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1.
Chin Med ; 19(1): 24, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38355571

RESUMO

BACKGROUND: Encephalitis caused by dengue virus (DENV) is considered a manifestation of severe dengue. Tanreqing injection (TRQ) is a well-known Chinese patented medicine, which has been used to treat brain-related disorders by inhibiting inflammation. Nevertheless, the effects of TRQ on DENV encephalitis have not been studied. The aim of this study was to evaluate the effects of TRQ on DENV encephalitis and to explore its potential mechanisms. METHODS: The cytotoxicity of TRQ was examined by MTT assay, and the anti-DENV activities of TRQ in BHK-21 baby hamster kidney fibroblast were evaluated through CCK-8 and plaque assays. The expression levels of NO, IL1B/IL-1ß, TNFα and IL6 were measured by qRT‒PCR and ELISA in the BV2 murine microglial cell line. The inhibitory effects of TRQ on NLRP3 inflammasome activation in BV2 cells were examined by Western blotting, qRT‒PCR and ELISA. The effects of TRQ on HT22 mouse hippocampal neuronal cells were examined by CCK-8 assay, morphology observation and flow cytometry. Moreover, a DENV-infected ICR suckling mouse model was developed to investigate the protective role of TRQ in vivo. RESULTS: TRQ decreased the release of NO, IL6, TNFα and IL1B from BV2 cells and inhibited the activation of NLRP3. The presence of the NLRP3 agonist nigericin reversed the anti-inflammatory activities of TRQ. Furthermore, TRQ inhibited the death of HT22 cells by decreasing IL1B in DENV-infected BV2 cells. In addition, TRQ significantly attenuated weight loss, reduced clinical scores and extended the survival in DENV-infected ICR suckling mice. Critically, TRQ ameliorated pathological changes in ICR suckling mice brain by inhibiting microglia and NLRP3 activation and decreasing the production of inflammatory factors and the number of dead neurons. CONCLUSION: TRQ exerts potent inhibitory effects on dengue encephalitis in vitro and in vivo by reducing DENV-2-induced microglial activation and subsequently decreasing the inflammatory response, thereby protecting neurons. These findings demonstrate the potential of TRQ in the treatment of dengue encephalitis.

2.
Exp Gerontol ; 182: 112305, 2023 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-37797916

RESUMO

Heart disease is a significant health concern for elderly individuals, with heart aging being the primary cause. Recent studies have shown that autophagy can play a protective role in preventing cardiac aging. Our previous research confirmed that Chikusetsu saponin IVa, a fundamental component of Saponins of Panax japonics (SPJ), can enhance basic autophagy levels in cardiomyocyte of isoproterenol induced cardiac fibrosis mice. However, it remains unclear whether SPJ possesses a protective effect on cardiac dysfunction during the natural aging process. Rats were randomly divided into four groups: adult control group (6 months old), aging group (24 months old), aging group treated with 10 mg/kg SPJ, and aging group treated with 30 mg/kg SPJ. The heart function, blood pressure, and heart mass index (HMI) were measured. Hematoxylin and eosin staining (H&E) and Wheat Germ Agglutinin (WGA) staining were used to observe the changes in morphology, while Masson staining was used to examine collagen deposition in the rat hearts and CD45 immunohistochemistry was conducted to examine the macrophage infiltration in heart tissues. TUNEL kit was used to detect apoptosis level of cardiomyocyte, and western blot was used to evaluate autophagy-related proteins as well as AMPK/mTOR/ULK1 pathway-related markers. SPJ treatment improved the cardiac function, reduced HMI, attenuated myocardial fiber disorder, inhibited inflammatory cell infiltration, and decreased collagen deposition and cardiomyocyte apoptosis in aging rats. Additionally, SPJ treatment decreased the expression of aging-related proteins and restored the expression of autophagy-related markers. SPJ activated autophagy through the activation of AMPK, which in turn increased the phosphorylation of ULK1(Ser555), while inhibited the phosphorylation of mTOR and ULK1(Ser757). Our study demonstrates that SPJ improves the cardiac function of aging rats by enhancing basal autophagy through the AMPK/mTOR/ULK1 pathway. These results offer a theoretical foundation and empirical evidence to support the clinical advancement of SPJ in enhancing age-related cardiac dysfunction.


