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2.
J Am Chem Soc ; 146(19): 13546-13557, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38690842

RESUMO

Glycidic esters represent pivotal constituents in synthetic chemistry, offering enhanced versatility for tailoring toward a diverse array of molecular targets in comparison with simple epoxides. While considerable progress has been made in the asymmetric synthesis of trans- and trisubstituted glycidic esters, achieving enantioselective preparation of cis-glycidic esters has remained a long-standing challenge. Here, we demonstrate a selectivity-predictable modular platform for the asymmetric synthesis of cis-glycidic esters via a novel dinuclear (salen)titanium(III)-catalyzed radical-type kinetic resolution (KR) approach. This radical KR protocol operates under mild conditions and demonstrates a wide substrate scope, facilitating the synthesis of alkyl- and aryl-substituted cis-glycidic esters with high levels of regioselectivity and enantioselectivity, along with hydroxy ester byproducts representing synthetically valuable motifs as well. This study presents a unique exploration of radical-type KR applied to epoxides, effectively overcoming the steric challenges inherent in conventional nucleophilic-type methodologies typically employed in epoxide chemistry.

3.
Neurobiol Dis ; 192: 106428, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38307367

RESUMO

The heart and brain are the core organs of the circulation and central nervous system, respectively, and play an important role in maintaining normal physiological functions. Early neuronal and cardiac damage affects organ function. The relationship between the heart and brain is being continuously investigated. Evidence-based medicine has revealed the concept of the "heart- brain axis," which may provide new therapeutic strategies for certain diseases. Takeda protein-coupled receptor 5 (TGR5) is a metabolic regulator involved in energy homeostasis, bile acid homeostasis, and glucose and lipid metabolism. Inflammation is critical for the development and regeneration of the heart and brain during metabolic diseases. Herein, we discuss the role of TGR5 as a metabolic regulator of heart and brain development and injury to facilitate new therapeutic strategies for metabolic and ischemic diseases of the heart and brain.


Assuntos
Lesões Encefálicas , Doenças Metabólicas , Humanos , Receptores Acoplados a Proteínas G/metabolismo , Transdução de Sinais , Inflamação/metabolismo
4.
Biochem Biophys Res Commun ; 704: 149699, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38412668

RESUMO

With an increasing understanding of the mechanisms of fracture healing, it has been found that nerve injury plays a crucial role in the process, but the specific mechanism is yet to be completely revealed. To address this issue and provide novel insights for fracture treatment, we compiled this review. This review aims to study the impact of nerve injury on fracture healing, exploring the role of neurotrophic factors in the healing process. We first revisited the effects of the central nervous system (CNS) and the peripheral nervous system (PNS) on the skeletal system, and further explained the phenomenon of significantly accelerated fracture healing under nerve injury conditions. Then, from the perspective of neurotrophic factors, we delved into the physiological functions and mechanisms of neurotrophic factors, such as nerve growth factor (NGF), Neuropeptides (NPs), and Brain-derived neurotrophic factor (BDNF), in bone metabolism. These effects include direct actions on bone cells, improvement of local blood supply, regulation of bone growth factors, control of cellular signaling pathways, promotion of callus formation and bone regeneration, and synergistic or antagonistic effects with other endocrine factors, such as Sema3A and Transforming Growth Factor ß (TGF-ß). Finally, we discussed the treatments of fractures with nerve injuries and the future research directions in this review, suggesting that the relationship between nerve injury and fracture healing, as well as the role of nerve injury in other skeletal diseases.


