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1.
Chem Soc Rev ; 53(13): 6694-6734, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38747082

RESUMEN

Delayed luminescence (DF), including phosphorescence and thermally activated delayed fluorescence (TADF), and circularly polarized luminescence (CPL) exhibit common and broad application prospects in optoelectronic displays, biological imaging, and encryption. Thus, the combination of delayed luminescence and circularly polarized luminescence is attracting increasing attention. The encapsulation of guest emitters in various host matrices to form host-guest systems has been demonstrated to be an appealing strategy to further enhance and/or modulate their delayed luminescence and circularly polarized luminescence. Compared with conventional liquid crystals, polymers, and supramolecular matrices, porous crystalline frameworks (PCFs) including metal-organic frameworks (MOFs), covalent-organic frameworks (COFs), zeolites and hydrogen-bonded organic frameworks (HOFs) can not only overcome shortcomings such as flexibility and disorder but also achieve the ordered encapsulation of guests and long-term stability of chiral structures, providing new promising host platforms for the development of DF and CPL. In this review, we provide a comprehensive and critical summary of the recent progress in host-guest photochemistry via the encapsulation engineering of guest emitters in PCFs, particularly focusing on delayed luminescence and circularly polarized luminescence. Initially, the general principle of phosphorescence, TADF and CPL, the combination of DF and CPL, and energy transfer processes between host and guests are introduced. Subsequently, we comprehensively discuss the critical factors affecting the encapsulation engineering of guest emitters in PCFs, such as pore structures, the confinement effect, charge and energy transfer between the host and guest, conformational dynamics, and aggregation model of guest emitters. Thereafter, we summarize the effective methods for the preparation of host-guest systems, especially single-crystal-to-single-crystal (SC-SC) transformation and epitaxial growth, which are distinct from conventional methods based on amorphous materials. Then, the recent advancements in host-guest systems based on PCFs for delayed luminescence and circularly polarized luminescence are highlighted. Finally, we present our personal insights into the challenges and future opportunities in this promising field.

2.
Acc Chem Res ; 56(16): 2225-2240, 2023 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-37535829

RESUMEN

ConspectusCO2 conversion to valuable chemicals is effective at reducing CO2 emissions. We previously proposed valorization strategies and developed efficient catalysts to address thermodynamic stability and kinetic inertness issues related to CO2 conversion. Earlier, we developed molecular capture reagents and catalysts to integrate CO2 capture and conversion, i.e., in situ transformation. Based on the mechanistic understanding of CO2 capture, activation, and transformation at a molecular level, we set out to develop heterogeneous catalysts by incorporating catalytic units into nanomaterials via the immobilization of active molecular catalysts onto nanomaterials and designing nanomaterials with intrinsic catalytic sites.In thermocatalytic CO2 conversion, carbonaceous and metal-organic framework (MOF)-based catalysts were developed for nonreductive and reductive CO2 conversion. Novel Cu- and Zn-based MOFs and carbon-supported Cu catalysts were prepared and successfully applied to the cycloaddition, carboxylation, and carboxylative cyclization reactions with CO2, generating cyclic carbonates, carboxyl acids, and oxazolidinones as respective target products. Reductive conversion of CO2, especially reductive functionalization with CO2, is a promising transformation strategy to produce valuable chemicals, alleviating chemical production that relies on petrochemistry. We explored the hierarchical reductive functionalization of CO2 using organocatalysts and proposed strategies to regulate the CO2 reduction level, triggering heterogeneous catalyst investigation. Introducing multiple active sites into nanomaterials opens possibilities to develop novel CO2 transformation strategies. CO2 capture and in situ conversion were realized with an N-doped carbon-supported Zn complex and MOF materials as CO2 adsorbents and catalysts. These nanomaterial-based catalysts feature high stability and excellent efficiency and act as shape-selective catalysts in some cases due to their unique pore structure.Nanomaterial-based catalysts are also appealing candidates for photocatalytic CO2 reduction (PCO2RR) and electrocatalytic CO2 reduction (ECO2RR), so we developed a series of hybrid photo-/electrocatalysts by incorporating active metal complexes into different matrixes such as porous organic polymers (POPs), metal-organic layers (MOLs), micelles, and conducting polymers. By introducing Re-bipyridine and Fe-porphyrin complexes into POPs and regulating the structure of the polymer chain, catalyst stability and efficiency increased in PCO2RR. PCO2RR in aqueous solution was realized by designing the Re-bipyridine-containing amphiphilic polymer to form micelles in aqueous solution and act as nanoreactors. We prepared MOLs with two different metallic centers, i.e., the Ni-bipyridine site and Ni-O node, to improve the efficiency for PCO2RR due to the synergistic effect of these metal centers. Sulfylphenoxy-decorated cobalt phthalocyanine (CoPc) cross-linked polypyrrole was prepared and used as a cathode, achieving the electrocatalytic transformation of diluted CO2 benefiting from the CO2 adsorption capability of polypyrrole. We fabricated immobilized 4-(t-butyl)-phenoxy cobalt phthalocyanine and Bi-MOF as cathodes to promote the paired electrolysis of CO2 and 5-hydroxymethylfurfural (HMF) and obtained CO2 reductive products and 2,5-furandicarboxylic acid (FDCA) efficiently.

