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1.
Front Physiol ; 15: 1437042, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39234311

RESUMEN

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.

2.
Fluids Barriers CNS ; 21(1): 73, 2024 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-39289698

RESUMEN

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.


Asunto(s)
Barrera Hematoencefálica , Enfermedad por Cuerpos de Lewy , Imagen por Resonancia Magnética , Humanos , Enfermedad por Cuerpos de Lewy/diagnóstico por imagen , Enfermedad por Cuerpos de Lewy/metabolismo , Enfermedad por Cuerpos de Lewy/patología , Barrera Hematoencefálica/metabolismo , Barrera Hematoencefálica/diagnóstico por imagen , Femenino , Masculino , Anciano , Anciano de 80 o más Años , Estudios Prospectivos , Péptidos beta-Amiloides/metabolismo , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/diagnóstico por imagen , Enfermedad de Alzheimer/patología , Persona de Mediana Edad , Medios de Contraste
3.
J Phys Chem A ; 2024 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-39283291

RESUMEN

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.
J Cell Mol Med ; 28(17): e70075, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39245800

RESUMEN

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.


Asunto(s)
Disfunción Eréctil , Hiperuricemia , Inflamasomas , Janus Quinasa 2 , Proteína con Dominio Pirina 3 de la Familia NLR , Ratas Sprague-Dawley , Factor de Transcripción STAT3 , Transducción de Señal , Animales , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Janus Quinasa 2/metabolismo , Masculino , Inflamasomas/metabolismo , Factor de Transcripción STAT3/metabolismo , Transducción de Señal/efectos de los fármacos , Ratas , Disfunción Eréctil/tratamiento farmacológico , Disfunción Eréctil/etiología , Disfunción Eréctil/metabolismo , Hiperuricemia/tratamiento farmacológico , Hiperuricemia/complicaciones , Apoptosis/efectos de los fármacos , Modelos Animales de Enfermedad
5.
Bioresour Technol ; 411: 131345, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-39182798

RESUMEN

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.


Asunto(s)
Bacillus subtilis , Escherichia coli , Fermentación , Ácido Orótico , Ácido Orótico/análogos & derivados , Ácido Orótico/metabolismo , Escherichia coli/metabolismo , Escherichia coli/genética , Bacillus subtilis/genética , Bacillus subtilis/metabolismo , Ingeniería Metabólica/métodos , Técnicas de Cultivo Celular por Lotes
6.
ACS Nano ; 18(33): 21747-21778, 2024 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-39105765

RESUMEN

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.

7.
Commun Biol ; 7(1): 920, 2024 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-39080448

RESUMEN

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.


Asunto(s)
Secuenciación de Nucleótidos de Alto Rendimiento , Lactuca , Análisis de Secuencia de ARN , Lactuca/genética , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Análisis de Secuencia de ARN/métodos , ARN de Planta/genética , Especificidad de Órganos/genética , Regulación de la Expresión Génica de las Plantas , Anotación de Secuencia Molecular , Empalme Alternativo , Isoformas de ARN/genética , Genes de Plantas
8.
BMC Cancer ; 24(1): 846, 2024 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-39020272

RESUMEN

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.


Asunto(s)
Neoplasias Endometriales , Estudio de Asociación del Genoma Completo , Inflamación , Polimorfismo de Nucleótido Simple , Humanos , Femenino , Neoplasias Endometriales/genética , Neoplasias Endometriales/patología , Neoplasias Endometriales/mortalidad , Persona de Mediana Edad , Inflamación/genética , Estudios Retrospectivos , Anciano , Análisis de la Aleatorización Mendeliana , Nomogramas , Estudios de Cohortes , Adulto , Pronóstico
9.
J Med Chem ; 67(13): 10687-10709, 2024 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-38913701

RESUMEN

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.