Assuntos
Cardiomiopatias , Panax , Saponinas , Humanos , Ratos , Camundongos , Animais , Idoso , Proteínas Quinases Ativadas por AMP/metabolismo , Panax/metabolismo , Miócitos Cardíacos , Serina-Treonina Quinases TOR/metabolismo , Envelhecimento/metabolismo , Saponinas/farmacologia , Autofagia , Colágeno , Proteína Homóloga à Proteína-1 Relacionada à Autofagia/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular
3.
Materials (Basel) ; 16(16)2023 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-37629821

RESUMO

High-entropy alloys (HEAs) have shown promising potential applications in advanced reactors due to the outstanding mechanical properties and irradiation tolerance at elevated temperatures. In this work, the novel low-activation Ti2ZrHfxV0.5Ta0.2 HEAs were designed and prepared to explore high-performance HEAs under irradiation. The microstructures and mechanical properties of the Ti2ZrHfxV0.5Ta0.2 HEAs before and after irradiation were investigated. The results showed that the unirradiated Ti2ZrHfxV0.5Ta0.2 HEAs displayed a single-phase BCC structure. The yield strength of the Ti2ZrHfxV0.5Ta0.2 HEAs increased gradually with the increase of Hf content without decreasing the plasticity at room and elevated temperatures. After irradiation, no obvious radiation-induced segregations or precipitations were found in the transmission electron microscope results of the representative Ti2ZrHfV0.5Ta0.2 HEA. The size and number density of the He bubbles in the Ti2ZrHfV0.5Ta0.2 HEA increased with the improvement of fluence at 1023 K. At the fluences of 1 × 1016 and 3 × 1016 ions/cm2, the irradiation hardening fractions of the Ti2ZrHfV0.5Ta0.2 HEA were 17.7% and 34.1%, respectively, which were lower than those of most reported conventional low-activation materials at similar He ion irradiation fluences. The Ti2ZrHfV0.5Ta0.2 HEA showed good comprehensive mechanical properties, structural stability, and irradiation hardening resistance at elevated temperatures, making it a promising structural material candidate for advanced nuclear energy systems.

4.
Lab Med ; 54(6): 608-612, 2023 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-37027310

RESUMO

OBJECTIVE: In this study, the association between preoperative levels of serum liver enzymes and overall survival (OS) was evaluated in patients with resectable pancreatic cancer. METHODS: Preoperative serum levels of alanine aminotransferase (ALT), aspartate aminotransferases (AST), γ-glutamyltransferase, alkaline phosphatase, and lactate dehydrogenase of 101 patients with pancreatic ductal adenocarcinoma (PDAC) were collected. Univariate and multivariate Cox hazard models were used to identify independent variables associated with OS in this cohort. RESULTS: Patients with elevated AST levels had significantly worse OS than patients with lower AST levels. A nomogram was created using TNM staging and AST levels and was shown to be more accurate in prediction than the American Joint Committee on Cancer 8th edition standard method. CONCLUSION: Preoperative AST levels could be a novel independent prognostic biomarker for patients with PDAC. The incorporation of AST levels into a nomogram with TNM staging can be an accurate predictive model for OS in patients with resectable PDAC.


Assuntos
Adenocarcinoma , Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Prognóstico , Aspartato Aminotransferases , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/cirurgia , Carcinoma Ductal Pancreático/diagnóstico , Carcinoma Ductal Pancreático/cirurgia , Estudos Retrospectivos , Neoplasias Pancreáticas
5.
J Ethnopharmacol ; 309: 116339, 2023 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-36870463

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Dengue virus (DENV) infection is a global public health issue without effective therapeutic interventions. Chinese medicine with heat-clearing and detoxifying properties has been frequently used in the treatment of viral infection. Ampelopsis Radix (AR) is a traditional Chinese medicine for clearing heat and detoxification that has been widely used in the prevention and treatment of infectious diseases. However, no studies on the effects of AR against viral infection have been reported, thus far. AIM OF THE STUDY: To explore the anti-DENV activities of the fraction (AR-1) obtained from AR both in vitro and in vivo. MATERIALS AND METHODS: The chemical composition of AR-1 was identified by liquid chromatography-tandem MS (LC‒MS/MS). The antiviral activities of AR-1 were studied in baby hamster kidney fibroblast BHK-21 cells, ICR suckling mice and induction of interferon α/ß (IFN-α/ß) and IFN-γ R-/- (AG129) mice. RESULTS: Based on LC‒MS/MS analysis, 60 compounds (including flavonoids, phenols, anthraquinones, alkaloids and other types) were tentatively characterized from AR-1. AR-1 inhibited the cytopathic effect, the production of progeny virus and the synthesis of viral RNA and proteins by blocking DENV-2 binding to BHK-21 cells. Moreover, AR-1 significantly attenuated weight loss, decreased clinical scores and prolonged the survival of DENV-infected ICR suckling mice. Critically, the viral load in blood, brain and kidney tissues and the pathological changes in brain were remarkably alleviated after AR-1 treatment. Further study on AG129 mice showed that AR-1 obviously improved the clinical manifestations and survival rate, reduced viremia, attenuated gastric distension and relieved the pathological lesions caused by DENV. CONCLUSIONS: In summary, this is the first report that AR-1 exhibits anti-DENV effects both in vitro and in vivo, which suggests that AR-1 may be developed as a therapeutic candidate against DENV infection.


