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1.
iScience ; 27(6): 109982, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38840837

RESUMO

The swift advancement of the solid oxide fuel cell (SOFC) sector necessitates a harmony between electrode performance and commercialization cost. The economic value of elements is frequently linked to their abundance in the Earth's crust. Here, we develop abundant rare-earth iron perovskite electrodes of Ln0.6Sr0.4FeO3-δ (Ln = La, Pr, and Nd) with high abundant rare-earth metals and preferred iron metal for SOFCs. All three symmetric electrode materials display a cubic perovskite phase and excellent chemical compatibility with Gd0.2Ce0.8O2-δ electrolyte. All three electrodes possess exceptional surface oxygen exchange ability. At 800°C, single cells with La0.6Sr0.4FeO3-δ, Pr0.6Sr0.4FeO3-δ, and Nd0.6Sr0.4FeO3-δ symmetric electrodes attained excellent open circuit voltages of 1.108, 1.101, and 1.097 V, respectively, as well as peak powers of 213.52, 281.12, and 254.58 mW cm-2. The results suggest that overall performance of abundant rare-earth iron perovskite electrodes has a favorable impact on the extensive expansion of SOFCs, presenting significant potential for practical applications.

2.
J Med Chem ; 67(11): 9194-9213, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38829718

RESUMO

The epigenetic target CREB (cyclic-AMP responsive element binding protein) binding protein (CBP) and its homologue p300 were promising therapeutic targets for the treatment of acute myeloid leukemia (AML). Herein, we report the design, synthesis, and evaluation of a class of CBP/p300 PROTAC degraders based on our previously reported highly potent and selective CBP/p300 inhibitor 5. Among the compounds synthesized, 11c (XYD129) demonstrated high potency and formed a ternary complex between CBP/p300 and CRBN (AlphaScreen). The compound effectively degraded CBP/p300 proteins and exhibited greater inhibition of growth in acute leukemia cell lines compared to its parent compound 5. Furthermore, 11c demonstrated significant inhibition of tumor growth in a MOLM-16 xenograft model (TGI = 60%) at tolerated dose schedules. Our findings suggest that 11c is a promising lead compound for the treatment of AML.


Assuntos
Antineoplásicos , Leucemia Mieloide Aguda , Humanos , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/patologia , Leucemia Mieloide Aguda/metabolismo , Animais , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/síntese química , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Camundongos , Proteína p300 Associada a E1A/antagonistas & inibidores , Proteína p300 Associada a E1A/metabolismo , Relação Estrutura-Atividade , Descoberta de Drogas , Proteína de Ligação a CREB/antagonistas & inibidores , Proteína de Ligação a CREB/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto , Fatores de Transcrição de p300-CBP/antagonistas & inibidores , Fatores de Transcrição de p300-CBP/metabolismo , Proteólise/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos
3.
Front Public Health ; 12: 1394023, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38887249

RESUMO

To date, few FDA-approved medical countermeasures are available for addressing hematopoietic acute radiation syndrome (H-ARS). In this study, we present our latest research findings focusing on the evaluation of a novel radiation mitigator known as the mitigating amino acid mixture (MAAM). MAAM is composed of five amino acids as the recently reported amino acid-based oral rehydration solution for mitigating gastrointestinal (GI)-ARS. CD2F1 male and female mice were exposed to 60Co-γ total body irradiation (TBI) at 9.0 or 9.5 Gy. Following irradiation, mice were orally administered with MAAM or a saline vehicle control once daily for a duration of 14 days, commencing 24 h after TBI. Mouse survival and body weight change were monitored for 30 days after irradiation. Complete blood counts (CBCs), bone marrow (BM) stem and progenitor cell survival (clonogenicity), and a serum cytokine antibody array were analyzed using samples from day 30 surviving mice. Our data revealed that MAAM treatment significantly enhanced survival rates in irradiated male CD2F1 mice, and the survival rate increased from 25% in the vehicle control group to 60% in the MAAM-treated group (p < 0.05) after 9.0 Gy TBI. The number of BM colonies significantly increased from 41.8 ± 6.4 /104 cells (in the vehicle group) to 78.5 ± 17.0 /104 cells (in the MAAM group) following 9.0 Gy TBI. Furthermore, MAAM treatment led to a decrease in the levels of six cytokines/proteins [cluster of differentiation 40 (CD40), interleukin (IL)-17A, C-X-C motif chemokine 10 (CXCL10/CRG-2), cutaneous T cell-attracting chemokine (CTACK), macrophage inflammatory protein (MIP)-3ß, and IL-1ß] and an increase in the levels of five other cytokines/proteins [IL-3Rß, IL-5, leptin, IL-6, and stem cell factor (SCF)] in mouse serum compared to the vehicle group after 9.0 Gy TBI. However, similar alleviating effects of MAAM were not observed in the irradiated CD2F1 female mice. The serum cytokine profile in the irradiated female mice was different compared to the irradiated male mice. In summary, our data suggest that the beneficial effects of the mitigative amino acid combination treatment after radiation exposure may depend on sex.


