PubMed Health⌕ Search

Biomedical subjects

L Volpi

Publications and source records attributed to L Volpi.

At least 19 recordsLinked to original sources
PubMed2004

Rhythmic teeth grinding induced by temporal lobe seizures.

The authors report the clinical and polygraphic features of rhythmic teeth grinding observed in a patient as the predominant symptom related to temporal lobe seizures during sleep and wakefulness. This observation demonstrates that exceptionally a teeth-grinding event can be not only a parasomnia (sleep bruxism) but also an epileptic-related motor event. Electromyographic and autonomic features of seizure-related teeth grinding support the interpretation of this motor phenomenon as a particular form of masticatory activity.

Adult↗
PubMed2004

Clinical features and long term outcome of epilepsy in periventricular nodular heterotopia. Simple compared with plus forms.

OBJECTIVES: Little is known about the long term outcome of patients with periventricular nodular heterotopia (PNH) and epilepsy, particularly the course of seizures. This study investigated the electroclinical and prognostic features of 16 patients with PNH. METHODS: Of 120 patients with epilepsy and malformations of cortical development, 16 had PNH. Of these, eight patients had periventricular nodules only (simple PNH) and eight also presented with other cortical or cerebral malformations (subcortical heterotopia; polymicrogyria; focal dysplasia; schizencephaly; cortical infolding; agenesis of the corpus callosum; mega cisterna magna and cerebellar atrophy) (PNH plus). All patients underwent clinical, neurophysiological, and MRI investigation. The mean follow up was 17.3 years (2-40 years). RESULTS: Two electroclinical patterns emerged: (1) The first pattern, associated with simple PNH, was characterised by normal intelligence and seizures, usually partial, which began during the second decade of life. The seizures never became frequent and tended to disappear or become very rare. The EEG showed focal abnormalities. (2) The second pattern, associated with PNH plus, was characterised by mental retardation and seizures that began during the first decade of life. The seizures were very frequent in most cases and sudden drops were observed in six patients. Seizures were medically refractory in four patients. The EEG showed focal and bisynchronous abnormalities. CONCLUSIONS: Two groups of PNH patients with different electroclinical and neuroradiological features can be identified after a long term follow up. The presence of other types of cortical or cerebral malformations, in addition to periventricular nodules, determines a poor prognosis.

Abnormalities, Multiple↗
PubMed2002

Mutation analysis of the BRCA1 gene in Malaysian breast cancer patients.

Thirty patients with early onset breast cancer or familial breast cancer from Malaysia were analysed for germline mutation in the early onset breast cancer I gene (BRCA1). Direct sequencing of the entire coding region of BRCA1 identified a frameshift mutation, c.5447-5448insC (insC5447) (codon 1776 of exon 21) in a patient aged 32 of the Malay ethnic origin, who had no family history of breast and/or ovarian cancer. Eight polymorphisms (2201C > T, 2430T > C, P871L, E1038G, K1183R, 4427T > C, S1613G and IVS8-57delT) were identified in the samples tested.

Adult↗
PubMed2000

Encephalopathy with electrical status epilepticus during slow sleep or ESES syndrome including the acquired aphasia.

Encephalopathy with electrical status epilepticus during sleep or ESES is an age-dependent and self-limited syndrome whose distinctive features include a characteristic age of onset (with a peak around 4-5 years), heterogeneous seizures types (mostly partial motor or unilateral seizures during sleep and absences or falls while awake), a typical EEG pattern (with continuous and diffuse paroxysms occupying at least 85% of slow wave sleep) and a variable neuropsychological regression consisting of IQ decrease, reduction of language (as in acquired aphasia or Landau-Kleffner syndrome), disturbance of behaviour (psychotic states) and motor impairment (in the form of ataxia, dyspraxia, dystonia or unilateral deficit). Despite the long-term favourable outcome of epilepsy and status epilepticus during sleep (SES), the prognosis is guarded because of the persistence of severe neuropsychological and/or motor deficits in approximately half of the patients. No specific treatment has been advocated for this syndrome, but valproate sodium, benzodiazepines and ACTH have been shown to control the seizures and the SES pattern in many cases, although often only temporarily. Subpial transection is proposed in some instances as in non-regressive acquired aphasia. Recent data support the concept that ESES syndrome may include a large subset of developmental or acquired regressive conditions of infancy.

