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1.
NAR Cancer ; 6(2): zcae028, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38915758

RESUMO

Somatic mutations are desirable targets for selective elimination of cancer, yet most are found within noncoding regions. We have adapted the CRISPR-Cas9 gene editing tool as a novel, cancer-specific killing strategy by targeting the subset of somatic mutations that create protospacer adjacent motifs (PAMs), which have evolutionally allowed bacterial cells to distinguish between self and non-self DNA for Cas9-induced double strand breaks. Whole genome sequencing (WGS) of paired tumor minus normal (T-N) samples from three pancreatic cancer patients (Panc480, Panc504, and Panc1002) showed an average of 417 somatic PAMs per tumor produced from single base substitutions. Further analyses of 591 paired T-N samples from The International Cancer Genome Consortium found medians of ∼455 somatic PAMs per tumor in pancreatic, ∼2800 in lung, and ∼3200 in esophageal cancer cohorts. Finally, we demonstrated 69-99% selective cell death of three targeted pancreatic cancer cell lines using 4-9 sgRNAs designed using the somatic PAM discovery approach. We also showed no off-target activity from these tumor-specific sgRNAs in either the patient's normal cells or an irrelevant cancer using WGS. This study demonstrates the potential of CRISPR-Cas9 as a novel and selective anti-cancer strategy, and supports the genetic targeting of adult cancers.

2.
Phys Rev Lett ; 132(21): 214001, 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38856244

RESUMO

The microscopic stress field inhomogeneity in the interfacial region adjacent to the liquid surface is the fundamental origin of the liquid surface tension, but because of broadening due to capillary fluctuations, a detailed molecular level understanding of the stress field remains elusive. In this work, we deconvolute the capillary fluctuations to reveal the intrinsic stress field and show that the atomic-level contributions to the surface tension are similar in functional form across a variety of monatomic systems. These contributions are confined to an interfacial region approximately 1.5±0.1 times the particle diameter for all systems studied. In addition, the intrinsic density and stress profiles show a strong spatial correlation that should be useful in the development of a statistical mechanical theory for the prediction of surface stress and surface tension.

3.
JMIR Med Inform ; 12: e54355, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38832581

RESUMO

Background: After strict COVID-19-related restrictions were lifted, health systems globally were overwhelmed. Much has been discussed about how health systems could better prepare for future pandemics; however, primary health care (PHC) has been largely ignored. Objective: We aimed to investigate what combined policies PHC could apply to strengthen the health care system via a bottom-up approach, so as to better respond to a public health emergency. Methods: We developed a system dynamics model to replicate Shanghai's response when COVID-19-related restrictions were lifted. We then simulated an alternative PHC-based integrated health system and tested the following three interventions: first contact in PHC with telemedicine services, recommendation to secondary care, and return to PHC for recovery. Results: The simulation results showed that each selected intervention could alleviate hospital overwhelm. Increasing the rate of first contact in PHC with telemedicine increased hospital bed availability by 6% to 12% and reduced the cumulative number of deaths by 35%. More precise recommendations had a limited impact on hospital overwhelm (<1%), but the simulation results showed that underrecommendation (rate: 80%) would result in a 19% increase in cumulative deaths. Increasing the rate of return to PHC from 5% to 20% improved hospital bed availability by 6% to 16% and reduced the cumulative number of deaths by 46%. Moreover, combining all 3 interventions had a multiplier effect; bed availability increased by 683%, and the cumulative number of deaths dropped by 75%. Conclusions: Rather than focusing on the allocation of medical resources in secondary care, we determined that an optimal PHC-based integrated strategy would be to have a 60% rate of first contact in PHC, a 110% recommendation rate, and a 20% rate of return to PHC. This could increase health system resilience during public health emergencies.

