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F Scaravilli

Publications and source records attributed to F Scaravilli.

At least 19 recordsLinked to original sources
PubMed1995

Kearns-Sayre syndrome associated with mitochondrial DNA deletion or duplication: a molecular genetic and pathological study.

The neuropathological findings in 2 patients with Kearns-Sayre syndrome and mitochondrial DNA (mtDNA) rearrangements, one a predominant deletion and the other a predominant duplication, were remarkably similar, showing diffuse vacuolation of white matter. There were some of the pathological features of Leigh's syndrome in the spinal cord of the patient with a duplication. In the patient with a predominant deletion, rearranged mtDNA was undetectable in blood, spleen, and testis, and present in highest amounts in muscle and the brain, but relatively low in cerebellum, reflecting the ratio seen, albeit in much smaller amounts, in normal aged brains. MtDNA rearrangements in this patient were largely deletions or deletion dimers; duplicated mtDNA was present in only trace amounts in some tissues and there was none in skeletal muscle. The patient with a predominant duplication of mtDNA had higher amounts of rearranged mtDNA in blood (mainly duplicated) than muscle (mainly deleted). Correlation of these data with tissue dysfunction is probably complicated by the replicative behaviour of deleted, duplicated and normal mtDNA.

Adolescent↗
PubMed1995

AIDS-associated vacuolar myelopathy. A morphometric study.

The post-mortem pathology in 20 spinal cords of human immunodeficiency virus (HIV) infected patients with vacuolar myelopathy was quantified by evaluating (i) the intensity of myelin change, vacuolation and macrophage density; and (ii) the areas of white matter covered by each feature. Severity scores were constructed for (i) the anterior, lateral, and posterior white matter columns; (ii) each level of spinal cord; and (iii) the whole spinal cord [Cord Total and Cord Average Severity Scores (CTSS, CASS)]. Astroglial activation was scored separately. In 14 cords with mild-moderate vacuolar myelopathy (CASS = 23-259), macrophages were the most prominent pathological feature, and level severity scores were higher at mid-thoracic than cervical levels (P = 0.009). In six cords with severe vacuolar myelopathy (CASS = 396-614), vacuolation, demyelination and macrophages were equally evident and thoracic and cervical level severity scores were similar. The most severe lesions showed evidence of clearing of macrophages from the collapsed centres. A clinical lower limb score correlated with the anterior (P = 0.03) and lateral (P = 0.04) column total scores and with the CTSS (P = 0.04) in the nine patients who had had both myelopathy related disability and all cord levels available. There was no significant longitudinal gradient in score severity in the posterior, lateral or anterior columns and no evidence of a dying-back phenomenon. There was no evidence of Wallerian degeneration occurring as a primary process. Astroglial activation did not correlate with the severity or duration of the vacuolar myelopathy. Detection of HIV p24 antigen in the spinal cord related to the local presence of multinucleated giant cells and to antigen expression in the brain but not with the severity of vacuolar myelopathy. The pathology in vacuolar myelopathy appeared to start in the mid-low thoracic cord, with increasing rostral involvement as the disease became more severe. The relative prominence of macrophages in mild-moderate lesions suggests they may be involved early in the pathogenesis of vacuolar myelopathy.

Acquired Immunodeficiency Syndrome↗
PubMed1994

Development of cortical fibres into the gracile nucleus of the rat: an ultrastructural study.

A study was made on the development of cortical synapses in the gracile nucleus of rats using degeneration methods. A total of 46 animals, 1 adult and 45 neonates whose ages varied from 1 to 7 days, had the right somatosensory motor cortex destroyed. The survival period varied from 1 to 30 days. Identification of axonal terminals in the gracile nucleus was also achieved by tracing the cortical fibres of 1 adult rat using horseradish peroxidase-wheat germ agglutinin (HRP-WGA). Degenerating axodendritic and axosomatic terminals that originated from cortical fibres were seen in the adult animal which survived 2 days. Their origin was confirmed by the presence of HRP-WGA inside the terminals. Light or electron microscopic changes were not seen, and in particular, the gracile nucleus was not smaller than in the control adult animals which survived 30 days or in neonates which survived 8-30 days, consistent with the small component of cortifugal fibres believed to terminate in secondary sensory nuclei. In neonates that survived a shorter period, terminal degeneration was only seen in cases operated at 4 days and later, indicating that cortical axons do not synapse in the gracile nucleus until postnatal day 4. Our results provide further support for the existence of a period in which the fibres approach their target but do not penetrate it to form synaptic junctions during the growth of cortical axons toward their targets, since previous studies have demonstrated that cortical fibres persisting to adulthood decussate completely at the level of the medulla at 12-36 h after birth.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1992

A follow-up study of isolated cases of suspected Huntington's disease.

