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Supplemental material, sj-docx-1-tag-10.1177_17562848231177153 for Iron deficiency anemia impacts disease progression and healthcare resource consumption in patients with inflammatory bowel disease: a real-world evidence study by Gionata Fiorino, Jean-Frederic Colombel, Kostas Katsanos, Fermín Mearin, Jürgen Stein, Margherita Andretta, Stefania Antonacci, Loredana Arenare, Rita Citraro, Stefania Dell’Orco, Luca Degli Esposti, Antonio Ramirez de Arellano Serna, Neige Morin and Ioannis E. Koutroubakis in Therapeutic Advances in Gastroenterology

Chronic intestinal failure (CIF) is a rare but feared complication of Crohn’s disease. Depending on the remaining length of the small intestine, the affected intestinal segment, and the residual bowel function, CIF can result in a wide spectrum of symptoms, from single micronutrient malabsorption to complete intestinal failure. Management of CIF has improved significantly in recent years. Advances in home-based parenteral nutrition, in particular, have translated into increased survival and improved quality of life. Nevertheless, 60% of patients are permanently reliant on parenteral nutrition. Encouraging results with new drugs such as teduglutide have added a new dimension to CIF therapy. The outcomes of patients with CIF could be greatly improved by more effective prevention, understanding, and treatment. In complex cases, the care of patients with CIF requires a multidisciplinary approach involving not only physicians but also dietitians and nurses to provide optimal intestinal rehabilitation, nutritional support, and an improved quality of life. Here, we summarize current literature on CIF and short bowel syndrome, encompassing epidemiology, pathophysiology, and advances in surgical and medical management, and elucidate advances in the understanding and therapy of CIF-related complications such as catheter-related bloodstream infections and intestinal failure-associated liver disease.

BACKGROUND Transurethral resection of bladder tumor (TUR-BT) followed by chemoradiation (CRT) is a valid treatment option for patients with muscle-invasive bladder cancer (MIBC). This study aimed to investigate the efficacy of a tetramodal approach with additional regional hyperthermia (RHT). METHODS Patients with stages T2-4 MIBC were recruited at two institutions. Treatment consisted of TUR-BT followed by radiotherapy at doses of 57-58.2 Gy with concurrent weekly platinum-based chemotherapy and weekly deep RHT (41-43 °C, 60 min) within two hours of radiotherapy. The primary endpoint was a complete response six weeks after the end of treatment. Further endpoints were cystectomy-free rate, progression-free survival (PFS), local recurrence-free survival (LRFS), overall survival (OS) and toxicity. Quality of life (QoL) was assessed at follow-up using the EORTC-QLQ-C30 and QLQ-BM30 questionnaires. Due to slow accrual, an interim analysis was performed after the first stage of the two-stage design. RESULTS Altogether 27 patients were included in the first stage, of these 21 patients with a median age of 73 years were assessable. The complete response rate of evaluable patients six weeks after therapy was 93%. The 2-year cystectomy-free rate, PFS, LRFS and OS rates were 95%, 76%, 81% and 86%, respectively. Tetramodal treatment was well tolerated with acute and late G3-4 toxicities of 10% and 13%, respectively, and a tendency to improve symptom-related quality of life (QoL) one year after therapy. CONCLUSION Tetramodal therapy of T2-T4 MIBC is promising with excellent local response, moderate toxicity and good QoL. This study deserves continuation into the second stage.

Background: Osteopontin (OPN) is a glycosylated phosphoprotein found in human tissues and body fluids. OPN in breast milk is thought to play a major role in growth and immune system development in early infancy. Here, we investigated maternal factors that may affect concentrations of OPN in breast milk, and the possible associated consequences for the health of neonates. Methods: General characteristics, health status, dietary patterns, and anthropometric measurements of 85 mothers and their babies were recorded antenatally and during postnatal follow-up. Results: The mean concentration of OPN in breast milk was 137.1 ± 56.8 mg/L. Maternal factors including smoking, BMI, birth route, pregnancy weight gain, and energy intake during lactation were associated with OPN levels (p &lt, 0.05). Significant correlations were determined between body weight, length, and head circumference, respectively, and OPN levels after one (r = 0.442, p = &lt, 0.001, r = −0.284, p = &lt, r = −0.392, p = &lt, 0.001) and three months (r = 0.501, p = &lt, r = −0.450, p = &lt, r = −0.498, p = &lt, 0.001) of lactation. A negative relation between fever-related infant hospitalizations from 0–3 months and breast milk OPN levels (r = −0.599, p &lt, 0.001) was identified. Conclusions: OPN concentrations in breast milk differ depending on maternal factors, and these differences can affect the growth and immune system functions of infants. OPN supplementation in infant formula feed may have benefits and should be further investigated.

