Biomedical subjects

C Giorgi

Publications and source records attributed to C Giorgi.

At least 37 records · Page 2Linked to original sources

PubMed2000

The cerebellum contributes to higher functions during development: evidence from a series of children surgically treated for posterior fossa tumours.

We present data on the intellectual, language and executive functions of 26 children who had undergone surgery for the removal of cerebellar hemisphere or vermal tumours. The children with right cerebellar tumours presented with disturbances of auditory sequential memory and language processing, whereas those with left cerebellar tumours showed deficits on tests of spatial and visual sequential memory. The vermal lesions led to two profiles: (i) post-surgical mutism, which evolved into speech disorders or language disturbances similar to agrammatism; and (ii) behavioural disturbances ranging from irritability to behaviours reminiscent of autism. These data are consistent with the recently acknowledged role of the cerebellum as a modulator of mental and social functions, and suggest that this role is operative early in childhood.

Adolescent↗

PubMed1999

Immunological characterization of Toscana virus proteins.

The genome of Toscana virus (Bunyaviridae family, Phlebovirus genus) consists of three single stranded RNA segments (L, M, S), with negative polarity. The L and M segments contain a single ORF in viral complementary sense and the S segment contains two ORFs in "ambisense" orientation. The M segment codes for three proteins in 3'-5' genomic orientation: a 30 kDa non structural protein and two 65 kDa glycoproteins, GN, and GC. In this paper we report the expression in E. coli of the S segment ORFs and of three regions of the L ORF. The expressed proteins were used to produce monospecific polyclonal antibodies in mice. By using these antibodies the N and the NSs proteins were unequivocally assigned to the S viral-complementary and viral-sense ORFs, respectively, and the L protein to the L ORF. We have found that like N and L proteins, NSs protein is associated with the viral nucleocapsids in mature virions, suggesting its possible involvement in early events of viral replication. NSs protein was also found associated with cellular polysomes. In virus-infected cells the anti-L antibodies recognized proteins shorter than the full-length L protein, possibly products of L subgenomic segments. Interestingly these defective products were not found in mature virions, suggesting specific mechanisms in virion assembly.

Antibodies, Viral↗

PubMed1999

Effects of physical training on straightening-up processes in patients with Parkinson's disease.

PURPOSE: The aim of this study was to evaluate whether motor training could improve the straightening-up sequences in patients with Parkinson's disease and, consequently, could ease the capacity of the patients to change body's position. METHODS: Twenty out-patients with idiopathic Parkinson's disease (12 males, 8 females; mean age 72.9; H-Y, 1. 5-3) were enrolled in a rehabilitation programme which included exercises for the mobility of the trunk, of upper and lower limbs and of each segment of the spine, in order to improve the coordination of movement and to avoid postural disturbances. They received 1 hour of group treatment twice a week for a 5 week consecutive period. No changes were made in the pharmacological treatment received by each patient. The patients were evaluated at the beginning and at the end of the rehabilitation training. The statistical evaluation was made using the Wilcoxon test. RESULTS: Statistically significant differences were observed in all the motor parameters that were evaluated (supine to sitting and sitting to supine, supine rolling, standing from a chair). CONCLUSIONS: The observations demonstrate that physical training can be effective in improving motor performance related to changes in position which affects the simple daily activities of the patients.

Aged↗

PubMed1999

Detection of Toscana virus-specific immunoglobulins G and M by an enzyme-linked immunosorbent assay based on recombinant viral nucleoprotein.

An enzyme-linked immunosorbent assay (ELISA) based on the recombinant Toscana virus nucleoprotein (rN) has been developed. Its sensitivity and specificity for the detection of virus-specific immunoglobulins G and M in human sera were similar to those of the ELISA that is based on an antigen extracted from infected mouse brain and that is routinely used for serodiagnosis.

Animals↗

PubMed1998

Induction of the heat-shock response by antiviral prostaglandins in human cells infected with human immunodeficiency virus type 1.