We reviewed 49 patients in whom a diagnosis of Huntington's disease (HD) seemed possible on clinical grounds, but who gave no history of definitely affected relatives. In 32 with the typical clinical features of HD (progressive chorea and dementia, postural instability, abnormal initiation of saccadic eye movements), the diagnosis was confirmed in 7 patients who had had autopsies, affected relatives were found in 5 others, and HD remained probable in a further 13 who were reexamined. In the 17 with a less typical clinical picture, a diagnosis of HD appeared most likely in 2; other causes for chorea such as cerebrovascular disease, neuroacanthocytosis, recrudescence of Sydenham's chorea, and drug-induced tardive dyskinesia could be invoked in the remainder. We conclude that the likelihood of HD in a patient with the typical clinical features of this disorder but no history of affected relatives is at least 75%, which for practical purposes implies a risk to their children hardly less than in familial HD. The most plausible explanations for seemingly sporadic patients with HD are nonpaternity and mild, late-onset disease that is overlooked by other family members.

Adult↗
PubMed1992

Hemiballism and chorea in a patient with parkinsonism due to a multisystem degeneration.

Dyskinesias associated with dopaminergic treatment in idiopathic Parkinson's disease (PD) can be indistinguishable from those arising spontaneously in other conditions involving degeneration of, or damage to, the basal ganglia. However, those due to levodopa treatment of PD disappear on cessation of therapy. We report a patient with a clinical diagnosis of PD who, on levodopa treatment, developed hemiballism and chorea that were originally thought to be drug induced. However, the dyskinesias persisted despite stopping levodopa. Postmortem analysis showed a multisystem degeneration.

Aged↗
PubMed1992

The pathology of the posterior root ganglia in AIDS and its relationship to the pallor of the gracile tract.

The spinal cord and the thoracic and lumbar posterior root ganglia (PRGs) of 14 HIV-positive men and 7 age- and sex-matched controls were studied by routine histology, morphometric analysis of the number of nodules of Nageotte (nN) and the diameters of sensory ganglion cells, immunohistochemistry and in situ hybridization. In 7 patients (2 of whom had evidence of cytomegalovirus ganglionitis) there were increased numbers of nN and diffuse, mild infiltration with CD45R+ T lymphocytes; no B lymphocytes were observed. Macrophages were increased in number in all cases. Whenever more than one ganglion was examined from the same patient, the appearances were similar in all. There was no alteration in the distribution of ganglion cell diameters. Changes in the spinal cord included vacuolar myelopathy (5 cases), HIV myelitis (1 case), microglial nodules (3 cases) and pallor of the gracile tracts (GTP) in 7 cases, in 6 of whom it co-existed with increased numbers of nN. Seven cases had no abnormalities, except the increase in number of macrophages in PRGs. In spite of a correlation between sensory nerve cell loss and GTP our findings suggest that other mechanisms, such as 'dying back' may contribute to the pathogenesis of GTP. Moreover, sensory disturbances were found most commonly in association with nerve cell loss; however, loss of sensory ganglion cells was not necessarily associated with evidence of sensory impairment.

Acquired Immunodeficiency Syndrome↗
PubMed1992

Detection of HIV proviral DNA in cortex and white matter of AIDS brains by non-isotopic polymerase chain reaction: correlation with diffuse poliodystrophy.

OBJECTIVE: (1) To determine whether detection of HIV proviral DNA sequences in the cerebral cortex correlates with the presence of pathological changes in this region, believed to contribute to the HIV-associated cognitive/motor complex. (2) To compare the frequency with which HIV infects cortical and subcortical regions of the brain. DESIGN: In vitro studies on HIV neurotoxicity suggest that HIV may be involved in the pathogenesis of cortical damage, recently defined as diffuse poliodystrophy (DPD) in AIDS. Previous detection of HIV antigen has localized HIV more frequently to subcortical than to cortical regions. It is not known whether HIV preferentially infects subcortical tissues or if viral expression varies in these two regions. METHODS: HIV antigen and proviral DNA sequences were detected in anterior frontal lobe tissues using immunohistochemistry (IHC) and the polymerase chain reaction (PCR), respectively. DPD was assessed by staining with antibodies against astrocytes (GFAP) and microglia/macrophages (HAM 56). RESULTS: HIV proviral DNA was detected in nine out of 15 cortical samples and in 10 out of 15 white matter samples, whilst HIV p24 antigen was localized to the cortex in three out of 15 and to the white matter in seven out of 15 cases. DPD was found in 10 cases, although in five a different aetiology may have been involved. However, DPD was present in eight out of the nine cases in which HIV proviral DNA was detected in the cortex. CONCLUSIONS: Using a non-isotopic PCR method, HIV was detected in the brains of more cases than would be expected on the basis of IHC detection, and was present in the cortex as frequently as in the white matter. HIV, together with other factors, may contribute to the pathogenesis of DPD.

AIDS Dementia Complex↗
PubMed1992

Varicella-zoster virus encephalitis in acquired immunodeficiency syndrome: report of four cases.

