Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 11 de 11
Filtrar
Más filtros










Base de datos
Intervalo de año de publicación
1.
Inorg Chem ; 63(25): 11572-11582, 2024 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-38866714

RESUMEN

Recently synthesized two-dimensional (2D) monolayer quasi-hexagonal-phase fullerene (qHPC60) demonstrates excellent thermodynamic stability. Within this monolayer, each fullerene cluster is surrounded by six adjacent C60 cages along an equatorial plane and is connected by both C-C single bonds and [2 + 2] cycloaddition bonds that serve as bridges. In this study, we investigate the stability mechanism of the 2D qHPC60 monolayer by examining the electronic structure and chemical bonding through state-of-the-art theoretical methodologies. Density functional theory (DFT) studies reveal that 2D qHPC60 possesses a moderate direct electronic band gap of 1.46 eV, close to the experimental value (1.6 eV). It is found that the intermolecular bridge bonds play a crucial role in enhancing the charge flow and redistribution among C60 cages, leading to the formation of dual π-aromaticity within the C60 sphere and stabilizing the 2D framework structure. Furthermore, we identify a series of delocalized superatom molecular orbitals (SAMOs) within the 2D qHPC60 monolayer, exhibiting atomic orbital-like behavior and hybridization to form nearly free-electron (NFE) bands with σ/π bonding and σ*/π* antibonding properties. Our findings provide insights into the design and potential applications of NFE bands derived from SAMOs in 2D qHPC60 monolayers.

2.
Chem Sci ; 15(25): 9733-9741, 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38939145

RESUMEN

Highly efficient degradation of antibiotics is a huge challenge due to the extremely stable molecules and the potential for biological resistance. However, conventional degradation methods are limited to lower degradation rate, higher energy consumption and secondary pollution. Herein, we report a new Cu-based metal-organic framework (MOF), featuring classical planar trinuclear [Cu3(µ3-O)]4+ clusters within the pores. The presence of the rich open metal sites and the large pore ratio, as well as the high catalytic activity of Cu2+ ions, are conducive to boosting the degradation of various antibiotics (>95%) under the activation of peroxymonosulfate. Remarkably, this is the first MOF to achieve such exceptional catalytic performance under neutral and even alkaline conditions, which exceeds those of most reported materials. Mechanism investigation demonstrates that multiple active species were produced and promoted the degradation synergistically during the advanced oxidation processes.

3.
Integr Med Res ; 13(2): 101039, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38746044

RESUMEN

Background: Chronic fatigue is a predominant symptom of post COVID-19 condition, or long COVID. We aimed to evaluate the efficacy and safety of Traditional, Complementary and Integrative Medicine (TCIM) for fatigue post COVID-19 infection. Methods: Ten English and Chinese language databases and grey literature were searched up to 12 April 2023 for randomized controlled trials (RCTs). Cochrane "Risk of bias" (RoB) tool was applied. Evidence certainty was assessed using Grading of Recommendations Assessment, Development, and Evaluation (GRADE). Effect estimates were presented as risk ratio (RR) or mean difference (MD) with 95% confidence interval (CI). Results: Thirteen RCTs with 1632 participants were included. One RCT showed that Bufei Huoxue herbal capsules reduced fatigue (n=129, MD -14.90, 95%CI -24.53 to -5.27), one RCT reported that Ludangshen herbal liquid lowered fatigue (n=184, MD -1.90, 95%CI -2.38 to -1.42), and the other one RCT shown that fatigue disappearance rate was higher with Ludangshen herbal liquid (n=184, RR 4.19, 95%CI 2.06 to 8.53). Compared to traditional Chinese medicine rehabilitation (TCM-rahab) alone, one RCT showed that fatigue symptoms were lower following Qingjin Yiqi granules plus TCM-rehab (n=388, MD -0.48, 95%CI -0.50 to -0.46). Due to concerns with RoB and/or imprecision, the certainty in this evidence was low to very low. No serious adverse events was reported. Conclusions: Limited evidence suggests that various TCIM interventions might reduce post COVID-19 fatigue. Larger, high quality RCTs of longer duration are required to confirm these preliminary findings. Study Registration: The protocol of this review has been registered at PROSPERO: CRD42022384136.

