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1.
Sensors (Basel) ; 24(12)2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38931647

RESUMO

In this paper, the kinematic models of the Strapdown Inertial Navigation System (SINS) and its errors on the SE(3) group in the Earth-Centered Inertial frame (ECI) are established. On the one hand, with the ECI frame being regarded as the reference, based on the joint representation of attitude and velocity on the SE(3) group, the dynamic of the local geographic coordinate system (n-frame) and the body coordinate system (b-frame) evolve on the differentiable manifold, respectively, and the high-order expansion of the Baker-Campbell-Haussdorff equation compensates for the non-commutative motion errors stimulated by strong maneuverability. On the other hand, the kinematics of the left- and right-invariant errors of the n-frame and the b-frame on the SE(3) group are separately derived, where the errors of the b-frame completely depend on inertial sensor errors, while the errors of the n-frame rely on position errors and velocity errors. In this way, the errors brought by the inconsistency of the reference coordinate system are tackled, and a novel attitude error definition is introduced to separate and decouple the factors affecting the dynamic of the n-frame errors and the b-frame errors for better attitude estimation. Through a turntable experiment and a car-mounted field experiment, the effectiveness of the proposed kinematic models in estimating attitude has been verified, with a remarkable improvement in yaw angle accuracy in the case of large initial misalignment angles, and the models developed have better robustness compared to the traditional SE(3) group-based model.

2.
Environ Res ; 258: 119411, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38876423

RESUMO

Epidemiological evidence on the impact of airborne organic pollutants on lung function among the elderly is limited, and their underlying biological mechanisms remain largely unexplored. Herein, a longitudinal panel study was conducted in Jinan, Shandong Province, China, involving 76 healthy older adults monitored over a span of five months repetitively. We systematically evaluated personal exposure to a diverse range of airborne organic pollutants using a wearable passive sampler and their effects on lung function. Participants' pulmonary function indicators were assessed, complemented by comprehensive multi-omics analyses of blood and urine samples. Leveraging the power of interaction analysis, causal inference test (CIT), and integrative pathway analysis (IPA), we explored intricate relationships between specific organic pollutants, biomolecules, and lung function deterioration, elucidating the biological mechanisms underpinning the adverse impacts of these pollutants. We observed that bis (2-chloro-1-methylethyl) ether (BCIE) was significantly associated with negative changes in the forced vital capacity (FVC), with glycerolipids mitigating this adverse effect. Additionally, 31 canonical pathways [e.g., high mobility group box 1 (HMGB1) signaling, phosphatidylinositol 3-kinase (PI3K)/AKT pathway, epithelial mesenchymal transition, and heme and nicotinamide adenine dinucleotide (NAD) biosynthesis] were identified as potential mechanisms. These findings may hold significant implications for developing effective strategies to prevent and mitigate respiratory health risks arising from exposure to such airborne pollutants. However, due to certain limitations of the study, our results should be interpreted with caution.

3.
J Am Chem Soc ; 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38843049

RESUMO

The development of a catalytic method for stereogenic carbon center formation holds immense significance in organic synthesis. Transition-metal-catalyzed cross-coupling reaction has been regarded as a straightforward and efficient tool for stereoselectively forging C-C bond. Nevertheless, the creation of acyclic all-carbon quaternary-containing vicinal stereocenters remains notoriously challenging within the domain of cross-coupling chemistry despite their prominence in various bioactive small molecules. Herein, we describe a palladium-catalyzed asymmetric multicomponent cross-coupling of trisubstituted alkene with aryl diazonium salts and arylboronic acids to realize the formation of tertiary-quaternary carbon centers with high regio-, distereo-, and enantioselectivity. Specifically, the precise manipulation of the stereoconfiguration of trisubstituted alkenes enables the divergent stereoselective cross-coupling reaction, thus allowing for the facile construction of all four enantiomers. Harnessing the ligand-swap strategy involving a chiral bisoxazoline and an achiral fumarate individually accelerates the enantioselective migratory insertion and reductive elimination step in the cross-coupling process, as supported by density functional theory (DFT) calculations, thus obviating the requirement for a neighboring directing group within the internal olefin skeleton.

