A simple liquid state 1H NMR measurement to directly determine the surface hydroxyl density of porous silica.

Silica is widely used in industrial applications and its performance is partially decided by its surface hydroxyl density αOH. Here we report a quick, simple liquid 1H NMR method to determine αOH using a benchtop 1H NMR spectrometer. The results show excellent agreement with the literature with an αOH range from 4.16 to 6.56 OH per nm2.

A bioimpedance analysis of head-and-neck cancer patients undergoing radiotherapy.

Malnutrition is a frequent manifestation in patients with head-and-neck cancer undergoing radiation therapy and a major contributor to morbidity and mortality. Thus, body composition is an important component of an overall evaluation of nutrition in cancer patients. Malnutrition is characterized by weight loss, loss of muscle mass, changes in cell membrane integrity, and alterations in fluid balance. Bioelectrical impedance analysis is a method to analyze body composition and includes parameters such as intracellular water content, extracellular water content, and cell membrane integrity in the form of a phase angle (Φ). Bioelectrical impedance analysis has consistently been shown to have prognostic value with respect to mortality and morbidity in patients undergoing chemotherapy. The goal of the present study was to evaluate the relationship between Φ, time, intracellular water content, and weight for head-and-neck cancer patients undergoing radiotherapy. The results demonstrate that Φ decreases with time and increases with intracellular water content and weight.

Perforated Diverticulitis with Generalized Peritonitis: Low Stoma Rate Using a "Damage Control Strategy".

PURPOSE: Optimal surgical management of perforated diverticulitis of the sigmoid colon has yet to be clearly defined. The purpose of this study was to evaluate efficacy of a "Damage Control Strategy" (DCS). MATERIALS AND METHODS: Patients with perforated diverticulitis of the sigmoid colon complicated by generalized peritonitis (Hinchey III and IV) surgically treated according to a damage control strategy between May 2011 and February 2017 were enrolled in the present multicenter retrospective cohort study. Data were collected at three surgical centers. DCS comprises a two-stage concept: [1] limited resection of the perforated colon segment with oral and aboral blind closure during the emergency procedure and [2] definitive reconstruction at scheduled second laparotomy (anastomosis ∓ loop ileostomy or a Hartmann's procedure) after 24-48 h. RESULTS: Fifty-eight patients were included into the analysis [W:M 28:30, median age 70.1 years (30-92)]. Eleven patients (19%) initially presented with fecal peritonitis (Hinchey IV) and 47 patients with purulent peritonitis (Hinchey III). An anastomosis could be created during the second procedure in 48 patients (83%), 14 of those received an additional loop ileostomy. In the remaining ten patients (n = 17%), an end colostomy was created at second laparotomy. A fecal diversion was performed in five patients to treat anastomotic complications. Thus, altogether, 29 patients (50%) had stoma at the end of the hospital stay. The postoperative mortality was 9% (n = 5), and median postoperative hospital stay was 18.5 days (3-66). At the end of the follow-up, 44 of 53 surviving patients were stoma free (83%). CONCLUSION: The use of the Damage Control strategy leads to a comparatively low stoma rate in patients suffering from perforated diverticulitis with generalized peritonitis.

Damage control surgery in perforated diverticulitis: ongoing peritonitis at second surgery predicts a worse outcome.

