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Biomedical subjects

G C Guazzi

Publications and source records attributed to G C Guazzi.

At least 37 records · Page 2Linked to original sources
PubMed1996

An unusual type of primary cerebral hemihypotrophy with signs of dysfunctional neuronal migration.

We describe the neuropathological features of a complex brain malformation characterized by cerebral hemihypotrophy with ipsilateral lissencephaly, periventricular nodular heterotopia and macrogyria. The contralateral hemisphere showed only slight alterations of the gyral pattern and a limited periventricular gray matter heterotopia. The clinical picture of the patient, who died at the age of 15 years, consisted of severe oligophrenia, intractable seizures and left hemiparesis. We discuss the nosological status of this neuronal migration disorder of apparently unknown origin.

Adolescent↗
PubMed1996

Ataxia-telangiectasia: somatosensory, brainstem auditory and motor evoked potentials in six patients.

Six patients with ataxia-telangiectasia were given neurophysiological examinations. The patients had progressive sensorimotor axonal neuropathy that had begun at about age eight years. Brainstem auditory evoked potentials (BAEPs) showed central alternations in two of four cases. Somatosensory (BAEPs) and motor evoked potentials (MEPs) were altered in four of five cases. In the advanced stage of the disease the neurophysiological findings, except BAEPs and MEPs, resembled those in Friedreich's ataxia. MEP and BAEP results may therefore be useful for differential diagnosis.

Adolescent↗
PubMed1996

Autosomal recessive paraparesis with amyotrophy of hands and feet and white matter lesions.

We report two siblings with a hitherto undescribed syndrome of autosomal recessive spastic paraparesis accompanied by amyotrophy of hands and feet, and mental deterioration. Laboratory tests showed signs of lower motoneuron involvement in the four limbs, more accentuated in the distal regions. Brain MR showed bilateral symmetrical white matter lesions. We discuss the nosological status of this syndrome in relation to other similar forms of "complicated" spastic paraparesis.

Adult↗
PubMed1996

Localization of merosin in the normal human brain: implications for congenital muscular dystrophy with merosin deficiency.

A particular form of congenital muscular dystrophy with merosin deficiency has recently been described. Magnetic resonance imaging has shown that affected children show brain abnormalities. We investigate the localization of merosin in the normal human brain by immunohistochemistry. Other organs, such as the kidney, lung and liver, were also included in this study. We show that in the normal central nervous system merosin is localized in the basement membrane of blood vessels. No expression of merosin was found at the level of the liver and lungs, whereas the glomerular mesangial matrix of the kidney was intensely positive. These results suggest that merosin deficiency in the basement membrane of blood vessels in the central nervous system could play an important role in the physiopathology of brain abnormalities found in children affected by the congenital muscular dystrophy associated with merosin deficiency. Furthermore, the potential absence of merosin in the glomerular mesangial matrix of the kidney suggests a multi-system involvement.

Adult↗
PubMed1995

Ultrastructure and immunoreactivity of dystrophic axons indicate a different pathogenesis of Hallervorden-Spatz disease and infantile neuroaxonal dystrophy.

An immunohistochemical and ultrastructural analysis of dystrophic axons (DAs) in the brain and peripheral nerve of a patient with familial infantile neuroaxonal dystrophy (INAD) and in the brain of a patient with familial Hallervorden-Spatz Disease (HSD) revealed prevalent membrano-tubular or granulo-vesicular profiles with a graded pattern of evolution in INAD, while dense bodies, vesicles and amorphous material were present in HSD. DAs immunoreactivity with tai-protein and 200 kDa-neurofilament antibodies was stronger in HSD than in INAD. In both cases immunohistochemistry was positive for ubiquitin and negative for beta-tubulin and beta-amyloid. Distinct ultrastructural features and immunoreactivity pattern of cytoskeletal components suggest different pathogenetic mechanisms.

Axons↗
PubMed1995

Sequence analysis of mitochondrial DNA in a new maternally inherited encephalomyopathy.