Assuntos
Ampelopsis , Animais , Camundongos , Cromatografia Líquida , Camundongos Endogâmicos ICR , Espectrometria de Massas em Tandem , Antivirais/farmacologia , Antivirais/uso terapêutico , Replicação Viral
6.
Biomed Chromatogr ; 37(3): e5565, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36515658

RESUMO

Shenmai Injection (SMI), which tonifies Qi and prevents exhaustion, nourishes Yin and generates body fluid, is usually used in the treatment of shock with deficiency of Qi and Yin, coronary artery disease, viral myocarditis, granulocytopenia and chronic pulmonary heart disease clinically. Ginsenosides Rg1 and Rb1 are the main active ingredients of SMI. In this study, high-performance liquid chromatography tandem mass spectrometry methods for quantification of Rb1 and Rg1 in beagle dogs were developed and validated according to international regulatory guidelines. The methods were applied to measure the pharmacokinetics parameters of the two ginsenoside after intravenous administration. The linear ranges of the analytes were 3.9-1,000 ng/ml for Rg1 and Rb1. After injection of single and multiple doses of SMI (1 ml/kg), the plasma concentration-time profiles of Rg1 and Rb1 met the characteristics of one-compartment and typical two-compartment intravenous injection.


Assuntos
Medicamentos de Ervas Chinesas , Ginsenosídeos , Cães , Animais , Ginsenosídeos/farmacocinética , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas em Tandem , Medicamentos de Ervas Chinesas/farmacocinética , Administração Intravenosa
7.
Mol Med Rep ; 23(6)2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33846783

RESUMO

The primary pathological changes observed in osteoarthritis (OA) involve inflammation and degeneration of chondrocytes. 3­phosphoglycerate dehydrogenase (Phgdh), a rate­limiting enzyme involved in the conversion of 3­phosphoglycerate to serine, serves as a crucial molecular component of cell growth and metabolism. However, its effects on chondrocytes in OA have not been determined. In the present study, a rat model of OA was used to investigate the expression levels of Phgdh in vivo and in vitro. Additionally, the role of Phgdh in extracellular matrix (ECM) synthesis, inflammation, apoptosis and oxidative stress levels of chondrocytes was detected in vitro. Phgdh expression was decreased in OA, and Phgdh overexpression promoted ECM synthesis, decreased levels inflammatory cytokines, such as Il­6, TNF­α, a disintegrin and metalloproteinase with thrombospondin motifs 5 and MMP13, and decreased apoptosis. Furthermore, expression of Phgdh effectively increased expression levels of the cellular antioxidant enzymes catalase and superoxide dismutase 1, and decreased the levels of reactive oxygen species in chondrocytes; and this may have been regulated by a Kelch like ECH associated protein 1/nuclear factor erythroid 2­related factor 2 axis. Taken together, these results suggest that Phgdh may be used to manage the progression of OA.


Assuntos
Condrócitos/metabolismo , Inflamação/metabolismo , Interleucina-1beta/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Fosfoglicerato Desidrogenase/metabolismo , Fosfoglicerato Desidrogenase/farmacologia , Animais , Apoptose/efeitos dos fármacos , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Masculino , Metaloproteinase 13 da Matriz/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Osteoartrite/metabolismo , Fosfoglicerato Desidrogenase/genética , Ratos , Fator de Necrose Tumoral alfa/metabolismo
8.
Clin Sci (Lond) ; 134(18): 2453-2467, 2020 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-32940654

