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1.
J Colloid Interface Sci ; 658: 540-552, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38128197

RESUMO

Design of engineered cells to target and deliver nanodrugs to the hard-to-reach regions has become an exciting research area. However, the limited penetration and retention of cell-based carriers in tumor tissue restricted their therapeutic efficiency. Inspired by the enhanced delivery behavior of mobile micro/nanomotors, herein, urease-powered platelet cell motors (PLT@Au@Urease) capable of active locomotion, tumor targeting, and radiosensitizers delivery were designed for boosting radiosensitization. The engineered platelet cell motors were constructed by in situ synthesis and loading of radiosensitizers gold nanoparticles in platelets, and then conjugation with urease as the engine. Under physiological concentration of urea, thrust around PLT@Au@Urease motors can be generated via the biocatalytic reactions of urease, leading to rapid tumor cell targeting and enhanced cellular uptake of radiosensitizers. Encouragingly, in comparison with engineered PLT without propulsion capability (PLT@Au), the self-propelled PLT@Au@Urease motors could significantly increase intracellular ROS level and exacerbate nuclear DNA damage induced by γ-radiation, resulting in a remarkably high sensitization enhancement rate (1.89) than that of PLT@Au (1.08). In vivo experiments with 4 T1-bearing mice demonstrated that PLT@Au@Urease in combination with radiation therapy possessed good antitumor performance. Such an intelligent cell motor would provide a promising approach to enhance radiosensitization and broaden the applications of cell motor-based delivery systems.


Assuntos
Nanopartículas Metálicas , Neoplasias , Animais , Camundongos , Ouro/farmacologia , Urease , Neoplasias/radioterapia
2.
Sensors (Basel) ; 23(5)2023 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-36904776

RESUMO

Image-text retrieval aims to search related results of one modality by querying another modality. As a fundamental and key problem in cross-modal retrieval, image-text retrieval is still a challenging problem owing to the complementary and imbalanced relationship between different modalities (i.e., Image and Text) and different granularities (i.e., Global-level and Local-level). However, existing works have not fully considered how to effectively mine and fuse the complementarities between images and texts at different granularities. Therefore, in this paper, we propose a hierarchical adaptive alignment network, whose contributions are as follows: (1) We propose a multi-level alignment network, which simultaneously mines global-level and local-level data, thereby enhancing the semantic association between images and texts. (2) We propose an adaptive weighted loss to flexibly optimize the image-text similarity with two stages in a unified framework. (3) We conduct extensive experiments on three public benchmark datasets (Corel 5K, Pascal Sentence, and Wiki) and compare them with eleven state-of-the-art methods. The experimental results thoroughly verify the effectiveness of our proposed method.

3.
Open Med (Wars) ; 17(1): 1705-1711, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36382056

RESUMO

This study aimed to evaluate the effects of delayed femoral vein ligation on the clinical outcomes of hip disarticulation. We retrospectively reviewed 20 patients with extremity tumors (10 bone tumors and 10 soft tissue sarcomas [STS]) who underwent hip disarticulation. Patients treated for hip disarticulation with synchronous femoral vein ligation (n = 10, regular surgery group) and hip disarticulation with delayed femoral vein ligation (n = 10, delayed ligation group), respectively, were enrolled in this study. The operative time and blood loss were used to evaluate the clinical outcomes. The delayed ligation group had significantly lower operative times than the regular surgery group (P < 0.05). Total, hidden, and intraoperative blood loss were all significantly lower in the delayed ligation group than in the regular surgery group (P < 0.05). However, there were no significant differences in postoperative blood loss. In conclusion, delayed femoral vein ligation could significantly reduce the operative time, hidden blood loss, and intraoperative blood loss in patients undergoing hip disarticulation.

