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C Fieschi

Publications and source records attributed to C Fieschi.

At least 19 recordsLinked to original sources
PubMed2002

Inherited disorders of IL-12- and IFNgamma-mediated immunity: a molecular genetics update.

In the last 6 years, considerable advances have been made in the molecular analysis of a rare clinical syndrome: Mendelian susceptibility to mycobacterial disease (MSMD). Infection with poorly virulent environmental non-tuberculous mycobacteria (NTM) or vaccination with bacillus Calmette-Guerin (BCG) may cause disseminating and even fatal disease in individuals suffering from this syndrome. Mutations in five genes (IFNGR1, IFNGR2, STAT1, IL12B and IL12RB1) have been shown to be responsible for MSMD and further allelic heterogeneity accounts for the existence of nine distinct inherited disorders. All of these disorders are caused by impaired IFNgamma-mediated immunity. These results have important medical and biological implications. In this report, we update the disease-causing mutations reported in the literature.

Adult↗
PubMed2001

Impairment of mycobacterial but not viral immunity by a germline human STAT1 mutation.

Interferons (IFN) alpha/beta and gamma induce the formation of two transcriptional activators: gamma-activating factor (GAF) and interferon-stimulated gamma factor 3 (ISGF3). We report a natural heterozygous germline STAT1 mutation associated with susceptibility to mycobacterial but not viral disease. This mutation causes a loss of GAF and ISGF3 activation but is dominant for one cellular phenotype and recessive for the other. It impairs the nuclear accumulation of GAF but not of ISGF3 in heterozygous cells stimulated by IFNs. Thus, the antimycobacterial, but not the antiviral, effects of human IFNs are principally mediated by GAF.

Adult↗
PubMed2001

Migraine and arterial dissection in a young woman.

Ischemic stroke in young adults is rare (5%-10% of all ischemic strokes) and, in absence of other risk factors, may be associated with migraine. We describe the case of a 34-year-old woman, with a history of migraine without aura, who presented a sudden onset of headache with Horner's syndrome, and in whom neuroimaging showed evidence compatible with fibromuscular dysplasia (FMD) and arterial dissection of the extracranial internal carotid artery (ICA) and the carotid siphon. In our opinion, in young women with a long history of migraine, a careful study of the extracranial and intracranial arteries would be useful, although the cost/benefit ratio does not at present justify such a procedure. Our aim in the future is, therefore, to study a larger sample of migraine patients in order to find those patients who are most at risk of arterial dissection and who should, consequently, be carefully studied.

Adult↗
PubMed2001

Treatment of cerebrovascular diseases: state of the art and perspectives.

Ischaemic penumbra is defined as the area of brain tissue that maintains some blood flow following ischaemic accident. This zone may be rescued by both neuroprotection and arterial revascularization. Early thrombolysis has been used with encouraging results since 1995 in several trials testing both streptokinase and recombinant tissue plasminogen activator (r-TPA): the r-TPA results are definitely more positive than those of streptokinase, despite an increased incidence of symptomatic haemorrhagic transformation, r-TPA significantly reducing death or dependency at the end of follow-up. Despite the fact that some experimental periods of application of these therapeutic strategies demonstrated real cost-effective benefits, only 1% of patients reaching hospital in time for thrombolysis are currently treated. This is because the profile of patients at risk of haemorrhagic transformation, which is definitely the most feared side-effect of thrombolysis in stroke, is yet to be clearly defined. Extended computerized tomography (CT) signs of the index stroke have been repeatedly indicated as reliable predictors of haemorrhagic transformation even if currently there are significant discrepancies in the criteria adopted by different researchers to define early CT signs. Based on experimental ischaemia, strategies for protecting the basal lamina during thrombolysis are suggested: neuroprotection is the second approach to stroke therapy; pharmacological reperfusion and brain protection are probably mutually dependent.

Cerebrovascular Disorders↗
PubMed2001

Keynote address.

