Biomedical subjects

E Englund

Publications and source records attributed to E Englund.

41 records · Page 3Linked to original sources

PubMedDate not supplied

Neuropathological brain mapping.

Neuropathological brain mapping is enabled by extensive semiserial sectioning with whole brain coronal microscopical sections prepared from every 5 to 15 mm. By this method not only type of change but also distribution and regional severity can be assessed, which is fundamental for a correct neuropathological diagnosis. This has proved to be of vital importance for the correlation and validation of the clinical symptoms and brain imaging findings in cases of organic dementia, and vice versa for the interpretation of the neuropathological findings. Different patterns for the distribution and types of changes have been revealed for Alzheimer's disease and frontal lobe degeneration, as well as in vascular dementia where pure subgroups could be identified. In the very aged, the mapping of several types of mild lesions have been shown to cooperate to cause a summational dementia.

Alzheimer Disease↗

PubMedDate not supplied

Proton magnetic resonance relaxation times T1 and T2 related to postmortem interval. An investigation on porcine brain tissue.

In order to establish the validity of in vitro determination of the proton magnetic resonance (MR) relaxation times T1 and T2 in brain tissue at increasing time delay after death or operative excision, 81 brain tissue samples from 23 pigs were analyzed repeatedly. These samples, representing cortex, caudate nucleus and white matter, were studied microscopically after MR measurements. The T1 values exhibited no time dependence and the T2 values decreased slightly during the interval 2 to 90 hours after death. The samples were stored at +8 degrees C between the measurements. These results indicate that reliable in vitro measurements can be obtained in autopsy or surgical brain tissue specimens within 90 hours after death or excision, if handled properly.

Animals↗

PubMedDate not supplied

Regional differences in the proton magnetic resonance relaxation times T1 and T2 within the normal human brain.

The proton magnetic resonance (MR) relaxation times T1 and T2 were determined in autopsy specimens from 13 different regions of normal human brains. One hundred and seventy-four tissue samples from 25 brains were examined in a pulsed MR analyzer of 0.25 T and were then also studied histologically. There were regional differences in T1 and T2 within the cerebral gray matter but not within the white matter. These regional differences might reflect the different composition and cytoarchitectonic structure of the cortical regions and should be taken into consideration in the interpretation of cortical lesions on MR images.

Aged↗

PubMedDate not supplied

Tumours of the central nervous system. Proton magnetic resonance relaxation times T1 and T2 and histopathologic correlates.

Proton MR relaxation times T1 and T2 were determined in vitro in 136 small specimens of astrocytomas grades I-IV, of oligodendrogliomas, metastases of adenocarcinomas, meningiomas and acoustic neuromas. In addition, 7 samples of peritumoural white matter were analysed. The analysed specimens were studied microscopically in their entirety regarding tumour type and occurrence of necrosis and non-tumour tissue admixture, such as fibrosis and haemorrhage. Most of the gliomas had longer relaxation times than normal white matter and T2 was significantly longer than in the other three tumour groups. The metastases had longer T1 than normal white matter, while T2 varied. The astrocytomas tended to show shorter relaxation times with increasing degree of malignancy, and shortening of T1 and T2 correlating with the proportion of tissue necrosis. Similarly, the metastases with tissue necrosis had shorter T1 and T2 than non-necrotic samples. The meningiomas had T1 values comparable with normal cortex, while the T2 values varied. Tumours containing a large proportion of fibrous tissue had shorter relaxation times than the others. Acoustic neuromas had only slightly longer T1 than normal white matter, while T2 was not prolonged. Both T1 and T2 were significantly shorter than in all other tumours studied. Peritumoural white matter had prolonged relaxation times compared with normal white matter, correlating to increased water content. These in vitro differences regarding relaxation times in various types of tumours of the central nervous system, dependent on various types of tissue alterations, should be of interest for the interpretation of in vivo images.

Adenocarcinoma↗

PubMedDate not supplied

Immunotreatment in patients with glioblastoma multiforme--a histopathological evaluation of reactive and inflammatory changes.

Glioblastoma multiforme (GBM) is the most common highly malignant brain tumor and is also one among the most therapy-resistant human neoplasias. At the University Hospital in Lund, a group of patients with GBM were treated with a new therapy form attempting immunization by glioma cells transfected to produce interferon-gamma. The purpose of this report was to evaluate tumor material from the first nine patients treated with this therapy, assessing the levels of inflammatory/reactive cells (lymphocytes and macrophages). Tumor biopsies from surgery performed at different time points during treatment were analyzed with conventional histotechnical methods and immunohistochemistry. A post-mortem neuropathological investigation with a whole brain assessment was achieved in 5 immunized patients. The results show that cytotoxic T lymphocytes exhibited a mild increase during immunotreatment. This increase indicates an invoked stimulation of a cytotoxic T cell reaction, which may prove beneficial when immunization is adequately manipulated in dosage and timing.

Aged↗