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1.
J Trace Elem Med Biol ; 27(4): 257-66, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23870171

RESUMO

The aetiology of breast cancer is multifactorial. While there are known genetic predispositions to the disease it is probable that environmental factors are also involved. Recent research has demonstrated a regionally specific distribution of aluminium in breast tissue mastectomies while other work has suggested mechanisms whereby breast tissue aluminium might contribute towards the aetiology of breast cancer. We have looked to develop microwave digestion combined with a new form of graphite furnace atomic absorption spectrometry as a precise, accurate and reproducible method for the measurement of aluminium in breast tissue biopsies. We have used this method to test the thesis that there is a regional distribution of aluminium across the breast in women with breast cancer. Microwave digestion of whole breast tissue samples resulted in clear homogenous digests perfectly suitable for the determination of aluminium by graphite furnace atomic absorption spectrometry. The instrument detection limit for the method was 0.48 µg/L. Method blanks were used to estimate background levels of contamination of 14.80 µg/L. The mean concentration of aluminium across all tissues was 0.39 µg Al/g tissue dry wt. There were no statistically significant regionally specific differences in the content of aluminium. We have developed a robust method for the precise and accurate measurement of aluminium in human breast tissue. There are very few such data currently available in the scientific literature and they will add substantially to our understanding of any putative role of aluminium in breast cancer. While we did not observe any statistically significant differences in aluminium content across the breast it has to be emphasised that herein we measured whole breast tissue and not defatted tissue where such a distribution was previously noted. We are very confident that the method developed herein could now be used to provide accurate and reproducible data on the aluminium content in defatted tissue and oil from such tissues and thereby contribute towards our knowledge on aluminium and any role in breast cancer.


Assuntos
Alumínio/análise , Neoplasias da Mama/química , Biópsia , Neoplasias da Mama/diagnóstico , Feminino , Humanos , Micro-Ondas , Espectrofotometria Atômica/instrumentação
2.
J Alzheimers Dis ; 33(2): 423-30, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-22976072

RESUMO

There has been a plausible link between human exposure to aluminum and Alzheimer's disease for several decades. We contend that the only direct and ethically acceptable experimental test of the 'aluminum hypothesis', which would provide unequivocal data specific to the link, is to test the null hypothesis that a reduction in the body burden of aluminum to its lowest practical limit would have no influence upon the incidence, progression, or severity of Alzheimer's disease. Herein we are testing the hypothesis that silicon-rich mineral waters can be used as non-invasive methods to reduce the body burden of aluminum in individuals with Alzheimer's disease and a control group consisting of their carers and partners. We have shown that drinking up to 1 L of a silicon-rich mineral water each day for 12 weeks facilitated the removal of aluminum via the urine in both patient and control groups without any concomitant affect upon the urinary excretion of the essential metals, iron and copper. We have provided preliminary evidence that over 12 weeks of silicon-rich mineral water therapy the body burden of aluminum fell in individuals with Alzheimer's disease and, concomitantly, cognitive performance showed clinically relevant improvements in at least 3 out of 15 individuals. This is a first step in a much needed rigorous test of the 'aluminum hypothesis of Alzheimer's disease' and a longer term study involving many more individuals is now warranted.


Assuntos
Alumínio/toxicidade , Doença de Alzheimer , Águas Minerais/administração & dosagem , Silício/administração & dosagem , Idoso , Alumínio/farmacocinética , Alumínio/urina , Doença de Alzheimer/epidemiologia , Doença de Alzheimer/etiologia , Doença de Alzheimer/terapia , Cognição/fisiologia , Cobre/urina , Feminino , Humanos , Incidência , Ferro/urina , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Ácido Silícico/administração & dosagem , Resultado do Tratamento , Abastecimento de Água
3.
J Alzheimers Dis ; 31(4): 725-730, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22699848

