Ten-years follow-up of 20 patients with idiopathic ventricular tachycardia

The follow-up and characteristics of 20 patients with ventricular tachycardia (VT) and no detectable heart disease is reported. These were 16 men and four women with a mean age of 44 years. Symptoms were present in 18 patients (eight had syncope and ten palpitations or dizziness), VT was sustained in 11 patients and a left bundle branch block morphology with inferior axis was found in 17 patients. In three patients, VT had a right bundle branch block morphology and left-axis deviation. The VT was inducible in 13 patients during the electrophysiological testing (EP) and was sustained in five patients. Medical treatment was introduced in 19 patients. During a mean follow-up of 10 years from the onset of the symptoms and 6 years from the EP testing, one patient died suddenly. He had stopped taking amiodarone 5 months before. In seven patients symptoms recurred and were due to discontinuation of therapy in two cases and inefficacy of previous effective treatment in five patients. After modification of the treatment (three cases), implantation of a pacemaker (one case) and catheter ablation (one case), all patients became asymptomatic. Eleven patients became asymptomatic with the first administered antiarrhythmic therapy. One patient continues to be asymptomatic in spite of discontinuation of his medical therapy. We conclude that patients with VT and no detectable heart disease have a good long-term prognosis and that appropriate therapy can be found in almost all patients.

Pharmacokinetics of cefotaxime in patients after liver transplantation

The pharmacokinetics of cefotaxime including formation of its active metabolite desacetyl-cefotaxime were assessed after liver transplantation in three groups of patients (four patients per group): --during the postoperative recovery phase (group 1), --during an episode of allograft nonfunction (group 2), --during an episode of allograft rejection (group 3). All patients received a single dose of 1 g cefotaxime intravenously. Concentrations of cefotaxime and its metabolite were determined in plasma and urine until 6 to 72 h after medication. The terminal half-life of cefotaxime increased and total clearance decreased due to an impairment of drug metabolism, mainly in patients with a nonfunctioning allograft and during rejection. Thus, no desacetyl-cefotaxime was detectable in urine of any patient and none in plasma of 2/4 patients with a nonfunctioning allograft. In addition, a moderate impairment of renal function in several patients contributed to the delayed elimination of cefotaxime and its metabolite. It can be concluded that liver function after transplantation is correlated with the ability to eliminate cefotaxime. Therefore, administration of half the normal dose is recommended particularly in patients with a nonfunctioning allograft or during rejection.

Potential genetic functions of tandem repeated DNA sequence blocks in the human genome are based on a highly conserved "chromatin folding code"

This review is based on a thorough description of the structure and sequence organization of tandemly organized repetitive DNA sequence families in the human genome; it is aimed at revealing the locus-specific sequence organization of tandemly repetitive sequence structures as a highly conserved DNA sequence code. These repetitive so-called "super-structures" or "higher-order" structures are able to attract specific nuclear proteins. I shall define this code therefore as a "chromatin folding code". Since locus-specific superstructures of tandemly repetitive sequence units are present not only in the chromosome centromere or telomere region but also on the arms of the chromosomes, I assume that their chromatin folding code may contribute to, or even organize, the folding pathway of the chromatin chain in the nucleus. The "chromatin folding code" is based on its specific "chromatin code", which describes the sequence dependence of the helical pathway of the DNA primary sequence (i.e., secondary structure) entrapping the histone octamers in preferential positions. There is no periodicity in the distribution of the nucleosomes along the DNA chain. The folding pathway of the nucleosomal chromatin chain is however still flexible and determined by e.g., the length of the DNA chain between the nucleosomes. The fixation and stabilization of the chromatin chain in the space of the nucleus (i.e., its "functional state") may be mediated by additionally unique DNA protein interactions that are dictated by the "chromatin folding code". The unique DNA-protein interactions around the centromeres of human chromosomes are revealed for example by their "C-banding". I wish to stress that it is not my aim to relate each block of repetitive DNA sequences to a specific "chromatin folding code", but I shall demonstrate that there is an inherent potential for tandem repeated sequence units to develop a locus-specific repetitive higher order structure; this potential may create a specific chromatin folding code whenever a selection force exists at the position of this repetitive DNA structure in the genome.

