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1.
Int J Mol Sci ; 25(18)2024 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-39337650

RESUMO

Anxiety disorder is a universal disease related to neuro-inflammation. Solanesol has shown positive effects because of its anti-inflammatory, anti-tumor, and anti-ulcer properties. This study focused on determining whether solanesol could ameliorate anxiety-like behaviors in a mouse model of neuro-inflammation and identify its working targets. Complete Freund's adjuvant (CFA)-induced mice that were intra-peritoneally administered with solanesol (50 mg/kg) for 1 week showed a statistically significant reduction in anxiety-like behaviors, as measured by open field and elevated plus-maze tests. Western blot analysis revealed that CFA-induced upregulation of the levels of pro-inflammatory cytokines interleukin (IL)-1ß and tumor necrosis factor α (TNF-α), which played crucial roles in regulating anxiety, returned to normal in the anterior cingulate cortex (ACC) after solanesol treatment. The level of T cell-restricted intracellular antigen-1 (TIA1), a key component of stress granules, also decreased in the ACC. Moreover, immunofluorescence results indicated that solanesol suppressed CFA-induced microglial and astrocytic activation in the ACC. CFA was injected in the hind paws of TIA1Nestin conditional knockout (cKO) mice to confirm whether TIA1 is a potential modulatory molecule that influences pro-inflammatory cytokines and anxiety-like behaviors. Anxiety-like behaviors could not be observed in cKO mice after CFA injection with IL-1ß and TNF-α levels not remarkedly increasing. Our findings suggest that solanesol inhibits neuro-inflammation by decreasing the TIA1 level to reduce IL-1ß and TNF-α expression, meanwhile inhibiting microglial and astrocytic activation in the ACC and ultimately ameliorating anxiety-like behaviors in mice.


Assuntos
Ansiedade , Modelos Animais de Doenças , Adjuvante de Freund , Giro do Cíngulo , Animais , Camundongos , Ansiedade/tratamento farmacológico , Masculino , Giro do Cíngulo/efeitos dos fármacos , Giro do Cíngulo/metabolismo , Interleucina-1beta/metabolismo , Camundongos Endogâmicos C57BL , Comportamento Animal/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Fator de Necrose Tumoral alfa/metabolismo , Microglia/efeitos dos fármacos , Microglia/metabolismo
2.
Front Physiol ; 15: 1437042, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39234311

RESUMO

This study investigated the impact of sweeteners on the release of heavy metals during the heating and atomization processes in electronic cigarettes. Based on a PG/VG base e-liquid with the addition of 2% and 5% neotame or sucralose, we quantitatively analyzed the impact of sweetener content on the levels of heavy metals such as Ni, Cr, and Fe in the e-liquid and aerosol after heating and atomization. Additionally, the heated e-liquid samples were used to culture SH-SY-5Y and Beas-2B cells, and their cytotoxic effects were assessed using the CCK-8 assay. The results indicated that the e-liquid with 5% sucralose had the highest average levels of heavy metals after heating and atomization, particularly nickel (13.36 ± 2.50 mg/kg in the e-liquid and 12,109 ± 3,229 ng/200 puffs in the aerosol), whereas the e-liquid with neotame had significantly lower average heavy metal content in comparison. Additionally, it was measured that the chloride ion concentration in the e-liquid with 5% sucralose reached 191 mg/kg after heating at 200°C for 1 h, indicating that heating sucralose generated chloride ions, Which might corrode metal parts components leading to heavy metal release. Cytotoxicity tests revealed that the base e-liquid without sweeteners exhibited the highest average cell viability after heating, at 64.80% ± 2.84% in SH-SY-5Y cells and 63.24% ± 0.86% in Beas-2B cells. Conversely, the e-liquid variant with 5% sucralose showed a significant reduction in average cell viability, reducing it to 50.74% ± 0.88% in SH-SY-5Y cells and 53.03% ± 0.76% in Beas-2B cells, highlighting its more pronounced cytotoxic effects compared to other tested e-liquids. In conclusion, sucralose in e-liquids should be limited preferably less than 2%, or replaced with neotame, a safer alternative, to minimize health risks.

