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Biomedical subjects

L Bonanni

Publications and source records attributed to L Bonanni.

14 recordsLinked to original sources

Visual hallucinations in Parkinson's disease: clues to separate origins.

Our paper discusses two experimental studies suggesting that Visual Hallucinations (VH) in Parkinson's Disease (PD) may have separate origins. The first is a prospective 8years study evaluating the appearance of VH, visual abnormalities assessed by Visual Evoked Potentials (VEPs) and REM sleep Behaviour Disorder (RBD), in 80 PD patients treated with l-Dopa and Dopaminoagonists (DA). In chronically treated, cognitively unimpaired, PD patients VH were statistically related (p=0.001) to RBD occurrence and high DA doses. Visual abnormalities were significantly reduced by l-Dopa or DA intake, and were statistically unrelated to VH. The second study involved PD patients placed in a Virtual Reality Environment, to decontextualize visual input. When motor symptoms worsened and VEP abnormalities developed patients consistently described hallucinatory dysperceptions of the virtual environment. The two studies therefore show that VH can occur in two seemingly distinct conditions, one is related to chronic treatment and to a sleep disorder frequently observed in PD, the other is probably related to a hypodopaminergic state. Our studies support a recently proposed integrative model of VH, and show that the neural circuits purported to explain VH must include the retinal dopaminergic system and the REM sleep regulatory system.

Antiparkinson Agents↗

Prognostic significance of admission levels of troponin I in patients with acute ischaemic stroke.

OBJECTIVES: Successful prediction of cardiac complications early in the course of acute ischaemic stroke could have an impact on the clinical management. Markers of myocardial injury on admission deserve investigation as potential predictors of poor outcome from stroke. METHODS: We prospectively investigated 330 consecutive patients with acute ischaemic stroke admitted to our emergency department based stroke unit. We analysed the association of baseline levels of cardiac troponin I (cTnI) with (a) all-cause mortality over a six month follow up, and (b) in-hospital death or major non-fatal cardiac event (angina, myocardial infarction, or heart failure). RESULTS: cTnI levels on admission were normal (lower than 0.10 ng/ml) in 277 patients (83.9%), low positive (0.10-0.39 ng/ml) in 35 (10.6%), and high positive (0.40 ng/ml or higher) in 18 (5.5%). Six month survival decreased significantly across the three groups (p<0.0001, log rank test for trend). On multivariate analysis, cTnI level was an independent predictor of mortality (low positive cTnI, hazard ratio (HR) 2.14; 95% CI 1.13 to 4.05; p = 0.01; and high positive cTnI, HR 2.47; 95% CI 1.22 to 5.02; p = 0.01), together with age and stroke severity. cTnI also predicted a higher risk of the combined endpoint "in-hospital death or non-fatal cardiac event". Neither the adjustment for other potential confounders nor the adjustment for ECG changes and levels of CK-MB and myoglobin on admission altered these results. CONCLUSIONS: cTnI positivity on admission is an independent prognostic predictor in acute ischaemic stroke. Whether further evaluation and treatment of cTnI positive patients can reduce cardiac morbidity and mortality should be the focus of future research.

Acute Disease↗

Decreased integrin gene expression in patients with MS responding to interferon-beta treatment.

Interferon-beta (IFN-beta) ameliorates disease course in a subset of patients with MS. The reasons for heterogeneity of clinical responses, however, are unclear. We assessed possible effects of IFN-beta on the gene expression of the leukocyte adhesion molecules VLA-4 and LFA-1 during the first year of treatment of 50 patients with relapsing-remitting MS who showed differential clinical responses. We observed a significant reduction of VLA-4 (P=0.002) and LFA-1 (P=0.03) mRNA expression compared to baseline in first-year clinical responders (n=22). In contrast, first-year IFN-beta non-responders (n=28) had unchanged levels of VLA-4 and LFA-1. In vitro treatment of PBMC with IFN-beta indicated a direct effect on transcription of the integrins' genes. Transcriptional downmodulation of adhesion molecules during IFN-beta treatment may contribute to its mode of action in MS.