RESUMO

Hypertensive patients have impaired sodium excretion. However, the mechanisms are incompletely understood. Despite the established association between obesity/excess adiposity and hypertension, whether and how adiponectin, one of the adipokines, contributes to impaired sodium excretion in hypertension has not been previously investigated. The current study tested the hypothesis that adiponectin promotes natriuresis and diuresis in the normotensive state. However, impaired adiponectin-mediated natriuresis and diuresis are involved in pathogenesis of hypertension. We found that sodium excretion was reduced in adiponectin knockout (Adipo-/-) mice; intrarenal arterial infusion of adiponectin-induced natriuresis and diuresis in Wistar-Kyoto (WKY) rats. However, the natriuretic and diuretic effects of adiponectin were impaired in spontaneously hypertensive rats (SHRs), which were ascribed to the hyperphosphorylation of adiponectin receptor and subsequent uncoupling from Gαi. Inhibition of adiponectin receptor phosphorylation by a specific point mutation restored its coupling with Gαi and the adiponectin-mediated inhibition of Na+-K+-ATPase activity in renal proximal tubule (RPT) cells from SHRs. Finally, we identified G protein-coupled receptor kinase 4 (GRK4) as a mediator of adiponectin receptor hyperphosphorylation; mice transgenic for a hyperphosphorylating variant of GRK4 replicated the abnormal adiponectin function observed in SHRs, whereas down-regulation of GRK4 by renal ultrasound-directed small interfering RNA (siRNA) restored the adiponectin-mediated sodium excretion and reduced the blood pressure in SHRs. We conclude that the stimulatory effect of adiponectin on sodium excretion is impaired in hypertension, which is ascribed to the increased renal GRK4 expression and activity. Targeting GRK4 restores impaired adiponectin-mediated sodium excretion in hypertension, thus representing a novel strategy against hypertension.


Assuntos
Quinase 4 de Receptor Acoplado a Proteína G/metabolismo , Hipertensão/metabolismo , Rim/metabolismo , Receptores de Adiponectina/metabolismo , Sódio/metabolismo , Adiponectina/metabolismo , Animais , Pressão Sanguínea , Linhagem Celular , Diurese , Subunidades alfa Gi-Go de Proteínas de Ligação ao GTP/metabolismo , Hipertensão/fisiopatologia , Camundongos Transgênicos , Mutação/genética , Natriurese , Fosforilação , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY
9.
J Pharm Biomed Anal ; 189: 113411, 2020 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-32603924

RESUMO

ShengMai Formula (SMF), a famous traditional Chinese medicine (TCM) formula, has been extensively used for treating the diseases caused by Qi-Yin deficiency for almost 1000 years. However, few studies are elucidated about its batch-to-batch quality control system and the quality control markers remain largely unrevealed, which have hindered the development and utilization of SMF. In this study, we aimed to screen the optimal quality control markers to evaluate the overall quality consistency of SMF. High-performance liquid chromatography (HPLC) fingerprint coupled with similarity analysis (SA), principal components analysis (PCA) and hierarchical cluster analysis (HCA) was firstly established to hunt for the discriminant components that resulting in the chemical inconsistence among different batches of SMF. Subsequently, different batches of samples were selected to explore their immunomodulatory activities by neutral red method, Cell Counting Kit-8 (CCK-8) assay and enzyme-linked immunosorbent assay (ELISA). Finally, the fingerprint-efficacy relationships were further illuminated to discover the major bioactive compositions using grey relational analysis (GRA), partial least squares regression (PLSR) analysis and artificial neural network (ANN) analysis. As a result, schisandrol A, schisandrol B, methylophiopogonanone A, schisandrin B, ginsenoside Rf, ginsenoside Rb1, ginsenoside Rg2 and ginsenoside Rb2 were selected as the quality control markers and thus their simultaneous quantification was performed to both evaluate the batch-to-batch chemical and bioactive consistency among different batches of SMF. Our investigation not only stresses the necessity of consistency in efficacy besides chemical consistency, but also provides a comprehensive and powerful quality assessment approach, which is promising to monitor the overall quality consistency of SMF.


Assuntos
Medicamentos de Ervas Chinesas , Cromatografia Líquida de Alta Pressão , Combinação de Medicamentos , Medicina Tradicional Chinesa , Controle de Qualidade
10.
J Ethnopharmacol ; 263: 113145, 2020 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-32730890

