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M Pezzano

Publications and source records attributed to M Pezzano.

At least 37 records · Page 2Linked to original sources
PubMed1997

[Ultrasound-guided pericardial drainage. Experience in 34 consecutive patients].

OBJECTIVES: Transthoracic echoguided puncture of the pericardium can be an alternative to surgical drainage. We report our experience with this technique acquired over the last 11 years. PATIENTS AND METHODS: From January 1984 to September 1995, 34 consecutive patients in the cardiology intensive care unit (mean age 56.5 +/- 13 years) underwent echoguided pericardial puncture for poorly tolerated pericardial effusion. The underlying cause was neoplasia (n = 22), idiopathic disease (n = 5), autoimmune disease (n = 2), post-surgical complication (n = 2 including 1 on hemodialysis), infection (n = 1), antivitamin K therapy (n = 1) and disseminated vascular coagulation (n = 1). The subxyphoid (n = 33) or left parasternal (n = 1) route was used under echographic guidance. Intrapericardial contrast allowed verification of the catheter position. The mean quantity of fluid removed was 585 +/- 390 ml. The fluid was hemorrhagic (n = 19), clear (n = 10) or serohematic (n = 4). Aspiration was continued in 16 patients after the initial puncture for a mean 64 hours. The mean total volume of fluid was 750 +/- 330 ml. RESULTS: There was one death during puncture which was found to be unrelated to the procedure after anatomic verification. In two cases, the left ventride was punctured without any consequence. Collapsus occurred during puncture in 2 patients with pulmonary sepsis. Minor incidents were: 6 vasovagal syndromes at puncture with paroxysmal supraventricular rhythm disorder during aspiration. Prior to 1988, surgical drainage was required in 5 patients for persistent or recurrent effusion. Since that time, continuous aspiration has been used in all patients and no surgical drainage has been required. Short-term prognosis depends on the underlying cause (6 deaths at 1 month). CONCLUSION: Echoguided pericardial puncture is a simple procedure which rapidly improves cardiac hemodynamics in these particularly fracle patients. Continuous aspiration avoids subsequent surgical drainage for persistent or recurrent effusion.

Drainage↗
PubMed1996

Positive selection by thymic nurse cells requires IL-1 beta and is associated with an increased Bcl-2 expression.

A temperature-sensitive line of thymic nurse cells (tsTNC-1) that maintains the ability to selectively internalize immature alpha beta TCRloCD4+CD8+ thymocytes in vitro was used in long-term coincubation experiments to determine nurse cell function during the process of MHC restriction. The thymocyte subset released from its association with TNCs contained both viable and apoptotic cells. The cells that remained within intracytoplasmic vacuoles died through the process of programmed cell death. Surviving or rescued thymocytes in the released population displayed an increase in Bcl-2 protein expression. The rescue activity of TNCs was drastically reduced with the addition of antibodies against either class I or class II MHC antigens to cocultures. A subset of the TNC-rescued population matured from the alpha beta TCRloCD69- phenotype to alpha beta TCRhiCD(69+)-expressing cells only when IL-1 beta was added to cocultures. These results suggest that TNC rescue of early double-positive thymocytes from apoptosis is associated with an interaction between the TCR and the MHC and the onset of Bcl-2 expression. Maturation of thymocytes within the TNC-rescued population requires the costimulatory effects of IL-1 beta.

Animals↗
PubMed1996

[Spontaneous intracardiac contrast and embolic risk].

Spontaneous contrast in the form of smokey echos in the cardiac chambers is considered to be a risk factor for thromboembolism. The aggregation of red blood cells results in larger target which diffuse a measurable in vitro ultrasonic signal. The phenomenon of erythrocytic aggregation is dependent on the red cells themselves, the plasma fibrinogen and conditions of blood flow. The other constituents of the blood only reflect a small amount of ultrasound, usually undetectable. Transoesophageal echocardiography with high frequency transducers (5 MHz) positioned in close proximity to the cardiac chambers, has become the reference method for detecting spontaneous contrast. This phenomenon is almost exclusively observed in the left atrium and left auricle and rarely in the other cardiac chambers or descending aorta. In pathological situations, spontaneous contrast is essentially implicated in two conditions: mitral valve obstacles and non-valvular atrial fibrillation. Conversely, moderate to severe mitral regurgitation is a negative predictive factor of spontaneous contrast. However, a purely qualitative appreciation of spontaneous contrast which may be influenced by the gain setting and technical specifications of the echocardiograph, and the subjectivity of the operator, is an important limitation. Therefore, the identification of quantitative markers of spontaneous contrats and new therapeutic antithrombotic protocols remain essential.