3.
J Phys Chem A ; 128(38): 8111-8122, 2024 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-39283291

RESUMO

The first high-resolution translational spectroscopy studies of D atom photoproducts following excitation to the Rydberg states of D2S are reported. Excitation at wavelengths λ ∼ 139.1 nm reveals an unusual 'inverse' isotope effect; the 1B1(3da1←2b1) Rydberg state of D2S predissociates much faster than its counterpart in H2S. This is attributed to accidental near resonance with a vibrationally excited level of a lower-lying, more heavily predissociated Rydberg state of D2S that boosts the probability of nonadiabatic coupling to the dissociation continuum with 1A″ symmetry. Excitation at λ ∼ 129.1 nm populates the 1B1(4da1←2b1) Rydberg state, which predissociates more slowly and allows the study of ways in which the branching into different quantum states of the SD products varies with the choice of parent excited (JKaKc) level. All excited parent levels yield both ground (X) and electronically excited (A) state SD fragments. The former are distributed over a wide range of rovibrational (v″, N″) levels, while the population of levels with low v' and high N' is favored in the latter. These trends reflect the topographies of the dissociative 1A″ (1A') potential energy surfaces that correlate with the respective dissociation limits. Rotational motion about the b-inertial axis in the excited state molecule increases the relative yield of SD(A) products, consistent with dissociation by rotationally (Coriolis-) induced coupling from the photoexcited Rydberg level to the 1A' continuum. Molecules excited to the rotationless (JKaKc = 000) level also yield some SD(A) products, however, confirming the operation of a rival fragmentation pathway wherein photoexcited molecules decay by initial vibronic coupling to the 1A″ continuum, with subsequent nonadiabatic coupling between the 1A″ and 1A' continua enabling access to the D + SD(A) limit.

4.
Org Biomol Chem ; 22(42): 8397-8400, 2024 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-39329403

RESUMO

Here we report a three-component reaction of 2-formylarylboronic acids, N-sulfonyl amines and 1,3-enynes, proceeding through a cascade imine formation/Pd0-catalysed vinylogous addition/intramolecular Suzuki coupling/isomerization process. This protocol exhibited broad substrate scope and good functionality tolerance, and a spectrum of multifunctionalised benzofulvene derivatives were furnished in moderate to good yields and E/Z-selectivity.

5.
J Cell Mol Med ; 28(17): e70075, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39245800

RESUMO

Hyperuricemia (HUA) is characterized by elevated blood uric acid levels, which can increase the risk of erectile dysfunction (ED). Clinical studies have demonstrated satisfactory efficacy of a traditional Chinese medicine formula QYHT decoction in improving ED. Furthermore, the main monomeric components of this formula, linoleyl acetate and mandenol, demonstrate promise in the treatment of ED. This study established an ED rat model induced by HUA and the animals were administered with linoleyl acetate and mandenol. HE and TUNEL were performed to detect tissue changes, ELISA to measure the levels of serum testosterone (T), MDA, NO, CRP, and TNF-α and qPCR and WB to assess the expression levels of NLRP3, ASC, Caspase-1, JAK2, and STAT3 in whole blood. The findings showed that linoleyl acetate and mandenol improved kidney tissue morphology, reduced cell apoptosis in penile tissue, significantly increased T and NO levels, while substantially decreasing levels of MDA, CRP, and TNF-α. Meanwhile, the expression of NLRP3, ASC, and Caspase-1 mRNAs and proteins was markedly reduced, and the phosphorylation of JAK2 and STAT3 was inhibited. These findings were further validated through faecal microbiota transplantation results. Taken together, linoleyl acetate and mandenol could inhibit NLRP3 inflammasome activation, reduce inflammatory and oxidative stress responses, suppress the activity of JAK-STAT signalling pathway, ultimately providing a potential treatment for HUA-induced ED.


