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2.
Biosens Bioelectron ; 264: 116663, 2024 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-39167886

RESUMO

Surface-enhanced Raman scattering (SERS) has been extensively applied to detect complex analytes due to its ability to enhance the fingerprint signals of molecules around nanostructured metallic surfaces. Thus, it is essential to design SERS-active nanostructures with abundant electromagnetic hotspots in a probed volume according to the dimensions of the analytes, as the analytes must be located in their hotspots for maximum signal enhancement. Herein, we demonstrate a simple method for detecting robust SERS signals from multi-scaled bioanalytes, regardless of their dimensions in the liquid state, through a photothermally driven co-assembly with colloidal plasmonic nanoparticles as signal enhancers. Under resonant light illumination, plasmonic nanoparticles and analytes in the solution quickly assemble at the focused surface area by convective movements induced by the photothermal heating of the plasmonic nanoparticles without any surface modification. Such collective assemblies of plasmonic nanoparticles and analytes were optimized by varying the optical density and surface charge of the nanoparticles, the viscosity of the solvent, and the light illumination time to maximize the SERS signals. Using these light-induced co-assemblies, the intrinsic SERS signals of small biomolecules can be detected down to nanomolar concentrations based on their fingerprint spectra. Furthermore, large-sized biomarkers, such as viruses and exosomes, were successfully detected without labels, and the complexity of the collected spectra was statistically analyzed using t-distributed stochastic neighbor embedding combined with support vector machine (t-SNE + SVM). The proposed method is expected to provide a robust and convenient method to sensitively detect biologically and environmentally relevant analytes at multiple scales in liquid samples.


Assuntos
Técnicas Biossensoriais , Coloides , Nanopartículas Metálicas , Análise Espectral Raman , Análise Espectral Raman/métodos , Técnicas Biossensoriais/métodos , Coloides/química , Nanopartículas Metálicas/química , Luz , Exossomos/química , Ouro/química , Humanos , Prata/química
3.
Molecules ; 29(16)2024 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-39202910

RESUMO

Among the known planar pentacoordinate atoms, chlorine is missing due to its large radius and high electronegativity. Herein, we report the first star-like superhalogen anion D5h Cl©Li5Cl5- (1), which contains a planar pentacoordinate chlorine (ppCl) at the center. Computer structural searches and high-level calculations reveal that 1 is a true global minimum (GM) on the potential energy surfaces. Molecular dynamics simulations indicate it is kinetically stable against isomerization or decomposition. Although detailed chemical bonding analyses reveal one delocalized 6c-2e σ bond over the Cl©Li5 central unit and five delocalized 3c-2e σ bonds along the periphery, while aromaticity has very little beneficial effect on stability, instead, ionic interaction dominates the stability of the system. More encouragingly, with the large HOMO-LUMO energy gap of 7.66 eV and vertical detachment energy of 7.87 eV, the highly chemically inert 1 can be viewed as a typical superhalogen anion and is possible to be synthesized and characterized in future experiments.

4.
Zhongguo Fei Ai Za Zhi ; 27(7): 504-513, 2024 Jul 20.
Artigo em Chinês | MEDLINE | ID: mdl-39147704

RESUMO

BACKGROUND: Neoantigen reactive T cell (NRT) has the ability to inhibit the growth of tumors expressing specific neoantigens. However, due to the difficult immune infiltration and the inhibition of tumor microenvironment, the therapeutic effect of NRT in solid tumors is limited. In this study, we designed NRT cells (7×19 NRT) that can express both interleukin-7 (IL-7) and chemokine C-C motif ligand 19 (CCL19) in mouse lung cancer cells, and evaluated the difference in anti-tumor effect between 7×19 NRT cells and conventional NRT cells. METHODS: We performed next-generation sequencing and neoantigen prediction for mouse Lewis lung carcinoma (LLC), prepared RNA vaccine, cultured NRT cells, constructed retroviral vectors encoding IL-7 and CCL19, transduced NRT cells and IL-7 and CCL19 were successfully expressed, and 7×19 NRT was successfully obtained. The anti-tumor effect was evaluated in vivo and in vitro in mice. RESULTS: The 7×19 NRT cells significantly enhanced the proliferation and invasion ability of T cells by secreting IL-7 and CCL19, achieved significant tumor inhibition in the mouse lung cancer and extended the survival period of mice. The T cell infiltration into tumor tissue and the necrosis of tumor tissue increased significantly after 7×19 NRT treatment. In addition, both 7×19 NRT treatment and conventional NRT treatment were safe. CONCLUSIONS: The anti-solid tumor ability of NRT cells is significantly enhanced by the arming of IL-7 and CCL19, which is a safe and effective genetic modification of NRT.