Assuntos
Fraturas Ósseas , Neuropeptídeos , Doenças do Sistema Nervoso Periférico , Humanos , Consolidação da Fratura/fisiologia , Regeneração Óssea/fisiologia
5.
Bioorg Med Chem Lett ; 99: 129621, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38244941

RESUMO

The progress of organicsyntheticmethod can promote late-stage lead compound modification and novel active compound discovery. Molecular editing technology in the field of organic synthesis, including peripheral and skeletal editing, facilitates rapid access to molecular diversity of a lead compound. Peripheral editing of CH bond activation is gradually used in lead optimization to afford novel active scaffolds and chemical space exploitation. To develop oridonin derivatives with high anti-inflammatory potency, novel oridonin sulfamides had been designed and synthesized by a scaffoldhopping strategy based on a visible-light photocatalysis peripheral editing. All novel compounds revealed measurable inhibition of IL-1ß and low cytotoxicity in THP-1 cells. The docking study indicated that the best active compound ZM640 was accommodated in thebinding site of NLRP3 with two hydrogen bond interaction. These preliminary results confirm that α, ß-unsaturated carbonyl of oridonin is not essential for NLRP3 inhibitory effect. This new oridonin scaffold has its potential to be further developed as a promising class of NLRP3 inhibitors.


Assuntos
Antineoplásicos , Diterpenos do Tipo Caurano , Antineoplásicos/farmacologia , Proteína 3 que Contém Domínio de Pirina da Família NLR , Diterpenos do Tipo Caurano/farmacologia , Diterpenos do Tipo Caurano/química , Técnicas de Química Sintética
6.
Physiol Plant ; 176(1): e14197, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38344855

RESUMO

Increased acid phosphatase (APase) activity is a prominent feature of tomato (Solanum lycopersicum) responses to inorganic phosphate (Pi) restriction. SlPHL1, a phosphate starvation response (PHR) transcription factor, has been identified as a positive regulator of low Pi (LP)-induced APase activity in tomato. However, the molecular mechanism underlying this regulation remains to be elucidated. Here, SlPHL1 was found to positively regulate the LP-induced expression of five potential purple acid phosphatase (PAP) genes, namely SlPAP7, SlPAP10b, SlPAP12, SlPAP15, and SlPAP17b. Furthermore, we provide evidence that SlPHL1 can stimulate transcription of these five genes by binding directly to the PHR1 binding sequence (P1BS) located on their promoters. The P1BS mutation notably weakened SlPHL1 binding to the promoters of SlPAP7, SlPAP12, and SlPAP17b but almost completely abolished SlPHL1 binding to the promoters of SlPAP10b and SlPAP15. As a result, the transcriptional activation of SlPHL1 on SlPAP10b and SlPAP15 was substantially diminished. In addition, not only did transient overexpression of either SlPAP10b or SlPAP15 in tobacco leaves increase APase activity, but overexpression of SlPAP15 in Arabidopsis and tomato also increased APase activity and promoted plant growth. Subsequently, two SPX proteins, SlSPX1 and SlSPX4, were shown to physically interact with SlPHL1. Moreover, SlSPX1 inhibited the transcriptional activation of SlPHL1 on SlPAP10b and SlPAP15 and negatively regulated the activity of APase. Taken together, these results demonstrate that SlPHL1-mediated LP signaling promotes APase activity by activating the transcription of SlPAP10b and SlPAP15, which may provide valuable insights into the mechanisms of tomato response to Pi-limited stress.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Solanum lycopersicum , Fosfatos , Solanum lycopersicum/genética , Fatores de Transcrição/metabolismo , Arabidopsis/metabolismo , Fosfatase Ácida/genética , Fosfatase Ácida/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas de Arabidopsis/metabolismo
7.
J Environ Manage ; 360: 121023, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38733837

