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1.
Arch Gerontol Geriatr ; 128: 105596, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39232423

RESUMO

BACKGROUND: Sarcopenia, characterized by age-related loss of muscle mass and function, poses a significant public health concern, particularly in Asia's rapidly aging population. This systematic review and meta-analysis aimed to evaluate the current epidemiology of sarcopenia in Asia using the 2019 Asian Working Group for Sarcopenia (AWGS) diagnostic criteria. METHODS: Databases including PubMed, Embase, Web of Science, and Cochrane were systematically searched for studies published until December 7, 2023, involving older adults aged ≥ 60 years diagnosed with sarcopenia using the 2019 AWGS criteria in Asia. Study quality was assessed, and meta-analyses were conducted to estimate the pooled prevalence of sarcopenia, possible sarcopenia, and severe sarcopenia. RESULTS: A total of 140 studies, collectively involving 156,325 participants (67.1 % community-dwelling older adults with the minimum age for participant inclusion ranging from 60 to 80 years) from various Asian countries, were included. The overall prevalence of sarcopenia among community-dwelling older adults was 16.5 % (95 % CI: 14.7 %-18.4 %). Notably, the prevalence of possible sarcopenia was higher at 28.7 % (95 % CI: 22.0 %-36.5 %), while severe sarcopenia had a lower prevalence of 4.4 % (95 % CI: 3.3 %-5.8 %). Subgroup analyses revealed variations in sarcopenia prevalence based on diagnostic modalities, ranging from 7.5 % (95 % CI: 6.0 %-9.4 %) for assessments using bioelectrical impedance analysis, handgrip strength, gait speed, chair stand and short physical performance battery, to 20.8 % (95 % CI: 18.9 %-23.0 %) when using dual-energy X-ray absorptiometry coupled with muscle strength and physical performance measures. CONCLUSION: This comprehensive systematic review and meta-analysis highlights the substantial burden of sarcopenia among older adults in Asia, underscoring the need for early identification and intervention strategies to mitigate its adverse consequences on public health.

2.
Inorg Chem ; 63(35): 16284-16292, 2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-39152397

RESUMO

Multicolor-tunable room-temperature phosphorescence (RTP) is attracting wide attention in optoelectronic applications. Here, we propose a coordination-oriented assembly approach to achieve wide-range RTP with a benzimidazole derivative (2,7-diazabenzimidazole, DZBIM) as a luminogen. These two compounds exhibit unexpected excitation-responsive RTP emission, and the phosphorescence emission nearly covers the entire visible region with the change of the excitation wavelength from 360 to 620 nm. To the best of our knowledge, this is the first report of coordination polymers with such a full-color-tunable RTP. Compound 1 also shows white-light emission upon excitation at 280 nm. Experimental and theoretical results demonstrate that multiple intermolecular interactions and emission centers from different aggregates are responsible for the generation of multicolor emission. The white-light emission and multiple anticounterfeiting are explored. Besides, compound 1 exhibits high antibacterial activity benefiting from efficient 1O2 generation. This work provides an efficient way to prepare a color-tunable RTP.

3.
Parasite ; 31: 48, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39140873

RESUMO

Species of the genus Rhabdias Stiles & Hassall, 1905 are common parasitic nematodes occurring in the lungs of amphibians and reptiles worldwide. In the present study, Rhabdias macrocephalum n. sp. is described using integrated morphological methods (light and scanning electron microscopy) and molecular approaches (sequencing of the nuclear 28S and ITS regions, and mitochondrial cox1, cox2, and 12S genes) based on specimens collected from the green striped tree dragon Diploderma splendidum (Barbour & Dunn) (Reptilia: Agamidae) in China. The complete mitochondrial genome of R. macrocephalum n. sp. was sequenced and annotated: it is 14,819 bp in length, including 12 protein coding genes (missing atp8), 22 tRNA genes, 2 rRNA genes and three non-coding regions. The gene arrangement of R. macrocephalum n. sp. is different from all of the currently available mitogenomes of nematodes and represents a novel type of mitochondrial gene arrangement reported in Nematoda. Molecular phylogenetic results based on the ITS + 28S data support the monophyly of Entomelas, Pneumonema, Serpentirhabdias, and Rhabdias, and showed R. macrocephalum n. sp. forming a most basal lineage in Rhabdias.