Cyclopentenone prostaglandins inhibit the replication of several DNA and RNA viruses, including retroviruses. The antiviral activity has been associated with the induction of a 70-kDa heat-shock protein (HSP70), via activation of the heat-shock transcription factor (HSF) in infected cells. In the present study we investigated the effect of prostaglandin A1 (PGA1) on the regulation of HSP70 gene expression as well as on viral RNA and protein synthesis in CEM-SS cells during acute infection with human immunodeficiency virus type 1 (HIV-1). We report that HIV-1 infection does not alter HSF activation by PGA1, whereas it causes an increase in intracellular HSP70 mRNA levels, as a result of enhanced HSP70 mRNA stability. We also show that, as reported in studies of different virus/host cell models, PGA1 inhibits HIV-1 replication by acting at multiple levels during HIV-1 infection. In addition to the previously reported block of HIV-1 mRNA transcription, PGA1 was also found to inhibit viral protein synthesis. These results, together with the fact that prostaglandins are used clinically in the treatment of several diseases, open new perspectives in the search for novel antiretroviral drugs.

Antiviral Agents↗

PubMed1998

Characterization of Toscana virus-defective interfering particles generated in vivo.

Toscana (TOS) virus stocks strongly interfering with standard virus replication were obtained by sequential passages of virus in suckling mouse brain. Characterization of viral RNAs in these stocks showed the presence of a heterogeneous population of defective RNA molecules derived from the L genomic segment, in both nucleocapsid (NC) and messenger RNAs, suggesting that these molecules could be replicated, assembled, and transcribed. Subgenomic RNAs from the L segment but not from the S or M segments were found in cells infected with these stocks. Defective RNA molecules interfered with virus replication and retained 5' and 3' genomic termini. Nucleotide sequence analysis of some cloned defective interfering (DI) RNAs revealed they contained one or more internal deletions reducing their length to 7-13% of the full-length L segment. An identical sequence motif, of variable length, was found at both terminal sites of the RNA junction on standard L sequences. This motif was retained only in one copy in the subgenomic RNA. These results are consistent with the generation of TOS virus DI particles in vivo and suggest that the defective genomic RNAs could be generated by polymerase jumping from a sequence to an identical one spatially closed because of the RNA structure.

Animals↗

PubMed1998

In vivo identification of nuclear factors interacting with the conserved elements of box C/D small nucleolar RNAs.

The U16 small nucleolar RNA (snoRNA) is encoded by the third intron of the L1 (L4, according to the novel nomenclature) ribosomal protein gene of Xenopus laevis and originates from processing of the pre-mRNA in which it resides. The U16 snoRNA belongs to the box C/D snoRNA family, whose members are known to assemble in ribonucleoprotein particles (snoRNPs) containing the protein fibrillarin. We have utilized U16 snoRNA in order to characterize the factors that interact with the conserved elements common to the other members of the box C/D class. In this study, we have analyzed the in vivo assembly of U16 snoRNP particles in X. laevis oocytes and identified the proteins which interact with the RNA by label transfer after UV cross-linking. This analysis revealed two proteins, of 40- and 68-kDa apparent molecular size, which require intact boxes C and D together with the conserved 5',3'-terminal stem for binding. Immunoprecipitation experiments showed that the p40 protein corresponds to fibrillarin, indicating that this protein is intimately associated with the RNA. We propose that fibrillarin and p68 represent the RNA-binding factors common to box C/D snoRNPs and that both proteins are essential for the assembly of snoRNP particles and the stabilization of the snoRNA.

Animals↗

PubMed1998

Triphasic waves associated with acute naproxen overdose: a case report.

Triphasic waves (TWs) can be recorded on EEG in the course of several metabolic disorders, mainly hepatic encephalopathy. A case of acute encephalopathy due to naproxen intoxication is reported, in the course of which diffuse, bilateral and symmetrical TWs were recorded. Biochemical mechanisms that might determine both a complex encephalopathy and TWs are discussed.

