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1.
Dalton Trans ; 53(19): 8335-8346, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38666487

RESUMO

Vanadium-based oxides are considered potential cathode materials for aqueous zinc ion batteries (AZIBs) due to their distinctive layered (or tunnel) structure suitable for zinc ion storage. However, the structural instability and sluggish kinetics of vanadium-based oxides have limited their capacity and cycling stability for large-scale applications. To overcome these shortcomings, here a porous vanadium-based oxide doped with zinc ions and carbon with the molecular formula ZnV2O4@C (ZVO@C) as the cathode material is synthesized by the pyrolysis of a bimetallic MOF precursor containing Zn/V. This electrode demonstrates a remarkable specific capacity of 425 mA h g-1 at 0.5 A g-1 and excellent cycling stability with about 97% capacity retention after 1000 cycles at 10 A g-1. The excellent electrochemical performance of ZVO@C can be attributed to more reaction active sites and the faster reaction kinetics for zinc ion diffusion and storage brought about by the porous layered spinel-type tunnel structure with high surface area and massive mesoporosity, as well as the enhanced electron transport efficiency and more stable channel structure achieved from the doped conductive carbon. The reaction mechanism and structural evolution of the ZVO@C electrode are analyzed using X-ray diffraction and X-ray photoelectron spectroscopy, revealing the formation of a new phase of ZnxV2O5·nH2O during the first charge, which participates in reversible cycling together with ZVO@C during the charging and discharging processes. Moreover, the energy storage mechanism is revealed, in which zinc ions and hydrogen ions jointly participate in intercalation and extraction. The present study demonstrates that constructing composite vanadium-based oxides based on bimetallic organic frameworks as precursor templates is an effective strategy for the development of high-performance cathode materials for AZIBs.

2.
Fitoterapia ; 173: 105790, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38158160

RESUMO

Three new furano-lactones, asperilactones A-C (1-3), and two known compounds silvaticol (4) and violaceic acid (5) were isolated from an ethanol extract of Aspergillus nidulans, a fungus isolated from the Annelida Whitmania pigra Whitman (Haemopidae). Their structures were elucidated by a combination of spectroscopy, ECD calculations, comparing optical rotation values, and single-crystal X-ray diffraction analyses. Asperilactone A (1) represented the first example of furano-lactone with an unusual 2-thia-6-oxabicyclo[3.3.0]octane ring system. Asperilactones A and B showed weak toxicity against the HL-60 and RKO.


Assuntos
Aspergillus nidulans , Lactonas/química , Estrutura Molecular , Cristalografia por Raios X , Análise Espectral
3.
Clin Rheumatol ; 43(2): 645-655, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38097864

RESUMO

OBJECTIVE: The semaphorins are membrane or secreted proteins first identified in neural development. Semaphorin 4D (Sema4D) is the first family member found to have immune properties. We evaluated the potential of Sema4D as a marker for rheumatoid arthritis (RA) disease activity, singly and in combination with other known biomarkers including rheumatoid factor (RF) and C-reactive protein (CRP). METHODS: Three hundred and eleven RA patients were enrolled. The patients were divided into three groups based on their disease activity in 28 joints (DAS28): mild, moderate, and severe. The healthy group included 40 healthy individuals. SerumSema4D was measured by quantitative ELISA and the specificity and sensitivity of biomarkers were evaluated by generating a receiver operating characteristic (ROC) curve to analyze their diagnostic accuracy. RESULTS: Serum Sema4D levels in the moderate and severe RA groups were elevated significantly above those of the controls (P < 0.01), while levels in the mild RA and control groups did not differ significantly (P > 0.05). The Sema4D cutoff threshold was 15.7 ng/ml when the DAS28 was applied as a reference. Compared to the erythrocyte sedimentation rate (ESR and CRP, Sema4D had the highest specificity (96.8%) and area under the curve (0.80) for diagnosing RA activity. The highest specificity (100%) for the biomarker combinations was obtained when Sema4D was combined with CRP and anti-CCP, the combination of the Sema4D combined with ESR and anti-CCP had the highest sensitivity (99.35%). According to this result, a new model for jointly calculating RA activity of Sema4D,anti-CCP and CRP was constructed. Meanwhile another model is established by using the method of multivariate analysis.Model comparison results showed the the multiple regression algorithm method fitted the patients' disease activity better. CONCLUSION: The serum Sema 4D level effectively reflects moderate to severe RA activity. Sema4D levels can be used together with conventional RA biomarkers to increase the diagnostic power of RA activity. The multiple regression algorithm method is promising in disease activity calculation.


