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1.
Ecotoxicol Environ Saf ; 196: 110531, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32244117

RESUMO

The low nitrogen use efficiency (NUE) of fertilizers and aluminum toxicity are major limiting factors for crop development in red soil (acidic soil) of China. Biochar is a promising material for improving soil quality, alleviating aluminum and acidic toxicity. The present study was conducted on maize to evaluate the effects of biochar on NUE and soil quality under different applications of nitrogen fertilizer. Biochar was used in the following five levels in each pot; C0 (0 g), C1 (7.5 g), C2 (15 g), C3 (30 g), C4 (45 g), in combination with δ15N at two N levels: N0 (0 g kg-1) and N1 (0.2 g kg-1). The biochar increased soil nutrients, exchangeable cation, and SOM. Compared with C0, the K+, Ca2+, and Mg2+ were increased by 31.58%, 95.87%, and 463.75% while total Al3+ content of C4 treatment was decreased by 91.98%-93.30% in soil, respectively. X-ray diffraction (XRD) and energy dispersive spectrometer (EDS) showed that Al2SiO5 was adsorbed on the surface of biochar in the soil due to the special physical structure of biochar. Besides, the results showed that root and shoot biomass increased by 44.5% and 89.6%, respectively under biochar treatment. The nitrogen utilization rate of the plant was increased by 11.08% after the amendment of biochar to soil. The δ15N content was increased from 11.97 to 21.32 for root and from 50.84 to 82.33 mg kg-1 for the shoot. The use of biochar with N fertilizer showed a more positive effect on improving NUE of maize and facilitating soil quality. Our results suggest that biochar could be used to improve soil available nutrients, alleviate aluminum toxicity and acidic toxicity. Therefore, biochar could also increase the NUE of maize by adjusting soil quality.


Assuntos
Alumínio/química , Carvão Vegetal/química , Nitrogênio/metabolismo , Solo/química , Zea mays/metabolismo , Alumínio/farmacocinética , Disponibilidade Biológica , Biomassa , Carvão Vegetal/análise , Fertilizantes/análise , Concentração de Íons de Hidrogênio , Nitrogênio/análise , Poluentes do Solo/química , Poluentes do Solo/farmacocinética , Zea mays/crescimento & desenvolvimento
2.
Natl Med J India ; 32(1): 38-40, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31823940

RESUMO

Aluminium utensils are ubiquitous in Indian households and other developing countries. Concerns have recently been raised on the pathological effects of aluminium on the human body, due to its leaching from utensils with long-term use, which has been associated with certain clinical conditions such as anaemia, dementia and osteo-malacia. While some studies suggest that cooking in utensils or aluminium foils is safe, others suggest that it may lead to toxic levels of aluminium in the body. However, studies have shown that leaching of aluminium from cooking utensils depends on many factors such as pH, temperature and cooking medium. In healthy controls, 0.01 %-1 % of orally ingested aluminium is absorbed from the gastrointestinal tract and is eliminated by the kidney. Although the metal has a tendency to accumulate in tissues and may result in their dysfunction, the literature suggests that the apprehension is more apt in patients with chronic renal insufficiency. This article offers solutions to mitigate the risk of aluminium toxicity.


Assuntos
Alumínio/farmacocinética , Utensílios de Alimentação e Culinária/normas , Absorção Intestinal , Indústria Manufatureira/normas , Eliminação Renal , Alumínio/normas , Alumínio/toxicidade , Anemia/induzido quimicamente , Anemia/prevenção & controle , Utensílios de Alimentação e Culinária/legislação & jurisprudência , Demência/induzido quimicamente , Demência/prevenção & controle , Temperatura Alta/efeitos adversos , Humanos , Índia , Indústria Manufatureira/legislação & jurisprudência , Osteomalacia/induzido quimicamente , Osteomalacia/prevenção & controle , Fatores de Tempo
3.
Pediatrics ; 144(6)2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31767714

RESUMO

Aluminum has no known biological function; however, it is a contaminant present in most foods and medications. Aluminum is excreted by the renal system, and patients with renal diseases should avoid aluminum-containing medications. Studies demonstrating long-term toxicity from the aluminum content in parenteral nutrition components led the US Food and Drug Administration to implement rules for these solutions. Large-volume ingredients were required to reduce the aluminum concentration, and small-volume components were required to be labeled with the aluminum concentration. Despite these rules, the total aluminum concentration from some components continues to be above the recommended final concentration. The concerns about toxicity from the aluminum present in infant formulas and antiperspirants have not been substantiated but require more research. Aluminum is one of the most effective adjuvants used in vaccines, and a large number of studies have documented minimal adverse effects from this use. Long-term, high-concentration exposure to aluminum has been linked in meta-analyses with the development of Alzheimer disease.


Assuntos
Alumínio/efeitos adversos , Soluções/química , Adjuvantes Farmacêuticos/química , Alumínio/análise , Alumínio/farmacocinética , Doença de Alzheimer , Antiperspirantes/química , Criança , Soluções para Diálise/química , Contaminação de Medicamentos/legislação & jurisprudência , Rotulagem de Medicamentos/legislação & jurisprudência , Regulamentação Governamental , Humanos , Lactente , Fórmulas Infantis/química , Recém-Nascido , Recém-Nascido Prematuro , Rim/metabolismo , Nefropatias/metabolismo , Nutrição Parenteral , Soluções/normas , Estados Unidos , United States Food and Drug Administration , Vacinas/química
4.
Arch Toxicol ; 93(12): 3503-3521, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31659427

RESUMO

Aluminium is one of the most abundant elements in earth's crust and its manifold uses result in an exposure of the population from many sources. Developmental toxicity, effects on the urinary tract and neurotoxicity are known effects of aluminium and its compounds. Here, we assessed the health risks resulting from total consumer exposure towards aluminium and various aluminium compounds, including contributions from foodstuffs, food additives, food contact materials (FCM), and cosmetic products. For the estimation of aluminium contents in foodstuff, data from the German "Pilot-Total-Diet-Study" were used, which was conducted as part of the European TDS-Exposure project. These were combined with consumption data from the German National Consumption Survey II to yield aluminium exposure via food for adults. It was found that the average weekly aluminium exposure resulting from food intake amounts to approx. 50% of the tolerable weekly intake (TWI) of 1 mg/kg body weight (bw)/week, derived by the European Food Safety Authority (EFSA). For children, data from the French "Infant Total Diet Study" and the "Second French Total Diet Study" were used to estimate aluminium exposure via food. As a result, the TWI can be exhausted or slightly exceeded-particularly for infants who are not exclusively breastfed and young children relying on specially adapted diets (e.g. soy-based, lactose free, hypoallergenic). When taking into account the overall aluminium exposure from foods, cosmetic products (cosmetics), pharmaceuticals and FCM from uncoated aluminium, a significant exceedance of the EFSA-derived TWI and even the PTWI of 2 mg/kg bw/week, derived by the Joint FAO/WHO Expert Committee on Food Additives, may occur. Specifically, high exposure levels were found for adolescents aged 11-14 years. Although exposure data were collected with special regard to the German population, it is also representative for European and comparable to international consumers. From a toxicological point of view, regular exceedance of the lifetime tolerable aluminium intake (TWI/PTWI) is undesirable, since this results in an increased risk for health impairments. Consequently, recommendations on how to reduce overall aluminium exposure are given.


Assuntos
Alumínio/toxicidade , Exposição Ambiental/efeitos adversos , Medição de Risco/métodos , Adolescente , Alumínio/farmacocinética , Animais , Carcinógenos/toxicidade , Criança , Pré-Escolar , Exposição Dietética/efeitos adversos , Exposição Dietética/análise , Exposição Ambiental/análise , Aditivos Alimentares/efeitos adversos , Contaminação de Alimentos/análise , Humanos , Lactente , Mutagênicos/toxicidade , Testes de Toxicidade Aguda
5.
Plant Physiol Biochem ; 137: 93-101, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30771565

RESUMO

Aluminum (Al) toxicity in the acid soils (pH ≤ 5) is the major limiting abiotic factor affecting the productivity of crops. Boron (B) has been reported to alleviate Al toxicity. In spite of recent advances, it is not clear how B relieves Al toxicity. Results demonstrated that Al toxicity hampered the root elongation. Moreover, lumogallion fluorescent molecular probe unequivocally localized mostly bound Al to the periphery of the cell wall (CW) and to the nuclei. Additionally, Al toxicity induced variations in the CW components through the accumulation of pectin and hemicellulose. Nevertheless, B supply reduced callose deposition, increased root growth and reduced changes in the CW components under Al toxicity. Moreover, B supply reduced the un-methylated pectin while increased the degree of methyl esterification of pectin. These results imply that B due to its role in the CW formation could reduce aluminum-induced negative effects on plant growth by attenuating apoplastic Al3+ and changes in the CW components which ultimately results in the improved root growth.


Assuntos
Alumínio/toxicidade , Antioxidantes/metabolismo , Boro/farmacologia , Parede Celular/efeitos dos fármacos , Citrus/efeitos dos fármacos , Alumínio/análise , Alumínio/farmacocinética , Ácido Ascórbico/metabolismo , Boro/farmacocinética , Parede Celular/química , Citrus/citologia , Citrus/metabolismo , Glucanos/metabolismo , Microscopia Confocal , Monoaminoxidase/metabolismo , Células Vegetais/efeitos dos fármacos , Células Vegetais/metabolismo , Folhas de Planta/metabolismo , Proteínas de Plantas/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Análise de Componente Principal , Xantina Oxidase/metabolismo
6.
Arch Toxicol ; 93(1): 37-47, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30302509

RESUMO

Knowledge of dose linearity, plasma clearance, rate and extent of subcutaneous (SC) and intramuscular (IM) absorption of soluble aluminium (Al) citrate is considered a prerequisite for evaluation of toxicokinetic data obtained from SC or IM administration of Al adjuvants in medicinal products. Therefore, total Al plasma kinetics was investigated after SC, IM, and IV administration of single Al doses (36 and 360 µg/kg IM or SC; 30 and 300 µg/kg IV) given as citrate solution in rats. Control groups receiving vehicle (saline) were run in parallel to monitor background plasma Al levels over time resulting from dietary intake. Evaluation of Al plasma profiles was done by both non-compartmental analysis of baseline-corrected data and simultaneous model fitting to the raw data using a population kinetics approach. High and dose-independent total plasma clearance (6.6 mL/min/kg) was observed after IV administration corresponding to 60-82% of normal rat GFR. This supports the previous assumptions that parenterally administered Al citrate is more rapidly cleared from plasma than other Al species (e.g., chloride or lactate). Furthermore, plasma exposure of Al (Cmax and AUC0-inf) increased dose-proportionally at all administration routes. Fast and complete absorption of Al was observed at each dose level after both SC and IM administration (bioavailability estimates: 88 and 110%). Estimates for the first-order absorption rate constant ka correspond to absorption half-lives of 36 min (SC) and ≤ 13 min (IM). There was no increase in tissue Al content (whole bone and brain) after 36 µg/kg IM compared to control rats.


Assuntos
Alumínio/administração & dosagem , Alumínio/farmacocinética , Toxicocinética , Alumínio/toxicidade , Animais , Ácido Cítrico/administração & dosagem , Ácido Cítrico/farmacocinética , Ácido Cítrico/toxicidade , Injeções Intramusculares , Injeções Intravenosas , Injeções Subcutâneas , Masculino , Ratos , Ratos Wistar
7.
Clin Transl Sci ; 11(6): 573-581, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30052317

RESUMO

A clinical pharmacokinetic study was performed in 12 healthy women to evaluate systemic exposure to aluminum following topical application of a representative antiperspirant formulation under real-life use conditions. A simple roll-on formulation containing an extremely rare isotope of aluminum (26 Al) chlorohydrate (ACH) was prepared to commercial specifications. A 26 Al radio-microtracer was used to distinguish dosed aluminum from natural background, using accelerated mass spectroscopy. The 26 Al citrate was administered intravenously (i.v.) to estimate fraction absorbed (Fabs ) following topical delivery. In blood samples after i.v. administration, 26 Al was readily detected (mean area under the curve (AUC) = 1,273 ± 466 hours×fg/mL). Conversely, all blood samples following topical application were below the lower limit of quantitation (LLOQ; 0.12 fg/mL), except two samples (0.13 and 0.14 fg/mL); a maximal AUC was based on LLOQs. The aluminum was above the LLOQ (61 ag/mL) in 31% of urine samples. From the urinary excretion data, a conservative estimated range for dermal Fabs of 0.002-0.06% was calculated, with a mean estimate of 0.0094%.


Assuntos
Alumínio/farmacocinética , Antiperspirantes/efeitos adversos , Radioisótopos/farmacocinética , Absorção Cutânea , Administração Cutânea , Administração Intravenosa , Adulto , Alumínio/administração & dosagem , Alumínio/efeitos adversos , Antiperspirantes/química , Área Sob a Curva , Qualidade de Produtos para o Consumidor , Feminino , Voluntários Saudáveis , Humanos , Parestesia/induzido quimicamente , Parestesia/epidemiologia , Prurido/induzido quimicamente , Prurido/epidemiologia , Radioisótopos/administração & dosagem , Radioisótopos/efeitos adversos , Eliminação Renal , Adulto Jovem
8.
J Bras Nefrol ; 40(2): 201-205, 2018.
Artigo em Inglês, Português | MEDLINE | ID: mdl-29927461

RESUMO

About four decades ago, the relationship between dialysis-dementia and aluminum (Al) began to be established. The restriction of drugs containing Al and improvements on water quality used for dialysis resulted in the clinical disappearance of Al intoxication. However, high prevalence of Al deposition in bone tissue from Brazilian dialysis patients is still being detected. Through the case report of a patient on hemodialysis (HD) for one year, presenting significant Al deposition in bone tissue, we speculated if this problem is not being underestimated. We used extensive investigation to identify potential sources of Al exposure with a careful review of medication history and water quality controls. Al concentration was measured by different methods, including mass spectrometry, in poly-electrolyte concentrate solutions and solution for peritoneal dialysis, in an attempt to elucidate the possible sources of contamination. The objective of this case report is to alert the medical community about a potential high prevalence of Al deposition in bone tissue and to discuss the possible sources of contamination in patients with chronic kidney disease (CKD).


Assuntos
Alumínio/farmacocinética , Osso e Ossos/metabolismo , Insuficiência Renal Crônica/metabolismo , Adulto , Humanos , Masculino , Diálise Peritoneal , Insuficiência Renal Crônica/terapia
9.
Artigo em Inglês | MEDLINE | ID: mdl-29869925

RESUMO

A novel aluminum/olivine composite (AOC) was prepared by wet impregnation followed by calcination and was introduced as an efficient adsorbent for defluoridation. The adsorption of fluoride was modeled with one-, two- and three-parameter isotherm equations by non-linear regression to demonstrate the adsorption equilibrium. The FI was the best-fitted model among the two-parameter isotherms with a R2 value of 0.995. The three-parameter models were found to have better performance with low values of the error functions and high F values. The neural-network-based model was applied for the first time in the isotherm study. The optimized model was framed with eight neurons in hidden layer with a mean square of error of 0.0481 and correlation coefficient greater than 0.999. The neural-based model has the better predictability with a higher F value of 9484 and R2 value of 0.998 compared to regression models, exhibiting the F value and the R2 in the range of 86-3572 and 0.835-0.995, respectively. The material characterization established the formation of the aluminum oxide, silicate, etc. onto the olivine which is conducive of the removal of fluoride by the formation of aluminum fluoride compounds, such as AlF3 in the spent material after defluoridation.


Assuntos
Fluoretos/farmacocinética , Compostos de Ferro/farmacocinética , Compostos de Magnésio/farmacocinética , Redes Neurais de Computação , Silicatos/farmacocinética , Purificação da Água , Absorção Fisico-Química , Alumínio/química , Alumínio/farmacocinética , Óxido de Alumínio/química , Fenômenos Químicos , Fluoretos/química , Compostos de Ferro/química , Cinética , Análise dos Mínimos Quadrados , Compostos de Magnésio/química , Silicatos/química , Temperatura , Purificação da Água/instrumentação , Purificação da Água/métodos
10.
Artigo em Inglês | MEDLINE | ID: mdl-29869939

RESUMO

Spent hydroprocessing catalysts are known to contain a variety of potentially toxic metals and therefore studies on the bioavailability and mobility of these metals are critical for understanding the possible environmental risks of the spent catalysts. This study evaluates the different chemical fractions/forms of aluminium (Al), nickel (Ni), and molybdenum (Mo) in spent hydroprocessing catalyst and the changes they undergo during bioleaching with Acidithiobacillus ferrooxidans. In the spent catalyst (prior to bioleaching), Al was primarily present in its residual form, suggesting its low environmental mobility. However, Ni comprised mainly an exchangeable fraction, indicating its high environmental mobility. Molybdenum was mainly in the oxidizable form (47.1%), which indicated that highly oxidizing conditions were required to liberate it from the spent catalyst. During bioleaching the exchangeable, reducible and oxidizable fractions of all the metals were leached, whereas the residual fractions remained largely unaffected. At the end of bioleaching process, the metals remaining in the bioleached sample were predominantly in the residual fraction (98.3-99.5%). The 'risk assessment code' (RAC) and IR analysis also demonstrated that the environmental risks of the bioleached residue were significantly lower compared to the untreated spent catalyst. The results of this study suggest that bioleaching is an effective method in removing the metals from spent catalysts and the bioleached residue poses little environmental risk.


Assuntos
Acidithiobacillus/metabolismo , Alumínio/isolamento & purificação , Fracionamento Químico/métodos , Molibdênio/isolamento & purificação , Níquel/isolamento & purificação , Alumínio/química , Alumínio/farmacocinética , Biodegradação Ambiental , Catálise , Hidrólise , Metais/química , Metais/isolamento & purificação , Metais/farmacocinética , Molibdênio/química , Molibdênio/farmacocinética , Níquel/química , Níquel/farmacocinética , Indústria de Petróleo e Gás , Oxirredução , Águas Residuárias/química , Poluentes Químicos da Água/química , Poluentes Químicos da Água/isolamento & purificação , Poluentes Químicos da Água/farmacocinética
11.
J. bras. nefrol ; 40(2): 201-205, Apr.-June 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-954535

RESUMO

ABSTRACT About four decades ago, the relationship between dialysis-dementia and aluminum (Al) began to be established. The restriction of drugs containing Al and improvements on water quality used for dialysis resulted in the clinical disappearance of Al intoxication. However, high prevalence of Al deposition in bone tissue from Brazilian dialysis patients is still being detected. Through the case report of a patient on hemodialysis (HD) for one year, presenting significant Al deposition in bone tissue, we speculated if this problem is not being underestimated. We used extensive investigation to identify potential sources of Al exposure with a careful review of medication history and water quality controls. Al concentration was measured by different methods, including mass spectrometry, in poly-electrolyte concentrate solutions and solution for peritoneal dialysis, in an attempt to elucidate the possible sources of contamination. The objective of this case report is to alert the medical community about a potential high prevalence of Al deposition in bone tissue and to discuss the possible sources of contamination in patients with chronic kidney disease (CKD).


RESUMO Cerca de quatro décadas atrás, a relação entre demência relacionada à diálise e alumínio (Al) começou a ser estabelecida. A restrição de medicamentos contendo Al e melhorias na qualidade da água utilizada na diálise resultaram no desaparecimento clínico da intoxicação por Al. Contudo, no Brasil continua a ser identificada uma elevada prevalência de deposição de Al no tecido ósseo de pacientes em diálise. O presente relato de caso de um paciente em hemodiálise (HD) há um ano com deposição significativa de Al no tecido ósseo nos leva a especular se esse problema não tem sido subestimado. Realizamos uma ampla investigação para identificar possíveis fontes de exposição ao Al, com uma revisão cuidadosa do histórico de medicação e dos controles de qualidade da água. A concentração de Al foi medida por diferentes métodos, incluindo espectrometria de massa, nos concentrados polieletrolíticos para hemodiálise e soluções de diálise peritoneal, na tentativa de elucidar as possíveis fontes de contaminação. O objetivo do presente relato de caso é alertar a comunidade médica sobre uma possível elevada prevalência de deposição de Al no tecido ósseo e discutir as possíveis fontes de contaminação nos pacientes com doença renal crônica (DRC).


Assuntos
Humanos , Masculino , Adulto , Osso e Ossos/metabolismo , Insuficiência Renal Crônica/metabolismo , Alumínio/farmacocinética , Diálise Peritoneal , Insuficiência Renal Crônica/terapia
12.
Plant Physiol ; 177(3): 1254-1266, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29784768

RESUMO

Boron (B) alleviates aluminum (Al) toxicity in higher plants; however, the underlying mechanisms behind this phenomenon remain unknown. Here, we used bromocresol green pH indicator, noninvasive microtest, and microelectrode ion flux estimation techniques to demonstrate that B promotes root surface pH gradients in pea (Pisum sativum) roots, leading to alkalization in the root transition zone and acidification in the elongation zone, while Al inhibits these pH gradients. B significantly decreased Al accumulation in the transition zone (∼1.0-2.5 mm from the apex) of lateral roots, thereby alleviating Al-induced inhibition of root elongation. Net indole acetic acid (IAA) efflux detected by an IAA-sensitive platinum microelectrode showed that polar auxin transport, which peaked in the root transition zone, was inhibited by Al toxicity, while it was partially recovered by B. Electrophysiological experiments using the Arabidopsis (Arabidopsis thaliana) auxin transporter mutants (auxin resistant1-7; pin-formed2 [pin2]) and the specific polar auxin transporter inhibitor1-naphthylphthalamic acid showed that PIN2-based polar auxin transport is involved in root surface alkalization in the transition zone. Our results suggest that B promotes polar auxin transport driven by the auxin efflux transporter PIN2 and leads to the downstream regulation of the plasma membrane-H+-ATPase, resulting in elevated root surface pH, which is essential to decrease Al accumulation in this Al-targeted apical root zone. These findings provide a mechanistic explanation for the role of exogenous B in alleviation of Al accumulation and toxicity in plants.


Assuntos
Alumínio/toxicidade , Boro/farmacologia , Ácidos Indolacéticos/metabolismo , Ervilhas/efeitos dos fármacos , Raízes de Plantas/efeitos dos fármacos , Alumínio/farmacocinética , Arabidopsis/efeitos dos fármacos , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Transporte Biológico/efeitos dos fármacos , Membrana Celular/metabolismo , Concentração de Íons de Hidrogênio , Mutação , Ervilhas/metabolismo , Ftalimidas/farmacologia , Proteínas de Plantas/metabolismo , Raízes de Plantas/química , Raízes de Plantas/metabolismo , ATPases Translocadoras de Prótons/metabolismo
13.
Drug Chem Toxicol ; 41(3): 294-301, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29578368

RESUMO

To investigate the effect of pectin on absorption and bio-toxicity of aluminum, pectin extract (100 mg kg-1 d-1) from banana pulp was orally administrated to aluminum exposed mice (35 mg kg-1 d-1) for 6 weeks. Our result showed that body weight gain of the mice treated with aluminum plus banana pectin was 32.5% higher than that of mice exposed to aluminum alone after 6 weeks of the administration. In both the step-down inhibitory avoidance task and Morris water maze test, memory retention of aluminum-exposed mice was significantly improved by the pectin administration. Treatment with banana pectin effectively prevented absorption of aluminum from the gastrointestinal tract, total aluminum excretion of mice treated with banana pectin plus aluminum was 9.3% higher than that of mice exposed to aluminum alone on the 12th day. Aluminum level in serum, cerebrum, or cerebellum of mice treated with aluminum plus banana pectin was 30.8%, 17.5%, or 17.9% lower than that of mice exposed to aluminum alone on the 42nd day, respectively. In conclusion, banana pectin extract can effectively reduce aluminum toxicity in mice.


Assuntos
Alumínio/toxicidade , Disfunção Cognitiva/prevenção & controle , Musa , Fármacos Neuroprotetores/farmacologia , Pectinas/farmacologia , Alumínio/farmacocinética , Animais , Disfunção Cognitiva/induzido quimicamente , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos ICR , Musa/química
14.
Environ Toxicol ; 33(6): 623-630, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29457689

RESUMO

Halloysite (Al2 Si2 O5 (OH)4 ·nH2 O) nanotubes (HNTs) are natural clay materials and widely applied in many fields due to their natural hollow tubular structures. Many in vitro studies indicate that HNTs exhibit a high level of biocompatibility, however the in vivo toxicity of HNTs remains unclear. The objective of this study was to assess the hepatic toxicity of the purified HNTs in mice via oral route. The purified HNTs were orally administered to mice at 5, 50, and 300 mg/kg body weight (BW) every day for 30 days. Oral administration of HNTs stimulated the growth of the mice at the low dose (5 mg/kg BW) with no liver toxicity, but inhibited the growth of the mice at the middle (50 mg/kg BW) and high (300 mg/kg BW) doses. In addition, oral administration of HNTs at the high dose caused Al accumulation in the liver but had no marked effect on the Si content in the organ. The Al accumulation caused significant oxidative stress in the liver, which induced hepatic dysfunction and histopathologic changes. These findings demonstrated that Al accumulation-induced oxidative stress played an important role in the oral HNTs-caused liver injury.


Assuntos
Silicatos de Alumínio/toxicidade , Alumínio/farmacocinética , Fígado/efeitos dos fármacos , Nanotubos/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Administração Oral , Silicatos de Alumínio/administração & dosagem , Silicatos de Alumínio/química , Silicatos de Alumínio/farmacocinética , Animais , Argila , Dano ao DNA/efeitos dos fármacos , Fígado/metabolismo , Masculino , Camundongos , Nanotubos/química , Fatores de Tempo , Testes de Toxicidade Crônica
15.
Ann Pharm Fr ; 75(4): 245-256, 2017 Jul.
Artigo em Francês | MEDLINE | ID: mdl-28576261

RESUMO

We reviewed the three reference toxicokinetic studies commonly used to suggest innocuity of aluminum (Al)-based adjuvants. A single experimental study was carried out using isotopic 26Al (Flarend et al., 1997). This study ignored adjuvant cell capture. It was conducted over a short period of time (28 days) and used only two rabbits per adjuvant. At the endpoint, Al retention was 78% for aluminum phosphate and 94% for aluminum hydroxide, both results being incompatible with quick elimination of vaccine-derived Al in urines. Tissue distribution analysis omitted three important retention sites: the injected muscle, the draining lymph node and bone. Two theoretical studies have evaluated the potential risk of vaccine Al in infants, by reference to the oral Minimal Risk Level (MRL) extrapolated from animal studies. Keith et al., 2002 used a too high MRL (2mg/kg/d), an erroneous model of 100% immediate absorption of vaccine Al, and did not consider renal and blood-brain barrier immaturity. Mitkus et al. (2011) only considered absorbed Al, with erroneous calculations of absorption duration. They ignored particulate Al captured by immune cells, which play a role in systemic diffusion and the neuro-inflammatory potential of the adjuvant. MRL they used was both inappropriate (oral Al vs injected adjuvant) and far too high (1mg/kg/d) with regard to experimental studies of Al-induced memory and behavioral changes. Both paucity and serious weaknesses of these studies strongly suggest that novel experimental studies of Al adjuvants toxicokinetics should be performed on the long-term, including post-natal and adult exposures, to ensure innocuity and restore population confidence in Al-containing vaccines.