Iron deficiency, with or without anemia, is the most frequent hematological manifestation in individuals with cancer, and is especially common in patients with colorectal cancer. Iron is a vital micronutrient that plays an essential role in many biological functions, in the context of which it has been found to be intimately linked to cancer biology. To date, however, whereas a large number of studies have comprehensively investigated and reviewed the effects of excess iron on cancer initiation and progression, potential interrelations of iron deficiency with cancer have been largely neglected and are not well-defined. Emerging evidence indicates that reduced iron intake and low systemic iron levels are associated with the pathogenesis of colorectal cancer, suggesting that optimal iron intake must be carefully balanced to avoid both iron deficiency and iron excess. Since iron is vital in the maintenance of immunological functions, insufficient iron availability may enhance oncogenicity by impairing immunosurveillance for neoplastic changes and potentially altering the tumor immune microenvironment. Data from clinical studies support these concepts, showing that iron deficiency is associated with inferior outcomes and reduced response to therapy in patients with colorectal cancer. Here, we elucidate cancer-related effects of iron deficiency, examine preclinical and clinical evidence of its role in tumorigenesis, cancer progression and treatment response. and highlight the importance of adequate iron supplementation to limit these outcomes.

ZusammenfassungDie neue S3-Leitlinie Colitis stellt aktuelle und evidenzbasierte Empfehlungen zur Behandlung der Colitis ulcerosa zur Verfügung. Sie ersetzt damit die Vorläuferversion von 2011. Neben den neuesten Erkenntnissen zu Diagnostik und Therapie werden insbesondere infektiologische Probleme, chirurgische und Ernährungsmaßnahmen aufgegriffen. Unter der Federführung der DGVS wurde die Leitlinie gemeinsam mit 10 weiteren Fachgesellschaften und Patientenvertretern erarbeitet mit dem Ziel, eine optimale interdisziplinäre Versorgung der Patienten zu gewährleisten.

Background and Aims: The IL-12/23 inhibitor ustekinumab (UST) opened up new treatment options for patients with Crohn’s disease (CD). Due to the recent approval, real-world German data on long-term efficacy and safety are lacking. This study aimed to assess the clinical course of CD patients under UST therapy and to identify potential predictive markers. Methods: Patients with CD receiving UST treatment in three hospitals and two outpatient centers were included and retrospectively analyzed. Rates for short- and long-term remission and response were analyzed with the help of clinical (Harvey–Bradshaw Index (HBI)) and biochemical (C-reactive protein (CRP), Fecal calprotectin (fCal)) parameters for disease activity. Results: Data from 180 patients were evaluated. One-hundred-and-six patients had a follow-up of at least eight weeks and were included. 96.2% of the patients were pre-exposed to anti- TNFα agents and 34.4% to both anti-TNFα and anti-integrin antibodies. The median follow-up was 49.1 weeks (95% CI 42.03-56.25). At week 8, 51 patients (54.8%) showed response to UST, and 24 (24.7%) were in remission. At week 48, 48 (51.6%) responded to UST, and 25 patients (26.9%) were in remission. Steroid-free response and remission at week eight was achieved by 30.1% and 19.3% of patients, respectively. At week 48, 37.6% showed steroid-free response to UST, and 20.4% of the initial patient population was in steroid-free remission. Conclusion: Our study confirms short- and long-term UST effectiveness and tolerability in a cohort of multi-treatment-exposed patients.