RESUMO

Solar-induced chlorophyll fluorescence (SIF) has been used since its discovery to characterize vegetation photosynthesis and is an effective tool for monitoring vegetation dynamics. Its response to meteorological drought enhances our comprehension of the ecological consequences and adaptive mechanisms of plants facing water scarcity, informing more efficient resource management and efforts in mitigating climate change. This study investigates the spatial and temporal patterns of SIF and examines how vegetation SIF in the Yellow River Basin (YRB) responds to meteorological drought. The findings reveal a gradual southeast-to-northwest decline in SIF across the Yellow River Basin, with an overall increase-from 0.1083 W m-2µm-1sr-1 in 2001 to 0.1468 W m-2µm-1sr-1 in 2019. Approximately 96% of the YRB manifests an upward SIF trend, with 75% of these areas reaching statistical significance. The Standardized Precipitation Evapotranspiration Index (SPEI) at a time scale of 4 months (The SPEI-4), based on the Liang-Kleeman information flow method, is identified as the most suitable drought index, adeptly characterizing the causal relationship influencing SIF variations. As drought intensified, the SPEI-4 index markedly deviated from the baseline, resulting in a decrease in SIF values to their lowest value; subsequently, as drought lessened, it gravitated towards the baseline, and SIF values began to gradually increase, eventually recovering to near their annual maximum. The key finding is that the variability of SIF with SPEI is relatively pronounced in the early growing season, with forests demonstrating superior resilience compared to grasslands and croplands. The responsiveness of vegetation SIF to SPEI can facilitate the establishment of effective drought early warning systems and promote the rational planning of water resources, thereby mitigating the impacts of climate change.


Assuntos
Clorofila , Mudança Climática , Secas , Rios , Fluorescência , Luz Solar , Fotossíntese
8.
Environ Geochem Health ; 46(4): 135, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38483670

RESUMO

Some Polycyclic Aromatic Compounds (PACs) such as nitrated-PAHs (NPAHs), oxygenated-PAHs (OPAHs) and methyl-PAHs (MPAHs) have attracted significant concern due to derivatives have greater potential to be more toxic at low environmental concentrations compared to their PPAHs, particularly in petrochemical industrial region and its surrounding areas surface soils in China. Hence, this article provides an insight into the fate, sources, impacts, and relevance to the external environment of PAH-derivatives based on important emissions source. Moreover, prospective health risk due to their exposure has also been discussed. In this study, the concentration (10-3 ng/g) of Æ©18PPAHs, Æ©11MPAHs, Æ©12NPAHs, and Æ©4OPAHs in the park were 9.67 ± 1.40, 3.24 ± 0.54, 0.03 ± 0.02 and 0.19 ± 0.65, respectively, which were 4.47, 3.89, 2.04 and 1.17 times than of them surrounding the region. A decreasing trend of the low molecular weight (2-4Rings) contribution to the total amount of PAHs, while the fraction of high molecular weight (5-6Rings) species showed the opposite trend. According to the principal component analysis (PCA) and diagnostic ratios indicated PAHs in the soil samples have mixed sources from industrial activities, solid fuel combustion, and heavy traffic. Despite the high concentrations of MPAHs and OPAHs, the toxicity equivalency quotients (TEQs) of them were not calculated due to the lack of toxic equivalent factors (TEF), thus current studies on PAH and derivatives could have underestimated their exposure risks. The quality and sustainable management of soils are crucial for human health and sustainable development, while there is lack of public awareness of the severe issue of soil pollution. It is recommended to conduct more intensive monitoring and regional assessments in the future.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos , Compostos Policíclicos , Poluentes do Solo , Humanos , Compostos Policíclicos/análise , Monitoramento Ambiental , Solo , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Hidrocarbonetos Policíclicos Aromáticos/análise , China , Poluentes do Solo/toxicidade , Poluentes do Solo/análise , Medição de Risco
9.
Zhongguo Zhong Yao Za Zhi ; 49(7): 1947-1955, 2024 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-38812207

