Carotid and femoral B-mode ultrasound intima-media thickness measurements in adult post-coarctectomy patients.

AIM: Cardiovascular and cerebrovascular morbidity and mortality in adult post-coarctectomy patients is increased even after successful surgical repair of the aorta. B-mode ultrasound intima-media thickness (IMT), a validated marker for atherosclerosis and vascular disease risk, was used to measure pre-coarctatial carotid and post-coarctatial femoral arterial wall changes in these patients. METHODS: Measurements were done in 131 patients (mean age 31.6 y [SD 11.3 y]; 78 were normotensive, 53 were hypertensive) and in 26 controls (30.9 y [SD 9.4 y]). RESULTS: Age, serum lipids and smoking history were similar in patients and controls. Overall, IMT in patients and controls were similar (0.59 mm [SD 0.14 mm] and 0.59 mm [SD 0.08 mm]. In patients, carotid IMT was increased (0.67 mm [SD 0.12 mm] vs 0.61 mm [SD 0.08 mm] in controls: p=0.01); femoral IMT was decreased (0.48 mm [SD 0.09 mm] vs 0.57 mm [SD 0.07 mm]: p=0.001). In normotensive patients carotid IMT was not increased (0.64 mm [SD 0.12 mm] vs 0.61 mm [SD 0.08 mm]: p=0.2), but patients showed a higher SD. Carotid IMT in hypertensive patients was increased (0.72 mm [SD 0.12 mm] vs 0.64 mm [SD 0.11 mm] in normotensive patients: p<0.001). The femoral IMT in normo- and hypertensives patients were similar (0.48 mm [SD 0.09 mm] and 0.49 mm [SD 0.10 mm]: p=0.12). Carotid IMT in patients with aortic coarction and age at surgery were associated (r=0.36, p<0.0001), where femoral IMT is not. CONCLUSION: Early peripheral arterial wall damage is prominent in hypertensive post-coarctatial patients and is limited to pre-coarctatial conduits. The decreased femoral IMT in all patients may indicate a relatively low post-coarctatial blood pressure if pressure control is guided according to pre-coarctatial RR. Pre-coarctatial arterial wall change is less apparent in post-coarctectomy patients who have a controlled blood pressure and who had early surgical repair.     

Pharmacokinetics of piperacillin and tazobactam in critically ill patients with renal failure, treated with continuous veno-venous hemofiltration (CVVH)

Objective: Kinetics of piperacillin (pip), in combination with the beta-lactamase inhibitor tazobactam (taz) have been studied in volunteers and patients in relatively stable conditions. The fixed drug preparation appeared to have ideal pharmacokinetic properties if renal function was normal or slightly impaired, but no data are available for critically ill patients in anuric renal failure. This study should provide such data. Patients, design: We studied the pharmacokinetics in nine patients with multiple organ failure, including anuric renal failure, treated with continuous veno-venous hemofiltration (CVVH). Patients received a standard schedule of 4 g pip and 0.5 g taz administered over 0.5 h intravenously, 8 hourly. During 2 consecutive days, the serum levels of both compounds were determined, and total clearance (CI_T) was calculated from serum concentrations. Results: All nine patients completed day 1, and 8 completed day 2 of the protocol. On day 1, single-dose kinetics showed considerable spread, but pip/taz serum levels followed the pattern as expected, with a pip / taz concentration ratio of 20 : 1. On day 2, however, taz serum concentrations showed a relative increase as compared to pip, resulting in a change in the serum pip/taz concentration ratio to 10 : 1 on day 2. The CI_T of pip was 2.52 ± 1.38 l/h (t ¹/₂ : 5.9 ± 2.9 h), and CI_T of taz 4.44 ± 2.28 l/h (t ¹/₂ : 8.1 ± 3.7 h). The CI_T and t ¹/₂ of pip and taz correlated highly significantly with clearance by CVVH. Despite a higher CI_T, taz has a longer half-life, because of a higher volume of distribution. Conclusion: In CVVH dependent patients, pip/taz fixed drug preparations can be used initially, but the pip dosage should be increased relative to that of taz (or interval-adjusted) to prevent cumulation of taz, as compared to the active antimicrobial agent pip. Received: 19 February 1997 Accepted: 20 May 1997     

Sumatriptan nasal spray in the acute treatment of migraine in adolescents and children

About 4-10% of children and adolescents suffer from migraine. In the last few years, several studies have been performed to assess the efficacy and safety of triptans for the acute treatment of migraine in children and adolescents. Only sumatriptan nasal spray has been approved for the treatment of acute migraine with or without aura in adolescents aged 12-17 years in Europe. This review describes the results of the studies with sumatriptan nasal spray that have been performed in children and adolescents, including a study performed in the Netherlands.     

Temporomandibular joint arthrography following surgical treatment of internal derangements

Arthrograms of the temporomandibular joint were obtained in 20 symptomatic joints that had previous reconstructive arthroplasty with disk repositioning because of internal derangements. Preoperative arthrograms were available for comparison in 18 joints. Symptoms resulting in a postoperative arthrogram included pain, limited ability to open the mouth, and clicking of the joints. Postoperative arthrographic findings included limited anterior translation of the condyle (90%), irregularity in outline of the intraarticular contrast agent (60%), a conical configuration of the posterior recess (25%), decreased size of the joint (28%), anterior displacement of the meniscus (25%), and perforated meniscus (15%). Many of these findings may have resulted from fibrosis and scarring, which may be a response to intraarticular bleeding. The mechanism by which the fibrosis causes the postsurgical arthrographic features is discussed.     

Spontaneous remission in a patient with therapy-related myelodysplastic syndrome (t-MDS) with monosomy 7

We describe a case of spontaneously reversible refractory anaemia, a subtype of myelodysplastic syndrome (MDS), with monosomy 7 secondary to chronic treatment with azathioprine (AZA) in a young renal transplant recipient. AZA was stopped after that conventional cytogenetics and fluorescence in situ hybridization (FISH) had demonstrated the existence of a monosomy 7 clone. 4 months later, haematological values had considerably improved and the karyotypic examination as well as the FISH analysis were normal. The spontaneous remission of this MDS with monosomy 7, which is usually associated with a particularly poor prognosis, could be due to the recovery of a better immunosurveillance following the withdrawal of AZA.     

Factors influencing the likelihood of successful decisions to treat dentin caries from bitewing radiographs

The purpose of this study was to describe the role played by the ability to estimate caries depth in successfully deciding to treat dentin caries when making use of bitewing radiographs as a diagnostic test. A 10% random sample (n = 444) of Dutch dental practitioners was sent a two-wave questionnaire concerning radiographic caries diagnosis and restorative treatment decision making. The second wave consisted of simulated bitewing radiographs of 105 tooth surfaces with and without dentin caries according to two measuring standards: (a) a micro-radiographic "gold" standard and (b) a norm of expert observers. The dentists were asked to diagnose caries at 4 depths of penetration using a 5-point certainty scoring system to measure diagnostic ability; and to make a treatment decision for each surface. The overall response was 61% (273). A regression analysis was carried out using the chance per dentist of correctly deciding to treat dentin caries as the dependent variable. The degree of agreement with the experts' diagnosis of radiographic caries depth was used to create variables measuring diagnostic ability. Five significant (P less than 0.05) variables explained 60% (R2 = 0.60) of the variation in decision making. The best diagnostic ability variable explained 47% of the variation while the treatment criterion reportedly used explained 3%. We conclude that the ability of practitioners to interpret radiographs plays a major role in treatment decision making and that their reported treatment decision making criteria should not be taken at face value.     

The role of specific DNA adducts in the induction of micronuclei by N-hydroxy-2-acetylaminofluorene in rat liver in vivo

N-Hydroxy-Z-acetylaminofluorene (N-OH-AAF) was administeredi.p. to male Wistar rats 17 h after partial hepatectomy. Hepatocyteswere analyzed for the presence of micronuclei 7 h, 1, 2, 3 and4 days after injection. N-OH-AAF treatment resulted in a highfrequency of micronucleated hepatocytes at days 3 and 4 (19.5and 19.6 respectively). The frequency of micronucleated hepatocyteswas not increased above control values when hepatocytes wereisolated as early as 7 h, 1 or 2 days after injection. Pretreatmentwith the sulfotransferase inhibitor pentachlorophenol (PCP)45 min before injection of N-OH-AAF almost completely preventedthe formation of micronuclei by N-OH-AAF. Parallel biochemicalstudies indicated that inhibition of sulfation of N-OH-AAF byPCP pretreatment prevented the formation of the N-acetylatedDNA adducts iV-deoxyguanosin-8-yl-AAF and 3-deoxyguanosin-N²-yl-AAFby {small tilde}85%. Total adduct formation to DNA was, however,not lowered because of an increase in the formation of the deacetylatedadduct, N-deoxy-guanosin-8-yl-AAF. The lower frequency of micronucleatedhepatocytes observed in the group pretreated with PCP, did notresult from less proliferative activity in this group as comparedto the group treated with N-OH-AAF alone. Therefore, the decreasein the formation of micronuclei indicates that PCP preventsthe clastogenic damage caused by N-OH-AAF. It is concluded thatthe clastogenicity of N-OH-AAF in rat liver is related to theformation of N-acetylated DNA adducts (i.e. N-deoxyguanosin-8-yl-AAFand/or 3-deoxy-guanosin-N²-yl-AAF) and is not related to theformation of the deacetylated DNA adduct N-deoxyguanosin-8-yl-AF.