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PubMed1996

[A case of atypical progressive supranuclear palsy with degeneration of the fronto-pontine tracts, and without grumose degeneration of the dentate nucleus].

An autopsy case of progressive supranuclear palsy (PSP) with degeneration of the fronto-pontine tracts of the midbrain and pons, and without grumose degeneration of the dentate nucleus is reported. A 72-year-old woman was suffering from dysarthria and gait disturbance. Moderate dementia was noted and gradually worsened. Pyramidal and extrapyramidal signs and cerebellar ataxia were not observed. Eye movements were fully preserved. Brain CT showed cerebellar atrophy. Three years later, she was unable to stand or move, and became mutistic. At the age of 75, she died suddenly. The duration of her illness was approximately 4 years. Clinical diagnosis was LCCA (late cortical cerebellar atrophy). Neuropathological examination revealed gliosis of the deep layers of the cerebral cortex around the precentral gyrus, fronto-pontine tracts degeneration (posterior part of the anterior crus, genu and anterior part of the posterior crus of the internal capsule, cerebral peduncles of the midbrain, pontine base and pyramis of the medulla oblongata). Also, atrophy of the pons and marked degeneration of the superior colliculi and substantia nigra were observed. Neurofibrillary tangles (NFTs) and glial fibrillary tangles (GFTs) were found in the subcortical nuclei. These findings were almost consistent with PSP. However, the following differed from those of previously reported typical PSP cases: firstly, mild gliosis in the reticular formation of the midbrain; secondly, few NFTs in the pontine nuclei and superior colliculi and; thirdly, no grumose degeneration in the dentate nucleus. In addition, clinical symptoms of the present case are not consistent with PSP. Therefore, we concluded this case to be an atypical PSP both clinically and neuropathologically.

Aged↗
PubMed1978

Systems-matching by degeneration. I. A quantitative electron microscopic study of the generation and degeneration of retinal ganglion cells in the chicken.

The total number of optic nerve fibers of the chicken was determined at twenty sequential developmental stages from incubation day 5 to 104 days after hatching. It was found that the total number of optic nerve fibers increases from 4400 on incubation day 5 to about 4.0 million on incubation days 10 and 11. Thereafter, it decreases to a final value of about 2.4 million by incubation day 18 and remains constant from that time on until adulthood. Thus, 40% of optic fibers degenerate. Degenerating ganglion cells in the retina are first detectable by incubation day 9. Initially degenerating cells are located mainly in the central retina, but on subsequent days they can be found predominantly in peripheral zones. It is postulated that cell death occurs because of competition for adequate arborization space. If more retinal afferent fibers arrive than tectal termination sites are available, supernumerary fibers may degenerate. By degeneration the two systems retina and optic tectum, are matched in size.

Age Factors↗
PubMed1999

Can secondary degeneration accelerate the formation of neurofibrillary tangles? A case of hemispheric infarction showing asymmetric degeneration of the substantia nigra, red nuclei, inferior olivary nuclei and dentate nuclei with concomitant changes of progressive supranuclear palsy.

A case of hemispheric infarction involving the territory of the right middle cerebral artery and the thalamus showed conspicuous asymmetric degeneration in the substantia nigra, red nuclei, inferior olivary nuclei and dentate nuclei with concomitant changes of progressive supranuclear palsy (PSP). The right substantia nigra and red nucleus showed loss of neurons and proliferation of astrocytes. The right olivary nucleus was hypertrophic, while the neuronal loss and astrocytosis in the dentate nucleus were predominant on the contralateral side. Modified Gallyas-Braak staining revealed the extensive distribution of neurofibrillary tangles (NFTs), threads and intraglial argyrophilic structures in the globus pallidus, subthalamic nuclei, cerebral cortex and dentate nuclei, as well as in the affected brain stem nuclei, with a distinct predominance on the affected side. In this case, the one-sided predominance of the extended degeneration in these brain stem and cerebellar areas is considered, in addition to the PSP changes, to be due to secondary retrograde degeneration via the nigrostriatal and dentato-rubro-thalamic pathways following the hemispheric infarction, and to also be the result of disruption of the dentato-olivary fiber connections. In addition, because of the predominant distribution of NFTs on the more degenerated side, it is surmised that the formation of NFTs may be accelerated by secondary degeneration.