3.
Fish Shellfish Immunol ; 146: 109382, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38242263

RESUMEN

The extensive application of Tetrabromobisphenol A (TBBPA) leads to the pollution of part of the water environment and brings great safety risks to aquatic animals. As a natural extract, tea polyphenols (TPs) have antioxidant and anti-inflammatory effects. Gills are one of the immune organs of fish and constitute the first line of defense of the immune system. However, it was unclear whether TPs could mitigate TBBPA-induced gills injury. Therefore, an animal model was established to investigate the effect of TPs on TBBPA-induced gills. The results indicated that TBBPA changed the coefficient and tissue morphology of carp gills. In addition, TBBPA induced oxidative stress and inflammation, leading to ferroptosis and apoptosis in carp gills. Dietary addition of TPs significantly improved the antioxidant capacity of carp, effectively inhibited the overexpression of TLR4/NF-κB and its mediated inflammatory response. Moreover, TPs restored iron metabolism, reduced the expression of pro-apoptotic factors thereby alleviating ferroptosis and apoptosis in carp gills. This study enriched the protective effect of TPs and provided a new way to improve the innate immunity of carp.


Asunto(s)
Carpas , Ferroptosis , Bifenilos Polibrominados , Animales , FN-kappa B/genética , FN-kappa B/metabolismo , Antioxidantes/metabolismo , Receptor Toll-Like 4/genética , Carpas/metabolismo , Branquias , Polifenoles/farmacología , Polifenoles/metabolismo , Transducción de Señal , Proteínas de Peces , Inflamación/inducido químicamente , Inflamación/veterinaria , Inflamación/metabolismo , Apoptosis , Té/metabolismo
4.
Angew Chem Int Ed Engl ; : e202408142, 2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38818643

RESUMEN

[FeFe] hydrogenases demonstrate remarkable catalytic efficiency in hydrogen evolution and oxidation processes. However, susceptibility of these enzymes to oxygen-induced degradation impedes their practical deployment in hydrogen-production devices and fuel cells. Recent investigations into the oxygen-stable (Hinact) state of the H-cluster revealed its inherent capacity to resist oxygen degradation. Herein, we present findings on Cl- and SH-bound [2Fe-2S] complexes, bearing relevance to the oxygen-stable state within a biological context. A characteristic attribute of these complexes is the terminal Cl-/SH- ligation to the iron center bearing the CO bridge. Structural analysis of the t-Cl demonstrates a striking resemblance to the Hinact state of DdHydAB and CbA5H. The t-Cl/t-SH exhibit reversible oxidation, with both redox species, electronically, being the first biomimetic analogs to the Htrans and Hinact states. These complexes exhibit notable resistance against oxygen-induced decomposition, supporting the potential oxygen-resistant nature of the Htrans and Hinact states. The swift reductive release of the Cl-/SH-group demonstrates its labile and kinetically controlled binding. The findings garnered from these investigations offer valuable insights into properties of the enzymatic O2-stable state, and key factors governing deactivation and reactivation conversion. This work contributes to the advancement of bio-inspired molecular catalysts and the integration of enzymes and artificial catalysts into H2-evolution devices and fuel-cell applications.