Assuntos
Aminoácidos , Irradiação Corporal Total , Animais , Feminino , Masculino , Camundongos , Síndrome Aguda da Radiação/tratamento farmacológico , Citocinas/metabolismo , Fatores Sexuais , Protetores contra Radiação/farmacologia , Protetores contra Radiação/uso terapêutico
4.
Int J Surg ; 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38896858

RESUMO

BACKGROUND: Extracorporeal shockwave therapy (ESWT) is a traditional non-invasive therapy to treat osteonecrosis of the femur head (ONFH). This systematic review aims to investigate whether ESWT can improve the clinical function of ONFH and whether differences in improvement can be observed in radiographic outcomes. MATERIALS AND METHODS: Two authors independently searched PubMed, Embase, Cochrane Library, and Web of Science for English articles until October 21, 2023. After screening and reading the literature, the two authors independently used corresponding scales to evaluate the quality of the included articles and extracted data. The key data extracted included the Harris Hip Score (HHS), Visual Analog Scale (VAS), changes in lesion size, the change in the Association Research Circulation Osseous (ARCO) stage, and bone marrow edema stage. RESULTS: Nine articles included 468 males and 248 females. The average age was 43.29 years and the mean follow-up time was 15.19 months. After receiving ESWT, five studies involving 146 hips showed a higher HHS (MD=-33.38; 95%CI, -46.31, -20.45), and the difference was statistically significant (P<0.00001). The average VAS before treatment was above 5, but it dropped to 1.2 after ESWT (MD=4.64; 95%CI, 3.63, 5.64), and the difference was statistically significant (P<0.00001). Three studies found no significant differences in the areas of femoral head necrosis before and after treatment with ESWT(MD=9.66; 95%CI, -0.36, 19.67; P=0.06; I2=84%). Two articles showed that the use of ESWT had no significant effect on the change in the ARCO stage (MD=1.11; 95%CI, 0.76, 1.62; P=0.60; I2=0%). Three studies indicated that using ESWT could improve the bone marrow edema symptom in the early stage of ONFH (MD=4.35; 95%CI, 1.32, 14.37; P=0.02; I2=62%). CONCLUSION: Based on the current evidence, ESWT shows promise as a therapy to enhance hip function and alleviate pain in the early stage of ONFH. With the advancement of more precise imaging techniques, ESWT can potentially reduce the area affected by ONFH. However, such reduction was not found to be statistically significant at the imaging level. Additionally, ESWT could improve symptoms of bone marrow edema in the early stage. However, no significant change in ARCO grade was observed with ESWT treatment.

