Biomedical subjects

L Parisi

Publications and source records attributed to L Parisi.

At least 19 recordsLinked to original sources

PubMed2006

Conversion from mild cognitive impairment to Alzheimer's disease is predicted by sources and coherence of brain electroencephalography rhythms.

Objective. Can quantitative electroencephalography (EEG) predict the conversion from mild cognitive impairment (MCI) to Alzheimer's disease (AD)? Methods. Sixty-nine subjects fulfilling criteria for MCI were enrolled; cortical connectivity (spectral coherence) and (low resolution brain electromagnetic tomography) sources of EEG rhythms (delta=2-4 Hz; theta=4-8 Hz; alpha 1=8-10.5 Hz; alpha 2=10.5-13 Hz: beta 1=13-20 Hz; beta 2=20-30 Hz; and gamma=30-40) were evaluated at baseline (time of MCI diagnosis) and follow up (about 14 months later). At follow-up, 45 subjects were still MCI (MCI Stable) and 24 subjects were converted to AD (MCI Converted). Results. At baseline, fronto-parietal midline coherence as well as delta (temporal), theta (parietal, occipital and temporal), and alpha 1 (central, parietal, occipital, temporal, limbic) sources were stronger in MCI Converted than stable subjects (P<0.05). Cox regression modeling showed low midline coherence and weak temporal source associated with 10% annual rate AD conversion, while this rate increased up to 40% and 60% when strong temporal delta source and high midline gamma coherence were observed respectively. Interpretation. Low-cost and diffuse computerized EEG techniques are able to statistically predict MCI to AD conversion.

Aged↗

PubMed2006

Construction of a contig of BAC clones spanning the region of the apple scab avirulence gene AvrVg.

The ascomycete Venturia inaequalis, causal pathogen of apple scab, underlies a gene-for-gene relationship with its host plant apple (Malus spp.). 'Golden Delicious', one of the most common cultivated apples in the world, carries the ephemeral resistance gene Vg. Avirulence gene AvrVg, matching resistance gene Vg has recently been mapped on the V. inaequalis genome. In this paper, we present the construction of a BAC library from a V. inaequalis AvrVg isolate. The library is composed of 7680 clones, with an average insert size of 80kb. By hybridization, it has been estimated that the library contains six haploid genome equivalents. Thus the V. inaequalis genome can be predicted to be approximately 100Mb in size. A chromosome walk, starting from the marker VirQ5 co-segregating with AvrVg, has been performed using the BAC library. Twelve BAC clones were identified during four steps of the chromosome walking. The size of the resulting contig is approximately 330kb.

Ascomycota↗

PubMed2006

Risk behaviours among young people. Evaluation and descriptive analysis.

AIM: Risk behaviours--as they are defined by specialist literature for the damage these behaviours cause to young people's health and/or life--are getting more and more frequent among young people. They range from self-injuring behaviours to the consequences of a precocious, high-risk and/or promiscuous sexual activity, from abnormal eating behaviours to the deaths from fun. METHODS: The inquiry concerned a group of university students (100 males and 100 females), selected at random from the Faculties of Medicine and Surgery, Psychology, Economy and Jurisprudence of the University of Palermo, who were asked to answer a questionnaire composed of 91 questions and structured in 4 sections. The first section regards associate-identifying information; the second one inquires on experiences and requirements concerning sexuality; the third section explores the state of health and the use of drugs and alcohol; the fourth section looks into relations with others. RESULTS: The analysis of our data revealed that young people have different high-risk behaviours (use of drugs and alcohol, non protected sexual intercourse, carelessness for one's and one's partner's serological state); this is associated to poor information, as complained by the people interviewed, on the prevention of sexually transmissible diseases, use of drugs and alcohol. CONCLUSIONS: The conclusion is drawn that the new modalities of the assumption of risk by young people would correspond to the climate of vagueness, lack of limits, meanings and values which characterize the present society.

Adolescent↗

PubMed2005

Abnormal head nociceptive withdrawal reaction to facial nociceptive stimuli in Parkinson's disease.

