Biomedical subjects

J Bohl

Publications and source records attributed to J Bohl.

119 records · Page 7Linked to original sources

PubMedDate not supplied

Unbiased estimation of neuronal numbers in the human nucleus coeruleus during aging.

The total number of the neuromelanin-containing neurons of the nucleus coeruleus was determined by means of a newly developed unbiased stereological counting scheme and a low-cost apparative set-up. The individuals (n = 20, age from 49-98 years) included in this study were carefully examined for absence of neurological or psychiatric disorders. However, minor Alzheimer's disease-related neurofibrillary changes occurred in some of the individuals of higher age and these changes were staged. The mean number of neurons per side of the nucleus coeruleus was 15,731 +/- 3,408 SD with a range from 11,737 to 25,319. In three individuals, we compared the left and right nuclei and did not observe significant side differences between the numbers of neurons. There was no correlation between the age of the individuals and the cell number. Also, no correlation was detected between the cell number and the staged occurrence of minor neurofibrillary changes of the Alzheimer type. Due to the novel counting method, the determination of the total cell number took less than 2 h per case.

Age Factors↗

PubMedDate not supplied

Spatial, temporal and numeric analysis of Alzheimer changes in the nucleus coeruleus.

The distribution of neurofibrillary tangles in the nucleus coeruleus was topographically and quantitatively analyzed. The topographical analysis showed statistically significant differences with regard to the distribution of neurofibrillary tangles in the dorsal-ventral and medial-lateral axes. More neurofibrillary tangles were found to be located in the dorsal and medial regions than in ventral and lateral areas. No significant difference in neurofibrillary tangle content was found between the rostral and the caudal areas of the nucleus coeruleus. Neurofibrillary tangle formation begins in the central parts of the nucleus coeruleus. The total number of neuromelanized neurons in the nucleus coeruleus was determined using a modern, unbiased sampling scheme and related to the cortical stage of Alzheimer's disease-related neurofibrillary changes present. A statistically significant reduction (50%) in nucleus coeruleus neurons was evident only in cases meeting the histopathological criteria for Alzheimer's disease. The extent of reduction in the total number of neurons in the nucleus coeruleus did not correlate with the number of neurofibrillary tangles observed. Our data suggest that despite the relatively early susceptibility of the nucleus coeruleus to neurofibrillary tangle formation, significant neuronal loss appears to occur much later, with an estimated average delay time of at least 25 years. Nonetheless, comparison of the topographical pattern of neurofibrillary tangle formation and cell loss indicates that neuronal loss is tangle-related.

Age Factors↗

PubMedDate not supplied

Decrease in adenylate cyclase activity antecedes neurofibrillary tangle formation.

In previous studies, the formation of cAMP was seen to be significantly reduced in various brain regions in Alzheimer patients. Recently, a staging system was introduced in which Alzheimer-related. histopathological changes were classified according to the pattern of alterations rather than their density. In this study, we examined the degree of correlation between these stages and the postmortem activity of the CAMP-generating enzyme adenylate cyclase. Our findings suggest that forskolin-stimulated adenylate cyclase activity is significantly decreased before major neurofibrillary changes develop. Early impairment of postreceptor signalling could have potentially important consequences for drug treatment and/or for the development of neurofibrillary changes.

Adenylyl Cyclases↗

PubMedDate not supplied

[Fatal outcome during physiotherapy (Vojta's method) in a 3-month old infant. Case report and comments on manual therapy in children].

Detailed clinical and neuropathological report on a fatal incident during the first manual therapy according to Vojta conducted in a 3 months old baby: during forced active rotation and head retraction the baby suffered from a bleeding into the adventitia of both her vertebral arteries at the level of C1 prompting ischemia of the caudal brainstem with subarachnoid haemorrhage around. It has to be suggested that similar cases already have occurred but have not been reported yet. There might be a time lag between the performance of physiotherapy and the beginning of neurologic symptoms. The risks of manual therapy in children will be discussed.

Brain Stem Hemorrhage, Traumatic↗

PubMedDate not supplied

[Treatment of an extraneural metastasized medulloblastoma].

We report a patient with a history of a previously treated medulloblastoma, now presenting with generalized osseous metastases. Currently there is a complete remission under continuous therapy with VP-16. Since the frequency of systemic metastases in patients with medulloblastoma is approximately 5%, we recommend a more extensive initial evaluation in these patients.

Adult↗

PubMedDate not supplied

[Evaluating the risk of sciatic nerve damage in the rabbit by administration of low and intermediate energy extracorporeal shock waves].

AIM: The aim of the study was to evaluate the likeliness for peripheral nerve lesions following extracorporeal shock wave application. MATERIAL AND METHOD: 82 rabbit sciatic nerves were randomized to undergo low-energetic (0.08 mJ/mm2), middle-energetic (0.28 mJ/mm2) or no (controls) shock wave therapy. After 1 to 28 days an independent neuropathologist checked the specimen for signs of neural lesions. RESULTS: Only after 14 and 28 days vacuolic swelling of the axons was noted, somewhat pronounced in the middle-energetic group. In no case was there any disruption of the nerve's continuity. We did not observe any neurapraxia. CONCLUSION: Shock wave application does not threaten peripheral nerve integrity in an animal model.

