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Biomedical subjects

S M Gaini

Publications and source records attributed to S M Gaini.

At least 19 recordsLinked to original sources
PubMed2007

Skin-derived stem cells transplanted into resorbable guides provide functional nerve regeneration after sciatic nerve resection.

The regeneration in the peripheral nervous system is often incomplete and the treatment of severe lesions with nerve tissue loss is primarily aimed at recreating nerve continuity. Guide tubes of various types, filled with Schwann cells, stem cells, or nerve growth factors are attractive as an alternative therapy to nerve grafts. In this study, we evaluated whether skin-derived stem cells (SDSCs) can improve peripheral nerve regeneration after transplantation into nerve guides. We compared peripheral nerve regeneration in adult rats with sciatic nerve gaps of 16 mm after autologous transplantation of GFP-labeled SDSCs into two different types of guides: a synthetic guide, obtained by dip coating with a L-lactide and trimethylene carbonate (PLA-TMC) copolymer and a collagen-based guide. The sciatic function index and the recovery rates of the compound muscle action potential were significantly higher in the animals that received SDSCs transplantation, in particular, into the collagen guide, compared to the control guides filled only with PBS. For these guides the morphological and immunohistochemical analysis demonstrated an increased number of myelinated axons expressing S100 and Neurofilament 70, suggesting the presence of regenerating nerve fibers along the gap. GFP positive cells were found around regenerating nerve fibers and few of them were positive for the expression of glial markers as S-100 and glial fibrillary acidic protein. RT-PCR analysis confirmed the expression of S100 and myelin basic protein in the animals treated with the collagen guide filled with SDSCs. These data support the hypothesis that SDSCs could represent a tool for future cell therapy applications in peripheral nerve regeneration.

Action Potentials↗
PubMed2006

Clinical correlates and cognitive underpinnings of verbal fluency impairment after chronic subthalamic stimulation in Parkinson's disease.

A decline in verbal fluency is the most consistent neuropsychological sequela of deep brain stimulation (DBS) for Parkinson's disease. We assessed clinical correlates and switching and clustering subcomponents in 26 parkinsonians undergoing subthalamic DBS. Post-surgical motor improvement was accompanied by worsening at both letter and category fluency tasks. Total number of words and switches decreased, while average cluster size was unchanged. Worsening tended to be prominent in patients with baseline poorer cognitive status and more depressed mood. Impairment of shifting suggests prefrontal dysfunction, possibly due to disruption of fronto-striatal circuits along the surgical trajectory and/or to high frequency stimulation itself.

Aged↗
PubMed2006

Vertebral artery dissection in a child. Is "spontaneous" still an appropriate definition?

Though a rare cause of stroke in the general population, in almost one quarter of young patients affected by stroke cervical artery dissection (CAD) is the underlying cause. Among these cases "spontaneous" dissections, intended as non-traumatic, represent about 34% of posterior circulation arterial dissection in patients aged less than 18 years. We here describe the case of a seven-year-old boy who developed a spontaneous vertebral artery dissection (VAD) leading to occipito-mesial, thalamo-capsular and cerebellar infarction. Once a traumatic origin was excluded, clinical history and laboratory findings were further analysed: fever associated with tonsillitis during the previous week, raised inflammatory indices, a throat culture positive for beta haemolysing Streptococcus group A and high titres of streptococcal antibodies were found. This case suggests that patients with CAD referred as spontaneous deserve extensive analysis. Subjects presenting with a dissection and an underlying infection are likely to have a hyperinflammatory response (although further experience is needed). In these patients immediate start of antibiotic therapy, treatment with anti-inflammatory drugs and further a lifelong prophylaxis with antibiotics before any invasive procedure are strongly recommended.

Brain Infarction↗
PubMed2005

APOE influences vasospasm and cognition of noncomatose patients with subarachnoid hemorrhage.