4.
Oncol Lett ; 14(5): 5890-5898, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29113223

RESUMO

Cancer stem cells are enriched in triple-negative breast cancer (TNBC) tumor tissues, which present strong capacities of proliferation and tumorigenicity. The present study detected the distribution of cancer stem cell markers cluster of differentiation (CD)44/CD24 and analyzed the clinical outcomes of different CD44/CD24 phenotypes in patients with TNBC. Multivariate Cox regression analyses were performed with regard to the prognostic value of cancer stem cell markers CD44/CD24, aldehyde dehydrogenase 1 and other baseline clinical characteristics, including tumor size, lymph node involved, adjuvant chemotherapy, Ki-67, breast cancer susceptibility gene 1, cellular tumor antigen p53, vimentin and basal-like status. The multivariate analyses showed that three of these factors, CD44/CD24 phenotype, basal-like status and number of lymph nodes involved, had an impact on overall survival. Furthermore, patients with CD44+/CD24- phenotype, basal-like tumors and ≥4 lymph nodes involved had a significantly worse prognosis. The expression of CD44 and CD24 was detected by double-staining immunohistochemistry, which can locate cancer stem cells individually. Overall, the present results indicated that CD44/CD24 status evaluated by double-staining immunohistochemistry constitutes an independent prognostic factor for TNBC.

5.
Mol Carcinog ; 56(3): 1055-1067, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27648737

RESUMO

Cancer is one of the leading causes of death worldwide, and oral squamous cell carcinoma (OSCC) accounts for almost a sixth of all reported cancers. Arecoline, from areca nut is known to enhance carcinogenesis in oral squamous cells. The objective of this study is to determine the effect of Taiwanin C, from Taiwania cryptomerioides Hayata against Arecoline-associated carcinogenesis. An OSCC model was created in C57BL/6J Narl mice by administrating 0.5 mg mL-1 arecoline with 0.2 mg mL-1 4-NQO carcinogen for 8 and 28 wk to mimic the etiology of oral cancer patients in Asia. Mice were sacrificed and two cell lines, T28 from the tumor and N28 cancerous cell line from the surrounding non tumor area, were established. Taiwanin C showed effective anti-tumor activity in nude mice models. Taiwanin C significantly inhibited the cell viability of T28 cells in a dose dependent manner, but did not inflict any effect on N28 normal cells. Taiwanin C treatment inhibited the migration ability of T28 cells in a dose dependent manner as determined by wound healing and migration assays. Taiwanin C also reduced the levels of ß-catenin and its downstream metastatic proteins, Tbx3 and c-Myc. Besides, Taiwanin C inhibited the nuclear accumulation of ß-catenin and induced ß-catenin degradation via proteasome-mediated pathway. Moreover, Taiwanin C enhanced GSK-3ß and reduced the p-ser9 GSK-3ß protein level to inactivate Wnt signaling. Taken together, Taiwanin C blocked the cell migration effects of T28 cells mediated through the activation of GSK-3ß to enhance protein degradation and reduce nuclear accumulation of ß-catenin. © 2016 Wiley Periodicals, Inc.


Assuntos
Regulação para Baixo , Glicogênio Sintase Quinase 3 beta/metabolismo , Lactonas/administração & dosagem , Lignanas/administração & dosagem , Neoplasias Bucais/tratamento farmacológico , beta Catenina/metabolismo , 4-Nitroquinolina-1-Óxido/efeitos adversos , Animais , Arecolina/efeitos adversos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ativação Enzimática , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Lactonas/farmacologia , Lignanas/farmacologia , Camundongos , Neoplasias Bucais/induzido quimicamente , Neoplasias Bucais/metabolismo , Transdução de Sinais/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
6.
Cancer Sci ; 107(7): 882-9, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27145494

