On-Line Assessment (OLA) as a preparation for the European Diploma in Anaesthesiology and Intensive Care (EDAIC), a retrospective observational study on the results and the potential impact on the Part-I examination.

BACKGROUND: The EDAIC is a diploma of the European Society of Anaesthesiology and Intensive Care (ESAIC). which is obtained after passing two a written MCQ-based (Part1) and a structured oral (part2) examinationIn 2011, a formative On-Line Assessment (OLA) was introduced to help candidates to prepare for EDAIC Part1 examination (EDAIC-I). This retrospective observational study evaluated the results of the OLA and its impact on the EDAIC-1 between 2013 and 2019. METHODS: After obtaining the authorisation from the ESAIC Examinations Committee, all the results of candidates registered to OLA and/or EDAIC-I between 2013 and 2019 were included. The total number of registrations and the results were analysed and compared for both. RESULTS: Over 17,000 candidates (17,401) sat any of the written exams of the EDAIC. The overall pass-rate for the EDAIC-1 was 68.95%. The OLA score increased significantly with the number of attempts for Paper A (Basic Science) (p=0.006). Overall success of the EDAIC-I was higher in candidates who took the OLA before (72.9% versus 68.3%; OR: 1.25; 95% CI [1.12; 1.39]; p<0.001). Candidates who failed in their first attempt for EDAIC-I were more likely to sit the exam again if they had performed the OLA before (OR: 1.396, 95% CI [1.237; 1.574]; p<0.001). CONCLUSION: The OLA was associated with an improvement of the results in basic science and success rate in the EDAIC-I.

Shock metamorphism in lunar samples.

Indications of shock metamorphism produced by pressures up to the megabar region have been observed in the fine material and the breccias, but very rarely in the coarser fragments of crystalline rocks. These indications are deformation structures in plagioclase and pyroxene, diaplectic plagioclase glasses, and glasses formed by shock-induced melting of lunar rocks. Two sources of shock waves have been distinguished: primary impact of meteorites and secondary impact of crater ejecta. There are two major chemical types of shock-induced melts. The differences in chemistry may be related to impact sites in mare and highland areas.

European Diploma in Anaesthesiology and Intensive Care in Spain: Results for the part 1 and part 2 exams in the last five years. Are we going in the right direction? / Diploma Europeo en Anestesiología y Cuidados Intensivos en España: resultados de los exámenes de las partes 1 y 2 de los últimos cinco años. ¿Vamos por el buen camino?

BACKGROUND: The European Diploma in Anaesthesiology and Intensive Care (EDAIC) has become a standard of quality among Spanish anaesthesiologists. The aim of this retrospective observational study was to assess the results of Spanish participants for the Part1 and Part2 exams over a recent five years period from 2012 to 2016 and 2013 to 2017, respectively. MATERIAL AND METHODS: After obtaining the authorization from the European Society of Anaesthesiology, the results of both parts of the EDAIC exams were anonymously analysed for five years. We analysed the number of registrations, the pass rates, the cause for failure and the mean scores for basic sciences (paperA of part1 exam and the two first vivas of part2 exam) and clinical anaesthesia and intensive care (paperB of part1 exam and the two last vivas of part2 exam). Quantitative variables were analysed using the one-way analysis of variance, and qualitative variables using the chi-square test for trends. The level of statistical significance was set at P<.05. RESULTS: For the written part1 exam, 1,189 of a total of 10,954 candidates (10.85%) were registered in Spanish centres, reflecting the global growth of the exam (P=.29). The pass rate was 62.1%, with no significant differences from other countries (P=.38). Basic sciences were involved in 84.1% of failing candidates. Mean scores were 71.74±5.98% for basic science (paperA) and 74.48±4.29% for clinical anaesthesiology (paperB). Regarding the part2 exam, 72.4% of the candidates who had passed the part1 exam registered for the oral part2, with a pass rate of 62.7% versus 62.2% in the rest of the world (P=.91). Failing in the basic sciences sections of the part2 resulted in 93.8% of candidates failing the part2 exam. Bad fails were registered in 56 (31.5%) of failing candidates, of which 71.3% occurred in the basic sciences vivas. Isolated bad fails only occurred in 7 (3.9%) cases. CONCLUSIONS: The evolution of the EDAIC in Spain has been very similar to evolution of the EDAIC in the rest of the world. Further efforts to improve knowledge in basic sciences and better preparation in the technique of oral examination should improve the pass rate of the EDAIC examinations from an ever-increasing cohort of candidates.

