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1.
Strahlenther Onkol ; 197(12): 1051-1062, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34673991

RESUMO

PURPOSE: Patients with locally advanced grade 2-3 extremity/truncal soft tissue sarcomas (STS) are at high risk of recurrence. The objective of this study was to assess the efficacy and feasibility of neoadjuvant concurrent chemoradiotherapy (cCRT) in selected grade 2-3 patients with limb or trunk wall STS, and to compare this schedule to a sequential approach combining neoadjuvant chemotherapy and adjuvant radiotherapy. METHODS: We retrospectively included patients who underwent neoadjuvant cCRT at two comprehensive cancer centers from 1992-2016. We then compared these results to those of patients treated with preoperative chemotherapy and postoperative radiotherapy from a third comprehensive cancer center with a propensity score matched analysis. RESULTS: A total of 53 patients were treated by neoadjuvant cCRT; 58 patients could be matched with 29 patients in each treatment group after propensity score matching. Disease-free survival and overall survival at 5 years were 54.9 and 63.5%, respectively with neoadjuvant cCRT, with no significant difference when compared to the sequential treatment group. R0 resection rate was higher (90.9 vs 44.8%, p < 0.01) in the cCRT group than in the sequential treatment group during a shorter therapeutic sequence (118 vs 210.5 days, p < 0.01), with no impact on the surgical procedure or postoperative complications. CONCLUSION: cCRT is feasible with acceptable immediate and late toxicities. It could facilitate surgery by increasing the R0 resection rate and improve patient compliance by shortening the therapeutic sequence.


Assuntos
Terapia Neoadjuvante , Sarcoma , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Quimiorradioterapia/métodos , Intervalo Livre de Doença , Extremidades/patologia , Humanos , Terapia Neoadjuvante/métodos , Estadiamento de Neoplasias , Estudos Retrospectivos , Sarcoma/patologia , Sarcoma/terapia , Resultado do Tratamento
2.
J Environ Radioact ; 235-236: 106624, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34059369

RESUMO

The inventories of 137Cs (503 ±â€¯34 Bq.m-2), 241Am (11.3 ±â€¯1.2 Bq.m-2), 241Pu (33.7 ±â€¯3.4 Bq.m-2), 238Pu (6.82 ±â€¯0.87 Bq.m-2) and 239+240Pu (113.0 ±â€¯5.9 Bq.m-2), sum of 239Pu (100 ±â€¯11 Bq.m-2) and 240Pu (14.5 ±â€¯1.7 Bq.m-2), in the Gambier archipelago (23°S) of the French Polynesia, are well higher the global fallout at this latitude, in unequal proportions for the different radionuclides. (240Pu/239Pu)AR (AR: atomic ratio) of 0.0394 ±â€¯0.0062, and (241Pu/239Pu)AR of (2.03 ±â€¯0.39)10-4, confirm that the overwhelmingly dominant source of these radionuclides comes from local fallout during the 1970s of the French atmospheric tests of Moruroa and Fangataufa located nearly 400 km from Gambier. The signatures of the local fallout were deduced from the excess of its inventory in 137Cs and from the mixing lines established from the signatures of the global fallout, some of the test sites and the isotopic ratios measured in Gambier. Signatures obtained are 2.0 ±â€¯0.4 for 137Cs/239+240Pu, 0.045 ±â€¯0.008 for 238Pu/239+240Pu, 0.031 ±â€¯0.009 for 241Am/239+240Pu, 0.092 ±â€¯0.027 for 241Pu/239+240Pu, 0.0163 ±â€¯0.0049 for (240Pu/239Pu)AR, (0.78 ±â€¯0.23)10-4 for (241Pu/239Pu)AR. The concordance of the mixing lines of the [(240Pu/239Pu)AR, (241Pu/239Pu)AR] and the linear regression of these ratios measured in the stratosphere (40°S) during the 1970s, indicates that the signatures of the close-in deposition are also those of the stratospheric injections of the French tests. The signatures of stratospheric fallout in the Southern Hemisphere were evaluated by considering that the fission energy of these injections represents 11% and that of the Northern Hemisphere represents 89% and that the isotopic ratios of stratospheric injections remained the same over the period 1970-1974. The activity ratios deducted are 21.9 ±â€¯0.1 in 137Cs/239+240Pu, 0.11 ±â€¯0.05 in 238Pu/239+240Pu, 1.03 ±â€¯0.12 in 241Pu/239+240Pu and 0.35 ±â€¯0.04 in 241Am/239+240Pu. The associated atom ratios are 0.157 ±â€¯0.011 for (240Pu/239Pu)AR and (8.33 ±â€¯0.48)10-4 for (241Pu/239Pu)AR. These signatures appear to be consistent with the results of the inventories at Hiva Oa, located more than 1,000 km north of both French test sites, and with those found in the Australian continent, in regions not impacted by UK-test debris. The proportions of close-in tropospheric fallout from the French tests are about 90% in Gambier. They represent a proportion in the inventories of 40% for the 137Cs, 60% for 241Am and in the range between 80 and 90% for Pu isotopes.