Title: Morphologie, génome mitochondrial complet et phylogénie moléculaire de Rhabdias macrocephalum n. sp. (Nematoda : Rhabdiasidae) de Diploderma splendidum (Reptilia : Agamidae). Abstract: Les espèces du genre Rhabdias Stiles & Hassall, 1905 sont des nématodes parasites courants présents dans les poumons des amphibiens et des reptiles du monde entier. Dans cette étude, Rhabdias macrocephalum n. sp. est décrit à l'aide de méthodes morphologiques intégrées (microscopie optique et électronique à balayage) et d'approches moléculaires (séquençage des régions nucléaires 28S et ITS et des gènes mitochondriaux cox1, cox2 et 12S) basées sur des spécimens collectés chez le lézard Diploderma splendidum (Barbour & Dunn) (Reptilia : Agamidae) de Chine. Le génome mitochondrial complet de R. macrocephalum n. sp. a été séquencé et annoté : il a une longueur de 14 819 pb, dont 12 gènes codants pour des protéines (atp8 manquant), 22 gènes d'ARNt, 2 gènes d'ARNr et trois régions non codantes. L'arrangement génétique de R. macrocephalum n. sp. est différent de tous les mitogénomes de nématodes actuellement disponibles et représente un nouveau type d'arrangement de gènes mitochondriaux signalé chez les nématodes. Les résultats phylogénétiques moléculaires basés sur les données ITS + 28S ont soutenu la monophylie d'Entomelas, Pneumonema, Serpentirhabdias et Rhabdias, et ont montré que R. macrocephalum n. sp. forme la lignée la plus basale chez Rhabdias.


Assuntos
Genoma Mitocondrial , Lagartos , Filogenia , Animais , China , Lagartos/parasitologia , Rhabditoidea/genética , Rhabditoidea/classificação , Rhabditoidea/anatomia & histologia , Rhabditoidea/ultraestrutura , Masculino , Feminino , Infecções por Rhabditida/parasitologia , Infecções por Rhabditida/veterinária , Microscopia Eletrônica de Varredura/veterinária
4.
Chem Commun (Camb) ; 60(74): 10212-10215, 2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39206734

RESUMO

Herein, chiral metal-organic frameworks (MOFs), DCF-20 and LCF-20, were utilized as matrices for both chirality transfer and energy transfer. HBT1@MOFs and HBT2@MOFs emit excitation-dependent circularly polarized luminescence (CPL) due to excited-state intramolecular proton transfer (ESIPT). HBT1/C152/NIR@MOFs exhibit full-color and white CPL. The luminescence dissymmetry factors (glum) were significantly increased, benefiting from the efficient chirality space transfer and high luminescence efficiency.

6.
Zool Res ; 45(5): 983-989, 2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39085754

RESUMO

Most described Mesozoic ants belong to stem groups that existed only during the Cretaceous period. Previously, the earliest known crown ants were dated to the Turonian (Late Cretaceous, ca. 94-90 million years ago (Ma)) deposits found in the USA, Kazakhstan, and Botswana. However, the recent discovery of an alate male ant in Kachin amber from the earliest Cenomanian (ca. 99 Ma), representing a new genus and species, Antiquiformica alata, revises the narrative on ant diversification. Antiquiformica can be distinctly differentiated from all known male stem ants by its geniculate antennae with elongated scape, extending far beyond the occipital margin of the head and half the length of the funiculus, as well as its partly reduced forewing venation. Furthermore, the combination of a one-segmented waist with a well-developed node, elongated scape extending beyond the occipital margin, and reduced forewing venation, particularly the completely reduced m-cu and rs-m crossveins and absence of rm and mcu closed cells, firmly places the fossil within the extant subfamily Formicinae. Fourier transform infrared spectroscopy (FTIR) confirmed that the amber containing Antiquiformica alata originated from the Kachin mines in Myanmar. This discovery significantly revises our understanding of the early evolution of Formicinae. The presence of Antiquiformica in Cenomanian amber indicates that the subfamily Formicinae emerged at least by the start of the Late Cretaceous, with crown ants likely originating earlier during the earliest Cretaceous or possibly the Late Jurassic, although paleontological evidence is lacking to support the latter hypothesis.