"Acute strokes are here to stay": this could be the sad conclusion after decades of stroke research. Generalized prevention of ischemic stroke is not fully successful. After the decline in stroke incidence observed by 1970, partly related to better management of vascular risk factors, there has again been an increase in stroke frequency all around the world. This phenomenon may be explained by the lack of educational modalities for modification of lifestyle behavior, the small impact of high-risk individual prevention strategy, and the lack of rationale and guidelines for multiple approaches. In the meantime, the benefits of acute intensive management of stroke have been demonstrated. There is now considerable evidence that careful monitoring and management of general and cerebral functions in a dedicated stroke unit or by a specialized stroke team are superior to management in a neurologic or general ward. Currently, one way of optimizing limited personnel resources is to connect the stroke unit of a main hospital with peripheral hospitals via a computer network. Experts in the central stroke unit can then make on-line evaluations of CT and ultrasound examinations performed in the local hospital and recommend the best course of patient management. This new approach of treating stroke as an emergency will also require educational programs directed at the general public, general practitioners, and primary and emergency department physicians, to teach the recognition of stroke symptoms and the importance of treating stroke with the same urgency as for myocardial infarction (MI).

Brain Ischemia↗
PubMed2001

High levels of interferon gamma in the plasma of children with complete interferon gamma receptor deficiency.

We have found that children with complete interferon gamma (IFNgamma) receptor deficiency, unlike patients with other genetic defects predisposing them to mycobacterial diseases, have very high levels of IFNgamma in their plasma. This unexpected observation provides a simple and accurate diagnostic method for complete IFNgamma receptor deficiency in children with clinical disease caused by bacille Calmette-Guérin vaccines or environmental nontuberculous mycobacteria.

BCG Vaccine↗
PubMed2000

Impairment of STAT activation by IL-12 in a patient with atypical mycobacterial and staphylococcal infections.

IL-12 plays a pivotal role in the stimulation of immune responses against intracellular infections. This role is manifested in the increased susceptibility to atypical mycobacterial and salmonella infections among individuals whose lymphocytes lack expression of IL-12Rbeta1. Here, we report on a patient with Mycobacterium avium infection, recurrent Staphylococcus aureus sinusitis, and multiple adverse drug reactions whose T cells were unable to produce IFN-gamma or proliferate in response to IL-12 despite the expression of wild-type IL-12Rbeta1 and IL-12Rbeta2. The defect in these functional responses to IL-12 was selective, as cytolytic activity induced by IL-12 was intact, and lymphocytes were responsive to stimulation by IL-2. An examination of cytokine signaling revealed that STAT4 and extracellular regulated kinase 1 (ERK1) activation by IL-12 was intact, whereas the activation of STAT1, -3, and -5 by IL-12 was lost. This impairment of STAT activation was specific for IL-12, as STAT activation by IL-2, IL-15, and IFN-gamma was unaffected. These findings demonstrate that the activation of STAT4 alone is not sufficient for IL-12-induced IFN-gamma production and proliferation and suggest that other STATs play a role in these responses to IL-12. While the etiology of the impaired IL-12 signaling in this patient has not yet been elucidated, the absence of mutations in IL-12Rbeta1 or IL-12Rbeta2 and the preservation of STAT4 activation raise the possibility that there may be a mutation in an as yet undiscovered component of the IL-12 signaling complex that is normally required for the recruitment and activation of STAT1, -3, and -5.

Child, Preschool↗
PubMed2000

A novel missense mutation (C30S) in the gene encoding tumor necrosis factor receptor 1 linked to autosomal-dominant recurrent fever with localized myositis in a French family.

