Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 79
Filtrar
Más filtros

Banco de datos
País/Región como asunto
Tipo del documento
País de afiliación
Intervalo de año de publicación
1.
Shokuhin Eiseigaku Zasshi ; 64(4): 145-153, 2023.
Artículo en Japonés | MEDLINE | ID: mdl-37673604

RESUMEN

We determined the fifteen types of plasticizers, including four kinds of phthalic acid esters (PAEs) used in 220 polyvinyl chloride (PVC) toys on Japanese market from 2019 to 2020. Three kinds of previously undetected types of PAEs were also detected, but not identified in this study. Di (2-ethylhexyl) terephthalate (DEHTP) was the highest detection rate in 209 soft PVC toys out of 220 toys, with 71.2% for designated toys and 88.9% for not-designated toys, respectively, showing a gradual increase from the previous reports in 2009 and 2014. On the other hand, the usages of o-acetyl tributyl citrate and adipic acid esters decreased, but the six types of PAEs prohibited to use for the designated toys in Japan were not detected in them, the usage of diisobutyl phthalate were increased. In contrast, four types of PAEs were detected in not-designated toys. Among them, the detection ratio of di (2-ethyhexyl) phthalate decreased to about 1/10. The content levels of plasticizers in per each sample were continued to keep low level from the report five years ago. These results showed that the main plasticizer used in PVC toys is DEHTP, and that the usage of other plasticizers was decreased.


Asunto(s)
Plastificantes , Cloruro de Polivinilo , Ésteres , Japón
2.
Shokuhin Eiseigaku Zasshi ; 64(3): 111-115, 2023.
Artículo en Japonés | MEDLINE | ID: mdl-37380481

RESUMEN

A validation study was performed on the modified analytical method for the migration solution of heptane, 20% ethanol and 4% acetic acid for the determination of bisphenol A migrating from polycarbonate food apparatuses, containers, and packaging. The analytes for the method were bisphenol A, phenol and p-tert-butylphenol. The repeatability, within-laboratory reproducibility and trueness of the method was estimated in the range of 0.2-1.8%, 0.4-2.6% and 95-102% respectively. These results showed that the method is useful as an analytical method for the migration solution of heptane, 20% ethanol and 4% acetic acid. Furthermore, the applicability of the determination methods with a fluorescence detector was verified. As a result of the validation study, the repeatability, within-laboratory reproducibility and trueness of the method was estimated in the range of 0.1-2.9%, 0.2-3.1% and 94-101% respectively. It was confirmed that the measurement with a fluorescence detector is also available.


Asunto(s)
Ácido Acético , Fenoles , Reproducibilidad de los Resultados , Etanol , Heptanos
3.
Shokuhin Eiseigaku Zasshi ; 64(4): 154-160, 2023.
Artículo en Japonés | MEDLINE | ID: mdl-37673605

RESUMEN

An inter-laboratory study involving 24 laboratories was conducted to validate the modified analytical method for the migration solution of heptane for the determination of bisphenol A migrating from polycarbonate food processing materials. In this study, two concentrations of samples were blindly coded. Each laboratory determined the analyte (bisphenol A, phenol and p-tert-butylphenol) concentration in each sample according to the established protocol. The obtained values were analyzed statistically using internationally accepted guidelines. Horwitz ratios were calculated based on the reproducibility relative standard deviation (RSDR), which was estimated from the inter-laboratory study, and predicted RSDR, which was calculated using the Horwitz/Thompson equation. Horwitz ratios of the two samples ranged from 0.15 to 0.37 for the three compounds, meeting the performance criteria of less than 2 set by the Codex Alimentarius for analytical method approval. These results showed that this modified analytical method shows good performance as an analytical method for the migration solution of heptane.


