TY - JOUR A1 - Jordan, Martin C. A1 - Zimmermann, Christina A1 - Gho, Sheridan A. A1 - Frey, Sönke P. A1 - Blunk, Torsten A1 - Meffert, Rainer H. A1 - Hoelscher-Doht, Stefanie T1 - Biomechanical analysis of different osteosyntheses and the combination with bone substitute in tibial head depression fractures JF - BMC Musculoskeletal Disorders N2 - Background Tibial head depression fractures demand a high level of fracture stabilization to prevent a secondary loss of reduction after surgery. Elderly individuals are at an increased risk of developing these fractures, and biomechanical investigations of the fractures are rare. Therefore, the aim of this study was to systematically analyze different types of osteosyntheses in combination with two commonly used bone substitutes. Methods Lateral tibial head depression fractures were created in synthetic bones. After reduction, the fractures were stabilized with eight different treatment options of osteosynthesis alone or in combination with a bone substitute. Two screws, 4 screws and a lateral buttress plate were investigated. As a bone substitute, two common clinically used calcium phosphate cements, Norian® Drillable and ChronOS™ Inject, were applied. Displacement of the articular fracture fragment (mm) during cyclic loading, stiffness (N/mm) and maximum load (N) in Load-to-Failure tests were measured. Results The three different osteosyntheses (Group 1: 2 screws, group 2: 4 screws, group 3: plate) alone revealed a significantly higher displacement compared to the control group (Group 7: ChronOS™ Inject only) (Group 1, 7 [p < 0.01]; group 2, 7 [p = 0.04]; group 3, 7 [p < 0.01]). However, the osteosyntheses in combination with bone substitute exhibited no differences in displacement compared to the control group. The buttress plate demonstrated a higher normalized maximum load than the 2 and 4 screw osteosynthesis. Comparing the two different bone substitutes to each other, ChronOS™ inject had a significantly higher stiffness and lower displacement than Norian® Drillable. Conclusions The highest biomechanical stability under maximal loading was provided by a buttress plate osteosynthesis. A bone substitute, such as the biomechanically favorable ChronOS™ Inject, is essential to reduce the displacement under lower loading. KW - tibial fracture fixation KW - tibial head fracture KW - biomechanical test KW - static test KW - cyclic test Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-161201 VL - 17 IS - 287 ER - TY - JOUR A1 - Moremi, Nyambura A1 - Claus, Heike A1 - Mshana, Stephen E. T1 - Antimicrobial resistance pattern: a report of microbiological cultures at a tertiary hospital in Tanzania JF - BMC Infectious Diseases N2 - Background Antimicrobial resistance has been declared by the World Health Organization as a threat to the public health. The aim of this study was to analyze antimicrobial resistance patterns of the common pathogens occurring at the Bugando Medical Centre (BMC), Mwanza, Tanzania to provide data for antimicrobial stewardship programmes. Methods A total of 3330 microbiological culture results scripts representing non-repetitive specimens reported between June 2013 and May 2015 were retrieved and analyzed for pathogens and their susceptibility patterns using STATA-11 software. Results Out of 3330 specimens, 439 (13.2%) had positive culture. Staphylococcus aureus (n = 100; 22.8%), Klebsiella pneumoniae (n = 65; 14.8%) and Escherichia coli (n = 41; 9.3%) were the most frequently isolated bacteria. Of 78 Staphylococcus aureus tested, 27 (34.6%) were found to be methicillin resistant Staphylococcus aureus (MRSA). Rates of resistance of Klebsiella pneumoniae and Escherichia coli isolates to third generation cephalosporins were 38.5% (25/65) and 29.3% (12/41) respectively. Staphylococcus aureus and Klesbiella pneumoniae were commonly isolated from bloodstream infections while Escherichia coli and Pseudomonas aeruginosa were the predominant isolates from urinary tract and wounds infections respectively. Of 23 Salmonella species isolated, 22 (95%) were recovered from the blood. Nine of the 23 Salmonella species isolates (39%) were found to be resistant to third generation