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Beckwith-Wiedemann syndrome is a rare congenital overgrowth disorder with macroglossia being one of the cardinal symptoms. In pronounced cases, macroglossia can lead to airway obstruction, musculoskeletal alterations and functional deficits. Surgical tongue reduction is performed at varying ages and with different techniques. This study evaluated perioperative complications, as well as long-term aesthetic and functional outcomes, in a large cohort. A total of 68 patients, treated either surgically or conservatively, were included. Depending on the severity of macroglossia, patients were divided into three groups to determine the treatment algorithm. Complications after surgical tongue reduction were prolonged intubation and revision due to dehiscence or haematoma. In the long term, no patient suffered from impaired sense of taste or paresthesia, although the shape of the tongue was disproportional in 85%. With the present treatment algorithm, operative tongue reduction exerts a positive influence on skeletal, dentoalveolar and functional development with sufficient long-term outcome and high grade of satisfaction of the patients. Supportive therapy in an interdisciplinary centre is of fundamental importance for both surgical and conservative treatment.

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The penetration of a projectile into a strongly coupled dusty plasma was studied in a radio-frequency discharge under microgravity conditions. A supersonic projectile produces an elongated dust-free cavity in its wake. The dynamics of the cavity is analyzed and compared with Langevin dynamics simulations. Besides a three-dimensional Mach cone structure, the simulation shows that the cavity dynamics can be subdivided into three phases: An opening phase with fixed time scale, a closing phase, whose duration is affected by the projectile speed and, finally, a phase of particle realignment in the target cloud, which persists for a long time after the closure of the cavity.

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Volatile anaesthetics have been shown to exert cardioprotective properties in experimental and clinical studies. However, the mode of administration may influence these cardioprotective effects. The present study was designed to compare the effect of interrupted administration of sevoflurane before cardiopulmonary bypass with continuous sevoflurane administration and with propofol-only anaesthesia, on cardioprotection as assessed by left ventricular performance and myocardial cell damage during coronary artery bypass grafting. Forty-two patients scheduled for coronary bypass surgery were randomly assigned to one of three groups: propofol-only (P; n = 14), continuous (SevoC; n = 14) and interrupted sevoflurane administration (SevoI; n = 14). Myocardial cell damage as assessed by Troponin T (cTNT) and creatine kinase MB (CK-MB) were chosen as the primary endpoints and echocardiographic myocardial performance index (MPI) measurements were also performed. Up to 48 h postoperatively, in group SevoI, postoperative cTNT values (mean (SD) 0.13 (0.04) ng x ml(-1)) were significantly (p < 0.05) lower than both the P (0.26 (0.31) ng x ml(-1)) and SevoC (0.25 (0.17) ng x ml(-1)) groups. CK-MB levels were also significantly (p < 0.05) lower in the SevoI group at 24 h after surgery and MPI significantly improved compared with both the P and SevoC groups. There was, however, no difference with respect to cytokine release and length of stay in either the intensive care unit or in the hospital. We conclude that prior interrupted sevoflurane administration confers some cardioprotection as compared with continuous sevoflurane administration or propofol-based anaesthesia.

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BACKGROUND: Minimized extracorporeal circulation is intended to reduce the negative effects associated with cardiopulmonary bypass. This prospective study was performed to evaluate whether minimized extracorporeal circulation has a clinical benefit for coronary artery surgery patients compared to standard extracorporeal circulation. METHODS: Sixty patients were randomized into two study groups: 30 patients underwent coronary artery bypass grafting using minimized extracorporeal circulation and 30 patients were operated using standard extracorporeal circulation. Baseline characteristics, intraoperative details, postoperative data, perioperative blood chemistry determinations of hematocrit, platelets, muscle-brain fraction of the creatine kinase, cardiac troponin T and colloid osmotic pressure as measurements of intrathoracic blood volume index and extravascular lung water index were compared. RESULTS: Baseline characteristics and intraoperative details of both groups were similar. Patients who underwent minimized extracorporeal circulation showed more short-term dependency on norepinephrine ( P < 0.01). Their maximal postoperative muscle-brain fraction of the creatine kinase was lower ( P < 0.05) and their hematocrit on arrival in the intensive care unit was higher ( P < 0.01). No other significant differences were found. In both collectives, values for hematocrit ( P < 0.001), platelets ( P < 0.001), colloid osmotic pressure ( P < 0.001) and intrathoracic blood volume index ( P < 0.05) decreased, while the extravascular lung water index did not change significantly during cardiopulmonary bypass. CONCLUSIONS: A clinical advantage of minimized over standard extracorporeal circulation was not found. Furthermore, a higher number of patients in the minimized extracorporeal circulation group required postoperative norepinephrine infusions for hemodynamic stabilization. In summary, the presumed superiority of minimized extracorporeal circulation for coronary artery bypass grafting in standard patients could not be confirmed.

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Plasma activity and excretion of pancreatic (P) amylase in the rat was found to be negligible. In contrast, the excretion rate of salivary (S) amylase was substantial and variable, depending on diuresis. P-amylase had a higher isoelectric point, a greater sieving coefficient, and a shorter half-life than S-amylase. A bolus injection of 125I-labelled enzymes was followed by the appearance of 125I-labelled enzyme- as well as protein-free 125I activity in the urine. The enzyme loss was smaller and the fraction of protein-free 125I activity higher following injection of P-amylase. The affinity of P-amylase to paraffin oil exceeded that of S-amylase in partition experiments with water and paraffin oil in vitro. It is concluded that both renal filtration and reabsorption of P-amylase exceed those of S-amylase. This might be due to the higher lipophility of P-amylase in comparison to the salivary type.

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Experiments were carried out in vivo on rats and in vitro on tubular brush border vesicles in order to study the renal mechanisms of the elimination of pancreatic lipase and amylase from the circulation. Highly purified 125I-labelled homologous lipase, amylase or 125I-labelled di-iodo-tyrosine was injected intravenously in a single dose. The sieving coefficients of lipase and amylase were found to be 0.126 and 0.118 respectively. Less than 1% of the lipase activity but more than 10% of the radioactivity were found in the urine in the course of a 120 min experiment. In experiments with amylase, 16% of the enzyme activity and 19% of the radioactivity were present in the urine. Elimination of both enzymes showed first order kinetics and was of the same magnitude (17-24 min). The elimination curves of the radioactivity consisted of at least two components: a fast component immediately after the injection, which was identical with the decrease of the resp. enzyme activity; and a slow component (half-life 106 min), which in both cases proved to be identical with the half-life of di-iodo-tyrosine. In experiments with amylase, the excretion of protein-free 125I-activity started later than with lipase. The radioactivity of 125I-labelled lipase was taken up faster by brush-border-vesicles than that of 125I-amylase. Liberation of protein-free 125I-activity from both enzymes occurred at the same rate. At the end of the experiments the kidneys had no lipase or amylase activity, but they contained 5.4% (lipase), 3.8% (amylase) of the injected radioactivity.(ABSTRACT TRUNCATED AT 250 WORDS)

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