Assuntos
Antígenos CD , Artrite Reumatoide , Semaforinas , Humanos , Anticorpos Antiproteína Citrulinada , Biomarcadores , Proteína C-Reativa/metabolismo
4.
Acta Biomater ; 172: 260-271, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37806373

RESUMO

Removing excessively produced cytokines is of paramount significance in blood purification therapy for hypercytokinemia-associated diseases. In this study, we devised a conduit that is modified with nanobodies (Nb) and incorporates static mixers (Nb-SMC) to eliminate surplus cytokines from the bloodstream. The low-pressure-drop (LPD) static mixer, with each unit featuring two 90°-crossed blades, was strategically arranged in a tessellated pattern on the inner wall of the conduit to induce turbulent mixing effects during the flow of blood. This arrangement enhances mass transfer and molecular diffusion, thereby assisting in the identification and elimination of cytokines. By utilizing computational fluid dynamics (CFD) studies, the Nb-SMC was rationally designed and prepared, ensuring an optimal interval between two mixer units (H/G = 2.5). The resulting Nb-SMC exhibited a remarkable selective clearance of IL-17A, reaching up to 85 %. Additionally, the process of Nb immobilization could be adjusted to achieve the simultaneous removal of multiple cytokines from the bloodstream. Notably, our Nb-SMC displayed good blood compatibility without potential adverse effects on the composition of human blood. As the sole documented static mixer-integrated conduit capable of selectively eliminating cytokines at their physiological concentrations, it holds promise in the clinical potential for hypercytokinemia in high-risk patients. STATEMENT OF SIGNIFICANCE: High-efficient cytokines removal in critical care still remains a challenge. The conduit technique we proposed here is a brand-new strategy for cytokines removal in blood purification therapy. On the one hand, nanobody endows the conduit with specific recognition of cytokine, on the other hand, the build-in static mixer enhances the diffusion of antigenic cytokine to the ligand. The combination of these two has jointly achieved the efficient and specific removal of cytokine. This innovative material is the only reported artificial biomaterial capable of selectively eliminating multiple cytokines under conditions close to clinical practice. It has the potential to improve outcomes for patients with hypercytokinemia and reduce the risk of adverse events associated with current treatment modalities.


Assuntos
Citocinas , Hemoperfusão , Humanos , Hemoperfusão/métodos , Síndrome da Liberação de Citocina , Próteses e Implantes
5.
J Nat Prod ; 86(9): 2081-2090, 2023 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-37676247

RESUMO

Nine new ergosteroids (1-9) and seven known ones (10-16) were isolated from Talaromyces adpressus. Their structures and absolute configurations were determined by the interpretation of NMR spectroscopic data, HRESIMS, ECD calculations, and single-crystal X-ray diffraction analyses. Structurally, compound 1 was an ergosteroid with two epoxy and a 3α-OH group at ring A, while compounds 8 and 9 had a contracted ring A with a peroxy bridge between C-3 and C-9, which were reported for the first time. Compounds 2-6, 9, 11, and 15 displayed cytotoxic activities with IC50 values ranging from 0.4 to 32 µM, and compound 7 exhibited an immunosuppressive effect against LPS-induced B lymphocyte proliferation with an IC50 value of 8.6 µM. The structure-activity relationships of these compounds are briefly discussed.


Assuntos
Antineoplásicos , Talaromyces , Proliferação de Células , Cristalografia por Raios X
6.
Front Immunol ; 14: 1173187, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37744384

RESUMO

Objective: Although Leflunomide (LEF) is effective in treating rheumatoid arthritis (RA), there are still a considerable number of patients who respond poorly to LEF treatment. Till date, few LEF efficacy-predicting biomarkers have been identified. Herein, we explored and developed a DNA methylation-based predictive model for LEF-treated RA patient prognosis. Methods: Two hundred forty-five RA patients were prospectively enrolled from four participating study centers. A whole-genome DNA methylation profiling was conducted to identify LEF-related response signatures via comparison of 40 samples using Illumina 850k methylation arrays. Furthermore, differentially methylated positions (DMPs) were validated in the 245 RA patients using a targeted bisulfite sequencing assay. Lastly, prognostic models were developed, which included clinical characteristics and DMPs scores, for the prediction of LEF treatment response using machine learning algorithms. Results: We recognized a seven-DMP signature consisting of cg17330251, cg19814518, cg20124410, cg21109666, cg22572476, cg23403192, and cg24432675, which was effective in predicting RA patient's LEF response status. In the five machine learning algorithms, the support vector machine (SVM) algorithm provided the best predictive model, with the largest discriminative ability, accuracy, and stability. Lastly, the AUC of the complex model(the 7-DMP scores with the lymphocyte and the diagnostic age) was higher than the simple model (the seven-DMP signature, AUC:0.74 vs 0.73 in the test set). Conclusion: In conclusion, we constructed a prognostic model integrating a 7-DMP scores with the clinical patient profile to predict responses to LEF treatment. Our model will be able to effectively guide clinicians in determining whether a patient is LEF treatment sensitive or not.