Assuntos
Formigas , Evolução Biológica , Fósseis , Animais , Formigas/anatomia & histologia , Formigas/classificação , Formigas/fisiologia , Fósseis/anatomia & histologia , Masculino , Âmbar , Filogenia
7.
World J Psychiatry ; 14(7): 1027-1033, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39050209

RESUMO

BACKGROUND: Delirium is a neuropsychiatric syndrome characterized by acute disturbances of consciousness with rapid onset, rapid progression, obvious fluctuations, and preventable, reversible, and other characteristics. Patients with delirium in the intensive care unit (ICU) are often missed or misdiagnosed and do not receive adequate attention. AIM: To analyze the risk factors for delirium in ICU patients and explore the application of emotional nursing with pain nursing in the management of delirium. METHODS: General data of 301 critically ill patients were retrospectively collected, including histories (cardiovascular and cerebrovascular diseases, hypertension, smoking, alcoholism, and diabetes), age, sex, diagnosis, whether surgery was performed, and patient origin (emergency/clinic). Additionally, the duration of sedation, Richmond Agitation Sedation Scale score, combined emotional and pain care, ventilator use duration, vasoactive drug use, drainage tube retention, ICU stay duration, C-reactive protein, procalcitonin, white blood cell count, body temperature, Acute Physiology and Chronic Health Evaluation II (APACHE II) score, and Sequential Organ Failure Assessment score were recorded within 24 h after ICU admission. Patients were assessed for delirium according to confusion assessment method for the ICU, and univariate and multivariate logistic regression analyses were performed to identify the risk factors for delirium in the patients. RESULTS: Univariate logistic regression analysis was performed on the 24 potential risk factors associated with delirium in ICU patients. The results showed that 16 risk factors were closely related to delirium, including combined emotional and pain care, history of diabetes, and patient origin. Multivariate logistic regression analysis revealed that no combined emotional and pain care, history of diabetes, emergency source, surgery, long stay in the ICU, smoking history, and high APACHE II score were independent risk factors for delirium in ICU patients. CONCLUSION: Patients with diabetes and/or smoking history, postoperative patients, patients with a high APACHE II score, and those with emergency ICU admission need emotional and pain care, flexible visiting modes, and early intervention to reduce delirium incidence.

8.
Zhongguo Dang Dai Er Ke Za Zhi ; 26(6): 592-598, 2024 Jun 15.
Artigo em Chinês | MEDLINE | ID: mdl-38926375

RESUMO

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.


Assuntos
Índice de Massa Corporal , Hormônio Liberador de Gonadotropina , Hormônio Luteinizante , Puberdade Precoce , Humanos , Puberdade Precoce/diagnóstico , Puberdade Precoce/sangue , Feminino , Hormônio Liberador de Gonadotropina/sangue , Criança , Estudos Retrospectivos , Hormônio Luteinizante/sangue , Hormônio Foliculoestimulante/sangue , Curva ROC , Pré-Escolar
9.
Anal Methods ; 16(24): 3831-3838, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38828794

RESUMO

We designed and prepared probe W-1 for the detection of H2O2. W-1 showed excellent selectivity for H2O2 and was accompanied by colorimetric signal changes. The excellent linear relationship between fluorescence intensity and H2O2 concentration (0-100 µM) provided favorable conditions for its quantitative detection. In addition, the combination of portable test strips with a smartphone platform provided great convenience for on-site visual detection of H2O2. Moreover, W-1 possessed targeting mitochondria property and could be applied to image the exogenous and endogenous H2O2 in cells to distinguish normal cells and cancer cells. Lastly, W-1 was used for monitoring the H2O2 fluctuation of the diabetic process in mice, and the results showed an increase in H2O2 levels in diabetes. Therefore, the probe provided a tool for understanding the pathological and physiological mechanisms of diabetes by imaging H2O2.


Assuntos
Diabetes Mellitus Experimental , Corantes Fluorescentes , Peróxido de Hidrogênio , Mitocôndrias , Peróxido de Hidrogênio/metabolismo , Animais , Mitocôndrias/metabolismo , Corantes Fluorescentes/química , Camundongos , Humanos , Colorimetria/métodos , Imagem Óptica/métodos
10.
Angew Chem Int Ed Engl ; 63(32): e202406552, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-38766881

RESUMO

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.