Assuntos
Plutônio , Monitoramento de Radiação , Cinza Radioativa , Austrália , Radioisótopos de Césio , Ilhas , Plutônio/análise , Polinésia , Cinza Radioativa/análise
3.
Gynecol Obstet Fertil Senol ; 49(2): 112-121, 2021 02.
Artigo em Francês | MEDLINE | ID: mdl-33130043

RESUMO

OBJECTIVE: Five to 7% of breast cancers affect women under 40 years old. The survival of these patients has been improved thanks to therapeutic advances, often to the detriment of their fertility. The objective of this study is to evaluate the activity of oncofertility and the future of young women with breast cancer managed at the Montpellier University Hospital. METHODS: This is a retrospective study including women aged from 18 to 43 years-old diagnosed with breast cancer and referred in oncofertility consultation at the Montpellier University Hospital between July 2011 and December 2018. RESULTS: 190 patients were eligible, three refused to participate to the study, hence 187 patients were included. We estimate that only 33% of young breast cancer patients potentially eligible for fertility preservation (FP) benefited from an oncofertility consultation in our region. Of these 187 patients, 58 (31%) underwent ovarian stimulation for oocyte or embryo vitrification. They were significantly younger: 32.9 vs 34.6 years old (P=0.01) and had fewer invaded lymph nodes. A total of 66 cycles were achieved and 11.4 oocytes or 3 embryos were vitrified per patient. The reuse rate was 3.6% with 91% of post cancer pregnancies being spontaneous. CONCLUSION: The oncofertility care network seems effective at the regional level. Enhancing health professionals' awareness and creating a regional register could improve our long-term follow-up.


Assuntos
Neoplasias da Mama , Preservação da Fertilidade , Adolescente , Adulto , Neoplasias da Mama/terapia , Feminino , Hospitais Universitários , Humanos , Gravidez , Estudos Retrospectivos , Vitrificação , Adulto Jovem
4.
J Environ Radioact ; 202: 1-7, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30771696

RESUMO

A new rapid protocol for 226Ra separation and preconcentration in natural water samples was developed before its determination by Inductively Coupled Plasma Mass Spectrometry (ICP-MS). For this purpose, the commercially available Ra specific resin AnaLig® Ra-01 was used. This resin shows a high selectivity for radium in a large range of acid concentrations and no affinity or possible elution of 226Ra interfering elements. The distribution coefficients of Ra and other elements over a wide range of acid (HCl and HNO3) concentrations were obtained. Due to the high radium selectivity, the new developed protocol uses only 50 mg of dry resin and its performance was evaluated using 100 mL of three natural waters with different ionic strengths, spiked with a known quantity of 226Ra. Radium was successfully separated and preconcentrated yielding recoveries ranging between 72% and 86%. In parallel with the characterisation of the resin sorption properties, a detailed study of polyatomic interferences was performed on our ICP-MS allowing to identify the prominent elements favouring interferences at m/z = 226. Furthermore, a 226Ra sensitivity comparison between different ICP-MS instruments and configurations was done in order to determine high sensitivity conditions for radium analysis.


Assuntos
Rádio (Elemento)/análise , Poluentes Radioativos da Água/análise , Espectrofotometria Atômica , Análise Espectral
5.
Eur J Cancer ; 56: 37-44, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26802529

RESUMO

At present, there is no standardised approach for the radiological evaluation of soft tissue sarcomas following radiotherapy (RT). This manuscript, produced by a European Organisation for Research and Treatment of Cancer-Soft Tissue and Bone Sarcoma Group (EORTC-STBSG) and Imaging Group endorsed task force, aims to propose standardisation of magnetic resonance imaging techniques and interpretation after neoadjuvant RT for routine use and within clinical trials.