OBJECTIVE: To characterize both phenotypic (clinical features and magnetic resonance imaging [MRI] findings) and genotypic aspects of autosomal-dominant recurrent fever, also known as tumor necrosis factor receptor (TNFR)-associated periodic syndrome (TRAPS), in a French family and to investigate the role of the mutated 55-kd tumor necrosis factor alpha (TNFalpha) receptor (TNFR1) in the pathogenesis of the disease. METHODS: The coding region of TNFR1 was sequenced in 2 individuals with TRAPS (the propositus and her grandfather) and in 3 clinically unaffected relatives. Expression of soluble TNFR1 (sTNFR1) was investigated in 3 of the family members carrying a C30S mutation in TNFR1, and was compared with the levels of soluble TNFR2 (sTNFR2) by enzyme-linked immunosorbent assay. The membrane TNFR1 expression was then compared with membrane TNFR2 levels at the surface of peripheral blood mononuclear cells by flow cytometric analysis. The clinical heterogeneity in this French family was investigated by searching polymorphic variants in the TNFalpha promoter by DNA sequencing. RESULTS: Both the disease course and the clinical presentation in the propositus were highly indicative of TRAPS. MRI study of the segmental inflammatory process in the limbs showed abnormal signals in the muscle and subcutaneous tissue without involvement of adjacent joints or fascia. A novel missense mutation, C30S, in the first extracellular N-terminal cysteine-rich domain (CRD1) of TNFR1 was characterized in the propositus, her affected grandfather, and her clinically unaffected father. Expression of membrane TNFR1 at the surface of monocytes and polymorphonuclear leukocytes, as well as the levels of sTNFR1 in serum when the disease was not active were not modified in the 3 individuals carrying the TNFR1 C30S mutation. In contrast, during attacks, sTNFR1 levels remained abnormally low, as compared with the levels in unrelated patients with active adult-onset systemic Still's disease. The clinical heterogeneity could not be explained by a polymorphic variant in the TNFalpha promoter. CONCLUSION: TRAPS is a distinct clinical and radiologic disease entity that is responsible for recurrent fever and migratory cellulitis-like processes with localized myositis. We have identified a novel TNFR1 mutation, C30S, that is located in the CRD1 domain in a French family affected by the disease. This mutation seems to affect the level of sTNFR1, which did not increase in the propositus during inflammatory attacks.

Adolescent↗
PubMed2000

Human interferon-gamma-mediated immunity is a genetically controlled continuous trait that determines the outcome of mycobacterial invasion.

Individuals with inherited disorders of interferon gamma (IFN-gamma)-mediated immunity appear to be specifically vulnerable to mycobacterial infections. The severity of clinical features of affected individuals differs between cases. Some patients die of mycobacterial infection in early childhood, whereas others have long asymptomatic periods in childhood and as adults. This rare syndrome also shows high allelic and non-allelic genetic heterogeneity. Mutations in IL12B, encoding the interleukin (IL)-12 p40 subunit, and in IL12RB1, encoding the beta1 chain of the IL-12 receptor, result in impaired IFN-gamma production. Mutations in IFNGR1 and IFNGR2, encoding the two IFN-gamma receptor chains, and mutations in STAT1, encoding an essential signaling component, result in impaired cellular responses to IFN gamma. Different types of mutation define two types of complete and two types of partial IFNgammaR1 deficiency. Complete and partial IFNgammaR2 deficiency have also been described. We herein compare the genotypes, cellular phenotypes, and clinical phenotypes of healthy individuals and patients with the seven known genetic disorders impairing cellular responses to IFN-gamma. Patients with defective IFN-gamma production were not considered in this study. The mutations and clinical features of patients with IFNgammaR1, IFNgammaR2, and STAT-1 deficiency are reviewed. Selected cell lines from each of the eight groups were tested for their response to IFN-gamma. We find that individuals may be classified into four broad groups based on genotype, cellular phenotype, and clinical phenotype (normal individuals and patients with mild, intermediate, or severe disease). This correlation suggests that IFN-gamma-mediated cell activation is a genetically controlled quantitative trait and that it determines the outcome of mycobacterial invasion in man.

Adult↗
PubMed2000

Morphological and functional characteristics of patent foramen ovale and their embolic implications.

BACKGROUND AND PURPOSE: Transesophageal echocardiography (TEE) has detected a high prevalence of patent foramen ovale (PFO) in stroke patients, but the clinical implications of the distinctive characteristics of this patency are still a matter of debate. METHODS: We studied 350 patients with acute ischemic stroke or transient ischemic attack (TIA) within 1 week of admission. Of these, 101 (29%) were identified by contrast TEE to have a PFO; 86 patients (25%) were cryptogenic stroke patients, and 163 were excluded because of the presence of a definite or possible arterial or clinical evidence of a source of emboli or small-vessel disease. Thirteen PFO subjects without a history of embolism were designated as the control group. All PFO and cryptogenic stroke patients were followed up by neurological visits. RESULTS: Compared with controls, PFO patients with acute stroke or TIA more frequently presented with a right-to-left shunt at rest and a higher membrane mobility (P:<0. 05). Patients with these characteristics were considered to be at high risk. During a median follow-up period of 31 months (range, 4 to 58 months), 8 PFO and 18 cryptogenic stroke patients experienced recurrent cerebrovascular events. The cumulative estimate of risk of cerebrovascular event recurrence at 3 years was 4.3% (95% confidence interval [CI], 0% to 10.2%) for "low-risk" PFO patients, 12.5% (95% CI, 0% to 26.1%) for "high-risk" PFO patients, and 16.3% (95% CI, 7. 2% to 25.4%) for cryptogenic stroke patients (high-risk PFO versus low-risk PFO, P:=0.05). CONCLUSIONS: The association of right-to-left shunting at rest and high membrane mobility, as detected by contrast TEE, seems to identify PFO patients with cerebrovascular ischemic events who are at higher risk for recurrent brain embolism.