Asunto(s)
Heptanos , Fenoles , Reproducibilidad de los Resultados
4.
Shokuhin Eiseigaku Zasshi ; 63(2): 97-103, 2022.
Artículo en Japonés | MEDLINE | ID: mdl-35650035

RESUMEN

We modified a method for determining methanol content in detergents used in kitchens. Furthermore, an inter-laboratory study was conducted in 10 laboratories to validate the modified method. In this study, two concentrations of samples were blindly coded. Each laboratory determined the methanol content in each sample according to a protocol. The determined values were statistically analyzed according to an international harmonized guideline. HorRat values were calculated based on the reproducibility relative standard deviation (RSDR) which was estimated from the interlaboratory study, and predicted RSDR calculated from the Horwitz/Thompson equation. The HorRat values of the two samples were 0.8 and 1.8, meeting the performance criteria of less than 2 set by the Codex Alimentarius for analytical method approval. These results confirm that this modified analytical method shows good performance as an analytical method for determining methanol content in kitchen detergents.


Asunto(s)
Detergentes , Metanol , Laboratorios , Reproducibilidad de los Resultados
5.
Shokuhin Eiseigaku Zasshi ; 63(2): 51-61, 2022.
Artículo en Japonés | MEDLINE | ID: mdl-35650029

RESUMEN

Migration test of food utensils, containers, and packaging is an important test method for confirming the safety and their compliance to the standards. However, there is little report on inter-laboratory study which was performed to evaluate the entire migration test, including migration operations and quantification. An interlaboratory study was performed participating 22 laboratories using 8 types of model synthetic resin samples containing 10 substances with a wide range of Log Pow values to evaluate the accuracy of the entire migration test. As a result, most of HorRat (r) values met the target criteria (0.3

Asunto(s)
Contaminación de Alimentos , Plásticos , Contaminación de Alimentos/análisis , Embalaje de Alimentos , Laboratorios
6.
Rapid Commun Mass Spectrom ; 34 Suppl 2: e8707, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31883162

RESUMEN

RATIONALE: Polyamide (PA) is the generic name of polymers synthesized by linking monomers via amide bonds, and various types of PAs with different monomer compositions are known. Distinguishing PA polymers is useful in directing monomer residual testing, product testing, and reverse engineering, but is analytically challenging and cumbersome. To simplify this, we explored the applicability of direct analysis in real time mass spectrometry (DART-MS) for screening PA polymers. METHODS: A DART ion source coupled to a quadrupole Orbitrap (high-resolution (HR) mass spectrometer) was employed for this study. Ten types of PA polymers and four retail samples were evaluated. The DART-HRMS data for these samples, as well as the DART-MS/MS (MS2 ) data for PA6 and PA66, were obtained, and their repeatability was assessed across days/calibrations, operators, and equipments. RESULTS: Ions corresponding to the cyclic or linear monomers and oligomers of each PA polymer were detected in each DART-HR mass spectrum. Although similar DART-HR mass spectra were obtained for PA6, PA66, and PA6/PA66 (polymer blends of PA6 and PA66), their DART tandem mass spectra were completely different. The analysis was repeatable, and nearly identical DART tandem mass spectra were obtained on different days, by different operators, and with different equipment. This technique was successfully applied to commercially available samples. CONCLUSIONS: Ten types of PA polymers were distinguished using DART-HRMS and DART-MS2 , and their identification using these techniques was straightforward as the characteristic ions for each PA polymer were identified and detected. Furthermore, the spectra were obtained rapidly. Therefore, DART-HRMS can be considered an efficient screening technique for the rapid identification and differentiation of PA polymers.

7.
Nature ; 497(7451): 607-10, 2013 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-23719462

RESUMEN

Understanding the origins of the diversity in terrestrial planets is a fundamental goal in Earth and planetary sciences. In the Solar System, Venus has a similar size and bulk composition to those of Earth, but it lacks water. Because a richer variety of exoplanets is expected to be discovered, prediction of their atmospheres and surface environments requires a general framework for planetary evolution. Here we show that terrestrial planets can be divided into two distinct types on the basis of their evolutionary history during solidification from the initially hot molten state expected from the standard formation model. Even if, apart from their orbits, they were identical just after formation, the solidified planets can have different characteristics. A type I planet, which is formed beyond a certain critical distance from the host star, solidifies within several million years. If the planet acquires water during formation, most of this water is retained and forms the earliest oceans. In contrast, on a type II planet, which is formed inside the critical distance, a magma ocean can be sustained for longer, even with a larger initial amount of water. Its duration could be as long as 100 million years if the planet is formed together with a mass of water comparable to the total inventory of the modern Earth. Hydrodynamic escape desiccates type II planets during the slow solidification process. Although Earth is categorized as type I, it is not clear which type Venus is because its orbital distance is close to the critical distance. However, because the dryness of the surface and mantle predicted for type II planets is consistent with the characteristics of Venus, it may be representative of type II planets. Also, future observations may have a chance to detect not only terrestrial exoplanets covered with water ocean but also those covered with magma ocean around a young star.

