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Recycling americium alone from the spent fuel is an important issue currently studied for the future nuclear cycle (Generation IV systems) as Am is one of the main contributors to the long-term radiotoxicity and heat power of final waste. The solvent extraction process called EXAm has been developed by the CEA to enable the recovery of Am alone from a PUREX raffinate (with U, Np and Pu already removed). A mixture of DMDOHEMA and HDEHP diluted in TPH is used as the solvent and the Am/Cm selectivity is improved using TEDGA as a selective complexing agent to maintain Cm and the heavier lanthanides in the acidic aqueous phase (HNO 3 5-6 M). Americium is then selectively stripped from the light lanthanides at low acidity (pH 2.5-3) with a polyaminocarboxylic acid (DTPA). An additional step is necessary before Am recovery, in order to strip molybdenum which would otherwise be complexed by DTPA and contaminate the Am raffinate. In order to make the process and its associated future plant more compact, the objective is now to adapt the EXAm process to a concentrated raffinate. With a concentrated PUREX raffinate, the process operates under conditions close to saturation both for the solvent and complexing agent TEDGA during the Am extraction step. Consequently, some changes were needed to adapt the flowsheet to higher concentrations of cations. Before the test on a real PUREX raffinate in the CBP shielded line at ATALANTE (at the end of 2015), the EXAm flowsheet had to be consolidated and achievable target performances ensured. A series of experiments and tests was performed: on laboratory scale (batch experiments), to identify the good operating conditions and to simulate the main phenomena involved (2010-2014); first on an inactive surrogate feed solution at G1 facility (2011 – 2013), and then on a surrogate feed solution with trace amounts of americium and curium (spiked test) in the C17 shielded line at ATALANTE (2014). [ABSTRACT FROM AUTHOR]

It is important to know the mechanisms for forage development, especially those related to the tolerance of potentially toxic elements, when considering their use in phytoremediation in heavy metal contaminated areas. In this study, we evaluated plant growth, concentration, and the availability of cadmium (Cd) for forage grasses (Panicum maximum Jacq. cv. Aruana and cv. Tanzânia; Brachiaria decumbens cv. Basilisk; Brachiaria brizantha cv. Xaraés and cv. Marandu) cultivated in Cd contaminated soils. The experiments were performed under greenhouse conditions over a 90-day evaluation period, and the Cd rates were 2, 4, and 12 mg/kg of soil. The relative growth rate of the forage grasses decreased as Cd rates increased, and the following descending order of susceptibility was observed: Marandu > Xaraés > Aruana > Tanzânia > Basilisk, with regard to phytotoxicity in these plants. The forage Cd concentration increased in line with increases in the Cd rates. Cd contents extracted by Mehlich-1 and by diethylenetriaminepentaacetic acid presented high positive correlation with forage relative growth. The forage plants did not block Cd entry into the food chain because they were not capable of limiting Cd absorption. [ABSTRACT FROM AUTHOR]

Despite effective infant immunization against pertussis, the disease continues to circulate due to waning immunity. Booster vaccinations against pertussis beyond infancy are widely recommended. In Vietnam, however, no recommendations for pertussis boosters beyond the second year of life exist. This open-label, single-centre study was designed to assess the safety of a single booster dose of reduced-antigen-content-diphtheria-tetanus-acellular-pertussis vaccine (dTpa) in 300 healthy Vietnamese children (mean age 7.9 years), who had completed primary vaccination against diphtheria, tetanus and pertussis. Solicited symptoms were recorded for 4 days and unsolicited and serious adverse events (SAEs) for 31 days post-vaccination. Pain and fatigue were the most common solicited local and general symptoms in 35.0% and 14.0% of children, respectively. Grade 3 swelling occurred in 3 children; no large injection site reactions or SAEs were reported. The dTpa booster vaccine was well tolerated and this study supports its administration in school age Vietnamese children. [ABSTRACT FROM AUTHOR]

Monoclonal antibodies (mAb) are being widely studied for the treatment of cancers and other diseases. The mAb is typically in a solution formulation and administered as an intravenous infusion. Ready-to-use solutions are favored for their clinical convenience but they can potentially suffer from a shorter shelf life due to accelerated rates of some forms of degradation such as oxidation, relative to lyophilized formulations. To improve stability, the chelating agent diethylene triamine pentaacetic acid (DTPA) is often used at very low concentrations in biologics formulations to prevent oxidation induced by metal ions. Because of its low concentration and susceptibility to changes in concentration during stability study or processing, the measurement of DTPA levels during formulation and process development is critical. In response to this need we developed a platform reversed-phase HPLC method that allows for the rapid and direct determination of DPTA concentrations which does not require the prior removal of mAbs in formulation samples. The method exploits the “size exclusion effect” of C18 columns with narrow pore sizes (90–120 Å) to elute large mAb at the void volume, enabling direct injections of mAb samples for quantitation of DTPA. The method was found to be suitable for the analysis of DTPA in the range of 2–20 μg/mL across multiple drug formulations containing different therapeutic mAb and antibody drug conjugates. The method was successfully validated for specificity, precision, accuracy, linearity, and robustness. [ABSTRACT FROM AUTHOR]