Aged↗
PubMed1975

Striato-nigral degeneration. Report of a case with an unusually short course and multiple system degenerations.

A 50-year-old white woman with an 8-month history of Parkinson's syndrome which did not respond to levodopa therapy was found on pathological examination to have the topographical lesions of striato-nigral degeneration. In addition to those characteristic lesions, an associated degeneration of the optic pathways, from the level of the optic nerve to the geniculo-collicular fibers, of the corticospinal tract and of the olivo-dentate axis, were found. While offering further evidence for the concept of "multiple system degeneration", no pathogenetic relationship either to previous cases of striato-nigral degeneration or to other multiple system degenerations is implied.

Brain↗
PubMed2005

A novel rabbit model of mild, reproducible disc degeneration by an anulus needle puncture: correlation between the degree of disc injury and radiological and histological appearances of disc degeneration.

STUDY DESIGN: An in vivo study to radiographically and histologically assess a new method of induction of disc degeneration. OBJECTIVE.: To establish a reproducible rabbit model of disc degeneration by puncturing the anulus with needles of defined gauges and to compare it to the classic stab model. SUMMARY OF BACKGROUND DATA: New treatment approaches to disc degeneration are of great interest. Although animal models for disc degenerative disease exist, the quantitative measurement of disease progression remains difficult. A reproducible, progressive disc degeneration model, which can be induced in a reasonable time frame, is essential for development of new therapeutic interventions. METHODS: The classic anular stab model and the new needle puncture model were used in the rabbit. For the needle puncture model, 3 different gauges of needle (16G, 18G, and 21G) were used to induce an injury to the disc to a depth of 5 mm. Radiographic and histologic analyses were performed; magnetic resonance images were also assessed in the needle puncture model. RESULTS: Significant disc space narrowing was observed as early as 2 weeks after stabbing in the classic stab model; there was no further narrowing of the disc space. In the needle puncture model, all needle sizes tested induced a slower and more progressive decrease in disc height than in the classic stab model. The magnetic resonance imaging supported the results of disc height data. CONCLUSIONS: The needle puncture approach, using 16G to 21G needles, resulted in a reproducible decrease of disc height and magnetic resonance imaging grade. The ease of the procedure and transfer of the methodology will benefit researchers studying disc degeneration.

Animals↗
PubMed1983

Hereditary multisystemic degeneration with unusual combination of cerebellipetal, dentato-rubral, and nigro-subthalamo-pallidal degenerations.

An autopsy case of a 51-year-old housewife with dominantly inherited ataxia is reported. Pathologic examination revealed an unusual combination of systemic degenerations: spinocerebellar tracts, pontine basis and middle cerebellar peduncles, dentato-rubral and nigro-subthalamo-pallidal systems, upper and lower motor neurons, ascending sensory system, and optic tracts. The inferior olive and cerebellar cortex showed only a slight change. The combination of the dentato-rubral with nigro-subthalamo-pallidal degenerations in a case with cerebellipetal systemic degeneration was particularly striking. Furthermore, combined degeneration of the ocular motor nuclei, vestibular nuclear group, perihypoglossal nuclei, fastigial nucleus, medial longitudinal fasciculus, and vestibulospinal tracts occurred. According to recent experimental results, these lesions were restricted precisely to the anatomophysiologically interrelated system for the control of eye movement. The present case is considered an example of systemic degeneration as a pathologic basis for ophthalmoplegia.

Brain Diseases↗
PubMed1997

Cortical degeneration in progressive supranuclear palsy. A comparison with cortical-basal ganglionic degeneration.

