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Anabaenopeptins isolated from cyanobacteria were identified as inhibitors of carboxypeptidase TAFIa. Cocrystal structures of these macrocyclic natural product inhibitors in a modified porcine carboxypeptidase B revealed their binding mode and provided the basis for the rational design of small molecule inhibitors with a previously unknown central urea motif. Optimization based on these design concepts allowed for a rapid evaluation of the SAR and delivered potent small molecule inhibitors of TAFIa with a promising overall profile.

The total synthesis of the naturally occurring antibiotic GE81112A, a densely functionalized tetrapeptide, is reported. Comparison of spectral data with those of the natural product and the lack of biological activity of the synthesized compound led us to revise the published configuration of the 3‐hydroxypipecolic acid moiety. This hypothesis was fully validated by the synthesis of the corresponding epimer.

Informations‐ und Kommunikationstechnologien ermoglichen die effiziente, schnelle und sichere Planung und Steuerung von Verwaltungs‐ und Leistungsprozessen in der Instandhaltung. Die systematische Erfassung, Verwaltung und Nutzung administrativer Auftragsdaten kombiniert mit technischen Zeichnungen, Materialeigenschaften und Maschinendaten unterstutzt gezielt die Abwicklung von Instandhaltungsprozessen von der Initiierung bis zum Abschluss des Auftrages. Das vorliegende Kapitel zeigt die Ziele des Einsatzes von IT‐Systemen in der Instandhaltung auf, beschreibt die Elemente und Funktionen von Instandhaltungsplanungs‐ und ‐steuerungssystemen (IPS‐Systeme), befasst sich mit der Nutzung mobiler Systeme und gibt einen Uberblick uber aktuelle und kunftige Entwicklung der Informations‐ und Kommunikationstechnologien in der Instandhaltung.

Dual activation of the glucagon-like peptide 1 (GLP-1) and glucagon receptor has the potential to lead to a novel therapy principle for the treatment of diabesity. Here, we report a series of novel peptides with dual activity on these receptors that were discovered by rational design. On the basis of sequence analysis and structure-based design, structural elements of glucagon were engineered into the selective GLP-1 receptor agonist exendin-4, resulting in hybrid peptides with potent dual GLP-1/glucagon receptor activity. Detailed structure-activity relationship data are shown. Further modifications with unnatural and modified amino acids resulted in novel metabolically stable peptides that demonstrated a significant dose-dependent decrease in blood glucose in chronic studies in diabetic db/db mice and reduced body weight in diet-induced obese (DIO) mice. Structural analysis by NMR spectroscopy confirmed that the peptides maintain an exendin-4-like structure with its characteristic tryptophan-cage fold motif that is responsible for favorable chemical and physical stability.

Etwa 15% der Frauen und 10% der Männer im Alter von über 65 Jahren leiden an einer Harninkontinenz. Die Unterscheidung zwischen einer Drang-, einer Belastungs- und einer Überlaufinkontinenz kann meist durch eine genaue Anamnese erfolgen und ist für die Therapie entscheidend. Die ersten Abklärungsschritte können in der Hausarztpraxis erfolgen, insbesondere der Ausschluss eines Harnwegsinfektes oder einer Überlaufblase. Die Beratung von Patienten über Änderungen der Trinkgewohnheiten und des Miktionsverhaltens sowie die Beratung bezüglich geeigneter Inkontinenzprodukte sind wichtige erste Schritte bei den Therapiemassnahmen. Ebenso können medikamentöse Therapiemassnahmen bereits durch den Grundversorger ergriffen werden. Die therapierefraktäre Harninkontinenz, insbesondere die auf Anticholinergika nicht ansprechende Dranginkontinenz, gehört urologisch abgeklärt, da ein Blasentumor oder andere Erkrankungen der Blase als Ursache vorliegen können.

The structure of the fabclavines-unique mixtures of nonribosomally derived peptide-polyketide hybrids connected to an unusual polyamino moiety-has been solved by detailed NMR and MS methods. These compounds have been identified in two different entomopathogenic Xenorhabdus strains, thereby leading also to the identification of the fabclavine biosynthesis gene cluster. Detailed analysis of these clusters and initial mutagenesis experiments allowed the prediction of a biosynthesis pathway in which the polyamino moiety is derived from an unusual type of fatty acid synthase that is normally involved in formation of polyunsaturated fatty acids. As fabclavines show broad-spectrum activity against bacteria, fungi, and other eukaryotic cells, they might act as "protection factors" against all kinds of food competitors during the complex life cycle of Xenorhabdus, its nematode host, and their insect prey.