Aphasia↗
PubMed1999

Stimulation of endogenous adenosine release by oral administration of quercetin and resveratrol in man.

Epidemiological evidence indicates that moderate alcohol consumption is associated with a significant decrease in the incidence of certain cardiovascular disorders, which can lead to impaired quality of life and to death. However, there are no objective data suggesting a cause-effect relationship and detailed research based on definitive working hypotheses is needed. We tested two flavonoids in man and found that these substances can belong, at least in part, to a wine-dependent mechanism, which leads to increased adenosine plasma levels. If these results could be confirmed by analyzing all the possible influences leading to blood nucleoside increase, a hypothesis of diet-dependent cellular preconditioning could be discussed.

Adenosine↗
PubMed1998

Chromosomal instability in fibroblasts and mesenchymal tumors from 2 sibs with Rothmund-Thomson syndrome.

Rothmund-Thomson syndrome (RTS) is a rare autosomal recessive genodermatosis associated with increased risk of mesenchymal tumors. The putative gene has been provisionally assigned to chromosome 8. Using a cytogenetic-molecular approach, we studied lymphocytes, fibroblasts, osteosarcoma (OS) and malignant fibrous histiocytoma (MFH) from 2 affected fraternal twins, looking for constitutive markers of chromosome instability and tumor chromosomal changes which might reflect the common genetic background. The rate of spontaneous chromosome aberrations was not increased in lymphocytes. Conversely, karyotyping of primary fibroblasts from one sib evidenced chromosome breaks and both numerical and structural chromosome changes in 24% and 17% of the metaphases respectively. FISH of a 8q21.3 cosmid allowed us to detect trisomy of the target region on 7% of fibroblast nuclei from both sibs, 47% and 12% of OS and MFH cells. Pronounced chromosomal instability and clonal rearrangements leading to different chromosome-8 derivatives were detected in both tumors. CGH experiments showed multiple gains/losses, among which del(6q), also revealed by cytogenetics, and 7p gain were common, whereas 8q amplification was present only in OS. Chromosomal instability, observed in fibroblasts from the RTS patients studied, accounts for the increased risk of mesenchymal tumors in these patients.

Adolescent↗
PubMed1997

A neurophysiological study in children and adolescents with Crigler-Najjar syndrome type I.

We studied the neurophysiological features of five patients (age range: 4-20 years) suffering from Crigler-Najjar syndrome type I (CNsI) by means of multimodal (brainstem, somatosensory, motor) evoked potentials and periodic EEG-polygraphic recordings (follow-up: 3 months-4.5 years). Two patients presented with neurological disturbances, consisting mainly of mental slowing, motor impairment and seizures. Both of them presented an abnormal EEG, characterized by slowing of background activity associated with paroxysmal discharges. Liver transplantation was performed in one of these two patients and was followed by improvement of both the neurological picture and EEG activity. In a third patient, clinically normal, after two years of follow-up, the EEG started to show paroxysmal activity during sleep or when evoked by intermittent photic stimulation. In these three patients, multimodal evoked potentials were unremarkable. The remaining two younger subjects did not show any clinical or EEG abnormality. Our findings suggest that, whereas in newborns and infants evoked potentials have been demonstrated as reliable techniques to monitor bilirubin neurotoxicity, in children and adolescents with CNsI, EEG seems to be more sensitive in evaluating patients for neurological damage and effectiveness of therapeutic strategies adopted.

Adolescent↗
PubMed1997

Localization of fos, jun, kit and SCF mRNA in human placenta throughout gestation using in situ RT-PCR.