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Qingwen Baidu Decoction (QBD), a famous traditional Chinese medicine prescription with heat-clearing and detoxifying efficacies, is widely used in the treatment of inflammatory diseases. However, due to lack of holistic quality evaluation research, the further study on the detailed molecular mechanisms of action are still insufficient. AIM OF THE STUDY: This study aimed to evaluate the overall quality of QBD and to explore the anti-inflammatory effects and associated intracellular signaling pathways. MATERIALS AND METHODS: a comprehensive method of chemical fingerprint analysis and simultaneous multi-component quantification was firstly developed by high performance liquid chromatography with diode array detector (HPLC-DAD). Similarity analysis, principal component analysis and hierarchical cluster analysis with heatmap were also applied to screen out the markers components in QBD samples. Moreover, its anti-inflammatory effects and mechanisms were further investigated by survival analysis, hematoxylin-eosin staining (H&E), neutrophil observation, quantitative real-time PCR analysis (qRT-PCR), Western blotting and confocal microscopy. RESULTS: Twenty-one characteristic peaks from 11 herbs were chemically identified in the chromatographic fingerprint. Fifteen quantitative markers from 11 herbs, such as baicalin, wogonoside, geniposidic acid, oxypaeoniflora and so on, were screened out with the aid of chemometrics to further quantitatively assess the quality of QBD. The results of survival analysis, H&E and neutrophil observation in zebrafish inflammatory models consistently showed that QBD exerts potent anti-inflammatory effects in a dose-dependent manner. Additionally, QBD inhibited the activation of NF-κB and STAT3 signal pathways in LPS-induced zebrafish and RAW 264.7 macrophage cells. CONCLUSION: Collectively, our investigations firstly described the chemical profile of QBD and its possible mechanism of anti-inflammation, which provides a preferred strategy for monitoring the overall quality of QBD and supports its clinical application in treating inflammation-related diseases.


Assuntos
Anti-Inflamatórios/análise , Anti-Inflamatórios/uso terapêutico , Medicamentos de Ervas Chinesas/análise , Medicamentos de Ervas Chinesas/uso terapêutico , Saúde Holística , Animais , Animais Geneticamente Modificados , Cromatografia Líquida de Alta Pressão/normas , Avaliação Pré-Clínica de Medicamentos/métodos , Saúde Holística/etnologia , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Camundongos , Células RAW 264.7 , Reprodutibilidade dos Testes , Peixe-Zebra
11.
Materials (Basel) ; 13(14)2020 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-32674338

RESUMO

The Hastelloy N alloy, Alloy 800H and 316H stainless steel were irradiated by Xe20+ ion irradiation with energy of 4 MeV at room temperature (peak damage ranging from 0.5 to 10 dpa). The micromechanical properties, hardness and creep plasticity, of these three investigated alloys were characterized before and after irradiation using nanoindentation. The results show that the hardness increases, and creep plasticity degrades with increasing ion dose in all the samples. In comparison, Hastelloy N has good irradiation damage resistance, while that of the 800H and 316H alloys is slightly worse. Additionally, the approximate positive relationship between irradiation hardening and creep plasticity degradation means that the property of creep plasticity of irradiated materials can be reflected from the nanohardness measurement for the heavy ion irradiation cases.

12.
Medicine (Baltimore) ; 98(9): e14761, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30817635

RESUMO

BACKGROUND: Sepsis is the most common critical illness in the clinic, with a high incidence and mortality. Qingwen Baidu decoction (QWBDD) has been widely applied in the treatment of sepsis, however, there is no systematic review or meta-analysis of QWBDD in the treatment of sepsis. Hence, we provide a protocol of systematic review and meta-analysis to evaluate the efficacy and safety of QWBDD in the treatment of sepsis. METHODS: The databases including Cochrane Library, PubMed, Embase, Web of Science, Cochrane Clinical Trial Database, World Health Organization International Clinical Trial Registration Platform, CNKI, CBM, VIP, and WanFang Database will be searched from the time when the respective databases were established to January 2019. All randomized controlled trials (RTCs) published in Chinese and English assessing QWBDD for sepsis will be included. Continuity data are expressed as mean difference (MD) or standard mean difference (SMD), and dichotomous data is expressed as relative risk. Analyses will be performed by using RevMan V.5.3.5 software. RESULTS: This study will provide high-quality synthesis of current evidence of QWBDD in the treatment of sepsis from the following aspects, including 28-day mortality, mean arterial pressure (MAP), blood lactate, procalcitonin (PCT), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), hypersensitive C-reactive protein (hs-CRP), acute physiology and chronic health score (APACHE-II), intensive care unit stay, mean hospital stay, mechanical ventilation time, etc. CONCLUSION:: Our systematic review will provide evidence for judging whether QWBDD is an effective intervention for sepsis. PROSPERO REGISTRATION NUMBER: PROSPERO CRD 42019123078.


