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1.
Nutrients ; 16(9)2024 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-38732567

RESUMO

Imbalances in lipid uptake and efflux and inflammation are major contributors to foam cell formation, which is considered a therapeutic target to protect against atherosclerosis. Naringin, a citrus flavonoid abundant in citrus fruits, has been reported to exert an antiatherogenic function, but its pharmacological mechanism is unclear. Naringin treatment effectively inhibits foam cell formation in THP-1 and RAW264.7 macrophages. In this study, mechanically, naringin maintained lipid homeostasis within macrophages through downregulation of the key genes for lipid uptake (MSR1 and CD36) and the upregulation of ABCA1, ABCG1 and SR-B1, which are responsible for cholesterol efflux. Meanwhile, naringin significantly decreased the cholesterol synthesis-related genes and increased the genes involved in cholesterol metabolism. Subsequently, the results showed that ox-LDL-induced macrophage inflammatory responses were inhibited by naringin by reducing the proinflammatory cytokines IL-1ß, IL-6 and TNF-α, and increasing the anti- inflammatory cytokine IL-10, which was further verified by the downregulation of pro-inflammatory and chemokine-related genes. Additionally, we found that naringin reprogrammed the metabolic phenotypes of macrophages by suppressing glycolysis and promoting lipid oxidation metabolism to restore macrophage phenotypes and functions. These results suggest that naringin is a potential drug for the treatment of AS as it inhibits macrophage foam cell formation by regulating metabolic phenotypes and inflammation.


Assuntos
Flavanonas , Células Espumosas , Homeostase , Metabolismo dos Lipídeos , Fenótipo , Células Espumosas/efeitos dos fármacos , Células Espumosas/metabolismo , Flavanonas/farmacologia , Camundongos , Metabolismo dos Lipídeos/efeitos dos fármacos , Animais , Humanos , Homeostase/efeitos dos fármacos , Células RAW 264.7 , Citocinas/metabolismo , Colesterol/metabolismo , Células THP-1 , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Lipoproteínas LDL/metabolismo , Inflamação/metabolismo , Inflamação/tratamento farmacológico
2.
Clin Exp Med ; 24(1): 99, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38748269

RESUMO

Current clinical guidelines limit surgical intervention to patients with cT1-2N0M0 small cell lung cancer (SCLC). Our objective was to reassess the role of surgery in SCLC management, and explore novel prognostic indicators for surgically resected SCLC. We reviewed all patients diagnosed with SCLC from January 2011 to April 2021 in our institution. Survival analysis was conducted using the Kaplan-Meier method, and independent prognostic factors were assessed through the Cox proportional hazard model. In addition, immunohistochemistry (IHC) staining was performed to evaluate the predictive value of selected indicators in the prognosis of surgically resected SCLC patients. In the study, 177 SCLC patients undergoing surgical resection were ultimately included. Both univariate and multivariate Cox analysis revealed that incomplete postoperative adjuvant therapy emerged as an independent risk factor for adverse prognosis (p < 0.001, HR 2.96). Survival analysis revealed significantly superior survival among pN0-1 patients compared to pN2 patients (p < 0.0001). No significant difference in postoperative survival was observed between pN1 and pN0 patients (p = 0.062). Patients with postoperative stable disease (SD) exhibited lower levels of tumor inflammatory cells (TIC) (p = 0.0047) and IFN-γ expression in both area and intensity (p < 0.0001 and 0.0091, respectively) compared to those with postoperative progressive disease (PD). Conversely, patients with postoperative SD showed elevated levels of stromal inflammatory cells (SIC) (p = 0.0453) and increased counts of CD3+ and CD8+ cells (p = 0.0262 and 0.0330, respectively). Survival analysis indicated that high levels of SIC, along with low levels of IFN-γ+ cell area within tumor tissue, may correlate positively with improved prognosis in surgically resected SCLC (p = 0.017 and 0.012, respectively). In conclusion, the present study revealed that the patients with pT1-2N1M0 staging were a potential subgroup of SCLC patients who may benefit from surgery. Complete postoperative adjuvant therapy remains an independent factor promoting a better prognosis for SCLC patients undergoing surgical resection. Moreover, CD3, CD8, IFN-γ, TIC, and SIC may serve as potential indicators for predicting the prognosis of surgically resected SCLC.


Assuntos
Complexo CD3 , Imuno-Histoquímica , Interferon gama , Neoplasias Pulmonares , Carcinoma de Pequenas Células do Pulmão , Humanos , Masculino , Feminino , Estudos Retrospectivos , Pessoa de Meia-Idade , Prognóstico , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/cirurgia , Neoplasias Pulmonares/mortalidade , Interferon gama/metabolismo , Idoso , Carcinoma de Pequenas Células do Pulmão/cirurgia , Carcinoma de Pequenas Células do Pulmão/patologia , Carcinoma de Pequenas Células do Pulmão/mortalidade , Carcinoma de Pequenas Células do Pulmão/metabolismo , Complexo CD3/metabolismo , Antígenos CD8/metabolismo , Antígenos CD8/análise , Adulto , Biomarcadores Tumorais/análise , Análise de Sobrevida , Idoso de 80 Anos ou mais , Estimativa de Kaplan-Meier , Células Estromais/patologia , Células Estromais/metabolismo
3.
Plant Mol Biol ; 114(3): 52, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38696020

