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V Rossi

Publications and source records attributed to V Rossi.

At least 73 records · Page 4Linked to original sources
PubMed1996

A (15;17) translocation not associated with acute promyelocytic leukaemia.

We report a woman with acute myeloid leukaemia (AML) type M2 according to FAB classification, showing a t(15;17) apparently identical to that of acute promyelocytic leukaemia (APL) on conventional cytogenetic analysis. Fluorescence in situ hybridization (FISH) using cosmidic probes specific for RAR alpha and PML, regions did not show a fusion signal as in APL. The breakpoints were assigned to 15q24.3 and 17q21.1. Detailed molecular analyses did not reveal any involvement of RAR alpha and PML genes. The patient was resistant to several front-line AMI treatments and to all-trans retinoic acid (ATRA). These findings reinforce FISH and RT-PCR as useful tools for the characterization of a t(15;17) as the translocation specifically associated with APL.

Adult↗
PubMed1996

Alternative approaches to the prognostic stratification of mild to moderate primary vesicoureteral reflux in children.

PURPOSE: We compared the prognostic stratification of primary vesicoureteral reflux by performing staging voiding cystourethrography in all children with a urinary tract infection or only in those with renal scarring on 99mtechnetium-dimercapto-succinic acid (DMSA) scintigraphy. MATERIALS AND METHODS: Staging voiding cystourethrography and DMSA scintigraphy were performed in 105 children with a urinary tract infection and reflux persistence was assessed by radionuclide cystography after a 2-year followup. RESULTS: Staging voiding cystourethrography revealed no reflux in 51 children (DMSA positive in 3), grades I to II reflux in 21 (DMSA positive in 6) and grade III reflux in 33 (DMSA positive in 19). On followup radionuclide cystography no new reflux was detected, and it was no longer demonstrated in 23 children (8 with grade III and 15 with grades I to II reflux). The finding of grade III reflux on staging voiding cystourethrography had a 76% positive and a 92% negative value for predicting persistent reflux with an 87% predictive accuracy. Limiting the evaluation of voiding cystourethrography data to the 28 children with a positive DMSA scan the combination of renal scarring and grade III reflux had an 84% positive and an 83% negative predictive value with 83% accuracy. This approach would have prevented 77 children from having to undergo voiding cystourethrography. CONCLUSIONS: Performance of staging voiding cystourethrography exclusively in children with renal scarring on a DMSA scan resulted in predictive accuracy that was close to what was achieved by performing voiding cystourethrography in all children with a urinary tract infection. To be able to limit cystourethrography to a select population could prove to be cost-effective.

Case-Control Studies↗
PubMed1995

Structure of the catalytic region of human complement protease C1s: study by chemical cross-linking and three-dimensional homology modeling.

C1s is a multidomain serine protease that is responsible for the enzymatic activity of C1, the first component of the classical pathway of complement. Its catalytic region (gamma-B) comprises two contiguous complement control protein (CCP) modules, IV and V (about 60 residues each), a 15-residue intermediary segment, and the B chain (251 residues), which is the serine protease domain. With a view to identify domain-domain interactions within this region, the gamma-B fragment of C1s, obtained by limited proteolysis with plasmin, was chemically cross-linked with the water-soluble carbodiimide 1-ethyl-3-[3-(dimethylamino)propyl]carbodiimide; then cross-linked peptides were isolated after CNBr cleavage and thermolytic digestion. N-Terminal sequence and mass spectrometry analyses allowed us to identify two cross-links between Lys 405 of module V and Glu 672 of the B chain and between Glu 418 of the intermediary segment and Lys 608 of the B chain. Three-dimensional modeling of the CCP modules IV and V and of the catalytic B chain was also carried out on the basis of their respective homology with the 16th and 5th CCP modules of complement factor H and type I serine proteases. The information provided by both the chemical cross-linking studies and the homology modeling enabled us to construct a three-dimensional model for the assembly of the C-terminal part of the gamma-B region, comprising module V, the intermediary segment, and the B chain. This model shows that module V interacts with the serine protease B chain on the side opposite to both the activation site and the catalytic site. Functional implications of this interaction are discussed in terms of the possible role of module V in the specific recognition and positioning of C4, one of the two substrates of C1s.

Amino Acid Sequence↗
PubMed1995

Analysis of the N-linked oligosaccharides of human C1s using electrospray ionisation mass spectrometry.