Assuntos
Medicamentos de Ervas Chinesas/uso terapêutico , Projetos de Pesquisa , Sepse/tratamento farmacológico , APACHE , Pressão Arterial , Proteína C-Reativa/análise , Medicamentos de Ervas Chinesas/administração & dosagem , Medicamentos de Ervas Chinesas/efeitos adversos , Humanos , Unidades de Terapia Intensiva/estatística & dados numéricos , Interleucina-6/sangue , Ácido Láctico/sangue , Tempo de Internação , Pró-Calcitonina/sangue , Ensaios Clínicos Controlados Aleatórios como Assunto , Respiração Artificial , Fator de Necrose Tumoral alfa/sangue
13.
Materials (Basel) ; 10(4)2017 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-28772747

RESUMO

A new generation of alloys, which rely on a combination of various strengthening mechanisms, has been developed for application in molten salt nuclear reactors. In the current study, a battery of dispersion and precipitation-strengthened (DPS) NiMo-based alloys containing varying amounts of SiC (0.5-2.5 wt %) were prepared from Ni-Mo-SiC powder mixture via a mechanical alloying (MA) route followed by spark plasma sintering (SPS) and rapid cooling. Neutron Powder Diffraction (NPD), Electron Back Scattering Diffraction (EBSD), and Transmission Electron Microscopy (TEM) were employed in the characterization of the microstructural properties of these in-house prepared NiMo-SiC DPS alloys. The study showed that uniformly-dispersed SiC particles provide dispersion strengthening, the precipitation of nano-scale Ni3Si particles provides precipitation strengthening, and the solid-solution of Mo in the Ni matrix provides solid-solution strengthening. It was further shown that the milling time has significant effects on the microstructural characteristics of these alloys. Increased milling time seems to limit the grain growth of the NiMo matrix by producing well-dispersed Mo2C particles during sintering. The amount of grain boundaries greatly increases the Hall-Petch strengthening, resulting in significantly higher strength in the case of 48-h-milled NiMo-SiC DPS alloys compared with the 8-h-milled alloys. However, it was also shown that the total elongation is considerably reduced in the 48-h-milled NiMo-SiC DPS alloy due to high porosity. The porosity is a result of cold welding of the powder mixture during the extended milling process.

14.
Exp Ther Med ; 13(2): 437-442, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28352312

RESUMO

Geniposide is a water-soluble iridoid glucoside with anti-oxidant and anti-inflammatory biological functions. It has been indicated that geniposide may increase doxorubicin (DOX) accumulation in drug-resistant tumor cells. The present study aimed to investigate the resistance-reversing effect of geniposide in DOX-resistant cells and assess the underlying mechanisms of its action. The results revealed that geniposide itself weakly inhibited tumor cell growth. Furthermore, geniposide effectively reversed DOX resistance in a dose-dependent manner in human osteosarcoma DOX-resistant (MG63/DOX) cells. The action of geniposide was confirmed by increased accumulation of intracellular DOX detected in MG63/DOX cells. Notably, geniposide enhanced the efficacy of DOX against MG63/DOX cancer cell-derived xenografts in nude mice. To study the mechanism, intracellular accumulation of rhodamine 123 was measured using flow cytometry. At concentrations that reversed multidrug resistance (MDR), geniposide significantly downregulated P-glycoprotein (P-gp) expression. Therefore, geniposide reverses P-gp-mediated MDR by reducing the expression of P-gp and its transport function. The present study therefore indicated that geniposide may be administered in combination with conventional anti-neoplastic drugs to prevent MDR.

15.
BMC Complement Altern Med ; 16(1): 469, 2016 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-27846838

RESUMO

BACKGROUND: This study directly and dynamically investigated the effects of SL extract (i.e., a combination of Radix Salviae miltiorrhizae and Andrographis paniculata extract) on plaque progression in vivo by high resolution ultrasound biomicroscopy (UBM). METHODS: An atherosclerosis model was established by placing a perivascular collar on the right common carotid artery in apolipoprotein E-deficient (ApoE-/-) mice. Thickness, plaque area and local blood flow were observed by UBM, pathological changes were observed by histochemical staining, and lipid levels were measured by respective commercially available kits. RESULTS: Compared with the model group, the SL extract groups showed reduced wall thickness of the aortic arch (GC: P = 0.001, P = 0.002, and P < 0.001; LC: P < 0.001, P < 0.001, and P < 0.001; BC: P = 0.027, P = 0.017, and P = 0.003; respectively), which presented with retarded plaque progression of the cartoid artery with concordantly increased blood flow (P = 0.002 and P < 0.001) as visualized in vivo by UBM. Histological analysis confirmed the reduction of carotid atherosclerosis. CONCLUSIONS: The SL extract inhibited the formation of atherosclerotic plaques in an ApoE-/- mice model by UBM analysis, and did so by effects that ameliorated local blood flow and improved blood lipid levels.