5.
Angew Chem Int Ed Engl ; : e202406552, 2024 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-38766881

RESUMEN

Triply interlocked [2]catenane complexes featuring two identical, mechanically interlocked units are extraordinarily rare chemical compounds, whose properties and applications remain open to detailed studies. Herein, we introduce the rational design of a new ligand precursor, L1, suitable for the synthesis of six triply interlocked [2]catenanes by coordination-driven self-assembly. The interlocked compounds can be reversibly converted into the corresponding simple triangular prism metallacage by addition of H2O or DMF solvents to their CH3OH solutions, thereby demonstrating the importance of π⋅⋅⋅π stacking and hydrogen bonding interactions in the formation of triply interlocked [2]catenanes. Moreover, extensive studies have been conducted to assess the remarkable photothermal conversion performance. Complex 6 a, exhibiting outstanding photothermal conversion performance (conversion efficiency in solution : 31.82 %), is used to prepare novel photoresponsive elastomer in combination with thermally activated liquid crystal elastomer. The resultant material displays robust response to near-infrared (NIR) laser and the capability of completely reforming the shape and reversible actuation, paving the way for the application of half-sandwich organometallic units in photo-responsive smart materials.

6.
Zhongguo Dang Dai Er Ke Za Zhi ; 26(6): 592-598, 2024 Jun 15.
Artículo en Zh | MEDLINE | ID: mdl-38926375

RESUMEN

OBJECTIVES: To investigate the value of single-phase gonadotropin releasing hormone (GnRH) stimulation test in the diagnosis of central precocious puberty (CPP) in girls with different levels of body mass index (BMI). METHODS: A retrospective analysis was performed for the data of 760 girls with breast development before 7.5 years of age who attended the Third Affiliated Hospital of Zhengzhou University from January 2017 to August 2023. According to the results of GnRH stimulation test and clinical manifestations, they were divided into a CPP group (297 girls) and a non-CPP group (463 girls). According to the values of BMI, the girls were divided into a normal weight group (540 girls), an overweight group (116 girls), and an obese group (104 girls). The receiver operating characteristic (ROC) curve was used to investigate the value of single-phase GnRH stimulation test in the diagnosis of CPP in girls with different levels of BMI. RESULTS: Luteinizing hormone (LH)/follicle-stimulating hormone at 30 minutes after GnRH stimulation had an area under the curve (AUC) of 0.985 in the diagnosis of CPP, which was higher than the AUC at 0, 60, and 90 minutes (P<0.05). LH at 30 minutes had a similar diagnostic value to LH at 60 minutes (P>0.05). LH at 30 minutes was negatively correlated with BMI and BMI-Z value (P<0.05).The AUC for diagnosing CPP in normal weight, overweight, and obese girls at 30 minutes LH was 0.952, 0.965, and 0.954, respectively (P<0.05). CONCLUSIONS: The 30-minute GnRH stimulation test has a good value in the diagnosis of CPP in girls with different levels of BMI and is expected to replace the traditional GnRH stimulation test, but the influence of BMI on LH level should be taken seriously.


Asunto(s)
Índice de Masa Corporal , Hormona Liberadora de Gonadotropina , Hormona Luteinizante , Pubertad Precoz , Humanos , Pubertad Precoz/diagnóstico , Pubertad Precoz/sangre , Femenino , Hormona Liberadora de Gonadotropina/sangre , Niño , Estudios Retrospectivos , Hormona Luteinizante/sangre , Hormona Folículo Estimulante/sangre , Curva ROC , Preescolar
7.
J Microsc ; 290(3): 153-160, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36916012

RESUMEN

In this paper, an optical waveguide evanescent field fluorescence microscopy is studied. Based on Maxwell's equation, a seven-layer theoretical analysis model is developed for the evaluation of an optical waveguide excitation fluorescence microscopy. The optical waveguide excitation fluorescence microscopy structure is systematically and comprehensively analysed at the wavelengths of 488, 532 and 646 nm for fluorescent dyes. The analysis results provide some useful suggestions, which will be beneficial to the research of an optical waveguide evanescent field fluorescence microscopy.

