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Fragestellung: Die Arthrose des Kniegelenkes (OA) stellt aufgrund unserer zunehmend alternden Gesellschaft eine wachsende sozioökonomische Belastung dar. Wachstumsfaktor-basierte regenerative Therapieansätze könnten eine zukünftige Behandlungsoption darstellen dem Knorpelverlust,[zum vollständigen Text gelangen Sie über die oben angegebene URL], Deutscher Kongress für Orthopädie und Unfallchirurgie (DKOU 2016)

Fragestellung: Unzureichende Regeneration peripherer Nerven stellt im klinischen Alltag nach wie vor ein ernsthaftes Problem dar. Daher ist es notwendig neue Therapieansätze zu entwickeln. Als Goldstandard zur Überbrückung größerer Kontinuitätslücken gilt in der klinischen[zum vollständigen Text gelangen Sie über die oben angegebene URL], 47. Jahrestagung der Deutschen Gesellschaft der Plastischen, Rekonstruktiven und Ästhetischen Chirurgen (DGPRÄC), 21. Jahrestagung der Vereinigung der Deutschen Ästhetisch-Plastischen Chirurgen (VDÄPC)

Einleitung: Das Potenzial von multipotenten Stamm-/Vorläuferzellen aus Fettgewebe (ASPCs) für die regenerative Medizin ist gut belegt. Problematisch für den klinischen Einsatz von ASPCs ist jedoch die Zellisolation, welche oft Expansionsschritte außerhalb des OPs beinhaltet.[zum vollständigen Text gelangen Sie über die oben angegebene URL], 47. Jahrestagung der Deutschen Gesellschaft der Plastischen, Rekonstruktiven und Ästhetischen Chirurgen (DGPRÄC), 21. Jahrestagung der Vereinigung der Deutschen Ästhetisch-Plastischen Chirurgen (VDÄPC)

The loss and degradation of articular cartilage tissue matrix play central roles in the process of osteoarthritis (OA). New models for evaluating cartilage repair/regeneration are thus of great value for transferring various culture systems into clinically relevant situations. The repair process can be better monitored in ex vivo systems than in in vitro cell cultures. I have therefore established an ex vivo defect model prepared from bovine femoral condyles for evaluating cartilage repair by the implantation of cells cultured in various ways, e.g., monolayer-cultured cells or suspension or pellet cultures of articular bovine chondrocytes representing different cell compactions with variable densities of chondrocytes. I report that the integrin subunit α10 was significantly upregulated in suspension-cultured bovine chondrocytes at passage P2 compared with monolayer-cultured cells at P1 (p = 0.0083) and P2 (p

Recent studies underscored the clinical potential of adipose-derived multipotent stem-/precursor cells (ASPCs). One of the main hurdles en route to clinical application was to isolate cells without having to perform expansion cultures outside the OR. A new generation of clinically approved, commercially available cell separation systems claims to provide ASPCs ready for application without further expansion cultures. However, it is unclear if the new systems yield sufficient cells of adequate quality for the use in autologous murine models. The aim of this study was to isolate and characterize adipose-derived precursor cells taken from the inguinal fat pat of wistar rats using InGeneron's clinically approved ARC™-cell separation system.We isolated cells from the inguinal fat pad of 3 male Wistar rats according to the manufacturer's protocol. In order to reduce the influence of the atmospheric oxygen on the multipotent precursor cells, one half of the cell suspension was cultivated under hypoxia (2% O2) simulating physiological conditions for ASPCs. As a control, the other half of the cells were cultivated under normoxia (21% O2). Cell surface markers CD90, CD29, CD45 and CD11b/c were analyzed by FACS, and osteogenic and adipogenic differentiation of the ASPCs was performed. Finally, cellular growth characteristics were assessed by evaluation of the cumulative population doublings and CFU assay, and metabolic activity was evaluated by WST-1 assay.Processing time was 90 (± 12) min. 1 g of adipose tissue yielded approximately 60 000 plastic adhering cells. Both groups showed a high expression of the mesenchymal stem cell markers CD90 and CD29 while they were negative for the leucocyte markers CD45 and CD11b/c. A strong osteogenic differentiation and a sufficient adipogenic differentiation potential was proven for all ASPCs. Under hypoxia, ASPCs showed increased proliferation characteristics and CFU efficiency as well as a significantly increased metabolic activity.This study showed that sufficient multipotent ASPCs of appropriate quality can be isolated from the inguinal fat pad of Wistar rats using the ARC™-cell separation system. As shown in previous studies, cultivation of cells under hypoxic conditions increased their stemness. Our findings will enable future studies that focus on autologous transplantation of ASPCs in a rat model, which most closely resembles a possible clinical application.

