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Biomedical subjects

G D'Orazio

Publications and source records attributed to G D'Orazio.

16 recordsLinked to original sources
PubMed2005

Use of vancomycin chiral stationary phase for the enantiomeric resolution of basic and acidic compounds by nano-liquid chromatography.

In this paper we studied the potentiality of nano-liquid chromatography (nano-LC) for the enantiomeric resolution of both basic and acidic compounds of pharmaceutical interest using a vancomycin modified silica stationary phase. Experiments were carried out in a fused silica capillary of 75 microm I.D. packed with chiral modified silica particles of 5 microm diameter, the detection, was done on-line at 195 nm. Enantiomeric resolution of alprenolol, atenolol, metoprolol, oxprenolol, pindolol, propranolol (basic compounds) and some acidic analytes, namely 2-[(5'-benzoyl-2'-hydroxy)phenyl]propionic acid (DF1738Y), 2-[(4'-benzoyloxy-2'-hydroxy)phenyl]propionic acid (DF1770Y), ketoprofen, indoprofen and suprofen was studied by nano-LC utilizing mobile phases containing methanol-acetonitrile-ammonium formate or acetate. The effect of mobile phase composition (buffer type and concentration, organic modifier type and concentration) on chiral resolution (Rs), retention factor (k) and retention time (tR) was also investigated. Good enantiomeric resolution was achieved for basic compounds utilizing the mobile phase containing 90% (MeCN-MeOH)/5% water/5% of 100 mM ammonium acetate pH 4.5. Acidic compounds such as DF1738Y and DF1770Y were better resolved at lower pH 3.5 while ketoprofen, indoprofen and suprofen exhibited the highest resolution at pH 4.5; in this case the mobile phase contained MeOH or MeCN (90%), 5% buffer and 5% of water. The nano-LC method was validated using R-(+)-propranolol as an internal standard finding good repeatability, detection limit, correlation coefficient and recovery and applied to the assay of a pharmaceutical formulation containing a racemic mixture of metoprolol.

Adrenergic beta-Antagonists↗
PubMed1990

[Idiopathic restrictive cardiomyopathy. Description of 4 cases].

The clinical and instrumental characteristics of four patients suffering from idiopathic restrictive cardiomyopathy are analysed. Patients were diagnosed following hemodynamic and histological tests. The major clinical symptom was cardiac decompensation and/or hyperkinetic or hypokinetic (3rd degree BAV) supraventricular arrhythmia (atrial fibrillation). Electrocardiographic and radiological alterations were not specific. The most typical echocardiographic symptom was the association of: biatrial dilation, dilation and hypertrophy of the right ventricle, normal left ventricular size, normal fractional shortening of the left ventricle. Septal hypertrophy was also observed in one case. Abundant pericardial effusion was present in all cases. When performed, echo-Doppler showed a relatively typical shortened deceleration time through the A-V valve. Catheterism revealed increased ventricular telediastolic pressures and a bi-plateau morphology of the ventricular pressure curve. Heart index was depressed in one patient and the ejection fraction was reduced in one case. Histological tests revealed interstitial fibrosis, cellular hypertrophy and, in one patient, myocardial amyloidosis. One patient underwent a heart transplant, two patients died while waiting for a transplant, one patient is still alive 13 years after the start of 3rd class symptoms.

Adult↗
PubMed1983

[Comparison between one and two dimensional echocardiography in the study of segmentary kinetics of the left ventricle in post-infarct ischemic myocardiopathy].

Sixty two-dimensional M-mode echocardiograms of myocardial infarction patients, performed 3--6 months after acute attack, were compared with those of 30 normal subjects. In one-dimensional echocardiograms, the dimensions of the left ventricle and some segmentary signs of contractility such as diastolic thickness, excursion and systolic thickening of the septum and the posterior wall of the left ventricle were examined, in two-dimensional echocardiograms the contractility of single areas was compared to those adjacent. In heart attack patients parameters studied were changed in a statistically significant way (p less than 0,001); the degree of correlation between the site of hypo-akinesis and the ECG necrosis site was quite high; compensatory hyperkinesia was frequently found in the area diametrically opposite to dyskinetic areas. The two-dimensional examination was also very sensitive especially in the diagnosis of aneurysm, which is sometimes not noted in M-mode.