Asunto(s)
Lesión Pulmonar Aguda , Colitis Ulcerosa , Quinasas Asociadas a Receptores de Interleucina-1 , Quinasas Asociadas a Receptores de Interleucina-1/antagonistas & inhibidores , Quinasas Asociadas a Receptores de Interleucina-1/metabolismo , Humanos , Animales , Colitis Ulcerosa/tratamiento farmacológico , Lesión Pulmonar Aguda/tratamiento farmacológico , Lesión Pulmonar Aguda/metabolismo , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de Proteínas Quinasas/síntesis química , Inhibidores de Proteínas Quinasas/química , Inhibidores de Proteínas Quinasas/uso terapéutico , Diseño de Fármacos , Ratones , Antiinflamatorios/farmacología , Antiinflamatorios/uso terapéutico , Antiinflamatorios/síntesis química , Antiinflamatorios/química , Descubrimiento de Drogas , Masculino , FN-kappa B/metabolismo , FN-kappa B/antagonistas & inhibidores , Relación Estructura-Actividad , Células THP-1
10.
Acta Pharmacol Sin ; 2024 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-38914677

RESUMEN

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.

11.
Fitoterapia ; 176: 106000, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38729248

RESUMEN

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.


Asunto(s)
Antiinflamatorios , Boswellia , Diterpenos , Óxido Nítrico , Fitoquímicos , Resinas de Plantas , Diterpenos/farmacología , Diterpenos/aislamiento & purificación , Diterpenos/química , Boswellia/química , Óxido Nítrico/metabolismo , Estructura Molecular , Animales , Antiinflamatorios/farmacología , Antiinflamatorios/aislamiento & purificación , Antiinflamatorios/química , Resinas de Plantas/química , Ratones , Fitoquímicos/farmacología , Fitoquímicos/aislamiento & purificación , Línea Celular , China , Gomas de Plantas/química , Gomas de Plantas/farmacología
12.
J Phys Chem A ; 128(20): 4030-4037, 2024 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-38722760

RESUMEN

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.

13.
J Control Release ; 370: 653-676, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38735396

RESUMEN

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.


Asunto(s)
Antineoplásicos , Neoplasias , Piroptosis , Piroptosis/efectos de los fármacos , Humanos , Neoplasias/tratamiento farmacológico , Neoplasias/terapia , Neoplasias/metabolismo , Neoplasias/patología , Antineoplásicos/administración & dosificación , Antineoplásicos/uso terapéutico , Animales , Nanomedicina/métodos , Nanotecnología/métodos , Nanopartículas/administración & dosificación
14.
J Phys Chem A ; 128(17): 3351-3360, 2024 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-38651288

RESUMEN

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.

15.
Water Res ; 255: 121512, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38554637

RESUMEN

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.

16.
J Am Chem Soc ; 146(10): 6422-6437, 2024 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-38426858

RESUMEN

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.

18.
ACS Nano ; 18(9): 7046-7063, 2024 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-38381372

RESUMEN

Type 2 alveolar epithelial cell (AEC2) senescence is crucial to the pathogenesis of pulmonary fibrosis (PF). The nicotinamide adenine dinucleotide (NAD+)-consuming enzyme cluster of differentiation 38 (CD38) is a marker of senescent cells and is highly expressed in AEC2s of patients with PF, thus rendering it a potential treatment target. Umbilical cord mesenchymal stem cell (MSC)-derived extracellular vesicles (MSC-EVs) have emerged as a cell-free treatment with clinical application prospects in antiaging and antifibrosis treatments. Herein, we constructed CD38 antigen receptor membrane-modified MSC-EVs (CD38-ARM-MSC-EVs) by transfecting MSCs with a lentivirus loaded with a CD38 antigen receptor-CD8 transmembrane fragment fusion plasmid to target AEC2s and alleviate PF. Compared with MSC-EVs, the CD38-ARM-MSC-EVs engineered in this study showed a higher expression of the CD38 antigen receptor and antifibrotic miRNAs and targeted senescent AEC2s cells highly expressing CD38 in vitro and in naturally aged mouse models after intraperitoneal administration. CD38-ARM-MSC-EVs effectively restored the NAD+ levels, reversed the epithelial-mesenchymal transition phenotype, and rejuvenated senescent A549 cells in vitro, thereby mitigating multiple age-associated phenotypes and alleviating PF in aged mice. Thus, this study provides a technology to engineer MSC-EVs and support our CD38-ARM-MSC-EVs to be developed as promising agents with high clinical potential against PF.


