Karolinska Institutet

About: Karolinska Institutet is a education organization based out in Stockholm, Sweden. It is known for research contribution in the topics: Population & Poison control. The organization has 46212 authors who have published 121142 publications receiving 6008130 citations.

The 24 fluorescence patterns of the human metaphase chromosomes - distinguishing characters and variability.

Abstract: Certain fluorescent DNA-binding compounds, among them quinacrine mustard and quinacrine, give characteristic banding patterns in human metaphase chromosomes; these patterns can be used to identify all the 24 chromosome types as well as chromosome aberrations. The patterns given by quinacrine mustard are especially clear and stable and are suitable for chromosome identification either visually—preferably after contrast enhancement by photography—or by photometric methods. The typical fluorescence pattern of each chromosome type is described. The reproducibility and variability of the patterns have been analysed by photometric measurements of the patterns in a material of about 5000 chromosomes from 14 healthy subjects. Apart from certain minor but well defined chromosome regions with especially strong fluorescence, which are subject to certain individual variations, the fluorescence patterns were shown to be quite stable and reproducible.

Pharmacogenomics and Individualized Drug Therapy

Abstract: Pharmacogenetics deals with inherited differences in the response to drugs. The best-recognized examples are genetic polymorphisms of drug-metabolizing enzymes, which affect about 30% of all drugs. Loss of function of thiopurine S-methyltransferase (TPMT) results in severe and life-threatening hematopoietic toxicity if patients receive standard doses of mercaptopurine and azathioprine. Gene duplication of cytochrome P4502D6 (CYP2D6), which metabolizes many antidepressants, has been identified as a mechanism of poor response in the treatment of depression. There is also a growing list of genetic polymorphisms in drug targets that have been shown to influence drug response. A major limitation that has heretofore moderated the use of pharmacogenetic testing in the clinical setting is the lack of prospective clinical trials demonstrating that such testing can improve the benefit/risk ratio of drug therapy.

High Consistency of Regional Cortical Thinning in Aging across Multiple Samples

Abstract: Cross-sectional magnetic resonance imaging (MRI) studies of cortical thickness and volume have shown age effects on large areas, but there are substantial discrepancies across studies regarding the localization and magnitude of effects. These discrepancies hinder understanding of effects of aging on brain morphometry, and limit the potential usefulness of MR in research on healthy and pathological age-related brain changes. The present study was undertaken to overcome this problem by assessing the consistency of age effects on cortical thickness across 6 different samples with a total of 883 participants. A surface-based segmentation procedure (FreeSurfer) was used to calculate cortical thickness continuously across the brain surface. The results showed consistent age effects across samples in the superior, middle, and inferior frontal gyri, superior and middle temporal gyri, precuneus, inferior and superior parietal cortices, fusiform and lingual gyri, and the temporo-parietal junction. The strongest effects were seen in the superior and inferior frontal gyri, as well as superior parts of the temporal lobe. The inferior temporal lobe and anterior cingulate cortices were relatively less affected by age. The results are discussed in relation to leading theories of cognitive aging.