Assuntos
Imageamento por Ressonância Magnética/normas , Radioterapia (Especialidade)/normas , Sarcoma/patologia , Sarcoma/radioterapia , Neoplasias de Tecidos Moles/patologia , Neoplasias de Tecidos Moles/radioterapia , Consenso , Humanos , Valor Preditivo dos Testes , Radioterapia Adjuvante/normas , Reprodutibilidade dos Testes , Resultado do Tratamento
6.
Anal Chim Acta ; 883: 109-16, 2015 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-26088783

RESUMO

Nuclear accidents occurred in latest years highlighted the difficulty to achieve, in a short time, the quantification of alpha and beta emitters. Indeed, most of the existing methods, though displaying excellent performances, can be very long, taking up to several weeks for some radioisotopes, such as (90)Sr. This study focuses on alpha and beta radioisotopes which could be accidentally released from nuclear installations and which could be measured by inductively coupled plasma mass spectrometer (ICP-MS). Indeed, a new and rapid separation method was developed for (234,235,236,238)U, (230,232)Th, (239,240)Pu, (237)Np, (241)Am and (90)Sr. The main objective was to minimize the duration of the separation protocol by the development of a unique radiochemical procedure with elution media compatible with ICP-MS measurements. Excellent performances were obtained with spiked river water samples. These performances are characterized by total yields exceeding 80% for all monitored radionuclides, as well as good reproducibility (RSD≤10%, n=12). The proposed radiochemical separation (including counting time) required less than 7h for a batch of 8 samples.


Assuntos
Elementos da Série Actinoide/análise , Espectrometria de Massas/métodos , Rios/química , Radioisótopos de Estrôncio/análise , Poluentes Radioativos da Água/análise , Elementos da Série Actinoide/isolamento & purificação , Limite de Detecção , Espectrometria de Massas/economia , Reprodutibilidade dos Testes , Radioisótopos de Estrôncio/isolamento & purificação , Fatores de Tempo , Poluentes Radioativos da Água/isolamento & purificação
7.
J Environ Radioact ; 141: 1-7, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25500060

RESUMO

Uranium and thorium isotopes were measured in cypress leaves, wheat grains and lettuce taken in the surroundings of the uranium conversion facility of Malvési (South of France). The comparison of activity levels and activity ratios (namely (238)U/(232)Th and (230)Th/(232)Th) in plants with those in aerosols taken at this site and plants taken far from it shows that aerosols emitted by the nuclear site (uranium releases in the atmosphere by stacks and (230)Th-rich particles emitted from artificial ponds collecting radioactive waste mud) accounts for the high activities recorded in the plant samples close to the site. The atmospheric deposition process onto the plants appears to be the dominant process in plant contamination. Dry deposition velocities of airborne uranium and thorium were measured as 4.6 × 10(-3) and 5.0 × 10(-3) m s(-1), respectively.


Assuntos
Poluentes Radioativos do Ar/metabolismo , Chamaecyparis/metabolismo , Exposição Ambiental , Lactuca/metabolismo , Tório/metabolismo , Triticum/metabolismo , Urânio/metabolismo , Poluentes Radioativos do Ar/análise , França , Folhas de Planta/metabolismo , Monitoramento de Radiação , Tório/análise , Urânio/análise
8.
Diabetes Metab ; 40(3): 211-4, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24656963