4.
Am J Reprod Immunol ; 91(4): e13847, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38661639

RESUMEN

PROBLEM: Polycystic ovary syndrome (PCOS), a prevalent endocrine-metabolic disorder, presents considerable therapeutic challenges due to its complex and elusive pathophysiology. METHOD OF STUDY: We employed three machine learning algorithms to identify potential biomarkers within a training dataset, comprising GSE138518, GSE155489, and GSE193123. The diagnostic accuracy of these biomarkers was rigorously evaluated using a validation dataset using area under the curve (AUC) metrics. Further validation in clinical samples was conducted using PCR and immunofluorescence techniques. Additionally, we investigate the complex interplay among immune cells in PCOS using CIBERSORT to uncover the relationships between the identified biomarkers and various immune cell types. RESULTS: Our analysis identified ACSS2, LPIN1, and NR4A1 as key mitochondria-related biomarkers associated with PCOS. A notable difference was observed in the immune microenvironment between PCOS patients and healthy controls. In particular, LPIN1 exhibited a positive correlation with resting mast cells, whereas NR4A1 demonstrated a negative correlation with monocytes in PCOS patients. CONCLUSION: ACSS2, LPIN1, and NR4A1 emerge as PCOS-related diagnostic biomarkers and potential intervention targets, opening new avenues for the diagnosis and management of PCOS.


Asunto(s)
Biomarcadores , Mitocondrias , Miembro 1 del Grupo A de la Subfamilia 4 de Receptores Nucleares , Síndrome del Ovario Poliquístico , Humanos , Síndrome del Ovario Poliquístico/inmunología , Síndrome del Ovario Poliquístico/metabolismo , Femenino , Biomarcadores/metabolismo , Mitocondrias/metabolismo , Aprendizaje Automático , Adulto , Mastocitos/inmunología , Mastocitos/metabolismo
5.
J Phys Chem Lett ; 15(11): 3055-3060, 2024 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-38466221

RESUMEN

Precise characterization of archetypal systems of aqueous hydrogen-bonding networks is essential for developing accurate potential functions and universal models of water. The structures of water clusters (H2O)n (n = 2-9) have been verified recently through size-specific infrared spectroscopy with a vacuum ultraviolet free electron laser (VUV-FEL) and quantum chemical studies. For (H2O)10, the pentagonal prism and butterfly motifs were proposed to be important building blocks and were observed in previous experiments. Here we report the size-specific infrared spectra of (H2O)10 via a joint experimental and theoretical study. Well-resolved spectra provide a unique signature for the coexistence of pentagonal prism and butterfly motifs. These (H2O)10 motifs develop from the dominant structures of (H2O)n (n = 8, 9) clusters. This work provides an intriguing prelude to the diverse structure of liquid water and opens avenues for size-dependent measurement of larger systems to understand the stepwise formation mechanism of hydrogen-bonding networks.

6.
Sci Rep ; 14(1): 4459, 2024 02 23.
Artículo en Inglés | MEDLINE | ID: mdl-38396064

RESUMEN

As the largest transporter family impacting on tumor genesis and development, the prognostic value of solute carrier (SLC) members has not been elucidated in colorectal cancer (CRC). We aimed to identify a prognostic signature from the SLC members and comprehensively analyze their roles in CRC. Firstly, we downloaded transcriptome data and clinical information of CRC samples from GEO (GSE39582) and TCGA as training and testing dataset, respectively. We extracted the expression matrix of SLC genes and established a prognostic model by univariate and multivariate Cox regression. Afterwards, the low-risk and high-risk group were identified. Then, the differences of prognosis traits, transcriptome features, clinical characteristics, immune infiltration and drug sensitivity between the two groups were explored. Furthermore, molecular subtyping was also implemented by non-negative matrix factorization (NMF). Finally, we studied the expression of the screened SLC genes in CRC tumor tissues and normal tissues as well as investigated the role of SLC12A2 by loss of function and gain of function. As a result, we developed a prognostic risk model based on the screened 6-SLC genes (SLC39A8, SLC2A3, SLC39A13, SLC35B1, SLC4A3, SLC12A2). Both in the training and testing sets, CRC patients in the high-risk group had the poorer prognosis and were in the more advanced pathological stage. What's more, the high-risk group were enriched with CRC progression signatures and immune infiltration. Two groups showed different drug sensitivity. On the other hand, two distinct subclasses (C1 and C2) were identified based on the 6 SLC genes. CRC patients in the high-risk group and C1 subtype had a worse prognosis. Furthermore, we found and validated that SLC12A2 was steadily upregulated in CRC. A loss-of-function study showed that knockdown of SLC12A2 expression restrained proliferation and stemness of CRC cells while a gain-of-function study showed the contrary results. Hence, we provided a 6-SLC gene signature for prognosis prediction of CRC patients. At the same time, we identified that SLC12A2 could promote tumor progression in CRC, which may serve as a potential therapeutic target.