cephalosporins. The resistance rate of gram-negative bacteria to third generation cephalosporins increased from 26.5% in 2014 to 57.9% in 2015 (p = 0.004) while the rate of MRSA decreased from 41.2% in 2013 to 9.5% in 2015 (p = 0.016). Multidrug-resistant gram-negative isolates were commonly isolated from Intensive Care Units and it was noted that, the majority of invasive infections were due to gram-negative bacteria. Conclusion There is an increase in proportion of gram-negative isolates resistant to third generation cephalosporins. The diversity of potential pathogens resistant to commonly prescribed antibiotics underscores the importance of sustained and standardized antimicrobial resistance surveillance and antibiotic stewardship programmes in developing countries. KW - Tanzania KW - antimicrobial resistance KW - cephalosporin-resistant gram-negative bacteria KW - MRSA Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-161185 VL - 16 IS - 756 ER - TY - JOUR A1 - Diessner, Joachim A1 - Wischnewsky, Manfred A1 - Stüber, Tanja A1 - Stein, Roland A1 - Krockenberger, Mathias A1 - Häusler, Sebastian A1 - Janni, Wolfgang A1 - Kreienberg, Rolf A1 - Blettner, Maria A1 - Schwentner, Lukas A1 - Wöckel, Achim A1 - Bartmann, Catharina T1 - Evaluation of clinical parameters influencing the development of bone metastasis in breast cancer JF - BMC Cancer N2 - Background The development of metastases is a negative prognostic parameter for the clinical outcome of breast cancer. Bone constitutes the first site of distant metastases for many affected women. The purpose of this retrospective multicentre study was to evaluate if and how different variables such as primary tumour stage, biological and histological subtype, age at primary diagnosis, tumour size, the number of affected lymph nodes as well as grading influence the development of bone-only metastases. Methods This retrospective German multicentre study is based on the BRENDA collective and included 9625 patients with primary breast cancer recruited from 1992 to 2008. In this analysis, we investigated a subgroup of 226 patients with bone-only metastases. Association between bone-only relapse and clinico-pathological risk factors was assessed in multivariate models using the tree-building algorithms “exhausted CHAID (Chi-square Automatic Interaction Detectors)” and CART(Classification and Regression Tree), as well as radial basis function networks (RBF-net), feedforward multilayer perceptron networks (MLP) and logistic regression. Results Multivariate analysis demonstrated that breast cancer subtypes have the strongest influence on the development of bone-only metastases (χ2 = 28). 29.9 % of patients with luminal A or luminal B (ABC-patients) and 11.4 % with triple negative BC (TNBC) or HER2-overexpressing tumours had bone-only metastases (p < 0.001). Five different mathematical models confirmed this correlation. The second important risk factor is the age at primary diagnosis. Moreover, BC subcategories influence the overall survival from date of metastatic disease of patients with bone-only metastases. Patients with bone-only metastases and TNBC (p < 0.001; HR = 7.47 (95 % CI: 3.52–15.87) or HER2 overexpressing BC (p = 0.007; HR = 3.04 (95 % CI: 1.36–6.80) have the worst outcome compared to patients with luminal A or luminal B tumours and bone-only metastases. Conclusion The bottom line of different mathematical models is the prior importance of subcategories of breast cancer and the age at primary diagnosis for the appearance of osseous metastases. The primary tumour stage, histological subtype, tumour size, the number of affected lymph nodes, grading and NPI seem to have only a minor influence on the development of bone-only metastases. KW - BRENDA KW - breast cancer KW - bone metastases KW - skeleton KW - breast cancer subtypes Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-161173 VL - 16 IS - 307 ER - TY - JOUR A1 - Stein, Roland Gregor A1 - Wollschläger, Daniel A1 - Kreienberg, Rolf A1 - Janni, Wolfgang A1 - Wischnewsky, Manfred A1 - Diessner, Joachim A1 - Stüber, Tanja A1 - Bartmann, Catharina A1 - Krockenberger, Mathias A1 - Wischhusen, Jörg A1 - Wöckel, Achim A1 - Blettner, Maria A1 - Schwentner, Lukas T1 - The impact of breast cancer biological subtyping on tumor size assessment by ultrasound and mammography - a retrospective multicenter cohort study of 6543 primary breast cancer patients JF - BMC Cancer N2 - Background Mammography and ultrasound are the gold standard imaging techniques for preoperative assessment and for monitoring the efficacy of neoadjuvant chemotherapy in breast cancer. Maximum accuracy in predicting pathological tumor size non-invasively is critical for individualized therapy and surgical planning. We therefore aimed to assess the accuracy of tumor size measurement by ultrasound and mammography in a multicentered health services research study. Methods We retrospectively analyzed data from 6543 patients with unifocal, unilateral primary breast cancer. The maximum tumor diameter was measured by ultrasound and/or mammographic imaging. All measurements were compared to final tumor diameter determined by postoperative histopathological examination. We compared the precision of each imaging method across different patient subgroups as well as the method-specific accuracy in each patient subgroup. Results Overall, the correlation with histology was 0.61 for mammography and 0.60 for ultrasound. Both correlations were higher in pT2 cancers than in pT1 and pT3. Ultrasound as well as mammography revealed a significantly higher correlation with histology in invasive ductal compared to lobular cancers (p < 0.01). For invasive lobular cancers, the mammography showed better correlation with histology than ultrasound (p = 0.01), whereas there was no such advantage for invasive ductal cancers. Ultrasound was significantly superior for HR negative cancers (p < 0.001). HER2/neu positive cancers were also more precisely assessed by ultrasound (p < 0.001). The size of HER2/neu negative cancers could be more accurately predicted by mammography (p < 0.001). Conclusion This multicentered health services research approach demonstrates that predicting tumor size by mammography and ultrasound provides accurate results. Biological tumor features do, however, affect the diagnostic precision. KW - histopathology KW - breast cancer KW - ultrasound KW - mammography KW - tumor size Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-161050 VL - 16 IS - 549 ER - TY - JOUR A1 - Joukhadar, R. A1 - Wöckel, A. A1 - Herr, D. A1 - Paulus, V. A1 - Radosa, J. A1 - Hamza, A. A1 - Solomayer, E. A1 - Baum, S. T1 - Challenges of Longevity: Safety of Vaginal and Laparoscopic Urogynecological Procedures in Septuagenarians and Older Patients JF - BioMed Research International N2 - Introduction. Pelvic organ prolapse (POP) and urinary incontinence (UI) have increasing prevalence in the elderly population. The aim of this study was to compare the comorbidities of these procedures between <70 y/o and ≥70 y/o patients. Materials and Methods. In our retrospective study over a period of 2.5 years, 407 patients had received an urogynecological procedure. All patients with POP were treated by reconstructive surgery. Complications were reported using the standardized classification of Clavien-Dindo (CD). The study can be assigned to stage 2b Exploration IDEAL (Idea, Development, Exploration, Assessment, Long-term study)-system of surgical innovation. Results. Operation time, blood loss, and intraoperative complications have not been more frequent in the elderly, whereas hospital stay was significantly longer in ≥70 y/o patients. Regarding postoperative complications, we noticed that ≥70 y/o patients had an almost threefold risk to develop mild early postoperative complications compared to younger patients (OR: 2.86; 95% CI: 1.76–4.66). On the contrary, major complications were not more frequent. No case of life-threatening complication or the need for blood transfusion was reported. Conclusion. After urogynecological procedures, septuagenarians and older patients are more likely to develop mild postoperative complications but not more intraoperative or severe postoperative complications compared to younger patients. KW - gynecologic surgical procedures/methods KW - postoperative complications/epidemiology KW - vagina/surgery KW - pelvic organ prolapse/surgery