PURPOSE: Damage control strategy (DCS) is a two-staged procedure for the treatment of perforated diverticular disease complicated by generalized peritonitis. The aim of this retrospective multicenter cohort study was to evaluate the prognostic impact of an ongoing peritonitis at the time of second surgery. METHODS: Consecutive patients who underwent DCS for perforated diverticular disease of the sigmoid colon with generalized peritonitis at four surgical centers were included. Damage control strategy is a two-stage emergency procedure: limited resection of the diseased colonic segment, closure of oral and aboral colon, and application of a negative pressure assisted abdominal closure system at the initial surgery followed by second laparotomy 48 h later. Therein, decision for definite reconstruction (anastomosis or Hartmann's procedure (HP)) is made. An ongoing peritonitis at second surgery was defined as presence of visible fibrinous, purulent, or fecal peritoneal fluid. Microbiologic findings from peritoneal smear at first surgery were collected and analyzed. RESULTS: Between 5/2011 and 7/2017, 74 patients underwent a DCS for perforated diverticular disease complicated by generalized peritonitis (female: 40, male: 34). At second surgery, 55% presented with ongoing peritonitis (OP). Patients with OP had higher rate of organ failure (32 vs. 9%, p = 0.024), higher Mannheim Peritonitis Index (25.2 vs. 18.9; p = 0.001), and increased operation time (105 vs. 84 min., p = 0.008) at first surgery. An anastomosis was constructed in all patients with no OP (nOP) at second surgery as opposed to 71% in the OP group (p < 0.001). Complication rate (44 vs. 24%, p = 0.092), mortality (12 vs. 0%, p = 0.061), overall number of surgeries (3.4 vs. 2.4, p = 0.017), enterostomy rate (76 vs. 36%, p = 0.001), and length of hospital stay (25 vs. 18.8 days, p = 0.03) were all increased in OP group. OP at second surgery occurred significantly more often in patients with Enterococcus infection (81 vs. 44%, p = 0.005) and with fungal infection (100 vs. 49%, p = 0.007). In a multivariate analysis, Enterococcus infection was associated with increased morbidity (67 vs. 21%, p < 0.001), enterostomy rate (81 vs. 48%, p = 0.017), and anastomotic leakage (29 vs. 6%, p = 0.042), whereas fungal peritonitis was associated with an increased mortality (43 vs. 4%, p = 0.014). CONCLUSION: Ongoing peritonitis after DCS is a predictor of a worse outcome in patients with perforated diverticulitis. Enterococcal and fungal infections have a negative impact on occurrence of OP and overall outcome.

Prospective multicentre clinical study on inter- and intrapatient genetic variability for antimicrobial resistance of Helicobacter pylori.

OBJECTIVES: We report on a large prospective, multicentre clinical investigation on inter- and intrapatient genetic variability for antimicrobial resistance of Helicobacter pylori. METHODS: Therapy-naive patients (n = 2004) who had undergone routine diagnostic gastroscopy were prospectively included from all geographic regions of Austria. Gastric biopsy samples were collected separately from antrum and corpus. Samples were analysed by histopathology and real-time PCR for genotypic resistance to clarithromycin and quinolones. Clinical and demographic information was analysed in relation to resistance patterns. RESULTS: H. pylori infection was detected in 514 (26%) of 2004 patients by histopathology and confirmed in 465 (90%) of 514 patients by real-time PCR. PCR results were discordant for antrum and corpus in 27 (5%) of 514 patients, indicating inhomogeneous infections. Clarithromycin resistance rates were 17% (77/448) and 19% (84/455), and quinolone resistance rates were 12% (37/310) and 10% (32/334) in antrum and corpus samples, respectively. Combination of test results per patient yielded resistance rates of 21% (98/465) and 13% (50/383) for clarithromycin and quinolones, respectively. Overall, infection with both sensitive and resistant H. pylori was detected in 65 (14%) of 465 patients. CONCLUSIONS: Anatomically inhomogeneous infection with different, multiple H. pylori strains is common. Prospective clinical study design, collection of samples from multiple sites and microbiologic methods that allow the detection of coinfections are mandatory for collection of reliable data on antimicrobial resistance patterns in representative patient populations. (ClinicalTrials.gov identifier: NCT02925091).

Damage control strategy for the treatment of perforated diverticulitis with generalized peritonitis.

BACKGROUND: The best surgical strategy for the management of perforated diverticulitis with generalized peritonitis of the sigmoid colon is not clearly defined. The aim of this retrospective cohort study was to evaluate the value of a damage control strategy. METHODS: All patients who underwent emergency laparotomy for perforated diverticular disease of the sigmoid colon with generalized peritonitis between 2010 and 2015 were included. The damage control strategy (study group), included a two- stage procedure: limited resection of the diseased colonic segment, closure of proximal colon and distal stump, and application of an abdominal vacuum at the initial surgery followed by second-look laparotomy 24-48 h later At this point a choice was made between anastomosis and Hartmann's procedure. The control group consisted of patients receiving definitive reconstruction (anastomosis or Hartmann's procedure) at the initial operation. RESULTS: Thirty-seven patients were included in the study. Damage control strategy was applied in 19 patients and the control group consisted of 18 patients. Both groups were comparable in terms of demographics, severity of peritonitis, and comorbidities. The overall postoperative mortality was 11 % (n = 4). There were no statistically significant differences between both groups regarding postoperative morbidity and mortality; however, a significantly higher proportion of patients in the control group had a stoma after the initial hospital stay (83 vs. 47 %, p = 0.038). This difference was still significant after adjustment for sex, age, Mannheim Peritonitis Index, American Society of Anesthesiologists class and presence of septic shock at presentation. At the end of the follow-up period, 15 of 17 survivors in the study group and 13 of 16 survivors in the control group had their intestinal continuity restored (p = 0.66). CONCLUSIONS: Damage control strategy in patients with generalized peritonitis due to perforated diverticulitis leads to a significantly reduced stoma rate after the initial hospital stay without an increased risk of postoperative morbidity.

