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C Albo

Publications and source records attributed to C Albo.

At least 19 recordsLinked to original sources
PubMed2007

The results of consolidation with autologous stem-cell transplantation in patients with peripheral T-cell lymphoma (PTCL) in first complete remission: the Spanish Lymphoma and Autologous Transplantation Group experience.

BACKGROUND: Peripheral T-cell lymphoma (PTCL) is a heterogeneous group of aggressive lymphomas associated with poor prognosis with standard chemotherapy. Consolidation with autologous stem-cell transplantation (ASCT) may improve survival. We present 74 patients transplanted in first complete response (CR) from the Spanish Lymphoma and Autologous Transplantation Group cooperative group. PATIENTS AND METHODS: Median age was 46 years. Eighty-eight percent presented advanced (III-IV) Ann Arbor stage; 53% had B symptoms; 52% had high lactate dehydrogenase; 65% had two or three risk factors of the adjusted-International Prognostic Index; 58% presented a high Tumor score and in 14% more than two adverse factors of the Prognostic Index for peripheral T-cell lymphoma (PIT) were observed. RESULTS: With a median follow-up of 67 months from diagnosis, the 5-year overall survival (OS) was 68% and progression-free survival (PFS) reached 63%. The multivariate analysis showed that the only factor associated with a shorter OS and PFS was the presence of more than two risk factors from the PIT risk system. CONCLUSIONS: In a retrospective study with a prolonged follow-up, consolidation with ASCT in CR patients who had presented unfavorable prognostic factors at diagnosis substantially increased the OS and PFS when compared with conventional chemotherapy. The PIT risk system identified 14% of patients without benefit from ASCT consolidation. Thus, other innovative therapies are still necessary in certain cases.

Adolescent↗
PubMed2004

Efficacy and safety of femoral vascular access for peripheral blood stem cell (PBSC) collection.

Central venous catheters are frequently used in leukapheresis to provide high flow rates. The most common locations are the subclavian or jugular vein, but insertion-related complications and inadequate flow are frequent problems. Experience using femoral venous access is limited, because this has been discouraged due to the high incidence of infectious or thromboembolic complications. We evaluated the safety and efficacy of 108 short-term femoral venous dialysis catheters used for the collection of peripheral blood stem cells (PBSCs). All catheters were placed by a member of the dialysis unit, and they remained in situ for the days needed to reach the target number of CD34+cells. No prophylactic antibiotic or antithrombotic therapy was used. A total of 232 apheresis sessions was performed. The longest duration a catheter remained in situ was 5 days. Most of the patients finished the collection in one or two apheresis sessions. There were no thrombotic or infectious complications, and insertion-related complications or mechanical problems were minimal. Apheresis results were similar to those reported using subclavian or jugular venous access. The short-term use of femoral venous dialysis catheters appears safe and effective for PBSC collection, simplifying the procedure, improving patient comfort, and reducing cost.

Adolescent↗
PubMed2004

Autologous stem-cell transplantation in diffuse large B-cell non-Hodgkin's lymphoma not achieving complete response after induction chemotherapy: the GEL/TAMO experience.

BACKGROUND: Here we evaluate the results of high-dose chemotherapy and autologous stem-cell transplantation (HDC/ASCT) in 114 patients included in the GEL/TAMO registry between January 1990 and December 1999 with diffuse large B-cell lymphoma who failed to achieve complete remission (CR) with front-line conventional chemotherapy. PATIENTS AND METHODS: Sixty-eight per cent had a partial response (PR) and 32% failed to respond to front-line therapy. At transplant, 35% were chemoresistant and 29% had two to three adjusted International Prognostic Index (a-IPI) risk factors. RESULTS: After HDC/ASCT, 57 (54%) of 105 patients evaluable for response achieved a CR, 16 (15%) a PR and 32 (30%) failed. Nine patients were not assessed for response because of early death due to toxicity. With a median follow-up of 29 months for alive patients, the survival at 5 years is 43%, with a disease-free survival for complete responders of 63%. The lethal toxicity was 8%. Multivariate analysis revealed a-IPI and chemoresistance to be predicting factors. CONCLUSIONS: Our results show that one-third of patients who do not obtain a CR to front-line chemotherapy may be cured of their disease with HDC/ASCT. However, most chemoresistant patients pretransplant failed this therapy. For this population, as well as for those who presented with adverse factors of the a-IPI, pretransplant novel therapeutic modalities need to be tested.

