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1.
J Am Chem Soc ; 145(32): 17689-17699, 2023 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-37550880

RESUMO

Covalent organic frameworks (COFs) have emerged as a promising class of crystalline porous materials for cancer phototherapy, due to their exceptional characteristics, including light absorption, biocompatibility, and photostability. However, the aggregation-caused quenching effect and apoptosis resistance often limit their therapeutic efficacy. Herein, we demonstrated for the first time that linking luminogens with aggregation-induced emission effect (AIEgens) into COF networks via vinyl linkages was an effective strategy to construct nonmetallic pyroptosis inducers for boosting antitumor immunity. Mechanistic investigations revealed that the formation of the vinyl linkage in the AIE COF endowed it with not only high brightness but also strong light absorption ability, long lifetime, and high quantum yield to favor the generation of reactive oxygen species for eliciting pyroptosis. In addition, the synergized system of the AIE COF and αPD-1 not only effectively eradicated primary and distant tumors but also inhibited tumor recurrence and metastasis in a bilateral 4T1 tumor model.


Assuntos
Estruturas Metalorgânicas , Fotoquimioterapia , Piroptose , Apoptose , Carbono , Cloreto de Polivinila
2.
Acta Biomater ; 166: 552-566, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37236575

RESUMO

Immune checkpoint blockade (ICB) therapy has shown great potential in the treatment of malignant tumors, but its therapeutic effect on glioblastoma (GBM) is unsatisfactory because of the low immunogenicity and T cell infiltration, as well as the presence of blood-brain barrier (BBB) that blocks most of ICB agents to the GBM tissues. Herein, we developed a biomimetic nanoplatform of AMNP@CLP@CCM for GBM-targeted photothermal therapy (PTT) and ICB synergistic therapy by loading immune checkpoint inhibitor CLP002 into the allomelanin nanoparticles (AMNPs) and followed by coating cancer cell membranes (CCM). The resulting AMNP@CLP@CCM can successfully cross the BBB and deliver CLP002 to GBM tissues due to the homing effect of CCM. As a natural photothermal conversion agent, AMNPs are used for tumor PTT. The increased local temperature by PTT not only enhances BBB penetration but also upregulates the PD-L1 level on GBM cells. Importantly, PTT can effectively stimulate immunogenic cell death to induce tumor-associated antigen exposure and promote T lymphocyte infiltration, which can further amplify the antitumor immune responses of GBM cells to CLP002-mediated ICB therapy, resulting in significant growth inhibition of the orthotopic GBM. Therefore, AMNP@CLP@CCM has great potential for the treatment of orthotopic GBM by PTT and ICB synergistic therapy. STATEMENT OF SIGNIFICANCE: The effect of ICB therapy on GBM is limited by the low immunogenicity and insufficient T-cell infiltration. Here we developed a biomimetic nanoplatform of AMNP@CLP@CCM for GBM-targeted PTT and ICB synergistic therapy. In this nanoplatform, AMNPs are used as both photothermal conversion agents for PTT and nanocarriers for CLP002 delivery. PTT not only enhances BBB penetration but also upregulates the PD-L1 level on GBM cells by increasing local temperature. Additionally, PTT also induces tumor-associated antigen exposure and promotes T lymphocyte infiltration to amplify the antitumor immune responses of GBM cells to CLP002-mediated ICB therapy, resulting in significant growth inhibition of the orthotopic GBM. Thus, this nanoplatform holds great potential for orthotopic GBM treatment.


Assuntos
Glioblastoma , Nanopartículas , Humanos , Fototerapia/métodos , Antígeno B7-H1 , Melaninas , Glioblastoma/terapia , Glioblastoma/patologia , Biomimética , Imunoterapia , Nanopartículas/uso terapêutico , Linhagem Celular Tumoral
3.
Adv Mater ; 35(19): e2205409, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36121368

RESUMO

As an essential micronutrient, manganese (Mn) participates in various physiological processes and plays important roles in host immune system, hematopoiesis, endocrine function, and oxidative stress regulation. Mn-based nanoparticles are considered to be biocompatible and show versatile applications in nanomedicine, in particular utilized in tumor immunotherapy in the following ways: 1) acting as a biocompatible nanocarrier to deliver immunotherapeutic agents for tumor immunotherapy; 2) serving as an adjuvant to regulate tumor immune microenvironment and enhance immunotherapy; 3) activating host's immune system through the cGAS-STING pathway to trigger tumor immunotherapy; 4) real-time monitoring tumor immunotherapy effect by magnetic resonance imaging (MRI) since Mn2+ ions are ideal MRI contrast agent which can significantly enhance the T1 -weighted MRI signal after binding to proteins. This comprehensive review focuses on the most recent progress of Mn-based nanoplatforms in tumor immunotherapy. The characteristics of Mn are first discussed to guide the design of Mn-based multifunctional nanoplatforms. Then the biomedical applications of Mn-based nanoplatforms, including immunotherapy alone, immunotherapy-involved multimodal synergistic therapy, and imaging-guided immunotherapy are discussed in detail. Finally, the challenges and future developments of Mn-based tumor immunotherapy are highlighted.