RESUMO

The aim of this study was to establish a prognostic risk model for patients with triple negative breast cancer (TNBC). A total of 278 specimens of human TNBC tissues were investigated by immunohistochemistry for growth-arrest specific protein 6 expression, infiltrations of stromal natural killer cells and tumor-associated macrophages. According to their prognostic risk scores based on the model, patients were divided into three groups (score 0, 1-2, 3). Correlations of prognostic risk scores, clinicopathologic features and overall survival (OS) were analyzed. To study the clinical value of this stratification model in early disease recurrence or metastasis, 177 patients were screened out for further analysis. Based on disease free survival (DFS), 90 patients fell within the DFS ≤3 years group and 87 patients within the DFS ≥5 years group. We analyzed the differences in prognostic risk scores between the two groups. The prognostic risk scores were negatively related to tumor size, lymph node metastasis and P53 status (P < 0.001 for all). Patients with low prognostic risk scores had longer OS (P = 0.001). Using multivariate analysis, it was determined that TNM stage (HR = 0.432, 95% confidence interval [CI] = 0.281-0.665, P = 0.003), FOXP3 positive lymphocytes (HR = 1.712, 95% CI = 1.085-2.702, P = 0.021) and prognostic risk scores (HR = 1.340, 95% CI = 1.192-1.644, P = 0.005) were independent prognostic factors for OS. Compared with the DFS ≥5 years group, the DFS ≤3 years group patients had significantly higher prognostic risk scores (P < 0.001). In conclusion, the prognostic risk score of the model was a significant indicator of prognosis for patients with TNBC.


Assuntos
Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Células Matadoras Naturais/imunologia , Macrófagos/imunologia , Células Estromais/imunologia , Neoplasias de Mama Triplo Negativas/diagnóstico , Neoplasias de Mama Triplo Negativas/imunologia , Evasão Tumoral/imunologia , Adulto , Idoso , Feminino , Humanos , Tolerância Imunológica , Células Matadoras Naturais/patologia , Macrófagos/patologia , Pessoa de Meia-Idade , Prognóstico , Medição de Risco , Neoplasias de Mama Triplo Negativas/metabolismo , Neoplasias de Mama Triplo Negativas/patologia , Microambiente Tumoral
7.
Int J Oncol ; 48(3): 1063-72, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26794366

RESUMO

It is believed that breast cancer stem cells (BCSCs), like normal stem cell counterparts, have the capacity of self-renewal and differentiation. Simultaneously, estrogen receptor (ER)-negative (-) BCSCs are affected by surrounding differentiated ER-positive (+) tumor cells by virtue of paracrine signaling within the tumor micro-environment. Genistein (GEN), as a sort of phytoestrogen, can act on ER+ breast cancer cells but the role of GEN in the differentiation of neighboring ER- BCSCs has not been defined. Transwell co-culture system was utilized so as to elaborate the interaction between well-differentiated ER+ breast cancer cells (MCF-7) and ER- breast cancer stem/progenitor cells (mammospheres derived from MDA-MB-231 cells). GEN-induced differentiation of BCSCs was analyzed by mammospheres formation assay, flow cytometry and RT-PCR after a 3 day solo-culture or co-culture. We find that GEN sized 2 µM, and 40 nM, effectively promotes morphological alteration of mammospheres, reduces the ratio of subset of CD44+/CD24-/ESA+ cells and upregulates the expression of differentiated cell markers of mammospheres in co-culture system, but not in solo-culture condition. Besides, we demonstrate that the differentiation-inducing effect of GEN on mammospheres is associated with PI3K/Akt and MEK/ERK signaling pathways which are activated by amphiregulin released from ER+ cancer cells. These results indicate that GEN was able to induce the differentiation of breast cancer stem/progenitor cells through interaction with ER+ cancer cells by a paracrine mechanism.


