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1.
J Neurophysiol ; 2024 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-38985939

RESUMEN

It is a hot problem in epilepsy research to detect and predict seizures by EEG signals. Clinically, it is generally observed that there are only sudden abnormal signals during the ictal stage, but there is no significant difference in the EEG signal between the interictal and preictal stages. To solve the problem that preictal signals are difficult to recognize clinically, and then effectively improve the recognition efficiency of epileptic seizures, so, in this paper, some nonlinear methods are comprehensively used to extract the hidden information in the EEG signals in different stages, namely, phase space reconstruction (PSR), Poincaré section (PS), synchroextracting transform (SET) and machine learning for EEG signal analysis. Firstly, PSR based on C-C method is used, and the results show that there are different diffuse attractor trajectories of the signals in different stages. Secondly, the confidence ellipse (CE) is constructed by using the scatter diagram of the corresponding trajectory on PS, and the aspect ratio and area of the ellipse are calculated. The results show that there is an interesting transitional phenomenon in preictal stage. To recognize ictal and preictal signals, time-frequency (TF) spectrums which are processed by SET are fed into the convolutional neural networks (CNN) classifier. The accuracy of recognize ictal and preictal signals reaches 99.7% and 93.7% respectively. To summarize, our results based on nonlinear method provide new research ideas for seizures detection and prediction.

2.
Org Lett ; 26(23): 4958-4962, 2024 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-38833318

RESUMEN

Inspired by previous selection outcomes, we investigated and developed a rhodium-promoted C-H activation/annulation reaction of DNA-linked terminal alkynes and aromatic acids. This reaction exhibits excellent efficiency with high conversions and a broad substrate scope. Most importantly, the unique DEL-compatible conditions provide a better scenario for yielding an isocoumarin scaffold compared to conventional organic reaction conditions, and this newly developed on-DNA method has confirmed its feasibility in preparing DNA-encoded libraries.


Asunto(s)
Alquinos , ADN , Rodio , Rodio/química , Alquinos/química , Estructura Molecular , ADN/química , Catálisis , Isocumarinas/química , Isocumarinas/síntesis química
3.
Langmuir ; 40(21): 11067-11077, 2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38739539

RESUMEN

In recent years, graphitic carbon nitride (g-C3N4) has attracted considerable attention because it includes earth-abundant carbon and nitrogen elements and exhibits good chemical and thermal stability owing to the strong covalent interaction in its conjugated layer structure. However, bulk g-C3N4 has some disadvantages of low specific surface area, poor light absorption, rapid recombination of photogenerated charge carriers, and insufficient active sites, which hinder its practical applications. In this study, we design and synthesize potassium single-atom (K SAs)-doped g-C3N4 porous nanosheets (CM-KX, where X represents the mass of KHP added) via supramolecular self-assembling and chemical cross-linking copolymerization strategies. The results show that the utilization of supramolecules as precursors can produce g-C3N4 nanosheets with reduced thickness, increased surface area, and abundant mesopores. In addition, the intercalation of K atoms within the g-C3N4 nitrogen pots through the formation of K-N bonds results in the reduction of the band gap and expansion of the visible-light absorption range. The optimized K-doped CM-K12 nanosheets achieve a specific surface area of 127 m2 g-1, which is 11.4 times larger than that of the pristine g-C3N4 nanosheets. Furthermore, the optimal CM-K12 sample exhibits the maximum H2 production rate of 127.78 µmol h-1 under visible light (λ ≥ 420 nm), which is nearly 23 times higher than that of bare g-C3N4. This significant improvement of photocatalytic activity is attributed to the synergistic effects of the mesoporous structure and K SAs doping, which effectively increase the specific surface area, improve the visible-light absorption capacity, and facilitate the separation and transfer of photogenerated electron-hole pairs. Besides, the optimal sample shows good chemical stability for 20 h in the recycling experiments. Density functional theory calculations confirm that the introduction of K SAs significantly boosts the adsorption energy for water and decreases the activation energy barrier for the reduction of water to hydrogen.

