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1.
Anal Bioanal Chem ; 376(4): 542-8, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12739101

RESUMO

A reversed-phase high-performance liquid chromatographic method with fluorescence detection for the determination of labile monomeric aluminium has been developed through pre-column complexation using morin as the analytical reagent. The highly fluorescent aluminium-morin complex (excitation wavelength 418 nm, emission wavelength 490 nm) was separated on a Spherisorb ODS 2 column with an eluent consisting of 30% methanol and 70% water (pH 1.0 with perchloric acid). The most remarkable point of this protocol was that only the most toxic aluminium species, that is, free aqua-aluminium ion and its monomeric hydroxo complex ions, selectively respond among various aluminium complexes. This strategy has been successfully applied to direct fractionation of the toxic aluminium in natural waters and biological samples without any pretreatment.


Assuntos
Alumínio/isolamento & purificação , Flavonoides/química , Poluentes Químicos da Água/isolamento & purificação , Alumínio/sangue , Alumínio/líquido cefalorraquidiano , Alumínio/urina , Cromatografia Líquida de Alta Pressão , Fluorescência , Água Doce/análise , Humanos , Indicadores e Reagentes/química , Sensibilidade e Especificidade , Chá/química , Poluentes Químicos da Água/sangue , Poluentes Químicos da Água/líquido cefalorraquidiano , Poluentes Químicos da Água/urina
2.
J Inorg Biochem ; 87(1-2): 105-13, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11709219

RESUMO

It was demonstrated that the decrease of the differential pulse voltammetric (DPV) anodic peak current of dopamine (3,4-dihydroxyphenylethylamine, DA) was linear with the increase of aluminum (Al) concentration. Under optimum experimental conditions (pH 4.6, 1.2 x 10(-3) M DA, and 0.04 M NaAc-HAc buffer solution), the linear range is 4.0 x 10(-7)-8.0 x 10(-5) M, the detection limit is 1.4 x 10(-7) M, and the relative standard deviation for 4 x 10(-5) M Al(III) is 3.5% (n=8). Many foreign species, especially some low-molecule-weight biological molecules, were chosen for interference testing. The proposed method was applied to the determination of Al in biological samples such as synthetic renal dialysate, Ringer's solution, human blood, cerebrospinal fluid of a patient, and urine of a diabetic patient. The corresponding recoveries were generally between 95 and 105%. The basic principle of the method was determined by examining Al complexed with DA. This results in the blockage of the electroactive sites on DA, followed eventually by the reduction of the electrochemical response of DA. This result was verified by examining the behavior of DA, both in the presence and absence of Al, using electrochemical, UV-Vis, Raman, and (13)C NMR spectroscopic methods.


Assuntos
Alumínio/análise , Dopamina/química , Eletroquímica/métodos , Abastecimento de Água/análise , Alumínio/sangue , Alumínio/líquido cefalorraquidiano , Alumínio/urina , Líquido Ascítico/química , Calibragem , Diabetes Mellitus/urina , Soluções para Diálise/química , Eletrodos , Água Doce/química , Humanos , Concentração de Íons de Hidrogênio , Soluções Isotônicas/química , Espectroscopia de Ressonância Magnética , Solução de Ringer , Sensibilidade e Especificidade , Espectrofotometria Ultravioleta , Análise Espectral Raman
4.
Nephrol Dial Transplant ; 12(8): 1692-8, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9269651

RESUMO

BACKGROUND: The association between aluminium and dialysis encephalopathy and deterioration of the neurological state during desferrioxamine treatment of dialysis patients is well established. At present little is known about the speciation and the mechanisms underlying the element's neurotoxicity. METHODS: Aluminium speciation was performed in cerebrospinal fluid samples of acutely aluminium-intoxicated dialysis patients using a recently developed high-performance liquid chromatographic/electrothermal atomic absorption spectrometric hybrid method. RESULTS: Baseline cerebrospinal fluid aluminium levels of samples taken shortly after the intoxication were low but elevated (5.0 +/- 2.0 micrograms/l, n = 3) as compared to subjects with normal renal function (< 1 microgram/l). In contrast to the situation noted in serum and to the iron speciation in cerebrospinal fluid, aluminium was not bound to transferrin but appeared as two distinct compounds, the main fraction eluting at the elution volume of aluminium-citrate/silicate. The second compound was not identified. Forty-four hours after desferrioxamine administration the cerebrospinal fluid aluminium levels had increased up to a concentration of 10.3 +/- 2.5 micrograms/l (n = 3). This was accompanied by a change in the speciation profile with aluminium appearing at the elution volume of aluminoxamine. CONCLUSIONS: Our findings may contribute to a better understanding of the neurotoxic effects of aluminium and its desferrioxamine chelate in dialysis patients.


Assuntos
Alumínio/líquido cefalorraquidiano , Alumínio/intoxicação , Desferroxamina/uso terapêutico , Diálise Renal , Adulto , Ácido Cítrico/líquido cefalorraquidiano , Desferroxamina/líquido cefalorraquidiano , Feminino , Humanos , Rim/fisiologia , Masculino , Pessoa de Meia-Idade , Compostos Organometálicos/líquido cefalorraquidiano , Valores de Referência , Transferrina/líquido cefalorraquidiano , Transferrina/metabolismo
5.
J Neuroradiol ; 23(3): 168-72, 1996 Dec.
Artigo em Francês | MEDLINE | ID: mdl-9091610

RESUMO

Two patients underwent acoustic schwannoma surgery by transmastoid approach. Petrous bone defect was filled in with aluminium-containing bone cement (Ionocem). A pseudomeningocele by CSF accumulation in subcutaneous temporoparietal area appeared after the procedure and, in subsequent weeks, encephalopathy with confusion and seizures. MRI showed cerebral involvement with herpes-like disposition. Temporal stereotactic biopsy in a case did not confirm viral encephalitis but disclosed cellular accumulation of lipofucsin and particles highly suggestive of aluminum-inclusions. Aluminium's levels in blood and CSF of both patients were very high and confirm the brain's toxic involvement. Aluminium's toxicity would be advocated in patients with neurologic disorders who have undergone maxillofacial or skull bone-cementoplasty by an aluminum-containing biomaterial, if this cement is in contact with CSF.


Assuntos
Silicatos de Alumínio/efeitos adversos , Alumínio/efeitos adversos , Materiais Biocompatíveis/efeitos adversos , Cimentos Ósseos/efeitos adversos , Cimentos de Ionômeros de Vidro/efeitos adversos , Sistema Límbico/efeitos dos fármacos , Imageamento por Ressonância Magnética , Idoso , Alumínio/sangue , Alumínio/líquido cefalorraquidiano , Silicatos de Alumínio/sangue , Silicatos de Alumínio/líquido cefalorraquidiano , Encefalopatias/induzido quimicamente , Encefalopatias/patologia , Confusão/induzido quimicamente , Diagnóstico Diferencial , Encefalite Viral/diagnóstico , Feminino , Humanos , Sistema Límbico/patologia , Lipofuscina/análise , Masculino , Meningocele/líquido cefalorraquidiano , Meningocele/etiologia , Pessoa de Meia-Idade , Neuroma Acústico/cirurgia , Osso Petroso/cirurgia , Convulsões/induzido quimicamente
6.
J Gastroenterol Hepatol ; 11(10): 911-5, 1996 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8912126

RESUMO

To investigate the possible absorption and deposition of bismuth or aluminium from agents used in the treatment of peptic ulcers, we have measured levels of bismuth and aluminium in the liver tissue of 15 patients undergoing elective liver biopsy and in the cerebrospinal fluid (CSF) of 15 patients undergoing elective myelography after administration of standard therapeutic doses of tripotassium dicitrato bismuthate (TBS), sucralfate or aluminium hydroxide for 1 month. Aliquots of liver or CSF were separated and levels of both aluminium and bismuth were assayed in each sample by atomic absorption spectrophotometry. The group who received TBS had significantly higher liver bismuth levels than the other two treatment groups, but there was no significant difference in CSF bismuth levels among the three groups. There was no significant difference in either liver or CSF aluminium levels among the three treatment groups. We conclude that tissue accumulation of bismuth may occur after short-course therapy with colloidal bismuth, although there is no evidence of CNS accumulation of bismuth in the present study.


Assuntos
Alumínio/farmacocinética , Antiulcerosos/farmacocinética , Bismuto/farmacocinética , Fígado/metabolismo , Alumínio/líquido cefalorraquidiano , Hidróxido de Alumínio/farmacocinética , Hidróxido de Alumínio/uso terapêutico , Antiulcerosos/uso terapêutico , Biópsia , Bismuto/líquido cefalorraquidiano , Feminino , Humanos , Fígado/patologia , Masculino , Pessoa de Meia-Idade , Mielografia , Compostos Organometálicos/farmacocinética , Compostos Organometálicos/uso terapêutico , Sucralfato/farmacocinética , Sucralfato/uso terapêutico , Fatores de Tempo
8.
Presse Med ; 24(10): 489-90, 1995 Mar 11.
Artigo em Francês | MEDLINE | ID: mdl-7746806

RESUMO

A great deal of research has focused on aluminium as a putative causative factor in Alzheimer's disease. We measured by atomic absorption spectrophotometry aluminium levels in blood, urine and cerebrospinal fluid from 15 patients with Alzheimer's disease, compared with 20 control individuals. There were no statistically significant differences between the two groups. This suggests that aluminium is not a causative factor for Alzheimer's disease.