The influence of some complexing agents of (poly)aminopolycarboxylic acids (diethylenetriaminopentaacetic acid (DTPA), ethylenediaminotetraacetic acid (EDTA), nitrilotriacetic acid (NTA), and iminodiacetic acid (IDA)) on the sorption of Cu by crystal and amorphous (hydr)oxides of Fe(III), Al(III), and Mn(IV) that are widespread mineral components of soils was studied. The obtained results are considered in terms of complex-formation in the solution and on the sorbent's surface. The effect of the complexing agents on the metal sorption (mobilization/immobilization) is determined by (1) the stability, structure, and sorption capability of compexonates formed in the solution; (2) the acidity, and (3) the nature of the sorbent. The desorption effect on Cu cations was found to change in the following sequence of complexing agents: EDTA > DTPA ≫ NTA > IDA. The high-dentate complexing agents (EDTA, DTPA) had the greatest impact on ?u cations bound with crystalline (hydr)oxides of Fe, Al, and Mn. The low denticity of the complexing agents (IDA, NTA) and binding of ?u with amorphous sorbents leads to the weakening of desorption. The decrease in acidity promoted the mobilization of the metal under the influence of complexing agents; the increase in acidity caused its immobilization. The growth in the mobility of heavy metals bound with soil (hydr)oxides of Fe, Al, and Mn due to the complexing agents entering the surface and ground water is considered a factor of ecological risk. [ABSTRACT FROM AUTHOR]

Ion-pairing high-performance liquid chromatography–ultraviolet (HPLC–UV) methods were developed to determine two commonly used chelating agents, ethylenediaminetetraacetic acid (EDTA) in Abilify® (a small molecule drug with aripiprazole as the active pharmaceutical ingredient) oral solution and diethylenetriaminepentaacetic acid (DTPA) in Yervoy® (a monoclonal antibody drug with ipilimumab as the active pharmaceutical ingredient) intravenous formulation. Since the analytes, EDTA and DTPA, do not contain chromophores, transition metal ions (Cu 2+ , Fe 3+ ) which generate highly stable metallocomplexes with the chelating agents were added into the sample preparation to enhance UV detection. The use of metallocomplexes with ion-pairing chromatography provides the ability to achieve the desired sensitivity and selectivity in the development of the method. Specifically, the sample preparation involving metallocomplex formation allowed sensitive UV detection. Copper was utilized for the determination of EDTA and iron was utilized for the determination of DTPA. In the case of EDTA, a gradient mobile phase separated the components of the formulation from the analyte. In the method for DTPA, the active drug substance, ipilimumab, was eluted in the void. In addition, the optimization of the concentration of the ion-pairing reagent was discussed as a means of enhancing the retention of the aminopolycarboxylic acids (APCAs) including EDTA and DTPA and the specificity of the method. The analytical method development was designed based on the chromatographic properties of the analytes, the nature of the sample matrix and the intended purpose of the method. Validation data were presented for the two methods. Finally, both methods were successfully utilized in determining the fate of the chelates. [ABSTRACT FROM AUTHOR]

This study was carried out with the objective of evaluating the effect of citrate concentration on the extraction efficiency of some micronutrients from soil. Composite surface soil samples (0–20 cm) were collected from Eastern Harage Zone (Babile and Haramaya Districts), Wolaita Zone (Damot Sore, Boloso Bombe, Damot Pulasa and Humbo Districts) and Dire Dawa Administrative Council in purposive sampling. The treatments were arranged in completely randomized design (CRD) with three replications. A greenhouse pot experiment with soybean plant was conducted to determine the correlation between soil test methods and the selected micronutrients, such as iron (Fe), copper (Cu), manganese (Mn) and zinc (Zn) in the leaves of the plant. The results showed that, among the different citrate concentrations with strontium chloride (SrCl2) tested for the determination of available Fe, Mn and Zn, the highest correlation coefficients (r = 0.82,p < 0.05), (r = 0.96,p < 0.001) and (r = 0.98,p < 0.001) were found between the diethylenetriamine pentaacetic acid (DTPA) method and 0.02 M strontium chloride (SrCl2)-0.025 M citric acid extractant, respectively. Therefore, 0.02 M SrCl2-0.025 M citric acid extractant is considered to be the most effective for the determination of Fe, Mn and Zn in soils of the studied areas. Similarly, high correlation coefficients (r = 0.97,p < 0.001) were found between DTPA and 0.02 M SrCl2-0.05 M citric acid and (r = 0.88,p < 0.01) between DTPA and 0.02 M SrCl2-0.025 M citric acid extractants for the determination of available Cu from soils. Hence, the 0.02 M SrCl2-0.05 M citric acid extractant was shown to be the best for the determination of Cu in soils of the studied areas. However, considering the use of universal extractant, the 0.02 M SrCl2-0.025 M citric acid extractant could easily be adopted as a procedure for the determination of Fe, Cu, Mn and Zn for both agricultural and environmental purposes. The greenhouse experiment confirmed the result. [ABSTRACT FROM AUTHOR]

The study was conducted to elucidate the effect of three levels of compost amended soils (0, 3, and 6%, w/w) on Cd, Cu, and Zn extractability and uptake by radish plant (Raphanus sativus) grown in calcareous and sandy soils contaminated with 0, 40, 80 or 160 mg metal kg-1 soil. DTPA extraction and greenhouse experiments were designed. The study revealed that the addition of compost treatments improved the plant biomass in both uncontaminated/contaminated two soils since the dry weight of shoots and roots for the two compost treatments was higher than that of the control (0 compost addition) even in high contamination level. Also, For Cu and Zn, the plants cultivated in metals levels (40-160 mg kg-1) showed a significant increase in the dry weight in both radish shoots and roots grown in the both soils; whereas increase Cd levels from 40 to 160 mg kg-1 decreased the dry weight of both radish shoots and roots. DTPA extractable Cd and Cu in addition to their concentrations in radish shoots/roots grown in the soils were decreased as a result of compost amendments with more pronounced at high compost level; whereas the opposite results were obtained for Zn. Good correlations were obtained in most cases between DTPA extractable metals and absorbed by radish plant indicated by correlation coefficients. These findings highlight the applicable of compost to ameliorate Cd and Cu risks in high contaminated soils. [ABSTRACT FROM AUTHOR]