Assuntos
Disfunção Erétil , Hiperuricemia , Inflamassomos , Janus Quinase 2 , Proteína 3 que Contém Domínio de Pirina da Família NLR , Ratos Sprague-Dawley , Fator de Transcrição STAT3 , Transdução de Sinais , Animais , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Janus Quinase 2/metabolismo , Masculino , Inflamassomos/metabolismo , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais/efeitos dos fármacos , Ratos , Disfunção Erétil/tratamento farmacológico , Disfunção Erétil/etiologia , Disfunção Erétil/metabolismo , Hiperuricemia/tratamento farmacológico , Hiperuricemia/complicações , Apoptose/efeitos dos fármacos , Modelos Animais de Doenças
6.
Fluids Barriers CNS ; 21(1): 73, 2024 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-39289698

RESUMO

BACKGROUND: Blood-brain barrier (BBB) dysfunction has been viewed as a potential underlying mechanism of neurodegenerative disorders, possibly involved in the pathogenesis and progression of Alzheimer's disease (AD). However, a relation between BBB dysfunction and dementia with Lewy bodies (DLB) has yet to be systematically investigated. Given the overlapping clinical features and neuropathology of AD and DLB, we sought to evaluate BBB permeability in the context of DLB and determine its association with plasma amyloid-ß (Aß) using dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI). METHODS: For this prospective study, we examined healthy controls (n = 24, HC group) and patients diagnosed with AD (n = 29) or DLB (n = 20) between December 2020 and April 2022. Based on DCE-MRI studies, mean rates of contrast agent transfer from intra- to extravascular spaces (Ktrans) were calculated within regions of interest. Spearman's correlation and multivariate linear regression were applied to analyze associations between Ktrans and specific clinical characteristics. RESULTS: In members of the DLB (vs HC) group, Ktrans values of cerebral cortex (p = 0.024), parietal lobe (p = 0.007), and occipital lobe (p = 0.014) were significantly higher; and Ktrans values of cerebral cortex (p = 0.041) and occipital lobe (p = 0.018) in the DLB group were significantly increased, relative to those of the AD group. All participants also showed increased Ktrans values of parietal ( ß  = 0.391; p = 0.001) and occipital ( ß  = 0.357; p = 0.002) lobes that were significantly associated with higher scores of the Clinical Dementia Rating, once adjusted for age and sex. Similarly, increased Ktrans values of cerebral cortex ( ß  = 0.285; p = 0.015), frontal lobe ( ß  = 0.237; p = 0.043), and parietal lobe ( ß = 0.265; p = 0.024) were significantly linked to higher plasma Aß1-42/Aß1-40 ratios, after above adjustments. CONCLUSION: BBB leakage is a common feature of DLB and possibly is even more severe than in the setting of AD for certain regions of the brain. BBB leakage appears to correlate with plasma Aß1-42/Aß1-40 ratio and dementia severity.


Assuntos
Barreira Hematoencefálica , Doença por Corpos de Lewy , Imageamento por Ressonância Magnética , Humanos , Doença por Corpos de Lewy/diagnóstico por imagem , Doença por Corpos de Lewy/metabolismo , Doença por Corpos de Lewy/patologia , Barreira Hematoencefálica/metabolismo , Barreira Hematoencefálica/diagnóstico por imagem , Feminino , Masculino , Idoso , Idoso de 80 Anos ou mais , Estudos Prospectivos , Peptídeos beta-Amiloides/metabolismo , Doença de Alzheimer/metabolismo , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/patologia , Pessoa de Meia-Idade , Meios de Contraste
7.
Bioresour Technol ; 411: 131345, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39182798

RESUMO

Orotic acid is widely used in healthcare and cosmetic industries. However, orotic acid-producing microorganisms are auxotrophic, which results in inefficient microbial production. Herein, a plasmid-free, uninduced, non-auxotrophic orotic acid hyperproducer was constructed from Escherichia coli W3110. Initially, the orotic acid degradation pathway was blocked and the carbamoyl phosphate supply was enriched. Subsequently, pyr operon from Bacillus subtilis F126 was heterologously expressed and precursors' supply was optimized. Thereafter, pyrE was dynamically regulated to reconstruct the non-auxotrophic pathway. Employing fed-batch cultivation, orotic acid titer, yield, and productivity of strain Ora21 reached 182.5 g/L, 0.58 g/g, and 3.80 g/L/h, respectively, the highest levels reported so far. Finally, a novel "Chaos to Order Cycles (COC)" fermentation was developed, which effectively increased the yield to 0.63 g/g. This research is a remarkable achievement in orotic acid production by microbial fermentation and has vast potential for industrial applications.