4.
Anal Chim Acta ; 1314: 342769, 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-38876513

RESUMO

Echinococcosis and tuberculosis are two common zoonotic diseases that can cause severe pulmonary infections. Early screening and treatment monitoring are of great significance, especially in areas with limited medical resources. Herein, we designed an operation-friendly and rapid magnetic enrichment-silver acetylene chromogenic immunoassay (Me-Sacia) to monitor the antibody. The main components included secondary antibody-modified magnetic nanoparticles (MNP-Ab2) as capture nanoparticles, specific peptide (EG95 or CFP10)-modified silver nanoparticles (AgNP-PTs) as detection nanoparticles, and alkyne-modified gold nanoflowers as chromogenic nanoparticles. Based on the magnetic separation and plasma luminescence techniques, Me-Sacia could completely replace the colorimetric assay of biological enzymes. It reduced the detection time to approximately 1 h and simplified the labor-intensive and equipment-intensive processes associated with conventional ELISA. Meanwhile, the Me-Sacia showed universality for various blood samples and intuitive observation with the naked eye. Compared to conventional ELISA, Me-Sacia lowered the detection limit by approximately 96.8 %, increased the overall speed by approximately 15 times, and improved sensitivity by approximately 7.2 %, with a 100 % specificity and a coefficient of variation (CV) of less than 15 %.


Assuntos
Equinococose , Tuberculose Pulmonar , Humanos , Animais , Tuberculose Pulmonar/diagnóstico , Equinococose/diagnóstico , Imunoensaio/métodos , Prata/química , Ouro/química , Nanopartículas Metálicas/química , Zoonoses/diagnóstico , Limite de Detecção
5.
J Environ Sci (China) ; 145: 1-12, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38844310

RESUMO

The potential association between colorectal cancer (CRC) and environmental pollutants is worrisome. Previous studies have found that some perfluoroalkyl acids, including perfluorooctane sulfonate (PFOS), induced colorectal tumors in experimental animals and promoted the migration of and invasion by CRC cells in vitro, but the underlying mechanism is unclear. Here, we investigated the effects of PFOS on the proliferation and migration of CRC cells and the potential mechanisms involving activating the PI3K/Akt-NF-κB signal pathway and epithelial-mesenchymal transition (EMT). It was found that PFOS promoted the growth and migration of HCT116 cells at non-cytotoxic concentrations and increased the mRNA expression of the migration-related angiogenic cytokines vascular endothelial growth factor (VEGF) and interleukin-8 (IL-8). In a mechanistic investigation, the up-stream signal pathway PI3K/Akt-NF-κB was activated by PFOS, and the process was suppressed by LY294002 (PI3K/Akt inhibitor) and BAY11-7082 (NF-κB inhibitor) respectively, leading to less proliferation of HCT116 cells. Furthermore, matrix metalloproteinases (MMP) and EMT-related markers were up-regulated after PFOS exposure, and were also suppressed respectively by LY294002 and BAY11-7082. Moreover, the up-regulation of EMT markers was suppressed by a MMP inhibitor GM6001. Taken together, our results indicated that PFOS promotes colorectal cancer cell migration and proliferation by activating the PI3K/Akt-NF-κB signal pathway and epithelial-mesenchymal transition. This could be a potential toxicological mechanism of PFOS-induced malignant development of colorectal cancer.


Assuntos
Ácidos Alcanossulfônicos , Movimento Celular , Neoplasias Colorretais , Transição Epitelial-Mesenquimal , Fluorocarbonos , Fluorocarbonos/toxicidade , Ácidos Alcanossulfônicos/toxicidade , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Neoplasias Colorretais/patologia , Humanos , Movimento Celular/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/metabolismo , Transdução de Sinais/efeitos dos fármacos , Poluentes Ambientais/toxicidade , Células HCT116 , Proteínas Proto-Oncogênicas c-akt/metabolismo , NF-kappa B/metabolismo , Proliferação de Células/efeitos dos fármacos , Linhagem Celular Tumoral
6.
Eur J Med Chem ; 275: 116609, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38896993