Summary Background Ferric maltol was effective and well‐tolerated in iron deficiency anaemia patients with inflammatory bowel disease during a 12‐week placebo‐controlled trial. Aim To perform a Phase 3 extension study evaluating long‐term efficacy and safety with ferric maltol in inflammatory bowel disease patients in whom oral ferrous therapies had failed to correct iron deficiency anaemia. Methods After 12 weeks of randomised, double‐blind treatment, patients with iron deficiency anaemia and mild‐to‐moderate ulcerative colitis or Crohn's disease received open‐label ferric maltol 30 mg b.d. for 52 weeks. Results 111 patients completed randomised treatment and 97 entered the open‐label ferric maltol extension. In patients randomised to ferric maltol (‘continued’; n = 50), mean ± s.d. haemoglobin increased by 3.07 ± 1.46 g/dL between baseline and Week 64. In patients randomised to placebo (‘switch’; n = 47), haemoglobin increased by 2.19 ± 1.61 g/dL. Normal haemoglobin was achieved in high proportions of both continued and switch patients (89% and 83% at Week 64, respectively). Serum ferritin increased from 8.9 μg/L (baseline) to 26.0 μg/L (Week 12) in ferric maltol‐treated patients, and to 57.4 μg/L amongst all patients at Week 64. In total, 80% of patients reported ≥1 adverse event by Week 64. Adverse events considered related to ferric maltol were recorded in 27/111 (24%) patients: 8/18 discontinuations due to adverse events were treatment‐related. One patient was withdrawn due to increased ulcerative colitis activity. Conclusions Normal haemoglobin was observed in ≥80% of patients from weeks 20–64 of long‐term ferric maltol treatment, with concomitant increases in iron storage parameters. Ferric maltol was well‐tolerated throughout this 64‐week study.

Patients with inflammatory conditions such as inflammatory bowel disease (IBD), chronic heart failure (CHF), and chronic kidney disease (CKD) have high rates of iron deficiency with adverse clinical consequences. Under normal circumstances, serum ferritin levels are a sensitive marker for iron status but ferritin is an acute-phase reactant that becomes elevated in response to inflammation, complicating the diagnosis. Proinflammatory cytokines also trigger an increase in hepcidin, which restricts uptake of dietary iron and promotes sequestration of iron by ferritin within storage sites. Patients with inflammatory conditions may thus have restricted availability of iron for erythropoiesis and other cell functions due to increased hepcidin expression, despite normal or high levels of serum ferritin. The standard threshold for iron deficiency (

INTRODUCTION Adjuvant radiation therapy (aRT) after radical prostatectomy (RP) is associated with impaired urinary continence recovery as compared to surveillance. Less is known regarding the effect of salvage radiation therapy (sRT) dose intensification on continence outcomes. MATERIALS AND METHODS Urinary continence recovery was investigated within a multicentre randomized trial in biochemically recurrent prostate cancer patients who received either 64 Gy (32 fractions) or 70 Gy (35 fractions) sRT. Incontinence was assessed using Common Toxicity Criteria for Adverse Events v4.0 at baseline, at the end of sRT and 3 months afterward. Quality of life (QoL) was assessed with the EORTC QoL questionnaires C30 and PR25 at baseline and 3 months after completion of sRT. A total of 344 patients were evaluable. RESULTS At baseline 233 (68%) of patients were fully continent and 14% in both arms became incontinent three months after treatment. Of the remaining 111 (32%) patients being incontinent at baseline, continence recovery was achieved 3 months after sRT by 44% vs. 41% with 64 vs. 70 Gy, respectively (p = 0.8). This analysis is limited by its short follow-up. CONCLUSIONS Dose intensification of sRT had no impact on early urinary continence recovery or prevalence of de novo incontinence.