Zielsetzung: Metaphysäre Frakturen stellen insbesondere in osteoporotischem Knochen eine chirurgische Herausforderung dar. Um eine zügige Mobilisation der überwiegend geriatrischen Patienten zu gewährleisten, sind an eine Osteosynthese hohe Anforderungen zu stellen. Für eine[zum vollständigen Text gelangen Sie über die oben angegebene URL], Alterstraumatologie Kongress 2016

An efficient method for the synthesis of new macromolecular surface ligands for quantum dots functionalization has been developed. The new ligands contain a dihydrolipoic acid unit which is connected to either a mono- or a diacid terminal function by a PEG chain.

ObjectiveInterterritorial regions of articular cartilage matrix are rich in decorin, a small leucine-rich proteoglycan and important structural protein, also involved in many signalling events. Decorin sequesters transforming growth factor β (TGFβ), thereby regulating its activity. Here, we analysed whether increased bioavailability of TGFβ in decorin-deficient (Dcn−/−) cartilage leads to changes in biomechanical properties and resistance to osteoarthritis (OA).MethodsUnchallenged knee cartilage was analysed by atomic force microscopy (AFM) and immunohistochemistry. Active transforming growth factor β-1 (TGFβ1) content within cultured chondrocyte supernatants was measured by ELISA. Quantitative real-time (RT)-PCR was used to analyse mRNA expression of glycosaminoglycan (GAG)-modifying enzymes in C28/I2 cells following TGFβ1 treatment. In addition, OA was induced inDcn−/−and wild-type (WT) mice via forced exercise on a treadmill.ResultsAFM analysis revealed a strikingly higher compressive stiffness inDcn−/−than in WT cartilage. This was accompanied by increased negative charge and enhanced sulfation of GAG chains, but not by alterations in the levels of collagens or proteoglycan core proteins. In addition, decorin-deficient chondrocytes were shown to release more active TGFβ1. Increased TGFβ signalling led to enhancedChst11sulfotransferase expression inducing an increased negative charge density of cartilage matrix. These negative charges might attract more water resulting in augmented compressive stiffness of the tissue. Therefore, decorin-deficient mice developed significantly less OA after forced exercise than WT mice.ConclusionsOur study demonstrates that the disruption of decorin-restricted TGFβ signalling leads to higher stiffness of articular cartilage matrix, rendering joints more resistant to OA. Therefore, the loss of an important structural component can improve cartilage homeostasis.

During homeostasis, hematopoietic stem cells (HSCs) are mostly kept in quiescence with only minor contribution to steadystate hematopoiesis. However, in stress situations such as infection, chemotherapy, or transplantation, HSCs are forced to proliferate and rapidly regenerate compromised hematopoietic cells. Little is known about the processes regulating this stress-induced proliferation and expansion of HSCs and progenitors. In this study, we identified the extracellular matrix (ECM) adaptor protein Matrilin-4 (Matn4) as an important negative regulator of the HSC stress response. Matn4 is highly expressed in long-term HSCs; however, it is not required for HSC maintenance under homeostasis. In contrast, Matn4 is strongly down-regulated in HSCs in response to proliferative stress, and Matn4 deficiency results in increased proliferation and expansion of HSCs and progenitors after myelosuppressive chemotherapy, inflammatory stress, and transplantation. This enhanced proliferation is mediated by a transient down-regulation of CXCR4 in Matn4(-/-) HSCs upon stress, allowing for a more efficient expansion of HSCs. Thus, we have uncovered a novel link between the ECM protein Matn4 and cytokine receptor CXCR4 involved in the regulation of HSC proliferation and expansion under acute stress.