RESUMO

The overuse of antibiotics over an extended period has led to increasing antibiotic resistance in pathogenic bacteria, culminating in what is now considered a global health crisis. To tackle the escalating disaster caused by multidrug-resistant pathogens, the development of new bactericides with new action mechanism is highly necessary. In this study, using a biomimicking strategy, a series of new nonivamide derivatives that feature an isopropanolamine moiety [the structurally similar to the diffusible signal factor (DSF) of Xanthomonas spp.] were prepared for serving as potential quorum-sensing inhibitors (QSIs). After screening and investigation of their rationalizing structure-activity relationships (SARs), compound A26 was discovered as the most optimal active molecule, with EC50 values of 9.91 and 7.04 µg mL-1 against Xanthomonas oryzae pv oryzae (Xoo) and Xanthomonas axonopodis pv. citri (Xac). A docking study showed that compound A26 exhibited robust interactions with Glu A: 161 of RpfF, which was strongly evidenced by fluorescence titration assay (KA value for Xoo RpfF-A26 = 104.8709 M-1). Furthermore, various bioassays showed that compound A26 could inhibit various bacterial virulence factors, including biofilm formation, extracellular polysaccharides (EPS), extracellular enzyme activity, DSF production, and swimming motility. In addition, in vivo anti-Xoo results showed that compound A26 had excellent control efficiency (curative activity: 43.55 %; protective activity: 42.56 %), surpassing that of bismerthiazol and thiodiazole copper by approximately 8.0%-37.3 %. Overall, our findings highlight a new paradigm wherein nonivamide derivatives exhibit potential in combating pathogen resistance issues by inhibiting bacterial quorum sensing systems though attributing to their new molecular skeleton, novel mechanisms of action, and non-toxic features.

7.
BMC Gastroenterol ; 24(1): 209, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38902675

RESUMO

BACKGROUND: To compare the application of conventional MRI analysis and MRI-based radiomics to identify the circumferential resection margin (CRM) status of rectal cancer (RC). METHODS: A cohort of 301 RC patients with 66 CRM invloved status and 235 CRM non-involved status were enrolled in this retrospective study between September 2017 and August 2022. Conventional MRI characteristics included gender, age, diameter, distance to anus, MRI-based T/N phase, CEA, and CA 19 - 9, then the relevant logistic model (Logistic-cMRI) was built. MRI-based radiomics of rectal cancer and mesorectal fascia were calculated after volume of interest segmentation, and the logistic model of rectal cancer radiomics (Logistic-rcRadio) and mesorectal fascia radiomics (Logistic-mfRadio) were constructed. And the combined nomogram (nomo-cMRI/rcRadio/mfRadio) containing conventional MRI characteristics, radiomics of rectal cancer and mesorectal fascia was developed. The receiver operator characteristic curve (ROC) was delineated and the area under curve (AUC) was calculated the efficiency of models. RESULTS: The AUC of Logistic-cMRI was 0.864 (95%CI, 0.820 to 0.901). The AUC of Logistic-rcRadio was 0.883 (95%CI, 0.832 to 0.928) in the training set and 0.725 (95%CI, 0.616 to 0.826) in the testing set. The AUCs of Logistic-mfRadio was 0.891 (95%CI, 0.838 to 0.936) in the training set and 0.820 (95%CI, 0.725 to 0.905) in the testing set. The AUCs of nomo-cMRI/rcRadio/mfRadio were the highest in both the training set of 0.942 (95%CI, 0.901 to 0.969) and the testing set of 0.909 (95%CI, 0.830 to 0.959). CONCLUSION: MRI-based radiomics of rectal cancer and mesorectal fascia showed similar efficacy in predicting the CRM status of RC. The combined nomogram performed better in assessment.