Atrial Fibrillation↗
PubMed1995

Thymic nurse cell rescue of early CD4+CD8+ thymocytes from apoptosis.

We have now developed temperature sensitive lines of thymic nurse cells (TNCs), using the SV40 viral mutant tsA58, that maintain the ability to selectively internalize a subpopulation of alpha beta TCR+CD4+CD8+ thymocytes in vitro. One line, tsTNC-1, was shown to be able to rescue a subset of CD4+CD8+ thymocytes from programmed cell death at 32 degrees C, the temperature at which binding and internalization were detected. Rescue was significantly diminished at 38 degrees C, the temperature at which thymocyte binding was not observed. The rescued population of thymocytes showed a reduced level of apoptosis as measured by the DNA fragmentation assay. TNC rescue resulted in a shift of CD4+CD8+ thymocytes from immature TCRlow PNArhigh cells to the more mature TCRint PNArlow phenotype but no changes in cell surface levels of HSA nor CD69 were detected. The rescue activity of tsTNC-1 cells at 32 degrees C was significantly reduced with the addition of antibodies to either class I or class II MHC antigens. These results suggest that we have established TNC lines, using the SV40 viral mutant tsA58, that have the ability to rescue a subset of the TNC interactive thymocyte population from programmed cell death. The thymocyte population rescued by TNCs matures to a phenotype within the double positive stage of development that is indicative of positive selection.

Animals↗
PubMed1993

The binding, internalization, and release of thymocytes by thymic nurse cells.

Recent studies in our laboratory have described the development of the SV40-transformed thymic nurse cell (TNC) line SVT-II2, that maintains the ability to internalize thymocytes in vitro. SVT-II2 cells were shown to bind and internalize a subset of the alpha beta TCR+, CD4+CD8+ thymocyte population exclusively. Also, SVT-II2 cells express cell surface class I and class II MHC antigens. These data are consistent with reports that suggest that TNCs may have a role in thymic education. In this report, we used scanning electron microscopy, transmission electron microscopy, and long-term video microscopy to study binding, internalization, and release of thymocytes by TNCs. The results of these experiments showed the internalization event to be selective and dynamic. The process appears to involve programmed cooperation between the two cell types that terminates with the release of selected thymocytes. Although no changes in thymocyte cell surface phenotype were detected as a result of their interaction with TNCs in vitro, over 90% remained viable after a 48-hr incubation period.

Animals↗
PubMed1993

[Transesophageal echography and left intraventricular echo-contrast. Complete regression of a large thrombus of the left ventricle with anticoagulant therapy].

The authors report the case of a 69 year old man with a large left ventricular thrombosis complicating anterior myocardial infarction occurring three years previously for which anticoagulant therapy had to be withdrawn. The discussion is based around the large size of the thrombus, its complete regression with anticoagulant therapy (heparin and coumarin-derivative) and also around the detection of spontaneous echo contrast in the left ventricle by transoesophageal echocardiography. This case underlines the probable risk of withdrawing anticoagulant therapy in patients with severe left ventricular dysfunction and left ventricular spontaneous contrast.

Aged↗
PubMed1993

[Reperfusion arrhythmia].

Reperfusion arrhythmias were described from the first trials of intracoronary thrombolysis for myocardial infarction. The prevalence of ventricular fibrillation during intravenous thrombolysis is low (< 7%) and comparable to that observed with classical treatment. Holter recording shows that ventricular tachycardia and accelerated idioventricular rhythms occur in over 80% of cases. These arrhythmias are generally well tolerated and do not require specific therapy. A bradycardia-hypotension syndrome is observed in about a quarter of reperfused patients, nearly always in inferior wall infarction. It normally resolves spontaneously or after atropine or vascular filling. Reperfusion is associated with a clearcut increase in the number of episodes of arrhythmia. Some arrhythmias such as sustained ventricular tachycardia, early accelerated idioventricular rhythms (occurring in the first 6 hours) or the bradycardia-hypotension syndrome may be considered as non-invasive criteria of reperfusion. More severe ischemia and sudden reperfusion favour the arrhythmogenicity of reperfusion in the animal. Recent data suggest that this may be the case in the clinical context. In some uncontrolled studies, lidocaine, betablockers and aspirin did not affect the prevalence of the arrhythmias. Preliminary trials indicate that flunarizine and captopril may reduce the incidence of reperfusion arrhythmias in man. Ventricular arrhythmias and myocardial stunning could be the result of sa single phenomenon (the extent of the ischemic lesions or reperfusion lesions). Studies currently under way should clarify the relationship between the incidence of arrhythmias, the severity of stunning and myocardial recovery. Protocols evaluating therapeutic interventions on the reperfusate should include Holter monitoring.

