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Biomedical subjects

A Serra

Publications and source records attributed to A Serra.

At least 91 records · Page 5Linked to original sources
PubMed1998

[Critical review of renal transplantation data from the Piedmontese Regional Dialysis and Transplantation Registry].

On 31/12/1995 a total of 1,128 Piedmontese uremic patients had undergone kidney transplantation, with 65% of operations performed by the Regional Reference Centre and 35% by extra-regional centres. Waiting time for dialysis was less than 5 years in over half of the patients most of whom were aged between 40 and 60 years old. In overall terms, the patient survival rate was 94%, 87%, 75% at 24, 60, 120 months respectively, with a statistically significant improvement when the curve was evaluated in the patient-pool treated with cyclosporine (84% versus 87% at 7 years). Organ survival was 76% at 21 years and 42% at 10 years, and results were again improved by the use of cyclosporine. Pathologies affecting the transplanted organ represent the main cause of morbidity; drop-out during dialysis is caused above all by immunological diseases. Infectious pathologies were responsible for the majority of deaths in this population.

Adolescent↗
PubMed1998

[Primary MALT-type lymphoma of the breast].

A 47 year old woman with a MALT lymphoma affecting the breast exclusively is reported. Complete response was achieved after CHOP chemotherapy but three years later a relapse was observed. Second-line chemotherapy (CNOP) and local radiotherapy were administered, and a second remission was obtained lasting for 1 year at last follow-up. A bibliographic search of MALT lymphomas of the breast showed that most such cases correspond to localized forms (stage I-II) and that from the radiologic point of view nodular lesions are almost the rule, although in the present case diffuse involvement was observed. MALT lymphomas of the breast tend to remain localized, and to relapse locally, and these facts appear as independent of the treatment applied (surgery, radiotherapy, chemotherapy or any combination).

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1998

Expression of cell cycle regulatory genes in chronic myelogenous leukemia.

BACKGROUND AND OBJECTIVE: Cell cycle regulatory genes are frequently altered in a variety of malignancies. The structure and pattern of expression of eight genes involved in cell division cycle control were studied in leukemic cell samples prepared from bone marrow of patients affected by chronic myelogenous leukemia. DESIGN AND METHODS: Ten cell preparations were obtained from patients in the chronic phase, five from those in myeloid blast crisis and five from those in the lymphoid acute phase. Moreover, bone marrow CD34+ cells, purified from healthy subjects and patients with chronic myelogenous leukemia (both during chronic and acute phases), were analyzed. The investigated genes were RB1, p53 and six cyclin-dependent kinase inhibitor genes (p15INK4B, p16INK4A, p18INK4C, p21WAF1/CIP1, p27Kip1, p57Kip2). RESULTS: We found that none of these genes is structurally altered in either the chronic or acute phases, with the single exception of the p16INK4A gene, which was homozygously deleted in 1 case of lymphoid evolution. p57Kip2 expression is down-regulated during the evolution towards the blast crisis both in malignant and CD34+ cells. In addition, a significant up-regulation of p15INK4B gene expression is observable during the development of the acute phase of malignancy. INTERPRETATIONS AND CONCLUSIONS: The transcriptional modulation of some cyclin-dependent kinase inhibitors might contribute to the fatal blast crisis of chronic myelogenous leukemia.

Blast Crisis↗
PubMed1997

Differential effect of a low-molecular-weight heparin (dalteparin) and unfractionated heparin on platelet interaction with the subendothelium under flow conditions.

Effects of heparins on platelet function are controversial, but perfusion studies, that simulate physiological conditions, might help to explain their clinical behaviour. We used a perfusion system to test the effect unfractionated heparin and a low-molecular-weight heparin (dalteparin, Fragmin) on platelet adhesion promoted by a damaged vascular surface. Normal blood samples containing increasing concentrations of unfractionated heparin and dalteparin were perfused through annular chambers containing enzymatically denuded rabbit aorta segments (5 min at 800 sec-1). Segments were evaluated morphometrically measuring the total surface covered by platelets and by large aggregates (thrombi). Unfractionated heparin inhibited platelet interaction with subendothelium in a lesser extent than dalteparin in both covered surface and thrombi (p < 0.01). At heparin doses that caused maximal inhibition covered surface was 10.0% +/- 3.1% with dalteparin and 18.3% +/- 4.2% with unfractionated heparin, and thrombi were 5.6% +/- 3.2% and 12.3% +/- 3.0%, respectively. These results may collaborate to explain some differences observed in the clinical results obtained with unfractionated heparin and with dalteparin.