OBJECTIVE: To determine the influence of the APOE genotype on functional and cognitive outcome and on the incidence and prognosis of clinical vasospasm (delayed ischemic neurologic deficit [DIND]) in noncomatose patients with aneurysmal subarachnoid hemorrhage (SAH). METHODS: The authors reviewed the data of patients admitted for SAH to the Neurosurgical Departments of the San Gerardo Hospital of Monza (January 1996 to December 2001) and the Ospedali Riuniti of Bergamo (January 2002 to September 2003). The authors considered only noncomatose patients and evaluated outcome by means of the Rankin Disability Index and the Mini-Mental State Examination at least 6 months after the SAH. STATISTICAL ANALYSIS: Uni- and multivariate logistic regression. RESULTS: The authors included 101 patients. They found the epsilon4 allele in 26 patients (25.7%). The presence of the epsilon4 allele negatively affected the overall outcome (functional morbidity or cognitive morbidity, or both) (p = 0.0087) and, particularly, cognitive morbidity (p = 0.0028). Those with an epsilon4 allele had delayed ischemic neurologic deficit DINDs more frequently (p = 0.024) and, in the presence of DIND, they were more likely to show permanent neurologic deficits (p = 0.0051). CONCLUSIONS: ApoE4 negatively affects cognitive morbidity and delayed ischemic neurologic deficit recovery. The presence of an epsilon4 allele increases the risk of delayed ischemic neurologic deficit.

Adult↗
PubMed2004

The headache in the Emergency Department.

The headache is a very frequent symptom and represents the 0.36%-2.5% of all reasons of claim to Emergency Department. Even if it is rarely related to high risk diseases, it is mandatory to promptly differentiate life-threatening conditions. In order to establish a correct diagnostic and therapeutic pathway and ask for aimed specialistic consultation, the emergency physician must be familiar with the various categories of headache. It is important to distinguish between essential headache and secondary headache. All patients presenting to the emergency department with the complaint of headache should be interviewed carefully regarding their history. The quality of pain associated with the intensity, location, rate, duration, modality of onset, relieving or worsening conditions, response to drugs, symptoms or signs associated must be investigated as well. Careful neurological examination including the vision of fundus oculi and the evaluation of rigor nucalis can provide further important diagnostic information. Laboratory exams do not usually give significant issues in the majority of patients with headache. However, dosage of inflammation index can be useful when an infective or inflammatory disease is suspected. CT scan can rule-out the suspicion of organic intracranial causes. When the physician suspects meningitis or subarachnoid hemorrhage (SAH) not showed by CT scanning, rachicentesis can turn out diagnostic. The modality of onset, clinical characteristics and differential diagnosis of subarachnoid hemorrhage, intracranial hypertension, colloidal cyst of the third ventricle, trigeminal neuralgia, temporal arteritis and pituitary adenomas and apoplexy will be discussed. These diseases are not only of neurological and neurosurgical interest, but involve also the physician in the Emergency Department.

Adenoma↗
PubMed2003

Brain flow changes before and after deep brain stimulation of the subthalamic nucleus in Parkinson's disease.

Deep brain stimulation (DBS) of the subthalamic nucleus (STN) markedly improves motor symptoms and reduces medication needs in Parkinson's disease (PD) patients. However, its effect on brain function has remained unclear. We used SPECT and the tracer ECD to measure regional cerebral blood flow before and 6 months after DBS of the STN in 22 PD patients and 13 healthy controls. PD patients were divided into good and poor responders to DBS, if changes in "off" UPDRS motor scores after surgery were >60% or <40%, respectively. Statistical analysis was performed using the SPM99 software. At baseline, all PD patients showed significant perfusion reductions in cortical areas (premotor frontal, parietal, and occipital). After DBS, changes were normalized only in the good responders, while cortical defects in the poor responders were unchanged. No flow decrements were detected in basal ganglia and thalamus in both groups, suggesting that DBS does not have a "lesion-like" effect. We conclude that good surgery outcome is associated with normalization of cortical flow abnormalities in PD.

Case-Control Studies↗
PubMed2003

Deep brain stimulation for the treatment of Parkinson's disease: the experience of the Neurosurgical Department in Monza.

deep brain stimulation is a widely accepted surgical therapy for the symptomatic treatment of advanced parkinson's disease; high frequency chronic stimulation of the subthalamic nucleus proved its efficacy to control the major motor symptoms. In the neurosurgical department of Monza we treated 72 parkinsonian patients (November 1998-January 2003). One year follow-up results are: decrease of tremor 90%, hypertonous 56%, bradykinesia 70%, voice impairment amelioration 30%, mean total daily L-dopa intake reduced 58%. Freezing and balance did not ameliorate, some voice impairment and psychic derangement have been observed. Major surgical complications were: haemorrage (1 case - transient hemiparesis), infections (2 cases), pulmonary embolisation (1 case). To optimise the surgical results, careful clinical and instrumental selection of the patients are mandatory before surgery.

