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Biomedical subjects

G Orlandi

Publications and source records attributed to G Orlandi.

At least 19 recordsLinked to original sources
PubMed2006

Analysis of aneusomy level and HER-2 gene copy number and their effect on amplification rate in breast cancer specimens read as 2+ in immunohistochemical analysis.

Our aim was to determine the aneusomy level and the HER-2 gene copy numbers, by fluorescence in situ hybridization (FISH) and to analyze their impact on the amplification rate in breast carcinomas considered HER-2 weakly positive cases by immunohistochemistry. We evaluated 343 breast carcinomas using double colour FISH (LSI Her-2/neu gene and CEP 17). Monosomy and polysomy were demonstrated in 24.2% and 46.1% respectively and 101/343 (29.6%) of the specimens were amplified by FISH. A statistically significant difference was observed, when we compared the amplification percentage in polysomic and monosomic specimens (P<0.0001) and, among polysomic specimens, when tumours were compared with HER-2 gene signals number per cell between 3 and 10 and >10 respectively (P<0.0001). Logistic regression analysis showed that HER-2 signals >10 and polysomy absence were independently associated with amplification. Our results confirm that the majority of 2+ IHC cases express the HER-2 protein without gene amplification and highlight the effect of chromosome 17 aneusomy and the HER-2 gene copy number on amplification.

Breast Neoplasms↗
PubMed2006

Chromatic pattern-reversal electroretinograms (ChPERGs) are spared in multiple system atrophy compared with Parkinson's disease.

Idiopathic Parkinson's disease (IPD) patients have abnormal visual evoked potentials (VEPs) and pattern electroretinograms (PERGs), attributed to dopaminergic transmission deficiency in visual pathway, probably the retina. VEP abnormalities are not reported in multiple system atrophy (MSA). The aim of this study was to investigate and compare chromatic (Ch) red-green (R-G) and blue-yellow (B-Y), and luminance yellow-black (Y-Bk) PERGs in patients with MSA and IPD. We investigated 6 MSA patients (mean age: 62+/-7.4 years) not undergoing any pharmacological treatment, as well as 12 early IPD patients (mean age: 60.1+/-8.3 years) and 12 age-matched normal observers. ChPERGs were recorded monocularly in response to full-field equiluminant R-G, B-Y and Y-Bk horizontal gratings. In MSA only responses to R-G stimuli showed minimal insignificant changes (slight but not significant amplitude reduction without any significant latency delay); no significant abnormality was detected for B-Y and luminance Y-Bk stimuli. By contrast, in IPD all responses were reduced in amplitude and delayed in latency, above all for B-Y stimuli. Present data indicate that both chromatic and achromatic PERGs are virtually unaffected in MSA, whereas in early IPD they are clearly impaired, suggesting different pathogenic retinal mechanisms and a useful simple tool for distinguishing MSA from IPD.

Aged↗
PubMed2006

The extent of right-to-left shunt fails to correlate with severity of clinical picture in migraine with aura.

Several investigations have documented an increased incidence of right-to-left shunt (RLS) in migraine with aura (MA) and have emphasised its role in the physiopathology of aura; so far, however, no data are available concerning a possible correlation between the extent of the RLS and the clinical picture of MA patients. To investigate the possible relationship between the extent of the RLS, revealed by the number of microbubbles (MB) detected during transcranial Doppler with IV injection of ultrasound contrast (TCDc), and the clinical characteristics of MA (age at first onset of migraine, mean annual frequency of attacks and mean duration of the aura phase), 30 consecutive patients with typical aura and migraine headache positive on TCDc evaluation for RLS were enrolled. Permanent RLS was found in 12 patients and latent RLS was found in 18 patients; of these, 6 had a high-grade RLS, 5 medium-grade RLS and 7 low-grade RLS. No correlation has been documented between the number of MBs and the clinical parameters of both patients with latent shunts and those with permanent ones, nor between the clinical parameters of the two groups of patients. These data show that RLS does not seem to affect the clinical manifestation of MA and that the extent of RLS fails to correlate with the severity of the clinical picture of the disorder.

Adult↗
PubMed2005

Rizatriptan does not change cerebral blood flow velocity during migraine attacks.

