Biomedical subjects

M Bergmann

Publications and source records attributed to M Bergmann.

At least 145 records · Page 8Linked to original sources

PubMed1993

Ontogeny of synaptophysin and synaptoporin in the central nervous system: differential expression in striatal neurons and their afferents during development.

The expression of the synaptic vesicle antigens synaptophysin (SY) and synaptoporin (SO) was studied in the rat striatum, which contains a nearly homogeneous population of GABAergic neurons. In situ hybridization revealed high levels of SY transcripts in the striatal anlage from embryonic day (E) 14 until birth. In contrast, SO hydridization signals were low, and no immunoreactive cell bodies were detected at these stages of development. At E 14, SY-immunoreactivity was restricted to perikarya. In later prenatal stages of development SY-immunoreactivity appeared in puncta (identified as terminals containing immunostained synaptic vesicles), fibers, thick fiber bundles and 'patches'. In postnatal and adult animals, perikarya of striatal neurons exhibited immunoreaction for SO; ultrastructurally SO antigen was found in the Golgi apparatus and in multivesicular bodies. SO-positive boutons were rare in the striatum. In the neuropil, numerous presynaptic terminals positive for SY were observed. Our data indicate that the expression of synaptic vesicle proteins in GABAergic neurons of the striatum is developmentally regulated. Whereas SY is prevalent during embryonic development, SO is the major synaptic vesicle antigen expressed postnatally by striatal neurons which project to the globus pallidus and the substantia nigra. In contrast synapses of striatal afferents (predominantly from cortex, thalamus and substantia nigra) contain SY.

Animals↗

PubMed1993

Desmoplastic ganglioglioma: report of two non-infantile cases.

Two supratentorial desmoplastic gangliogliomas arising in a 15-year-old boy and a 25-year-old man are reported. Both tumors reached the brain surface and exhibited large cysts. They showed intense desmoplasia and tumor cells of astrocytic and ganglionic differentiation. In one case the ganglionic nature was only demonstrable by immunohistochemistry. Such neoplasms can no longer be regarded as exclusively infantile brain tumors.

Adolescent↗

PubMed1993

Neuropathology of lissencephalies.

The neuropathological findings at autopsy in four cases of type I and three of type II lissencephaly are presented. Type I lissencephaly is characterized by agyriapachygyria with a markedly thickened cerebral cortex with four coarse histological layers. The normally myelinated white matter, often with neuronal heterotopias, is very narrow, and the gray-to-white matter ratio is inverted (about 4:1); there are no white-gray interdigitations. Claustrum and capsula extrema are absent. Ventricular dilatation is present, especially of the occipital horns. In the hypoplastic brain stem large olivary heterotopias can often be observed. Severe cerebellar malformations, obstructive hydrocephalus, severe eye abnormalities, and congenital muscular dystrophy are not seen. Clinically, type I lissencephaly presents as "isolated lissencephaly sequence" or as "Miller-Dieker syndrome" with characteristic facial dysmorphism. The long survival of 20 years achieved by one of our patients is very uncommon. Type II lissencephaly is characterized by widespread agyria. Usually, obstructive hydrocephalus is present with a thin cerebral mantle showing a slightly thickened cortex and a narrow, hypomyelinated white matter often with neuronal heterotopias (gray-to-white matter ratio about 1:1). The border between gray and white matter is blurred. Claustrum and capsula extrema are absent. Histologically, the cortex appears disorganized without layering; widespread leptomeningeal gliomesenchymal proliferations and glioneuronal heterotopias are present.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1993

A probably familial saccular aneurysm of the anterior communicating artery in a neonate.

A 32-day-old boy died of recurring cerebral hemorrhages starting on the 4th day of life. Autopsy disclosed a remittingly ruptured saccular aneurysm of the anterior communicating artery. A 7-day-old brother of his had previously died of recurring subarachnoid hemorrhages as well. The young age of the patient, the site of the aneurysm, and its probably familial occurrence make this case a unique one. Nonaneurysmatic basal cerebral arteries showed remarkable histological changes partly resembling those seen in fibromuscular dysplasia, some of them probably representing preaneurysmatic alterations. A known underlying systemic disease could not be found, and immunohistochemical detection of type III collagen revealed no identifiable deficiency.

Aneurysm, Ruptured↗

PubMed1993

Localization of inhibin/activin subunits in the testis of adult nonhuman primates and men.