The voice and vocalizing subjects have long been a discussed in philosophical, cultural and critical studies circles as places in which meaning lives and is conveyed. In recent years, through developments in musicology, artistic research and autoethnography the bodies of performers have taken on renewed significance for knowledge production. The subjectivities involved in the realization of musical works are now being unpacked and traditional notions of objectivity and concrete meaning as conveyed by musical texts, have eroded. Voicing Subjectivity argues for vocal subjectivity as a site for exploration and experiment in practice-based, artistic research. It queries whether a conscious negotiation of performer subjectivity makes for stronger practice and realizations in new vocal music? The thesis presents two projects, realizing five new and recent notated works for voice. The researcher performs and problematizes her multiple realizations of Helmut Lachenmann’s Got Lost (2008), Jeanette Little’s Mechanical Bride (2013), Alexander Garsden’s [ja] Maser (2014), James Rushford’s The fabric of Wind (2014) and Anthony Pateras’ Prayer for Nil (2014). Informed by and situated within literature from subjectivity studies, interdisciplinary voice studies, music-history and professional vocal practice the author describes her artistic research through three stages: preparation, performance and recording. The exegesis fleshes out issues of embodiment, the indiscrete subject, technologized voice and inter-subjectivity through an active performer’s practice in a mixed-methodological framework that integrates elements from artistic research and auto-ethnography. By applying a considered methodological structure and actively focusing the lens through which problem-solving takes place, the author demonstrates how the conscious negotiation of subjectivity enables better understanding of practice and makes the site of knowledge production, the living subject of the author, a site that is fit to purpose.

Correct innervation of the main respiratory muscle in mammals, namely the thoracic diaphragm, is a crucial pre-requisite for the functionality of this muscle and the viability of the entire organism. Systemic impairment of Sema3A–Npn-1 (Npn-1 is also known as NRP1) signaling causes excessive branching of phrenic nerves in the diaphragm and into the central tendon region, where the majority of misguided axons innervate ectopic musculature. To elucidate whether these ectopic muscles are a result of misguidance of myoblast precursors due to the loss of Sema3A–Npn-1 signaling, we conditionally ablated Npn-1 in somatic motor neurons, which led to a similar phenotype of phrenic nerve defasciculation and, intriguingly, also formation of innervated ectopic muscles. We therefore hypothesize that ectopic myocyte fusion is caused by additional factors released by misprojecting growth cones. Slit2 and its Robo receptors are expressed by phrenic motor axons and migrating myoblasts, respectively, during innervation of the diaphragm. In vitro analyses revealed a chemoattractant effect of Slit2 on primary diaphragm myoblasts. Thus, we postulate that factors released by motor neuron growth cones have an influence on the migration properties of myoblasts during establishment of the diaphragm., Highlighted Article: Sema3A–Npn-1 signaling cell autonomously influences phrenic nerve branching in the diaphragm and induces ectopic muscle formation through secondary mechanisms, possibly by Slit–Robo signaling.