Assuntos
Nanopartículas , Neoplasias , Humanos , Manganês/uso terapêutico , Nanopartículas/uso terapêutico , Imageamento por Ressonância Magnética/métodos , Neoplasias/terapia , Neoplasias/tratamento farmacológico , Imunoterapia , Microambiente Tumoral
4.
Front Vet Sci ; 9: 954675, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35990281

RESUMO

Guanidine acetic acid (GAA) is increasingly considered as a nutritional growth promoter in monogastric animals. Whether or not such response would exist in rapid-growing lambs is unclear yet. The objective of this study was to investigate whether dietary supplementation with uncoated GAA (UGAA) and coated GAA (CGAA) could alter growth performance, nutrient digestion, serum metabolites, and antioxidant capacity in lambs. Seventy-two small-tailed Han lambs initially weighed 12 ± 1.6 kg were randomly allocated into six groups in a 2 × 3 factorial experimental design including two forage-type rations [Oaten hay (OH) vs. its combination with wheat silage (OHWS)] and three GAA treatment per ration: no GAA, 1 g UGAA, and 1 g CGAA per kg dry matter. The whole experiment was completed in two consecutive growing stages (stage 1, 13-30 kg; stage 2, 30-50 kg). Under high-concentrate feeding pattern (Stage 1, 25: 75; Stage 2, 20: 80), UGAA or CGAA supplementation in young lambs presented greater dry matter intake (DMI) in stage 1 and average daily gain (ADG) in the whole experimental period; lambs in OH group had higher ADG and DMI than that in OHWS group in stage 1 and whole experimental period, but this phenomenon was not observed in stage 2. Both UCGA and CGAA addition increased dietary DM, organic matter (OM), neutral detergent fiber (NDF), and acid detergent fiber (ADF) digestion in both stages. In blood metabolism, UCGA and CGAA addition resulted in a greater total protein (TP) and insulin-like growth factor 1(IGF-1) levels, as well as antioxidant capacity; at the same time, UCGA and CGAA addition increased GAA metabolism-creatine kinase and decreased guanidinoacetate N-methyltransferase (GAMT) and L-Arginine glycine amidine transferase catalyzes (AGAT) activity. In a brief, the results obtained in the present study suggested that GAA (UGAA and CGAA; 1 g/kg DM) could be applied to improve growth performance in younger (13-30 kg) instead of older (30-50 kg) lambs in high-concentrate feedlotting practice.

5.
Pharm Biol ; 60(1): 909-914, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35575436

RESUMO

CONTEXT: Red ginseng polysaccharide (RGP) is an active component of the widely used medicinal plant Panax ginseng C. A. Meyer (Araliaceae), which has displayed promising activities against cancer cells. However, the detailed molecular mechanism of RGP in ferroptosis is still unknown. OBJECTIVE: This study evaluates the effects of RGP in cancer cells. MATERIALS AND METHODS: A549 and MDA-MB-231 cells were used. Cell proliferation was measured by CCK-8 assay after being treated with RGP at concentrations of 0, 50, 100, 200, 400, 800 and 1600 µg/mL at 0, 12, 24 and 48 h. Lipid reactive oxygen species (ROS) levels were assessed by C11-BODIPY assay. The control group was treated with PBS. RESULTS: RGP inhibited human A549 (IC50: 376.2 µg/mL) or MDA-MB-231(IC50: 311.3 µg/mL) proliferation and induced lactate dehydrogenase (LDH) release, promoted ferroptosis and suppressed the expression of GPX4. Moreover, the effects of RGP were enhanced by the ferroptosis inducer erastin, while abolished by ferroptosis inhibitor ferrostatin-1. DISCUSSION AND CONCLUSIONS: Our study is the first to demonstrate (1) the anticancer activity of RGP in human lung cancer and breast cancer. (2) RGP presented the anti-ferroptosis effects in lung and breast cancer cells via targeting GPX4.