Assuntos
Bacillus subtilis , Escherichia coli , Fermentação , Ácido Orótico , Ácido Orótico/análogos & derivados , Ácido Orótico/metabolismo , Escherichia coli/metabolismo , Escherichia coli/genética , Bacillus subtilis/genética , Bacillus subtilis/metabolismo , Engenharia Metabólica/métodos , Técnicas de Cultura Celular por Lotes
8.
ACS Nano ; 18(33): 21747-21778, 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-39105765

RESUMO

Two-dimensional (2D) materials with excellent properties and widespread applications have been explosively investigated. However, their conventional synthetic methods exhibit concerns of limited scalability, complex purification process, and incompetence of prohibiting their restacking. The blowing strategy, characterized by gas-template, low-cost, and high-efficiency, presents a valuable avenue for the synthesis of 2D-based foam materials and thereby addresses these constraints. Whereas, its comprehensive introduction has been rarely outlined so far. This review commences with a synopsis of the blowing strategy, elucidating its development history, the statics and kinetics of the blowing process, and the choice of precursor and foaming agents. Thereafter, we dwell at length on across-the-board foams enabled by the blowing route, like BxCyNz foams, carbon foams, and diverse composite foams consisting of carbon and metal compounds. Following that, a wide-ranging evaluation of the functionality of the foam products in fields such as energy storage, electrocatalysis, adsorption, etc. is discussed, revealing their distinctive strength originated from the foam structure. Finally, after concluding the current progress, we provide some personal discussions on the existing challenges and future research priorities in this rapidly developing method.

9.
BMC Cancer ; 24(1): 846, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39020272

RESUMO

BACKGROUND: Despite evidence showing a connection between inflammation and endometrial cancer (EC) risk, the surveys on genetic correlation and cohort studies investigating the impact on long-term outcomes have yet to be refined. We aimed to address the impact of inflammation factors on the pathogenesis, progression and consequences of EC. METHODS: For the genetic correlation analyses, a two-sample of Mendelian randomization (MR) study was applied to investigate inflammation-related single-nucleotide polymorphisms involved with endometrial cancer from GWAS databases. The observational retrospective study included consecutive patients diagnosed with EC (stage I to IV) with surgeries between January 2010 and October 2020 at the Cancer Hospital of Shantou University Medical College. RESULTS: The 2-sample MR surveys indicated no causal relationship between inflammatory cytokines and endometrial cancer. 780 cases (median age, 55.0 years ) diagnosed with EC were included in the cohort and followed up for an average of 6.8 years. Increased inflammatory parameters at baseline were associated with a higher FIGO stage and invasive EC risk (odds ratios [OR] 1.01 to 4.20). Multivariate-cox regression suggested that multiple inflammatory indicators were significantly associated with overall survival (OS) and progression-free survival (PFS) (P < 0.05). Nomogram models based on inflammatory risk and clinical factors were developed for OS and PFS with C-index of 0.811 and 0.789, respectively. LASSO regression for the validation supported the predictive efficacy of inflammatory and clinical factors on the long-term outcomes of EC. CONCLUSIONS: Despite the fact that the genetic surveys did not show a detrimental impact of inflammatory cytokines on the endometrial cancer risk, our cohort study suggested that inflammatory level was associated with the progression and long-term outcomes of EC. This evidence may contribute to new strategies targeted at decreasing inflammation levels during EC therapy.


Assuntos
Neoplasias do Endométrio , Estudo de Associação Genômica Ampla , Inflamação , Polimorfismo de Nucleotídeo Único , Humanos , Feminino , Neoplasias do Endométrio/genética , Neoplasias do Endométrio/patologia , Neoplasias do Endométrio/mortalidade , Pessoa de Meia-Idade , Inflamação/genética , Estudos Retrospectivos , Idoso , Análise da Randomização Mendeliana , Nomogramas , Estudos de Coortes , Adulto , Prognóstico
10.
Commun Biol ; 7(1): 920, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39080448