Assuntos
Artrite Reumatoide , Metilação de DNA , Humanos , Leflunomida/uso terapêutico , Prognóstico , DNA , Artrite Reumatoide/diagnóstico , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/genética
7.
Dalton Trans ; 52(38): 13797-13807, 2023 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-37721207

RESUMO

At present, vanadium-based cathodes for aqueous zinc-ion batteries (AZIBs) are limited by their slow reaction kinetics, poor electrical conductivity, and low capacity retention. To overcome these problems, here, we design a layered porous Mn0.18V2O5@C as the cathode material for AZIBs using a manganese-containing metal-organic framework as a template through a simple solvothermal method. Such an electrode delivers an excellent specific capacity (380 mA h g-1 at 0.1 A g-1) accompanied by superior cycling stability (about 85% capacity retention for 2000 cycles at 6 A g-1). The excellent electrochemical performance of Mn0.18V2O5@C is ascribed to the improved interface activity including smooth zinc ion transport, abundant ion reaction active sites and accelerated charge transfer resulting from the coordination of the porous structure, doped conductive carbon, and the stable channel structure derived from the pillar effect of doping manganese ions, preventing a premature collapse of the electrode structure. It is also revealed by structural evolution analysis that the residual zinc ions also combine with the original Mn0.18V2O5 to form a ZnxMnyV2O5 phase, which serves as an additional structural pillar and in the meantime, also participates in the following cycles. These favorable electrochemical results suggest that Mn0.18V2O5@C is a suitable cathode material for AZIBs.

8.
Cell Rep Med ; 4(8): 101130, 2023 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-37490914

RESUMO

Signal regulatory protein (SIRPα) is an immune inhibitory receptor expressed by myeloid cells to inhibit immune cell phagocytosis, migration, and activation. Despite the progress of SIRPα and CD47 antagonist antibodies to promote anti-cancer immunity, it is not yet known whether SIRPα receptor agonism could restrain excessive autoimmune tissue inflammation. Here, we report that neutrophil- and monocyte-associated genes including SIRPA are increased in inflamed tissue biopsies from patients with rheumatoid arthritis and inflammatory bowel diseases, and elevated SIRPA is associated with treatment-refractory ulcerative colitis. We next identify an agonistic anti-SIRPα antibody that exhibits potent anti-inflammatory effects in reducing neutrophil and monocyte chemotaxis and tissue infiltration. In preclinical models of arthritis and colitis, anti-SIRPα agonistic antibody ameliorates autoimmune joint inflammation and inflammatory colitis by reducing neutrophils and monocytes in tissues. Our work provides a proof of concept for SIRPα receptor agonism for suppressing excessive innate immune activation and chronic inflammatory disease treatment.


Assuntos
Colite , Neoplasias , Humanos , Fagocitose , Neoplasias/tratamento farmacológico , Neutrófilos/metabolismo , Inflamação/patologia , Colite/metabolismo
9.
Environ Res ; 226: 115702, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-36931372

RESUMO

The accurate determination of waster sludge water content is crucial to sludge dewatering treatment and its disposal management. Though previous studies highlight the great advantages of low-field nuclear magnetic resonance (LF-NMR) in the determination of sludge water content, its accuracy and applicability are not well studied. Herein, this study investigated the settling of operating parameters and the properties of sludge samples on the accuracy and applicability of LF-NMR method in measuring sludge water content. The results showed that the setting of basic parameters such as standard curve, number of scanning times (NS) and sample weight affected the accuracy of sludge water content by LF-NMR. The standard calibration curve constructed by 3 g/L CuSO4, NS = 8 and the sample weight of about 5 g, were suitable for the accurate determination of sludge water content. Furthermore, the existence of magnetic substances in sludge can affect the distribution gradient of main magnetic field, and thus restricted the applicability of LF-NMR. The saturation magnetization of chemical reagents strongly correlated with the measured relative errors of sludge water content (r = 0.995, p < 0.01), the greater the saturation magnetization of the magnetic material, the greater the error of the test results. On the whole, it is necessary to fully consider the influence of process parameters and sludge properties to evaluate the accuracy and applicability of the LF-NMR method, rather than simply copying the parameters in literatures.