Assuntos
Antineoplásicos/química , Neoplasias da Mama/patologia , Genisteína/química , Células-Tronco Neoplásicas/citologia , Células-Tronco/citologia , Neoplasias da Mama/metabolismo , Diferenciação Celular , Linhagem Celular Tumoral , Proliferação de Células , Técnicas de Cocultura , Meios de Cultivo Condicionados/química , Estradiol/química , Receptor alfa de Estrogênio/metabolismo , Feminino , Citometria de Fluxo , Humanos , Células MCF-7 , Comunicação Parácrina , Fitoestrógenos/química , Transdução de Sinais , Microambiente Tumoral
8.
Dig Dis Sci ; 57(12): 3184-8, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22722879

RESUMO

BACKGROUND AND AIMS: The nuclear factor of the activated T cell (NFAT) family was primarily recognized for its central role in T lymphocyte activation. Recent evidence showed that NFAT isoforms participate in the regulation of genes related to cell proliferation and differentiation in epithelial malignancies. Here, we investigated the expression and activation of the calcineurin/NFAT transcription pathway and its role in hepatocellular carcinoma (HCC) proliferation. METHODS: Expression of NFATc1 and calcineurin proteins was examined by immunohistochemical analyses in 76 human HCC samples. The cellular NFAT activation and distribution in HepG2 cells were analyzed by immunofluorescence and western blot analyses. After NFATc1 expression was knocked down by NFATc1-specific siRNA, we analyzed its implications in cell cycle progression and growth by MTT and flow cytometry. The impact of calcineurin/NFAT signaling on protein expression of c-myc and cox-2 were performed by western blot analyses. RESULTS: NFATc1 is significantly overexpressed in HCC. The regulation of calcineurin activity by ionomycin or cyclosporin A caused rapid nuclear import or export of NFATc1 in HepG2 cells. NFATc1 knock-down led to a significant reduction in proliferation rates and cell cycle arrest at G1 phase. The expression of c-myc and cox-2 was decreased in the NFATc1 knock-down HepG2 cells. Ionomycin increased c-myc and cox-2 expression in HepG2 cells, but not in siNFATc1 HepG2 cells. CONCLUSION: The calcineurin/NFATc1 signal is overexpressed and active in HCC. It may enhance the proliferative potential of HepG2 cells through transcriptional activation of the c-myc and cox-2 oncogenes.


Assuntos
Calcineurina/metabolismo , Carcinoma Hepatocelular/metabolismo , Regulação Neoplásica da Expressão Gênica/fisiologia , Neoplasias Hepáticas/metabolismo , Fatores de Transcrição NFATC/metabolismo , Transporte Ativo do Núcleo Celular/fisiologia , Calcineurina/genética , Cálcio/metabolismo , Ciclo Celular , Linhagem Celular , Proliferação de Células , Humanos , Fatores de Transcrição NFATC/genética , Oncogenes , Transdução de Sinais
9.
J AOAC Int ; 94(3): 839-46, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21797012

RESUMO

An HPLC/MS/MS method was developed for the simultaneous determination of the following benzimidazole anthelmintics and metabolites in plasma: flubendazole, albendazole, fenbendazole, mebendazole, thiabendazole, hydrolyzed flubendazole, albendazole sulfoxide, albendazole sulfone, albendazole aminosulfone, oxfendazole, fenbendazole sulfone, aminomebendazole, hydroxymebendazole, and 5-hydroxythiabendazole. The sample preparation process involved a pH-dependent extraction of the analytes. Chromatographic separation was performed on a C18 column with a mobile phase gradient starting with methanol-water (20 + 80, v/v) containing 0.1% formic acid. The overall average recoveries of the analytes based on a matrix-matched calibration ranged from 75.0 to 120.0%, with RSD values of <20.0%. The LODs ranged from 0.08 to 2.0 microg/kg and the LOQs from 0.3 to 5.0 microg/kg. The validated method was used in pharmacokinetic studies of benzimidazole compounds in rabbits, and the elimination of the metabolites was measured quantitatively.


