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J Bonal

Publications and source records attributed to J Bonal.

At least 19 recordsLinked to original sources
PubMed1998

High-performance liquid chromatography analysis of Bobel-24 in biological samples for pharmacokinetic, metabolic and tissue distribution studies.

A rapid and simple HPLC method is described for the determination of Bobel-24 (2,4,6-triiodophenol) and other iodinated derivatives in biological samples. The sample preparation was liquid-liquid extraction before injection onto the HPLC system. 2,6-Diiodo-4-methylphenol was used as internal standard. Separation was obtained using a reversed-phase column under isocratic conditions. The mobile phase consisted of water-acetonitrile (62:38). 2,4,6-Triiodophenol was detected at 277 nm. This method was used for Bobel-24 determination in plasma, urine, synovial liquid and different tissues. The assay was applied to pharmacokinetic studies in dog and horse plasma and different dog tissues for tissue distribution profiles toxicological and metabolic studies. In addition, this method for biological samples can be applied to non-biological samples such as pharmaceutical formulations in stability studies and quality control assays.

Animals↗
PubMed1997

Simple and robust high-performance liquid chromatographic method for the determination of ranitidine in microvolumes of human serum.

A simple robust high-performance liquid chromatographic method is described for the determination of ranitidine in microvolumes of human serum. The drug of interest was isolated using liquid-liquid extraction with dichloromethane and back-extraction with 0.1% phosphoric acid and separation was obtained using a reversed-phase column under isocratic conditions, with ultraviolet detection at 313 nm. Intra-day and inter-day coefficients of variation ranged from 1 to 6% and 3 to 10%, respectively. Accuracy of the assay was less than 10% at all concentrations. The limit of detection and the limit of quantitation were 2 and 7 ng/ml, respectively. The linearity was assessed in the range 10-1000 ng/ml. It was shown that a group of common drugs co-administered with ranitidine did not interfere with its determination. The applicability of this method for the pharmacokinetic study of ranitidine following i.v. infusion in patients was demonstrated using only 100 microl of serum. The ruggedness of the assay was demonstrated over a three-year period.

Anti-Ulcer Agents↗
PubMed1997

Determination of imipenem in plasma by high-performance liquid chromatography for pharmacokinetic studies in patients.

A rapid and simple HPLC method is described for the determination of imipenem in human plasma. After blood collection, plasma was separated by centrifugation and immediately stabilized with 3-morpholinopropanesulfonic acid (MOPS) and ethylene glycol solution (1:1). The sample preparation, before injection into HPLC, was ultrafiltration. The mobile phase was boric acid buffer. The imipenem was detected at 300 nm and cilastatin sodium, coadministered, did not interfere. Calibration curves in human plasma were linear from 0.1 to 100 microg/ml. The limit of detection was 0.030 microg/ml. Inter-day precision at 0.1 microg/ml, determined as the coefficient of variation, was 6.26%. Only 250 microl of plasma was required in our assay. Due to the limited stability of imipenem [G.B. Smith et al., J. Pharm. Sci., 79 (1990) 732], stability studies in plasma were done to establish appropriate storage conditions. The assay was applied to pharmacokinetic studies in patients.

Chromatography, High Pressure Liquid↗
PubMed1997

Determination of captopril in plasma by high-performance liquid chromatography for pharmacokinetic studies.

A high-performance liquid chromatographic method is described for the determination of free captopril in human plasma N-Acetyl-L-cysteine (NAC) was used as an internal standard. Plasma samples were immediately derivatized with N-(1-pyrenyl)maleimide (NPM) and stabilized with 11 M HCl. The drug of interest was isolated using a liquid-liquid extraction with ethyl acetate and separation was obtained using a reversed-phase column under isocratic conditions with fluorescence detection. The sample volume was 150 microliters plasma. The intra- and inter-day accuracy and precision, determined as relative error and coefficient of variation respectively, were less than 10%. The lower limit of quantitation, based on standards with acceptable coefficients of variation, was 25 ng/ml. No endogenous compounds were found to interfere. The linearity was assessed in the range of 25-600 ng/ml. This method has been demonstrated to be suitable for pharmacokinetic studies in humans.

Angiotensin-Converting Enzyme Inhibitors↗
PubMed1996

[Superior vena cava syndromes of benign etiology].

Superior vena cava syndromes are uncommon and usually caused by malignant diseases. In about 20% of the cases however, the cause is benign. Besides chronic mediastinitis, a growing number of cases are reported of thrombosis resulting from endovenous devices (central catheters, pacemaker leads...). Onset is often slow and insidious, good tolerance in the early stages being explained by the development of an effective collateral circulation. Bibrachial phlebography is still the reference exploration, but computed tomography and magnetic resonance imaging are contributive to diagnosis. Symptoms usually regress after medical treatment, sometimes requiring thrombolysis, however, in 10% of the patients, major functional impairment may require bypass surgery (autologous graft or endoprosthesis) or transluminal angioplasty. There is still some debate as to the precise indications for each method, but angioplasty, used recently, appears to be the most interesting technique for a disease in which prognosis is almost always favorable.

Humans↗
PubMed1996

Sudden death as a presenting symptom of hypertrophic cardiomyopathy: treatment with an implantable cardioverter defibrillator.