Assuntos
Imageamento por Ressonância Magnética , Margens de Excisão , Neoplasias Retais , Humanos , Neoplasias Retais/diagnóstico por imagem , Neoplasias Retais/patologia , Neoplasias Retais/cirurgia , Imageamento por Ressonância Magnética/métodos , Masculino , Feminino , Estudos Retrospectivos , Pessoa de Meia-Idade , Idoso , Nomogramas , Curva ROC , Fáscia/diagnóstico por imagem , Fáscia/patologia , Reto/diagnóstico por imagem , Reto/patologia , Adulto , Modelos Logísticos , Área Sob a Curva , Radiômica
8.
Eur J Med Chem ; 275: 116558, 2024 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-38870833

RESUMO

The aberrant activation of FGFRs plays a critical role in various cancers, leading to the development of several FGFR inhibitors in clinic. However, the emergence of drug resistance, primarily due to gatekeeper mutations in FGFRs, has limited their clinical efficacy. To address the unmet medical need, a series of 5-amino-1H-pyrazole-4-carboxamide derivatives were designed and synthesized as novel pan-FGFR covalent inhibitors targeting both wild-type and the gatekeeper mutants. The representative compound 10h demonstrated nanomolar activities against FGFR1, FGFR2, FGFR3 and FGFR2 V564F gatekeeper mutant in biochemical assays (IC50 = 46, 41, 99, and 62 nM). Moreover, 10h also strongly suppressed the proliferation of NCI-H520 lung cancer cells, SNU-16 and KATO III gastric cancer cells with IC50 values of 19, 59, and 73 nM, respectively. Further X-ray co-crystal structure revealed that 10h irreversibly binds to FGFR1. The study provides a new promising point for anticancer drug development medicated by FGFRs.

9.
iScience ; 27(6): 110042, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38883811

RESUMO

Chemical warfare agents (CWAs), epitomized by the notoriously used mustard gas (HD), represent a class of exceptionally toxic chemicals whose airborne removal is paramount for battlefield safety. This study integrates high-throughput computational screening (HTCS) with advanced machine learning (ML) techniques to investigate the efficacy of metal-organic frameworks (MOFs) in adsorbing and capturing trace amounts of HD present in the air. Our approach commenced with a comprehensive univariate analysis, scrutinizing the impact of six distinct descriptors on the adsorption efficiency of MOFs. This analysis elucidated a pronounced correlation between MOF density and the Henry coefficient in the effective capture of HD. Then, four ML algorithms were employed to train and predict the performance of MOFs. The Random Forest (RF) algorithm demonstrates strong model learning and good generalization, achieving the best prediction result of 98.3%. In a novel exploratory stride, we incorporated a 166-bit MACCS molecular fingerprinting (MF) to identify critical functional groups within adsorbents. From the top 100 MOFs analyzed, 22 optimal functional groups were identified. Leveraging these insights, we designed three innovative substructures, grounded in these key functional groups, to enhance HD adsorption efficiency. In this work, the combination of MF and ML could provide a new direction for efficient screening of MOFs for the capture of HD in the air. The outcomes of this study offer substantial potential to revolutionize the domain of CWA capture. This represents a significant stride toward developing practical solutions that enhance both environmental protection and battlefield security.

10.
bioRxiv ; 2024 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-38853864

RESUMO

KRAS is frequently mutated in cancer, contributing to 20% of all human cancer especially pancreatic, colorectal and lung cancer. Signaling of the constitutively active KRAS oncogenic mutants is mostly compartmentalized to proteolipid nanoclusters on the plasma membrane (PM). Signaling nanoclusters of many KRAS mutants selectively enrich phosphatidylserine (PS) lipids with unsaturated sn-2 acyl chains, but not the fully saturated PS species. Thus, remodeling PS acyl chains may suppress KRAS oncogenesis. Lysophosphatidylcholine acyltransferases (LPCATs) remodel sn-2 acyl chains of phospholipids, with LPCAT1 preferentially generating the fully saturated lipids. Here, we show that stable expression of LPCAT1 depletes major PS species with unsaturated sn-2 chains while decreasing minor phosphatidylcholine (PC) species with the corresponding acyl chains. LPCAT1 expression more effectively disrupts the nanoclustering of oncogenic GFP-KRASG12V, which is restored by acute addback of exogenous unsaturated PS. LPCAT1 expression compromises signaling and oncogenic activities of the KRAS-dependent pancreatic tumor lines. LPCAT1 expression sensitizes human pancreatic tumor MiaPaCa-2 cells to KRASG12C specific inhibitor, Sotorasib. Statistical analyses of patient data further reveal that pancreatic cancer patients with KRAS mutations express less LPCAT1. Higher LPCAT1 expression also improves survival probability of pancreatic and lung adenocarcinoma patients with KRAS mutations. Thus, PS acyl chain remodeling selectively suppresses KRAS oncogenesis.