Clinical Trials as Topic↗
PubMed2003

Functional neuroimaging (PET and SPECT) in the selection and assessment of patients with Parkinson's disease undergoing deep brain stimulation.

Deep brain Stimulation (DBS) is an effective treatment for patients with advanced Parkinson's disease (PD) and motor complications who can no longer be improved by adjustment of medical therapy. Selection of surgery candidates and follow-up after surgery are critical for good outcome. Functional neuroimaging can help in the clinical assessment of these patients. We have used single photon emission computed tomography (SPECT) and the tracer ECD to measure regional cerebral blood flow before and 6 months after DBS of the subthalamic nucleus (STN) in 20 patients with advanced PD. We found a significant increase in the anterior cingulate/supplementary motor cortex in the 12 good responders (change in off unified UPDRS >50%). Conversely, patients with poor response (n=8; change in off UPDRS-III <50% following DBS) revealed a significant worsening of cortical hypoperfusion particularly in the prefrontal areas. No flow decrements were detected in the basal ganglia and in the thalamus in both groups during DBS stimulation suggesting that DBS does not have a "lesion like" effect. If DBS stimulates and does not inactivate STN projection neurons, flow reduction in the poor responders may be secondary to increased inhibitory basal ganglia output.

Cerebrovascular Circulation↗
PubMed2001

Stenting of atherosclerotic stenoses of the extracranial carotid artery.

BACKGROUND: Percutaneous transluminal angioplasty (PTA) and stenting seems to be, at present, the treatment of choice for early restenosis after endarterectomy and for atherosclerotic stenoses of supra-aortic trunks near or at the ostium. In contrast, the role of PTA and stenting for treatment of symptomatic and asymptomatic atherosclerotic stenosis of carotid bifurcation is still debated. METHODS: The present study comprises 27 consecutive cases of atherosclerotic lesions of the carotid bifurcation treated with PTA and stenting. All patients were symptomatic, except for 2 suffering from asymptomatic stenosis with contralateral carotid occlusion. There were 23 stenoses occluding 70% or more of the lumen according to the NASCET criteria and 4 mild stenoses (50-60% of the lumen) with large type C ulcers. Criteria for exclusion from surgery in these cases were aged >79 years, previous neck surgery for laryngeal cancer, carotid bifurcation at C2, association with intracranial aneurysms, occlusion of the contralateral carotid artery, and heart, lung and kidney diseases. All procedures were performed under local anaesthesia associated with mild sedation in a few cases. In all cases, self-expandable stents (Wallstent) were used. Follow-up ranged from 6 to 37 months. FINDINGS: Transient neurological deficit occurred in 3 cases (11%). One case (3.7%) experienced a minor stroke at three months. Asymptomatic tight restenosis due to intimal hyperplasia occurred in one case (3.7%). In 8 cases (40%) of complex stenosis involving common and internal carotid arteries there was some loss of contact of the stent with the wall of the common carotid artery in the late follow-up. One case (3.7%) experienced severe and prolonged hypotension and bradycardia during the release of the stent. INTERPRETATION: From literature data and our results it emerges that periprocedural catastrophic embolism is unlikely to occur. The best results are undoubtedly obtained when treating stenosis limited to the internal carotid artery. Nevertheless, the ideal stent to treat vessels of different calibre, as occurs at the carotid bifurcation, is not yet available. The problem of periprocedural cerebral protection has not been resolved. Reported series are heterogeneous and retrospective, and an adequate follow-up of cases is still lacking.

Adult↗
PubMed2001

Accuracy of stereotactic localisation with magnetic resonance compared to CT scan: experimental findings.