4.
Chem Sci ; 15(19): 7285-7292, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38756801

RESUMEN

Energy-efficient separation of C2H6/C2H4 is a great challenge, for which adsorptive separation is very promising. C2H6-selective adsorption has big implications, while the design of C2H6-sorbents with ideal adsorption capability, particularly with the C2H6/C2H4-selectivity exceeded 2.0, is still challenging. Instead of the current strategies such as chemical modification or pore space modulation, we propose a new methodology for the design of C2H6-sorbents. With a Cu-TCPP [TCPP = 5,10,15,20-tetrakis(4-carboxyphenyl)porphyrin] framework dispersed onto a microporous carbon and a hierarchical-pore carbon, two composite sorbents are fabricated. The composite sorbents exhibit enhanced C2H6-selective adsorption capabilities with visible light, particularly the composite sorbent based on the hierarchical-pore carbon, whose C2H6 and C2H4 adsorption capacities (0 °C, 1 bar) are targetedly increased by 27% and only 1.8% with visible light, and therefore, an C2H6-selectivity (C2H6/C2H4 = 10/90, v/v) of 4.8 can be realized. With visible light, the adsorption force of the C2H6 molecule can be asymmetrically enhanced by the excitation enriched electron density over the adsorption sites formed via the close interaction between the Cu-TCPP and the carbon layer, whereas that of the C2H4 molecule is symmetrically altered and the forces cancelled each other out. This strategy may open up a new route for energy-efficient adsorptive separation of C2H6/C2H4 with light.

7.
ACS Med Chem Lett ; 15(4): 555-564, 2024 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-38628804

RESUMEN

DNA-encoded library (DEL) technology is gaining attention for its rapid construction and deconvolution capabilities. Our study explored a novel strategy using rational DELs tailored for the SARS-CoV-2 papain-like protease, which revealed new fragments. Structural changes post-DEL screening mimic traditional medicinal chemistry lead optimization. We unveiled unique aromatic structures offering an alternative optimization path. Notably, we identified superior binding fragments targeting the BL2 groove. Derivative 16 emerged as the most promising by exhibiting IC50 values of 0.25 µM. Derivative 6, which features an aromatic fragment capped with a naphthalene moiety, showed IC50 values of 2.91 µM. Molecular modeling revealed hydrogen bond interactions with Lys157 residue and potential covalent interactions with nearby amino acid residues. This research underscored DEL's potential for fragment-based drug discovery against SARS-CoV-2 protease.

8.
J Ethnopharmacol ; 330: 118223, 2024 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-38642624

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Leonurus japonicus Houtt. (Labiatae), commonly known as Chinese motherwort, is a herbaceous flowering plant that is native to Asia. It is widely acknowledged in traditional medicine for its diuretic, hypoglycemic, antiepileptic properties and neuroprotection. Currently, Leonurus japonicus (Leo) is included in the Pharmacopoeia of the People's Republic of China. Traditional Chinese Medicine (TCM) recognizes Leo for its myriad pharmacological attributes, but its efficacy against ICH-induced neuronal apoptosis is unclear. AIMS OF THE STUDY: This study aimed to identify the potential targets and regulatory mechanisms of Leo in alleviating neuronal apoptosis after ICH. MATERIALS AND METHODS: The study employed network pharmacology, UPLC-Q-TOF-MS technique, molecular docking, pharmacodynamic studies, western blotting, and immunofluorescence techniques to explore its potential mechanisms. RESULTS: Leo was found to assist hematoma absorption, thus improving the neurological outlook in an ICH mouse model. Importantly, molecular docking highlighted JAK as Leo's potential therapeutic target in ICH scenarios. Further experimental evidence demonstrated that Leo adjusts JAK1 and STAT1 phosphorylation, curbing Bax while augmenting Bcl-2 expression. CONCLUSION: Leo showcases potential in mitigating neuronal apoptosis post-ICH, predominantly via the JAK/STAT mechanism.


Asunto(s)
Apoptosis , Hemorragia Cerebral , Leonurus , Simulación del Acoplamiento Molecular , Farmacología en Red , Neuronas , Animales , Apoptosis/efectos de los fármacos , Leonurus/química , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Ratones , Masculino , Hemorragia Cerebral/tratamiento farmacológico , Fármacos Neuroprotectores/farmacología , Fármacos Neuroprotectores/química , Fármacos Neuroprotectores/aislamiento & purificación , Extractos Vegetales/farmacología , Extractos Vegetales/química , Janus Quinasa 1/metabolismo , Factor de Transcripción STAT1/metabolismo , Modelos Animales de Enfermedad
9.
J Med Chem ; 67(5): 3778-3794, 2024 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-38482826

RESUMEN

It is an urgent need to tackle the global crisis of multidrug-resistant bacterial infections. We report here an innovative strategy for large-scale screening of new antibacterial agents using a whole bacteria-based DNA-encoded library (DEL) of vancomycin derivatives via peripheral modifications. A bacterial binding affinity assay was established to select the modification fragments in high-affinity compounds. The optimal resynthesized derivatives demonstrated excellently enhanced activity against various resistant bacterial strains and provided useful structures for vancomycin derivatization. This work presents the new concept in a natural product-templated DEL and in antibiotic discovery through bacterial affinity screening, which promotes the fight against drug-resistant bacteria.