INTRODUCTION: Trigemino-cervical-spinal reflexes (TCSRs) are complex brainstem stereotyped nociceptive responses involved in a defensive withdrawal reaction of the head from facial nociceptive stimuli. OBJECTIVE: The present study was undertaken to collect data on possible TCSR abnormalities in idiopathic Parkinson's disease (PD) and investigate any correlation with motor signs and L-DOPA administration. METHODS: TCSRs were registered from the semispinalis capitis and biceps brachii muscles after electrical stimulation of the supraorbital nerve in 18 patients with PD and 24 controls. The latency (L) and area (A), as well as the sensory (ST), painful (PT) and reflex (RT) thresholds were measured during the 'off' and 'on' state, and possible correlations with the UPDRS III total score, selected subscores (tremor, neck rigidity, upper limb rigidity, akinesia, rising from a chair, posture and posture instability) and duration of illness were investigated. RESULTS: Significant changes between controls and PD patients were found in the L, A, PT and RT of TCSRs. These results were not significantly influenced by L-DOPA treatment. A significant correlation was found between neck rigidity, postural instability scores and duration of illness and the TCSR L and A values in PD patients in the 'off' state. CONCLUSIONS: TCSRs abnormalities, combined with dopamine resistance, are consistent with a primary loss of brainstem neurons mediating a complex sensory-motor integration including neck muscle tone and postural control as well as the head withdrawal reaction to the nociceptive stimuli. SIGNIFICANCE: TCSRs may represent a useful tool for the assessment of brainstem sensory-motor function in PD as well as other movement and degenerative disorders.

Aged↗

PubMed2005

Probing glaucoma visual damage by rarebit perimetry.

AIM: To compare rarebit perimetry (RBP) with standard achromatic perimetry (SAP) in detecting early glaucomatous functional damage. METHODS: 43 patients with ocular hypertension (OH), 39 with early primary open angle glaucoma (POAG), and 41 controls were considered. Visual fields were assessed using the Humphrey field analyser (HFA) 30-2 and RBP tests. Differences among the groups were evaluated using Student-Newman-Keuls and chi(2) tests. Correlation between HFA and RBP parameters was assessed using the Pearson's correlation coefficients and regression analysis. Sensitivity and specificity of RBP in detecting early glaucomatous visual damage were calculated with different algorithms. RESULTS: RBP-mean hit rate (MHR) was respectively 88.6% (SD 4.8%) in controls; 79.1% (10.9%) in the OH group; 64.3% (13.8%) in the POAG group (differences statistically significant). Good correlation in the POAG group was found between HFA-mean deviation and RBP-MHR. Largest AROC (0.95) and optimal sensitivity (97.4%) were obtained when an abnormal RBP test was defined as having (at least 1): MHR <80%; >15 areas with a non-hit rate of >10%; > or =2 areas with a non-hit rate of >50%; at least one area with a non-hit rate of > or =70%. CONCLUSIONS: The RBP appeared to be a rapid, comfortable, and easily available perimetric test (requiring only a PC device), showing a high sensitivity and specificity in detecting early glaucomatous visual field defects.

Adult↗

PubMed2005

[The quality of life in developing age subjects with chronic renal diseases].

AIM: Renal pathologies have an hard impact on ill children's life style, psychic and physical development. In the last years, even if medical cures allowed these children to live longer and to have a better quality of life, today both their families and themselves have to face a lot of difficulties due to the kind of pathology. These children show behaviour troubles, bad sociability, aggressiveness, poor school performance, anxiety and depression, and then the subjects with chronic renal failure show a retard in neurological and cognitive development. In this study we evaluated the impact that the chronic renal illness has on children and adolescents' quality life. METHODS: For this study, we have used the Impact of Childhood Illness Scale. It includes 30 questions that value 4 aspects of the child and family's life style: illness and its treatment, impact on the child, impact on parents and impact on the family. For every question, it considers the frequency of the problem and the degree of the worry that it causes. We gave the questionnaire to 47 couples of parents' children who are suffering from chronic renal diseases (19 subjects with nephrotic syndrome, 7 with chronic glomerulenephritis, 10 with chronic renal failure, 5 dialysed, 6 with kidney transplant). All parents compiled the questionnaire. RESULTS: The obtained results showed that developing age subjects, who are affected by chronic renal diseases, can have emotional and behavioural difficulties that have an effect on subject and on his family. Their parents live in a continuous stress state because chronic pain and anxiety cause depression, a sense of inadequacy and frustration. CONCLUSIONS: As in every chronic physical illness, the sick child and his family are obliged to face a series of physical, behavioural and emotional changes. Besides, they are faced by possible collateral effects of the illness and of its treatments on development.

Achievement↗

PubMed2004

[Neuropsychological profiles in preterm low birth weight children].

