RESUMEN
Alzheimer's disease is characterized by relative sparing of primary sensory and motor cortex and a lack of sensory or motor symptomatology. We report a case of presenile onset dementia accompanied by a slowly progressive hemiparesis. Autopsy examination showed severe pathologic involvement of somatosensory cortex with neuritic plaques and neurofibrillary tangles, in addition to degeneration of the nucleus basalis and locus ceruleus. Neurochemical and immunocytochemical studies showed a moderate cortical cholinergic deficiency with normal somatostatin-like immunoreactivity and a profuse immunostaining of somatosensory cortex with the Alz-50 antibody. These unusual features emphasize that Alzheimer's disease is extremely variable in its clinical symptomatology, pathologic distribution, and neurochemical dimensions.
Asunto(s)
Enfermedad de Alzheimer/fisiopatología , Demencia/fisiopatología , Hemiplejía/fisiopatología , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/patología , Encéfalo/metabolismo , Encéfalo/patología , Química Encefálica , Demencia/metabolismo , Demencia/patología , Femenino , Humanos , Inmunohistoquímica , Persona de Mediana EdadRESUMEN
Cortical Lewy bodies may be difficult to differentiate from Pick bodies by the usual staining methods. This problem is illustrated in a case of progressive dementia with parkinsonian features. Lewy bodies were found, not only in the pigmented nuclei in the brainstem and in the cerebral cortex, but also in the dentate fascia, a predilection site for Pick bodies. The inclusion bodies were compared with the inclusion bodies in a case of Pick's disease. Intense argyrophilia of the cortical inclusion bodies argued in favor of Pick bodies; antibodies to phosphorylated neurofilaments reacted with the cortical inclusions and with classical Pick bodies, but antibodies to paired helical filaments reacted only with the Pick bodies. The most convincing evidence, that the inclusions were Lewy bodies, was obtained by electron microscopy. The filaments in the inclusions showed fuzzy deposits of electron dense material, characteristic for filaments of Lewy bodies. This contrasted with the smooth filaments of the Pick bodies. It is concluded that cortical inclusions in brains from patients with Lewy bodies in the pigmented nuclei of the brainstem most likely represent Lewy bodies. This can be confirmed by examining the ultrastructure of the inclusions.
Asunto(s)
Corteza Cerebral/patología , Demencia/patología , Cuerpos de Inclusión/ultraestructura , Neuronas/citología , Enfermedad de Parkinson/patología , Anciano , Anticuerpos Monoclonales , Corteza Cerebral/ultraestructura , Demencia/complicaciones , Hipocampo/patología , Hipocampo/ultraestructura , Humanos , Técnicas para Inmunoenzimas , Proteínas de Filamentos Intermediarios/análisis , Filamentos Intermedios/ultraestructura , Masculino , Microscopía Electrónica , Proteínas de Neurofilamentos , Neuronas/ultraestructura , Enfermedad de Parkinson/complicaciones , Sustancia Negra/patología , Sustancia Negra/ultraestructuraRESUMEN
A quantitative survey of calcitonin gene-related peptide (CGRP) in brain, peripheral nerve and cerebrospinal fluid (CSF) was performed using radioimmunoassay (RIA) with antiserum against synthetic hCGRP. High levels (approximately 2000-15,000 fmol/mg protein) were found in the dorsal spinal cord, dorsal nerve and trigeminal nerve. Relatively large amounts (500-2000) were found in parts of the hypothalamic-pituitary axis, peripheral nerve and, for the first time, in the locus caeruleus. Low levels of CGRP (less than 500) were detected in the cerebrum, subcortical nuclei and cerebellum. CGRP, not previously reported in CSF, was detectable in all of 27 CSF specimens with mean values of 30 +/- 4.5 pmol/L (SE). Simultaneous plasma CGRP levels were higher and, when elevated by antihypertensive treatment were not increased in CSF, just as astronomical plasma levels of calcitonin in medullary carcinoma of the thyroid are not reflected in CSF. Our data confirm and extend the results of previous human and animal studies with evidence of species variation: humans have low CGRP levels in subcortical nuclei whereas high levels have been found in rat caudate-putamen and amygdala. The high level of CGRP in the locus caeruleus, the major source of noradrenergic neurotransmission in the CNS, is in harmony with the presumed functions of the LC and the very potent hemodynamic activity of CGRP.
Asunto(s)
Encéfalo/metabolismo , Neuropéptidos/metabolismo , Péptido Relacionado con Gen de Calcitonina , Humanos , Locus Coeruleus/metabolismo , Neuropéptidos/líquido cefalorraquídeo , Nervios Periféricos/metabolismo , Médula Espinal/metabolismo , Distribución TisularRESUMEN
Delayed radiation damage of normal brain can be a devastating complication of radiation therapy and generally occurs months to years after the initiation of therapy. Primarily restricted to the white matter, radiation damage is characterized by a number of histopathologic changes including coagulation necrosis, vascular alterations with fibrinoid necrosis, edema, and demyelination. Normal dogs were exposed to either 10, 15, or 30 Gy of X rays to a single hemisphere and the gross and histopathologic changes were evaluated qualitatively. A spectrum of changes was observed ranging from white matter edema to extensive white matter necrosis, and the extent, location, and type of damage were dependent upon radiation dose. Histopathologic changes were separated into three major categories based on the character and size of the lesions, with the most severe changes being similar to the types of changes described in human patients who have developed delayed radiation necrosis. Less severe forms of damage such as multifocal, sometimes confluent areas of microscopic necrosis with spongiotic borders and edema with severe axonal swelling were also observed. These latter changes are not well recognized as being due to radiation. The findings of this study also indicate that many of the changes ascribed to combined treatment with methotrexate and radiation in humans are induced in the normal dog brain by radiation alone. The results of his study show that the dog is a suitable model of the human brain for studying radiation brain injury and may be useful for investigation of drug-radiation interactions.
Asunto(s)
Encefalopatías/patología , Traumatismos Experimentales por Radiación/patología , Animales , Encéfalo/patología , Encéfalo/efectos de la radiación , Edema Encefálico/etiología , Edema Encefálico/patología , Perros , Relación Dosis-Respuesta en la Radiación , Necrosis , Factores de TiempoRESUMEN
A case is presented of the ataxic variety of Creutzfeldt-Jakob disease with particular reference to the cerebellar cortex. The main features were loss of granule cells, subtotal in the vermis, severe in the lateral lobes, mild to moderate loss of Purkinje cells and preservation of tangential and basket fibres. The Purkinje cell dendrites showed malorientation and hypertrophy of the primary and secondary branches, the so-called "antler" or "staghorn" deformity. These findings indicate that remodelling of the dendritic tree may start early in the course of the disease even in adults, the total length of history in this case being eight months. They do not throw any additional light on the pathogenesis of the dendritic abnormalities, in particular on the controversy whether they are a non-specific response of the Purkinje cell to a variety of noxious agents or a reaction to partial deafferentation. The authors favour the latter hypothesis.