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It is shown how single and two particle properties enter the equation of state of dense plasmas. Results are given for weakly nonideal plasmas which are of interest for helioseismology and inertial fusion.

Das kolorektale Karzinom ist mit einer Inzidenz von 73.000/Jahr die häufigste in der deutschen Bevölkerung auftretende Tumorentität. Deutschland hat als eines von wenigen Ländern der Welt ein umfassendes Vorsor-geprogramm, das leider immer noch viel zu wenig in Anspruch genommen wird. Die Prognose des kolorek-talen Karzinoms ist entscheidend abhängig von der primären Tumorausdehnung bei der Diagnose und der biologischen Aggressivität der Tumorzellen. Der Beitrag bietet einen Überblick zum aktuellen Vorgehen bei der Früherkennung des kolorektalen Karzinoms.

Gastrointestinale Nebenwirkungen beeinträchtigen in erheblicher Weise die Lebensqualität von Tumor+patienten und gehören zu den häufigsten Nebenwirkungen einer zytostatischen Chemotherapie. Sie sind nicht selten dosislimitierend und führen zu Therapieverzögerung oder gar -abbruch. Prophylaxe und Therapie gastrointestinaler Nebenwirkungen stellen daher eine besondere Herausforderung für jeden onkologisch tätigen Arzt dar und setzen die Kenntnis der spezifischen Zytostatikaeigenschaften voraus. Zu den wichtigsten gastrointestinalen Nebenwirkungen gehören Appetitlosigkeit, Nausea, Emesis, Mukositis, Diarrhö und seltener die Obstipation. Gastrointestinale Nebenwirkungen gehören zu den häufigsten und für die Patienten am stärksten belastenden Nebenwirkungen einer zytostatischen Chemotherapie. In den letzten Jahren hat die Wissenschaft wichtige Fortschritte beim Verständnis der Pathophysiologie dieser Nebenwirkungen gemacht. In Bezug auf Nausea und Emesis haben die Erkenntnisse zur Entwicklung neuer Substanzen wie den 5-HT3-Antagonisten und den NK1-Rezeptorantagonisten (Aprepitant) geführt, mit denen bei leitliniengemäßer Anwendung das Erbrechen auch bei hoch emetogenen zytostatischen Therapien in der Regel gut beherrschbar ist. Im Bereich der oralen und gastrointestinalen Mukositis ist der therapeutische Nihilismus inzwischen einer wissenschaftlichen Auseinandersetzung mit diesem Problem gewichen. Mit der Verfügbarkeit des Keratinozyten-Wachstumsfaktors-1 (Palifermin) ist bei therapiebedingter oraler Mukositis erstmals eine kausale Behandlung möglich. Für die Prophylaxe und Therapie der wichtigsten gastrointestinalen Nebenwirkungen stehen aktuelle Leitlinien zur Verfügung.

Abstract: Background: Argon plasma coagulation (APC) is a thermal coagulation technique that uses ionized argon for contact-free transmission of high-frequency electrical current to tissue. Prospective data on complications with the new APC-2 (VIO) system are lacking. Methods: A prospective trial was conducted with 152 patients treated for various gastrointestinal diseases using three modes of the APC-2. The study aimed to assess complications, focusing on the pain and neuromuscular stimulation (NMS) experienced during and after treatment. Patients reported pain and NMS using a scale ranging from 0 to 10 and were interviewed for symptoms such as tingling, paresthesia, muscle pain, and cramping or twitching. The endoscopists also graded NMS using a separate questionnaire. Results: A total of 85 males and 67 females (median age, 66 years) were enrolled in the study. All APC therapies were completed successfully. Two peri-interventional perforations were recorded. Of the 152 patients, 26 (17%) reported pain sensation during or after APC. The median pain sensation reported by the patients on the standardized scale was 3.7. The findings showed NMS in 14 (9.2%) of the 152 patients. Significantly more NMS events were seen with pulsed APC than with forced or precise APC. Additional risk factors for NMS were gender (female) and type of sedation (combination midazolam and pethidine). No complications were noted among patients with intracardiac defibrillators or cardiac pacemakers. Conclusions: According to the findings, APC may be associated with minor complications such as pain sensation and NMS. These complications were rarely seen, but occurred more often with pulsed APC than with forced or precise APC. Physicians should be aware of these complications.