The expression pattern of c-fos, c-jun, c-kit and stem cell factor (SCF) has been investigated in developing human placenta using the highly sensitive technique of in situ reverse transcriptase-polymerase chain reaction (RT-PCR). Specific transcripts of all genes under study were observed in first-trimester placenta sections. c-fos, c-jun, c-kit and SCF transcripts were localized in cells of the villous stroma; fos, jun and kit-specific mRNAs were also found in endothelial cells; fos, kit and SCF mRNAs were detected in villous trophoblast cells. In mid-trimester and term placenta specimens only SCF transcripts were observed, restricted to trophoblast cells. The lack of c-fos transcripts in placenta from the second and third trimesters is a finding that contrasts with data from the literature obtained using extractive techniques. Parallel immunocytochemistry of placenta specimens from the three pregnancy stages under study revealed the fos protein only in first-trimester placenta, in agreement with the in situ RT-PCR findings. We conclude that the in situ RT-PCR technique is most suitable for gene expression studies because of its high level of sensitivity in correctly assigning the signal to specific cell types in complex tissues.

DNA Primers↗
PubMed1996

An improved procedure for in situ RTPCR.

Direct in situ RTPCR has been successfully applied to paraffin-embedded human placental specimens. The expression of stem cell factor (SCF) mRNA visualized in cytotrophoblast and stromal cells is validated by the lack of any specific signal in parallel specimens where reverse transcription is omitted.

Base Sequence↗
PubMed1996

Microsatellite instability in IVS3 of murine c-fes gene: tumor-associated rearrangement and mammalian divergence.

The murine lymphomacrophage hybrids ESb, EbF1, EbF2-c4, which express c-fes constitutively, were found by Southern analysis to bear a c-fes deletion of almost 100 bp. The deleted allele was transmitted to the metastatic hybrids by their nonexpressing, poorly metastatic T-lymphoma progenitor Eb, which also has a structurally normal c-fes allele. PCR amplification and sequencing of fes cDNA spanning exons 3-5, where the deletion mapped, ruled out any involvement of coding sequences in the rearrangement. PCR amplification of the as yet unsequenced murine c-fes IVS3 and IVS4 showed they are about 50% longer than their human and feline homologs. Sequencing of IVS4 showed no difference between tumor and control DNA. Sequencing of part of the approximately 2600-bp IVS3 was guided by the restriction analysis of PCR products from control and hybrid DNAs. This showed that differences from the control appeared to be mainly located in the 900-bp HindIII-EcoRI fragment, localized in the middle of IVS3. As all three hybrids had the same restriction map, this fragment was sequenced in one of them (ESb). A run of >200 CA repeats was found in control DNA, and a reduction in the CAn microsatellite accounted for most of the c-fes deletion in the ESb hybrid. Interestingly, the 50% reduction in the size of human and feline c-fes IVS3 as compared with the murine homolog is mostly due to contraction of the same microsatellite.

Animals↗
PubMed1996

Isochromosome 15q of maternal origin in a Prader-Willi patient with pituitary adenoma.

We report on a Prader-Willi syndrome (PWS) patient carrier of a balanced 15q15q translocation and affected by a prolactin-secreting pituitary adenoma. Evidence provided by molecular studies indicates that the structural rearrangement is an isochromosome of maternal origin. According to the identification of isodisomy as the basis of the association of rare disorders and the recent report on chromosome 15 monosomy and nullisomy in pituitary adenoma, we suggest that in our case PWS and pituitary adenoma might be related.

Adenoma↗
PubMed1996

Electroclinical features of idiopathic generalised epilepsy with persisting absences in adult life.