Agricultural recycling of sewage sludge has been a source of accumulation of heavy metals in the environment which may reach toxic levels and cause serious damage to the biota. Field experiments were undertaken for two agricultural years (2000 and 2002) and effects of two sewage sludge applications were evaluated through the extraction of (essential and non-essential) transition metals by diethylenetriaminepentaacetic acid (DTPA) extractor in a medium texture dystrophic Dark Red Latosol. Cd, Ni, Co, Pb and Cr were not detected. Application of sewage sludge initially caused a slight pH rise in the soil; later pH lowered and kept itself close to the starting level. It could be concluded that through consecutive sludge application, extractable rates of Fe and Mn in soil samples gradually increased during the two agricultural years in proportion to sewage sludge doses and sampling period. In fact, they were higher than rates of control. Due to low concentrations of soil samples, extractor had a restricted capacity for evaluation of its phytoavailability.A reciclagem agrícola do lodo de esgoto tem provocado o acúmulo de metais pesados no solo e na água, podendo atingir níveis tóxicos e causar danos às plantas cultivadas, aos animais e ao homem, por meio da cadeia trófica. Neste intuito foi desenvolvido o presente experimento, em condições de campo, entre 2000 e 2002, onde foram avaliados os efeitos da aplicação de lodo de esgoto por dois anos, sobre a extração de metais de transição (essenciais e não) pelo extrator DTPA em um Latossolo Vermelho distrófico (LVd) de textura média. As concentrações dos elementos metálicos: Mn, Fe, Cd, Ni, Co, Pb e Cr não foram detectados pelo método da absorção atômica na solução obtida com o extrator DTPA. A aplicação de lodo de esgoto causou inicialmente pequena elevação no pH do solo, posteriormente a diminuição do mesmo, e manteve-se próximo ao original. Foi possível concluir que, com a aplicação consecutiva do lodo, os teores extraíveis de Fe e Mn nas amostras de solos aumentaram gradativamente nos dois anos agrícolas, com as doses do lodo de esgoto aplicado, época de amostragens, e foram superiores ao tratamento testemunha. O extrator apresentou capacidade restrita para avaliação da fitodisponibilidade dos metais pesados decorrentes das baixas concentrações nas amostras de solo.

For the purpose to develop novel Tc-labeled tumor imaging agents with SPECT, colchicine (CHC) was directly labeled by Tc using diethylene triamine pentacetate acid (DTPA) as bifunctional chelating agent. Trimethylcolchicinic acid, derivatived from colchicine, was conjugated to DTPA to get the new ligand DTPA-CHC, which was labeled by Tc in the presence of SnCl as reducing agent. The radiochemical purity of the Tc-DTPA-CHC complex was over 90 %. It had good hydrophilicity and was stable at room temperature. The high initial tumor uptake with moderate retention, good tumor/muscle ratios and satisfactory scintigraphic images highlighted the potential of Tc-DTPA-CHC for tumor imaging. [ABSTRACT FROM AUTHOR]

A avaliação do método modificado da resina de troca de íons para extração de Mn e Fe dos solos foi o objetivo desta pesquisa. Foram utilizadas 44 amostras de solo, cujos teores de Mn variaram de baixos a altos e de Fe de médios a altos. Como plantas-teste, utilizaram-se o milho e a soja, cultivadas em casa de vegetação. O Fe e o Mn do solo foram determinados, usando o método modificado da resina de troca de íons, DTPA, AB-DTPA, Mehlich-1 e Mehlich-3. Os coeficientes de correlação entre Mn no solo e Mn acumulado na parte aérea da soja foram: resina (0,62*), DTPA (0,58*), Mehlich-3 (0,54*), Mehlich-1 (0,51*) e AB-DTPA (0,26NS). Para o milho, houve correlação entre Mn-solo e Mn-planta somente nas amostras de solo com baixos teores desse elemento, para todos os extratores, exceto para AB-DTPA. Concluiu-se que a resina foi tão eficiente quanto os extratores DTPA, M-1 e M-3 em avaliar a disponibilidade de Mn para a soja, e que nenhum extrator foi eficiente em avaliar a disponibilidade de Fe para as plantas de milho e soja, com 53 dias de idade, cultivadas em casa de vegetação.The objective of this research was to evaluate a modified ion exchange resin method for Mn and Fe extraction from soils. Forty-four soil samples presenting low, medium, and high Mn and medium to high Fe concentrations were used. Maize and soybeans plants were grown as test plants in a pot experiment in a greenhouse. Soil samples were analyzed for Mn and Fe using the modified ion exchange resin, DTPA, AB-DTPA, Mehlich-1, and Mehlich-3 methods. The correlation coefficients between soil Mn and Mn accumulated in the soybean shoot were: ion exchange resin (0.62*), DTPA (0.57*), Mehlich-3 (0.54*), Mehlich-1 (0.51*), and AB-DTPA (0.26). For maize, significant correlation coefficients between soil Mn and plant-Mn were obtained only when low-initial Mn soil samples were considered for all extractants, except for AB-DTPA. For soybeans, the modified ion exchange resin method was as efficient as DTPA, Mehlich-1 and Mehlich-3 for the evaluation of soil Mn availability. None of the methods was efficient for evaluating the soil Fe availability for the 53 day-old maize and soybean plants grown in greenhouse.

