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T L Kemper

Publications and source records attributed to T L Kemper.

At least 37 records · Page 2Linked to original sources
PubMed1985

Coffin-Siris syndrome. Neuropathologic findings.

We studied the neuropathologic features of a patient with Coffin-Siris syndrome. Two previously reported cases showed Dandy-Walker (D-W) malformations. In the present case there was no evidence of D-W malformation; instead there were hindbrain abnormalities of inferior and medial accessory olives, large arcuate nuclei, heterotopic olivary nuclei, and heterotopic nuclei in the white matter of the cerebellum. Although the hindbrain abnormalities in this case are different from those previously reported, they all have in common an intimate developmental relationship with the same embryological areas. This study suggests that the Coffin-Siris syndrome is a neurocutaneous disorder with hindbrain abnormalities in cerebellum and brain stem.

Abnormalities, Multiple↗
PubMed1985

The effects of protein deprivation on neuronal migration in rats.

Although there is extensive literature documenting the effects of undernutrition on brain development, most studies have been concerned with cell differentiation with little attention given to neuronal migration. In a rat model we have investigated the effect of chronic protein deprivation on cell migration from the anterior lateral ventricle to the olfactory bulb. By using standard autoradiographic techniques and comparing the position of heavily labeled cells within the migratory stream, we estimated the migration rate to be 100 microns/h in 25%-casein-diet rats and between 33 and 70 microns/h in 8%-casein-diet rats. We therefore conclude that migration is slowed in chronically protein-deprived rats and this slowed migration may be related to subsequent abnormalities of cell differentiation seen in protein-deprived rats.

Animals↗
PubMed1985

Histoanatomic observations of the brain in early infantile autism.

Early infantile autism is a behaviorally defined syndrome that is often associated with abnormalities on neurologic examination and seizures. We report on the brain of a 29-year-old autistic man as compared with that of an age- and sex-matched normal control, using gapless sections of whole brain. Abnormalities were found in the hippocampus, subiculum, entorhinal cortex, septal nuclei, mamillary body, selected nuclei of the amygdala, neocerebellar cortex, roof nuclei of the cerebellum, and inferior olivary nucleus.

Adult↗
PubMed1985

Anatomical basis of learning disabilities. Brain specialization.

The brains of all three patients with developmental dyslexia studied thus far have shown scattered small malformations primarily in the cerebral cortex of the left cerebral hemisphere. The available evidence on the pathogenesis of these lesions suggests that they are the result of a destructive process occurring during the latter part of the first half of pregnancy.

Adolescent↗
PubMed1984

Down's syndrome: is there a decreased population of neurons?

Although gross abnormalities have been described in the brains of patients with Down's syndrome (DS), microscopic studies have revealed only minor and inconsistent findings. We compared two DS brains, in whole-brain serial sections, with similarly prepared age- and sex-matched normal controls. Architectonic abnormalities were noted, and cell counts revealed a significant poverty of granular cells in the DS brains, particularly in granular fields such as areas 3, 17, and 41. Golgi studies demonstrated all major cell types. A striking feature of the brain morphology in DS may be the curtailment of a specific cell type, most likely the aspinous stellate.

Adult↗
PubMed1982

Pathogenesis of four-layered microgyric cortex in man.

Microgyria (polygria, polymicrogyria) has stimulated continued interest since its first description by Meschede [28]. Based on analysis of case material, available staining techniques, and known principles of human cortical development, subsequent investigators have proposed numerous theories to explain its pathogenesis. We have studied a case which cannot be fully explained by these previously proposed theories. In this case, four-layered microgyria is present bilaterally in middle cerebral artery distribution, but in one hemisphere, in the center of the malformed area, the deep acellular and cellular layers are replaced by radially aligned neurons extending ectopically into prospective white matter. Analysis of the findings in this case provide evidence that the recently described pathogenetic mechanism observed in a rat model of this malformation [15,16] is applicable to its formation in man.

Animals↗
PubMed1982

Morphologic and histoanatomic observations of the brain in untreated human phenylketonuria.

