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1.
Food Chem ; 304: 125425, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31476549

RESUMO

Ceramide 2-aminoethylphosphonate (CAEP) is a type of phosphonosphingolipids with potential trophic activity. In this work, complicated CAEP species from different aquatic products were comprehensively identified and semi-quantified by utilizing normal phase liquid chromatography/Q-Exactive mass spectrometry (NPLC/Q-Exactive-MS). We elucidated the fragment schemes of CAEP molecules and found the presence of methylated CAEP (Me-CAEP) species. Remarkably, quantitative results revealed that Loligo chinensis had the highest CAEP content of 4.9 ±â€¯0.4 mg/g dry weight and the most complex molecular species composition, whereas Asterias amurenis had the lowest CAEP content of 1.9 ±â€¯0.6 mg/g dry weight. The most common molecule was CAEP (d19:3-16:0). Additionally, statistical analysis revealed that five aquatic products can be effectively distinguished from their CAEP species; thus, CAEP molecules can play an important role in identifying processed products from aquatic products.

2.
Lipids ; 52(12): 1059-1060, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29134469

RESUMO

Erratum to: Lipids https://doi.org/10.1007/s11745-017-4305-7.

3.
Lipids ; 52(12): 1045-1058, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28975480

RESUMO

A fast and efficient shotgun lipidomics strategy was applied to analyze phospholipids (PL) in the oyster Crassostrea plicatula, including 29 species of phosphatidylcholine (PtdCho), 23 species of phosphatidylethanolamine (PtdEtn), 11 species of phosphatidylserine (PtdSer), 6 species of phosphatidylinositol (PtdIns), and 17 species of lysophospholipids (Lyso-PL). During storage at 4 °C for 7 days, the PL content decreased by 68.08%, but a significant increase in the FFA content was observed (from 63.11 to 318.72 µg/g). PtdCho and PtdIns decreased relatively by 64.97 and 67.49%, and PtdSer decreased most markedly by 74.15%. However, the PtdEtn content increased slightly during the early stages of storage but subsequently began to decrease. Moreover, PL with eicosapentaenoic acid (EPA-PL) and docosahexaenoic acid (DHA-PL) decreased by 51.77 and 50.61%, whereas plasmalogens were relatively stable showing only a 25.46% decrease. In particular, through enzyme activity analysis of lipase, phospholipase A1 (PLA1), phospholipase A2 (PLA2), phospholipase C (PLC), and phospholipase D (PLD), it was observed that the activities of all these enzymes increased at the early stage at 4 °C, but their activities were at lower levels when the oysters were stored at -20 °C. During the storage period at 4 °C, correlation analysis suggests that the degradation of PtdCho was mostly correlated to PLA2 (p < 0.05), whereas PtdEtn and PtdSer were more markedly correlated to lipase and PLD, respectively. The above result indicates that the hydrolysis mechanism of PL during seafood storage was correlated to the lipid hydrolytic enzyme activities under different storage temperatures.


Assuntos
Crassostrea/fisiologia , Fosfolipídeos/análise , Animais , Crassostrea/metabolismo , Hidrólise , Lisofosfolipídeos/análise , Lisofosfolipídeos/química , Fosfatidiletanolaminas/análise , Fosfatidiletanolaminas/química , Fosfatidilinositóis/análise , Fosfatidilinositóis/química , Fosfatidilserinas/análise , Fosfatidilserinas/química , Fosfolipídeos/química
4.
Tumour Biol ; 37(9): 11733-11741, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27020592

RESUMO

Long non-coding RNAs (lncRNAs) play a critical role in cancer progression, including in nasopharyngeal carcinoma (NPC). However, it is still poorly understood whether lncRNA regulates epithelial to mesenchymal transition (EMT) and radioresistance of NPC cells. We found that lncRNA NEAT1 was significantly upregulated in NPC cell lines and tissues. Knockdown of NEAT1 could sensitize NPC cells to radiation in vitro. Further investigation found that NEAT1 regulated radioresistance by modulating EMT phenotype. Furthermore, we found that there was reciprocal repression between NEAT1 and miR-204. ZEB1 was identified as a downstream target of miR-204 and NEAT1 upregulated ZEB1 expression by negatively regulating miR-204 expression. Taking together, we proposed that NEAT1 regulated EMT phenotype and radioresistance by modulating the miR-204/ZEB1 axis in NPC.