Influence of heavy metal ions on antibodies and immune complexes investigated by dynamic light scattering and enzyme-linked immunosorbent assay.

The effect of Cd2+, Pb2+, Hg2+ and Cu2+ on the aggregation behaviour of monoclonal rat-IgG1-anti-mouse antibodies (kappa-light chain specific) and their antibody-antigen complexes with monoclonal mouse-IgG1 is reported. Investigations were done using the dynamic light scattering method. Cd2+ ions affected the hydrodynamic properties of the antibodies and the immune complex formation very little. More than 4 Cu2+ ions per antibody molecule led to large insoluble aggregates. Pb2+ ions also interacted with antibodies and immune complexes. Instead of "monomeric' antibodies (Ab) or immune complexes (Ab1Ag1), large soluble aggregates were detectable in the solution. Hg2+ ions induced complex formation with 3-4 antibodies per aggregate. Possible kinds of interaction are discussed. Additionally, we tested the antigen binding activity of metal-treated antibodies in ELISA-tests. The Sandwich ELISA technique was used to investigate the serological activity of the metal-treated antibodies, i.e., the reaction with the specific antigen. For these experiments we used the same monoclonal antibodies, mouse-IgG1 and rat-IgG1-anti-mouse. The influence of the above mentioned heavy metal ions was investigated up to a 10-fold molar excess over the antibody concentration. Even at these "unphysiological' high metal ion concentrations an inhibition of the antibody-antigen binding activity was not detectable.

Organization of human FcRII and FcRII-like (beta FcRII) genes: structural homology to HLA class I and class II genes.

Genomic EMBL 3 DNA clones representing part of the human Fc gamma receptor II and the beta Fc gamma receptor II genes were characterized. One of them contains the first five exons including the 5' flanking region of the beta FcRII gene. The signal peptide, the extracellular domains, the putative membrane spanning region, and the first amino acids of the cytoplasmic region encoded by these five exons are spread over approximately 11 kb. Another genomic DNA clone comprises four exons encoding the second extracellular domain and the transmembrane and cytoplasmic regions of the FcRII. Alignment of the genomic DNA clones reveals that these FcR genes are identically organized. Comparison of the corresponding regions of these clones shows that not only the exons are strikingly homologous but also the splice junctions and parts of the intervening sequences are conserved. Furthermore, the genomic organization of FcRII and HLA-class I resemble each other.

[Large intestinal epithelium and short-chain fatty acids. Expected, unexpected, unexplained findings]. / Dickdarmepithel und kurzkettige Fettsäuren Erwartetes, Unerwartetes, Ungeklärtes.

Short-chain fatty acids (SCFA) are present in hindgut contents in high concentrations. SCFA are generated and also absorbed rapidly in the large intestine. Absorption results from diffusion of the undissociated and lipid soluble form or in exchange for bicarbonate. The controversial concepts concerning the extent of diffusion or the exchange for bicarbonate are partly due to contradictory findings and unequal mechanisms in different species and in different segments of the large intestine as well as in the different methods used. An almost neutral pH microclimate at the luminal surface is of importance for absorption of SCFA. The apical membranes of the epithelial cells in caecum and in proximal colon of guinea pigs are an substantial barrier for the diffusion of SCFA. After withdrawal of butyrate for only one hour from the perfusion or incubation solutions a massive apoptosis had been observed during the in situ perfusion of segments of guinea pig large intestine and also in in vitro studies with isolated epithelia in Ussing-chambers. In vitro apoptotic bodies and cells are emitted at the epithelial surface. However, in vivo induced by butyrate deprivation resident macrophages were tightly clustered below the surface epithelium. Aided by cytoplasmatic projections these macrophages phagocytose and transport apoptotic material from the epithelial intercellular spaces into their bodies. Obviously macrophages can be overloaded by this massive apoptosis, and some of the undigested apoptotic fragments are emitted into the lamina propria. Formation of a colitis ulcerosa may originate from these released undigested apoptotic bodies. Furthermore hints indicate aetiological interrelations between deprivation of butyrate and colon cancer. Butyrate-paradox denotes the contrarian effects on apoptosis and cell proliferation after addition or deprivation of butyrate in cultures of large intestinal tumour-cell-lines in comparison with the healthy, intact epithelium.

