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1.
Acad Radiol ; 31(4): 1326-1335, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37863778

RESUMO

RATIONALE AND OBJECTIVES: This study aimed to evaluate the technical success rate and stiffness measurement reliability of two specific hepatic magnetic resonance elastography (MRE) sequences dedicated to solving susceptibility artifacts in patients with various degrees of hepatic iron overload. MATERIALS AND METHODS: Thirty-seven patients with iron-overloaded liver confirmed by R2* value measurement who underwent two-dimensional (2D) spin-echo (SE) MRE and 2D SE-echo-planar-imaging (EPI) MRE were reviewed retrospectively. According to four categories based on R2* value (mild, moderate, severe elevation, and extremely severe iron overload), we compared the success rate, quality score, and liver stiffness of the two sequences. In addition, Spearman's correlation was performed to evaluate the relationship between the R2* value and liver stiffness. RESULTS: The overall success rates of SE MRE and SE-EPI MRE in patients with hepatic iron overload were 91.89% and 78.38%, respectively, and 100% and 78.57%, respectively, for severe elevation iron overload. In all patients, the MRE quality scores were 54 and 48 for SE MRE and SE-EPI MRE, respectively (P = 0.107). There were no significant differences in liver stiffness measurements between the two MRE methods in patients with mild, moderate, and severe elevation iron-overloaded livers (P > 0.6 for all), respectively. For both MRE methods, R2* value had no significant effect on the liver stiffness measurements (correlation coefficient <0.1, P >0.6 for both). CONCLUSION: In the mild and moderate elevation iron-overloaded liver, both SE MRE and fast SE-EPI MRE can provide successful and reliable liver stiffness measurement. In severe elevation iron-overloaded livers, SE MRE may be a better choice than SE-EPI MRE.


Assuntos
Técnicas de Imagem por Elasticidade , Sobrecarga de Ferro , Humanos , Técnicas de Imagem por Elasticidade/métodos , Reprodutibilidade dos Testes , Estudos Retrospectivos , Fígado/diagnóstico por imagem , Fígado/patologia , Cirrose Hepática/patologia , Imageamento por Ressonância Magnética/métodos , Imagem Ecoplanar/métodos , Sobrecarga de Ferro/diagnóstico por imagem , Sobrecarga de Ferro/patologia , Ferro
2.
Cell Mol Biol (Noisy-le-grand) ; 69(8): 96-101, 2023 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-37715414

RESUMO

This study was to investigate the changes in gut microbiota in maintenance hemodialysis patients and analyze their impact on patient's microinflammation status. For this purpose, thirty-nine chronic kidney disease (CKD) maintenance hemodialysis patients admitted to our hospital from March 2019 to March 2022 were selected as the experimental group, and 40 healthy individuals with examination results during the same period were selected as the control group. The levels of gut microbiota (Lactobacillus, Bifidobacterium, Escherichia coli, and Enterococcus faecalis) and microinflammation indicators [interleukin-6 (IL-6), tumor necrosis factor α (TNF-α), and high-sensitivity C-reactive protein (hs-CRP)] were measured in both groups. The relationship between changes in gut microbiota and microinflammation in maintenance hemodialysis CKD patients was analyzed. Results showed that the levels of Lactobacillus and Bifidobacterium in the experimental group were significantly lower than those in the control group (all, P<0.05), while the levels of Escherichia coli and Enterococcus faecalis in the experimental group were significantly higher than those in the control group (all, P<0.05). The IL-6, TNF-α, and hs-CRP levels in the experimental group were significantly higher than those in the control group (all, P<0.05). Using microinflammation indicators as dependent variables and microbiota indicators as independent variables for stepwise regression analysis, the results showed that the levels of Lactobacillus were negatively correlated with IL-6 and TNF-α levels in patients (r=-0.358, -0.942, P<0.05); the levels of Bifidobacterium were negatively correlated with IL-6, TNF-α, and hs-CRP levels in patients (r=-0.394, -0.211, -0.547, P<0.05); the levels of Escherichia coli were positively correlated with IL-6 and TNF-α levels in patients (r=0.221, 0.268, P<0.05); the levels of Enterococcus faecalis were positively correlated with IL-6 and hs-CRP levels in patients (r=0.253, 0.378, P<0.05). In conclusion, patients with maintenance hemodialysis for CKD commonly exhibit gut microbiota dysbiosis and varying degrees of low-grade inflammation. Compared to healthy individuals, maintenance hemodialysis patients with CKD have lower levels of Bifidobacterium and Lactobacillus and higher levels of Escherichia coli and Enterococcus in their gut. Bifidobacterium, Lactobacillus, Escherichia coli, and Enterococcus all have a certain impact on the low-grade inflammation status of patients with maintenance hemodialysis for CKD.