Animals↗
PubMed1992

Holter recording of ventricular arrhythmias during intravenous thrombolysis for acute myocardial infarction.

Ventricular arrhythmias during thrombolysis for acute myocardial infarction and their relation to coronary artery patency were examined. Twenty-four-hour Holter monitoring was begun 3.1 +/- 0.2 hours after onset of pain in 40 patients (age 54 +/- 1.6 years; anterior infarction 42.5%) treated with streptokinase (42.5%) or recombinant tissue-type plasminogen activator (57.5%) (delay from pain 3.3 +/- 0.2 hours). A Marquette 8000 computer was used for Holter analysis. The infarct-related artery was considered as patent (72.5%) or non-patent (27.5%) according to coronary angiography (delay from pain 26.7 +/- 2.5 hours; 60% less than 24 hours). Ventricular arrhythmias were present in all patients. Tolerance was good (1 cardioversion for ventricular fibrillation). The incidence of accelerated idioventricular rhythm was not different between patients with a patent and nonpatent artery (90 vs 82%), nor for ventricular tachycardia (VT) (83 vs 73%). Coronary artery patency was associated with a 14-, 13- and 32-fold increase of ventricular premature complexes, VT and accelerated idioventricular rhythms, respectively. The increased incidence of sustained VT (patent 38%; nonpatent 0%; p less than 0.05) and early (before the first 6 hours) accelerated idioventricular rhythm (patent 76%; nonpatent 18%; p less than 0.01) associated with artery patency suggests that these arrhythmias may be noninvasive diagnostic criteria for reperfusion (sensitivity 38 vs 76%, and specificity 100 vs 82%). A positive correlation was found between the frequency of ventricular premature complexes and VT, and peak creatine kinase.

Arrhythmias, Cardiac↗
PubMed1992

Thymic nurse cells exclusively bind and internalize CD4+CD8+ thymocytes.

Thymic nurse cells (TNC) contain 20-200 thymocytes within specialized vacuoles in their cytoplasm. The purpose of the uptake of thymocytes by TNCs is unknown. TNCs also have the capacity to present self-antigens, which implies that they may serve a function in the process of thymic education. We have recently reported the development of thymic nurse cell lines that have the ability to bind and internalize T cells. Here, we use one of these TNC lines to identify the thymocyte subpopulation(s) involved in this internalization process. TNCs exposed to freshly isolated thymocytes bind and internalize CD4 and CD8 expressing thymocytes (CD4+CD8+ or double positives) exclusively. More specifically, a subset of the double-positive thymocyte population displayed binding capacity. These double-positive cells express cell surface alpha beta type T cell antigen receptor (TCR), as well as CD3 epsilon. Binding was not inhibited in the presence of antibodies against CD3, CD4, CD8, Class I antigens, or Class II antigens. These results describe two significant events in T cell development. First, TNCs exclusively bind and internalize a subset of alpha beta TCR expressing double-positive T cells. Also, binding is facilitated through a mechanism other than TCR recognition of major histocompatibility complex antigens. This suggests that thymocyte internalization may be independent of the process used by TNCs to present self-antigen.

Animals↗
PubMed1992

[Early hospital discharge after uncomplicated myocardial infarction: strategies].

Considerable advances have been seen in recent years in the diagnostic and therapeutic management of myocardial infarction. Furthermore, approximately 50% of patients hospitalised for a myocardial infarction have shown no evidence of any complication by the 3rd day of the disease. With this in mind, the authors show that early discharge from hospital at the end of the first week is possible in perfect safety for the majority of these patients, most often treated by thrombolysis, based upon precise knowledge of the severity of arterial disease and of left ventricular function, and the detection of any residual ischemia or possible rhythm disturbances. Only patients with three vessel disease have a higher risk of residual angina and should theoretically be excluded from such programmes. Ambulatory rehabilitation is an essential adjuvant, contributing to a faster return to work and a decrease in health care costs.

Electrocardiography↗
PubMed1992

[Holter monitoring of ventricular arrhythmia during the 24 first hours of myocardial infarction treated with intravenous thrombolysis].

