Search PubMed⌕ Search

Biomedical subjects

M Amor

Publications and source records attributed to M Amor.

At least 55 records · Page 3Linked to original sources
PubMed1983

Genetic polymorphism of lambda 1 and lambda 3 immunoglobulin light chains in the Mus subgenus.

Several inbred or partially inbred mouse strains derived from wild mice of different Mus subgroups were surveyed for expression of lambda 1 light chain. One strain, SPE, expressed little or no lambda 1 chains. Two populations of antibodies were obtained by immunization of SPE mice with lambda 1 light chain isolated from the BALB/c J558 (alpha, lambda 1) myeloma protein. One population of antibodies recognized lambda 1 allotypic determinants located on the C terminal fragment beginning at the residue 176. A second population was directed against epitopes present on both lambda 1 and lambda 3 chains. These determinants, which were detected in all strains tested with the exception of SPE, were located in the V region. This result is in concordance with recent DNA studies showing that the lambda 1 and lambda 3 isotype use the same V lambda 1 genes (Blomberg, B. et al., Proc. Natl. Acad. Sci. USA 1981. 78: 3765). Whether the V epitopes recognized by SPE antibodies are allotypic or isotypic in nature is not certain.

Animals↗
PubMed1982

[Effects of isosorbide dinitrate injection on acute myocardial infarction. A haemodynamic and gamma-angiographic study (author's transl)].

The haemodynamic and gamma-angiographic effects of isosorbide dinitrate (ISDN) injection were evaluated in 18 patients with recent myocardial infarction by measuring diastolic (DPAP) and systolic (SPAP) pulmonary artery pressures, diastolic (DAP) and systolic (SAP) systemic arterial pressures, cardiac index (CI) and heart rate (HR). Total ejection fraction (EF) was measured by radionuclide angiography. Within the first hour of treatment, there was a significant fall in DPAP (from 25.11 +/- 6.5 to 18.3 +/- 6 mmHg), SPAP (from 47 +/- 11.5 to 36.6 +/- 10 mmHg) and SAP (from 140 +/- 27.8 to 123 +/- 20 mmHg). Changes in DAP, CI and HR were not significant. The drug produced a significant increase in EF (from 32.6 +/- 15 to 35.3 +/- 15 p. cent). On the basis of these results the patients could be divided into three categories: -- Group I patients (n = 5) with EF greater than 45, in whom the haemodynamic effects (fall in DRAP from 20.8 +/- 4.2 to 16.3 +/- 3 mmHg) and the gamma-angiographic effects (increase in EF from 53.8 +/- 6 to 58.6 +/- 3 p. cent) were favourable. -- Group II patients (n = 5) with EF less than 40, in whom the haemodynamic effects (fall in DRAP from 29 +/- 8.5 to 17.8 +/- 6 mmHg) and the gamma-angiographic effects (increase in EF from 23 +/- 9 to 34 +/- 7 p. cent) were still favourable. -- Group III patients (n = 8) with low EF, in whom there were no significant changes in haemodynamic effects (DPAP from 25.3 +/- 3 to 23.4 +/- 5 mmHg) and gamma-angiographic effects (EF from 26 +/- 6 to 25 +/- 5 p. cent). This group corresponds to cases with very extensive necrosis of unfavourable outcome (4 deaths). One may therefore consider that the lack of effectiveness of ISDN in subjects with left ventricular failure and low EF is of poor prognosis and requires more aggressive therapy.

Adult↗
PubMed1981

[A new radioisotopic method of studying local ejection fractions. Application to the study of abnormalities of left ventricular contraction].

The authors describe a new method of segmental analysis of the left ventricle by equilibrium gamma cinecardiography. The left ventricle in the left anterior oblique projection was divided into 16 triangular sectors with reference to the centre of gravity of the radioactivity of the end diastolic frame. The following parameters were calculated for each sector (the spatial equivalent of a quarter of an orange): end diastolic, end systolic and ejection activity and the regional ejection fraction. The percentage of normal and asynergic regions was deduced. The end diastolic activity of regions with ejection fractions of over 0,47 was compared to the total end diastolic activity to obtain the percentages. This method of segmental division has the advantages of being completely automatic, based entirely on an objective reference calculated by computer and of giving very reproductible quantitative results. The clinical applications in a series of I400 patients examined by this method were numerous (the detection of dyskinesia in acute myocardial infarction). It was particularly useful in chronological and follow-up studies (exercise scintigraphy before and after glyceryl trinitrite).

Cardiac Output↗
PubMed1980

[Left ventricular function in coronary disease. Gamma cineangiocardiography at equilibrium with right atrial pacing and nitroglycerine].

25 patients (2 normal and 23 coronary artery disease) were studied by 99m Tc gated blood pool scans at rest, with right atrial pacing, right atrial pacing and nitroglycerine, and finally nitroglycerine alone. Total and regional ejection fractions were measured and the induced and reversible asynergy with right atrial pacing and nitroglycerine was also assessed.