Assuntos
Quimiocina CCL19 , Interleucina-7 , Neoplasias Pulmonares , Camundongos Endogâmicos C57BL , Linfócitos T , Animais , Camundongos , Interleucina-7/genética , Interleucina-7/imunologia , Quimiocina CCL19/genética , Quimiocina CCL19/imunologia , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/terapia , Linfócitos T/imunologia , Linhagem Celular Tumoral , Carcinoma Pulmonar de Lewis/imunologia , Carcinoma Pulmonar de Lewis/genética , Carcinoma Pulmonar de Lewis/terapia , Antígenos de Neoplasias/imunologia , Antígenos de Neoplasias/genética , Feminino , Proliferação de Células , Humanos
5.
Int Immunopharmacol ; 139: 112602, 2024 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-39033660

RESUMO

Chronic pain has emerged as a significant public health issue, seriously affecting patients' quality of life and psychological well-being, with a lack of effective pharmacological treatments. Numerous studies have indicated that macrophages play a crucial role in inflammatory pain, and targeting neuro-immune interactions for drug development may represent a promising direction for pain management. Chilobrachys jingzhao (C. jingzhao) is used as a folk medicine of the Li nationality with the efficacy of eliminating swelling, detoxicating, and relieving pain, and the related products are widely used in the market. However, the chemical constituents of C. jingzhao have not been reported, and the pharmacodynamic substance and the precise functional mechanism are unrevealed. Here we isolated a cyclic dipeptide, cyclo(L-Pro-L-Trp) (CPT) from C. jingzhao for the first time. CPT remarkably alleviated formalin-induced inflammatory pain and significantly inhibited inflammatory responses. In vivo, CPT attenuated neutrophil infiltration and plantar tissue edema and suppressed the mRNA expression of pro-inflammatory molecules. In vitro, CPT suppressed inflammation triggered by lipopolysaccharide (LPS) in both RAW 264.7 and iBMDM cells, reducing expressions of inducible nitric oxide synthase (iNOS), superoxide, and pro-inflammatory molecules. A mechanistic study revealed that CPT exerted an anti-inflammatory activity by blocking the mitogen-activated protein kinases (MAPK) and nuclear factor-kappa B (NF-κB) signaling pathways, as well as alleviating the ubiquitination of tumor necrosis factor receptor-associated factor 6 (TRAF6). Our results elucidated the pharmacodynamic material basis of C. jingzhao, and CPT can be a promising lead for alleviating inflammation and inflammatory pain.


Assuntos
Anti-Inflamatórios , Formaldeído , Inflamação , NF-kappa B , Transdução de Sinais , Fator 6 Associado a Receptor de TNF , Animais , NF-kappa B/metabolismo , Camundongos , Fator 6 Associado a Receptor de TNF/metabolismo , Anti-Inflamatórios/uso terapêutico , Anti-Inflamatórios/farmacologia , Masculino , Transdução de Sinais/efeitos dos fármacos , Inflamação/tratamento farmacológico , Células RAW 264.7 , Peptídeos Cíclicos/farmacologia , Peptídeos Cíclicos/uso terapêutico , Dor/tratamento farmacológico , Dor/induzido quimicamente , Analgésicos/uso terapêutico , Analgésicos/farmacologia , Humanos , Edema/tratamento farmacológico , Edema/induzido quimicamente , Edema/imunologia , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia
6.
Nat Commun ; 15(1): 6358, 2024 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-39069536