Contents of heavy metal on agricultural soils have been raised by land applications of sewage sludge and may constitute a hazard to plants, animals and humans. A field experiment was carried out from 1983 to 1987, to evaluate the long-term effect of sewage sludge application, with and without liming, on heavy metal accumulation and availability in a Rhodic Hapludox soil grown with maize (HMD 7974 hybrid). Trials were set up in a completely randomized blocks design with four replications. Each block was split in two bands, one with and another without liming. The sludge was applied in each band at rates: 0, 20, 40, 60 and 80 Mg ha-1 (dry basis) in a single application; and 40, 60 and 80 Mg ha-1 split in two, three and four equal yearly applications, respectively. The soil was sampled for chemical analysis each year after harvest. Soil samples were analysed for Cu, Ni and Zn in extracts obtained with DTPA and Mehlich-3 solutions, and in extracts obtained by digestion with nitric-perchloric acid (total metal contents), using an inductively coupled plasma (ICP) spectrometer. In general, Zn, Cu and Ni concentrations in DTPA and Mehlich-3 extracts increased linearly with sludge application. Total Cu and Zn concentrations increased when sludge was applied, whereas total Ni concentrations were not affected. Both extractants were suitable to evaluate Cu and Zn availability to corn in the soil treated with sewage sludge. Liming reduced the DTPA extractability of Zn. DTPA-extractable Cu concentrations were not significantly affected by liming. Mehlich-3-extractable Cu and Zn concentrations increased with liming. Only DTPA extractant indicated reduction of Ni concentrations in the soil after liming.

A presença de metais pesados em compostos de lixo urbano é um dos principais motivos da insegurança de sua utilização agronômica. Desta forma, foram avaliados os efeitos da aplicação sucessiva do composto de lixo sobre os teores de Cd, Cr, Cu, Ni, Pb e Zn em um Latossolo Amarelo distrófico, em plantas de cana-de-açúcar, e a fitodisponibilidade desses metais medida pelos extratores DTPA, HCl 0,1 mol L-1 e Mehlich-3. Experimento de campo foi realizado nos anos agrícolas 1996/97 e 1997/98, sendo o composto aplicado nas doses de 0, 20, 40 e 60 Mg ha-1 e de 0, 24, 48 e 72 Mg ha-1, respectivamente. A aplicação consecutiva do composto aumentou os teores totais de Cu do solo que variaram, em relação à testemunha, de 12 a 25 %, no primeiro ano agrícola, e de 27 a 88 %, no segundo ano agrícola. Para Zn, esses valores variaram de 12 a 72 % e de 72 a 156 %, no primeiro e no segundo ano, respectivamente, e de Cr de 12 a 25 %, no segundo ano. Os teores totais de Cd, Ni e Pb, no solo, e de Cd, Cr, Ni e Pb, nas folhas, colmos e caldo das plantas, mantiveram-se abaixo do limite de determinação. Os teores de Cu e Zn nas amostras de plantas não aumentaram. Os extratores químicos praticamente não diferiram entre si e apresentaram capacidades restritas para a avaliação da fitodisponibilidade dos metais pesados decorrente das baixas concentrações nas amostras de solo e planta.

OBJETIVO: Ação do ácido trissódio-cálcio-dietileno-triaminopentaacético (CaNa3DTPA), quelante de ferro com ação ainda anti-viral, antiinflamatória e imunológica, na atenuação de lesões de reperfusão em músculos esqueléticos de ratos. MÉTODOS: 52 ratos Wistar, pesando 188±22g, foram anestesiados e submetidos a semi-amputação de membro posterior direito (MPD), poupando-se o fêmur, artéria e veia femorais. Foram então randomizados e distribuídos: G1-CTAN - controle anestesia, sem cirurgia e sem isquemia; G2-CTCIR - controle cirurgia, sem isquemia; G3-IRCT e G3-IRDTPA - com isquemia (4 hora) e reperfusão ( 2 horas). O G3-IRCT foi tratado, ao final da isquemia, com cloreto de sódio 0,9% e G3-IRDTPA com (CaNa3DTPA).Parâmetros: Circunferência do pé direito e peso do rato, dosagem sérica de CPK, dosagem de malonaldeído e microscopia óptica de músculos soleus bilateral. RESULTADOS: Aumento da circunferência nos G3-IRCT e G3-IRDTPA (significante no G3-IRCT quando comparado ao G1-CTAN); CPK elevado nos G3-IRCT e G3-IRDTPA comparados aos controles; MDA mais alto no membro contralateral do G3-IRDTPA, comparado ao MPD do G3-IRDTPA e ao G1-CTAN; maior edema intersticial em G3-IRCT, maior infiltrado inflamatório em G3-IRDTPA e recuperação dos níveis de glicogênio semelhantes em G3-IRCT e G3-IRDTPA. CONCLUSÃO: Apesar do menor edema no G3-IRDTPA comparado ao G3-IRCT, o CaNa3DTPA não alterou CPK sérico, MDA muscular e morfologia muscular dos animais.

