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C Giorgi

Publications and source records attributed to C Giorgi.

At least 73 records · Page 4Linked to original sources
PubMed1991

Sequences and coding strategies of the S RNAs of Toscana and Rift Valley fever viruses compared to those of Punta Toro, Sicilian Sandfly fever, and Uukuniemi viruses.

The sequences and coding strategies of the S RNAs of two viruses, Toscana (TOS) and the M12 derivative of Rift Valley fever ZH-548 (RVF, Phlebovirus genus, Bunyaviridae) have been determined from cDNA clones and compared to the previously published sequences of Punta Toro (PT), Sandfly fever Sicilian (SFS), and Uukuniemi (UUK) viruses. All five viruses exhibit an ambisense coding strategy for their small (S) RNA species, i.e., one gene product (the NSs protein) is encoded in the 5' half of the viral RNA, a second (the N protein) is encoded in the sequence complementary to the 3' half. The terminal nucleotides of the S RNAs of the five viruses are comparable through 13-14 residues. The 3' and 5' ends of these S RNAs have inverted complementary compositions. Three phleboviruses (TOS, SFS, and RVFV) exhibit comparable G-rich, centrally located intergenic sequences, albeit of different lengths. These sequences have a number of similar motifs at, or immediately following, the end of the coding regions, motifs that may be involved in their S mRNA transcription termination processes. The other two viruses (UUK, PT) have AT-rich intergenic sequences that have the potential to form secondary structure. They lack the G-rich sequences or particular sequence motifs recognized in the other three virus RNAs. The deduced sizes of the TOS and RVFV N proteins are 27,704 and 27,430 kDa (respectively). Their NSS proteins are 36,677 and 29,903 kDa (respectively). When aligned, the deduced sequences of the N proteins of the five viruses exhibit homologies ranging from 54 to 30%. The order of homology to RVFV N protein is PT greater than TOS greater than SFS greater than UUK; to TOS N protein it is PT greater than or equal to RVF greater than SFS greater than UUK. The sequences of the NSS proteins are less similar, with values ranging from 30 to less than 17%. The order of homology to RVFV NSS is SFS greater than PT greater than TOS greater than UUK. Due to these more distant relationships, the homologies to TOS NSS protein are less clear.

Amino Acid Sequence↗
PubMed1991

Combined treatment modality for medulloblastoma in childhood: effects on neuropsychological functioning.

8 long-surviving children, treated for medulloblastoma with combination radiotherapy and chemotherapy after surgery were examined in order to assess general intelligence, immediate attention and prolonged attention. Their siblings or first cousins were selected as controls. The children with medulloblastoma performed significantly worse than their peers, both in intelligence tests and attention tests. A trend towards a positive correlation between age at the start of treatment and IQs was confirmed in our study, while there was no evidence of a correlation between IQs and time elapsed from therapy. The role of chemotherapy, radiotherapy and their combination effect in producing neuropsychological sequelae is discussed.

Adolescent↗
PubMed1990

Comparative accuracy of the vectorcardiogram and electrocardiogram in the localization of the accessory pathway in patients with Wolff-Parkinson-White syndrome: validation of a new vectorcardiographic algorithm by intraoperative epicardial mapping and electrophysiologic studies.

The scalar electrocardiograms (ECGs) and vectorcardiograms (VCGs) of 41 patients with Wolff-Parkinson-White (WPW) syndrome were used to compare the accuracy of these techniques in the identification of the site of preexcitation. The location of the accessory pathway (AP) was determined by endocavitary electrophysiologic studies in all patients and the location was confirmed during intraoperative epicardial mapping in 28 of them. The ECGs were classified according to Gallagher's criteria and with Milstein's algorithm, whereas the VCGs were classified according to a new two-step algorithm. The presence of multiple accessory pathways and coexisting myocardial infarctions were major limitations in both the VCG and ECG classification procedures. In patients with a single accessory pathway, three AP localizations (right free ventricular wall, posterior, or left free ventricular wall) were identified with the first step of the VCG algorithm, with an overall sensitivity (96.5%), specificity (90.7%), and positive predictive values (80%) that were greater than those obtained with the ECG Milstein algorithm (77.1%, 91.5%, and 75%, respectively). The second step of the VCG algorithm made it possible to identify an AP location in one of the following sites: anterior right, lateral right, posterior right, posterior left, lateral left, or anterior left ventricle. The overall sensitivity, specificity, and positive predictive values were greater for the second step of the VCG algorithm than for the ECG criteria proposed by Gallagher (43.6% versus 39.3%, 92.1% versus 87.4%, and 51.5% versus 33.3%, respectively). It was concluded that the VCG seems to be more specific and sensitive than the ECG in the identification of the preexcitation site and should be given preference in the initial evaluation of the WPW syndrome.

Adult↗
PubMed1990

Long-term results of percutaneous retrogasserian thermorhizotomy for "essential" trigeminal neuralgia: considerations in 1000 consecutive patients.