A heteroplasmic insertion of a 9-bp tandem repeat element was detected in the mitochondrial DNA of the maternal members of a large family. The mutation was contained within the non-coding region between the genes specifying subunit II of cytochrome c oxidase and tR-NA(Lys). The proband and most of his maternal relatives were affected by a late-onset mitochondrial encephalomyopathy of variable severity, characterized by a unique combination of symptoms. Extensive screening of a large series of DNA samples, collected from unrelated normal individuals as well as patients affected by different neurological disorders, consistently failed to detect the 9-bp insertion, with two exceptions: a patient suffering from a syndrome virtually identical to that described in our original family and a child affected by bilateral striatal necrosis, a disorder which has been attributed to impairment of mitochondrial oxidative phosphorylation. These considerations suggest that the 9-bp insertion is pathogenic and that the region affected by the mutation may play a previously unsuspected functional role in mtDNA gene expression.

Aged↗
PubMed1995

Serum anti-brain endothelium antibodies and cognitive assessment in patients with Binswanger's encephalopathy.

The pathogenic mechanism underlying the vascular changes in Binswanger's encephalopathy (BE) is unknown. To test whether alterations of the humoral immunity may lead to endothelium damage, we analyzed serum levels of anti-brain endothelium antibodies (ABEA) (IgG and IgM) in 16 BE patients, 19 subjects with ischemic vascular disease without mental deterioration and 18 normal healthy subjects. ABEA IgM were found elevated in 1/16 (6%) BE patients and in 4/19 (21%) patients with cerebrovascular diseases; an increase in ABEA IgG was found in 6/16 (38%) BE patients and in 7/19 (37%) cerebrovascular patients. Association with anti-cardiolipin antibodies (IgG and/or IgM) was found in 50% of BE patients with elevated ABEA and only 10% of those with no increase, whereas high titres of anti-neurofilament antibodies (1:10,000) were detected in 40% and 71% respectively. In BE, ABEA IgG but not IgM showed a trend, although not significant, towards a correlation with the duration of the disease (rs = 0.47; p = 0.07) and significantly correlated with the cognitive function as assessed by the Mini mental state (MMS) score (rs = 0.56; p = 0.02). Higher mean values of the MMS score were found in BE patients with elevated ABEA than in those without (p = 0.04). This difference was not due to language disorders neither to an association with stroke risk factors or anti-neurofilament antibodies. However, there were no significant differences in MMS scores between cerebrovascular patients with ABEA and those without. A "neuro-protective" role is hypothesized for the ABEA in the development of dementia in BE.

Aged↗
PubMed1995

Early-onset benign limb-girdle myopathy with contractures and facial involvement affecting a father and daughter.

We describe a father and daughter with early-onset benign limb-girdle myopathy and contractures of elbows and hands, resembling Bethlem disease. Muscle biopsy showed a pattern of dystrophy with non specific mitochondrial changes. In both patients there was unusual facial muscle weakness. We discuss the nosologic position of Bethlem myopathy and suggest that facial involvement may be an additional feature of this disease.

Adenosine Triphosphatases↗
PubMed1995

Association of polyclonal anti-GM1 IgM and anti-neurofilament antibodies with CSF oligoclonal bands in a young with amyotrophic lateral sclerosis.

INTRODUCTION: The significance of the association of motor neuron syndromes with anti-GM1 antibodies remains unclear. We report the immunological study of a juvenile case of amyotrophic lateral sclerosis (ALS). MATERIALS AND METHODS: Serum anti-Gm1 and anti-neurofilament antibodies were assayed by ELISA and western blotting and cerebrospinal fluid (CSF) isoelectrofocusing was performed. Immunocytochemical studies were carried out with the patient's serum and CSF on human brain and spinal cord sections. RESULTS: Serum polyclonal IgM anti-GM1, anti-neurofilament antibodies and CSF oligoclonal bands were detected. Furthermore, an in vitro production of anti-GM1 IgM was demonstrated. Immunocytochemical studies showed cytoplasm motor neuron immunostaining, due to both IgG and IgM, that substantially decreased after immunoabsorption of the serum with bovine neurofilament proteins but not with GM1-containing liposomes. No immunostaining was obtained with CSF. Immunosuppressive treatment with cyclophosphamide and two cycles of plasma exchanges lowered anti-GM1 antibody levels, but did not determine any clinical improvement. CONCLUSION: To our knowledge, this is the first report of ALS, associated with circulating levels and in vitro production of polyclonal IgM anti-GM1, anti-neurofilament antibodies and CSF oligoclonal bands. These findings suggest the occurrence in our patients of an autoimmune process that could be involved in the pathogenesis of ALS.

