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L Klinken

Publications and source records attributed to L Klinken.

At least 37 records · Page 2Linked to original sources

Pathology of brain and eye in the acquired immune deficiency syndrome (AIDS). A comparison of lesions in a consecutive autopsy material.

During the years 1984-1987, a consecutive Danish autopsy material of 43 AIDS cases was analysed in order to investigate a possible coincidence of pathological changes in brain and eye. In the brain, nodular gliosis/encephalitis was most frequent, followed by cytomegalovirus infection, which occurred twice as frequently as toxoplasmic infection and four times as frequently as fungal infection. In the eye, cytomegalovirus infection was most frequent and the only opportunistic infection, followed by retinal gliosis and cytoid body lesion. Malignant lymphoma was present in the brain in three patients, and in the choroid in two of these. In 11 patients, no changes of the brain were found. In eight of these the eye was also without pathological findings, while three had minor changes. In 22 patients the eye was normal, but in only eight of these was the brain without changes. Eight had nodular gliosis, and four a specific infection, while multifocal leucoencephalopathy and unspecified abscess each occurred in one patient. Comparison of the three opportunistic infections--CMV, toxoplasmosis and mycosis--in the three-year period showed an overall decreasing frequency, attributed to better medical care. It is concluded that concomitance of identical pathological lesions in brain and eye is less frequent than was expected.

Acquired Immunodeficiency Syndrome↗

Neuropsychiatric studies in a family with presenile dementia different from Alzheimer and Pick disease.

We have studied a family in which 14 persons among 73 are or have been suffering from presenile dementia. Post mortem examination showed atrophy but no sign of any known demential syndrome. Cerebral blood flow measured in the late stage of disease was low, but with no characteristic pattern in flow distribution. In one patient in the initial stage of disease, the cerebral blood flow was unexpectedly increased. The patients with presenile dementia in this family did not reveal pathological signs of any known demential syndrome and showed CBF-changes not earlier reported. Moreover, contrary to widely held views we have evidence that dementia may be connected to a high blood flow at least in the initial state. An increased blood flow was also seen in seven of ten well functioning first degree relatives, in some cases along with cerebral atrophy and/or psychological tests with signs of dementia. Are these people going to develop manifest dementia later in life?

Aged↗

Patho-anatomical studies in patients dying of AIDS.

The incidence of AIDS in Denmark is the highest reported among the countries of Western Europe. This preliminary account is a report of the autopsy findings in 10 patients, 9 homosexual men and 1 woman. Our aim is to provide a detailed description of the patho-anatomical findings, as well as to compare these with corresponding results reported from the United States, with a view to establishing possible geographical differences in the disease picture. The results of the patho-anatomical studies correspond in all essentials to those from the United States. However, it must be stated that no malignant lymphomas were demonstrated in our patients, although the disease can give rise to very pronounced, possibly transitory, lesions in the lymphatic tissue, easily misinterpreted as malignant. Further features that should be emphasized are the often widespread mycobacterial infection found in the intestinal wall in protracted cases, the occurrence of CMV vasculitis, particularly in the adrenal cortex and medulla, and thromboembolic lesions, often demonstrated in a variety of tissues. The studies made so far emphasize the importance of autopsy in AIDS deaths, as it has extended our detailed knowledge of the patho-anatomical lesions associated with certain opportunistic infections. Further, the autopsy findings have been demonstrably significant either for confirming or for rejecting the clinical diagnosis. On the basis of an analysis of the cellular immunological profile in AIDS, parallels can be drawn to the conditions in certain lymphoproliferative diseases. In autopsied AIDS cases, we recommend a standard scheme covering the tissue specimens to be obtained for histological examination. Strict safety precautions should be observed against infection during autopsy.

Acquired Immunodeficiency Syndrome↗

Periphlebitis retinae in multiple sclerosis. A histopathological study of two cases.

The reported findings of periphlebitis retinae (PR) at autopsy, in which brain autopsy was also performed, in 2 patients with multiple sclerosis (MS) are, so far as the authors are aware, the first histological account of this manifestation of the disease. The similarity between the cellular accumulations around the veins of the central nervous system seen in multiple sclerosis and the periphlebitic cellular accumulations here described suggests that periphlebitis is an initial event in plaque formation.

Adult↗

Blood-brain and blood-spinal cord barrier permeability during the course of experimental allergic encephalomyelitis in the rat.

Experimental allergic encephalomyelitis (EAE) was induced in young male Lewis rats. Blood-brain barrier permeability to radiotracers of different molecular sizes was studied at intervals after induction using a tissue sampling technique. The results were correlated to the clinical picture and to the histological appearance of the central nervous system. Significant increase in blood-brain barrier permeability to small molecules was found to precede clinical symptoms by one day in the lumbar spinal cord and to coincide with the onset of clinical disease in other regions. In all regions, increased blood-brain barrier permeability preceded the occurrence of histological lesions (perivascular cellular infiltrates). No permeability increase to large molecules could be demonstrated.