Assuntos
Benzimidazóis/sangue , Benzimidazóis/química , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas em Tandem/métodos , Animais , Anti-Helmínticos/sangue , Anti-Helmínticos/química , Anti-Helmínticos/metabolismo , Anti-Helmínticos/farmacocinética , Benzimidazóis/metabolismo , Benzimidazóis/farmacocinética , Projetos Piloto , Coelhos , Reprodutibilidade dos Testes
10.
Rapid Commun Mass Spectrom ; 25(7): 889-98, 2011 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-21416525

RESUMO

Olaquindox (OLA), N-(2-hydroxyethyl)-3-methyl-2-quinoxalincarboxamide-1,4-dioxide, is an antimicrobial and growth-promoting agent for animals, which has been banned or allowed only limited use for its potential toxicity. To thoroughly understand the metabolic pathways, metabolism of OLA in rat was studied using ultra-performance liquid chromatography coupled to quadrupole time-of-flight mass spectrometry with MS(E) and mass defect filtering techniques. Twenty metabolites (M1-M20) were detected in rat feces and urine, of which nine phase I metabolites (M6, M7, M11-M16) and four phase II metabolites (M17-M20) were found in vivo for the first time. The structures of metabolites were reliably characterized on the basis of accurate mass and fragment ions in MS(E) spectra. The major metabolic pathways reported previously in pigs, including reduction of N→O groups, oxidation of the alcohol and hydrolysis, were also confirmed in this study. In addition, hydroxylation of the methyl group, N-dehydroxyethylation and glucuronidation were also proved to be the important metabolic pathways, which contribute to improving our knowledge about in vivo metabolism of OLA.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas/métodos , Quinoxalinas/análise , Animais , Fezes/química , Masculino , Quinoxalinas/metabolismo , Quinoxalinas/urina , Ratos , Ratos Sprague-Dawley
11.
CMAJ ; 182(17): 1857-62, 2010 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-20956506

RESUMO

BACKGROUND: The intake of soy isoflavones among women with breast cancer has become a public health concern, because these compounds have weak estrogenic effects. There is little clinical evidence about their safety for patients with breast cancer who are receiving adjuvant endocrine therapy. METHODS: For patients who underwent surgery for breast cancer between August 2002 and July 2003 and who were receiving adjuvant endocrine therapy, we examined associations between dietary intake of soy isoflavones and recurrence of breast cancer and death. We measured dietary intake of soy isoflavones at baseline using a validated food frequency questionnaire. We estimated hazard ratios (HRs) and 95% confidence intervals (CIs) by means of multivariable Cox proportional hazards regression models. We further stratified the analyses by hormonal receptor status and endocrine therapy. RESULTS: The median follow-up period for the 524 patients in this study was 5.1 years. Among premenopausal patients, the overall death rate (30.6%) was not related to intake of soy isoflavones (HR = 1.05, 95% CI 0.78-1.71 for the highest quartile [> 42.3 mg/day] v. the lowest quartile [< 15.2 mg/day], p for trend = 0.87). Relative to post-menopausal patients in the lowest quartile of soy isoflavone intake, the risk of recurrence for post-menopausal patients in the highest quartile was significantly lower (HR = 0.67, 95% CI 0.54-0.85, p for trend = 0.02). Inverse associations were observed in patients with estrogen and progesterone receptor positive disease and those receiving anastrozole therapy. INTERPRETATION: High dietary intake of soy isoflavones was associated with lower risk of recurrence among post-menopausal patients with breast cancer positive for estrogen and progesterone receptor and those who were receiving anastrozole as endocrine therapy.


Assuntos
Antineoplásicos Hormonais/uso terapêutico , Neoplasias da Mama/induzido quimicamente , Isoflavonas/efeitos adversos , Alimentos de Soja/efeitos adversos , Adulto , Idoso , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/mortalidade , Quimioterapia Adjuvante , Intervalos de Confiança , Dieta/efeitos adversos , Inquéritos sobre Dietas , Feminino , Humanos , Menopausa , Pessoa de Meia-Idade , Análise Multivariada , Modelos de Riscos Proporcionais , Recidiva , Leite de Soja
12.
Se Pu ; 28(1): 38-42, 2010 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-20458918