The aim of this study was to assess ventricular arrhythmias after intravenous thrombolysis for acute myocardial infarction and to determine their relationship with coronary artery patency. A 24 hour Holter recording was started 3.1 +/- 0.2 hours after the onset of pain in 40 patients (age 54 +/- 1.6 years, 42.5% anterior infarcts) treated by streptokinase (42.5%) or tissue plasminogen activator (57.5%) within 3.3 +/- 0.2 hours of the beginning of symptoms. The arrhythmias were analysed on a Marquette 8000 computer. Coronary angiography was systematic and was performed 26.7 +/- 2.5 hours (within 4 hours in 60% of patients) after the onset of pain to define coronary artery patency (TIMI 2 and 3: 72.5%) or occlusion (TIMI 0 or 1: 27.5%). Ventricular arrhythmias were common and generally well tolerated (one defibrillation for ventricular fibrillation). Accelerated idioventricular rhythms and ventricular tachycardias were equally prevalent in patients with patent arteries (90% and 83%) as with occluded arteries (82% and 73%). The prevalence of sustained ventricular tachycardias (> 15 complexes) and of early accelerated idioventricular rhythms (< or = 6 hours) was significantly higher in patients with patent coronary arteries: 38% versus 0% (p < 0.05) and 76% versus 18% (p < 0.01). These arrhythmias may be considered to be non-invasive markers of early coronary reperfusion, with a sensitivity of 38 and 76% and a specificity of 100 and 82%. Coronary patency was associated with higher numbers of ventricular extrasystoles, ventricular tachycardias and accelerated idioventricular rhythms by a factor of 14, 13 and 32 respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

[Large thrombus in the left atrium and rheumatic mitral stenosis. Value of cardiac imaging].

Thromboses in the left atrium, which are a commonplace complication of mitral stenoses with major dilatation of the left atrium lead to a major risk of systemic embolism. It is important to discover them, because they constitute a contraindication to mitral valvuloplasty. The authors report the case of a large left intra-atrial thrombus complicating a pure, tight, mitral stenosis. They also highlight the value of new medical imaging techniques in cardiology: chest CT scan, nuclear magnetic resonance and cardiac scintigraphy. Subsequently, transesophageal cardiac ultrasound, not available in France at the time for this patient, has become the reference method for visualizing and detecting left intra-atrial thrombi.

Aged↗
PubMed1991

The immortalization of thymic nurse cells by SV40 virus.

Thymic nurse cells (TNCs) are stromal elements that contain between 20 and 200 T cells within their cytoplasm. Because of this unique feature they are believed to play a role in thymocyte development. Unfortunately, it has been difficult to obtain pure TNCs in quantities sufficient for extensive evaluation of their thymic function. As a result, only a limited amount of information is available that characterizes TNCs or the T cell population(s) found within their cytoplasm. We have now used SV40 to infect and immortalize TNCs from C57BL/6 mice. SV40-transformed TNCs were found to specifically bind and internalize cells from an immature thymocyte line isolated in our laboratory. These results describe a method of obtaining pure populations of TNCs for future studies of their thymic function, and suggest that binding to specific subpopulations of lymphoblasts may be necessary for internalization.

Animals↗
PubMed1989

Relationship between mixed venous oxygen saturation and cardiac index in patients with chronic congestive heart failure.

The use of mixed venous oxygen saturation (SvO2) in patients with chronic congestive heart failure (CHF) has been advocated to analyze the action of therapy on cardiac index (CI). To evaluate the relationship between CI and SvO2, ten CHF patients (mean age 65 years) were studied before and one, two, three, four (T4), six, eight and 24 hours after oral administration of an angiotensin converting enzyme (ACE) inhibitor (perindopril, 4 mg). At T4, a 12 percent increase in CI (p less than 0.01) was associated with a 16 percent decrease in arteriovenous oxygen difference (p less than 0.01), a 13 percent increase in mixed venous oxygen pressure (PvO2) (p less than 0.01), and a 9 percent increase in SvO2 (p less than 0.05) with no significant change in arterial oxygen pressure. There was no correlation between CI and SvO2 (r = 0.22) and between CI and PvO2 (r = 0.23). Individual analyses were performed and patients were divided into two groups based on CI versus SvO2 r value; group 1, n = 6, r greater than 0.65 (0.65-0.90), group 2, n = 4, r less than 0.65 (0.14-0.20). The lack of correlation in group 2 was due to a drug-dependent increase in oxygen consumption (VO2) +18 percent vs -3 percent in group 1 (p less than 0.05) associated with a lack of increase in PvO2 +3 percent vs +14 percent in group 1 (p less than 0.05) despite a similar increase in oxygen availability +19 percent versus +16 percent. It was concluded that (1) a correlation between CI and SvO2 is not found in every patient with CHF; (2) the lack of correlation in four out of our ten patients was due to an associated and significant increase in CI and VO2 in group 2; (3) group 2 patients probably had an important oxygen debt before treatment; (4) SvO2 cannot be used instead of CI to determine the hemodynamic consequences of the use of cardiovascular drugs.