Aborted sudden death as the presenting manifestation of hypertrophic cardiomyopathy in a 14-year-old child is reported. Documented ventricular fibrillation was the cause of cardiac arrest. No ventricular arrhythmia was induced during programmed electrical stimulation. An implantable cardioverter-defibrillator was indicated. As the patient had a family history of myocardial disease, he had undergone a cardiovascular evaluation 4 years before the major event, and was found normal. It is suggested that normal physical examination, ECG, echocardiogram should not rule out the diagnosis of hypertrophic cardiomyopathy when a family history is present. Left ventricular hypertrophy may develop during childhood in patients with hypertrophic cardiomyopathy.

Adolescent↗
PubMed1996

[Atresia of the left coronary artery: a case in a marathon runner. Review of the literature].

The authors report the case of a very rare coronary malformation: atresia of the left main coronary artery. This anomaly was discovered in a marathon runner who presented effort angina with a positive exercise stress test. At coronary angiography, it was not possible to catheterise the left coronary artery and only a minuscle dimple could be visualised. Selective right coronary catheterisation showed a very large right coronary artery with retrograde injection of the whole of the left coronary network, as far as the left main stem. The authors did not suggest revascularisation because of the good functional tolerance of this malformation.

Adult↗
PubMed1996

[Treatment of amiodarone-induced hyperthyroidism by carbimazole with maintenance of amiodarone].

The authors report the case of a patient treated with amiodarone for syncopal ventricular tachycardia complicating idiopathic dilated cardiomyopathy in whom symptomatic hyperthyroidism led to a discussion of the different therapeutic options available in this type of case. Neomercazole treatment was prescribed with success enabling maintenance of the antiarrhythmic drug. The reputation of inefficacy of carbimazole should be reconsidered ; high dose therapy should probably be tried in patients with hyperthyroidism when withdrawal of the antiarrhythmic drug does not seem to be possible.

Amiodarone↗
PubMed1995

[Acute ischemic liver].

Ischaemic hepatitis, a condition to be distinguished from cardiac liver or stasis cirrhosis, can occur as an acute episode in patients with advanced stage congestive heart failure. The mechanism is massive necrosis in the central lobules resulting from acute hypoxia when low cardiac output reduces oxygen supply further aggravating the underlying condition of congestion due to poor venous outflow. We report 4 cases which illustrate the difficulties in diagnosis and treatment. All four patients (age range 79-86 years) were seen in an emergency situation caused by an acute drop in cardiac output aggravating their underlying heart failure. Clinical signs included jaundice, oligouria, abdominal pain and cardiovascular shock. The first element suggesting the diagnosis of ischaemic hepatitis was a sudden and massive peak in transaminase levels (> 20 times normal) which rapidly returned to normal. Prothrombin and fibrinogen levels fell rapidly and functional renal failure was present in all cases. Viral serology was negative and no hepatotoxic drugs could be incriminated. Despite symptomatic intensive care one patient died on day 15 due to cardiovascular shock. Enzyme movements, together with the lack of evidence for another cause, is the key to diagnosis of acute ischaemic hepatitis which thus is often established after the emergency situation has been controlled. Initially, viral hepatitis or drug-induced hepatotoxicity may be suspected, especially if the episode of low cardiac output goes unrecognized. Cases with signs of encephalopathy may also be difficult to distinguish from fulminating hepatitis and would be the only indication for needle biopsy in this acute situation. Outcome is generally unfavourable with mortality at 6 months estimated at 50%.

Acute Disease↗
PubMed1995

[Acute myocarditis in non-typhoid Salmonella infection].

The authors report a case of myocarditis secondary to a Salmonella Virchow infection in a 20 year old non-immunodeficient man without a previous medical history. The outcome was favourable after treatment with fluoroquinolone. The features of this rare complication of non-typhic salmonella infection are discussed with respect to this and four other recently published cases.

Acute Disease↗
PubMed1994

[Spondylodiscitis disclosing endocarditis on the endocavitary electrodes of cardiac pacemakers].

Permanent pacemaker electrode infection is rare but can be fatal. The authors report two cases presenting with spondylodiscitis, a previously described mode of presentation of valve endocarditis but not previously reported in this context. In one case, recurrent courses of antibiotics did not prevent repeated episodes of bacteraemia. In the second, the relapse of infection occurred at different sites of the vertebral column until surgical removal of the electrodes: the usual features of this pathology were observed: frequent but not constant infection at the site of the pacemaker implantation, making the diagnosis more difficult; delayed signs of spondylodiscitis after implantation of the pacemaker; recurrence of infection when antibiotic therapy alone was prescribed and, therefore, the need for surgical ablation of all implanted material. The authors underline the diagnostic value of transoesophageal echocardiography.

Aged↗
PubMed1993

[Medical phlebitis. A rational approach of the etiological evaluation].

One-hundred and four records of ambulatory deep venous thrombosis were studied retrospectively to determine the usefulness of an aetiological evaluation based on a rational approach. Among these 104 patients, 27 were known to have a cancer at the time of admission, and 77 had a presumably idiopathic deep venous thrombosis. The discovery of 10 cancers in the second group (13 percent) confirmed that the aetiological research was useful. Statistical analysis of the two populations and the different parameters of the thrombus and its course failed to show any significant difference in the patients whose cancer was revealed. The aetiological evaluation pointing to the diagnosis was always simple and not very costly; it consisted of careful physical examination with vaginal and/or rectal palpation, standard laboratory tests, X-ray films of the chest and abdomino-pelvic ultrasonography. Although these cancers were at an advanced stage when discovered, the aetiological research was justified by the finding of a few tumours amenable to curative surgical treatment.

Adult↗