20 research outputs found

    Systematic Review of Potential Health Risks Posed by Pharmaceutical, Occupational and Consumer Exposures to Metallic and Nanoscale Aluminum, Aluminum Oxides, Aluminum Hydroxide and Its Soluble Salts

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    Aluminum (Al) is a ubiquitous substance encountered both naturally (as the third most abundant element) and intentionally (used in water, foods, pharmaceuticals, and vaccines); it is also present in ambient and occupational airborne particulates. Existing data underscore the importance of Al physical and chemical forms in relation to its uptake, accumulation, and systemic bioavailability. The present review represents a systematic examination of the peer-reviewed literature on the adverse health effects of Al materials published since a previous critical evaluation compiled by Krewski et al. (2007). Challenges encountered in carrying out the present review reflected the experimental use of different physical and chemical Al forms, different routes of administration, and different target organs in relation to the magnitude, frequency, and duration of exposure. Wide variations in diet can result in Al intakes that are often higher than the World Health Organization provisional tolerable weekly intake (PTWI), which is based on studies with Al citrate. Comparing daily dietary Al exposures on the basis of “total Al”assumes that gastrointestinal bioavailability for all dietary Al forms is equivalent to that for Al citrate, an approach that requires validation. Current occupational exposure limits (OELs) for identical Al substances vary as much as 15-fold. The toxicity of different Al forms depends in large measure on their physical behavior and relative solubility in water. The toxicity of soluble Al forms depends upon the delivered dose of Al+ 3 to target tissues. Trivalent Al reacts with water to produce bidentate superoxide coordination spheres [Al(O2)(H2O4)+ 2 and Al(H2O)6 + 3] that after complexation with O2•−, generate Al superoxides [Al(O2•)](H2O5)]+ 2. Semireduced AlO2• radicals deplete mitochondrial Fe and promote generation of H2O2, O2 • − and OH•. Thus, it is the Al+ 3-induced formation of oxygen radicals that accounts for the oxidative damage that leads to intrinsic apoptosis. In contrast, the toxicity of the insoluble Al oxides depends primarily on their behavior as particulates. Aluminum has been held responsible for human morbidity and mortality, but there is no consistent and convincing evidence to associate the Al found in food and drinking water at the doses and chemical forms presently consumed by people living in North America and Western Europe with increased risk for Alzheimer\u27s disease (AD). Neither is there clear evidence to show use of Al-containing underarm antiperspirants or cosmetics increases the risk of AD or breast cancer. Metallic Al, its oxides, and common Al salts have not been shown to be either genotoxic or carcinogenic. Aluminum exposures during neonatal and pediatric parenteral nutrition (PN) can impair bone mineralization and delay neurological development. Adverse effects to vaccines with Al adjuvants have occurred; however, recent controlled trials found that the immunologic response to certain vaccines with Al adjuvants was no greater, and in some cases less than, that after identical vaccination without Al adjuvants. The scientific literature on the adverse health effects of Al is extensive. Health risk assessments for Al must take into account individual co-factors (e.g., age, renal function, diet, gastric pH). Conclusions from the current review point to the need for refinement of the PTWI, reduction of Al contamination in PN solutions, justification for routine addition of Al to vaccines, and harmonization of OELs for Al substances

    Bee honey and Nigella sativa inhibit nitric oxide mediated cytochrome C release and down regulation of connexin 43 induced by methylnitrosourea in hepatic tissues of Sprague Dawley rats

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    No Abstract. The Egyptian Journal of Biochemistry and Molecular Biology Vol. 22(2) 2004: 73-8

    Prevalence of neurological disorders in Al Quseir, Egypt: methodological aspects

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    Hamdy El-Tallawy,1 Wafa Farghaly,1 Nabil Metwally,2 Tarek Rageh,1 Ghaydaa A Shehata,1 Reda Badry,1 Esam El Moselhy,2 Mahmoud Hassan,2 Mohamed M Sayed,3 Ahmed A Abdelwarith,1 Y Hamed,2 I Shaaban,2 Talal Mohamed,4 Mohamed Abd El Hamed,1 MR Kandil1 1Department of Neurology, Faculty of Medicine, Assiut University, Assiut, Egypt; 2Department of Neurology and Public Health, Faculty of Medicine, Al-Azhar University (Assiut branch), Assiut, Egypt; 3Department of Neurology, Faculty of Medicine, Sohag University, Sohag, Egypt; 4Department of Neurology, Faculty of Medicine, Qena University, Qena, Egypt Abstract: Methodology and strategy play a very important role in epidemiological studies. Determination of the study area, geographical features, facilities, difficulties, and key personnel from the same area are important factors for successful methodology. Over 31 months (July 1, 2009 to January 31, 2012), a screening and an examination survey were carried out to ascertain the prevalence of epilepsy, stroke, dementia, cerebellar ataxia, migraine, cerebral palsy, Parkinsonism, chorea, athetosis, dystonia, trigeminal neuralgia, Bell's palsy, multiple sclerosis, spinal cord disorders, and attention deficit hyperactivity disorders in Al Quseir, Red Sea Governorate, Egypt. A total of 33,285 people were screened by three neurologists in a door-to-door manner, including every door, using a standardized Arabic questionnaire to detect any subject with a neurological disorder. The methodological aspects of this project were carried out through eight phases: (1) data collection; (2) preparation; (3) screening; (4) case ascertainment; (5) investigations; (6) classifications; (7) data entry; and (8) statistics and tabulations. The results of this study reveal that the total prevalence of neurological disorders in Al Quseir was 4.6% and higher among females (5.2%) than males (3.9%). The highest prevalence was recorded in the elderly population (60+ years [8.0%]) and among the age group 18–39 years (5.4%). Keywords: methodological aspects, demographic data, prevalenc

    Consequences of multiple withdrawal from alcohol

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    This article represents the proceedings of a symposium at the 2003 annual meeting of the Research Society on Alcoholism in Fort Lauderdale, FL, organized by Theodora Duka and chaired by Dai Stephens. The purpose of the symposium was to examine the effects of multiple experiences of withdrawal from alcohol in animals made dependent on alcohol and in humans who are alcohol dependent. Parallels were drawn to the effects of repeated short-lived high-content alcohol exposures in animals and in humans who are social drinkers but indulge in binge drinking. The presentations were (1) Multiple detoxifications and risk of relapse in abstinent alcoholics, by John Gentry and Robert Malcolm; (2) Emotional and cognitive impairments after long-term use of alcohol: relationship to multiple detoxifications and binge drinking, by Theodora Duka; (3) The effect of repeated withdrawal from ethanol on conditioning to appetitive stimuli, by Tamzin Ripley, Gilyanna Borlikova, and Dai Stephens; (4) Alcohol withdrawal kindling: electrographic measures in a murine model of behavioral seizure sensitization, by Lynn Veatch and Howard Becker; and (5) Binge drinking induced changes in CNS, by Fulton Crews
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