The localization and distribution of inhibin/activin subunits was evaluated in the testes of three nonhuman primate species (Macaca fascicularis, M. mulatta, M. arctoides), of young (31 to 43 years) and old (60 to 85 years) men, and of men with disturbed or arrested spermatogenesis using immunohistochemical techniques (peroxidase-anti-peroxidase and alkaline-phosphatase/anti-alkaline-phosphatase technique). Specific polyclonal (anti-porcine inhibin alpha-1-32 and anti-bovine activin A) and monoclonal (anti-human inhibin alpha-1-32 and anti-human activin beta A-82-114) antisera were employed. Among all nonhuman primate species and in men, inhibin/activin subunits were present in the cytoplasm of Sertoli cells and Leydig cells but not in germ cells. No relationship could be established between the staining pattern for inhibin/activin subunits and the completeness or the stage of the spermatogenic process. The staining for the beta A-subunit in Sertoli cells appeared more intense in the testes of old men compared with that of young men. The majority of Leydig cells contained either the alpha-subunit and beta A-subunit or the beta A-subunit alone. The signal for the beta A-subunit was remarkably intense in normal and hyperplastic human Leydig cells. These observations demonstrate the presence of inhibin/activin subunits in Sertoli cells and Leydig cells of adult primates and raise the possibility that these subunits or their respective dimers (inhibin A/activin A) might subserve a paracrine/autocrine role in the adult primate testis.(ABSTRACT TRUNCATED AT 250 WORDS)

Activins↗

PubMed1993

Motor neuron disease with pallido-luysio-nigral atrophy.

A case of motor neuron disease (MND) with pallido-luysio-nigral atrophy (PLNA) is reported. The 45-year-old male patient presented with lower motor neuron symptoms and signs of basal ganglia disturbance. He died after a progressive course of 7 months. Neuropathological examination revealed motor neuron loss at all spinal cord levels with sparing of Onuf's nucleus. Nerve cell loss and gliosis were also present in substantia nigra, globus pallidus, and subthalamic nucleus. The presence of ubiquitin-positive inclusions, a hallmark of most variants of MND, confirms this case as an example of MND. At immunoelectron microscopy the granules were distributed on filamentous material. The combination of clinically apparent PLNA with MND has only been described twice previously. The relationship of this syndrome to other forms of MND and its nosological placement are discussed.

Atrophy↗

PubMed1993

Progressive multifocal leukoencephalopathy (PML) in the acquired immunodeficiency syndrome (AIDS). A neuropathological autopsy study of 21 cases.

In a neuropathological autopsy study of 21 cases of AIDS-associated PML no fundamental morphological differences to non-AIDS PML were found. PML in AIDS often showed very large foci as well as necrotizing lesions. Partial involvement of cerebral cortex and deep gray matter were common findings; infratentorial lesions could be observed in more than three quarters of cases. Perivascular mononuclear infiltrates within PML foci were frequent and obviously not associated with a more benign clinical course. Possible reasons for these peculiarities of PML in AIDS are discussed. In 7 cases evidence of concomitant HIV encephalopathy was found; this may be one relevant factor contributing to severity of PML in AIDS. PML has to be regarded as a common complication of HIV infection, which may show atypical morphological and neuroradiological features.

AIDS-Related Opportunistic Infections↗

PubMed1993

AIDS-myelopathy. A neuropathological study.

Vacuolar myelopathy belongs to the AIDS-associated diseases. It is characterized by vacuolation and infiltration of the long tracts of the spinal cord by macrophages. The clinical and morphological findings of 8 AIDS-patients with vacuolar myelopathy are reported here. The syndrome developed during the final stages of AIDS and was associated with HIV-encephalopathy in 5 cases. The vacuoles were mainly due to intramyelinic swelling and vacuolation. Vacuolated macrophages and axons contributed only to a minor degree. In one case only, HIV-antigens were detected immunohistochemically. The results are discussed in the light of modern pathogenetical concepts of HIV-related diseases.

AIDS Dementia Complex↗

PubMed1993

Non-Hodgkin lymphomas of the central nervous system. Clinico-pathologic and immunohistochemical study of 147 cases.

