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Biomedical subjects

I L Simone

Publications and source records attributed to I L Simone.

33 records · Page 2Linked to original sources

Serum and CSF anti-GM1 antibodies in patients with Guillain-Barré syndrome and chronic inflammatory demyelinating polyneuropathy.

High titers of antibodies directed against gangliosides, especially GM1, are found in the serum of patients with a variety of polyneuropathies, including those of the inflammatory type. We assayed anti-GM1 IgG and IgM levels in the serum and cerebrospinal fluid (CSF) of 23 patients with Guillain-Barré syndrome (GBS) and 10 with chronic inflammatory demyelinating polyneuropathy (CIDP) to investigate whether this immune response may also be localized within the intrathecal compartment and correlate with clinical parameters such as time interval since disease onset, disability score, preceding infectious episodes, and GM1 therapy. When compared to the control group, anti-GM1 IgG was increased in the serum of 39% of GBS and 10% of CIDP patients, whereas anti-GM1 IgM was elevated in 17% of GBS and none of the CIDP patients. In both patient groups, however, anti-GM1 antibody levels were more frequently elevated in CSF than paired sera: they belonged to the IgG class in 48% of GBS and 50% of CIDP patients, and to the IgM class in 48% of GBS and 55% of CIDP patients. In the GBS group, anti-GM1 IgM serum levels inversely correlated with time elapsed between sample collection and onset of disease (P < 0.05), whereas serum anti-GM1 IgG levels positively correlated with the loss of functional ability (P < 0.005). Increased anti-GM1 antibodies in GBS serum were not associated with clinical or serological evidence of infectious antecedents nor with previous GM1 treatment.(ABSTRACT TRUNCATED AT 250 WORDS)

Antibodies↗

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↗

Multiple sclerosis in childhood. Longitudinal study in 14 cases.

The Authors review the literature on the occurrence of multiple sclerosis in children and add 14 personal cases below the age of 15.5 years, the youngest being 6.4 years old. Modality of onset, clinical course, clinical classification according to the criteria proposed by McDonald and Halliday, paraclinical evidence of lesions and disability grade at the last control are widely discussed. Eleven cases were scheduled as clinically definite multiple sclerosis. In the youngest children the recovery may be often complete or the disability grade may be low.

Adolescent↗

Blood-cerebrospinal fluid barrier permeability to serum IgG subfractions and measurement of intrathecal IgG synthesis.

CSF/serum gradients of IgG subfractions separated by isoelectric focusing (IF) have been measured by high resolving laser densitometry. In patients with normal blood-CSF barrier permeability (N.25) and with barrier damage due to acute idiopathic polyneuropathy (N.15) and to medullary compression (N.17), the CSF/serum gradients of IgG subfractions were negatively correlated with their pI. This electrostatic selectivity appeared to be reverted in barrier damage due to acute meningoencephalitis (N.15). In a series of multiple sclerosis patients (N.31), the CSF/serum gradients of IgG subfractions lacking CSF oligoclonal bands have been used to assess the overall barrier permeability to serum IgG. All intra-BCB synthesized IgG subfractions could be measured by densitometry, whereas with other quantitative formulae, 23-26% of the results were false negatives; the total intrathecal IgG amount ranged from 0.01 to 11 mg/dl. The most frequent and prominent fractions appeared to be cathodic. Electrostatic and steric barrier selectivity must be taken into account when the amount of intrathecal IgG synthesis has to be measured.

Adolescent↗

Acute changes in blood-CSF barrier permselectivity to serum proteins after intrathecal methotrexate and CNS irradiation.

Ten children affected by acute lymphoblastic leukaemia without CNS involvement were treated with a CNS prophylaxis protocol. Intrathecal methotrexate and CNS irradiation (60Co) administered at different times both induced an increase in blood-CSF barrier permeability to serum proteins (albumin, IgG, alpha 2 macroglobulin). The relationship between permeability coefficients of proteins was analysed by theoretical porous or vesicular blood-CSF barrier models. The analysis indicated that both therapeutic procedures affect endothelial pinocytosis. An increase in radius of pinocytotic vesicles from 400 to 1500 A seemed the most relevant change. The damage of endothelial barrier permselectivity could be involved in acute and late delayed toxic effects of intrathecal methotrexate and of CNS irradiation.