Asunto(s)
Vesículas Extracelulares , Células Madre Mesenquimatosas , Fibrosis Pulmonar , Humanos , Ratones , Animales , Fibrosis Pulmonar/terapia , Fibrosis Pulmonar/metabolismo , Células Epiteliales Alveolares , NAD/metabolismo , Vesículas Extracelulares/metabolismo , Receptores de Antígenos/metabolismo
19.
Nanotechnology ; 35(24)2024 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-38408368

RESUMEN

The crossing of the blood-brain barrier (BBB) for conventional anticancer drugs is still a big challenge in treating glioma. The biomimetic nanoparticle delivery system has attracted increasing attention and has a promising future for crossing the BBB. Herein, we construct a multifunctional biomimetic nanoplatform using the erythrocyte membrane (EM) with the tumor-penetrating peptide iRGD (CRGDK/RGPD/EC) as a delivery, and the inner core loaded with the chemotherapeutic drug temozolomide (TMZ). The resulting biomimetic nanoparticle has perfect biocompatibility and stealth ability, which will provide more chances to escape the reticuloendothelial system (RES) entrapment, and increase the opportunity to enter the tumor site. Moreover, the decorated iRGD has been extensively used to actively targeting and deliver therapeutic agents across the BBB into glioma tissue. We show that this biomimetic delivery of TMZ with a diameter of 22 nm efficiently slowed the growth of glioblastoma multiforme (GBM) and increased the survival rate of the 30 d from 0% to 100%.


Asunto(s)
Neoplasias Encefálicas , Glioblastoma , Glioma , Humanos , Temozolomida/farmacología , Temozolomida/uso terapéutico , Glioblastoma/tratamiento farmacológico , Glioblastoma/patología , Membrana Eritrocítica , Biomimética , Línea Celular Tumoral , Neoplasias Encefálicas/tratamiento farmacológico
20.
Eur J Med Chem ; 268: 116252, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38422703

RESUMEN

The modification based on natural products is a practical way to find anti-inflammatory drugs. In this study, 26 osthole derivatives were synthesized, and their anti-inflammatory properties were evaluated. The preliminary activity study revealed that most osthole derivatives could effectively inhibit inflammatory cytokines IL-6 secretion in LPS stimulated mouse macrophages J774A.1. Compound 7m exhibited the most effective anti-inflammatory activity (RAW264.7 IL-6 IC50: 4.57 µM, 32 times more active than osthole) in vitro with no significant influence on cell proliferation. Additionally, the mechanistic analysis demonstrated that compound 7m could block MAPK signal transduction by inhibiting the phosphorylation of JNK and p38, thereby inhibiting the release of inflammatory cytokines. Moreover, in vivo functional investigations revealed that 7m could substantially reduce DSS-induced ulcerative colitis and LPS-induced acute lung injury, with good therapeutic effects. The pharmacokinetics and acute toxicity experiments proved the safety and reliability of 7min vivo. Overall, Compound 7m could further be studied as potential anti-inflammatory candidate.


Asunto(s)
Lesión Pulmonar Aguda , Colitis Ulcerosa , Colitis , Cumarinas , Animales , Ratones , Colitis Ulcerosa/inducido químicamente , Colitis Ulcerosa/tratamiento farmacológico , Lipopolisacáridos/farmacología , Interleucina-6 , Reproducibilidad de los Resultados , Antiinflamatorios/efectos adversos , Lesión Pulmonar Aguda/inducido químicamente , Lesión Pulmonar Aguda/tratamiento farmacológico , Citocinas , FN-kappa B , Ratones Endogámicos C57BL , Colitis/tratamiento farmacológico
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