Adult↗
PubMed1995

Motor evoked potentials by magnetic stimulation in hereditary and sporadic ataxia.

We report the study of motor evoked potentials by magnetic stimulation in 26 subjects with hereditary or sporadic ataxia. The subjects included 15 cases of late onset cerebellar ataxia (12 classified as olivopontocerebellar atrophy (OPCA), 3 as spinocerebellar atrophy (SCA)) and 11 cases of early onset cerebellar ataxia (4 Friedreich's ataxia (FA) and 7 unclassifiable in Friedreich's ataxia (NFA)). All subjects with FA and SCA had delayed central motor conduction times, more accentuated in corticospinal tracts directed to lumbar motoneurons. A similar but less marked slowing was observed in about half of the subjects with OPCA and NFA. In the last two groups the anomalies are more frequent in hereditary than in sporadic forms.

Adolescent↗
PubMed1994

Intrathecal synthesis of anti-myelin basic protein IgG in HIV-1+ patients.

Human immunodeficiency virus type 1 (HIV-1)-infected individuals frequently develop a broad spectrum of neurological syndromes, classified as HIV-1-associated cognitive/motor complex. Diffuse demyelination of hemispheric white matter is a commonly observed in HIV-1 infected brain, but the events leading to myelin destruction are still obscure. Since oligodendrocyte infection by HIV-1 is not proven as yet, myelin damage in HIV-1 infection may result from indirect mechanisms such as the excessive release of myelinotoxic substances or the triggering of autoimmune responses directed to myelin constituents. To verify the latter hypothesis, we searched for elevated anti-myelin basic protein (MBP) IgG levels in the cerebrospinal fluid (CSF) and serum of 25 patients with HIV-1 infection, 12 with multiple sclerosis (MS), and 9 with non-inflammatory neurological diseases (NIND). CSF, but not serum, anti-MBP IgG levels were more frequently elevated in HIV-1+ (16/25, 64%) than in MS (3/12, 25%) or NIND (0/9) patients. By using the anti-MBP IgG index, the anti-MBP IgG antibody specificity index (ASI), and the search for anti-MBP oligoclonal IgG, we ascertained that anti-MBP IgG were produced within the CNS in 13 of 25 (52%) HIV-1+, in 6 of 12 (50%) MS, and in none of NIND patients. The incidence of increased CSF anti-MBP IgG levels was higher among HIV-1+ patients at stage II-III (4/4, 100%) or at stage IV B (7/9, 78%) than among those at stage IV C-IV D (5/12, 42%). Although our data indicate that intrathecal anti-MBP IgG may occur early during HIV-1 infection and that they are more common in patients with HIV-1-associated cognitive/motor complex, the possible demyelinating role of these antibodies remains to be demonstrated.

AIDS Dementia Complex↗
PubMed1994

Cerebrotendinous xanthomatosis (van Bogaert-Scherer-Epstein disease): CT and MR findings.

PURPOSE: To describe the CT and MR findings in the brain and spinal cord of patients with cerebrotendinous xanthomatosis and to seek possible correlations between clinical, biochemical (cholestanol levels), and neuroimaging findings. METHODS: Ten patients with well-defined clinical and biochemical diagnoses of cerebrotendinous xanthomatosis were examined. Brain CT was performed in eight cases. In all patients MR was obtained using spin-echo and gradient-echo sequences. In eight patients spine MR was also performed. RESULTS: Neuroradiologic findings included diffuse cerebral and cerebellar atrophy. In half the cases, atrophy of the brain stem and corpus callosum was also found. In the majority of patients cerebellar bilateral focal lesions and mild white matter signal alterations were present. Spinal cord MR did not show signal abnormalities or atrophy. CONCLUSIONS: We found cranial alterations in patients with severe neurologic impairment, but there was no correlation with cholestanol plasma levels. No spinal cord abnormalities were present.

Adult↗
PubMed1994

Eosinophilia myalgia syndrome: absence of immunoglobulin reactivity suggests a cellular rather than humoral mechanism.