8.
J Org Chem ; 88(8): 4942-4964, 2023 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-36342846

RESUMEN

Carbon dioxide (CO2) is the major greenhouse gas and also an abundant and renewable carbon resource. Therefore, its chemical conversion and utilization are of great attraction for sustainable development. Especially, reductive conversion of CO2 with energy input has become a current hotspot due to its ability to access fuels and various important chemicals. Nowadays, the controllable CO2 hydrogenation to formic acid and alcohols using sustainable H2 resources has been regarded as an appealing solution to hydrogen storage and CO2 accumulation. In addition, photocatalytic CO2 reduction to CO also provides a potential way to utilize this greenhouse gas efficiently. Besides direct CO2 hydrogenation, CO2 reductive functionalization integrates CO2 reduction with subsequent C-X (X = N, S, C, O) bond formation and indirect transformation strategies, enlarging the diverse products derived from CO2 and promoting CO2 reductive conversion into a new stage. In this Perspective, the progress and challenges of CO2 reductive conversion, including hydrogenation, reductive functionalization, photocatalytic reduction, and photocatalytic reductive functionalization are summarized and discussed along with the key issues and future trends/directions in this field. We hope this Perspective can evoke intense interest and inspire much innovation in the promise of CO2 valorization.

9.
BMC Nephrol ; 24(1): 183, 2023 06 22.
Artículo en Inglés | MEDLINE | ID: mdl-37349681

RESUMEN

BACKGROUND: The phospholipase A2 receptor (PLA2R) associated with membranous nephropathy (MN) is an organ-specific autoimmune disease associated with PLA2R and human leukocyte antigen (HLA) genes. Familial PLA2R-related MN is rarely reported. The combination of anti-GBM disease and MN has been well documented, though the mechanism behind it remains unclear. CASE PRESENTATION: We describe two siblings diagnosed with pathology-confirmed PLA2R-related MN 1 year apart. And one of the two siblings developed an anti-GBM disease. The high-resolution HLA typing showed identical alleles in both siblings, specifically heterozygotes of DRB1*15:01/*03:01. CONCLUSION: We describe a familial case of PLA2R-related MN supporting the role of genetic factors that HLA-DRB1*15:01 and DRB1*03:01 predispose patients in the development of PLA2R-related MN in the Han Chinese population. The combination of MN and anti-GBM disease may also partially be associated with the same susceptible HLA allele DRB1*15:01.


Asunto(s)
Enfermedad por Anticuerpos Antimembrana Basal Glomerular , Glomerulonefritis Membranosa , Nefritis Hereditaria , Humanos , Glomerulonefritis Membranosa/complicaciones , Glomerulonefritis Membranosa/diagnóstico , Glomerulonefritis Membranosa/genética , Hermanos , Alelos , Nefritis Hereditaria/genética , Autoanticuerpos
10.
Nucleic Acids Res ; 49(20): 11596-11613, 2021 11 18.
Artículo en Inglés | MEDLINE | ID: mdl-34723322

RESUMEN

Using the programmable RNA-sequence binding domain of the Pumilio protein, we FLAG-tagged Xist (inactivated X chromosome specific transcript) in live mouse cells. Affinity pulldown coupled to mass spectrometry was employed to identify a list of 138 candidate Xist-binding proteins, from which, Ssb (also known as the lupus autoantigen La) was validated as a protein functionally critical for X chromosome inactivation (XCI). Extensive XCI defects were detected in Ssb knockdown cells, including chromatin compaction, death of female mouse embryonic stem cells during in vitro differentiation and chromosome-wide monoallelic gene expression pattern. Live-cell imaging of Xist RNA reveals the defining XCI defect: Xist cloud formation. Ssb is a ubiquitous and versatile RNA-binding protein with RNA chaperone and RNA helicase activities. Functional dissection of Ssb shows that the RNA chaperone domain plays critical roles in XCI. In Ssb knockdown cells, Xist transcripts are unstable and misfolded. These results show that Ssb is critically involved in XCI, possibly as a protein regulating the in-cell structure of Xist.


