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1.
World J Clin Cases ; 7(20): 3335-3340, 2019 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-31667188

RESUMO

BACKGROUND: Acute chest pain (ACP) is very common among patients presenting to emergency departments. Nevertheless, ACP caused by esophageal foreign body is relatively rarely reported. CASE SUMMARY: A 56-year-old man suffering from chest pain (increased pain for the last 9 h) was admitted to our hospital on October 25, 2015. After undergoing physical examination and laboratory blood testing, he was diagnosed with acute anterior myocardial infarction. Consequently, the patient underwent emergency percutaneous coronary angiography; however, no myocardial infarction signs were observed. Later on, the patient experienced respiration failure and therefore was transferred to intensive care unit. Cardiac ultrasound showed pericardial effusion, which was considered as the cause of shock. He then underwent pericardium puncture drainage and the circulation temporarily improved. Nevertheless, persistent pericardial bleeding, unclear bleeding causes, and clot formation induced poor drainage led to worsening of cardiac tamponade symptoms. Consequently, the patient underwent emergency exploratory thoracotomy, which revealed a fish bone causing pericardial bleeding. The bone was removed, and the damaged blood vessels were mended. Eventually, the patient was discharged in good clinical condition. CONCLUSION: For patients with chest pain, it is necessary to consider the possibility of foreign body in the esophagus or even in the heart. Careful history taking and the corresponding inspection can help to avoid unnecessary damage and safeguard patients from unnecessary pain.

2.
Future Oncol ; 15(32): 3711-3721, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31664862

RESUMO

Aim: Circulation miRNAs have become increasingly appreciated in the diagnosis and prognosis of lung cancer. This study aims to identify and evaluate plasma miRNA-30a-5p as an early noninvasive biomarker for the diagnosis and prognosis of lung cancer. Pateints & methods: Expression levels of plasma miRNA 30a-5p were measured by quantitative real-time PCR. Receiver operating characteristic analysis and area under the curve were used to differentiate malignant from benign tumors and from healthy controls. Kaplan-Meier curves and Cox regression were used to determine survival and prognosis. Results: Our results suggest that the level of miRNA-30a-5p in plasma might be a considerable early novel noninvasive diagnostic and prognostic biomarker for lung cancer. Conclusion: Prospective studies must be performed to confirm this new early novel noninvasive diagnostic and prognostic biomarker for lung cancer.


Assuntos
Biomarcadores Tumorais/sangue , Neoplasias Pulmonares/diagnóstico , MicroRNAs/sangue , Biomarcadores Tumorais/genética , Estudos de Casos e Controles , Feminino , Expressão Gênica , Humanos , Estimativa de Kaplan-Meier , Neoplasias Pulmonares/sangue , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Masculino , MicroRNAs/genética , Pessoa de Meia-Idade , Análise Multivariada , Prognóstico , Estudos Prospectivos , Curva ROC
3.
Zool Res ; 39(1): 32-41, 2018 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-29511143

RESUMO

The Angolan strain of Marburg virus (MARV/Ang) can cause lethal disease in humans with a case fatality rate of up to 90%, but infection of immunocompetent rodents do not result in any observable symptoms. Our previous work includes the development and characterization of a MARV/Ang variant that can cause lethal disease in mice (MARV/Ang-MA), with the aim of using this tool to screen for promising prophylactic and therapeutic candidates. An intermediate animal model is needed to confirm any findings from mice studies before testing in the gold-standard non-human primate (NHP) model. In this study, we serially passaged the clinical isolate of MARV/Ang in the livers and spleens of guinea pigs until a variant emerged that causes 100% lethality in guinea pigs (MARV/Ang-GA). Animals infected with MARV/Ang-GA showed signs of filovirus infection including lymphocytopenia, thrombocytopenia, and high viremia leading to spread to major organs, including the liver, spleen, lungs, and kidneys. The MARV/Ang-GA guinea pigs died between 7-9 days after infection, and the LD50 was calculated to be 1.1×10-1 TCID50 (median tissue culture infective dose). Mutations in MARV/Ang-GA were identified and compared to sequences of known rodent-adapted MARV/Ang variants, which may benefit future studies characterizing important host adaptation sites in the MARV/Ang viral genome.