Assuntos
Neoplasias da Mama , Ferroptose , Panax , Neoplasias da Mama/tratamento farmacológico , Regulação para Baixo , Feminino , Humanos , Polissacarídeos/farmacologia
6.
Artigo em Chinês | WPRIM | ID: wpr-905245

RESUMO

Objective:To evaluate the efficacy of exercise on preventing falls in the elderly. Methods:Literatures of randomized controlled trials about exercises for prevention of falls in the elderly were retrieved from Web of Science, PubMed, Cochrane Library and CNKI from 1980 to July, 2020. The qualities were evaluated with Review Manager 5.3, and the data were analyzed with R-Studio and Addis 1.16.6. Results:A total of 172 randomized controlled trials were finally included, with nine kinds of exercise intervention. The cognition and movement multitask training was the most effective to decrease fall rate (OR = 0.26, 95%CI 0.14 to 0.49, P < 0.05). The combined physical and whole body vibration training was the most effective to improve the score of Berg Balance Scale (d = 6.3, 95%CI 3.5 to 9.2, P < 0.05) and the time of Timed 'Up & Go' Test (d = -4.5, 95%CI -6.8 to -2.1, P < 0.05). The blood flow restriction training was the most effective to increase the lower limb muscle strength (d = 12, 95%CI 7.4 to 16, P < 0.05). Conclusion:The cognition and movement multitask training is the first recommended exercise to prevent falls in the elderly, followed by Taiji Quan and multimodal training. Gait practice or resistance training are the least effective. A variety of new intervention methods (blood flow restriction training, combined physical and whole body vibration training, Wit Fit training, etc.) may improve the physical function of the elderly, and need further researches.

7.
Zhongguo Zhong Yao Za Zhi ; 45(22): 5465-5471, 2020 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-33350207

RESUMO

In this study, Andrographis paniculata seedlings were used as experimental materials to study the effects of salicylic acid(SA) on the growth and effective component accumulation of A. paniculata under NaCl stress. The results showed that with the increase of NaCl concentration, the growth of A. paniculata seedlings was significantly inhibited, and the content of carotene and carotenoid decreased. The activity of antioxidant enzyme was enhanced. At the same time, the contents of proline, proline and soluble protein were on the rise. The contents of andrographolide, new andrographolide and deoxyandrographolide showed an upward trend, while deoxyandrographolide showed a downward trend. Treatment with 100 mmol·L~(-1) NaCl+5 mg·L~(-1) SA showed a significant increase in antioxidant enzyme activity in A. paniculata leaves. Treatment with 100 mmol·L~(-1) NaCl+10 mg·L~(-1) SA showed significant changes in soluble protein and proline content in A. paniculata leaves, while MDA content in A. paniculata leaves significantly decreased. 10 mg·L~(-1) SA had the best effect on the growth of A. paniculata seedlings under salt stress. Under the treatment of 50 mmol·L~(-1) NaCl+10 mg·L~(-1) SA, fresh weight, dry weight and leaf dry weight of A. paniculata seedlings reached the highest level, which were 1.02, 1.09 and 1.11 times of those in the control group, respectively. The concentrations of NaCl and 10 mg·L~(-1) SA were significantly higher than those of the control group. Four key enzyme genes of A. paniculata diterpene lactone synthesis pathway were selected to explore the molecular mechanism of salicylic acid to alleviate salt stress. With the increase of salt stress, the relative expressions of HMGR, GGPS and ApCPS were up-regulated, indicating that salt stress may enhance the synthesis of A. paniculata diterpene lactone through MVA pathway. SA can effectively promote the growth and development of A. paniculata under salt stress, improve its osmotic regulation and antioxidant capacity, improve its salt tolerance, and alleviate the effects of salt stress on A. paniculata.


Assuntos
Andrographis , Folhas de Planta , Ácido Salicílico , Tolerância ao Sal , Plântula/genética
8.
EBioMedicine ; 62: 103112, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33186810

RESUMO

BACKGROUND: The rapid spread of SARS-CoV-2, the causative agent of Coronavirus disease 2019 (COVID-19), has been accompanied by the emergence of distinct viral clades, though their clinical significance remains unclear. Here, we aimed to investigate the phylogenetic characteristics of SARS-CoV-2 infections in Chicago, Illinois, and assess their relationship to clinical parameters. METHODS: We performed whole-genome sequencing of SARS-CoV-2 isolates collected from COVID-19 patients in Chicago in mid-March, 2020. Using these and other publicly available sequences, we performed phylogenetic, phylogeographic, and phylodynamic analyses. Patient data was assessed for correlations between demographic or clinical characteristics and virologic features. FINDINGS: The 88 SARS-CoV-2 genome sequences in our study separated into three distinct phylogenetic clades. Clades 1 and 3 were most closely related to viral sequences from New York and Washington state, respectively, with relatively broad distributions across the US. Clade 2 was primarily found in the Chicago area with limited distribution elsewhere. At the time of diagnosis, patients infected with Clade 1 viruses had significantly higher average viral loads in their upper airways relative to patients infected with Clade 2 viruses, independent of disease severity. INTERPRETATION: These results show that multiple variants of SARS-CoV-2 were circulating in the Chicago area in mid-March 2020 that differed in their relative viral loads in patient upper airways. These data suggest that differences in virus genotype can impact viral load and may influence viral spread. FUNDING: Dixon Family Translational Research Award, Northwestern University Clinical and Translational Sciences Institute (NUCATS), National Institute of Allergy and Infectious Diseases (NIAID), Lurie Comprehensive Cancer Center, Northwestern University Emerging and Re-emerging Pathogens Program.


