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31.
Prof. Dr. Bernhard Schmitt Prof. Dr. Michael Albani Priv.-Doz. Dr. Thomas Bast Prof. Dr. Ulrich Brandl Prof. Dr. Rudolf Korinthenberg Prof. Dr. Gerhard Kurlemann Prof. Dr. Bernd Neubauer Prof. Dr. Ulrich Stephani Dr. Markus Wolff 《Zeitschrift für Epileptologie》2007,20(3):113-119
Zusammenfassung
Der richtige Zeitpunkt für das Absetzen der Antiepileptika (AE) im Kindesalter ist unbekannt. Anl?sslich ihrer Jahrestagung
haben die Mitglieder des K?nigsteiner Arbeitskreises (KA) eigene und publizierte Absetzstrategien diskutiert. Da Studien zu
diesem Thema rar und widersprüchlich sind, wurde beschlossen, die Diskussionsergebnisse im Sinne einer Meinungs?u?erung zu
publizieren.
Bei Neugeborenen besteht übereinstimmung, AE innerhalb von 2 bis 12 Wochen nach dem letzten Anfall abzusetzen. Bei BNS-Epilepsie
wird Vigabatrin nach 6 bis 12 und Sultiam nach 6 bis 36 Monaten abgesetzt. Nach erfolgreicher Steroidtherapie setzt die Mehrheit
des KA die AE-Therapie für zwei Jahre fort. Für die Rolando-Epilepsie sind 1 bis 3 Jahre Anfallsfreiheit ausreichend, auch
wenn fokale Spike-Waves persistieren. Im Falle einer symptomatisch fokalen Epilepsie ist die Grunderkrankung mitentscheidend
für das Absetzen. Die Behandlung der Absencen-Epilepsie kann nach zwei Jahren beendet werden, w?hrend bei myoklonisch- astatischer
Epilepsie meist eine 2- bis 5-j?hrige Anfallsfreiheit vorausgesetzt wird. Konsens besteht darüber, dass die Juvenile- Myoklonus-Epilepsie
ein sehr hohes Rückfallrisiko birgt. Dennoch ziehen einzelne neurop?diatrische Mitglieder einen Absetzversuch nach 2- bis
3-j?hriger Anfallsfreiheit in Betracht. Die überwiegende Mehrheit des KA führt aber bei gesicherter Diagnose keinen Absetzversuch
durch. Bezüglich der Absetzgeschwindigkeit wird ein langsames (3 bis 12 Monate) Ausschleichen favorisiert. Nur zwei Mitglieder
praktizieren ein rascheres Absetzen (<3 Monaten). Das EEG spielt für die Entscheidung eine untergeordnete Rolle und bleibt
auf bestimmte Epilepsieformen (z. B. Absencen-Epilepsie) beschr?nkt.
Das vorliegende Papier gibt die Meinung des KA wieder und eignet sich nicht im Sinne einer Leitlinie. Für die Entscheidung
AE abzusetzen, ist immer eine individuelle Abw?gung von Grunderkrankung, Epilepsieform und psychosozialen Umst?nde erforderlich.
相似文献
32.
33.