Acute Disease↗

Heterogeneous models for blood-cerebrospinal fluid barrier permeability to serum proteins in normal and abnormal cerebrospinal fluid/serum protein concentration gradients.

Cerebrospinal fluid (CSF)/serum concentration gradients (Q) of individual proteins (albumin, IgG, alpha 2-macroglobulin) have been studied in controls and in patients in whom the lumbar CSF flow is altered (medullary compression) or the blood-CSF barrier (BCB) function impaired (acute idiopathic polyneuropathy and acute meningoencephalitis). The analysis of relationships among protein Q has been performed by total and multiple regressions and the actual BCB permeability to individual proteins has been interpreted according to the accepted theoretical porous or vesicular BCB models. The exponential Q-IgG vs. Q-albumin total regression, and the poor Q-alpha 2-macroglobulin vs. Q-albumin regression found in controls, together with the different multiple regressions among proteins and the high Q-IgG vs. Q-albumin partial regression coefficients found in medullary compression, acute idiopathic polyneuropathy and acute meningoencephalitis, indicated that different permeability mechanisms can be postulated. Heterogeneous, fairly independent permeability BCB mechanisms maintain the normal CSF/serum protein concentration gradient. Pinocytotic vesicles or pores of radius exceeding 1000-1500 A, probably located at the capillary endothelium, account for the main serum-derived CSF protein fraction(s) with large hydrodynamic radius (R). A more selective endothelial vesicular transport with a radius of 250 A transfers a negligible amount of protein from serum into CSF. Proteins with small R also enter the CSF through a set of selective pores of radius 120 A, probably at the level of the choroidal epithelium. Pinocytotic vesicles with a radius of 250 A and increased rate of formation induce the accumulation of proteins below an obstruction of lumbar CSF flow. An increased formation rate of vesicles with a radius of 450 A can explain the increased capillary permeability in nerve roots in acute idiopathic polyneuropathy. Loss of selectivity was the main feature of BCB in acute meningoencephalitis, and it seemed to be due to pores or vesicles with a radius larger than 1000-1500 A. The heterogeneity of BCB mechanisms must be taken into account when the intrathecal synthesis of a protein, also derived from serum (for example IgG), has to be measured.

Blood Proteins↗

Intrathecal IgG synthesis in multiple sclerosis: comparison between isoelectric focusing and quantitative estimation of cerebrospinal fluid IgG.

Isoelectric focusing of CSF and serum IgG followed by crossed immuno isoelectric focusing and direct immunofixation as well as quantitative assay of IgG and albumin were performed in 64 clinically definite multiple sclerosis patients. Intrathecal IgG synthesis was calculated according to the CSF IgG index and de novo CNS IgGsyn. Isoelectric focusing showed abnormal IgG fractions i CSF indicating increased intrathecal synthesis of oligoclonal IgG in 99% of patients. Only 62% and 70% of multiple sclerosis patients showed values of CSF IgG indices and de novo CNS IgGsyn higher than in controls. Increased intrathecal IgG synthesis was indicated more frequently by de novo CNS IgGsyn in patients with a normal CSF IgG index than by the CSF IgG index in patients with normal de novo CNS IgGsyn. All patients with blood CSF barrier damage had increased de novo CNS IgGsyn, but only 40% had an increased CSF IgG index. Isoelectric focusing seemed to be a more sensitive method to detect an increased intrathecal oligoclonal IgG synthesis than quantitative methods. Identification of abnormal IgG fractions can be performed easily and with more reproducible results by direct immunofixation than by crossed immuno isoelectric focusing. The formula for de novo CNS IgGsyn seemed more sensitive and less influenced by blood-CSF barrier damage than the CSF IgG index to detect increased intrathecal IgG synthesis in multiple sclerosis patients. No correlation was found between the CSF IgG pattern or amounts and age, duration, clinical course or therapy of the disease.

Cross Reactions↗

Isoelectric focusing and quantitative estimation of cerebrospinal fluid and serum IgG in idiopathic polyneuropathy.