Adolescent↗
PubMed2004

Methylene blue-photoinactivated plasma vs. fresh-frozen plasma as replacement fluid for plasma exchange in thrombotic thrombocytopenic purpura.

BACKGROUND AND OBJECTIVES: Plasma exchange with fresh-frozen plasma (FFP) is the treatment of choice in thrombotic thrombocytopenic purpura (TTP). Methylene blue-photoinactivated plasma (MBPIP) has been proposed as a safer alternative to FFP, but its effectiveness in the treatment of TTP is not well established. The purpose of this study was to investigate whether MBPIP is as effective as FFP in the treatment of TTP by plasma exchange. MATERIALS AND METHODS: A retrospective analysis was carried out of 56 TTP episodes, occurring between 1990 and 2003, which had been treated by plasma exchange. MBPIP was used for fluid replacement in 27 episodes and FFP in 29. The effect of plasma (MBPIP or FFP) on treatment outcomes was analysed by multivariate logistic regression. RESULTS: Compared to patients treated with FFP, those receiving MBPIP had an increased risk of dying from progressive TTP [adjusted odds ratio (OR) = 31; 95% confidence interval (CI): 1.2 to > 100], a greater number of recurrences while on plasma exchange therapy (OR = 4.6; 95% CI: 1.2-17), and a lower probability of attaining a sustained remission within 9 days of starting plasma exchange (OR = 5.2; 95% CI: 1.3-20). CONCLUSIONS: MBPIP seems to be less effective than FFP in the treatment of TTP. It is therefore prudent to avoid MBPIP until therapeutic equivalency to FFP has been established by randomized, controlled trials.

Adult↗
PubMed2004

[Quantification of longitudinal myocardial velocities by Doppler tissue imaging during dobutamine echocardiography].

Doppler tissue imaging has been suggested to be a valuable method for the diagnosis of myocardial ischaemia during dobutamine echocardiography. The authors studied this mode of investigation in 49 consecutive patients (average age 60 +/- 12 years) referred for dobutamine stress echocardiography and who had undergone coronary angiography. The stress echo was carried out according to a standard protocol (5 to 40 m g/kg/min +/- atropine) with additional acquisition of 3 apical views (4, 2 and 3 chambers) with colour Doppler tissue imaging. Analysis of systolic and diastolic myocardial velocities was performed afterwards from digitised data. The different Doppler tissue parameters were measured in 12 left ventricular segments (excluding the apical segments) for each dosage of dobutamine: peak systolic velocity (S), Q-S duration, systolic velocity time integral (ITVS), peak early diastolic velocity (E), peak end diastolic velocity (A). These parameters were analysed throughout the stress for each segment without significant coronary stenosis to define normal values. ROC curves were constructed to determine threshold values of relative changes of velocity (between maximal dobutamine dosage and basal conditions) to improve detection of ischaemia in a segment with coronary stenosis (vessel diameter reduction > or = 70%). Similar diagnostic performances were observed with different systolic and diastolic parameters. The feasibility of measurement of diastolic velocities was, however, reduced (from 29% to 49%). The diagnostic accuracy of each parameter was the same for each vessel territory. A satisfactory concordance was observed between 2D echocardiography and Doppler tissue imaging for the detection of significant coronary stenosis in an analysis by vascular territory. The authors conclude that analysis of myocardial velocities during dobutamine stress echocardiography is feasible. It may be a useful complement for the detection of coronary stenosis during pharmacological stress echocardiography.

Coronary Stenosis↗
PubMed2000

Several protein regions contribute to determine the nuclear and cytoplasmic localization of the influenza A virus nucleoprotein.

A systematic analysis was carried out to identify the amino acid signals that regulate the nucleo-cytoplasmic transport of the influenza A virus nucleoprotein (NP). The analysis involved determining the intracellular localization of eight deleted recombinant NP proteins and 14 chimeric proteins containing the green fluorescent protein fused to different NP fragments. In addition, the subcellular distribution of NP derivatives that contained specific substitutions at serine-3, which is the major phosphorylation site of the A/Victoria/3/75 NP, were analysed. From the results obtained, it is concluded that the NP contains three signals involved in nuclear accumulation and two regions that cause cytoplasmic accumulation of the fusion proteins. One of the karyophilic signals was located at the N terminus of the protein, and the data obtained suggest that the functionality of this signal can be modified by phosphorylation at serine-3. These findings are discussed in the context of the transport of influenza virus ribonucleoprotein complexes into and out of the nucleus.