11.
Proc Natl Acad Sci U S A ; 121(24): e2404668121, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38833473

RESUMO

Developing anticancer drugs with low side effects is an ongoing challenge. Immunogenic cell death (ICD) has received extensive attention as a potential synergistic modality for cancer immunotherapy. However, only a limited set of drugs or treatment modalities can trigger an ICD response and none of them have cytotoxic selectivity. This provides an incentive to explore strategies that might provide more effective ICD inducers free of adverse side effects. Here, we report a metal-based complex (Cu-1) that disrupts cellular redox homeostasis and effectively stimulates an antitumor immune response with high cytotoxic specificity. Upon entering tumor cells, this Cu(II) complex enhances the production of intracellular radical oxidative species while concurrently depleting glutathione (GSH). As the result of heightening cellular oxidative stress, Cu-1 gives rise to a relatively high cytotoxicity to cancer cells, whereas normal cells with low levels of GSH are relatively unaffected. The present Cu(II) complex initiates a potent ferroptosis-dependent ICD response and effectively inhibits in vivo tumor growth in an animal model (c57BL/6 mice challenged with colorectal cancer). This study presents a strategy to develop metal-based drugs that could synergistically potentiate cytotoxic selectivity and promote apoptosis-independent ICD responses through perturbations in redox homeostasis.


Assuntos
Cobre , Glutationa , Homeostase , Oxirredução , Animais , Camundongos , Humanos , Glutationa/metabolismo , Camundongos Endogâmicos C57BL , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Estresse Oxidativo/efeitos dos fármacos , Sinergismo Farmacológico , Morte Celular Imunogênica/efeitos dos fármacos , Complexos de Coordenação/farmacologia , Complexos de Coordenação/química , Ferroptose/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Neoplasias Colorretais/imunologia , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/patologia , Neoplasias Colorretais/metabolismo
12.
Chemosphere ; 361: 142526, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38851507

RESUMO

The DEnitrifying AMmonium OXidation (DEAMOX) has been proven to be a promising process treating contaminated surface water containing ammonia and nitrate, while the enrichment of the slow-growing anammox bacteria (AnAOB) remains a challenge. In this study, a novel polyurethane-adhesion vermiculite/tourmaline (VTP) modified carrier was developed to achieve effective enrichment of AnAOB. The results demonstrated that the VTP-1 (vermiculite: tourmaline = 1:1) system exhibited the greatest performance with the total nitrogen removal efficiency reaching 87.6% and anammox contributing 63% to nitrogen removal. Scanning electron microscope analysis revealed the superior biofilm structure of the VTP-1 carrier, providing attachment for AnAOB. The addition of VTP-1 promoted the secretion of EPS (extracellular polymeric substances) by microorganisms, which increased to 85.34 mg/g VSS, contributing to the aggregation of anammox cells. The favorable substrate microenvironment created by NH4+ adsorption and NO2- supply via partial denitrification process facilitated the growth of AnAOB. The relative abundance of Candidatus Brocadia and Thauera increased from 0.04% to 0.3%-1.03% and 2.06% in the VTP-1 system, respectively. This study sheds new light on the anammox biofilm formation and provides a valid approach to initiate the DEAMOX process for low nitrogen polluted water treatment.