Diante dos riscos ambientais relacionados ao uso agrícola de lodo de esgoto contendo metais foi realizado um experimento, com o objetivo de avaliar o efeito do lodo, combinado ou não com P, K e PK, sobre o acúmulo de metais na parte aérea das plantas e comparar a eficiência de extratores na fitodisponibilidade de metais. Amostras da camada de 0-20 cm de um Argissolo Vermelho Amarelo eutrófico foram transferidas para vasos e tratadas com doses equivalentes a 0, 10, 20, 30, 40 e 50 Mg ha-1 de lodo (base seca). Após 30 dias de incubação, determinou-se os teores de Fe, Mn, Cu, Zn, Cd, Ni, Cr e Pb (extraídos por HCl 0,1 mol L-1, Mehlich-3 e DTPA pH 7,3), procedeu-se aplicação de duas doses de P (0 e 100 mg kg-1) e duas dose de K (0 e 100 mg kg-1). Cultivaram-se plantas de milho (Zea mays L.) durante 50 dias, coletando-se a parte aérea para determinação de metais. A aplicação de lodo aumentou o teor de Fe, Mn, Zn e Cu no solo e o acúmulo pelas plantas, enquanto a complementação do resíduo com potássio aumentou a produção de matéria seca e diminuiu o acúmulo de Zn. A redução do pH e o Mn nativo do solo influenciaram no aumento da disponibilidade Mn. Todos os extratores foram eficientes para predição da fitodisponibilidade de Zn e Cu. Para o Mn e Fe, os mais eficientes foram: HCl e Mehlich-3, HCl e DTPA, respectivamente. Para os demais metais, os extratores se mostraram pouco eficientes.

Sol-gel technology is a versatile tool for preparation of complex silica-based materials with targeting functions for use as adsorbents in water purification. Most efficient removal of organic pollutants is achieved by using enzymatic reagents grafted on nano-carriers. However, enzymes are easily deactivated in the presence of heavy metal cations. In this work, we avoided inactivation of immobilized urease by Cu (II) and Cd (II) ions using magnetic nanoparticles provided with additional complexonate (diethylene triamine pentaacetic acid or DTPA) functions. Obtained nanomaterials were characterized by Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), and scanning electron microscopy (SEM). According to TGA, the obtained Fe3O4/SiO2-NH2-DTPA nanoadsorbents contained up to 0.401 mmol/g of DTPA groups. In the concentration range Ceq = 0–50 mmol/L, maximum adsorption capacities towards Cu (II) and Cd (II) ions were 1.1 mmol/g and 1.7 mmol/g, respectively. Langmuir adsorption model fits experimental data in concentration range Ceq = 0–10 mmol/L. The adsorption mechanisms have been evaluated for both of cations. Crosslinking of 5 wt % of immobilized urease with glutaraldehyde prevented the loss of the enzyme in repeated use of the adsorbent and improved the stability of the enzymatic function leading to unchanged activity in at least 18 cycles. Crosslinking of 10 wt % urease on the surface of the particles allowed a decrease in urea concentration in 20 mmol/L model solutions to 2 mmol/L in up to 10 consequent decomposition cycles. Due to the presence of DTPA groups, Cu2+ ions in concentration 1 µmol/L did not significantly affect the urease activity. Obtained magnetic Fe3O4/SiO2-NH2-DTPA-Urease nanocomposite sorbents revealed a high potential for urease decomposition, even in presence of heavy metal ions.

The effects of ethylenediaminetetraacetic acid (EDTA) and diethylene triaminepentaacetic acid (DTPA) on cadmium (Cd) uptake by water hyacinth (Eichhornia crassipes) in Cd-contaminated soil was studied. Experimental samples were separated into 4 treatment groups: 1) Untreated control, 2) EDTA addition, 3) DTPA addition, and 4) mixture of EDTA and DTPA (1:1) addition. The plants were harvested at 20, 40, 60, 80 and 100 days. Cd levels were measured in soil samples, water samples and two parts of the plant: shoot (stem and leaves) and root. The results showed that Cd accumulation in plants with added EDTA and DTPA were higher than the control set, indicating that EDTA and DTPA addition increased Cd uptake by water hyacinth. Cd accumulations in the root in all groups were significantly (p < 0.05) higher than that in the shoot. In EDTA added sets, Cd accumulation in the root was higher than in shoots and were measured at 160.91 and 13.37 mg kg-1 at 100 d, respectively. This research indicates that DTPA was most suitable for increasing the cadmium removal capacity of water hyacinth and offers a suitable phytoremediation technique to help clean contaminated sites.