Rizatriptan represents a major advance in the treatment of migraine attack: inhibition of peripheral trigeminal nerve and constriction of intracranial extracerebral blood vessels have been proposed as its main antimigraine mechanisms of action. Although many studies may suggest that rizatriptan causes highly selective vasoconstriction within intracranial extracerebral vessels (i.e., meningeal arteries), no literature data are available to date on possible cerebral hemodynamic changes in humans after treatment with rizatriptan. The aim of this study was to evaluate the effect of rizatriptan on cerebral blood flow velocity performing transcranial Doppler during spontaneous attacks of migraine without aura. Fourteen patients suffering from migraine without aura were monitored to evaluate mean flow velocity changes on both middle cerebral arteries during migraine attack 30 min before and 120 min after oral administration of rizatriptan 10mg. Monitoring was repeated for 30 min during the pain-free period. All patients turned out to be drug responders and no significant mean flow velocity changes were observed between the pain-free period and pre-treatment phase; besides no significant difference in mean flow velocity value have been detected between the periods after the drug administration during the attack versus both pre-treatment period and pain-free phase. These findings indicate that the antimigraine action of rizatriptan is not associated with clear intracranial cerebral hemodynamic changes and may support its cerebrovascular safety.

Adult↗
PubMed2005

Electrophysiological evidence by single fibre electromyography of neuromuscular transmission impairment in a case of Miller Fisher syndrome.

Miller Fisher syndrome is an autoimmune neuropathy characterised by ataxia, areflexia and ophthalmoplegia, with minimal if any limb weakness, and in the majority of cases by high titres of IgG anti-GQ1b ganglioside antibodies. In vitro electrophysiological experiments have demonstrated that these antibodies induce a transmission blockade at neuromuscular junction either pre- or post-synaptically. We report the case of a 63-year-old man with MFS that shows blood serum negative for anti-GQ1b but presents an impairment of neuromuscular transmission detected by single fibre electromyography. To the best of our knowledge, this represents the first case in the literature using jitter technique and suggests that other antibodies may be involved in the function of motor end plates by bindings to the synaptic membranes.

Electric Stimulation↗
PubMed2005

C-erb-2 gene amplification and chromosomal anomalies in bladder cancer: preliminary results.

Studies recently suggested that different genetic factors are involved in the development and progression of bladder cancer. In this study, 30 consecutive patients affected by bladder neoplasm were evaluated in order to analyze the frequency of c-erb-2 gene amplification and chromosome 7, 9, 17 aneusomy using fluorescence in situ hybridization (FISH) technique. C-erb-2 gene amplification, chromosome 17 gain and aneusomy were respectively observed in 3.7% (1/27), in 47% (12/27) and in 74% (20/27) of examined tumors. Moreover, chromosome 7 and 9 aneusomy were detected in 74% (20/27) and in 72% (16/27) of specimens. A statistically significant correlation was observed between chromosome 17 aneusomy and tumor stage and grade (r: 0.642, p = 0.0001; r: 0.385, p = 0.04, respectively). In conclusion, we observed a low incidence of C-erb-2 gene amplification, while chromosome 17 aneusomy was confirmed as a marker of advanced and aggressive bladder cancer.

Aged↗
PubMed2004

Saturation and electron-beam lifetime in a storage ring free-electron laser.

We present a phenomenological treatment of free-electron laser storage ring saturation dynamics. The model includes longitudinal instabilities, Touschek intrabeam scattering, and nonzero off-energy-function contributions. The model predictions are compared with Super ACO experimental results and the agreement is shown to be satisfactory.

Journal Article↗
PubMed2004

Intra-arterial thrombolysis in basilar artery occlusion and recent haemorrhagic stroke due to arteriovenous malformation.

We report the case of a young patient suffering from a severe ischaemic stroke due to basilar artery occlusion occurring during selective digital subtraction angiography. This examination was performed in order to assess an arteriovenous malformation in posterior cerebral artery territory responsible for haemorrhagic stroke occurring 17 days before. Intra-arterial thrombolysis with urokinase was performed and basilar artery recanalization was obtained 8 h after stroke onset. Despite the severe neurological impairment, the prolonged symptoms of ischaemia and the high bleeding risk due to the recent cerebral haemorrhage in the same vascular territory involved in thrombolysis, the treatment determined a very favourable clinical outcome.

Adult↗
PubMed2003

Electrophysiological evaluation of genito-sphincteric dysfunction in multiple system atrophy.