Long-term results (average follow-up, 9.3 years) obtained in 1000 consecutive patients suffering from cryptogenetic ("essential") trigeminal neuralgia treated with percutaneous thermorhizotomy are analyzed. Pain relief was obtained in 95% of the treated patients. Permanent morbidity was as follows: masseter weakness in 105 patients; oculomotor palsies in 5 patients; weakening of the corneal reflex in 197 patients, 6 of whom requested an ocular operation for keratitis; and painful dysesthesia in 52 patients, 15 of whom developed a painful anesthesia syndrome. There was a recurrence rate of 18.1%, and a correlation between postoperative sensory deficit and the cure rate was found. These results are discussed and compared to the results obtained with different techniques.

Aged↗
PubMed1990

Guided microsurgery by computer-assisted three-dimensional analysis of neuroanatomical data stereotactically acquired.

Stereotactic acquisition of neuroradiological data, followed by identification of cerebral structures and three-dimensional rendering, has been successfully applied to guided microsurgical resection of deep-seated cerebral lesions. The method described utilizes data from magnetic resonance, computed tomography, and digital angiography and allows the surgeon to 'wire frame' the lesion volume and the position of cerebral vessels and structures of high functional relevance. Three-dimensional rendering of surgical instrumentation around the reconstructed anatomy allows for planning and simulation of the trajectory of approach.

Adolescent↗
PubMed1990

Efficacy of oral sotalol in suppression of premature ventricular complexes and analysis of its beta-adrenergic blocking activity.

The efficacy of oral DL-sotalol in suppressing premature ventricular complexes was assessed by Holter recordings in 28 patients during short term (two weeks) and long term (two years) trials, and its beta-adrenergic blocking effects were evaluated by heart rate response to the Bruce treadmill stress test and plasma catecholamine increases upon active standing. Sotalol produced a significant decrease (more than 85%) in the number of premature ventricular complexes, during both short term (54%) of patients) and long term (39% of patients) trials. The doses employed in this study (320 mg/day) produced mild to moderate degrees of beta-adrenergic blockade as suggested by: a 20% reduction in the mean heart rate on 48 h Holter monitoring (P less than 0.0005); a 15 to 30% reduction in tachycardia induced by strenuous exercise; and a 12% reduction in standing-induced tachycardia. Under long term sotalol therapy the increase in plasma noradrenaline concentrations in response to active standing was not modified, but the increase in plasma adrenaline concentrations was greater than under baseline conditions (P less than 0.025). Both systolic and diastolic blood pressures significantly increased during long term sotalol administration (P less than 0.005 and P less than 0.025, respectively). However, blood pressure remained within the normotensive range during sotalol therapy. It was concluded that sotalol provides, at effective antiarrhythmic doses, a satisfactory level of beta-adrenergic blockade which during standing was associated with significant changes in adrenaline plasma increments.(ABSTRACT TRUNCATED AT 250 WORDS)

Administration, Oral↗
PubMed1989

Computer-assisted planning of stereotactic neurosurgical procedures.

To extend the advantages of stereotactic localization to open procedures, a computational device with a graphic output is introduced. It is designed to be used in the operating room, where it processes neuroradiological information (CT, MR, and angiography) acquired under stereotactic conditions. The surgeon can interact with neuroanatomical data, extracting borders of structures of surgical relevance. The resulting sets of outlines, shown tridimensionally within the reference of a stereotactic head holder, are presented with respect to the planned approaching trajectory. Color-coded high-resolution graphics show the relationship between lesions and normal brain structures and guide the surgeon's access to deep-seated lesions through small exposures.

Humans↗
PubMed1989

Cell kinetic investigations in brain tumors studied by serial stereotactic biopsy.

Between July 1983 and July 1986, 109 consecutive patients affected by brain tumors and selected for stereotactic biopsy underwent in vitro investigation of cell kinetics. The potential proliferative activity of these different neoplasms, evaluated as in vitro 3H-thymidine labeling index (LI), has been determined in 46 mature astrocytomas, 19 anaplasic astrocytomas, 25 glioblastomas, 5 cystic craniopharyngiomas, 6 metastatic tumors, 4 primary C.N.S. lymphomas, 3 pineal germinomas and one choroid plexus papilloma. The relevance of LI on prognosis has been evaluated in 35 patients affected by glial tumors with adequate follow-up longer than 2 years. This retrospective study allowed us to demonstrate the prognostic value of LI in mature astrocytoma and anaplasic astrocytoma series. The feasibility of LI determination by in vitro procedure has been demonstrated also in non-neuroectodermal tumors. In craniopharyngioma the LI investigations allowed to demonstrate a peculiar topographic arrangement of cells in S phase.

Adolescent↗
PubMed1989

Long term efficacy and toxicity of amiodarone in the treatment of refractory cardiac arrhythmias.