DNA from microdissected tissues may be extracted and stored on microscopic slides.

With regard to complex structure of tissues, laser capture microdissection represents an important step in analytical workflow streaming to proper molecular characterization of different cell types in examined samples. Therefore the simple method for simultaneous processing of higher numbers of microdissected tissues leading not only to rapid and efficient DNA isolation but allowing also the repeated sampling and easy storage may be useful in the practice of histopathological laboratories. We elaborated such a methodology applicable downstream after the microdissection from formalin-fixed paraffin embedded tissues.The tissues for examination are microdissected directly into the circular areas having the diameter 2 mm and marked on the microscopic slide. In this way, one slide is able to accommodate multiple samples. The DNA extraction is performed in low volume of buffer with Proteinase K in a droplet covered by mineral oil just on the slide. Mineral oil in the quality for molecular biology not only avoids evaporation during DNA extraction, but it helps to position the microdisssected tissue, to control the level of cell lysis microscopically and to protect the DNA sample during subsequent manipulations. We provided the evidence that DNA isolated by our methodology remains in the positions on microscopic slide for months without any changes in the lengths of available fragments and that it may be removed from each position repetitively for different kinds of analysis. The new methodological approach presented by us can be practically applied in broad spectrum of laboratories performing routinely genetic analysis on microdissected tissues.

Genome-wide methylation analysis of tubulocystic and papillary renal cell carcinomas.

Tubulocystic renal cell carcinoma (TRCC) represents a rare tumor with incidence lower than 1 % of all renal carcinomas. This study was undertaken to contribute to characterization of molecular signatures associated with TRCC and to compare them with the features of papillary renal cell carcinoma (PRCC) at the level of genome wide methylation analysis.We performed methylated DNA immunoprecipitation (MeDIP) coupled with microarray analysis (Roche NimbleGen). Using the CHARM package, we compared the levels of gene methylation between paired samples of tumors and control renal tissues of each examined individual. We found significant global demethylation in all tumor samples in comparison with adjacent kidney tissues of normal histological appearance but no significant differences in gene methylation between the both compared tumor entities. Therefore we focused on characterization of differentially methylated regions between both tumors and control tissues. We found 42 differentially methylated genes.Hypermethylated genes for protocadherins (PCDHG) and genes coding for products associated with functions of plasma membrane were evaluated as significantly overrepresented among hypermethylated genes detected in both types of renal cell carcinomas.In our pilot study, we provide the first evidence that identical features in the process of carcinogenesis leading to TRCC and/or to PRCC may be found at the gene methylation level.

[Improvement of emergency physician education through simulator training. Consideration on the basis of the model project "NASimSaar25"]. / Verbesserung der Notarztausbildung durch Simulatortraining. Betrachtung anhand des Modellprojekts "NASimSaar25"