Animals↗

Calcified acoustic neurinoma.

An unusual case history of a patient with an acoustic neurinoma is reported. The patient had a two-year history of unilateral sensori-neural hearing impairment, normal radiological appearance of the internal acoustic meatus at tomography and on CT a grossly calcified tumour in the cerebello-pontine angle, indicating pathology other than an neurinoma. Vertebral angiography was normal, and at surgery a grossly calcified tumour was found, while microscopy revealed a typical neurinoma pattern. The tumour had to be removed in two stages, both via the translabyrinthine approach, with a satisfactory post-operative condition, including near-normal facial function. It is concluded that dense calcifications in tumours in the cerebello-pontine angle do not necessarily exclude a neurinoma, and vertebral angiography is therefore not indicated routinely. However, such findings do predict difficulties at surgery.

Adult↗

Meniere's disease: peripheral or central origin. A neuroanatomical study.

Previous clinical and histological studies have suggested that the aetiology of Meniere's disease should be sought not only in the endolymphatic hydrops, but also in pathological changes of the brain and brain stem. Moreover, neuropsychological studies have indicated some centralization of the disease, whether it be primary or secondary. In order to elucidate this problem further we have examined the temporal bones and brains of 4 patients with Meniere's disease, who died of diseases unrelated to the inner ear or the central auditory and vestibular pathways. Endolymphatic hydrops was found in 6 temporal bones to a varying degree, as well as degeneration of the ganglion cells. The brain stem was divided by many horizontal sections from the rostral border of the superior colliculi above, to 15 mm caudal to the border between pons and medulla below. The principal nuclei and fascicles, the intra- and extraparenchymatous vessels and the leptomeninges were examined. The morphology of ganglion and glial cells was studied. Myelin sheaths were investigated for focal or diffuse demyelination, and the axons were observed. In addition, vessels and leptomeninges were studied for atherosclerosis and fibrosis. The brain autopsies did not reveal any changes, either locally or diffusely, which could support central pathoanatomical lesions as being responsible for the symptoms in Meniere's disease.

Aged↗

Familial aggregation of neuroectodermal and gastrointestinal tumors.

A family with multiple tumors is presented. Four cases were childhood neoplasms derived from the neuroectoderm, as was a malignant melanoma in a young female and a branchiogenic cyst in her brother. He also had an early onset of an adenocarcinoma of the transverse colon. Four further cases of gastrointestinal tumors and one case of acute myelogenous leukemia had occurred in the family. One of the childhood tumors was a bilateral retinoblastoma. It is discussed as to whether the tumors in the studied family were due to a genetic factor resulting in a neuroectodermal embryopathy, or were caused by a retinoblastoma gene with a pleiotropic effect.

Adult↗

Prediction of recurrence in meningiomas after surgical treatment. A quantitative approach.

The prognostic significance of nuclear count, nuclear area fraction, and mean nuclear area estimated by automatic image analysis was evaluated in benign meningiomas. One hundred thirty-two meningiomas without recurrences, 39 meningiomas that recurred, and 40 first recurrences were examined. The tumors were classified according to age and sex of patients, localization, and histology; and the correlation between these parameters and the recurrence rate was assessed. The nuclear counts were identical in paraffin sections from meningiomas without recurrences (6.1 nuclei per 1,000 micrometer 2) and in meningiomas that recurred (6.4 nuclei per 1,000 micrometer 2). The cell count in the recurrences (7.4 nuclei per 1,000 micrometer 2) was higher than in the primary tumors. The same relationship was found for the nuclear area fractions, which were identical in meningiomas without recurrences and in primary meningiomas that recurred. The nuclear area fraction was increased in recurrences. The mean nuclear areas were identical in all groups. The histological type was of little significance in prediction of recurrence rate, although bone invasion and necrosis were of some significance. We found a higher recurrence rate in parasagittal meningiomas. Meningiomas that recurred appeared in a younger age group than other meningiomas, and the recurrence rate was higher for males than for females.

Adolescent↗

Histopathology of eye, optic nerve and brain in a case of dominant optic atrophy.

