Biomedical subjects
Publications and source records attributed to L Klinken.
After injection of a mixture of carbon black and a iodinated X-ray contrast medium into the cerebral ventricles of rats carbon black loaded macrophages were found in the alveolar septa in the lungs. It is concluded that contrast media used in cerebral ventriculography are eliminated at least partly by discharge of pulmonary macrophages.
In 44 children with benign cerebellar astrocytoma, operated on between 1935 and 1959, two histological types could be distinguished, namely, a so-called juvenile type (31 children) and a diffuse type (13 children). All the children were followed to April, 1976, and the histological review was performed without knowledge of the survival in the single patient. For children with the juvenile type of cerebellar astrocytoma the 25-year cumulative survival rate was 94%, as against 38% for children with the diffuse type. It has thus been demonstrated that the morphological difference between the two types corresponds to a marked difference in survival rate.
Nuclear size and density were determined in brain regions with different glial--neurone composition in rats up to 35 weeks after porto-caval anastomosis. In the white matter, i.e. corpus callosum, both the total cell count and the percentage of astrocytes and oligodendrocytes were unchanged. In the corpus striatum, where the glial/neurone ratio is about 1, the number of nuclei registered as astrocytes increased, and after 35 weeks astrocytes comprised 29% of glial cells (compared with 15% in controls). However, the number of oligodendrogial nuclei decreased simultaneously, leaving the total glial number unchanged. In the animals with longest experimental period there was a 15% loss of neurones. In a region with higher glial/neurone ratio, i.e. the Purkinje cell layer, the neurones showed a similar reduction, whereas the number of Bergmann astrocyte nuclei increased less than striatal astrocytes. A small group of animals with pronounced signs of encephalopathy had a higher loss of neurones and, furthermore, the glial number in corpus striatum and callosum was reduced, due to loss of oligodendrocytes. Despite the use of perfusion fixation, the size of astrocyte nuclei increased, this was reversible, as only slight changes were seen after 35 weeks. A possible explanation of the increase in astrocyte nuclear count and decrease in oligodendroglial count could be that nuclei normally considered to be oligodendroglial are transformed into nuclei with morphological characteristics of astrocytes.
281 histologically verified brain tumours in children were revised and reclassified according to degree of histological malignancy. Survival graphs based on 100 per cent follow-up after 15-40 years show that, of those who survived for more than 1 month after diagnosis and possible operation, 40 per cent were still alive more than 15 years later. There was a clear correlation between survival and degree of malignancy. Sixty-five per cent of those with tumours of malignancy grade I and only 3 per cent of those with malignancy grade IV were alive after 15 years.
Neuropathological findings were studied in 74 patients with drug-resistant temporal lobe epilepsy who underwent unilateral temporal lobe resection in 1960-1969 in Denmark. In 60 per cent of the patients a well-defined neuropathological abnormality was revealed (i.e. 13 cases of focal lesions, including four small tumours, 21 cases of gliosis, and 10 cases of perivascular infiltration), in 23 per cent the findings were either questionably abnormal or without structural abnormality, while in the last 18 per cent sequelae of a previous operation dominated the histology. The general trend was for the postoperative clinical outcome to be better, the more specific and circumscribed the histological abnormality. There was no correlation between the neuropathological findings and the preoperative types of seizures. Postoperative recurrence of seizures was more often observed in patients with gliosis than in those with other histological diagnoses. A positive correlation existed between a history of cerebral infection and the presence of perivascular lymphocytic and histiocytic infiltration, and gliosis was a frequent finding in patients with epilepsy of unknown aetiology. No other significant correlation was found between the neuropathological abnormalities and the clinical, hereditary, aetiological, and social aspects.
Following injections of iodophendylate (Pantopaque) in adult rats, the contrast medium was shown to be refrained in the dilated cerebral ventricles for at least 180 days. Histological examination revealed macrophages containing phagocytosed lipid on the ependymal lining of the ventricles, but there was no leukocytic reaction to retained or encysted contrast material. The macrophages were considered to be involved in the removal of iodophendylate. The irritative reaction in the normal central nervous system was limited, as opposed to the severe reactions previously reported in animals with inflammation of the brain and meninges.
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A histological examination was performed on tails from three groups of pigs, comprising 10 amputated tail tips from day-old piglets, 10 tails from undocked fattening pigs and 20 tails from docked fattening pigs. The investigation demonstrated that peripheral nerves could be traced to the tip of the tails of day-old piglets as well as of fattening pigs. In the docked fattening pigs, the peripheral nerves were unevenly distributed and showed regressive changes. In some cases traumatic neuromas were found, indicating an increased sensitivity to pain in the amputation stump. It was, surprisingly, demonstrated that widespread inflammatory reactions could be found in the apparently healthy tails of both categories of fattening pigs, presumably due to pen-mates' chewing activities.
The occurrence of secondary brain stem hemorrhage was studied in 435 autopsies from patients with recent cerebral hemorrhage, infarction or ruptured cerebral aneurysms. The frequency of secondary brain stem hemorrhage was found to be 45% in cerebral hemorrhage, 15% in cerebral infarction, and 36% in ruptured aneurysms. In the majority of cases the secondary brain stem hemorrhage occurred a few days after the onset of cerebral hemorrhage or infarction. Ruptured aneurysms showed a more widespread temporal distribution of secondary brain stem hemorrhage. The median survival time was 2 days in cases of cerebral hemorrhage, 4 days in ruptured aneurysm and 4 days in cerebral infarction. The frequency of secondary brain stem hemorrhage was significantly lower in patients younger than 20 years. No significant difference was found in its distribution between the sexes. Secondary occipital lobe infarction was present in 3.5% of the patients. It is concluded that secondary brain stem hemorrhage is a common major contribution to the cause of death in stroke.
Six cases of completed ischemic stroke in the middle cerebral artery territory of more than two months' duration were selected for this study of neuropathology. Coronal brain slices of the entire brain were cut for histology and stained with Klüver-Barrera's stain. Neuronal and glial cell density, and cortex thickness were measured at various distances from the border of the infarct. Corresponding counting points in the contralateral hemisphere served as control in all cases. The density of histologically intact neurons was in all cases normal at a distance of 0.5 cm or more from the border of the infarcts. In one half of the cases the border zone between infarcted and normal tissue was less than a few cells in thickness. This study of old brain infarcts confirms the commonly held view that there is an abrupt transition between infarcted and normal tissue. This observation suggests that the wide zone of low blood flow and metabolism surrounding cerebral infarcts is not caused by selective loss of neurons. Instead, we hypothesize that such change in blood flow and metabolism is the result of neuronal disconnection and cortical deactivation.
The immunoprofile of 76 human pituitary adenomas was studied with particular reference to the occurrence of entrapped, non-neoplastic pituitary cells. This phenomenon was defined as unevenly distributed, usually peripherally located cells forming less than 1% of the total cell population. The stellate contour of such passively incorporated cells departed from the more rounded shape of most principal, neoplastic cells. Thirty-six of the adenomas studied comprised one or more types of entrapped elements. According to the hormone produced, prolactin-(PRL-)cells most commonly occurred as a minor "foreign" component (seen in 23 of the adenomas), whereas growth hormone-(GH-) and adrenocorticotropic hormone-(ACTH-)cells rarely were trapped (seen in 5 and 4 of the adenomas. Entrapped follicle stimulating hormone-(FSH-), luteinizing hormone-(LH-), and thyroid-stimulating hormone-(TSH-)cells assumed an intermediate position (seen in 14, 17 and 15 of the adenomas, respectively).