25 research outputs found

    Quality assessment of CIPP lining in sewers:Crucial knowledge acquired by IKT and research gaps identified in Germany

    Get PDF
    Deterioration of buried water and sewer pipes is a significant concern among utilities around the world. Cured-In-Place-Pipe (CIPP) is one of the techniques commonly adopted to rehabilitate pipes. The main purpose of this paper is to provide a brief, but comprehensive, summary of information needed by researchers, engineers and municipalities to recognize the barriers and difficulties that may arise during CIPP sewer rehabilitation work. Thus, this paper outlines the issues and challenges associated with CIPP rehabilitation of main and lateral sewers by analyzing a series of projects conducted by IKT-Institute for Underground Infrastructure in Germany over the last two decades. Finally, ideas for further research are then proposed to reduce the obstacles and risks linked with this technique

    Fermentation of glycerol to 1,3-propanediol by Klebsiella and Citrobacter strains

    No full text
    Glycerol-fermenting anaerobes were enriched with glycerol at low and high concentrations in order to obtain strains that produce 1,3-propanediol. Six isolates were selected for more detailed characterization; four of them were identified as Citrobacter freundii, one as Klebsiella oxytoca and one as K. pneumoniae. The Citrobacter strains formed 1,3-propanediol and acetate and almost no by-products, while the Klebsiella strains produced varying amounts of ethanol in addition and accordingly less 1,3-propanediol. Enterobacterial strains of the genera Enterobacter, Klebsiella, and Citrobacter from culture collections showed similar product patterns except for one group which formed limited amounts of ethanol, but no propanediol. Seven strains were grown in pH-controlled batch cultures to determine the parameters necessary to evaluate their capacity for 1,3-propanediol production. K. pneumoniae DSM 2026 exhibited the highest final concentration (61 g/l) and the best productivity (1.7 g/1 h) whereas C. freundii Zu and K2 achieved only 35 g/1 and 1.4 g/1 h, respectively. The Citrobacter strains on the other hand gave somewhat better yields which were very close to the theoretical optimum of 65 mol %

    Polysaccharide Synthesis of the Levansucrase SacB from Bacillus megaterium Is Controlled by Distinct Surface Motifs*

    Get PDF
    Despite the widespread biological function of carbohydrates, the polysaccharide synthesis mechanisms of glycosyltransferases remain largely unexplored. Bacterial levansucrases (glycoside hydrolase family 68) synthesize high molecular weight, β-(2,6)-linked levan from sucrose by transfer of fructosyl units. The kinetic and biochemical characterization of Bacillus megaterium levansucrase SacB variants Y247A, Y247W, N252A, D257A, and K373A reveal novel surface motifs remote from the sucrose binding site with distinct influence on the polysaccharide product spectrum. The wild type activity (kcat) and substrate affinity (Km) are maintained. The structures of the SacB variants reveal clearly distinguishable subsites for polysaccharide synthesis as well as an intact active site architecture. These results lead to a new understanding of polysaccharide synthesis mechanisms. The identified surface motifs are discussed in the context of related glycosyltransferases

    Evaluation of EGFR inhibitor‐mediated acneiform skin toxicity within the double‐blind randomized EVITA trial: A thorough gender‐specific analysis using the WoMo score

    No full text
    Acne‐like skin reactions frequently occur in patients undergoing treatment with drugs inhibiting the epidermal growth factor receptor. Recently, the effects of vitamin K1 containing cream (Reconval K1) as prophylactic skin treatment in addition to doxycycline were explored in a double‐blind randomized phase II trial (EVITA) in patients with metastatic colorectal cancer receiving cetuximab. EVITA demonstrated a trend towards less severe skin rash in Reconval K1‐treated patients using the tripartite WoMo skin reaction grading score as a thorough tool for quantification of drug related skin reactions. This gender‐specific analysis of the EVITA trial evaluated the application of the WoMo score for assessment of epidermal growth factor receptor (EGFR)‐related skin toxicities according to treatment arm and gender. To show the robustness of results parametric and non‐parametric statistical analyses were conducted. All three parts of the WoMo score independently demonstrated the superiority of the treatment arm (Reconval K1) regarding a significant reduction in acneiform skin reactions in women. Men did not benefit from Reconval K1 cream at any time point in none of the WoMo score analyses. The treatment effect in women was confirmed by the use of skin rash categories based on the final WoMo overall score and mixed effect longitudinal multiple linear regression analysis. The WoMo score represents a sensitive tool for studies exploiting treatments against EGFR mediated acne‐like skin rash. Part C of the WoMo score seems to be sufficient for quantification of drug related skin toxicities in further studies. Standard WoMo skin reaction score values for future studies are provided

    Vitamin K1 cream significantly reduces incidence and severity of cetuximab-related acneiform skin rash in women: a post hoc analysis of the EVITA trial

    No full text
    Patients treated with drugs targeting the epidermal growth factor receptor (EGFR) frequently develop acneiform skin toxicities. These skin reactions can impair treatment adherence and clinical outcome. Prophylactic treatment with doxycycline reduces the severity of skin toxicities. ..

    Perioperative FLOT plus ramucirumab for resectable esophagogastric adenocarcinoma - A randomized phase II/III trial of the German AIO and Italian GOIM

    No full text
    : This multicenter, randomized phase II/III study evaluated the addition of the vascular endothelial growth factor receptor-2 inhibitor ramucirumab to FLOT as perioperative treatment for resectable esophagogastric adenocarcinoma. Patients received either FLOT alone (Arm A) or combined with ramucirumab followed by ramucirumab monotherapy (Arm B). The primary endpoint for the phase II portion was the pathological complete or subtotal response (pCR/pSR) rate. Baseline characteristics were comparable between both arms with a high rate of tumors signet-ring cell component (A:47% B:43%). No between-arm difference in pCR/pSR rate was seen (A:29% B:26%), therefore the transition to phase III was not pursued. Nevertheless, the combination was associated with a significantly increased R0-resection rate compared to FLOT alone (A:82% B:96%; p=0.009). In addition, the median disease-free survival was numerically improved in Arm B (A:21 months B:32 months, HR 0.75, p=0.218), while the median overall survival was similar in both treatment arms (A:45 months B:46 months, HR 0.94, p=0.803). Patients with Siewert type I tumors receiving transthoracic esophagectomy with intrathoracic anastomosis showed an increased risk of serious postoperative complications after ramucirumab treatment, therefore recruitment of those patients was stopped after the first-third of the study. Overall, surgical morbidity and mortality was comparable, whereas more non-surgical grade≥3 adverse events were observed with the combination, especially anorexia (A:1% B:11%), hypertension (A:4% B:13%) and infections (A:19% B:33%). The combination of ramucirumab and FLOT as perioperative treatment shows efficacy signals, particularly in terms of R0 resection rates, for a study population with a high proportion of prognostically poor histological subtypes, and further evaluation in this subgroup seems warranted. This article is protected by copyright. All rights reserved
    corecore