Malignant tumours in renal transplant recipients receiving cyclosporin: survey of 598 first-kidney transplantations

We analysed our population of renal transplant recipients treated with cyclosporin (CsA) and prednisolone with respect to clinically evident de novo malignancies. Eighteen of 598 patients (mean age 35.6 (1-73) years receiving their first renal graft between 1 May 1981 and 31 December 1986 developed a malignancy at a mean interval of 33.5 months. Types of malignancy were squamous carcinoma of the skin (1), carcinoma of the tonsils (1), urothelioma (5), renal-cell carcinoma (2), adenocarcinoma of colon and liver (3), metastic adenocarcinoma of the lung (1), teratocarcinoma of the testis (1), breast cancer (1), Hodgkin's lymphoma in the renal allograft (1), carcinoma of the uterus (1), and carcinoma of the prostate (1). Six cases were observed in the age group 40-49 years (3%), but only three in age group 20-29 years, and nine cases in patients older than 50 years. No malignancy emerged in children (age group less than 19 years) and in patients with pretransplant malignancies. Five patients with analgesic abuse (n = 21 of 598 patients) developed malignant urotheliomas. It is concluded that de novo malignancies constitute a heterogeneous group with no obvious risk attributable to CsA treatment. As previously reported there is a special risk of malignant urotheliomas in patients with analgesic nephropathy. The risk in children seems to be low. We did not observe the high incidence of lymphomas and skin cancer reported by other groups.

[Immediate and late complications secondary to the implantation of a coronary endoprosthesis]

The incidence of acute and late complications after coronary stenting has been studied in 95 consecutive patients. A total of 113 stents were implanted: 23 cases for acute occlusion of the dilated vessel and 72 for restenosis. After 16 months of follow-up, minor complications had occurred in 22 patients (23%). They consisted of transient occlusion of the prosthesis in 7 patients (7.3%), non-Q wave infarction in 4 patients (4.2%) and 10 hemorrhages (11%). During the following period major complications were observed in 11 patients (12%) with myocardial infarction in 7 instances and acute occlusion in 7 patients. 5 patients (5.3%) underwent coronary artery bypass graft and 6 (6.3%) died (one in-hospital death). Two deaths were related to the stent, but in the other four no definite correlation between the prosthesis and the death could be demonstrated. Restenosis at 12 months was present in 4 cases: in 3 patients (4.7%) where the stent had been implanted for restenosis and 1 (4.7%) where it had been implanted for acute occlusion. We conclude that for selected patients, coronary stenting is a promising new technique, especially for acute occlusion after PTCA; moreover, at 12 months restenosis is less frequent than after PTCA. However, technical improvement is necessary to diminish the rate of complications, particularly thrombosis and hemorrhage.

The Y chromosome of the mouse is decondensed in Sertoli cells

The condensation of the Y chromosome in mouse cells was studied with two repetitive DNA probes, pY353/B and M34. Both DNA probes are specific to the Y chromosome and hybridize in situ along the whole chromosome. Due to the high resolution of the in situ hybridization technique with non-radioactive labeled DNA probes it was possible to observe the degree of condensation of the Y chromosome in the interphase cell nuclei of various somatic tissues and on testes preparations. The Sertoli cells were the only cell type in which the Y chromosome was always observed to be in a highly decondensed state. The decondensation of the Y chromosome in the Sertoli cells supports the view that the genetic activity of the Y chromosome is cell autonomous and opens the way to its molecular analysis.

[Decrease in systemic fungal infections in hematological neoplasms with empirical use of amphotericin B therapy]

An incidence of up to 30% of systemic fungal infections at autopsy, and difficulties in diagnosing systemic mycosis antemortem, have led to the empiric use of amphotericin B in patients with hematological malignancies. Routine empiric anti-fungal treatment was initiated at our institution in 1982. Amphotericin B and initially for 3 days flucytosine was given to granulocytopenic patients with unremitting (after 48-72 h) or recurrent fever during antibiotic treatment, or with newly detected pulmonary infiltrates, sinusitis, and skin and retinal lesions suggestive of fungal infection. With this approach the rate of systemic fungal infections decreased from 10% to 4% (p less than 0.02). The reduction was most prominent in patients with acute myelogenous leukemia, where fungal infections decreased from 16% to 4% (p less than 0.025).

[Endomyocardial biopsy following heart transplantation: results and complications]

Heart transplantation (HTPL) has worldwide become a well established therapy of terminal heart failure. Besides non-invasive parameters the endomyocardial biopsy (EMB) is proved to be the goldstandard method for early detection of graft rejection. At the University Hospital of Zurich 31 HTPL have been performed between September 1985 and December 1987. 100 out of 460 EMB's showed moderate or severe rejection and needed additional immunosuppressive treatment. 1.5% of all EMB's caused further treatment due to local or systemic complications.

[Current strategy in the treatment of acute myocardial infarct]

Systemic thrombolysis significantly reduces mortality in acute myocardial infarction if the treatment is administered rapidly after the first symptoms become manifest. To optimize utilization of this new treatment, patients should be accepted for thrombolysis if they can be admitted to a hospital with intensive care units within less than three hours of first clinical signs of acute myocardial infarction evidenced by electrocardiogram. The patients should undergo coronary angiography only if chest pain or ischemic ECG changes at rest or under exercise can be documented after thrombolysis or in young patients with large infarct. If this therapeutic revolution is exploited with care and selecting the best indications, the patient will benefit from improved management.