Although anemia is the most common systemic manifestation of inflammatory bowel disease (IBD), among the broad spectrum of extraintestinal disease complications encountered in IBD, including arthritis and osteopathy, it has generally received little consideration. However, not only in terms of frequency, but also with regard to its potential effect on hospitalization rates and on the quality of life and work, anemia is indeed a significant and costly complication of IBD. Anemia is multifactorial in nature, the most prevalent etiological forms being iron deficiency anemia (IDA) and anemia of chronic disease. In a condition associated with inflammation, such as IBD, the determination of iron status using common biochemical parameters alone is inadequate. A more accurate assessment may be attained using new iron indices including reticulocyte hemoglobin content, percentage of hypochromic red cells or zinc protoporphyrin. While oral iron supplementation has traditionally been a mainstay of IDA treatment, it has also been linked to extensive gastrointestinal side effects and possible disease exacerbation. However, many physicians are still reluctant to administer iron intravenously, despite the wide availability of a variety of new IV preparations with improved safety profiles, and despite the recommendations of international expert guidelines. This article discusses improved diagnostic and therapeutic strategies based on new clinical insights into the regulation of iron homeostasis.

Die Verknappung der fossilen Ressourcen erfordert die Suche nach alternativen Edukten für die Produktion von wichtigen Grundchemikalien. Diethylsuccinat auf Basis von biobasierter Bernsteinsäure kann als erneuerbare Alternative zu fossilen Rohstoffen für die Herstellung von g-Butyrolacton, 1,4-Butandiol und Tetrahydrofuran eingesetzt werden. Kommerziell erhältliche ZnO-freie Kupferkatalysatoren in einem Festbettreaktor zeigen eine vielversprechende Selektivität zu C4-Produkten, wobei 1,4-Butandiol an sauren Katalysatorbestandteilen wie Aluminium- und Zirconiumoxid zu Tetrahydrofuran dehydratisiert wird.

Background: In 2009, a survey on anaemia management in patients with inflammatory bowel disease (IBD) revealed that treatment practice is not in line with treatment recommendations. Despite a high prevalence of severe anaemia and absolute iron deficiency, most patients received oral instead of intravenous (i.v.) iron. Since additional data on effective correction of anaemia with i.v. iron emerged in the meantime (FERGIcor), a new survey was performed in 2011 to evaluate whether treatment practice changed. Methods: Gastroenterologists in France, Germany, Spain, UK and Switzerland completed questionnaires (Jun-Aug 2011) on patient demographics, blood tests at diagnosis and therapies for the last five IBD patients treated for anaemia within six months. Results are totals over all patients and ranges across countries. Results: 142 gastroenterologists (97 hospital-based only) reported 710 cases of IBD-associated anaemia. At the time of the survey, 83% (61-94%) were treated for anaemia (2009: 71% [59-79%]) and almost all of those (96% [2009: 91%]) received iron therapy, mainly as monotherapy (84% [2009: 78%]). Slightly more iron-treated patients but still only (32% [2009: 26%] received i.v. iron. Details of used treatment options and assessed haematological parameters are summarised and compared to the results of the 2009 survey in table 1. Conclusions: Treatment of IBD-associated anaemia in clinical practice did hardly change over the last two years despite new clinical data on the effectiveness of i.v. iron in correcting anaemia, and worse baseline Hb and iron status compared to a prior survey. The on-going lack in awareness of evidence-based recommendations on iron supplementation emphasises the need for new educational strategies to improve implementation of current and upcoming guidelines.

Aim: Iron deficiency (ID), a common complication of inflammatory bowel disease (IBD), can trigger hospitalization and increase morbidity. Intravenous (I.V.) iron is the recommended treatment for IBD-associated anemia. This study evaluated current European practice in diagnosis and treatment of IBD-associated anemia. Materials & Methods: Gastroenterologists from 4 European countries (Austria, Italy, The Netherlands and Sweden) completed questionnaires on the last five IBD patients treated for anemia within six months. The survey was performed between August and September 2010 and recorded details on patient demographics, blood tests, Hb-levels and iron parameters at diagnosis, and anemia therapies within twelve months prior to the survey. Results: 116 gastroenterologists (105 hospital-, 11 office-based) reported 575 cases of IBD-associated anemia. Anemia and iron status were mainly assessed by hemoglobin (Hb; 77%) and serum ferritin (58%). Transferrin saturation (TSAT) was tested in only 17% of patients. Median Hb at diagnosis was 9.4 g/dL (8.4-10.6 g/dL; Q1[25%]-Q3[75%]), ferritin 12.0 µg/L (7-30 µg/L) and TSAT 15.0% (8-34%). Severe anemia (Hb Conclusions: Although I.V. administration of iron is recommended as the preferred route for iron therapy, current practice continues to rely on oral iron preparations in most iron-treated patients with IBD, even when severely anemic. Insufficient replacement of iron or monitoring of iron status is indicated by the frequency of severe anemia in this cohort of 575 patients. The proportion of patients with IBD and untreated anemia or iron deficiency remains to be established, but greater awareness of guidelines for managing iron deficiency in IBD appears appropriate.