5.
Front Public Health ; 12: 1365161, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38807988

RESUMO

Introduction: Treatments that currently exist in the strategic national stockpile for acute radiation syndrome (ARS) focus on the hematopoietic subsyndrome, with no treatments on gastrointestinal (GI)-ARS. While the gut microbiota helps maintain host homeostasis by mediating GI epithelial and mucosal integrity, radiation exposure can alter gut commensal microbiota which may leave the host susceptible to opportunistic pathogens and serious sequelae such as sepsis. To mitigate the effects of hematopoietic ARS irradiation, currently approved treatments exist in the form of colony stimulating factors and antibiotics: however, there are few studies examining how these therapeutics affect GI-ARS and the gut microbiota. The aim of our study was to examine the longitudinal effects of Neulasta and/or ciprofloxacin treatment on the gut microbiota after exposure to 9.5 Gy 60Co gamma-radiation in mice. Methods: The gut microbiota of vehicle and drug-treated mice exposed to sham or gamma-radiation was characterized by shotgun sequencing with alpha diversity, beta diversity, and taxonomy analyzed on days 2, 4, 9, and 15 post-irradiation. Results: No significant alpha diversity differences were observed following radiation, while beta diversity shifts and taxonomic profiles revealed significant alterations in Akkermansia, Bacteroides, and Lactobacillus. Ciprofloxacin generally led to lower Shannon diversity and Bacteroides prevalence with increases in Akkermansia and Lactobacillus compared to vehicle treated and irradiated mice. While Neulasta increased Shannon diversity and by day 9 had more similar taxonomic profiles to sham than ciprofloxacin-or vehicle-treated irradiated animals. Combined therapy of Neulasta and ciprofloxacin induced a decrease in Shannon diversity and resulted in unique taxonomic profiles early post-irradiation, returning closer to vehicle-treated levels over time, but persistent increases in Akkermansia and Bacteroides compared to Neulasta alone. Discussion: This study provides a framework for the identification of microbial elements that may influence radiosensitivity, biodosimetry and the efficacy of potential therapeutics. Moreover, increased survival from H-ARS using these therapeutics may affect the symptoms and appearance of what may have been subclinical GI-ARS.


Assuntos
Ciprofloxacina , Microbioma Gastrointestinal , Animais , Ciprofloxacina/farmacologia , Microbioma Gastrointestinal/efeitos dos fármacos , Microbioma Gastrointestinal/efeitos da radiação , Camundongos , Antibacterianos/farmacologia , Síndrome Aguda da Radiação/tratamento farmacológico , Raios gama , Masculino , Feminino
6.
BMC Med Res Methodol ; 24(1): 108, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38724903

RESUMO

OBJECTIVE: Systematic literature reviews (SLRs) are critical for life-science research. However, the manual selection and retrieval of relevant publications can be a time-consuming process. This study aims to (1) develop two disease-specific annotated corpora, one for human papillomavirus (HPV) associated diseases and the other for pneumococcal-associated pediatric diseases (PAPD), and (2) optimize machine- and deep-learning models to facilitate automation of the SLR abstract screening. METHODS: This study constructed two disease-specific SLR screening corpora for HPV and PAPD, which contained citation metadata and corresponding abstracts. Performance was evaluated using precision, recall, accuracy, and F1-score of multiple combinations of machine- and deep-learning algorithms and features such as keywords and MeSH terms. RESULTS AND CONCLUSIONS: The HPV corpus contained 1697 entries, with 538 relevant and 1159 irrelevant articles. The PAPD corpus included 2865 entries, with 711 relevant and 2154 irrelevant articles. Adding additional features beyond title and abstract improved the performance (measured in Accuracy) of machine learning models by 3% for HPV corpus and 2% for PAPD corpus. Transformer-based deep learning models that consistently outperformed conventional machine learning algorithms, highlighting the strength of domain-specific pre-trained language models for SLR abstract screening. This study provides a foundation for the development of more intelligent SLR systems.


Assuntos
Aprendizado de Máquina , Infecções por Papillomavirus , Humanos , Infecções por Papillomavirus/diagnóstico , Economia Médica , Algoritmos , Avaliação de Resultados em Cuidados de Saúde/métodos , Aprendizado Profundo , Indexação e Redação de Resumos/métodos
7.
Fitoterapia ; 176: 105984, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38701870

RESUMO

A phytochemical study of the ethanol extract from Ailanthus altissima (Mill.) Swingle leaves resulted in the isolation of four new monoterpenoids (1-3, 5). The structures were elucidated using HRESIMS data, NMR spectroscopic data, quantum chemical calculations for NMR and ECD, and custom DP4+ probability analysis. Additionally, the absolute configuration of sugar was determined by acid hydrolysis. Compounds 1-4 are cyclogeraniane monocyclic monoterpenes, while compound 5 contains an acyclic mycrane monoterpenes skeleton. Anti-tyrosinase, anti-acetylcholinesterase, and anti-butyrylcholinesterase activities were tested. Compound 1 showed notable anti-acetylcholinesterase activity, and compound 3 exhibited significant inhibitory effects on anti-tyrosinase activity. Furthermore, the potential binding sites of compounds 1 and 3 were predicted by molecular docking.