During the search for novel natural products from entomopathogenic Xenorhabdus doucetiae DSM17909 and X. mauleonii DSM17908 novel peptides named xenoamicins were identified in addition to the already known antibiotics xenocoumacin and xenorhabdin. Xenoamicins are acylated tridecadepsipeptides consisting of mainly hydrophobic amino acids. The main derivative xenoamicin A (1) was isolated from X. mauleonii DSM17908, and its structure elucidated by detailed 1D and 2D NMR experiments. Detailed MS experiments, also in combination with labeling experiments, confirmed the determined structure and allowed structure elucidation of additional derivatives. Moreover, the xenoamicin biosynthesis gene cluster was identified and analyzed in X. doucetiae DSM17909, and its participation in xenoamicin biosynthesis was confirmed by mutagenesis. Advanced Marfey's analysis of 1 showed that the absolute configuration of the amino acids is in agreement with the predicted stereochemistry deduced from the nonribosomal peptide synthetase XabABCD. Biological testing revealed activity of 1 against Plasmodium falciparum and other neglected tropical diseases but no antibacterial activity.

Die urethrale Anastomose stellt beim extrakorporalen orthotopen Blasenersatz nach roboter­assistierter radikaler Zystektomie (RARC) eine besondere Herausforderung dar. Prinzipiell kann sie mit vorgelegten Einzelnahten oder fortlaufend robotisch genaht werden. Derzeit werden in der Literatur die unterschiedlichen Techniken meist nur andeutungsweise erwahnt. In der vorliegenden Arbeit wird je ein Beispiel beider Techniken detailliert beschrieben und es werden ihre Vor- und Nachteile diskutiert.

Griselimycin (GM) and methylgriselimycin (MGM), naturally produced by microorganisms of the genus Streptomyces, are cyclic depsipeptides composed of ten amino acids. They exhibit antibacterial activity against mycobacterium species by inhibiting the sliding clamp of prokaryotic DNA polymerase III and are therefore considered as potential anti-tuberculosis drugs. The difference between both peptides is the presence of L -(R)-4-methylproline in MGM instead of L -proline in GM at position 8 of the amino acid sequence. Methylation increases both metabolic stability and activity of MGM compared to GM. To get deeper insight into the structure-activity relationship we determined the solution structure of the cyclic part of methylgriselimycin using rotating frame nuclear Overhauser effect (ROE) distance restraints and residual dipolar couplings (RDC). The structure of methylgriselimycin in solution is compared to the structure of griselimycin in a co-crystal with DNA polymerase III subunit beta. As a result a highly defined structural model of methylgriselimycin is obtained which shows related characteristics to the bound griselimycin.

Mature thrombin activatable fibrinolysis inhibitor (TAFIa) is a carboxypeptidase that stabilizes fibrin clots by removing C-terminal arginines and lysines from partially degraded fibrin. Inhibition of TAFIa stimulates the degradation of fibrin clots and may help to prevent thrombosis. Applying a lead finding approach based on literature-mining, we discovered that anabaenopeptins, cyclic peptides produced by cyanobacteria, were potent inhibitors of TAFIa with IC50 values as low as 1.5 nM. We describe the isolation and structure elucidation of 20 anabaenopeptins, including 13 novel congeners, as well as their pronounced structure-activity relationships (SAR) with respect to inhibition of TAFIa. Crystal structures of the anabaenopeptins B, C and F bound to the surrogate protease carboxypeptidase B revealed the binding modes of these large (~850 Da) compounds in detail and explained the observed SAR, i.e. the strong dependence of the potency on a basic (Arg, Lys) exocyclic residue that addressed the S1’ binding pocket, and a broad tolerance towards substitutions in the pentacyclic ring that acted as a plug of the active site.

In an antibiotic lead discovery program, the known strain Streptomyces armeniacus DSM19369 has been found to produce three new natural products when cultivated on a malt-containing medium. The challenging structural elucidation of the isolated compounds was achieved by using three independent methods, that is, chemical degradation followed by NMR spectroscopy, a computer-assisted structure prediction algorithm, and X-ray crystallography. The compounds, named armeniaspirol A-C (2-4), exhibit a compact, hitherto unprecedented chlorinated spiro[4.4]non-8-ene scaffold. Labeling experiments with [1-(13)C] acetate, [1,2-(13)C2] acetate, and [U-(13)C] proline suggest a biosynthesis through a rare two-chain mechanism. Armeniaspirols displayed moderate to high in vitro activities against gram-positive pathogens such as methicillin-resistant S. aureus (MRSA) or vancomycin resistant E. faecium (VRE). As analogue 2 was active in vivo in an MRSA sepsis model, and showed no development of resistance in a serial passaging experiment, it represents a new antibiotic lead structure.