KW - middle Aged KW - laparoscopy/methods KW - uterine prolapse/surgery KW - urinary incontinence/surgery KW - surgical Mesh KW - retrospective Studies KW - age factors KW - aged KW - aged 80 and over KW - female KW - reconstructive surgical procedures/methods Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-161005 VL - 2016 IS - Article ID 5184595 ER - TY - JOUR A1 - Zinner, C. A1 - Krueger, M. A1 - Reed, J. L. A1 - Kohl-Bareis, M. A1 - Holmberg, H. C. A1 - Sperlich, B. T1 - Exposure to a combination of heat and hyperoxia during cycling at submaximal intensity does not alter thermoregulatory responses JF - Biology of Sport N2 - In this study, we tested the hypothesis that breathing hyperoxic air (F\(_{in}\)O\(_2\) = 0.40) while exercising in a hot environment exerts negative effects on the total tissue level of haemoglobin concentration (tHb); core (T\(_{core}\)) and skin (T\(_{skin}\)) temperatures; muscle activity; heart rate; blood concentration of lactate; pH; partial pressure of oxygen (P\(_a\)O\(_2\)) and carbon dioxide; arterial oxygen saturation (S\(_a\)O\(_2\)); and perceptual responses. Ten well-trained male athletes cycled at submaximal intensity at 21°C or 33°C in randomized order: first for 20 min while breathing normal air (FinO\(_2\) = 0.21) and then 10 min with F\(_{in}\)O\(_2\) = 0.40 (HOX). At both temperatures, S\(_a\)O\(_2\) and P\(_a\)O\(_2\), but not tHb, were increased by HOX. Tskin and perception of exertion and thermal discomfort were higher at 33°C than 21°C (p < 0.01), but independent of F\(_{in}\)O\(_2\). T\(_{core}\) and muscle activity were the same under all conditions (p > 0.07). Blood lactate and heart rate were higher at 33°C than 21°C. In conclusion, during 30 min of submaximal cycling at 21°C or 33°C, T\(_{core}\), T\(_{skin}\) and T\(_{body}\), tHb, muscle activity and ratings of perceived exertion and thermal discomfort were the same under normoxic and hyperoxic conditions. Accordingly, breathing hyperoxic air (F\(_{in}\)O\(_2\) = 0.40) did not affect thermoregulation under these conditions. KW - heat stress KW - hyperthermia KW - skin blood flow KW - thermoregulation KW - vasoconstriction Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-160993 VL - 33 IS - 1 ER - TY - JOUR A1 - Huang, Guozheng A1 - Schramm, Simon A1 - Heilmann, Jörg A1 - Biedermann, David A1 - Kren, Vladimír A1 - Decker, Michael T1 - Unconventional application of the Mitsunobu reaction: Selective flavonolignan dehydration yielding hydnocarpins JF - Beilstein Journal of Organic Chemistry N2 - Various Mitsunobu conditions were investigated for a series of flavonolignans (silybin A, silybin B, isosilybin A, and silychristin A) to achieve either selective esterification in position C-23 or dehydration in a one-pot reaction yielding the biologically important enantiomers of hydnocarpin D, hydnocarpin and isohydnocarpin, respectively. This represents the only one-pot semi-synthetic method to access these flavonolignans in high yields. KW - Mitsunobu KW - dehydration KW - flavonoid KW - hydnocarpin KW - silybin Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-160986 VL - 12 ER - TY - JOUR A1 - Sawatzky, Edgar A1 - Drakopoulos, Antonios A1 - Rölz, Martin A1 - Sotriffer, Christoph A1 - Engels, Bernd A1 - Decker, Michael T1 - Experimental and theoretical investigations into the stability of cyclic aminals JF - Beilstein Journal of Organic Chemistry N2 - Background: Cyclic aminals are core features of natural products, drug molecules and important synthetic intermediates. Despite their relevance, systematic investigations into their stability towards hydrolysis depending on the pH value are lacking. Results: A set of cyclic aminals was synthesized and their stability quantified by kinetic measurements. Steric and electronic effects were investigated by choosing appropriate groups. Both molecular mechanics (MM) and density functional theory (DFT) based studies were applied to support and explain the results obtained. Rapid decomposition is observed in acidic aqueous media for all cyclic aminals which occurs as a reversible reaction. Electronic effects do not seem relevant with regard to stability, but the magnitude of the