Fragestellung: Infolge der demographischen Entwicklung wird die Inzidenz osteoporoseassoziierter Frakturen in den nächsten Jahren ansteigen. Die proximale Femurfraktur ist eine der häufigsten und prognostisch schwerwiegendsten Manifestationen der Osteoporose. Patienten mit einer osteoporotischen[zum vollständigen Text gelangen Sie über die oben angegebene URL], Deutscher Kongress für Orthopädie und Unfallchirurgie (DKOU 2015)

Collagen IX (Col IX) is an important component of the cartilage extracellularmatrix and has been associated with degenerative cartilage disorders and chondrodysplasias in humans. Further, polymorphisms in Col IX are known risk factors for the development of early intervertebral disc (IVD) degeneration. To understand the role of Col IX in the pathogenesis of IVD disorders, the spine of newborn and older Col IX deficient mice was systematically analyzed and compared to C57BL/6N controls. Morphology and bone parameters of the spine from newborn, 6 and 10 months old animals were investigated using μCT measurements. Histological staining was used to evaluate tissue structure and degree of degeneration. Localization and expression of extracellularmatrix proteins was analyzed in depth by immunofluorescence staining, immunoblotting, RT-PCR and in situ hybridization. High resolution imaging and stiffness measurements were performed by atomic force microscopy (AFM). Vertebral bodies of newborn Col IX-deficient mice were smaller and showed an increased mineral density compared to wild type animals. At birth, lack of Col IX led to a disrupted cellular organization in the cartilaginous endplate and a smaller nucleus pulposus of the IVD.Expression levels and localization of other extracellularmatrix proteins were strongly altered accompanied by a softening of cartilaginous tissues. In older animals, absence of Col IX caused earlier and more pronounced disc degeneration with annular fissures. The absence of Col IX induces early developmental, structural and biomechanical alterations in both vertebral body and intervertebral disc which eventually cause severe degenerative changes in the aging spine.

A novel kind of miniaturized, all optical probe concept to measure the elasticity of biological tissues is here presented. The probe is based on fibre Bragg grating sensors (FBG) inscribed in optical fibres. The measurement procedure exploits the high strain sensitivity of Bragg gratings. A study on the reproducibility, reliability, and resolution of the sensor is presented and a first measurement on bovine cartilage tissue is reported. A linear elastic model of the cartilage has been used to analyse the data. The results indicate a good agreement with previous values given in the literature for micro-indentation.

Collagen prolyl 4-hydroxylases (C-P4H-I, C-P4H-II, and C-P4H-III) catalyze formation of 4-hydroxyproline residues required to form triple-helical collagen molecules. Vertebrate C-P4Hs are α2β2 tetramers differing in their catalytic α subunits. C-P4H-I is the major isoenzyme in most cells, and inactivation of its catalytic subunit (P4ha1(-/-)) leads to embryonic lethality in mouse, whereas P4ha1(+/-) mice have no abnormalities. To study the role of C-P4H-II, which predominates in chondrocytes, we generated P4ha2(-/-) mice. Surprisingly, they had no apparent phenotypic abnormalities. To assess possible functional complementarity, we established P4ha1(+/-);P4ha2(-/-) mice. They were smaller than their littermates, had moderate chondrodysplasia, and developed kyphosis. A transient inner cell death phenotype was detected in their developing growth plates. The columnar arrangement of proliferative chondrocytes was impaired, the amount of 4-hydroxyproline and the Tm of collagen II were reduced, and the extracellular matrix was softer in the growth plates of newborn P4ha1(+/-);P4ha2(-/-) mice. No signs of uncompensated ER stress were detected in the mutant growth plate chondrocytes. Some of these defects were also found in P4ha2(-/-) mice, although in a much milder form. Our data show that C-P4H-I can to a large extent compensate for the lack of C-P4H-II in proper endochondral bone development, but their combined partial and complete inactivation, respectively, leads to biomechanically impaired extracellular matrix, moderate chondrodysplasia, and kyphosis. Our mouse data suggest that inactivating mutations in human P4HA2 are not likely to lead to skeletal disorders, and a simultaneous decrease in P4HA1 function would most probably be required to generate such a disease phenotype.

Anti-Bredt bridged bicyclo[3.2.1] gamma-lactams were designed as inhibitors of penicillin binding proteins (PBPs). The compounds were prepared by a carbenoid insertion into a lactam N-H bond. Their weak antibacterial activity could either be explained by a poor chemical stability or by unfavorable steric interactions of the methylene bridge of the gamma-lactam with the targeted enzymes.

