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Biomedical subjects

G L Lenzi

Publications and source records attributed to G L Lenzi.

At least 19 recordsLinked to original sources
PubMed2003

Carotid endarterectomy and gliofibrillar S100b protein release.

Increased levels of the gliofibrillar S100b protein can be detected during carotid endarterectomy (CEA). Whether the S100b protein increase is marker of brain ischemic sufferance and predictor of cognitive decline is controversial. Twenty-eight patients underwent clinical assessment and cranial computed tomography (CT) 24-48 hours before and 3 months after CEA. S100b serum levels were evaluated before surgery, at cross-clamping, 10 minutes later, at declamping, and 24-48 hours and 10-12 weeks after CEA. Increased S100b levels were detected in 11 patients (39%); eight (73%) of these patients had symptomatic carotid artery disease. Increased S100b level correlated with history of TIA or stroke ( p=0.005), low mini-mental state examination score ( p=0.02), and ischemic infarctions at preoperative CT ( p=0.03). Slight and transient increased S100b levels were detected in 39% of patients during CEA. The protein levels increased despite the absence of clinical events during surgery. Our findings suggest a failure of compensatory hemodynamic or metabolic mechanisms in peri-ischemic tissue, whose longterm effects on cognition remain to be investigated.

Adaptation, Physiological↗
PubMed2003

Longitudinal evaluation of depression and anxiety in patients with clinically isolated syndrome at high risk of developing early multiple sclerosis.

We investigated the relationship between emotional changes, brain lesion burden and development of multiple sclerosis (MS). Thirty-seven consecutive patients with clinically isolated syndrome (CIS) were prospectively assessed with the Expanded Disability Status Scale (EDSS), the 21-item Beck Depression Inventory (BDI), the State-Trait Anxiety Inventory (STAI) and gadolinium enhanced (Gd+) MRI scans. BDI and STAI were also administered to 36 age-matched controls. Conversion to MS was defined as the occurrence of a clinical relapse. CIS patients were more likely to endorse symptoms of anxiety and depression than controls. Baseline scores for depression and anxiety did not correlate with the total lesion load (i.e., volume of Gd+, T2 and T1 lesions) and the number of Gd+ lesions during the first six months of follow-up. A positive correlation was found between severity of depressive scores and the lesion load in the right temporal region (P = 0.005). After 33+/-6 months of the study entry, patients who had a clinical relapse were more frequently depressed (P = 0.001) than those relapse free. Emotional disturbances are frequently observed in CIS patients and show a tendency towards a normalization in relapse-free patients. The increased rate of depressive symptoms observed in patients who developed MS seems to result from a combination of psychological and organic features. The lesion load in the right temporal region is confirmed as a key area for developing depressive symptoms, even in the early phase of the disease.

Adult↗
PubMed2002

Discontinuous-flow plasmapheresis and patent foramen ovale: a possible cause of paradoxical embolism.

A 68-year-old woman was admitted for a subacute polyradiculoneuropathy and submitted to PE. A central right jugular venous access was placed after the third PE procedure due to a failing peripheral blood access. During the fourth PE, performed with a discontinuous-flow system (continuous-flow used for 3 procedures), she developed multiple embolic ischemic lesions in the left middle cerebral artery (MCA) territory. A thorough cerebrovascular screening showed only a patent foramen ovale (PFO). In our case, a possible increase of the right atrium blood pressure induced by the positive flux of the discontinuous-flow PE could have been responsible for a paradoxical embolism through the PFO. Plasma exchange (PE) is used in several neurologic disorders. It is commonly thought to be a relatively safe procedure. However, a number of adverse events may occur: paradoxical embolism has not been reported to occur.

Aged↗
PubMed2002

A case-control study on Alzheimer's disease and exposure to anesthesia.

Aretrospective hospital-based case-control study was performed with the aim to evaluate the association between exposure to anesthesia and Alzheimer's disease (AD). A total of 115 AD patients, 230 Parkinson's disease (PD) patients and 230 patients with non-degenerative neurological disease were studied. Each AD case was matched for sex, age (+/-3 years) and geographic area of residence with four controls (2 PD patients and 2 with other neurological disease). Information about exposure to general anesthesia and other variables was gathered through hospital records. No associations were found between the risk of AD and the exposure to anesthesia in the 1 and 5 years preceding disease onset, nor between the risk of AD and the number of surgical operations. A significant difference was observed between the mean age of AD patients and controls undergoing surgical procedures. The present study reveals a lack of association between exposure to general anesthesia and AD. Prospective epidemiological studies are needed in order to investigate levels of exposure to anesthesia, as well as any possible relationships between anesthetic exposure and genetic factors (e. g. APOEepsilon4 genotype).