RESUMO

Lettuce is one of the most widely cultivated and consumed dicotyledonous vegetables globally. Despite the availability of its reference genome sequence, lettuce gene annotation remains incomplete, impeding comprehensive research and the broad application of genomic resources. Long-read RNA isoform sequencing (Iso-Seq) offers substantial advantages for analyzing RNA alternative splicing and aiding gene annotation, yet it faces throughput limitations. We present the HIT-ISOseq method tailored for bulk sample analysis, significantly enhancing RNA sequencing throughput on the PacBio platform by concatenating cDNA. Here we show, HIT-ISOseq generates 3-4 cDNA molecules per CCS read in lettuce, yielding 15.7 million long reads per PacBio Sequel II SMRT Cell 8 M. We validate its effectiveness in analyzing six lettuce tissue samples, including roots, stems, and leaves, revealing tissue-specific gene expression patterns and RNA isoforms. Leveraging diverse tissue long-read RNA sequencing, we refine the transcript annotation of the lettuce reference genome, expanding its GO and KEGG annotation repertoire. Collectively, this study serves as a foundational reference for genome annotation and the analysis of multi-sample isoform expression, utilizing high-throughput long-read transcriptome sequencing.


Assuntos
Sequenciamento de Nucleotídeos em Larga Escala , Lactuca , Análise de Sequência de RNA , Lactuca/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Análise de Sequência de RNA/métodos , RNA de Plantas/genética , Especificidade de Órgãos/genética , Regulação da Expressão Gênica de Plantas , Anotação de Sequência Molecular , Processamento Alternativo , Isoformas de RNA/genética , Genes de Plantas
11.
Acta Pharmacol Sin ; 45(11): 2300-2312, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38914677

RESUMO

Mesenchymal stem cell-derived extracellular vesicles (MSC-EVs) have obvious advantages over MSC therapy. But the strong procoagulant properties of MSC-EVs pose a potential risk of thromboembolism, an issue that remains insufficiently explored. In this study, we systematically investigated the procoagulant activity of large EVs derived from human umbilical cord MSCs (UC-EVs) both in vitro and in vivo. UC-EVs were isolated from cell culture supernatants. Mice were injected with UC-EVs (0.125, 0.25, 0.5, 1, 2, 4 µg/g body weight) in 100 µL PBS via the tail vein. Behavior and mortality were monitored for 30 min after injection. We showed that these UC-EVs activated coagulation in a dose- and tissue factor-dependent manner. UC-EVs-induced coagulation in vitro could be inhibited by addition of tissue factor pathway inhibitor. Notably, intravenous administration of high doses of the UC-EVs (1 µg/g body weight or higher) led to rapid mortality due to multiple thrombus formations in lung tissue, platelets, and fibrinogen depletion, and prolonged prothrombin and activated partial thromboplastin times. Importantly, we demonstrated that pulmonary thromboembolism induced by the UC-EVs could be prevented by either reducing the infusion rate or by pre-injection of heparin, a known anticoagulant. In conclusion, this study elucidates the procoagulant characteristics and mechanisms of large UC-EVs, details the associated coagulation risk during intravenous delivery, sets a safe upper limit for intravenous dose, and offers effective strategies to prevent such mortal risks when high doses of large UC-EVs are needed for optimal therapeutic effects, with implications for the development and application of large UC-EV-based as well as other MSC-EV-based therapies.


Assuntos
Vesículas Extracelulares , Células-Tronco Mesenquimais , Embolia Pulmonar , Tromboplastina , Cordão Umbilical , Animais , Células-Tronco Mesenquimais/metabolismo , Humanos , Vesículas Extracelulares/metabolismo , Tromboplastina/metabolismo , Cordão Umbilical/citologia , Embolia Pulmonar/metabolismo , Camundongos , Coagulação Sanguínea/efeitos dos fármacos , Masculino , Camundongos Endogâmicos C57BL , Relação Dose-Resposta a Droga
12.
J Med Chem ; 67(13): 10687-10709, 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38913701

RESUMO

UC and ALI are inflammatory diseases with limited treatment in the clinic. Herein, fragment-based anti-inflammatory agent designs were carried out deriving from cyclohexylamine/cyclobutylamine and several fragments from anti-inflammatory agents in our lab. AF-45 (IC50 = 0.53/0.60 µM on IL-6/TNF-α in THP-1 macrophages) was identified as the optimal molecule using ELISA and MTT assays from the 33 synthesized compounds. Through mechanistic studies and a systematic target search process, AF-45 was found to block the NF-κB/MAPK pathway and target IRAK4, a promising target for inflammation and autoimmune diseases. The selectivity of AF-45 targeting IRAK4 was validated by comparing its effects on other kinase/nonkinase proteins. In vivo, AF-45 exhibited a good therapeutic effect on UC and ALI, and favorable PK proprieties. Since there are currently no clinical or preclinical trials for IRAK4 inhibitors to treat UC and ALI, AF-45 provides a new lead compound or candidate targeting IRAK4 for the treatment of these diseases.