RESUMO

This study aims to decipher the mechanism of sinomenine in inhibiting platelet-derived growth factor/platelet-derived growth factor receptor(PDGF/PDGFR) signaling pathway in rheumatoid arthritis-fibroblast-like synoviocyte(RA-FLS) migration induced by neutrophil extracellular traps(NETs). RA-FLS was isolated from the synovial tissue of 3 RA patients and cultured. NETs were extracted from the peripheral venous blood of 4 RA patients and 4 healthy control(HC). RA-FLS was classified into control group, HC-NETs group, RA-NETs group, RA-NETs+sinomenine group and RA-NETs+sinomenine+CP-673451 group. RNA-sequencing(RNA-seq) was conducted to identify the differentially expressed genes between HC-NETs and RA-NETs groups. Sangerbox was used to perform the Gene Ontology(GO) function and the Kyoto Encyclopedia of Genes and Genomes(KEGG) pathway enrichment. Cytoscape was employed to build the protein-protein interaction(PPI) network. AutoDock Vina and PyMOL were used for molecular docking of sinomenine with PDGFß and PDGFRß. The cell proliferation and migration were determined by the cell counting kit-8(CCK-8) and cell scratch assay, respectively. Western blot was employed to determine the protein level of PDGFRß. Real-time quantitative polymerase chain reaction(RT-qPCR) was carried out to determine the mRNA levels of matrix metalloproteinases(MMPs). The results revealed that neutrophils in RA patients were more likely to produce NETs. Compared with HC-NETs group, RA-NETs group showed up-regulated expression of PDGFß and PDGFRß. Compared with control group, RA-NETs group showed increased cell proliferation and migration and up-regulated protein level of PDGFRß and mRNA levels of PDGFß, PDGFRß, MMP1, MMP3, and MMP9(P<0.05). Compared with RA-NETs group, RA-NETs+sinomenine group presented decreased cell proliferation and migration and down-regulated protein and mRNA level of PDGFRß and mRNA levels of MMP1, MMP3, and MMP9(P<0.05). Compared with RA-NETs+sinomenine group, the proliferation ability of RA-NETs+sinomenine+CP-673451 group decreased(P<0.05). The findings prove that sinomenine reduces the RA-NETs-induced RA-FLS migration by inhibiting PDGF/PDGFR signaling pathway, thus mitigating RA.


Assuntos
Artrite Reumatoide , Movimento Celular , Morfinanos , Fator de Crescimento Derivado de Plaquetas , Transdução de Sinais , Sinoviócitos , Humanos , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/genética , Artrite Reumatoide/metabolismo , Movimento Celular/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Morfinanos/farmacologia , Sinoviócitos/efeitos dos fármacos , Sinoviócitos/metabolismo , Fator de Crescimento Derivado de Plaquetas/genética , Fator de Crescimento Derivado de Plaquetas/metabolismo , Receptores do Fator de Crescimento Derivado de Plaquetas/genética , Receptores do Fator de Crescimento Derivado de Plaquetas/metabolismo , Neutrófilos/efeitos dos fármacos , Neutrófilos/metabolismo , Masculino , Feminino , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo
10.
Zhongguo Zhong Yao Za Zhi ; 49(9): 2385-2392, 2024 May.
Artigo em Chinês | MEDLINE | ID: mdl-38812139

RESUMO

This study aims to investigate the mechanism of total saponins of Paridis Rhizoma in inducing the ferroptosis of MCF-7 cells and provide a theoretical basis for the clinical treatment of breast cancer with total saponins of Paridis Rhizoma. The methyl thiazolyl tetrazolium(MTT) assay was employed to examine the effects of different concentrations of total saponins of Paridis Rhizoma on the proliferation of MCF-7 cells. A phase contrast inverted microscope was used to observe the morphological changes of MCF-7 cells. The colony formation assay was employed to test the colony formation of MCF-7 cells. The lactate dehydrogenase(LDH) release test was conducted to determine the cell membrane integrity of MCF-7 cells. The cell scratch assay was employed to examine the migration of MCF-7 cells. After that, the level of reactive oxygen species(ROS) in MCF-7 cells was observed by an inverted fluorescence microscope, and the content of Fe~(2+) in MCF-7 cells was detected by the corresponding kit. Transmission electron microscopy was employed to observe the mitochondrial ultrastructure of MCF-7 cells. Western blot was employed to determine the expression of ferroptosis-related proteins, such as p53, solute carrier family 7 member 11(SLC7A11), glutathione peroxidase 4(GPX4), acyl-CoA synthetase long-chain family member 4(ACSL4), and transferrin receptor protein 1(TFR1) in MCF-7 cells. The results showed that 1.5, 3, 4.5, 6, 7.5, and 9 µg·mL~(-1) total saponins of Paridis Rhizoma significantly inhibited the proliferation of MCF-7 cells, with the IC_(50) of 4.12 µg·mL~(-1). Total saponins of Paridis Rhizoma significantly damaged the morphology of MCF-7 cells, leading to the formation of vacuoles and the gradual shrinkage and detachment of cells. Meanwhile, total saponins of Paridis Rhizoma inhibited the colony formation of MCF-7 cells, destroyed the cell membrane(leading to the release of LDH), and shortened the migration distance of MCF-7 cells. Total saponins of Paridis Rhizoma treatment significantly increased the content of ROS, induced oxidative damage, and led to the accumulation of Fe~(2+) in MCF-7 cells. Furthermore, total saponins of Paridis Rhizoma changed the mitochondrial structure, increased the mitochondrial membrane density, led to the decrease or even disappear of ridges, promoted the expression of p53 protein, down-regulated the expression of SLC7A11 and GPX4, and up-regulated the expression of ACSL4 and TFR1. In summary, total saponins of Paridis Rhizoma can significantly inhibit the proliferation and migration of MCF-7 cells and destroy the cell structure by inducing ferroptosis.