Assuntos
Ailanthus , Simulação de Acoplamento Molecular , Monoterpenos , Compostos Fitoquímicos , Folhas de Planta , Ailanthus/química , Estrutura Molecular , Monoterpenos/isolamento & purificação , Monoterpenos/farmacologia , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Folhas de Planta/química , Inibidores da Colinesterase/isolamento & purificação , Inibidores da Colinesterase/farmacologia , Inibidores da Colinesterase/química , Monofenol Mono-Oxigenase/antagonistas & inibidores , Acetilcolinesterase/metabolismo , Butirilcolinesterase/metabolismo
8.
J Org Chem ; 89(12): 8326-8333, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38817078

RESUMO

Here, we present a straightforward α-trans-selective hydroboration of alkynyl sulfones with NHC-boranes without the need for a catalyst. This reaction is compatible with a wide range of substrates for efficiently producing structurally diverse α-borylated vinyl sulfones in satisfactory yields. The hydride transfer from NHC-borane 2a to alkynyl triflone 1b is studied by density functional theory (DFT) calculations for trans-hydroboration. Moreover, a regiodivergent deuterated semihydrogenation of alkynyl triflones has also been developed using D2O as the deuterium source. A variety of diversity-oriented D-containing vinyl triflones were prepared in good to excellent yields with excellent deuterium incorporation ratios. Synthetic manipulations of the deuterated products are achieved for the conversion into valuable deuterated molecules, indicating the utility of this protocol.

9.
Sci Rep ; 14(1): 7638, 2024 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-38561452

RESUMO

Hypomyelinating leukodystrophy (HLD) is a rare genetic heterogeneous disease that can affect myelin development in the central nervous system. This study aims to analyze the clinical phenotype and genetic function of a family with HLD-7 caused by POLR3A mutation. The proband (IV6) in this family mainly showed progressive cognitive decline, dentin dysplasia, and hypogonadotropic hypogonadism. Her three old brothers (IV1, IV2, and IV4) also had different degrees of ataxia, dystonia, or dysarthria besides the aforementioned manifestations. Their brain magnetic resonance imaging showed bilateral periventricular white matter atrophy, brain atrophy, and corpus callosum atrophy and thinning. The proband and her two living brothers (IV2 and IV4) were detected to carry a homozygous mutation of the POLR3A (NM_007055.4) gene c. 2300G > T (p.Cys767Phe), and her consanguineous married parents (III1 and III2) were p.Cys767Phe heterozygous carriers. In the constructed POLR3A wild-type and p.Cys767Phe mutant cells, it was seen that overexpression of wild-type POLR3A protein significantly enhanced Pol III transcription of 5S rRNA and tRNA Leu-CAA. However, although the mutant POLR3A protein overexpression was increased compared to the wild-type protein overexpression, it did not show the expected further enhancement of Pol III function. On the contrary, Pol III transcription function was frustrated (POLR3A, BC200, and tRNA Leu-CAA expression decreased), and MBP and 18S rRNA expressions were decreased. This study indicates that the POLR3A p.Cys767Phe variant caused increased expression of mutated POLR3A protein and abnormal expression of Pol III transcripts, and the mutant POLR3A protein function was abnormal.


Assuntos
Doenças Desmielinizantes Hereditárias do Sistema Nervoso Central , Masculino , Feminino , Humanos , Doenças Desmielinizantes Hereditárias do Sistema Nervoso Central/genética , Mutação , Fenótipo , Atrofia , RNA de Transferência , RNA Polimerase III/genética , RNA Polimerase III/metabolismo
10.
Sci Rep ; 14(1): 9534, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38664483

RESUMO

The IPv6 extension header mechanism, a new feature of the IPv6 protocol, enhances flexibility and scalability but introduces numerous security threats like firewall evasion and covert channels. Existing threat detection methods face limitations in detection types, universality, and speed. Hence, an adaptive detection model for IPv6 extension header threats (ADM-DDA6) is proposed. Firstly, standard rule sets are designed for common IPv6 extension headers, successfully detecting 70 types of threats from THC-IPv6 and ExtHdr tools using only 20 rules. Secondly, by parsing IPv6 extension headers, matching rules, establishing transition relationships, and deciding packet threat status based on final states (Normal or Abnormal), complex threats like header disorder and header repetition can be detected. Finally, an adaptive rule matching method is introduced, which dynamically selects rule sets based on IPv6 extension header types, effectively reducing rule matching time. Experimental results show that under different threat magnitudes, ADM-DDA6 is 32% faster than Suricata v6.0.12 and 21.2% faster than Snort v3.1.61.0 in detection speed. Additionally, as the number of threats increases, on commodity hardware, ADM-DDA6 incurs only a 0.7% increase in CPU overhead with no significant memory consumption increase, maintains maximum throughput, and exhibits minor performance changes under low and moderate network load conditions.