Asunto(s)
Antibacterianos , Vancomicina , Vancomicina/farmacología , Vancomicina/química , Antibacterianos/química , Bacterias/metabolismo , Farmacorresistencia Bacteriana Múltiple , ADN , Pruebas de Sensibilidad Microbiana
10.
Pharmacol Res ; 203: 107161, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38554789

RESUMEN

Hepatocellular carcinoma is one of the leading causes of cancer-related mortality globally. The emergence of immunotherapy has been shown to be a promising therapeutic approach for hepatocellular carcinoma in recent years. It has been well known that T cell plays a key role in current immunotherapy. However, sustained exposure to antigenic stimulation within the tumor microenvironment may lead to T cell exhaustion, which may cause treatment ineffectiveness. Therefore, reversing T cell exhaustion has been an important issue for the clinical application of immunotherapy, and a comprehensive understanding of the intricacies surrounding T cell exhaustion and its underlying mechanisms is imperative for devising strategies to overcome the T cell exhaustion during treatment. In this review, we summarized the reported drivers of T cell exhaustion in hepatocellular carcinoma and delineate potential ways to reverse it. Additionally, we discussed the interplay among metabolic plasticity, epigenetic regulation, and transcriptional factors in exhausted T cells in hepatocellular carcinoma, and their implication for future clinical applications.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Linfocitos T , Microambiente Tumoral , Carcinoma Hepatocelular/inmunología , Carcinoma Hepatocelular/patología , Humanos , Neoplasias Hepáticas/inmunología , Neoplasias Hepáticas/patología , Animales , Linfocitos T/inmunología , Microambiente Tumoral/inmunología , Epigénesis Genética , Inmunoterapia , Agotamiento de Células T
12.
Clin Neurol Neurosurg ; 236: 108111, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-38199117

RESUMEN

OBJECTIVES: The purpose of this study was to evaluate the effectiveness of endoscopic endonasal surgery (EES) for Rathke's cleft cysts (RCCs) and the advantages of detailed preoperative imaging evaluation, intraoperative personalized removal and multilevel sellar floor reconstruction. METHODS: The clinical data of 43 patients with RCCs who were treated by EES in the neurosurgery department of affiliated hospital of Jiangnan University and Wuxi No.2 People's Hospital from January 2018 to January 2023 were retrospectively analyzed. The effectiveness of EES for RCCs was analyzed by imaging information, surgical procedures, symptom improvement and complications. RESULTS: All 43 RCCs were completely removed by EES, and all clinical symptoms improved to varying degrees. Postoperative relief of headache was achieved in 23 out of 26 patients (88.5 %); there was improvement in 10 out of 13 patients with visual field disorders (76.9 %) and in 8 out of 10 patients with endocrine abnormalities (80 %). New hormonal deficiency was discovered in 7 of all the patients postoperatively. There were 8 patients with postoperative diabetes insipidus and 1 patient with cerebrospinal fluid leakage. The incidence of new hormonal dysfunction and postoperative DI in expanded EES (33.3 %, 33.3 %) was higher than it in conventional EES (4 %, 8 %) (P < 0.05). The average follow-up time was 29.1 ± 14.8 months, and there were no deaths or infections. Three patients presented with cyst recurrence on MRI. CONCLUSIONS: The clinical manifestations and imaging characteristics of RCCs are variable, and a detailed preoperative review of the imaging is helpful for the development of surgical plans. RCCs can be treated more safely and thoroughly with less trauma and complications by intraoperative personalized removal and multilevel sellar floor reconstruction. The high incidence of new hormonal dysfunction and postoperative DI may be related to the disturbance of the pituitary stalk. EES has unique advantages and high clinical application value for the treatment of RCCs.