Single versus double chamber rate responsive cardiac pacing: comparison by cardiopulmonary noninvasive exercise testing

A new double chamber rate responsive cardiac pacemaker (DDDMR) has been implanted in seven patients (four males and three females) with a mean age of 62 years. Indication for pacemaker treatment was complete AV block in two patients, complete AV block associated to sinus node disease in three patients and sinus node disease alone in two patients. Six patients underwent two maximal stress tests on a cycloergometer performed twice randomly starting with VVIMR or DDDMR. Basic work load of 50 watts was increased by steps of 25 watts every 2 minutes. Heart rate, respiratory frequency, blood pressure, exercise duration, maximal charge developed, oxygen consumption, rate pressure product, efficiency and Borg scale were compared. Our results show a general trend but no significant differences between all the measured parameters except for efficiency which was significantly higher with DDDMR. These results prove a slight improvement of cardiopulmonary performance in DDDMR pacing compared to VVIMR and also confirm the importance of atrial contribution to cardiac output on exercise.

Catheter ablation for recurrent tachyarrhythmias. Clinical experience with two different techniques of ablation in 21 patients

Between 1984 and 1988, 21 patients underwent catheter ablation for drug refractory arrhythmias. Nine patients presented atrial flutter, atrial fibrillation or atrial tachycardia, nine had supraventricular tachycardia (one AV nodal reentrant tachycardia, one reciprocating tachycardia due to concealed accessory pathway and seven WPW syndrome). Three had ventricular tachycardia. Fourteen patients were treated with direct current shock ablation (DC) and seven patients with radiofrequency ablation (RF). Eight patients underwent ablation of the His bundle. In six patients permanent AV block could be induced and in two first-degree AV block. All became asymptomatic (two with additional antiarrhythmic drug therapy). In four patients with WPW syndrome DC ablation of the accessory pathway was attempted. In one patient a permanent block in the accessory pathway and in another an intermittent block were obtained. In the two remaining patients with accessory pathways the ablation failed to interrupt the retrograde conduction: in one the retrograde conduction was modified; however, in the other no change could be demonstrated. Two patients underwent ventricular foci ablation, with one partial success (arrhythmia controlled with associated drug therapy) and one failure. Three patients had RF His bundle ablation (two for atrial flutter and one for atrial fibrillation). One complete atrioventricular block, one first degree AV block and one first degree AV block associated with right bundle branch block were induced. Recurrence of tachyarrhythmias was prevented only in the patient with complete atrioventricular block. RF ablation of accessory pathway was performed in three patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Reduction of systemic fungal infections in patients with hematological malignancies, neutropenia, and prolonged fever by early amphotericin B therapy

A rate on autopsy of up to 30% systemic fungal infections and difficulties in diagnosing systemic mycosis antemortem have led to the empiric use of amphotericin B in patients with hematological malignancies, prolonged fever, and neutropenia. Routine empiric antifungal treatment was initiated in our institution in 1982. Amphotericin B was given to granulocytopenic patients with hematological malignancies with (a) unremitting fever after 48-72 h of antibiotic treatment, (b) recurrent fever during antibiotic treatment, or (c) with newly detected pulmonary infiltrates, sinusitis, skin and retinal lesions suggestive of a fungal infection. With this approach the rate of systemic fungal infections decreased significantly from 10% (27 of 270 patients; 1973-1981) to 4% (6 of 153 patients; 1982-1986, P less than 0.02). The reduction of systemic fungal infections was most prominent in patients with acute myelogenous leukemia, where its proportion decreased from 16% (16 of 98 patients; 1973-1981) to 4% (2 of 50 patients; 1982-1986, P less than 0.023). Our data support the hypothesis that the incidence of systemic fungal infections in patients with hematological malignancies and especially in acute myelogenous leukemia can be reduced significantly by empirical treatment with amphotericin B.

Sorting of chromosomes by magnetic separation

Chromosomes were isolated from Chinese hamster x human hybrid cell lines containing four and nine human chromosomes. Human genomic DNA was biotinylated by nick translation and used to label the human chromosomes by in situ hybridization in suspension. Streptavidin was covalently coupled to the surface of magnetic beads and these were incubated with the hybridized chromosomes. The human chromosomes were bound to the magnetic beads through the strong biotin-streptavidin complex and then rapidly separated from nonlabeled Chinese hamster chromosomes by a simple permanent magnet. The hybridization was visualized by additional binding of avidin-FITC (fluorescein) to the unoccupied biotinylated human DNA bound to the human chromosomes. After magnetic separation, up to 98% of the individual chromosomes attached to magnetic beads were classified as human chromosomes by fluorescence microscopy.