Protein catabolism should be reduced and protein synthesis promoted with parenteral nutrion (PN). Amino acid (AA) solutions should always be infused with PN. Standard AA solutions are generally used, whereas specially adapted AA solutions may be required in certain conditions such as severe disorders of AA utilisation or in inborn errors of AA metabolism. An AA intake of 0.8 g/kg/day is generally recommended for adult patients with a normal metabolism, which may be increased to 1.2–1.5 g/kg/day, or to 2.0 or 2.5 g/kg/day in exceptional cases. Sufficient non-nitrogen energy sources should be added in order to assure adequate utilisation of AA. A nitrogen calorie ratio of 1:130 to 1:170 (g N/kcal) or 1:21 to 1:27 (g AA/kcal) is recommended under normal metabolic conditions. In critically ill patients glutamine should be administered parenterally if indicated in the form of peptides, for example 0.3–0.4 g glutamine dipeptide/kg body weight/day (=0.2–0.26 g glutamine/kg body weight/day). No recommendation can be made for glutamine supplementation in PN for patients with acute pancreatitis or after bone marrow transplantation (BMT), and in newborns. The application of arginine is currently not warranted as a supplement in PN in adults. N-acetyl AA are only of limited use as alternative AA sources. There is currently no indication for use of AA solutions with an increased content of glycine, branched-chain AAs (BCAA) and ornithine-α-ketoglutarate (OKG) in all patients receiving PN. AA solutions with an increased proportion of BCAA are recommended in the treatment of hepatic encephalopathy (III–IV). Ein Proteinkatabolismus soll bei parenteraler Ernährung (PE) vermindert und anabole Stoffwechselprozesse gefördert werden. Standard-Aminosäure (AS)-Lösungen werden empfohlen, falls nicht in Sondersituationen z. B. bei schweren AS-Verwertungsstörungen oder bei angeborenen Stoffwechselstörungen spezifisch adaptierte AS-Lösungen eingesetzt werden müssen. Für erwachsene Patienten in ausgeglichenem Stoffwechselzustand wird eine AS-Zufuhr von 0,8 g/kg/Tag empfohlen, die auf 1,2–1,5 g/kg/Tag oder in Ausnahmefällen auch auf 2,0–2,5 g/kg/Tag gesteigert werden kann. Zur Gewährleistung einer angemessenen Utilisation von AS sollten ausreichend Nicht-Stickstoff-Energieträger zugegeben werden. Das angestrebte Verhältnis zwischen Stickstoff- und Energiezufuhr (Stickstoff-Kalorien-Verhältnis) sollte unter Normalbedingungen 1:100–1:130 (g N:kcal) bzw. 1:16–1:21 (g AS:kcal) betragen. Glutamin sollte parenteral bei kritisch Kranken, sofern indiziert, in Form von Peptiden verabreicht werden, wie z.B. 0,3–0,4 g Glutamin-Dipepetid/kg KG/Tag (entsprechend 0,2–0,26 g Glutamin/kg KG/Tag). Für Patienten mit akuter Pankreatitis, nach Knochenmarkstransplantation sowie für Neugeborene kann derzeit keine Empfehlung für eine Glutaminsupplementierung mit der PE ausgesprochen werden. Der Einsatz von Arginin als Supplement in der PE beim Erwachsenen ist derzeit nicht gerechtfertigt. Den N-azetylierten AS kommen als alternative Aminosäurenquellen zur Zeit nur eine begrenzte Bedeutung zu. Für eine generelle Verwendung von AS-Lösungen mit einem erhöhten Gehalt von Glyzin und verzweigtkettigten AS (VKAS) wie auch für Ornithin-α-Ketoglutarat (OKG) besteht keine gesicherte Indikation. Die Wirksamkeit von AS-Lösungen mit erhöhtem Anteil an VKAS in der Behandlung der hepatischen Enzephalopathie (III–IV) wird empfohlen.