RESUMO

AIM: We compared post-breakfast closed-loop glucose control either matched with a carbohydrate-matching bolus or a weight-dependent bolus. METHODS: Twelve adults with type 1 diabetes consumed a 75 g CHO breakfast on two occasions. In random order, the breakfast was accompanied by a full carbohydrate-matching insulin bolus (8.30 U [7.50 U-11.50 U]) or a partial weight-dependent insulin bolus (0.047 U/kg; 3.45 U [2.95 U-3.75 U]). Postprandial glucose was regulated by sensor-responsive insulin and glucagon delivery. RESULTS: Glucose control after the weight-dependent bolus was safe and feasible (glucose values returned to pre-prandial levels after 5 h). However, 5-hr incremental area under the curve and percentage of time above 10 mmol/L were lower after the full bolus compared to the partial bolus (IAUC, 2.1 [0.8-4.2] mmol/L/hr vs 8.3 [6.5-11.4] mmol/L/hr; time in hyperglycaemia, 24% [6%-29%] vs 50% [25%-63%]; P < 0.001). CONCLUSIONS: Post-breakfast closed-loop glucose control without carbohydrate counting, but based on weight-dependent bolus is feasible but a carbohydrate-matching bolus provides better glucose control. CLINICAL TRIAL REGISTRY: NCT01519102.


Assuntos
Desjejum , Diabetes Mellitus Tipo 1/tratamento farmacológico , Carboidratos da Dieta/metabolismo , Hiperglicemia/tratamento farmacológico , Hipoglicemiantes/administração & dosagem , Insulina/administração & dosagem , Período Pós-Prandial , Adulto , Algoritmos , Biomarcadores/metabolismo , Glicemia/metabolismo , Canadá , Estudos Cross-Over , Diabetes Mellitus Tipo 1/metabolismo , Esquema de Medicação , Feminino , Humanos , Hiperglicemia/metabolismo , Masculino , Pâncreas Artificial , Resultado do Tratamento
9.
J Environ Monit ; 14(11): 2902-12, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23001397

RESUMO

The activity concentrations of radionuclides within the uranium and thorium series were determined in wheat and lettuce at five sites in France, and in their respective potential sources: crop soils of wheat and crop soils and irrigation waters of lettuce. These data were used to calculate concentration ratios and to enrich the database supported by the technical report series N°472 of the IAEA (2010). For wheat and lettuce, the activity concentrations were in the same range for all radionuclides studied, except for (210)Pb, which had higher activity concentrations in wheat, ranging between 1.3 and 11 Bq kg(−1) (fresh weight) as compared to 0.4 and 0.7 Bq kg(−1) (fresh weight) for lettuce. For wheat, the range of activity concentrations (mBq kg(−1); fresh weight) decreased as (210)Pb > (226)Ra (56­1511) ≈ (228)Ra (86­769) > (228)Th (19­176) ≈ (238)U (11­169) ≈ (234)U (12­150) ≈ (230)Th (9.08­197.18) ≈ (232)Th (8.61­121.45) > (235)U (0.53­7.9). For lettuce, it decreased as (228)Ra (<320­1221) > (210)Pb (409­746) > (226)Ra (30­599) ≈ (228)Th (<29­347) > (238)U (8­120) ≈ (234)U (8­121) ≈ (230)Th (5.21­134.63) ≈ (232)Th (5.25­156.99) > (235)U (0.35­5.63). The species differences may reflect different plant physiologies. Through the study of activity ratios of wheat and lettuce in relation with those of the various radionuclide sources it has been possible to highlight the contribution of the main sources of natural radionuclides. Indeed, irrigation water when the uranium concentration is enhanced (>30 mBq L(−1)) contributed significantly to the activity concentration of uranium in lettuces. Concerning the high activity concentrations of (210)Pb, it could be explained by atmospheric particle deposition. The effect of soil particles resuspension and their adhesion to the plant surface seemed to be important in some cases. The soil-to-plant transfer factors were calculated for lettuce and wheat. The values were lower in wheat than in lettuce except for (210)Pb which had similar values in the two species (0.11­0.13 respectively). For both species, (210)Pb followed by (228)Ra (0.015­0.10) and (226)Ra (0.010­0.051) displayed the highest transfer factor, whereas (238)U had intermediate values (0.0015­0.030) and (232)Th exhibited the lowest (0.0014­0.013).