Assuntos
Microbioma Gastrointestinal , Insuficiência Renal Crônica , Humanos , Proteína C-Reativa , Interleucina-6 , Fator de Necrose Tumoral alfa , Enterococcus , Enterococcus faecalis , Escherichia coli , Inflamação , Lactobacillus , Diálise Renal
3.
Int J Gen Med ; 14: 2943-2951, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34234524

RESUMO

OBJECTIVE: This study aimed to examine the magnetic resonance imaging (MRI) characteristics of primary cardiac neoplastic lesions. METHODS: A retrospective investigation was conducted on 24 cases of primary cardiac neoplastic lesions as confirmed by surgery and pathology results. All the cases in this study received MRI multi-sequence and multi-dimension scanning, including the cardiac long-axis and short-axis cine sequences, parameter sequences of the cardiac long axis and short axis (T1WI, T2WI), first-pass perfusion sequence, and delayed enhancement sequence of the cardiac long axis and short axis. The age and gender of the patients and the location, size, signal characteristics, and relationship with the neighboring tissues of all the lesions were examined. RESULTS: Twenty-four cases of primary neoplastic lesions were examined in this study, the onset age was 11-72 years old, the median age was 53 years old, and the mean age was 46 years old. Among these cases, there were 8 cases including males and 16 cases including females, 19 cases were benign lesions; including 11 cases of myxoma, 4 cases of hemangioma, 1 case of paraganglioma, 1 case of PEcoma, 1 case of hamartoma, and 1 case of lipoma. The malignant lesions included 3 sarcomas and 2 lymphomas in 5 patients. CONCLUSION: MRI imaging provides a great value in the preoperative classification of primary cardiac neoplastic lesions.

4.
BMC Med Inform Decis Mak ; 20(1): 239, 2020 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-32957985

RESUMO

BACKGROUND: The present study aims to investigate the role of histogram analysis of intravoxel incoherent motion (IVIM) in the differential diagnosis of benign and malignant breast lesions. METHODS: The magnetic resonance imaging and clinical data of 55 patients (63 lesions) were retrospectively analyzed. The multi-b-valued diffusion-weighted imaging image was processed using the MADC software to obtain the gray-scaled maps of apparent diffusion coefficient (ADC)-slow, ADC-fast and f. The MaZda software was used to extract the histogram metrics of these maps. Combined with the conventional sequence images, the region of interest (ROI) was manually drawn along the edge of the lesion at the maximum level of the gray-scale image, and the difference of the data was analyzed between the benign and malignant breast lesions. RESULTS: There were 29 patients with 37 benign lesions, which included 23 fibroadenomas, 6 adenosis, 1 breast cysts, 4 intraductal papillomas, and 3 inflammations of breast. Furthermore, 26 malignant lesions in 26 patients, which included 20 non-specific invasive ductal carcinomas, 5 intraductal carcinomas and 1 patient with squamous cell carcinoma. The ADC-slow (mean and the 50th percentile) and f (minimum, mean, kurtosis, the 10th percentile and 50th percentile) of these malignant breast lesions were significantly lower than those of benign lesions (P < 0.05), while ADC-fast (kurtosis) and f (variance, skewness) of these malignant breast lesions were significantly higher than those of benign lesions (P < 0.05). CONCLUSION: The histogram analysis of ADC-slow (mean and the 50th percentile), ADC-fast (kurtosis) and f (minimum, mean, kurtosis, the 10th percentile and 50th percentile. Variance, skewness) can provide a more objective and accurate basis for the differential diagnosis of benign and malignant breast lesions.


Assuntos
Neoplasias da Mama , Interpretação de Imagem Assistida por Computador , Neoplasias da Mama/diagnóstico por imagem , Diagnóstico Diferencial , Imagem de Difusão por Ressonância Magnética , Humanos , Estudos Retrospectivos , Sensibilidade e Especificidade
5.
Bioorg Med Chem ; 21(9): 2663-70, 2013 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-23510562

RESUMO

Aminopeptidase N (APN/CD13), as a zinc-containing ectoenzyme, plays a critical role in the process of tumor angiogenesis, invasion and metastasis. Through the docking-based virtual screening of chemical databases and the further activity assay, we discovered that compound 10c exhibits potent and selective inhibitory ability towards APN. In addition, a series of indoline-2,3-dione derivates have been designed and synthesized as APN inhibitors. The results of preliminary activity evaluation showed that compound 12a (IC(50) = 0.074 ± 0.0026 µM) exhibited the best inhibitory activity against APN, which could be used for further anticancer agent research.