Federico E Turkheimer Paul Edison Nicola Pavese Federico Roncaroli Alexander N Anderson Alexander Hammers Alexander Gerhard Rainer Hinz Yan F Tai David J Brooks 《Journal of nuclear medicine》2007,48(1):158-167
PET with [(11)C]-(R)-PK11195 is currently the modality of choice for the in vivo imaging of microglial activation in the human brain. In this work we devised a supervised clustering procedure and a new quantification methodology capable of producing binding potential (BP) estimates quantitatively comparable with those derived from plasma input with robust quantitative implementation at the pixel level. METHODS: The new methodology uses predefined kinetic classes to extract a gray matter reference tissue without specific tracer binding and devoid of spurious signals (in particular, blood pool and muscle). Kinetic classes were derived from an historical database of 12 healthy control subjects and from 3 patients with Huntington's disease. BP estimates were obtained using rank-shaping exponential spectral analysis (RS-ESA) (both plasma and reference input) and the simplified reference tissue model (SRTM). Comparison between plasma- derived BPs and those produced with the new reference methodology was performed using 6 additional healthy control subjects. Reliability of the new methodology was performed on 4 test-retest studies of patients with Alzheimer's disease. RESULTS: The new algorithm selected reference voxels in gray matter tissue avoiding regions with specific binding located, in particular, in the venous and arterial circulation. Using the new reference, BP values obtained using a plasma input and a reference input were in excellent agreement and highly correlated (r = 0.811, P < 10(-5)) when calculated with RS-ESA and less so (r = 0.507, P < 0.005) when SRTM was used. In the production of parametric maps, SRTM was used with the new reference extraction, resulting in test-retest variability (10.6%; mean ICC = 0.878) that was superior to that obtained using the previous unsupervised clustering approach (mean ICC = 0.596). CONCLUSION: Reference region modeling combined with supervised reference tissue extraction produces a robust and reproducible quantitative assessment of [(11)C]-(R)-PK11195 studies in the human brain. 相似文献
34.
Urban Sester Barbara C. Gärtner Heinrike Wilkens Bernhard Schwaab Rolf Wössner Ingrid Kindermann Matthias Girndt reas Meyerhans Nikolaus Mueller-Lantzsch Hans-Joachim Schäfers Gerhard W. Sybrecht Hans Köhler Martina Sester 《American journal of transplantation》2005,5(6):1483-1489
Patients after kidney, heart and lung transplantation differ in their immunosuppressive drug regimens and in susceptibility to infectious complications with cytomegalovirus (CMV). In this study, CMV-specific T-cell responses were characterized in long-term transplant recipients and associated with the frequency of infectious complications. CMV-reactive CD4 T cells from 50 healthy controls, 68 renal, 14 heart and 24 lung transplant recipients were flow cytometrically quantified by the induction of cytokines after specific stimulation. Moreover, the immunosuppressive effect of calcineurin inhibitors on specific T-cell reactivity was quantified in vitro and compared with responses in vivo. Median CMV-specific T-cell frequencies in long-term renal (1.48%; range 0.06-17.26%) and heart transplant recipients (0.90%; 0.13-12.49%) did not differ from controls (1.82%; 0.26-21.00%). In contrast, CMV-specific T-cell levels were significantly lower in lung transplant recipients (0.50%; <0.05-4.98%) and showed a significant correlation with the frequency of infectious episodes (r =-0.57, p = 0.005). The differences within the groups were associated with increasing dosages of immunosuppressive drugs, as exemplified for calcineurin inhibitors that dose dependently reduced specific T-cell reactivity in vitro. In conclusion, monitoring CMV-specific CD4 T cells may serve as a measure for long-term disease susceptibility and may contribute to an improved management of CMV complications after lung transplantation. 相似文献
35.
18F-FDG PET for mediastinal staging of lung cancer: which SUV threshold makes sense? 总被引:4,自引:0,他引:4
Dirk Hellwig Thomas P Graeter Dieter Ukena Andreas Groeschel Gerhard W Sybrecht Hans-Joachim Schaefers Carl-Martin Kirsch 《Journal of nuclear medicine》2007,48(11):1761-1766
(18)F-FDG PET is the most accurate noninvasive modality for staging mediastinal lymph nodes in lung cancer. Besides using visual image interpretation, some institutions use standardized uptake value (SUV) measurements in lymph nodes. Mostly, an SUV of 2.5 is used as the cutoff, but this choice was never deduced from respective studies. Receiver operating characteristic (ROC) analyses demonstrated that SUV thresholds of more than 4 resulted in the highest accuracy. But these high cutoffs imply high false-negative rates (FNRs). The aim of our evaluation was to determine an optimal SUV threshold and to compare its diagnostic performance with the results of visual interpretation. METHODS: This retrospective study included 95 patients with suspected lung cancer who underwent mediastinoscopy/mediastinal lymphadenectomy after (18)F-FDG PET (90-150 min after 250 MBq of (18)F-FDG). Maximum SUV was measured in 371 lymph node regions biopsied afterward and visually interpreted using a 6-level score (- - - through + + +). Diagnostic performance was assessed by ROC analysis. FNR and false-positive rate (FPR), the sum of both error rates (FNR + FPR), and diagnostic accuracy were plotted against a hypothetical SUV threshold to determine the optimum SUV threshold. RESULTS: SUVs in metastatic lymph nodes were higher (mean +/- SD, 7.1 +/- 4.5; range, 1.4-26.9; n = 70) than in tumor-free lymph node stations (2.4 +/- 1.7; range, 0.6-14.9; n = 301; P < 0.01). Inflammatory lymph nodes exhibited slightly increased SUVs (2.7 +/- 2.0; range, 0.8-14.9; n = 146). The plot of error rates featured a minimum of the sum FNR + FPR for an SUV of 2.5. With increasing SUV threshold, the FPR decreased most prominently up to that value whereas a continuous rise of FNR was noticed. Highest diagnostic accuracy was achieved with an SUV of 4.5. The areas under the ROC curves demonstrated that visual interpretation tends to be more accurate than SUV quantification (visual, 0.930 +/- 0.022; SUV, 0.899 +/- 0.025; P = 0.241). Using an SUV of 2.5 as the threshold, the resulting sensitivity, specificity, and negative predictive value were 89%, 84%, and 96%, respectively. CONCLUSION: For mediastinal staging, the choice of an SUV of 2.5 as the threshold is justified because FNR + FPR is minimized. The resulting high negative predictive value of 96% allows the omission of mediastinoscopy in patients with negative mediastinal findings on (18)F-FDG PET images. For the experienced observer, visual analysis should be relied on primarily, with calculation of the SUV used, at most, as a secondary aid. For the less experienced observer, the SUV may be of greater value. 相似文献
36.
Gerhard H. Schlund 《MedR Medizinrecht》2007,25(9):572
Ohne Zusammenfassung 相似文献
37.
Heinrich Schulze Mönking Wilhelm P. Hornung Karl Stricker Gerhard Buchkremer 《European archives of psychiatry and clinical neuroscience》1997,247(1):31-34
This study examines the correlation between development of expressed emotion (EE) in relatives and course of illness of 99
DSM-III schizophrenic patients. Patients whose relatives were high EE at baseline and at the 2nd CFI approximately 20 months
later had a poor prognosis at the very outset of the study and an unfavourable course of illness. They had a higher rehospitalisation
rate, more symptoms, lower psychosocial assessment, and a poorer 2-year and even 8-year outcome. Patients from families with
a fluctuating EE or a consistently low EE had better courses. Expessed emotion is therefore a valid predictor not only of
symptomatic relapses, but also of other important aspects of schizophrenia. The connection between EE index and course of
illness seerns not to be simply reactive or causal, but complex and non-uniform. 相似文献
38.
Siegfried Scherer Gerhard Herrmann Joseph Hirschberg Peter Böger 《Current genetics》1991,19(6):503-507
Summary When only plastidic features are considered, it is difficult to distinguish between monophyletic and polyphyletic xenogenous origins of plastids. We suggest that a direct comparison of nuclear and plastidic sequence-similarity pattern will help to solve this problem. The D1 amino acid sequence of six major groups of photosynthetic eukaryotes and of the two groups of photosynthetic prokaryotes are now available, including the psbA-gene product from Bumilleriopsis filiformis, which is the first molecular sequence reported for a xanthophycean alga. Evidence is provided for an independent and polyphyletic origin of plastids from five out of the six major taxa of photosynthetic eukaryotes. This conclusion is reached by comparing a plastid-based pattern of D1 similarity with a nucleus-based similarity pattern published recently. Furthermore, the availability of D1 sequences from five eukaryotic algae led to a re-evaluation of the taxonomic position of Prochlorothrix. 相似文献
39.