Wirkungen von Heilpflanzen, Gewürzen, Tees und Lebensmitteln werden in der Naturheilkunde seit der Antike genutzt. Pharmakologisch wirksam sind in der Regel nur die sekundären Pflanzeninhaltsstoffe. Diese in den oft aus vielen Bestandteilen zusammengesetzten Naturstoffen aufzuspüren und ihren molekularbiologischen Wirkungsmechanismus im Körper aufzuklären, ist das Ziel eines Forschungsnetzwerks am Frankfurter ZAFES (Zentrum für Arzneimittelforschung, -Entwicklung und -Sicherheit). So konnten Pharmazeuten und Kliniker gemeinsam herausfinden, wie ein Bestandteil des Rotweins, das Resveratrol, vor Darmkrebs schützt. Die Inhaltsstoffe von Salbei und Rosmarin bieten vielversprechende Ausgangspunkte für neue Medikamente gegen Altersdiabetes. Weihrauch, Myrte und Johanniskraut enthalten Wirkstoffe, die Schlüsselenzyme für Entzündungsreaktionen – etwa bei rheumatischen Beschwerden – hemmen.

Am Max-Planck-Institut für Quantenoptik steht das 10 Hz Lasersystem ATLAS zur Verfügung, dessen Pulse bei einer Dauer von 160 fs Energien bis zu 800 mJ erreichen und auf Intensitäten bis zu 1019 W/cm2 fokussiert werden können. Bei Bestrahlung dünner Festkörper-Folien (Targets) mit solchen Intensitäten werden zuerst Elektronen auf relativistische Geschwindigkeiten   1 beschleunigt. Diese Elektronen durchdringen das Target und verlassen es rückseitig in Richtung des Laserstrahles bei ponderomotiver Beschleunigung oder entlang der Targetnormalen bei Beschleunigung durch Resonanz-Absorption. Mit konventionellen Magnetfeld-Spektrometern kann nur die Energieverteilung derartiger Elektronenströme bis in den MeV-Bereich bestimmt werden. Da die Elektronen nach dem Target im Vakuum eine Wegstrecke von einigen cm zurücklegen müssen, unterliegen diese Ströme allerdings der Alfven-Grenze IA = 17,5  kA. Ab dieser Stromstärke werden die Elektronen von ihrem eigenen Magnetfeld auf Kreisbahnen gezwungen, so daß der Teilchenfluß zusammenbricht bis der Alfven-Wert unterschritten ist. Bei Laser-Plasma-Experimenten können nun Stromstärken deutlich größer als 1 MegaAmpere auftreten, so daß man gezwungen ist, die Elektronen-Diagnostik unmittelbar mit dem Beschleunigungsbereich des Laser-Targets zu verbinden, wie dies bei der Messung von Röntgenstrahlung oder der Übergangsstrahlung möglich ist. Da der Energiebereich der Röntgendiagnostik um die 10 keV und optische Abbildungen wegen der kleinen Wellenlänge auf wenige Möglichkeiten eingeschränkt sind, können nur begrenzt Aussagen über die Auswirkungen von relativistischen Elektronen bei der Wechselwirkung mit Plasmen gemacht werden. Die Übergangsstrahlung ist sensitiv für den gesamten Energiebereich und deswegen eine Unterscheidung der Elektronen in Energie und dazugehöriger räumlicher Verteilung schwierig. Mit dem Cerenkov-Effekt steht in dieser Arbeit eine Diagnostik zur Verfügung, die auf Elektronenströme aus der Laser-Plasma-Wechselwirkung bei relativistischen Intenstitäten >1018 W/cm2 anwendbar ist. Der Brechungsindex eines optisch transparenten Cerenkov-Mediums legt zusammen mit der optischen Abbildung des Cerenkov-Lichts (im sichtbaren Spektralbereich) den Energiebereich zwischen 180 keV und 230 keV - bei Trajektorien parallel zur Targetnormalen - fest. Mit sehr dünnen Cerenkov-Medien (z.B. 50 µm Tesafilm, direkt auf die Targetrückseite aufgeklebt) und einer schnell geschalteten CCD kann eine örtliche