11.
Chem Commun (Camb) ; 60(34): 4577-4580, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38573313

RESUMO

The application of strain induces a transition in the ground-state magnetic configuration of Janus TiVC MXene from A-AFM to FM. A new system and method of solid-state disk information storage without electricity is developed based on the as-discovered reversible magnetic state transition in TiVC, which can achieve efficient storage of information in extremely harsh conditions.

12.
Comput Biol Chem ; 110: 108057, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38581840

RESUMO

Virtual screening-based molecular similarity and fingerprint are crucial in drug design, target prediction, and ADMET prediction, aiding in identifying potential hits and optimizing lead compounds. However, challenges such as lack of comprehensive open-source molecular fingerprint databases and efficient search methods for virtual screening are prevalent. To address these issues, we introduce FaissMolLib, an open-source virtual screening tool that integrates 2.8 million compounds from ChEMBL and ZINC databases. Notably, FaissMolLib employs the highly efficient Faiss search algorithm, outperforming the Tanimoto algorithm in identifying similar molecules with its tighter clustering in scatter plots and lower mean, standard deviation, and variance in key molecular properties. This feature enables FaissMolLib to screen 2.8 million compounds in just 0.05 seconds, offering researchers an efficient, easily deployable solution for virtual screening on laptops and building unique compound databases. This significant advancement holds great potential for accelerating drug discovery efforts and enhancing chemical data analysis. FaissMolLib is freely available at http://liuhaihan.gnway.cc:80. The code and dataset of FaissMolLib are freely available at https://github.com/Superhaihan/FiassMolLib.


Assuntos
Algoritmos , Ligantes , Avaliação Pré-Clínica de Medicamentos/métodos , Software , Bases de Dados de Compostos Químicos , Descoberta de Drogas , Estrutura Molecular
13.
Environ Pollut ; 349: 123926, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38580059

RESUMO

Ammonia (NH3) is attracting attention as a carbon-free energy source and a significant precursor to inorganic PM2.5 (hereafter PM2.5), aside from NOx and SOx. Since the emission of NH3 has often been overlooked compared to NOx and SOx, this study aims to reveal the role of NH3 and its emission control on PM2.5 in Kanto, Japan. With the aid of gas ratio (GR) quantitatively defining the stoichiometry between the three precursors to PM2.5, and the aid of atmospheric modeling software ADMER-PRO, coupled with thermodynamics calculations, the spatiotemporal distribution along with PM2.5 reduction under different NH3 emission cutoff strategies in Kanto had been revealed for the first time. The cutoff of NH3 emission could effectively reduce the PM2.5 concentration, with sources originated from agriculture, human/pet activities, and vehicle sources, overall giving a 93.32% PM2.5 reduction. Different cutoff strategies lead to distinct reduction efficiencies of the overall and local PM2.5 concentrations, with GR as a crucial factor. The regions with GR ∼1, are sensitive to the NH3 concentration for forming PM2.5, at which the NH3 reduction strategies should be applied with high priority. On the other hand, installing a new NH3 emission source should be avoided in the region with GR < 1, suppressing the so-yielded PM2.5 pollution. The future PM2.5 pollution control related to the NH3 emission control strategies based on GR, which is stoichiometry-based and applicable to regions other than Kanto, has been discussed.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Amônia , Monitoramento Ambiental , Material Particulado , Amônia/análise , Japão , Material Particulado/análise , Poluentes Atmosféricos/análise , Poluição do Ar/prevenção & controle , Poluição do Ar/estatística & dados numéricos , Monitoramento Ambiental/métodos
14.
Spectrochim Acta A Mol Biomol Spectrosc ; 316: 124316, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-38669982