Assuntos
Neoplasias da Mama , Ferroptose , Espécies Reativas de Oxigênio , Rizoma , Saponinas , Humanos , Saponinas/farmacologia , Saponinas/química , Ferroptose/efeitos dos fármacos , Células MCF-7 , Rizoma/química , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Neoplasias da Mama/genética , Espécies Reativas de Oxigênio/metabolismo , Feminino , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/química , Proliferação de Células/efeitos dos fármacos , Primulaceae/química
11.
J Am Chem Soc ; 145(38): 21122-21131, 2023 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-37722078

RESUMO

The development of catalytic and enantioselective transformations for the synthesis of all-carbon quaternary stereocenters has long been recognized as a significant challenge in organic synthesis. While considerable progress has been made in asymmetric allylations, their potential to functionalize the commonly used synthon, epoxide, remains largely underexplored. Here we demonstrate the first highly regio- and enantioselective allylation of epoxides that delivers a range of quaternary stereocenters in the face of potentially problematic elimination and protonation reactions. The reaction proceeds via a radical approach under mild conditions and benefits from the use of earth-abundant titanium with a highly sophisticated salen ligand, which facilitates remarkable enantiocontrol and suppresses undesired side reactions. The resulting allylation products are multifunctional building blocks that can be elaborated chemo- and stereoselectively to a broad array of stereodefined structural motifs.

12.
J Am Chem Soc ; 145(29): 16228-16237, 2023 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-37460135

RESUMO

EGFR tyrosine kinase inhibitors have made remarkable success in targeted cancer therapy. However, therapeutic resistance inevitably occurred and EGFR-targeting therapy has been demonstrated to have limited efficacy or utility in glioblastoma, colorectal cancer, and hepatocellular carcinoma. Therefore, there is a high demand for the development of new targets to inhibit EGFR signaling. Herein, we found that the EGFR oncogene proximal promoter sequence forms a unique type of snap-back loop containing G-quadruplex (G4), which can be targeted by small molecules. For the first time, we determined the NMR solution structure of this snap-back EGFR-G4, a three-tetrad-core, parallel-stranded G4 with naturally occurring flanking residues at both the 5'-end and 3'-end. The snap-back loop located at the 3'-end region forms a stable capping structure through two stacked G-triads connected by multiple potential hydrogen bonds. Notably, the flanking residues are consistently absent in reported snap-back G4s, raising the question of whether such structures truly exist under in vivo conditions. The resolved EGFR-G4 structure has eliminated the doubt and showed distinct structural features that distinguish it from the previously reported snap-back G4s, which lack the flanking residues. Furthermore, we found that the snap-back EGFR-G4 structure is highly stable and can form on an elongated DNA template to inhibit DNA polymerase. The unprecedented high-resolution EGFR-G4 structure has thus contributed a promising molecular target for developing alternative EGFR signaling inhibitors in cancer therapeutics. Meanwhile, the two stacked triads may provide an attractive site for specific small-molecule targeting.


Assuntos
Quadruplex G , Neoplasias , Humanos , Regiões Promotoras Genéticas , Oncogenes , Receptores ErbB/genética
13.
Hum Mol Genet ; 30(23): 2300-2314, 2021 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-34245260

RESUMO

Here, we report on six unrelated individuals, all presenting with early-onset global developmental delay, associated with impaired motor, speech and cognitive development, partly with developmental epileptic encephalopathy and physical dysmorphisms. All individuals carry heterozygous missense variants of KCND2, which encodes the voltage-gated potassium (Kv) channel α-subunit Kv4.2. The amino acid substitutions associated with the variants, p.(Glu323Lys) (E323K), p.(Pro403Ala) (P403A), p.(Val404Leu) (V404L) and p.(Val404Met) (V404M), affect sites known to be critical for channel gating. To unravel their likely pathogenicity, recombinant mutant channels were studied in the absence and presence of auxiliary ß-subunits under two-electrode voltage clamp in Xenopus oocytes. All channel mutants exhibited slowed and incomplete macroscopic inactivation, and the P403A variant in addition slowed activation. Co-expression of KChIP2 or DPP6 augmented the functional expression of both wild-type and mutant channels; however, the auxiliary ß-subunit-mediated gating modifications differed from wild type and among mutants. To simulate the putative setting in the affected individuals, heteromeric Kv4.2 channels (wild type + mutant) were studied as ternary complexes (containing both KChIP2 and DPP6). In the heteromeric ternary configuration, the E323K variant exhibited only marginal functional alterations compared to homomeric wild-type ternary, compatible with mild loss-of-function. By contrast, the P403A, V404L and V404M variants displayed strong gating impairment in the heteromeric ternary configuration, compatible with loss-of-function or gain-of-function. Our results support the etiological involvement of Kv4.2 channel gating impairment in early-onset monogenic global developmental delay. In addition, they suggest that gain-of-function mechanisms associated with a substitution of V404 increase epileptic seizure susceptibility.


Assuntos
Deficiências do Desenvolvimento/etiologia , Deficiências do Desenvolvimento/metabolismo , Variação Genética , Ativação do Canal Iônico , Canais de Potássio Shal/genética , Canais de Potássio Shal/metabolismo , Alelos , Substituição de Aminoácidos , Biomarcadores , Deficiências do Desenvolvimento/diagnóstico , Suscetibilidade a Doenças , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Mutação , Fenótipo , Subunidades Proteicas , Canais de Potássio Shal/química
14.
Small ; 19(31): e2206080, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36436834

RESUMO

Multicolored phosphorescent materials based on carbon dots (CDs) constructed using the same or similar precursors with long lifetimes are conducive to their wide range of practical applications due to the developed compatibility. Herein, a universal method is developed to prepare long-lived multicolored phosphorescent CD-based composites for which heavy-metal doping is not required. The multicolored CDs are encapsulated in silica via silane hydrolysis, which forms many covalent SiOC and SiC bonds; hence, the vibrations and rotations of the luminescent centers on the CD surfaces are hindered. The transformation of SiOC to a more rigid SiC moiety occurs during high-temperature calcination. Furthermore, during calcination, the silica collapses, resulting in more tightly encapsulated CDs. The synergistic effect of these two calcination phenomena produces blue, green, yellow, and red phosphorescence, at wavelengths spanning 465 to 680 nm and with lifetimes of up to 2.11 s. Taking advantage of their superior phosphorescence performances, the CD-based composites are successfully applied to 3D multichannel information storage and encryption.