8.
Shokuhin Eiseigaku Zasshi ; 60(3): 38-44, 2019.
Artículo en Japonés | MEDLINE | ID: mdl-31391409

RESUMEN

Analytical survey of plasticizers used in about 500 polyvinyl chloride (PVC) toys in Japanese market was performed in 2014. The results obtained were compared with those obtained in 2009. Fifteen types of plasticizers including di (2-ethylhexyl) terephthalate (DEHTP) were detected. These plasticizers were also detected in the products in 2009, suggesting that the types of plasticizers used in PVC toys have not been changed. Among these detected plasticizers, the detection ratios of DEHTP were 60.3 and 73.7% in both designated and not-designated toys, respectively, both of which are the highest. These ratios are over 20-points higher than those in 2009. The six types of phthalic acid esters (PAEs) prohibited to use for the designated toys in Japan were not detected in designated toys used in this study. However, four types of PAEs, including three types of prohibited PAEs, were detected in not-designated toys with the detection ratios from 2.8 to 15.5%. These ratios are lower than those in 2009. The content levels of plasticizers used in the toys are lower than those in 2009. These results show that the main plasticizer used in PVC toys is DEHTP, and that the usage levels of plasticizers have been decreased.


Asunto(s)
Plastificantes/análisis , Juego e Implementos de Juego , Cloruro de Polivinilo/análisis , Japón
9.
Shokuhin Eiseigaku Zasshi ; 60(4): 73-81, 2019.
Artículo en Japonés | MEDLINE | ID: mdl-31474654

RESUMEN

Multilayer laminated films may contain organic solvents derived from adhesives, printing inks and so on. A headspace-GC/MS analysis method for the simultaneous determination of 30 substances such as toluene, xylene, acetone, methyl ethyl ketone, ethyl acetate, butyl acetate, methanol, ethanol, was developed. A N,N-dimethyl formamide solution containing an internal standard substance was added to the sample. After leaving overnight at room temperature, the headspace gas was analyzed by GC/MS. This method was applicable to a laminate film made of various materials. The organic solvents such as toluene, ethyl acetate, and heptane were detected from 6 out of 42 food packaging bags made from laminated film on Japanese market using this method.


Asunto(s)
Embalaje de Alimentos , Cromatografía de Gases y Espectrometría de Masas , Solventes/análisis
10.
Gan To Kagaku Ryoho ; 46(13): 2264-2266, 2019 Dec.
Artículo en Japonés | MEDLINE | ID: mdl-32156899

RESUMEN

A 72-year-old man presented with right lower abdominal pain. Abdominal enhanced CT showed a large tumor in the ascending colon. Colonoscopyrevealed a type 2 tumor infiltrating three-quarters of the ascending colon. The biopsyspecimen showed a malignant lymphoma. Thus, the patient underwent ileocecal resection with D3 lymph node dissection. The histopathological diagnosis was primarydiffuse large B-cell lymphoma of the ascending colon. Post-operative PET-CT showed disseminated extra-nodal involvement, Stage Ⅳ(Lugano staging system). He was administered 2 courses of rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisolone chemotherapy. However, the patient was diagnosed with progressive disease. He received several chemotherapies and finallydied 8 months after surgery. We report our present case and literature review.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Colon Ascendente , Neoplasias del Colon , Linfoma de Células B Grandes Difuso , Anciano , Neoplasias del Colon/diagnóstico por imagen , Neoplasias del Colon/tratamiento farmacológico , Ciclofosfamida , Doxorrubicina , Humanos , Linfoma de Células B Grandes Difuso/diagnóstico por imagen , Linfoma de Células B Grandes Difuso/tratamiento farmacológico , Masculino , Tomografía Computarizada por Tomografía de Emisión de Positrones , Prednisona , Rituximab , Vincristina
11.
Langmuir ; 34(46): 13979-13992, 2018 11 20.
Artículo en Inglés | MEDLINE | ID: mdl-30412406