Assuntos
COVID-19/genética , Genoma Viral , Genótipo , Filogenia , SARS-CoV-2/genética , Carga Viral , Feminino , Humanos , Masculino , Sequenciamento Completo do Genoma
9.
Carbohydr Polym ; 226: 115304, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31582069

RESUMO

Medicinal herb Bletilla striata as a traditional Chinese herb has been used to treat alimentary canal mucosal damage, ulcers, bruises, and burns for thousands of years. Despite numerous efforts directed at the development of Bletilla striata products, the challenge of preparing Bletilla striata hemostasis dressings while simultaneously maintaining portability and high hemostasis performance has not yet been addressed. Herein, we describe a Bletilla striata polysaccharide (BSP) sponge with hierarchical aligned porous channels formed via directional freeze technology. The microstructure and mechanical property of the BSP sponges could be controlled by modifying the BSP concentration. Notably, in vivo animal studies indicated that BSP sponges show high biocompatibility and degradation and possess excellent hemostasis capability. In addition, BSP sponges showed accelerated wound healing in comparison to commercial dressings. Thus, our study indicates that the constructed BSP sponges could find potential application in dressings for efficient wound healing.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Orchidaceae/metabolismo , Plantas Medicinais/metabolismo , Polissacarídeos/farmacologia , Animais , Bandagens , Materiais Biocompatíveis/farmacologia , Feminino , Hemostasia/efeitos dos fármacos , Masculino , Camundongos Endogâmicos C57BL , Coelhos , Cicatrização
10.
Adv Mater ; 31(21): e1808325, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30907460

RESUMO

Over the past 3 years, glucose oxidase (GOx) has aroused great research interest in the context of cancer treatment due to its inherent biocompatibility and biodegradability, and its unique catalytic properties against ß-d-glucose. GOx can effectively catalyze the oxidation of glucose into gluconic acid and hydrogen peroxide. This process depletes oxygen levels, resulting in elevated acidity, hypoxia, and oxidative stress in the tumor microenvironment. All of these changes can be readily harnessed to develop a multimodal synergistic cancer therapy by combining GOx with other therapeutic approaches. Herein, the representative studies of GOx-instructed multimodal synergistic cancer therapy are introduced, and their synergistic mechanisms are discussed systematically. The current challenges and future prospects to advance the development of GOx-based nanomedicines in this cutting-edge research area are highlighted.


Assuntos
Glucose Oxidase/metabolismo , Neoplasias/terapia , Animais , Biocatálise , Hipóxia Celular , Terapia Combinada , Glucose/metabolismo , Humanos , Nanomedicina , Nanopartículas/química , Neoplasias/tratamento farmacológico , Oxirredução , Estresse Oxidativo/efeitos dos fármacos , Fototerapia/métodos , Microambiente Tumoral
11.
ACS Appl Mater Interfaces ; 9(4): 3306-3317, 2017 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-28068758

RESUMO

Nanostructured calcium phosphate porous microspheres are of great potential in drug delivery and bone regeneration due to their large specific surface area, biocompatibility, and similarity to inorganic component of osseous tissue. In this work, strontium (Sr)-doped amorphous calcium phosphate porous microspheres (SrAPMs) were synthesized through a microwave-hydrothermal method using fructose 1,6-bisphosphate trisodium salt as the source of phosphate ions. The SrAPMs showed a mesoporous structure and a relatively high specific area. Compared with the hydroxyapatite nanorods prepared by using Na2HPO4·12H2O as the phosphorus source, the SrAPMs with a higher specific surface area were more effective in drug loading using vancomycin as the antiobiotics of choice and consequently having a higher antibacterial efficiency both on agar plates and in broths. Furthermore, to assess the potential application of SrAPMs in bone defect repair, a novel biomimetic bone tissue-engineering scaffold consisting of collagen (Coll) and SrAPMs was constructed using a freeze-drying fabrication process. Incorporation of the SrAPMs not only improved the mechanical properties, but also enhanced the osteogenesis of rat bone marrow mesenchymal stem cells. The in vivo experiments demonstrated that the SrAPMs/Coll scaffolds remarkably enhanced new bone formation compared with the Coll and APMs/Coll scaffolds in a rat critical-sized calvarial defect model at 8 weeks postimplantation. In summary, SrAPMs developed in this work are promising as antibiotic carriers and may encourage bone formation when combined with collagen.


