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1.
Evol Comput ; : 1-31, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38776458

RESUMO

Premature convergence is a thorny problem for particle swarm optimization (PSO) algorithms, especially on multimodal problems, where maintaining swarm diversity is crucial. However, most enhancement strategies for PSO, including the existing diversity-guided strategies, have not fully addressed this issue. This paper proposes the virtual position guided (VPG) strategy for PSO algorithms. The VPG strategy calculates diversity values for two different populations and establishes a diversity baseline. It then dynamically guides the algorithm to conduct different search behaviors, through three phases - divergence, normal, and acceleration - in each iteration, based on the relationships among these diversity values and the baseline. Collectively, these phases orchestrate different schemes to balance exploration and exploitation, collaboratively steering the algorithm away from local optima and towards enhanced solution quality. The introduction of 'virtual position' caters to the strategy's adaptability across various PSO algorithms, ensuring the generality and effectiveness of the proposed VPG strategy. With a single hyperparameter and a recommended usual setup, VPG is easy to implement. The experimental results demonstrate that the VPG strategy is superior to several canonical and the state-of-the-art strategies for diversity guidance, and is effective in improving the search performance of most PSO algorithms on multimodal problems of various dimensionalities.

2.
J Biochem Mol Toxicol ; 38(5): e23714, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38629493

RESUMO

Parkinson's disease (PD) is a neurodegenerative disease featured by progressive loss of nigrostriatal dopaminergic neurons, the etiology of which is associated with the existence of neuroinflammatory response and oxidative stress. Vincamine is an indole alkaloid that was reported to exhibit potent anti-inflammatory and antioxidant properties in many central and/or peripheral diseases. Nevertheless, the specific role of vincamine in PD development remains unknown. In our study, dopaminergic neuron loss was determined through immunohistochemistry staining and western blot analysis of tyrosine hydroxylase (TH) expression in the substantia nigra (SN) of PD mice. Reactive oxygen species (ROS) production and malondialdehyde (MDA), superoxide dismutase (SOD), and glutathione (GSH) levels were detected through DHE staining and commercially available kits to assess oxidative stress. Pro-inflammatory cytokine (TNF-α, IL-1ß, and IL-6) levels in the SN were measured via RT-qPCR and western blot analysis. Microglial and astrocyte activation was examined through immunofluorescence staining of Iba-1 (microglia marker) and GFAP (astrocyte marker) in the SN. The regulation of vincamine on the NF-κB and Nrf2/HO-1 pathway was estimated through western blot analysis. Our results showed that vincamine treatment decreased TNF-α, IL-1ß, and IL-6 mRNA and protein levels, reduced GFAP and Iba-1 expression, decreased ROS production and MDA level, and increased SOD activity and GSH level in the SN of PD mice. Mechanically, vincamine repressed the phosphorylation levels of p65, IKKß, and IκBα but enhanced the protein levels of Nrf2 and HO-1 in PD mice. Collectively, vincamine plays a neuroprotective role in PD mouse models by alleviating neuroinflammation and oxidative damage via suppressing the NF-κB pathway and activating the Nrf2/HO-1 pathway.


Assuntos
Doença de Parkinson , Vincamina , Animais , Camundongos , Lesões Encefálicas , Interleucina-6/metabolismo , Doenças Neurodegenerativas , Doenças Neuroinflamatórias , Fator 2 Relacionado a NF-E2/metabolismo , NF-kappa B/metabolismo , Estresse Oxidativo , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/metabolismo , Espécies Reativas de Oxigênio , Transdução de Sinais , Superóxido Dismutase/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Vincamina/administração & dosagem
3.
BMC Neurol ; 24(1): 58, 2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38336633