BACKGROUND: Stereotactic localisation of proper targets can be obtained with Magnetic Resonance imaging (MRI), pending correction of the well-known inaccuracy of MRI in reproducing exact geometrical dimension. The aim of the experimental work was to determine the real extent of the MRI distortion and to correct it. METHODS: PVC phantoms and fixed human brains were used as target simulators: stereotactic targeting was obtained with CT and MRI: the results were compared and, finally, the real stereotactic values were measured on a commercial stereotactic device. To optimise MRI targeting it was necessary to abate the "chemical-shift", to modify the head-coil receiver (tuning the "off-resonance" frequencies) and to correct the targeting directly on the images (especially for the Y axis values); careful quality control and environmental tests were also necessary to maintain good performances along the time. RESULTS: 172 measurements were carried out using both CT, plain X-ray and MRI on PVC phantom. The values obtained from CT were considered as reference. Significant geometrical accuracy was found with CT targeting, except for the Z co-ordinate, due to the slice thickness. Mean value differences between the targets on MRI and their real geometric position are about 1 mm on X and Z axises and about 2 mm on Y axis. Similar results were obtained on fixed brains, where absolute values of X and Y co-ordinates of the simulators were measured using a millimetre grid placed over the brain slice. INTERPRETATION: Experimental findings concerning stereotactic targeting with MRI suggest accuracy adequate for clinical practice, even when extreme geometrical precision is required, such as in radiosurgery or functional stereotaxy. Careful quality control and intensive experimental setting of the MRI device are mandatory to obtain satisfactory results.

Data Interpretation, Statistical↗
PubMed2001

Physiologic study of the subthalamic volume.

Deep brain stimulation (DBS) obtains good control of advanced PD symptoms. Chronic stimulation of Stn may alleviate rigidity, dyskinesia and tremor. Anatomical and functional intraoperative mapping are mandatory to obtain careful target localisation. Per-operative macrostimulation was carried out in 22 patients undergoing bilateral DBS in Stn; a volume 6 mm above to 4 mm below Stn was explored. Positive, collateral and adverse effects were recorded every 2 mm. Results obtained during acute stimulation were correlated to anatomical data from stereotactic atlases. Our findings suggest a volume, encompassing the zona incerta, Forel's fields and the lowermost part of anterior thalamus, functionally homogeneous to Stn. In fact, the stimulation of this volume obtains reduction of PD symptoms comparable to Stn.

Aged↗
PubMed2000

Introduction of GDC embolization in the clinical practice as treatment synergical to surgery: impact on overall outcome of patients with subarachnoid hemorrhage.

The GDC endovascular approach represent an effective alternative to surgery for treatment of intracranial aneurysms. Anyway no data are available about the impact of endovascular embolization with GDC on overall outcome of patients with subarachnoid hemorrhage. We analyse retrospectively a series of 234 patients admitted for ruptured intracranial aneurysm. Results were then compared with results of three surgical series from the literature. The 95.7% of patients underwent aneurysm treatment; 56.4% of patients were classified as good recovery, 12.8% presented moderate disability, 10.3% were severely disabled, 3% were in persistent vegetative state and 17.5% were dead. Patients older than 60 years accounted for 37% of all cases and good outcome in this group accounted for 54.7%. Good results were obtained in 90.1%, 61.7% and 22.8% of patients with Hunt-Hess grade I-II, III and IV-V respectively. Finally good outcome was observed in 82.8% of patients with aneurysms of the posterior circulation. Introduction of GDC embolization in clinical practice contributed to the extension of indication for aneurysm treatment leading to a reduction of overall mortality. GDC utilisation does not affect the overall percentage of patients with good outcome reflecting an increase of severely disabled patients. Endovascular treatment seems an effective theraputic choice in selected grade I-II patients. Results in grade III patients suggest that surgery may be advantageous because of washing and decompression of the basal cisterns while results in grade IV and V patients are unsatisfactory. GDC embolization clearly improves the prognosis of patients with posterior circulation aneurysms and probably is an advantageous theraputic choice in elderly patients.

Adolescent↗
PubMed1999

Surgery and stenting As combined treatment of a symptomatic tandem stenosis of the carotid artery.