Assuntos
Apolipoproteínas E/deficiência , Aterosclerose/tratamento farmacológico , Medicamentos de Ervas Chinesas/administração & dosagem , Andrographis/química , Animais , Aorta Torácica/diagnóstico por imagem , Aorta Torácica/metabolismo , Apolipoproteínas E/genética , Aterosclerose/diagnóstico por imagem , Aterosclerose/genética , Aterosclerose/metabolismo , Circulação Sanguínea , Modelos Animais de Doenças , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microscopia Acústica , Placa Aterosclerótica/diagnóstico por imagem , Placa Aterosclerótica/tratamento farmacológico , Placa Aterosclerótica/genética
16.
J Am Heart Assoc ; 5(10)2016 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-27792639

RESUMO

BACKGROUND: G protein-coupled receptor kinase type 4 (GRK4) plays a vital role in the long-term control of blood pressure (BP) and sodium excretion by regulating renal G protein-coupled receptor phosphorylation, including dopamine type 1 receptor (D1R). Ultrasound-targeted microbubble destruction (UTMD) is a promising method for gene delivery. Whether this method can deliver GRK4 small interfering RNA (siRNA) and lower BP is not known. METHODS AND RESULTS: BP, 24-hour sodium excretion, and urine volume were measured after UTMD-targeted GRK4 siRNA delivery to the kidney in spontaneously hypertensive rats. The expression levels of GRK4 and D1R were determined by immunoblotting. The phosphorylation of D1R was investigated using immunoprecipitation. The present study revealed that UTMD-mediated renal GRK4 siRNA delivery efficiently reduced GRK4 expression and lowered BP in spontaneously hypertensive rats, accompanied by increased sodium excretion. The increased sodium excretion might be accounted for by the UTMD regulation of D1R phosphorylation and function in spontaneously hypertensive rats. Further analysis showed that, although UTMD had no effect on D1R expression, it reduced D1R phosphorylation in spontaneously hypertensive rats kidneys and consequently increased D1R-mediated natriuresis and diuresis. CONCLUSIONS: Taken together, these study results indicate that UTMD-targeted GRK4 siRNA delivery to the kidney effectively reduces D1R phosphorylation by inhibiting renal GRK4 expression, improving D1R-mediated natriuresis and diuresis, and lowering BP, which may provide a promising novel strategy for gene therapy for hypertension.


Assuntos
Pressão Sanguínea/genética , Quinase 4 de Receptor Acoplado a Proteína G/genética , Técnicas de Silenciamento de Genes/métodos , Técnicas de Transferência de Genes , Receptores de Dopamina D1/metabolismo , Ondas Ultrassônicas , Animais , Regulação para Baixo , Quinase 4 de Receptor Acoplado a Proteína G/metabolismo , Rim , Masculino , Microbolhas , RNA Interferente Pequeno , Ratos , Ratos Endogâmicos SHR , Sódio/urina
17.
Exp Ther Med ; 11(6): 2413-2419, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27284329

RESUMO

The aim of the present study was to observe the effects of the Chinese herbal formula QHF (Q, Qingrejiedu; H, Huoxuehuayu; and F, Fuzhengguben) on the migration and invasion of hepatocellular carcinoma (HCC) HepG2 cells and to elucidate the potential molecular mechanisms involved. HepG2 cells were treated with various concentrations of QHF, and scratch and Transwell® migration assays were used to qualitatively analyze differences in the migration and invasion activity of these cells. Extracellular signal-regulated kinase (ERK), p38 and c-Jun N-terminal kinase (JNK) inhibitors were subsequently introduced in order to study the association between QHF and the invasion of HepG2 cells. The protein expression levels of the mitogen-activated protein kinase (MAPK) signaling pathway in HepG2 cells in the presence and absence of QHF were additionally determined using western blot analysis. The results showed that QHF significantly inhibited the proliferation of the HepG2 cells in a concentration-dependent manner, in addition to inhibiting cell movement, which reduced the ability of the cells to invade and migrate. Western blot analysis indicated that the effects of QHF on HCC HepG2 cells after 24 h were to significantly decrease the expression of phosphorylated- (p-)ERK and to increase the expression of p-p38 and p-JNK; however, the total quantity of ERK, p38 and JNK protein remained unchanged. The administration of an inhibitor of ERK altered p38 and JNK expression and promoted the anti-invasion effects of QHF, whereas p38 and JNK inhibitors only partially reversed this effect. The results of the present study indicate, therefore, that QHF is able to inhibit the migratory and invasive activity of HepG2 cells. A possible underlying mechanism involves the activation of the p38 and JNK MAPK signaling pathway and the attenuation of the ERK signaling pathway.