Procedimentos baseados em alterações nas propriedades químicas podem atuar como agentes mitigadores da fitotoxidez de metais pesados no solo. No entanto, é difícil predizer os efeitos de diferentes materiais sobre a disponibilidade de metais em solo contaminado simultaneamente por vários metais. O presente estudo, desenvolvido em solo proveniente de área de rejeitos de uma unidade de extração e industrialização de zinco da Companhia Mineira de Metais-CMM, em Três Marias (MG), objetivou avaliar os teores, a distribuição entre diferentes frações e a biodisponibilidade de Zn, Cd, Cu e Pb nesse solo, após incubação por seis meses com diferentes doses de carbonato, gesso, vermicomposto, serragem e Solomax. Após a incubação, retiraram-se amostras de cada tratamento para análises químicas de fracionamento de metais e extrações simples com DTPA e com Mehlich-1 e repicaram-se plântulas de Mimosa caesalpiniaefolia Benth. (sabiá) para o solo onde cresceram por 90 dias. Os tratamentos causaram alterações nas principais formas dos elementos no solo. Para o Zn, que apresenta os maiores teores nesse solo, houve efeito da aplicação de carbonato, que reduziu a fração trocável de 842 mg kg-1, no controle, para 32 mg kg-1. Houve também uma redução do Zn-trocável com a aplicação de Solomax. Os teores de Zn na parte aérea das plantas reduziram-se de 544,85 mg kg-1, no controle, para 32,20 mg kg-1 com a aplicação de carbonato. O Solomax reduziu em 87% o teor deste elemento nas plantas. Os demais materiais não exerceram efeitos consistentes sobre os teores dos metais na planta. A adição de materiais orgânicos aumentou o teor de Cu e de Pb na fração orgânica e residual, sem efeito na biodisponibilidade. O gesso aumentou a biodisponibilidade dos metais estudados, com exceção do Pb. Ao contrário do que foi verificado para os outros elementos, os teores de Cd na planta correlacionaram-se com as quantidades deste extraídas por DTPA (0,82**) e por Mehlich-1 (0,60**), e os de Zn com MgCl2 (0,49*) e DTPA (0,49*). As extrações seqüencial e simples, com DTPA e Mehlich-1, evidenciaram efeitos diferenciados dos materiais sobre os metais no solo. O Cd foi o elemento com melhor previsão de biodisponibilidade pelos extratores utilizados. O emprego de carbonato foi o tratamento mais eficaz em reduzir a disponibilidade dos metais para M. caesalpiniaefolia.

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The Mehlich 3 method for the extraction of available micronutrients, such as copper (Cu), iron (Fe), manganese (Mn), and zinc (Zn), is more advantageous compared to the diethylene triamine pentaacetic acid (DTPA) method, because it can also be used for the extraction of macronutrients. The aim of this study was to compare the Mehlich 3 and DTPA methods for 172 soils in Greece having different levels of pH and calcium carbonate. Single and multiple regression analyses were employed to evaluate the relationship between Mehlich 3 and DTPA tests. Mehlich 3 results correlated well with DTPA-extractable Cu and Zn, but the correlation was poor for DTPA-extractable Mn. Also, a high correlation was found between Mehlich 3 and DTPA-extractable Fe for calcareous soils (R2 = 0.89), while a moderate relationship was found for noncalcareous soils (R2 = 0.65), which was improved to 0.78 when the pH was taken into account in multiple regression analysis. [ABSTRACT FROM PUBLISHER]

Background: The current glomerular filtration rate (GFR) equation (CKiD) may be less accurate in adolescents and children with higher GFR. Methods: This was a retrospective study ( n = 161, 247 mTc DTPA-GFRs). Six equations were evaluated for bias, accuracy, and low GFR diagnosis: (1) CKiD; (2) historic center; (3) Hoste(age); (4) Hoste(height); (5) modified Pottel; (6) Gao. Children with ≥ vs. <90 ml/min/1.73 m) and < vs. ≥16 years were compared. Two adult equations were evaluated in children ≥16 years. Results: Most equations underestimated GFR by 1-14 % in the higher GFR group, least so for Hoste(age). In the low GFR group, Hoste(age) and historic center overestimated GFR significantly more than CKiD ( p < 0.05). Accuracy (within 30 % GFR) was similar across equations and GFR subgroups (66-86 %). In the ≥16 years group, CKiD underestimated GFR by ∼10 %, vs. ∼3 % for Hoste(height). Accuracy was 5-10 % lower in the older group and most equations were more sensitive than specific for detecting low GFR; this discrepancy was less for the Hoste equations. Adult equations were highly inaccurate. Conclusions: GFR estimation in older children and with higher GFR is suboptimal. The Hoste(height) may be an alternative GFR estimation method; Hoste(age) may allow for height-independent GFR estimation in patients with normal GFR. [ABSTRACT FROM AUTHOR]

Ion-exchange resins through EDTA or DTPA moieties are synthesized and evaluated for the co-extraction of Cs+and Sr2+radionuclides for wastewater treatment. EDTA-bis(amide) and DTPA-bis(amide) derivatives bearing phenol or catechol moieties obtained from tyramine or dopamine, respectively, were used as building blocks to prepare ion-exchange resins. Their synthesis involved the condensation of formaldehyde with various phenolic rings, catechol (C), resorcinol (R), or calixresorcinarene (CR) under alkaline conditions. The resulting formo-phenolic-like resins have both ion-exchange and chelating groups in their structure and are indeed efficient in the remediation of Cs+and Sr2+, even in salted aqueous solutions. [ABSTRACT FROM PUBLISHER]