RESUMO

Salt stress is one of the major factors limiting plant growth and productivity. Many studies have shown that serine hydroxymethyltransferase (SHMT) gene play an important role in growth, development and stress response in plants. However, to date, there have been few studies on whether SHMT3 can enhance salt tolerance in plants. Therefore, the effects of overexpression or silencing of CsSHMT3 gene on cucumber seedling growth under salt stress were investigated in this study. The results showed that overexpression of CsSHMT3 gene in cucumber seedlings resulted in a significant increase in chlorophyll content, photosynthetic rate and proline (Pro) content, and antioxidant enzyme activity under salt stress condition; whereas the content of malondialdehyde (MDA), superoxide anion (H2O2), hydrogen peroxide (O2·-) and relative conductivity were significantly decreased when CsSHMT3 gene was overexpressed. However, the content of chlorophyll and Pro, photosynthetic rate, and antioxidant enzyme activity of the silenced CsSHMT3 gene lines under salt stress were significantly reduced, while MDA, H2O2, O2·- content and relative conductivity showed higher level in the silenced CsSHMT3 gene lines. It was further found that the expression of stress-related genes SOD, CAT, SOS1, SOS2, NHX, and HKT was significantly up-regulated by overexpressing CsSHMT3 gene in cucumber seedlings; while stress-related gene expression showed significant decrease in silenced CsSHMT3 gene seedlings under salt stress. This suggests that overexpression of CsSHMT3 gene increased the salt tolerance of cucumber seedlings, while silencing of CsSHMT3 gene decreased the salt tolerance. In conclusion, CsSHMT3 gene might positively regulate salt stress tolerance in cucumber and be involved in regulating antioxidant activity, osmotic adjustment, and photosynthesis under salt stress. KEY MESSAGE: CsSHMT3 gene may positively regulate the expression of osmotic system, photosynthesis, antioxidant system and stress-related genes in cucumber.


Assuntos
Clorofila , Cucumis sativus , Regulação da Expressão Gênica de Plantas , Fotossíntese , Estresse Salino , Tolerância ao Sal , Plântula , Cucumis sativus/genética , Cucumis sativus/crescimento & desenvolvimento , Cucumis sativus/fisiologia , Cucumis sativus/efeitos dos fármacos , Plântula/genética , Plântula/crescimento & desenvolvimento , Plântula/efeitos dos fármacos , Plântula/fisiologia , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Tolerância ao Sal/genética , Estresse Salino/genética , Clorofila/metabolismo , Fotossíntese/genética , Fotossíntese/efeitos dos fármacos , Peróxido de Hidrogênio/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Glicina Hidroximetiltransferase/genética , Glicina Hidroximetiltransferase/metabolismo , Antioxidantes/metabolismo , Malondialdeído/metabolismo , Plantas Geneticamente Modificadas , Inativação Gênica
4.
J Affect Disord ; 356: 737-752, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38649105

RESUMO

The onset of depression commonly occurs in adolescence; therefore, depressive prevention and intervention are pivotal during this period. It is becoming evident that neurotransmitter imbalance and gut microbiota dysbiosis are prominent causes of depression. However, the underlying links and mechanisms remain poorly understood. In this study, with 16S ribosomal RNA gene sequencing, genus Coprococcus markedly differentiated between the healthy and unmedicated depressive adolescents. Based on this, transplantation of Coprococcus eutactus (C.e.) was found to dramatically ameliorate the chronic restraint stress (CRS) induced depression-like changes and prevent synaptic loss and glial-stimulated neuroinflammation in mice. The Ultra-high performance liquid chromatography tandem mass spectrometry analysis (UHPLC-MS/MS) further showed that neurotoxic neurotransmitters in kynurenine pathway (KP) such as 3-hydroxykynurenine (3-HK) and 3-hydroxyanthranilic acid (3-HAA) decreased in mouse brains, mechanistically deciphering the transfer of the tryptophan metabolic pathway to serotonin metabolic signaling in the brain after C.e. treatment, which was also verified in the colon. Molecularly, blockage of KP activities mediated by C.e. was ascribed to the restraint of the limit-step enzymes responsible for kynurenine, 3-HK, and quinolinic acid generation. In the colon, C.e. treatment significantly recovered goblet cells and mucus secretion in CRS mice which may ascribe to the rebalance of the disordered gut microbiota, especially Akkermansia, Roseburia, Rikenella, Blautia, and Alloprevotella. Taken together, the current study reveals for the first time the beneficial effects and potential mechanisms of C.e. in ameliorating CRS-induced depression, unraveling the direct links between C.e. treatment and neurotransmitter rebalance, which may provide efficacious therapeutic avenues for adolescent depressive intervention.