Receptor binding of osteoblast-specific factor 1 (OSF-1/HB-GAM) to human osteosarcoma cells promotes cell attachment.

OSF-1/HB-GAM is a member of developmentally regulated growth factors and cytokines. High expression levels of this factor are found in different tissues, e.g., in brain and in bone. We have analyzed the biological function and binding properties of natural OSF-1 to human osteoblasts. Using antibodies raised against the entire OSF-1 molecule or a synthetic carboxy-terminal peptide (amino acids (aa) 110-140) we have investigated the binding sites of rat OSF-1 on human osteoblast-like osteosarcoma cell lines: HOS(TE85) and MG-63. Immunofluorescence microscopic studies and flow cytometric data revealed that OSF-1 is specifically bound to the surface of these cells. Further characterization of the binding sites showed that both osteosarcoma cells express two different kinds of binding sites: Besides binding to a specific OSF-1 receptor, OSF-1 also significantly binds to cell surface heparan sulfates. Using the peptide specific polyclonal antibody we show that the carboxy-terminal domain, aa 110 to 140 of OSF-1, seems to be involved in ligand binding. Studies on the biological function of OSF-1 revealed a strong cell attachment promoting activity in vitro. This activity is not diminished after digestion of cell surface heparan sulfates by heparinase I and heparitinase I, demonstrating that the OSF-1 receptor mediates the cell attachment of osteoblasts. Our results indicate that one biological function of OSF-1 is the promotion of osteoblast attachment to the extracellular bone matrix.

Endocytosis of human IgG:Fc receptor complexes by transfected BHK cells.

We have analyzed the mode of uptake of human beta FcRII molecules expressed in BHK cells (clone 2/14). When challenged with aggregated human IgG (ahIgG), these cells bind the ligand at 4 degrees C and endocytose the IgG: receptor complexes rapidly upon warming to 37 degrees C, as seen by fluorescence microscopy with antibodies directed against human IgG. Using 125I-labeled ahIgG, we found that 40% of the bound ligand was internalized within 15 min, and approximately 60% within 2 h. Surface replication and thin sectioning combined with immunogold labeling revealed that the ligand was taken up by coated vesicles and was transferred to the endosomal/lysosomal compartment. This was confirmed by confocal laser microscopy of cells double labeled for clathrin and ahIgG. After modulation of the coated vesicle pattern by hypertonic medium, ahIgG transport was impaired. These data show that a single isoform of human FcRII, expressed in an animal cell negative for Fc receptors, can use the coated vesicle based endocytic pathway of the host cell. Reincubation of cycloheximide-treated cells with a second batch of ligand showed that approximately 20% of the beta FcRII was recycled. This finding is in apparent contrast to the fate of the endogenous Fc receptors expressed on mouse macrophages.

Metabolism of the macrolide immunosuppressant, tacrolimus, by the pig gut mucosa in the Ussing chamber.

1. The macrolide tacrolimus (FK506), used as an immunosuppressant, is a cytochrome P450 (CYP) 3A substrate in the liver. The metabolism of tacrolimus and the transport of its metabolites in the pig gut was studied in the Ussing chamber. Tacrolimus and its metabolites were quantified by h.p.l.c./mass spectrometry. 2. In the Ussing chamber, demethyl, didemethyl, hydroxy and hydroxy-demethyl tacrolimus were generated. Their formation was concentration- and time-dependent. The metabolite pattern was not different from that after incubation of tacrolimus with human small intestinal microsomes. 3. The metabolite formation was highest in the duodenum and declined in the order duodenum > jejunum > ileum > colon > stomach. 4. Since tacrolimus metabolism was inhibited by the specific CYP3A inhibitors, troleandomycin and ketoconazole, we concluded that these enzymes are involved in intestinal metabolism of tacrolimus. 5. Tacrolimus metabolites re-entered the mucosa chamber (> 90%) and passed through the small intestinal preparation into the serosa chamber. 6. It is concluded that tacrolimus is metabolized in the intestine, that the metabolites are able to re-enter the gut lumen and also enter into the portal vein and that small intestinal metabolism and transport is at least in part responsible for the low oral bioavailability of tacrolimus.