RESUMO

BACKGROUND: Arterial transit artifact (ATA) observed on arterial spin labeling (ASL) was recently suggested to be associated with improved functional outcomes following acute ischemic stroke (AIS). AIS is a heterogeneous disease with diverse pathogenic mechanisms depending on the stroke subtype. This study aimed to investigate the association between ATA and 3-month functional outcomes in AIS patients according to etiology subtypes. METHODS: Consecutive patients with AIS were included. All patients underwent ASL MRI with postlabeling delay (PLD) of 1.5 and 2.5 s. ATA was assessed from the ASL images of both PLDs. Stroke etiologic subtypes were determined according to the modified TOAST (Trial of ORG 10172 in Acute Stroke Treatment) classification. Short-term functional outcomes were evaluated using the 3-month modified Rankin scale (mRS). Log-binomial regression was applied to analyze the association between ATA and functional outcomes at 3 months after stroke. RESULTS: Ninety-eight AIS patients (62.73 ± 13.05 years; 68 men) were finally included. ATA was detected in forty-six patients and most frequently seen in the large-artery atherosclerosis (LAA) subtype (35/46). The ATA group exhibited a lower percentage of patients with mRS > 2 compared to the group without ATA (36.5% vs. 19.6%; P < 0.001). ATA was independently associated with better 3-month clinical outcomes (adjusted risk ratio, 0.35[95% CI, 0.16-0.74]) in the multivariate log-binomial regression model. After stratification by TOAST subtypes, a significant association was found between ATA and better outcomes in the LAA subtype (adjusted risk ratio, 0.20[ 95% CI, 0.05-0.72]) but not in cardioembolism and small artery occlusion (SVO) subtype. CONCLUSION: ATA is associated with better outcomes at 3 months in patients with AIS, especially in the LAA subtype, but this association attenuated in the cardioembolism and SVO subtypes.


Assuntos
Aterosclerose , Isquemia Encefálica , AVC Isquêmico , Acidente Vascular Cerebral , Masculino , Humanos , Isquemia Encefálica/complicações , AVC Isquêmico/diagnóstico por imagem , AVC Isquêmico/complicações , Prognóstico , Artefatos , Acidente Vascular Cerebral/complicações , Aterosclerose/complicações , Artérias
4.
J Control Release ; 367: 148-157, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38228272

RESUMO

Antibody-drug conjugates (ADCs) are a rapidly expanding class of anticancer therapeutics, with 14 ADCs already approved worldwide. We developed unique linker technologies for the bioconjugation of drug molecules with controlled-release applications. We synthesized cathepsin-cleavable ADCs using a dimeric prodrug system based on a self-immolative dendritic scaffold, resulting in a high drug-antibody ratio (DAR) with the potential to reach 16 payloads due to its dendritic structure, increased stability in the circulation and efficient release profile of a highly cytotoxic payload at the targeted site. Using our novel cleavable linker technologies, we conjugated the anti-human epidermal growth factor receptor 2 (anti-HER2) antibody, trastuzumab, with topoisomerase I inhibitors, exatecan or belotecan. The newly synthesized ADCs were tested in vitro on mammary carcinoma cells overexpressing human HER2, demonstrating a substantial inhibitory effect on the proliferation of HER2-positive cells. Importantly, a single dose of our trastuzumab-based ADCs administered in vivo to mice bearing HER2-positive tumors, showed a dose-dependent inhibition of tumor growth and survival benefit, with the most potent antitumor effects observed at 10 mg/kg, which resulted in complete tumor regression and survival of 100% of the mice. Overall, our novel dendritic technologies using the protease-cleavable Val-Cit linker present an opportunity for the development of highly selective and potent controlled-released therapeutic payloads. This strategy could potentially lead to the development of novel and effective ADC technologies for patients diagnosed with HER2-positive cancers. Moreover, our proposed ADC linker technology can be implemented in additional medical conditions such as other malignancies as well as autoimmune diseases that overexpress targets, other than HER2.


Assuntos
Antineoplásicos , Imunoconjugados , Humanos , Camundongos , Animais , Inibidores da Topoisomerase I/uso terapêutico , Anticorpos Monoclonais Humanizados/química , Anticorpos Monoclonais Humanizados/farmacologia , Linhagem Celular Tumoral , Trastuzumab/química , Antineoplásicos/química , Receptor ErbB-2/metabolismo , Imunoconjugados/uso terapêutico , Imunoconjugados/química
5.
Org Biomol Chem ; 21(34): 6949-6955, 2023 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-37581482

RESUMO

Euphorlactone A (1), a rare rearranged ent-atisane norditerpenoid with an undescribed 3-nor-2,4-olide-ent-atisane scaffold, and euphorlactone B (2), a new ent-atisane diterpenoid with an unprecedented seven-membered lactone ring C, were isolated from the roots of Euphorbia fischeriana. Their planar structures with absolute configurations were extensively elucidated by analysis of 1D and 2D NMR data, electronic circular dichroism (ECD) calculations, Rh2(OCOCF3)4-induced ECD curves, and single-crystal X-ray diffraction. Euphorlactone A (ELA) showed a remarkable AChE (acetylcholinesterase) inhibitory activity (IC50 = 2.13 ± 0.06 µM and Ki = 0.058 µM), which was five times stronger than that of the positive control (rivastigmine, IC50 = 12.46 ± 0.82 µM), and further in vitro enzyme inhibition kinetic analysis and molecular docking studies were performed to investigate the AChE inhibitory mechanism.