The idiopathic disorder Eosinophilia Myalgia Syndrome (EMS), characterized by peripheral eosinophilia, myalgia and frequently fasciitis, can be triggered by ingestion of some commercial preparations of L-Tryptophan. Activated T-lymphocytes and macrophages are involved in the pathogenesis of EMS. We investigated immunohistochemically the potential role of immunoglobulins and of the terminal C5b-9 complement factor (membrane attack complex) in EMS. We found no evidence for direct involvement of immunoglobulins. However, membrane attack complex immunoreactivity was present in vessel walls in EMS, but completely absent in controls. These observations suggest that the fasciitis in EMS involves a cellular rather than a humoral reaction and that complement activation could be of importance.

Adult↗
PubMed1993

Involvement of peripheral sensory fibers in amyotrophic lateral sclerosis: electrophysiological study of 64 cases.

We report electrophysiological findings of conduction along peripheral sensory fibers in 64 patients with amyotrophic lateral sclerosis. Distribution of the values of action potential amplitudes and conduction velocities of peripheral afferent fibers were significantly lower than in normal age-matched controls. Sensory action potential amplitudes (SAPas) were more affected than sensory conduction velocities (SCVs). When single patients were considered, SAPas were slightly but significantly reduced in 22% of the cases (median nerve 17%, ulnar nerve 11%, and sural nerve 22%). A parallel decrease in SCVs and MCVs in 14 patients in whom the study was repeated over a period of time was also found. All these electrophysiological findings are due to progressive neuronopathy of peripheral sensory fibers. A pathogenetic mechanism is proposed.

Action Potentials↗
PubMed1993

Choreo-acanthocytosis like phenotype without acanthocytes: clinicopathological case report. A contribution to the knowledge of the functional pathology of the caudate nucleus.

Detailed clinical and neuropathological findings in two unrelated patients with a chorea-acanthocytosis-like phenotype (CA) are reported. One case met all the diagnostic criteria of CA and had a deceased brother with the same disease. The second case had a virtually identical phenotype to the former but without acanthocytes. These findings suggest that both patients are affected by the same disease and that acanthocytes are not essential to the diagnosis. Neuropathological autopsy studies on the brain of the second case showed selective atrophy of the caudate nucleus that seemed to correspond to the movement disorder and behavioural abnormalities prominent in this patient. In both subjects, morphometric and ultrastructural examination of the peripheral nerve showed loss of myelinated fibres, more accentuated distally, and cytoskeletal changes in the axoplasm. These findings support the hypothesis that peripheral neuropathy in CA is caused by distal axonopathy.

Acanthocytes↗
PubMed1993

Interleukin-6 levels in the cerebrospinal fluid and serum of patients with Guillain-Barré syndrome and chronic inflammatory demyelinating polyradiculoneuropathy.

Clinical and experimental findings suggest that humoral factors, such as anti-peripheral nerve antibodies and cytokines, may be implicated in the immunopathogenesis of Guillain-Barré syndrome (GBS) and chronic inflammatory demyelinating polyradiculoneuropathy (CIDP). Interleukin-6 (IL-6) is a multifunctional cytokine that promotes immunoglobulin synthesis by B lymphocytes. Increased IL-6 release is associated with autoantibody production in a number of immune-mediated and neoplastic disorders. To investigate the possible involvement of abnormal IL-6 release in inflammatory polyneuropathies, we assayed IL-6 levels in the cerebrospinal fluid (CSF) and serum of 23 patients with acute GBS and seven with CIDP. We also studied 69 patients with other non-inflammatory neurological diseases (NIND), 25 with other inflammatory neurological diseases (IND), four with brain tumors (BT), and 15 normal donors (serum alone) as controls. We found detectable levels of IL-6 in the CSF of 57% of GBS, 43% of CIDP, 60% of IND, 75% of BT, and 4% of NIND. In GBS patients, no correlation was found between CSF IL-6 values and other laboratory or clinical parameters, such as CSF total protein, CSF albumin, CSF IgG, CSF/serum albumin ratio, functional disability score, and time elapsed from disease onset. Serum IL-6 levels were increased in six of 23 (26%) GBS, in one of 39 (3%) NIND, and in one of seven (14%) IND, but in none of the CIDP or BT patients. There was no correlation between serum and CSF IL-6 values, but cytokine levels in GBS sera correlated with time elapsed from clinical onset.(ABSTRACT TRUNCATED AT 250 WORDS)

Acute Disease↗