We report 3 patients with progressive supranuclear palsy (PSP) who developed limb apraxia, focal dystonia, and arm levitation late in the course of the disease. Neuropathological examination revealed cortical degeneration in addition to the characteristic pathological findings of PSP. Semiquantitative comparative histological and immunohistological studies of the neocortex of these patients as well as 5 cases of classical PSP and 4 cases of cortical-basal ganglionic degeneration (CBGD) revealed a distinctive form of cortical degeneration in PSP. The cortical degeneration was often circumscribed and confined to premotor and motor cortex. It was characterized by neuronal loss and gliosis. Swollen neurons were only rarely observed in neocortex of PSP cases in contrast with CBGD, where they were abundant. Neuronal and glial tau as well as tau immunoreactive threads were seen in both PSP and CBGD, but were more abundant in CBGD. The appearance of tau reactive astrocytes also differed in both disorders; tufted astrocytes were seen exclusively in PSP, while typical annular astrocytic plaques were confined to CBGD. These observations indicate that cortical degeneration occurs in PSP and may be associated with atypical clinical manifestations that lead to diagnostic difficulties.

Aged↗
PubMed2001

Mutations in ABCR (ABCA4) in patients with Stargardt macular degeneration or cone-rod degeneration.

PURPOSE: To determine the spectrum of ABCR mutations associated with Stargardt macular degeneration and cone-rod degeneration (CRD). METHODS: One hundred eighteen unrelated patients with recessive Stargardt macular degeneration and eight with recessive CRD were screened for mutations in ABCR (ABCA4) by single-strand conformation polymorphism analysis. Variants were characterized by direct genomic sequencing. Segregation analysis was performed on the families of 20 patients in whom at least two or more likely pathogenic sequence changes were identified. RESULTS: The authors found 77 sequence changes likely to be pathogenic: 21 null mutations (15 novel), 55 missense changes (26 novel), and one deletion of a consensus glycosylation site (also novel). Fifty-two patients with Stargardt macular degeneration (44% of those screened) and five with CRD each had two of these sequence changes or were homozygous for one of them. Segregation analyses in the families of 19 of these patients were informative and revealed that the index cases and all available affected siblings were compound heterozygotes or homozygotes. The authors found one instance of an apparently de novo mutation, Ile824Thr, in a patient. Thirty-seven (31%) of the 118 patients with Stargardt disease and one with CRD had only one likely pathogenic sequence change. Twenty-nine patients with Stargardt disease (25%) and two with CRD had no identified sequence changes. CONCLUSIONS: This report of 42 novel mutations brings the growing number of identified likely pathogenic sequence changes in ABCR to approximately 250.

ATP-Binding Cassette Transporters↗
PubMed1994

Decreased opsin mRNA and immunoreactivity in progressive rod-cone degeneration (prcd): cytochemical studies of early disease and degeneration.

Opsin mRNA level and immunoreactivity were examined by in situ hybridization and immunocytochemistry in normal and progressive rod cone degeneration (prcd)-affected dogs. In situ hybridization used 35S- and/or 3H-labeled bovine opsin cRNA probes; immunocytochemistry used six monoclonal mouse anti-bovine opsin antibodies (MAb1) that are specific to different regions of the N-terminal, loop v-vi and the C-terminal domains. Optimal labeling and histological resolution at the single cell level were achieved with semi-thin sections of DGD wax-embedded tissues; it was possible to correlate the cytochemical observations with the disease staging in topographically defined regions that exhibited different disease severity. In early disease (stages 0-1), opsin mRNA levels and immunoreactivity were normal. During the transition from disease to degeneration (stage 2), however, opsin mRNA was reduced sharply; it then rapidly became undetectable in late stages of degeneration (stages 3, 4). Reduction of immunoreactivity was seen with all the MAbs in stages 2 and 3, but the degree of reduction varied remarkably in different regions of the protein molecule; immunoreactivity was reduced more in the cytoplasmic regions, particularly in the phosphorylation sites and the far end of the C-terminal domain. In contrast, the epitopes of the N-terminal domain that are located in the intradiscal compartment were better preserved. It is noteworthy that, in stages 2 and 3, many rod cells still survived despite the decrease in the mRNA level and immunoreactivity. The results indicate that early disease in prcd-affected rods is not initiated by a reduction of opsin mRNA or the protein quantity. However, opsin expression disappears in early degeneration and before cell death. The differences in immunoreactivity with disease may result either from alterations in the protein structure or configuration, or from selective loss of epitopes located in the cytoplasmic domains of the molecule.