Nach roboterassistierter radikaler Zystektomie (RARC) und extrakorporaler Rekonstruktion werden zur urethroneovesikalen Anastomose beim orthotopen Blasenersatz robotisch fortlaufend genahte Techniken und solche mit offen oder robotisch vorlegten Einzelknopffaden verwendet. In einer online Umfrage wurde an 62 deutschsprachigen Robotikzentren erfragt, ob an den jeweilige Zentren RARCs durchfuhrt werden. Wurde die Frage bejaht, wurden weitere Fragen zur Art des Blasenersatzes und zur Technik der urethroneovesikalen Anastomose gestellt. Die Rucklaufquote der online Fragebogen lag bei 80% (n=50). 44% (n=22) der Zentren mit Ruckantwort gaben an, die RARC durchzufuhren. Der Umfrage zu folge berichteten alle Zentren bis auf eins, die Rekonstruktion der Neoblase extrakorporal durchzufuhren [Studerblase 73% (n=16), Hautmannblase 18% (n=4) und andere 9% (n=2)]. Nach Rekonstruktion der Neoblase gaben 36% (n=8) der Robotikteams an, die Anastomose mit offen operativ vorgelegten, 24% (n=5) die Anastomose mit robotisch vorgelegten Einzelfaden zu knoten und 40% (n=9) sie fortlaufend robotisch nach Neuandocken des Roboterstativs oder im Rahmen der intrakorporalen Rekonstruktion zu nahen. Nach der vorliegenden Umfrage werden im deutschsprachigen Raum nach extrakorporaler Rekonstruktion meist mit einer Studer Blase am haufigsten Anastomosentechniken mit vorgelegten Einzelknopfnahten verwendet. Diese bieten den Vorteil, dass auf ein Neuandocken des Roboters verzichtet werden kann. Allerdings muss uber die Laparotomie genugend Platz zum offenen Knoten der Anastomose vorhanden sein.

Robotic-assisted radical prostatectomy (RARP) is feasible using either an extraperitoneal (EP) or a transperitoneal (TP) approach. This study reports on the experience of a single hospital using both techniques.From July 2009 to March 2011, 170 patients underwent RARP. EP was chosen in 103 patients and TP in 67. TP was preferred in cases previous mesh hernia repair or if extended lymph-node dissection (LND) was considered necessary. Otherwise, EP was performed; it was preferred in cases of obesity (body mass index (BMI)30 kg/m(2)) or previous intra-abdominal surgery.There were no significant differences in preoperative mean age (64.4 vs 65.6 years), BMI (26.5 vs 26.3 kg/m(2)) or prostate size (51.8 vs 55.8 cm(3)) between EP and TP patients. Owing to preoperative selection criteria, prostate-specific antigen levels and the average Gleason score were significantly lower in EP than in TP patients (p0.001). Whereas access time and time for anastomosis did not differ significantly (21 vs 19 min, p = 0.11, and 26 vs 24 min, p = 0.36, respectively), overall surgical time was significantly longer in TP (225 vs 191 min, p0.001). Blood loss was equal in both groups (EP 276 vs TP 281 ml, p = 0.88). Complication rates were lower in EP (n = 7, 6.8% vs n = 8, 12%, p = 0.024). Time until first defecation and last analgesic treatment were significantly shorter in EP (p0.05).The results of the current evaluation underline the clinical advantages of an extraperitoneal approach for RARP. However, a transperitoneal approach is still considered necessary for extended LND or special clinical conditions. Robotic teams should be trained using both approaches.

Die Babesiose ist eine durch Protozoen hervorgerufene Erkrankung bei Tieren, die durch Zecken auch auf Menschen ubertragen werden kann. Erkrankungen beim Menschen wurden weltweit beschrieben und treten vor allem in Nordamerika, vereinzelt aber auch in Europa auf. Das Krankheitsspektrum reicht von grippeartigen Symptomen bis zu einem malariaahnlichen Syndrom. Bei Patienten mit Splenektomie und/oder Immunsuppression sind schwere, auch todliche Verlaufe bekannt. Ein 63-jahriger Patient mit Zustand nach Splenektomie und Rituximabtherapie bei B-Zell-Lymphom wurde wegen Anamie, Thrombozytopenie, Subikterus, dunklen Urins und Infektzeichen aufgenommen. Laborchemisch zeigten sich eine normochrome Anamie mit positiven Hamolyseparametern und eine Hamoglobinurie mit beginnender Niereninsuffizienz. Im Blutausstrich waren plasmodienahnliche intraerythrozytare Erreger nachweisbar. Es ergaben sich keine Hinweise fur eine Malariaexposition. Der Patient war haufig in den Waldern der Hegau-Bodensee-Region unterwegs, einem bekannten Zeckengebiet. Es wurde die Diagnose einer Babesiose gestellt und mit Polymerase-Kettenreaktion bestatigt. Der Erreger wurde als Babesia EU1 klassifiziert. Die Behandlung mit Clindamycin und Chinin fuhrte nach 4 Wochen zur Remission. Kurz danach trat ein Rezidiv auf, und es wurde eine Langzeittherapie mit Atovaquon und Azithromycin begonnen. Nach mehreren Monaten kam es zur Serokonversion, und die Elimination der Erreger erfolgte schlieslich 8 Monate nach Krankheitsbeginn. Auch in Deutschland ist mit dem Auftreten von Babesiose beim Menschen zu rechnen. Bei Patienten mit Infektzeichen und hamolytischer Anamie muss an eine Babesiose gedacht werden, besonders wenn sie splenektomiert und/oder immunsupprimiert sind.