Copyright of Acta Endoscopica is the property of Lavoisier and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Tant chez l’homme que chez la femme, le cancer colorectal (CCR) constitue la deuxième cause de décès dans les pays occidentaux. Par conséquent, le dépistage du cancer colorectal et de ses précurseurs est un important problème de santé publique. L’utilisation de la coloscopie par tomodensitométrie computée (CTDM) et par résonance magnétique (CRM), mieux connue sous l’appellation coloscopie virtuelle, rencontre un succès populaire croissant. Le présent article a pour but de passer en revue les données de la littérature, d’établir l’état actuel de la coloscopie virtuelle, et de prédire son impact potentiel sur la pratique actuelle et future en gastro-entérologie. En résumé, la coloscopie virtuelle, spécialement celle pratiquée par coloscopie en TDM est hautement spécifique, mais sa sensibilité est très variable. Cette hétérogénéité s’accroît en fonction de la cohérence du procédé et de la variabilité des moyens techniques. Ces problèmes doivent être résolus avant que la coloscopie virtuelle puisse être proposée comme une méthode généralisée de dépistage du cancer colorectal. Colorectal cancer (CRC) is the second leading cause of cancer death for both women and men in western countries. Thus screening for colorectal cancer and its precursors is an important public health issue. Increasing popular screening tests for colorectal cancer are computed tomographic (CT) colonography and magnetic resonance (MR) colonography, also known as virtual colonoscopy. In this article we reviewed the literature to assess the current state of the art of virtual colonoscopy and to predict the potential impact on the current and future practice in gastroenterology. In summary virtual colonoscopy, especially computed tomographic colonography is highly specific, but the range of reported sensitivities is wide. This heterogeneity raises concerns about consistency of performance and about technical variability. These issues must be resolved before virtual colonoscopy can be advocated for generalized screening for colorectal cancer. [ABSTRACT FROM AUTHOR]

Extracorporeal shock wave lithotripsy (ESWL) is effective in the treatment of symptomatic cholecystolithiasis in well-selected patients. We analyzed the predictors of cholecystectomy in a large series of gallstone patients after ESWL. This was a retrospective follow-up cohort-study of consecutive patients undergoing ESWL for symptomatic cholecystolithiasis over a 9-year period. It was possible to analyze a total of 297 patients; there were 211 women and 86 men, with a mean age of 52 years (range, 8–81 years). Patients that had been cholecystectomized after ESWL were compared to patients with their gallbladder still in situ and determinants of cholecystemctomy in terms of clinical, stone, and gallbladder parameters and symptoms analyzed. The mean duration of follow-up was 99 months (range, 27–134 months). During follow-up, 106 (36%) patients underwent a cholecystectomy at a mean of 34 months (range, 0–127 months) after ESWL. Histological data showed a normal gallbladder wall in only 4 cases; 101 examinations revealed some kind of (chronic) inflammation, which was not different from histological gallbladder results in patients without prior lithotripsy. Three gallbladder polyps were found, but no carcinoma. Cholecystectomy after ESWL of gallbladder stones was strongly associated with persitent and/or renewed biliary symtoms. Nevertheless, only three of four patients became asymptomatic after CE. Thus, ESWL proved to be a valuable organ-preserving alternative to cholecystectomy in selected patients.

Copyright of Acta Endoscopica is the property of Lavoisier and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The next generation of experiments - both for tokamaks and stellarators - requires the development of appropriate theoretical models. One important aspect here is the plasma edge physics description. Fluid transport codes extending beyond the standard 2-D code packages like B2-Eirene or UEDGE are under development. In the case of tokamaks, an interesting alternative line is the concept of an ergodic edge (necessary e.g. for ergodic divertors in TORE SUPRA or TEXTOR-94) creating a 3-D edge structure. To study these effects, a 3-D code E3D based upon a Multiple Coordinate Systems Approach is being developed. Presently, we are extending the program towards stellarator applications. A few new options are made available: single-island geometry and new formulation of boundary conditions. For the new stellarator W7-X, a 3-D finite volume code BoRiS is being developed using magnetic (Boozer) coordinates. In this paper, we present a benchmark of both codes, for a test geometry (one single magnetic island in W7-X) including full 3-D metric variations, solving for the strongly anisotropic electron heat conduction equation.