Assuntos
Micro-Ondas , Animais , Regeneração Óssea , Fosfatos de Cálcio , Frutose , Frutosedifosfatos , Microesferas , Fósforo , Ratos , Estrôncio , Alicerces Teciduais
12.
Ann Am Thorac Soc ; 13(11): 1956-1961, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27599038

RESUMO

RATIONALE: Clinical recurrence of Mycobacterium avium complex (MAC) pulmonary disease occurs in 10 to 40% of patients treated for this disease process. Episodes of clinical recurrence may represent true relapse from the same MAC strain or reinfection with a new strain. OBJECTIVES: The purpose of this study was to investigate the clinical implications of separating patients into these two groups. METHODS: This retrospective study evaluated patients with a clinical recurrence of MAC pulmonary disease at our institution from 2000 to 2012. Isolates were genotyped using pulsed-field gel electrophoresis to differentiate relapse versus reinfection. Change in macrolide susceptibility was also analyzed. MEASUREMENTS AND MAIN RESULTS: In our cohort, 25% of patients suffered a clinical recurrence. Of the 46 included patients, 25 (54%) suffered a true relapse and 21 (46%) had a reinfection. Median time between completion of therapy and clinical recurrence was significantly lower in the relapse group compared with the reinfection group (210 d vs. 671 d; P = 0.004). The measured convalescent macrolide minimum inhibitory concentrations were significantly more likely to increase in the relapse group compared with the reinfection group (80 vs. 33%; P = 0.002). No differences in clinical outcomes were observed between the two groups at conclusion of the study. CONCLUSIONS: Our findings suggest that patients with true relapse of MAC pulmonary disease present earlier than those with reinfection. Routine use of pulsed-field gel electrophoresis in the management of clinical recurrences may be beneficial, as those suffering a relapse are more likely to have increasing macrolide minimum inhibitory concentrations than those with reinfection.


Assuntos
Antibacterianos/uso terapêutico , Macrolídeos/uso terapêutico , Complexo Mycobacterium avium/isolamento & purificação , Infecção por Mycobacterium avium-intracellulare/diagnóstico , Infecção por Mycobacterium avium-intracellulare/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Farmacorresistência Bacteriana , Feminino , Humanos , Modelos Logísticos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Recidiva , Estudos Retrospectivos , Prevenção Secundária/métodos , Estados Unidos
13.
Artigo em Inglês | MEDLINE | ID: mdl-26562802

RESUMO

In the present work, a simple and efficient chromatographic separation method was developed for preparative separation and enrichment of total flavonoids (TFs) from Cortex Juglandis Mandshuricae (CJM) extracts and then the protective effect of TFs against CCl4-induced acute liver injury in mice was investigated. Enrichment and purification of TFs from CJM extracts were studied using six macroporous resins and HPD-750 resin was selected as the best resin according to its adsorption and desorption properties. The operating parameters of resin column chromatography were optimized. Under the optimal conditions, TFs from CJM with purity larger than 50% were produced and their antioxidant activity was further evaluated in vitro. The mice were orally administrated with the purified TFs for seven days and then given CCl4 (0.3%, 10mL/kg i.p.). The results showed that TFs of CJM significantly attenuated the activities of serum aspartate transaminase (AST) and alanine transaminase (ALT) compared with model group, as well as the relative liver weight. Histopathological observation also revealed that TFs reduced the incidence of liver lesions and improved hepatocyte abnormality. Moreover, oral administration of TFs significantly enhanced antioxidant enzyme activities (superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px)) and decreased the content of malondialdehyde (MDA). Histopathological and biochemical results elicited that TFs of CJM had significant hepatoprotective activity comparable to the standard silymarin. This is the first time to reveal the protective actions of the TFs from CJM against CCl4-induced liver damage in mice and this natural product should be developed as a new drug for treatment of live injury in future.