Assuntos
Adjuvantes Imunológicos/farmacocinética , Hidróxido de Alumínio/farmacocinética , Alumínio/farmacocinética , Compostos de Alumínio , Animais , Humanos , Fosfatos , Coelhos , Valores de Referência , Distribuição Tecidual , Toxicocinética , Vacinas
16.
PLoS One ; 12(4): e0175398, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28388664

RESUMO

Our previous study found that Lactobacillus plantarum CCFM639 had the ability to alleviate acute aluminum (Al) toxicity when the strain was introduced simultaneously with Al exposure. This research was designed to elucidate the therapeutic effects of living and dead L. plantarum CCFM639 against chronic Al toxicity and to gain insight into the protection modes of this strain. Animals were assigned into control, Al only, Al + living CCFM639, and Al + dead CCFM639 groups. The Al exposure model was established by drinking water for the first 4 weeks. The strain was given after Al exposure by oral gavage at 109 colony-forming units once per day for 12 weeks. The results show that the Al binding ability of dead CCFM639 was similar to that of living CCFM639 in vitro. The ingestion of living or dead CCFM639 has similar effects on levels of Al and trace element in tissues, but living strains led to more significant amelioration of oxidative stress and improvement of memory deficits in Al-exposed mice. In conclusion, in addition to intestinal Al sequestration, CCFM639 treatment offers direct protection against chronic Al toxicity by alleviation of oxidative stress. Therefore, L. plantarum CCFM639 has a potential as dietary supplement ingredient that provides protection against Al-induced injury.


Assuntos
Alumínio/toxicidade , Lesões Encefálicas/prevenção & controle , Lactobacillus plantarum , Fígado/lesões , Alumínio/farmacocinética , Animais , Enzimas/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL
17.
Regul Toxicol Pharmacol ; 88: 310-321, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28237896

RESUMO

As a potentially toxic agent on nervous system and bone, the safety of aluminium exposure from adjuvants in vaccines and subcutaneous immune therapy (SCIT) products has to be continuously re-evaluated, especially regarding concomitant administrations. For this purpose, knowledge on absorption and disposition of aluminium in plasma and tissues is essential. Pharmacokinetic data after vaccination in humans, however, are not available, and for methodological and ethical reasons difficult to obtain. To overcome these limitations, we discuss the possibility of an in vitro-in silico approach combining a toxicokinetic model for aluminium disposition with biorelevant kinetic absorption parameters from adjuvants. We critically review available kinetic aluminium-26 data for model building and, on the basis of a reparameterized toxicokinetic model (Nolte et al., 2001), we identify main modelling gaps. The potential of in vitro dissolution experiments for the prediction of intramuscular absorption kinetics of aluminium after vaccination is explored. It becomes apparent that there is need for detailed in vitro dissolution and in vivo absorption data to establish an in vitro-in vivo correlation (IVIVC) for aluminium adjuvants. We conclude that a combination of new experimental data and further refinement of the Nolte model has the potential to fill a gap in aluminium risk assessment.


Assuntos
Alumínio/farmacocinética , Alumínio/toxicidade , Adjuvantes Imunológicos/farmacocinética , Adjuvantes Imunológicos/toxicidade , Humanos , Toxicocinética , Vacinação
18.
Plant Physiol ; 173(2): 1420-1433, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27932419

RESUMO

Phytohormones such as ethylene and auxin are involved in the regulation of the aluminum (Al)-induced root growth inhibition. Although jasmonate (JA) has been reported to play a crucial role in the regulation of root growth and development in response to environmental stresses through interplay with ethylene and auxin, its role in the regulation of root growth response to Al stress is not yet known. In an attempt to elucidate the role of JA, we found that exogenous application of JA enhanced the Al-induced root growth inhibition. Furthermore, phenotype analysis with mutants defective in either JA biosynthesis or signaling suggests that JA is involved in the regulation of Al-induced root growth inhibition. The expression of the JA receptor CORONATINE INSENSITIVE1 (COI1) and the key JA signaling regulator MYC2 was up-regulated in response to Al stress in the root tips. This process together with COI1-mediated Al-induced root growth inhibition under Al stress was controlled by ethylene but not auxin. Transcriptomic analysis revealed that many responsive genes under Al stress were regulated by JA signaling. The differential responsive of microtubule organization-related genes between the wild-type and coi1-2 mutant is consistent with the changed depolymerization of cortical microtubules in coi1 under Al stress. In addition, ALMT-mediated malate exudation and thus Al exclusion from roots in response to Al stress was also regulated by COI1-mediated JA signaling. Together, this study suggests that root growth inhibition is regulated by COI1-mediated JA signaling independent from auxin signaling and provides novel insights into the phytohormone-mediated root growth inhibition in response to Al stress.