BACKGROUND: There have been conflicting reports as to whether pancreatic ductal drainage achieved by endoscopy and lithotripsy improves the clinical outcome of patients with chronic pancreatitis. AIMS: To determine the clinical outcome in patients with chronic pancreatitis who received extracorporeal shock wave lithotripsy (ESWL), and were followed up for two to eight years. METHODS: Eighty patients with severe chronic pancreatitis and endoscopically unretrievable obstructive stones underwent ESWL with a piezoelectric lithotripter between 1989 and 1996. Clinical status, relief of symptoms, further endoscopic or surgical interventions, and mortality were defined. RESULTS: Forty three (54%) patients were treated successfully with ESWL. The only feature associated with treatment success was the presence of a single stone rather than multiple stones. Successfully treated patients tended to experience less pain, although this did not reach statistical significance. A slight increase in weight was noted in our patients; however, there was no notable improvement in anomalous stools and diabetes mellitus. Five patients died due to extrapancreatic reasons. No pancreatic carcinomas developed. CONCLUSIONS: ESWL associated with endoscopic drainage is a safe technique that is particularly successful in patients with a single stone. However, pancreatic drainage by endoscopy and ESWL has almost no effect on pain in chronic pancreatitis. Furthermore, endoscopic management and ESWL does not prevent or postpone the development of glandular insufficiency.

Summary Whipple's disease is a curious disorder with the involvement of many organ systems, primarily gut, synovium and the central nervous system, characterized by the presence of numerous proliferating bacteria in tissue macrophages and other cell types. While clinically this disease entity has previously been defined by the classical triad of diarrhoea, malabsorption and weight loss, some patients do not show these features. In this report, a clinically unusual case of Whipple's disease is described presenting with high persistent fever, severe arthralgias and headaches, but without malabsorption, diarrhoea or weight loss. Nevertheless, the histological and electron microscopical pictures demonstrated the typical findings of intracellular micro-organisms along with the presence of bacteria in Schwann nerve cells, which has only once been described previously. Immunological findings before treatment demonstrated a decrease of T cells with the helper/inducer phenotype, and a concomitant rise in cells with the suppressor/cytotoxic phenotype, an elevation of “activated” Ia positive T cells and a significant reduction of T cell mitogenic responsiveness. Of special interest, after a successful treatment these immunological abnormalities shifted to normal with the exception of a still elevated number of Ia+ T cells. The discussion of this unusual case of Whipple's disease includes — besides possible cellular immunological abnormalities — genetic factors, especially since this patient was HLA-B-27-positive as was his son who is suffering from ankylosing spondylitis.

Monolayer tissue culture cells from benign nodular hyperplasia of the prostate transferred at 1–2 weeks intervals were examined under the electron microscope after the 3rd, 9th, and 10th transfers. Changes seen after 9 to 10 transfers were interpreted as an “aging process” and consisted of the presence of lysosomes of various types and variations in the mitochondria profile. These changes were described in detail and illustrated and compared to the ultrastructural appearance of monolayer cell cultures in the early transfer stage.

Between January and May 1989, 65 patients with symptomatic gallbladder stones were treated with extracorporeal piezoelectric lithotripsy (EPL) and supplementary dissolution therapy with oral bile acids. In 98 of the patients, fragmentation of stones was achieved. On average, each patient received 3.18 treatments. In addition to attacks of colic and asymptomatic changes in laboratory parameters, one hematoma of the gallbladder and one of the liver were observed, together with pancreatitis and cholecystitis in two patients each. During the follow-up period, three patients developed symptomatic bile duct stones. An endoscopic retrograde cholangiopancreatography (ERCP) with papillotomy was performed on four occasions, while one female patient had to undergo urgent cholecystectomy for inflammation of the gallbladder and empyema. Six months after the initial treatment, 36 (55) patients were free of stones, while the stone-free rate after 12 months was 64.5 (41 of 65). Ninety percent of the patients with a solitary stone ≤2 cm in diameter became stonefree within a year. Extracorporeal piezoelectric lithotripsy is clearly a feasible procedure for the treatment of certain gallstone patients.

With the aim of identifying the criteria that have a decisive influence on the success of treatment of gallstones with ESWL and oral dissolution therapy, we investigated, in 117 patients, the stone-free rate as a function of sex, age, weight quotient, number of stones, total stone volume, and gallbladder function. The following inclusion criteria were applied: (1) the Munich criteria, (2) a follow-up period of at least 12 months, or (3) freedom from stones irrespective of the duration of the period of follow-up. Although, owing to the small number of cases involved, no significantly differing results were seen in the parameters investigated, clear tendencies were indeed observed. While age, sex, and weight quotient qppear to have no influence on the stone-free rate, the number of stones, total stone volume, and gallbladder function do appear to have an effect on the results of treatment. Patients with solitary stones not more than 20 mm in diameter, and patients with a small total stone volume and good gallbladder function would appear to have the best chance of becoming stone-free within a short period of time, irrespective of age, sex, or girth.

Intracorporeal shockwave lithotripsy was performed in 36 patients with problematic common bile duct stones. All of the patients had undergone unsuccessful mechanical lithotripsy prior to this procedure. In 29 patients (80.6%), the stones were fragmented under cholangioscopic control and subsequently extracted with a Dormia basket. In seven patients, the procedure failed due to stone impaction or failure to intubate the common bile duct with a nasobiliary tube. No complications were observed. Cholangioscopically guided intracorporeal shockwave lithotripsy is a highly effective and safe procedure for the conservative treatment of complicated common bile duct stones.

In this prospective study of 80 patients with active bleeding from the gastrointestinal tract a Doppler ultrasonographic investigation of the gastroduodenal ulcers was performed, in addition to immediate endoscopic examination. Admitted to this study were ulcers with the stigmata of acute bleeding, such as a visible blood vessel in the ulcer floor, a blood clot, or a black base and Forrest III lesions. In 52 patients Doppler ultrasonography was able to document unequivocally a superficial blood vessel. Complete agreement of endoscopic and Dopper results was obtained in only 49% of the cases. When a blood vessel was positively identified, local injection of epinephrine and polidocanol was carried out. There upon, in the further course, the acoustic signal was shifted into deeper regions or disappeared entirely. In 8% of the cases initial sclerosing was followed by a rebleed, which was again treated by injection therapy. None of the patients died of their GI hemorrhage. Endoscopic Doppler ultrasonography is a new and effective procedure that enables objectification of the endoscopic findings. It identifies the indication for proceeding to operative endoscopy and can monitor the effectiveness of the latter.

Therapeutic endoscopy in the esophagus has become a common procedure for a variety of clinical conditions. Peptic disorders of the esophagus especially deserve a consequent bougienage with various types of bougies. Interest has focused on the development of improved bougienage devices that could be tested with conventional techniques. Laser application is now a routine procedure in the palliative relief of upper gastrointestinal obstruction. Major questions concern the final outcome of patients in this particular situation; interesting developments concerning new light-delivery systems or the influence of photodynamic therapy are of growing significance. Finally, a few peculiar case reports underline the therapeutic possibilities that are a result of advanced endoscopy in esophageal disorders.

Zusammenfassung: Palliative endoskopische Interventionen knnen heute mit groem Erfolg zur Verbesserung der Lebensqualitt der individuellen Patienten eingesetzt werden. Die Laservaporisation von malignen sophagusstenosen fhrt in ber 80% der Flle zu einer raschen Passagewiederherstellung. Die Komplikationsrate der Methode ist uerst gering. In Abhngigkeit vom Dysphagiegrad lt sich im Einzelfall damit auch die berlebenszeit verlngern. Nachteile des Lasers sind hufige Wiederholungen, die durch ein nur relativ kurzes dysphagiefreies Intervall hervorgerufen sind. Die Tubusimplantation ist eine zuverlssige Behandlungsmanahme, deren Nachteil allerdings in einer relativ hohen Komplikationsrate liegt. Perforation und Dislokation sind gefrchtet. Die Kombination aus Laser und Tubus bringt keinen entscheidenden Vorteil. Die individuelle Situation des Patienten entscheidet im Einzelfall ber die Anwendung der Methoden.