A new fossil species of Electrocrania Kusnezov is described, i.e. Electrocrania michalskii sp. nov. The male moth in Baltic amber is in a sufficiently good condition to allow its assignment to the family Micropterigidae on the basis of four re-cognized autapomorphies of this family (Kristensen 1998). The unique venation of the specimen places it in the genus Electrocrania stat. rev. and allows a redescription of that genus that has recently been treated as synonym of Micropterix Hübner. It is argued that Electrocrania is a distinct genus within Micropterigidae that is not associated with Micropterix, but probably can be assigned to the "Northern Hemisphere genera"-lineage of Micropterigidae.

The discovery of Streptomyces-produced streptomycin founded the age of tuberculosis therapy. Despite the subsequent development of a curative regimen for this disease, tuberculosis remains a worldwide problem, and the emergence of multidrug-resistant Mycobacterium tuberculosis has prioritized the need for new drugs. Here we show that new optimized derivatives from Streptomyces-derived griselimycin are highly active against M. tuberculosis, both in vitro and in vivo, by inhibiting the DNA polymerase sliding clamp DnaN. We discovered that resistance to griselimycins, occurring at very low frequency, is associated with amplification of a chromosomal segment containing dnaN, as well as the ori site. Our results demonstrate that griselimycins have high translational potential for tuberculosis treatment, validate DnaN as an antimicrobial target, and capture the process of antibiotic pressure-induced gene amplification.

During the screening program for new antibacterial agents produced by actinomycetes, GE23077 was isolated from fermentation broths of an Actinomadura sp. strain as a complex of factors A1, A2, B1, B2. NMR, MS and GC/MS analysis carried out on the isolated components led to the conclusion that GE23077 is a novel cyclic heptapeptide consisting of common and unusual amino acids. The chemical structures of the complex components were elucidated. Components A and B differ in the structure of the acyl group connected to a 2,3-diaminopropanoic acid moiety. A alpha-amino-malonic acid residue in the peptidic sequence is the origin of an isomerization process between A1 and A2 as well as B1 and B2. The chirality of the alpha-amino-malonic acid residue can be inverted easily via keto-enol tautomerism. Factors A2 and B2 should be considered as epimers of A1 and B1 respectively. By degradation studies the absolute configuration of some amino acids were determined. Chiral GC-MS and Micellar Electrokinetic Capillary Chromatography (MEKC) were used to define the absolute stereochemistries of five out of ten chiral centers.

GE 23077 factors A1, A2, B1 and B2 are novel antibiotics isolated from fermentation broths of an Actinomadura sp. strain. GE23077 antibiotics are cyclic peptides, which inhibit Escherichia coli RNA polymerase at nM concentrations. Both rifampicin-sensitive and rifampicin-resistant polymerases are inhibited, whereas E. coli DNA polymerase and wheat germ RNA polymerase are substantially not affected. In spite of the potent activity on the enzyme, the antibiotics generally show poor activity against whole cell bacteria. The spectrum of activity is restricted to Moraxella catarrhalis, including clinical isolates, with partial activity against Neisseria gonorrhoeae and Mycobacterium smegmatis.

Ustilago species produce an extracellular oil that shows activity in various pharmaceutical assays. We isolated several complexes of this heterogeneous glycolipid from cultures of Ustilago maydis DSM 11494 and Geotrichum candidum ST 002515, and determined the chemical structures of these new compounds, termed ustilipids, on the basis of NMR experiments, mass spectra, and fatty acid analyses. They all possess a 4-O-beta-D-mannopyranosyl D-erythritol basic framework, the configuration of which was confirmed, after initial solvolysis, by a single-crystal X-ray structure analysis. All the investigated ustilipids and related compounds are similarly constructed: the three hydroxy groups of the erythritol side chain are free in all cases, whereas the hydroxy groups of the mannose residue are for the most part acylated. Medium-chain fatty acids have for the first time been detected as components of glycolipids produced by Ustilaginales. While the 2-hydroxy group of the mannose residue is esterified with a C2-C8 carboxylate side chain, the 3-hydroxy group is in all cases esterified by a longer, C12-C20 fatty acid residue. The oxygen functionalities at the 4 and 6 positions are either acetylated or present as free hydroxy groups. Ustilipids antagonize dopamine D3 receptors in micromolar quantities; other members of this class of compounds have been found to possess an inhibitory action on the neurotensin receptor. The hemolytic activity of ustilipids is low.

Bile acids are generated in vivo from cholesterol in the liver, and they undergo an enterohepatic circulation involving the small intestine, liver, and kidney. To understand the molecular mechanism of this transportation, it is essential to gain insight into the three-dimensional (3D) structures of proteins involved in the bile acid recycling in free and complexed form and to compare them with homologous members of this protein family. Here we report the solution structure of the human ileal lipid-binding protein (ILBP) in free form and in complex with cholyltaurine. Both structures are compared with a previously published structure of the porcine ILBP-cholylglycine complex and with related lipid-binding proteins. Protein structures were determined in solution by using two-dimensional (2D)- and 3D-homo and heteronuclear NMR techniques, leading to an almost complete resonance assignment and a significant number of distance constraints for distance geometry and restrained molecular dynamics simulations. The identification of several intermolecular distance constraints unambiguously determines the cholyltaurine-binding site. The bile acid is deeply buried within ILBP with its flexible side-chain situated close to the fatty acid portal as entry region into the inner ILBP core. This binding mode differs significantly from the orientation of cholylglycine in porcine ILBP. A detailed analysis using the GRID/CPCA strategy reveals differences in favorable interactions between protein-binding sites and potential ligands. This characterization will allow for the rational design of potential inhibitors for this relevant system.