Assuntos
Transição Epitelial-Mesenquimal , MicroRNAs/fisiologia , Neoplasias Nasofaríngeas/patologia , RNA Longo não Codificante/fisiologia , Tolerância a Radiação , Homeobox 1 de Ligação a E-box em Dedo de Zinco/fisiologia , Adulto , Idoso , Carcinoma , Linhagem Celular Tumoral , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/radioterapia
5.
Med Phys ; 33(7): 2384-90, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16898440

RESUMO

As a quality control procedure, a post-implant seed migration survey has been accomplished on 340 prostate cancer patients since November 2001. Pulmonary seed embolization and intracardiac seed embolization have been detected. A case of thyroid uptake due to leaking iodine-125 (I-125) sources was also seized. In order to determine the dose to the thyroid, a dosimetry method was developed to link in vivo measurements and the cumulated dose to the thyroid. The calculated source leakage half-life in the case was approximately 15 days based on the measurements and the estimated cumulated dose to thyroid was 204 cGy. It is concluded that one seed was leaking. In order to verify the in vivo measurements, intentional in vitro seed leakage tests were performed. A seed was cut open and placed in a sealed glass container filled with a given volume of saline. The I-125 concentration in the saline was subsequently measured over a period of six months. Consistent in vivo and in vitro results were obtained. Recent incidents of seed leaks reported from other centers have drawn practitioners' attention to this problem. In order to make the measurements more useful, the seed leakage tests were expanded to include I-125 seeds from six other vendors. The results show that the leakage half-lives of those seeds varied from nine days to a half-year. Two seed models demonstrated least leakage. Since the measurements lasted for six months, the escape of iodine resulted from oxidation of iodide in the saline was a concern for the measurement accuracy. As a reference, another set of leakage tests were performed by adding sodium thiosulfate salt (Na2S2O3 x 5 H2O) to the saline. Sodium thiosulfate is a reducing agent that prevents the conversion of iodide to iodate so as to minimize I-125 evaporation. As a result, significantly shortened leakage half-lives were observed in this group. Seed agitation was also performed and no significant deviations of the leakage rates were observed. Considering the body fluid is more complex than saline, the in vivo leakage half-life, in case a source leak is encountered, may vary significantly from what is presented in this paper due to chemical reactions. In vivo measurements thus may produce a more accurate estimation of leakage half-life and thyroid uptake dose.


Assuntos
Braquiterapia/métodos , Radioisótopos do Iodo/farmacocinética , Neoplasias da Próstata/radioterapia , Radiometria/métodos , Compostos Radiofarmacêuticos/farmacocinética , Glândula Tireoide/efeitos da radiação , Humanos , Técnicas In Vitro , Masculino , Modelos Estatísticos , Dosagem Radioterapêutica
6.
J Urol ; 172(5 Pt 1): 1827-9, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15540731

RESUMO

PURPOSE: To decrease the seed migration rate after 125I prostate brachytherapy and improve the quality of implants to our knowledge we report for the first time the detection of thyroid uptake, possibly from a damaged seed, in a patient after 125I implantation. MATERIALS AND METHODS: Seed migration detection is routinely offered to our patients at the post-evaluation visit. A seed migration detector and comprehensive investigation procedure have been developed for the task. Chest radiographs are ordered to document the location of the detected seed. A fluoroscopic study may be performed if intracardiac radioactivity is detected. RESULTS: Since November 2001, 246 patients have been studied for seed migration. A total of 23,184 125I seeds were implanted, of which 75 were lost through the urethra and 25 migrated to the thorax. In the routine survey of a patient on February 13, 2003 radioactivity in the chest-neck region was sensed. Repeat radiographs and fluoroscopic examinations were negative for seed migration. Using a gamma camera butterfly-shaped uptake was noted in the thyroid region. The energy peak of the uptake matched the spectrum of the 125I source. The patient denied any intake of other iodine medication. The results suggested possible 125I leakage from at least 1 seed implanted in the prostatic region. CONCLUSIONS: Improved control of seed migration has been achieved. The detection of thyroid uptake is reported. Detection techniques and subsequent actions are described.