Assuntos
Lactuca/química , Monitoramento de Radiação/métodos , Poluentes Radioativos do Solo/análise , Tório/análise , Triticum/química , Urânio/análise , França
10.
J Environ Monit ; 14(8): 2170-80, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22689007

RESUMO

Activity concentrations of the uranium and thorium series radionuclides were determined in chicken meat and eggs as well as in soil, water and other dietary intakes of poultry at five sites of the French territory. These data allow the calculation of transfer coefficients which enrich the database given by the technical report series no. 472 of the IAEA. In egg contents, the highest activity concentrations (in mBq kg(-1) fresh weight) are for (226)Ra, ranging between 136 and 190 and are much lower for uranium (between 0.51 and 1.30 for (238)U). In chicken meat, (238)U activity concentration is higher than in egg contents and ranges between 1.7 and 9.7. Concerning (232)Th, its activity concentration is lower than uranium and ranges between 0.5 and 4.9. Daily ingested activity concentration by the animals was assessed taking into account the activity concentrations measured in the grains, in the soil and in the drinking water. The activity concentration in grains and the daily intakes allow the calculation of concentration ratios and transfer coefficients for chicken meat and egg contents. In chicken meat the transfer coefficients (d kg(-1)) range between 0.0018 and 0.0073 for (238)U and between 0.0008 and 0.0028 for (232)Th. In egg contents they range from 0.00018 to 0.0018 for (238)U and are much higher for radium isotopes (0.10-0.23 for (226)Ra and 0.07-0.11 for (228)Ra).


Assuntos
Grão Comestível/química , Carne/análise , Óvulo/química , Poluentes Radioativos do Solo/análise , Tório/análise , Urânio/análise , Animais , Galinhas , Água Potável/química , Contaminação de Alimentos/análise , Água Doce/química , Modelos Químicos , Solo/química
11.
J Environ Monit ; 13(5): 1327-36, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21487575

RESUMO

Cypress needles collected at the edge of the Malvési uranium facility (SW France) exhibit enhanced activities of actinides and some decay products (uranium, americium, plutonium, (230)Th, (226)Ra) compared to a remote site. These enhanced activities resulted from the release of U via smokestacks and passive release from former artificial ponds located inside the nuclear site. Enhanced activities are also observed in selected produce (wheat, lettuce, fruits) sampled from the edge of the site. However, excess actinides measured in wheat grains in 2007 are inconsistent with the activities and the uranium ratio measured in the soils. This result suggests that the studied annual crops were contaminated mainly through the short-term release of airborne actinides, and that other transfer pathways, such as, uptake through the roots or adhesion of soil particles, were negligible.


Assuntos
Elementos da Série Actinoide/análise , Produtos Agrícolas/química , Poluentes Radioativos/análise , Cupressus/química , Exposição Ambiental/análise , Exposição Ambiental/estatística & dados numéricos , Humanos , Folhas de Planta/química , Monitoramento de Radiação
12.
J Environ Monit ; 13(2): 355-61, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21132170

RESUMO

Uranium and plutonium isotopes were measured in soils, sediments and waters in an area subject to the past and present discharges from the uranium conversion plant of Malvési (France). The isotopes (236)U and (239)Pu are well known activation products of uranium and they prove to be powerful tracers of spent fuel releases in soils and sediments. On the other hand (234)U and (238)U activities measured in waters can be used to distinguish between releases and background uranium sources. Such findings contribute to improve the monitoring of the actinides releases by nuclear fuel facilities (mining sites, conversion, enrichment and fuel plants, reprocessing plants).


Assuntos
Monitoramento Ambiental/métodos , Água Doce/análise , Sedimentos Geológicos/análise , Plutônio/análise , Poluentes Radioativos do Solo/análise , Solo/análise , Urânio/análise , Elementos da Série Actinoide/análise , França , Reatores Nucleares
13.
J Radiol ; 91(9 Pt 2): 935-49, 2010 Sep.
Artigo em Francês | MEDLINE | ID: mdl-20814387

RESUMO

The marrow contains a variable amount of yellow or fatty marrow and red or cellular marrow creating the signal intensity observed on MRI. Marrow replacement (by cells not normally present in bone marrow) typically is T1W hypointense. Marrow proliferation (by cells normally present in bone marrow) may be T1W hypointense (pseudo marrow replacement) or show intermediate T1W signal intensity due to red marrow redistribution. Marrow edema (reaction to an external process) show intermediate T1W hypointensity (mixture of water and marrow). Location will allow correct diagnosis. Bone marrow ischemia usually results in a necrotic fragment surrounded by a thin T1W hypointense rim.