Amino Acid Substitution↗
PubMed2000

Influenza virus matrix protein is the major driving force in virus budding.

To get insights into the role played by each of the influenza A virus polypeptides in morphogenesis and virus particle assembly, the generation of virus-like particles (VLPs) has been examined in COS-1 cell cultures expressing, from recombinant plasmids, different combinations of the viral structural proteins. The presence of VLPs was examined biochemically, following centrifugation of the supernatants collected from transfected cells through sucrose cushions and immunoblotting, and by electron-microscopic analysis. It is demonstrated that the matrix (M1) protein is the only viral component which is essential for VLP formation and that the viral ribonucleoproteins are not required for virus particle formation. It is also shown that the M1 protein, when expressed alone, assembles into virus-like budding particles, which are released in the culture medium, and that the recombinant M1 protein accumulates intracellularly, forming tubular structures. All these results are discussed with regard to the roles played by the virus polypeptides during virus assembly.

Animals↗
PubMed1999

Mutational analysis of influenza A virus nucleoprotein: identification of mutations that affect RNA replication.

The influenza A virus nucleoprotein (NP) is a multifunctional polypeptide which plays a pivotal role in virus replication. To get information on the domains and specific residues involved in the different NP activities, we describe here the preparation and characterization of 20 influenza A virus mutant NPs. The mutations, mostly single-amino-acid substitutions, were introduced in a cDNA copy of the A/Victoria/3/75 NP gene and, in most cases, affected residues located in regions that were highly conserved across the NPs of influenza A, B, and C viruses. The mutant NPs were characterized (i) in vivo (cell culture) by analyzing their intracellular localization and their functionality in replication, transcription, and expression of model RNA templates; and (ii) in vitro by analyzing their RNA-binding and sedimentation properties. The results obtained allowed us to identify both a mutant protein that accumulated in the cytoplasm and mutations that altered the functionality and/or the oligomerization state of the NP polypeptide. Among the mutations that reduced the NP capability to express chloramphenicol acetyltransferase protein from a model viral RNA (vRNA) template, some displayed a temperature-sensitive phenotype. Interestingly, four mutant NPs, which showed a reduced functionality in synthesizing cRNA molecules from a vRNA template, were fully competent to reconstitute complementary ribonucleoproteins (cRNPs) capable of synthesizing vRNAs, which in turn yielded mRNA molecules. Based on the phenotype of these mutants and on previously published observations, it is proposed that these mutant NPs have a reduced capability to interact with the polymerase complex and that this NP-polymerase interaction is responsible for making vRNPs switch from mRNA to cRNA synthesis.

Amino Acid Sequence↗
PubMed1997

[Clinical, echocardiographic and Doppler outcome in ischemic right ventricular dysfunction associated with inferior wall infarction].

Right ventricular involvement during inferior wall myocardial infarction does not seem to alter long-term clinical prognosis but its specific outcome has not been clearly studied. We have previously demonstrated that pulmonary regurgitant (PR) flow tracings doppler analysis allows the accurate diagnosis of RV involvement, especially when the pressure half-time of PR was < or = 150 ms and the ratio of the minimal velocity to the maximal velocity was < or = 0.5. We studied 40 patients with acute inferior wall myocardial infarction and with PR flow. Doppler echocardiography was obtained during the first day, before discharge (early control) and between 12 and 24 months follow-up (late control). Among 22 patients with RV involvement defined with PR-derived doppler parameters (RVIPR). 8 had right ventricular enlargement and/or wall motion abnormalities, observed in 6 cases at early control and in 4 at late control. Doppler analysis showed remnant RVIPR parameters in 9 patients at early control and 8 among these at late contorl, with no relation with pulmonary artery pressure or other echocardiographic parameters. No clinical, angiographic or therapeutic data predicted these distinct echocardiographic and doppler patterns and the long-term prognosis was not different. At late control, among 12 RVIPR patients which PR-derived doppler parameters were normal at early control, two patients had still RVIPR pattern at late control and described ischemic recurrence. PR flow doppler analysis is a useful tool for diagnosis and outcome evaluation of RV involvement and shows a remnant diastolic dysfunction in half of the patients with acute RV involvement.