4.
Zhonghua Wei Zhong Bing Ji Jiu Yi Xue ; 36(4): 415-421, 2024 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-38813638

RESUMO

OBJECTIVE: To investigate the establishment method, coordination points and safe transport management strategy of vena-arterial extracorporeal membrane oxygenation (VA-ECMO) in patients with downtime difficulties during cardiopulmonary bypass (CPB). METHODS: A observation study was conducted. The patients admitted to the department of critical care medicine of the First Affiliated Hospital of Wannan Medical College (Yijishan Hospital) from January 2020 to October 2022 were enrolled. These patients could not be separated from CPB and received VA-ECMO-assisted CPB surgery. The clinical data of the patients were recorded, including the basic information of the patients, the data of VA-ECMO establishment and transport process, the clinical indicators before and after VA-ECMO installation, the operation data of VA-ECMO and clinical outcomes. The experience was summarized from the aspects of extracorporeal membrane oxygenation (ECMO) establishment, transport process, team cooperation, and adverse events during transport. The clinical indicators before and after ECMO operation were compared. According to whether ECMO was successfully weaned, the patients were divided into a successful weaning group and a failure weaning group, and the clinical data between the two groups were compared. RESULTS: Eighteen patients who underwent VA-ECMO-assisted CPB were enrolled, including 10 males and 8 females. The average age was (56.7±12.3) years old. Preoperative left ventricular ejection fraction (LVEF) was 0.46±0.10, and the main reasons for switching to VA-ECMO assistance included right ventricular systolic weakness in 6 cases, total cardiac systolic weakness in 5 cases, left ventricular systolic weakness in 4 cases, high pulmonary arterial pressure in 2 cases, and intractable ventricular fibrillation in 1 case. Among the 18 patients transferred from CPB to VA-ECMO, 10 cases were successfully weaned and 8 cases failed. In ICU, 8 cases survived, 5 cases died, and 5 cases gave up treatment and discharged. The average time for successful CPB to VA-ECMO establishment was (24.6±7.4) minutes, initial blood flow was (3.3±0.4) L/min, and transit time was (8.4±1.5) minutes. ECMO-assisted duration averaged (82.0±69.3) hours. Adverse events occurred in 9 patients during ECMO establishment and transfer. Post-ECMO onboarding for 4 hours, significant improvements were noted in blood lactic acid (Lac), pH value, mean arterial pressure (MAP), central venous oxygen saturation (ScvO2) as compared with pre-ECMO onboarding [Lac (mmol/L): 10.5±7.0 vs. 15.2±6.8, pH value: 7.38±0.92 vs. 7.26±0.87, MAP (mmHg, 1 mmHg ≈ 0.133 kPa): 74.9±13.7 vs. 58.4±17.0, ScvO2: 0.678±0.065 vs. 0.611±0.061, all P < 0.01], and vasoactive-inotropic score (VIS) was also decreased (39.8±29.8 vs. 68.9±64.4, P < 0.01). Compared with successful weaning group, the patients in the failed weaning group exhibited higher pre-machine Lac (mmol/L: 18.8±7.8 vs. 12.3±4.3, P < 0.05), longer CPB time [minutes: 238.0 (208.8, 351.2) vs. 200.0 (185.8, 217.0), P < 0.05], and shorter ECMO-assisted time [hours: 19.5 (11.0, 58.8) vs. 94.5 (65.8, 179.8), P < 0.01]. However, there was no statistically significant difference in pre-machine pH value, ScvO2, MAP, VIS score, and initial blood flow and establishment time of ECMO between the two groups. CONCLUSIONS: VA-ECMO is an effective circulatory aid for CPB surgery that cannot be weaned after CPB. The establishment and transfer of CPB "bridge" to ECMO aid depends on multi-disciplinary treatment (MDT) cooperation. The success rate of ECMO weaning is related to the Lac and CPB duration. If it is not possible to detach from the CPB successfully, VA-ECMO should be initiated as early as possible.


Assuntos
Ponte Cardiopulmonar , Oxigenação por Membrana Extracorpórea , Humanos , Oxigenação por Membrana Extracorpórea/métodos , Ponte Cardiopulmonar/métodos , Feminino , Masculino , Pessoa de Meia-Idade
5.
Opt Lett ; 49(10): 2785-2788, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38748161

RESUMO

Single-molecule localization microscopy (SMLM) enables three-dimensional (3D) super-resolution imaging of nanoscale structures within biological samples. However, prolonged acquisition introduces a drift between the sample and the imaging system, resulting in artifacts in the reconstructed super-resolution image. Here, we present a novel, to our knowledge, 3D drift correction method that utilizes both the reflected and scattered light from the sample. Our method employs the reflected light of a near-infrared (NIR) laser for focus stabilization while synchronously capturing speckle images to estimate the lateral drift. This approach combines high-precision active compensation in the axial direction with lateral post-processing compensation, achieving the abilities of 3D drift correction with a single laser light. Compared to the popular localization events-based cross correlation method, our approach is much more robust, especially for datasets with sparse localization points.

6.
Plant Cell Environ ; 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38736429

RESUMO

Day length modulates hypocotyl elongation in seedlings to optimize their overall fitness. Variations in cell growth-associated genes are regulated by several transcription factors. However, the specific transcription factors through which the plant clock increases plant fitness are still being elucidated. In this study, we identified the no apical meristem, Arabidopsis thaliana-activating factor (ATAF-1/2), and cup-shaped cotyledon (NAC) family transcription factor ATAF1 as a novel repressor of hypocotyl elongation under a short-day (SD) photoperiod. Variations in day length profoundly affected the transcriptional and protein levels of ATAF1. ATAF1-deficient mutant exhibited increased hypocotyl length and cell growth-promoting gene expression under SD conditions. Moreover, ATAF1 directly targeted and repressed the expression of the cycling Dof factor 1/5 (CDF1/5), two key transcription factors involved in hypocotyl elongation under SD conditions. Additionally, ATAF1 interacted with and negatively modulated the effects of phytochrome-interacting factor (PIF), thus inhibiting PIF-promoted gene expression and hypocotyl elongation. Taken together, our results revealed ATAF1-PIF as a crucial pair modulating the expression of key transcription factors to facilitate plant growth during day/night cycles under fluctuating light conditions.

7.
Cereb Cortex ; 34(5)2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38725291

RESUMO

A widely used psychotherapeutic treatment for post-traumatic stress disorder (PTSD) involves performing bilateral eye movement (EM) during trauma memory retrieval. However, how this treatment-described as eye movement desensitization and reprocessing (EMDR)-alleviates trauma-related symptoms is unclear. While conventional theories suggest that bilateral EM interferes with concurrently retrieved trauma memories by taxing the limited working memory resources, here, we propose that bilateral EM actually facilitates information processing. In two EEG experiments, we replicated the bilateral EM procedure of EMDR, having participants engaging in continuous bilateral EM or receiving bilateral sensory stimulation (BS) as a control while retrieving short- or long-term memory. During EM or BS, we presented bystander images or memory cues to probe neural representations of perceptual and memory information. Multivariate pattern analysis of the EEG signals revealed that bilateral EM enhanced neural representations of simultaneously processed perceptual and memory information. This enhancement was accompanied by heightened visual responses and increased neural excitability in the occipital region. Furthermore, bilateral EM increased information transmission from the occipital to the frontoparietal region, indicating facilitated information transition from low-level perceptual representation to high-level memory representation. These findings argue for theories that emphasize information facilitation rather than disruption in the EMDR treatment.


Assuntos
Eletroencefalografia , Dessensibilização e Reprocessamento através dos Movimentos Oculares , Humanos , Feminino , Masculino , Adulto Jovem , Adulto , Dessensibilização e Reprocessamento através dos Movimentos Oculares/métodos , Movimentos Oculares/fisiologia , Transtornos de Estresse Pós-Traumáticos/fisiopatologia , Transtornos de Estresse Pós-Traumáticos/terapia , Transtornos de Estresse Pós-Traumáticos/psicologia , Percepção Visual/fisiologia , Memória/fisiologia , Encéfalo/fisiologia , Estimulação Luminosa/métodos , Memória de Curto Prazo/fisiologia
8.
EMBO J ; 43(10): 1965-1989, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38605224

RESUMO

The transition of mouse embryonic stem cells (ESCs) between serum/LIF and 2i(MEK and GSK3 kinase inhibitor)/LIF culture conditions serves as a valuable model for exploring the mechanisms underlying ground and confused pluripotent states. Regulatory networks comprising core and ancillary pluripotency factors drive the gene expression programs defining stable naïve pluripotency. In our study, we systematically screened factors essential for ESC pluripotency, identifying TEAD2 as an ancillary factor maintaining ground-state pluripotency in 2i/LIF ESCs and facilitating the transition from serum/LIF to 2i/LIF ESCs. TEAD2 exhibits increased binding to chromatin in 2i/LIF ESCs, targeting active chromatin regions to regulate the expression of 2i-specific genes. In addition, TEAD2 facilitates the expression of 2i-specific genes by mediating enhancer-promoter interactions during the serum/LIF to 2i/LIF transition. Notably, deletion of Tead2 results in reduction of a specific set of enhancer-promoter interactions without significantly affecting binding of chromatin architecture proteins, CCCTC-binding factor (CTCF), and Yin Yang 1 (YY1). In summary, our findings highlight a novel prominent role of TEAD2 in orchestrating higher-order chromatin structures of 2i-specific genes to sustain ground-state pluripotency.


Assuntos
Cromatina , Proteínas de Ligação a DNA , Células-Tronco Embrionárias Murinas , Fatores de Transcrição de Domínio TEA , Fatores de Transcrição , Animais , Camundongos , Fatores de Transcrição de Domínio TEA/metabolismo , Cromatina/metabolismo , Cromatina/genética , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Proteínas de Ligação a DNA/metabolismo , Proteínas de Ligação a DNA/genética , Células-Tronco Embrionárias Murinas/metabolismo , Células-Tronco Embrionárias Murinas/citologia , Células-Tronco Pluripotentes/metabolismo , Células-Tronco Pluripotentes/citologia , Regiões Promotoras Genéticas , Elementos Facilitadores Genéticos
9.
Sci Rep ; 14(1): 8324, 2024 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-38594513

RESUMO

Bladder cancer (BLCA) is a common malignant tumor in urinary system all over the world. However, due to its high recurrence rate and complex causes, clinicians often have limited options for surgical and drug treatments. Recent researchs on the molecular mechanism of BLCA have reveals its biological progress and potential for early diagnosis. Serine hydroxymethyltransferase 1/2 (SHMT1/2) is a crucial enzyme in the one-carbon metabolism of tumor cells, and the expression levels of these isozymes have been found to be associated with the biological progression of various malignant tumors. However, the impact of SHMT1/2 on the biological progression of bladder cancer and its molecular regulation mechanism remain unclear. In this research utilizes BLCA clinical sample data, the TCGA database, and in vitro cell experiments to predict the expression levels of SHMT1/2 in BLCA. The findings indicate that SHMT1 remained unchanged, while SHMT2 expression is increased in BLCA, which was related to poor prognosis. Additionally, SHMT2 affects the growth, migration, and apoptosis of bladder cancer cells in vitro. It also influences the expression levels of E-cadherin and N-cadherin, ultimately impacting the malignant biological progression of bladder tumors. These results establish a correlation between SHMT2 and the malignant biological progression of BLCA, providing a theoretical basis for the early diagnosis and treatment of bladder cancer.


Assuntos
Glicina Hidroximetiltransferase , Neoplasias da Bexiga Urinária , Humanos , Glicina Hidroximetiltransferase/genética , Neoplasias da Bexiga Urinária/metabolismo , Serina/metabolismo , Prognóstico
10.
Phys Rev E ; 109(3-2): 035205, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38632769

RESUMO

The double-cone ignition (DCI) scheme has been proposed as one of the alternative approaches to inertial confinement fusion, based on direct-drive and fast-ignition, in order to reduce the requirement for the driver energy. To evaluate the conical implosion energetics from the laser beams to the plasma flows, a series of experiments have been systematically conducted. The results indicate that 89%-96% of the laser energy was absorbed by the target, with moderate stimulated Raman scatterings. Here 2%-6% of the laser energy was coupled into the plasma jets ejected from the cone tips, which was mainly restricted by the mass reductions during the implosions inside the cones. The supersonic dense jets with a Mach number of 4 were obtained, which is favorable for forming a high-density, nondegenerated plasma core after the head-on collisions. These findings show encouraging results in terms of energy transport of the conical implosions in the DCI scheme.