Animals↗
PubMed1997

Partial 9p monosomy in a girl with a tdic(9p23;13p11) translocation, minor anomalies, obesity, and mental retardation.

We report on a case with a partial monosomy for the regions 9p23 --> pter and 13p11 --> pter as a result of a de novo translocation (9p23;13p11). The patient, a 16-year-old girl, has mental deficiency, obesity, and minor anomalies, including trigonocephaly, hypertelorism and a short, broad neck. Cytogenetic and microsatellite marker analysis allowed us to assign the breakpoint to the chromosomal region 9p23, flanked by the markers D9S144 and D9S157. In an attempt to establish a phenotype-genotype correlation, the clinical manifestations present in our patient are compared to those with partial 9p monosomy and breakpoint in p23, referred to in the literature.

Abnormalities, Multiple↗
PubMed1997

Unusual locations of osteoarticular tuberculosis.

Tuberculosis continues to occur frequently in some underdeveloped regions. Bone and joint tuberculosis is less common than the pulmonary form. Fourteen cases of bone and joint tuberculosis in unusual locations are presented. Tuberculostatic treatment and surgical approach were associated in all the patients. In 6 cases an arthrodesis of the affected joint was carried out. A surgical debridement was done in 6 patients and a needle biopsy in 2 patients in order to obtain samples for pathology and bacteriology. Twelve of the 14 patients recovered. One patient who was affected by atlanto-axial tuberculosis died within the immediate postoperative period. A second one affected by the acquired immunodefiency syndrome died 4 months after surgery.

Adult↗
PubMed1997

Disruption of the Kamin blocking effect in schizophrenia and in normal subjects following amphetamine.

The Kamin blocking effect (KBE) is an established animal learning paradigm measuring selective processing, in which reduced blocking reflects allocation of greater processing resources to non-relevant information. Two KBE tasks are described below. Results from studies using the first (between-subjects) task indicate that KBE is abolished in acute schizophrenics with positive psychotic symptoms. It is also abolished in the relatives of schizophrenic subjects, although interpretation of this finding is hampered by poor performance of subjects in the control condition. The second (within-subjects) task indicated abolition of KBE in schizophrenic patients with positive psychotic symptoms. Administration of acute amphetamine to normal human subjects did not significantly disrupt performance on the first task. Whilst for the second task, although blocking was limited to placebo subjects, overall pre-exposure effects are not sufficiently strong to indicate specific drug effects.

Amphetamine↗
PubMed1997

[Registry of activities of the Hemodynamics and Interventional Cardiology Section in the year 1996].

The results of the Spanish Registry of Hemodynamic and Interventional Cardiology in 1996 are presented. The Registry collects the activity of 81 centers which constitutes all of the cardiac catheterization laboratories in Spain. The main activity was adult cardiac catheterization in 73 centers and exclusively pediatric cardiac catheterization in 8. A total of 63,961 diagnostic catheterization procedures were performed, which represents a 10.7% increase compared to 1995. This was mainly due to the increase in coronary angiographies. Coronary interventions increased by 21.4%, for a total number of 15,009 procedures. The ratio of coronary interventions per million inhabitants was 375. Success rates of coronary interventions (94%) and complications (2.9%) were similar to those registered in preceding years. In the specific field of revascularization devices, there has been a sustained and spectacular increase in the use of intracoronary stents in the last 3 years. In 1996, coronary stents were employed in 7,104 cases (47.3% of all coronary revascularization procedures) and 8,873 prosthesis were implanted, increasing two-fold the activity in that field when compared to 1995. Stent implantation was elective in 58% cases, and the complication rate was very low (1% subacute closure; 1.8% myocardial infarction and 0.9% mortality). Directional coronary atherectomy decreased by 47% in the last year whereas rotational atherectomy increased by 10% despite a reduction in the number of centers performing this technique. As in previous years, a slight decrease in adult valvuloplasties was noted. Pediatric interventional procedures (607) increased by 30% compared to the 1995 Registry.

Adult↗
PubMed1997

Multigenetic lesions in infant acute leukaemias: correlations with ALL-1 gene status.