Acidosis, Lactic↗

PubMed1997

Completion of molecular characterization of Toscana phlebovirus genome: nucleotide sequence, coding strategy of M genomic segment and its amino acid sequence comparison to other phleboviruses.

The M RNA segment of Toscana (TOS) phlebovirus was cloned and the complete nucleotide sequence determined. The M RNA segment is 4215 nucleotides in length, and it contains a single major open reading frame (ORF) in the viral-complementary sequence, between nucleotides 18 and 4034, which can encode for a polyprotein of 1339 amino acids (Mr 149 kDa). The viral segment is expressed via a unique mRNA containing 10-14 non-templated nucleotides at the 5' end and it is truncated at the 3' end by about 140 nucleotides in a purine-rich region. In M predicted amino acid sequences, several hydrophobic regions have been identified. They could function as a signal sequence or a transmembrane region for the different proteins. Comparison of the deduced amino acid sequence of M precursor product revealed 38, 36, and 25% identity and 58, 56, and 47% similarity with those of Rift Valley fever (RVF), Punta Toro (PT) and Unkuniemi (UUK) viruses, respectively. Residues conserved among the proteins are mainly located at the COOH-portion of the precursor, while the major divergence is in the NSm coding regions. Based on sequence comparison and similarity of hydropathic pattern of TOS M segment with other phleboviruses the N-termini of TOS GN and GC glycoproteins were placed at residues 297 and 936 of the precursor.

Amino Acid Sequence↗

PubMed1997

Organization of the M genomic segment of Toscana phlebovirus.

The nucleotide sequence of the Toscana (TOS) virus M RNA segment contains a single major open reading frame in the viral-complementary sequence, which can encode a polyprotein of 1339 amino acids. To map the TOS M segment product(s), different regions of the putative M polypeptide were expressed as glutathione S-transferase fusion proteins, which were purified and inoculated into mice to produce hyperimmune sera. By Western blot analysis, a protein of approximately 30 kDa and two glycoproteins, G1 and G2, with the same molecular mass (approximately 65 kDa) were identified in TOS virus-infected cells. The 30 kDa protein, which reacted with antibodies raised to the NH2-terminal, was found to be a non-structural protein (designated NSm). By immunoprecipitation analysis of TOS virus-infected cell lysates, both treated or untreated with tunicamycin, the relative positions of glycoproteins G1 and G2 were determined. The gene order, with respect to the genomic M RNA, was found to be 3' NSm-G1 -G2 5'

Animals↗

PubMed1997

Preliminary clinical experience with intraoperative stereotactic ultrasound imaging.

Neurosurgery guided by intraoperative ultrasound imaging is presented. The method is based on a stereotactic handfree ultrasound imaging device, designed to monitor cerebral shifts and lesion volume modifications during surgery. Preoperative CT and MR, acquired within a reference system, merge with ultrasound images stereotactically obtained by means of a lockable articulated encoded support. Landmarks from the lesion and surrounding structures are identified prior to opening of the dura and used during surgery to monitor volume changes.

Brain↗

PubMed1997

Radiosurgery for cerebral AVMs in children and adolescents: the neurobehavioral outcome.

Eight patients, ranging in age from 9 to 18 years, were treated for arteriovenous malformations using gamma knife radiosurgery and were evaluated an average of 6 years after treatment to record potential effects of radiosurgery on cognitive and neuropsychological performance. Tests for general intelligence, nonverbal intelligence, memory and its components, and attention performance were administered to patients and compared with test results of age-matched siblings or first cousins. No statistically significant difference was found between the performance of patients and controls in any of the tests administered. Additionally, a specially designed questionnaire completed by the patients, their parents, and their teachers revealed that the patients' emotional and relational behavior was stable and unchanged after treatment. No correlation was found between the neurocognitive test performance and the lesion volumes irradiated, but the lesion site was found to contribute to the type of deficit recorded after treatment. The less invasive nature of the radiosurgical approach, combined with the brevity or absence of hospitalization, presumably contributed to the patients successful physical, mental, and emotional recovery.