Assuntos
Intoxicação por Tetracloreto de Carbono/prevenção & controle , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Flavonoides/isolamento & purificação , Juglans/química , Extratos Vegetais/farmacologia , Alanina Transaminase/sangue , Animais , Aspartato Aminotransferases/sangue , Intoxicação por Tetracloreto de Carbono/metabolismo , Intoxicação por Tetracloreto de Carbono/fisiopatologia , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/fisiopatologia , Flavonoides/farmacologia , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Masculino , Camundongos , Tamanho do Órgão/efeitos dos fármacos
14.
J Med Chem ; 58(14): 5419-36, 2015 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-26111355

RESUMO

Induction of phase II antioxidant enzymes by activation of Nrf2/ARE pathway has been recognized as a promising strategy for the regulation of oxidative stress-related diseases. Herein we report our effort on the discovery and optimization of Nrf2 activators with 1,2,4-oxadiazole core. Screening of an in-house collection containing 7500 compounds by ARE-luciferase reporter assay revealed a moderate Nrf2 activator, 1. Aimed at obtaining more derivatives efficiently, molecular similarity search by the combination of 2D fingerprint-based and 3D shape-based search was applied to virtually screening the Chemdiv collection. Three derivatives with the same core were identified to have better inductivity of Nrf2 than 1. The best hit 4 was selected as starting point for structurally optimization, leading to a much more potent derivative 32. It in vitro upregulated gene and protein level of Nrf2 as well as its downstream markers such as NQO1, GCLM, and HO-1. It remarkably suppressed inflammation in the in vivo LPS-challenged mouse model. Our results provide a new chemotype as Nrf2-ARE activators which deserve further optimization with the aim to obtain active anti-inflammatory agents through Nrf2-ARE pathway.


Assuntos
Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Desenho de Fármacos , Fator 2 Relacionado a NF-E2/metabolismo , Oxidiazóis/química , Oxidiazóis/farmacologia , Animais , Elementos de Resposta Antioxidante/efeitos dos fármacos , Avaliação Pré-Clínica de Medicamentos , Feminino , Células HCT116 , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Fator 2 Relacionado a NF-E2/genética , Relação Estrutura-Atividade , Regulação para Cima/efeitos dos fármacos
15.
Diagn Microbiol Infect Dis ; 82(2): 165-71, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25801780

RESUMO

Predicted and observed failures at higher cefepime MICs have prompted the Clinical and Laboratories Standards Institute (CLSI) to lower the susceptible breakpoint for Enterobacteriaceae to ≤2mg/L, with dose-dependent susceptibility at 4-8mg/L, while the susceptibility breakpoint for nonfermentative organisms remain unchanged at ≥8mg/L. The contribution of increasing cefepime MIC to mortality risk in the setting of aggressive cefepime dosing is not well defined. Patients who were treated with cefepime for Gram-negative blood stream infections (GNBSIs), including both Enterobacteriaceae and nonfermentative organisms, were screened for inclusion in this retrospective cohort study. Demographic and microbiologic variables were collected, including pathogen, cefepime MIC, dosage, and interval. The objective was to define a risk-adjusted mortality breakpoint for cefepime MICs. Secondarily, we looked at time to death and length of stay (LOS) postculture. Ninety-one patients were included in the analysis. Overall, 19 patients died and 72 survived. Classification and Regression Tree analysis identified an inhospital mortality breakpoint at a cefepime MIC between 2 and 4mg/L for patients with a modified Acute Physiology and Chronic Health Evaluation II score ≤16.5 (4.2% versus 25%, respectively). Multivariate logistic regression revealed increased odds of mortality at a cefepime MIC of 4mg/L (adjusted odds ratio [aOR] 6.47; 95% confidence interval [CI] 1.25-33.4) and 64mg/L (aOR 6.54, 95% CI 1.03-41.4). Those with cefepime MICs ≥4mg/L experienced a greater median intensive care unit LOS for survivors (16 versus 2days; P=0.026). Increasing cefepime MIC appears to predict inhospital mortality among patients who received aggressive doses of cefepime for GNBSIs, supporting a clinical breakpoint MIC of 2mg/L.


Assuntos
Bacteriemia/tratamento farmacológico , Bacteriemia/microbiologia , Cefalosporinas/farmacologia , Cefalosporinas/uso terapêutico , Bactérias Gram-Negativas/efeitos dos fármacos , Infecções por Bactérias Gram-Negativas/tratamento farmacológico , Infecções por Bactérias Gram-Negativas/microbiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Bacteriemia/mortalidade , Cefepima , Estudos de Coortes , Feminino , Bactérias Gram-Negativas/isolamento & purificação , Infecções por Bactérias Gram-Negativas/mortalidade , Humanos , Tempo de Internação , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Estudos Retrospectivos , Análise de Sobrevida , Resultado do Tratamento
16.
BMC Complement Altern Med ; 14: 377, 2014 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-25283233