In this study we investigated the presence of structural lesions in the ALL-1, p53 and p16 (cyclin-dependent kinase 4 inhibitor) genes in leukaemic cells obtained from 22 patients with infant acute leukaemia (aged < 18 months). Of these, 18 cases were classified as acute lymphoblastic leukaemia (ALL) and four as acute myeloid leukaemia (AML). Tumour DNAs were analysed by a combination of Southern blot. polymerase chain reaction (PCR), single-strand conformation polymorphism (SSCP), and direct sequence analyses. The results showed ALL-1 gene rearrangements in 15/22 (68%) cases, p53 gene mutations in 5/22 (26%), and a homozygous deletion of p16 in a single T-ALL case. p53 and p16 alterations were all found in the group of patients with ALL-1 gene rearrangements. p53 mutations were more often associated with a myeloid phenotype (3/5). In summary, multiple molecular alterations were found in 6/15 (40%) infant acute leukaemias with ALL-1 rearrangements. As to the clinical course, patients with additional lesions had similar clinical outcome with respect to patients with ALL-1 gene rearrangement as the sole genetic aberration. This may support the hypothesis that ALL-1 alterations are genetic events per se sufficient to confer a fully malignant phenotype to the leukaemic clone.

Acute Disease↗
PubMed1997

The influence of diabetes mellitus on primary open angle glaucoma perimetry.

We have carried out a study into retinal sensitivity alterations in the course of primary open angle glaucoma to see if their appearance and evolution might be influenced by concomitant diabetes mellitus. The visual field examination (Perimeter Octopus 500 EZ, programme G1) indicated prevalent sensitivity defects in the superior hemifield, both in glaucoma only subjects and in those with diabetes as well. As to the inferior hemifield, a greater, statistically significant, retinal sensitivity defect was found in the inferior temporal quadrant of the left eye in the group of diabetics.

Diabetes Complications↗
PubMed1997

Molecular events in chronic myeloid leukemia progression.

Chronic myelogenous leukemia presents two distinct clinical phases: the chronic phase is characterised by a marked expansion of the myeloid compartment which still retains a normal differentiative capacity, whereas a differentiation block is the clinical hallmark of the acute transformation. The molecular mechanism underlying the CML progression are still poorly understood. The occurrence of additional molecular lesions, involving the p53, the RAS and the p16 genes may complement and fulfil the BCR/ABL transforming potential, finally leading to an acute leukemic phenotype. However, several lines of evidence suggest that also quantitative changes of the BCR/ABL transcript amounts could explain the progression of the leukemic phenotype in the BCR/ABL-positive hematologic malignancies.

Chromosome Mapping↗
PubMed1997

[Stents and de novo coronary lesions. Meta-analysis].

OBJECTIVES: The purpose of this investigation was to provide an overview of the effect of coronary artery stent and balloon angioplasty on major clinical outcomes and restenosis from 3 trials (BENESTENT, STRESS and START) comparing the two treatments in the novo lesions. METHODS: The trials included a total of 1,374 patients, 693 of whom were randomized to stent and 682 to conventional angioplasty. Relative risk, 95% confidence interval and p values were calculated for death, infarction and need for revascularization at 6 month follow-up. Restenosis was assessed by using the binary definition. RESULTS: The incidence of combined clinical outcomes was similar to the two treatment strategies (relative risk 0.96; 95% CI 0.64-1.45). However, the odds for needing a new revascularization procedure were reduced by 35% in patients treated with stents (relative risk 0.65; 95% CI 0.51-0.82; p < 0.001). Restenosis rates were 25% and 36.6% (stent vs angioplasty, respectively), which represents a reduction of 31% (relative risk 0.69; 95% CI 0.58-0.81; p > 0.0001). CONCLUSIONS: Compared with balloon angioplasty, coronary stents of de novo lesions in native coronary arteries decreases restenosis at 6 months. This translates into clinical benefit, as shown by a reduction in the number of new revascularization procedures.

Angioplasty, Balloon↗
PubMed1996

4-hydroxynonenal specifically inhibits c-myb but does not affect c-fos expressions in HL-60 cells.

4-Hydroxynonenal, an aldehyde produced from lipid peroxidation of cellular membranes, inhibits growth and induces differentiation of HL-60 human leukemic cell line. Since it is highly unstable in the culture medium, its effectiveness is increased when added repeatedly to the cell suspension. We have previously demonstrated that HNE inhibits c-myc but not N-ras expression in HL-60 cells. Here we investigate its effect on the expression of c-myb and c-fos, two early genes involved in the induction of myeloid and monocytic differentiation. Moreover, since c-fos is directly correlated with the intracellular level of cAMP, we also analysed the cAMP concentration after aldehyde treatment. HNE significantly inhibits c-myb expression during and after repeated treatments. A single administration of 1 microM HNE decreases c-myb mRNA at 1 hour whereas 10 microM HNE inhibits c-myb expression from 3 to 6 hours after treatment, and then the expression returns to the control level. By contrast, c-fos expression and intracellular cAMP concentration do not show any significant change after HNE treatments.