Asunto(s)
Pliegue del ARN , ARN Largo no Codificante/química , Proteínas de Unión al ARN/metabolismo , Inactivación del Cromosoma X , Animales , Autoantígenos/química , Autoantígenos/metabolismo , Sitios de Unión , Línea Celular , Ratones , Unión Proteica , ARN Largo no Codificante/metabolismo , Proteínas de Unión al ARN/química , Proteínas de Unión al ARN/genética
11.
Mediators Inflamm ; 2023: 2613766, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37035758

RESUMEN

Objective: To explore the relationship between circulating IGFBP-3, IL-6, and bone mineral density and the potential diagnostic role of circulating IGFBP-3 and IL-6 in postmenopausal women with osteoporosis. Methods: Eighty-five postmenopausal women at Soochow University's First Affiliated Hospital, Osteoporosis and Menopause Clinics, were recruited. Forty-five of 85 women were diagnosed with osteoporosis. Circulating IL-6, PTH, 1,25(OH)2D3, osteocalcin (OST), IGF-1, IGFBP-3, and bone mineral density (BMD) of the lumbar spine (LS) and femoral neck (FN) were measured in 40 ordinary and 45 osteoporotic women. A simple regression analysis calculated the correlation between age, BMD, IL-6, and IGFBP-3. Multiple stepwise regression analyses were conducted to determine which variables were independently related to BMD. The potential role of IGFBP-3 and IL-6 in the diagnosis of postmenopausal osteoporosis was predicted using the area under the receiver operating characteristic curve (ROC, AUC). Results: Age, years since menopause, and circulating IL-6, PTH, and IGFBP-3 were significantly higher in the osteoporosis group compared to the normal group. Osteoporotic women had substantially lower BMDs of the LS and FN than normal women. Age-related increases were found for IGFBP-3 and IL-6, whereas age-related decreases were observed for LS/FN BMD. IGFBP-3 and IL-6 were both negatively correlated with LS and FN BMD. Stepwise multiple regression analysis showed that IGFBP-3 and IL-6 were strong predictors of BMD in postmenopausal women. AUC cut-off values (IGFBP-3: 3.65, IL-6: 0.205) were best evaluated for the diagnosis of postmenopausal women with osteoporosis, and the AUC for circulating IGFBP-3 and IL-6 were 0.706 (95% CI 0.594-0.818) and 0.685 (95% CI 0.571-0.798), respectively. Conclusion: In this cross-sectional study of postmenopausal women, IGFBP-3 and IL-6 were negatively related to BMD. Circulating IGFBP-3 and IL-6 might be essential predictors of postmenopausal osteoporosis and can help predict osteoporotic fracture.


Asunto(s)
Osteoporosis Posmenopáusica , Osteoporosis , Femenino , Humanos , Interleucina-6 , Estudios Transversales , Posmenopausia , Proteína 3 de Unión a Factor de Crecimiento Similar a la Insulina , Densidad Ósea , Vértebras Lumbares , Absorciometría de Fotón
12.
Chem Biodivers ; 20(4): e202300214, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36896990

RESUMEN

A new cembranolide, namely, sinupendunculide A (1), along with eight known related compounds (2-9), was isolated from the South China Sea Soft coral Sinularia pendunculata. The structure of sinupendunculide A (1) was established by extensive spectroscopic analysis and X-ray diffraction experiments. In a bioassay, anti-colorectal cancer (CRC) activity was performed, and the results showed that several compounds exhibited cytotoxicity against RKO cells, and a preliminary structure-activity relationship was analysed. Meanwhile, the most effective compound 7 was proven to increase reactive oxygen species levels, which promoted cell apoptosis and inhibited cell proliferation.


Asunto(s)
Antozoos , Antineoplásicos , Diterpenos , Neoplasias , Animales , Antozoos/química , China , Diterpenos/farmacología , Diterpenos/química , Estructura Molecular , Antineoplásicos/química , Antineoplásicos/farmacología , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/prevención & control
13.
Molecules ; 28(2)2023 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-36677579

RESUMEN

It is both important and required to quickly and accurately detect chemical warfare agents, such as the highly toxic nerve agent sarin. Surface-enhanced Raman scattering (SERS) has received considerable attention due to its rapid results, high sensitivity, non-destructive data acquisition, and unique spectroscopic fingerprint. In this work, we successfully prepared SERS cotton swabs (CSs) for the detection of the sarin simulant agent dimethyl methyl phosphonate (DMMP) by anchoring N1-(3-trimethoxysilylpropyl) diethylenetriamine (ATS)/silver nanoparticle (AgNP) nanocomposites on CSs using ATS as the stabilizer and coupling agent. Simultaneously, the binding mode and reaction mechanics between the AgNP, ATS, and CS were confirmed by XPS. The modified CSs exhibited good uniformity, stability, and adsorption capability for SERS measurements, enabling the adsorption and detection of DMMP residue from an irregular surface via a simple swabbing process, with a detection limit of 1 g/L. The relative standard deviations (RSDs) of RSD710 = 5.6% had high reproducibility. In this research, the fabrication method could easily be extended to other cellulose compounds, such as natural fibers and paper. Furthermore, the versatile SERS CSs can be used for the on-site detection of DMMP, particularly in civil and defense applications, to guarantee food security and the health of the population.

14.
J Sci Food Agric ; 103(10): 5126-5137, 2023 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-37005496

RESUMEN

BACKGROUND: Fragrant rice is increasingly popular with the public owing to its fresh aroma, and 2-acetyl-1-pyrroline (2-AP) is the main characteristic component of the aroma in fragrant rice. Rice-fish co-culture is an environmentally friendly practice in sustainable agriculture. However, the effect of rice-fish co-culture on 2-AP in grains has received little study. A conventional fragrant rice (Meixiangzhan 2) was used, and a related field experiment during three rice growing seasons was conducted to investigate the effects of rice-fish co-culture on 2-AP, as well as the rice quality, yield, plant nutrients, and precursors and enzyme activities of 2-AP biosynthesis in leaves. This study involved three fish stocking density treatments (i.e. 9000 (D1), 15 000 (D2), and 21 000 (D3) fish fries per hectare) and rice monocropping. RESULTS: Rice-fish co-culture increased the 2-AP content in grains by 2.5-49.4% over that of the monocropping, with significant increases in the early and late rice seasons of 2020. Rice-fish co-culture treatments significantly promoted seed-setting rates by 3.39-7.65%, and improved leaf nutrients and rice quality. Notably, the D2 treatment significantly increased leaf total nitrogen (TN), total phosphorus (TP), and total potassium (TK) contents and the head rice rate at maturity stage, while significantly decreased chalkiness degree. There was no significant difference in rice yield. CONCLUSION: Rice-fish co-culture had positive effects on 2-AP synthesis, rice quality, seed-setting rates, and plant nutrient contents. The better stocking density of field fish for rice-fish co-culture in this study was 15 000 fish ha-1 . © 2023 Society of Chemical Industry.