Assuntos
Depressão , Microbioma Gastrointestinal , Neurotransmissores , Restrição Física , Estresse Psicológico , Animais , Camundongos , Microbioma Gastrointestinal/fisiologia , Estresse Psicológico/metabolismo , Estresse Psicológico/complicações , Depressão/metabolismo , Humanos , Masculino , Neurotransmissores/metabolismo , Modelos Animais de Doenças , Adolescente , Encéfalo/metabolismo , Cinurenina/metabolismo , Cinurenina/análogos & derivados
5.
Cell Mol Biol Lett ; 29(1): 57, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38649857

RESUMO

In tomato (Solanum lycopersicum), the ripening of fruit is regulated by the selective expression of ripening-related genes, and this procedure is controlled by transcription factors (TFs). In the various plant-specific TF families, the no apical meristem (NAM), Arabidopsis thaliana activating factor 1/2 (ATAF1/2), and cup-shaped cotyledon 2 (CUC2; NAC) TF family stands out and plays a significant function in plant physiological activities, such as fruit ripening (FR). Despite the numerous genes of NAC found in the tomato genome, limited information is available on the effects of NAC members on FR, and there is also a lack of studies on their target genes. In this research, we focus on SlNAP1, which is a NAC TF that positively influences the FR of tomato. By employing CRISPR/Cas9 technology, compared with the wild type (WT), we generated slnap1 mutants and observed a delay in the ethylene production and color change of fruits. We employed the yeast one-hybrid (Y1H) and dual-luciferase reporter (DLR) assays to confirm that SlNAP1 directly binds to the promoters of two crucial genes involved in gibberellin (GA) degradation, namely SlGA2ox1 and SlGA2ox5, thus activating their expression. Furthermore, through a yeast two-hybrid (Y2H), bimolecular fluorescence complementation (BIFC) and luciferase (LUC) assays, we established an interaction between SlNAP1 and SlGID1. Hence, our findings suggest that SlNAP1 regulates FR positively by activating the GA degradation genes directly. Additionally, the interaction between SlNAP1 and SlGID1 may play a role in SlNAP1-induced FR. Overall, our study provides important insights into the molecular mechanisms through which NAC TFs regulate tomato FR via the GA pathway.


Assuntos
Frutas , Regulação da Expressão Gênica de Plantas , Giberelinas , Proteínas de Plantas , Solanum lycopersicum , Fatores de Transcrição , Solanum lycopersicum/genética , Solanum lycopersicum/crescimento & desenvolvimento , Solanum lycopersicum/metabolismo , Frutas/genética , Frutas/crescimento & desenvolvimento , Frutas/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Giberelinas/metabolismo , Regiões Promotoras Genéticas/genética , Etilenos/metabolismo
6.
Mater Horiz ; 11(10): 2457-2468, 2024 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-38465967

RESUMO

In vivo transmembrane-voltage detection reflected the electrophysiological activities of the biological system, which is crucial for the diagnosis of neuronal disease. Traditional implanted electrodes can only monitor limited regions and induce relatively large tissue damage. Despite emerging monitoring methods based on optical imaging have access to signal recording in a larger area, the recording wavelength of less than 1000 nm seriously weakens the detection depth and resolution in vivo. Herein, a Förster resonance energy transfer (FRET)-based nano-indicator, NaYbF4:Er@NaYF4@Cy7.5@DPPC (Cy7.5-ErNP) with emission in the near-infrared IIb biological window (NIR-IIb, 1500-1700 nm) is developed for transmembrane-voltage detection. Cy7.5 dye is found to be voltage-sensitive and is employed as the energy donor for the energy transfer to the lanthanide nanoparticle, NaYbF4:Er@NaYF4 (ErNP), which works as the acceptor to achieve electrophysiological signal responsive NIR-IIb luminescence. Benefiting from the high penetration and low scattering of NIR-IIb luminescence, the Cy7.5-ErNP enables both the visualization of action potential in vitro and monitoring of Mesial Temporal lobe epilepsy (mTLE) disease in vivo. This work presents a concept for leveraging the lanthanide luminescent nanoprobes to visualize electrophysiological activity in vivo, which facilitates the development of an optical nano-indicator for the diagnosis of neurological disorders.


Assuntos
Transferência Ressonante de Energia de Fluorescência , Nanopartículas , Animais , Transferência Ressonante de Energia de Fluorescência/métodos , Imagem Óptica/métodos , Camundongos , Fenômenos Eletrofisiológicos/fisiologia , Raios Infravermelhos , Humanos , Masculino , Ratos , Potenciais de Ação/fisiologia , Corantes Fluorescentes
7.
Angew Chem Int Ed Engl ; 63(22): e202404258, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38454791

RESUMO

Engineering advantageous defects to construct well-defined active sites in catalysts is promising but challenging to achieve efficient photocatalytic NH3 synthesis from N2 and H2O due to the chemical inertness of N2 molecule. Here, we report defective Fe-based metal-organic framework (MOF) photocatalysts via a non-thermal plasma-assisted synthesis strategy, where their NH3 production capability is synergistically regulated by two types of defects, namely, bridging organic ligands and terminal inorganic ligands (OH- and H2O). Specially, the optimized MIL-100(Fe) catalysts, where there are only terminal inorganic ligand defects and coexistence of dual defects, exhibit the respective 1.7- and 7.7-fold activity enhancement comparable to the pristine catalyst under visible light irradiation. As revealed by experimental and theoretical calculation results, the dual defects in the catalyst induce the formation of abundant and highly accessible coordinatively unsaturated Fe active sites and synergistically optimize their geometric and electronic structures, which favors the injection of more d-orbital electrons in Fe sites into the N2 π* antibonding orbital to achieve N2 activation and the formation of a key intermediate *NNH in the reaction. This work provides a guidance on the rational design and accurate construction of porous catalysts with precise defective structures for high-performance activation of catalytic molecules.