The cerebra of three profoundly retarded adult males with untreated phenylketonuria (PKU) were systematically studied in terms of developmental morphology and histoanatomy against normal age-matched material, technically comparable in preparation. These studies were made possible by the availability of two extensive reference collections of normative neuroanatomic material, the Yakovlev and the Conel collections. The developmental parameters of myelination, width of the cortical plate, cell packing density, neuronal cell size, development of Nissl granulation, dendritic arborization and synaptic spine populations were studied. Our results indicate that there is a marked curtailment of histoanatomical maturation of the brain in PKU by all developmental parameters studied.

Adult↗
PubMed1982

Senile cerebral amyloid. Prealbumin as a common constituent in the neuritic plaque, in the neurofibrillary tangle, and in the microangiopathic lesion.

Three lesions that characterize the nosologic findings in the brain of Alzheimer's presenile dementia and senile dementia of Alzheimer type, ie, neuritic plaque, neurofibrillary tangle, and microangiopathy, all are frequently associated with amyloid deposition. There has been some question, however, as to whether these lesions share the same etiology. Moreover, the specific chemical nature of amyloid associated with these lesions has not yet been determined. In the present study, formalin-fixed paraffin sections of the affected brains were tested immunocytochemically for their reactivity against antiserum to prealbumin (recently disclosed as the major constituent of amyloid associated with familial amyloidotic polyneuropathy as well as senile cardiac amyloid) and known components of other types of amyloid (AA, AP, etc.). The results demonstrated that amyloid deposits in all three lesions reacted with anti-prealbumin, suggesting that it is a common constituent of these lesions. Indeed, it is likely that prealbumin is the major constituent of amyloid associated with neuritic plaque, neurofibrillary tangle, and microangiopathy.

Alzheimer Disease↗
PubMed1980

Amygdaloid changes in aging and dementia.

A quantitative and clincally correlated investigation was carried out to determine the divisional distribution of volumetric and cell-packing density changes in the amygdala in patients with advanced aging and senile dementia. Normal controls show relatively little, but nevertheless significant, age-related change. In contrast, the amygdala undergoes very marked degeneration in patients with senile dementia, which preferentially affects the morphologcially, developmentally, and connectionally older medial, medial central, and cortical nuclei. These findings strengthen the possibility that the amygdala participates in the behavioral changes that occur in senile dementia.

Adult↗
PubMed1978

Right-left asymmetrics in the brain.

Structural asymmetries between the hemispheres are found in the human brain. Asymmetries in the auditory regions and in the Sylvian fissures are present even in the fetus. The Sylvian asymmetries may have existed in Neanderthal man and are found consistently in some apes. They may relate to right-left differences infunction. Thus, the striking auditory asymmetries could underlie language lateralization. The asymmetries in the frontal and occipital lobes and the lateral ventricles are correlated with hand preference. Anatomical asymmetries may help to explain the range of human talents, recovery from acquired disorders of language function, certain childhood learning disabilities, some dementing illnesses of middle life, and the evidence for behavioral lateralization in nonhuman primates.

Animals↗
PubMed1977

Effects of single dose supervoltage whole brain radiation in Macaca mulatta.

Three groups of four Macaca mulatta were exposed respectively to a single dose of 1000, 1500, and 2000 rads of 20 MeV whole brain radiation with one animal from each group and a control scheduled for sacrifice at 6, 12, 18, and 24 months. With 1000 rads there were no abnormalities. The characteristic lesions in the animals exposed to 1500 and 2000 rads were small foci of delayed radiation necrosis that in the acute phase were relatively large due to marked local accumulation of edema fluid and at later stages were decreased in volume and showed early mineralization. Correspondingly the monkeys frequently showed papilledema, evidently from brain swelling, as the initial clinical finding, and upon histological examination at later stages, brain atrophy and ventricular dilatation. After exposure to 1500 rads the necrotic process was primarily in the white matter of the cerebral hemisphere and progressed from a small number of lesions in this location at 6 months to confluent necrosis at 12 months. At 18 and 24 months, although there was no evidence of further necrosis, there was evidence of increasing gliosis and at 24 months the occurrence of three independent glioblastomas. With exposure to 2000 rads there was a profuse wide scatter of focal necrotic lesions with a predilection for the basis pontis and a clinical deficit inconsistent with survival past 6 months. Accumulation of minute mineral deposits and atherosclerotic plaques were also noted in these monkeys and appeared to be related to both dose and survival time.

Animals↗