Land application of sewage sludge (SS) is a convenient way of disposal compared to incineration or landfill, but can result in accumulation of potentially toxic elements (PTE) in agricultural soils. The environmental risk associated with PTE accumulation in soils that received several SS applications depends mainly on soil pH and SS treatments. We studied the effects of addition to soil of SS treated and untreated with FeCl 3 on the biological availability of Zn, Ni, Cd and Cu to oilseed rape ( Brassica napus ). The plants were grown on an acid and a neutral soil in a greenhouse incubation experiment. The following treatments were carried out: (i) unamended control soil, (ii) sewage sludge amended soils kept bare throughout the experiment and (iii) sewage sludge amended soil planted with oilseed rape. Amended soils received either untreated SS or FeCl 3 treated SS at a rate equivalent to 75 t d.w. ha −1 y −1 . Plant growth was enhanced by addition of both untreated SS and FeCl 3 treated SS, but the latter produced a lower shoot dry matter than untreated SS, particularly in the acid soil. Evaluation of biological availability of PTE was performed by three different methods: plant shoot analysis, single DTPA-extraction, and sequential fractionation procedure (SEP) in soil. After 50 days, accumulation of PTE was considerably larger in plant shoots grown on the acid soil and amended with FeCl 3 treated sludge. Conversely, the FeCl 3 treated SS reduced Cd, Ni and Zn accumulation in shoots in the neutral soil in comparison to untreated SS. Copper was generally unaffected by SS treatment in both soils. Plants significantly decreased the DTPA-extractability of Cd, Ni and Zn in both soils that received FeCl 3 treated SS, but they did not change it in soils that received untreated SS. These different behaviors may be explained by the different mechanism involved in metals stabilization in the two soils: adsorption on Fe and Mn oxides in the neutral soil, precipitation and organic complexation in the acid soil. The chemical flocculation treatment of waste water with FeCl 3 and addition to soils reduces PTE availability in neutral soils amended with SS, but markedly increases their solubility and bio-availability in acid soils. Therefore, the application of SS obtained from flocculation with FeCl 3 should be restricted to neutral or calcareous soils. [ABSTRACT FROM AUTHOR]

The penta ethyl ester of diethylenetriamine pentaacetic acid (DTPA) can be used as a prodrug for decorporation of radionuclides in the event of an internal radiation incidents with transuranic elements. A C18 chromatography purification method was successfully developed using a step elution profile to isolate 0.5-3 g of the four ethyl esters of DTPA. Less than 11 % of the isolated di-ethyl and tri-ethyl esters of DTPA, and less than 20 % of the tetra-ethyl ester of DTPA, had degraded in phosphate buffered saline over a 168 h period. [ABSTRACT FROM AUTHOR]

Purpose: Currently two injectable products of diethylenetriaminepentaacetic acid (DTPA) are U.S. Food and Drug Administration (FDA)-approved for decorporation of 241Am; however, an oral product is considered more amenable in a mass casualty situation. The di-ethyl ester of DTPA, named C2E2, is being developed as an oral drug for treatment of internal radionuclide contamination. Materials and methods: Single-dose decorporation efficacy of C2E2 administered 24-h post contamination was determined in beagle dogs using a 241Am nitrate inhalation contamination model. Single and multiple dose toxicity studies in beagle dogs were performed as part of an initial safety assessment program. In addition, the genotoxic potential of C2E2 was evaluated by the in vitro bacterial reverse mutation Ames test, mammalian cell chromosome aberration cytogenetic assay and an in vivo micronucleus test. Results: Oral administration of C2E2 significantly increased 241Am elimination over untreated controls and significantly reduced the retention of 241Am in tissues, especially liver, kidney, lung and bone. Daily dosing of 200 mg/kg/day for 10 days was well tolerated in dogs. C2E2 was found to be neither mutagenic or clastogenic. Conclusions: The di-ethyl ester of DTPA (C2E2) was shown to effectively enhance the elimination of 241Am after oral administration in a dog inhalation-contamination model and was well tolerated in toxicity studies. [ABSTRACT FROM AUTHOR]

A series of hybrid TiO 2 nanoparticles containing chelating molecules based on diethylenetriaminepentaacetic acid (DTPA) moiety have been synthesized and thoroughly characterized by TEM, SEM, powder XRD, FT-IR, 13 C solid-state MAS NMR, CHN elemental analysis, and BET. The surface modification of these nano-materials was established by coupling accessible amino group functions of TiO 2 /PABA supports ( para -amino benzoic acid, PABA) with either modified-monoanhydride or -carboxylic acid compounds. The extraction percentages, distribution coefficients ( K d Gd ), capacities ( C Gd ) and ionic selectivities ( S Gd/La ) of these surface-functionalized nano-structured materials between lanthanum and gadolinium in acidic range of pH were investigated. [ABSTRACT FROM AUTHOR]

The article reports a study which examines the international and national lacunae in drug advertisements. The researchers seek the opinion of both physicians and patients regarding direct to consumer advertisement (DTCA) and direct to physician advertisement as part of marketing strategies for drug companies. The study recommends more stringent regulations in drug development and suggests that both the physicians and patients should be cautious on drug promotions.

Application of sewage sludge (SS) in agriculture is an alternative technique of disposing this waste. But unreasonable application of SS leads to excessive accumulation of heavy metals in soils. A column experiment was conducted to test the availability of heavy metals to Lolium perenne grown in SS-treated soils following diethylene triamine penta acetic acid (DTPA) application at rates of 0, 10 and 20 mmol kg soil. In order to prevent metal leaching in DTPA-assisted phytoextraction process, a horizontal permeable barrier was placed below the treated soil, and its effectiveness was also assessed. Results showed that DTPA addition significantly increased metal uptake by L. perenne shoots and metal leaching. Permeable barriers increased metal concentrations in plant shoots and effectively decreased metal leaching from the treated soil. Heavy metals in SS-treated soils could be gradually removed by harvesting L. perenne many times in 1 year and adding low dosage of DTPA days before each harvest. [ABSTRACT FROM AUTHOR]