Assuntos
Doenças da Medula Óssea/diagnóstico , Medula Óssea/patologia , Aumento da Imagem , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Doenças da Coluna Vertebral/diagnóstico , Adenocarcinoma/secundário , Fatores Etários , Idoso , Hematopoese/fisiologia , Humanos , Disco Intervertebral/patologia , Degeneração do Disco Intervertebral/diagnóstico , Masculino , Neoplasias da Próstata/diagnóstico , Valores de Referência , Medula Espinal/patologia , Compressão da Medula Espinal/diagnóstico , Neoplasias da Coluna Vertebral/diagnóstico , Neoplasias da Coluna Vertebral/secundário
14.
Eur Radiol ; 20(11): 2618-27, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20668861

RESUMO

OBJECTIVES: To determine magnetic resonance imaging (MRI) signal and enhancement characteristics of endocrine pancreatic tumours (ETPs) and which MR sequences show them most consistently. METHODS: Fifty-five consecutive patients with 68 ETPs underwent 1.5-T abdominal MRI comprising T2-weighted, unenhanced T1-weighted and dynamic T1-weighted after injection of gadopentetate dimeglumine sequences. Twenty-one patients underwent diffusion-weighted imaging (DWI). Two radiologists identified the number, location, size, signal and enhancement patterns of ETPs, and determined a confidence scale indicating the presence of tumours on DWI. The results were compared with echo-endoscopy (endoscopic ultrasound) findings. RESULTS: The detection sensitivity was 95%, similar to that of echo-endoscopy. T2-weighted and T1-weighted sequences at the arterial phase had the highest contrast-to-noise ratio (CNR) median value. On DWI, the mean sensitivity was 65%. The mean apparent diffusion coefficient (ADC) value of ETP was significantly lower than in the normal parenchyma. CONCLUSION: In suspected ETP, MRI is a sensitive method, similar to echo-endoscopy and could be recommended as the first imaging technique. T2-weighted sequences and T1-weighted sequences in the arterial phase are the optimal pulse sequences. The quantitative assessment of ADC values is a promising tool for the characterisation of pancreatic lesions.


Assuntos
Imageamento por Ressonância Magnética , Neoplasias Pancreáticas/diagnóstico , Adulto , Idoso , Meios de Contraste , Imagem de Difusão por Ressonância Magnética , Endossonografia , Feminino , Gadolínio DTPA , Humanos , Masculino , Pessoa de Meia-Idade , Pâncreas/diagnóstico por imagem , Pâncreas/patologia , Neoplasias Pancreáticas/diagnóstico por imagem , Sensibilidade e Especificidade
15.
Radiat Prot Dosimetry ; 127(1-4): 273-6, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17562653

RESUMO

The aim of this work is to propose an alternative radiochemical procedure for the analysis of U, Pu and Am in urine, which is one of the controls used to monitor workers exposed to risk of internal contamination with actinides. Previous studies have demonstrated the extraction efficiency of these molecules towards uranium and plutonium, the affinity of calix[6]arenes bearing hydroxamic acid groups (LHH3) and carboxylic groups (LCH3) towards americium were studied in this paper by solvent extraction. The results showed that LHH3 and LCH3 have a very good affinity for americium and enhance the possibility of separating Pu from U and Am. Experiments were performed to perfect the separation of U/Am. The immobilisation of these calixarenes on polymer supports was also investigated for routine applications. Supported calixarenes LCH3 and LHH3 presented the same performances as those obtained in a liquid-liquid system and, hence, are a promising system for the analysis of actinides. These molecules and their uses have been protected (patent pending).


Assuntos
Elementos da Série Actinoide/química , Elementos da Série Actinoide/urina , Calixarenos/química , Fracionamento Químico/métodos , Radiometria/métodos , Urinálise/métodos , Misturas Complexas/análise , Misturas Complexas/química , Doses de Radiação
16.
J Clin Microbiol ; 38(2): 656-61, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10655363