Isoelectric focusing and quantitative estimation of serum and CSF IgG were performed in 85 patients with idiopathic polyneuropathy (IP), subdivided according to the clinical course (acute, subacute, recurrent, chronic). Acute IP very frequently had an increase of oligoclonal and/or polyclonal serum IgG during the progressive phase and blood-CSF barrier damage accompanied by polyclonal IgG intrathecal synthesis during the stationary phase. Polyclonal IgG intrathecal synthesis was also present in several not acute IP and seemed to forecast unfavorable course. Oligoclonal IgG synthesis occurs very rarely within CSF but is a frequent finding in serum of patients with IP. Abnormalities of the IgG serum pattern are neither specific for any clinical course of IP nor of prognostic value. The possible significance of such findings is discussed.

Adolescent↗

A case of Landau-Kleffner syndrome secondary to inflammatory demyelinating disease.

A 6-year old girl developed acquired aphasia with epilepsy and a paroxysmal EEG (Landau-Kleffner syndrome). Isoelectric CSF focusing showed oligoclonal IgG bands. Small lesions were visualized in periventricular left frontal white matter and right parietal lobe centrum semiovale with magnetic resonance imaging (MRI). After a week of ACTH therapy, the EEG paroxysmal activity disappeared; during the next few months, the language disorder improved. Further MRI examination showed a decrease in size and signal of the left frontal lesions, with localized white matter atrophy, dilatation of the subarachnoidal spaces, and disappearance of the right parietal lesion. The clinical and neuroradiologic features and the laboratory data suggest an acute disseminated encephalomyelitis.

Adrenocorticotropic Hormone↗

[Intrathecal synthesis of IgG in HIV infections].

CSF and serum of 80 HIV-seropositive patients in various stages of the disease were examined. Total as well as intrathecal IgG synthesis appeared to be frequently elevated in each diagnostic group. Abnormal CSF oligoclonal IgG fractions were significantly more frequent in asymptomatic patients. CSF pleocytosis was found with a lower percentage in neurological AIDS patients. In patients subdivided according to blood T helper cell count, the distribution of the abnormal CSF parameters confirms that the immunological response in the CNS is mediated by interaction with systemic immunity.

Adult↗

[Plasmapheresis in neuromuscular diseases. Personal cases].

The authors used plasmapheresis to treat 8 patients with myasthenia gravis and 26 with polyradiculoneuropathy. In myasthenia the treatment was effective in 85% of the cases, as reported in other studies. Good results occurred in some 80% of the cases with acute and relapsing polyradiculoneuropathy. In all cases plasma-exchange was started in the early stage. In chronic polyradiculoneuropathy the treatment was less effective. The authors discuss the advantages, disadvantages and prospects of this kind of therapy.

Acute Disease↗

Cerebrospinal fluid (CSF) parameters and clinical course of multiple sclerosis.

The separate correlations among CSF and clinical parameters (mononuclear cell count, assay of intrathecal IgG synthesis, assessment of blood-brain barrier permselectivity to albumin and alpha 2-macroglobulin, detection of oligoclonal intrathecal IgG isoelectric spectro-type; age, disease duration, disability, number of bouts) were investigated by multiple linear regression in 100 multiple sclerosis patients subdivided according to the course and the phase of the disease. Results indicate that the complexity of the oligoclonal CSF IgG isoelectric spectrotype increases, but the overall amount of intrathecal IgG synthesis decreases with increasing number of bouts or disease duration in relapsing remitting and in progressive courses respectively. The CSF mononuclear pleocytosis was low in progressive forms, and it appeared to be linked to the intrathecal IgG synthesis changes. The IgG synthesis rate was proportional to CSF pleocytosis, but a negative correlation between pleocytosis and complexity of CSF IgG spectrotype was found. About 40% of patients had a blood-brain barrier damage. The increased permeability to albumin was related to the number of previous bouts, whereas the CSF pleocytosis seemed to be accompanied by a loss of barrier selectivity to large serum molecules. High CSF IgG index, high mononuclear cell count and low number of prominent oligoclonal CSF IgG fractions characterize the less active or short-lasting disease. Low CSF IgG index with numerous, faint, abnormal IgG CSF bands, low mononuclear cell number and increased barrier permeability to albumin are associated with long-lasting or steady progressive disease.

Adult↗