Assuntos
Lesão Pulmonar Aguda , Colite Ulcerativa , Quinases Associadas a Receptores de Interleucina-1 , Quinases Associadas a Receptores de Interleucina-1/antagonistas & inibidores , Quinases Associadas a Receptores de Interleucina-1/metabolismo , Humanos , Animais , Colite Ulcerativa/tratamento farmacológico , Lesão Pulmonar Aguda/tratamento farmacológico , Lesão Pulmonar Aguda/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/uso terapêutico , Desenho de Fármacos , Camundongos , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Anti-Inflamatórios/síntese química , Anti-Inflamatórios/química , Descoberta de Drogas , Masculino , NF-kappa B/metabolismo , NF-kappa B/antagonistas & inibidores , Relação Estrutura-Atividade , Células THP-1
13.
J Control Release ; 370: 653-676, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38735396

RESUMO

Pyroptosis, a non-apoptotic programmed cellular inflammatory death mechanism characterized by gasdermin (GSDM) family proteins, has gathered significant attention in the cancer treatment. However, the alarming clinical trial data indicates that pyroptosis-mediated cancer therapeutic efficiency is still unsatisfactory. It is essential to integrate the burgeoning biomedical findings and innovations with potent technology to hasten the development of pyroptosis-based antitumor drugs. Considering the rapid development of pyroptosis-driven cancer nanotherapeutics, here we aim to summarize the recent advances in this field at the intersection of pyroptosis and nanotechnology. First, the foundation of pyroptosis-based nanomedicines (NMs) is outlined to illustrate the reliability and effectiveness for the treatment of tumor. Next, the emerging nanotherapeutics designed to induce pyroptosis are overviewed. Moreover, the cross-talk between pyroptosis and other cell death modalities are discussed, aiming to explore the mechanistic level relationships to provide guidance strategies for the combination of different types of antitumor drugs. Last but not least, the opportunities and challenges of employing pyroptosis-based NMs in potential clinical cancer therapy are highlighted.


Assuntos
Antineoplásicos , Neoplasias , Piroptose , Piroptose/efeitos dos fármacos , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/terapia , Neoplasias/metabolismo , Neoplasias/patologia , Antineoplásicos/administração & dosagem , Antineoplásicos/uso terapêutico , Animais , Nanomedicina/métodos , Nanotecnologia/métodos , Nanopartículas/administração & dosagem
14.
J Phys Chem A ; 128(20): 4030-4037, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38722760

RESUMO

The multiphoton ionization/dissociation dynamics of molecular sulfur (S2) in the ultraviolet range of 205-300 nm is studied using velocity map ion imaging (VMI). In this one-color experiment, molecular sulfur (S2) is generated in a pulsed discharge and then photodissociated by UV radiation. At the three-photon level, superexcited states are accessed via two different resonant states: the B3Σu- (v' = 8-11) valence states at the one-photon level and a Rydberg state at the two-photon level. Among the decay processes of these superexcited states, dissociation to electronically excited S atoms is dominant as compared to autoionization to ionic states S2+ (X2Πg) at wavelengths λ < 288 nm. The anisotropy parameter extracted from these images reflects the parallel character of these electronic transitions. In contrast, autoionization is found to be particularly efficient at S(1D) and S(1S) detection wavelengths around 288 nm. Information obtained from the kinetic energy distributions of S atoms has revealed the existence of vibrationally excited S2+ (X2Πg (v+ > 11)) that dissociates to ionic products following one-photon absorption. This work also reveals many interesting features of S2 photodynamics compared to those of electronically analogous O2.