Adjuvants, Immunologic↗

Short-term dynamics of circulating T cell receptor V beta repertoire in relapsing-remitting MS.

To understand the short-term dynamics of the circulating T cell receptor V beta (TCRBV) repertoire in relapsing-remitting multiple sclerosis (MS), we monitored the TCRBV profiles of untreated MS patients and healthy controls. Expansions of TCRBV genes in MS patients were significantly more frequent than in controls (P<0.001), were predominantly oligoclonal (80%) and were significantly correlated with immune responses to myelin basic protein (MBP) (P<0.02) and with inflammatory disease activity detected by magnetic resonance imaging (MRI) (P<0.05). Autoreactive T cell responses against myelin antigens may be implicated in perturbations of TCR repertoire in untreated MS patients, detectable even in the absence of clinically evident manifestations.

Adult↗

Low-dose oral methotrexate treatment in chronic progressive multiple sclerosis.

We aimed to further assess the safety and efficacy of low-dose oral methotrexate (LDOM) treatment for chronic progressive MS (CPMS). We studied 20 CPMS patients, including 16 with secondary progressive MS who had shown disease progression in the previous year. The mean follow-up was 23 months. The mean EDSS score was 6.3+/-1.1 before treatment and 6.4+/-1.1 after one year of treatment. At one year, 15 of 20 patients were still being treated, and 10 were stable. Twelve patients have completed 18 months of treatment, and eight are stable. Two patients stopped treatment because of side effects, two more because they did not perceive benefit, and one was lost to follow-up. Six patients had mild, transient increases in liver enzymes not requiring treatment interruption, and two had localized herpes zoster. Magnetic resonance imaging (MRI) performed before treatment and at one year remained unchanged in responders. We confirm that LDOM is safe in carefully selected and monitored CPMS patients. MTX is inexpensive and, given its anti-inflammatory and immunomodulatory properties, may be used as add-on therapy in non-responders to interferon beta, although hepatic toxicity may be a problem in long-term treatment.

Adult↗

Switch-over from tolcapone to entacapone in severe Parkinson's disease patients.

Forty patients affected by severe Parkinson's disease (PD) were treated with tolcapone as an adjunctive therapy to L-DOPA, for 3-7 months, until this drug was discontinued because of side-effects (2 diarrhoea, one of them with orthostatic hypotension, 2 increments of liver enzymes) or because of mandatory indications of the European drugs authority. All patients, after 3-6 months of L-DOPA therapy adjustments, received entacapone for 3 months again followed by withdrawal. L-DOPA daily dosage was significantly reduced by tolcapone and entacapone (p = 0.01 and 0.05). "On" time was increased by 15% during tolcapone treatment (p < 0.05), and by 8% during entacapone treatment. "Off" time was decreased by 16% during tolcapone and by 7% during entacapone treatment. Entacapone was withdrawn in the same patient who experienced diarrhoea and orthostatic hypotension during tolcapone because of recurrence of side-effects, in 6 patients because of increment of dyskinesias (with hallucinations) and in 1 patients because of rhythmic, jerking myoclonus.

Aged↗

RANTES production and expression is reduced in relapsing-remitting multiple sclerosis patients treated with interferon-beta-1b.

RANTES (regulated upon activation, normal T-cell expressed and secreted), a CC chemokine, appears to play a role in the pathogenesis of relapsing-remitting multiple sclerosis (RR-MS), enhancing the inflammatory response within the nervous system. We have demonstrated that RANTES production is increased in RR-MS compared to controls. Interferon-beta-1b (IFN-beta-1b) treatment reduces RANTES production in sera and peripheral blood adherent mononuclear cell (PBAM) supernatants both in relapse and remission. IFN-beta-1b also reduces RANTES expression in PBAM. Our results suggest that RANTES modulation might represent one of the mechanisms of action of IFN-beta-1b in RR-MS.

Adjuvants, Immunologic↗

Leucopenia induced by low dose clozapine in Parkinson's disease recedes shortly after drug withdrawal. Clinical case descriptions with commentary on switch-over to olanzapine.