Four patients with acquired immunodeficiency syndrome, a 27-year-old female intravenous drug abuser and three males (two drug addicts aged 27 and 33 years and a 40-year-old homosexual) presented with a rapidly progressive encephalopathy. Two had generalized varicella-zoster virus skin infection, one had had a regressive thoracic zoster rash 7 months previously and one had no history of cutaneous eruption. Neuropathological examination revealed, in each case, multifocal necrotic changes with numerous, intranuclear Cowdry type A inclusion bodies in glial cells, endothelial cells, macrophages and neurons, within and around the lesions. These inclusion bodies were stained positively for varicella-zoster virus by immunocytochemistry and contained herpes virus nucleocapsids by electron microscopy. Molecular biology using the polymerase-chain-reaction method demonstrated viral genome. In one case, zoster-induced non-inflammatory vasculopathy involved medium sized leptomeningeal vessels and was associated with circumscribed areas of cortico-subcortical infarction. In another case, varicella-zoster virus encephalitis was associated with human immunodeficiency virus encephalitis and a secondary cerebral lymphoma. Multinucleated giant cells expressing human immunodeficiency virus proteins in their cytoplasm, were found in the lymphomatous deposits and in the varicella-zoster virus necrotic lesions. In these latter lesions, Cowdry type A inclusion bodies could be seen in the nuclei of some multinucleated giant cells confirming previous observations of MGCs co-infected by HIV and CMV, and supporting the hypothesis that DNA viruses interact with HIV, thus increasing its effect.

Acquired Immunodeficiency Syndrome↗
PubMed1992

Primary cerebral lymphoma: a study of 47 cases probed for Epstein-Barr virus genome.

AIMS: To determine the prevalence of Epstein-Barr virus genome in primary cerebral lymphomas occurring in the absence of immune suppression. METHODS: Forty eight consecutive patients with lymphomas restricted to the central nervous system were identified, all of whom had had neurosurgical biopsies performed at the National Hospitals for Neurology and Neurosurgery, London. Only five patients had some form of underlying immune deficiency; 43 were apparently normal. The tumours were studied with immunohistochemical markers and by in situ hybridisation, using a biotinylated probe to the internal repeat region of Epstein-Barr virus. RESULTS: All the lymphomas were B cell in origin. Tumours from the five immunosuppressed patients all showed hybridisation, as did two of the "spontaneous" tumours. CONCLUSIONS: This is the largest series of cerebral lymphomas so far probed for Epstein-Barr virus genome: as more are examined, it is suggested that a small proportion of the tumours from immunocompetent patients will also contain the virus.

B-Lymphocytes↗
PubMed1992

Neuroenteric cyst of the optic nerve: case report with immunohistochemical study.

A 36 year old man developed slowly progressive unilateral visual loss due to a cystic lesion of the intraorbital optic nerve. Pathologically the lesion was an epithelium lined cyst entirely within the atrophic nerve. The cyst lining consisted of columnar epithelium partly pseudostratified and ciliated with evidence of mucin secretion, and was immunoactive for cytokeratin but not glial fibrillary acidic protein. This lesion is considered to be similar to neuroenteric cysts that have been reported elsewhere in the nervous system, and the immunocytochemical results are consistent with a heterotopia derived from the primitive ectoderm of the stomatodeum.

Adult↗
PubMed1991

Differential neuropeptide expression after visceral and somatic nerve injury in the cat and rat.

The expression of neuropeptides galanin, vasoactive intestinal polypeptide (VIP) and substance P was compared after injury to somatic (sciatic, pudendal) and visceral (pelvic) nerves. Studies in normal rats and the mutant rat 'mutilated foot' suggested that galanin increases in sensory but not sympathetic fibres after sciatic nerve injury, while VIP appears to increase in both sensory and sympathetic fibres, and substance P to decrease in sensory fibres. A direct comparison of neuropeptide changes after somatic and visceral nerve injury was made in the cat dorsal sacral spinal cord, where both pudenal (somatic) and pelvic (visceral) afferents terminate. Four weeks after pudendal nerve transection in the cat there was an increase of VIP and galanin but decrease of substance P in the dorsal sacral cord, similar to the changes in lumbar dorsal cord after sciatic nerve section in the rat. In contrast, 4 weeks after pelvic nerve transection in the cat, galanin was unchanged in the ipsilateral dorsal sacral spinal cord, whereas VIP is known to decrease markedly and substance P to remain unchanged. There is thus differential peptide expression before and after injury in somatic and visceral systems, which may be regulated in part by the target organ. We have proposed that the neuropeptide changes occur in neurons that regulate development, maintenance and repair after injury, processes that may differ in somatic and visceral systems.

Animals↗
PubMed1991

Prominent cortical atrophy with neuronal loss as correlate of human immunodeficiency virus encephalopathy.

A 25-year-old homosexual AIDS patient presented with progressive cognitive, motor and behavioral disturbances consistent with HIV encephalopathy. CT scans demonstrated progressive diffuse brain atrophy. Neuropathology showed predominant cortical changes including severe neuronal loss corroborated by morphometry. Only minimal changes were found in the white matter and basal ganglia. Immunocytochemistry for HIV stained occasional microglial cells more markedly in the cerebral cortex. This suggests that HIV infection of the brain may cause predominant cortical nerve cell loss, and that HIV encephalopathy is not necessarily due to white matter lesions.

AIDS Dementia Complex↗