About 15% of the women and 10% of the men past the age of 65 years suffer from urinary incontinence. In most cases, accurate history taking can help differentiate between urge incontinence, stress incontinence and overflow incontinence, and is essential in choosing the appropriate treatment. Initial diagnostic testing can be conducted by the general practitioner, especially tests to exclude urinary tract infections or to rule out an overactive bladder. Patient education on changes to fluid intake and voiding habits as well as advice on suitable incontinence products are important first steps in the management of urinary continence. Also, drug treatment can be initiated in general practice. Patients with refractory urinary incontinence, particularly those who did not respond to anticholinergic medication, should be referred to a urologist for further evaluation since there may be an underlying tumour or other disorder of the bladder that is causing the incontinence.Etwa 15% der Frauen und 10% der Männer im Alter von über 65 Jahren leiden an einer Harninkontinenz. Die Unterscheidung zwischen einer Drang-, einer Belastungs- und einer Überlaufinkontinenz kann meist durch eine genaue Anamnese erfolgen und ist für die Therapie entscheidend. Die ersten Abklärungsschritte können in der Hausarztpraxis erfolgen, insbesondere der Ausschluss eines Harnwegsinfektes oder einer Überlaufblase. Die Beratung von Patienten über Änderungen der Trinkgewohnheiten und des Miktionsverhaltens sowie die Beratung bezüglich geeigneter Inkontinenzprodukte sind wichtige erste Schritte bei den Therapiemassnahmen. Ebenso können medikamentöse Therapiemassnahmen bereits durch den Grundversorger ergriffen werden. Die therapierefraktäre Harninkontinenz, insbesondere die auf Anticholinergika nicht ansprechende Dranginkontinenz, gehört urologisch abgeklärt, da ein Blasentumor oder andere Erkrankungen der Blase als Ursache vorliegen können.Environ 15% des femmes et 10% des hommes âgée de plus de de 65 ans souffrent d'incontinence urinaire. Dans le plupart des cas, une anamnèse soigneuse peut aider à différencier entre l'incontinence par impériosité, l'incontinence de stress et l'incontinence par regorgement, ce qui est essentiel pour choisir le traitement approprié. L'évaluation diagnostique initiale peut être effectuée par le médecin généraliste, en particulier les tests pour exclure une infection urinaire ou une incontinence par regorgement. L'éducation des malades visant à changer les habitudes de prise liquidienne et d'uriner, ainsi qu'à conseiller des produits appropriés à l'incontinence représente une importante première étape dans la prise en charge de ce problème. Le traitement médicamenteux peut également être instauré en pratique générale. Les malades ayant une incontinence urinaire réfractaire, en particulier ceux qui ne répondent pas à un anticholinergique, devraient être référés à un urologue pour étendre les investigations puisqu'une tumeur sous-jacente ou une autre anomalie de la vessie peut être responsable de l'incontinence.

A new class of four depsipentapeptides called chaiyaphumines A-D (1-4) was isolated from Xenorhabdus sp. PB61.4. Their structures were elucidated by detailed 1D and 2D NMR experiments and by a Marfey's analysis following flash hydrolysis of the peptide. Verification of the structure was achieved by three-dimensional modeling using NOE-derived distance constraints, molecular dynamics, and energy minimization. Chaiyaphumine A (1) showed good activity against Plasmodium falciparum (IC50 of 0.61 μM), the causative agent of malaria, and was active against other protozoal tropical disease causing agents.

International audience; The high diastereoselectivity of the hydrogenation of artemisinate by diazene to form dihydroartemisinate (diastereoselective ratio, dr, 97:3) necessary for efficient production of artemisin has been rationalized by state-of-the-art DFT calculations and identification of the noncovalent interactions by coupled ELF/NCI analysis. Remarkably, a single conformer of artemisinate is responsible for the high diastereoselectivity of the reaction. NMR studies confirm the preference for a single conformation that is found to be identical to that predicted by the calculations. The calculations and ELF/NCI analyses show that the hydrogenation of the exocyclic activated C═C double bond has a low energy barrier and that the lowest transition state and the preferred conformation of free artemisinate develop the same network of weak noncovalent interactions between the electron donor groups (oxygen and exocyclic C═C double bond) and CH bonds of the cis-decalene group of the artemisinate, which rationalize the high diastereoselectivity unusual for a strongly exothermic reaction.