RESUMO

Quantum information technology offers the potential to realize unprecedented computational resources via secure channels distributing entanglement between quantum computers. Diamond, as a host to optically-accessible spin qubits, is a leading platform to realize quantum memory nodes needed to extend such quantum links. Photonic crystal (PhC) cavities enhance light-matter interaction and are essential for an efficient interface between spins and photons that are used to store and communicate quantum information respectively. Here, we demonstrate one- and two-dimensional PhC cavities fabricated in thin-film diamonds, featuring quality factors (Q) of 1.8 × 105 and 1.6 × 105, respectively, the highest Qs for visible PhC cavities realized in any material. Importantly, our fabrication process is simple and high-yield, based on conventional planar fabrication techniques, in contrast to the previous with complex undercut processes. We also demonstrate fiber-coupled 1D PhC cavities with high photon extraction efficiency, and optical coupling between a single SiV center and such a cavity at 4 K achieving a Purcell factor of 18. The demonstrated photonic platform may fundamentally improve the performance and scalability of quantum nodes and expedite the development of related technologies.

7.
Cancer Lett ; 598: 217094, 2024 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-38945204

RESUMO

Recent therapeutic strategies for the treatment of triple-negative breast cancer (TNBC) have shifted the focus from vascular growth factors to endothelial cell metabolism. This study highlights the underexplored therapeutic potential of peri-tumoral electroacupuncture, a globally accepted non-pharmacological intervention for TNBC, and molecular mechanisms. Our study showed that peri-tumoral electroacupuncture effectively reduced the density of microvasculature and enhanced vascular functionality in 4T1 breast cancer xenografts, with optimal effects on day 3 post-acupuncture. The timely integration of peri-tumoral electroacupuncture amplified the anti-tumor efficacy of paclitaxel. Multi-omics analysis revealed Glyoxalase 1 (Glo1) and the associated methylglyoxal-glycolytic pathway as key mediators of electroacupuncture-induced vascular normalization. Peri-tumoral electroacupuncture notably reduced Glo1 expression in the endothelial cells of 4T1 xenografts. Using an in vivo matrigel plug angiogenesis assay, we demonstrated that either Glo1 knockdown or electroacupuncture inhibited angiogenesis. In contrast, Glo1 overexpression increased blood vessel formation. In vitro pharmacological inhibition and genetic knockdown of Glo1 in human umbilical vein endothelial cells inhibited proliferation and promoted apoptosis via downregulating the methylglyoxal-glycolytic pathway. The study using the Glo1-silenced zebrafish model further supported the role of Glo1 in vascular development. This study underscores the pivotal role of Glo1 in peri-tumoral electroacupuncture, spotlighting a promising avenue for enhancing vascular normalization and improving TNBC treatment outcomes.


Assuntos
Eletroacupuntura , Glicólise , Lactoilglutationa Liase , Neovascularização Patológica , Neoplasias de Mama Triplo Negativas , Animais , Feminino , Humanos , Camundongos , Linhagem Celular Tumoral , Proliferação de Células , Eletroacupuntura/métodos , Células Endoteliais/metabolismo , Células Endoteliais da Veia Umbilical Humana , Lactoilglutationa Liase/metabolismo , Lactoilglutationa Liase/genética , Camundongos Endogâmicos BALB C , Neovascularização Patológica/metabolismo , Paclitaxel/farmacologia , Aldeído Pirúvico/metabolismo , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/metabolismo , Neoplasias de Mama Triplo Negativas/patologia , Neoplasias de Mama Triplo Negativas/terapia , Ensaios Antitumorais Modelo de Xenoenxerto , Peixe-Zebra
8.
J Craniofac Surg ; 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38809062

RESUMO

Despite their limitations, epidemiological studies provide information useful for formulating effective and efficient injury prevention strategies. The aim is to carry out an epidemiology study of maxillofacial fracture in Xijing Hospital. Level of Evidence: Level II-therapeutic study.

9.
Chem Commun (Camb) ; 60(49): 6300-6303, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38818579

RESUMO

Herein we report a square-like D4h H©K4H4- anion with one planar tetracoordinate hydrogen (ptH) center, which is the global minimum (GM) structure and possesses good dynamic stability. The planar structure of the system is preserved by four peripheral K-H-K three-center two-electron (3c-2e) σ bonds together with one 5c-2e σ bond over the HK4 core. The multicenter ionic bonds dominate the stability of ptH, while the contribution of qualitative σ aromaticity is extremely limited.