A new diol-carbonyl transposition reaction has been discovered in echinocandin type structures. An α-hydroxy hemiaminal moiety has been shown to undergo a pinacol-type rearrangement in the presence of trimethylsilyl iodide to afford ketone derivatives. Applied to deoxymulundocandin, this transposition led to a useful intermediate for further chemical modification.

Long-bone growth by endochondral ossification is cooperatively accomplished by chondrocyte proliferation, hypertrophic differentiation, and appropriate secretion of collagens, glycoproteins, and proteoglycans into the extracellular matrix (ECM). Before folding and entering the secretory pathway, ECM macromolecules in general are subject to extensive posttranslational modification, orchestrated by chaperone complexes in the endoplasmic reticulum (ER). ERp57 is a member of the protein disulfide isomerase (PDI) family and facilitates correct folding of newly synthesized glycoproteins by rearrangement of native disulfide bonds. Here, we show that ERp57-dependent PDI activity is essential for postnatal skeletal growth, especially during the pubertal growth spurt characterized by intensive matrix deposition. Loss of ERp57 in growth plates of cartilage-specific ERp57 knockout mice (ERp57 KO) results in ER stress, unfolded protein response (UPR), reduced proliferation, and accelerated apoptotic cell death of chondrocytes. Together this results in a delay of long-bone growth with the following characteristics: (1) enlarged growth plates; (2) expanded hypertrophic zones; (3) retarded osteoclast recruitment; (4) delayed remodeling of the proteoglycan-rich matrix; and (5) reduced numbers of bone trabeculae. All the growth plate and bone abnormalities, however, become attenuated after the pubertal growth spurt, when protein synthesis is decelerated and, hence, ERp57 function is less essential.

Due to the importance of the cephems, it is essential to classify them so as to allow their optimal use. The cephems are characterized by an azetidinone ring, to which is attached an unsaturated hexacycle. Five classes of cephems may be distinguished in terms of the nature of the moiety: cephalosporins, cephamycins and cephabacins, oxa-1-cephems, carba-1-cephems, and miscellaneous. The dosage and dosing frequency of a cephalosporin are the result of a balance between its antibacterial activity and its pharmacokinetic profile. The molecules all have the same antibacterial spectrum, which principally includes gram-negative bacilli and gram-negative and gram-positive cocci, except for S. aureus. The carbacephem-type molecules are asymmetrical, and the substituents on the β-lactam moiety are in the cis position; the cis stereochemistry of the carbacephems is less stable thermodynamically than the trans stereochemistry. The antibacterial activity RWJ-54428 was designed to overcome methicillin resistance in methicillin-resistant S. aureus (MRSA) strains and ampicillin resistance in E. faecium by penicillin-binding proteins (PBP) alterations. In all species, total clearance was slower and the apparent elimination half-life was longer than that of RWJ- 54428. The antistaphylococcal activities of RWJ-333442 in comparison with RWJ-54428, vancomycin, and quinupristindalfopristin against S. aureus Smith were investigated in a sepsis model (Swiss-Webster mice) and were also investigated for S. aureus 076, a methicillin-resistant strain. A synergistic activity was shown to be species dependent in combination with streptomycin against E. faecalis.

A new strategy using a colored dendrimer as visible soluble support for organic synthesis has been developed. The efficiency of this new system has been demonstrated by the use of DRHMPA9–CH2OH as the support in a Suzuki coupling reaction. Due to the visibility of the support, following of the reaction has been rendered easier and the purification time of the crude product has been considerably shortened.