RESUMO

An ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/ MS) method was established for the determination of methaqualone, chloropromazine, promethazine, diazepam, nitrazepam, oxazepam, temazepam, midazolam, triazolam and zolpidem residues in pork and kidney. After enzymolysis, the samples were extracted by ethyl acetate and tert-butyl methyl ether, separately. The separation of the ten sedatives was performed on a Waters Acquity UPLC system with a BEH C18 column. The mobile phases were acetonitrile (containing 0.1% formic acid) and water (containing 0.1% formic acid) at a flow rate of 0.3 mL/min. The electrospray was operated in the positive ionization mode and the ten sedatives were identified by multiple reaction monitoring (MRM) mode. The method of matrix-matched standard solution was adopted as the quantitative method. The calibration curves showed good linearity within the concentrations of 2 - 100 microg/L with the correlation coefficients r > 0. 998. The limits of detection of the ten sedatives were 0.5 microg/kg, and the limit of quantification was 1 microg/kg. The recoveries of the ten sedatives were 64.5% - 111.4% at the spiked levels of 2, 5 and 10 microg/kg. The relative standard deviations of intra- and inter-day coefficients of variation were both less than 15%. This method is simple, sensitive and accurate in the determination of sedative residues.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Resíduos de Drogas/análise , Hipnóticos e Sedativos/análise , Carne/análise , Espectrometria de Massas em Tandem/métodos , Animais , Contaminação de Alimentos/análise , Rim/química , Suínos
13.
Se Pu ; 27(4): 401-5, 2009 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-19938492

RESUMO

A gas chromatography-mass spectrometric (GC-MS) method has been established for the determination of cyromazine and its metabolite melamine in chickens. The homogenized tissue samples added with melamine-15N3 were extracted with acidic acetonitrile-water solution, and defatted with dichloromethane. The samples were derivatized with N,O-bis(trimethylsilyl) trifluoroacetamide (BSTFA), after solid-phase extraction (SPE) which was performed on Oasis MCX cartridges, and then detected by GC-MS. Cyromazine was quantified by an external standard method, and melamine by an internal standard method using melamine-15N3. The results indicated that the linearities of cyromazine and melamine were within the range of 100 - 1,000 microg/L, and their limits of quantification (LOQ) were 20 microg/kg. The mean recoveries of chicken samples fortified at three concentrations of 20, 40 and 80 microg/kg were within the range of 75% - 110%. The relative standard deviations (RSDs) of intra- and inter- batch were less than 10% and 15%, respectively. The application of this method was further demonstrated by analyzing 10 real samples which were brought from local markets. The results show that this method is simple, rapid, sensitive and specific. It is appropriate for the identification and quantification of cyromazine and its metabolite melamine in chickens.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Carne/análise , Resíduos de Praguicidas/análise , Triazinas/análise , Animais , Galinhas , Contaminação de Alimentos/análise
14.
J Agric Food Chem ; 57(23): 11075-80, 2009 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-19899757

RESUMO

A gas chromatography-mass spectrometric (GC-MS) method was established for the determination of cyromazine and its metabolite, melamine, in animal-derived food. Chicken and tilapia muscle samples were spiked with (15)N(3)-melamine, extracted with an acidic acetonitrile/water solution, and defatted with dichloromethane. Egg and milk samples were directly extracted with 3% trichloroacetic acid. The extracts were purified using mixed cation-exchange cartridges, derived with N,O-bis(trimethylsilyl)trifluoroacetamide, and detected by GC-MS. Cyromazine and melamine were quantified by external standard methods except for the determination of melamine in animal muscle, which used an internal standard method. Recoveries ranged from 75.0 to 110.0%, and relative standard deviations were <15.0%. In animal muscle the limits of quantification (LOQs) were 20 microg/kg and the limits of detection (LODs) were 10 microg/kg for cyromazine and melamine. In milk and eggs the LOQs were 10 microg/kg and the LODs were 5 microg/kg for both analytes.


