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Examines the neuropathology of schizophrenia. Alterations found in the brains of schizophrenic patients; Evidence of diffuse ventricular enlargement; Decrease cortical volume; Involvement of the frontal and temporal lobes.

Abstract: Neurodegenerative diseases exhibit varying and characteristic patterns of regional brain cell death, yet in each disorder there are distinct variations in the relative vulnerability of neurons within targeted brain regions. For example, in Parkinson''s disease (PD) up to 90% of dopaminergic neurons of the ventral tier of the substantia nigra pars compacta are lost at post-mortem, while as few as 25% of dopaminergic neurons in the dorsal tier of this nucleus succumb to the disease process. To date the reasons underlying differential vulnerability of similar neurons within a defined cytoarchitectural region has received little attention. We suggest variations in protein distribution underlies this differential vulnerability. Within the substantia nigra pars compacta the more vulnerable neurons exhibit an increased expression of factors that may contribute to vulnerability (D2 dopamine autoreceptors, GIRK-2 potassium channels, lactotransferrin and the dopamine transporter) while also expressing a relative lack of neuroprotective elements (dopamine vesicle transport protein and a number of trophic and growth factors). Differential distribution of key proteins expressed by individual cells within the same cytoarchitectural brain region may influence the severity and likelihood of common neurodegenerative mechanisms, such as protein aggregation, oxidative stress, neuroinflammation and apoptosis, and thus the eventual fate of individual cells in the disease process. An understanding of how variable protein expression can influence cell survival within the diseased human brain in a range of neurodegenerative disorders may provide avenues for the development of novel strategies to improve the survival of targeted neurons in vivo. [Copyright &y& Elsevier]

Abstract: Ultraviolet (UV) irradiation causes DNA damage in skin cells, immunosuppression and photocarcinogenesis. 1α,25-dihydroxyvitamin D3 (1,25D) reduces UV-induced DNA damage in the form of cyclobutane pyrimidine dimers (CPD) in human keratinocytes in culture and in mouse and human skin. UV-induced immunosuppression is also reduced in mice by 1,25D, in part due to the reduction in CPD and a reduction in interleukin (IL-6. The cis-locked analog, 1α,25-dihydroxylumisterol3 (JN), which has almost no transactivating activity, reduces UV-induced DNA damage, apoptosis and immunosuppression with similar potency to 1,25D, consistent with a non-genomic signalling mechanism. The mechanism of the reduction in DNA damage in the form of CPD is unclear. 1,25D doubles nuclear expression of p53 compared to UV alone, which suggests that 1,25D facilitates DNA repair. Yet expression of a key DNA repair gene, XPG is not affected by 1,25D. Chemical production of CPD has been described. Incubation of keratinocytes with a nitric oxide donor, SNP, induces CPD in the dark. We previously reported that 1,25D reduced UV-induced nitrite in keratinocytes, similar to aminoguanidine, an inhibitor of nitric oxide synthase. A reduction in reactive nitrogen species has been shown to facilitate DNA repair, but in view of these findings may also reduce CPD formation via a novel mechanism. [ABSTRACT FROM AUTHOR]

Abstract: Age-related brain changes are widely documented. Because of differences in measurement methods and case selection, the reported effects of age on regional grey and white matter brain volumes, however, are much more pronounced and widespread in neuroimaging than in postmortem studies. Consequently, the magnitude of the effect that is specific to chronological age remains unresolved. We present postmortem volume measurements for 26 cortical, subcortical and white matter regions, in 24 human brains aged 46–92 years, free of neuropathological abnormalities. Significant age-related loss was observed in anterior and posterior white matter but not in total grey matter volumes. Further analyses on five cortical subregions previously reported to exhibit large age-related loss on MRI yielded negative results. These analyses demonstrate smaller changes with age than those reported in imaging studies. Although this discrepancy between postmortem and imaging studies may partly be explained by the increase in noise of the neuroimaging data with age, our results suggest that healthy brain ageing is a process affecting predominantly white matter not grey matter. [Copyright &y& Elsevier]

Abstract: An increasing body of research suggests that a number of immune mechanisms play a role in degenerative pathways in Parkinson''s disease (PD). In the current work we investigated a posited humoral immune response in this disorder. Sera from PD patients exhibited a significantly enhanced absorbance response on a novel ELISA for anti-melanin antibodies, compared to sera from age-matched control subjects. The enhanced ELISA absorbance response was specific for catecholamine-based melanins and was unrelated to antiparkinsonian dopaminergic medication. Further, the absorbance response was significantly and negatively correlated with disease duration. These data suggest that a specific humoral anti-melanin antibody response is present in PD and is more active in early disease. While the contribution of this novel immune response to the initiation and progression of this disorder is unclear, this finding supports the hypothesis that specific immune responses occurring in PD may respond to therapeutic interventions in this disorder. [Copyright &y& Elsevier]

A response from the author of the article "A phase II randomized controlled trial of nicotinamide for skin cancer chemoprevention in renal transplant recipients" is presented.