8.
Neuroscience ; 545: 111-124, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38492796

RESUMO

Armcx1 is a member of the ARMadillo repeat-Containing protein on the X chromosome (ARMCX) family, which is recognized to have evolutionary conserved roles in regulating mitochondrial transport and dynamics. Previous research has shown that Armcx1 is expressed at higher levels in mice after axotomy and in adult retinal ganglion cells after crush injury, and this protein increases neuronal survival and axonal regeneration. However, its role in traumatic brain injury (TBI) is unclear. Therefore, the aim of this study was to assess the expression of Armcx1 after TBI and to explore possible related mechanisms by which Armcx1 is involved in TBI. We used C57BL/6 male mice to model TBI and evaluated the role of Armcx1 in TBI by transfecting mice with Armcx1 small interfering RNA (siRNA) to inhibit Armcx1 expression 24 h before TBI modeling. Western blotting, immunofluorescence, terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) staining, Nissl staining, transmission electron microscopy, adenosine triphosphate (ATP) level measurement, neuronal apoptosis analysis, neurological function scoring and the Morris water maze were performed. The results demonstrated that Armcx1 protein expression was elevated after TBI and that the Armcx1 protein was localized in neurons and astroglial cells in cortical tissue surrounding the injury site. In addition, inhibition of Armcx1 expression further led to impaired mitochondrial transport, abnormal morphology, reduced ATP levels, aggravation of neuronal apoptosis and neurological dysfunction, and decrease Miro1 expression. In conclusion, our findings indicate that Armcx1 may exert neuroprotective effects by ameliorating neurological injury after TBI through a mitochondrial transport pathway involving Miro1.


Assuntos
Proteínas do Domínio Armadillo , Lesões Encefálicas Traumáticas , Camundongos Endogâmicos C57BL , Mitocôndrias , Proteínas rho de Ligação ao GTP , Animais , Masculino , Camundongos , Trifosfato de Adenosina/metabolismo , Apoptose/fisiologia , Proteínas do Domínio Armadillo/metabolismo , Lesões Encefálicas Traumáticas/metabolismo , Lesões Encefálicas Traumáticas/patologia , Modelos Animais de Doenças , Aprendizagem em Labirinto/fisiologia , Mitocôndrias/metabolismo , Neurônios/metabolismo , Neurônios/patologia , Proteínas rho de Ligação ao GTP/metabolismo
9.
Gut Microbes ; 16(1): 2327349, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38512768

RESUMO

In the development of Type 1 diabetes (T1D), there are critical states just before drastic changes, and identifying these pre-disease states may predict T1D or provide crucial early-warning signals. Unlike gene expression data, gut microbiome data can be collected noninvasively from stool samples. Gut microbiome sequencing data contain different levels of phylogenetic information that can be utilized to detect the tipping point or critical state in a reliable manner, thereby providing accurate and effective early-warning signals. However, it is still difficult to detect the critical state of T1D based on gut microbiome data due to generally non-significant differences between healthy and critical states. To address this problem, we proposed a new method - microbiome network flow entropy (mNFE) based on a single sample from each individual - for detecting the critical state before seroconversion and abrupt transitions of T1D at various taxonomic levels. The numerical simulation validated the robustness of mNFE under different noise levels. Furthermore, based on real datasets, mNFE successfully identified the critical states and their dynamic network biomarkers (DNBs) at different taxonomic levels. In addition, we found some high-frequency species, which are closely related to the unique clinical characteristics of autoantibodies at the four levels, and identified some non-differential 'dark species' play important roles during the T1D progression. mNFE can robustly and effectively detect the pre-disease states at various taxonomic levels and identify the corresponding DNBs with only a single sample for each individual. Therefore, our mNFE method provides a new approach not only for T1D pre-disease diagnosis or preventative treatment but also for preventative medicine of other diseases by gut microbiome.


Assuntos
Diabetes Mellitus Tipo 1 , Dinitrofluorbenzeno/análogos & derivados , Microbioma Gastrointestinal , Humanos , Diabetes Mellitus Tipo 1/diagnóstico , Entropia , Filogenia , Biomarcadores
10.
J Phys Chem Lett ; 15(12): 3470-3477, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38512331

RESUMO

The photosystem of filamentous anoxygenic phototroph Roseiflexus (Rfl.) castenholzii comprises a light-harvesting (LH) complex encircling a reaction center (RC), which intensely absorbs blue-green light by carotenoid (Car) and near-infrared light by bacteriochlorophyll (BChl). To explore the influence of light quality (color) on the photosynthetic activity, we compared the pigment compositions and triplet excitation dynamics of the LH-RCs from Rfl. castenholzii was adapted to blue-green light (bg-LH-RC) and to near-infrared light (nir-LH-RC). Both LH-RCs bind γ-carotene derivatives; however, compared to that of nir-LH-RC (12%), bg-LH-RC contains substantially higher keto-γ-carotene content (43%) and shows considerably faster BChl-to-Car triplet excitation transfer (10.9 ns vs 15.0 ns). For bg-LH-RC, but not nir-LH-RC, selective photoexcitation of Car and the 800 nm-absorbing BChl led to Car-to-Car triplet transfer and BChl-Car singlet fission reactions, respectively. The unique excitation dynamics of bg-LH-RC enhances its photoprotection, which is crucial for the survival of aquatic anoxygenic phototrophs from photooxidative stress.


Assuntos
Chloroflexi , Chloroflexi/química , Chloroflexi/metabolismo , Carotenoides , Complexos de Proteínas Captadores de Luz/química , Fotossíntese , Bacterioclorofilas/metabolismo , Proteínas de Bactérias/química
11.
Immunotherapy ; 16(7): 465-480, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38511241

RESUMO

Aim: This study aims to clarify the efficacy and adverse effects of immune checkpoint inhibitors (ICIs) in the lung cancer patients with a history of interstitial lung disease (ILD). Methods: From the inception of the database to 4 April 2023, we systematically searched the four databases. Results: The objective remission rate, disease control rate, incidence of immune-associated pneumonitis (ICIP) in the combined ILD group were significantly higher than those in the non-combined ILD group. There were no significant differences between the two groups in progression-free survival, overall survival, renal insufficiency, thyroid dysfunction and gastrointestinal toxicity. Conclusion: Generally, a pre-existing ILD history can increase the efficacy and incidence of ICIs' adverse reactions. Therefore, ICIs should be administered with caution.


Immune checkpoint inhibitors are a type of immunotherapy used to treat lung cancer. Some experts disagree over whether it is safe and effective to use this type of immunotherapy in people with lung cancer who also have lung disease. In this paper, the researchers analyzed the results of lots of different studies relating to the use of immune checkpoint inhibitors to treat lung cancer in patients with and without lung disease. They wanted to find out whether immune checkpoint inhibitors differed in their effectiveness between the two groups of patients. They also looked at whether patients with lung disease experienced more negative side effects from the immunotherapy treatment. The researchers found that patients with lung disease had a bigger response to immune checkpoint inhibitor treatment than patients without lung disease. This means that this type of immunotherapy is likely to be effective at treating lung cancer in patients with lung disease. However, the researchers also found that this patient group was more likely to experience negative side effects from the immunotherapy treatment. In particular, there were many more cases of pneumonia in this group than in the patients without lung disease. Therefore, doctors should be cautious when using immunotherapy to treat lung cancer patients with lung disease, ensuring they take measures to prevent pneumonia and be better prepared in case negative side effects occur.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Doenças Pulmonares Intersticiais , Neoplasias Pulmonares , Pneumonia , Humanos , Inibidores de Checkpoint Imunológico/efeitos adversos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Doenças Pulmonares Intersticiais/tratamento farmacológico , Doenças Pulmonares Intersticiais/etiologia , Estudos Retrospectivos
12.
Polymers (Basel) ; 16(6)2024 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-38543368

RESUMO

Since the discovery of α-diimine catalysts in 1995, an extensive series of Brookhart-type complexes have shown their excellence in catalyzing ethylene polymerizations with remarkable activity and a high molecular weight. However, although this class of palladium complexes has proven proficiency in catalyzing ethylene copolymerization with various polar monomers, the α-diimine nickel catalysts have generally exhibited a much worse performance in these copolymerizations compared to their palladium counterparts. Recently, Brookhart et al. reported a notable exception, demonstrating that α-diimine nickel catalysts could catalyze the ethylene copolymerization with some vinylalkoxysilanes effectively, producing functionalized polyethylene incorporating trialkoxysilane (-Si(OR)3) groups. This breakthrough is significant since Pd-catalyzed copolymerizations are commercially less usable due to the high cost of palladium. Thus, the utilization of Ni, given its abundance in raw materials and cost-effectiveness, is a landmark in ethylene/polar vinyl monomer copolymerization. Inspired by these findings, we used density functional theory (DFT) calculations to investigate the mechanistic study of ethylene copolymerization with vinyltrimethoxysilane (VTMoS) catalyzed by Brookhart-type nickel catalysts, aiming to elucidate the molecular-level understanding of this unique reaction. Initially, the nickel complexes and cationic active species were optimized through DFT calculations. Subsequently, we explored the mechanisms including the chain initiation, chain propagation, and chain termination of ethylene homopolymerization and copolymerization catalyzed by Brookhart-type complexes. Finally, we conducted an energetic analysis of both the in-chain and chain-end of silane enchainment. It was found that chain initiation is the dominant step in the ethylene homopolymerization catalyzed by the α-diimine Ni complex. The 1,2- and 2,1-insertion of vinylalkoxysilane exhibit similar barriers, explaining the fact that both five-membered and four-membered chelates were identified experimentally. After the VTMoS insertion, the barriers of ethylene reinsertion become higher, indicating that this step is the rate-determining step, which could be attributed to the steric hindrance between the incoming ethylene and the bulky silane substrate. We have also reported the energetic analysis of the distribution of polar substrates. The dominant pathway of chain-end -Si(OR)3 incorporation is suggested as chain-walking → ring-opening → ethylene insertion, and the preference of chain-end -Si(OR)3 incorporation is primarily attributed to the steric repulsion between the pre-inserted silane group and the incoming ethylene molecule, reducing the likelihood of in-chain incorporation.