The ileal lipid-binding protein (ILBP) is the only physiologically relevant bile acid-binding protein in the cytosol of ileocytes. To identify the bile acid-binding site(s) of ILBP, recombinant rabbit ILBP photolabeled with 3-azi- and 7-azi-derivatives of cholyltaurine was analyzed by a combination of enzymatic fragmentation, gel electrophoresis, and matrix-assisted laser desorption ionization (MALDI)-mass spectrometry. The attachment site of the 3-position of cholyltaurine was localized to the amino acid triplet His(100)-Thr(101)-Ser(102) using the photoreactive 3,3-azo-derivative of cholyltaurine. With the corresponding 7,7-azo-derivative, the attachment point of the 7-position could be localized to the C-terminal part (position 112-128) as well as to the N-terminal part suggesting more than one binding site for bile acids. By chemical modification and NMR structure of ILBP, arginine residue 122 was identified as the probable contact point for the negatively charged side chain of cholyltaurine. Consequently, bile acids bind to ILBP with the steroid nucleus deep inside the protein cavity and the negatively charged side chain near the entry portal. The combination of photoaffinity labeling, enzymatic fragmentation, MALDI-mass spectrometry, and NMR structure was successfully used to determine the topology of bile acid binding to ILBP.

The aim of the present study was the synthesis of phospholipids containing a drug molecule instead of a fatty acid. Valproic acid and ibuprofen served as model compounds. The target molecules were synthesized either starting from sn-glycero-3-phosphocholine (1) or using (S)-2-O-benzyl-1-O-tritylglycerol (11) and (R)-2-O-benzyl-1-O-tert-butyldiphenylsilylglycerol (12), respectively, as key intermediates. With respect to the surface properties and the aggregation behavior, the drug–phospholipid conjugates resembled natural phosopholipids. Upon incubation with porcine pancreatic phospholipase A2, only compounds with a fatty acid in the sn-2 position of the glycerol backbone were degraded. Derivatives with either ibuprofen in the sn-2 position or displaying the unnatural S-configuration were resistant to enzymatic in vitro hydrolysis.

The conformation of the ionophore−metal complex between salinomycin and sodium was determined in solid state and in solution using X-ray single-crystal structure analysis and a combined approach of 2D-NMR spectroscopy with restrained simulated annealing calculations. The solution structure of the salinomycin−Na complex was studied in two different solvents (DMSO-d6 and CDCl3) in order to focus on conformational differences in various molecular environments. The X-ray structure of the complexed salinomycin is characterized by two separate conformers found in the asymmetric unit with a similar coordination of the central sodium ion buried in the interior, hydrophilic region of this ionophore. A quasi-macrocyclic core structure is stabilized by numerous metal−oxygen electrostatic interactions and by an intramolecular head-to-tail hydrogen bond. The NMR structure in CDCl3 is very similar to those two conformations in the solid state, while the structure in DMSO differs significantly. It could be demonstrated ...

The first three-dimensional structure of moenomycin A in aqueous solution based on NMR-derived distance constraints and molecular dynamics simulations is presented. The antibiotic moenomycin A was obtained from the FlavomycinR complex by ultrafiltration, chromatography on a DEAE-cellulose ion exchanger and reverse-phase chromatography in 98 % purity. In contrast to the previously reported behaviour, the compound gave rise to well-resolved NMR spectra in standard solvents. Using several two-dimensional experiments, a complete assignment of proton and carbon chemical shifts was achieved in (CD3)2SO, CD3OD and H2O/D2O (9 : 1, pH 7.3). A total of 175 interproton distances were determined from 600-MHz rotating-frame NOE (ROE) spectra and were used as restraints in molecular dynamics calculations. These restraints included 84 ROEs between protons of the moenocinol part leading to a very well-defined structure of the lipid part of the molecule. The relative orientation of the subunits was determined by 66 ROEs among different sugar rings and between the sugar rings and moenocinol. As a result of the molecular dynamics calculation, rings D, E, and F as well as the moenocinol part are very well-defined (average rms deviation over all heavy atoms 0.48 A) whereas rings A, B and C display a higher degree of conformational flexibility which might be an artefact due to the lower number of ROEs in this part of the molecule. A three-dimensional pharmacophore hypothesis comprising functional groups of rings E and F and the carboxyl group of glyceric acid is presented on the basis of the degradation and derivatization studies of Welzel and coworkers [Welzel, P., Kunisch, F., Kruggel, F., Stein, H., Scherkenbeck, J., Hiltmann, A., Duddeck, H., Muller, D., Maggio, J. E., Fehlhaber, H.-W., Seibert, G., van Heijenoort, Y. & van Heijenoort, J. (1987) Moenomycin A : Minimum structural requirements for biological activity, Tetrahedron 43, 585−598; Welzel, P. (1993) Transglycosylase inhibition, in Antibiotics and antiviral compounds − Chemical synthesis and modifications (Krohn, K., Kirst, H. A. & Maag, H., eds) pp. 373−378, VCH Weinheim].

Controlled acid hydrolysis of compound 2 resulted in the selective opening of the macrocycle while in basic condition a retro-aldol reaction occurred at the level of phenylserine thiazole. Compound 2 can be easily prepared from the natural antibiotic MDL 62,879. All the compounds prepared resulted less active than MDL 62,879.

The complex between the glycopeptide MDL 62,346 and the model cell wall analog Ac2-Lys-d-Ala-d-Ala was studied by NMR spectroscopy in DMSO solution. A complete assignment of proton and carbon reson...