Assuntos
Doença do Vírus de Marburg/etiologia , Marburgvirus , Animais , Modelos Animais de Doenças , Feminino , Cobaias/virologia , Doença do Vírus de Marburg/patologia , Doença do Vírus de Marburg/virologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Carga Viral , Viremia/patologia , Viremia/virologia
4.
Biomed Chromatogr ; 30(3): 390-5, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26174138

RESUMO

A quantitative capillary electrophoresis (qCE) was developed by utilizing a rotary type of nano-volume injector, an autosampler, and a thermostat with cooling capacity. The accuracy and precision were greatly improved compared with conventional capillary electrophoresis. The 10 nL volume accuracy was guaranteed by the carefully designed nano-injector with an accurate internal loop. The system repeatability (precision) in terms of RSD <0.5% for migration time and 1% for peak area were achieved by using DMSO as a test sample. We believe that this fully automated qCE system has the potential to be employed broadly in quality control and quality assurance in the pharmaceutical industry.


Assuntos
Automação/métodos , Eletroforese Capilar/métodos , Automação/instrumentação , Eletroforese Capilar/instrumentação , Desenho de Equipamento , Nucleosídeos/análise , Reprodutibilidade dos Testes
5.
Acta Pharmacol Sin ; 36(9): 1065-73, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26279157

RESUMO

AIM: To investigate the effects of calcium and vitamin D supplementation on bone turnover marker levels, muscle strength and quality of life in postmenopausal Chinese women. METHODS: A total of 485 healthy postmenopausal Chinese women (63.44±5.04 years) were enrolled in this open-label, 2-year, prospective, community-based trial. The participants were divided into group A, B, C, which were treated with calcium (600 mg/d) alone, calcium (600 mg/d) and cholecalciferol (800 IU/d) or calcium (600 mg/d) and calcitriol (0.25 µg/d), respectively, for 2 years. Serum levels of 25-hydroxyvitamin D, parathyroid hormone, ß-CTX and P1NP were measured, and the muscle strength and quality of life were assessed at baseline and at 12- and 24-month follow-ups. RESULTS: Four hundred and sixty one participants completed this study. Serum levels of 25-hydroxyvitamin D were significantly increased in group C, but not changed in groups A and B at 24-month follow-up. Serum levels of parathyroid hormone, bone turnover marker ß-CTX and bone formation marker P1NP were significantly decreased in group C, while serum levels of ß-CTX were increased in group A at 24-month follow-up. The participants in group C maintained the grip strength, while those in groups A and B exhibited decreased grip strength at 24-month follow-up. The quality of life for the participants in groups B and C remained consistent, but that in group A was deteriorated at 24-month follow-up. CONCLUSION: Supplementation with calcitriol and calcium modifies the bone turnover marker levels, and maintains muscle strength and quality of life in postmenopausal Chinese women, whereas supplementation with cholecalciferol and calcium prevents aging-mediated deterioration in quality of life.


Assuntos
Calcitriol/farmacologia , Cálcio/farmacologia , Colecalciferol/farmacologia , Pós-Menopausa , Qualidade de Vida , Vitaminas/farmacologia , Idoso , Conservadores da Densidade Óssea/administração & dosagem , Conservadores da Densidade Óssea/farmacologia , Remodelação Óssea/efeitos dos fármacos , Calcitriol/administração & dosagem , Cálcio/administração & dosagem , China , Colecalciferol/administração & dosagem , Suplementos Nutricionais/análise , Feminino , Força da Mão , Humanos , Pessoa de Meia-Idade , Força Muscular/efeitos dos fármacos , Estudos Prospectivos , Vitamina D/análogos & derivados , Vitamina D/sangue , Vitaminas/administração & dosagem
6.
J Phys Chem B ; 119(33): 10673-81, 2015 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-26218325

RESUMO

Despite extensive efforts on studying the decomposition mechanism of HMX under extreme condition, an intrinsic understanding of mechanical and chemical response processes, inducing the initial chemical reaction, is not yet achieved. In this work, the microscopic dynamic response and initial decomposition of ß-HMX with (1 0 0) surface and molecular vacancy under shock condition, were explored by means of the self-consistent-charge density-functional tight-binding method (SCC-DFTB) in conjunction with multiscale shock technique (MSST). The evolutions of various bond lengths and charge transfers were analyzed to explore and understand the initial reaction mechanism of HMX. Our results discovered that the C-N bond close to major axes had less compression sensitivity and higher stretch activity. The charge was transferred mainly from the N-NO2 group along the minor axes and H atom to C atom during the early compression process. The first reaction of HMX primarily initiated with the fission of the molecular ring at the site of the C-N bond close to major axes. Further breaking of the molecular ring enhanced intermolecular interactions and promoted the cleavage of C-H and N-NO2 bonds. More significantly, the dynamic response behavior clearly depended on the angle between chemical bond and shock direction.

