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1.
The objective of this study was to determine the total concentration and bioaccessible fraction of aluminium (Al) in 95 different baby food samples and estimate the exposure assessment. Total Al content was determined following oxidative microwave digestion by inductively coupled plasma optical emission spectrometry. An in vitro digestionmethod was optimized to evaluate the bioaccessible fraction. Total concentration and bioaccessibility varied according to the sample composition (saltypurees, fruit purees, infant drinks and petitsuisse). Petit suisse, soy-based drink and salty puree samples presented the highest total Al concentrations of 4170 μg kg−1, 2860 μg kg−1 and 2760 μg kg−1, respectively. Bioaccessiblefraction varied from 0.5%–48% according to their composition.Exposure to Al was estimated and compared with the tolerable weekly intakes currently established. The results showed that the consumption of 3 portions/day of soy-based drink along the week could represent a concern.  相似文献   
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Objectives: Alzheimer’s disease (AD) is a neurodegenerative disorder characterized by progressive pathological changes of the brain. A number of studies demonstrated compelling evidence of the importance of oxidative processes in AD pathogenesis. Raisin contains polyphenol, phenolic acid, and tannin compounds, which have antioxidant and anti-inflammatory properties. The present study was aimed to evaluate the protective effect of raisin on neurobehavioral and histological changes in rats with Alzheimer.

Methods: Animal model of AD was induced by intraperitoneal injection of aluminium chloride for 60 days (100?mg/kg body weight). During these 60 days both Alzheimer’s and control rats were given 6?g of raisin per rat. At the end of the treatment, blood was collected for biochemical assessment. We used a Morris water task and passive avoidance test to assess spatial memory.

Results: Our results showed that aluminium exposure significantly decreased the memory in the MWT and passive avoidance test, but in the raisin?+?AlCl3 group, it significantly increased spatial memory in both tests. Also, Aluminium exposure significantly increased malondialdehyde (MDA) and decreased ferric reducing ability of plasma (ferric reducing/antioxidant power (FRAP)), while treatment with raisin significantly decreased MDA and increased FRAP in plasma of blood.

Discussion: Our findings showed that raisin has a neuroprotective effect and improves the spatial memory in AD animal models.  相似文献   