Assuntos
Diterpenos , Euphorbia , Euphorbia/química , Simulação de Acoplamento Molecular , Acetilcolinesterase , Cinética , Diterpenos/química , Raízes de Plantas/química , Estrutura Molecular
6.
Bioorg Chem ; 139: 106727, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37451147

RESUMO

In this work, a series of 2-(trifluoromethyl)quinolin-4-amine derivatives were designed and synthesized through structural optimization strategy as a microtubule-targeted agents (MTAs) and their cytotoxicity activity against PC3, K562 and HeLa cell lines were evaluated. The half maximal inhibitory concentration (IC50) of 5e, 5f, and 5o suggested that their potency of anti-proliferative activities against HeLa cell lines were better than the combretastatin A-4. Compound 5e showed the higher anti-proliferative activity against PC3, K562 and HeLa in vitro with IC50 values of 0.49 µM, 0.08 µM and 0.01 µM, respectively. Further mechanism study indicated that the representative compound 5e was new class of tubulin inhibitors by EBI competition assay and tubulin polymerization assays, it is similar to colchicine. Immunofluorescence staining revealed that compound 5e apparently disrupted tubulin network in HeLa cells, and compound 5e arrested HeLa cells at the G2/M phase and induced cells apoptosis in a dose-dependent manner. Molecular docking results illustrated that the hydrogen bonds of represented compounds reinforced the interactions in the pocket of colchicine binding site. Preliminary results suggested that 5e deserves further research as a promising tubulin inhibitor for the development of anticancer agents.


Assuntos
Antineoplásicos , Tubulina (Proteína) , Humanos , Estrutura Molecular , Células HeLa , Relação Estrutura-Atividade , Tubulina (Proteína)/metabolismo , Simulação de Acoplamento Molecular , Polimerização , Proliferação de Células , Ensaios de Seleção de Medicamentos Antitumorais , Antineoplásicos/farmacologia , Antineoplásicos/química , Moduladores de Tubulina/farmacologia , Moduladores de Tubulina/química , Microtúbulos/metabolismo , Colchicina/metabolismo
7.
J Med Chem ; 66(12): 7813-7833, 2023 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-37291753

RESUMO

Inflammation contributes to the development of ovarian cancer, and chemoresistance is a principal obstacle in ovarian cancer treatment. Herein, we designed and synthesized a series of gold(I) complexes derived from NSAIDs or their analogues. Among them, complex B3 (Npx-Au) displayed higher antitumor activity than cisplatin and other gold(I) complexes. Npx-Au could induce oxidative stress and the damage-associated molecular patterns (DAMPs) process by the inhibition of TrxR activity. Mechanistic studies revealed that simultaneous downregulation of COX-2 and PD-L1 was observed after Npx-Au treatment. Interestingly, in vivo experiments demonstrated that Npx-Au treatment could stimulate the immune response via reducing the expression of PD-L1, inducing DC maturation and increasing the infiltration of T (CD4+ and CD8+) cells. Collectively, our studies found that the gold(I) complex Npx-Au could elicit immunogenic cell death (ICD) and provide a promising strategy for chemotherapy combined with immunotherapy in the treatment of ovarian cancer.


Assuntos
Antígeno B7-H1 , Neoplasias Ovarianas , Humanos , Feminino , Espécies Reativas de Oxigênio , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/patologia , Imunidade , Ouro , Inflamação/tratamento farmacológico , Linhagem Celular Tumoral
8.
Small ; 19(18): e2208227, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36732906

RESUMO

Peritumoral brain invasion is the main target to cure glioblastoma. Chemoradiotherapy and targeted therapies fail to combat peritumoral relapse. Brain inaccessibility and tumor heterogeneity explain this failure, combined with overlooking the peritumor microenvironment. Reduce graphene oxide (rGO) provides a unique opportunity to modulate the local brain microenvironment. Multimodal graphene impacts are reported on glioblastoma cells in vitro but fail when translated in vivo because of low diffusion. This issue is solved by developing a new rGO formulation involving ultramixing during the functionalization with polyethyleneimine (PEI) leading to the formation of highly water-stable rGO-PEI. Wide mice brain diffusion and biocompatibility are demonstrated. Using an invasive GL261 model, an anti-invasive effect is observed. A major unexpected modification of the peritumoral area is also observed with the neutralization of gliosis. In vitro, mechanistic investigations are performed using primary astrocytes and cytokine array. The result suggests that direct contact of rGO-PEIUT neutralizes astrogliosis, decreasing several proinflammatory cytokines that would explain a bystander tumor anti-invasive effect. rGO also significantly downregulates several proinvasive/protumoral cytokines at the tumor cell level. The results open the way to a new microenvironment anti-invasive nanotherapy using a new graphene nanomaterial that is optimized for in vivo brain delivery.