We report on data gathered from five European centres regarding 147 primary non-Hodgkin Lymphomas (NHLs) of the Central Nervous System (CNS) in HIV-negative patients. The results lead us to make the following considerations: i) there has been a significant and progressive increase in the frequency of observation of this pathology during the course of the last two decades; ii) the pathology lacks specific characteristic symptoms; iii) the radiological profile, as observed by CAT and/or MNR, most frequently corresponds to an isodense or slightly hyperdense lesion which has clear margins and is capable of assuming the contrast medium homogeneously; iv) the tumour most often has a single supratentorial localisation; v) high grade B-cell lymphomas account for 66% of the observations, low grade B-cell varieties being relatively rare and cases of T-cell derivation exceptional (6/147); vi) immunohistochemistry allows the differential diagnoses with respect to primitive or secondary non-lymphoid tumours, and provides confirmation of the histogenetic assessment made on morphological grounds; vii) the course of the disease is not significantly influenced by the histotype, the phenotype, the number of lesions present or the chemotherapy regimen, but rather by the employment of combined surgery and radio- or radiochemotherapy. This study represents the largest series of CNS NHLs so far reported, and as such, provides precise clinico-pathological indications which were only partially obtainable from the relatively small previously published series. Some concluding remarks are made as to the genesis of CNS NHLs, along with some practical suggestions for reaching a better understanding of their complex biology.

Adolescent↗

PubMed1993

Motor neuron disease/amyotrophic lateral sclerosis--lessons from ubiquitin.

Ubiquitin is a stress protein implicated in the degradation of short-lived and abnormal proteins. In a neuropathological study of 43 cases with motor neuron disease/amyotrophic lateral sclerosis (MND/ALS) and 44 control cases the distribution and specificity of Bunina bodies and ubiquitin-reactive inclusions (UBRI) were investigated. The primary motor area showed nerve cell loss in 67%, Bunina bodies in Betz cells (10%) and UBRI in small pyramidal cells (17%). Degeneration of anterior horn cells in all cases coincided with Bunina bodies (84%) and UBRI (98%) in the same location; the motor nuclei of the caudal brain stem were also involved almost to the same degree. More resistant nuclei like the oculomotor nuclei or the Onuf's nucleus showed no degeneration but UBRI in 11% and 18% of cases, respectively. Like the degenerative process, the formation of UBRI was not confined to motor nuclei but also involved the brain stem reticular formation, substantia nigra, and Clarke's nucleus showing that MND/ALS is a multiple system degeneration. UBRI were found in only one control case in the anterior horn cells and in one case in the hypoglossal nucleus showing that UBRI, although not being absolutely specific for MND/ALS, have practical value for the neuropathological diagnosis of that disease. The pathogenetical implications of UBRI in MND/ALS are discussed.

Adult↗

PubMed1993

Immuno-competent cells in the murine epididymis following infection with Escherichia coli.

Epididymitis was induced by retrograde injection of Escherichia coli into the vas deferens of 28 mice. A group of 28 saline-injected animals served as controls. On Days 1, 3, 7 and 28, groups of seven animals were killed. Bacterial culture was performed. Leucocyte numbers and distribution were determined in epididymides. In infected mice, E. coli were isolated from all epididymides on Days 1 and 3, but only from five of seven epididymides on Days 7 and 28. One week after infection, the total number of macrophages rose from about 10 to 28%. Significantly increased macrophage percentages were also found in animals killed 28 days after infection. A simultaneous increase in MHC class II positive cells was seen on Day 7. A total of 20% of the cells expressed MHC class II in infected epididymides (normal = 6%). A similar increase was found on Day 28 after infection. Most of the macrophages and MHC class II positive cells were located in the interstitium, fewer in the peritubular layer and nearly none in the epithelium. The main increase in these cells occurred in the interstitium and, to a lesser but significant extent, in the peritubular area. T-helper and T-suppressor/cytotoxic lymphocytes reached peak values on Day 28. The increase in T-lymphocytes and simultaneous appearance of plasma cells followed the increase in numbers of macrophages and MHC class II positive cells. They were located mainly in the interstitium. A sequential increase in leucocyte subsets and negative culture results for E. coli were observed on Days 7 and 28 (2/7 on each day). The inflammatory process was restricted to the interstitium.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1993

Cellular changes in the cerebellar granular layer in AIDS-associated PML.

Six cases of AIDS-associated progressive multifocal leukoencephalopathy (PML) exhibited peculiar cellular changes in the cerebellar granular layer. These cells without discernible cytoplasm showed hypochromatic nuclei about twice as large as those of normal granule cells. They were restricted exclusively to the granular layer and always surrounded PML foci. An astrocytic, leukocytic or macrophage/microglial nature was largely excluded by immunocytochemistry. Human immunodeficiency virus (HIV) antigen p 24 could not be found in these cells and there was no unequivocal detection of JC virus (JCV) DNA and no ultrastructural evidence of papovavirus particles in them. They possibly represent altered cerebellar granule cells abortively or latently infected with JCV.

Acquired Immunodeficiency Syndrome↗

PubMed1993

Monoclonal antibody MS-44B reacts with human dendritic, glial and endothelial cells: differential expression of MS-44B antigen by epidermal dendritic cells and by MS-1+ splenic sinusoidal endothelial cells. An immunohistological study.

Rat monoclonal antibody MS-44B was raised against the dendritic human melanoma cell line SK-Mel 25 and detects highly dendritic cells and endothelial cells in various human organs. Among the cells recognized are dendritic cells in lymphoid organs, such as lymph node, tonsil and spleen, dendritic cells in skin, lung and lamina propria, (astro-)glial cells in the central nervous system and mesangial cells in the kidney. In peripheral lymph nodes (and less consistently in visceral lymph nodes), MS-44B reactive cells are found predominantly in the paracortical area and in the region of the marginal sinus; in tonsils these dendritic cells are concentrated at the outer rim of the follicle, while their distribution in the white pulp of the spleen is less well defined. In skin, both dermal and epidermal dendritic cells are stained. In the dermis just beneath the dermal-epidermal border, dendritic cells may be found with their processes protruding into the epidermal basal layer. MS-44B reactive epidermal dendritic cells send their processes in a horizontal direction or into the upper epidermal cell layers. MS-44B reactive epidermal dendritic cells are neither Langerhans cells, since they lack HLA-DR antigens and CD1, nor Merkel cells, since they lack cytokeratin expression. They rather seem to constitute a subpopulation of epidermal melanocytes that are low in tyrosinase expression and do not populate the melanocyte area of the hair bulb. With regard to the endothelium, monoclonal antibody MS-44B reveals marked heterogeneity in that it preferentially stains the endothelium of large and medium-sized arterial vessels, while capillary and venous endothelia are less well stained.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1993

Change in location and processing of inhibin alpha-subunit precursors during sexual maturation of the Djungarian hamster testis.

Immunohistochemical location and immunoblot of inhibin alpha-subunit peptides were analyzed in the testis of the Djungarian hamster from days 0-31 of postnatal development using a specific antibody. An intense immunoreaction was observed in the centrally located T1 prespermatogonia at day 0. The staining intensity decreased gradually in the spermatogonia when they make contact with the basal lamina at days 8-10. At days 13 and 15 there is no staining. Thereafter the immunoreactivity in Sertoli cells as well as in A spermatogonia gradually increased, being highest in sexually mature animals. The intensity of alpha-subunit staining in the seminiferous tubules was stage specific, being strongest at stages III and IV. Immunoblot analysis of testis homogenates with the anti-INH alpha 1-32 antibody showed several bands: 88K, 80K, and 43K in immature hamster testis (0-, 2-, 6-, 8-, or 10-day-old). In the adult hamster (31-day-old) 88K, 80K, 28K, and 20K bands were seen, but no 43K band. Dimeric inhibin was not detected. The 43-44K band most likely corresponds to the pro-alpha N alpha C, the 28K band to intermediate forms between alpha N alpha C and alpha C (alpha I alpha C), and the 20K band to mature alpha-subunit (alpha C). The shift from the immature pattern to mature occurs at about 20 days of age. Freezing of the samples was deleterious to alpha C, since it could be detected only in freshly homogenized samples. The results suggest that prespermatogonia produce predominantly monomeric alpha-subunit precursor pro-alpha N alpha C, whereas the mature Sertoli cells as well as A spermatogonia contain mainly monomeric alpha I alpha C. The alpha-inhibin precursors may act as auto-/paracrine regulators of spermatogenesis. Our results suggest that different alpha-subunit precursors, pro-alpha N alpha C and alpha I alpha C, might be involved in the differentiation and maintenance of spermatogenesis, respectively. The posttranslational processing of alpha-subunit precursors seems to play an important role in the physiology of reproduction.

Aging↗

PubMed1993

Primary non-Hodgkin lymphomas of the CNS. Classification, tissue reaction and proliferative activity.

Primary cerebral lymphomas (PCL) are rare tumors, which, however, occur at increasing frequency. From 1980 to 1991, 44 PCL were histologically diagnosed from immunocompetent patients in our department. According to the updated Kiel Classification, 13.5% of the tumors were of low malignancy (4 immunocytomas, 2 centroblastic-centrocytic), and 79.5% were highly malignant B-cell lymphomas (26 centroblastic, 2 Burkitt-type, 3 immunoblastic, 4 unclassified). Two T-cell lymphomas and one large-cell anaplastic lymphoma were found as well. A reactive tissue infiltrate consisting of varying amounts of small T-cells and tissue macrophages was present in all B-cell lymphomas. PCNA-indices reflected the histological grade, with mean counts of 19.5% in low grade neoplasms and 59.3% in high grade ones. No correlation was found to exist between PCNA-index and patient survival.

Antigens, CD↗

PubMed1993

[Primary intracerebral non-Hodgkin's lymphoma--a clinicopathologic study].

Primary cerebral lymphomas (PCL) were diagnosed with increasing frequency also in our retrospective study of 44 patients. Clinically these tumors presented with signs of a rapidly growing brain neoplasm. The analysis of CCT data showed that the tumors were of varying density before and showed mostly (60%) homogeneous enhancement after contrast medium application. MR imaging was more sensitive, but could not aid in distinguishing PCL from other brain tumors. The lesions lay mainly (82%) in the supratentorial space and involved the frontal lobe in 42% of cases. Only 16% were located in the periventricular region including corpus callosum and basal ganglia. 20% of cases showed multiple lesions. Suspected diagnoses were therefore mainly meningeoma, glioma and metastases. Morphological diagnosis was easily possible with the aid of immunohistological methods: there were 41 B-cell lymphomas (93%), two T-cell lymphomas and one large cell anaplastic lymphoma of the non-B non-T phenotype. An unequivocal correlation between morphology and radiological picture existed in the way that tumors with a dense cellular infiltrate appeared mainly as hyperdense lesions with homogeneous contrast enhancement. The clinical course was characterized by CNS-relapses frequently with multiple cerebral lesions and a spinal recurrence in one case. 7% of cases showed evidence of extracerebral disease in a bone marrow biopsy specimen or at autopsy. The average survival of the patients was 15 months, one year survival was 36%, two year survival 12% and 5% of patients lived for more than 5 years.

Adult↗

PubMed1993

[Schizophreniform psychosis in paraneoplastic limbic encephalitis].

Paraneoplastic limbic encephalitis is seldom mentioned in the psychiatric literature and premortem diagnosis is rare. Affective symptoms, agitation, and memory impairment are the core features, which can predate the diagnosis of carcinoma. We report the case of a patient with bronchial carcinoma, whose clinical picture could hardly be distinguished from that of endogenous schizophrenia.

Adult↗

PubMed1992

Sulfhydryl oxidase immunoreactivity in seminiferous tubules of infertile men.

Sulfhydryl oxidase (SOx) immunoreactivity was investigated in the seminiferous epithelium of human biopsy material from the testes of 33 adult men with disturbed fertility. SOx immunoreactivity was expressed in normal seminiferous epithelium in type-A spermatogonia (27 +/- 4% of all spermatogonia) (n = 4), in spermatocytes and round spermatids. Mature spermatozoa as well as Sertoli cells were unlabelled. Within the interstitium, Leydig cells were immunopositive. In biopsies of oligozoospermic men showing hypospermatogenesis (n = 24), an increase in labelled spermatogonia up to more than 90% was observed in biopsies, where seminiferous epithelia revealed only spermatogonia and Sertoli cells. Within the group of oligozoospermic patients there was a significant increase of labelled spermatogonia from 43 +/- 13% (greater than 20 mill/ejaculate) (n = 7) to 55 +/- 16% (less than 20 and greater than 10 mill/ejaculate) (n = 6) to 68 +/- 8% (less than 5 mill/ejaculate) (n = 11) and a significant (P = 0.01) decrease of score count from 7.0 +/- 2.7 to 2.0 +/- 1.8. In this group the increase of labelled spermatogonia was correlated with sperm concentrations in the ejaculate (correlation coefficient: r = -0.6). In biopsies of azoospermic patients showing maturation arrest at the level of spermatocytes or spermatids (n = 5) the percentage of labelled spermatogonia was within the range of 24% to 59%.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