10.
ACS Appl Mater Interfaces ; 16(22): 28645-28654, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38787734

RESUMO

The chemical stability and energy density of redox couples are crucial factors in enhancing the durability and cost competitiveness of aqueous flow batteries. This study proposed integrating functional groups to viologen anolyte to increase its solubility and, consequently, energy density and stability for prolonged performance. Specifically, sulfonate and ester groups were selectively incorporated at the nitrogen sites of viologen to enhance solubility, leveraging their asymmetry and double hydrophilicity. Furthermore, an alpha-methyl group was introduced between the bipyridine and ester groups to enhance the chemical stability by preventing stacking and dimerization that can lead to irreversible degradation. The modified viologen demonstrated a remarkable solubility of 3.0 M in deionized water, corresponding to a volumetric capacity of 80.404 Ah L-1. Additionally, the designed viologen exhibits outstanding retention of 92.4% after 200 cycles with a minimal capacity fading rate of 0.055% per cycle in a 0.1 M flow cell test.

11.
J Environ Manage ; 361: 121258, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38815428

RESUMO

The rising accumulation of poly(ethylene terephthalate) (PET) waste presents an urgent ecological challenge, necessitating an efficient and economical treatment technology. Here, we developed chemical-biological module clusters that perform chemical pretreatment, enzymatic degradation, and microbial assimilation for the large-scale treatment of PET waste. This module cluster included (i) a chemical pretreatment that involves incorporating polycaprolactone (PCL) at a weight ratio of 2% (PET:PCL = 98:2) into PET via mechanical blending, which effectively reduces the crystallinity and enhances degradation; (ii) enzymatic degradation using Thermobifida fusca cutinase variant (4Mz), that achieves complete degradation of pretreated PET at 300 g/L PET, with an enzymatic loading of 1 mg protein per gram of PET; and (iii) microbial assimilation, where Rhodococcus jostii RHA1 metabolizes the degradation products, assimilating each monomer at a rate above 90%. A comparative life cycle assessment demonstrated that the carbon emissions from our module clusters (0.25 kg CO2-eq/kg PET) are lower than those from other established approaches. This study pioneers a closed-loop system that seamlessly incorporates pretreatment, degradation, and assimilation processes, thus mitigating the environmental impacts of PET waste and propelling the development of a circular PET economy.


Assuntos
Biodegradação Ambiental , Poliésteres , Polietilenotereftalatos , Polietilenotereftalatos/química , Polietilenotereftalatos/metabolismo , Poliésteres/metabolismo , Poliésteres/química , Hidrolases de Éster Carboxílico
12.
Phytomedicine ; 129: 155555, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38579641

RESUMO

BACKGROUND: Ischemic stroke is a leading cause of death and long-term disability worldwide. Studies have suggested that cerebral ischemia induces massive mitochondrial damage. Valerianic acid A (VaA) is the main active ingredient of valerianic acid with neuroprotective activity. PURPOSE: This study aimed to investigate the neuroprotective effects of VaA with ischemic stroke and explore the underlying mechanisms. METHOD: In this study, we established the oxygen-glucose deprivation and reperfusion (OGD/R) cell model and the middle cerebral artery occlusion and reperfusion (MCAO/R) animal model in vitro and in vivo. Neurological behavior score, 2, 3, 5-triphenyl tetrazolium chloride (TTC) staining and Hematoxylin and Eosin (HE) Staining were used to detect the neuroprotection of VaA in MCAO/R rats. Also, the levels of ROS, mitochondrial membrane potential (MMP), and activities of NAD+ were detected to reflect mitochondrial function. Mechanistically, gene knockout experiments, transfection experiments, immunofluorescence, DARTS, and molecular dynamics simulation experiments showed that VaA bound to IDO1 regulated the kynurenine pathway of tryptophan metabolism and prevented Stat3 dephosphorylation, promoting Stat3 activation and subsequent transcription of the mitochondrial fusion-related gene Opa1. RESULTS: We showed that VaA decreased the infarct volume in a dose-dependent manner and exerted neuroprotective effects against reperfusion injury. Furthermore, VaA promoted Opa1-related mitochondrial fusion and reversed neuronal mitochondrial damage and loss after reperfusion injury. In SH-SY5Y cells, VaA (5, 10, 20 µM) exerted similar protective effects against OGD/R-induced injury. We then examined the expression of significant enzymes regulating the kynurenine (Kyn) pathway of the ipsilateral brain tissue of the ischemic stroke rat model, and these enzymes may play essential roles in ischemic stroke. Furthermore, we found that VaA can bind to the initial rate-limiting enzyme IDO1 in the Kyn pathway and prevent Stat3 phosphorylation, promoting Stat3 activation and subsequent transcription of the mitochondrial fusion-related gene Opa1. Using in vivo IDO1 knockdown and in vitro IDO1 overexpressing models, we demonstrated that the promoted mitochondrial fusion and neuroprotective effects of VaA were IDO1-dependent. CONCLUSION: VaA administration improved neurological function by promoting mitochondrial fusion through the IDO1-mediated Stat3-Opa1 pathway, indicating its potential as a therapeutic drug for ischemic stroke.