Asunto(s)
Neoplasias Colorrectales , Miembro 2 de la Familia de Transportadores de Soluto 12 , Humanos , Algoritmos , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/genética , Proteínas de Transporte de Membrana , Fenotipo , Pronóstico
7.
Environ Sci Technol ; 58(8): 3974-3984, 2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38306233

RESUMEN

In contaminated water and soil, little is known about the role and mechanism of the biometabolic molecule siderophore desferrioxamine-B (DFO) in the biogeochemical cycle of uranium due to complicated coordination and reaction networks. Here, a joint experimental and quantum chemical investigation is carried out to probe the biomineralization of uranyl (UO22+, referred to as U(VI) hereafter) induced by Shewanella putrefaciens (abbreviated as S. putrefaciens) in the presence of DFO and Fe3+ ion. The results show that the production of mineralized solids {hydrogen-uranium mica [H2(UO2)2(PO4)2·8H2O]} via S. putrefaciens binding with UO22+ is inhibited by DFO, which can both chelate preferentially UO22+ to form a U(VI)-DFO complex in solution and seize it from U(VI)-biominerals upon solvation. However, with Fe3+ ion introduced, the strong specificity of DFO binding with Fe3+ causes re-emergence of biomineralization of UO22+ {bassetite [Fe(UO2)2(PO4)2·8(H2O)]} by S. putrefaciens, owing to competitive complexation between Fe3+ and UO22+ for DFO. As DFO possesses three hydroxamic functional groups, it forms hexadentate coordination with Fe3+ and UO22+ ions via these functional groups. The stability of the Fe3+-DFO complex is much higher than that of U(VI)-DFO, resulting in some DFO-released UO22+ to be remobilized by S. putrefaciens. Our finding not only adds to the understanding of the fate of toxic U(VI)-containing substances in the environment and biogeochemical cycles in the future but also suggests the promising potential of utilizing functionalized DFO ligands for uranium processing.


Asunto(s)
Shewanella putrefaciens , Uranio , Biomineralización , Deferoxamina/metabolismo , Deferoxamina/farmacología , Shewanella putrefaciens/metabolismo , Sideróforos/metabolismo , Sideróforos/farmacología , Uranio/química , Compuestos de Hierro/química
8.
Nat Commun ; 15(1): 1363, 2024 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-38355599

RESUMEN

The study of cross-catenated metallacages, which are complex self-assembly systems arising from multiple supramolecular interactions and hierarchical assembly processes, is currently lacking but could provide facile insights into achieving more precise control over low-symmetry/high-complexity hierarchical assembly systems. Here, we report a cross-catenane formed between two position-isomeric Pt(II) metallacages in the solid state. These two metallacages formed [2]catenanes in solution, whereas a 1:1 mixture selectively formed a cross-catenane in crystals. Varied temperature nuclear magnetic resonance experiments and time-of-flight mass spectra are employed to characterize the cross-catenation in solutions, and the dynamic library of [2]catenanes are shown. Additionally, we searched for the global-minimum structures of three [2]catenanes and re-optimized the low-lying structures using density functional theory calculations. Our results suggest that the binding energy of cross-catenanes is significantly larger than that of self-catenanes within the dynamic library, and the selectivity in crystallization of cross-catenanes is thermodynamic. This study presents a cross-catenated assembly from different metallacages, which may provide a facile insight for the development of low-symmetry/high-complexity self-assemble systems.

9.
Biomolecules ; 14(1)2024 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-38254716

RESUMEN

BACKGROUND: While extensive research highlighted the involvement of metabolism and immune cells in female reproductive diseases, causality remains unestablished. METHODS: Instrumental variables for 486 circulating metabolites (N = 7824) and 731 immunophenotypes (N = 3757) were derived from a genome-wide association study (GWAS) meta-analysis. FinnGen contributed data on 14 female reproductive disorders. A bidirectional two-sample Mendelian randomization study was performed to determine the relationships between exposures and outcomes. The robustness of results, potential heterogeneity, and horizontal pleiotropy were examined through sensitivity analysis. RESULTS: High levels of mannose were found to be causally associated with increased risks of gestational diabetes (GDM) (OR [95% CI], 6.02 [2.85-12.73], p = 2.55 × 10-6). A genetically predicted elevation in the relative count of circulating CD28-CD25++CD8+ T cells was causally related to increased female infertility risk (OR [95% CI], 1.26 [1.14-1.40], p = 1.07 × 10-5), whereas a high absolute count of NKT cells reduced the risk of ectopic pregnancy (OR [95% CI], 0.87 [0.82-0.93], p = 5.94 × 10-6). These results remained consistent in sensitivity analyses. CONCLUSIONS: Our study supports mannose as a promising GDM biomarker and intervention target by integrating metabolomics and genomics.