Aged↗
PubMed1997

[Dobutamine stress echocardiography; a monocentric experience on 600 consecutive patients. Effect of age].

The increasing indications of dobutamine stress echo in the investigation of myocardial ischaemia, viability and evaluation of the prognosis of coronary artery disease has made this technique a tool of everyday clinical practice. The authors reviewed the results of 600 investigations in consecutive unselected including patients aged over 75. No significant difference was observed with respect to the causes of interruption of the test between patients aged less than 75 (521 patients) and those older than 75 (79 patients). Attaining the target theoretical maximal heart rate was the commonest reason for stopping the test (47 and 48% respectively). Ventricular arrhythmias were not more common (12 and 10% respectively). Twelve cases of ventricular tachycardia were observed, 8 of which were non-sustained; 9 led to interruption of the test. No cases of ventricular fibrillation were observed. A previous history of cardiac arrhythmias was not associated with a higher frequency of arrhythmia during the test (8% in those with a previous history, 4% in those patients without). Supraventricular arrhythmias were significantly more common in patients over 75 years of age (15 versus 8%, p = 0.046). Dobutamine stress echocardiography' is feasible in a population of unselected patients, including those over 75. Therefore, age does not represent a limitation to the extension of this investigation.

Adult↗
PubMed1996

The 5' ends of Thogoto virus (Orthomyxoviridae) mRNAs are homogeneous in both length and sequence.

Thogoto (THO) virus is a tick-borne member of the Orthomyxoviridae whose genome consists of six segments of linear, negative sense, single-stranded RNA. To gain insight into the mechanism by which viral mRNA transcripts are initiated, poly(A)+ RNA isolated from THO virus-infected cells was characterized by (i) primer extension experiments, (ii) immunoprecipitation studies with an anticap monoclonal antibody, (iii) direct sequencing analysis of the isolated RNA, and (iv) cloning and sequencing of individual mRNA molecules. The results indicated that THO virus mRNAs are capped and homogeneous in both length and sequence at their 5' end. These findings contrast with the situation found in all other segmented, negative sense or ambisense, single-stranded RNA viruses so far analyzed in which the 5' ends of viral mRNAs are heterogeneous in length and sequence. These results are discussed in terms of the mechanism used by THO virus to initiate mRNA synthesis.

Poly A↗
PubMed1995

Identification of an RNA binding region within the N-terminal third of the influenza A virus nucleoprotein.

The influenza A virus nucleoprotein (NP) has been examined with regard to its RNA-binding characteristics. NP, purified from virions and devoid of RNA, bound synthetic RNAs in vitro and interacted with the ribonucleotide homopolymers poly(A), poly(G), poly(U), and poly(C) in a salt-dependent manner, showing higher binding affinity for polypyrimidine homopolymers. To map the NP regions involved in RNA binding, a series of deleted forms of the NP were prepared, and these truncated polypeptides were tested for their ability to bind poly(U) and poly(C) homopolymers linked to agarose beads. Proteins containing deletions at the N terminus of the NP molecule showed reduced RNA-binding activity, indicating that this part of the protein was required to bind RNA. To identify the NP region or regions which directly interact with RNA, proteins having the maltose-binding protein fused with various NP fragments were obtained and tested for binding to radioactively labeled RNAs in three different assays: (i) nitrocellulose filter binding assays, (ii) gel shift assays, and (iii) UV light-induced cross-linking experiments. A maltose-binding protein fusion containing the N-terminal 180 amino acids of NP behaved as an RNA-binding protein in the three assays, demonstrating that the N terminus of NP can directly interact with RNA. This NP region could be further subdivided into two smaller regions (amino acids 1 to 77 and 79 to 180) that also retained RNA-binding activity.

Amino Acid Sequence↗
PubMed1995

[Morphological study by transesophageal echocardiography and clinical aspects of ruptured chordae tendineae in the elderly].