11.
Chem Soc Rev ; 53(13): 6694-6734, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38747082

RESUMO

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.

12.
ChemSusChem ; 17(16): e202400608, 2024 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-38747335

RESUMO

A Cu/Co tandem catalysis protocol was developed to conduct the hydroformylation of olefins using CO2/H2 and PMHS (polymethylhydrosiloxane) as a readily available and environmentally friendly hydride source. This methodology was performed via a two-step approach consisting of the copper-catalyzed reduction of CO2 by hydrosilane and subsequent cobalt-promoted hydroformylation with H2 and the in situ formed CO. The optimized triphos oxide ligand, which presumably facilitates the migratory insertion of CO gives moderate to excellent yields for both terminal and internal alkenes. This earth-abundant metal catalysis provides a reliable and efficient way to afford useful aldehydes in industry using silicon by-product PMHS as hydrogen source and renewable CO2 as carbonyl source.

13.
Angew Chem Int Ed Engl ; 63(33): e202408142, 2024 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-38818643

RESUMO

[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.

14.
Chem Commun (Camb) ; 60(48): 6182-6185, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38804974

RESUMO

Two pairs of chiral MOFs with hierarchical chiral structures were constructed through assembly of achiral AIE-type multidentate linkers and chiral camphoric acid. Non-reciprocal circularly polarized luminescence (CPL) can be observed on the macroscopic due to the coexistence of optical anisotropic and chiroptical nature. This study provides a new perspective to recognize and construct chiral crystalline materials.

15.
Org Lett ; 26(15): 3241-3246, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38578088

RESUMO

Herein, we report an electrochemical protocol for the dicarboxylation of aryl alkynes using CO2. With a graphite rod as the cathode and Al as the sacrificial anode, a series of valuable butenedioic acids are obtained in moderate to excellent yields with an E/Z ratio up to 50:1. This method features high E-selectivity, high step and atom economy, easy scalability, and a nice substrate scope, which renders it appealing for promising applications in organic synthesis and materials chemistry.

16.
Cell Rep Med ; 5(4): 101483, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38579727

RESUMO

Immune cell phenotyping frequently detects lineage-unrelated receptors. Here, we report that surface receptors can be transferred from primary macrophages to CD4 T cells and identify the Fcγ receptor CD32 as driver and cargo of this trogocytotic transfer. Filamentous CD32+ nanoprotrusions deposit distinct plasma membrane patches onto target T cells. Transferred receptors confer cell migration and adhesion properties, and macrophage-derived membrane patches render resting CD4 T cells susceptible to infection by serving as hotspots for HIV-1 binding. Antibodies that recognize T cell epitopes enhance CD32-mediated trogocytosis. Such autoreactive anti-HIV-1 envelope antibodies can be found in the blood of HIV-1 patients and, consistently, the percentage of CD32+ CD4 T cells is increased in their blood. This CD32-mediated, antigen-independent cell communication mode transiently expands the receptor repertoire and functionality of immune cells. HIV-1 hijacks this mechanism by triggering the generation of trogocytosis-promoting autoantibodies to gain access to immune cells critical to its persistence.


Assuntos
Infecções por HIV , Soropositividade para HIV , HIV-1 , Humanos , Linfócitos T CD4-Positivos , Receptores de IgG/metabolismo , Autoanticorpos/metabolismo , Trogocitose
17.
Foods ; 13(6)2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38540809

RESUMO

The nonantimicrobial properties and relatively poor mechanical properties of hydroxyethyl cellulose (HEC) limit its use in packaging. Sulfated rice bran polysaccharides (SRBP) possess significant antioxidant and antimicrobial activities. The purpose of this study was to investigate the effect of different concentrations of SRBP on the physical and mechanical properties and the functional characteristics of HEC/SRBP films. The physical properties of the HEC/20% SRBP films, such as water resistance, water vapor barrier, light barrier, and tensile strength, improved significantly (p < 0.05) compared with those of the HEC films. Scanning electron microscopy and Fourier transform infrared spectrometry showed that HEC formed hydrogen bonds with SRBP and exhibited better compatibility. Thermogravimetric analysis revealed that the addition of SRBP was beneficial to the thermal stability of the films. In addition, the antioxidant and bacteriostatic properties of the films were enhanced by the addition of SRBP to HEC, with the 20% SRBP films showing the most significant enhancement in activity. Therefore, the HEC/20% SRBP films show potential for development for use as active food packaging.