Tunicamycins (TCMs) and liposidomycins (LPMs) are naturally occurring inhibitors of the bacterial translocase (MraY). Based on structure-activity relationship (SAR) studies, a molecular model has been proposed for their inhibitory mechanism. This study points out the importance of the nucleoside moiety of liposidomycins in the inhibition of MraY. A simplified molecule (I) based on the liposidomycin core structure has been synthesised and tested on MraY. The compound displayed a moderate inhibitory activity (IC50 = 50 microM). The validation of the molecular model was then performed by synthesising higher homologues of I, containing an additional stereocentre in the 5' position (XIV and XV). In agreement with the prediction, only the (S) isomer XV showed significant activity against MraY (IC50 = 5 microM).

A vinylogous cephalosporine bearing a dihydroxythiophene moiety as a potential catechol surrogate has been synthesised ( I-e Download : Download high-res image (58KB) Download : Download full-size image Figure 1 . -β). Even if the anti staphylococcus spectrum displayed by this compound is of interest, its activity against Pseudomonas species, expected for such a structure, remains disappointing.

The penicillin-binding protein (PBP) 1b of Escherichia coli catalyses the assembly of lipid-transported N-acetyl glucosaminyl-beta-1, 4-N-acetylmuramoyl-L-alanyl-gamma-D-glutamyl-(L)-meso-diaminopimelyl+ ++- (L)-D-alanyl-D-alanine disaccharide pentapeptide units into polymeric peptidoglycan. These units are phosphodiester linked, at C1 of muramic acid, to a C55 undecaprenyl carrier. PBP1b has been purified in the form of His tag (M46-N844) PBP1bgamma. This derivative provides the host cell in which it is produced with a functional wall peptidoglycan. His tag (M46-N844) PBP1bgamma possesses an amino-terminal hydrophobic segment, which serves as transmembrane spanner of the native PBP. This segment is linked, via an congruent with 100-amino-acid insert, to a D198-G435 glycosyl transferase module that possesses the five motifs characteristic of the PBPs of class A. In in vitro assays, the glycosyl transferase of the PBP catalyses the synthesis of linear glycan chains from the lipid carrier with an efficiency of congruent with 39 000 M-1 s-1. Glu-233, of motif 1, is central to the catalysed reaction. It is proposed that the Glu-233 gamma-COOH donates its proton to the oxygen atom of the scissile phosphoester bond of the lipid carrier, leading to the formation of an oxocarbonium cation, which then undergoes attack by the 4-OH group of a nucleophile N-acetylglucosamine. Asp-234 of motif 1 or Glu-290 of motif 3 could be involved in the stabilization of the oxocarbonium cation and the activation of the 4-OH group of the N-acetylglucosamine. In turn, Tyr-310 of motif 4 is an important component of the amino acid sequence-folding information. The glycosyl transferase module of PBP1b, the lysozymes and the lytic transglycosylase Slt70 have much the same catalytic machinery. They might be members of the same superfamily. The glycosyl transferase module is linked, via a short junction site, to the amino end of a Q447-N844 acyl transferase module, which possesses the catalytic centre-defining motifs of the penicilloyl serine transferases superfamily. In in vitro assays with the lipid precursor and in the presence of penicillin at concentrations sufficient to derivatize the active-site serine 510 of the acyl transferase, the rate of glycan chain synthesis is unmodified, showing that the functioning of the glycosyl transferase is acyl transferase independent. In the absence of penicillin, the products of the Ser-510-assisted double-proton shuttle are glycan strands substituted by cross-linked tetrapeptide-pentapeptide and tetrapeptide-tetrapeptide dimers and uncross-linked pentapeptide and tetrapeptide monomers. The acyl transferase of the PBP also catalyses aminolysis and hydrolysis of properly structured thiolesters, but it lacks activity on D-alanyl-D-alanine-terminated peptides. This substrate specificity suggests that carbonyl donor activity requires the attachment of the pentapeptides to the glycan chains made by the glycosyl transferase, and it implies that one and the same PBP molecule catalyses transglycosylation and peptide cross-linking in a sequential manner. Attempts to produce truncated forms of the PBP lead to the conclusion that the multimodular polypeptide chain behaves as an integrated folding entity during PBP1b biogenesis.