Aldehydes↗
PubMed1996

Persistence of tyrosine-phosphorylated FcepsilonRI in deactivated cells.

Engagement of the high affinity IgE receptor (FcepsilonRI) with a multimeric antigen leads to immediate tyrosine phosphorylation of its beta and gamma subunits, recruitment, and activation of the tyrosine kinase Syk, and later to cell degranulation. Monovalent hapten treatment reverses these events, resulting in receptor dephosphorylation and an abrupt arrest of cell degranulation. Thus far, it has been assumed that there is a direct linkage between receptor tyrosine phosphorylation, Syk activation and phosphorylation, and cell degranulation. However, we show here that when FcepsilonRI receptors are cross-linked for extended periods of time, hapten-mediated receptor dephosphorylation is delayed. These receptors, which remain tyrosine-phosphorylated despite the addition of hapten, are progressively targeted to a Triton X-100-insoluble fraction, suggesting their progressive association with the membrane skeleton. In contrast to FcepsilonRI receptors, hapten-induced Syk dephosphorylation and the consequent arrest of degranulation are not affected by prolonged cross-linking. Thus, some tyrosine-phosphorylated receptors persist in deactivated cells. We propose that, with time, some tyrosine-phosphorylated receptors become unaccessible to phosphatases and, in addition, unable to activate Syk. This inactive status of tyrosine-phosphorylated FcepsilonRI may be the result of membrane skeleton compartmentalization. However, another population of clustered receptors that includes the ones most recently formed is still immediately sensitive to hapten deactivation. This latter population is critical in maintaining Syk activity and cell degranulation. The shift from a transiently active state of phosphorylated receptors toward an inactive state could be a general mechanism of desensitization also utilized by other antigen receptors.

Adenosine Triphosphate↗
PubMed1996

Deletion in the peripherin/RDS gene in two unrelated Sardinian families with autosomal dominant butterfly-shaped macular dystrophy.

BACKGROUND: Autosomal dominant butterfly-shaped macular dystrophy is associated with different mutations of the peripherin/RDS gene. We studied the phenotype of two families with a novel large deletion in the peripherin/RDS gene. METHODS: Clinical study, fluorescein angiography, color vision testing, automatic perimetry, electrophysiologic studies, and DNA analysis were performed on all the members of the two families. RESULTS: Fundus examination in patients aged 30 to 60 years showed yellow deposits in the macula with a butterfly-shaped pattern. Central choroidal atrophy was present in the older patients only. Macular visual function tests (color vision and central visual field) were abnormal, and electro-oculograms were slightly subnormal in five individuals tested. Electroretinograms and results of dark adaptometry were normal. Linkage analysis with intragenic polymorphic markers and quantitative polymerase chain reaction showed heterozygosity for a large deletion that removed exons 2 and 3 of the peripherin/RDS gene in all affected members of two families. CONCLUSIONS: This deletion escaped detection by direct analysis of amplified exons and was identified by intragenic polymorphic markers analysis, resulting in loss of heterozygosity from affected parents to affected children, and by quantitative polymerase chain reaction. The delineation of the molecular defect associated with the disease in these two families allows us to verify the presence or absence of the disease in clinically unaffected members.

Adolescent↗
PubMed1996

Pulmonary function in Sardinian fire fighters.

Our study examined the respiratory function of 92 firemen whose main activity is fire fighting in forests and open country. Such fire fighting activities are to be considered a risk to the respiratory tract, taking into account studies already in the literature that have evaluated the nature and quantity of inhalable toxins present in activities of this kind. The control group was composed of 51 Carabinieri (policemen), who were asked to fill in a questionnaire about their work activities. Forced expiratory volume and flow, total lung capacity, respiratory volume, and the permeability of the alveolar-capillary barrier were measured. Firemen and Carabinieri (policemen) showed FVC rates higher than the European Community for Coal and Steel standards. The firemen showed a significant reduction in forced expiratory volume in 1 second (FEV1)[3.90 (0.50) vs. 4.04 (0.44); p < 0.05] and forced expiratory flow at 75% of forced vital capacity (FVC) (FEF75) [8.37 (4.11) vs. 8.38 (1.67) p < 0.05] and more markedly in the FEV 1/FVC relationship [80.07 (5.89) vs. 83.89 (1.67) p < 0.001] and in FEF50 [4.73 (1.34) vs. 5.54 (1.44) p < 0.01] and FEF25[1.58 (.47) vs. 1.99 (.69) p < 0.001]. There were no marked differences in air-blood exchanges. No correlation was found between respiratory function data and years of service or the number of fires extinguished during work experience.

Adult↗