The 3D structure of ramoplanin was studied by NMR spectroscopy in aqueous solution. A total of 320 interproton distances were determined from a NOESY spectrum and were used as restraints in distance geometry calculations. A structural refinement was carried out by molecular dynamics calculations in a solvent box. The structure of ramoplanin is characterized by two antiparallel beta-strands which are formed by the residues 2-7 and 10-14, respectively. The beta-strands are connected by six intramolecular hydrogen bonds and a reverse beta-turn which is formed by Thr8 and Phe9 (in positions i+1 and i+2, respectively). Residues 2 and 14 are connected by a loop consisting of Leu15, Ala16, Chp17, and the side chain of Asn2. Although residues 14-17 show the formation of a beta-turn, only the N-terminal end of the turn is directly connected to one of the beta-strands (Gly14), whereas the C-terminal end (Chp17) is linked via the side chain of Asn2. The 3D conformation of ramoplanin is also stabilized by a hydrophobic cluster of the aromatic sidechains of the residues 3, 9, and 17. This hydrophobic collapse leads to a U-shaped topology of the beta-shee: with the beta-turn at one end and the loop at the other end. The structure found for ramoplanin differs corsiderably from the published structure of ramoplanose which might be due to a smaller number of NOE distance restraints used in the previous study.

Vesicovaginal fistulae have always been a highly problematic complication. Nowadays, most cases are complications after hysterectomy or obstetric surgery, whereas obstructed labour is the main aetiology in underdeveloped countries. The localisations and dimensions of the fistulae are very different dependent on their aetiology. Obstructed labour leads to necrosis of the anterior vaginal wall and consequently to a lower, urethrovaginal, vesicovaginal or combined fistula. After hysterectomy, we know that fistulae occur in about 1/1,800 cases. At a rate of 600,000 hysterectomies in the United States in 2003, we can assume approximately 330 fistulae had to be treated in that year. This makes it not only a social but also an economic issue. These fistulae are usually found to be supratrigonal and sometimes located high on the bladder dome. This fact makes it very demanding or even impossible to operate transvaginally. They occur after inadvertent lesion of the bladder or ureters, operation-site infection or tumourous diseases. The success rate of either repair is between 75 and 97 % depending on the method and complexity. Smaller fistulae can be treated by transurethral drainage and sometimes by transurethral coagulation of the bladder wall, depending on their aetiology. However, the long-term results are not very impressive (7–12.5 %). A valuable alternative to conservative treatment is the use of fibrin glue. In case of failure, the operative access is still available.

Fragments of the thiopeptide antibiotic MDL 62,879 (GE2270A) were prepared under mild degradation conditions. Their structures were determined by spectroscopic techniques and by comparison to synthetic reference thiazolyl dipeptides. The two thiazolyl amino acids have stereocenters with S configurations and their sequence is reversed with respect to the structure previously proposed for MDL 62,879.

A series of amide derivatives of natural glycopeptide A-40,926 (A), its 6B-methyl ester (MA) and 6B-decarboxy-6B-hydroxymethyl derivative (RA) were prepared with the aim of obtaining activity against glycopeptide-resistant enterococci. These compounds are structurally related to a class of amides of 34-de(acetylglucosaminyl)-34-deoxy teicoplanin which showed interesting activity against strains of Enterococcus faecalis and E. faecium highly resistant to both vancomycin and teicoplanin. Among them, RA-amides MDL 63,246 and MDL 63,042 were the most active derivatives against several Gram-positive bacteria, including VanB and VanC enterococci, and were moderately active (MIC range 0.5 approximately 64 micrograms/ml) against strains of Enterococcus for which vancomycin and teicoplanin MICs were > or = 128 micrograms/ml. The chemical rationale and the synthesis of these new series of glycopeptide derivatives are described. Preliminary in vitro data are reported and structure-activity relationships are discussed.

To prospectively compare the AirSeal® System valve-less Trocar with a standard Versaport™ Plus V2 Trocar as assistant insufflating port in transperitoneal and extraperitoneal robotic-assisted radical prostatectomy (t-RARP/e-RARP).Two consecutive cohorts of patients undergoing RARP using either a 12 mm AirSeal valve-less Trocar (n=19 [14 t-RARP/5 e-RARP]) or a 12 mm Versaport Plus V2 Trocar (n=17 [11 t-RARP/6 e-RARP]) were prospectively evaluated. Age, body mass index, tumor characteristics, and surgical approach were similar in both cohorts. Besides relevant clinical data, episodes of pressure loss (8 mm Hg), the number of necessary trocar manipulations, the frequency of camera cleaning, and overall carbon dioxide (CO2) consumption were recorded and compared.Mean surgical time was 175 minutes in the AirSeal and 166 minutes in the Versaport group (p=0.55). Whereas in the AirSeal group, only one episode of pressure loss8 mm Hg was observed; this occurred in mean 38 times in the Versaport group (p0.0001). No trocar manipulations for specimen or needle retrieval were necessary in the AirSeal group in contrast to in mean 15 in the Versaport group (p0.0001). Otherwise, no appreciable differences regarding overall operating time, blood loss, camera cleaning, or overall CO2 consumption were observed for the present study. Patient CO2 absorption was not evaluated.In the present study, the AirSeal Trocar offered a more stable pneumocavity and facilitated specimen retrieval and needle extraction.