18.
Fitoterapia ; 175: 105924, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38537886

RESUMO

Alzheimer's disease (AD) is a progressive neurodegenerative disease, and accumulating evidence suggested that proteostatic imbalance is a key feature of the disease. Traditional Chinese medicine exhibits a multi-target therapeutic effect, making it highly suitable for addressing protein homeostasis imbalance in AD. Dendrobium officinale is a traditional Chinese herbs commonly used as tonic agent in China. In this study, we investigated protection effects of D. officinale phenolic extract (SH-F) and examined its underlying mechanisms by using transgenic Caenorhabditis elegans models. We found that treatment with SH-F (50 µg/mL) alleviated Aß and tau protein toxicity in worms, and also reduced aggregation of polyglutamine proteins to help maintain proteostasis. RNA sequencing results showed that SH-F treatment significantly affected the proteolytic process and autophagy-lysosomal pathway. Furthermore, we confirmed that SH-F showing maintainance of proteostasis was dependent on bec-1 by qRT-PCR analysis and RNAi methods. Finally, we identified active components of SH-F by LC-MS method, and found the five major compounds including koaburaside, tyramine dihydroferulate, N-p-trans-coumaroyltyramine, naringenin and isolariciresinol are the main bioactive components responsible for the anti-AD activity of SH-F. Our findings provide new insights to develop a treatment strategy for AD by targeting proteostasis, and SH-F could be an alternative drug for the treatment of AD.


Assuntos
Doença de Alzheimer , Peptídeos beta-Amiloides , Autofagia , Caenorhabditis elegans , Dendrobium , Modelos Animais de Doenças , Extratos Vegetais , Proteostase , Animais , Caenorhabditis elegans/efeitos dos fármacos , Doença de Alzheimer/tratamento farmacológico , Dendrobium/química , Proteostase/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Peptídeos beta-Amiloides/metabolismo , Extratos Vegetais/farmacologia , Animais Geneticamente Modificados , Proteínas tau/metabolismo , Fenóis/farmacologia , Fenóis/isolamento & purificação , Flavanonas/farmacologia , Medicamentos de Ervas Chinesas/farmacologia , Compostos Fitoquímicos/farmacologia , Compostos Fitoquímicos/isolamento & purificação
19.
ChemSusChem ; 17(14): e202400090, 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-38426643

RESUMO

Designing earth-abundant metal complexes as efficient molecular photocatalysts for visible light-driven CO2 reduction is a key challenge in artificial photosynthesis. Here, we demonstrated the first example of a mononuclear iron pyridine-thiolate complex that functions both as a photosensitizer and catalyst for CO2 reduction. This single-component bifunctional molecular photocatalyst efficiently reduced CO2 to formate and CO with a total turnover number (TON) of 46 and turnover frequency (TOF) of 11.5 h-1 in 4 h under visible light irradiation. Notably, the quantum yield was determined to be 8.4 % for the generation of formate and CO at 400 nm. Quenching experiments indicate that high photocatalytic activity is mainly attributed to the rapid intramolecular quenching protocol. The mechanism investigation by DFT calculation and electrochemical studies revealed that the protonation of Febpy(pyS)2 is indispensable step for photocatalytic CO2 reduction.

20.
Chempluschem ; 89(7): e202300778, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38441412

RESUMO

A series of KF/Mg-Fe oxides were fabricated via the solid-state reaction between KF and Mg-Fe oxides. Especially, when 20 wt % KF was supported on the Mg-Fe bi-metal oxides and calcined at 400-600 °C, the solid material with more basic sites than the support itself was obtained. When applied as catalyst to dimethyl carbonate (DMC) synthesis through transesterification of ethylene carbonate (EC) and methanol, this material can afforded up to 88 % yield and 97 % selectivity toward DMC in 2 h under reflux conditions with the molar ratio of methanol to ethylene carbonate set at 8. It is worth noting that the catalyst was easily separated and reused, retaining at least 89 % catalytic activity during the first four recycles. Although an attenuated activity was still observed due to the inevitable filtration loss and dissolution, this solid base can still provide clues to the development recyclable catalyst in green synthesis of DMC.

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