Assuntos
Antígenos CD13/antagonistas & inibidores , Indóis/farmacologia , Inibidores de Proteases/farmacologia , Antígenos CD13/metabolismo , Relação Dose-Resposta a Droga , Humanos , Indóis/síntese química , Indóis/química , Modelos Moleculares , Estrutura Molecular , Inibidores de Proteases/síntese química , Inibidores de Proteases/química , Relação Estrutura-Atividade
6.
J Enzyme Inhib Med Chem ; 28(3): 545-51, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22380779

RESUMO

Aminopeptidase N (APN/CD13) over expressed on tumour cells, plays a critical role in tumour invasion, metastasis and tumour angiogenesis. In this article, we described the design, synthesis and preliminary activity studies of novel 3-amino-2-hydroxyl-3-phenylpropanoic acid derivatives as APN inhibitors. The in vitro enzymatic inhibitions on APN from porcine kidney showed that compound 7e had the most potent inhibitory activity against APN with the IC(50) value to 1.26 ± 0.01 µM, which is better than that of bestatin (IC(50) = 2.55 ± 0.11 µM). In addition, compound 7e also showed better inhibitory activity against APN on human ovary clear cell carcinoma cell ES-2 than bestatin with the IC(50) value to 30.19 ± 1.02 µM versus 60.61 ± 0.1 µM. Compound 7e could be used as the lead compound in the future for anti-cancer agent research.


Assuntos
Antineoplásicos/farmacologia , Antígenos CD13/antagonistas & inibidores , Fenilpropionatos/química , Inibidores de Proteases/síntese química , Inibidores de Proteases/farmacologia , Animais , Antineoplásicos/química , Linhagem Celular Tumoral , Técnicas de Química Sintética , Desenho de Fármacos , Feminino , Concentração Inibidora 50 , Rim/enzimologia , Leucina/análogos & derivados , Leucina/farmacologia , Simulação de Acoplamento Molecular , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/patologia , Inibidores de Proteases/química , Relação Estrutura-Atividade
7.
J Enzyme Inhib Med Chem ; 28(4): 717-26, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22545941

RESUMO

Aminopeptidase N (APN/CD13) is one of the essential proteins for tumour invasion, angiogenesis and metastasis as it is over-expressed on the surface of different tumour cells. Based on our previous work that L-isoserine dipeptide derivatives were potent APN inhibitors, we designed and synthesized L-isoserine tripeptide derivatives as APN inhibitors. Among these compounds, one compound 16l (IC50 = 2.51 ± 0.2 µM) showed similar inhibitory effect compared with control compound Bestatin (IC50 = 6.25 ± 0.4 µM) and it could be used as novel lead compound for the APN inhibitors development as anticancer agents in the future.


Assuntos
Antígenos CD13/antagonistas & inibidores , Desenho de Fármacos , Oligopeptídeos/farmacologia , Inibidores de Proteases/síntese química , Inibidores de Proteases/farmacologia , Serina/análogos & derivados , Antineoplásicos/síntese química , Antineoplásicos/química , Antineoplásicos/farmacologia , Antígenos CD13/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Células HL-60 , Humanos , Células K562 , Modelos Moleculares , Conformação Molecular , Oligopeptídeos/síntese química , Oligopeptídeos/química , Inibidores de Proteases/química , Serina/síntese química , Serina/química , Serina/farmacologia , Relação Estrutura-Atividade
8.
Bioorg Med Chem Lett ; 22(18): 5863-9, 2012 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-22901392

RESUMO

A virtual screening was performed to discover novel lead structures as potent aminopeptidase N(APN) inhibitors. A commercial database containing about 1,60,000 molecules in SPECS was filtered by rule of five, zinc binding groups, pharmacophore models and binding pattern analysis. At last, 24 molecules were selected for enzyme inhibition assay and compound 2 exhibited the inhibition constant (K(i)) of 2.79±0.32 µM against APN compared with Bestatin (K(i)= 3.37±0.24 µM). Our results indicated that compound 2 exhibited good antiproliferative activities against a broad spectrum of human cancer cell lines, and induced cell cycle arrest at G1 phase and eventual apoptosis. Moreover, compound 2 can inhibit the invasion of MDA-MB-231 cells. In summary, our results suggest that compound 2, a potent APN inhibitor, is worthy of further development.