40.
Proximal tubular cells were loaded for 10 s with [3H]para-aminohippurate ([3H]PAH) by microperfusing the peritubular capillaries with Ringer solution containing 0.05 mmol/l PAH. Immediately thereafter
[3H]PAH influx from cells into a column of equilibrium solution injected into the oil-filled tubular lumen was measured by re-aspirating
the fluid after 1–10 s of contact time. The rise of luminal PAH concentration within 2 s of contact time was almost linear,
reaching a luminal / capillary concentation ratio of 1.6 after 2 s and of 3.2 after 5 s. The 2-s PAH concentration ratio was
not changed when different manoeuvres were applied to depolarize proximal tubular cells. Also, the 2-s PAH concentration ratio
was not influenced by varying the luminal pH from 6.0 to 8.0 or the luminal Cl–concentration from zero to 134 mmol/l or when either 5 mmol/l urate or 25 mmol/l lactate was in the luminal perfusate. A decrease
in the 2-s PAH concentration ratio, i.e. trans-inhibition, was observed when 25 or 50 mmol/l HCO3
–(–50%) was in the luminal perfusate. Trans-inhibition was also seen with 5 mmol/l of the following substituted benzoates:
2-hydroxy-benzoate (–58%), 2-methoxy-benzoate (–46%), 2-hydroxy-benzoate-acetyl ester (–36%), 2-hydroxy-3,5-dinitro-benzoate
(–48%), 3,5-dichloro-benzoate (–49%), and 2,3,5-trichloro-benzoate (–45%). No effect was seen with benzoate, 3-hydroxy-benzoate,
2-chloro-benzoate, 2-nitro-benzoate, 2,5-dinitro-benzoate, 3-sulfamoyl-benzoate and 4-sulfamoyl-benzoate. However, analogues
of the latter two compounds possessing two additional side groups, such as furosemide and piretanide, or a hydrophobic moiety,
such as probenecid, were inhibitory (by –62, –41 and –49% respectively). Phenoxyacetate had no effect; however, it inhibited
if in addition it had three chloro groups, as in 2,4,5-trichlorophenoxyacetate (–71%) or a hydrophobic carbamoyl side group,
as in mersalylic acid (salyrgan, –75%). Benzene-sulfonate trans-inhibited (–33%), as did phenolsulfonphthalein (phenol red,
–39%) and sulfofluorescein (–55%). However, the trans-inhibitory effect of the corresponding carboxy-compounds was absent
(phenolphthalein) or weaker (fluorescein, –42%). The trans-inhibitory effect of the uricosurics ethacrynic acid (–53%), tienilic
acid (–55%) indacrinone (–72%) and benzbromarone (–42%) could be attributed to two chloro or bromo side groups on the benzene
ring. Other trans-inhibiting uricosuric substances were indomethacin (–42%), sulfinpyrazone (–38%), losartan (–80%) its metabolite
EXP 3174 (–55%), and AA 193 (–65%). These organic acids, with pKa values between 2.8 and 4.9, possess chloro and sulfin groups, as well as heterocyclic 5-ring and hydrophobic ring or chain
areas. No significant effect was seen with 5 mmol/l PAH, 2-oxo-glutarate, DIDS, cGMP, prostaglandin E2, cortisol, benzylamiloride, pyrazinoic acid and 25 mmol/l lactate. Our data indicate that in situ the secretory luminal PAH
transport proceeds in a non-rheogenic fashion, per exclusionem by anion exchange. The observed trans-inhibition of PAH secretion seems to correlate with the affinity for the luminal PAH
transporter and, for uricosuric substances, with their uricosuric potency.
Received: 15 October 1996 / Received after revision: 17 December 1996 / Accepted: 18 December 1996 相似文献