Information on the structures of the oligosaccharides linked to Asn residues 159 and 391 of the human complement protease C1s was obtained using mass spectrometric and monosaccharide analyses. Asn159 is linked to a complex-type biantennary, bisialylated oligosaccharide NeuAc2 Gal2 GlcNAc4 Man3 (molecular mass = 2206 +/- 1). Asn391 is occupied by either a biantennary, bisialylated oligosaccharide, or a triantennary, trisialylated species NeuAc3 Gal3 GlcNAc5 Man3 (molecular mass = 2861 +/- 1), or a fucosylated triatennary, trisialylated species NeuAc3 Gal3 GlcNAc5 Man3 Fuc1 (molecular mass = 3007 +/- 1), in relative proportions of approximately 1:1:1. The carbohydrate heterogeneity at Asn391 gives rise to three major types of C1s molecules of molecular masses 79,318 +/- 8 (A), 79,971 +/- 8 (B), and 80,131 +/- 8 (C), with an average mass of 79,807 +/- 8. A minor modification, yielding an extra mass of 132 +/- 2, is also detected within positions 1-153.

Asparagine↗
PubMed1995

Molecular analysis of opaque-2 alleles from Zea mays L. reveals the nature of mutational events and the presence of a hypervariable region in the 5' part of the gene.

Ten recessive Opaque-2 (O2) alleles of independent origin were characterized at the molecular level. The results revealed a high level of polymorphism at the O2 locus. In addition, our data suggest the possible cause for the recessive character of some of the alleles investigated, and allow us to infer some conclusions concerning the degree of relationship between the o2 mutations. Comparison of genomic sequences spanning the first exon and obtained from a series of wild-type and recessive alleles revealed the presence of a hypervariable region, involving different dipeptides, in the N-terminal part of the O2 protein.

Alleles↗
PubMed1995

Technetium-99m-sestamibi imaging with nitrate infusion to detect viable hibernating myocardium and predict postrevascularization recovery.

UNLABELLED: We tested the relationship of nitrate-induced changes in 99mTc-sestamibi perfusion tomography and first-pass radionuclide angiocardiography (FPRNA) with postrevascularization functional recovery of asynergic territories. METHODS: Twenty-eight patients, all with prior infarction and left ventricular dysfunction, underwent two 99mTc-sestamibi rest studies: one under baseline conditions and the other with nitrate infusion. The baseline study was repeated after revascularization. Changes in global and regional perfusion and ventricular function were evaluated by perfusion tomography and FPRNA. Hibermating myocardium was identified by functional recovery in postrevascularization FPRNA. RESULTS: Eleven patients and 31 segments in 19 coronary territories had functional recovery. Nitrate-induced FPRNA changes showed poor agreement with postrevascularization modifications: kappa = 0.24, ns, for the global and kappa = 0.32, p < 0.01 for regional function. The agreement between nitrate-induced and postrevascularization perfusion changes was good both considering the patients (k = 0.57, p < 0.01) and the abnormal coronary territories (k = 0.63, p < 0.0005). The agreement of nitrate-induced perfusion changes with postrevascularization functional outcome was excellent on a patient (k = 1, p < 0.0005), and coronary territory basis (k = 0.82, p < 0.0005). Conversely, the agreement between nitrate and postrevascularization FPRNA was poor: k = 0.18, ns. CONCLUSION: These data suggest that the nitrate-induced changes in 99mTc-sestamibi perfusion imaging are useful to detect hibernating myocardium which recovers its function after revascularization.

Angina Pectoris↗
PubMed1995

Nitrate versus rest myocardial scintigraphy with technetium 99m-sestamibi: relationship of tracer uptake to regional left ventricular function and its significance in the detection of viable hibernating myocardium.