Assuntos
Alumínio/sangue , Doença de Alzheimer/sangue , Idoso , Alumínio/efeitos adversos , Alumínio/líquido cefalorraquidiano , Alumínio/urina , Doença de Alzheimer/líquido cefalorraquidiano , Doença de Alzheimer/induzido quimicamente , Doença de Alzheimer/urina , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valores de Referência , Fatores de Risco
12.
Toxicol Lett ; 63(1): 7-12, 1992 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1412525

RESUMO

Aluminum causes central nervous system (CNS) toxicities in both humans and various animal species. Although blood aluminum concentrations are monitored in the clinic, very little is known regarding the relationship between such concentrations and corresponding CNS aluminum content. As a first step in that direction, this study was undertaken to simultaneously determine blood and CSF kinetics of this element. Following intravenous injection of aluminum (1 mg/kg), there was a rapid (within 30 min, post injection) increase in CSF aluminum; peak concentrations (38-45 ng/ml) were achieved between 2-3 h. While peak blood aluminum concentrations increased about 58-fold from the pre-dose value (from 256 +/- 120 to 14,730 +/- 388 ng/ml), corresponding increases in CSF aluminum were only about 20-fold. Blood and CSF aluminum concentrations declined monoexponentially with half-lives of 2.77 and 3.45 h, respectively (P < 0.05). Results from these showed that blood and CSF compartments achieve equilibrium and indicated the feasibility of determining brain aluminum content using blood concentrations.


Assuntos
Alumínio/farmacocinética , Alumínio/sangue , Alumínio/líquido cefalorraquidiano , Animais , Barreira Hematoencefálica/efeitos dos fármacos , Meia-Vida , Injeções Intravenosas , Masculino , Ratos , Ratos Sprague-Dawley , Espectrofotometria Atômica
13.
Mol Chem Neuropathol ; 17(1): 79-89, 1992 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-1388451

RESUMO

In the present study the acute effect of intravenous aluminum chloride (1 mg/kg) on choline acetyltransferase (ChAT) and acetylcholinesterase (AChE) activities of rats was investigated. Aluminum was found to cross the blood-brain barrier (BBB) as indicated by the detection of aluminum in the cerebrospinal fluid (CSF) 30 min after femoral vein injection. Two hours following aluminum injection, ChAT activity in the basal forebrain and hippocampus was significantly reduced by 30% and 22%, respectively, whereas no change was observed in the caudate nuclei. On the other hand, AChE activity was significantly increased by 45% in the caudate nuclei, whereas little change was observed in other brain areas. This report demonstrates that rapid transport of Al across the BBB, and the acute nature of Al neurotoxicity in rats.


Assuntos
Alumínio/toxicidade , Doenças do Sistema Nervoso Autônomo/induzido quimicamente , Sistema Nervoso Parassimpático , Acetilcolinesterase/metabolismo , Adenilil Ciclases/metabolismo , Alumínio/líquido cefalorraquidiano , Animais , Doenças do Sistema Nervoso Autônomo/líquido cefalorraquidiano , Doenças do Sistema Nervoso Autônomo/patologia , Colina O-Acetiltransferase/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Ratos , Ratos Sprague-Dawley , Espectrofotometria Atômica
14.
J Clin Lab Anal ; 6(5): 264-8, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1403346

RESUMO

Detailed procedures were developed for the furnace atomic absorption spectrophotometry (FAAS) determination of aluminum (Al) in serum, urine, cerebrospinal fluid (CSF), and proportionated dialysate. Of particular note were the use of Mg (NO3)2.6H2O as a matrix modifier and the employment of the standard additions routine in analysis. The accuracy of the method(s) used is supported by work with assayed controls and by recovery studies. The use of a "clean room" was shown to be unnecessary. Normal serum, urine, and CSF Al ranges observed were 4.8-8.9, 5.1-9.1, and 1.0-5.8 micrograms L-1 respectively.


Assuntos
Alumínio/sangue , Espectrofotometria Atômica/métodos , Alumínio/líquido cefalorraquidiano , Alumínio/urina , Ambiente Controlado , Estudos de Avaliação como Assunto , Humanos , Espectrofotometria Atômica/estatística & dados numéricos
15.
Am J Kidney Dis ; 16(2): 157-9, 1990 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-2382654

RESUMO

Deferoxamine is widely used in the diagnosis and treatment of aluminum toxicity and has a characteristic combination of side effects, including a poorly defined worsening of existing neurologic symptoms. However, to date, no measurement of cerebrospinal fluid (CSF) aluminum concentrations after deferoxamine exist. We report the case of a patient who developed acute neurological deterioration in conjunction with sepsis and elevated serum aluminum levels shortly after renal transplantation. Simultaneous values for blood and CSF aluminum were measured in response to deferoxamine and hemodialysis. The increase in CSF aluminum levels appears to parallel that seen in serum after deferoxamine. We hypothesize that this elevation in CSF aluminum may account for the observed neurologic deterioration after deferoxamine and postulate various pathophysiologic mechanisms that might be involved.