RESUMO

Lysosomes, as crucial acidic organelles in cells, play a significant role in cellular functions. The levels and distribution of hypochlorous acid (HOCl) within lysosomes can profoundly impact their biological functionality. Hence, real-time monitoring of the concentration of HOCl in lysosomes holds paramount importance for further understanding various physiological and pathological processes associated with lysosomes. In this study, we developed a bodipy-based fluorescent probe derived from pyridine and phenyl selenide for the specific detection of HOCl in aqueous solutions. Leveraging the probe's sensitive photoinduced electron transfer effect from phenyl selenide to the fluorophore, the probe exhibited satisfactory high sensitivity (with a limit of detection of 5.2 nM and a response time of 15 s) to hypochlorous acid. Further biological experiments confirmed that the introduction of the pyridine moiety enabled the probe molecule to selectively target lysosomes. Moreover, the probe successfully facilitated real-time monitoring of HOCl in cell models stimulated by N-acetylcysteine (NAC) and lipopolysaccharide (LPS), as well as in a normal zebrafish model. This provides a universal method for dynamically sensing HOCl in lysosomes.


Assuntos
Corantes Fluorescentes , Ácido Hipocloroso , Lisossomos , Imagem Óptica , Peixe-Zebra , Ácido Hipocloroso/análise , Ácido Hipocloroso/metabolismo , Lisossomos/metabolismo , Lisossomos/química , Corantes Fluorescentes/química , Corantes Fluorescentes/síntese química , Animais , Humanos , Células RAW 264.7 , Camundongos , Compostos de Boro/química , Espectrometria de Fluorescência , Piridinas/química , Limite de Detecção
15.
Phytochemistry ; 222: 114067, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38583852

RESUMO

1,2-diarylpropanes are a kind of abundant natural products formed by radical coupling. On account of molecular flexibility, it was challenged in the identifications of relative and absolute configurations of the 1,2-diarylpropanes. In this research, fourteen pairs of enantiomeric 1,2-diarylpropanes (1a/1b-14a/14b), comprising twelve previously undescribed pairs (1a/1b-4a/4b, 6a/6b-10a/10b, and 12a/12b-14a/14b), were isolated from the fruit of Crataegus pinnatifida. Their structures were determined through multiple NMR spectral analyses, empirical NMR rules, X-ray crystallography, and the comparison of experimental ECD spectra with calculated data. In addition, the analysis of ECD spectra revealed that substituent effects could generate an inverted chiroptical response, exhibiting in mirror-image ECD signals. This phenomenon was investigated by conformational analysis, molecular orbital analysis, the transition density matrix and hole/electron distributions. Moreover, a potential experimental rule was proposed for the rapid determination of the absolute configurations of the 1,2-diarylpropanes.


Assuntos
Crataegus , Frutas , Crataegus/química , Frutas/química , Estrutura Molecular , Estereoisomerismo , Conformação Molecular , Cristalografia por Raios X , Dicroísmo Circular , Modelos Moleculares , Espectroscopia de Ressonância Magnética
16.
J Med Chem ; 67(9): 6952-6986, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38649304

RESUMO

The transcriptional coactivator cAMP response element binding protein (CREB)-binding protein (CBP) and its homologue p300 have emerged as attractive therapeutic targets for human cancers such as acute myeloid leukemia (AML). Herein, we report the design, synthesis, and biological evaluation of a series of cereblon (CRBN)-recruiting CBP/p300 proteolysis targeting chimeras (PROTACs) based on the inhibitor CCS1477. The representative compounds 14g (XYD190) and 14h (XYD198) potently inhibited the growth of AML cells with low nanomolar IC50 values and effectively degraded CBP and p300 proteins in a concentration- and time-dependent manner. Mechanistic studies confirmed that 14g and 14h can selectively bind to CBP/p300 bromodomains and induce CBP and p300 degradation in bromodomain family proteins in a CRBN- and proteasome-dependent manner. 14g and 14h displayed remarkable antitumor efficacy in the MV4;11 xenograft model (TGI = 88% and 93%, respectively). Our findings demonstrated that 14g and 14h are useful lead compounds and deserve further optimization and activity evaluation for the treatment of human cancers.