RESUMO

The deposition in the brain of amyloid-ß as beta sheet conformers associated with senile plaques and vasculature is frequently observed in Alzheimer's disease. While metals, primarily aluminum, iron, zinc, and copper, have been implicated in amyloid-ß deposition in vivo, there are few data specifically relating brain metal burden with extent of amyloid pathologies in human brains. Herein brain tissue content of aluminum, iron, and copper are compared with burdens of amyloid-ß, as senile plaques and as congophilic amyloid angiopathy, in 60 aged human brains. Significant observations were strong negative correlations between brain copper burden and the degree of severity of both senile plaque and congophilic amyloid angiopathy pathologies with the relationship with the former reaching statistical significance. While we did not have access to the dementia status of the majority of the 60 brain donors, this knowledge for just 4 donors allowed us to speculate that diagnosis of dementia might be predicted by a combination of amyloid pathology and a ratio of the brain burden of copper to the brain burden of aluminum. Taking into account only those donor brains with either senile plaque scores ≥4 and/or congophilic amyloid angiopathy scores ≥12, a Cu:Al ratio of <20 would predict that at least 39 of the 60 donors would have been diagnosed as suffering from dementia. Future research should test the hypothesis that, in individuals with moderate to severe amyloid pathology, low brain copper is a predisposition to developing dementia.


Assuntos
Alumínio/análise , Peptídeos beta-Amiloides/análise , Encéfalo/patologia , Cobre/análise , Demência/patologia , Ferro/análise , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/patologia , Biomarcadores/análise , Carga Corporal (Radioterapia) , Química Encefálica , Feminino , Humanos , Masculino , Placa Amiloide/química , Placa Amiloide/patologia
4.
Int J Parasitol ; 39(10): 1093-8, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19341741

RESUMO

Over recent years it has been established that pollutants can have a significant impact on host-parasite systems in the aquatic environment, so much so that it has been proposed that parasite fauna may be a useful parameter to monitor water quality. Surprisingly, with perhaps the exception of trematodes and bioaccumulation in adult acanthocephalans, detailed observations on the interaction between helminths, particularly cestodes, and pollutants such as heavy metals, are lacking. In this study, eggs of the carp tapeworm, Bothriocephalus acheilognathi were exposed to a range of cadmium concentrations (0.1, 10, 100 and 10,000 mcirog/L) and coracidial hatching and survival assessed. Results indicated that the egg is highly resistant to heavy metal pollution and hatching occurs even at 10,000 microg/L. In contrast, the activity of the liberated coracidium significantly decreased after 1h exposure to cadmium at 10 and 100 microg/L. Electron microscopic X-ray microanalysis of parasite eggs exposed to 1000 and 10,000 microg/L cadmium revealed that cadmium accumulates on the surface of the egg and does not penetrate detectably into the enclosed coracidium. This means that the parasite eggs may be able to withstand a heavy metal pollutant incident.


Assuntos
Cádmio/toxicidade , Cestoides/efeitos dos fármacos , Embrião não Mamífero/efeitos dos fármacos , Interações Hospedeiro-Parasita/efeitos dos fármacos , Animais , Carpas/parasitologia , Cestoides/embriologia , Cestoides/fisiologia , Microanálise por Sonda Eletrônica , Metais Pesados
5.
J Inorg Biochem ; 101(9): 1344-6, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17629949

RESUMO

Aluminium is omnipresent in everyday life and increased exposure is resulting in a burgeoning body burden of this non-essential metal. Personal care products are potential contributors to the body burden of aluminium and recent evidence has linked breast cancer with aluminium-based antiperspirants. We have used graphite furnace atomic absorption spectrometry (GFAAS) to measure the aluminium content in breast biopsies obtained following mastectomies. The aluminium content of breast tissue and breast tissue fat were in the range 4-437 nmol/g dry wt. and 3-192 nmol/g oil, respectively. The aluminium content of breast tissue in the outer regions (axilla and lateral) was significantly higher (P=0.033) than the inner regions (middle and medial) of the breast. Whether differences in the regional distribution of aluminium in the breast are related to the known higher incidence of tumours in the outer upper quadrant of the breast remains to be ascertained.