7.
Environ Toxicol Pharmacol ; 38(2): 562-9, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25194326

RESUMO

Residues of avermectin (AVM) drugs have toxic effects on non-target organisms. Analyses of cytochrome P450 enzymes are among the most frequently employed indicators in pharmacology and toxicology studies. In this study, the responses of cytochrome P450 enzymes and pathological changes in the liver and kidney tissues of King pigeons (Columba livia) following subchronic exposure to avermectin for 30, 60 and 90d were investigated. Dose- and time-dependent decreases in the activities of P450 enzymes (i.e., aminopyrine-N-demethylase, erythromycin N-demethylase, aniline 4-hydroxylase and NADPH-cytochrome C reductase) and down-regulation of the P450 and b5 contents were observed. The microscopic structures were clearly altered, the severity of these alterations increased with the concentration of AVM and the exposure time. These results imply that AVM can inhibit the P450 enzyme systems in the liver and kidney tissues of pigeons. This research provides insight into the safe use of AVM and a comprehensive evaluation of the toxicological effects of AVM in birds.


Assuntos
Anti-Helmínticos/toxicidade , Columbidae/metabolismo , Sistema Enzimático do Citocromo P-450/metabolismo , Poluentes Ambientais/toxicidade , Ivermectina/análogos & derivados , Rim/patologia , Fígado/patologia , Animais , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Ivermectina/toxicidade , Rim/citologia , Rim/enzimologia , Fígado/citologia , Fígado/enzimologia , Microssomos/efeitos dos fármacos , Microssomos/enzimologia , Fatores de Tempo
8.
Opt Express ; 22(12): 14803-11, 2014 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-24977575

RESUMO

A new scheme to generate an intense isolated few-cycle attosecond XUV pulse is demonstrated using particle-in-cell simulations. By use of unipolarlike or subcycle laser pulses irradiating a thin foil target, a strong transverse net current can be excited, which emits a few-cycle XUV pulse from the target rear side. The isolated pulse is ultrashort in the time domain with duration of several hundred attoseconds. The pulse also has a narrow bandwidth in the spectral domain compared to other XUV sources of high-order harmonics. It has most energy confined around the plasma frequency and no low-harmonic orders below the plasma frequency. It is also shown that XUV pulse of peak field strength up to 8 × 10(12) Vm(-1) can be produced. Without the need for pulse selecting and spectral filtering, such an intense few-cycle XUV pulse is better suited to a number of applications.

9.
Artigo em Chinês | MEDLINE | ID: mdl-24800570

RESUMO

OBJECTIVE: To explore the correlation between the levels of liver fibrosis and liver fibrosis biochemical parameters of advanced schistosomiasis patients. METHODS: A total of 48 advanced schistosomiasis patients were investigated and they were examined by the liver biopsy and B ultrasound imaging. At the same time, the liver fibrosis biochemical parameters, including glutamine transpeptidase (GGT), alkaline phosphatase (AKP), procollagen III (PC-III), collagen type IV (IV-C), hyaluronic acid (HA) and laminin (LN), were detected. The liver fibrosis levels were classified by the liver biopsy and B ultrasound imaging, respectively, and the correlation between the levels of liver fibrosis and liver fibrosis biochemical parameters were analyzed statistically. RESULTS: There was no correlation between the liver fibrosis levels classified by the liver biopsy and all the liver fibrosis biochemical parameters; there was a weak correlation between the liver fibrosis levels classified by the B ultrasound imaging and GGT, AKP, LN and PC-III, respectively; there was a significant correlation between the liver fibrosis levels classified by the B ultrasound imaging and HA and IV-C, respectively. CONCLUSIONS: B ultrasound examination is a better, noninvasive fibrosis inspection method. Liver fibrosis biochemical parameters combined with the B ultrasound examination may better reflect the overall condition of liver fibrosis.