Adolescent↗

PubMed1997

[The study on the effect of prostaglandins A1 on the replication of human immunodeficiency virus type 1 (HIV-1) in vitro].

We observed the effect of prostaglandins A1 (PGA1) on the replication of HIV-1 by Northern-blot method in the CEM-ss cells which had been infected with HIV-1. The results showed that the RNA levels of HIV-1 in infected cells treated with PGA1 was lower than that of controls in low MOI 72-96 hours postinfection. The RNA of HIV-1 was dramatically reduced in infected CEM-ss cells when PGA1 was given 24 hours postinfection. The inhibition effect of PGA1 lasted for 9 days when PGA1 was given constantly.

Blotting, Northern↗

PubMed1996

Inhibition of HIV-1 replication by cyclopentenone prostaglandins in acutely infected human cells. Evidence for a transcriptional block.

Cyclopentenone prostaglandins (PGs) inhibit virus replication in several DNA and RNA virus models, in vitro and in vivo. In the present report we demonstrate that the cyclopentenone prostaglandins PGA(1) and PGJ(2) at nontoxic concentrations can dramatically suppress HIV-1 replication during acute infection in CEM-SS cells. PGs did not affect HIV-1 adsorption, penetration, reverse transcriptase activity nor viral DNA accumulation in HIV-1 infected cells. A dramatic reduction in HIV-1 mRNA levels was detected up to 48-72 h after infection (p.i.) in PG-treated cells, and HIV-1 protein synthesis was greatly reduced by a single PG-treatment up to 96 h p.i. Repeated PGA(1)-treatments were effective in protecting CEM-SS cells by the cytopathic effect of the virus, and in dramatically reducing HIV-1 RNA levels up to 7 d after infection. The antiviral effect was not mediated by alterations in the expression of alpha-, beta-, or gamma-interferon,TNFalpha, TNFbeta, IL6, and IL10 in HIV-infected CEM-SS cells. The fact that prostaglandins are used clinically in the treatment of several diseases, suggests a potential use of cyclopentenone PGs in the treatment of HIV-infection.

Antiviral Agents↗

PubMed1996

Spindle coma and alternating pattern in the course of measles encephalitis.

Acute disseminated encephalomyelitis (ADEM) is a well known complication of measles infection. Electroencephalographic abnormalities may occur frequently, in the form of moderate to severe diffuse high voltage theta-delta activity. We report a case of measles encephalitis with rapid benign outcome, that showed peculiar EEG features both of a "spindle coma" pattern and of an "alternating pattern." Possible physiological explanations of the EEG findings are discussed.

Adolescent↗

PubMed1995

Robot-assisted microscope for neurosurgery.

We describe the implementation of a robotic arm connected to a neurosurgical operative microscope. A force feedback sensor drives the motors of the arm in response to the positioning of the microscope by the surgeon. Computer graphic techniques allow tracking of the current position of the microscope within the volumetric reconstruction of the brain. The integration of the prototype into the neurosurgical operating room is currently being evaluated. Preliminary comments on this experimental phase are offered.

Angiography, Digital Subtraction↗

PubMed1994

A computer assisted toolholder to guide surgery in stereotactic space.

A computer assisted toolholder, integrated with an anatomical graphic 3-D rendering programme, is presented. Stereotactic neuroanatomical images are acquired, and the same reference system is employed to represent the position of the toolholder on the monitor. The surgeon can check the orientation of different approach trajectories, moving the toolholder in a situation of virtual reality. Angular values expressed by high precision encoders on the five joints of the toolholder modify "on line" the representation of the configuration of the toolholder within the three dimensional representation of the patient's anatomy.

Artificial Intelligence↗

PubMed1994

Intelligence outcome in children with shunted hydrocephalus of different etiology.

Children with shunted hydrocephalus of differing etiologies were assessed. There was a more selective loss of non-verbal than of verbal intelligence. The verbal and visuo-perceptual abilities were affected by different sets of variables. Variables related to the hydrocephalus had no effects, while associated supratentorial malformations significantly affected non-verbal functions.

Adolescent↗