Assuntos
Indolamina-Pirrol 2,3,-Dioxigenase , Fármacos Neuroprotetores , Fator de Transcrição STAT3 , Transdução de Sinais , Animais , Masculino , Ratos , Modelos Animais de Doenças , Indolamina-Pirrol 2,3,-Dioxigenase/metabolismo , Infarto da Artéria Cerebral Média/tratamento farmacológico , AVC Isquêmico/tratamento farmacológico , Cinurenina/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Dinâmica Mitocondrial/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Ratos Sprague-Dawley , Traumatismo por Reperfusão/tratamento farmacológico , Transdução de Sinais/efeitos dos fármacos , Fator de Transcrição STAT3/metabolismo , Triterpenos/farmacologia
13.
Int J Mol Sci ; 25(5)2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38474066

RESUMO

Planar tetracoordinate silicon, germanium, tin, and lead (ptSi/Ge/Sn/Pb) species are scarce and exotic. Here, we report a series of penta-atomic ptSi/Ge/Sn/Pb XB2Bi2 (X = Si, Ge, Sn, Pb) clusters with 20 valence electrons (VEs). Ternary XB2Bi2 (X = Si, Ge, Sn, Pb) clusters possess beautiful fan-shaped structures, with a Bi-B-B-Bi chain surrounding the central X core. The unbiased density functional theory (DFT) searches and high-level CCSD(T) calculations reveal that these ptSi/Ge/Sn/Pb species are the global minima on their potential energy surfaces. Born-Oppenheimer molecular dynamics (BOMD) simulations indicate that XB2Bi2 (X = Si, Ge, Sn, Pb) clusters are robust. Bonding analyses indicate that 20 VEs are perfect for the ptX XB2Bi2 (X = Si, Ge, Sn, Pb): two lone pairs of Bi atoms; one 5c-2e π, and three σ bonds (two Bi-X 2c-2e and one B-X-B 3c-2e bonds) between the ligands and X atom; three 2c-2e σ bonds and one delocalized 4c-2e π bond between the ligands. The ptSi/Ge/Sn/Pb XB2Bi2 (X = Si, Ge, Sn, Pb) clusters possess 2π/2σ double aromaticity, according to the (4n + 2) Hückel rule.


Assuntos
Tetranitrato de Pentaeritritol , Rubiaceae , Gravidez , Feminino , Humanos , Elétrons , Chumbo , Simulação de Dinâmica Molecular , Parto
14.
Medicine (Baltimore) ; 103(6): e37038, 2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38335431

RESUMO

Colorectal cancer (CRC) remains a significant global health concern, as characterized by its high mortality rate ranking second among all the leading causes of death. The liver serves as the primary site of CRC metastasis, and the occurrence of liver metastasis is a significant contributor to mortality among patients diagnosed with CRC. The survival rate of patients with colorectal liver metastasis has significantly increased with the advancement of comprehensive tumor therapy. However, radical surgery remains the key factor. Since there are frequently multiple liver metastases, which are prone to recurrence after surgery, it is crucial to preserve as much liver parenchyma as possible without affecting the prognosis. The issue of surgical margins plays a crucial role in this regard. In this review, we begin by examining the occurrence of positive surgical margins in liver metastases of patients diagnosed with CRC. We aim to define positive margins in hepatic surgery, examine the relationship between margins and prognosis and establish a foundation for future research in this field.