15.
Small ; 19(24): e2207983, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36843250

RESUMO

As a new type of solution-processed nano-laser material, carbon dots (CDs) have shown considerable potential in optical communication, laser displays, micro/nano processing, and biomedicine. Reducing the laser threshold of the gain material is of considerable significance for further development of CDs' applications in the field of micro/nano lasers. A series of blue-emissive CDs (B-CDs) are synthesized by changing the molar ratios of the precursors (citric acid (CA): L-Cysteine (L-Cys)). B-CDs have a structure of carbon nanoparticles with their surface being modified with 5-oxo-3,5-dihydro-2Hthiazolo [3,2-a]pyridine-7-carboxylic acid (TPCA). The laser can only be generated when the molar ratio of the precursors is between 1:1 and 2:1. With an increase in this ratio, the laser threshold decreases from 341.6 to 165.5 mJ cm-2 . The decrease in the laser threshold is attributed to the increase in the radiation transition rate and centralized sp3 -related excited state levels, which are favorable for light amplification and population inversion. These results will be instructional for the reasonably design of CDs-based laser materials and prompt their potential use in practical photonics.

16.
Mol Pharm ; 20(2): 875-885, 2023 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-36689197

RESUMO

Chlorin e6 (Ce6) has been extensively researched and developed as an antitumor therapy. Ce6 is a highly effective photosensitizer and sonosensitizer with promising future applications in photodynamic therapy, dynamic acoustic therapy, and combined acoustic and light therapy for tumors. Ce6 is also being studied for other applications in fluorescence navigation, antibacterials, and plant growth regulation. Here we review the role and research status of Ce6 in tumor therapy and the problems and challenges of its clinical application. Other biomedical effects of Ce6 are also briefly discussed. Despite the difficulties in clinical application, Ce6 has significant advantages in photodynamic therapy (PDT)/sonodynamic therapy (SDT) against cancer and offers several possibilities in clinical utility.


Assuntos
Clorofilídeos , Neoplasias , Fotoquimioterapia , Porfirinas , Humanos , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Neoplasias/tratamento farmacológico , Porfirinas/farmacologia , Porfirinas/uso terapêutico , Linhagem Celular Tumoral
17.
Nature ; 549(7672): 379-383, 2017 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-28902843

RESUMO

Constituting approximately 10% of flowering plant species, orchids (Orchidaceae) display unique flower morphologies, possess an extraordinary diversity in lifestyle, and have successfully colonized almost every habitat on Earth. Here we report the draft genome sequence of Apostasia shenzhenica, a representative of one of two genera that form a sister lineage to the rest of the Orchidaceae, providing a reference for inferring the genome content and structure of the most recent common ancestor of all extant orchids and improving our understanding of their origins and evolution. In addition, we present transcriptome data for representatives of Vanilloideae, Cypripedioideae and Orchidoideae, and novel third-generation genome data for two species of Epidendroideae, covering all five orchid subfamilies. A. shenzhenica shows clear evidence of a whole-genome duplication, which is shared by all orchids and occurred shortly before their divergence. Comparisons between A. shenzhenica and other orchids and angiosperms also permitted the reconstruction of an ancestral orchid gene toolkit. We identify new gene families, gene family expansions and contractions, and changes within MADS-box gene classes, which control a diverse suite of developmental processes, during orchid evolution. This study sheds new light on the genetic mechanisms underpinning key orchid innovations, including the development of the labellum and gynostemium, pollinia, and seeds without endosperm, as well as the evolution of epiphytism; reveals relationships between the Orchidaceae subfamilies; and helps clarify the evolutionary history of orchids within the angiosperms.


Assuntos
Evolução Molecular , Genoma de Planta/genética , Orchidaceae/genética , Filogenia , Genes de Plantas/genética , Orchidaceae/anatomia & histologia , Orchidaceae/classificação , Transcriptoma
18.
Graefes Arch Clin Exp Ophthalmol ; 261(3): 723-734, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36576571