RESUMO

A multicenter study was conducted to assess the inter- and intralaboratory reproducibility of the Etest for susceptibility testing of the rapidly growing mycobacteria. The accuracy also was evaluated by comparing Etest results to those obtained by broth microdilution. Ten isolates (four of the Mycobacterium fortuitum group, three of Mycobacterium abscessus, and three of Mycobacterium chelonae) were tested against amikacin, cefoxitin, ciprofloxacin, clarithromycin, doxycycline, imipenem, and trimethoprim-sulfamethoxazole in each of four laboratories. At each site, isolates were tested three times on each of three separate days (nine testing events per isolate) using common lots of media and Etest strips. Interlaboratory agreement among MICs (i.e., mode +/- 1 twofold dilution) varied for the different drug-isolate combinations and overall was best for trimethoprim-sulfamethoxazole (75% for one isolate and 100% for all others), followed by doxycycline and ciprofloxacin. Interlaboratory agreement based on interpretive category also varied and overall was best for doxycycline (100% for all isolates), followed by trimethoprim-sulfamethoxazole and ciprofloxacin. Interlaboratory reproducibility among MICs was most variable for imipenem, and agreement by interpretive category was lowest for imipenem and amikacin. Modal Etest MICs agreed with those by broth microdilution only for doxycycline and the sulfonamides. For all other drugs, the modal MICs by the two methods differed by more than +/- 1 twofold dilution for one or more isolates. In all cases, the Etest MIC was higher and would have caused reports of false resistance. In summary, the Etest in this evaluation did not perform as well as broth microdilution for susceptibility testing of the rapidly growing mycobacteria. It was problematic for most species and drugs, primarily because of a trailing endpoint and/or high MICs compared to broth. Its use will necessitate further investigation, including determination of the optimal medium and incubation conditions and clarification of endpoint interpretation.


Assuntos
Antibacterianos/farmacologia , Mycobacterium chelonae/efeitos dos fármacos , Mycobacterium fortuitum/efeitos dos fármacos , Micobactérias não Tuberculosas/efeitos dos fármacos , Humanos , Laboratórios/normas , Testes de Sensibilidade Microbiana/métodos , Infecções por Mycobacterium não Tuberculosas/microbiologia , Fitas Reagentes , Reprodutibilidade dos Testes
17.
J Clin Microbiol ; 37(6): 1676-82, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10325306

RESUMO

A multicenter study was conducted to assess the interlaboratory reproducibility of broth microdilution testing of the more common rapidly growing pathogenic mycobacteria. Ten isolates (four Mycobacterium fortuitum group, three Mycobacterium abscessus, and three Mycobacterium chelonae isolates) were tested against amikacin, cefoxitin, ciprofloxacin, clarithromycin, doxycycline, imipenem, sulfamethoxazole, and tobramycin (M. chelonae only) in four laboratories. At each site, isolates were tested three times on each of three separate days (nine testing events per isolate) with a common lot of microdilution trays. Agreement among MICs (i.e., mode +/- 1 twofold dilution) varied considerably for the different drug-isolate combinations and overall was best for cefoxitin (91.7 and 97.2% for one isolate each and 100% for all others), followed by doxycycline, amikacin, and ciprofloxacin. Agreement based on the interpretive category, using currently suggested breakpoints, also varied and overall was best for doxycycline (97.2% for one isolate and 100% for the rest), followed by ciprofloxacin and clarithromycin. Reproducibility among MICs and agreement by interpretive category was most variable for imipenem. Based on results reported from the individual sites, it appears that inexperience contributed significantly to the wide range of MICs of several drugs, especially clarithromycin, ciprofloxacin, and sulfamethoxazole. New interpretive guidelines are presented for the testing of M. fortuitum against clarithromycin; M. abscessus and M. chelonae against the aminoglycosides; and all three species against cefoxitin, doxycycline, and imipenem.


Assuntos
Antibacterianos/farmacologia , Testes de Sensibilidade Microbiana/métodos , Mycobacterium chelonae/efeitos dos fármacos , Mycobacterium fortuitum/efeitos dos fármacos , Micobactérias não Tuberculosas/efeitos dos fármacos , Amicacina/farmacologia , Cefoxitina/farmacologia , Ciprofloxacina/farmacologia , Claritromicina/farmacologia , Meios de Cultura , Doxiciclina/farmacologia , Humanos , Imipenem/farmacologia , Infecções por Mycobacterium não Tuberculosas/microbiologia , Mycobacterium chelonae/isolamento & purificação , Mycobacterium fortuitum/isolamento & purificação , Micobactérias não Tuberculosas/isolamento & purificação , Sulfametoxazol/farmacologia , Tobramicina/farmacologia
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