Assuntos
Neoplasias Colorretais , Neoplasias Hepáticas , Humanos , Margens de Excisão , Hepatectomia , Neoplasias Colorretais/patologia , Neoplasias Hepáticas/patologia , Prognóstico
15.
Front Oncol ; 14: 1343157, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38410104

RESUMO

Castleman disease (CD), a distinct lymphoproliferative disorder, is infrequently encountered in clinical practice and poses significant diagnostic challenges. We present the case of a 48-year-old asymptomatic female, admitted for evaluation of a hepatic mass detected in the liver's right lobe. Preoperative laboratory tests were within normal limits. Diagnostic imaging, including contrast-enhanced magnetic resonance imaging (MRI), was suggestive of hepatocellular carcinoma. Furthermore, contrast-enhanced abdominal computed tomography (CT) scans were indicative of hepatic malignancy. Subsequently, the patient underwent laparoscopic surgery targeting a retroperitoneal mass. During the surgical procedure, it was observed that the tumor was a retroperitoneal mass situated posterior to the liver, exhibiting localized adhesion to hepatic tissue. The postoperative histopathological analysis revealed the mass to be hyaline-vascular type Castleman disease (HV-CD), thereby refuting the initial diagnosis of a hepatic malignancy. This case underscores the complexity of diagnosing retroperitoneal Castleman disease, particularly when it masquerades as a hepatic tumor.

16.
Nanoscale ; 16(9): 4778-4786, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38305072

RESUMO

It is highly challenging to control (stop and resume as needed) molecular rotors because their intramolecular rotations are electronically enabled by delocalized σ bonding, and the desired control needs to be able to destroy and restore such σ bonding, which usually means difficult chemical manipulation (substitution or doping atom). In this work, we report CBe4H6, a molecular rotor that can be controlled independently of chemical manipulation. This molecule exhibited the uninterrupted free rotation of Be and H atoms around the central carbon in first-principles molecular dynamics simulations at high temperatures (600 and 1000 K), but the rotation cannot be witnessed in the simulation at room temperature (298 K). Specifically, when a C-H bond in the CBe4H6 molecule adopts the equatorial configuration at 298 K, it destroys the central delocalized σ bonding and blocks the intramolecular rotation (the rotor is turned "OFF"); when it can adopt the axial configuration at 600 and 1000 K, the central delocalized σ bonding can be restored and the intramolecular rotation can be resumed (the rotor is turned "ON"). Neutral CBe4H6 is thermodynamically favorable and electronically stable, as reflected by a wide HOMO-LUMO gap of 7.99 eV, a high vertical detachment energy of 9.79 eV, and a positive electron affinity of 0.24 eV, so it may be stable enough for the synthesis, not only in the gas phase, but also in the condensed phase.

17.
Chem Commun (Camb) ; 60(10): 1341-1344, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38197330

RESUMO

Replacing one of the peripheral Se with a Se2 bridge is an effective strategy to flatten the C4v CB4Se4 cluster. The global minimum of CB4Se5 contains one fan-shaped planar tetracoordinate carbon (ptC) CB4 core, possessing double 2π + 6σ aromaticity. The peripheral Se2 bridge is dexterous and crucial for the stability of CB4Se5.