OBJECTIVES: To describe the electroclinical features of typical absences persisting in adult life. METHODS: Twelve adult patients (aged 21 to 56 years) with idiopathic generalised epilepsy featuring typical absences as the prominent clinical feature were studied. All patients underwent a full clinical and neurophysiological investigation including ictal documentation of seizures. RESULTS: Neurological examination and neuroradiological investigations were normal in all cases. Clinical findings included a median age at onset of absences of 14 (range 4-32) years, almost constant tonic-clonic seizures (in 83% of patients), frequent episodes of absence status (in 33% of patients), and associated cognitive or psychiatric disturbances. Interictal EEG findings showed normal background activity, generalised paroxysms of spike waves or polyspike waves, and inconstant focal spikes (in five patients); runs of polyspikes were seen during non-REM sleep. Ictal EEG findings showed generalised spike waves at 3 Hz, sometimes preceded by multiple spikes, or more complex EEG patterns with sequences of polyspikes intermingled with spike waves or polyspike waves, showing discharge fragmentation or variation of intradischarge frequency. CONCLUSION: The results of the present study show that absences persisting in adult life may show particular clinical and EEG patterns, distinct from those in childhood or adolescence.

Adult↗
PubMed1995

Pharmacokinetics and pharmacodynamics of neutrophil-associated ciprofloxacin in humans.

OBJECTIVE: To study the possibility that the penetration of the antibiotic ciprofloxacin into polymorphonuclear leukocytes (PMN) may be associated with some changes in cell reactivity. DESIGN: Superoxide anion and chemiluminescence generation induced by formyl-methionyl-leucyl-phenylalanine (fMLP) and platelet-activating factor (PAF) were studied ex vivo in 12 healthy volunteers (mean age, 53.15 +/- 16.3 years; mean body weight, 71.23 +/- 6.9 kg) at fixed intervals up to 72 hours from the administration of a single oral dose of 250 mg ciprofloxacin. Cytosolic free calcium levels ([Ca2+]i) in resting and stimulated cells were also evaluated. The dynamic parameters of the effects on PMNs were compared with the kinetic profile of the drug in plasma and in PMNs. RESULTS: Superoxide generation induced by the stimulating agents increased significantly, reaching a peak after 12 hours (+116% [p < 0.001] for fMLP and +66% [p < 0.05] for PAF). Similarly, chemiluminescence production showed a threefold increase in the response to the stimulating agents 12 hours after drug administration (p < 0.001). The increase in [Ca2+]i in stimulated PMNs was significantly potentiated (p < 0.001). The mathematic analysis of the effects of ciprofloxacin showed that time to maximal activity was between 10.4 hours (PAF-dependent [Ca2+]i increase), and 15 hours (fMLP-induced superoxide anion and chemiluminescence production). The ratio of PMNs to plasma ciprofloxacin concentration increased progressively, from 0.5 at 30 minutes to 10.4 after 24 hours. In addition, time to maximal activity and half-life differed in PMNs and in plasma (4.66 versus 1.90 hours and 13.03 versus 7.28 hours, respectively). CONCLUSIONS: Ciprofloxacin administration induced a long-lasting enhancement of PMN reactivity to fMLP and PAF. The levels of the drug in the cells were greater and more sustained in the time than those in plasma.

Adult↗
PubMed1995

Increase in plasma levels of adenosine and adenine nucleotides after intravenous infusion of buflomedil in humans.

To clarify the mode of action of the vasoactive agent buflomedil, we evaluated plasma levels of adenosine and adenine nucleotides after intravenous (i.v.) infusion in humans of 50, 100, and 200 mg of the drug in 20 min. Buflomedil induced an increase of the same order of magnitude in plasma levels of adenosine and adenine nucleotides. Maximal adenosine increase (84%) was observed at the end of the infusion period, whereas peak plasma levels of ATP and ADP (69 and 55%, respectively) and of AMP (61%) were detected 10 and 5 min after discontinuation of infusion, respectively. Although the exact mode of action of buflomedil at the molecular level remains unclear, some indirect findings suggest that the increase in adenosine may be due to enhanced release rather than to inhibition of cell uptake. Because such activity of buflomedil consists of enhancement of physiologic mechanisms of vasodilation and tissue protection occurring in the course of ischemic events, new pharmacologic perspectives for the drug may arise.

Adenine Nucleotides↗