Ruptured mitral chordae tendinae is a classical complication of myxomatous mitral valves or Barlow's syndrome. This complication is controversial in non-myxomatous mitral valve. Of 91 consecutive patients with mitral valve prolapse examined over an 18 months period by transthoracic and transesophageal echocardiography, 42 (18 women and 24 men) with an average age of 76 +/- 8 years (60-93 years) had ruptured mitral chordae tendinae. The thickness of the anterior mitral leaflet measured at the distal third of the valve by transesophageal echocardiography enabled the identification of two groups of patients; group I: > 3 mm (24 patients), average 4.8 +/- 0.8 mm and group II: < or = 3 mm (18 patients), average 2.6 +/- 0.3 mm. The diameter of the mitral ring and left atrium, the length of the anterior mitral leaflet, the left ventricular end diastolic dimensions and fractional shortening, were measured by transthoracic 2D echocardiography (mitral ring) and M mode (other parameters). Ruptured chordae were detected in only 13 cases (31%) by transthoracic echocardiography; 38% were asymptomatic and a chance finding at transesophageal echocardiography. No significant difference was observed between the two groups with respect to age, gender presence of hypertension, dimensions of the cardiac chambers, fractional shortening or localisation of the prolapse related to the ruptured chordae. Fifty-eight per cent of patients in group I were in NYHA functional classes 3-4 as compared to 16% in group II (p < 0.02). The size of the left atrium was significantly greater in group I, 51 +/- 8 mm vs 38 +/- 7 mm (p < 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Age Factors↗
PubMed1995

[Program of hypertransfusion and chelation with desferrioxamine in 10 patients with thalassemia major].

PURPOSE: Thalassaemia maior is an inherited severe anaemia due to abnormal haemoglobin synthesis. Hypertransfusion therapy is based on the reduction of ineffective erythropoiesis and improvement of the anaemia. To prevent iron overload, continuous chelation therapy was performed with desferrioxamine (DFO). The efficacy of such management in 10 thalassaemia maior patients followed-up for 11 years has been evaluated. PATIENTS AND METHODS: Packed red-cell transfusions were administered to maintain haemoglobin rates over 100 g/L; 40 mg/Kg DFO was given five days a week subcutaneously. The mean age at the start of such treatment was 9.3 years. Clinical problems due to iron overload were evaluated, such as heart function, growth and development, endocrinopathies, along with DFO toxicity and complications of transfusion (positive indirect antiglobulin test (IAT), hepatitis, HIV infection). RESULTS: Two patients died of heart haemosiderosis. The mean ferritin values at the end of the study were around 3.031 mg/mL. Heart dysfunction was seen in 2 cases; 2 patients had retarded growth, decreased IGF-1 being found in both; 3 cases had hypogonadotropic hypogonadism, and 2 had clinical hypoparathyroidism. Bilateral opacification of the eye lens appeared in one patients as a consequence of prolonged DFO therapy. Positive IAT was found in 3 cases, and one patient developed positive hepatitis C serology. CONCLUSIONS: Control of iron deposits by iron chelators can prevent the damages of iron overload. Adequate accomplishment of programmes may be difficult, especially in children.

Adolescent↗
PubMed1994

Additive haemodynamic effects of piroximone and prostacyclin in severe chronic heart failure.

This study was undertaken to assess the haemodynamic effects of the combined infusion of prostacyclin and piroximone, a phosphodiesterase inhibitor, in 18 patients with severe congestive heart failure. Right heart catheterization was performed with a Swan-Ganz thermodilution catheter and arterial blood pressure was monitored using a radial line. After baseline haemodynamic measurements, prostacyclin was administered in all patients at the incremental infusion rate of 2, 4, 6 and 8 and 10 ng.kg-1.min-1 during 15 min each. After recovery of baseline haemodynamics, patients were randomly assigned to the piroximone infusion rate of 5 or 10 micrograms.kg-1.min-1 or placebo. After 24 h piroximone or placebo infusion, the same prostacyclin protocol was applied. Prostacyclin infusion added to piroximone resulted in a significant improvement in haemodynamics, as compared to the group receiving prostacyclin added to placebo. As compared to the curve observed with the placebo infusion, 10 ng.kg-1.min-1 prostacyclin infusion resulted in a further increase in cardiac index, by 41 and 38% (P < 0.01) at the piroximone-infusion rates of 5 and 10 micrograms.kg-1.min-1, respectively, whereas systemic vascular resistance decreased by 25 and 21%, respectively (P < 0.01). Additionally, a further decrease in pulmonary capillary wedge pressure by 13 and 11% (P < 0.05) and in pulmonary vascular resistance by 21 and 19% (P < 0.05) was observed at the piroximone-infusion rates of 5 and 10 micrograms.kg-1.min-1, respectively. Consequently, stroke work index increased significantly, as compared to the group receiving prostacyclin added to placebo. This haemodynamic improvement occurred without significant changes in heart rate and mean arterial pressure. Thus, this study shows that in patients with severe congestive heart failure, short-term infusion of prostacyclin is safe and has additive haemodynamic effects on phosphodiesterase inhibitors.