18.
Food Chem X ; 21: 101058, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38178927

RESUMO

Tea (Camellia sinensis L.) flower polysaccharides (TFPS) have various health-promoting functions. In the present work, the structure of a purified TFPS fraction, namely TFPS-1-3p, and its in vitro digestive properties were investigated. The results demonstrated that TFPS-1-3p was a typical heteropolysaccharide consisting of rhamnose (Rha), arabinose (Ara), galactose (Gal) and galacturonic acid (GalA) with a molecular weight of 47.77 kDa. The backbone of TFPS-1-3p contained â†’ 4)-α-d-GalpA(-6-OMe)-(1 â†’ 4)-α-GalpA-(1 â†’ and â†’ 4)-α-d-GalpA(-6-OMe)-(1 â†’ 2,4)-α-l-Rhap-(1 â†’ linkages. The branch linkages in TFPS-1-3p contained â†’ 6)-ß-d-Galp-(1→, →3,6)-ß-d-Galp-(1→, →5)-α-l-Araf-(1 â†’ and â†’ 3,5)-α-l-Araf-(1 â†’. Subsequently, TFPS-1-3p could not be degraded under simulated human gastrointestinal conditions but could be of use to human fecal microbes, thereby lowering the pH and increasing the production of short-chain fatty acids (SCFAs) of the gut microenvironment and altering the composition of the gut microbiota. The relative abundance of Fusobacterium_mortiferum Megasphaera_elsdenii_DSM_20460, Bacteroides thetaiotaomicron, Bacteroides plebeius and Collinsella aerofaciens increased significantly, potentially contributing to the degradation of TFPS-1-3p.

19.
Phys Chem Chem Phys ; 26(7): 6049-6057, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38295372

RESUMO

Boron-based complex clusters are a fertile ground for the exploration of exotic chemical bonding and dynamic structural fluxionality. Here we report on the computational design of a ternary MgTa2B6 cluster via global structural searches and quantum chemical calculations. The cluster turns out to be a new member of the molecular rotor family, closely mimicking a turning clock at the subnanoscale. It is composed of a hexagonal B6 ring with a capping Ta atom at the top and bottom, whereas the Mg atom is linked to one Ta site as a radial Ta-Mg dimer. These components serve as the dial, axis, and hand of a nanoclock, respectively. Chemical bonding analyses reveal that the inverse sandwich Ta2B6 motif in the cluster features 6π/6σ double aromaticity, whose electron counting conforms to the (4n + 2) Hückel rule. The Ta-Mg dimer has a Lewis-type σ bond, and the Mg site has negligible bonding with B6 ring. The ternary cluster can be formulated as an [Mg]0[Ta2B6]0 complex. Molecular dynamics simulations suggest that the cluster is structurally fluxional analogous to a nanoclock, even at a low temperature of 100 K. The Ta-Mg hand turns almost freely around the Ta2 axis and along the B6 dial. The tiny intramolecular rotation barrier is less than 0.3 kcal mol-1, being dictated by the bonding nature of double 6π/6σ aromaticity. The present system offers a new type of molecular rotor in physical chemistry.

20.
Phytochemistry ; 219: 113974, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38211847

RESUMO

Twenty-one angular dihydropyranocoumarins and a linear furanocoumarin, including four previously undescribed compounds (1-4), were isolated from the flowers of Peucedanum japonicum (Umbelliferae). The structures of 1-4, along with their absolute stereochemistry, were determined to be (3'S,4'S)-3'-O-propanoyl-4'-O-(3‴-methyl-2‴-butenoyl)khellactone (1), (3'S,4'S)-3'-O-propanoyl-4'-O-(2‴-methyl-2‴Z-butenoyl)khellactone (2), (3'S,4'S)-3'-O-propanoyl-4'-O-(2‴-methylbutanoyl)khellactone (3), and (3'S,4'S)-3'-O-(2″-methylpropanoyl)-4'-O-(3‴-methyl-2‴-butenoyl)khellactone (4) using one- and two-dimensional nuclear magnetic resonance, high-resolution electrospray ionization mass spectroscopy, and electronic circular dichroism spectroscopy. In addition, the absolute configuration of the three angular dihydropyranocoumarins (5-7) was determined for the first time in this study. Among the previously reported compounds isolated in this study, 8 and 9 were isolated for the first time from the genus Peucedanum, whereas 10 and 11 were previously unreported and had not been isolated from P. japonicum to date. Furthermore, all isolated compounds were evaluated for their aldo-keto reductase 1C1 inhibitory activities on A549 human non-small-cell lung cancer cells. Compounds 10 and 12 exhibited substantial AKR1C1 inhibitory activities with IC50 values of 35.8 ± 0.9 and 44.2 ± 1.5 µM, respectively.


Assuntos
Apiaceae , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Flores , Aldo-Ceto Redutases
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