RESUMEN

The hydrolysis mechanisms of 2-sulfoalkanoic acid methyl ester salts (methyl ester sulfonate, MES) were studied. Under acidic, neutral, and alkaline conditions, the hydrolysis rates of MES were strongly affected by the state of aggregation and the hydrolysis rate changed at the critical micelle concentration (CMC). Under acidic conditions, the hydrolysis rates of MES were enhanced by micellar formation and correlated quantitatively with the amount of protons bound on the micellar surfaces being measured by the electric conductivity along with fluorescence and hydrogen-ion electrode measurements. MES having longer acyl chain lengths showed higher hydrolysis rates above the CMC because of the many bound protons and the higher degree of counterion binding to the micelle, ß. The rates were affected by the type of counterion and followed the order of sodium > potassium > calcium salts of MES. In alkaline conditions, the rates of MES hydrolysis were suppressed to lower values by micelle formation and MES with longer acyl chain lengths showed lower rates above the CMC. Additionally, the hydrolysis rates of MES under neutral conditions were suppressed to a very low value by micelle formation. These mechanisms of inhibitory effect of hydrolysis by the aggregation should be dominated by the electrical repulsive interactions between hydroxyl anions and anionic micellar surfaces, as well as by interference with the penetration of the hydroxyl anion to the ester group in the micelles for alkaline hydrolysis and by interference from water molecules for neutral hydrolysis.

12.
Shokuhin Eiseigaku Zasshi ; 59(5): 193-199, 2018.
Artículo en Japonés | MEDLINE | ID: mdl-30429416

RESUMEN

The evaporation residue test designated in the Japanese Food Sanitation Act is used to determine the total migration amount of substances that food contact materials release into foods. Vegetable oil would be the most suitable food simulant for oils and fatty foods, but it is difficult to remove by heating due to its high boiling point, so heptane and 20% ethanol are used as substitute food simulants in the test for plastics and rubbers. The EU has introduced an overall migration test into olive oil for plastics intended to come into contact with oils and fatty foods. This test method is described in European Standard EN1186-2. However, this method has several problems. Therefore, we improved the procedures for weighing samples in a desiccator containing 43% sulfuric acid, extraction of the absorbed vegetable oil using the soaking method with an internal standard, methyl esterification of vegetable oil using sodium methoxide, and the GC conditions for the determination of vegetable oil. The improved method is simpler and much quicker than the original method, and the harmfulness of the reagents is reduced. It can be applied to both plastics and rubbers. Comparative trials showed that the results obtained with this method and EN1186-2 method are equivalent.


Asunto(s)
Contaminación de Alimentos , Embalaje de Alimentos , Aceites de Plantas/análisis , Plásticos
13.
J Nucl Cardiol ; 24(5): 1725-1736, 2017 10.
Artículo en Inglés | MEDLINE | ID: mdl-27251143

RESUMEN

BACKGROUND: Septal penetration causes collimator-dependent differences in the heart-to-mediastinum (H/M) ratio in 123I-metaiodobenzylguanidine (MIBG) cardiac imaging. We investigated generally applicable methods to correct such differences. METHODS AND RESULTS: Four hours after 123I-MIBG injection, 40 patients underwent anterior chest imaging successively with medium-energy (ME) and various non-ME collimators. The H/M ratios obtained with the non-ME collimators before and after 123I-dual-window penetration correction were compared with the ME-derived standard values to determine patient-based conversion equations for empiric and combined corrections, respectively. A 123I point source was imaged with various collimators, and the central ratio, the ratio of count in a small central region of interest to count in a large one, was calculated. The method of predicting the conversion equations from the central ratios was determined. Correction using the patient-based conversion equations removed systematic underestimation of the H/M ratios obtained with the non-ME collimators, and combined correction depressed residual random errors to some degree. Point-source-based equations yielded results comparable to the patient-based equations. CONCLUSIONS: Empiric and combined corrections effectively reduce collimator-dependent differences in the H/M ratio. The conversion equations can be predicted from simple point-source imaging, which would allow to apply these corrections to data obtained with various collimators.