13.
J Hypertens ; 42(6): 1048-1056, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38406922

RESUMO

BACKGROUND: The correlation between systolic blood pressure (SBP) and mortality in hypertensive patients with different phenotypes of heart failure (HF) has not been adequately studied, and optimal blood pressure control targets remain controversial. To explore the link between SBP and prognosis in all or three ejection fraction (EF) phenotypes of HF patients with hypertension. METHODS: We analyzed 1279 HF patients complicated by hypertension in a retrospective cohort. The SBP <130 mmHg group included 383 patients, and the SBP ≥130 mmHg group included 896 patients. The major end point was all-cause mortality. RESULTS: Of the 1279 study patients, with a median age of 66.0 ±â€Š12.0 years, 45.3% were female. The proportions of the three subtypes of heart failure complicated with hypertension (HFrEF, HEmrEF, and HFpEF) were 26.8%, 29.3%, and 43.9%, respectively. During the 1-year follow-up, 223 patients experienced all-cause death, and 133 experienced cardiovascular death. Restricted cubic splines showed that the risk of all-cause and cardiovascular death increased gradually as the SBP level decreased in patients with HFrEF and HFmrEF. Furthermore, the multivariate Cox proportional hazards model revealed that SBP <130 mmHg was also associated with an increased risk of all-cause death [hazard ratio (HR) 2.53, 95% confidence interval (CI) 1.23-5.20, P  = 0.011] and cardiovascular death (HR 1.91, 95% CI 1.01-3.63, P  = 0.047) in HFrEF patients. A trend toward increased risk was observed among HFmrEF patients, but it was not statistically significant. This trend was not observed in HFpEF patients. CONCLUSION: In HFrEF patients, SBP <130 mmHg was associated with an increased risk of all-cause and cardiovascular mortality. A trend toward increased risk was observed among HFmrEF patients, but not among HFpEF patients.


Assuntos
Pressão Sanguínea , Insuficiência Cardíaca , Hipertensão , Humanos , Feminino , Insuficiência Cardíaca/mortalidade , Insuficiência Cardíaca/fisiopatologia , Insuficiência Cardíaca/complicações , Masculino , Idoso , Hipertensão/fisiopatologia , Hipertensão/mortalidade , Hipertensão/complicações , Estudos Retrospectivos , Pessoa de Meia-Idade , Volume Sistólico/fisiologia , Prognóstico , Sístole
14.
Angew Chem Int Ed Engl ; 63(14): e202319216, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38337143

RESUMO

The synthesis of hydrogen peroxide through artificial photosynthesis is a green and promising technology with advantages in sustainability, economy and safety. However, superoxide radical (⋅O2 -), an important intermediate in photocatalytic oxygen reduction to H2O2 production, has strong oxidizing properties that potentially destabilize the catalyst. Therefore, avoiding the accumulation of ⋅O2 - for its rapid conversion to H2O2 is of paramount significance in improving catalyst stability and H2O2 yield. In this work, a strategy was developed to utilize protonated groups for the rapid depletion of converted ⋅O2 -, thereby the efficiency of photocatalytic synthesis of H2O2 from CN was successfully enhanced by 47-fold. The experimental findings demonstrated that polydopamine not only improved carrier separation efficiency, and more importantly, provided the adsorption reduction active site for ⋅O2 - for efficient H2O2 production. This work offers a versatile approach for synthesizing efficient and stable photocatalysts.

15.
Insects ; 15(1)2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38249056

RESUMO

Monolepta is one of the diverse genera in the subfamily Galerucinae, including 708 species and 6 sub-species worldwide. To explore the information on the mitogenome characteristics and phylogeny of the section "Monoleptites", especially the genus Monolepta, we obtained the newly completed mitochondrial genomes (mitogenomes) of four Monolepta species using high-throughput sequencing technology. The lengths of these four new mitochondrial genomes are 16,672 bp, 16,965 bp, 16,012 bp, and 15,866 bp in size, respectively. All four mitochondrial genomes include 22 transfer RNA genes (tRNAs), 13 protein-coding genes (PCGs), 2 ribosomal RNA genes (rRNAs), and one control region, which is consistent with other Coleoptera. The results of the nonsynonymous with synonymous substitution rates showed that ND6 had the highest evolution rate, while COI displayed the lowest evolution rate. The substitution saturation of three datasets (13 PCGs_codon1, 13 PCGs_codon2, 13 PCGs_codon3) showed that there was no saturation across all datasets. Phylogenetic analyses based on three datasets (ND1, 15 genes of mitogenomes, and 13 PCGs_AA) were carried out using maximum likelihood (ML) and Bayesian inference (BI) methods. The results showed that mitogenomes had a greater capacity to resolve the main clades than the ND1 gene at the suprageneric and species levels. The section "Monoleptites" was proven to be a monophyletic group, while Monolepta was a non-monophyletic group. Based on ND1 data, the newly sequenced species whose antennal segment 2 was shorter than 3 were split into several clades, while, based on the mitogenomic dataset, the four newly sequenced species had close relationships with Paleosepharia. The species whose antennal segment 2 was as long as 3 were split into two clades, which indicated that the characteristic of "antennal segment 2 as long as 3" of the true "Monolepta" evolved multiple times in several subgroups. Therefore, to explore the relationships among the true Monolepta, the most important thing is to perform a thorough revision of Monolepta and related genera in the future.

16.
Respir Res ; 25(1): 6, 2024 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-38178133

RESUMO

BACKGROUND: Airway remodeling is a poorly reversible feature of asthma which lacks effective therapeutic interventions. CD147 can regulate extracellular matrix (ECM) remodeling and tissue fibrosis, and participate in the pathogenesis of asthma. In this study, the role of CD147 in airway remodeling and activation of circulating fibrocytes was investigated in asthmatic mice. METHODS: Asthmatic mouse model was established by sensitizing and challenging mice with ovalbumin (OVA), and treated with anti-CD147 or Isotype antibody. The number of eosinophils in bronchoalveolar lavage fluid (BALF) was examined by microscope, and the levels of interleukin-4 (IL-4), IL-5 and IL-13 in BALF were detected by enzyme-linked immunosorbent assay (ELISA). The number of CD45+ and collagen I (COL-I)+ circulating fibrocytes in BALF was detected by flow cytometry. Lung tissue sections were respectively stained with hematoxylin and eosin (HE), periodic acid-Schiff (PAS) or Masson trichrome staining, or used for immunohistochemistry of CD31 and immunohistofluorescence of α-smooth muscle actin (α-SMA), CD45 and COL-I. The protein expression of α-SMA, vascular endothelial growth factor (VEGF), transforming growth factor-ß1 (TGF-ß1), Fibronectin, and COL-I was determined by western blotting. RESULTS: Anti-CD147 treatment significantly reduced the number of eosinophils and the levels of IL-4, IL-13, and IL-5 in BALF, and repressed airway inflammatory infiltration and airway wall thickening in asthmatic mice. Anti-CD147 treatment also reduced airway goblet cell metaplasia, collagen deposition, and angiogenesis in asthmatic mice, accompanied by inhibition of VEGF and α-SMA expression. The number of CD45+COL-I+ circulating fibrocytes was increased in BALF and lung tissues of OVA-induced asthmatic mice, but was decreased by anti-CD147 treatment. In addition, anti-CD147 treatment also reduced the protein expression of COL-I, fibronectin, and TGF-ß1 in lung tissues of asthmatic mice. CONCLUSION: OVA-triggered airway inflammation and airway remodeling in asthmatic mice can be repressed by anti-CD147 treatment, along with inhibiting the accumulation and activation of circulating fibrocytes.


Assuntos
Asma , Basigina , Animais , Camundongos , Remodelação das Vias Aéreas , Asma/tratamento farmacológico , Colágeno Tipo I , Fibronectinas , Interleucina-13 , Interleucina-4 , Interleucina-5 , Fator de Crescimento Transformador beta1 , Fator A de Crescimento do Endotélio Vascular
17.
Brain Res Bull ; 207: 110870, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38185389

RESUMO

Traumatic brain injury (TBI) is a common disease worldwide with high mortality and disability rates. Besides the primary mechanical injury, the secondary injury associated with TBI can also induce numerous pathological changes, such as brain edema, nerve apoptosis, and neuroinflammation, which further aggravates neurological dysfunction and even causes the death due to the primary injury. Among them, neuronal apoptosis is a key link in the injury. Melanocortin-1 receptor (MC1R) is a G protein coupled receptor, belonging to the melanocortin receptor family. Studies have shown that activation of MC1R inhibits oxidative stress and apoptosis, and confers neuroprotective effects against various neurological diseases. Merlin is a protein product of the NF2 gene, which is widely expressed in the central nervous system (CNS) of mice, rats, and humans. Studies have indicated that Merlin is associated with MC1R. In this study, we explored the anti-apoptotic effects and potential mechanisms of MC1R. A rat model of TBI was established through controlled cortical impact. The MC1R-specific agonist Nle4-D-Phe7-α-Melanocyte (NDP-MSH) and the inhibitor MSG-606 were employed to explore the effects of MC1R and Merlin following TBI and investigated the associated mechanisms. The results showed that the expression levels of MC1R and Merlin were upregulated after TBI, and activation of MC1R promoted Merlin expression. Further, we found that MC1R activation significantly improved neurological dysfunction and reduced brain edema and neuronal apoptosis induced by TBI in rats. Mechanistically, its neuroprotective function and anti-apoptotic were partly associated with MC1R activation. In conclusion, we demonstrated that MC1R activation after TBI may inhibit apoptosis and confer neuroprotection by upregulating the expression of Merlin.


Assuntos
Edema Encefálico , Lesões Encefálicas Traumáticas , Animais , Ratos , Apoptose , Edema Encefálico/etiologia , Lesões Encefálicas Traumáticas/patologia , Genes da Neurofibromatose 2 , Neurofibromina 2/genética , Neurofibromina 2/farmacologia , Receptor Tipo 1 de Melanocortina/genética , Receptor Tipo 1 de Melanocortina/metabolismo
18.
Environ Pollut ; 346: 123356, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38266696

RESUMO

Bisphenol F (BPF), one of the major alternatives of Bisphenol A (BPA), is becoming extensively used in industrial production with great harm to human beings and environment. Recent studies have revealed that environmental exposure is crucial to the initiation and development of depression. Thereby, the aim the present study is to ascertain the correlationship between the BPF exposure and depression occurrence. In the current study, BPF strikingly triggered depression-like changes in mice through the sucrose preference test (SPT), tail suspension test (TST) and forced swim test (FST), accompanied by the perturbation of the kynurenine (KYN) metabolic pathway along the "liver-brain" axis. Mechanistically, the neurotransmitters from the tryptophan metabolic pathway were converted to the toxic KYN pathway after BPF treatment. With the ELISA assay, it revealed that the toxic KYN metabolites, including KYN and 3-hydroxykynurenine (3-HK), were strikingly increased in the mouse brains which was ascribed to the enhanced expression of the rate-limiting enzymes Indoleamine 2,3-dioxygenase (IDO1) and Kynurenine 3-monooxygenase (KMO) respectively. Interestingly, the increased brain KYN induced by BPF was also validated partially from the periphery, since the ELISA and western blotting results indicated the significantly increased KYN in the serum and L-type amino acid transporter 1 (LAT1) in the brain, the key transporter responsible for KYN and 3-HK crossing the blood-brain barrier. Intriguingly, the liver-derived KYN metabolic pathway was the important source of the peripheral KYN and 3-HK, as BPF substantially enhanced hepatic IDO1, Tryptophan, 2, 3-dioxygenase (TDO2), and KMO levels indicated by western blotting. This study is the first to delineate previously unrecognized BPF-induced depression by regulating the KYN metabolic pathway along the "liver-brain" axis; therefore, targeting LAT1 or hepatic KYN signaling may provide a potentially unique therapeutic intervention in BPF-induced depression.


Assuntos
Compostos Benzidrílicos , Cinurenina , Fenóis , Triptofano , Humanos , Camundongos , Animais , Cinurenina/metabolismo , Triptofano/metabolismo , Depressão/induzido quimicamente , Encéfalo/metabolismo , Fígado/metabolismo , Redes e Vias Metabólicas
19.
Mol Med ; 30(1): 4, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38172666

RESUMO

BACKGROUND: Autophagic defects are involved in Methamphetamine (Meth)-induced neurotoxicity. Syntaxin 17 (Stx17), a member of the SNARE protein family, participating in several stages of autophagy, including autophagosome-late endosome/lysosome fusion. However, the role of Stx17 and potential mechanisms in autophagic defects induced by Meth remain poorly understood. METHODS: To address the mechanism of Meth-induced cognitive impairment, the adenovirus (AV) and adeno-associated virus (AAV) were injected into the hippocampus for stereotaxis to overexpress Stx17 in vivo to examine the cognitive ability via morris water maze and novel object recognition. In molecular level, the synaptic injury and autophagic defects were evaluated. To address the Meth induced neuronal damage, the epidermal growth factor receptor (EGFR) degradation assay was performed to evaluate the degradability of the "cargos" mediated by Meth, and mechanistically, the maturation of the vesicles, including autophagosomes and endosomes, were validated by the Co-IP and the GTP-agarose affinity isolation assays. RESULTS: Overexpression of Stx17 in the hippocampus markedly rescued the Meth-induced cognitive impairment and synaptic loss. For endosomes, Meth exposure upregulated Rab5 expression and its guanine-nucleotide exchange factor (GEF) (immature endosome), with a commensurate decreased active form of Rab7 (Rab7-GTP) and impeded the binding of Rab7 to CCZ1 (mature endosome); for autophagosomes, Meth treatment elicited a dramatic reduction in the overlap between Stx17 and autophagosomes but increased the colocalization of ATG5 and autophagosomes (immature autophagosomes). After Stx17 overexpression, the Rab7-GTP levels in purified late endosomes were substantially increased in parallel with the elevated mature autophagosomes, facilitating cargo (Aß42, p-tau, and EGFR) degradation in the vesicles, which finally ameliorated Meth-induced synaptic loss and memory deficits in mice. CONCLUSION: Stx17 decrease mediated by Meth contributes to vesicle fusion defects which may ascribe to the immature autophagosomes and endosomes, leading to autophagic dysfunction and finalizes neuronal damage and cognitive impairments. Therefore, targeting Stx17 may be a novel therapeutic strategy for Meth-induced neuronal injury.


Assuntos
Autofagossomos , Autofagia , Animais , Camundongos , Autofagossomos/metabolismo , Endossomos/metabolismo , Receptores ErbB/metabolismo , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Guanosina Trifosfato/metabolismo
20.
J Asian Nat Prod Res ; 26(2): 204-213, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38213077

RESUMO

Three new cadinane sesquiterpenes (1-3) and three known sesquiterpenes were isolated from the stems and branches of Illicium ternstroemioides A. C. Smith. The structures of the new compounds were elucidated by extensive analysis of spectroscopic and HRESIMS data. The structures of illiternins A-C (1-3) were confirmed by single crystal X-ray diffraction, allowing for the determination of their absolute configurations. Compounds 3 and 6 exhibited antiviral activity against Coxsackievirus B3 with IC50 values of 33.3 and 57.7 µM, respectively.


Assuntos
Illicium , Sesquiterpenos , Illicium/química , Estrutura Molecular , Sesquiterpenos Policíclicos , Sesquiterpenos/química
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