Rest technetium 99m-sestamibi uptake may underestimate myocardial viability in asynergic territories. Because nitrate administration was reported to improve thallium 201 uptake in perfusion defects, this study aimed to test the influence of nitrates on 99mTc-sestamibi uptake and on the tracer capability to recognize viable tissue in asynergic segments. In 23 patients with prior infarction and left ventricular dysfunction, regional wall motion was assessed by echocardiography before and after revascularization (13 segments/patient). Group 1 included 97 normokinetic; group 2, 97 hypokinetic; and group 3, 105 akynetic or dyskinetic segments; group 3 was divided into group 3A (72 segments unchanged after revascularization) and group 3B (33 segments with functional recovery). 99mTc-sestamibi uptake was graded using a scoring scheme in the same 13 segments both at rest and, on a separate day, injecting the tracer during isosorbide dinitrate infusion (ISDN). At rest, the mean 99mTc-sestamibi uptake decreased significantly from group 1 through group 3. With ISDN, the mean 99mTc-sestamibi uptake increased in all groups compared with rest, but the increase was significant only in groups 2 and 3, and within the latter, only in group 3B. Thus, with ISDN group 3B was no longer different from group 2. Only 6% of group 3A segments showed an improved uptake with ISDN, versus 33% of group 3B (P < .00005). At rest only 14 of 33 segments of group 3B showed a normal or slightly reduced uptake, whereas these were 25 of 33 with ISDN (P < .02). In conclusion, the acute administration of ISDN increases the uptake of 99mTc-sestamibi mainly in those asynergic territories that show postrevascularization functional recovery. Therefore, ISDN 99mTc-sestamibi imaging might improve the tracer capability to detect viable hibernating myocardium.

Angioplasty, Balloon, Coronary↗
PubMed1995

[Abdominal carcinoid: various locations and clinical course].

Carcinoid tumours are rare neoplasms and their behaviour seems to change with the localization; in fact, appendiceal and rectal carcinoids show a better long-term survival than the more aggressive ileal and colonic analogues. The Authors report their experience in the surgical treatment of 13 G.I. carcinoid neoplasms, in which the clinical course was sometimes unpredictable suggesting there is much to discover about the behaviour of these particular tumours.

Adolescent↗
PubMed1995

[Hypothyroidism associated with retrobulbar optic neuritis. A clinical case].

The authors have described a hypothyroidism clinic event with both non-specific symptoms and retrobulbar neuritis. They conclude that the above-mentioned pathology is somewhat insidious since, affecting the whole body, it can arise with non-specific symptoms thus averting towards a wrong diagnosis.

Diagnosis, Differential↗
PubMed1994

Suppression of juvenile chronic myelogenous leukemia colony growth by interleukin-1 receptor antagonist.

Bone marrow (BM) and peripheral blood (PB) cells from patients with juvenile chronic myelogenous leukemia (JCML) exhibit spontaneous in vitro proliferation. Several cytokines including granulocyte-macrophage colony-stimulating factor (GM-CSF), interleukin-1 beta (IL-1 beta), and tumor necrosis factor alpha (TNF alpha) have been implicated in supporting the growth of leukemic monocyte-macrophage colonies either by autocrine or paracrine pathways. In seven untreated JCML patients, we investigated the role of IL-1 in the spontaneous growth of these cells by specifically blocking IL-1 receptors. The IL-1 receptor antagonist (IL-1 Ra) was added to the clonogenic assays, and in each case significant (mean = 63%, range = 35% to 82%) inhibition of spontaneous proliferation was observed. Uncultured circulating cells from PB or BM of four out of five patients expressed IL-1 beta-specific mRNA and secreted the protein into the culture supernatants. Moreover, by means of reverse transcriptase-polymerase chain reaction (RT-PCR), we demonstrated that most of the spontaneously growing leukemic colony-forming unit cells (CFU-C) obtained from BM cells of two patients were positive for the presence of the IL-1 beta-specific mRNA. Despite the presence of a measurable amount of GM-CSF in JCML cell culture supernatants, GM-CSF-specific mRNA in CFU-C cells of four cases was not detected by RT-PCR. These data further support a central role for IL-1 beta in the pathogenesis of JCML and suggest that the use of IL-1 Ra could represent a novel therapeutic strategy against this disorder.

Adult↗
PubMed1994

Structural and functional analysis of an Opaque-2-related gene from sorghum.

The Opaque-2 (O2) gene from maize encodes a transcriptional activator of the b-ZIP class. We have isolated and characterized a gene from sorghum, related in sequence to the O2 gene from maize. A single copy of the gene is present in sorghum. Both genomic and cDNA sequences of the O2-related sorghum gene were determined. The sequence is highly homologous to maize O2 both in the promoter and in the coding region. The most closely related sequences contain the b-ZIP domain with only 11 amino acid substitutions in a total of 122 residues. In transient expression assays, the sorghum O2-related coding sequence, expressed from a CaMV 35S promoter, activates expression from the maize b-32 promoter as effectively as that obtained with the maize O2 sequence.

