The value of 2-D Doppler echocardiography in the evaluation of asymptomatic patients with Mustard operation for transposition of the great arteries

2-D Doppler echocardiography was used to assess the occurrenceof haemodynamic abnormalities in 45 asymptomatic patients, aged4 to 16 years (median 7·4) after a Mustard operationfor transposition of the great arteries. The findings were comparedwith those derived from cardiac catheterization. Thirty-fivecardiac lesions were correctly diagnosed by 2-D Doppler echocardiographyin 23 patients, but on six occasions, minor abnormalities weremissed. 2-D Doppler echocardiography demonstrated systemic venouspathway obstruction of more than 3 mmHg at cardiac catheterizationin nine patients, and in five of the six patients with pulmonaryvenous channel obstruction. A left ventricular outflow tractobstruction (pressure difference > 15 mmHg) was diagnosedcorrectly by Doppler echocardiography in seven patients. Baffleleakage was found in two patients with a left to right shuntof 25% or more of pulmonary bloodflow, but was missed in fiveout of nine patients with small shunts. Tricuspid regurgitationwas well defined in eight patients, The absence of symptomsand a routine examination after a Mustard operation do not ruleout haemodynamic abnormalities. However, these, with the possibleexception of minor baffle leakage, can be detected by 2-D Dopplerechocardiography.     

PCR-positivity in harvested bone marrow predicts relapse after transplantation with autologous purged bone marrow in children in second remission of precursor B-cell acute leukaemia

Purging of autologous bone marrow (BM) grafts of children in second remission after a relapse of precursor B acute lymphoblastic leukaemia (ALL) in the BM has been carried out in our laboratory since 1987, initially by complement mediated cell lysis. This protocol was extended by performing an immunorosette depletion before lysis with complement. The aim of the present study was to assess by polymerase chain reaction the presence of residual leukaemic cells in the BM grafts before and after purging. The results were then correlated to clinical outcome. In 24/28 patients a PCR product was obtained by amplification of IgH and/or TcR junctional regions. BM before purging was available for analysis in 13 patients. We found that leukaemic cells could be detected in 8/13 (62%) of these grafts before purging . All these eight patients experienced a relapse, regardless of whether the purging procedure had been successful (defined as achievement of PCR-negativity) or not. In contrast, none of the five patients with PCR-negative grafts before purging relapsed ( P  = 0.0008). One patient died due to transplant-related toxicity. Of the remaining 23 patients, nine patients received a PCR-positive BM graft after purging. All these nine patients experienced a relapse as compared to 6/14 whose BM was PCR-negative after purging ( P  = 0.0072). Two of eight PCR-positive BM grafts could be purged to PCR-negativity. Thus, improvements both in treatment of leukaemia and in purging efficacy are still needed.     

Modulation of Healthy Pig Coronary Arteries by Self-Expanding Stents

Objectives: To evaluate the expansion ratio of a self-expanding stem over time, and the chronic effect of stent pressure on the vessel wall . Methods: Self-expanding stents, developed by Medtronic Inc. (Minneapolis, MN, USA) and the Rouen group (Letac, Cribier, France), were implanted in 21 normal pig coronary arteries. Animals were sacrificed after recatheterization at 1 day (group I, n = 4), I week (group 2, n = 3), 3 weeks (group 3, n = 5), or 8 weeks (group 4, n = 4). Histological morphometry of the vessel medial and neointimal layers was performed. Changes were related to the, stent diameter and. its force on the vessel wall . Results: The stent expansion ratio gradually increased from 73% to 93% after 8 weeks, which implicates that radial force decreased concomitantly from 0.10 N to 0.03 N. Media compression under the rods ranged from 4l%-66% immediately after stent implantation. The mean compression was unrelated to stent expansion and remained nearly the same (40%-50%) during follow-up. Individual media rod compression ranged from 5%-95%. The neointimal layer on top of the rods increased until the third week after stent implant (neointimal thickness 211 ± 108 μm). The layer significantly decreased at 8 weeks (neointimal thickness 65 ± 9 μm). The cross-sectional neointimal area increased gradually only at the end of the stent during the 8-week follow-up . Conclusions: The self-expanding stent implanted in normal pig coronary arteries reached a gradual relaxation state 8 weeks after implantation due to the persistent radial force. This radial force induces medial wall compression, which was only positively related to the thickness of the neointimal layer at 3 weeks after implant . (J Interven Cardiol 1996;9:45–52)     

