Comprehensive analysis of epigenetic clocks reveals associations between disproportionate biological ageing and hippocampal volume

The concept of age acceleration, the difference between biological age and chronological age, is of growing interest, particularly with respect to age-related disorders, such as Alzheimer’s Disease (AD). Whilst studies have reported associations with AD risk and related phenotypes, there remains a lack of consensus on these associations. Here we aimed to comprehensively investigate the relationship between five recognised measures of age acceleration, based on DNA methylation patterns (DNAm age), and cross-sectional and longitudinal cognition and AD-related neuroimaging phenotypes (volumetric MRI and Amyloid-β PET) in the Australian Imaging, Biomarkers and Lifestyle (AIBL) and the Alzheimer’s Disease Neuroimaging Initiative (ADNI). Significant associations were observed between age acceleration using the Hannum epigenetic clock and cross-sectional hippocampal volume in AIBL and replicated in ADNI. In AIBL, several other findings were observed cross-sectionally, including a significant association between hippocampal volume and the Hannum and Phenoage epigenetic clocks. Further, significant associations were also observed between hippocampal volume and the Zhang and Phenoage epigenetic clocks within Amyloid-β positive individuals. However, these were not validated within the ADNI cohort. No associations between age acceleration and other Alzheimer’s disease-related phenotypes, including measures of cognition or brain Amyloid-β burden, were observed, and there was no association with longitudinal change in any phenotype. This study presents a link between age acceleration, as determined using DNA methylation, and hippocampal volume that was statistically significant across two highly characterised cohorts. The results presented in this study contribute to a growing literature that supports the role of epigenetic modifications in ageing and AD-related phenotypes

Prevalence of Abuse of Ophtalmic Anesthetic Drops among Welders in Kerman City (2007)

Abstract: Background & Aims: Abuse of topical anesthetic drops causes serious ocular complications. Obtaining information about the prevalence of anesthetic drops abuse among high risk groups specially welders is necessary for taking appropriate strategies for prevention. The present study aimed at determining the prevalence of anesthetic drops abuse among welders in Kerman. Methods: In this cross-sectional study, 390 welders selected randomly were asked for the consumption of anesthetic drops by using a questionnaire. Data were analyzed by SPSS 11.5 software. Results: In whole, 314 ones (80.5%) said that they use tetracaine and of whom 295 ones (93.9%) had used the drug frequently. Lack of time for referring to Physician, high cost of visiting by physicians, spontaneous relief of symptoms and no other therapeutic measure by physicians were the most important reasons of self-treatment in welders. In whole, 216 ones (69.3%) had heard about these drugs from their coworkers, 85 ones (27.2%) from physicians, 51 ones (16.3%) from pharmacy personnel and 9 ones (2.9%) from their family members. The prevalence of abuse was significantly higher in those with post secondary educational level (P<0.05). Most of the subjects (97.4%) had got the drugs from pharmacies and without prescription. Conclusion: High prevalence of anesthetic drops abuse among welders and probably other similar jobs and educated people, their prescription by general practitioners and their selling in pharmacies without prescription requires more serious measures for prevention. Keywords: Anesthetics, Topica