Asunto(s)
Oryza , Animales , Oryza/química , Grano Comestible , Semillas , Pirroles
15.
Zhongguo Zhong Yao Za Zhi ; 48(7): 1815-1823, 2023 Apr.
Artículo en Zh | MEDLINE | ID: mdl-37282956

RESUMEN

It is generally believed that high-quality Bupleurum scorzonerifolium roots possess specific morphological characteristics, being red, robust, and long with strong odor. However, the scientific connotation of these characteristics has not been elucidated. According to the theory of "quality evaluation through morphological identification", we studied the correlations between appearance traits(the RGB value of root surface, root length, root diameter, dry weight, and ratio of phloem to xylem) and content of main chemical components(volatile oils, total saponins, total flavonoids, total polysaccharides, and seven saikosaponins) of B. scorzonerifolium roots. Epson Scanner and ImageJ were used to scan the root samples and measure the appearance traits. Ultraviolet spectrophotometry and HPLC were employed to determine the content of chemical components. The correlation, regression, and cluster analyses were performed to study the correlations between the appearance traits and the content of chemical components. The results showed that the content of volatile oils and saikosaponins were significantly correlated with RGB value, root length, and root diameter, indicating that within a certain range, the roots being redder, longer, and thicker had higher content of volatile oils and saikosaponins. According to the appearance traits and chemical component content, the 14 samples from different producing areas were classified into four grades, and the differences in morphological traits and chemical component content were consistent among different grades. The findings in this study demonstrate that appearance traits(RGB value, root length, and root diameter) can be used to evaluate the quality of B. scorzonerifolium roots. Meanwhile, this study lays a foundation for establishing an objective quality evaluation method for B. scorzonerifolium roots.


Asunto(s)
Bupleurum , Aceites Volátiles , Ácido Oleanólico , Saponinas , Bupleurum/química , Saponinas/análisis , Ácido Oleanólico/análisis , Aceites Volátiles/análisis , Raíces de Plantas/química
16.
J Neurochem ; 162(3): 290-304, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35598091

RESUMEN

Alzheimer's disease (AD) remains a leading cause of dementia and no therapy that reverses underlying neurodegeneration is available. Recent studies suggest the protective role of artemisinin, an antimalarial drug, in neurological disorders. In this study, we investigated the therapeutic potential of artesunate, a water-soluble derivative of artemisinin, on amyloid-beta (Aß)-treated challenged microglial BV-2, neuronal N2a cells, and the amyloid precursor protein/presenilin (APP/PS1) mice model. We found that Aß significantly induced multiple AD-related phenotypes, including increased expression/production of pro-inflammatory cytokines from microglial cells, enhanced cellular and mitochondrial production of reactive oxygen species, promoted mitochondrial fission, inhibited mitochondrial fusion, suppressed mitophagy or biogenesis in both cell types, stimulated apoptosis of neuronal cells, and microglia-induced killing of neurons. All these in vitro phenotypes were attenuated by artesunate. In addition, the over-expression of the mitochondrial fission protein Drp-1, or down-regulation of the mitochondrial fusion protein OPA-1 both reduced the therapeutic benefits of artesunate. Artesunate also alleviated AD phenotypes in APP/PS1 mice, reducing Aß deposition, and reversing deficits in memory and learning. Artesunate protects neuronal and microglial cells from AD pathology, both in vitro and in vivo. Maintaining mitochondrial dynamics and simultaneously targeting multiple AD pathogenic mechanisms are associated with the protective effects of artesunate. Consequently, artesunate may become a promising therapeutic for AD.


Asunto(s)
Enfermedad de Alzheimer , Enfermedad de Alzheimer/metabolismo , Péptidos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Animales , Artesunato/metabolismo , Artesunato/farmacología , Artesunato/uso terapéutico , Modelos Animales de Enfermedad , Ratones , Ratones Transgénicos , Dinámicas Mitocondriales , Proteínas Mitocondriales/metabolismo , Neuronas/metabolismo , Presenilina-1/genética
17.
Neurobiol Dis ; 171: 105802, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35753626