The researches Tc recovery process at presence of divalent Sn(II) were made to determine necessary and sufficient amount of Sn(II), which would provide its full reducibleness in the reaction mixture. That the solution of Tc eluate reacts directly with the solution of modified DTPA and SnCl the content of radiochemical impurity (RCI) of the unreduced Tc(VII) in the labeled nanocolloid is 2.7 %, while the yield of the nanocolloid with the size of 100 nm is approximately 80 %. The results of researches prove the nanocolloid actively gets into the lymphatic system after injection, thus indicating its functional usefulness. [ABSTRACT FROM AUTHOR]

Optically active and racemic Bn-DTPA analogues were evaluated for potential decorporation of radioactive lanthanides. Complexation kinetics of the Bn-DTPA analogues with Sr(II), Ce(III), and Ce(IV) was measured using arsenazo III-based spectroscopic method. The Bn-DTPA analogues effectively and rapidly bound to Sr(II), Ce(III), and Ce(IV). Bn-DTPA was orally administered to mice and evaluated for decorporation of Sr and compared to that of the clinically available Ca(II)-DTPA. (rac)-Bn-DTPA removed Sr in mice more efficiently than DTPA. The Bn-DTPA analogues are promising decorporation agents for potential removal of Sr, Ce, and Ce. [ABSTRACT FROM AUTHOR]

In this study, radiolabeling of a bisphosphonate, alendronate (Alendronate sodium), was performed with the help of a bifunctional chelating agent. For that purpose, DTPA-NHS (Diethylenetriaminepentaacetic acid dianhydride-N-hydroxysuccinimide) was synthesized with an esterification between DTPA and NHS. Combining the DTPA-NHS ester with alendronate yields the DTPA-Alendronate compound. The structure of synthesized compound was analyzed by ¹H/13C/31P-NMR and HPLC. After then, the labeling with [99mTc(CO)3]+ core of synthesized compound was provided. Performing quality controls of newly synthesized [99mTc(CO)3- DTPA-Alendronate] complex with thin layer radiochromatography (TLRC) and high-performance liquid radiochromatography (HPLRC), the labeling yield was found as 99%. It was observed that the compound conserves its stability for 24 h in serum media. Biodistribution of the radiolabeled complex was performed on Wistar Albino rats to determine radiopharmaceutical potential of the [99mTc(CO)3-DTPA-Alendronate] complex. It is thought that the data gained from this study will contribute to the development of complexes with bisphosphonate. [ABSTRACT FROM AUTHOR]

In this study, radiolabeling of a bisphosphonate, alendronate (Alendronate sodium), was performed with the help of a bifunctional chelating agent. For that purpose, DTPA-NHS (Diethylenetriaminepentaacetic acid dianhydride-N-hydroxysuccinimide) was synthesized with an esterification between DTPA and NHS. Combining the DTPA-NHS ester with alendronate yields the DTPA-Alendronate compound. The structure of synthesized compound was analyzed by ¹H/13C/31P-NMR and HPLC. After then, the labeling with [99mTc(CO)3]+ core of synthesized compound was provided. Performing quality controls of newly synthesized [99mTc(CO)3- DTPA-Alendronate] complex with thin layer radiochromatography (TLRC) and high-performance liquid radiochromatography (HPLRC), the labeling yield was found as 99%. It was observed that the compound conserves its stability for 24 h in serum media. Biodistribution of the radiolabeled complex was performed on Wistar Albino rats to determine radiopharmaceutical potential of the [99mTc(CO)3-DTPA-Alendronate] complex. It is thought that the data gained from this study will contribute to the development of complexes with bisphosphonate. [ABSTRACT FROM AUTHOR]

We evaluated and compared a new bombesin analog [Tyr–Gly 5 , Nle 14 ]-BBN(6–14) conjugated to DOTA or DTPA and radiolabeled with In-111 in low and high GRPR expressing tumor models. Both peptides were radiolabeled with high radiochemical purity and specific activity. In vitro assays on T-47D, LNCaP and PC-3 cells showed that the affinity of peptides is similar and a higher binding and internalization of DOTA-peptide to PC-3 cells was observed. Both peptides could target PC-3 and LNCaP tumors in vivo and both tumor types could be visualized by microSPECT/CT. [ABSTRACT FROM AUTHOR]

The primary factor that influences release of zinc (Zn) for plants is the rhizosphere. However, information about Zn-desorption characteristics in the rhizosphere is limited. A greenhouse experiment was performed to determine Zn-release characteristics in the bulk and the rhizosphere soils using a rhizobox. The kinetics of Zn release was determined by successive extraction with diethylenetriaminepentaacetic acid (DTPA)– triethanolamine (TEA) in a period of 1 to 504 h at 25 ± 1 °C in the bulk and the rhizosphere soils. Moreover, Zn extracted by using three extractants [DTPA-TEA, ammonium bicarbonate (AB)-DTPA, and Mehlich 3] in the bulk and the rhizosphere soils. The results showed that Zn extracted in the rhizosphere soils were significantly (P < 0.01) lower than the bulk soils. The mean of Zn release in the bulk and the rhizosphere soils were 5.31 and 4.91 mg kg−1, respectively. Release kinetics of Zn conformed fairly well to power function, first order, parabolic diffusion, and simplified Elovich equations. The results of kinetics study indicated that release-rate coefficients decreased in the rhizosphere soils compare to the bulk soils. The correlation studies showed that Zn release after 504 h was significantly correlated (P < 0.05) with Zn extracted by using DTPA-TEA, AB-DTPA, and Mehlich 3 in the bulk and the rhizosphere soils. The results of this research showed that Zn-release characteristics in the bean rhizosphere soils were different from the bulk soils. [ABSTRACT FROM AUTHOR]