Assuntos
Cirrose Hepática/patologia , Esquistossomose/complicações , Idoso , Idoso de 80 Anos ou mais , Fosfatase Alcalina/sangue , Biópsia , Colágeno Tipo IV/sangue , Feminino , Humanos , Ácido Hialurônico/sangue , Fígado/patologia , Cirrose Hepática/classificação , Cirrose Hepática/complicações , Cirrose Hepática/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Ultrassonografia
10.
Ecotoxicol Environ Saf ; 98: 74-81, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24138898

RESUMO

Extensive use of avermectin (AVM) can result in environment pollution, and it is important to evaluate the potential impact this antibiotic has on ecological systems. Few published literatures have discussed the liver injury mechanisms induced by AVM on birds. In this study, pigeons were exposed to feed containing AVM (0, 20, 40 and 60 mg/kg diet) for 30, 60, 90 days respectively. The results showed that AVM increased the number of apoptosis and the expression level of caspase-3, 8, fas mRNA in the liver of pigeons. Ultrastructural alterations, including mitochondrial damage and chromatin aggregation, become severe with increase exposure dose. Exposure to AVM induced significant changes in antioxidant enzyme {superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px)} activities and malondialdehyde (MDA) content, augmented protein carbonyl (PCO) content and DNA-protein crosslink (DPC) coefficient, in a concentration-dependent manner in the liver of pigeons. Our results show that AVM has toxic effect in pigeon liver, and the mechanism of injury caused by AVM is closely related to apoptosis and oxidative stress.


Assuntos
Antibacterianos/toxicidade , Columbidae/metabolismo , Ivermectina/análogos & derivados , Fígado/efeitos dos fármacos , Estresse Oxidativo , Animais , Antioxidantes/metabolismo , Apoptose , Caspase 3/metabolismo , Caspase 8/metabolismo , Dano ao DNA , Proteína Ligante Fas/metabolismo , Glutationa Peroxidase/metabolismo , Ivermectina/toxicidade , Fígado/citologia , Fígado/metabolismo , Malondialdeído/metabolismo , Mitocôndrias Hepáticas/efeitos dos fármacos , Mitocôndrias Hepáticas/ultraestrutura , Carbonilação Proteica , Superóxido Dismutase/metabolismo
11.
Artigo em Inglês | MEDLINE | ID: mdl-24032951

RESUMO

This paper reports that an initially opaque plasma foil, irradiated by a laser pulse with intensity below the self-induced transparency (SIT) threshold, will become transparent, if a flux of energetic electrons is present. Based on this phenomenon, named flux-induced transparency (FIT), an approach to obtaining ultrasharp-front laser pulses is proposed. With the presence of an energetic-electron flux generated by a p-polarized laser irradiating an overdense plasma foil from the rear side, the propagation of an s-polarized laser irradiating the front surface of the foil can be manipulated. The transmitted s-polarized laser pulse has an ultrasharp front which rises by three orders of magnitude within a few laser cycles. The profile of the transmitted pulse is tunable by controlling the time at which the energetic-electron flux arrives at the front surface.

12.
Ecotoxicology ; 22(8): 1241-54, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23943211

RESUMO

Avermectins (AVMs) are the active components of some insecticidal and nematicidal products used in agriculture and veterinary medicine for the prevention of parasitic diseases. Residues of AVM drugs or their metabolites in livestock feces have toxic effects on non-target aquatic and terrestrial organisms. In this study, oxidative stress responses and pathological changes on pigeon brain tissues and serum after subchronic exposure to AVM for 30, 60 and 90 days were investigated. The decrease in antioxidant enzyme (superoxide dismutase, SOD and glutathione peroxidase, GSH-Px) activities and increase in methane dicarboxylic aldehyde content in a dose-time-dependent manner in the brain and serum of pigeon were observed. The protein carbonyl content, an indicator of protein oxidation, and DNA-protein crosslink coefficient were significantly augmented with dose-time-dependent properties. The microscopic structures of the cerebrum, cerebellum and optic lobe altered obviously, the severity of which increased with the concentration of AVM and exposure time. The results imply that AVM could induce oxidative damage to the brain tissue and serum of pigeon. The information presented in this study is helpful to understand the mechanism of AVM-induced oxidative stress in birds.