Adult↗
PubMed1994

Effects of propofol and thiopental on coronary blood flow and myocardial performance in an isolated rabbit heart.

BACKGROUND: Some clinical and experimental studies suggest that propofol decreases myocardial contractility and relaxation, whereas others report preserved cardiac function. To investigate the effects of propofol on intrinsic contractility and relaxation, increasing concentrations of propofol were infused in isolated blood-perfused rabbit hearts. Equimolar concentrations of thiopental were infused as a reference group. METHODS: Coronary blood flow, left ventricular contractility and relaxation (as maximal positive and negative left ventricular pressure derivatives [dP/dtmax and dP/dtmin], respectively), and myocardial oxygen consumption (MvO2) were measured during infusion of 10-1,000 microM propofol in blood-perfused hearts. To determine whether the effects of propofol depend on the heart's perfusate, propofol also was infused in isolated buffer-perfused rabbit hearts. In addition, the effects of propofol solvent were investigated in blood- and buffer-perfused preparations. RESULTS: In blood-perfused preparations, coronary blood flow increased with propofol concentrations greater than 30 microM and with 300 and 1,000 microM thiopental. Left ventricular dP/dtmax and dP/dtmin remained unchanged with propofol and decreased with concentrations of thiopental equal to or greater than 30 microM. MvO2 increased with 1,000 microM propofol, whereas coronary venous oxygen tension and content remained unchanged. MvO2 decreased with thiopental associated with a significant increase in coronary venous oxygen tension and content. In six buffer-perfused hearts, basal coronary blood flow was much greater and MvO2 less than in blood-perfused hearts. Left ventricular dP/dtmax and dP/dtmin decreased with 30, 100, and 300 microM propofol. Propofol vehicle did not change coronary blood flow, myocardial performance, or MvO2 of blood- or buffer-perfused hearts. CONCLUSIONS: When compared to a reference drug such as thiopental, propofol did not depress the myocardial performance of blood-perfused rabbit hearts. The type of the perfusate (blood vs. buffer), however, had a major influence on the myocardial effects of propofol.

Animals↗
PubMed1994

Synthesis of biologically active influenza virus core proteins using a vaccinia virus-T7 RNA polymerase expression system.

An in vivo system in which expression of a synthetic influenza virus-like chloramphenicol acetyltransferase (CAT) RNA is driven by influenza virus proteins synthesized from cloned cDNAs has been developed. Expression of the four influenza virus core proteins (nucleoprotein, PA, PB1 and PB2) was performed by transfection of four pGEM recombinant plasmids, each containing one of the four viral genes, into cell cultures previously infected with a vaccinia virus recombinant encoding the T7 RNA polymerase (vTF7-3). When a naked negative-sense influenza virus-like CAT RNA was transfected into cells expressing the four influenza virus proteins, CAT activity was detected in the cell extracts, demonstrating that the expressed proteins had RNA-synthesizing activity. In this system, CAT RNA templates containing additional nucleotides at the 3' end were also expressed, resulting in CAT activity. This showed that the influenza virus polymerase can recognize its promoter when located internally on an RNA template. In influenza virus-infected cells however, CAT activity was detected only when the CAT RNA contained the viral promoter at the exact 3' end and was transfected as in vitro assembled ribonucleoprotein. These results are discussed in terms of the different requirements of the two helper systems for expression of an exogenously added RNA.

Animals↗