AIM: Several studies focus on the psychic development of extremely low birth weight (ELBW) preterm infants and highlight the presence of neurological, cognitive and relating disorders. Several contributions have in fact shown that in these subjects in school age disturbances of cognitive functions may be encountered; in particular, disturbances of specific neuropsychological functions, such as attention defects, impaired visuo-spatial function, memory and language have been reported in subjects with a globally normal intelligence quotient. METHODS: Forty-three school-aged children were studied (21 males and 22 females). They had a low birth weight (weight between 1,050-2,450 g), the gestation period was between 29 and 32 weeks and they were compared with a control sample whose birth weight was >2,500 g. Cognitive development was assessed by a test battery including WISC-R, Zazzo "deux Barrage" Test, Benton Visual Retention Test and Frostig Developmental Test of Visual Perception. Parents were also called in to evaluate how they had experienced the birth of their child and how long the mother had been kept in the clinic. RESULTS: The overall analysis of our study suggests normal cognitive development in these children. No significant diffences were detected in the 2 studied groups. The lack of differences could be associated with the criteria used to select our sample because no children with severe perinatal disorders were included in the study. In addition, a good mother-child relationship seems to have been established in these children and this has certainly contributed to cognitive development adequate to their age. CONCLUSION: The prognosis of these children is therefore closely related both to the birth weight and, especially, to the difficulties faced in the neonatal age (severe perinatal diseases).

Cognition Disorders↗

PubMed2003

Early visual function impairment in CADASIL.

The authors carried out genetic analyses and visual electrophysiologic evaluations in six asymptomatic sons and daughters of patients with symptomatic cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL). Three subjects showed Notch3 Cys146Tyr missense mutation and a dysfunction of the outer, middle, and innermost retinal layers, with normal neural conduction in postretinal visual pathways, whereas in the remaining subjects without genetic mutations, no electrophysiologic abnormalities were found. An early vascular retinal impairment in CADASIL may precede the onset of clinical manifestations.

Adolescent↗

PubMed2003

Muscular cramps: proposals for a new classification.

Muscle cramps are involuntary, painful, sudden contractions of the skeletal muscles. They are present in normal subjects under certain conditions (during a strong voluntary contraction, sleep, sports, pregnancy) and in several pathologies such as myopathies, neuropathies, motoneuron diseases, metabolic disorders, hydroelectrolyte imbalances or endocrine pathologies. There has been considerable uncertainty in the literature regarding the classification and nomenclature of muscle cramps, both because the term "cramp" is used to indicate a variety of clinical features of muscles, leading to its use as an imprecise "umbrella" term that includes stiffness, contractures and local pain, and because the spectrum of the diseases in which it appears is wide. The purpose of the present study is to propose a simple classification to provide a framework to better recognize the full spectrum of phenomenology of muscle cramps.

Drug-Related Side Effects and Adverse Reactions↗

PubMed2003

Genetic dissection of partial resistance to race 6 of Venturia inaequalis in apple.

Scab, caused by the fungus Venturia inaequalis, is one of the most important diseases of apple (Malus x domestica). The major resistance gene, Vf, has been widely used in apple breeding programs, but two new races of the fungus (races 6 and 7) are able to overcome this gene. A mapped F1 progeny derived from a cross between the cultivars Prima and Fiesta has bee n inoculated with two monoconidial strains of race 6. These strains originated from sporulating leaves of 'Prima' and a descendant of 'Prima' that were grown in an orchard in northern Germany. 'Prima' carries the Vf resistance gene, whereas 'Fiesta' lacks Vf. A large variation in resistance and (or) susceptibility was observed among the individuals of the progeny. Several quantitative trait loci (QTLs) for resistance were identified that mapped on four genomic regions. One of them was located in the very close vicinity of the Vf resistance gene on linkage group LG-1 of the 'Prima' genetic map. This QTL is isolate specific because it was only detected with one of the two isolates. Two out of the three other genomic regions were identified with both isolates (LG-11 and LG-17). On LG-11, a QTL effect was detected in both parents. The genetic dissection of this QTL indicated a favourable intra-locus interaction between some parental alleles.

Chromosome Mapping↗

PubMed2002

Psychophysiological approach in Parkinson's disease: L-dopa effects on preprogramming and control activity.

To investigate whether preprogramming (Bereitschaftspotential, BP) and control activity (skilled performance positivity, SPP) in a complex task are sensitive to L-dopa, movement related potentials (MRPs) were recorded in 12 non-demented Parkinson's disease (PD) patients before and after acute L-dopa administration, and in 17 control subjects. After L-dopa administration, the PD patients scored a significantly higher percentage of correct performances ( p<0.05), linked to a decreased BP amplitude ( p<0.001) and an increased SPP amplitude ( p<0.005), than before therapy. Our findings suggest that preprogramming activity is impaired in untreated PD patients. Dopaminergic drug administration seems to restore their ability to use more automatic motor strategies which become more similar to that of normal subjects.

Aged↗

PubMed2002

L-dopa effects on preprogramming and control activity in a skilled motor act in Parkinson's disease.