BACKGROUND: Prehospital emergency medicine is a challenge for trainee emergency physicians. Rare injuries and diseases as well as patients in extreme age groups can unexpectedly face emergency physicians. In the regulations on medical education the German Medical Association requires participation in 50 emergency missions under the supervision of an experienced emergency physician. This needs to be improved because on-the-job training does not generally represent the whole spectrum of emergency medicine and a good and structured training under on call conditions is nearly impossible. AIM: The subject of the model project described was whether practical training for emergency physicians can be achieved by participation in simulation training instead of real emergency situations. MATERIAL AND METHODS: After modification of the Saarland regulations on medical education it was possible to replace up to 25 participations in emergency missions by simulation training. The concept of the course NASimSaar25 requires participants to complete 25 simulator cases in 3 days in small training groups. Emergency situations from all medical disciplines need to be treated. A special focus is on the treatment of life-threatening and rare diseases and injuries. Modern simulators and actors are used. The debriefings are conducted by experienced tutors based on approved principles. Medical contents, learning targets from the field of crew resource management (CRM) and soft skills are discussed in these debriefings. RESULTS: Education in the field of emergency medicine can be improved by simulator-based learning and training. However, practical work under a tutor in real and clinical experience cannot be completely replaced by simulation. Simulator training can only be successful if theoretical knowledge has already been acquired. CONCLUSION: A simulator-based course concept can result in an improvement of emergency medical education. The model project NASimSaar25 was well received by the target audience and mostly very well evaluated in terms of learning and reality. If this project becomes established the demand on simulation-based training will increase. The training should achieve a consistent standard of quality.

[Colorectal cancer: screening and surveillance in inflammatory bowel diseases - consensus of the working group for inflammatory bowel diseases of the Austrian Society of Gastroenterology and Hepatology]. / Kolorektales Karzinom: Screening und Surveillance bei chronisch entzündlichen Darmerkrankungen - Konsensus der Arbeitsgruppe für chronisch entzündliche Darmerkrankungen der ÖGGH.

Patients with ulcerative colitis and Crohn's colitis are at increased risk of colorectal cancer (CRC). This risk is dependent on the duration and extent of disease, inflammatory activity and possible additional risk factors. Thus, the aim is to reduce this risk and to detect dysplastic and malignant lesions at an early stage. The working group for Inflammatory Bowel Diseases (IBD) of the Austrian Society of Gastroenterology and Hepatology (ÖGGH) has developed consensus statements on the following topics: risk of colorectal cancer, screening and surveillance, procedure of surveillance colonoscopy, dysplasia and its management, and chemoprevention. This consensus is intended to increase awareness of the increased risk of CRC in IBD and to support a standardised approach in cancer prevention.

Poster - Thur Eve - 57: Craniospinal irradiation with jagged-junction IMRT approach without beam edge matching for field junctions.

PURPOSE: Craniospinal irradiation were traditionally treated the central nervous system using two or three adjacent field sets. A intensity-modulated radiotherapy (IMRT) plan (Jagged-Junction IMRT) which overcomes problems associated with field junctions and beam edge matching, improves planning and treatment setup efficiencies with homogenous target dose distribution was developed. METHODS AND MATERIALS: Jagged-Junction IMRT was retrospectively planned on three patients with prescription of 36 Gy in 20 fractions and compared to conventional treatment plans. Planning target volume (PTV) included the whole brain and spinal canal to the S3 vertebral level. The plan employed three field sets, each with a unique isocentre. One field set with seven fields treated the cranium. Two field sets treated the spine, each set using three fields. Fields from adjacent sets were overlapped and the optimization process smoothly integrated the dose inside the overlapped junction. RESULTS: For the Jagged-Junction IMRT plans vs conventional technique, average homogeneity index equaled 0.08±0.01 vs 0.12±0.02, and conformity number equaled 0.79±0.01 vs 0.47±0.12. The 95% isodose surface covered (99.5±0.3)% of the PTV vs (98.1±2.0)%. Both Jagged-Junction IMRT plans and the conventional plans had good sparing of the organs at risk. CONCLUSIONS: Jagged-Junction IMRT planning provided good dose homogeneity and conformity to the target while maintaining a low dose to the organs at risk. Jagged-Junction IMRT optimization smoothly distributed dose in the junction between field sets. Since there was no beam matching, this treatment technique is less likely to produce hot or cold spots at the junction in contrast to conventional techniques.

Remission of paroxysmal atrial fibrillation with iron reduction in haemophilia A.

SUMMARY: Two male first cousins with mild haemophilia A had baseline factor VIII levels of 12-15% and experienced bleeding requiring coagulation factor infusion therapy with trauma and surgical procedures. Both the patients with haemophilia A also had electrocardiographically documented symptomatic paroxysmal atrial fibrillation (PAF) for several years that had become resistant to pharmacological suppression. Radiofrequency ablation was considered in both the cases but deferred considering refusal of consent by the patients to undergo the procedure. Remission of arrhythmias has been reported in patients with iron-overload syndromes. Body iron stores assessed by serum ferritin levels were elevated in both men but neither had the C282Y or H63D genes for haemochromatosis. Calibrated reduction of iron stores by serial phlebotomy, avoiding iron deficiency, was followed by remission of symptomatic PAF in both cases. Iron reduction may be an effective treatment for arrhythmias apart from the classic iron-overload syndromes and deserves further study particularly in patients with bleeding disorders who might be at risk for arrhythmias and other diseases of ageing.