Amiodarone has remarkable efficacy, but it also has a high incidence of severe side effects. Nevertheless, it is extensively used. The findings of an amiodarone treatment follow-up period of one to 72 months (mean 19 +/- 17) in 95 patients with recurrent life threatening arrhythmias resistant to other antiarrhythmic drugs are described. The mean loading dose of 800 mg/day for one week was followed by an average dose of 600 mg/day for two weeks. The long term daily dose was 400 mg in 80 patients and 200 mg in the remaining 15 patients. Amiodarone was particularly effective in suppressing complex ventricular arrhythmias. It also decreased premature ventricular beats by 83% and atrial premature beats by 41%. Supraventricular tachycardias were completely controlled and the ventricular response to atrial fibrillation was slowed. Twelve of the 95 patients (12.6%) died while taking amiodarone, two of sudden death and 10 of heart failure. Side effects were recorded in 77 (81%) patients. They were generally dose related and subsided with a decrease in dose or discontinuation of the medication. There was a correlation between the concentration of rT3 and the significance of the side effects. Thirty-nine patients stopped taking amiodarone, however, only 14 of these stopped because of toxicity: five developed pulmonary fibrosis; three had neurological toxicity; two had bradyarrhythmias; two developed hepatic dysfunction; one had hypothyroidism; and one patient suffered an aggravation of a pre-existent heart failure. It was concluded that amiodarone is a very effective treatment for supraventricular and ventricular arrhythmias. However, it does have numerous and severe side effects.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1989

Sympatho-adrenal and cardiovascular responses during hand-grip in human hypertension.

Circulating norepinephrine and epinephrine levels were correlated with echocardiographic indices of cardiovascular function during isometric exercise (hand-grip at 30% of maximum force for 3 minutes) in 19 patients with mild essential hypertension and 9 normotensive subjects. At the end of the third minute of exercise, plasma norepinephrine and epinephrine, blood pressure and heart rate, increased significantly and similarly in both groups of patients. In contrast, peripheral resistance tended to increase in hypertensives but tended to decrease in normotensives. Moreover, indices of ventricular function increased in normotensives but decreased in hypertensives. At the end of the exercise, systolic and diastolic blood pressures were directly correlated with epinephrine levels in normotensives but were correlated only with norepinephrine levels in hypertensives. On the other hand, norepinephrine and epinephrine levels were inversely correlated with changes in indices of left ventricular performance in hypertensive patients only. These results demonstrate that during isometric exercise, the increase in blood pressure in normotensives is associated with a sympatho-adrenal activation of cardiac performance and contractility, while in hypertensives the increase in blood pressure results mainly from an increase in peripheral resistance associated with a reduction in cardiac performance and contractility, despite a similar sympatho-adrenal activation in both groups. These differences in the hemodynamic responses may be compatible with the hypothesis of beta-adrenoceptor desensitization or structural alterations of the cardiovascular system in hypertensive patients.

Adrenal Glands↗
PubMed1988

Serial stereotactic biopsy of brain stem expanding lesions. Considerations on 45 consecutive cases.

Fourty-five patients affected by brain stem expanding lesions underwent serial stereotactic biopsy between 1978 and 1986. The definitive histological diagnosis allowed the definitive treatment of extrinsic tumours and non-neoplastic lesions. In patients affected from glial tumours the serial stereotactic biopsy allowed the histological grading and the definition of the growth modalities at the superior boundaries of the tumours. These data have been utilized to guide the choice of treatment. The future perspectives of stereotactic biopsies are discussed in view of the therapeutic results obtained in this series and in other series reported in the literature.

Adolescent↗
PubMed1988

Lysosomal enzymes in experimental allergic encephalomyelitis: time course and evidence of the source.

The lysosomal enzymes acid proteinase and beta-glucuronidase, were assayed in spinal cords of rats during the course of experimental allergic encephalomyelitis (EAE). Histological and histochemical examination was carried out versus controls, in selected areas of the same cords biochemically assayed, to look at the distribution of the lysosomal enzyme acid phosphatase. The biochemical assay showed a significant increase of the enzyme activities during the disease and the increase was significantly correlated with the intensity of the disease. The distribution in the nervous tissue of the increase in acid phosphatase activity observed in animals with EAE, suggests that endogenous nervous cells may contribute to the lysosomal enzyme increase in EAE.

Animals↗
PubMed1988

Demonstration of hysteresis in refractoriness of canine ventricular myocardium.

The properties and determinants of hysteresis during ventricular effective refractory period (VERP) measurements by an extrastimulus technique were determined in 15 anesthetized open-chest dogs as well as in isolated ventricular muscle (n = 6). VERP was determined both by decreasing the S1-S2 interval and also by increasing S1S2. Hysteresis was then calculated by subtracting the VERP obtained with the decreasing S1S2 from the VERP obtained with the increasing S1S2. The effects of basic cycle length, pulse width, stimulation intensity, and the number of basic drives on VERP and hysteresis were evaluated. VERP was shorter for long pulse width, high stimulation intensities, and shorter basic cycle lengths. These modifications were not associated with significant changes of hysteresis. VERP was shorter during decreasing S1S2 than during increasing S1S2. Hysteresis was greater with 6 basic drive cycles than with 12 (P less than 0.001) in both in vivo and in vitro preparations. The data suggest that 1) hysteresis occurs during VERP measurements; 2) hysteresis is independent of stimulation modality; and 3) hysteresis decreases with the number of basic drive cycles.

Animals↗