Administration, Oral↗
PubMed1988

[Listeria rhombencephalitis caused by Listeria monocytogenes with a cerebrospinal fluid initially normal].

A case of rhombencephalitis due to Listeria monocytogenes in a non immunocompromised patient, with initially normal cerebrospinal fluid, was marked by potentially fatal neurovegetative disorders and severe neurological sequelae partly due to delay in diagnosis and treatment. The possibility of Listeria infection should be considered in patients with fever and cranial nerves deficits, in order to initiate an appropriate antibiotic therapy and to keep the subject under close monitoring in an intensive care unit.

Aged↗
PubMed1988

Comparison of non-protected lower respiratory tract secretions and protected specimen brush samples in the diagnosis of pneumonia.

The aim of this prospective study was to compare the results obtained with the non-protected lower respiratory tract secretions samples (LRS) with the protected specimen brushes (PSB) performed through a fiberoptic bronchoscope in mechanically ventilated patients, when pneumonia was suspected. The diagnosis of pneumonia was ultimately made at the end of the hospitalisation, in a double-blind manner by 2 members of the medical staff not aware of the bacteriologic results of LRS and PSB. LRS and PSB were performed in 24 patients. PSB culture was considered as positive at a level of 10(3) colony-forming units per milliliter (cfu/ml) microorganisms. Twenty-five samples from 24 patients were divided as follows: (1) LRS (-) and PSB (-) 5 samples: the clinical diagnosis of pneumonia was never established. (2) LRS (+) and PSB (+) 10 samples: the clinical diagnosis of pneumonia was always established, 2 microorganisms were involved 4 times and 1 microorganism 6 times. (3) LRS (+) and PSB (-) 10 samples: the clinical diagnosis pneumonia was retained in 3 with the possibility of false negative PSB. We conclude that (1) a negative LRS eliminated the diagnosis of pneumonia without PSB; (2) a positive LRS was not sufficient to diagnose pneumonia since PSB was negative in 50% of all LRS (+) cases; (3) the possibility of a false negative PSB must be kept in mind particularly in patients previously treated with antibiotics; (4) 2 microorganisms may be responsible for the pneumonia if the previously determined, as significant, bacteriological count (greater than or equal to 10(3) cfu/ml) appears to be accurate.

Adult↗
PubMed1988

Pharmacokinetics of pefloxacin and amikacin administered simultaneously to intensive care patients.

Ten adult patients with severe infections in an intensive care unit were treated simultaneously with 6 mg/kg pefloxacin and 7.5 mg/kg amikacin, infused i.v. over 1 h every 12 h for 5 days. Twelve h after the last infusion, pefloxacin alone was administered orally (400 mg tablet) every 12 h for 10 days. The pharmacokinetics of pefloxacin and its main metabolites, norfloxacin and pefloxacin N-oxide, were determined after the first (Day 1) and last (Day 5) infusions and after the last oral dose (Day 15). The kinetics of amikacin was determined after the first and the last infusion. The maximal and minimal steady-state plasma concentrations of amikacin were 27.3 and 3.3 mg/l. The total plasma clearance was 83.1 and 67.0 ml/min after the first and the last infusions, respectively, and the half-life was 3.9 and 5.0 h. The maximal and minimal steady-state plasma concentrations of pefloxacin were 13.1 and 7.9 mg/l after i.v. infusion and 13.4 and 9.0 mg/l after oral administration. Pefloxacin elimination (t1/2) increased from 11.3 h after the first infusion to 19.4 h after the last infusion and 21.1 h after the last oral dose. Total body clearance decreased from 90.8 (Day 1) to 51.9 (Day 5) and 56.4 ml/min (Day 15). The volume of distribution did not change significantly over the course of pefloxacin. Mean steady-state plasma concentrations of norfloxacin and pefloxacin N-oxide were respectively 0.5-0.6 mg/l and 0.9-1.3 mg/l after intravenous and oral administration of pefloxacin. There were no pharmacokinetic interaction between the drugs. The dosage regimen led to plasma concentrations of pefloxacin and amikacin within their therapeutic range.

Aged↗