Assuntos
Encéfalo/efeitos dos fármacos , Columbidae/anormalidades , Inseticidas/toxicidade , Ivermectina/análogos & derivados , Estresse Oxidativo/efeitos dos fármacos , Animais , Antioxidantes/metabolismo , Encéfalo/patologia , Relação Dose-Resposta a Droga , Glutationa Peroxidase/metabolismo , Ivermectina/toxicidade , Carbonilação Proteica , Superóxido Dismutase/metabolismo
13.
Crit Care ; 17(3): 438, 2013 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-23805783

RESUMO

H7N9 influenza is a new emerging infection and has high mortality. Both chest radiography and computed tomography (CT) had some limitations in assessing such patients. We performed daily lung ultrasound in a patient with H7N9 influenza. Lung ultrasound and lung ultrasound score showed high consistency with CT and the progression of pneumonia. Ultrasound can be adjutant to chest radiography and CT in caring for patients with H7N9 influenza.


Assuntos
Subtipo H7N9 do Vírus da Influenza A/isolamento & purificação , Influenza Humana/diagnóstico por imagem , Lesão Pulmonar/diagnóstico por imagem , Feminino , Humanos , Influenza Humana/complicações , Lesão Pulmonar/etiologia , Lesão Pulmonar/virologia , Pessoa de Meia-Idade , Ultrassonografia
14.
Ecotoxicol Environ Saf ; 94: 28-36, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23702303

RESUMO

Chlorpyrifos (CPF) and atrazine (ATR) are the most widely used organophosphate insecticides and triazine herbicides, respectively, worldwide. This study aimed at investigating the effects of ATR, CPF and mixture on common carp gills following 40-d exposure and 40-d recovery experiments. Cytochrome P450 content, activities of aminopyrine N-demethylase (APND) and erythromycin N-demethylase (ERND) and the mRNA levels of the CYP1 family (CYP1A, CYP1B, and CYP1C) were determined. In total, 220 common carps were divided into eleven groups, and each group was treated with a specific concentration of ATR (4.28, 42.8 and 428 µg/L), CPF (1.16, 11.6 and 116 µg/L) or ATR-CPF mixture (1.13, 11.3 and 113 µg/L). The results showed that P450 content and activities of APND and ERND in fish exposed to ATR and mixture were significantly higher than those in the control group. After the 40-d recovery treatment (i.e., depuration), the P450 content and the activities of APND and ERND in fish decreased to the background levels. A similar tendency was also found in the mRNA levels of the CYP1 family (CYP1A, CYP1B, and CYP1C) in common carp gills. The CPF-treated fish showed no significant difference from the control groups, except for a significant CYP1C induction. These results indicated that CYP enzyme levels are induced by ATR but were only slightly affected by CPF in common carp gills. In addition, the ATR and CPF exposure showed an antagonistic effect on P450 enzymes in common carp gills.


Assuntos
Atrazina/toxicidade , Clorpirifos/toxicidade , Sistema Enzimático do Citocromo P-450/metabolismo , Brânquias/metabolismo , Herbicidas/toxicidade , Inseticidas/toxicidade , Aminopirina N-Desmetilase/genética , Aminopirina N-Desmetilase/metabolismo , Animais , Carpas/fisiologia , Citocromo P-450 CYP3A/metabolismo , Sistema Enzimático do Citocromo P-450/genética , Brânquias/efeitos dos fármacos , Brânquias/enzimologia , RNA Mensageiro/metabolismo , Poluentes Químicos da Água/toxicidade
15.
Parasitol Int ; 62(3): 283-8, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23466574

RESUMO

BACKGROUND: Schistosoma japonicum causes marked liver fibrosis, while lethal syndromes present in advanced schistosomiasis patients. Its management depends on the degree of fibrosis present. PATIENTS AND METHODS: Fifty-two patients were recruited to assess the diagnostic value of bio-markers in patients with advanced schistosomiasis japonica. Fibrosis was assessed in liver biopsies using METAVIR system. The correlation between conventional parameters and significant fibrosis (F2-F4) was assessed using univariate analysis and logistic regression. The method of area under receiver operating characteristic curves (AUROCs) was used as a measurement of diagnostic efficacy. RESULTS: White blood cell counts, platelet counts and albumin (all P<0.05) were significantly lower, while prothrombin time, international normalized ratio (INR), hyaluronic acid (HA), IV collagen and ultrasound fibrosis scores (all P<0.01) were significantly elevated in F2-F4 patients compared with F0-F1 patients. HA and INR were identified as independent predictors by multivariate analysis (P=0.023 and P=0.013, respectively). Of the routine laboratory tests for the diagnosis of significant fibrosis, HA gave the best AUROC of 0.875 (95% confidence interval (CI): 0.701-0.997). We constructed a new simple index (INR×HA/100) to discriminate between F2-F4 patients and F0-F1 patients. It showed the highest AUROC of 0.921 (95% CI: 0.828-1.000), and had better diagnostic values than APRI and FIB-4. CONCLUSION: HA and INR were reliable markers for differentiating significant liver fibrosis in patients with advanced schistosomiasis japonica. And the new simple index can easily predict significant liver fibrosis with a high degree of accuracy.


