23 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

    An ALYREF-MYCN coactivator complex drives neuroblastoma tumorigenesis through effects on USP3 and MYCN stability

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    To achieve the very high oncoprotein levels required to drive the malignant state cancer cells utilise the ubiquitin proteasome system to upregulate transcription factor levels. Here our analyses identify ALYREF, expressed from the most common genetic copy number variation in neuroblastoma, chromosome 17q21-ter gain as a key regulator of MYCN protein turnover. We show strong co-operativity between ALYREF and MYCN from transgenic models of neuroblastoma in vitro and in vivo. The two proteins form a nuclear coactivator complex which stimulates transcription of the ubiquitin specific peptidase 3, USP3. We show that increased USP3 levels reduce K-48- and K-63-linked ubiquitination of MYCN, thus driving up MYCN protein stability. In the MYCN-ALYREF-USP3 signal, ALYREF is required for MYCN effects on the malignant phenotype and that of USP3 on MYCN stability. This data defines a MYCN oncoprotein dependency state which provides a rationale for future pharmacological studies

    Long-term results of the direct repair of spondylolisthesis

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    Direct repair of spondylolisthesis can save a functional segment in young patients with slight slipping. Since 1968 many surgeons have proposed different technical solutions to obtain the isthmic repair. Their results changed according to the technique used, the extent of listhesis and the age of the patient. The aim of our study was to perform a retrospective review on the long-term results of the direct repair of spondylolisthesis, according to the different techniques used. We operated 62 patients for isthmic repair, with three different techniques, from 1994 to 2007. We analysed the clinical and radiographic results of 52 cases, with an average follow-up of 9 ± 3 years (range 2–15). Ten patients were lost to the follow-up. The results were different depending on the technique used. Good or excellent clinical outcome by Odom’s criteria were observed in the 83.3% of patients operated with the modified Scott technique. These results are better than those obtained in the group of patients operated with the Scott (62.5%) and the Buck technique (28.5%). Patients with clinical and radiological failure, who then underwent spinal fusion, were 57% with the Buck technique, 12.5% with the Scott technique and 2.7% with the Scott modified technique. The reasons for a new operation were symptomatic pseudarthrosis and progression of slipping. In conclusion, the pars defect repair is a helpful technique in lumbar spondylolisthesis, especially in young patient with slight slipping and painful symptoms resistant to conservative treatment. In our experience, the modified Scott technique seems to provide a better outcome than the Scott and Buck techniques

    Traumatic brain injury and amyloid-ÎČ pathology: a link to Alzheimer's disease?

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    Traumatic brain injury (TBI) has devastating acute effects and in many cases seems to initiate long-term neurodegeneration. Indeed, an epidemiological association between TBI and the development of Alzheimer's disease (AD) later in life has been demonstrated, and it has been shown that amyloid-ÎČ (AÎČ) plaques — one of the hallmarks of AD — may be found in patients within hours following TBI. Here, we explore the mechanistic underpinnings of the link between TBI and AD, focusing on the hypothesis that rapid AÎČ plaque formation may result from the accumulation of amyloid precursor protein in damaged axons and a disturbed balance between AÎČ genesis and catabolism following TBI

    Do patient and ward-related characteristics influence the use of coercive measures? Results from the EUNOMIA international study

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    This study was funded by a grant from the European Commission (Quality of Life and Management of Living Resources Programme, contract number QLG4-CT-2002-01036
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