Auflösung bis zu 4 µm genutzt werden, um die Stromprofile und die Anzahl der Elektronen zu messen. Bei Aluminium- und Polypropylen-Targets mit einer Dicke bis zu 10 µm werden filamentierte Elektronenströme großer Dichte gemessen, die von dem Laserpuls in einem ausgedehnten Vorplasma beschleunigt werden. Mit zunehmender Targetdicke verschwindet die Filamentierung und geht in zwei breite Gauß-förmige Lichtverteilungen über. Entsprechend den experimentellen Verhältnissen werden diese beiden Elektronenströme den Beschleunigungsmechanismen der Resonanz-Absorption und der ponderomotiven Kraft zugeordnet. Auch im Fall der Filamentierung wird nachgewiesen, daß die Elektronen ponderomotiv beschleunigt werden. Dazu läßt sich die Anzahl der gemessenen Elektronen (proportional zur Anzahl der Cerenkov Photonen und zur Dicke des Cerenkov Mediums) als Funktion der Laser-Intensität auswerten. Darüber hinaus zeigen Experimente unter Einsatz einer weiteren Pockelszelle nach dem Regenerativen Verstärker, mit dem sich der ASE-Vorpuls (amplified spontaneous emission) mit einer Dauer zwischen 0,5 und 5 ns kontrollieren läßt, daß das Vorplasma einen wesentlichen Einfluß auf die Elektronenbeschleunigung hat. Die ASE-Intensität und -Energie ist groß genug (1012 W/cm2), um ein Vorplasma mit unterkritischer Dichte ( ) zu zünden, in dem die Länge des Dichtegradienten von der Größenordnung (100 µm) der Ringdurchmesser der filamentierten Strukturen ist. Der Durchmesser eines einzelnen Stromfilaments von mehr als 10 µm wird vor allem durch die Hintergrundplasmadichte eingestellt, in dem durch die Ladungstrennung starke Rückströme aufgebaut werden. In dieser Situation der sich begegnenden Ströme können die Magnetfelder zumindest teilweise kompensiert werden, so daß die Vorwärtsströme die Alfven-Grenze für die Stromstärke um viele Größenordnungen übersteigen können. Bei diesen Verhältnissen bilden sich über die Weibel-Instabiltiät die filamentierten Ringstrukturen, die bereits in entsprechenden 2D- und 3D-PIC-Simulationen (Particle-In-Cell) untersucht wurden. In diesem Zusammenhang wurde auch das sog. Anomale Stoppen vorhergesagt, das zu einem Energieübertrag der Elektronen an das Hintergrundplasma führt, der deutlich größer ist als bei klassischen Coulomb-Stößen. Das Anomale Stoppen geht zurück auf die Koaleszenz ("merging") benachbarter Filamente, die jeweils ein Vielfaches der Alfven-Stromstärke transportieren können. Die dabei aufgebauten starken elektrischen und magnetischen Felder (1010 V/cm, Mega-Gauss) beziehen ihren Energieinhalt aus der kinetischen Energie der Elektronen und Übertragen diesen in einer lokalen, räumlichen Expansion an die Plasma-Ionen. Durch Messung der Elektronenzahl in Abhängigkeit von der Target-Dicke kann die deutliche Abnahme der Stromstärke nach wenigen µm Festkörperdicke nachgewiesen werden. Anhand eines einfachen Modells wird der Energieübertrag numerisch simuliert und mit klassischen Verlustmechanismen verglichen.

E. coli ist ein wesentlicher Bestandteil der physiologischen Darmflora des Menschen. Die üblicherweise im Darm vorkommenden Kolibakterien sind apathogen und für den Menschen eher nützlich (Sonnenborn u. Greinwald 1990). Allerdings kennen wir bei dieser Bakterienspezies auch ein breites Spektrum von pathogenen Wirkungstypen: uropathogene E. coli, sepsisassoziierte E. coli und verschiedene darmpathogene E. coli.