Assuntos
Esgotos , Águas Residuárias , Eliminação de Resíduos Líquidos/métodos , Água/química , Espectroscopia de Ressonância Magnética
10.
Nat Commun ; 13(1): 7280, 2022 11 26.
Artigo em Inglês | MEDLINE | ID: mdl-36435844

RESUMO

Enterovirus A71 (EV-A71)-related hand, foot, and mouth disease (HFMD) imposes a substantial clinical burden in the Asia Pacific region. To inform policy on the introduction of the EV-A71 vaccine into the National Immunization Programme, we investigated the seroepidemiological characteristics of EV-A71 in two prospective cohorts of children in southern China conducted between 2013 and 2018. Our results show that maternal antibody titres declined rapidly in neonates, with over half becoming susceptible to EV-A71 at 1 month of age. Between 6 months and 2 years of age, over 80% of study participants were susceptible, while one third remained susceptible at 5 years old. The highest incidence of EV-A71 infections was observed in children aged 5-6 months. Our findings support EV-A71 vaccination before 6 months for birth cohorts in southern China, potentially with a one-time catch-up vaccination for children 6 months-5 years old. More regionally representative longitudinal seroepidemiological studies are needed to further validate these findings.


Assuntos
Enterovirus Humano A , Infecções por Enterovirus , Enterovirus , Doença de Mão, Pé e Boca , Criança , Recém-Nascido , Humanos , Pré-Escolar , Doença de Mão, Pé e Boca/epidemiologia , Estudos Prospectivos , Estudos Soroepidemiológicos , Infecções por Enterovirus/epidemiologia , China/epidemiologia , Antígenos Virais
11.
BMC Med ; 20(1): 436, 2022 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-36352415

RESUMO

BACKGROUND: A major hand-foot-and-mouth disease (HFMD) pathogen, coxsackievirus A16 (CVA16), has predominated in several of the last 10 years and caused the largest number of HFMD outbreaks between 2011 and 2018 in China. We evaluated the efficacy of maternal anti-CVA16 antibody transfer via the placenta and explored the dynamics of maternal and natural infection-induced neutralizing antibodies in children. METHODS: Two population-based longitudinal cohorts in southern China were studied during 2013-2018. Participants were enrolled in autumn 2013, including 2475 children aged 1-9 years old and 1066 mother-neonate pairs, and followed for 3 years. Blood/cord samples were collected for CVA16-neutralizing antibody detection. The maternal antibody transfer efficacy, age-specific seroprevalence, geometric mean titre (GMT) and immune response kinetics were estimated. RESULTS: The average maternal antibody transfer ratio was 0.88 (95% CI 0.80-0.96). Transferred maternal antibody levels declined rapidly (half-life: 2.0 months, 95% CI 1.9-2.2 months). The GMT decayed below the positive threshold (8) by 1.5 months of age. Due to natural infections, it increased above 8 after 1.4 years and reached 32 by 5 years of age, thereafter dropping slightly. Although the average duration of maternal antibody-mediated protection was < 3 months, the duration extended to 6 months on average for mothers with titres ≥ 64. CONCLUSIONS: Anti-CVA16 maternal antibodies are efficiently transferred to neonates, but their levels decline quickly. Children aged 0-5 years are the main susceptible population and should be protected by CVA16 vaccination, with the optimal vaccination time between 1.5 months and 1 year of age.


Assuntos
Enterovirus Humano A , Enterovirus , Doença de Mão, Pé e Boca , Criança , Recém-Nascido , Animais , Humanos , Lactente , Pré-Escolar , Estudos Soroepidemiológicos , Estudos Longitudinais , Doença de Mão, Pé e Boca/epidemiologia , Doença de Mão, Pé e Boca/prevenção & controle , Anticorpos Neutralizantes , China/epidemiologia , Estudos de Coortes
12.
Cell Rep Med ; 2(8): 100381, 2021 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-34467254

RESUMO

Anti-integrins are therapeutically effective for inflammatory bowel disease, yet the relative contribution of α4ß7 and αEß7 to gut lymphocyte trafficking is not fully elucidated. Here, we evaluate the effect of α4ß7 and αEß7 blockade using a combination of murine models of gut trafficking and longitudinal gene expression analysis in etrolizumab-treated patients with Crohn's disease (CD). Dual blockade of α4ß7 and αEß7 reduces CD8+ T cell accumulation in the gut to a greater extent than blockade of either integrin alone. Anti-αEß7 reduces epithelial:T cell interactions and promotes egress of activated T cells from the mucosa into lymphatics. Inflammatory gene expression is greater in human intestinal αEß7+ T cells. Etrolizumab-treated patients with CD display a treatment-specific reduction in inflammatory and cytotoxic intraepithelial lymphocytes (IEL) genes. Concurrent blockade of α4ß7 and αEß7 promotes reduction of cytotoxic IELs and inflammatory T cells in the gut mucosa through a stepwise inhibition of intestinal tissue entry and retention.