Asunto(s)
Quistes del Sistema Nervioso Central , Quistes , Neoplasias Hipofisarias , Humanos , Estudios Retrospectivos , Quistes del Sistema Nervioso Central/diagnóstico por imagen , Quistes del Sistema Nervioso Central/cirugía , Quistes del Sistema Nervioso Central/complicaciones , Endoscopía , Quistes/complicaciones , Hipófisis/diagnóstico por imagen , Hipófisis/cirugía , Neoplasias Hipofisarias/cirugía
13.
J Med Chem ; 67(2): 1079-1092, 2024 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-38166388

RESUMEN

The DNA-encoded library (DEL) is a powerful hit generation tool for chemical biology and drug discovery; however, the optimization of DEL hits remained a daunting challenge for the medicinal chemistry community. In this study, hit compounds targeting the WIN binding domain of WDR5 were discovered by the initial three-cycle linear DEL selection, and their potency was further enhanced by a cascade DEL selection from the focused DEL designed based on the original first run DEL hits. As expected, these new compounds from the second run of focused DEL were more potent WDR5 inhibitors in the protein binding assay confirmed by the off-DNA synthesis. Interestingly, selected inhibitors exhibited good antiproliferative activity in two human acute leukemia cell lines. Taken together, this new cascade DEL selection strategy may have tremendous potential for finding high-affinity leads against WDR5 and provide opportunities to explore and optimize inhibitors for other targets.


Asunto(s)
ADN , Descubrimiento de Drogas , Humanos , Biblioteca de Genes , Unión Proteica , ADN/metabolismo , Péptidos y Proteínas de Señalización Intracelular/metabolismo
14.
Cytokine Growth Factor Rev ; 75: 101-109, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-37658030

RESUMEN

Ferroptosis is a type of cell death characterized by iron-dependent phospholipid peroxidation and reactive oxygen species overproduction. Ferroptosis induces immunogenic cell death and elicits anti-tumor immune responses, playing an important role in cancer immunotherapy. Ferroptosis suppression in cancer cells impairs its immunotherapeutic efficacy. To overcome this issue, ferroptosis inducers (FINs) have been combined with other cancer therapies to create an anti-tumor immune microenvironment. However, the ferroptosis-based crosstalk between immune and tumor cells is complex because oxidative products released by ferroptotic tumor cells impair the functions of anti-tumor immune cells, resulting in immunotherapeutic resistance. In the present article, we have reviewed ferroptosis in tumor and immune cells and summarized the crosstalk between ferroptotic tumor cells and the immune microenvironment. Based on the existing literature, we have further discussed future perspectives on opportunities for combining ferroptosis-targeted therapies with cancer immunotherapies.


Asunto(s)
Ferroptosis , Neoplasias , Humanos , Inmunoterapia , Neoplasias/terapia , Especies Reactivas de Oxígeno , Microambiente Tumoral
15.
Org Lett ; 26(14): 2763-2767, 2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-37382883

RESUMEN

While DNA-encoded macrocyclic libraries have gained substantial attention and several hit compounds have been identified from DNA-encoded library technology, efficient on-DNA macrocyclic methods are also required to construct DNA-linked libraries with a high degree of cyclization and DNA integrity. In this paper, we reported a set of on-DNA methodologies, including the use of an OPA-mediated three-component cyclization with native handles of amino acids and photoredox chemistries. These chemistries proceed smoothly under mild conditions in good to excellent conversions, successfully generating novel isoindole, isoindoline, indazolone, and bicyclic scaffolds.


Asunto(s)
ADN , Péptidos , Ciclización , Péptidos/química , ADN/química , Biblioteca de Genes , Aminoácidos/química
16.
Nanoscale ; 16(2): 903-912, 2024 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-38108145

RESUMEN

Nanomedicines based on ferroptosis may be effective strategies for cancer therapy due to their unique inducing mechanism. However, the challenges, including non-target distribution, poor accumulation and retention of nanomedicine, have a profound impact on the effectiveness of drug delivery. Here, we developed cancer cell membrane (CCM)-coated Fe3O4 nanoparticles (NPs) modified with supramolecular precursors and loaded with sulfasalazine (SAS) for breast cancer therapy. Benefiting from the coating of the CCM, these NPs can be specifically recognized and internalized by tumor cells rapidly after being administered and form aggregates via the host-guest interaction between adamantane (ADA) and cyclodextrins (CD), which in turn effectively reduces the exocytosis of tumor cells and prolongs the retention time. In vitro and in vivo studies showed that Fe3O4 NPs possessed effective cellular uptake and precise specific accumulation in tumor cells and tissues through CCM-targeted supramolecular in situ aggregation, demonstrating enhanced ferroptosis-inducing therapy of breast cancer. Overall, this work provided a supramolecular biomimetic platform to achieve targeted delivery of Fe3O4 NPs with high efficiency and precise self-assembly for improved cancer therapy.