Asunto(s)
3-Yodobencilguanidina , Técnicas de Imagen Cardíaca , Corazón/diagnóstico por imagen , Radioisótopos de Yodo/química , Mediastino/diagnóstico por imagen , Anciano , Anciano de 80 o más Años , Algoritmos , Diagnóstico por Computador , Femenino , Humanos , Masculino , Persona de Mediana Edad , Miocardio , Cintigrafía , Radiofármacos
14.
J Comput Assist Tomogr ; 41(5): 688-695, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28448406

RESUMEN

OBJECTIVE: We assessed the feasibility of T1-weighted 2-dimensional spoiled gradient-recalled (2D SPGR) acquisition in steady-state imaging of the liver with various respiratory navigator gating techniques. METHODS: A total of 12 healthy volunteers underwent in-phase and out-of-phase 2D SPGR imaging of the liver during breath-holding and free-breathing. Four techniques for respiratory navigation, 2 conventional navigator techniques and 2 self-navigator techniques, were used for free-breathing imaging. RESULTS: Good navigator waveforms were obtained in conventional navigation, whereas fluctuations were evident in self navigation. All of the 4 navigator-based methods provided better images in terms of background signals and visual image quality compared with images obtained with no respiratory control. However, differences remained in comparison with breath-holding. Superiority of self-navigation to conventional navigation was not shown. CONCLUSIONS: Navigator-gating techniques improved 2D SPGR images of the liver acquired during free-breathing, suggesting feasibility and beneficial effects, although navigator-based images were still inferior to breath-hold images.


Asunto(s)
Procesamiento de Imagen Asistido por Computador/métodos , Hígado/anatomía & histología , Imagen por Resonancia Magnética/métodos , Técnicas de Imagen Sincronizada Respiratorias/métodos , Adulto , Contencion de la Respiración , Estudios de Factibilidad , Femenino , Humanos , Masculino , Valores de Referencia , Respiración
15.
Kaku Igaku ; 54(1): 545-549, 2017.
Artículo en Japonés | MEDLINE | ID: mdl-28804109

RESUMEN

Low-energy characteristic x-rays emitted by 111In and 123I sources are easily absorbed by the containers of the sources, affecting radioactivity measurements using a dose calibrator. We examined the effects of different containers on the estimated activities. The radioactivities of 111In, 123I, 201Tl, and 99mTc were measured in containers frequently employed in clinical practice in Japan. The 111In measurements were performed in the vials A and B of the 111In-pentetreotide preparation kit and in the plastic syringe. The activities of 123I-metaiodobenzylguanidine and 201Tl chloride were measured in the prefilled glass syringes and plastic syringes. The milking vial, vial A, vial B, and plastic syringe were used to assay 99mTc. For 111In and 123I, measurements were performed with and without a copper filter. The filter was inserted into the well of the dose calibrator to absorb low-energy x-rays. The relative estimate was defined as the ratio of the activity estimated with the dose calibrator to the standard activity. The estimated activities varied greatly depending on the container when 111In and 123I sources were assayed without the copper filter. The relative estimates of 111In were 0.908, 1.072, and 1.373 in the vial A, vial B, and plastic syringe, respectively. The relative estimates of 123I were 1.052 and 1.352 in the glass syringe and plastic syringe, respectively. Use of the copper filter eliminated the container-dependence in 111In and 123I measurements. Container-dependence was demonstrated in neither 201Tl nor 99mTc measurements. The activities of 111In and 123I estimated with a dose calibrator differ greatly among the containers. Accurate estimation may be attained using the container-specific correction factor or using the copper filter.