Assuntos
Doenças Inflamatórias Intestinais/imunologia , Integrinas/metabolismo , Linfócitos/imunologia , Animais , Anticorpos Monoclonais Humanizados/farmacologia , Biópsia , Linfócitos T CD8-Positivos , Caderinas/metabolismo , Comunicação Celular , Movimento Celular , Colo/patologia , Epitopos/imunologia , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Inflamação/complicações , Inflamação/patologia , Doenças Inflamatórias Intestinais/complicações , Doenças Inflamatórias Intestinais/patologia , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/imunologia , Mucosa Intestinal/patologia , Linfonodos/patologia , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Linfócitos T Citotóxicos/efeitos dos fármacos
13.
Cell Death Dis ; 12(7): 693, 2021 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-34247201

RESUMO

Nuclear factor erythroid 2-related factor 2 (NRF2) is aberrantly activated in about 93% of pancreatic cancers. Activated NRF2 regulates multiple downstream molecules involved in cancer cell metabolic reprogramming, translational control, and treatment resistance; however, targeting NRF2 for pancreatic cancer therapy remains largely unexplored. In this study, we used the online computational tool CellMinerTM to explore the NCI-60 drug databases for compounds with anticancer activities correlating most closely with the mRNA expression of NQO1, a marker for NRF2 pathway activity. Among the >100,000 compounds analyzed, NSC84167, termed herein as NRF2 synthetic lethality compound-01 (NSLC01), was one of the top hits (r = 0.71, P < 0.001) and selected for functional characterization. NSLC01 selectively inhibited the viabilities of four out of seven conventional pancreatic cancer cell lines and induced dramatic apoptosis in the cells with high NRF2 activation. The selective anticancer activity of NSLC01 was further validated with a panel of nine low-passage pancreatic patient-derived cell lines, and a significant reverse correlation between log(IC50) of NSLC01 and NQO1 expression was confirmed (r = -0.5563, P = 0.024). Notably, screening of a panel of nine patient-derived xenografts (PDXs) revealed six PDXs with high NQO1/NRF2 activation, and NSLC01 dramatically inhibited the viabilities and induced apoptosis in ex vivo cultures of PDX tumors. Consistent with the ex vivo results, NSLC01 inhibited the tumor growth of two NRF2-activated PDX models in vivo (P < 0.01, n = 7-8) but had no effects on the NRF2-low counterpart. To characterize the mechanism of action, we employed a metabolomic isotope tracer assay that demonstrated that NSLC01-mediated inhibition of de novo synthesis of multiple amino acids, including asparagine and methionine. Importantly, we further found that NSLC01 suppresses the eEF2K/eEF2 translation elongation cascade and protein translation of asparagine synthetase. In summary, this study identified a novel compound that selectively targets protein translation and induces synthetic lethal effects in NRF2-activated pancreatic cancers.


Assuntos
Antineoplásicos/farmacologia , Asparagina/biossíntese , Aspartato-Amônia Ligase/metabolismo , NAD(P)H Desidrogenase (Quinona)/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Neoplasias Pancreáticas/tratamento farmacológico , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Quinase do Fator 2 de Elongação/metabolismo , Humanos , Camundongos Endogâmicos NOD , Camundongos SCID , NAD(P)H Desidrogenase (Quinona)/genética , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Carga Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
14.
JCI Insight ; 6(17)2021 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-34237033

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) tumors are characterized by a desmoplastic reaction resulting in dense deposition of collagen that is known to promote cancer progression. A central mediator of protumorigenic collagen signaling is the receptor tyrosine kinase discoid domain receptor 1 (DDR1). DDR1 is a critical driver of a mesenchymal and invasive cancer cell PDAC phenotype. Previous studies have demonstrated that genetic or pharmacologic inhibition of DDR1 reduces PDAC tumorigenesis and metastasis. Here, we investigated whether DDR1 signaling has cancer cell nonautonomous effects that promote PDAC progression and metastasis. We demonstrate that collagen-induced DDR1 activation in cancer cells is a major stimulus for CXCL5 production, resulting in the recruitment of tumor-associated neutrophils (TANs), the formation of neutrophil extracellular traps (NETs), and subsequent cancer cell invasion and metastasis. Moreover, we have identified that collagen-induced CXCL5 production was mediated by a DDR1/PKCθ/SYK/NF-κB signaling cascade. Together, these results highlight the critical contribution of the collagen I-DDR1 interaction in the formation of an immune microenvironment that promotes PDAC metastasis.