Four patients affected by severe Parkinson's disease developed leucopenia (900-1200 WBC) during treatment of psychosis (3) or untreatable insomnia (1) with clozapine (37.5-75 mg/day). Clozapine withdrawal was followed by recovery of leucopenia (4000-6000 WBC) in two weeks with no need for the administration of leucokines. After 1-6 months olanzapine was administered (increasing the dose from 2.5 to 10 mg/day) to treat persisting disturbances, but the drug induced severe worsening of parkinsonism and also this drug had to be withdrawn.

Aged↗

Reliability assessment of a gas chromatographic method for polycyclic aromatic hydrocarbons in olive oil.

A quality control test was developed for a gas chromatographic method to determine polycyclic aromatic hydrocarbons in olive oil. Fifteen oil specimens were fortified with eight three- to six-ring polycyclic aromatic hydrocarbons at levels of between 3.0 (approximate detection limit) and 360 micrograms/kg. Three sets of five equally fortified specimens were obtained and assayed at random by three operators. For each fortification level, the means of recovery yield were in the range 56-107%, and were independent of the polycyclic aromatic hydrocarbon congener specificity and the operator's capability. Excluding subsets of data associated with both the fortification level at the detection limit and a deviant polycyclic aromatic hydrocarbon term (benzo[ghi]perylene), an overall mean accuracy of 96% and a precision of 7% were achieved.

Chromatography, Gas↗

Purchasing infant shoes: attitudes of parents, pediatricians, and store managers.

Questionnaires designed to collect data about the purchase of shoes for normal infants were completed by 104 parents in a university ambulatory unit, 127 practicing pediatricians, and 36 shoe store managers. Infants received their first pair of walking shoes at an average age of 8.1 months (range: 4 to 12 months) and at an average cost of $14.56 (range: $2 to $43). Most of these shoes had laces (95%), high tops (87%), hard soles (74%), and special arch supports (50%). Of the 104 children, 73 had shoes before they were walking (average cost: $13.21) and 35 wore walking shoes before they were even standing (average cost: $12.68). Parents obtained much more information about shoes from friends and relatives than from physicians. Those parents who obtained most of their information from salespersons spent the most for shoes. The average cost of shoes recommended by store managers was $18.74. Although 77% of pediatricians felt that inexpensive canvas sneakers are adequate, only 28% of the salespersons and 37% of the parents believed that wearing sneakers is healthy.

Attitude↗

Donepezil, rivastigmine, and vitamin E in Alzheimer disease: a combined P300 event-related potentials/neuropsychologic evaluation over 6 months.

The latency of P300 "cognitive" event-related potentials changes if cholinergic activities of the central nervous system are pharmacologically manipulated. We tested the hypothesis that the new cholinesterase inhibitors donepezil (DPZ) and rivastigmine (Riv) may have an effect on the frequently abnormal P300 component in patients with Alzheimer disease (AD), thereby allowing a significant evaluation of cholinesterase inhibitors. We evaluated 60 patients with mild to moderately severe probable AD, in comparison with 60 age-matched control subjects, with P300 recordings and neuropsychologic examinations. Forty patients were randomly assigned in a double-blinded trial to 5-10 mg/d DPZ versus 2,000 IU/d vitamin E, and 20 patients were instead treated in an open trial with 1.5 to 12 mg/d Riv. In patients treated with vitamin E, we observed latency increments (7.4 +/- 3.5 msec) correlated with worsening neuropsychologic test scores. In patients treated with DPZ and Riv, we found significant P300 latency reductions (15.3 +/- 3.2 msec and 22.0 +/- 3.3 msec). Shorter P300 latencies were associated with higher Wechsler Adult Intelligence Scale scores and with lower AD Assessment Scale-cognitive subscale (ADAS-cog) scores (R = 0.72). Correlations between ADAS-cog changes and P300 changes significantly separated patients treated with DPZ and Riv from those treated with vitamin E. Administration of DPZ and Riv reduced the latencies of P300 components proportionately to neuropsychologic test improvements. Combined P300 and neuropsychologic test evaluation significantly separated DPZ-treated patients and Riv-treated patients from vitamin E-treated patients.

Aged↗