RESUMO

BACKGROUND: Lung cancers are leading causes of cancer death, and Rumex japonicus has been traditionally used in folk medicine as anti-microorganic, anti-inflammatory and anti-tumor agents. This study was designed to investigate the anti-proliferative activity of physcion 8-O-ß-glucopyranoside (PG) isolated from Rumex japonicus Houtt. on A549 cell lines. METHODS: In our present study, PG was isolated and identified from the ethanol extracts of R. japonicus. MTT method was used to evaluate the anti-proliferative activity of PG on A549 cell lines, and cell cycle distribution assay, apoptosis assay, and western blot analysis in vitro were used to explore the possible mechanisms. RESULTS: From the results of our present study, cell viability was obviously inhibited by PG, in a dose- and time-dependent manner. Our results also suggested that the anti-proliferative effect of PG was related to cell cycle arrest at the G2/M phase through repression of cdc2 and Cyclin B1 protein expression. In addition, the results of apoptosis assay and western blot analysis indicated that the anti-proliferative activity could be related to apoptosis via up-regulating the expressions of Bax, caspase-3 and caspase-7, and down-regulating the expressions of Bcl-2. CONCLUSIONS: In conclusion, the PG has significant anti-proliferative activity on A549 cell lines, and the possible mechanism was related to cell cycle arrest at the G2/M phase, and apoptosis via the regulations of Bax, Bcl-2, and caspase-3 and caspase-7.


Assuntos
Antineoplásicos/farmacologia , Emodina/análogos & derivados , Glicosídeos/farmacologia , Extratos Vegetais/farmacologia , Rumex/química , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Emodina/química , Emodina/farmacologia , Glicosídeos/química , Humanos , Extratos Vegetais/química
17.
Artigo em Inglês | MEDLINE | ID: mdl-24704688

RESUMO

Cortex Juglandis Mandshuricae is used as a folk remedy for treating cancer, diarrhea and dysentery in traditional Chinese medicine for many years. Six flavonoids (myricitrin, quercitrin, taxifolin, myricetin, quercetin and naringenin), gallic acid and 5,8-dihydroxy-1,4-naphthoquinone are major bioactive components in Cortex Juglandis Mandshuricae extract. In this study, an ultrahigh performance liquid chromatography and tandem mass spectrometry method was developed for simultaneous determination of eight ingredients in rat plasma using chloromycetin as an internal standard. Plasma samples added vitamin C (antioxygen) were acidified with hydrochloric acid and extracted by liquid-liquid extraction with ethyl acetate. Eight ingredients were separated on a Venusil ASB C18 column and detected by multiple reaction monitoring mode using electrospray ionization in the negative ion mode. The method was linear for all analytes over investigated range with all correlation coefficients greater than 0.9900. The validated lower limit of quantification was 20ng/mL for gallic acid, 5ng/mL for myricitrin, 3ng/mL for quercitrin, 10ng/mL for taxifolin, 6ng/mL for myricetin, 3ng/mL for quercetin, 2ng/mL for naringenin and 1µg/mL for 5,8-dihydroxy-1,4-naphthoquinone, respectively. Intra- and inter-day precisions (RSD%) were less than 15% and accuracy (RE%) ranged from -6.9% to 6.9%. The validated method was successfully applied to investigate the pharmacokinetics of the eight analytes after oral administration of Cortex Juglandis Mandshuricae extract to rats.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/farmacocinética , Flavonoides/sangue , Ácido Gálico/sangue , Naftoquinonas/sangue , Espectrometria de Massas em Tandem/métodos , Animais , Medicamentos de Ervas Chinesas/administração & dosagem , Limite de Detecção , Masculino , Ratos , Ratos Wistar
18.
Asian Pac J Cancer Prev ; 15(24): 10847-53, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25605188