Assuntos
Carcinoma Ductal Pancreático/genética , Receptor com Domínio Discoidina 1/genética , Armadilhas Extracelulares/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Experimentais , Neutrófilos/patologia , Neoplasias Pancreáticas/genética , Animais , Carcinogênese , Carcinoma Ductal Pancreático/metabolismo , Carcinoma Ductal Pancreático/secundário , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , DNA de Neoplasias/genética , Receptor com Domínio Discoidina 1/biossíntese , Armadilhas Extracelulares/metabolismo , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Nus , Metástase Neoplásica , Neutrófilos/metabolismo , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Transdução de Sinais , Microambiente Tumoral
15.
Cancer Res ; 81(15): 4054-4065, 2021 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-34117030

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) is almost universally lethal. A critical unmet need exists to explore essential susceptibilities in PDAC and to identify druggable targets to improve PDAC treatment. KRAS mutations dominate the genetic landscape of PDAC and lead to activation of multiple downstream pathways and cellular processes. Here, we investigated the requirement of these pathways for tumor maintenance using an inducible KrasG12D -driven PDAC mouse model (iKras model), identifying that RAF-MEK-MAPK signaling is the major effector for oncogenic KRAS-mediated tumor maintenance. However, consistent with previous studies, MEK inhibition had minimal therapeutic effect as a single agent for PDAC in vitro and in vivo. Although MEK inhibition partially downregulated transcription of glycolysis genes, it failed to suppress glycolytic flux in PDAC cells, which is a major metabolic effector of oncogenic KRAS. Accordingly, an in vivo genetic screen identified multiple glycolysis genes as potential targets that may sensitize tumor cells to MEK inhibition. Inhibition of glucose metabolism with low-dose 2-deoxyglucose in combination with a MEK inhibitor induced apoptosis in KrasG12D -driven PDAC cells in vitro. The combination also inhibited xenograft PDAC tumor growth and prolonged overall survival in a genetically engineered PDAC mouse model. Molecular and metabolic analyses indicated that co-targeting glycolysis and MAPK signaling results in apoptosis via induction of lethal endoplasmic reticulum stress. Together, our work suggests that combined inhibition of glycolysis and the MAPK pathway may serve as an effective approach to target KRAS-driven PDAC. SIGNIFICANCE: This study demonstrates the critical role of glucose metabolism in resistance to MAPK inhibition in KRAS-driven pancreatic cancer, uncovering a potential therapeutic approach for treating this aggressive disease.


Assuntos
Adenocarcinoma/tratamento farmacológico , Carcinoma Ductal Pancreático/tratamento farmacológico , Glucose/metabolismo , Inibidores de Proteínas Quinases/uso terapêutico , Animais , Humanos , Camundongos , Inibidores de Proteínas Quinases/farmacologia
16.
Cancer Discov ; 11(8): 2094-2111, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33839689

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) is almost uniformly fatal and characterized by early metastasis. Oncogenic KRAS mutations prevail in 95% of PDAC tumors and co-occur with genetic alterations in the TP53 tumor suppressor in nearly 70% of patients. Most TP53 alterations are missense mutations that exhibit gain-of-function phenotypes that include increased invasiveness and metastasis, yet the extent of direct cooperation between KRAS effectors and mutant p53 remains largely undefined. We show that oncogenic KRAS effectors activate CREB1 to allow physical interactions with mutant p53 that hyperactivate multiple prometastatic transcriptional networks. Specifically, mutant p53 and CREB1 upregulate the prometastatic, pioneer transcription factor FOXA1, activating its transcriptional network while promoting WNT/ß-catenin signaling, together driving PDAC metastasis. Pharmacologic CREB1 inhibition dramatically reduced FOXA1 and ß-catenin expression and dampened PDAC metastasis, identifying a new therapeutic strategy to disrupt cooperation between oncogenic KRAS and mutant p53 to mitigate metastasis. SIGNIFICANCE: Oncogenic KRAS and mutant p53 are the most commonly mutated oncogene and tumor suppressor gene in human cancers, yet direct interactions between these genetic drivers remain undefined. We identified a cooperative node between oncogenic KRAS effectors and mutant p53 that can be therapeutically targeted to undermine cooperation and mitigate metastasis.This article is highlighted in the In This Issue feature, p. 1861.