Assuntos
Alumínio/toxicidade , Arabidopsis/efeitos dos fármacos , Ciclopentanos/metabolismo , Oxilipinas/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Alumínio/farmacocinética , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/metabolismo , Ciclopentanos/farmacologia , Etilenos/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Ácidos Indolacéticos/metabolismo , Malatos/metabolismo , Microtúbulos/efeitos dos fármacos , Microtúbulos/metabolismo , Oxilipinas/farmacologia , Reguladores de Crescimento de Planta/metabolismo , Reguladores de Crescimento de Planta/farmacologia , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Plantas Geneticamente Modificadas , Transdução de Sinais/efeitos dos fármacos , Estresse Fisiológico/efeitos dos fármacos
19.
J Biotechnol ; 236: 57-63, 2016 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-27485814

RESUMO

Living and non-living biomass of Pseudomonas putida A (ATCC 12633) was used as biosorbent for the removing of Al(3+) from aqueous solutions. The process was stable with time, efficient at pH 4.3 and between 15°C and 42°C. Two isotherms models were applied to describe the interaction between the biosorbent and Al(3+). Non-living biomass of P. putida A (ATCC 12633) was found to be the most efficient at adsorbing Al(3+) with a maximum sorption capacity of 0.55mg Al(3+)/gr adsorbent and with 36×10(5) binding sites of Al(3+)/microorganisms. Infrared spectroscopy analysis shows that the biosorbent present some vibrational band of functional groups that change in presence of Al(3+): hydroxyl, carboxyl and phosphate. Considering that Al(3+) binds to the phosphate group of phosphatidylcholine, non-viable biomass of P. putida PB01 (mutant lacking phosphatidylcholine) was used. Aluminum adsorption of the parental strain was 30 times higher than values registered in P. putida PB01 (36×10(5) sites/microorganism vs 1.2×10(5) sites/microorganism, respectively). This result evidenced that the absence of phosphatidylcholine significantly affected the availability of the binding sites and consequently the efficiency of the biomass to adsorb Al(3+).


Assuntos
Alumínio/farmacocinética , Pseudomonas putida/metabolismo , Poluentes Químicos da Água/farmacocinética , Adsorção , Alumínio/análise , Biodegradação Ambiental , Biomassa , Concentração de Íons de Hidrogênio , Pseudomonas putida/química , Poluentes Químicos da Água/análise
20.
Sci Rep ; 6: 31578, 2016 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-27515230

RESUMO

Aluminium adjuvants remain the most widely used and effective adjuvants in vaccination and immunotherapy. Herein, the particle size distribution (PSD) of aluminium oxyhydroxide and aluminium hydroxyphosphate adjuvants was elucidated in attempt to correlate these properties with the biological responses observed post vaccination. Heightened solubility and potentially the generation of Al(3+) in the lysosomal environment were positively correlated with an increase in cell mortality in vitro, potentially generating a greater inflammatory response at the site of simulated injection. The cellular uptake of aluminium based adjuvants (ABAs) used in clinically approved vaccinations are compared to a commonly used experimental ABA, in an in vitro THP-1 cell model. Using lumogallion as a direct-fluorescent molecular probe for aluminium, complemented with transmission electron microscopy provides further insight into the morphology of internalised particulates, driven by the physicochemical variations of the ABAs investigated. We demonstrate that not all aluminium adjuvants are equal neither in terms of their physical properties nor their biological reactivity and potential toxicities both at the injection site and beyond. High loading of aluminium oxyhydroxide in the cytoplasm of THP-1 cells without immediate cytotoxicity might predispose this form of aluminium adjuvant to its subsequent transport throughout the body including access to the brain.


Assuntos
Adjuvantes Imunológicos , Hidróxido de Alumínio , Lisossomos/metabolismo , Fosfatos , Vacinação , Adjuvantes Imunológicos/efeitos adversos , Adjuvantes Imunológicos/farmacocinética , Adjuvantes Imunológicos/farmacologia , Alumínio/efeitos adversos , Alumínio/farmacocinética , Alumínio/farmacologia , Hidróxido de Alumínio/efeitos adversos , Hidróxido de Alumínio/farmacocinética , Hidróxido de Alumínio/farmacologia , Morte Celular/efeitos dos fármacos , Humanos , Lisossomos/patologia , Tamanho da Partícula , Fosfatos/efeitos adversos , Fosfatos/farmacocinética , Fosfatos/farmacologia , Células THP-1
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