Age Factors↗
PubMed2002

Donepezil in the treatment of hallucinations and delusions in Parkinson's disease.

As cholinergic mechanisms may be at least partially responsible for hallucinations and delusions in Parkinson's disease (PD), we conducted an open study in 8 PD patients to assess the efficacy and tolerability of the cholinesterase inhibitor donepezil, 5 mg at bedtime for two months, in the treatment of these complications. Hallucinations and delusions improved significantly in all patients. Donezepil was overall well tolerated, but a deterioration in motor disability was noted in 2 out of 8 patients.

Aged↗
PubMed2002

Early stages of probable Alzheimer disease are associated with changes in platelet amyloid precursor protein forms.

Previous findings demonstrated an altered pattern of amyloid precursor protein (APP) forms in platelets of Alzheimer disease (AD) patients, compared both with healthy control subjects or patients with non-Alzheimer-type dementia. The present study aims to evaluate whether platelet APP form ratio (APPr) is altered in patients with early stage AD. We selected 40 patients with early stage AD and 40 age-matched healthy controls. Compared with controls (mean+/-SD=0.91+/-0.3), mean APPr was decreased in AD (mean+/-SD=0.46+/-0.26, p<0.0001). Sixteen very mild AD patients (clinical dementia rating=0.5), identified among the AD group, showed a significant decrease of APPr values (mean+/-SD=0.50+/-0.3, p<0.0001). These findings indicate that alteration of APP processing in platelets is an early event and suggest that this assay might be of diagnostic value in differentiating mild AD from normal ageing.

Aged↗
PubMed2002

Cerebral effects of hyperbaric oxygen breathing: a CBF SPECT study on professional divers.

We investigated the effects on cerebral blood flow (CBF) of pure oxygen breathing exposure during dives in a group of professional divers, in both the normobaric (NBO) and the hyperbaric oxygen (HBO) breathing conditions. Using single photon emission computerized tomography (SPECT) and Tc-99m hexamethylpropylenamine oxime (HM-PAO), we studied 10 young divers and six normal volunteers. Divers were studied by SPECT in the NBO and HBO conditions, in two different sessions. The HBO state was obtained in a hyperbaric chamber at 2.8 ATA for 15 min. By ANOVA, we did not observe any significant difference in CBF distribution between controls and divers in both NBO and HBO conditions. By individual analysis, divers showed a decreased CBF in a total of 33 regions of interest (ROIs) during NBO and 46 ROIs during HBO with respect to control values. In particular, two divers showed a remarkable increase in the number of hypoperfused ROIs during HBO (+7 and +5 ROIs, respectively). Pure oxygen breathing exposure in young divers is associated with a patchy distribution of brain areas of hypoperfusion. This phenomenon is more pronounced in the HBO state than in the NBO state. Further studies on CBF are needed to help identify divers potentially prone to harmful oxygen effects.

Adult↗
PubMed2001

Amyloid precursor protein in platelets: a peripheral marker for the diagnosis of sporadic AD.

BACKGROUND: An altered pattern of amyloid precursor protein (APP) forms consisting in a reduced ratio between the upper (130 kDa) and the lower (106 to 110 kDa) immunoreactivity bands has been described in platelets of patients with AD. OBJECTIVE: To evaluate the sensitivity and the specificity of platelet APP forms' ratio (APPr) as a marker for AD. METHODS: Eighty-five patients with probable AD and 95 control subjects (CON), including healthy individuals and neurologic patients, entered the study. Platelet APPr was evaluated by means of Western Blot analysis and immunostaining in the whole platelet homogenate, and calculated by the ratio between the optical density (OD) of the upper (130 kDa) and the lower (106 to 110 kDa) APP immunoreactive bands. RESULTS: Mean APPr levels were decreased in AD patients (mean OD +/- SD = 0.35 +/- 0.18) compared with the CON group (mean OD +/- SD = 0.92 +/- 0.38) (DF 1, 178, p < 0.0001). Accuracy levels measured by Receiver Operating Curve analysis showed that a cut-off level of 0.57 resulted in a sensitivity of 88.2% and a specificity of 89.4%, with an area under the curve of 0.945. APPr levels were significantly associated with disease severity (mild AD versus moderate AD: p < 0.0001; moderate AD versus severe AD: p < 0.05). CONCLUSION: Platelet APPr allowed to differentiate AD from normal aging and other dementing disorders with high sensitivity and specificity. These findings suggest that platelet APPr may be of help as an adjunctive diagnostic tool in clinical practice.

Aged↗
PubMed2001

Amyloid precursor protein in platelets of patients with Alzheimer disease: effect of acetylcholinesterase inhibitor treatment.