OBJECTIVES: The authors investigated whether preprogramming (Bereitschaftspotential, BP) and control activity (skilled performance positivity, SPP) in a bimanual, sequential skilled performance task (SPT) is sensitive to L-dopa administration in non-demented Parkinson's disease (PD) patients. METHODS: Movement related potentials (MRPs) were recorded in 12 non-demented parkinsonian patients before and after acute L-dopa administration, and in 17 control subjects, all of whom were performing SPT for the first time. BP, SPP and correct performances were evaluated both as a grand average and in sequential blocks in order to verify the learning effect. RESULTS: After L-dopa administration the PD patients scored a significantly higher percentage of correct performances (P<0.05), linked to a decreased BP amplitude (P<0.001) and an increased SPP amplitude (P<0.005), than before therapy. Dynamic evaluation through the block analysis did not show any learning effect in off-therapy patients but showed that L-dopa intake improved learning, linked to a BP amplitude decrease (P<0.005) and a SPP amplitude increase (P<0.05). Furthermore, L-dopa minimized differences in the learning trend between off-therapy PD patients and controls. CONCLUSIONS: Our findings suggest that skilled motor learning is impaired in non-demented untreated PD patients. Dopaminergic drug administration seems to restore the ability of PD patients to use more automatic motor strategies, as demonstrated by the electrophysiological and behavioural pattern, which became more similar to that of normal subjects.

Aged↗

PubMed2002

L-Dopa decreases cutaneous nociceptive inhibition of motor activity in Parkinson's disease.

OBJECTIVES: To estimate changes in motor inhibitory mechanisms at the spinal level in Parkinson's disease (PD) patients by measuring cutaneous silent responses to nociceptive stimuli in the course of L-Dopa therapy. MATERIALS AND METHODS: Fourteen patients with idiopathic PD (Group 1) and 13 patients with other forms of parkinsonism (Group 2) participated in the study. The cutaneous silent period (CSP) from the hand and clinical scores (UPDRS, part III) were measured "off" therapy (T0), after a single dose of L-Dopa (T1) and 3 months after the beginning of L-Dopa daily therapy (T2). RESULTS: At T0 the duration of the CSP was significantly prolonged in Group 1 and Group 2. At T1 and T2 the mean duration of the CSP significantly decreased in Group 1 (P < 0.05) and a significant correlation was found between the shortening of the CSP and the improvement of rigidity and bradikynesia in the upper limb. CONCLUSIONS: Our findings show that L-Dopa decreases the cutaneous nociceptive inhibition of motor activity in PD patients. CSP may be useful to assess L-Dopa responsiveness during the clinical course of PD.

Administration, Oral↗

PubMed2002

First evidence of the breakdown in Belgium of the scab resistance conferred by the Vf gene.

Scab is the most important fungal disease of apple throughout the world. The main breeding programmes are focused on scab resistance conferred by monogenic sources of resistance, specifically the Vf gene originated from Malus floribunda 821. Since 1993, evidence of the breakdown of this resistance mechanism appeared in different countries like United Kingdom, Germany, The Netherlands and France. In 1997, a first evidence of the Vf gene breakdown in Belgium was observed on the cultivar 'Judeline' planted in an untreated orchard at Aubel where a cider making company, with our collaboration, search for cultivars adapted for juice and cider processing. Therefore, a glasshouse experiment was planned in order to characterize which scab race was present. In 1999, the artificial inoculation of some cultivars in controlled conditions showed that the scab race collected the year before at Aubel presented the same characteristics than race 7 described by other works. At the same time, an orchard was established by our Department as planned in an European FAIR project named 'Durable Apple Resistance in Europe' (D.A.R.E) with the aim to study the resistance durability of some partial scab resistant apple cultivars inside an European orchard network. Sixteen repetitions of 20 different cultivars are planted and are originating from 8 participating countries. Five apple clones with specific host resistance towards 4 specific scab races are also present. Incidence and severity assessments of the disease are made 3 times a year on the whole tree according to two international standardized scales. For the first time in 2000, a specific scab race was observed on Malus floribunda 821 which caused very serious injuries. Those results confirm that new breeding strategies must be developed for reducing the risk of scab resistance breakdown in the future.

Belgium↗

PubMed2001

Remodeling of synaptic membranes after induction of long-term potentiation.