Assuntos
Alumínio/líquido cefalorraquidiano , Encefalopatias/induzido quimicamente , Desferroxamina/efeitos adversos , Falência Renal Crônica/terapia , Diálise Renal/efeitos adversos , Adulto , Alumínio/efeitos adversos , Encefalopatias/tratamento farmacológico , Desferroxamina/uso terapêutico , Feminino , Humanos , Transplante de Rim
16.
Indian J Med Res ; 92: 9-12, 1990 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2347614

RESUMO

In an attempt to ascertain the role of aluminium in sporadic motor neuron disease (MND), trace metals were estimated in blood, plasma and cerebrospinal fluid (CSF) of 38 patients of sporadic MND and 30 controls by direct current plasma emission spectrophotometry. CSF aluminium levels (20.76 +/- 4.38 micrograms/dl) were significantly higher (P less than 0.05) in those patients of MND who presented as progressive bulbar palsy (PBP) as compared to the other subtypes of MND (amyotrophic lateral sclerosis = 7.71 +/- 2.01 micrograms/dl; progressive muscular atrophy = 10.01 +/- 2.41 micrograms/dl) and controls (11.63 +/- 2.82 micrograms/dl). Aluminium may be important in the etiopathogenesis of a subgroup of sporadic MND.


Assuntos
Alumínio/líquido cefalorraquidiano , Neurônios Motores , Doenças Neuromusculares/líquido cefalorraquidiano , Adolescente , Adulto , Idoso , Alumínio/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doenças Neuromusculares/sangue
17.
Artigo em Alemão | MEDLINE | ID: mdl-3961019

RESUMO

Some selected CSF and serum components were determined in demental patients classified by the Hachinski test into vascular and primary-degenerative groups. As for the vascular group, the frequency distribution of the serum/CSF albumin ratios characterizing the barrier function corresponds to that of controls, in primary-degenerative cases, however, it is shifted to higher values. In vascular dementia higher CSF LAP activities pointing to actual cell damaging processes in the CNS were found. The concentrations of lactate and some trace metals in CSF and serum are not suitable for differential diagnostic purposes.


Assuntos
Barreira Hematoencefálica , Demência/líquido cefalorraquidiano , Idoso , Alumínio/líquido cefalorraquidiano , Cobalto/líquido cefalorraquidiano , Cobre/líquido cefalorraquidiano , Humanos , Lactatos/líquido cefalorraquidiano , Ácido Láctico , Leucil Aminopeptidase/líquido cefalorraquidiano , Albumina Sérica/líquido cefalorraquidiano , Zinco/líquido cefalorraquidiano
19.
Ann Neurol ; 5(6): 580-1, 1979 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-475352

RESUMO

Spinal fluid from 180 male patients was examined for aluminum levels. Values were coordinated for age and protein determinations. In addition, values were listed according to the patient's diagnosis. Although in most instances no correlation could be made, 10 patients with Alzheimer disease showed significantly low levels of aluminum.


Assuntos
Alumínio/líquido cefalorraquidiano , Doença de Alzheimer/líquido cefalorraquidiano , Demência/líquido cefalorraquidiano , Adulto , Fatores Etários , Idoso , Humanos , Masculino , Pessoa de Meia-Idade
20.
Ann Biol Clin (Paris) ; 36(1): 33-8, 1978.
Artigo em Francês | MEDLINE | ID: mdl-686518

RESUMO

The possibilities of use of a graphite oven type HGA 74 (Perkin Elmer) for the estimation of aluminium in biological fluids by atomic absorption spectrophotometry are described, with a special study of the stages of drying, mineralisation, atomisation, flow of inert gas, requirement for correction of non-specific absorption, etc. Under fixed experimental conditions, the limit of sensitivity (absorption 1%) was 2.28.10.(-11) grams and the linearity was good up to 100 microgram/l. This method of analysis by direct treatment of the samples required only small volumes of the latter and reduces the risk of contamination.


Assuntos
Alumínio/análise , Líquidos Corporais/análise , Espectrofotometria Atômica/métodos , Alumínio/sangue , Alumínio/líquido cefalorraquidiano , Alumínio/urina , Estudos de Avaliação como Assunto
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