Asunto(s)
Neoplasias de la Mama , Ferroptosis , Nanopartículas , Humanos , Femenino , Neoplasias de la Mama/tratamiento farmacológico , Biomimética , Sistemas de Liberación de Medicamentos , Línea Celular Tumoral
17.
J Am Chem Soc ; 145(46): 25283-25292, 2023 11 22.
Artículo en Inglés | MEDLINE | ID: mdl-37857329

RESUMEN

DNA-encoded chemical library (DEL) has been extensively used for lead compound discovery for decades in academia and industry. Incorporating an electrophile warhead into DNA-encoded compounds recently permitted the discovery of covalent ligands that selectively react with a particular cysteine residue. However, noncysteine residues remain underexplored as modification sites of covalent DELs. Herein, we report the design and utility of tyrosine-targeting DELs of 67 million compounds. Proteome-wide reactivity analysis of tyrosine-reactive sulfonyl fluoride (SF) covalent probes suggested three enzymes (phosphoglycerate mutase 1, glutathione s-transferase 1, and dipeptidyl peptidase 3) as models of tyrosine-targetable proteins. Enrichment with SF-functionalized DELs led to the identification of a series of tyrosine-targeting covalent inhibitors of the model enzymes. In-depth mechanistic investigation revealed their novel modes of action and reactive ligand-accessible hotspots of the enzymes. Our strategy of combining activity-based proteome profiling and covalent DEL enrichment (ABPP-CoDEL), which generated selective covalent binders against a variety of target proteins, illustrates the potential use of this methodology in further covalent drug discovery.


Asunto(s)
Proteoma , Tirosina , Proteoma/química , Descubrimiento de Drogas/métodos , Bibliotecas de Moléculas Pequeñas/farmacología , Ligandos , ADN
18.
Cancer Lett ; 573: 216354, 2023 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-37625777

RESUMEN

Protein homeostasis, an important aspect of cellular fitness that encompasses the balance of production, folding and degradation of proteins, has been linked to several diseases of the human body. Multiple interconnected pathways coordinate to maintain protein homeostasis within the cell. Recently, the role of the protein homeostasis network in tumorigenesis and tumour progression has gradually come to light. Here, we summarize the involvement of the most prominent components of the protein quality control mechanisms (HSR, UPS, autophagy, UPR and ERAD) in tumour development and cancer immunity. In addition, evidence for protein quality control mechanisms and targeted drugs is outlined, and attempts to combine these drugs with cancer immunotherapy are discussed. Altogether, combination therapy represents a promising direction for future investigations, and this exciting insight will be further illuminated by the development of drugs that can reach a balance between the benefits and hazards associated with protein homeostasis interference.


Asunto(s)
Neoplasias , Proteostasis , Humanos , Neoplasias/terapia , Carcinogénesis , Sistemas de Liberación de Medicamentos , Inmunoterapia
19.
ACS Med Chem Lett ; 14(8): 1079-1087, 2023 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-37583816

RESUMEN

The use of small agonists to target stimulators of interferon genes (STING) has been demonstrated to be a promising strategy for the treatment of various cancers and infectious diseases. Herein, we discovered a series of 1H-pyrrole-3-carbonitrile derivatives as potential STING agonists. On this basis, the structure-activity relationship of this scaffold was studied by introducing various substituents on the aniline ring system. Representative compounds 7F, 7P, and 7R all displayed comparable activities to the reported STING agonist SR-717 in binding various hSTING alleles and induced reporter signal in human THP1 cell lines. Model compound 7F induced phosphorylation of TBK1, IRF3, p65, and STAT3 in a STING-dependent fashion and stimulated the expression of target genes IFNB1, CXCL10, and IL6 in a time-dependent manner in human THP1 cells. Our findings afforded a series of novel STING agonists with promising potential.

20.
ACS Med Chem Lett ; 14(8): 1073-1078, 2023 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-37583819

RESUMEN

Pyrimidine is a ubiquitous component in natural products and approved drugs, providing an ideal modular scaffold for generating libraries with drug-like properties. DNA-encoded library technology introduces a novel library modality where each small molecule is covalently linked to a unique oligo tag. This technology offers the advantages of rapidly generating and interrogating large-scale libraries containing billions of members, substantially reducing the entry barrier to their use in both academia and the pharmaceutical industry. In this Letter, we describe the synthesis of three DNA-encoded libraries based on different functionalized pyrimidine cores featuring diversified chemoselectivity and regioselectivity. Preliminary screening of these DNA-encoded libraries against BRD4 identified compounds with nanomolar inhibition activities.

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