Assuntos
Contaminação de Alimentos/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Resíduos de Praguicidas/análise , Triazinas/análise , Animais , Bovinos , Galinhas , Ovos/análise , Limite de Detecção , Carne/análise , Leite/química , Resíduos de Praguicidas/metabolismo , Tilápia , Triazinas/metabolismo
15.
Int J Colorectal Dis ; 23(7): 675-82, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18340452

RESUMO

BACKGROUND AND AIMS: Early detection and treatment of human colorectal cancers remain a challenge. Identification of new potential markers may help in the diagnosis of colorectal cancer. MATERIALS AND METHODS: By comparative two-dimensional gel electrophoresis using extracts from colorectal tumor and adjacent normal tissues, we identified a calcium-binding protein, S100A11, which was highly expressed in colorectal cancer compared with adjacent normal tissues. We expanded our study in 89 clinical colorectal tumor samples to validate this finding and correlates S100A11 expression in human colorectal cancer tissues with various stages of the tumor by Western blotting and immunohistochemical staining. RESULTS: We identified a calcium-binding protein, S100A11, which was highly expressed in colorectal cancer compared with adjacent normal tissues. S100A protein was expressed predominantly in the cytoplasm of normal tissue; however, it was expressed in both the nuclei and cytoplasm of colorectal cancer. S100A11 level in colorectal cancer tissue was increased following stage progression of the disease. CONCLUSION: These findings suggest S100A11 could be helpful in the pathological study of colorectal cancer, especially for the classification of different stages in colorectal cancer.


Assuntos
Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Proteínas S100/metabolismo , Regulação para Cima , Adulto , Idoso , Linhagem Celular Tumoral , Progressão da Doença , Eletroforese em Gel Bidimensional , Feminino , Imunofluorescência , Humanos , Masculino , Espectrometria de Massas , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Transporte Proteico , Proteínas S100/análise , Proteínas S100/química , Frações Subcelulares/metabolismo
16.
Se Pu ; 26(6): 709-13, 2008 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-19253549

RESUMO

An ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/ MS) method was established for the simultaneous determination of terbutaline, cimaterol, salbutamol, fenoterol, clorprenaline, ractopamine, clenbuterol, tulobuterol, penbutolol residues in animal derived foods. After enzymolysis, the samples were extracted by perchloric acid, centrifuged, neutralized, followed by liquid-liquid extraction with ethyl acetate and tert-butyl methyl ether, separately. The combined extracts were applied to a solid phase extraction MCX cartridge for cleanup. The separation of beta-agonists was performed on Waters Acquity UPLC system with a BEH C18 column (50 mm x 2.1 mm, 1.7 microm) and the gradient elution solvent of acetonitrile (containing 0.1% formic acid) and water (containing 0.1% formic acid) at a flow rate of 0.3 mL/min. The method was quantified by external standard method. The calibration curves were good linear between the peak areas and the concentrations of 0.25 - 5 microg/kg with the correlation coefficient r > 0.990. The limit of detection of the 8 beta-agonists was 0.1 microg/kg, and the limit of quantification was 0.25 microg/kg. The limit of detection of penbutolol was 0.25 microg/kg, and the limit of quantification was 0.5 microg/kg. The average recoveries from spiked animal tissues at three concentrations of 0.5, 1 and 2 microg/kg ranged 87.1% - 108.6%. The relative standard deviations of intra- and inter-batch were both less than 20%.