Several morphological changes of synapses have been reported to be associated with the induction of long-term potentiation (LTP) in the CA1 hippocampus, including an transient increase in the proportion of synapses with perforated postsynaptic densities (PSDs) and a later occurrence of multiple spine boutons (MSBs) in which the two spines arise from the same dendrite. To investigate the functional significance of these modifications, we analyzed single sections and reconstructed 134 synapses labeled via activity using a calcium precipitation approach. Analyses of labeled spine profiles showed changes of the spine head area, PSD length, and proportion of spine profiles containing a coated vesicle that reflected variations in the relative proportion of different types of synapses. Three-dimensional reconstruction indicated that the increase of perforated spine profiles observed 30 min after LTP induction essentially resulted from synapses exhibiting segmented, completely partitioned PSDs. These synapses had spine head and PSD areas approximately three times larger than those of simple synapses. They contained coated vesicles in a much higher proportion than that of any other type of synapse and exhibited large spinules associated with the PSD. Also the MSBs with two spines arising from the same dendrite that were observed 1-2 hr after LTP induction included a spine that was smaller and a PSD that was smaller than those of simple synapses. These results support the idea that LTP induction is associated with an enhanced recycling of synaptic membrane and that this process could underlie the formation of synapses with segmented PSDs and eventually result in the formation of a new, immature spine.

Animals↗

PubMed2001

Cutaneous afferents mediating the cutaneous silent period in the upper limbs: evidences for a role of low-threshold sensory fibres.

OBJECTIVES: To evaluate the contribution of the low-threshold afferents to the production of the cutaneous silent period (CSP) in the upper limbs. METHODS: The CSP was studied in 10 healthy adults and 4 patients with Friedreich's ataxia. The following neurophysiological aspects were studied: (a) relationship between sensory threshold (ST), sensory action potential (SAP) amplitude and CSP parameters; (b) habituation and recovery cycle of the CSP at different stimulus intensities (2xST and 8xST); (c) pattern of responses in distal and proximal muscles at different stimulus intensities (2xST and 8xST). RESULTS: (a) The CSP occurred at low intensities (1xST and 2xST) and increased abruptly between 3.5xST and 4xST (corresponding to the pain threshold). The SAP amplitude was saturated before CSP saturation. In the patients with Friedreich's ataxia, the CSP appeared only at higher stimulus intensities (6xST-8xST). (b) The CSP evoked at 2xST showed a fast habituation and slow recovery cycle whereas the opposite behaviour was found at 8xST. (c) Low-threshold stimuli induced an inhibitory response restricted to the distal muscles. High-intensity stimulation produced an electromyographic suppression, significantly increasing from proximal to distal muscles. CONCLUSIONS: Our findings support the notion that low-threshold afferents participate in the production of the CSP in the upper limbs. The different afferents may activate different central neural networks with separate functional significance.

Action Potentials↗

PubMed2001

Magnetic resonance imaging findings in piriformis syndrome: a case report.

Piriformis syndrome (PS) is an unusual cause of sciatica that, because of the lack of strict diagnostic criteria, remains a controversial clinical entity. The diagnosis of PS is still primarily clinical because no diagnostic tests have proven to be definitive. We report the case of a 30-year-old woman, affected by a severe scoliosis, who developed a persistent buttock pain resembling that of PS. The clinical suspicion was confirmed by magnetic resonance imaging (MRI) of the pelvis, which showed an enlargement of the left piriformis muscle with an anterior isplacement of the sciatic nerve. The role of MRI in the diagnosis, clinical definition, and therapeutic approach to PS is discussed.

Adult↗

PubMed2000

Visual electrophysiological responses in subjects with cerebral autosomal arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL).

OBJECTIVES: To evaluate visual electrophysiological responses in subjects with cerebral autosomal arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL). METHODS: Three subjects (one male and two females, mean age 55.3+/-2.9 years) belonging to an Italian family already diagnosed with CADASIL through clinicopathological and genetic studies and 14 control subjects (6 males and 8 females, mean age 52.7+/-3.6 years) were enrolled in the study. Flash electroretinogram (ERG), oscillatory potentials (OPs) and simultaneous recordings of pattern electroretinogram (PERG) and visual evoked potentials (VEPs) were assessed in all 3 subjects with CADASIL and age-matched controls. RESULTS: Subjects with CADASIL showed: reduced ERG, OP and PERG (N35-P50, P50-N95) amplitudes with respect to our normal limits; delayed PERG (N35, P50) and VEP (P100) implicit times when compared with our normal limits; and VEP (N75-P100) amplitudes and retinocortical times within our normal limits. CONCLUSIONS: Subjects with CADASIL present a dysfunction in the outer, middle and innermost retinal layers when the index of neural conduction in the postretinal visual pathways is normal. The delay in visual cortical responses observed in subjects with CADASIL may be ascribable to retinal impairment with a possible functional sparing of the postretinal visual structures.

Dementia, Multi-Infarct↗