Hirano body-rich subtypes of Creutzfeldt-Jakob disease.

BACKGROUND: In definite Creutzfeldt-Jakob disease (CJD), morphological and immunohistochemical patterns are useful to identify molecular subtypes. Severe cerebellar pathology and hippocampal involvement helps to identify VV subtypes. The rare VV1 variant (<1%), more frequent in young individuals, is additionally characterized by the presence of ballooned neurones in affected areas. In 1985, Cartier et al. described a family cluster of three individuals with an ataxic CJD form, showing, in addition to severe cerebellar and hippocampal involvement, the presence of frequent Hirano bodies (HB) in CA1 pyramidal neurones. HB are frequently found in aged individuals with Alzheimer pathology although they are not a specific finding. AIMS AND METHODS: In this study, we evaluated the presence of HB in hippocampi of 54 genetically and molecularly characterized CJD cases, aiming to elucidate whether additional morphological features could be helpful to point to molecular subtypes. RESULTS: We identified nine cases (four VV1, one out of three MV2K, three out of six MV2K+2C and one MV carrying a 96-base pair insertion) with abundant, partly bizarre and clustered HB in CA1 sector, not observed in other subtypes. The presence of HB was independent of hippocampal involvement by the disease itself. CONCLUSIONS: Clusters of abundant HB might be found in rare CJD subtypes such as VV1, MV2K/MV2K+2C and some genetic cases. In addition to histopathological and PrP immunohistochemical deposition patterns, their presence might be a useful additional morphologic feature that could point to the molecular subtype, especially when genetic and/or Western blot analyses are not available.

Distribution of polycyclic aromatic hydrocarbons in riverine waters after Mediterranean forest fires.

Extensive forest fires occurred in Catalonia, northern Spain, in 1994. In our study, concentrations and profiles of 12 parent polycyclic aromatic hydrocarbons (PAHs) were determined in riverine waters, ash and sediment samples at nine sampling sites (W1-W9) and at three sampling dates from Llobregat hydrographic basin: in August, 1994, one month after the extensive forest fires; in September, 1994, after the first heavy autumn rainfalls and in January, 1995, six months after forest fires. In August 1994, the total concentrations of 12 PAHs measured in riverine waters varied from 2 ng/l to 336 ng/l. In September 1994, the total PAH concentrations decreased to 0.2-31 ng/l and in January 1995, from 9 ng/l to 73 ng/l. In August, the composition pattern of PAHs showed a distribution dominated by 4-ring PAHs (pyrene, chrysene+triphenylene, benzo(a)anthracene) at W3-W6, W8 and W9 and 3-ring PAHs (phenanthrene) at W1, W2 and W7. In September, a preference by 3-ring PAHs (phenanthrene) at all sampling sites except W5 was shown and in January was clearly dominated by 4-ring PAHs (chrysene+triphenylene, pyrene, benzo(a)anthracene) at all sampling sites. In ash and sediment samples, the total concentrations of 12 PAHs ranged from 1.3 ng/g to 19 ng/g. The dominant compound was phenanthrene.

BDNF and full-length and truncated TrkB expression in Alzheimer disease. Implications in therapeutic strategies.

Brain-derived neurotrophic factor (BDNF), and full-length and truncated tyrosin kinase B receptor (TrkB) protein expression were examined by Western blotting and immunohistochemistry in the frontal cortex and hippocampus of individuals affected by long-lasting severe Alzheimer disease (AD) and age-matched controls. Since preliminary processing studies in the brains of rats have shown loss of immunoreactivity depending on the postmortem delay in tissue processing and on the type, duration, and temperature of the fixative solution, only human samples obtained up to 6 hours (h) after death for biochemical and morphological studies and fixed by immersion in 4% paraformaldehyde for 24 h for morphological studies were included in the present series. Decreased BDNF and full-length TrkB expression accompanied by increased truncated TrkB expression, as revealed by Western blotting, was observed in the frontal cortex of patients with AD. Immunohistochemistry disclosed reduced BDNF and full-length TrkB immunoreactivity in neurons. BDNF decrease was equally observed in tangle-bearing and non-tangle-bearing neurons, as revealed with double-labeling immunohistochemistry to BDNF and phosphorylated tau or phosphorylated neurofilament epitopes. Full-length TrkB immunoreactivity was largely decreased in tangle-bearing neurons, whereas only moderate decreases occurred in neurons with granulovacuolar degeneration. Strong BDNF immunoreactivity was observed in dystrophic neurites surrounding senile plaques, whereas strong TrkB expression occurred in reactive glial cells, including those surrounding senile plaques. Finally, truncated TrkB immunoreactivity was observed in individual neurons and in reactive glial cells in the cerebral cortex and white matter in AD. These results show decay in the expression of BDNF and TrkB in AD neurons, accompanied by altered BDNF, and full-length and truncated TrkB expression in dystrophic neurites and reactive glial cells, respectively, in this disease. The present results demonstrate selective decline of the BDNF/TrkB neurotrophic signaling pathway in the frontal cortex and hippocampus in AD and provide supplemental data that may be relevant in discussing the suitability of the use of BDNF as a therapeutic agent in patients with AD.

Phosphorylated map kinase (ERK1, ERK2) expression is associated with early tau deposition in neurones and glial cells, but not with increased nuclear DNA vulnerability and cell death, in Alzheimer disease, Pick's disease, progressive supranuclear palsy and corticobasal degeneration.

Abnormal tau phosphorylation and deposition in neurones and glial cells is one of the major features in taupathies. The present study examines the involvement of the Ras/MEK/ERK pathway of tau phosphorylation in Alzheimer disease (AD), Pick's disease (PiD), progressive supranuclear palsy (PSP) and corticobasal degeneration (CBD), by Western blotting, single and double-labelling immunohistochemistry, and p21Ras activation assay. Since this pathway is also activated in several paradigms of cell death and cell survival, activated ERK expression is also analysed with double-labelling immunohistochemistry and in situ end-labelling of nuclear DNA fragmentation to visualise activated ERK in cells with increased nuclear DNA vulnerability. The MEK1 antibody recognises one band of 45 kD that identifies phosphorylation-independent MEK1, whose expression levels are not modified in diseased brains. The ERK antibody recognises one band of 42 kD corresponding to the molecular weight of phosphorylation-independent ERK2; the expression levels, as well as the immunoreactivity of ERK in individual cells, is not changed in AD, PiD, PSP and CBD. The antibody MAPK-P distinguishes two bands of 44 kD and 42 kD that detect phosphorylated ERK1 and ERK2. MAPK-P expression levels, as seen with Western blotting, are markedly increased in AD, PiD, PSP and CBD. Moreover, immunohistochemistry discloses granular precipitates in the cytoplasm of neurones in AD, mainly in a subpopulation of neurones exhibiting early tau deposition, whereas neurones with developed neurofibrillary tangles are less commonly immunostained. MAPK-P also decorates neurones with Pick bodies in PiD, early tau deposition in neurones in PSP and CBD, and cortical achromatic neurones in CBD. In addition, strong MAPK-P immunoreactivity is found in large numbers of tau-positive glial cells in PSP and CBD, as seen with double-labelling immunohistochemistry. Yet no co-localisation of enhanced phosphorylated ERK immunoreactivity and nuclear DNA fragmentation is found in AD, PiD, PSP and CBD. Finally, activated Ras expression levels are increased in AD cases when compared with controls. These results demonstrate increased phosphorylated (active) ERK expression in association with early tau deposition in neurones and glial cells in taupathies, and suggest activated Ras as the upstream activator of the MEK/ERK pathway of tau phosphorylation in AD.

Immunohistochemical analysis of the immune reaction in the nervous system in paraneoplastic encephalomyelitis.

We examined frozen sections of frontal cortex, medulla, and dorsal root ganglia from a patient with small-cell lung cancer and paraneoplastic encephalomyelitis, involving the medulla and dorsal root ganglia, with a panel of antibodies reactive for IgG, IgM, C3, B cells, T cells, T cell subsets, macrophages, and class I and II (HLA-DR) major histocompatibility complex (MHC) antigens. We detected an antineuronal antibody (anti-Hu) in the serum and CSF of the patient and found deposits of IgG in the periphery of some neurons in dorsal root ganglia. The infiltrates were almost exclusively T cells with a predominance of CD8-positive cells. Neurons did not express class I or II MHC antigens. Satellite cells in the dorsal root ganglia from the patient and controls were HLA-DR-positive. These data indicate that CD8-positive T cells predominate in the inflammatory infiltrates of paraneoplastic encephalomyelitis. IgG deposits may be relevant in the damage of the sensory neurons.

Amine oxidase activities in rat breast cancer induced experimentally with 7,12-dimethylbenz(alpha)anthracene.

The activities and distribution of monoamine oxidase (MAO) and semicarbazide-sensitive amine oxidase (SSAO) in solid breast tumour induced in the rat by treatment with 7,12-dimethylbenz(alpha)anthracene (DMBA) were studied. The mammary tumours were classified according to anatomopathological criteria into: the benign fibroadenoma (FAD) and the malignant adenocarcinoma (ADC) and infiltrant adenocarcinoma (I-ADC). The proportions of total MAO (15%) and SSAO activities (85%) did not change with malignancy. However, an increasing degree of malignancy was associated with an increase in MAO-A activity and a decrease in MAO-B and SSAO activities. Kinetic constants were calculated for SSAO and for each MAO form separately, using specific substrates. The Km values did not change significantly with the degree of malignancy, but Vmax values for MAO-A increased whereas Vmax for SSAO and MAO-B diminished with malignancy. The dependence of SSAO activity on protein concentration indicated the presence of endogenous reversible inhibitory material in extracts from the more malign tumours. This inhibitor was associated with the microsomal fraction and was not removed by dialysis. It was also present in detergent-solubilized extracts, suggesting that the phenomenon might be due to an association of the enzyme itself producing an inactive species.

Malignant pigmented clear cell epithelioid tumor of the kidney: clear cell ("sugar") tumor versus malignant melanoma.

A 73-year-old woman presented with an hemorrhagic kidney tumor initially interpreted as a renal cell carcinoma (RCC). A retroperitoneal recurrence infiltrating the duodenal wall was made up of clear cells, some of which contained Fontana-Masson positive pigment, immunopositive for HMB-45, S-100 protein, actin, and vimentin. The same immunohistochemical profile was retrospectively reproduced in the kidney tumor, where melanosomes were also found ultrastructurally. Lipomatous differentiation was not observed. There was no history of malignant melanoma (MM), or stigmata of tuberous sclerosis. The patient died of disease 5 years after the initial diagnosis. This neoplasm can be considered as a malignant, pigmented, clear-cell epithelioid variant of angiomyolipoma, or "sugar" tumor of the kidney, with the peculiarity of having a previously unreported component of pigmented cells visible on light microscopy. This finding raises the possibility that the exceptional cases of MM reported in renal parenchyma may be pigmented variants of epithelioid angiomyolipoma rather than true MM.

Thymoma associated with CD4+ lymphopenia, cytomegalovirus infection, and Kaposi's sarcoma.

A case of thymoma with associated opportunistic infections, CD4/CD8 T-lymphocyte imbalance, low CD4-positive T-lymphocyte counts and Kaposi's sarcoma (KS) without HIV infection is reported. Cytomegalovirus inclusions were identified in the nuclei of some KS spindle and endothelial cells. It is known that KS has a high prevalence in AIDS patients and has occasionally been associated with other causes of immunosuppression. In previous studies, coexisting KS and thymoma were related to myasthenia gravis, corticosteroid treatment and excess CD8-positive T-lymphocyte counts. More recently an imbalance between CD4 and CD8 positive T lymphocytes has been identified in association with thymoma. The present case suggests that there may be a relationship between thymoma, CD4-positive lymphopenia, and KS.

Effects of an androgenic derivative on pre-established mammary tumours chemically induced in the rat.

The effects were studied of an androgenic derivative--danazol--administered at doses of 10-12 mg kg-1 day-1 during 97 days to rats with dimethylbenz[a] anthracene-induced mammary tumours. Our main observations were as follows. (a) Danazol did not influence ovarian function at the end of the assay. (b) The treatment with danazol reduced the incidence (P less than 0.05), number of tumours (P less than 0.05) and volume of malignant mammary tumours; on the other hand, the values of these parameters for benign tumours and those of doubtful expression were similar in both experimental groups. (c) Such differential action of Danazol seems to be due to the different incidence and/or content of receptors of both types of tumours. (d) The latter results lead to a hypothesis for the mechanism of action of danazol based on its behaviour at different levels.

Brain-derived neurotrophic factor in Huntington disease.

Trophic factors, administered systemically or delivered via genetically-modified cells grafted into target regions, have been proposed as putative therapeutic agents in human neurodegenerative disorders. In parallel to the study of the beneficial effects in experimental models of particular diseases, a crucial aspect of the study of trophic factors is the gathering of information about the actual trophic factor expression in human diseased states. Brain-derived neurotrophic factor (BDNF) promotes survival and growth of various nerve cell populations during normal development and following various insults in the developing and adult brain. In particular, BDNF prevents cell death of certain striatal populations in excitotoxic models of Huntington disease (HD) following intrastriatal injection of quinolinic acid to the adult rodent brain. The present study examines BDNF expression, by gel electrophoresis and Western blotting, and immunohistochemistry, in the brains of patients who had suffered from HD. Reduced BDNF expression, ranging from 53 to 82%, has been found in the caudate and putamen in HD when compared with age-matched controls. No modifications in BDNF expression levels have been seen in the parietal cortex, temporal cortex and hippocampus. Furthermore, immunohistochemistry has shown reduced BDNF immunoreactivity in caudate neurons, but not in cortical neurons in HD when compared with controls. These data demonstrate selective BDNF decay in regions that are vulnerable to HD, and suggest, in combination with results in experimental models, that a BDNF surplus may have beneficial effects in the treatment of HD.

Brain-derived neurotrophic factor in patients with frontotemporal dementia.

Brain-derived neurotrophic factor (BDNF) promotes survival and growth of various nerve cell populations during normal development and following different insults in the developing and adult brain. BDNF expression is reduced in Alzheimer disease, but little is known about BDNF expression in other types of dementia. Frontotemporal dementia (FTD) is a common cause of mental impairment in old age, which is characterized by neuron loss in the upper cortical layers mainly of the frontal and temporal cortex. BDNF protein expression has been examined by Western blotting and immunohistochemistry in the cerebral cortex of individuals affected by FTD. Examination of pathological samples (n = 8, mean age: 74.7 years; four men, four women) was conducted in parallel with corresponding samples from age-matched controls (n = 8; mean age: 72.6 years; three men, five women). Post-mortem delay was between 2 and 6 h. Preserved BDNF expression, as revealed by Western blotting, has been observed in the frontal and temporal cortices of patients with FTD. Furthermore, immunohistochemistry has disclosed maintained BDNF immunoreactivity in surviving neurons of the upper cellular layers, as well as in neurons of the inner cellular layers in FTD. These results show that FTD is not associated with a decay of BDNF in cortical neurons, and therefore, that BDNF is differentially regulated in diseases causing dementia.

Expression of lymphocyte, macrophage and class I and II major histocompatibility complex antigens in normal human dorsal root ganglia.

We analyzed the expression of lymphocyte, macrophage and class I and II (HLA-DR) major histocompatibility complex (MHC) antigens in normal dorsal root ganglia (DRG) from 19 patients without neurological disease by using an avidin-biotin immunoperoxidase technique. Satellite cells expressed class I and II MHC antigens. The intensity of HLA-DR staining varied among the DRG and was not related to age, history of cancer or infection, or number of T lymphocytes in the DRG. Monoclonal antibodies EBM11 and Leu-M3, that recognize cells of monocyte/macrophage lineage, stained a population of cells in all DRG. Positive cells had an elongated shape and were in the interstitial tissue between the satellite cells. These findings may be relevant to the understanding of the immune mechanisms involved in the neuronal damage of sensory neuropathies of presumably autoimmune origin such as those associated with small-cell lung cancer or Sjögren's syndrome.

Effect of intraventricular injection of an anti-Purkinje cell antibody (anti-Yo) in a guinea pig model.

Female guinea pigs had intraventricular injections of either IgG from a patient with paraneoplastic cerebellar degeneration (PCD) and anti-Purkinje cell antibodies (anti-Yo IgG) or control IgG. In animals that received a single injection of control or anti-Yo IgG and were killed at different time intervals, IgG immunoreactivity was present in the cytoplasm of Purkinje cells at 2 h and persisted at 24 h. In guinea pigs injected for 15 days with control or anti-Yo IgG and sacrificed 24 h after the last injection, IgG was detected into the Purkinje cells in both groups, whereas animals killed 7 and 30 days after the last injection had no staining for IgG in the Purkinje cells. Clinical or pathologic evidence of cerebellar involvement was not seen in any of the animals. This study suggests that anti-Yo antibody alone may not be the cause of the Purkinje cell loss in PCD.

Intranuclear inclusions, neuronal loss and CAG mosaicism in two patients with Machado-Joseph disease.

UNLABELLED: The presence of neuronal intranuclear inclusions (NIIs) and neuronal mosaicism has been described in some autosomal dominant spinocerebellar ataxias (SCA), but their implication in neurodegenerative mechanisms still remains unclear. OBJECTIVE: To investigate the correlation between neuronal loss and NIIs, and the size of CAG triplet expansion in selected areas of the CNS in two SCA3 patients. MATERIAL AND METHODS: Postmortem neuropathological study was carried out, and the regional distribution of neuronal loss was compared with NIIs. CAG expansion was analysed by PCR amplification in the same regions. RESULTS: Marked neuronal loss was seen in the anterior horn of the spinal cord, pontine nuclei and motor nuclei of the brain stem. Moderate neurone loss was found in the locus ceruleus, colliculus and substantia nigra. Loss of granule and Purkinje cells was found in the cerebellum, mainly in the vermis. NIIs were present in neurones of the involved nuclei of the anterior horn of the spinal cord, medulla oblongata and pons, but not in the locus ceruleus, substantia nigra and cerebellum. A few NIIs were found in the striatum. The number of CAG repeats was 27/70 in the first patient and 21/74 in the second patient. The variation of the expanded allele size among different cerebral areas was +/-1-3 CAG repeats. CONCLUSION: The partial correlation between neuronal loss and NIIs suggests that other factors distinct from NII formation may be involved in the neuronal death. Moreover, the low degree of mosaicism between regions without neuronal loss and regions with marked neuronal loss points to the existence of selective cellular vulnerability to the genetic defect.

Tuberous sclerosis: a Golgi study of cortical tuber.

The cytoarchitecture and fine structure of seven cortical tubera were studied by means of camera lucida drawings and Golgi sections in the coronal, sagittal, and tangential planes. Varied structural disorganization was observed in different tubera. Cytoarchitectural study revealed the absence of laminar and columnar cortical organization, whereas Golgi's method showed abnormal neuronal orientation and distribution. Pyramidal neurons manifested malrotation and orientation of the apical dendrites in aberrant directions. Large numbers of stellate cells in addition to medium-sized and small pyramids predominated in the intermediate and deep regions of the tubera. A generalized but focally accentuated disorder of cell migration and neuronal organization is postulated.

A Golgi study of cerebellar malformation in 13 trisomy.

The structure of cerebellar malformations in the brains of two infants with 13 trisomy has been studied by means of the Golgi method. Poorly organized cerebellar dysplasias (heterotaxias) are composed of Purkinje, Golgi and granule cells arranged and oriented in a disorderly fashion. The variable orientation and organization of the dendritic arbor of Purkinje cells within these cellular aggregates is supposed to be related to abnormal distribution of parallel fibers. Large ganglion cell heterotopias are not a homogeneous group, but two distinct types may be defined. First, Purkinje cell heterotopias which are located in the white matter of the cerebellum below the normally formed folia; these are composed of large neurons with arrested migration to the cortex. Secondly, multipolar cell heterotopias which are located in the deep white matter near the dentate and the roof nuclei, formed of neurons belonging to the deep cerebellar nuclei.

Adult type of leukodystrophy. Krabbe's disease?

A 24-year-old man developed progressive dementia in seven years. The patient suffered a severe bronchopneumonia and eventually died few days later. Brain coronal sections showed a soft gray-brownish discoloration of white matter of centrum ovale but the subcortical arcuate fibers and the interne capsule were preserved. Microscopically, the white matter showed marked loss of myelin and oligodendrocytes, abundant hypertrophic astrocytes and numerous "globoid cells". The latter showed strong positivity in immunostains for a mouse monoclonal antigalactocerebroside antibody. The presence of these cells in the brain white matter might be the morphological basis to classify the present case as one of Krabbe's Leukodystrophy.

Experimental diets for the study of lipid influence on the induced mammary carcinoma in rats: II--Suitability of the diets.

We have previously reported one method for obtention of experimental diets for the study of the effects of dietary lipids on the rat breast carcinoma. The purpose of this second part of the study was to develop a quality control system for demonstrating the suitability of these diets. This system is essentially based on the animals' growth control, their period clinical examination as well as the anatomopathological postmortem study of the animals submitted to such diets. Two groups of weaning rats, control (C) and hyperlipidic (HL), were submitted to a low-fat diet (N3) or a high-fat polyunsaturated--corn oil--diet (HL20) respectively. At 53 days of age all animals were induced with 5mg of dimethylbenz (a) anthracene. Experiments were ended when animals reached a mean age of 214 days. The results show: 1) a normal ponderal evolution of the animals in the two experimental groups with respect to two series of the same strain fed with a standard diet, and 2) the homogeneity of growth determined by the coefficient of variance study. On the other hand, neither the weekly clinical examination nor the anatomopathological post-mortem studies revealed any pathology that could be specifically attributed to nutritional imbalance. These results confirm the suitability of both diets for rat growth. Their use in the study of the effects of dietary lipids on the mammary carcinoma would satisfy the initial aim of guaranteeing the specificity of the results.

Congenital hemangiopericytoma: two cases of familiar presentation.

We report two cases of congenital hemangiopericytoma localized in the abdominal wall in the first patient and scalp in the second. The treatment of both cases consisted in the complete resection of the tumor mass. Four and two years later the patients remain asymptomatic. The special interest in this case report lies in the extremely low incidence of congenital hemangiopericytoma and that this is the first reference to affected siblings.