Assuntos
Antineoplásicos/farmacologia , Antígenos CD13/antagonistas & inibidores , Inibidores Enzimáticos/farmacologia , Ensaios de Triagem em Larga Escala , Animais , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Antígenos CD13/metabolismo , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Ensaios de Seleção de Medicamentos Antitumorais , Inibidores Enzimáticos/química , Células HL-60 , Humanos , Camundongos , Modelos Moleculares , Estrutura Molecular , Relação Estrutura-Atividade , Células Tumorais Cultivadas
9.
Bioorg Med Chem ; 19(20): 6015-25, 2011 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-21911297

RESUMO

A series of novel 1,2,3,4-tetrahydroisoquinoline-3-carboxylic acid derivatives were designed, synthesized and assayed for their activities against aminopeptidase N (APN/CD13) and MMP-2. The results showed that most compounds exhibited higher inhibitory activities against APN than that of MMP-2. Within this series, compound 12h (IC(50)=6.28 ± 0.11 µM) showed similar inhibitory activities compared with Bestatin (IC(50)=5.55 ± 0.01 µM), and it could be used as novel lead compound for the future APN inhibitors development as anticancer agents.


Assuntos
Antineoplásicos/síntese química , Antígenos CD13/antagonistas & inibidores , Inibidores de Proteases/síntese química , Tetra-Hidroisoquinolinas/síntese química , Tetra-Hidroisoquinolinas/farmacologia , Antineoplásicos/farmacologia , Antígenos CD13/química , Antígenos CD13/metabolismo , Desenho de Fármacos , Humanos , Inibidores de Proteases/farmacologia , Relação Estrutura-Atividade , Tetra-Hidroisoquinolinas/química
10.
Talanta ; 85(1): 743-8, 2011 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-21645768

RESUMO

A simple and low-cost high-throughput dynamic microwave-assisted extraction (HTDMAE) device was firstly assembled and validated by the extraction of nicotine in mushroom samples. In this device, a household microwave oven was applied to provide the microwave energy; a vacuum pump was used to deliver the solvent. Compared with traditional dynamic microwave-assisted extraction method, the sample throughput and microwave energy utilization were improved by the HTDMAE, up to 20 samples could be treated simultaneously in 9 min. Taking extraction of nicotine in mushroom sample as an example, a method was established with extraction, separation and enrichment of nicotine in a single step by the device on-line coupled with solid-phase extraction (SPE). Nicotine was first extracted from the mushroom samples with water under the action of microwave energy, and then directly introduced into the SPE column which was packed with cation-exchange resins. Subsequently, the nicotine trapped on the resins was eluted with methanol-ammonia (95:5, v/v) and determined by high-performance liquid chromatography. The limit of detection of nicotine obtained is 5.6 µg kg(-1) in fresh mushroom sample. The recovery of nicotine in mushroom samples is in the range of 87.4-104.0%. The proposed method which significantly reduced the overall analysis time and increased sample throughput should be favored for routine analyse of complex solid sample.


Assuntos
Agaricales/química , Micro-Ondas , Nicotina/análise , Extração em Fase Sólida/métodos , Resinas de Troca de Cátion , Cromatografia Líquida de Alta Pressão , Ensaios de Triagem em Larga Escala , Limite de Detecção , Nicotina/isolamento & purificação
11.
Anal Bioanal Chem ; 400(2): 517-26, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21347671

RESUMO

In the study, a fast and selective method based on magnetic separation has been developed for the extraction of nicotine from human plasma using magnetic strong cation exchange (MSCX) resins as adsorbent. MSCX resins were prepared using hydrophobic Fe(3)O(4) magnetite as magnetically susceptible component, styrene and acrylic acid as polymeric matrix components, and acetyl sulfonate as the sulfonation agent. The extraction procedure was carried out in a single step by stirring the mixture of diluted plasma sample and MSCX resins in the vortex for 5 min. Then, the resins with adsorbed nicotine were separated from the sample matrix by applying an appropriate magnetic field. Main factors affecting the extraction of nicotine such as the amount of MSCX resins, pH value of the extraction solvent, extraction time, and washing and eluting conditions were optimized. The nicotine eluted from the resins was determined by liquid chromatography-tandem mass spectrometry. The calibration curve obtained by analyzing matrix-matched standards shows excellent linear relationship (r (2) = 0.9998) in the concentration range of 10-2,500 ng mL(-1). The limit of detection and quantification obtained are 2.9 and 9.7 ng mL(-1), respectively. The relative standard deviations of intra- and inter-day obtained are in the range of 1.9-6.9% and 2.5-7.8% with the recoveries ranging from 78.7% to 99.1%. The proposed method was successfully applied to determine nicotine in human plasma phlebotomized from ten male smokers. Nicotine was detectable with the contents ranging from 44.4 to 221.9 ng mL(-1) in five samples.