To compare pre- and postoperative urodynamic findings in patients with a bulbourethral composite suspension and intraoperative urodynamically controlled sling tension adjustment.All data were prospectively collected from 10 patients (mean age 66 years) who successfully underwent bulbourethral composite suspension for moderate to severe postprostatectomy incontinence. Patients were evaluated preoperatively and 3-6 months postoperatively by urodynamic measurements, including urethra pressure profiles (UPPs) and pressure flow studies (PFSs). Clinical outcome was evaluated by patient-reported pad use and questionnaires (ICIQ-UI SF and I-QOL). Intraoperatively sling tension was adjusted under repeated urodynamic measurements of abdominal leak point pressure. Data were evaluated using the Kruskal-Wallis Wilcoxon test.Sling implantation was successful in all patients. Pre- to postoperative pad use decreased significantly (P.005). Five patients were pad-free, 3 used 1 pad, and 2 used 2 pads per day. Continence and quality of life improved significantly (ICIQ-UI SF: pre-op 17 vs post-op 4.9; I-QOL: pre-op 66 vs post-op 91; P.05 for both). Urodynamic parameters during the filling phase remained unchanged. UPPs revealed a significant increase of the maximal urethral closure pressure (pre-op 40 cm H(2)O vs post-op 58 cm H(2)O) and functional length (pre-op 31 mm vs post-op 40 mm; P.05 for both). Postoperatively, urodynamic maximal flow rates were slightly reduced from 16 mL/s to 12 mL/s (P = .4). PFSs revealed an unobstructed voiding in all patients.According to the present evaluation, a bulbourethral composite suspension with intraoperative urodynamically controlled sling tension adjustment improves continence without causing prolonged clinically or urodynamically significant voiding obstruction.

Caffeine, widely consumed in beverages, is known to alter several biliary parameters that can affect gallstone pathogenesis. To address the question whether methylxanthines can act on the luminal side of biliary epithelial cells, we measured caffeine and its primary demethylation products in human bile. Eight patients had an external biliary drainage due to bile duct or gallbladder disease. Two of the patients suffered from histologically confirmed liver cirrhosis. The levels of caffeine, paraxanthine, theobromine, and theophylline were monitored over 10 h in plasma and bile before and after a prior oral dose of caffeine (5 mg/kg b. wt.). Methylxanthines were enriched by an organic extraction procedure and separated by reversed-phase high-performance liquid chromatography. Time-concentration curves in bile paralleled the time-course of methylxanthine levels in blood plasma. Accordingly, values in bile and blood plasma were highly correlated for each methylxanthine measured. Within 1 h after the oral test dose, peak levels of caffeine were obtained in both fluids. Biliary concentrations were either almost equal (caffeine) or lower (dimethylxanthines) than their respective values in blood plasma. The results of our study indicate that minor amounts of caffeine and its primary degradation products are excreted via the bile allowing local interference with epithelial cell metabolism of bile ducts and gallbladder.

The conformation of the ionophore−metal complex between salinomycin and sodium was determined in solid state and in solution using X-ray single-crystal structure analysis and a combined approach of 2D-NMR spectroscopy with restrained simulated annealing calculations. The solution structure of the salinomycin−Na complex was studied in two different solvents (DMSO-d6 and CDCl3) in order to focus on conformational differences in various molecular environments. The X-ray structure of the complexed salinomycin is characterized by two separate conformers found in the asymmetric unit with a similar coordination of the central sodium ion buried in the interior, hydrophilic region of this ionophore. A quasi-macrocyclic core structure is stabilized by numerous metal−oxygen electrostatic interactions and by an intramolecular head-to-tail hydrogen bond. The NMR structure in CDCl3 is very similar to those two conformations in the solid state, while the structure in DMSO differs significantly. It could be demonstrated ...

New antifungal antibiotics, designated as 3874 H1 and H3, were discovered in the fermentation broth of the strain Streptomyces sp. HAG 003874. The compounds were obtained as yellow powders after sequential purification by chromatography on MCI Gel CHP20P, Fractogel HW-40 and ODS reversed phase chromatography. On the basis of the results of spectroscopic analysis, it was found that 3874 H1, C58H86N2O18, MW 1098, belongs to the p-aminoacetophenone containing family of heptaene antibiotics, while 3874 H3, C57H87NO18, MW 1073, is a non-aromatic heptaene. In addition to these, a minor component, 3874 H2, C59H88N2O18, MW 1112, a N-methyl derivative of 3874 H1 has been detected. The structures were elucidated through mass spectral analyses and 1-D and 2-D homonuclear and heteronuclear NMR data. The outstanding physico-chemical feature of 3874 H3 is its improved solubility. The new heptaenes are potent antifungal compounds with broad activity spectra, encompassing dermatophytes, yeasts and filamentous fungi.