BACKGROUND: Amyloid precursor protein (APP) forms with apparent molecular weights of 130, 110, and 106 kd are present in human platelets. It has been demonstrated that Alzheimer disease (AD) is specifically associated with a decreased APP forms ratio in platelets. OBJECTIVE: To investigate whether acetylcholinesterase (AChE) inhibitor treatment modifies the ratio of platelet APP forms in patients with AD. PATIENTS AND METHODS: From a large sample of patients with probable AD, 30 with mild to moderate AD were selected. Each patient underwent a clinical evaluation including the Mini-Mental State Examination (MMSE) and platelet APP forms analysis at baseline and after 30 days. During this interval, 20 of 30 patients with AD were treated with donepezil hydrochloride (5 mg/d), a piperidine phosphate-based cholinesterase inhibitor. Platelets were subjected to Western blot analysis using monoclonal antibody (22C11). The ratio between the immunoreactivity of the higher-molecular-weight APP form (130 kd) and the lower forms (106 and 110 kd) was measured. RESULTS: All patients taking donepezil completed the 30 days of treatment without adverse effects. The platelet APP forms ratio at baseline did not differ between the 2 AD groups (mean +/- SD optical density ratio: untreated AD, 0.47 +/- 0.12; treated AD, 0.38 +/- 0.18), whereas a significant difference was found at follow-up (mean +/- SD optical density ratio: untreated AD, 0.45 +/- 0.17; treated AD, 0.77 +/- 0.29; P<.001). A significant improvement in MMSE scores in treated AD patients was observed from baseline (16.9 +/- 3.8) to 30 days (18.9 +/- 4.42) (P<.009, 30 days vs baseline), but no significant correlation was found in treated AD patients between MMSE score improvement and APP forms/ratio increase (P =.09). CONCLUSIONS: Administration of AChE inhibitors increases the ratio of APP forms in platelets of patients with AD, suggesting a potential effect of AChE inhibitors on APP trafficking or processing in a peripheral cell.

Aged↗
PubMed2001

Diazepam effects on the cerebral responses to tonic pain: a SPET study.

RATIONALE: Pain is a complex phenomenon with a strong affective-emotional component in addition to a sensory-discriminative one. This causes the activation of multiple brain areas, which process different aspects of pain simultaneously. OBJECTIVES: We investigated the effects of diazepam (DZ) on a well-known pattern of brain regions activated by cold, tonic pain stimuli. METHODS: Quantitative cerebral blood flow (CBF) was assessed by single photon emission tomography (SPET) and the Xe-133 inhalatory method, at rest and during tonic pain activation in eight normal, right-handed, male volunteers. The cold pressor test (CPT) was performed by immersion of the left hand in cold water twice, first during CPT alone, and again 30 min after intravenous administration of diazepam (CPT+DZ). RESULTS: During CPT we observed a significant CBF increase in the right thalamus, primary sensory-motor cortex (S1/M1), frontal and temporal regions, and in the left temporal region and anterior cingulate cortex (ACC). During CPT+DZ, the average CBF was significantly lower than during the CPT state (-11%, P<0.05). After normalisation, during CPT+DZ we again observed a significant CBF increase in the right thalamus, S1/M1 and frontal regions, and in the left ACC, though not in the temporal regions. DZ administration first causes a global reduction in CBF, then modifies the pattern of brain activation. CONCLUSIONS: During CPT, activation of the temporal regions has been interpreted as part of the affective-emotional component of pain response. DZ seems to affect the "pain-related" pattern of activation by abolishing the CBF increase in the temporal regions, without, however, modifying the pain perception or determining a sedating effect.

Adult↗
PubMed2001

Frontal lobe dysfunction in essential tremor: a preliminary study.

27 patients with essential tremor (ET) were studied to determine the cognitive feature of this condition. 15 familial cases and 12 cases with a family history Parkinson's disease (PD) were identified. Performances on frontal lobe tasks of ET patients were compared with those of 15 patients with PD and 15 healthy control subjects. The ET patients showed significant impairments both in attentional and conceptual thinking tasks, similar to those observed in the PD group. Despite the nosographic independence of the two conditions, data showed that the frontal lobe feature of ET was similar to those of PD, thus possibly suggesting a common dysregulation of dopamine pathways.

Aged↗
PubMed2001

Aminergic tone correlates of migraine and tension-type headache: a study using the tridimensional personality questionnaire.