Histopathology of eye, optic nerve and brain was performed in a patient with typical signs and symptoms of dominant optic atrophy. He belonged to a previously-reported family of 152 members in which optic atrophy was demonstrable in 14 persons, and probably present in a further 8 cases. In the eyes, fibrosis of the retinal ganglion cell layer and disc was found. Ultrastructural examination showed a few remaining cells in this layer, heavy fibrosis and in particular a highly condensed inner limiting membrane. The optic nerves, the optic chiasm and optic tracts showed an increased content of collagen tissue and a decreased number of neurofibrils and myelin sheaths. In the lateral geniculate body there was massive loss of ganglion cells, fibrillary gliosis and a great quantity of fine granular lipid in the cytoplasm of the ganglion cells. No changes in the calcarine cortex were observed. Examination of the intracranial part of both vestibulocochlear nerves showed a decreased number of neurofibrils and myelin sheaths. It is concluded that the histopathological changes of the visual system are similar to those in Leber's disease, but less pronounced. The study confirms earlier theories that dominant optic atrophy is a primary degeneration of the ganglion cell layer in the retina, with ascending optic atrophy.

Aged↗

Computed tomography of benign supratentorial astrocytomas of infancy and childhood.

The CT findings of 15 benign supratentorial astrocytomas in children less than 15 years of age are compared with the CT findings of 19 supratentorial tumors of other histological types in the same age group. Astrocytomas were more often hypodense, lacked calcification and showed greater contrast enhancement than other tumors. Seven of the 15 astrocytomas were hypodense, without calcification and showed contrast enhancement of more than 10 Hounsfield units, whereas this coexistence was not present in any of the 19 tumors of the other histological types.

Adolescent↗

Cerebral blood flow and oxygen consumption during ethanol withdrawal in the rat.

The ethanol withdrawal syndrome in man and animals is characterized by signs of CNS hyperactivity although a direct measurement of a physiological variable reflecting this CNS hyperactivity has never been performed in untreated man or in animals. We induced ethanol dependence in the rat by means of intragastric intubation with a 20% w/v ethanol solution, thus keeping the animals in a state of continuous severe intoxication for 3--4 days; during the subsequent state of withdrawal characterized by tremor, rigidity, stereotyped movements and general seizures a 25% increase in cerebral oxygen consumption (CMRO2) could be measured; this increase was not due to catecholamines originating from adrenal medulla as adrenomedullectomized animals showed a similar increase in CMRO2 (28%); the withdrawing animals showed a corresponding cerebral blood flow (CBF) increase. The elevated CMRO2 and CBF could be reduced to normal by administration of a beta-adrenergic receptor blocker (propranolol 2 mg/kg i.v.), and hence the increased CMRO2 during ethanol withdrawal could be related to catecholaminergic systems in the brain, e.g. the noradrenergic locus coeruleus system which is anatomically well suited as a general activating system. This interpretation is supported by the earlier neurochemical finding of an increased cerebral noradrenaline turnover during ethanol withdrawal. The exact mechanism underlying the increased cerebral oxygen consumption during ethanol withdrawal and the effect of propranolol on cerebral function during this condition remains to be clarified.

Adrenal Glands↗

Comparison of metrizamide and iodophendylate for cerebral ventriculography: a long-term ultrastructural study of the ventricular wall in the rat.

Cerebral ventriculography was performed on adult albino rats to compare the effect of metrizamide and iodophendylate on the ependymal wall. The animals were killed by vascular perfusion 1 month and 4 months after ventriculography. The ependymal layer and the underlying brain tissue were examined with the electron microscope. After the use of metrizamide the tissue appeared completely normal. The use of iodophendylate provoked accumulation of phagocytozing macrophages on the ependymal wall and storage of iodophendylate in the ependyma and underlying brain tissue. These changes were present both 1 and 4 months after ventriculography.

Animals↗

Incidence and long term survival of children with intracranial tumours treated in Denmark 1935-1959.

The total number of children under 15 years of age with intracranial tumours in Denmark during the years 1935-1959 was found to be 533. The average incidence was 21 new cases/10(6) children/year during the 25-year period in question, and 25/10(6) children/year during the first 17 years of Danish cancer registration. The sex ratio (290 boys to 243 girls) was not significantly different from that of the child population in Denmark. In 219 cases the tumour was located in the supratentorial and in 314 in the infratentorial space. 93% of the tumours were histologically verified, with the following order of frequency for the most usual types: astrocytomas (all grades), medulloblastomas, ependymomas, and craniopharyngiomas. Follow-up was 100%. For the 345 children who survived for more than one month after operation or diagnosis, 36% were alive after 15 years. 119 patients were alive in April 1974 and these were all observed between 15-40 years after diagnosis and operation. Of these 44 had tumours in the supratentorial and 75 in the infratentorial space. 66% of the survivors with supratentorial and 90% with infratentorial tumours led a normal life. Most of the survivors had had a cerebellar astrocytoma, a supratentorial astrocytoma, an apendymoma or oligodendroglioma, but other histological diagnoses were also represented, especially in the supratentorial group. The long-term prognosis was especially bad for children with brain-stem tumours, infratentorial ependymomas and medulloblastomas.

Adolescent↗