RESUMO

BACKGROUND: Lapatinib, a dual tyrosine kinase inhibitor that interrupts the epidermal growth factor receptor (EGFR) and HER2/neu pathways, has been indicated to have significant efficacy in treating HER2-positive breast cancer. However, acquired drug resistance has become a very serious clinical problem that hampers the use of this agent. In this study, we aimed to screen small molecule drugs that might reverse lapatinib-resistance of breast cancer by exploring differentially expressed genes (DEGs) via a bioinformatics method. MATERIALS AND METHODS: We downloaded the gene expression profile of BT474-J4 (acquired lapatinib-resistant) and BT474 (lapatinib-sensitive) cell lines from the Gene Expression Omnibus (GEO) database and selected differentially expressed genes (DEGs) using dChip software. Then, gene ontology and pathway enrichment analyses were performed with the DAVID database. Finally, a connectivity map was utilized for predicting potential chemicals that reverse lapatinib-resistance. RESULTS: A total of 1, 657 DEGs were obtained. These DEGs were enriched in 10 pathways, including cell cycling, regulation of actin cytoskeleton and focal adhesion associate examples. In addition, several small molecules were screened as the potential therapeutic agents capable of overcoming lapatinib-resistance. CONCLUSIONS: The results of our analysis provided a novel strategy for investigating the mechanism of lapatinib-resistance and identifying potential small molecule drugs for breast cancer treatment.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Biologia Computacional/métodos , Resistencia a Medicamentos Antineoplásicos/genética , Perfilação da Expressão Gênica , Quinazolinas/farmacologia , Bibliotecas de Moléculas Pequenas/farmacologia , Antineoplásicos/farmacologia , Bases de Dados Genéticas , Descoberta de Drogas , Avaliação Pré-Clínica de Medicamentos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Lapatinib , Receptor ErbB-2/metabolismo
19.
Chemistry ; 19(17): 5332-41, 2013 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-23460360

RESUMO

Hierarchically nanostructured porous hollow microspheres of hydroxyapatite (HAP) are a promising biomaterial, owing to their excellent biocompatibility and porous hollow structure. Traditionally, synthetic hydroxyapatite is prepared by using an inorganic phosphorus source. Herein, we report a new strategy for the rapid, sustainable synthesis of HAP hierarchically nanostructured porous hollow microspheres by using creatine phosphate disodium salt as an organic phosphorus source in aqueous solution through a microwave-assisted hydrothermal method. The as-obtained products are characterized by powder X-ray diffraction (XRD), Fourier-transform IR (FTIR) spectroscopy, SEM, TEM, Brunauer-Emmett-Teller (BET) nitrogen sorptometry, dynamic light scattering (DLS), and thermogravimetric analysis (TGA). SEM and TEM micrographs show that HAP hierarchically nanostructured porous hollow microspheres consist of HAP nanosheets or nanorods as the building blocks and DLS measurements show that the diameters of HAP hollow microspheres are within the range 0.8-1.5 µm. The specific surface area and average pore size of the HAP porous hollow microspheres are 87.3 m(2) g(-1) and 20.6 nm, respectively. The important role of creatine phosphate disodium salt and the influence of the experimental conditions on the products were systematically investigated. This method is facile, rapid, surfactant-free and environmentally friendly. The as-prepared HAP porous hollow microspheres show a relatively high drug-loading capacity and protein-adsorption ability, as well as sustained drug and protein release, by using ibuprofen as a model drug and hemoglobin (Hb) as a model protein, respectively. These experiments indicate that the as-prepared HAP porous hollow microspheres are promising for applications in biomedical fields, such as drug delivery and protein adsorption.


Assuntos
Materiais Biocompatíveis/síntese química , Durapatita/química , Nanoestruturas , Fosfocreatina/química , Adsorção , Materiais Biocompatíveis/química , Sistemas de Liberação de Medicamentos/métodos , Hemoglobinas/análise , Ibuprofeno/análise , Microesferas , Micro-Ondas , Nanotubos , Nitrogênio , Fósforo/química , Porosidade , Difração de Raios X
20.
Chem Asian J ; 8(1): 88-94, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23192854

RESUMO

Calcium phosphates (CPs), as the major inorganic component of biological hard tissues, have been investigated for applications as biomaterials owing to their excellent biocompatibility. However, the traditional synthetic CPs are usually prepared from inorganic phosphorus and calcium sources. Herein, we report a new strategy for the synthesis of a variety of calcium-phosphate nanostructures, including porous amorphous calcium phosphate (ACP) microspheres, hydroxyapatite (HAP) nanorods, and ACP/HAP composite microspheres, by using fructose 1,6-bisphosphate trisodium salt (FBP) as an organic phosphorus source in aqueous solution in a rapid microwave-assisted hydrothermal reaction. The important role of FBP and the effect of the experimental conditions on the formation and evolution of the CPs nanostructures were investigated. The crystal phase and composition of the as-prepared products were characterized by powder X-ray diffraction (XRD), FTIR spectroscopy, and thermogravimetric (TGA) analysis and the morphologies of the products were characterized by SEM and TEM. This method is facile, rapid, surfactant-free, and environmentally friendly. The as-prepared porous ACP microspheres have a relatively high drug-loading capacity and good sustained drug-release behavior; thus, they are promising for applications in drug delivery.


Assuntos
Fosfatos de Cálcio/química , Portadores de Fármacos , Frutosedifosfatos/química , Microesferas , Micro-Ondas , Fósforo/química , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Sais , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
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