Thirteen patients with multiple system atrophy underwent multimodality neurophysiological evaluation, including sphincteric needle electromyography (EMG), sacral reflexes, pudendal nerve terminal latency, pudendal (PSEPs) and tibialis posterior nerve somatosensory evoked potentials (TPSEPs), and perineal motor evoked potentials (PMEPs). EMG revealed denervation or neurogenic changes, with reduction in spontaneous tonic activity at rest and abnormal pudendal nerve terminal latency in 10 patients (76.9%); anal reflex was delayed in 7 patients (53.8%). TPSEPs scalp responses were clearly abnormal in 4 patients (30.7%), whereas PSEPs exhibited changes in 9 (69.2%): in 6 patients responses were delayed at lumbar level (46.2%), and in 5 over the scalp (38.4%). PMEPs showed an increase in latency with a mild prolongation of central motor conduction time (CMCT) in 2 cases (15.3%); 1 patient had prolonged latencies following both cortical and sacral stimulation, but a normal CMCT. Even if diagnostic yield is not improved using these investigations they provide evidence of multiple lesion sites other than Onuf's nucleus.

Aged↗
PubMed2002

Incidence of intracranial hypertension related to jugular bulb oxygen saturation disturbances in severe traumatic brain injury patients.

OBJECTIVE: To analyze the Intracranial Hypertension (IH) development related to jugular bulb oxygen saturation (SjO2) disturbances in severe traumatic brain injury patients (sTBI). MATERIALS AND METHODS: One hundred and thirty-five sTBI patients were reviewed. Those without IH at admission (n = 116) were included. All patients underwent ICP and SjO2 continuous monitoring. Two groups were distinguished according to the SjO2 values during the first 24 hours. Group A: those with abnormal SjO2 (SjO2 more than 75% or less than 55%) and Group B: those with normal SjO2 (55-75%). Differences in IH development and outcome between groups were analyzed. Causes of abnormally low SjO2 were identified. RESULTS: IH developed in 56.9% of patients, between 12 and 48 hours from admission. Group A had a significantly higher incidence of IH than Group B (p < 0.001) and it also had a worse outcome than Group B (GOS 1-2) (p < 0.005). Patients from Group A had a risk of IH 4.5 fold higher than Group B. Considering only patients who developed IH, an abnormal SjO2 value increased 2.3 fold the risk of death compared to those without SjO2 disturbances. Main causes of SjO2 desaturation were hyperventilation (40.7%), hypovolemia (28.4%) and anemia (21%). CONCLUSIONS: Early detection of disturbances in oxygen supply-demand relationship and prevention or resolution of the secondary insults which produce these disturbances, might lead to a reduction in the incidence of intracranial hypertension.

Brain Injuries↗
PubMed2002

Dissection and atherosclerosis of carotid arteries in the young: role of the apolipoprotein E polymorphism.

Twenty-seven young (<50 years old) patients with spontaneous carotid artery dissection in 11 cases and carotid atherosclerosis in 16 cases were evaluated to determine the apolipoprotein E polymorphism. At the DNA analysis the epsilon3/epsilon3 genotype was observed in all patients with dissection, in 13 of 16 (81.2%) patients with atherosclerosis and in 27 of 30 (90%) controls. Three of 16 (18.8%) patients with atherosclerosis and 3 of 30 (10%) controls presented with the epsilon4/epsilon3 genotype, and this difference was not statistically significant. Moreover, observation of the epsilon4/epsilon3 genotype was not significantly higher in patients with atherosclerosis compared with those with dissection. No homozygote epsilon4/epsilon4, epsilon2/epsilon2 or heterozygote epsilon2 genotype was observed. No correlation was found between the presence of the epsilon4/epsilon3 genotype and vascular risk factors. Therefore, the epsilon4 allele seems to be involved in carotid premature atherosclerosis development whereas it may appear to be protective for artery dissection occurrence. A larger sample size is needed to support this suggestion.

Adult↗
PubMed2001

Measurements of coherent diffraction radiation and its application for bunch length diagnostics in particle accelerators.

Measurements of coherent diffraction radiation from a slit of variable width generated by short electron bunches were performed in millimeter and submillimeter ranges. Experimental data are compared with the transition radiation case and theoretical predictions. A more realistic description than the conventional theory is necessary to account for the data correctly. No noticeable difference in the estimated bunch length was observed using diffraction radiation in a wide range of slit widths and transition radiation.

Journal Article↗