Cardiomyopathies↗
PubMed1982

[Pathogenetic interpretation of left ventricle obstruction in hypertrophic obstructive myocardiopathy].

Nine patients affected from IHSS have been studied by 2D-echocardiography examination. Following detected pictures the Authors try to explain the pathogenesis of the dynamic obstruction of the L.V. The Authors conclude ascribing it to the postero-medial papillary muscle that move abnormally towards the IVS. Instead the SAM could be ascribed to the chordee of the mitral value, but these are considered unable to obstruct L.V. The differences between SAM and L.V. obstruction are underlined and discussed.

Cardiomegaly↗
PubMed1982

[Clinical evaluation of the therapeutic effect of D-L-carnitine in the acute phase of myocardial infarct in relation to the behavior of the serum myoglobin concentration curve].

Clinical experience carried out on 40 patients with AMI - 22 of them treated with 15 g daily of D-L-Carnitine and 18 untreated - is reported. Our interest was to study the therapeutic action of this drug evaluating if it was able to modify the curve of serum myoglobin level released from necrotic or ischaemic areas. The conclusion is drawn that this drug could act feebly only during the earlier stages of AMI, but many reserves are expressed.

Aged↗
PubMed1982

[Paradoxical movement of the interventricular septum and LAE in a case of complex congenital cardiopathy in an adult with predominant overloading of the right ventricle pressure].

A casually observed case of complex congenital cardiopathy in an adult marked by ECG LAE, and paradoxical movement of the interventricular septum when examined echocardiographically is reported. Haemodynamic investigation established the persistence of a left vena cava superiore draining into the coronary sinus, pulmonary stenosis with a 55 mmHg transvalvular gradient, and a small PDA with left-to-right shunt equal to 20% of the pulmonary capacity. The case is presented on account of the infrequent association of these defects, the unusual ECG LAE, and above all on account of the echocardiographic picture of paradoxical movement of the IVS in the presence of right ventricle overloading.

Adult↗
PubMed1982

Hemodynamic changes induced by supraventricular tachycardia.

In nine patients (pts.) with recurrent SVT, we have performed a combined electrophysiological and hemodynamic study. Five pts. showed reciprocating nodal tachycardia and 4 pts. reentry tachycardia associated with WPW syndrome (2 with Kent bypass tract and 2 with James bypass tract). Hemodynamic parameters were recorded during sinus rhythm (SR), atrial (AP) and ventricular pacing (VP) and following the initiation of SVT. The arrhythmia was induced by rapid atrial pacing or with atrial or ventricular premature stimuli. Hemodynamic data were then compared. Our results point out a greater hemodynamic deterioration during SVT than during AP or sinus tachycardia at similar rates. We have often observed in SVT, and constantly in A-V nodal reentrant (AVN) cases, the appearance of giant waves in the right and left atrium. This finding confirms hypothesis of the primary role of the changes in atrioventricular contraction sequence during SVT, especially in AVN tachycardias, with subsequent reduction in stroke volume and cardiac output.

Adolescent↗
PubMed1978

[Lithium in the prevention of manic-depressive and schizo-affective psychoses].

The brilliant results obtained with lithium carbonate in the prophylactic treatment of manic-depressive (MDP) and schizoaffective (SAP) psychoses over almost five years are reported. The series includes 53 patients, 46 of them suffering from MDP and 7 from SAP. In the majority of cases, the lithium dose used was 900 mg/die and lithaemia was 0.564 +/- 0.0632 mEq/1. The parameters considered were the number of attacks, their intensity and duration; therapy, if any, with traditional psychodrugs (neuroleptics and antidepressants); the number of hospitalizations and their duration. Results were valuated by comparing an equal period of time before and during therapy with lithium. In MDP the number of attacks fell 74.25% and their duration by 83.14%; severe attacks responded better to treatment, with a reduction of 94%. The quantity of traditional psychodrugs used was reduced by 66.42%. The number of hospitalizations fell 75% and days admitted by 80%. In SAP the results were even better: the number of attacks fell by 87.5% and their duration by 94.7%; serious attacks disappeared completely and the quantity of traditional psychodrugs used fell by 57.06%. The number of admittances fell 75% and days in hospital by 97%.

Adult↗