Amino Acid Sequence↗
PubMed1994

Structural organisation of microsatellite families in the Leishmania genome and polymorphisms at two (CA)n loci.

In the present study, we have analysed the frequency and distribution of several microsatellite DNAs [(CA)n, (GGT)n and (GCA)n] in the genome of Leishmania. Hybridisation analysis on the molecular karyotypes of different Leishmania strains showed the presence of these three microsatellites on all chromosomes of the parasite. The number of microsatellite clusters appeared grossly similar among strains from different Old World complexes. However, these three microsatellite families showed an uneven distribution among heterologous chromosomes of the same strain. Moreover, restriction analysis of chromosome I in various strains of Leishmania infantum showed a strong clustering of these microsatellites in the same chromosomal region. A partial genomic library was screened with a (CA)n probe, and 21 positive clones were isolated. The sequencing of these clones confirmed the association of various microsatellites such as (CA)n, (CT)n, and (GCA)n. Finally, specific polymerase chain reaction amplification of two cloned (CA)n loci demonstrated allelic size polymorphisms among strains within L. infantum and Leishmania donovani. Most of the 34 strains analysed were found to be monoallelic, while two alleles were found in a small number of strains. The interest of these sequences for studies on ploidy and population genetics of the parasite is discussed.

Animals↗
PubMed1994

Monitoring of treatment outcome in acute promyelocytic leukemia by RT-PCR.

A rearrangement between the PML and RAR-alpha genes underlies the acute promyelocytic leukemia (APL)-specific t(15;17) translocation, leading to the production of a chimeric mRNA. Recent development of a reverse-transcription polymerase chain reaction (RT-PCR) assay for the PML/RAR-alpha hybrid has proven useful for rapid diagnosis and monitoring of minimal residual disease (MRD) in APL patients. Preliminary studies in which the prognostic significance of RT-PCR was evaluated indicate that this test may identify patients at high risk of relapse.

Hematologic Diseases↗
PubMed1994

Monitoring of treatment outcome in acute promyelocytic leukemia by RT-PCR.

A rearrangement between the PML and RAR-alpha genes underlies the acute promyelocytic leukemia (APL)-specific t(15;17) translocation, leading to the production of a chimeric mRNA. Recent development of a reverse-transcription polymerase chain reaction (RT-PCR) assay for the PML/RAR-alpha hybrid has proven useful for rapid diagnosis and monitoring of minimal residual disease (MRD) in APL patients. Preliminary studies in which the prognostic significance of RT-PCR was evaluated indicate that this test may identify patients at high risk of relapse.

Chromosomes, Human, Pair 15↗
PubMed1994

[Cardiomyopathy in hypothyroidism. Description of a clinical case].

The authors describe a case of hypothyroidism the only symptom of which at presentation was myopathy. Hypothyroidism was diagnosed only after abnormalities of thyroid hormones, thyroid scanning, and antithyroglobulin and antimicrosome antibodies were found. The authors conclude that the diagnosis of hypothyroidism is very difficult in the absence of the typical signs, such as drowsiness, edema, dry skin, hoarse voice, alopecia, etc.

Adult↗
PubMed1993

Detection of ALL-1/AF4 fusion transcript by reverse transcription-polymerase chain reaction for diagnosis and monitoring of acute leukemias with the t(4;11) translocation.

The chromosomal breakpoints of t(4;11) translocation of acute lymphoblastic leukemia (ALL) have been recently identified at molecular level and shown to involve the AF4 (FEL) gene on chromosome 4 and the ALL-1 (MLL, Hrx) gene on chromosome 11. The ALL-1/AF4 fusion gene is transcribed into a chimeric mRNA. Using primer sets derived from ALL-1 and AF4 cDNAs by reverse transcription-polymerase chain reaction (RT-PCR), we were able to amplify the breakpoint sites of the fusion transcript of all 15 ALL cases with karyotypic or molecular evidence of the t(4;11). DNA fragments of different size were obtained as the consequence of different breakpoints on chromosome 11 and the presence of alternative splicing of ALL-1 exon 8. The feasibility of monitoring the residual cells carrying the t(4;11) in 2 ALL patients with different clinical outcome was evaluated. Overall, the presented results provide evidence that RT-PCR can be used as a rapid method for detecting this chromosomal abnormality and following the patient's response to therapy.

Adolescent↗