Assuntos
Cirrose Hepática/diagnóstico , Schistosoma japonicum/fisiologia , Esquistossomose Japônica/complicações , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Área Sob a Curva , Biomarcadores/sangue , Biópsia , Demografia , Feminino , Humanos , Ácido Hialurônico/análise , Coeficiente Internacional Normatizado , Fígado/patologia , Cirrose Hepática/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Curva ROC , Reprodutibilidade dos Testes , Esquistossomose Japônica/diagnóstico , Sensibilidade e Especificidade , Índice de Gravidade de Doença , Fatores de Tempo , Ultrassonografia
16.
Anticancer Agents Med Chem ; 13(2): 195-8, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22934692

RESUMO

Actinidia chinensis Planch. is a famous Chinese herbal medicine to treat many diseases such as cancers. Triterpenes, polyphenols and anthraquinones are normally considered as the main constituents for its effects. In this study, eleven known triterpenes were isolated from the root of Actinidia chinensis., and were examined for its antiangiogenic activities. Their structures were elucidated by comprehensive spectroscopic methods, including IR, UV, HR-ESI-MS, and 1D and 2D NMR techniques. The eleven compounds are following: 2α,3α,19-trihydroxyurs-12-en-28-oic acid (1), 2α,3ß-dihydroxyurs-12-en-28-oic acid (2), 2α,3α,23-trihydroxyurs-12-en-28-oic acid (3), asiatic acid (4), ursolic acid (5), 2α,3ß,19,24-tetrahydroxyurs-12-en-28-oic acid (6), 2α,3ß,19-trihydroxyolean-12-en-28-oic acid (7), 2α,3α,24-trihydroxyolean-12-en-28-oic acid (8), oleanolic acid (9), 3ß-O-acetyloleanolic acid (10), 2α,23-dihydroxylmicromeric acid (11). All these compounds were evaluated with respect to their antiangiogenic activities utilizing the assays of human umbilical vein endothelial cells (HUVEC) proliferation and tube formation and Ursolic acid (used as control) and compounds 2, 3, 4, and 8 exhibited significant, dose-dependently, antiangiogenic activity in the tested concentration range. Our findings suggest that antitumor action of Actinidia chinensis Planch. is partly via inhibiting tumor angiogenesis by triterpenes, and compounds 2, 3, 4, and 8 as the novel potential antiangiogenic agents are worthy of further translational research.


Assuntos
Inibidores da Angiogênese/farmacologia , Medicina Tradicional Chinesa , Plantas Medicinais/química , Triterpenos/farmacologia , Inibidores da Angiogênese/química , Inibidores da Angiogênese/isolamento & purificação , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Humanos , Conformação Molecular , Relação Estrutura-Atividade , Triterpenos/química , Triterpenos/isolamento & purificação
17.
Molecules ; 17(4): 4474-83, 2012 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-22504832

RESUMO

Two new polyketides: 2Z-(heptadec-12-enyl)-4-hydroxy-3,4,7,8-tetrahydro-2H-chromen-5(6H)-one (1) and 2-(heptadec-12-enyl)-5-hydroxy-5,6,7,8-tetrahydrochromen- 4-one (2), together with eleven known compounds: 4-hydroxy-2-[(3,4-methylenedioxy- phenyl)tridecanoyl] cyclohexane-1,3-dione (3), oleiferinone (4), 4-hydroxy-2-[(3,4- methylenedioxyphenyl)undecanoyl]cyclohexane-1,3-dione (5), 4-hydroxy-2-[(11-phenyl- undecanoyl)cyclohexane-1,3-dione (6), proctorione C (7), surinone C (8), 5-hydroxy- 7,8,4'-trimethoxyflavone (9), 5-hydroxy-7,8,3',4'-tetramethoxyflavone (10), 5-hydroxy- 7,3',4'-trimethoxyflavone (11), 5,8-dihydroxy-7,3',4'-trimethoxyflavone (12) and cepharanone B (13) were isolated from the whole plant of Peperomia dindygulensis Miq. Their structures were elucidated by spectroscopic methods, including 2D-NMR techniques. Compounds 2, 3, 5 and 8 inhibited human umbilical vein endothelial cell (HUVEC) proliferation and compounds 5 and 8 sharply suppressed HUVEC tube formation.