Assuntos
Glioblastoma , Grafite , Animais , Camundongos , Glioblastoma/terapia , Citocinas , Encéfalo , Microambiente Tumoral
9.
Nature ; 611(7937): 682-687, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36418450

RESUMO

The discovery of several electronic orders in kagome superconductors AV3Sb5 (A means K, Rb, Cs) provides a promising platform for exploring unprecedented emergent physics1-9. Under moderate pressure (<2.2 GPa), the triple-Q charge density wave (CDW) order is monotonically suppressed by pressure, while the superconductivity shows a two-dome-like behaviour, suggesting an unusual interplay between superconductivity and CDW order10,11. Given that time-reversal symmetry breaking and electronic nematicity have been revealed inside the triple-Q CDW phase8,9,12,13, understanding this CDW order and its interplay with superconductivity becomes one of the core questions in AV3Sb5 (refs. 3,5,6). Here, we report the evolution of CDW and superconductivity with pressure in CsV3Sb5 by 51V nuclear magnetic resonance measurements. An emergent CDW phase, ascribed to a possible stripe-like CDW order with a unidirectional 4a0 modulation, is observed between Pc1 ≅ 0.58 GPa and Pc2 ≅ 2.0 GPa, which explains the two-dome-like superconducting behaviour under pressure. Furthermore, the nuclear spin-lattice relaxation measurement reveals evidence for pressure-independent charge fluctuations above the CDW transition temperature and unconventional superconducting pairing above Pc2. Our results not only shed new light on the interplay of superconductivity and CDW, but also reveal new electronic correlation effects in kagome superconductors AV3Sb5.

10.
Int Immunopharmacol ; 110: 109034, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35834952

RESUMO

Hepatic fibrosis is an essential pathology of multiple chronicliverdiseases. The aim of this study was to investigate the role of miR-301a-3p in hepatic fibrosis. We found that miR-301a-3p was upregulated in hepatic fibrosis patients and in culture-activated human hepatic stellate cells (HSCs). Interestingly, miR-301a-3p expression was increased in hepatic fibrosis progression mice while decreased in hepatic fibrosis recovery mice, indicating that miR-301a-3p may participate in the hepatic fibrosis pathology. Functionally, the effects of miR-301a-3p both on hepatic fibrosis progression and regression were assessed in vivo. Inhibiting miR-301a-3p amelioratedmouse liver fibrogenesis and collagen deposition and suppressed HSC activation and fibrogenic factor expression. Whereas, in hepatic fibrosis regression, upregulating miR-301a-3p impaired mouse hepatic fibrosis recovery by inducing HSC activation and triggering inflammation. Consistently, gain-of-function and loss-of-function analysis of miR-301a-3p were performed to evaluate its effects on human HSCs LX-2 cell. We found that suppressing miR-301a-3p inhibited LX-2 cell activation and proliferation, and induced LX-2 cell apoptosis, accompaniedby decreased fibrotic mediators expression. Collectively, these findings suggest miR-301a-3p drives liver fibrogenesis and HSC activation in hepatic fibrosis. Mechanistically, we demonstrated miR-301a-3p binds directly to phosphatase and tensin homolog (PTEN) by luciferase reporter analysis, pull-down, and RIP assay. Indicating that miR-301a-3p plays a critical rolein promotingliverfibrogenesis viamodulating the PTEN/platelet derived growth factor ß (PDGFR-ß) pathway. In conclusion, our findings demonstrate that miR-301a-3p expression is closely correlated with hepatic fibrosis pathology, and that enhancing miR-301a-3p maintains the HSC profibrogenic phenotype, triggers inflammatoryresponses, promotes fibrogenic factor production, and further exacerbates liver fibrogenesis. These findings suggest that miR-301a-3p may serve as a promising diagnostic and prognosis biomarker for hepatic fibrosis treatment.