Asunto(s)
Radioisótopos de Indio , Radioisótopos de Yodo , Radiactividad , Radiofármacos , Calibración , Japón , Radioisótopos , Estándares de Referencia , Jeringas , Radioisótopos de Talio
16.
Gan To Kagaku Ryoho ; 43(3): 373-5, 2016 Mar.
Artículo en Japonés | MEDLINE | ID: mdl-27067859

RESUMEN

The recommended regimen for S-1 internal use is 4 weeks of daily medication and 2 weeks of drug holiday. However, we experience many cases where changing the regimen is ineffective because of adverse events. This time, we report a favorable case of alternate-day treatment with S-1 in an elderly patient with multiple lung metastases of colon cancer. An 84-year-old woman, performance status 2, was diagnosed as having colon cancer and multiple lung metastases. After operation of the colon, she received chemotherapy with the S-1 alternate-day treatment. The lung metastases decreased remarkably, and she was able to continue the treatment without significant adverse events. She has been receiving the treatment without progression for more than 18 months now. The alternate-day treatment with S-1 is reported as a cure with anticancer efficacy and few adverse events. This treatment seems to be a useful chemotherapy for elderly patients with colon cancer.


Asunto(s)
Antimetabolitos Antineoplásicos/uso terapéutico , Neoplasias del Colon/tratamiento farmacológico , Neoplasias Pulmonares/tratamiento farmacológico , Ácido Oxónico/uso terapéutico , Tegafur/uso terapéutico , Anciano de 80 o más Años , Antimetabolitos Antineoplásicos/administración & dosificación , Quimioterapia Adyuvante , Neoplasias del Colon/patología , Neoplasias del Colon/cirugía , Combinación de Medicamentos , Femenino , Humanos , Neoplasias Pulmonares/secundario , Ácido Oxónico/administración & dosificación , Tegafur/administración & dosificación , Resultado del Tratamiento
17.
Gan To Kagaku Ryoho ; 43(1): 103-6, 2016 Jan.
Artículo en Japonés | MEDLINE | ID: mdl-26809535

RESUMEN

A 42-year-old woman visited our hospital with high fever and general malaise. A CT examination revealed that she had carcinoma of the left breast with axillary lymph node metastases and multiple bone metastases. A blood test showed anemia, thrombopenia and the existence of blast-like cells. Adenocarcinoma cells were detected in a bone marrow aspiration specimen, and the patient was diagnosed with disseminated carcinomatosis of the bone marrow. Systemic chemotherapy with paclitaxel plus bevacizumab was initiated while a blood transfusion was performed. Her symptoms improved, and the blood test results normalized. Disseminated carcinomatosis of the bone marrow is reported to have a poor prognosis, but paclitaxel plus bevacizumab is a possible effective chemotherapy.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias de la Médula Ósea/tratamiento farmacológico , Neoplasias de la Mama/tratamiento farmacológico , Adulto , Bevacizumab/administración & dosificación , Neoplasias de la Médula Ósea/secundario , Neoplasias de la Mama/patología , Femenino , Humanos , Paclitaxel/administración & dosificación , Resultado del Tratamiento
18.
J Nucl Cardiol ; 21(1): 71-7, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24150537

RESUMEN

BACKGROUND: Septal penetration of high-energy photons affects the estimation of the heart-to-mediastinum (H/M) ratio in cardiac (123)I-metaiodobenzylguanidine (MIBG) imaging, and the use of a medium-energy (ME) collimator has been shown to improve quantitative accuracy. We investigated the effect of septal penetration on the estimation of H/M ratios using an ME collimator. METHODS AND RESULTS: Point sources of (99m)Tc and (123)I were imaged using various collimators, which indicated that the effect of high-energy photons with the ME collimator was relatively small but larger than that with the high-energy (HE) collimator. Four hours after (123)I-MIBG injection, 20 patients underwent planar anterior chest imaging by different methods in succession. The ME collimator gave lower H/M ratios (mean 2.52) than the HE collimator (2.57), indicating influence of septal penetration in the ME collimator; however, the difference was limited. Although narrowing the energy window from 20% (2.51) to 15% (2.54) increased the H/M ratios in imaging with the ME collimator, the difference was quite limited. CONCLUSIONS: Septal penetration affects the estimation of the H/M ratios using an ME collimator; however, this influence is small and would not have clinical significance.