Assuntos
Antineoplásicos , Proteólise , Humanos , Antineoplásicos/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Animais , Camundongos , Proteólise/efeitos dos fármacos , Linhagem Celular Tumoral , Proteína p300 Associada a E1A/metabolismo , Proteína p300 Associada a E1A/antagonistas & inibidores , Proteína de Ligação a CREB/metabolismo , Proteína de Ligação a CREB/antagonistas & inibidores , Descoberta de Drogas , Ensaios Antitumorais Modelo de Xenoenxerto , Relação Estrutura-Atividade , Fatores de Transcrição de p300-CBP/metabolismo , Fatores de Transcrição de p300-CBP/antagonistas & inibidores , Proliferação de Células/efeitos dos fármacos , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/patologia , Camundongos Nus
17.
Bioorg Chem ; 147: 107335, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38583250

RESUMO

Fifty compounds including seven undescribed (1, 13, 18-20, 30, 31) and forty-three known (2-12, 14-17, 21-29, 32-50) ones were isolated from the extract of the twigs and leaves of Aglaia odorata with anti-neuroinflammatory activities. Their structures were determined by a combination of spectral analysis and calculated spectra (ECD and NMR). Among them, compounds 13-25 were found to possess tertiary amide bonds, with compounds 16, 17, and 19-21 existing detectable cis/trans mixtures in 1H NMR spectrum measured in CDCl3. Specifically, the analysis of the cis-trans isomerization equilibrium of tertiary amides in compounds 19-24 was conducted using NMR spectroscopy and quantum chemical calculations. Bioactivity evaluation showed that the cyclopenta[b]benzofuran derivatives (2-6, 8, 10, 12) could inhibit nitric oxide production at the nanomolar concentration (IC50 values ranging from 2 to 100 nM) in lipopolysaccharide-induced BV-2 cells, which were 413-20670 times greater than that of the positive drug (minocycline, IC50 = 41.34 µM). The cyclopenta[bc]benzopyran derivatives (13-16), diterpenoids (30-35), lignan (40), and flavonoids (45, 47, 49, 50) also demonstrated significant inhibitory activities with IC50 values ranging from 1.74 to 38.44 µM. Furthermore, the in vivo anti-neuroinflammatory effect of rocaglaol (12) was evaluated via immunofluorescence, qRT-PCR, and western blot assays in the LPS-treated mice model. The results showed that rocaglaol (12) attenuated the activation of microglia and decreased the mRNA expression of iNOS, TNF-α, IL-1ß, and IL-6 in the cortex and hippocampus of mice. The mechanistic study suggested that rocaglaol might inhibit the activation of the NF-κB signaling pathway to relieve the neuroinflammatory response.


Assuntos
Aglaia , Lipopolissacarídeos , Óxido Nítrico , Animais , Camundongos , Aglaia/química , Lipopolissacarídeos/antagonistas & inibidores , Lipopolissacarídeos/farmacologia , Óxido Nítrico/antagonistas & inibidores , Óxido Nítrico/biossíntese , Óxido Nítrico/metabolismo , Estrutura Molecular , Relação Estrutura-Atividade , Relação Dose-Resposta a Droga , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação , Masculino , Anti-Inflamatórios não Esteroides/farmacologia , Anti-Inflamatórios não Esteroides/química , Anti-Inflamatórios não Esteroides/isolamento & purificação , Benzofuranos/farmacologia , Benzofuranos/química , Benzofuranos/isolamento & purificação , Linhagem Celular , Folhas de Planta/química
18.
medRxiv ; 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38633810

RESUMO

Background: Large language models (LLMs) have shown promising performance in various healthcare domains, but their effectiveness in identifying specific clinical conditions in real medical records is less explored. This study evaluates LLMs for detecting signs of cognitive decline in real electronic health record (EHR) clinical notes, comparing their error profiles with traditional models. The insights gained will inform strategies for performance enhancement. Methods: This study, conducted at Mass General Brigham in Boston, MA, analyzed clinical notes from the four years prior to a 2019 diagnosis of mild cognitive impairment in patients aged 50 and older. We used a randomly annotated sample of 4,949 note sections, filtered with keywords related to cognitive functions, for model development. For testing, a random annotated sample of 1,996 note sections without keyword filtering was utilized. We developed prompts for two LLMs, Llama 2 and GPT-4, on HIPAA-compliant cloud-computing platforms using multiple approaches (e.g., both hard and soft prompting and error analysis-based instructions) to select the optimal LLM-based method. Baseline models included a hierarchical attention-based neural network and XGBoost. Subsequently, we constructed an ensemble of the three models using a majority vote approach. Results: GPT-4 demonstrated superior accuracy and efficiency compared to Llama 2, but did not outperform traditional models. The ensemble model outperformed the individual models, achieving a precision of 90.3%, a recall of 94.2%, and an F1-score of 92.2%. Notably, the ensemble model showed a significant improvement in precision, increasing from a range of 70%-79% to above 90%, compared to the best-performing single model. Error analysis revealed that 63 samples were incorrectly predicted by at least one model; however, only 2 cases (3.2%) were mutual errors across all models, indicating diverse error profiles among them. Conclusions: LLMs and traditional machine learning models trained using local EHR data exhibited diverse error profiles. The ensemble of these models was found to be complementary, enhancing diagnostic performance. Future research should investigate integrating LLMs with smaller, localized models and incorporating medical data and domain knowledge to enhance performance on specific tasks.

19.
Artigo em Inglês | MEDLINE | ID: mdl-38688300

RESUMO

Low-/negative-pressure hydrocephalus (LPH/NePH) is uncommon in clinical practice, and doctors are unfamiliar with it. LPH/NePH is frequently caused by other central nervous system diseases, and patients are frequently misdiagnosed with other types of hydrocephalus, resulting in delayed treatment. LPH/NePH therapy evolved to therapeutic measures based on "external ventricular drainage below atmospheric pressure" as the number of patients with LPH/NePH described in the literature has increased. However, the mechanism of LPH/NePH formation is unknown. Thus, understanding the process of LPH/NePH development is the most important step in improving diagnosis and treatment capability. Based on case reports of LPH/NePH, we reviewed theories of transcortical pressure difference, excessive cerebral venous drainage, brain viscoelastic changes, and porous elastic sponges.

20.
Front Pharmacol ; 15: 1315001, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38562460

RESUMO

Introduction: Due to the cardiotoxicity of pirarubicin (THP), it is necessary to investigate new compounds for the treatment of THP-induced cardiotoxicity. Isoquercitrin (IQC) is a natural flavonoid with anti-oxidant and anti-apoptosis properties. Thus, the present study aimed to investigate the influence of IQC on preventing the THP-induced cardiotoxicity in vivo and in vitro. Methods: The optimal concentration and time required for IQC to prevent THP-induced cardiomyocyte damage were determined by an MTT assay. The protective effect was further verified in H9c2 and HCM cells using dichlorodihydrofluorescein diacetate fluorescent probes, MitoTracker Red probe, enzyme-linked immunosorbent assay, JC-1 probe, and real time-quantitative polymerase chain reaction (RT-qPCR). Rats were administered THP to establish cardiotoxicity. An electrocardiogram (ECG) was performed, and cardiac hemodynamics, myocardial enzymes, oxidative stress indicators, and hematoxylin-eosin staining were studied. Voltage-dependent anion channel 1 (VDAC1), adenine nucleotide translocase 1 (ANT1), and cyclophilin D (CYPD) were detected by qRT-PCR, and the Phlpp1/AKT/Bcl-2 axis proteins were detected by western blot, confirming that IQC markedly increased cell viability and superoxide dismutase (SOD) levels, diminished the levels of ROS and MDA, and elevated mitochondrial function and apoptosis in vivo and in vitro. Results: Results showed that IQC reduced THP-induced myocardial histopathological injury, electrocardiogram (ECG) abnormalities, and cardiac dysfunction in vivo. IQC also decreased serum levels of MDA, BNP, CK-MB, c-TnT, and LDH, while increasing levels of SOD and GSH. We also found that IQC significantly reduced VDAC1, ANT1, and CYPD mRNA expression. In addition, IQC controlled apoptosis by modulating Phlpp1/AKT/Bcl-2 signaling pathways. IQC markedly increased H9c2 and HCM cell viability and SOD levels, diminished the levels of ROS and MDA, and elevated mitochondrial function in H9c2 and HCM cells to defend against THP-induced cardiomyocyte apoptosis in vitro. The AKT inhibitor IMQ demonstrated that IQC lacked antioxidant and anti-apoptotic properties. Moreover, our data showed that IQC regulates Phlpp1 expression, thereby influencing the expression levels of p-AKT, cytochrome c, caspase-3, caspase-9, Bcl-2, and Bax. Discussion: In conclusion, our results indicate that IQC protects the changes in mitochondrial membrane permeability in cardiomyocytes by regulating the Phlpp1/AKT/Bcl-2 signaling pathway, inhibits the release of cytc from the mitochondrial inner membrane to the cytoplasm, forms apoptotic bodies, induces cell apoptosis, and reduces THP induced cardiotoxicity.

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