RESUMO

PURPOSE: This study was aimed at exploring the function of Exosomes isolated from bone marrow-derived mesenchymal stem cells (BMSC-Exos) in corneal wound healing and at revealing the underlying mechanisms involving the p44/42 mitogen-activated protein kinase (MAPK) pathway. METHODS: The isolated BMSC-Exos were identified by transmission electron microscopy, Western blot, and nanoparticle tracking analysis. After coculture with BMSC-Exos, the proliferation and migration of human corneal epithelial cells (HCEs) were evaluated. The protein expression of p-MEK/MEK and p44/42 MAPK was detected by Western blot. A mouse model of alkali-burned cornea was established via NaOH exposure. After injection with BMSC-Exos, the pathological changes and expression of α-SMA (a fibrosis marker) and CD31 (a vascularization marker) in corneal tissues were detected. RESULTS: BMSC-Exos enhanced the proliferation and migration of HCEs in a dose-dependent manner. The p44/42 MAPK pathway was activated by the treatment of BMSC-Exos, and its blocking using U0126 partially abrogated the effects of BMSC-Exos on promoting the proliferation and migration of HCEs. In vivo, the injection of BMSC-Exos facilitated the remission of the pathological changes (inflammation) and weakened the upregulation of α-SMA (fibrosis) and CD31 (vascularization) in corneal tissues of mice with alkali-burn injury. CONCLUSION: BMSC-Exos promoted the proliferation and migration of HCEs via activating the p44/42 MAPK pathway in vitro and also inhibited alkali burn-induced inflammation, fibrosis, and vascularization in corneal tissues in vivo. BMSC-Exos may be promising resources for promoting corneal wound healing.


Assuntos
Exossomos , Células-Tronco Mesenquimais , Humanos , Camundongos , Animais , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Medula Óssea , Cicatrização , Córnea , Inflamação/metabolismo , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo
19.
J Biopharm Stat ; 33(1): 77-89, 2023 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-35649152

RESUMO

Clinical studies are generally required to characterize the accuracy of new diagnostic tests. In some cases, historical data are available from a predicate device, which is directly relevant to the new test. If this data can be appropriately incorporated into the new test study design, there is an opportunity to reduce the sample size and trial duration for the new test. One approach to achieve this is the Bayesian power prior method, which allows for the historical information to be down-weighted via a power parameter. We propose a dynamic method to calculate the power parameter based on first comparing the data between the historical and new data sources using a one-sided comparison, and second mapping the comparison probability through a scaled-Weibull discount function to tune the effective sample size borrowed. This pragmatic and conservative approach is embedded in an adaptive trial framework allowing for the trial to stop early for success. An example is presented for a new test developed to detect Methicillin-resistant Staphylococcus aureus present in the nasal carriage.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Humanos , Teorema de Bayes , Estudos Prospectivos , Projetos de Pesquisa , Testes Diagnósticos de Rotina
20.
Int J Mol Sci ; 24(11)2023 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-37298626

RESUMO

The overuse of copper-based fertilizers and pesticides over the last few decades has resulted in detrimental risks to our environment. Nano-enabled agrichemicals with a high effective utilization ratio have shown great potential for maintaining or minimizing environmental issues in agriculture. Copper-based nanomaterials (Cu-based NMs) serve as a promising alternative to fungicides. Three types of Cu-based NMs with different morphologies were analyzed for their different antifungal effects on Alternaria alternata in this current study. Compared to commercial copper hydroxide water power (Cu(OH)2 WP), all tested Cu-based NMs, including cuprous oxide nanoparticles (Cu2O NPs), copper nanorods (Cu NRs) and copper nanowires (Cu NWs), especially Cu2O NPs and Cu NWs, showed higher antifungal activity against Alternaria alternata. Its EC50 were 104.24 and 89.40 mg L-1, respectively, achieving comparable activity using a dose approximately 1.6 and 1.9-fold lower. Cu-based NMs could introduce the downregulation of melanin production and soluble protein content. In contrast to trends in antifungal activity, Cu2O NPs showed the strongest power in regulating melanin production and protein content and similarly exhibited the highest acute toxicity to adult zebrafish compared to other Cu-based NMs. These results demonstrate that Cu-based NMs could offer great potential in plant disease management strategies.


Assuntos
Cobre , Nanoestruturas , Animais , Cobre/química , Antifúngicos/farmacologia , Peixe-Zebra/metabolismo , Melaninas , Alternaria/metabolismo
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