RESUMEN

ß-thalassemia is associated with multiple hematological and cerebrovascular symptoms linked to a hypercoagulable state that has not been fully replicated in animal models for the development of stroke treatments. Herein we compared the physiological properties and responses to transient cerebral hypoxia-ischemia (tHI) between six-month-old wildtype and heterozygous Th3/+ mice, a model of non-transfusion-dependent ß-thalassemia intermedia (ß-TI). We found that Th3/+ mice developed microcytic anemia, splenomegaly, higher platelet counts, and increased platelet-erythrocyte plus erythrocyte-leukocyte aggregates. Furthermore, Th3/+ mice showed diminished cerebrovascular reactivity (CVR) and cortical oxygen saturation under repetitive hypercapnic challenges. When subjected to a sub-threshold tHI insult, platelets and leukocytes in Th3/+ mice adhered to the cerebrovascular wall or formed aggregates, while their counterparts flew through smoothly in wildtype mice. Subsequently, Th3/+ mice showed increased fibrin deposition around cerebral blood vessels and larger infarction than wildtype mice, especially in female Th3/+ mice. Collectively these results showed that Th3/+ mice mimic key clinical features and a propensity to thromboembolism in ß-TI patients. The hypercoagulable state in Th3/+ mice is likely caused by multiple hematological and CVR anomalies that are similar, but are not identical to those in the mouse model of sickle cell anemia. As such, we suggest that Th3/+ mice are a useful model to study the pathological mechanisms and prophylactic stroke treatments in thalassemia patients.


Asunto(s)
Hipoxia-Isquemia Encefálica , Accidente Cerebrovascular , Talasemia beta , Animales , Modelos Animales de Enfermedad , Femenino , Hipoxia-Isquemia Encefálica/complicaciones , Ratones , Accidente Cerebrovascular/complicaciones , Talasemia beta/complicaciones , Talasemia beta/patología
18.
J Org Chem ; 87(5): 2711-2720, 2022 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-35018783

RESUMEN

An efficient annulation method for the synthesis of polysubstituted dihydrofurans from 1,3-dicarbonyl compounds and maleimides is described. The reactions can afford furo[2,3-c]pyrrole derivatives with satisfactory yields. The developed strategy realizes the direct oxidative double C(sp3)-H functionalization in the presence of copper(I) salts and 2-(tert-butylperoxy)-2-methylpropane. Meanwhile, this protocol features a mild reaction condition and simple catalytic system. A reaction mechanism involving a single electron oxidation is also proposed.

19.
Inorg Chem ; 61(3): 1636-1643, 2022 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-34995446

RESUMEN

Two Cd-based supramolecular coordination polymers, [Cd3(CzIP)3(DMF)2] (1) and [Cd2(CzIP)2(DMF)4] (2), were synthesized by using 5-(carbazol-9-yl) isophthalate (CzIP) as ligands. These two compounds exhibit multiple luminescence emissions; apart from fluorescence, time- and temperature-dependent ultralong phosphorescence (RTP) were also achieved under room conditions. Significantly, compound 1 has a long-lived afterglow of 0.93 s at 545 nm under ambient conditions. Compound 2 shows nearly pure white-light emission with CIE coordinates of (0.33, 0.33) via the dual emission of fluorescence and phosphorescence. It has come to our attention that it is the first example of a luminescent coordination polymer with single-phase white-light emission and color-evolution RTP. In addition, the long-lived RTP materials can be used in time-dependent anticounterfeiting and white-light-emitting diodes. Experimental and singlet and triplet state calculations indicate that both C-H···π interaction and inter- and intramolecular charge transfer interactions could be beneficial to the emission of ultralong RTP.

20.
Org Biomol Chem ; 20(17): 3506-3510, 2022 05 04.
Artículo en Inglés | MEDLINE | ID: mdl-35420611

RESUMEN

A copper-catalyzed cascade reaction of α-diazocarbonyl compounds with ethenesulfonyl fluoride (ESF) is developed, affording a variety of highly functionalized pyrazolyl aliphatic sulfonyl fluorides in good to excellent yields (66-98%). This transformation features broad substrates, exclusive regioselectivity, high atom economy and operational simplicity, thus providing a straightforward method for the direct construction of pyrazole-containing aliphatic sulfonyl fluorides, which will provide great applicable value in medicinal chemistry and other related disciplines.


Asunto(s)
Fluoruros , Ácidos Sulfínicos , Química Farmacéutica , Fluoruros/química , Pirazoles , Ácidos Sulfínicos/química
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