11.
Sci Adv ; 10(6): eadj5778, 2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38324680

RESUMO

Effectively reducing climate change requires marked, global behavior change. However, it is unclear which strategies are most likely to motivate people to change their climate beliefs and behaviors. Here, we tested 11 expert-crowdsourced interventions on four climate mitigation outcomes: beliefs, policy support, information sharing intention, and an effortful tree-planting behavioral task. Across 59,440 participants from 63 countries, the interventions' effectiveness was small, largely limited to nonclimate skeptics, and differed across outcomes: Beliefs were strengthened mostly by decreasing psychological distance (by 2.3%), policy support by writing a letter to a future-generation member (2.6%), information sharing by negative emotion induction (12.1%), and no intervention increased the more effortful behavior-several interventions even reduced tree planting. Last, the effects of each intervention differed depending on people's initial climate beliefs. These findings suggest that the impact of behavioral climate interventions varies across audiences and target behaviors.


Assuntos
Ciências do Comportamento , Mudança Climática , Humanos , Intenção , Políticas
12.
Animals (Basel) ; 14(3)2024 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-38338152

RESUMO

Flexible turning behavior endows Homing Pigeons (Columba livia domestica) with high adaptability and intelligence in long-distance flight, foraging, hazard avoidance, and social interactions. The present study recorded the activity pattern of their local field potential (LFP) oscillations and explored the relationship between different bands of oscillations and turning behaviors in the formatio reticularis medialis mesencephali (FRM). The results showed that the C (13-60 Hz) and D (61-130 Hz) bands derived from FRM nuclei oscillated significantly in active turning, while the D and E (131-200 Hz) bands oscillated significantly in passive turning. Additionally, compared with lower-frequency stimulation (40 Hz and 60 Hz), 80 Hz stimulation can effectively activate the turning function of FRM nuclei. Electrical stimulation elicited stronger oscillations of neural activity, which strengthened the pigeons' turning locomotion willingness, showing an enhanced neural activation effect. These findings suggest that different band oscillations play different roles in the turning behavior; in particular, higher-frequency oscillations (D and E bands) enhance the turning behavior. These findings will help us decode the complex relationship between bird brains and behaviors and are expected to facilitate the development of neuromodulation techniques for animal robotics.

13.
Artigo em Inglês | MEDLINE | ID: mdl-38299400

RESUMO

BACKGROUND AND OBJECTIVE: Understanding the regulatory mechanisms involving neuronatin (NNAT) in non-small cell lung cancer (NSCLC) is an ongoing challenge. This study aimed to elucidate the impact of NNAT knockdown on NSCLC by employing both in vitro and in vivo approaches. METHODS: To investigate the role of NNAT, its expression was silenced in NSCLC cell lines A549 and H226. Subsequently, various parameters, including cell proliferation, invasion, migration, and apoptosis, were assessed. Additionally, cell-derived xenograft models were established to evaluate the effect of NNAT knockdown on tumor growth. The expression of key molecules, including cyclin D1, B-cell leukemia/lymphoma 2 (Bcl-2), p65, matrix metalloproteinase (MMP) 2, and nerve growth factor (NGF) were examined both in vitro and in vivo. Nerve fiber density within tumor tissues was analyzed using silver staining. RESULTS: Upon NNAT knockdown, a remarkable reduction in NSCLC cell proliferation, invasion, and migration was observed, accompanied by elevated levels of apoptosis. Furthermore, the expression of cyclin D1, Bcl-2, MMP2, and phosphorylated p65 (p-p65) showed significant downregulation. In vivo, NNAT knockdown led to substantial inhibition of tumor growth and a concurrent decrease in cyclinD1, Bcl-2, MMP2, and p-p65 expression within tumor tissues. Importantly, NNAT knockdown also led to a decrease in nerve fiber density and downregulation of NGF expression within the xenograft tumor tissues. CONCLUSION: Collectively, these findings suggest that neuronatin plays a pivotal role in driving NSCLC progression, potentially through the activation of the nuclear factor-kappa B signaling cascade. Additionally, neuronatin may contribute to the modulation of tumor microenvironment innervation in NSCLC. Targeting neuronatin inhibition emerges as a promising strategy for potential anti-NSCLC therapeutic intervention.

14.
World J Gastroenterol ; 30(5): 485-498, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38414591

RESUMO

BACKGROUND: Gastric cancer (GC) is associated with high mortality rates. Bile acids (BAs) reflux is a well-known risk factor for GC, but the specific mechanism remains unclear. During GC development in both humans and animals, BAs serve as signaling molecules that induce metabolic reprogramming. This confers additional cancer phenotypes, including ferroptosis sensitivity. Ferroptosis is a novel mode of cell death characterized by lipid peroxidation that contributes universally to malignant progression. However, it is not fully defined if BAs can influence GC progression by modulating ferroptosis. AIM: To reveal the mechanism of BAs regulation in ferroptosis of GC cells. METHODS: In this study, we treated GC cells with various stimuli and evaluated the effect of BAs on the sensitivity to ferroptosis. We used gain and loss of function assays to examine the impacts of farnesoid X receptor (FXR) and BTB and CNC homology 1 (BACH1) overexpression and knockdown to obtain further insights into the molecular mechanism involved. RESULTS: Our data suggested that BAs could reverse erastin-induced ferroptosis in GC cells. This effect correlated with increased glutathione (GSH) concentrations, a reduced GSH to oxidized GSH ratio, and higher GSH peroxidase 4 (GPX4) expression levels. Subsequently, we confirmed that BAs exerted these effects by activating FXR, which markedly increased the expression of GSH synthetase and GPX4. Notably, BACH1 was detected as an essential intermediate molecule in the promotion of GSH synthesis by BAs and FXR. Finally, our results suggested that FXR could significantly promote GC cell proliferation, which may be closely related to its anti-ferroptosis effect. CONCLUSION: This study revealed for the first time that BAs could inhibit ferroptosis sensitivity through the FXR-BACH1-GSH-GPX4 axis in GC cells. This work provided new insights into the mechanism associated with BA-mediated promotion of GC and may help identify potential therapeutic targets for GC patients with BAs reflux.


Assuntos
Ferroptose , Neoplasias Gástricas , Animais , Humanos , Ácidos e Sais Biliares , Transdução de Sinais
15.
Protein Cell ; 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38167949

RESUMO

Polycystic ovary syndrome (PCOS) is the leading cause of anovulatory infertility. Inadequate understanding of the ovulation drivers hinders PCOS intervention. Herein, we report that follicle stimulating hormone (FSH) controls follicular fluid (FF) glutamine levels to determine ovulation. Murine ovulation starts from FF-exposing granulosa cell (GC) apoptosis. FF glutamine, which decreases in pre-ovulation porcine FF, elevates in PCOS patients FF. High-glutamine chow to elevate FF glutamine inhibits mouse GC apoptosis and induces hormonal, metabolic, and morphologic PCOS traits. Mechanistically, follicle-development-driving FSH promotes GC glutamine synthesis to elevate FF glutamine, which maintain follicle wall integrity by inhibiting GC apoptosis through inactivating ASK1-JNK apoptotic pathway. FSH and glutamine inhibit rapture of cultured murine follicles. Glutamine removal or ASK1-JNK pathway activation with metformin or AT-101 reversed PCOS traits in PCOS models that are induced with either glutamine or EsR1-KO. These suggest that glutamine, FSH and ASK1-JNK pathway are targetable to alleviate PCOS.

16.
Rapid Commun Mass Spectrom ; 38(3): e9669, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38211350

RESUMO

RATIONALE: Sinomenine, a major bioactive compound isolated from Sinomenium acutum, has been used for the treatment of rheumatoid arthritis and other cardio-cerebrovacular diseases. However, the metabolism of this drug has not been fully investigated. The current work was carried out to investigate the in vitro metabolism of sinomenine in liver microsomes. METHODS: The metabolites were generated by incubating sinomenine (3 µM) with the liver microsomes in the presence of NADPH at 37°C. The structure of the metabolites was characterized using liquid chromatography coupled to high-resolution mass spectrometry (HRMS). Two major metabolites synthesized and their structures were further confirmed using nuclear magnetic resonance spectroscopy. RESULTS: Under the current conditions, 12 metabolites were found and structurally identified using high resolution MS and MS2 spectra. Among these metabolites, M1, M2, M3, M4, M5, M6, M7, M9, M11, and M12 were first reported. The metabolites M8 and M10 were synthesized and unambiguously identified as N-desmethyl-sinomenine and sinomenine N-oxide, respectively. The phenotyping study revealed that the formation of M8 was catalyzed by CYP2C8, 2C19, 2D6, and 3A4, whereas the formation of M3, M6, and M10 were exclusively catalyzed by CYP3A4. The metabolic pathways of sinomenine include N-demethylation, O-demethylation, dehydrogenation, oxygenation, and N-oxygenation. CONCLUSIONS: N-Demethylation and N-oxygenation were the primary metabolic pathways of sinomenine. This study provides new insight into the in vitro metabolism of sinomenine, which would help prospects of sinomenine disposition and safety assessments.


Assuntos
Microssomos Hepáticos , Morfinanos , Espectrometria de Massas/métodos , Cromatografia Líquida , Espectroscopia de Ressonância Magnética , Microssomos Hepáticos/metabolismo , Cromatografia Líquida de Alta Pressão/métodos
17.
J Agric Food Chem ; 72(2): 1190-1202, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38175798

RESUMO

10-Hydroxy-2-decenoic acid (10-HDA) is an important component of royal jelly, known for its antimicrobial, anti-inflammatory, blood pressure-lowering, and antiradiation effects. Currently, 10-HDA biosynthesis is limited by the substrate selectivity of acyl-coenzyme A dehydrogenase, which restricts the technique to a two-step process. This study aimed to develop an efficient and simplified method for synthesizing 10-HDA. In this study, ACOX from Candida tropicalis 1798, which catalyzes 10-hydroxydecanoyl coenzyme A desaturation for 10-HDA synthesis, was isolated and heterologously coexpressed with FadE, Macs, YdiI, and CYP in Escherichia coli/SK after knocking out FadB, FadJ, and FadR genes. The engineered E. coli/AKS strain achieved a 49.8% conversion of decanoic acid to 10-HDA. CYP expression was improved through ultraviolet mutagenesis and high-throughput screening, increased substrate conversion to 75.6%, and the synthesis of 10-HDA was increased to 0.628 g/L in 10 h. This is the highest conversion rate and product concentration achieved in the shortest time to date. This study provides a simple and efficient method for 10-HDA biosynthesis and offers an effective method for developing strains with high product yields.


Assuntos
Escherichia coli , Ácidos Graxos Monoinsaturados , Escherichia coli/genética , Escherichia coli/metabolismo , Ácidos Graxos Monoinsaturados/metabolismo , Ácidos Graxos/metabolismo , Anti-Inflamatórios
18.
Phytomedicine ; 124: 155268, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38176265

RESUMO

BACKGROUND: Obesity has emerged as a global epidemic. Recent research has indicated that diet-induced obesity can be prevented by promoting lacteal junction zippering. Berberine, which is derived from natural plants, is found to be promising in weight reduction, but the underlying mechanism remains unspecified. PURPOSE: To determine whether berberine protects against obesity by regulating the lacteal junction and to explore potential molecular mechanisms. METHODS: Following the induction of the diet-induced obese (DIO) model, mice were administered low and high doses of berberine for 4 weeks. Indicators associated with insulin resistance and lipid metabolism were examined. Various methods, such as Oil Red O staining, transmission electron microscopy imaging, confocal imaging and others were used to observe the effects of berberine on lipid absorption and the lacteal junction. In vitro, human dermal lymphatic endothelial cells (HDLECs) were used to investigate the effect of berberine on LEC junctions. Western Blot and immunostaining were applied to determine the expression levels of relevant molecules. RESULTS: Both low and high doses of berberine reduced body weight in DIO mice without appetite suppression and ameliorated glucolipid metabolism disorders. We also found that the weight loss effect of berberine might contribute to the inhibition of small intestinal lipid absorption. The possible mechanism was related to the promotion of lacteal junction zippering via suppressing the ras homolog gene family member A (RhoA)/Rho-associated kinase (ROCK) signaling pathway. In vitro, berberine also promoted the formation of stable mature junctions in HDLECs, involving the same signaling pathway. CONCLUSION: Berberine could promote lacteal junction zippering and ameliorate diet-induced obesity through the RhoA/ROCK signaling pathway.


Assuntos
Berberina , Camundongos , Humanos , Animais , Berberina/farmacologia , Células Endoteliais/metabolismo , Transdução de Sinais , Obesidade/tratamento farmacológico , Dieta , Lipídeos , Proteína rhoA de Ligação ao GTP/metabolismo
19.
Cancer Res ; 84(5): 659-674, 2024 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-38190710

RESUMO

Epithelial-mesenchymal transition (EMT) is a fundamental cellular process frequently hijacked by cancer cells to promote tumor progression, especially metastasis. EMT is orchestrated by a complex molecular network acting at different layers of gene regulation. In addition to transcriptional regulation, posttranscriptional mechanisms may also play a role in EMT. Here, we performed a pooled CRISPR screen analyzing the influence of 1,547 RNA-binding proteins on cell motility in colon cancer cells and identified multiple core components of P-bodies (PB) as negative modulators of cancer cell migration. Further experiments demonstrated that PB depletion by silencing DDX6 or EDC4 could activate hallmarks of EMT thereby enhancing cell migration in vitro as well as metastasis formation in vivo. Integrative multiomics analysis revealed that PBs could repress the translation of the EMT driver gene HMGA2, which contributed to PB-meditated regulation of EMT. This mechanism is conserved in other cancer types. Furthermore, endoplasmic reticulum stress was an intrinsic signal that induced PB disassembly and translational derepression of HMGA2. Taken together, this study has identified a function of PBs in the regulation of EMT in cancer. SIGNIFICANCE: Systematic investigation of the influence of posttranscriptional regulation on cancer cell motility established a connection between P-body-mediated translational control and EMT, which could be therapeutically exploited to attenuate metastasis formation.


Assuntos
Neoplasias do Colo , Corpos de Processamento , Humanos , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Detecção Precoce de Câncer , Fatores de Transcrição/metabolismo , Transição Epitelial-Mesenquimal/genética , Neoplasias do Colo/patologia , Regulação Neoplásica da Expressão Gênica , Movimento Celular/genética , Linhagem Celular Tumoral , Proteínas/genética
20.
Sci Signal ; 17(817): eadf7318, 2024 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-38166030

RESUMO

The opening of the embryonic leaves (cotyledons) as seedlings emerge from the dark soil into the light is crucial to ensure the survival of the plant. Seedlings that sprout in the dark elongate rapidly to reach light but keep their cotyledons closed. During de-etiolation, the transition from dark to light growth, elongation slows and the cotyledons open. Here, we report that the transcription factor ACTIVATING FACTOR1 (ATAF1) participates in de-etiolation and facilitates light-induced cotyledon opening. The transition from dark to light rapidly induced ATAF1 expression and ATAF1 accumulation in cotyledons. Seedlings lacking or overexpressing ATAF1 exhibited reduced or enhanced cotyledon opening, respectively, and transcriptomic analysis indicated that ATAF1 repressed the expression of genes associated with growth and cotyledon closure. The activation of the photoreceptor phytochrome A (phyA) by far-red light induced its association with the ATAF1 promoter and stimulation of ATAF1 expression. The transcription factor ELONGATED HYPOCOTYL5 (HY5), which is also activated in response far-red light, cooperated with phyA to induce ATAF1 expression. ATAF1 and HY5 interacted with one another and cooperatively repressed the expression of growth-promoting and cotyledon closure genes. Together, our study reveals a mechanism through which far-red light promotes cotyledon opening.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Cotilédone/genética , Cotilédone/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Luz , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Plântula/genética , Plântula/metabolismo , Regulação da Expressão Gênica de Plantas , Fatores de Transcrição de Zíper de Leucina Básica/genética , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Proteínas Repressoras/metabolismo
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