Assuntos
Células Estreladas do Fígado , MicroRNAs/metabolismo , Animais , Proliferação de Células , Células Estreladas do Fígado/patologia , Humanos , Cirrose Hepática/metabolismo , Camundongos , MicroRNAs/genética , PTEN Fosfo-Hidrolase/genética , PTEN Fosfo-Hidrolase/metabolismo , Proteínas Proto-Oncogênicas c-sis/farmacologia , Transdução de Sinais
11.
Nanomaterials (Basel) ; 12(11)2022 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-35683757

RESUMO

Mercury, as one type of toxic heavy metal, represents a great threat to environmental and biological metabolic systems. Thus, reliable and sensitive quantitative detection of mercury levels is particularly meaningful for environmental protection and human health. We proposed a high-throughput single-particle color imaging strategy under dark-field microscopy (DFM) for mercury ions (Hg2+) detection by using individual concave cube Au nanoparticles as optical probes. In the presence of ascorbic acid (AA), Hg2+ was reduced to Hg which forms Au-Hg amalgamate with Au nanoparticles, altering their localized surface plasmon resonance (LSPR). Transmission electron microscopy (TEM) images demonstrated that the concave cube Au nanoparticles were approaching to sphere upon increasing the concentration of Hg2+. The nanoparticles underwent an obvious color change from red to yellow, green, and finally blue under DFM due to the shape-evolution and LSPR changes. In addition, we demonstrated for the first time that the LSPR of Au-Hg amalgamated below 400 nm. Inspired by the above-mentioned results, single-particle color variations were digitalized by converting the color image into RGB channels to obtain (green+blue)/red intensity ratios [(G+B)/R]. The concentration-dependence change was quantified by statistically analyzing the (G+B)/R ratios of a large number of particles. A linear range from 10 to 2000 nM (R2 = 0.972) and a limit of detection (LOD) of 1.857 nM were acquired. Furthermore, many other metal ions, like Cu2+, Cr3+, etc., did not interfere with Hg2+ detection. More importantly, Hg2+ content in industrial wastewater samples and in the inner regions of human HepG2 cells was determined, showing great potential for developing a single-particle color imaging sensor in complex biological samples using concave cube Au nanoparticles as optical probes.

12.
Chem Soc Rev ; 51(13): 5518-5556, 2022 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-35699475

RESUMO

Metal complexes have demonstrated significant antitumor activities and platinum complexes are well established in the clinical application of cancer chemotherapy. However, the platinum-based treatment of different types of cancers is massively hampered by severe side effects and resistance development. Consequently, the development of novel metal-based drugs with different mechanism of action and pharmaceutical profile attracts modern medicinal chemists to design and synthesize novel metal-based agents. Among non-platinum anticancer drugs, gold complexes have gained considerable attention due to their significant antiproliferative potency and efficacy. In most situations, the gold complexes exhibit anticancer activities by targeting thioredoxin reductase (TrxR) or other thiol-rich proteins and enzymes and trigger cell death via reactive oxygen species (ROS). Interestingly, gold complexes were recently reported to elicit biochemical hallmarks of immunogenic cell death (ICD) as an ICD inducer. In this review, the recent progress of gold(I) and gold(III) complexes is comprehensively summarized, and their activities and mechanism of action are documented.


Assuntos
Antineoplásicos , Complexos de Coordenação , Neoplasias , Antineoplásicos/química , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Complexos de Coordenação/química , Complexos de Coordenação/farmacologia , Complexos de Coordenação/uso terapêutico , Ouro/química , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Tiorredoxina Dissulfeto Redutase/metabolismo
13.
Innate Immun ; 28(5): 155-163, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35548957

RESUMO

Th17 cells represent important immune cells. Ursolic acid (UA) can regulate immune cell activities. This study was aimed to explore the effects of UA on Th17 cell differentiation and Schwann cell(SCs)-mediated migration and the potential mechanism. Naïve CD4+ T cells were isolated from rat peripheral blood, induced for Th17 cell differentiation, and treated with UA. The proportion of Th17 cells was detected by flow cytometry assay. SCs were co-cultured with Th17 cells. Th17 cell migration was detected by Transwell assay. The molecule expression was determined by Western blot and qRT-PCR. UA inhibited the Th17 cell differentiation and suppressed the STAT3/RORγt pathway. STAT3 overexpression up-regulated p-STAT3 and RORγt expression and promoted Th17 cell differentiation under the UA treatment. In LPS- and IFN-γ-stimulated-SCs, UA suppressed the expression of chemokines CXCL9/10, but had no significant effect of CCL20 expression. The expression CXCL9/10 receptor CXCR3 was higher in Th17 cells than that in Treg cells, while the expression CCL20 receptor CCR6 was lower in Th17 cells than that in Treg cells. UA, anti-CXCR3, and anti-CCR6 treatment inhibited SCs-mediated Th17 cell migration, and anti-CXCR3 exerted stronger inhibitory effect than Anti-CCR6. UA inhibited Th17 cell differentiation through STAT3/RORγt pathway and suppressed Th17 cell migration through down-regulating CXCL9/10 expression in SCs.