18.
Materials (Basel) ; 9(10)2016 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-28773952

RESUMO

This work reports on the evolution law of helium bubbles in Hastelloy N alloy on post-irradiation annealing conditions. After helium ion irradiation at room temperature and subsequent annealing at 600 °C (1 h), the transmission electron microscopy (TEM) micrograph indicates the presence of helium bubbles with size of 2 nm in the depth range of 0-300 nm. As for the sample further annealed at 850 °C (5 h), on one hand, a "Denuded Zone" (0-38 nm) with rare helium bubbles forms due to the decreased helium concentration. On the other hand, the "Ripening Zone" (38-108 nm) and "Coalescence Zone" (108-350 nm) with huge differences in size and separation of helium bubbles, caused by different coarsening rates, are observed. The mechanisms of "Ostwald ripening" and "migration and coalescence", experimentally proved in this work, may explain these observations.

19.
Zhongguo Zhong Yao Za Zhi ; 41(4): 722-727, 2016 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-28871700

RESUMO

To reveal the protective and anti-apoptosis effect of compound Ginkgo biloba granules on oxidative stress injury of human umbilical vein endothelial cells (HUVEC). Negative control group, H2O2 model group and 4 drug pretreatment groups (80, 160, 320, 640 mg• L⁻¹) were established. The cell proliferation, morphological changes in each group after oxidative stress injury was detected by MTT assay and through microscope observation respectively. The content of LDH, MDA, SOD and NO and SOD activity in supernatant were detected to judge the protection effect of the drugs on endothelial cells. The protective effect on HUVEC apoptosis was analyzed by Caspase-3 activity test and Annexin V-FITC/PI staining. Western blot was used to observe the expression of apoptosis-related proteins Bcl-2 and Bax. Results showed that 1 200 µmol• L⁻¹ H2O2 can induce oxidative stress injury in endothelial cells and reduce the cell survival rate; cell proliferation inhibition degree is positively correlated with the effect time of H2O2. Besides, 80, 160, 320 640 mg•L⁻¹ compound Ginkgo biloba granules can protect HUVEC from oxidative stress injury, recover the normal proliferation level of cells, improve their state, prohibit cell apoptosis, and can up-regulate and down-regulate the expression level of Bcl-2 and Bax respectively. In conclusion, compound G. biloba granules can protect HUVEC from the oxidative stress injury induced by H2O2, its mechanism may be correlated with inhibition of the mitochondrial apoptotic pathway in HUVEC.


Assuntos
Apoptose/efeitos dos fármacos , Ginkgo biloba/química , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/farmacologia , Substâncias Protetoras/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/citologia , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Peróxido de Hidrogênio/toxicidade , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Espécies Reativas de Oxigênio/metabolismo
20.
Zhongguo Zhong Yao Za Zhi ; 40(10): 1977-83, 2015 May.
Artigo em Chinês | MEDLINE | ID: mdl-26390659

RESUMO

The aim of this research is to investigate the protection of PM2.5 infected RAW264.7 cell by traditional Chinese medicine (TCM)--Shenlian(SL) extracts and to establish the damage model. We use cell growth, cell damage and oxidative stress related markers, and inflammatory cytokines as observation index to evaluate the protection of PM2.5 infected RAW264.7 by SL extract. The results showed that 50 mg x L(-1) PM2.5 could cause cell particle deposition, inhibit the growth of cells, and significantly increase the cell supernatant of LDH, NO release quantity and intracellular reactive oxygen species (ROS) level during 4 h and 24 h. In the intervention of SL extract 50, 25, 10 mg x L(-1), the particle deposition of RAW264.7 cells, cell supernatant of LDH, NO, IL(-1) beta release, MCP-1 was significantly decreased, the SOD activity increased significantly. It shows that SL extracts of PM2.5 infected RAW264.7 cell damage has obvious protective effect, the effect may be related to the direct protection of cells, reduce oxidative stress and inflammatory injury.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Macrófagos/efeitos dos fármacos , Material Particulado/toxicidade , Substâncias Protetoras/farmacologia , Animais , Linhagem Celular , Camundongos , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo
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