Animals↗

PubMedDate not supplied

Reduced intraneuronal lipofuscin content in dementia with Lewy bodies compared with Alzheimer's disease and controls.

Lipofuscin has been of interest in dementia of Alzheimer's type (DAT), because of the hypothesis that dementia is a kind of premature ageing. The results of studies on intraneuronal lipofuscin content in DAT are inconsistent. At present no data on intraneuronal lipofuscin in dementia with Lewy bodies (DLB) are available. The amount of lipofuscin in the neurons of the inferior olivary nucleus of 10 brains of DLB patients, 10 of age-matched DAT patients, and 10 of age-matched controls has been measured microfluorometrically. The intraneuronal lipofuscin content in the DLB patients was significantly lower than in the DAT patients and controls. This finding may indicate a general alteration of neuronal cell metabolism in DLB, e.g. a defect of mitochondrial DNA, not confined to neurons developing Lewy bodies.

Aged↗

PubMedDate not supplied

The lipofuscin content of nerve cells of the inferior olivary nucleus in Alzheimer's disease.

Lipofuscin, the age pigment, is of interest in Alzheimer's disease because of its property to accumulate in neurons and because of the hypothesis that Alzheimer's dementia is a kind of premature ageing. The amount of intraneuronal lipofuscin in the inferior olivary nucleus of 20 brains from patients with histologically confirmed Alzheimer's disease according to the CERAD protocol and of 20 controls has been measured microfluorometrically. Patients and controls were matched for age. The amount of lipofuscin in the neurons of the inferior olivary nucleus did not differ significantly between the cases of Alzheimer's disease and the controls. The result is discussed taking the findings of previous authors into account. We conclude that there is no evidence that lipofuscin plays an important role in the pathogenesis of Alzheimer's disease.

Aged↗

PubMedDate not supplied

Colocalization of different types of amyloid in the walls of cerebral blood vessels of patients suffering from cerebral amyloid angiopathy and spontaneous intracranial hemorrhage: a report of 5 cases.

Four cases of spontaneous intracranial hemorrhage (ICH) are described in which the diagnosis of a cerebral amyloid angiopathy (CAA) was made in the biopsy specimens. In one further case CAA was detected on autopsy after intracranial hemorrhage (ICH). Amyloidotic degeneration of the vessel walls appeared to be the most likely reason for the ICH which in these cases especially involved superficial neocortical regions. In all cases, co-deposition of A4beta-amyloid and ALlambda-amyloid was found in diseased leptomeningeal and cortical vessels. Besides CAA, all 5 patients suffered from other diseases which had affected the blood vessel walls such as atherosclerosis, diabetes mellitus or arterial hypertension. However, no signs of systemic amyloidosis could be detected in these cases. It is suggested that the observed co-deposition of 2 amyloid subtypes is based on the combination of 2 different diseases, one of which results in a local production of A4beta-amyloid in the tunica media of cerebral blood vessels and another one, e.g. arterial hypertension, which impairs the permeability of the blood vessels by affection of the tunica intima allowing for the pathological penetration of circulating immunoglobulin lambda-light chains into the vessel wall. Subsequently, the preexisting A4beta-amyloid might have induced the polymerization of the lambda-light chains to ALlambda-amyloid in the media of the vessels and could have aggravated the amyloidotic degeneration of the vessel walls.

Adult↗

PubMedDate not supplied

Immunohistochemistry of amyloid-related neuropathies.

Studying eight sural nerve biopsy specimens of a biopsied trigeminal ganglions and peripheral nerves from eight autopsies, some of them retrieved 30 years ago, with a panel of antibodies against several types of amyloid revealed the presence of AF, AL of the lambda type, AA and ASs in peripheral nerve specimens while AB, AE, ASc, ASb, ACc, APrP could not be detected. Amyloid of the AF type in the endoneurial space was associated with loss of unmyelinated and small caliber myelinated axons. Availability of antibodies against respective types of amyloid enables retrospective identification of subtypes of amyloid and aids in further investigation and treatment of patients and their families. Thus, immunohistochemical analysis in peripheral nerve specimens is recommended when amyloid is apparent.

Adult↗

PubMedDate not supplied

Dyke Postmortem CT and Award. autopsy in perinatal intracranial hemorrhage.

To improve interpretation of intracranial computed tomographic findings in vivo, postmortem computed tomography was correlated directly with autopsy findings in 105 specimens of human stillborn and live-birth infants, ranging in age from gestational week 13 to postnatal month 18. This study identifies the typical computed tomographic appearance of intradural and other hemorrhages, attempts to correlate the type of hemorrhage with brain maturity, and documents that postmortem computed tomography is useful to the neuropathologist as a supplementary method complementing the traditional postmortem examination.

Brain↗