Adamek HE, Buttmann A, Weber J, Riemann JF. Can aspirin prevent gallstone recurrence after successful extracorporeal Shockwave lithotripsy? Scand J Gastroenterol 1994;29:355-359.Extracorporeal Shockwave lithotripsy (ESWL) is a feasible procedure for the treatment of gallbladder stones in humans. Well-selected patients can achieve stone-free rates in a high percentage. With the gallbladder in situ, these patients are at risk of stone recurrence. There is considerable evidence that aspirin prevents cholesterol gallstone formation in animal models and may prevent gallstone recurrence in man. We attempted to clarify the risk of gallstone recurrence after successful piezoelectric lithotripsy in patients taking either low-dose aspirin or no medication. The first 45 patients shown to be completely free from stones after ESWL were randomized into two groups. One group 100 mg aspirin daily; the other group did not receive any further medical therapy. Patients were further examined on an average of 19.6 months and 21.9 months, respectively. In the aspirin group the recurrence rate was 18.2%, whereas 21.7% of the patients in the control group developed recurrent stones. Seventy-eight per cent of these patients also had a recurrence of biliary pain. By life-table analysis we had, after a follow-up period of 24 months, a stone recurrence rate of 25% (±11) in the aspirin group and 34% (±14) in the control group. Our results indicate that recurrence prophylaxis remains one of the central questions in ESWL. In this preliminary study, 100 mg of aspirin daily was not able to reduce the recurrence rate after successful ESWL. Further studies will have to show whether higher doses of aspirin or other ways of preventing gallstone after ESWL are possible.

BACKGROUND: The value of magnetic resonance cholangiopancreatography (MRCP) is under debate. AIMS: To assess the diagnostic accuracy of MRCP and endoscopic retrograde cholangiopancreatography (ERCP) and to determine whether MRCP may help to prevent unnecessary interventional procedures. METHODS: Eighty six patients with suspected common bile duct obstruction who presented between January and December 1996 were enrolled. Twenty six were excluded due to anatomical reasons or because MRCP or ERCP could not be performed successfully. Results of MRCP were interpreted by two radiologists and a gastroenterologist unaware of clinical diagnosis. Final diagnosis was determined by ERCP and histopathological findings or a follow up of at least 12 months. RESULTS: MRCP images of diagnostic quality were obtained in all 60 patients. Thirteen patients had a clear bile duct. Sensitivity and specificity for the detection of any abnormality (n=47) were 89% and 92%, and for the detection of malignancy (n=27) 81% and 100%, respectively. These results were equivalent to the respective figures of ERCP (91% and 92% for any abnormality, and 93% and 94% for malignant diseases). CONCLUSIONS: MRCP is as sensitive as ERCP in the evaluation of bilary tract diseases. As the specificity of this non-invasive technique is close to 100%, MRCP may prevent inappropriate invasive explorations of the common bile duct and pancreatic duct.

Ultrastructural studies of colonic biopsies from patients with a history of long-term laxative abuse, predominantly with stimulant cathartics such as anthraquinone derivatives or bisacodyl, indicated that submucosal nerve fibres may be severely damaged in relation to dosage and time of addiction. The main pathological features found were ballooning of axons, reduction of nerve-specific cell organelles, lysosomal activity, and increase of melanin-loaded macrophages. Morphometric analysis revealed a significant increase (P<0.01) in axonal area, with simultaneous reduction of neurotubules. Nerve endings showed a significant decrease of neurosecretory granules when compared with those of normals. It is concluded that these alterations might be a morphological correlation to the clinically evident disturbance of gut motility in patients with chronic laxative abuse, because the intact enteric plexus system is a prerequisite for coordination of normal gut peristalsis.

Background: Esophageal perforation is one of the most dreaded complications in therapeutic gastrointestinal endoscopy. We assessed the frequency of esophageal perforation after endoscopic procedures in a highly specialized endoscopy unit and compared clinical outcomes in patients undergoing either surgical or conservative management. Methods: From January 1985 to June 1996, 1011 instrumental endoscopic procedures (dilatation and bougienage) were performed in our department. The computerized complication database was searched to identify all patients with esophageal perforation during this same period, and their records were reviewed. Results: Seventeen esophageal perforations (1.7%) occurred in the course of 1011 procedures. Four perforations resulted from balloon dilatation, and 13 were secondary to bougienage. Six patients were managed surgically (35%), all of them recovering uneventfully. Eleven patients were managed conservatively, mainly because they were unfit for surgery. Survival rate in this group was 82% only two patients died, both of whom had underlying malignant disease. Conclusions: The current concept in management of esophageal perforations comprises surgical as well as medical treatment. In well-selected cases, non-operative treatment can be considered with favorable results.