International co-operative studies have demonstrated a benefit from surgery for symptomatic and asymptomatic patients affected by internal carotid artery stenosis of 60-70%. The presence of a tandem lesion, intracranial or extracranial, may annul the benefit of surgery. Such patients may thus represent a challenging problem for management if age, good general conditions and a normal neurological status favour a therapy. A 54-year-old man developed transient ischaemic attacks of the left hemisphere; his general condition was good, and neurological status was normal. Angiography showed a tight stenosis at the left common carotid artery near the ostium and at the homolateral carotid bifurcation. At first, a self-expanding wall stent was placed at the level of the common carotid artery stenosis, and immediately after a standard endarterectomy under general anaesthesia was performed. The postoperative course was normal and was complicated only by the presence of a mild deficit of the hypoglossal nerve due to the presence of a high bifurcation. The early and late outcome of our case suggests that stenosis of the proximal common carotid artery may be successfully treated by stenting. While awaiting additional data about this new technology, endovascular techniques and surgery may be complementary in the management of patients suffering from such tandem lesions.

Angioplasty, Balloon↗
PubMed1999

[What kind of monitoring of intracranial pressure].

Intracranial pressure monitoring is an essential element of severe head injury monitoring. In the Italian reality, this monitoring still has not become diffusely utilised. In this paper are analysed, using the available data obtained from the Neurolink database, the information from the more advanced Italian neurotrauma centres. Only 50% of the patients, in which monitoring is indicated, are monitored. Synthetically will be reviewed the indications to the monitoring, the advantages offers from such procedure, the modalities of monitoring considering also the economic impact and the risks legacies to the procedure.

Craniocerebral Trauma↗
PubMed1998

Jugular saturation (SjvO2) monitoring in subarachnoid hemorrhage (SAH).

Jugular saturation (SjvO2) monitoring was performed in 26 SAH patients to evaluate the incidence of normal (0.56-0.74) and pathological SjvO2 values in this population and to describe its time course in the first 12 days. We also attempt to quantify the influence of systemic and cerebral hemodynamics on SjvO2 and to assess the relationship between cerebral injury volume measured on CT scan and SjvO2. Mean SjvO2 was 0.66 +/- 0.07 (354 samples, median 0.67, range 0.43-0.89). 73% of the observations (259/354) were in the normal range. On serial measurements, we identified only 37/354 (10%) desaturation episodes (D.E.). ICP was significantly higher during low SjvO2 observation (p = 0.008). No statistical differences were noted regarding the influence of MAP, CPP, PaCO2, PaO2 on SjvO2 but during D.E., lower PaCO2 and CPP were more frequently observed. CT scan lesions > 25 ml were associated initially with lower SjvO2 values and with higher values at second CT.

Adult↗
PubMed1998

Neuroendocrine, immunohistochemical, and ultrastructural study of pineal region tumors.

Thirteen patients with tumors in the pineal region were submitted to pre- and post-operative blood sampling (08:00, 14:00, 20:00, and 02:00 hr) for three or four consecutive days. A single cerebrospinal fluid (CSF) sample was collected at surgery, and melatonin levels determined. In all patients, serum and CSF beta subunit of human chorionic gonadotrophin (betaHCG), carcino embryonic antigen (CEA), and alpha-fetoprotein (AFP) levels were measured. Histology revealed four pineocytomas, one pineoblastoma, four germinomas, one immature teratoma, one pilocytic astrocytoma, one lymphoma, and one meningioma. Serum and CSF levels of serological biomarkers were normal, except for one of the germinoma cases. In most patients, alteration either in the circadian rhythm or in the melatonin concentration was observed before surgery. In benign neoplasms the circadian rhythm was conserved. In pineoblastoma, lymphoma, and three out of four germinomas, melatonin concentrations were undetectable. In one case of germinoma, melatonin levels were high, with the circadian rhythm being abolished. According to conventional histology, all germinomas were similar. Therefore, in a rare case of pineal germinoma with high melatonin levels, the tissue was subjected to an in depth investigation (immunohistochemical and ultrastructural) in order to determine the pathology and the possible differences from the other typical germinomas. Results were compared to those provided from other pineal neoplasms. Electron microscopy examination detected the presence of clusters of intermediate filaments and numerous electrondense granules only in the case of a germinoma producing melatonin.

Adult↗