Assuntos
Quimiocina CXCL10 , Quimiocina CXCL9 , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares , Fator de Transcrição STAT3 , Células de Schwann , Células Th17 , Triterpenos , Animais , Diferenciação Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Quimiocina CXCL10/biossíntese , Quimiocina CXCL10/metabolismo , Quimiocina CXCL9/biossíntese , Quimiocina CXCL9/metabolismo , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/metabolismo , Ratos , Fator de Transcrição STAT3/metabolismo , Células de Schwann/citologia , Células de Schwann/efeitos dos fármacos , Células de Schwann/metabolismo , Células Th17/citologia , Células Th17/efeitos dos fármacos , Células Th17/metabolismo , Triterpenos/farmacologia , Ácido Ursólico
14.
J Biomed Sci ; 29(1): 29, 2022 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-35534851

RESUMO

BACKGROUND: Castration-resistant prostate cancer (CRPC) with sustained androgen receptor (AR) signaling remains a critical clinical challenge, despite androgen depletion therapy. The Jumonji C-containing histone lysine demethylase family 4 (KDM4) members, KDM4A‒KDM4C, serve as critical coactivators of AR to promote tumor growth in prostate cancer and are candidate therapeutic targets to overcome AR mutations/alterations-mediated resistance in CRPC. METHODS: In this study, using a structure-based approach, we identified a natural product, myricetin, able to block the demethylation of histone 3 lysine 9 trimethylation by KDM4 members and evaluated its effects on CRPC. A structure-based screening was employed to search for a natural product that inhibited KDM4B. Inhibition kinetics of myricetin was determined. The cytotoxic effect of myricetin on various prostate cancer cells was evaluated. The combined effect of myricetin with enzalutamide, a second-generation AR inhibitor toward C4-2B, a CRPC cell line, was assessed. To improve bioavailability, myricetin encapsulated by poly lactic-co-glycolic acid (PLGA), the US food and drug administration (FDA)-approved material as drug carriers, was synthesized and its antitumor activity alone or with enzalutamide was evaluated using in vivo C4-2B xenografts. RESULTS: Myricetin was identified as a potent α-ketoglutarate-type inhibitor that blocks the demethylation activity by KDM4s and significantly reduced the proliferation of both androgen-dependent (LNCaP) and androgen-independent CRPC (CWR22Rv1 and C4-2B). A synergistic cytotoxic effect toward C4-2B was detected for the combination of myricetin and enzalutamide. PLGA-myricetin, enzalutamide, and the combined treatment showed significantly greater antitumor activity than that of the control group in the C4-2B xenograft model. Tumor growth was significantly lower for the combination treatment than for enzalutamide or myricetin treatment alone. CONCLUSIONS: These results suggest that myricetin is a pan-KDM4 inhibitor and exhibited potent cell cytotoxicity toward CRPC cells. Importantly, the combination of PLGA-encapsulated myricetin with enzalutamide is potentially effective for CRPC.


Assuntos
Antineoplásicos , Produtos Biológicos , Flavonoides , Neoplasias de Próstata Resistentes à Castração , Androgênios/farmacologia , Androgênios/uso terapêutico , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Produtos Biológicos/farmacologia , Produtos Biológicos/uso terapêutico , Linhagem Celular Tumoral , Proliferação de Células , Resistencia a Medicamentos Antineoplásicos , Flavonoides/farmacologia , Glicolatos , Glicóis/farmacologia , Glicóis/uso terapêutico , Humanos , Histona Desmetilases com o Domínio Jumonji/genética , Histona Desmetilases com o Domínio Jumonji/farmacologia , Masculino , Nitrilas/farmacologia , Nitrilas/uso terapêutico , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Neoplasias de Próstata Resistentes à Castração/genética , Neoplasias de Próstata Resistentes à Castração/metabolismo , Receptores Androgênicos/genética , Receptores Androgênicos/metabolismo , Receptores Androgênicos/uso terapêutico
15.
Nature ; 604(7904): 59-64, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35139530