BACKGROUND: Aminergic neurotransmitter activity has been studied in many neuropsychiatric diseases by means of a self-administered questionnaire proposed by Cloninger. Given that central aminergic modulation plays a major role in the pathophysiology of primary headaches, we investigated the personality dimensions related to aminergic neurotransmitter activity in patients with migraine and tension-type headache. METHODS: From a consecutive series of 230 patients, we selected those presenting with migraine and tension-type headache according to the International Headache Society criteria. All patients were assessed by means of the Cloninger 100-item self-report Tridimensional Personality Questionnaire and a depression scale. The four dimensions of personality are novelty seeking (dopaminergic), harm avoidance (serotonergic), reward dependence (noradrenergic), and persistence (glutaminergic). RESULTS: One hundred twenty-one patients presenting with migraine and 42 with tension-type headache were recruited. The results indicate significantly higher harm avoidance scores (P<.001) in both patients with migraine and those with tension-type headache than in controls. Furthermore, patients with migraine had a significantly low score in the novelty seeking dimension (P<.001). When we compared only the two groups of patients with headache, we found that the persistence dimension alone was significantly higher in patients with migraine than in those with tension-type headache (P<.05). No differences were observed either in the overall scores of the other personality dimensions or in the depression scale scores. CONCLUSIONS: The Tridimensional Personality Questionnaire results support a role of the serotonergic system in both migraine and tension-type headache pathophysiology. A dysfunction of dopaminergic and glutaminergic tone seems to be a specific feature of migraine.

Adult↗
PubMed2001

Vascular dementia: a cognitive SPET-CBF activation study.

OBJECTIVE: We investigated the pattern of regional cerebral blood flow (rCBF) responses to a cognitive task in vascular patients with and without dementia. METHOD: We studied 8 controls and 18 vascular patients by quantitative rCBF assessed by (133)Xe inhalation method and SPET, both at rest and during a cognitive figure recognition task. Eight were mildly demented and 10 were nondemented vascular patients. According to their task performance, 12 patients were classified as 'good performers' (GPs) and 6 patients as 'poor performers' (PPs). RESULTS: Vascular patients activated a larger number of brain areas than controls. No differences were observed between controls, nondemented and mildly demented patients in the pattern of rCBF activation. GPs presented a lower mean percentage of rCBF increase than either controls or PPs. GPs had lower values than PPs in the left temporal, parietal and occipital regions and in the right posterior cingulate and occipital regions. CONCLUSIONS: These data suggest that vascular patients may functionally compensate for vascular damage by activating more brain areas than controls do and, consequently, by increasing the rate of regional activation.

Aged↗
PubMed2001

Usefulness of primitive reflexes in demented and non-demented cerebrovascular patients in daily clinical practice.

The aim of this study was to investigate the usefulness of primitive reflexes (PRs) as additional alert signs in a routine clinical setting of cognitive decline in an elderly population of chronic ischemic cerebrovascular patients. We considered the occurrence of grasp, palmomental, glabellar and snout reflexes in 75 demented (VaD) and 75 non-demented (VaND) patients, and in 75 healthy elderly controls. We never elicited more than two PRs in controls. The occurrence of three or four PRs provided the strongest correlation with dementia (p < 0.0001), with 93% specificity irrespective of low sensitivity. In conclusion, the occurrence of more than two PRs might serve as an additional warning sign of possible mild cognitive impairment in chronic ischemic cerebrovascular patients.

Aged↗
PubMed2000

Identification of lacunar infarcts before thrombolysis in the ECASS I study.

BACKGROUND: The identification of lacunar infarcts before thrombolysis would make it possible either to exclude them from treatment or to show that they also may benefit from it. OBJECTIVE: To determine whether clinical presentation or early CT findings of patients enrolled in the first European Cooperative Acute Stroke Study (ECASS I) trial would identify lacunar infarcts before treatment. METHODS: Predictive values, sensitivity, specificity, and accuracy of clinical presentation as pure motor hemiparesis (PMH) or sensorimotor stroke (SMS) syndromes and of baseline CT findings in predicting lacunar infarcts were calculated in the ECASS I patients. RESULTS: Of 514 patients, 44 placebo (17%) and 44 recombinant tissue plasminogen activator (rt-PA) (18%) patients had PMH/SMS involving at least two of three areas. Thirty-one placebo (12%) and 32 rt-PA (13%) patients had PMH/SMS involving three areas. The 7-day CT was compatible with a lacunar infarct in 32 placebo (12%) and 44 rt-PA (18%) patients. PMH/SMS involving at least two areas had a positive predictive value of 30% both in placebo and rt-PA patients, whereas positive predictive values of the involvement of three areas were 23% and 31%. Those of absence of early CT signs were 21% and 30%, and those of leukoaraiosis or previous lacunar infarcts were 21% and 23%. Positive predictive values of PMH/SMS involving at least two areas combined with absence of early CT signs were 36% in placebo and 33% in t-PA patients, and those of PMH/SMS plus leukoaraiosis or previous lacunes were 28% and 7%, respectively. CONCLUSIONS: In the ECASS I trial, lacunar infarcts were not recognizable on clinical grounds, and early CT findings, alone or in combination with the clinical picture, added poorly to the differential diagnosis.

Cerebral Infarction↗