Assuntos
Inibidores da Angiogênese/farmacologia , Policetídeos/farmacologia , Inibidores da Angiogênese/química , Inibidores da Angiogênese/isolamento & purificação , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Humanos , Ressonância Magnética Nuclear Biomolecular , Peperomia/química , Policetídeos/química , Policetídeos/isolamento & purificação
18.
Chem Biodivers ; 8(5): 862-71, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21560234

RESUMO

Two new secolignans, peperomins G and H (1 and 2, resp.), were isolated from the whole plant of Peperomia dindygulensis, together with five known secolignans, peperomin A (3), peperomin E (4), peperomin B (5), 2,3-trans-2-methyl-3-{(3-hydroxy-4,5-dimethoxyphenyl)[5-methoxy-3,4-(methylenedioxy)phenyl]methyl}butyrolactone (6), 2,3-cis-2-(hydroxymethyl)-3-{bis[5-methoxy-3,4-(methylenedioxy)phenyl]methyl}butyrolactone (7). Their structures and configurations were elucidated by spectroscopic methods including 2D-NMR techniques. Antiangiogenic effects of all compounds were evaluated using human umbilical vein endothelial cells (HUVEC) proliferation and tube-formation tests, with compounds 4 and 5 being active in the bioassay. Compounds 4 and 5 induced obvious cell toxicity to HUVEC with IC(50) values of 1.64±0.19 and 8.44±0.4 µM, respectively. Compounds 4 and 5 also exhibited significant HUVEC tube formation-inhibiting activity with IC(50) values of 3.13±0.09 and 6.24±0.12 µM, respectively.


Assuntos
Inibidores da Angiogênese/química , Inibidores da Angiogênese/farmacologia , Células Endoteliais/efeitos dos fármacos , Lignanas/química , Lignanas/farmacologia , Peperomia/química , Inibidores da Angiogênese/isolamento & purificação , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Células Endoteliais/citologia , Humanos , Lignanas/isolamento & purificação , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia
19.
Phys Rev E Stat Nonlin Soft Matter Phys ; 83(4 Pt 2): 046404, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21599313

RESUMO

The possibility of enhancing inner-shell x-ray emission, especially Kα emission, by femtosecond-laser irradiation of solid cones instead of foils was investigated theoretically. In a model for hot electron (HE) transport and Kα x-ray generation, Kα emission from laser-irradiated solid cones and foils is investigated. As a complementarity to the model, the contributions from electric and magnetic fields generated by the HE current in solid cones and foils are discussed. The results indicate that the efficiency of HE energy conversion to Kα photons is improved and the optimum HE temperature is increased.

20.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 25(3): 295-8, 2007 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-17629212

RESUMO

OBJECTIVE: To evaluate mechanical properties of zirconia toughened composite alumina (ZTCA) ceramic used for dental application, characterize the effect of different zirconia contents on mechanical properties of ZTCA. METHODS: Dental alumina ceramic powder was prepared by sol-gel method, and four groups of ZTCA powders with different zirconia contents were prepared via surface-induced precipitation method. All five groups of powders were dry-pressed and then sintered to make standard specimens for mechanical tests. The flexural strength and fracture toughness of these specimens were evaluated, and the fractography was characterized by scanning electronic microscope (SEM). Phases of ZTCA were also determined using X-ray diffraction (XRD). RESULTS: It was found that the flexural strength of ZTCA ceramics increases with ZrO2 content up to 30%, and decreases thereafter. ZTCA specimens containing 30% ZrO2 show the highest flexural strength, and the corresponding fracture toughness was 1.85 MPa x m(1/2). The XRD results of ZTCA ceramics showed the phase constituents of alpha-Al2O3, t-ZrO2 and a small amount of m-ZrO2. CONCLUSION: The strengthening and toughening mechanisms of ZTCA depend on ZrO2 content. In the range of 15%-30% ZrO2, the stress-induced phase transformation toughening mechanism is dominant, while microcrack and deflection exist as the additional toughening mechanism when ZrO2 addition amount is above 30%.


Assuntos
Óxido de Alumínio , Cerâmica , Porcelana Dentária , Teste de Materiais , Zircônio
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