RESUMO

Electronic nematicity, in which rotational symmetry is spontaneously broken by electronic degrees of freedom, has been demonstrated as a ubiquitous phenomenon in correlated quantum fluids including high-temperature superconductors and quantum Hall systems1,2. Notably, the electronic nematicity in high-temperature superconductors exhibits an intriguing entanglement with superconductivity, generating complicated superconducting pairing and intertwined electronic orders. Recently, an unusual competition between superconductivity and a charge-density-wave (CDW) order has been found in the AV3Sb5 (A = K, Rb, Cs) family with two-dimensional vanadium kagome nets3-8. Whether these phenomena involve electronic nematicity is still unknown. Here we report evidence for the existence of electronic nematicity in CsV3Sb5, using a combination of elastoresistance measurements, nuclear magnetic resonance (NMR) and scanning tunnelling microscopy/spectroscopy (STM/S). The temperature-dependent elastoresistance coefficient (m11 minus m12) and NMR spectra demonstrate that, besides a C2 structural distortion of the 2a0 × 2a0 supercell owing to out-of-plane modulation, considerable nematic fluctuations emerge immediately below the CDW transition (approximately 94 kelvin) and finally a nematic transition occurs below about 35 kelvin. The STM experiment directly visualizes the C2-structure-pinned long-range nematic order below the nematic transition temperature, suggesting a novel nematicity described by a three-state Potts model. Our findings indicate an intrinsic electronic nematicity in the normal state of CsV3Sb5, which sets a new paradigm for revealing the role of electronic nematicity on pairing mechanism in unconventional superconductors.

16.
Bioinformatics ; 37(21): 3715-3722, 2021 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-34478501

RESUMO

MOTIVATION: Precise prediction of cancer subtypes is of significant importance in cancer diagnosis and treatment. Disease etiology is complicated existing at different omics levels; hence integrative analysis provides a very effective way to improve our understanding of cancer. RESULTS: We propose a novel computational framework, named Deep Subspace Mutual Learning (DSML). DSML has the capability to simultaneously learn the subspace structures in each available omics data and in overall multi-omics data by adopting deep neural networks, which thereby facilitates the subtype's prediction via clustering on multi-level, single-level and partial-level omics data. Extensive experiments are performed in five different cancers on three levels of omics data from The Cancer Genome Atlas. The experimental analysis demonstrates that DSML delivers comparable or even better results than many state-of-the-art integrative methods. AVAILABILITY AND IMPLEMENTATION: An implementation and documentation of the DSML is publicly available at https://github.com/polytechnicXTT/Deep-Subspace-Mutual-Learning.git.


Assuntos
Neoplasias , Humanos , Neoplasias/genética , Redes Neurais de Computação , Genoma , Análise por Conglomerados , Multiômica
17.
Respirol Case Rep ; 9(3): e00718, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33614038

RESUMO

Ortner syndrome or cardiovocal syndrome is hoarseness of voice due to left recurrent laryngeal nerve palsy as a result of cardiovascular abnormality. It is not known that pneumothorax has any association with Ortner syndrome. A 56-year-old gentleman, with previous history of 20 pack-year smoking and 1-year history of hypertension, presented to us with cough for two weeks with intermittent haemoptysis, as well as hoarseness of voice for the past one year. Direct laryngoscopy confirmed that he had left vocal cord palsy. Clinical and radiological investigations suggested that he had left pneumothorax. Left chest tube thoracostomy was performed and computed tomography of chest revealed aortic isthmus aneurysm with dissection extending to distal left common iliac artery and residual left hydropneumothorax. The patient was then referred to the vascular team and cardiothoracic team for further management.

18.
PLoS One ; 16(1): e0245620, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33449946

RESUMO

Digoxin is commonly prescribed for heart failure and atrial fibrillation, but there is limited data on its safety in patients with chronic kidney disease (CKD). We conducted a population-based cohort study using the pre-end stage renal disease (ESRD) care program registry and the National Health Insurance Research Database in Taiwan. Of advanced CKD patient cohort (N = 31,933), we identified the digoxin user group (N = 400) matched with age and sex non-user group (N = 2,220). Multivariable Cox proportional hazards and sub-distribution hazards models were used to evaluate the association between digoxin use and the risk of death, cardiovascular events (acute coronary syndrome, ischemic stroke, or hemorrhagic stroke) and renal outcomes (ESRD, rapid decline in estimated glomerular filtration rate-eGFR, or acute kidney injury). Results showed that all-cause mortality was higher in the digoxin user group than in the non-user group, after adjusting for covariates (adjusted hazard ratio, aHR 1.63; 95% CI 1.23-2.17). The risk for acute coronary syndrome (sub-distribution hazard ratio, sHR 1.18; 95% CI 0.75-1.86), ischemic stroke (sHR 1.42; 95% CI 0.85-2.37), and rapid eGFR decline (sHR 1.00 95% CI 0.78-1.27) was not significantly different between two groups. In conclusion, our study demonstrated that digoxin use was associated with increased mortality, but not cardiovascular events or renal function decline in advanced CKD patients. This finding warns the safety of prescribing digoxin in this population. Future prospective studies are needed to overcome the limitations of cohort study design.