Animals↗
PubMedDate not supplied

Sequential events of degeneration and synaptic remodelling in the viper optic tectum following retinal ablation. A degeneration, radioautographic and immunocytochemical study.

The ultrastructural changes taking place in the retino-recipient layers of the viper optic tectum were examined between 5 and 122 days after retinal ablation. The initial degeneration of retinotectal terminals proceeds at widely different rates and is characterized by a marked degree of polymorphism in which a number of different patterns can be discerned. In the final stages of degeneration, either both the degenerating bouton and the distal portion of the postsynaptic element are engulfed by reactive glia, or, more frequently, only the degenerating terminal is eliminated and the postsynaptic differentiation remains. The free postsynaptic differentiations are reoccupied predominantly by boutons containing pleiomorphic vesicles and which are for the most part gamma-aminobutyric acid (GABA)ergic, thus forming heterologous synapses; less frequently these sites are occupied by boutons of the ipsilateral visual contingent to form homologous synapses. These two processes, both of which depend on terminal axonal sprouting, take place within the first 3 postoperative months. They are followed by a decrease in the number of heterologous synapses and a concurrent increase in the number of homologous synapses newly formed by optic boutons generated by collateral preterminal sprouting of ipsilateral retinotectal fibres. The data suggest that partial deafferentation of the optic tectum induces a transitory GABAergic innervation of free postsynaptic sites prior to the restoration of new retinal synaptic contacts.

Afferent Pathways↗
PubMed1998

Alteration of enzymatic activities implicating neuronal degeneration in the spinal cord of the motor neuron degeneration mouse during postnatal development.

Oxidative stress is suggested as a significant causative factor for pathogenesis of neuronal degeneration on spinal cord of human ALS. We measured some enzymic activities implicating neuronal degeneration process, such as cytochrome c oxidase (CO), superoxide dismutase (SOD), and transglutaminase (TG) in spinal cord of an animal model of ALS, motor neuron degeneration (Mnd) mouse, a mutant that exhibits progressive degeneration of lower spinal neurons during developmental growth, and compared them with age-matched control C57BL/6 mice. CO activity in Mnd spinal cord decreased during early postnatal period, while SOD activity reduced in later stage. In Mnd tissue, TG activity in lumbar cord was increasing during early stage, but tended to decline in later period gradually. These biochemical alterations became evident prior to the appearance of clinical motor dysfunction which were observed in later stages of development in Mnd spinal cord.

Aging↗
PubMed1978

Time course of degeneration of short and long postganglionic sympathetic nerve fibres and effect of pentobarbitone and colchicine on degeneration.

1 The time-course of degeneration of sympathetic nerves was investigated by measurement of the endogenous noradrenaline content of the rat vas deferens, submandibular gland and spleen following sympathectomy.2 Extirpation of the hypogastric plexus, superior cervical ganglion and coeliac plexus under pentobarbitone anaesthesia caused 50% depletion of the noradrenaline content of the vas deferens, submandibular gland and spleen in approximately 16, 19 and 21 h, respectively.3 Under pentobarbitone anaesthesia, proximal sympathectomy (i.e., close to the end organ) produced depletion of the noradrenaline content of the submandibular gland 8 h earlier than that caused by distal sympathectomy. Under ether anaesthesia, the time difference in obtaining the same degree of depletion after the two procedures of sympathectomy was only 2 hours.4 Removal of the superior cervical ganglion under ether anaesthesia resulted in almost complete depletion of noradrenaline content of the submandibular gland in 17 h, whereas when a similar operation was performed under pentobarbitone anaesthesia, nearly 24 h were required for the same degree of depletion. Similarly, the noradrenaline content of the spleen was depleted 4 h earlier if the coeliac plexus was ablated under ether as compared to pentobarbitone anaesthesia.5 Local application of colchicine (10 mg/ml, 30 min) to postganglionic sympathetic nerve axons had no effect on the noradrenaline content of the submandibular gland up to 24 hours. However, removal of the superior ganglion following colchicine application considerably slowed the depletion of the noradrenaline content of the submandibular gland (at 17 and 20 h after ganglionectomy, 10 and 20% depletion, respectively, in the experimental gland, as compared to 70 and 80%, respectively, in the control gland).6 To explain the results, it is proposed that injury to the sympathetic nerves at the site of sectioning triggers a signal (messenger substance) which travels down to the nerve endings to produce degeneration. Thus, the length of the extrinsic nerve fibre influences the time course of degeneration by changing the rate of transport of the messenger substance, whereas pentobarbitone and colchicine alter the synthesis and/or transport of the messenger substance to modify the time-course of degeneration.

Animals↗
PubMed1985

[Cerebellar degeneration in chronic alcoholism: with special reference to an autopsied case showing the restricted form of cerebellar cortical degeneration (Victor)].

The brains of 8 patients with chronic alcoholism were neuropathologically examined. The findings obtained in the cerebellum of case 1 (male, aged 52) were in agreement with the restricted form of cerebellar cortical degeneration which was described by Victor et al (1958). The clinicopathological report on the cerebellar degeneration of this type was very rare in Japan. The cerebellar changes were more pronounced in the anterior vermis than in the posterior vermis and hemisphere. Furthermore, some old lesions of Wernicke's encephalopathy were found in this brain. 7 other cases showed very mild cerebellar degeneration. Partial loss of Purkinje cells was found near the tops of cerebellar folia. But their distribution and intensity had no individual variation and there was no tendency that the anterior vermis was more affected. This fact suggests that the alcoholic cerebellar degeneration may have some other cause than the direct toxic effect of ethylalcohol or its metabolites. The etiology of this disease was discussed with reference to thiamine deficiency and mal-nutrition.

Adult↗
PubMed1993

[Wallerian degeneration of the cortico-descending tract in the cerebral peduncle following a supratentorial cerebrovascular lesion detected by MRI--the relationship between Wallerian degeneration at the center of the cerebral peduncle and functional recovery of paresis].

We studied Wallerian degeneration of the cortico-descending tract in the cerebral peduncle following a supratentorial cerebrovascular lesion by MRI. A total of 57 patients with palsy following a supratentorial cerebrovascular lesion were prospectively studied. Wallerian degeneration was detected as a high signal intensity (HSI) in 37 patients between 70 days and 100 days after the onset, but not detected in the remaining 27 patients. Patient with an HSI in all area of the cerebral peduncle had a large lesion involving the hemisphere. Patient with an HSI at the center of the cerebral peduncle had a lesion confined to the paracentral gyrus, precentral gyrus, corona radiata or posterior limb of the internal capsule. Patient with an HSI at the lateral side of the cerebral peduncle had a lesion of parietal lobe or temporal lobe which spares the corticospinal tract originating from the paracentral gyrus, precentral gyrus, corona radiata or posterior limb of the internal capsule. These findings suggest that an HSI at the center of the cerebral peduncle may reveal Wallerian degeneration of the corticospinal tract, and an HSI at the lateral side of the cerebral peduncle may show Wallerian degeneration of the corticopontine tract. The functional recovery of paresis was poor in all patients with an HSI at the center of the cerebral peduncle, while it was good in all patients without an HSI in that region.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed2003

The volume and morphology of chondrocytes within non-degenerate and degenerate human articular cartilage.