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Purified vaccine antigens offer important safety and reactogenicity advantages compared with live attenuated or whole killed virus and bacterial vaccines. However, they require the addition of adjuvants to induce the magnitude, duration and quality of immune response required to achieve protective immunity.Aluminium salts have been used as adjuvants in vaccines for almost a century. In the literature, they are often referred to as aluminium-based adjuvants (ABAs), or aluminium salt-containing adjuvants or more simply “alum”. All these terms are used to group aluminium suspensions that are very different in terms of atomic composition, size, and shape. They differ also in stability, antigen-adsorption, and antigen-release kinetics. Critically, these parameters also have a profound effect on the character and magnitude of the immune response elicited. Recent findings suggest that, by reducing the size of aluminium from micro to nanometers, a more effective adjuvant is obtained, together with the ability to sterile filter the vaccine product. However, the behaviour of aluminium nanoparticles in vaccine formulations is different from microparticles, requiring specific formulation strategies, as well as a more detailed understanding of how formulation influences the immune response generated. Here we review the current state of art of aluminium nanoparticles as adjuvants, with a focus on their immunobiology, preparation methods, formulation optimisation and stabilisation.  相似文献   
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Aluminium (Al) is the most common metal and widely distributed in our environment. Al was first isolated as an element in 1827, and its use began only after 1886. Al is widely used for industrial applications and consumer products. Apart from these it is also used in cooking utensils and in pharmacological agents, including antacids and antiperspirants from which the element usually enters into the human body. Evidence for the neurotoxicity of Al is described in various studies, but still the exact mechanism of Al toxicity is not known. However, the evidence suggests that the Al can potentiate oxidative stress and inflammatory events and finally leads to cell death.Al is considered as a well-established neurotoxin and have a link between the exposure and development of neurodegenerative diseases, including Amyotrophic Lateral Sclerosis (ALS), Alzheimer’s disease (AD), dementia, Gulf war syndrome and Parkinsonism. Here, we review the detailed possible pathogenesis of Al neurotoxicity. This review summarizes Al induced events likewise oxidative stress, cell mediated toxicity, apoptosis, inflammatory events in the brain, glutamate toxicity, effects on calcium homeostasis, gene expression and Al induced Neurofibrillary tangle (NFT) formation. Apart from these we also discussed animal models that are commonly used for Al induced neurotoxicity and neurodegeneration studies. These models help to find out a better way to treat and prevent the progression in Al induced neurodegenerative diseases.  相似文献   
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We describe a lethal poisoning in a healthy woman caused by deliberate ingestion of aluminium phosphide (AlP), a pesticide used to kill rodents and insects. Toxicity of AlP and review of cases reported to the National Poisons Information Service (London) 1997-2003 are discussed.  相似文献   
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Different forms of aluminium (Al) are environmental xenobiotics that induce free radical-mediated cytotoxicity and reproductive toxicity. Propolis has been reported to be important antioxidant. Therefore, this study aimed at elucidating the protective effects of propolis against reproductive toxicity of aluminium chloride (AlCl3) in male rats. The first group served as control. Group 2 received 34 mg AlCl3/kg bw (1/25 LD50). Group 3 was administered 50 mg propolis/kg bw/day. Group 4 was treated with AlCl3 plus propolis. Treatment was continued for 70 days. AlCl3 caused a decrease in testes, seminal vesicle and epididymis weights, sperm concentration, motility, testosterone level and the activities of 17-ketosteroid reductase, CAT and GST, and GSH content. While, dead and abnormal sperm and testes TBARS concentrations were increased. In the AlCl3-treated group, histopathologic examinations revealed apparent alterations in the testes, where it induced marked lesions in seminiferous tubules. Propolis alone decreased dead and abnormal sperm and TBARS, and increased testosterone, GSH, 17-ketosteroid reductase, CAT and GST. Results showed that propolis antagonized the harmful effects of AlCl3. This was proved histopathologically by the great improvement in testes. In conclusion propolis could be effective in the protection against the reproductive toxicity of AlCl3.  相似文献   
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Aluminium is widely used in medicines, as food additives, as water purification agent, as in the making of household cookware and storage utensils. Aluminium absorption depends on the chemical form of aluminium taken up. Aluminium hydroxide and chlorides are absorbed more efficiently than its phosphorus and fluorine compounds. As aluminium is stored mainly in the liver,1 the present work is conducted to study the morphological and morphometric changes in the liver produced by aluminium chloride(AICI3). 20 inbred adult albino rats weighing 150–200gm each were administered 37.5mg per day of aluminium chloride orally for 21 days with maintenance of 20 similar controls. A small piece of liver tissue was processed for paraffin sections. 7μ thick sections were stained with hematoxylin and eosin stain and observed under light microscope. The changes were observed at tissue and cellular level along with general architectural derangement, degenerative changes and nuclear variations such as karryorrhexis, pyknosis. These findings are highly conclusive of toxic hepatitis.  相似文献   
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A process was developed for the microencapsulation of inorganic filler particles with poly-methyl-methacrylate, to increase the interaction between the hydrophilic filler particles and a polymer matrix. The filler utilised was aluminium hydroxide with an average diameter of 1.9 µm and a specific surface area of 5 m2/g. The process comprised a surface modification, in which a monolayer of isopropoxy titanium isostearate was chemically bound to the surface to render it hydrophobic and to ensure a chemical bond between the filler and the organic phase. Then, an encapsulation reaction was carried out by means of an emulsion-like polymerization process at monomer starved conditions. The modified particles were stabilized in water with sodium-dodecyl-sulphate. A redox system consisting of cumene-hydroperoxide in combination with sodium-formaldehyde-sulphoxylate and iron(II) salt was applied for the initiation of the polymerization. Besides surface polymer, free polymer particles were also formed. The parameters which varied were the filler concentration, the concentration of the initiator components and the surfactant concentration. At optimum conditions, ~50% of the added monomer polymerized at the modified filler surface, thus forming encapsulated filler particles. SEM together with TGA analysis indicated that a smooth polymer layer had been formed on the filler surface. At high filler loading, however, coagulation occurred.  相似文献   
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