Protective immunity induced by vaccination with two Haemonchus contortus excretory secretory proteins in sheep

Two excretory secretory (ES) antigens of adult Haemonchus contortus with molecular weights of 15 and 24 kDa, respectively, were evaluated as protective immunogen against haemonchosis. Sheep were vaccinated three times and subsequently challenged with 20 000 infective larvae. Vaccination induced significant reduction (>70%) in mean faecal egg counts and abomasal worm burden compared to the non-vaccinated control group or adjuvant control group. Vaccination induced ES-specific antibodies and stimulated infiltration of mast cells in the abomasal tissue.     

Recovery from fixed–dose midazolam–induced anaesthesia and antagonism with flumazenil for outpatient arthroscopy

This study evaluated recovery after a fixed dose of midazolam as induction agent and the influence of flumazenil on recovery parameters in patients undergoing day-case surgery (arthroscopy of the knee). In 40 unpremedicated patients, anaesthesia was induced with midazolam 0.2 mg/kg, vecuronium bromide 0.1 mg/kg intravenously and 3 vol.% isoflurane in oxygen prior to intubation. Anaesthesia was maintained with nitrous oxide 66% in oxygen and 0.9 vol.% isoflurane. Ten minutes after the end of anaesthesia 20 patients received 0.2 mg flumazenil intravenously, followed by increments of 0.1 mg at 60 s intervals until eye opening. Recovery was assessed by the time to eye-opening, to answering five set questions correctly, and to recovering ocular balance (Maddox Wing test), and by comparing pre- and postoperative performance in a pencil and paper test (the p-deletion test). With the exception of ocular balance, all parameters showed a quicker improvement without side-effects in the flumazenil group. After 4 h all patients were fit for discharge. One month after the procedure, all patients were satisfied with the anaesthesia. Full recovery took on average 1.5 days (range between 0 h-10 days). Whilst the technique employing a fixed dose of midazolam as induction agent gives satisfactory intraoperative anaesthesia for day-case arthroscopy, further improvement can be made with the use of flumazenil which hastens recovery.     

Variability of crossreactivity of IgE antibodies to group I and V allergens in eight grass pollen species

Crossreactivity to Dactylis glomerata, Festuca rubra, Phleum pratense, Anthoxanthum odoratum, Secale cereale, Zea mays, and Phragmites communis of IgE antibodies against Lol p I or Lol p V was investigated by means of RAST-inhibition. Within a group of sera the degree of crossreactivity was demonstrated to be highly variable. Individual sera were not always equally crossreactive to all pollen species. A high degree of crossreactivity for Group I allergens did not necessarily implicate the same for Group V. Group I and Group V representatives were found to be present in all eight species. It was demonstrated that within this group of grass species significant quantitative and qualitative differences exist, with respect to Group I and Group V allergens. Species with a low phylogenetic affinity to Lolium perenne, like Zea mays and Phragmites communis showed a very low degree of reactivity, even when measured with the most crossreactive sera. A higher taxonomic relationship however, did not always implicate a closer antigenic resemblance. Antigenically both allergens from Zea mays are more similar to Lol p I and Lol p V, than the analogues in Secale cereale.     

Career perspectives of women and men medical students

In spite of the increasing number of women medical students, in many specialties the number of women actually working as doctors still lags behind the number of men working in the same profession. To define factors contributing to this discrepancy 646 medical students at the Vrije Universiteit in Amsterdam were surveyed. A questionnaire was used to obtain information about the difference between women and men medical students concerning their outlook on a future career as combined with domestic responsibilities. The questionnaire covered the items motives and career preference, barriers to reaching the profession of first choice, career planning and the combination of domestic responsibilities and a medical career. The results of this survey indicate that there are still important differences between women and men students in career perspectives. These differences need attention from medical students as well as teaching staff.