Cardiac Pacing, Artificial↗
PubMedDate not supplied

Stent placement in the renal artery: three-year experience with the Palmaz stent.

PURPOSE: To evaluate the long-term results of stent placement in the renal arteries. PATIENTS AND METHODS: From January 1990 to August 1994, 59 hypertensive patients underwent 64 stent placement procedures. Indications were residual stenosis after percutaneous transluminal renal angioplasty in 42 patients, restenosis in 20 patients, and acute dissection in two patients. Follow-up (mean, 14 months) was obtained in 54 patients. Six-month restenosis rates were based on results of arteriography, and even more long-term patency rates were based on duplex ultrasound. RESULTS: Technical success was achieved in all patients. Major complications occurred in two patients. No minor or puncture-site complications were observed. The overall 6-month restenosis rate was 1.6% (2.9% for ostial lesions). Survival analysis with the Kaplan-Meier method showed primary and secondary patency rates of 92% +/- 3.6 and 98% +/- 1.9, respectively, at 1 year and 79% +/- 8.8 and 92% +/- 6.1, respectively, at 2 years. Seventy-six percent of hypertensive patients benefited from the procedure. However, renal function was not improved by stent placement. CONCLUSION: Stent placement in renal arteries is a useful adjunct to percutaneous transluminal angioplasty for atherosclerotic renal-artery stenoses.

Adult↗
PubMedDate not supplied

[Infarction of the right ventricle. Contribution of two-dimensional echocardiography].

This study, based on 39 cases, confirms the value of two-dimensional echocardiography in the diagnosis of right ventricular infarction during the acute phase. This diagnosis is confirmed by the presence of abnormalities of the segmental kinetics always present in the inferior wall and less frequently in the anterior wall. The inferior part of the septum is affected in two thirds of cases. Right ventricular dilation is frequently observed, but is not constant. Two-dimensional echocardiography has a diagnostic sensitivity similar to that of isotope ventriculography, but greater than that of haemodynamic investigations. Finally, apart from the easy demonstration of complications (tricuspid incompetence, septal rupture, intracardiac thrombosis), two dimensional echocardiography can be used to evaluate right ventricular function.

Cardiomegaly↗
PubMedDate not supplied

[Value of isotopic methods in the diagnosis of myocardial infarction of the right ventricle].

In the left ventricle, isotope techniques can be used to study the perfusion of the myocardium or the ventricular function. Because of the thinness of the walls of the right heart, the classical examinations and Thallium 201 perfusion cannot be used to demonstrate a disorder of perfusion in the right ventricle. Nevertheless, it is possible, with the aid of Technetium 99m labeled pyrophosphate, to diagnose and localise necrosis of the inferior wall with an acceptable degree of sensitivity, during the acute phase of the infarction. However, the major value of isotope techniques is to evaluate right ventricular function by determining the value of the global ejection fraction and the kinetic anomalies of the different walls. These methods, together with echocardiography, allow the diagnosis of lesions of the inferior part of the right ventricle in patients with inferior necrosis... Furthermore, because these methods allow quantification and because they are reproducible and repeatable, they can be used to follow the course of the right ventricular function in response to treatment.

Evaluation Studies as Topic↗
PubMedDate not supplied

[Vectorcardiography in infarction of the right ventricle].

A vectorcardiogram (VCG) was recorded in 22 patients in the acute phase of a right ventricular infarct in order to investigate any characteristic signs of this diagnosis. The RV infarct had been proven by at least two investigations: 2D echo, isotopes and right ventricular catheterisation. 17 patients had ST depression in V4R. The QRS complex presented two features: there was a reduced refractory period in every case, associated with septal extension in 3 cases and true posterior infarction in 11 cases, and, in the frontal plane, the QRS which was in clockwise rotation had showed an abnormal left axial lead in 18 cases with a maximal vectorial axis of between - 10 degrees and - 60 degrees. These modifications are similar to those seen in experimental infarcts of the RV. In conclusion, repeated VCGs in the acute phase of inferior infarction should suggest the diagnosis of right ventricular extension if it shows the appearance of more marked left axis deviation than that seen with isolated inferior infarcts. However, this sign is no constant and is not specific.

Adult↗
PubMedDate not supplied

The idiotypic network: the murine MOPC315 anti-DNP system.

BALB/c mice were immunized against a monoclonal antiidiotypic antibody (Id 315.1.4) directed against the myeloma DNP-binding protein MOPC315 (IgA-lambda 2). This antibody is specific for an MOPC315 "private" idiotope, and the expression of this idiotope requires the interaction between MOPC315 heavy and lambda chains. Two categories of antibodies, able to combine with Id 315.1.4, were characterized in the sera of anti-Id 315.1.4 mice: (1) antibodies with a kappa light chain and without detectable anti-DNP function, and (2) antibodies with a lambda light chain and able to combine with DNP antigen. This observation suggests that the idiotypic network is not close-ended for a given idiotypic system but must be connected with other systems.

Animals↗