Assuntos
Injúria Renal Aguda , Doenças Cardiovasculares , Digoxina , Insuficiência Renal Crônica , Injúria Renal Aguda/induzido quimicamente , Injúria Renal Aguda/mortalidade , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Doenças Cardiovasculares/induzido quimicamente , Doenças Cardiovasculares/mortalidade , Digoxina/administração & dosagem , Digoxina/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Insuficiência Renal Crônica/tratamento farmacológico , Insuficiência Renal Crônica/mortalidade , Taiwan/epidemiologia
19.
J Econ Entomol ; 113(3): 1389-1398, 2020 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-32221516

RESUMO

Insecticide resistance in the German cockroach, Blattella germanica (L.), is a significant challenge to the pest management professionals worldwide. We collected 24 field populations of B. germanica from different localities in Taiwan island, reared them for one to two generations, and evaluated them for their resistance to deltamethrin, propoxur, and fipronil using the surface-contact method. Results showed that deltamethrin resistance ratio ranged from 1.5 to 817.5×. Among the strains, TC Supermarket, TC Sanshang Logistics, TC THSR, and TC 1Taichungsteak strains showed very high resistance to deltamethrin, which mortality ranged between 0 and 33% at 7-d post-treatment. On the other hand, resistance to propoxur and fipronil RR were 0.70-7.13× and 1.67-3.72×, respectively. Synergism studies using piperonyl butoxide (PBO) and S,S,S-tributylphosphorotrithioate (DEF) suggested the major involvement of cytochrome P450 monooxygenase and minor involvement of esterases. However, deltamethrin resistance in two strains (i.e., TC Supermarket and TC THSR) was not affected by both PBO and DEF, indicating that other mechanisms are involved in the resistance, including kdr resistance. Evaluation of the field strains using commercial gel baits containing fipronil, imidacloprid, hydramethylnon, and indoxacarb for up to 7 d resulted in 24.4-100%, 11.3-78.5%, 15.8-75.5%, and 63.3-100% mortality, respectively. We found that high deltamethrin resistance in some strains could affect the performance of fipronil, imidacloprid, and indoxacarb baits, indicating the potential involvement of cytochrome P450 monooxygenase in reducing the effectiveness of the bait toxicants.


Assuntos
Blattellidae , Baratas , Inseticidas , Animais , Resistência a Inseticidas , Inseticidas/farmacologia , Butóxido de Piperonila , Taiwan
20.
Vet Microbiol ; 240: 108548, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31902494

RESUMO

Based on its causing ever-increasing heavy economic losses, Riemerella anatipestifer has been viewed as an important bacterial pathogen in the duck industry worldwide. However, the molecular mechanisms regarding its pathogenicity are poorly understood. In our previous study, we have built a random mutagenesis library of Riemerella anatipestifer CH3 using transposon Tn4351. In this study, we screened the library by determining bacterial median lethal dose in ducklings. A mutant strain showed about 376-fold attenuated virulence in comparison with the wild-type strain CH3 was obtained. Subsequently, the Tn4351 inserted gene was identified as M949_RS00050, which encodes a putative protein containing an outer membrane protein beta-barrel domain by genome walking and sequence analyses. Southern blot analysis indicated a single Tn4351 insertion in the CH3 chromosomal DNA. Inactivation of M949_RS00050 gene did not affect bacterial metabolic activity and the silver stained lipopolysaccharide pattern. However, the bacterial sensitivity to normal duck sera killing and bacterial hydrophobicity were dramatically enhanced in the M949_RS00050 gene inactivated mutant strain, compared to its wild-type strain CH3. Moreover, bacterial adherence and invasion abilities, bacterial capsular polysaccharide quantity, biofilm formation capacity and the bacterial virulence of the mutant strain were obviously decreased, compared to the wild-type strain CH3. Thus, our finding demonstrates that the M949_RS00050 gene functions on multiple bacterial biological properties and virulence in Riemerella anatipestifer.


Assuntos
Aderência Bacteriana/genética , Infecções por Flavobacteriaceae/veterinária , Riemerella/genética , Riemerella/patogenicidade , Fatores de Virulência/genética , Animais , Atividade Bactericida do Sangue , Elementos de DNA Transponíveis/genética , Patos/microbiologia , Infecções por Flavobacteriaceae/microbiologia , Deleção de Genes , Biblioteca Gênica , Genes Bacterianos , Mutação , Doenças das Aves Domésticas/microbiologia
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