Assuntos
Carcinoma Ductal Pancreático/genética , Genes p53/genética , Neoplasias Pancreáticas/genética , Proteínas Proto-Oncogênicas p21(ras)/genética , Animais , Carcinoma Ductal Pancreático/patologia , Feminino , Redes Reguladoras de Genes , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Nus , Metástase Neoplásica , Neoplasias Pancreáticas/patologia
17.
Hum Vaccin Immunother ; 17(2): 592-600, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-32643509

RESUMO

China has achieved high vaccination coverage under the Expanded Program on Immunization (EPI) in children 1-2 years of age. However, a knowledge gap exists regarding vaccination coverage and timeliness for children >2 years of age. As such, this study aimed to estimate coverage and timeliness for all EPI and selected non-EPI vaccines within a rural area of China. Immunization data for 5091 children, born between September 2003 and November 2015, were collected from vaccination cards obtained during sero-surveillance follow-up visits and/or from the Hunan immunization information system. For each dose of both EPI and non-EPI vaccines, vaccination coverage and timeliness were calculated, and temporal variations were examined across birth cohorts. We found coverage for EPI vaccines scheduled for <12 months was 97.1%-99.4%. However, for EPI vaccines scheduled at 6 years coverage was 44.4%-51.7%. The timeliness for EPI vaccines was generally poor, especially for EPI vaccines introduced after 2008 or scheduled for administration at ≥12 months, with a maximum of 35.4% of children vaccinated according to schedule. Despite this, we found increasing trends in vaccination coverage and improvements in timeliness for EPI vaccines. However, for non-EPI vaccines, we found only moderate increases, and in some cases decreases, in vaccination coverage. This study demonstrates the success and improvement of the Chinese immunization program, but also highlights some challenges to be addressed. We recommend that future changes in vaccine practice and policy should primarily focus on improving coverage and timeliness of vaccines introduced after 2008, and/or scheduled for administration ≥12 months.


Assuntos
Cobertura Vacinal , Vacinas , Criança , China , Humanos , Programas de Imunização , Esquemas de Imunização , Lactente , Vacinação
18.
Lancet Infect Dis ; 21(3): 418-426, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33031750

RESUMO

BACKGROUND: Since 1997, epidemics of hand, foot, and mouth disease associated with enterovirus A71 (EV-A71) have affected children younger than 5 years in the Asia-Pacific region, including mainland China. EV-A71 vaccines have been licensed for use in children aged 6-71 months in China, but not for infants younger than 6 months. We aimed to assess the dynamics of maternal EV-A71 antibodies to inform choice of potential vaccination strategies to protect infants younger than 6 months, because they have a substantial burden of disease. METHODS: We did a longitudinal cohort study with mother-neonate pairs in local hospitals in southern China during 2013-18. We collected cord blood from neonates and venous blood from mothers at delivery. We followed up and collected blood samples from the children at ages 2, 4, 6, 12, 24, and 36 months and tested for the presence of neutralising antibodies against EV-A71 with virus neutralisation assays. Seropositivity, or protective titre, was defined as a neutralisation antibody titre of 16 or higher. We estimated the seroprevalence, geometric mean titre (GMT), and transfer ratio of maternal antibodies. We used a binomial distribution to derive the 95% CIs of seroprevalence. Seropositivity between mothers and neonates was compared by use of an agreement (κ), while GMTs were compared by use of paired Student's t tests. FINDINGS: Between Sept 20, 2013, and Oct 14, 2015, 1054 mothers with 1066 neonates were enrolled. The EV-A71 GMT was similar among pairs of neonates (22·7, 95% CI 20·8-24·9) and mothers (22·1, 95% CI 20·2-24·1; p=0·20). The mean transfer ratio of maternal antibodies was 1·03 (95% CI 0·98-1·08). Although 705 (66%) of 1066 neonates acquired protective concentrations of EV-A71 antibodies from mothers, these declined rapidly, with a half-life of 42 days (95% CI 40-44). The time to loss of protective immunity was extended to 5 months in neonates with mothers who had titres of 128 or higher. By age 30 months, 28% of children had become seropositive because of natural infection. INTERPRETATION: EV-A71 maternal antibodies were efficiently transferred to neonates, but declined quickly to below the protective threshold, particularly among those whose mothers had low antibody titres. Our findings suggest that maternal vaccination could be explored to provide neonatal protection against EV-A71 through maternal antibodies. Catch-up vaccination between ages 6 months to 5 years could provide protection to the approximately 30-90% of children that have not had natural EV-A71 infection by that age. FUNDING: National Science Fund for Distinguished Young Scholars, National Natural Science Foundation of China.