Activation-dependent expression of low affinity IgG receptors Fc gamma RII(CD32) and Fc gamma RIII(CD16) in subpopulations of human T lymphocytes.

Receptors for IgG (Fc gamma R) are expressed by small subpopulations of peripheral blood T lymphocytes. Our studies demonstrate that T lymphocytes can be induced in vitro to express two different low-affinity Fc gamma R. Mitogen activation of peripheral blood T lymphocytes obtained from eight healthy individuals leads to considerable augmentation of the Fc gamma RIII+ (CD32) T cell subpopulation. The highest percentage of CD32 expressing T lymphocytes could be detected after three days of activation. The T cell subpopulation which transiently express the CD32 antigen, encompasses CD4+ and CD8+ cells. Molecular cloning of the CD32 antigen by reverse transcription and polymerase chain reaction demonstrates that activated human T lymphocytes express the Fc gamma RIIIb2 isoform. The percentage of the Fc gamma RIII+ (CD16) T cell subpopulation was significantly increased only in the lymphocyte populations obtained from three out of eight volunteers immediately after mitogen activation. However, during short-term cell culture the CD16 expressing CD8+ T cell subset increased in the T cell population from all individuals investigated. During this time, the IL-2 receptor alpha-chain (CD25) expression level decreased as a function of time. In contrast to the CD8+CD16+ T cells, the percentage of the non-MCH-restricted CD56+CD16+ T cells was not influenced by mitogen activation and time of cell cultivation. We could show that CD16 in T cells is able to mediate a stimulus leading to proliferation of the CD8+CD56-CD16+ T cells but not that of the CD56+CD16+ T cell subset. This discrepancy cannot be explained by the expression of different Fc gamma RIII isoforms, because both T cell subsets express Fc gamma RIIIA alpha, as we demonstrate in this report.

Effect of sodium nitroprusside on complement activation induced by cardiopulmonary bypass: a clinical and experimental study.

Complement activation and leukocyte stimulation were prospectively studied during and after cardiopulmonary bypass in 16 children receiving sodium nitroprusside--a nitrovasodilator releasing nitric oxide--for vasodilation during the cooling and rewarming periods of extracorporeal circulation. Results were compared with those in 29 patients who were not treated with sodium nitroprusside during the operation. Patients treated with sodium nitroprusside had significantly less C3 conversion during cardiopulmonary bypass as measured by the ratio C3d/C3 (p <0.05) and significantly less C5a liberation immediately after cardiopulmonary bypass (p < 0.005) than patients not treated with sodium nitroprusside. C4 was not overtly consumed in our series. Leukocyte count during the rewarming period of cardiopulmonary bypass, but not leukocyte elastase release during cardiopulmonary bypass, was significantly reduced in patients treated with sodium nitroprusside (p <0.05). In vitro experiments were conducted to analyze the effect of sodium nitroprusside on complement hemolytic activity initiated by the classic and the alternate pathways and on zymosan-induced C3 conversion by the activation of the alternate pathway. The in vitro experiments clearly demonstrate inhibition of complement hemolytic activity by sodium nitroprusside in the sera tested. The 50% inhibitory concentration of sodium nitroprusside on the available complement hemolytic activity was less through the alternate pathway than through the classic one (4.2 +/- 0.8 mmol/L and 14.0 +/- 2.88 mmol/L, respectively). The decrease of complement hemolytic activity measured was dose-dependent and was enhanced by the sodium nitroprusside preincubation of the sera tested. This effect was related to the duration of preincubation. Sodium nitroprusside photodegradation (enhancing nitric oxide release) increased the anticomplementary effect of the drug, reducing the 50% inhibitory concentration on complement hemolytic activity to 0.24 to 0.02 mmol/L for the alternate pathway and 2.74 o 0.3 mmol/L for the classic pathway. the zymosan-induced C3 conversion was inhibited by sodium nitroprusside. Nitroglycerin and isosorbide dinitrate (other nitric oxide donors) had in vitro effects on complement hemolytic activity similar to those of nonphotodegraded sodium nitroprusside at similar concentrations (1 mmol/L). Our results suggest that sodium nitroprusside, both in vitro and in vivo, has an inhibiting effect on complement activation initiated by both classic and alternate pathways and that this effect is mediated by nitric oxide release from sodium nitroprusside. This is the first report on the anticomplementary effect of sodium nitroprusside by nitric oxide release.

Long-term pancreatic duct occlusion impairs the entero-insular axis in the dog--failure of plasma VIP to respond as "incretin".

The response of VIP to either an oral glucose load (OGT) or intravenous glucose (IV glucose), aimed at reproducing the plasma glucose level after OGT, was studied in trained, conscious, sham-operated (Sham; n = 6) dogs, and dogs having initially (12 months before the glucose experiments) undergone occlusion of the pancreatic duct by the prolamine glue technique (Occ; n = 5). As a result, prior to glucose studies, the exocrine pancreas function was found subtotally reduced, as indirectly evaluated by the para-aminobenzoic acid (PABA) test, but no signs of diabetes were detected. The two studies with glucose administration designed to demonstrate the release of insulin, VIP, somatostatin into plasma as modified by enteric signals (represented by the difference of plasma peptide concentration during OGT minus peptide concentration during IV glucose) revealed the following: (1) basal plasma glucose, insulin, VIP, somatostatin did not differ between Sham and Occ dogs; (2) after OGT in Occ dogs the plasma glucose was elevated, whereas plasma insulin was markedly reduced, and VIP, somatostatin were largely unchanged; (3) the integrated output of insulin only was impaired when considering the so-called entero-insulin axis, while integrated VIP, somatostatin were unaltered. It was concluded (a) the Occ procedure in the dog has the capacity to subtotal destruction of the pancreatic acinar tissue, and of the entero-insular axis of insulin, the latter through yet unknown pathways, (b) the Occ technique may be a useful tool for investigation of the nature of "incretin," (c) VIP and somatostatin do not respond to elevated blood glucose and may have no role in the "incretin" concept of enteric modulation of the B-cell.

Anatomical risk factors for mortality and cardiac morbidity after arterial switch operation.

BACKGROUND: The arterial switch operation (ASO) is the treatment of choice for transposition of the great arteries. METHODS: Anatomical risk factors on mortality and morbidity were analyzed retrospectively in 312 patients who underwent ASO between 1982 and 1997. RESULTS: Survival was 95%, 92%, and 92% after 30 days, 5, and 10 years, respectively. Operative survival improved after 1990 to 97% (p < 0.001). Risk factors for operative mortality were complex anatomy (p = 0.018), coronary anomalies (p = 0.008), and prolonged bypass time (p < 0.001). Determinants of late mortality were coronary distribution (p = 0.03), position of the great arteries (p = 0.0095), bypass time (p = 0.047), and aortic coarctation (p = 0.046). After a follow-up of 3.6 +/- 2.7 years (0.1 to 14.9 years), 98% had good left ventricle function, 94% were in sinus rhythm, 2.4% had moderate to severe pulmonary stenosis, 0.3% had significant aortic regurgitation, and 1% had coronary stenosis. Freedom from reoperation was 100%, 96%, and 94% after 1, 5, and 10 years, respectively. No preoperative anatomic parameter correlated with long-term morbidity. CONCLUSIONS: ASO can be performed with low operative mortality (< 5%) and long-term morbidity. Malformations associated with complex transposition of the great arteries influence early and late mortality.

Systemic right ventricular failure after atrial switch operation: midterm results of conversion into an arterial switch.

BACKGROUND: Failure of the systemic right ventricle after atrial switch operation can be treated by conversion into an arterial switch operation. METHODS: Four patients, age 38 to 59 months, presented with right ventricular failure after Senning operation and ventricular septal defect closure. One patient had elevated left ventricular pressure; in the other three patients the left ventricle was retrained to a left ventricular/right ventricular pressure ratio of 0.8 or greater by pulmonary artery banding in 12 to 24 months. RESULTS: Postoperative course after arterial switch operation was prolonged, but clinical condition was good at discharge. Fractional shortening ranged from 20% to 28%. Trace-to-moderate aortic regurgitation was present; only 1 patient had preserved sinus rhythm. After a mean follow-up of 43.5 months 1 patient had died due to left ventricular dysfunction. The survivors are in New York Heart Association functional class I to II. Fractional shortening has improved (29% to 37%); aortic regurgitation has not increased. No patient has undisturbed sinus rhythm. CONCLUSIONS: Conversion of an atrial into an arterial switch is an alternative to cardiac transplantation in childhood. However, the procedure is demanding. Long-term morbidity is caused by rhythm disturbances. Aortic valve performance and left ventricular function require close observation.

Interleukin-2, soluble interleukin-2-receptor, neopterin, L-tryptophan and beta 2-microglobulin levels in CSF and serum of patients with relapsing-remitting or chronic-progressive multiple sclerosis.

Cerebrospinal fluid (CSF) and serum levels of interleukin-2 (IL-2), soluble IL-2 receptors (sIL-2R), neopterin, L-tryptophan (L-TRP) and beta 2-microglobulin (beta 2-M) were measured in 31 untreated multiple sclerosis patients in acute exacerbation and 27 normal controls. Twenty-six patients showed the relapsing-remitting type of disease (RRMS); 5 had a chronic-progressive course (CPMS). No changes in serum IL-2 and sIL-2R were found between RRMS patients and controls, whereas serum and CSF levels as well as the CSF/serum ratio of neopterin were significantly elevated in the RRMS group. IL-2 was not detectable in CSF of patients or controls and sIL-2R levels were at the level of the lower detection (LD) sensitivity of the ELISA method. Four of 23 RRMS patients versus 1 of 25 controls showed CSF sIL-2R levels above the LD sensitivity, indicating a trend towards elevation in acute relapse. No difference was found in serum and CSF L-TRP and beta 2-M of patients and controls. In CSF of RRMS patients neopterin and L-TRP correlated negatively, reflecting the interferon-gamma mediated activation of macrophages in acute relapse. A significant positive correlation (Spearman rank 0.57, P = 0.001) between serum IL-2 levels and duration of acute relapse (mean 30 days) warrants further evaluation.

New site for pacemaker generators in children.

Bipolar pacemaker implantation was performed in three children, aged 5, 6 and 9 years. The two epimyocardial fishhook pacing electrodes were inserted through different incisions. After resection of the anterior part of the 5th and 6th rib, the generator was placed into a pocket with the posterior wall resulting from the remaining periostium/perichondrium and the anterior wall consisting of the isolated intercostal and pectoral muscle. The leads were brought in extrapleurally and connected to the generator. The operations were conducted without perioperative and late postoperative complications.

Trial of pulmonary artery banding: a diagnostic criterion for 'one-stage' arterial switch in simple transposition of the great arteries beyond the neonatal period.

OBJECTIVE: Arterial switch operation (ASO) is the procedure of choice for the repair of simple d-transposition of the great arteries (TGA) during the neonatal period. Beyond this time such correction is performed in two stages. The first step incorporates banding of the pulmonary artery with or without a Blalock-Taussig shunt to train the left ventricle (LV). The second step consists of the ASO. To find out whether candidates for a two-stage procedure would tolerate a one-stage correction, a trial of pulmonary artery banding was performed. MATERIAL AND METHODS: Between February 1986 and December 1995, 224 patients less than 3 months of age with TGA, intact ventricular septum or a small restrictive ventricular septal defect, had an ASO. Seven patients were 4 weeks of age or older (28-70 days). Two of these had a pulmonary artery to systemic pressure ratio higher than 0.6 and underwent primary ASO without complications. The remaining five patients had low left ventricular pressure with a pulmonary to systemic pressure ratio of 0.2-0.5; echocardiography showed a banana-shaped LV with left ventricular wall thickness as low as 3 mm. They underwent a trial of pulmonary artery banding to systemic pressure for 15-30 min. As this increase in workload was tolerated well with an anticipated decrease of oxygen saturation but without hemodynamic disturbances anticipated, the ASO was performed immediately. RESULTS: Postoperative course was uneventful in all five patients, although catecholamine dependence was prolonged and three patients received enoximone. There were no severe complications. Echocardiography showed an increase in posterior wall thickness from 3 to 6 mm after 19 days in one infant. CONCLUSION: Some of the children, assigned for a 'two-stage' ASO may tolerate a primary anatomic repair up to an age of at least three months. This subgroup can be selected by a trial of pulmonary artery banding.

P300-mapping--a neurophysiological tool to quantify cerebral dysfunction after coronary artery bypass grafting.

Objective parameters are needed to quantify cerebral dysfunction following cardiac surgery in outcome and comparative studies. In this investigation we assessed the value of the late auditory evoked potentials N100 and P300 to measure the neuropsychological deficit after coronary artery bypass grafting (CABG). N100, an exogenous potential is influenced by the stimulus pattern (frequency, intensity and stimulus presentation rate). P300, an endogenous potential, depends on the cognitive processing invoked by the stimulus. With approval of the Human Investigation Committee and the patients' consents, 52 subjects undergoing elective CABG were enrolled. Operation, extracorporal circulation, anesthesia and postoperative intensive care were standardized. Twenty-channel recordings of N100 and P300 were obtained for off-line analysis. P300 was elicited using an oddball paradigm with rare target tones interspersed among frequent non-target tones. Additionally, neuropsychological tests (syndrome short test SKT and letter cancellation test) were carried out. Neurological examination and all tests were compared preoperatively and one week postoperatively. A significant deterioration in cerebral function was documented by the SKT score (P = 0.04), an increase in P300 latency (P = 0.004) and an increase of mistake rate in counting the P300 target tone (P = 0.02). No differences between preoperative and postoperative testing were found for letter cancellation, P300 amplitude and any N100 parameter. No correlation was found between the preoperative/postoperative changes in SKT score and P300 latency. P300 was proved to be an objective neurophysiological parameter that allows for the quantification of cerebral function after CABG.

Internal mammary artery bypass graft for impaired coronary perfusion after neonatal arterial switch operation.

Myocardial ischaemia caused by perfusion impairment of translocated coronary arteries is the major cause of perioperative mortality after neonatal arterial switch operation for transposition of the great arteries. We report the successful use of the right internal mammary artery as a bypass graft to a dominant right coronary artery to treat insufficient perfusion of this artery in a newborn. Eight months later, coronary angiography showed a full blood supply of the right coronary artery across the internal mammary anastomosis. After a follow-up period of more than 30 months, somatic development, electrocardiogram and echocardiographically determined contractility of both ventricles are practically normal indicating regular function of the bypass graft.

Biology of metastasizing ameloblastoma.

The present report of a malignant metastasizing ameloblastoma and a critical review of literature was undertaken in an attempt to better understand the biological potential and behavior of this rare tumor and thus to facilitate its clinical management. Most of the 26 patients with a proven malignant ameloblastoma including the present case had developed multiple recurrences. The lung was the most frequent metastatic site (88%) followed by regional lymph nodes (27%). Furthermore metastases were observed in some cases in the bone, brain, kidney, small intestine and liver. The interval between diagnosis of tumor and manifestation of metastases was long with a median of 11.1 years. The average survival time was 13.1 years. By contrast, the interval between diagnosis of metastatic disease and death was relatively short (median: 2.6 years). The histologic and cytologic pattern of malignant ameloblastoma and of its metastases was not significantly different from that of non-metastatic ameloblastoma. Because of the lack of morphological criteria of malignancy the biological behavior of ameloblastomas cannot be predicted. It is difficult to be certain which factors are important in the delayed induction of metastases. It is suspected that ameloblastomas possess an inherent low grade malignancy which is stimulated by multiple recurrences. It is further assumed that the metastatic tumor cells have a slow growth rate resulting in late clinical manifestation of metastases. When lung metastases occur we recommend their surgical removal in order to prolong live expectancy or even to obtain a curative effect.