Assuntos
Resinas de Troca de Cátion/química , Cromatografia Líquida/métodos , Nicotina/sangue , Extração em Fase Sólida/métodos , Espectrometria de Massas em Tandem/métodos , Adsorção , Cromatografia Líquida/instrumentação , Humanos , Magnetismo , Masculino , Nicotina/isolamento & purificação , Fumar/sangue , Extração em Fase Sólida/instrumentação , Espectrometria de Massas por Ionização por Electrospray/métodos
12.
Bioorg Med Chem ; 18(16): 5981-7, 2010 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-20637634

RESUMO

Aminopeptidase N (APN/CD13) over expressed on tumor cells, plays a critical role in tumor invasion, metastasis, and tumor angiogenesis. Here we described the design, synthesis and preliminary activity studies of novel APN inhibitors with 3-phenylalanyl-N'-substituted-2,6-piperidinedione scaffold. The results showed that compound 7c had the most potent inhibitory activity against APN with the IC(50) value to 5.00 +/-3.17 microM, which could be used as the lead compound in the future for anticancer agent research.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Antígenos CD13/antagonistas & inibidores , Piperidonas/química , Piperidonas/farmacologia , Inibidores de Proteases/química , Inibidores de Proteases/farmacologia , Animais , Antineoplásicos/síntese química , Antígenos CD13/metabolismo , Proliferação de Células/efeitos dos fármacos , Células HL-60 , Humanos , Concentração Inibidora 50 , Estrutura Molecular , Neoplasias/tratamento farmacológico , Fenilalanina/síntese química , Fenilalanina/química , Piperidonas/síntese química , Inibidores de Proteases/síntese química , Relação Estrutura-Atividade , Suínos
13.
Bioorg Med Chem ; 18(5): 1761-72, 2010 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-20171895

RESUMO

Histone deacetylases (HDACs) are enzymes involved in tumor genesis and development. Herein, we report a novel series of 1,2,3,4-tetrahydroisoquinoline-3-carboxylic acid derivatives as HDACs inhibitors. The preliminary biological screening showed that most of our compounds exhibited potent inhibitory activity against HDACs. Within this series, five compounds, 13a (IC(50)=0.58+/-0.10 microM), 7d (IC(50)=1.00+/-0.16 microM), 8l (IC(50)=1.06+/-0.14 microM), 7i (IC(50)=1.17+/-0.19 microM) and 7a (IC(50)=1.29+/-0.15 microM) possessed better HDACs inhibitory activity than Vorinostat (IC(50)=1.48+/-0.20 microM). So these five compounds could be used as novel lead compounds for further design of HDACs inhibitors. The anti-proliferative activities of a few compounds and the structure-activity relationships are also briefly discussed.


Assuntos
Antineoplásicos/síntese química , Inibidores de Histona Desacetilases/síntese química , Histona Desacetilases/química , Ácidos Hidroxâmicos/síntese química , Isoquinolinas/síntese química , Tetra-Hidroisoquinolinas/química , Antineoplásicos/química , Antineoplásicos/farmacologia , Sítios de Ligação , Domínio Catalítico , Linhagem Celular Tumoral , Simulação por Computador , Desenho de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Células HL-60 , Inibidores de Histona Desacetilases/química , Inibidores de Histona Desacetilases/farmacologia , Histona Desacetilases/metabolismo , Humanos , Ácidos Hidroxâmicos/química , Ácidos Hidroxâmicos/farmacologia , Isoquinolinas/química , Isoquinolinas/farmacologia , Relação Estrutura-Atividade , Tetra-Hidroisoquinolinas/síntese química , Tetra-Hidroisoquinolinas/farmacologia
14.
Curr Med Chem ; 15(27): 2850-65, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18991640

RESUMO

APN is an important zinc dependent metallo-exopeptidase; it has been considered as a suitable target for anti-cancer drug design. In this review we focus on the most effective and the most promising inhibitors of aminopeptidase N. Their binding modes to the enzyme, the attempt to explain the origin of the inhibitory activity, as well as the structure-activity relationship for some of these compounds are discussed. Besides, the structural and electronic requirements of the enzyme active site and the binding pockets, together with the specificity towards the ligands are presented.


Assuntos
Antineoplásicos/farmacologia , Antígenos CD13/antagonistas & inibidores , Inibidores de Proteases/farmacologia , Antineoplásicos/química , Sítios de Ligação , Antígenos CD13/química , Antígenos CD13/metabolismo , Humanos , Modelos Químicos , Modelos Moleculares , Estrutura Molecular , Inibidores de Proteases/química
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