Austrian experiences with redo antireflux surgery.

BACKGROUND: From 1996, the entire number of fundoplications performed in Austria increased dramatically, favoring the laparoscopic technique. Despite good results, some patients experience failure of antireflux surgery and therefore require redo surgery if medical therapy fails to control symptoms. The aim of the study was to describe the refundoplication policy in Austria with evaluation of the postoperative results. METHODS: A questionnaire was sent to all Austrian surgical departments at the beginning of 2003 with questions about redo fundoplications (number, techniques, intraoperative complications, history, migration of patients, preoperative workup, mortality, and postoperative long-term complaints). It also included questions about primary fundoplications (number, technique, postoperative symptoms). RESULTS: Out of 4,504 primary fundoplications performed in Austria since 1990, 3,952 have been carried out laparoscopically. In a median of 31 months after the primary operation, 225 refundoplications have been performed, laparoscopically in the majority of patients. The Nissen and the partial posterior fundoplication were the preferred techniques. The conversion rate in these was 10.8%, mainly because of adhesions and lacerations of the spleen, the stomach, and the esophagus. The mortality rate after primary fundoplications was 0.04%, whereas the rate after refundoplications was 0.4%, all resulting from an open approach. CONCLUSION: Laparoscopic refundoplications are widely accepted as a treatment option after failed primary antireflux surgery in Austria. However, the conversion rate is 6 times higher and the mortality rate is 10 times higher than for primary antireflux surgery. Therefore, redo fundoplications should be performed only in departments with large experience.

Pharmacokinetics of ethambutol in children and adults with tuberculosis.

SETTING: Five hospitals in the United States. OBJECTIVE: To describe ethambutol pharmacokinetics in children and adults with active tuberculosis (TB). DESIGN: Prospective, open-labeled study in 56 adults and 14 children with active tuberculosis who received ethambutol as part of their multidrug TB regimens. RESULTS: Most serum samples were collected up to 10 h post dose and assayed using a validated gas chromatography assay with mass selective detection (GC/MS). Concentration data were analyzed using non-compartmental and population pharmacokinetic methods. Drug exposure increased with dose, but less than proportionally at doses >3000 mg. Lower than expected maximum serum concentrations (Cmax <2 microg/ml) were common in adults. Very low Cmax (<1 microg/ml) were common in children, as was delayed absorption (time to Cmax >3 h). Many Cmax were at or below typical TB minimal inhibitory concentrations. Cmax values for HIV-positive patients were 20% lower than HIV-negative patients with daily doses, but were similar with larger twice-weekly doses. CONCLUSIONS: Adult TB patients often had lower than expected ethambutol serum concentrations, and most pediatric TB patients had very low ethambutol serum concentrations. Higher doses and therapeutic drug monitoring may be indicated for many of these patients.

Design and validation of a tool for neurite tracing and analysis in fluorescence microscopy images.

BACKGROUND: For the investigation of the molecular mechanisms involved in neurite outgrowth and differentiation, accurate and reproducible segmentation and quantification of neuronal processes are a prerequisite. To facilitate this task, we developed a semiautomatic neurite tracing technique. This article describes the design and validation of the technique. METHODS: The technique was compared to fully manual delineation. Four observers repeatedly traced selected neurites in 20 fluorescence microscopy images of cells in culture, using both methods. Accuracy and reproducibility were determined by comparing the tracings to high-resolution reference tracings, using two error measures. Labor intensiveness was measured in numbers of mouse clicks required. The significance of the results was determined by a Student t-test and by analysis of variance. RESULTS: Both methods slightly underestimated the true neurite length, but the differences were not unanimously significant. The average deviation from the true neurite centerline was a factor 2.6 smaller with the developed technique compared to fully manual tracing. Intraobserver variability in the respective measures was reduced by a factor 6.0 and 23.2. Interobserver variability was reduced by a factor 2.4 and 8.8, respectively, and labor intensiveness by a factor 3.3. CONCLUSIONS: Providing similar accuracy in measuring neurite length, significantly improved accuracy in neurite centerline extraction, and significantly improved reproducibility and reduced labor intensiveness, the developed technique may replace fully manual tracing methods.