Assuntos
Silicatos de Alumínio , Compostos de Amônio , Biofilmes , Desnitrificação , Oxirredução , Compostos de Amônio/química , Silicatos de Alumínio/química , Bactérias/metabolismo , Nitrogênio/química , Poluentes Químicos da Água , Amônia/química , Nitratos
13.
Environ Sci Technol ; 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38898774

RESUMO

Placental DNA methylation (DNAm) may be a potential mechanism underlying the effects of prenatal bisphenol analogues (BPs) exposure on reproductive health. Based on the Shanghai-Minhang Birth Cohort Study (S-MBCS), this study investigated associations of placental DNAm at reproduction-related genes with prenatal BPs exposure and children's digit ratios at age 4 using multiple linear regression models, and mediation analysis was further used to examine the mediating role of placental DNAm in the associations between prenatal BPs exposure and digit ratios among 345 mother-child pairs. Prenatal exposure to bisphenol A (BPA) was associated with hypermethylation at Protocadherin 8 (PCDH8), RBMX Like 2 (RBMXL2), and Sperm Acrosome Associated 1 (SPACA1), while bisphenol F (BPF) exposure was associated with higher methylation levels of Fibroblast Growth Factor 13 (FGF13). Consistent patterns were found in associations between higher DNAm at the 4 genes and increased digit ratios. Further mediation analysis showed that about 15% of the effect of BPF exposure on increased digit ratios was mediated by placental FGF13 methylation. In conclusion, the altered placental DNAm status might be a mediator underlying the feminizing effect of prenatal BPs exposure.

14.
Org Lett ; 26(22): 4672-4677, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38787765

RESUMO

Picrachinentins A-F (1-6, respectively), six novel cyclopeptide alkaloid-type burpitides (CPABs), were isolated and fully elucidated from the EtOH extract of the stems and leaves of Picrasma chinensis. Structurally, compounds 1-6 have a 14-membered paracyclophane ring system that was closed through an ether bond between the ß-hydroxy amino acid and tyrosine and modified with a 4,5-methylenedioxybenzoyloxy (MDBz, 3 and 5) or hexanoyl (Hexa, 1, 2, 4, and 6) group at the N-terminus. Interestingly, this is the first report on the isolation and characterization of CPABs from plants of the Simaroubaceae family. In addition, all compounds showed a neuroprotective effect against H2O2-damaged SH-SY5Y cells. Compound 1 was further investigated for its neuroprotective activities using a 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced Parkinson's disease animal model, and it dramatically improved MPTP-impaired motor behavioral performance. Biochemical analysis revealed compound 1 restored the tyrosine hydroxylase expression in the striatum of the MPTP-damaged mouse brain, which demonstrates its protective effect on dopaminergic neurons.


Assuntos
Alcaloides , Fármacos Neuroprotetores , Peptídeos Cíclicos , Picrasma , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/isolamento & purificação , Animais , Peptídeos Cíclicos/química , Peptídeos Cíclicos/farmacologia , Peptídeos Cíclicos/isolamento & purificação , Camundongos , Picrasma/química , Alcaloides/farmacologia , Alcaloides/química , Alcaloides/isolamento & purificação , Estrutura Molecular , Humanos , Peróxido de Hidrogênio/farmacologia , Peróxido de Hidrogênio/antagonistas & inibidores , Folhas de Planta/química , 1-Metil-4-Fenil-1,2,3,6-Tetra-Hidropiridina/farmacologia
15.
Org Lett ; 26(22): 4716-4720, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38802298

RESUMO

To realize strong donor-acceptor face-to-face stacking for efficient through-space charge transfer-type thermally activated delayed fluorescence, a conceptually new design strategy is proposed to couple flexible bridges with adequate rigidity via built-in intramolecular hydrogen bonds (IHBs). The resulting emitter ACE-CN has a planarized benzyl methyl ether bridge self-anchored by the C-H···O IHB and shows a high photoluminescence quantum efficiency of 93%. The solution- and vacuum-processed devices exhibited high external quantum efficiencies of 11.8% and 24.7%, respectively.