Asunto(s)
Linfocitos T CD8-positivos , Diabetes Gestacional , Embarazo , Humanos , Femenino , Estudio de Asociación del Genoma Completo , Manosa , Análisis de la Aleatorización Mendeliana , Antígenos CD28
10.
Immun Ageing ; 21(1): 10, 2024 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-38279177

RESUMEN

BACKGROUND: Age-related changes in the ovarian microenvironment are linked to impaired fertility in women. Macrophages play important roles in ovarian tissue homeostasis and immune surveillance. However, the impact of aging on ovarian macrophage function and ovarian homeostasis remains poorly understood. METHODS: Senescence-associated beta-galactosidase staining, immunohistochemistry, and TUNEL staining were used to assess senescence and apoptosis, respectively. Flow cytometry was employed to evaluate mitochondrial membrane potential (MMP) and apoptosis in granulosa cells lines (KGN), and macrophages phagocytosis. After a 2-month treatment with low molecular weight Chitosan (LMWC), ovarian tissues from mice were collected for comprehensive analysis. RESULTS: Compared with the liver and uterus, the ovary displayed accelerated aging in an age-dependent manner, which was accompanied by elevated levels of inflammatory factors and apoptotic cells, and impaired macrophage phagocytic activity. The aged KGN cells exhibited elevated reactive oxygen species (ROS) and apoptotic levels alongside decreased MMP. H2O2-induced aging macrophages showed reduced phagocytosis function. Moreover, there were excessive aging macrophages with impaired phagocytosis in the follicular fluid of patients with diminished ovarian reserve (DOR). Notably, LMWC administration alleviated ovarian aging by enhancing macrophage phagocytosis and promoting tissue homeostasis. CONCLUSIONS: Aging ovarian is characterized by an accumulation of aging and apoptotic granulosa cells, an inflammatory response and macrophage phagocytosis dysfunction. In turn, impaired phagocytosis of macrophage contributes to insufficient clearance of aging and apoptotic granulosa cells and the increased risk of DOR. Additionally, LMWC emerges as a potential therapeutic strategy for age-related ovarian dysfunction.

11.
Am J Physiol Cell Physiol ; 326(2): C429-C441, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38105757

RESUMEN

Senile osteoporosis increases fracture risks. Bone marrow stromal cells (BMSCs) are sensitive to aging. Deep insights into BMSCs aging are vital to elucidate the mechanisms underlying age-related bone loss. Recent advances showed that osteoporosis is associated with aberrant DNA methylation of many susceptible genes. Galectin-1 (Gal-1) has been proposed as a mediator of BMSCs functions. In our previous study, we showed that Gal-1 was downregulated in aged BMSCs and global deletion of Gal-1 in mice caused bone loss via impaired osteogenesis potential of BMSCs. Gal-1 promoter is featured by CpG islands. However, there are no reports concerning the DNA methylation status in Gal-1 promoter during osteoporosis. In the current study, we sought to investigate the role of DNA methylation in Gal-1 downregulation in aged BMSCs. The potential for anti-bone loss therapy based on modulating DNA methylation is explored. Our results showed that Dnmt3b-mediated Gal-1 promoter DNA hypermethylation plays an important role in Gal-1 downregulation in aged BMSCs, which inhibited ß-catenin binding on Gal-1 promoter. Bone loss of aged mice was alleviated in response to in vivo deletion of Dnmt3b from BMSCs. Finally, when bone marrow of young wild-type (WT) mice or young Dnmt3bPrx1-Cre mice was transplanted into aged WT mice, Gal-1 level in serum and trabecular bone mass were elevated in recipient aged WT mice. Our study will benefit for deeper insights into the regulation mechanisms of Gal-1 expression in BMSCs during osteoporosis development, and for the discovery of new therapeutic targets for osteoporosis via modulating DNA methylation status.NEW & NOTEWORTHY There is Dnmt3b-mediated DNA methylation in Gal-1 promoter in aged bone marrow stromal cell (BMSC). DNA methylation causes Gal-1 downregulation and osteogenesis attenuation of aged BMSC. DNA methylation blocks ß-catenin binding on Gal-1 promoter. Bone loss of aged mice is alleviated by in vivo deletion of Dnmt3b from BMSC.


Asunto(s)
Benzamidas , Células Madre Mesenquimatosas , Osteoporosis , Tirosina/análogos & derivados , Animales , Ratones , Metilación de ADN/genética , beta Catenina/metabolismo , Galectina 1/genética , Galectina 1/metabolismo , Osteogénesis/genética , Osteoporosis/genética , Osteoporosis/metabolismo , Células Madre Mesenquimatosas/metabolismo , Regiones Promotoras Genéticas/genética , Diferenciación Celular , Células de la Médula Ósea/metabolismo
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA