The degenerative diseases or syndromes in maturing central nervous system

The diagnosis of degenerative diseases or syndromes in the nervous system in based on their morphological picture. The changes occur in selected CNS structures or systems being induced in the course of more or less known processes sometimes with known, more often unknown etiology. Degenerative syndromes may be classified according to the topography of changes. They appear often with aging, but also in even greater number in infants. We tried to analyze the problem and find out to what degree the structure and topography of CNS degenerative changes in infants depend on maturity of nervous tissue constituting the background of pathologic process. The cases with two syndromes representative for small infants: progressive poliodystrophy of Alpers type and a degenerative syndrome with cerebral calcifications and disseminated demyelination were examined from this point of view. Our observations revealed that the stage of CNS development stipulates the type and topography of degenerative changes.

The white matter changes in microencephalic HIV infected infants. A preliminary report

The brains of six infants 14-34 months of age and with microencephaly (brain weight deficit 20-55.5%) were chosen from a group of cases vertically infected with HIV. The center of our investigations was focused on the white matter changes of which two types were observed in the examined brains. Within the periventricular white matter of four cases evident lesions consisting of myelin pallor and concomitant gliosis were recognized as HIV-1 infection related leukoencephalopathy. In all those cases myelination delay was also noted. In one case HIV encephalitis was diagnosed. Our observations suggest that in the majority of HIV infected infants changes resulting in the brain "too small for age" corelate with myelination delay coexisting with early-onset leukoencephalopathy. Because of the small number of cases in this study the results should be considered preliminary, and will require further investigations.

Eccrine syringofibroadenoma surrounding a squamous cell carcinoma: a case report

A 91-year-old man presented with a 9.0 x 7.0 cm exophytic mass on the dorsum of the right foot, surrounded by a scaling hyperkeratotic plaque-like lesion that had been present for many years. He had similar long-standing hyperkeratotic plaque-like lesions on both legs. Histopathologic examination of the exophytic mass revealed a well-differentiated squamous cell carcinoma surrounded by an eccrine syringofibroadenoma (ESFA). Histochemistry, immunohistochemistry and electron microscopy support this diagnosis. To our knowledge, this is the only reported case of ESFA being intimately associated with a malignant neoplasm.

Microencephaly in children congenitally infected with human immunodeficiency virus--a gross-anatomical morphometric study

A quantitative technique involving serial sectioning and semiautomatic morphometric analysis was used to assess the severity of the reduction in size of the major brain structures in cerebral hemispheres of children congenitally infected with HIV-1. Cerebral hemispheres from 12 children (18-48 months of age) who died of AIDS were sectioned into 5-mm-thick serial slabs and photographed. The cross-sectional areas of grossly recognizable brain structures were digitized, and the volumes were calculated according to Cavalieri's principle. The results were compared with those of an identically processed group of control brains from non-AIDS children. Analysis of the brain weight showed that there was a significant reduction in supratentorial and infratentorial weight in the AIDS group. The results of the morphometric study revealed that the loss in brain mass was associated with a statistically significant reduction in the total volume of both hemispheres, the entire cortex, white matter, and basal ganglia. Detailed analysis of individual brain structures also showed a significant reduction in volume of all cortical regions and most of the subcortical gray matter (e.g., caudate nucleus, putamen, globus pallidus, claustrum, and thalamus). It appears that in the microencephaly observed as a frequent sequel in pediatric AIDS, the loss of brain tissue is global and includes an almost proportional loss of cortex, subcortical gray matter and white matter.

Opportunistic infections of the central nervous system in children with HIV infection: report of 9 autopsy cases and review of literature

Central nervous system (CNS) abnormalities attributed to direct effects of HIV infection are seen in most of children with acquired immunodeficiency syndrome (AIDS). Secondary CNS infections with opportunistic and common pathogens are infrequent in this age group. We report 9 cases of opportunistic infection of the CNS found among 65 autopsy cases of pediatric AIDS. These included 4 cases of cytomegalovirus (CMV) infection, 1 of which was associated with aspergillosis, and 2 cases of candidiasis, 1 of which coexisted with Mycobacterium avium intracellulare (MAI) infection. There were also 2 cases of leptomeningitis, 1 due to Mycobacterium tuberculosis (MTB) and the other to Cryptococcus neoformans. In 1 child progressive multifocal leukoencephalopathy (PML) coexisted with mycotic encephalitis caused by an Aspergillus sp.

Pathological basis of spinal cord cavitation in syringomyelia: analysis of 105 autopsy cases

This report summarizes neuropathological, clinical, and general autopsy findings in 105 individuals with nonneoplastic syringomyelia. On the basis of detailed histological findings, three types of cavities were distinguished: 1) dilations of the central canal that communicated directly with the fourth ventricle (47 cases); 2) noncommunicating (isolated) dilations of the central canal that arose below a syrinx-free segment of spinal cord (23 cases); and 3) extracanalicular syrinxes that originated in the spinal cord parenchyma and did not communicate with the central canal (35 cases). The incidence of communicating syrinxes in this study reflects an autopsy bias of morbid conditions such as severe birth defects. Communicating central canal syrinxes were found in association with hydrocephalus. The cavities were lined wholly or partially by ependyma and their overall length was influenced by age-related stenosis of the central canal. Non-communicating central canal syrinxes arose at a variable distance below the fourth ventricle and were associated with disorders that presumably affect cerebrospinal fluid dynamics in the spinal subarachnoid space, such as the Chiari I malformation, basilar impression, and arachnoiditis. These cavities were usually defined rostrally and caudally by stenosis of the central canal and were much more likely than communicating syrinxes to dissect paracentrally into the parenchymal tissues. The paracentral dissections of the central canal syrinxes occurred preferentially into the posterolateral quadrant of the spinal cord. Extracanalicular (parenchymal) syrinxes were found typically in the watershed area of the spinal cord and were associated with conditions that injure spinal cord tissue (for example, trauma, infarction, and hemorrhage). A distinguishing feature of this type of cavitation was its frequent association with myelomalacia. Extracanalicular syrinxes and the paracentral dissections of central canal syrinxes were lined by glial or fibroglial tissue, ruptured frequently into the spinal subarachnoid space, and were characterized by the presence of central chromatolysis, neuronophagia, and Wallerian degeneration. Some lesions extended rostrally into the medulla or pons (syringobulbia). Although clinical information was incomplete, simple dilations of the central canal tended to produce nonspecific neurological findings such as spastic paraparesis, whereas deficits associated with extracanalicular syrinxes and the paracentral dissections of central canal syrinxes included segmental signs that were referable to affected nuclei and tracts. It is concluded that syringomyelia has several distinct cavitary patterns with different mechanisms of pathogenesis that probably determine the clinical features of the condition.

Stenosis of central canal of spinal cord in man: incidence and pathological findings in 232 autopsy cases

The central canal of the spinal cord is generally regarded as a vestigial structure that is obliterated after birth in 70% to 80% of the general population. This report describes the first detailed histological study of the human central canal in 232 subjects ranging in age from 6 weeks' gestation to 92 years. Whole spinal cords were harvested at autopsy and sectioned serially from the conus medullaris to the upper medulla. Histological findings and morphometric analysis of the cross-sectional luminal area were used to grade stenosis at seven levels of the canal. Varying grades of stenosis were present at one or more levels in none (0%) of 60 fetuses, one (3%) of 34 infants, three (18%) of 17 children, 21 (88%) of 24 adolescents and young adults, 67 (96%) of 70 middle-aged adults, and all 27 adults aged 65 years or older (100%). The stenotic process was most pronounced in the thoracic segments of the canal and involved more levels with higher grades of stenosis in older individuals. Histological findings consisted of disorganization of the ependymal epithelium, formation of ependymal rosettes or microcanals, proliferation of subependymal gliovascular buds, and intracanalicular gliosis. These features are consistent with a pathological lesion involving ependymal injury and scarring and are less compatible with an involutional or degenerative process. Stenosis of the central canal probably influences the anatomical features of syringomyelia and may account for variations in cavity formation such as the prevalence of holocord syrinxes in children, the formation of focal and paracentral syrinxes in adults, and the rare incidence of syrinx formation in many older individuals with acquired lesions known to produce syringomyelia.

Spinal cord pathology

The subject of spinal cord pathology can be addressed in several ways. This article tackles spinal cord pathology by examining the topic according to purely nosologic criteria. Topics discussed include malformations, traumatic injuries, vascular and circulatory diseases, tumors, infections and inflammatory diseases, demyelinating diseases, toxic-metabolic and nutritional diseases, degenerative diseases, and miscellaneous other disorders.

Prominent white matter cavitation in an infant with Alexander's disease

The clinical history and autopsy findings are reported on a case of infantile Alexander's disease (AD). The patient, a white baby girl, developed seizures at age 4 months accompanied by internal hydrocephalus. She died at age 11 months following a progressive, downhill course of profound psychomotor retardation, recurrent seizures and cachexia. The general autopsy was remarkable for cachexia. The formalin fixed brain and spinal cord were studied by light and electron microscopy (EM). The brain was normal in weight for age but showed diffuse pallor of white matter and marked cavitation involving the cerebral and cerebellar subcortical white matter, most profound in the frontal lobes. Microscopically the CNS showed classic features of AD with diffuse paucity of myelin and massive proliferation of astrocytes bearing Rosenthal fibers (RF). The latter appeared as granular osmiophilic deposits associated with 8-10 nm filaments within astrocytic processes and cell bodies by EM. This case of AD is remarkable for the extreme degree of cavitation. Cavitary changes affect up to one third of typical cases of AD and are invariably present in the frontal white matter. Affected patients are generally much younger and have a shorter clinical course than AD patients without brain cavitation. The dysmyelination of AD inversely parallels the temporal sequence of normal myelination and suggests a relative resistance of early myelinated structures to the presumed astrocytic defect causing AD. Adults with de novo formation of RF's in the CNS have a varied clinical and pathological appearance, rarely show brain cavitation and should probably be distinguished from classic AD in children.

Active muscle length reduction progressively damages soleus in hindlimb-suspended rabbits

This study describes the morphologic changes in rabbit soleus muscle following hindlimb suspension (HS) for 1 to 4 weeks (group A); or following HS with hindfeet passively dorsiflexed, by means of an elastic band, for 1 to 2 weeks (group B). In the latter, elastic band use allowed phasic contractions of foot extensor muscles against resistance and prevented 35% chronic soleus shortening, which occurred in group A animals. In group A, the soleus revealed progressive muscle atrophy and myofibrillar damage. Myofibrils underwent dissolution, muscle regeneration was ineffective, and adipose tissue developed from about 2-week suspension onward. Conversely, passive dorsiflexion of unloaded hindfeet was essential in maintaining mass and structural muscle integrity in the soleus of group B. It is hereby demonstrated that HS-induced soleus damage in the rabbit is progressive, and can be prevented, avoiding long-term shortening of soleus and its phasic unloaded contractions. Soleus sensitivity to unloading conditions, such as HS, tenotomy, and hypogravity, may depend on the particular physiology of this tonic antigravity muscle, engaged mainly in developing long-lasting isometric contractions in a stretched length.

Sinonasal primitive neuroectodermal tumor arising in a long-term survivor of heritable unilateral retinoblastoma

BACKGROUND

Patients who survive retinoblastoma (RB) are at risk for having second nonocular tumors, usually osteosarcomas, which often are fatal. Such patients almost always have bilateral RB.

METHODS

This article reports a woman who, at the age of 1 year had been cured of a unilateral RB by radiation therapy and enucleation. Eighteen years later, she had a sinonasal small cell tumor that rapidly recurred and proved fatal 2 months after surgical debulking. The tumor was studied by immunohistochemistry and electron microscopic (EM) examination.

RESULTS

It showed diffuse neuron-specific enolase staining, focal weak staining for chromogranin, synaptophysin, and Leu-7 monoclonal antibodies in paraffin-embedded, B5-fixed tissue (Great Lakes Diagnostics, Troy, MI). EM study showed an undifferentiated primitive neuroectodermal tumor with many polyribosomes, simple cell junctions, few microtubules, and rare dense core granules.

CONCLUSIONS

The combined immunohistochemical, ultrastructural, and clinical features of the tumor were interpreted as a sinonasal primitive neuroectodermal tumor with early neuronal differentiation. The tumor was pathologically indistinguishable from poorly differentiated olfactory neuroblastoma (ONB) and Ewing sarcoma.

Morphological, immunocytochemical and growth characteristics of three human glioblastomas established in vitro

The human glioblastoma-derived cell lines 86HG-39, 87HG-28 and 87HG-31, used for the production of monoclonal antibodies (mAbs) against glioma-associated antigens (GAA), were characterized in terms of morphology, growth behaviour, chromosomes and antigen expression. In the primary tumours, differential expression of glial fibrillary acidic protein, S100 protein, Leu-7 and GAA as defined by mAbs MUC 2-39, MUC 2-63 and MUC 8-22 was demonstrated. Receptors for epidermal growth factor (EGFr) and nerve growth factor (NGFr) were found in many cells in short-term cultures, but the transferrin receptor (Tr) was found in only a few cells of 87HG-28. In permanent cell lines, differentiation antigens and EGFr decreased and Tr increased markedly. NGFr and GAA remained stable. Transplantation tumours of 86HG-39 were partly positive for Tr and GAA. Chromosomal analysis revealed that the 86HG-39 and 87HG-28 cell lines had a hypodiploid or diploid stem line with lines in the hypotetraploid to tetraploid region for 50 in vitro passages. The 87HG-31 cell line had chromosomal patterns in the hypotriploid to triploid region. A gain of chromosomes was seen in the groups C7, C8, C10, D14, F19, F20, G21, G22. The variability of antigens in these tumours and especially during long-term cultivation probably reveals an ability to influence the growth of malignant glioma cells via the respective effector molecules.

Myofibrillar disruption in the rabbit soleus muscle after one-week hindlimb suspension

Relevant muscle- and species-specific differences may be found in the reaction of muscles to hindlimb suspension. This problem has been studied in 5 rabbits following a one-week hindlimb suspension, and in 5 ground-based controls. The soleus and the tibialis were prepared for light and transmission electron microscopy. In suspension the animals occasionally extended and flexed the hindlimbs, but, when standing still, their hindfeet were plantar-flexed to an angle of 180 degrees. In this position the length of the soleus was determined to be 35% less than in controls, whereas that of the tibialis was 30% more. Histologically, the tibialis fibers usually exhibited a preserved sarcomeric pattern, whereas soleus fibers displayed a regular sequence of areas of shortened sarcomeres, alternating with areas of myofibrillar disruption. These findings demonstrated that hindlimb suspension induces a focal breakdown of the soleus myofibrils, probably dependent on the reduced longitudinal tension of the suspended soleus and its phasic contractions against no load. It is conceivable that similar factors could also be responsible for soleus muscle atrophy induced by hypogravity as well as by other clinical conditions during which a stressful plantar flexion of the feet occurs against no load.

Radioimmunodetection of human glioma xenografts by radiolabelled monoclonal antibodies

Radiolabelled monoclonal antibodies (131I-MUC 8-22, 131I-MUC 2-63) were used for external scintigraphy of human glioma xenografts. To induce transplantation tumors. 5 x 10(6) cells (85HG-66) of an in vitro established human malignant astrocytoma (N66/85) were inoculated s.c. in BALB/c-nu/nu mice. The labelling of the immunoglobulins with 131iodine was carried out according to the iodogen method, the nude mice, bearing xenograft, received 30 m. 131I-labelled intact monoclonal immunoglobulins (200mCi: 7,4MBq) and the imaging was performed on days 4, 8 and 12 after the application. After 4 days, a clear tumor accumulation of iodinated MUC 2-63 antibodies recognizing surface determinants was visible. This enrichment of monoclonal antibodies (MAbs) led to a characteristic tumor presentation on day 8. Obviously, the MUC 2-63 antibodies remain in the tumor tissue for a long time, so that even on day 12 satisfactory tumor imaging is possible. On the other hand, neither with normal mouse IgG nor with MUC 8-22 antibodies - which react with intracellular structures - could a tumor localization be achieved. The result of the studies on the distribution of 131I-MUC 2-63 on day 19 was that the activity in the tumor tissue was about 4.4 times higher than in the blood and even more times higher than in solid organs.

Amebic meningoencephalitis in a patient with AIDS caused by a newly recognized opportunistic pathogen. Leptomyxid ameba

A fatal case of meningoencephalitis due to a leptomyxid ameba in a patient with the acquired immunodeficiency syndrome is presented. This opportunistic organism has not been previously recognized as a human pathogen. A 36-year-old male intravenous drug abuser died after an 18-day hospital course heralded by fever and headache and followed by nuchal rigidity and hemiparesis. Computed tomography of the head showed multiple hypodense lesions. Neuropathologic examination showed that in addition to human immunodeficiency virus encephalomyelitis, there was multifocal meningoencephalitis with trophozoites and cysts morphologically indistinguishable from those of Acanthamoeba. These organisms were also found in the kidneys and adrenal glands. By immunofluorescence, the parasites showed antigenic identity with a free-living leptomyxid ameba and failed to react with any of a spectrum of antiacanthamoeba antisera. This emphasizes the importance of immunofluorescence identification of morphologically indistinguishable ameba species.

Medullomyoblastoma in an adult

Medullomyoblastoma is a rare histologic variant of medulloblastoma. Of the 20 cases reported in the literature, 19 were in children ages 2.5 to 10.5 years and one was in a 26-year-old woman. In the reported adult case the myogenic component of the tumor was leiomyosarcomatous. The authors report a case of medullomyoblastoma with a rhabdomyosarcomatous component in a 40-year-old man with light microscopic, immunohistochemical, and ultrastructural findings. The histogenetic theories regarding this tumor include that it is a teratoma, or that the myogenic component arises from the perivascular or leptomeningeal ectomesenchyme, or pluripotential neuroectodermal cells, or endothelial cells. The authors' findings do not elucidate the histogenesis but argue against an endothelial origin of the rhabdomyoblastic component.

Muscle fibre loss and reinnervation after long-term denervation

Cutaneous pectoris muscles of frog (Rana temporaria) were investigated 19.5-40 months after denervation. On whole mounts a heavy reduction in size and number of muscle fibres is noticed; in two muscles studied with semithin and ultrathin sections the number of remaining muscle fibres is 149 and around 120, while one of the contralateral muscles contains 250 and control muscles of equal sized frogs between 220 and 320 (n = 18) fibres. By electron microscopy muscle fibres undergoing degeneration or phagocytosis can be seen (3 of 20 muscle fibres present in a single ultrathin cross-section). On the other hand several profiles contained within one common basal lamina sheath are present in 14 of 20 fibres, indicating satellite cell proliferation. In one preparation 40 months after denervation not a single muscle fibre or axon is present, suggesting that eventually, without nerve supply, muscle fibres entirely disappear. Upon spontaneous reinnervation or implantation of the hypoglossal nerve 16 months after denervation, synapses are formed with the remaining muscle fibres. When studied 3.5-24 months after nerve implantation muscles innervated by few axons only (less than 10, 10-20 axons) contain a low number of muscle fibres (mean 44 +/- 41 SD, n = 6), while all muscles with a larger number of axons have more than 150 muscle fibres (n = 6). This indicates that unless large numbers of axons regenerate and/or when reinnervation is delayed muscle fibre loss continues to occur. The presence in one muscle of motor axons but only six muscle fibres 24 months after nerve implantation indicates that muscle fibre loss cannot be reversed, or recovery is extremely slow. This observation is interpreted as evidence for the exhaustibility of the satellite cell pool.

Computed tomography in global cerebral cortical ischemia of the neonate and young infant

The authors have encountered three unique neonates with global cerebral cortical ischemia. The pathogenesis and computed tomography scans of these patients who sustained profound hypoxemia is described. Follow-up computed tomography scans in each case demonstrated generalized loss of cortical substance.

Myopathy with tubular aggregates in a patient adrenalectomized for Cushing's syndrome

We report a patient with attacks of muscle weakness and mild myopathy with tubular aggregates, following bilateral adrenalectomy for adrenal Cushing's syndrome and replacement therapy with cortisone acetate and 9 alpha-fluorohydrocortisone. The replacement of 9 alpha-fluorohydrocortisone therapy by desoxycorticosterone acetate therapy led to the cessation of the attacks.

Light and electron microscopic identification of nerve terminal sprouting and retraction in normal adult frog muscle

A combined light and electron microscopic study was performed on neuromuscular junctions of normal adult frogs. In a previous investigation signs of new synapse formation, as well as abandoned former synaptic sites, have been observed in normal muscles (Wernig, Pécot-Dechavassine & Stöver, 1980a, b). Here we performed a detailed light and electron microscopic correlation to investigate those parts of junctions which, after staining for cholinesterase (ChE) and presynaptic axon terminals, were suspected either to be newly formed or sites abandoned by the presynaptic nerve and the Schwann cell. Thin presynaptic nerve branches, enclosed by Schwann cell sheaths along most of their length, formed synaptic contacts with the muscle fibre only at small circumscribed areas. In these regions post-synaptic secondary folds (invariably present at mature synapses) were either missing or were less well developed. At these small contacts, binding sites for fluorescein-labelled alpha-bungarotoxin were usually present. At other sites the ChE reaction product was present but an axon could not be detected in silver-stained preparations. Electron microscopic observation revealed post-synaptic secondary folds filled with ChE reaction product while the presynaptic axon and Schwann cell were missing. The sites with ChE remnants can thus be regarded as abandoned former synaptic contacts. No binding of fluorescein-labelled alpha-bungarotoxin could be detected at such sites. These findings confirm earlier suggestions that synaptic contacts in frog muscle are normally undergoing continual remodelling. The lack of binding sites for fluorescein-labelled alpha-bungarotoxin at abandoned synaptic sites suggests that a neural or Schwann cell factor is important for the maintainance of synaptic acetylcholine receptors.

Brain involvement in generalized argyria

Cutaneous argyria was diagnosed in a 59-year-old woman. Manic depressive psychosis developed at about the same or a short time thereafter. The patient died 6 years later from a ruptured aortic aneurysm. At autopsy silver deposits were seen in skin, mucous membranes, heart, kidney, and liver. In the central nervous system the leptomeninges and choroid plexuses contained silver granules. In addition, silver granules were visualized in the walls of many intraparenchymal vessels, particularly of the basal ganglia, hypothalamus, substantia nigra, and cerebellum. Progressive glial changes and cellular gliosis were evident in many areas of the brain. With the electron microscope the deposition of silver granules in basal membrane structures of the choroid plexus and intracerebral vasculature was amply confirmed. Furthermore, silver deposition was seen in brain parenchymal cells inside bodies of apparently lysosomal nature. The silver content of various brain regions was determined by absorption spectrophotometry.

Persistence of nerve sprouting with features of synapse remodelling in soleus muscles of adult mice

An increase in the number of nerve branches of the unmyelinated axon terminals with increasing age was observed in normal adult mouse motor endplates. In addition, ultrastructural investigation revealed signs of nerve retraction. A combined light and electron microscopic investigation was performed on zinc-iodine-osmium stained endplates in soleus muscles. The number of branch points in a synapse, endplate length and muscle fiber diameter were evaluated in "young adult" (3 months) and adult (6 and 11 months) mice. For all 3 parameters, 3-month-old animals had the lowest values. Eleven-month-old animals had more branch points and larger endplate lengths than 6-month-old animals while there was no significant difference in fiber diameters. Branch point numbers and endplate length were correlated in each muscle while fiber diameters did not correlate with any of the other parameters. The ultrastructure of 15 thin nerve branches--likely candidates for new branches--was investigated in serial section and in 14 of them synaptic contacts were found. Near such contacts, empty gutters, possibly abandoned former synaptic sites, were present in several cases. It is concluded that there is continual nerve sprouting in synapses of adult mice and that sprouts form synaptic contacts. The possible signs of nerve retraction observed indicate that, as in the frog, synaptic contacts in mouse muscles undergo some continual remodeling.

Presence and absence of virus particles in hybridomas secreting monoclonal antibodies against gliomas

Hybridoma clones were produced by fusion of splenocytes from glioma-immunized hosts and the X63-Ag8.653 mouse myeloma line and Y3-Ag.1.2.3. rat myeloma line. Oncornavirus particles were found in all clones descending from the mouse myeloma line. No virus particles could be found in either the spleens of immunized Balb/c mice and Fischer rats or in the rat myeloma line and the hybridomas derived from it.

Crystalline aggregates of protein-glycogen complexes (alias 'virus-like particles') in skeletal muscle: report of a case and review of the literature

Crystalline arrays of so-called 'virus-like particles' were found in post-mortem samples of skeletal muscle obtained from an 11-month-old female infant. In a large number of skeletal muscle fibres crystalline inclusions were abundant, variously configurated and positively stained with a cytochemical method for polysaccharides. A battery of enzymatic tests, including some with diastase and alpha-amylase, was, however, entirely noncontributory. A muscle biopsy studied 5 months before death had disclosed no crystalline inclusions of any kind. The literature concerning similar cases of 'virus-like particles', crystalline glycogen aggregates or protein-glycogen complexes in muscle is reviewed. Possible reasons underlying the aggregation of protein-glycogen complexes into crystalline arrays are discussed.

Immunological aspects of experimental brain tumors (review)

Evidence that experimental neural tumors contain glia specific and glioma-associated antigens is reviewed. The fact that glioma cells share antigens with normal glia cells is of crucial importance for the histogenetic immunodiagnosis of intracranial neoplasms. Moreover, the increasing use of in vitro techniques in neuro-oncology has accentuated the necessity for employment of cell-type characteristic antigens. This allows for objective identification of the various types of brain tumor cells, and also for ascertaining the neurological nature of long-term cultured cells. Humoral and cell-mediated immune reactions to gliomas could be demonstrated in autochthonous and syngeneic hosts. Since glioma-associated antigens are rather weak and glioma cells are low immunogens, various approaches for enhancing glioma-cell immunogenicity have been described, such as treatment with membrane-modifying enzymes, or haptenization with various chemicals. Recently, nitrophenylation of glioma cells has become available for artificially increasing the immunogenicity of these cells. Furthermore, methods have recently been worked out by which monoclonal antibodies of predefined specificity can be produced in order to analyze the nature of glioma-associated antigens. Such methods may have a significant impact on clinical immunodiagnostics, and perhaps on the development of new immunotherapeutic approaches.

A case of adrenoleukodystrophy in a girl. Genetic considerations

We report the case of a girl who developed leukoencephalopathy and adrenal atrophy and died at 3 years of age. Histologically, demyelination, gliosis, perivascular lymphocytic cuffing and sudanophilia were present in the brain. The adrenal cortex was atrophic. Ultrastructurally, there were numerous cytoplasmic inclusions in brain macrophages, consisting of two leaflets separated by an intervening space of variable low electron density. Brain tissue cholesterol esters contained a high proportion of long chain fatty acids. The findings are discussed and compared with those in the literature. Emphasis is placed on the fact that the disease occurred in a girl in apparent contradiction to the commonly accepted X-linked hereditary transmission of adrenoleukodystrophy. Some possible genetic explanations for our case are put forward.

A new rat mutant with defective overhairs and spongy degeneration of the central nervous system: clinical and pathologic studies

A new spontaneous autosomal recessive mutation with a nervous disorder and a hair anomaly occurred in a colony of Sprague Dawley rats. The animals developed a generalized body tremor at about 15 days of age, and with increasing age a progressive flaccid paresis occurred. Light microscopy revealed spongy changes in the central nervous system. The mutant was designated zitter rat (zi).

Intra-astrocytic glycogen granules and corpora amylacea stain positively for polyglucosans: a cytochemical contribution on the fine structural polymorphism of particulate polysaccharides

A cytochemical procedure for polysaccharides was carried out on a brain biopsy specimen, the thin-section study of which had shown excess glycogen granules and the corpora amylacea variety of polyglucosan bodies. Both granules and amyloid bodies were stained positively in contrast to the remaining structures of the brain tissue which remained unstained. This demonstrates that beta-granules as well as filamentous and amorphous components of amyloid bodies are just different aspects of the polysaccharide molecule. Up to now the same kind of cytochemical evidence has been supplied for Lafora bodies of human material and Lafora-like bodies of rat material. The present study on corpora amylacea of human material shows that amyloid, Lafora, and Lafora-like bodies all behave the same way when stained for polysaccharides.

Myeloma neuropathy: passive transfer from man to mouse

Mice were injected daily, for up to 10 weeks, with purified monoclonal immunoglobulin G from patients with myelomatous polyneuropathy or benign gammopathy. The animals developed a demyelinating polyneuropathy with slowed nerve conduction velocities. The putative antinerve factor may be an antibody since injection of Fab fragments from the monoclonal immunoglobulin G produced a similar demyelination. This provides evidence of a circulating factor in the serum of myeloma patients with polyneuropathy that reproduces typical features of the human disease on passive transfer. This disorder is thus distinguished from other neuropathies that occur as remote effects of malignant disease but have no identified pathogenic factors associated with them.

Muscle cells in a nerve trunk of a frog muscle

Three muscle fibers were identified by electron microscopy within a nerve of a frog muscle. They resembled extrafusal muscle fibers but were located in an endoneurial rather than in an endomysial compartment. To call these endoneurial muscle fibers the obvious continuation of extrafusal fibers of a muscle spindle is certainly unwarranted; to label these fibers ectopic and to let the matter rest there is probably an understatement of sorts.

Abandoned synaptic sites in muscles of normal adult frog

In previous investigations light microscopic cholinesterase (ChE) deposits without any nerve were found adjacent to normally occupied parts of a frog neuromuscular synapse [4, 9]. After identifying one such site at the light microscopic level ultrathin sections were cut and viewed with an electron microscope. ChE reaction product-filled secondary, clefts were observed in the region studied but a nerve was invariably missing. From this it is concluded that these loci are former synaptic sites from which nerve and Schwann cell have retracted, When incubating muscles with fluorescence-labelled alpha-bungarotoxin, all 23 abandoned sites found in 6 muscles remained bare of visible amounts of label. This indicate that receptor molecules eventually disappear from the synaptic membrane after retraction of the nerve and Schwann cell. No information as to the underlying time schedule of nerve retraction, turnover of ChE and alpha-bungarotoxin binding sites was obtained. Taken together with the evidence for synapse new formation in untreated frog muscles obtained previously [9, 11] the present observations indicate some ongoing remodeling of frog neuromuscular junction.

Light and electron microscopic identification of a nerve sprout in muscle of normal adult frog

Recent evidence from this laboratory indicates that axonal sprouting (and regression) occurs in neuromuscular junctions of normal adult frogs. In the present investigation, the appearance of a single nerve branch, which from light microscopy was assumed to be a sprout, was studied in ultrathin serial sections. In confirming the light microscopic evidence small synaptic contacts were found, which showed characteristics of new synapse formation. Unexpectedly, the Schwann cell surrounding the axon extended several microns distally from the axon tip. It appears that nerve sprouting (and regression) is a physiological event in adult frog muscles.

Ultrastructure of a cerebral white matter lesion in a 41-year-old man with Leigh's encephalomyelopathy (LEM)

A brain biopsy taken from a 41-year-old man with Leigh's encephalomyelopathy (LEM) was studied under the electron microscope. The sample of cerebral white matter revealed degenerated oligodendrocytes, reactive astrocytes and scavenger cells filled with miscellaneous debris. Myelin underwent splitting and vacuole formation as well as lamellar and vesicular dissolution. Degenerative and reactive changes were prominent in the axons, many of which were calcified. There was marked fibrous gliosis of the tissue and the extracellular space was enlarged. The small vessels were notably involved; evidence of capillary growth was also found. In sum, the overall picture was one of loss of tissue continuity, loss of axons and loss of myelin, opposite to which stood expansion of the extracellular space, accumulation of filament-filled astroglial process, hypertrophy and hyperplasia of the capillaries and increase of the tissue cellularity. The study has confirmed and defined at the ultrastructural level the well-known histological features of LEM. However, the formal, let alone the causal pathogenesis of the disease remains as obscure as ever.

The humoral antibody response of rats immunized with chemically modified syngeneic brain cells and glioma cells

Six-month-old Fischer rats (F344) were given the carcinogen methylnitrosourea in their drinking water. Of the induced brain tumors, four were established in culture and propagated as 78FR-G-219 (pleomorphic glioma), 78FR-G-299 (astrocytoma), 78FR-G-284 and 78FR-G-344 (mixed glioma) permanent lines. All cell lines produced S-100 protein and grew as tumors when inoculated s.c. or i.c. in syngeneic hosts. A comparative study of the antigenicity of these lines at different passage levels was carried out using native and chemically modified cells. Syngeneic rats were immunized with cells conjugated with dimethylsulfate and trinitrobenzene sulfonic acid. The immune response was characterized and quantified by an indirect immunofluorescence method and by a complement-dependent microcytotoxicity test. Chemical modification of the tumor cells enhanced antigenicity of the treated cells. The best results were attained with trinitrobenzene sulfonic-acid-treated cells and constituted a two-fold increase in the cytotoxicity index. Cytotoxicity values varied in the different cell lines. Antisera raised with trinitrobenzene sulfonic-acid-modified cells of all lines cross-reacted with cells of all lines. Cytotoxicity values were insignificantly reduced by absorbing the antisera with a variety of syngeneic tissues. Antisera raised against native syngeneic brain cells showed virtually no cytotoxicity for glioma cells. Antisera raised against syngeneic brain cells treated with trinitrobenzene sulfonic acid, however, were slightly cytotoxic for normal brain cells and glioma cells as well. The results of the present studies show that antigenicity of glioma cells can be definitely raised with trinitrobenzene sulfonic acid treatment. Furthermore, it would seem that haptenization of glioma-associated antigens may be a promising approach ot the study of glioma-host interactions.

Definition of a cell clone with astroglial characteristics derived from a chemically induced rabbit brain glioma

Three-month-old rabbits were started on a fortnightly schedule of intravenous injections of N-methyl-N-nitrosourea. All but two of the central nervous system tumors induced in this manner were propagated in culture as permanent cell lines. On the 76RB-G-414-H line established from a grade 2 astrocytoma of this series of neoplasms, a cloning procedure was carried out using a laser microbeam. The clonal line originated in this way has been maintained in long-term culture and given the 76/RB-G-414-H-C designation. The cells of the clone display invariably a bipolar or multipolar configuration with long processes. Intermediate filaments are common and even abundant in some cells. Positivity for S-100 and GFA proteins is a regular finding in these cells. In addition, dibutyryl cyclic adenosine monophosphate treatment reduces cell division and stimulates cell process formation of these cells. Thus, it appears that we succeeded in establishing in vitro and maintaining in long-term culture a clone of tumor cells with astrocytic characteristics.

Morphological, immunocytochemical and biological characteristics of experimental rabbit brain tumors in tissue culture

Brain tumors were induced in 3-month-old rabbits of either sex by repeated intravenous injections of N-methyl-N-nitrosourea. Twelve brain tumors (6 pleomorphic gliomas, 5 grade 2--3 astrocytomas, 1 grade 2--3 oligodendroglioma) were established in culture and, with the exception of 2 neoplasms, were propagated in vitro as permanent cell lines. The glial nature of all cell lines was ascertained at several passage levels by testing the cells for the production of S-100 and GFA. It could be shown that most cells of all lines fluoresced positively for the S-100 protein, albeit differences in intensity of fluorescence were clearly noted between cells of the same culture and between different cultures. In general, astrocytoma cell lines had the strongest fluorescence. Pleomorphic glioma cells but especially astrocytoma cells reacted positively also for the GFA protein. Surprisingly enough, isolated cells of the oligodendroglioma line also showed evidence of GFA production. Exposure of cultures of rabbit glioma cells to db-cAMP for 8--10 hr resulted in inhibition of cell proliferation and stimulation of process formation. Furthermore, positive fluorescence for the S-100 and GFA proteins was more intense in cells treated with db-cAMP than in untreated cells. The latter observation may indicate that production and/or accumulation of glial proteins also was enhanced during the stationary phase of cell cultures.

Selected morphological immunocytochemical and growth characteristics of three experimental rat gliomas and of their cells in vitro

Tumors of the nervous system were induced in Sprague-Dawley and Long-Evans rats by weekly administrations of 6 mg/kg N-methyl-N-nitrosourea in the drinking water. Three of these tumors, a grade 2 mixed glioma, a grade 2 to 3 astrocytoma and a grade 1 to 2 oligodendroglioma, were established in culture and propagated in vitro. The mixed glioma strain (75SD-G-376) and the astrocytoma line (75SD-G-420) were repeatedly subcultured, cloned at passage 90 and 120 and designated as 75SD-G-376C and 75SD-G-420C clone, respectively. The growth rate of the oligodendroglioma cell strain (77LE-G-180) was very low and the cells died off after the 5th in vitro passage. The glial nature of all lines was ascertained by demonstrating the presence of the S-100 protein in the culture cells. 2 1/2 years after the establishment in vitro of the 75SD-G-376 and 75SD-G-420 primary cultures, mass cultures as well as clones derived from them are still producing S-100 and thus are clearly comparable to the primary cultures, at least in this respect. From a morphological standpoint based on light microscopy, cells of clonal lines with relatively few and short processes differ, however, from cells of primary cultures and their uncloned lines. Therefore, the cell morphology of these clones can be viewed upon as a form of adaptation to the in vitro conditions. It can be concluded that permanent cell lines with well-defined properties can be grown from experimental brain gliomas successfully established in culture and maintained in vitro.

Tumor specific fluorescent and complement-dependent cytotoxic antibodies in the serum of rats with chemically induced brain gliomas

Brain tumors were induced in Sprague-Dawley and Long-Evans rats by administration of N-methyl-N-nitrosourea in the drinking water. Of these tumors, a grade 2 mixed glioma, a grade 2 to 3 astrocytoma and a grade 1 to 2 oligodendroglioma were established in vitro, maintained in culture and designated 75SD-G-376, 75SD-G-420 and 77LE-G-180, respectively. Of these mass cultures, two were successfully cloned and are currently available as 75SD-G-376C and 75SD-G-420C cell lines. Clonal lines produce S-100 protein and grow as tumors when isografted in young rats. Using the cultured cells as target cells , specific antibodies were searched for in the sera of the rats with the primary tumors by means of an indirect fluorescent antibody staining method and a complement-dependent antibody-mediated microcytotoxicity assay. Fluorescent and cytotoxic antibodies were demonstrated in the sera of the mixed glioma- and astrocytoma-bearing animals. However, a variable proportion of cells of the 75SD-G-376 and 75SD-G-420 lines showed no reaction with the corresponding sera. Furthermore, cytotoxic antibodies had a lytic effect on the autologous glioma cells only in the presence of rabbit complement.

Ultrastructural cytochemical demonstration of peroxidase-positive monocyte granules: an additional method for studying the origin of mononuclear cells in encephalitic lesions

Unlike lymphocytes, blood monocytes possess in their cytoplasm peroxidase-positive (azurophil) granules (ppg) which largely correspond to the homonymous organelles of neutrophil granulocytes. We tested whether ppg, demonstrated cytochemically at the submicroscopic level, could serve as markers of monocyte-derived reactive mononuclear cells in encephalitic lesions. Samples of cerebrocortical tissue from adult albino mice with experimental yellow fever virus encephalitis were incubated in a medium containing diaminobenzidine and H2O2 for localization of peroxidatic activity. Mononuclear cells exhibiting ppg were found (1) in the lumen of brain venules, (2) in different stages of migration through the walls of such vessels, (3) in perivascular areas, (4) in the glioneuropil, either loosely scattered or forming small clusters, (5) in a satellite position to neurons, and (6) in leptomeningitic inflitrates. Several mononuclear elements harboring ppg had assumed an elongated, rod cell-like outline. Amongst the peroxidase-negative mononuclears were fully developed brain macrophages and elements showing morphologic features characteristic of activated lymphocytes. Most mononuclear cells without ppg resembled the peroxidase-reactive ones. The results of this study provide direct evidence in favor of a monocytic origin of, at least, numerous reactive mononuclear elements in encephalitic lesions. The approach followed in the present study is not suitable for quantitative investigations of the histogenesis of mononuclear cells responding to brain injuries, since emigrated blood monocytes rapidly lose their ppg, particularly, when they display enhanced phagocytic activity.

Myasthenia gravis: further electrophysiological and ultrastructural analysis of transmission failure in the mouse passive transfer model

Using the mouse passive transfer model the mean amplitude of miniature endplate potentials and endplate potentials of mice treated with myasthenic immunoglobulins was markedly decreased. Miniature endplate potential frequency and quantum content of endplate potentials were normal, arguing against a major presynaptic disarrangement. Under electron-microscopy no gross structural alterations of endplates were demonstrated. It is concluded that the mouse passive transfer model closely resembles human myasthenia gravis of recent onset.

Immunofluorescence study of lymphocytic infiltration in gliomas. Identification of T-lymphocytes

Five human brain tumours (3 glioblastomas and 2 astrocytomas) and 5 rat brain tumours induced in Sprague--Dawley animals by systemic administration of N-methyl-N-nitrosourea (3 pleomorphic gliomas and 2 mixed gliomas) were studied. The human brain tumours were surgical specimens excised from patients with no cranial surgery prior to their disease. The experimental brain tumour had been adapted to tissue culture, propagated in vitro and then transplanted to immunocompetent and immunodeficient rats of the same stock. The above-described material was selected in consideration of the mononuclear cell infiltrates occurring in these tumours. Frozen sections of human and rat gliomas, the latter both primary and transplanted, were prepared and investigated as to the presence of T-lymphocytes within the mononuclear round cell infiltrates. This was done with the indirect immunofluorescence method using rabbit antisera against man and rat T-lymphocytes. With this technique a variable percentage of T-lymphocytes was demonstrated in the cell infiltrates of human and rat gliomas alike. The tumour transplanted in thymectomized rats showed only isolated, scattered, positive-reacting cells, i.e., cells recognizable as T-lymphocytes by the above method. The results can be interpreted as circumstantial evidence for the occurrence of tumour-specific and/or tumour-associated antigens in the parenchymal cells of spontaneous and chemically-induced gliomas.