16.
Phytochemistry ; 224: 114140, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38750709

RESUMO

Eight previously undescribed cevanine-type steroidal alkaloids, cirrhosinones I-N and cirrhosinols A-B, along with five known analogs, were isolated from the bulbs of Fritillaria cirrhosa D. Don. Their structures were elucidated on the basis of comprehensive analysis of HRESIMS, 1D and 2D NMR spectroscopic data, and single-crystal X-ray diffraction analyses. All compounds revealed weak NO inhibitory activities in the LPS-stimulated NR8383 cells at the concentration of 20 µM, with inhibition ratios ranging from 5.1% to 14.3%.


Assuntos
Alcaloides , Fritillaria , Raízes de Plantas , Fritillaria/química , Raízes de Plantas/química , Estrutura Molecular , Alcaloides/química , Alcaloides/isolamento & purificação , Alcaloides/farmacologia , Cevanas/química , Cevanas/farmacologia , Cevanas/isolamento & purificação , Óxido Nítrico/antagonistas & inibidores , Óxido Nítrico/biossíntese , Lipopolissacarídeos/farmacologia , Lipopolissacarídeos/antagonistas & inibidores , Animais , Conformação Molecular , Cristalografia por Raios X , Linhagem Celular , Ratos , Esteroides/química , Esteroides/isolamento & purificação , Esteroides/farmacologia , Relação Dose-Resposta a Droga , Relação Estrutura-Atividade , Modelos Moleculares
17.
Research (Wash D C) ; 7: 0359, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38694199

RESUMO

Porous substrates act as open "interfacial reactors" during the synthesis of polyamide composite membranes via interfacial polymerization. However, achieving a thin and dense polyamide nanofilm with high permeance and selectivity is challenging when using a conventional substrate with uniform wettability. To overcome this limitation, we propose the use of Janus porous substrates as confined interfacial reactors to decouple the local monomer concentration from the total monomer amount during interfacial polymerization. By manipulating the location of the hydrophilic/hydrophobic interface in a Janus porous substrate, we can precisely control the monomer solution confined within the hydrophilic layer without compromising its concentration. The hydrophilic surface ensures the uniform distribution of monomers, preventing the formation of defects. By employing Janus substrates fabricated through single-sided deposition of polydopamine/polyethyleneimine, we significantly reduce the thickness of the polyamide nanofilms from 88.4 to 3.8 nm by decreasing the thickness of the hydrophilic layer. This reduction leads to a remarkable enhancement in water permeance from 7.2 to 52.0 l/m2·h·bar while still maintaining ~96% Na2SO4 rejection. The overall performance of this membrane surpasses that of most reported membranes, including state-of-the-art commercial products. The presented strategy is both simple and effective, bringing ultrapermeable polyamide nanofilms one step closer to practical separation applications.

18.
Biomater Sci ; 12(12): 3175-3192, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38742916

RESUMO

The tumor immunosuppressive microenvironment (TIME) and uncontrollable release of antigens can lower the efficacy of nanovaccine-based immunotherapy (NBI). Therefore, it is necessary to develop a new strategy for TIME reshaping and controllable release of antigens to improve the NBI efficacy. Herein, an acidity-responsive Schiff base-conjugated polyphenol-coordinated nanovaccine was constructed for the first time to realize bidirectional TIME reshaping and controllable release of antigens for activating T cells. In particular, an acidity-responsive tannic acid-ovalbumin (TA-OVA) nanoconjugate was prepared via a Schiff base reaction. FeIII was coordinated with TA-OVA to produce a FeIII-TA-OVA nanosystem, and 1-methyltryptophan (1-MT) as an indoleamine 2,3-dioxygenase inhibitor was loaded to form a polyphenol-coordinated nanovaccine. The coordination between FeIII and TA could cause photothermal ablation of primary tumors, and the acidity-triggered Schiff base dissociation of TA-OVA could controllably release OVA to realize lysosome escape, initiating the body's immune response. More importantly, oxidative stress generated by a tumor-specific Fenton reaction of Fe ions could promote the polarization of tumor-associated macrophages from the M2 to M1 phenotype, resulting in the upregulation of cytotoxic T cells and helper T cells. Meanwhile, 1-MT could downregulate immunosuppressive regulatory T cells. Overall, such skillful combination of bidirectional TIME reshaping and controllable antigen release into one coordination nanosystem could effectively enhance the NBI efficacy of tumors.