conformational energy of the ring system and pK a values of the N-3 nitrogen atom. Conclusion: Cyclic aminals are stable compounds when not exposed to acidic media and their stability is mainly dependent on the conformational energy of the ring system. Therefore, for the preparation and work-up of these valuable synthetic intermediates and natural products, appropriate conditions have to be chosen and for application as drug molecules their sensitivity towards hydrolysis has to be taken into account. KW - quantum mechanics KW - hydrolysis KW - kinetics KW - molecular mechanics KW - natural products Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-160976 VL - 12 ER - TY - JOUR A1 - Schuster, Ann-Christin A1 - Burghardt, Markus A1 - Alfarhan, Ahmed A1 - Bueno, Amauri A1 - Hedrich, Rainer A1 - Leide, Jana A1 - Thomas, Jacob A1 - Riederer, Markus T1 - Effectiveness of cuticular transpiration barriers in a desert plant at controlling water loss at high temperatures JF - AoB Plants N2 - Maintaining the integrity of the cuticular transpiration barrier even at elevated temperatures is of vital importance especially for hot-desert plants. Currently, the temperature dependence of the leaf cuticular water permeability and its relationship with the chemistry of the cuticles are not known for a single desert plant. This study investigates whether (i) the cuticular permeability of a desert plant is lower than that of species from non-desert habitats, (ii) the temperature-dependent increase of permeability is less pronounced than in those species and (iii) whether the susceptibility of the cuticular permeability barrier to high temperatures is related to the amounts or properties of the cutin or the cuticular waxes. We test these questions with Rhazya stricta using the minimum leaf water vapour conductance (gmin) as a proxy for cuticular water permeability. gmin of R. stricta (5.41 × 10\(^{-5}\) m s\(^{-1}\) at 25 °C) is in the upper range of all existing data for woody species from various non-desert habitats. At the same time, in R. stricta, the effect of temperature (15-50 °C) on gmin (2.4-fold) is lower than in all other species (up to 12-fold). Rhazya stricta is also special since the temperature dependence of gmin does not become steeper above a certain transition temperature. For identifying the chemical and physical foundation of this phenomenon, the amounts and the compositions of cuticular waxes and cutin were determined. The leaf cuticular wax (251.4 μg cm\(^{-2}\)) is mainly composed of pentacyclic triterpenoids (85.2% of total wax) while long-chain aliphatics contribute only 3.4%. In comparison with many other species, the triterpenoid-to-cutin ratio of R. stricta (0.63) is high. We propose that the triterpenoids deposited within the cutin matrix restrict the thermal expansion of the polymer and, thus, prevent thermal damage to the highly ordered aliphatic wax barrier even at high temperatures. KW - conductance KW - triterpenoids KW - aliphatic compounds KW - cuticular transpiration KW - cuticular wax KW - cutin KW - desert KW - minimum KW - plant cuticle KW - temperature KW - transition temperature Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-160963 VL - 8 ER - TY - JOUR A1 - Goldmann, Julius A1 - Hornung, Christoph T1 - Interview mit Prof. (em.) Dr. Frank-Rutger Hausmann JF - promptus - Würzburger Beiträge zur Romanistik N2 - Frank-Rutger Hausmann war Professor für Romanische Philologie (Schwerpunkt französische und italienische Literatur) in Freiburg, Aachen und wiederum Freiburg. Hausmann hat sich zudem intensiv mit der Fachgeschichte der deutschen Romanistik und der Geisteswissenschaften allgemein beschäftigt. Für die zweite Ausgabe der promptus-Interviewreihe durften wir ihn nach seiner Perspektive auf die historische und aktuelle Situation der Romanistik befragen. Er arbeitet momentan u.a. an einem Romanistenlexikon, das online veröffentlicht wird, und hat das Romanistenarchiv in Augsburg gegründet. KW - Romanistik KW - Interview KW - aktuelle Situation KW - historische Situation KW - Romansitik KW - Biographisches Interview KW - Perspektive Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-161586 SN - 2510-2613 VL - 2 ER -