15.
Fitoterapia ; 176: 106000, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38729248

RESUMO

Five new characteristic cembrane-type diterpenoids (olibacartiols A-E, 1-5) were acquired from the gum resin of Boswellia carterii. The structures of these diterpenoids were characterized by detailed spectroscopic analysis, and compounds 1-3 were unambiguously confirmed by single-crystal X-ray diffraction experiments. The anti-inflammatory activities of the isolated compounds were evaluated using LPS-induced BV2 cell model and compounds 2-5 showed moderate NO inhibitory effects with IC50 values of 8.84 ± 1.02, 9.82 ± 1.95, 9.75 ± 2.24, and 7.39 ± 1.24 µM, respectively.


Assuntos
Anti-Inflamatórios , Boswellia , Diterpenos , Óxido Nítrico , Compostos Fitoquímicos , Resinas Vegetais , Diterpenos/farmacologia , Diterpenos/isolamento & purificação , Diterpenos/química , Boswellia/química , Óxido Nítrico/metabolismo , Estrutura Molecular , Animais , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/isolamento & purificação , Anti-Inflamatórios/química , Resinas Vegetais/química , Camundongos , Compostos Fitoquímicos/farmacologia , Compostos Fitoquímicos/isolamento & purificação , Linhagem Celular , China , Gomas Vegetais/química , Gomas Vegetais/farmacologia
16.
J Phys Chem A ; 128(17): 3351-3360, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38651288

RESUMO

H2S is being detected in the atmospheres of ever more interstellar bodies, and photolysis is an important mechanism by which it is processed. Here, we report H Rydberg atom time-of-flight measurements following the excitation of H2S molecules to selected rotational (JKaKc') levels of the 1B1 Rydberg state associated with the strong absorption feature at wavelengths of λ ∼ 129.1 nm. Analysis of the total kinetic energy release spectra derived from these data reveals that all levels predissociate to yield H atoms in conjunction with both SH(A) and SH(X) partners and that the primary SH(A)/SH(X) product branching ratio increases steeply with ⟨Jb2⟩, the square of the rotational angular momentum about the b-inertial axis in the excited state. These products arise via competing homogeneous (vibronic) and heterogeneous (Coriolis-induced) predissociation pathways that involve coupling to dissociative potential energy surfaces (PES(s)) of, respectively, 1A″ and 1A' symmetries. The present data also show H + SH(A) product formation when exciting the JKaKc' = 000 and 111 levels, for which ⟨Jb2⟩ = 0 and Coriolis coupling to the 1A' PES(s) is symmetry forbidden, implying the operation of another, hitherto unrecognized, route to forming H + SH(A) products following excitation of H2S at energies above ∼9 eV. These data can be expected to stimulate future ab initio molecular dynamic studies that test, refine, and define the currently inferred predissociation pathways available to photoexcited H2S molecules.

17.
Water Res ; 255: 121512, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38554637

RESUMO

Mud flocculation and settling play key role in understanding sediment transport cycle and affect water quality in estuaries and coastal seas. However, the morphological irregularity and structural instability of fragile mud flocs set huge obstacles for quantifying geometric property accurately and establishing reliable predicting tools in settling dynamics via previous observing strategies based on instant measured and 2-dimensional imagery floc parameterizations. Here we designed a multi-camera apparatus targeting capturing multiple angles of individual flocs, and developed a multi-view segmentation algorithm on floc images analysis. We finally accomplished batch of 3-dimensional reconstruction obtaining each settling floc's volumetric size in equilibrium flocculation. The results indicate a stable bimodal floc size distribution in equilibrium flocculation with a dominant peak of microflocs (<200 µm) and a secondary smaller peak of macroflocs (> 200 µm). The flocculi (<50 µm) shows more spherical outlines with dense structure while the larger-sized macroflocs (>200 µm) have high irregular morphologies with high porosity and visible biological debris attaching, and the microflocs (50-200 µm) tend to be irregular in shape and dense inside. The terminal settling velocity of mud flocs shows increasing with floc size in <200 µm but keeps stable around 1-2 mm s-1 after >200 µm due to the increase in size being compensated by the decrease of density according to the fractal theory on floc geometry. The higher organic matter content within larger porous flocs reduces the macroflocs effective density. These lead to high volumetric settling flux but low mass settling flux of macroflocs in natural water systems. This work provides new insight to reveal more accurate mud floc geometric parameterizations in volumetric aspect and reliable characterizations of equilibrium flocculation using a fast and sound batch of direct measuring approach. This may importantly improve the predictions of suspended mud dynamics in nature.

18.
J Am Chem Soc ; 146(10): 6422-6437, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38426858

RESUMO

The development of a new catalytic strategy plays a vital role in modern organic chemistry since it permits bond formation in an unprecedented and more efficient manner. Although the application of preformed metal complexes as π-base-activated reagents have enabled diverse transformations elegantly, the concept and strategy by directly utilizing transition metals as efficient π-Lewis base catalysts remain underdeveloped, especially in the field of asymmetric catalysis. Here, we outline our perspective on the discovery of palladium(0) as an efficient π-Lewis base catalyst, which is capable of increasing the highest occupied molecular orbital (HOMO) energy of both electron-neutral and electron-deficient 1,3-dienes and 1,3-enynes upon flexible η2-complexes formed in situ and resultant π-backdonation. Thus, fruitful carbon-carbon-forming reactions with diverse electrophiles can be achieved enantioselectively in a vinylogous addition pattern, which is conceptually different from the classical oxidative cyclization mechanism. Emphasis will be given to the concept and mechanism elucidation, catalytic features, and reaction design together with perspective on the further development of this emerging field.

20.
IUBMB Life ; 76(8): 534-547, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38380586

RESUMO

Baicalin is an active compound extracted from Scutellaria baicalensis with antioxidant and anti-inflammatory properties. Bone mesenchymal stem cells (BMSCs)-derived exosomes have shown promise for the treatment of hepatic ischemia-reperfusion (I/R) injury. This study aims to investigate the role of Baicalin-pretreated BMSCs-derived exosomes in hepatic I/R injury and its mechanisms. BMSCs were pretreated with or without Baicalin, and their exosomes (Ba-Exo and Exo) were collected and characterized. These exosomes were administered to mice via tail vein injection. Treatment with Exo and Ba-Exo significantly suppressed the elevation of ALT and AST induced by hepatic injury. Additionally, both Exo and Ba-Exo treatments resulted in a reduction in the liver weight-to-body weight ratio. RT-PCR results revealed a significant downregulation of pro-inflammatory cytokines with Exo and Ba-Exo treatment. Both Exo and Ba-Exo treatment improved the Th17/Treg cell imbalance induced by I/R and reduced hepatic injury. Additionally, exosomes were cocultured with normal liver cells, and the expression of fibroblast growth factor 21 (FGF21) in liver cells was elevated through Ba-Exo treatment. After treatment, the JAK2/STAT3 pathway was inhibited, and FOXO1 expression was upregulated. Finally, recombinant FGF21 was injected into mouse tail veins to assess its effects. Recombinant FGF21 injection further inhibited the JAK2/STAT3 pathway, increased FOXO1 expression, and improved the Th17/Treg cell imbalance. In conclusion, this study confirms the protective effects of Exo and Ba-Exo against hepatic I/R injury. Ba-Exo mitigates hepatic I/R injury, achieved through inducing FGF21 expression in liver cells, inhibiting the JAK2/STAT3 pathway, and activating FOXO1 expression. Therefore, baicalin pretreatment emerges as a promising strategy to enhance the therapeutic capability of BMSCs-derived exosomes for hepatic I/R.


Assuntos
Exossomos , Fatores de Crescimento de Fibroblastos , Flavonoides , Células-Tronco Mesenquimais , Traumatismo por Reperfusão , Transdução de Sinais , Linfócitos T Reguladores , Células Th17 , Animais , Masculino , Camundongos , Exossomos/metabolismo , Exossomos/transplante , Fatores de Crescimento de Fibroblastos/metabolismo , Flavonoides/farmacologia , Janus Quinase 2/metabolismo , Fígado/efeitos dos fármacos , Fígado/patologia , Fígado/metabolismo , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Traumatismo por Reperfusão/tratamento farmacológico , Traumatismo por Reperfusão/patologia , Traumatismo por Reperfusão/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fator de Transcrição STAT3/metabolismo , Linfócitos T Reguladores/efeitos dos fármacos , Linfócitos T Reguladores/imunologia , Células Th17/imunologia , Células Th17/efeitos dos fármacos
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