Assuntos
Imunoterapia , Ovalbumina , Polifenóis , Bases de Schiff , Taninos , Microambiente Tumoral , Animais , Microambiente Tumoral/efeitos dos fármacos , Ovalbumina/imunologia , Ovalbumina/química , Ovalbumina/administração & dosagem , Polifenóis/química , Polifenóis/farmacologia , Camundongos , Taninos/química , Taninos/farmacologia , Bases de Schiff/química , Concentração de Íons de Hidrogênio , Vacinas Anticâncer/química , Vacinas Anticâncer/imunologia , Vacinas Anticâncer/administração & dosagem , Triptofano/química , Triptofano/análogos & derivados , Nanoconjugados/química , Camundongos Endogâmicos C57BL , Nanopartículas/química , Linhagem Celular Tumoral , Compostos Férricos/química , Nanovacinas
19.
J Med Chem ; 67(10): 8099-8121, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38722799

RESUMO

Nicotinamide phosphoribosyltransferase (NAMPT) is an attractive therapeutic target for treating select cancers. There are two forms of NAMPT: intracellular NAMPT (iNAMPT, the rate-limiting enzyme in the mammalian NAD+ main synthetic pathway) and extracellular NAMPT (eNAMPT, a cytokine with protumorigenic function). Reported NAMPT inhibitors only inhibit iNAMPT and show potent activities in preclinical studies. Unfortunately, they failed to show efficacy due to futility and toxicity. We developed a series of FK866-based NAMPT-targeting PROTACs and identified LYP-8 as a potent and effective NAMPT degrader that simultaneously diminished iNAMPT and eNAMPT. Importantly, LYP-8 demonstrated superior efficacy and safety in mice when compared to the clinical candidate, FK866. This study highlights the importance and feasibility of applying PROTACs as a superior strategy for interfering with both the enzymatic function of NAMPT (iNAMPT) and nonenzymatic function of NAMPT (eNAMPT), which is difficult to achieve with conventional NAMPT inhibitors.


Assuntos
Acrilamidas , Desenho de Fármacos , Nicotinamida Fosforribosiltransferase , Piperidinas , Nicotinamida Fosforribosiltransferase/antagonistas & inibidores , Nicotinamida Fosforribosiltransferase/metabolismo , Acrilamidas/farmacologia , Acrilamidas/química , Acrilamidas/síntese química , Animais , Humanos , Piperidinas/farmacologia , Piperidinas/química , Camundongos , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/química , Citocinas/metabolismo , Linhagem Celular Tumoral , Relação Estrutura-Atividade , Antineoplásicos/farmacologia , Antineoplásicos/química
20.
PhytoKeys ; 242: 1-8, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38764934

RESUMO

In this study, we describe and illustrate a new species, Primulaweiliei L.S.Yang, Z.K.Wu & G.W.Hu, from the Shennongjia Forestry District, Hubei Province in Central China. It is morphologically assigned to Primulasect.Aleuritia based on its dwarf and hairless habit, long petiole, fruits longer than calyx and covered by farina on the scape. This new species is similar to P.gemmifera and P.munroisubsp.yargongensis in the same section, but it can be distinguished by its smaller calyxes, homostylous flowers, corolla tube throat without annular appendage and only 1-2 flowers in each inflorescence. Based on the assessment conducted according to the IUCN Red List criteria, we propose that P.weiliei be classified as a Critically Endangered (CR) species.

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