Assuntos
Braquiterapia/efeitos adversos , Migração de Corpo Estranho , Radioisótopos do Iodo/farmacocinética , Neoplasias da Próstata/radioterapia , Glândula Tireoide/metabolismo , Humanos , Masculino , Cintilografia , Glândula Tireoide/diagnóstico por imagem
7.
Int J Radiat Oncol Biol Phys ; 58(3): 888-91, 2004 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-14967446

RESUMO

PURPOSE: The purpose of this investigation is to determine the mechanism of seed migration after prostate implant and to develop procedures to minimize the risk of seed migration. METHODS AND MATERIALS: Radioactivity survey of prostate cancer patients after permanent brachytherapy with (125)I to detect pulmonary seed embolization is routinely performed using a seed migration detector. The seed migration detector is made from a low-energy, high-sensitivity scintillation survey meter by adding a single-hole collimation cap to the scintillation probe. If a seed migration is suspected, a pair of chest radiographs is ordered to document the location of the migrated seed. A comprehensive investigation is elicited if there are discrepancies between the seed migration detector survey and the radiographic examination. RESULTS: One hundred five patients have been surveyed, and 20 patients have demonstrated pulmonary seed embolization. In 1 patient, the seed migration detector sensed radioactivity in the thorax, but repeat chest radiographic examinations failed to show a radiopaque foreign body in the chest cavity. Owing to the signal variation mimicking heart rate, an (125)I seed located in the intracardiac region was suspected. This suspicion was confirmed in a high-quality fluoroscopy examination. CONCLUSIONS: Seed embolization to the intracardiac region is rarely reported. The true rate may be higher, but has not been adequately documented owing to the limitation of diagnostic quality of chest radiographs to detect seed migration to the intracardiac region. The seed migration detector, on the other hand, demonstrated its efficacy in the detection of seed migration, particularly in the detection of a seed located in the intracardiac region.


Assuntos
Braquiterapia/instrumentação , Corpos Estranhos/diagnóstico por imagem , Coração , Radioisótopos do Iodo , Neoplasias da Próstata/radioterapia , Idoso , Migração de Corpo Estranho/prevenção & controle , Humanos , Masculino , Radiografia , Cintilografia , Dosagem Radioterapêutica
8.
Med Phys ; 30(5): 785-90, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12772985

RESUMO

Pulmonary seed embolization is frequently observed in permanent prostate brachytherapy. Postoperative chest radiographic examination does not always detect seed embolization. To overcome this deficiency, a low energy gamma scintillation survey meter was converted to a seed-migration detector by adding a cone-shaped single-hole collimation cap to the window end of the scintillation probe. The response functions of the seed-migration detector to iodine-125 (I-125) for different source-to-detector distances in air and in water were measured. The spatial discrimination power of the survey meter, represented by the full width at half maximum measured in water, is typically improved from more than 7 cm to about 3 cm. Seventy-nine patients with I-125 implantation were scanned with the seed-migration detector at the patients' 30-day postevaluation visit. Fifteen patients showed single-seed embolization to the chest region and four patients displayed two-seed embolization. In other words, 24% of the patients present with embolized seeds. The detection accuracy of each patient was validated by a comprehensive investigation procedure. The comprehensive investigation consists of reviewing the patient's treatment history, orally questioning the patient for possible seed loss via the urethra route outside the hospital, examining all available chest radiographs before and after the seed implantation, and counting the seeds on the postevaluation CT scans. In comparison, examinations relying only on the analysis of postoperative chest radiographs yielded a false-positive detection in four patients and a false-negative detection in two patients. Another advantage of the seed-migration detector is that multiple seed-migration scans can be performed without exposing the patient to any additional radiation, for this device is a passive detector. Our clinical implementation also demonstrated that the seed-migration detector is a convenient and cost-effective method. As a result of this study, we stopped ordering the postoperative chest radiographs in a patient's regular postevaluation visit. Only if the detector shows radioactivity outside a patient's pelvis are a pair of anteroposterior and lateral chest radiographs of the patient ordered to document the location of the embolized seeds.


Assuntos
Braquiterapia/efeitos adversos , Braquiterapia/instrumentação , Migração de Corpo Estranho/diagnóstico , Radioisótopos do Iodo/uso terapêutico , Pulmão , Neoplasias da Próstata/radioterapia , Contagem de Cintilação , Raios gama , Humanos , Masculino , Neoplasias da Próstata/complicações , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
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