OBJECTIVE: Cartilage swelling is an early event in osteoarthritis (OA). However, the response of chondrocytes to increased tissue hydration is unknown. This work studied the volume and morphology of living in situ human chondrocytes as a function of cartilage degeneration. METHODS: The tibial plateaus from knee joints of 40 patients were obtained following above-knee amputations or knee arthroplasty, and degree of cartilage degeneration from 0 (non-eroded) to 3 (extensive fibrillations) was assessed using several criteria. In situ chondrocytes were labeled with fluorescent indicators (calcein for living cells, propidium iodide for dead cells) permitting the quantification of volume and visualisation of morphology of cells within the cartilage zones by confocal scanning laser microscopy (CLSM). RESULTS: Chondrocyte volume within superficial and mid-zones, but not of deep zone cells, increased significantly (P<0.05 and P<0.02, respectively; one-way analysis of variance), with degree of cartilage hydration and degeneration. The volume increase ( approximately 90% for mid-zone chondrocytes, grade 3 cartilage) was greater than that which might occur following loss/excision of sub-chondral bone (<15% swelling). The CLSM technique utilised here revealed that approximately 40% of chondrocytes within all cartilage grades exhibited at least one cytoplasmic processes of <8 microm. The presence of these processes did not indicate a cell body of larger volume than cells without processes, and did not contribute to cell volume. CONCLUSIONS: The volume of in situ chondrocytes within the superficial and mid-zones increased with cartilage degeneration. Cell swelling was greater than that expected from the increased hydration in OA, suggesting that an increase in chondrocyte volume might play a role in the changes to matrix metabolism occurring in OA.

Aged↗
PubMed2000

Expression of Bcl-2 protects against photoreceptor degeneration in retinal degeneration slow (rds) mice.

The retinal degeneration slow or rds gene encodes rds/peripherin, an integral membrane glycoprotein in the outer segments of rod and cone photoreceptors. Mice homozygous for a null mutation in rds fail to develop outer segments and undergo subsequent degeneration of photoreceptors by the apoptotic pathway. Mutations in the human RDS gene are responsible for several forms of inherited blindness including autosomal-dominant retinitis pigmentosa and macular degeneration. Here, we examined the effects of ectopic Bcl-2 expression in transgenic photoreceptors on the rate of retinal degeneration in rds mutant mice. We observed an approximately twofold preservation of photoreceptors compared with nontransgenic rds mutant mice at 3 months. Immunoblot analysis showed similar levels of Bcl-2 in 2-, 3-, and 4-week-old transgenic mice. Expression of Bcl-2 in the rds mouse did not lead to outer segment formation and did not induce cell death. These results suggest that Bcl-2 expression may be an effective therapeutic strategy in humans with mutations in RDS or other genes that affect the integrity of photoreceptor outer segments.

Animals↗
PubMed1988

Paraneoplastic cortical cerebellar degeneration. A neuropathological study of an autopsy case in comparison with cortical cerebellar degeneration in alcoholics.

A case is described of paraneoplastic cortical cerebellar degeneration in a patient with a small cell carcinoma of the lung. Following therapy, clinical improvement of cerebellar ataxia had been observed. The most severe degeneration was found in the superior aspects of the vermis and in the anterior and simple lobes as well as in the inferior aspects of the hemisphere. In addition to this distribution of degenerative lesions, uneven loss of Purkinje cells was apparent. Such distribution patterns in this case were apparently compatible with those of alcoholic cortical cerebellar degeneration (ACD), although the lesions were less severe than in ACD. Furthermore, dendritic changes in the Purkinje cells including loss of the spiny branchlets, focal swelling of the dendrites, and disappearance of secondary and tertiary branches were remarkable. It is noteworthy that these cells showed various stages of degeneration before cell loss occurred. These data suggest that the degree of vulnerability varies among Purkinje cells, and that this could be related to the uneven loss of these cells. It is proposed that, although this case and cases of ACD have both similarities and differences in their neuropathological aspects, it is apparent that both conditions have some common morphopathogenetic factor.

Alcoholism↗
PubMed1978

[The macular fatty degeneration of the peripheral retina a variety of the snail track degeneration (author's transl)].

A previously undescribed form of snail-track degeneration with scattered flecks was found in three eyes with absolute glaucoma. Light- and electron-microscopic examination of these lesions in the retinal periphery revealed atrophy and gliosis with massive accumulation of fat within the astrocytes and Müller's cells. It was not possible to explain the patchy distribution of the lesions. The fatty change in the macroglia is believed to indicate 'in situ breakdown' of slowly atrophying retina. Morphologic and pathogenetic similarities suggest that all forms of snail-track degeneration with snowflakes represent nonspecific fatty degeneration of the retina.

Adult↗