Assuntos
Alumínio/análise , Mama/química , Alumínio/farmacocinética , Biópsia , Carga Corporal (Radioterapia) , Mama/metabolismo , Mama/patologia , Feminino , Humanos , Espectrofotometria Atômica
6.
Addict Biol ; 12(2): 197-9, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17508993

RESUMO

The use of illicit heroin is associated with aberrant neurology of unknown aetiology and various psychiatric illnesses. Aluminium, which is a proven neurotoxin, is present in significant amounts in illicit heroin and may also be volatilized and inhaled following the vaporization of heroin off aluminium foil ('Chasing the Dragon'). The purpose of this study was to establish if the use of illicit heroin was associated with an increase in the body burden of aluminium. We have used graphite furnace atomic absorption spectrometry to measure the aluminium and iron contents of the urine of current and past users of illicit heroin and used these data to estimate body burdens of aluminium. Urinary excretion of aluminium is the most effective non-invasive indicator of the body burden of aluminium and was found to be significantly (P < 0.001) higher in users of illicit heroin, range 14-3382 nmol/mmol creatinine (mean +/- SD; 222 +/- 491 nmol/mmol creatinine), than in a normal non-drug abusing control population, range 23-74 nmol/mmol creatinine (mean +/- SD; 43 +/- 19 nmol/mmol creatinine). Exposure to aluminium from the use of illicit heroin may be of particular significance because the urinary excretion of iron, another major contaminant of illicit heroin, in users (mean +/- SD; 53 +/- 63 nmol/mmol creatinine) was not significantly different (P > 0.05) from the control population (mean +/- SD; 38 +/- 18 nmol/mmol creatinine). We have shown for the first time that the use of illicit heroin may be a significant contributor to the body burden of aluminium. Further research will be required to determine if adventitious aluminium has a role in heroin use-related neuropathology and neurology.


Assuntos
Alumínio/urina , Contaminação de Medicamentos , Dependência de Heroína/urina , Heroína/urina , Drogas Ilícitas , Adulto , Carga Corporal (Radioterapia) , Creatinina/urina , Inglaterra , Feminino , Dependência de Heroína/reabilitação , Humanos , Masculino , Espectrofotometria Atômica
7.
Mult Scler ; 12(5): 533-40, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17086897

RESUMO

Multiple sclerosis (MS) is a chronic, immune-mediated, demyelinating disease of the central nervous system of as yet unknown aetiology. A consensus of opinion has suggested that the disorder is the result of an interplay between environmental factors and susceptibility genes. We have used a battery of analytical techniques to determine if the urinary excretion of i) markers of oxidative damage; ii) iron and iii) the environmental toxin aluminium and its antagonist, silicon, are altered in relapsing-remitting (RRMS) and secondary progressive MS (SPMS). Urinary concentrations of oxidative biomarkers, MDA and TBARS, were not found to be useful indicators of inflammatory disease in MS. However, urinary concentrations of another potential marker for inflammation and oxidative stress, iron, were significantly increased in SPMS (P<0.01) and insignificantly increased in RRMS (P>0.05). Urinary concentrations of aluminium were also significantly increased in RRMS (P<0.001) and SPMS (P <0.05) such that the levels of aluminium excretion in the former were similar to those observed in individuals undergoing metal chelation therapy. The excretion of silicon was lower in MS and significantly so in SPMS (P<0.05). Increased excretion of iron in urine supported a role for iron dysmetabolism in MS. Levels of urinary aluminium excretion similar to those seen in aluminium intoxication suggested that aluminium may be a hitherto unrecognized environmental factor associated with the aetiology of MS. If aluminium is involved in MS then an increased dietary intake of its natural antagonist, silicon, might be a therapeutic option.


Assuntos
Alumínio/urina , Ferro/urina , Esclerose Múltipla/urina , Adulto , Análise de Variância , Cromatografia Líquida de Alta Pressão/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Espectrofotometria Atômica/métodos
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