in the CON group (P < 0.05). CONCLUSIONS: Maternal GDM increased the susceptibility of male offspring to HF diet-induced obesity. HF diet-induced adverse brain fatty acid profiles in both male and female offspring exposed to GDM.


Assuntos
Encéfalo , Diabetes Gestacional , Dieta Hiperlipídica , Ácidos Graxos , Efeitos Tardios da Exposição Pré-Natal , Animais , Gravidez , Feminino , Diabetes Gestacional/metabolismo , Camundongos , Dieta Hiperlipídica/efeitos adversos , Encéfalo/metabolismo , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Masculino , Ácidos Graxos/metabolismo , Modelos Animais de Doenças , Fenômenos Fisiológicos da Nutrição Materna
16.
Opt Express ; 32(6): 10059-10067, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38571226

RESUMO

Dissipative solitons (DSs), due to the complex interplay among dispersion, nonlinear, gain and loss, illustrate abundant nonlinear dynamics behaviors. Especially, dispersion plays an important role in the research of DS dynamics in ultrafast fiber lasers. Previous studies have mainly focused on the effect of even-order dispersion, i.e., group velocity dispersion (GVD) and fourth-order dispersion. In fact, odd-order dispersions, such as third-order dispersion (TOD), also significantly influences the dynamics of DSs. However, due to the lack of dispersion engineering tools, few experimental researches in this domain have been reported. In this work, by employing a pulse shaper in ultrafast fiber laser, an in-depth exploration of the DS dynamics influenced by TOD was conducted. With the increase of TOD value, the stable single DS undergoes a splitting into two solitons and then enters explosion state, and ultimately evolves into a chaotic state. The laser operation state is correlated to dispersion profile, which could be controlled by TOD. Here, the positive dispersion at long-wavelength side will be gradually shifted to negative dispersion by increasing the TOD, where soliton effect will drive the transitions. These findings offer valuable insights into the nonlinear dynamics of ultrafast lasers and may also foster applications involving higher-order dispersion.

17.
Opt Express ; 32(3): 4427-4435, 2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38297644

RESUMO

Multimode fiber lasers have become a new platform for investigating nonlinear phenomena since the report on spatiotemporal mode-locking. In this work, the multimode soliton pulsation with a tunable period is achieved in a spatiotemporal mode-locked fiber laser. It demonstrates that the pulsation period drops while increasing the pump power. Moreover, it is found that different transverse modes have the same pulsation period, asynchronous pulsation evolution and different dynamical characteristics through the spatial sampling technique and the dispersive Fourier transform technique. To further verify the experimental results, we numerically investigate the influences of the gain and the loss on the pulsation properties. It is found that within a certain parameter range, the pulsation period drops and rises linearly with the increase of the gain and the loss, respectively. The obtained results contribute to understanding the formation and regulating of soliton pulsations in fiber lasers.

18.
Opt Lett ; 49(1): 57-60, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38134151

RESUMO

We develop an all polarization-maintaining (PM) 920 nm Nd-doped fiber amplifier delivering a train of pulses with ∼0.53 W average power and sub-50 fs duration. The sub-50 fs pulse benefits from the pre-chirping management method that allows for over 60 nm broadening spectrum without pulse breaking in the amplification stage. By virtue of the short pulse duration, the pulse peak power can reach to ∼0.31 MW in spite of the moderate average power. These results represent a key step in developing high-peak-power pulse Nd-doped fiber laser systems at 920 nm, which will find important applications in fields such as biomedical imaging, ultrafast optical spectroscopy, and excitation of quantum-dot single photon sources.

19.
Opt Lett ; 49(6): 1575-1578, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38489454

RESUMO

Spatiotemporal mode-locked (STML) fiber lasers have become a new platform for investigating nonlinear phenomena. In this work, spatiotemporal dual-periodic soliton pulsation (SDSP) is firstly observed in an STML fiber laser. It is found that in the SDSP, the long-period pulsations (LPPs) of different transverse modes are synchronous, while the short-period pulsations (SPPs) exhibit asynchronous modulations. The numerical simulation confirms the experimental results and further reveals that the proportion of transverse mode components can manipulate the periods of the LPP and SPP but does not affect the synchronous and asynchronous pulsations of different transverse modes. The obtained results bring the study of spatiotemporal dissipative soliton pulsation into the multi-period modulation stage, which helps to understand the complex spatiotemporal dynamics in STML fiber lasers and discover new dynamics in high-dimensional nonlinear systems.

20.
Chemistry ; : e202401805, 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38752446

RESUMO

The second near-infrared window (NIR-II, 1000-1700 nm) fluorescence imaging has attracted significant attention in research fields because of its unique advantages compared with conventional optical windows (400-900 nm). A variety of NIR-II fluorophores have been actively studied because they serve as a key component of fluorescence imaging. Among them, organic small molecule NIR-II fluorophores display outstanding imaging performance and many advantages, but types of small molecule NIR-II fluorophores with high biocompatibility are still quite limited. Novel molecular scaffolds based NIR-II dyes are highly desired. Herein, we hypothesized that chlorophyll is a new promising molecular platform for discovery NIR-II fluorophores. Thus, seven derivatives of derivatives were selected to characterize their optical properties. Interestingly, six chlorophyll derivatives displayed NIR-II fluorescence imaging capability. This characteristic allowed the successful NIR-II imaging of green leaves of various plants. Furthermore, most of these fluorophores showed capacity to monitor viscosity change because of their sensitive for viscosity. For demonstration of its biomedical applications, these probes were successfully used for NIR-II fluorescence-guided surgical resection of lymph nodes. In summary, chlorophylls are novel valuable tool molecules for NIR-II fluorescence imaging and have potential to expand their applications in biomedical field and plant science.

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