Aorta↗
PubMed2000

In a novel form of IFN-gamma receptor 1 deficiency, cell surface receptors fail to bind IFN-gamma.

Complete IFN-gamma receptor ligand-binding chain (IFNgammaR1) deficiency is a life-threatening autosomal recessive immune disorder. Affected children invariably die of mycobacterial infection, unless bone marrow transplantation is undertaken. Pathogenic IFNGR1 mutations identified to date include nonsense and splice mutations and frameshift deletions and insertions. All result in a premature stop codon upstream from the segment encoding the transmembrane domain, precluding cell surface expression of the receptors. We report herein two sporadic and two familial cases of a novel form of complete IFNgammaR1 deficiency in which normal numbers of receptors are detected at the cell surface. Two in-frame deletions and two missense IFNGR1 mutations were identified in the segment encoding the extracellular ligand-binding domain of the receptor. Eight independent IFNgammaR1-specific mAb's, including seven blocking antibodies, gave recognition patterns that differed between patients, suggesting that different epitopes were altered by the mutations. No specific binding of (125)I-IFN-gamma to cells was observed in any patient, however, and the cells failed to respond to IFN-gamma. The mutations therefore cause complete IFNgammaR1 deficiency by disrupting the IFN-gamma-binding site without affecting surface expression. The detection of surface IFNgammaR1 molecules by specific antibodies, including blocking antibodies, does not exclude a diagnosis of complete IFNgammaR1 deficiency.

Adolescent↗
PubMed2000

MRI of spinal cord in MS.

Over the last 10 - 15 years, magnetic resonance imaging techniques have had a major impact in understanding and managing multiple sclerosis. The present review briefly summarises the current usefulness of spinal cord MRI in MS disease, examining the frequency, distribution and main characteristics of spine MS plaques; the differential diagnosis with other spinal cord disease was also described. Finally we considered how newer imaging sequences when added to semi-automated quantitative methods, may give us a putative tool to reliably quantify subtle changes which develop on the spinal cord of MS patients over time.

Diagnosis, Differential↗
PubMed1999

Cerebrospinal fluid isoprostane shows oxidative stress in patients with multiple sclerosis.

The CSF level of the isoprostane 8-epi-prostaglandin (PG)-F2alpha (a reliable marker of oxidative stress in vivo) was three times higher in subjects with definite MS than in a benchmark group of subjects with other neurologic diseases. This increase was not correlated with that of PGE2 levels, measured as an index of cyclooxygenase activity, and was much lower in steroid-treated patients. The levels of 8-epi-PGF2alpha were moderately correlated with the degree of disability.

Adult↗
PubMed1999

Further study on the specificity and incidence of neutralizing antibodies to interferon (IFN) in relapsing remitting multiple sclerosis patients treated with IFN beta-1a or IFN beta-1b.