[Detection of liver lesions with gadolinium-enhanced VIBE sequence in comparison with SPIO-enhanced MRI]. / Detektion von Leberläsionen mit der Gadolinium-verstärkten VIBE-Sequenz im Vergleich zur SPIO-verstärkten MRT.

PURPOSE: Detection of malignant liver lesions with gadolinium-enhanced volumetric interpolated breath-hold examination (VIBE) in comparison with SPIO-enhanced MRT (four different SPIO-enhanced T2w sequences) and histological and imaging follow-up in non-cirrhotic livers at 1.5 T. PATIENTS AND METHODS: Twenty-two patients with suspected focal liver lesions prospectively underwent a gadolinium-enhanced 3D VIBE. Four T2w sequences (HASTE sequence, fast spin-echo-sequence with and without fat-saturation, FLASH 2D gradient echo-sequence) after administration of superparamagnetic iron oxide (SPIO) served as gold standard combined with histological work-up in 17 patients and histological and imaging follow-up in five patients. The image quality was evaluated and the detectability of intrahepatic lesions was rated by the alternative free-response receiver operating characteristic (AFROC) analysis. In addition, the contrast-to-noise ratio was compared. RESULTS: Altogether 49 malignant and 35 benign liver lesions were found. Concerning the image quality, VIBE turned out to be of slightly poorer image quality than the SPIO-enhanced examination with HASTE sequence (4.95 vs. 5.0). The fast spin-echo-sequence without fat-saturation demonstrated the highest contrast-to-noise ratio. All sequences showed a comparable certainty in detecting lesion (area under the curve 0.68-0.73) and identifying malignant liver lesions. CONCLUSION: Despite the small number of patients, VIBE seems to be a comparable, inexpensive and fast method in diagnosing malignant liver lesions.

Heparanase-1 gene expression in normal, hyperplastic and neoplastic prostatic tissue.

Heparanase-1 (Hpa-1) has been implicated in tumour invasion and metastasis. In the present study, we evaluated the clinicopathological significance of Hpa-1 mRNA expression in prostate cancer and non-cancerous prostatic tissue by one-step polymerase chain reaction (PCR) of laser microdissected prostatic gland cells. In addition, cell type-specific expression of Hpa-1 mRNA in prostatic tissue was analysed by in situ hybridisation. Hpa-1 mRNA expression was found in 50% of normal and 40% of hyperplastic prostatic tissue. In situ hybridisation showed that Hpa-1 mRNA was strongly expressed in prostate gland cells. Of the 26 prostate carcinomas tested, 42% were positive for Hpa-1 mRNA. However, in non-cancerous prostatic tissue, Hpa-1 mRNA was significantly more often expressed than in less differentiated or more invasive prostate cancers (P<0.05). In situ hybridisation revealed only focal Hpa-1 mRNA expression in the neoplastic gland cells. Hpa-1 mRNA expression in the tumours significantly correlated with tumour differentiation and tumour stage (P<0.05). Our data indicate that Hpa-1 gene expression may be lost during dedifferentiation of prostatic gland cells.

Overexpression of the ATP-dependent helicase RecG improves resistance to weak organic acids in Escherichia coli.

Increased resistance to several weak organic acids was conferred on Escherichia coli by overexpression of the ATP-dependent helicase RecG and, to a lesser extent, by overexpressing the helicase RuvAB. This property of helicases was identified by reproducible selection of recG-bearing clones from genomic libraries of the acetate-resistant species Acetobacter aceti and Staphylococcus capitis. We show that overexpression of RecG from both species, but also from E. coli, increased the maximum biomass concentration attained by E. coli cultures that were grown in the presence of various weak organic acids and uncouplers. Furthermore, overexpression of RecG from A. aceti significantly improved the maximum growth rates of E. coli under weak organic acid challenge. Based on the known role of RecG in DNA replication/repair, our data provide a first indication that weak organic acids negatively affect DNA replication and/or repair, and that these negative effects may be counteracted by helicase activity.