Assuntos
Anticorpos Neutralizantes/sangue , Enterovirus Humano A/imunologia , Infecções por Enterovirus/sangue , Infecções por Enterovirus/imunologia , Vacinação/estatística & dados numéricos , Adolescente , Adulto , Pré-Escolar , China , Feminino , Doença de Mão, Pé e Boca/sangue , Doença de Mão, Pé e Boca/prevenção & controle , Humanos , Lactente , Recém-Nascido , Modelos Logísticos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Relações Mãe-Filho , Estudos Soroepidemiológicos , Vacinas Virais/imunologia , Adulto Jovem
19.
Cancer Med ; 8(18): 7705-7719, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31568691

RESUMO

Despite advances in cancer therapeutics, pancreatic cancer remains difficult to treat and often develops resistance to chemotherapies. We have evaluated a bioavailable genistein analogue, AXP107-11 which has completed phase Ib clinical trial, as an approach to sensitize tumor cells to chemotherapy. Using organotypic cultures of 14 patient-derived xenografts (PDX) of pancreatic ductal adenocarcinoma, we found that addition of AXP107-11 indeed sensitized 57% of cases to gemcitabine treatment. Results were validated using PDX models in vivo. Further, RNA-Seq from responsive and unresponsive tumors proposed a 41-gene treatment-predictive signature. Functional and molecular assays were performed in cell lines and demonstrated that the effect was synergistic. Transcriptome analysis indicated activation of G-protein-coupled estrogen receptor (GPER1) as the main underlying mechanism of action, which was corroborated using GPER1-selective agonists and antagonists. GPER1 expression in pancreatic tumors was indicative of survival, and our study proposes that activation of GPER1 may constitute a new avenue for pancreatic cancer therapeutics.


Assuntos
Carcinoma Ductal Pancreático/metabolismo , Genisteína/farmacologia , Neoplasias Pancreáticas/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Receptores de Estrogênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Carcinoma Ductal Pancreático/diagnóstico , Carcinoma Ductal Pancreático/tratamento farmacológico , Linhagem Celular Tumoral , Proliferação de Células , Sobrevivência Celular/efeitos dos fármacos , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacologia , Desoxicitidina/uso terapêutico , Modelos Animais de Doenças , Sinergismo Farmacológico , Feminino , Genisteína/análogos & derivados , Genisteína/uso terapêutico , Humanos , Camundongos , Modelos Biológicos , Mucina-1/genética , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/tratamento farmacológico , Inibidores de Proteínas Quinases/uso terapêutico , Ensaios Antitumorais Modelo de Xenoenxerto , Gencitabina
20.
mSystems ; 4(2)2019.
Artigo em Inglês | MEDLINE | ID: mdl-30944880

RESUMO

Intestinal bacterial dysbiosis has been increasingly linked to ankylosing spondylitis (AS), which is a prototypic and best studied subtype of spondyloarthritis (SpA). Fungi and bacteria coexist in the human gut and interact with each other. Although they have been shown to contribute actively to health or disease, no studies have investigated whether the fungal microbiota in AS patients is perturbed. In this study, fecal samples from 22 AS patients, with clinical and radiographic assessments, and 16 healthy controls (HCs) were collected to systematically characterize the gut microbiota and mycobiota in AS patients by 16S rRNA gene- and ITS2-based DNA sequencing. Our results showed that the microbiota of AS patients was characterized by increased abundance of Proteobacteria and decreased Bacteroidetes, which was contributed by enrichment of Escherichia-Shigella, Veillonella, Lachnospiraceae NK4A136 group, and reduction of Prevotella strain 9, Megamona, and Fusobacterium. The gut mycobiota of AS patients was characterized by higher levels of Ascomycota, especially the class of Dothideomycetes, and decreased abundance of Basidiomycota, which was mainly contributed by the decease of Agaricales. Compared to HCs, decreased ITS2/16S biodiversity ratios and altered bacterial-fungal interkingdom networks were observed in AS patients. Compared with nonsteroidal anti-inflammatory drugs (NSAIDs), treating AS patients with biological agents induced obvious changes in the gut mycobiota, and this result was highly associated with disease activity indexes, including AS disease activity index (ASDAS) C-reactive protein (asCRP), erythrocyte sedimentation rate (ESR), and Bath AS disease activity index (BASDAI). In addition, altered mycobiota in AS patients was also found associated with the degree of radiographic damage. IMPORTANCE The human gut is colonized by diverse fungi (mycobiota), and fungi have long been suspected in the pathogenesis of SpA. Our study unraveled a disease-specific interkingdom network alteration in AS, suggesting that fungi, or the interkingdom interactions between bacteria and fungi, may play an essential role in AS development. However, our study is limited by sample size, and in-depth mechanism studies and additional large-scale investigations characterizing the gut mycobiome in AS patients are needed to form a foundation for research into the relationship between mycobiota dysbiosis and AS development.

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