The development of neutralizing antibodies (NAbs) to interferon (IFN) is a common phenomenon of IFN beta therapy for relapsing-remitting multiple sclerosis (RRMS) patients. Here we examine the specificity of NAbs developed during therapy for RRMS with recombinant interferon (rIFN) beta-1a or rIFN beta-1b, and study the effect of switching from rIFN beta-1a to rIFN beta-1b on the incidence and specificity of NAbs. The relative ability to neutralize rIFN beta-1a and beta-1b was assayed in sera positive for NAbs derived from RRMS patients treated with either rIFN beta-1a (N=9) or rIFN beta-1b (N=16), while the incidence and specificity of NAbs to IFN beta developed during therapy were studied in 50 RRMS patients who were treated for two years with rIFN beta-1a followed by a further year either switching to rIFN beta-1b (N=34) or continuing treatment with rIFN beta-1a (N=16). The results show that all positive sera, independent of the source, may recognize both forms of rIFN beta and that a further year of treatment does not significantly affect the incidence and specificity of the NAbs developed during the first two years of treatment even if treatment is switched to a different type of IFN beta. The data then suggests that it is unlikely that the administration of rIFN beta-1b to anti-rIFN beta-1a NAbs-positive patients can overcome the inhibitory effect exerted by the serum antibodies (and vice versa), and that a further period of treatment with IFN beta-1b in patients previously treated with rIFN beta-1a does not significantly change the pattern of antibody response to IFN beta.

Adjuvants, Immunologic↗
PubMed1999

Excessive daytime sleepiness in myotonic dystrophy.

The aim of the present study was to assess whether or not there is any correlation between magnetic resonance imaging (MRI) abnormalities and excessive daytime sleepiness (EDS) in a consecutive series of patients with myotonic dystrophy (MD). The influences of nocturnal breathing abnormalities and sleep morphology on EDS were also evaluated. Ten MD patients were studied by means of an all-night polysomnographic recording, the multiple sleep latency test (MSLT) and MRI. Diagnosis of MD was established on the basis of the clinical and electrophysiological evidence of myotonia as well as of the characteristic genetic pattern. No patient had respiratory failure. Polysomnography and MSLT were also evaluated in ten healthy age-matched controls under the same environmental conditions. The mean MSLT value was significantly lower in patients than in controls. Five of the ten patients were found to have pathological EDS. The quantitative sleep variables and the nocturnal apnoeas in these five patients were not significantly different from those of the patients without EDS. As two patients did not undergo MRI because of claustrophobia, the MRI data were considered in eight patients. Corpus callosum (CC) atrophy was detected in four patients, whereas three patients showed hyperintense areas in the white matter. No correlation was found between EDS and MRI indexes of subcortical atrophy as well as volume of the hyperintense areas. By contrast, a correlation was found between the MSLT value and the reduction in the anterior area of the CC. Our data suggest that CC atrophy might occur in MD patients, and that the size of the CC anterior area might be associated with EDS.

Adult↗
PubMed1999

Assessment of brain tissue viability under clinical circumstances.

The growing body of clinical and instrumental information that can be gathered from the earliest phases of stroke has radically modified the way in which neurologists tackle the treatment of stroke patients. It is now theoretically possible to tailor therapeutic choices on the basis of prognostic estimates made within a few hours of stroke onset, that is at a time when numerous options to limit the ischemic insult are still open. However, once many hours or even days have passed, all one can do is witness the effects of a natural course which by then is virtually unmodifiable. This applies not only to stroke patients being treated within the context of pharmacological trials, but also to those in daily clinical management, since some choices, such as when and how to treat brain oedema and give thrombolytics, may now be made earlier and more accurately than in the past. Emergency CT in particular discloses important indices of subsequent clinical evolution and outcome, thus adding to already well-known predictors such as age and severity of neurological status at hospital admission [20]. CT does have the aforementioned limitations regarding inter-observer agreement, which may, however, be minimised by an appropriate training of observers. Moreover it has intrinsic limitations regarding the visualisation of the actual brain tissue damage, since up to one fifth of patients with no or very limited early CT signs may present symptomatic hemorrhagic transformation after thrombolysis [23] and approximately one sixth of early deteriorating patients do not show early CT signs [52]. Other techniques, such as positron and single photon emission tomography and in particular MR imaging, which may shed light on tissue viability and perfusion as well as arterial patency simultaneously, might be able to provide more accurate information [19] Nevertheless, CT is still the most widely used tool in clinical centres which hospitalise stroke patients, and is unlikely to be routinely replaced by the other imaging devices in the foreseeable future. Consequently, there is an urgent need both for a general consensus on the identification criteria of early CT signs and for the widest possible awareness of knowledge regarding CT capabilities among neurologists [47], waiting for the wide applicability of newer technologies.

Brain↗