Assuntos
Agonistas Adrenérgicos beta/análise , Cromatografia Líquida de Alta Pressão/métodos , Análise de Alimentos/métodos , Contaminação de Alimentos/análise , Espectrometria de Massas em Tandem/métodos , Agonistas Adrenérgicos beta/isolamento & purificação , Animais , Calibragem , Bovinos , Limite de Detecção , Modelos Lineares , Carne/análise , Leite/química , Extração em Fase Sólida , Fatores de Tempo
17.
Se Pu ; 24(2): 171-3, 2006 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-16830468

RESUMO

A sensitive and selective method is presented for simultaneous determination of tetracycline antibiotics (TCs) veterinary drugs. Oxytetracycline (OTC), tetracyclines (TC) and chlortetracycline (CTC) in the chicken muscle were extracted, and then solid-phase cleaned-up on a C18 reversed-phase column to obtain an extract suitable for analysis by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Electrospray ionization was applied and operated in the positive ion mode. The calibration curves were good linear between the peak areas and the mass concentrations of TCs from 25 to 500 microg/L with the correlation coefficient more than 0.99. The average recoveries from spiked chicken muscle at the three concentrations of 50, 100 and 200 microg/kg were from 72.4% to 94.9% with relative, standard deviation less than 11%. The detection limits of TCs were 10 microg/kg. The method was successfully validated for chicken muscle in compliance with the requirements set by Document No. 1 of 2003 dispatched by the Bureau of Animal Husbandary of Ministry of Agriculture. This method is suitable for the determination of OTC, TC and CTC in chicken muscle.


Assuntos
Antibacterianos/farmacocinética , Cromatografia Líquida/métodos , Resíduos de Drogas/farmacocinética , Espectrometria de Massas/métodos , Músculos/metabolismo , Tetraciclinas/farmacocinética , Animais , Antibacterianos/análise , Galinhas , Resíduos de Drogas/análise , Limite de Detecção , Carne/análise , Músculos/química , Tetraciclinas/análise , Distribuição Tecidual , Drogas Veterinárias/análise
18.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 19(3): 187-91, 2005 Mar 15.
Artigo em Chinês | MEDLINE | ID: mdl-15828471

RESUMO

OBJECTIVE: To study the effect of combined use of autologous micro-morselized bone with bone morphogenetic protein(BMP) and type I collagen graft on the treatment of segmental bone defects. METHODS: The bulk bone of rabbit iliac crest was ground into micro-morselized bone, which was combined with BMP and type I collagen. The model of 1.5 cm bone defect was established in the middle shaft of the radius. Fifty-six rabbits were assigned to four repairing methods: autologous micro-morselized bone graft with BMP and type I collagen, autologous micro-morselized bone graft with type I collagen, autologous micro-morselized bone graft alone, and control group. The defect-repairing capability of each group was assessed by radiographic, histological, bone densitometry and biomechanical studies. RESULTS: X-ray manifested that at the end of 8 weeks after operation, the bone defect treated with autologous micro-morselized bone graft with BMP and type I collagen was repaired completely, and at the end of 12 weeks after operation the bone defect treated with autologous micro-morselized bone and type I collagen was cured completely, but the bone defect treated with autologous micro-morselized alone was completely repaired. No healing was found in the control group. In the bone densitometry detection, the material with BMP exhibited the strongest defect-repairing capability in terms of amount increased and quality of the new bone at the end of 8 weeks and 12 weeks. The group with BMP has the best mechanical strength of all groups at the end of 12 weeks. CONCLUSION: Autologous micro-morselized bone graft with BMP/type I collagen and autologous micro-morselized bone graft with type I collagen prove to be effective in repairing segmental bone defects. The autologous micro-morselized bone combined BMP and type I collagen is an excellent bone repairing material considering the satisfactory osteogenesis, osteo-conduction, and osteo-induction seen in this method.


Assuntos
Proteínas Morfogenéticas Ósseas/farmacologia , Substitutos Ósseos , Transplante Ósseo/métodos , Colágeno Tipo I/química , Rádio (Anatomia)/cirurgia , Animais , Proteínas Morfogenéticas Ósseas/química , Regeneração Óssea/efeitos dos fármacos , Bovinos , Feminino , Masculino , Coelhos , Rádio (Anatomia)/lesões , Rádio (Anatomia)/fisiopatologia , Distribuição Aleatória , Transplante Autólogo
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