Asunto(s)
3-Yodobencilguanidina , Corazón/diagnóstico por imagen , Mediastino/diagnóstico por imagen , Anciano , Técnicas de Imagen Cardíaca , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Radioisótopos de Yodo , Masculino , Persona de Mediana Edad , Fotones , Cintigrafía , Radiofármacos , Tecnecio/química
19.
J Nucl Cardiol ; 21(3): 614-21, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24715623

RESUMEN

BACKGROUND: Septal penetration causes underestimation of the heart-to-mediastinum (H/M) ratio in cardiac (123)I-metaiodobenzylguanidine (MIBG) imaging with a low-energy high-resolution (LEHR) collimator. We aimed to improve the method of estimating the H/M ratios using the LEHR collimator. METHODS AND RESULTS: 4 hours after (123)I-MIBG injection, 40 patients were imaged successively with the medium-energy (ME) and LEHR collimators using gamma cameras having 3/8-inch crystals. Severe underestimation of the H/M ratios was observed with the LEHR collimator when compared to the ME collimator. Narrowing the energy window width did not reduce the underestimation. Application of (123)I-dual-window (IDW) correction using a narrow or wide subwindow reduced the underestimation substantially but not entirely. The H/M ratios estimated from the LEHR images with or without IDW correction were corrected based on their correlations with the ratios estimated from the ME images. This empiric correction removed systematic underestimation, and residual errors were reduced when the H/M ratios after IDW correction were converted using the empiric equation. The conversion equation was successfully applied to the correction of the H/M ratios determined in another 40 patients using a 5/8-inch crystal. CONCLUSIONS: In estimating the H/M ratios using an LEHR collimator, empiric correction combined with IDW correction improves concordance with ME-based values in comparison with empiric correction alone.


Asunto(s)
Insuficiencia Cardíaca/diagnóstico por imagen , Corazón/diagnóstico por imagen , Aumento de la Imagen/métodos , Interpretación de Imagen Asistida por Computador/instrumentación , Mediastino/diagnóstico por imagen , Cintigrafía/instrumentación , Sistema Nervioso Simpático/diagnóstico por imagen , 3-Yodobencilguanidina/farmacocinética , Algoritmos , Diseño de Equipo , Análisis de Falla de Equipo , Femenino , Insuficiencia Cardíaca/metabolismo , Humanos , Interpretación de Imagen Asistida por Computador/métodos , Masculino , Miocardio/metabolismo , Dosis de Radiación , Radiofármacos/farmacocinética , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Sistema Nervioso Simpático/metabolismo
20.
Plant Cell ; 22(10): 3374-89, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20971893

RESUMEN

Glucosylation of anthocyanin in carnations (Dianthus caryophyllus) and delphiniums (Delphinium grandiflorum) involves novel sugar donors, aromatic acyl-glucoses, in a reaction catalyzed by the enzymes acyl-glucose-dependent anthocyanin 5(7)-O-glucosyltransferase (AA5GT and AA7GT). The AA5GT enzyme was purified from carnation petals, and cDNAs encoding carnation Dc AA5GT and the delphinium homolog Dg AA7GT were isolated. Recombinant Dc AA5GT and Dg AA7GT proteins showed AA5GT and AA7GT activities in vitro. Although expression of Dc AA5GT in developing carnation petals was highest at early stages, AA5GT activity and anthocyanin accumulation continued to increase during later stages. Neither Dc AA5GT expression nor AA5GT activity was observed in the petals of mutant carnations; these petals accumulated anthocyanin lacking the glucosyl moiety at the 5 position. Transient expression of Dc AA5GT in petal cells of mutant carnations is expected to result in the transfer of a glucose moiety to the 5 position of anthocyanin. The amino acid sequences of Dc AA5GT and Dg AA7GT showed high similarity to glycoside hydrolase family 1 proteins, which typically act as ß-glycosidases. A phylogenetic analysis of the amino acid sequences suggested that other plant species are likely to have similar acyl-glucose-dependent glucosyltransferases.


Asunto(s)
Antocianinas/metabolismo , Delphinium/enzimología , Dianthus/enzimología , Flores/enzimología , Glucosiltransferasas/metabolismo , ADN Complementario/genética , Delphinium/genética , Dianthus/genética , Flores/genética , Glucosa/metabolismo , Glucosiltransferasas/genética , Datos de Secuencia Molecular , Filogenia
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA