Molecular signatures of angiogenesis inhibitors: a single-embryo untargeted metabolomics approach in zebrafish

Angiogenesis is a key process in embryonic development, a disruption of this process can lead to severe developmental defects, such as limb malformations. The identification of molecular perturbations representative of antiangiogenesis in zebrafish embryo (ZFE) may guide the assessment of developmental toxicity from an endpoint- to a mechanism-based approach, thereby improving the extrapolation of findings to humans. Thus, the aim of the study was to discover molecular changes characteristic of antiangiogenesis and developmental toxicity. We exposed ZFEs to two antiangiogenic drugs (SU4312, sorafenib) and two developmental toxicants (methotrexate, rotenone) with putative antiangiogenic action. Molecular changes were measured by performing untargeted metabolomics in single embryos. The metabolome response was accompanied by the occurrence of morphological alterations. Two distinct metabolic effect patterns were observed. The first pattern comprised common effects of two specific angiogenesis inhibitors and the known teratogen methotrexate, strongly suggesting a shared mode of action of antiangiogenesis and developmental toxicity. The second pattern involved joint effects of methotrexate and rotenone, likely related to disturbances in energy metabolism. The metabolites of the first pattern, such as phosphatidylserines, pterines, retinol, or coenzyme Q precursors, represented potential links to antiangiogenesis and related developmental toxicity. The metabolic effect pattern can contribute to biomarker identification for a mechanism-based toxicological testing

Handling in the Production of Wire-Based Linked Micro Parts

For simplified processing and the enhancement of output rate in multi-stage production, micro parts are handled as linked parts. This contribution discusses handling specific challenges in production based on an exemplary process chain. The examined linked parts consist of spherical elements linked by wire material. Hence, the diameter varies between the wire and part. Nevertheless, the linked parts must be handled accurately. The feed system is an important component too, but special focus is given to the guides in this present study. They must adapt to the diameters of both the parts and the linking wires. Two alternative variants of adaptive guides are presented and investigated under the aspects of precise radial guiding, vibration isolation, damping behavior and friction force

Interactions between feed system and process in production of preforms as linked micro parts

This contribution deals with interactions between feed system and process in the production of preforms as linked parts, which is the first step of a multi-stage process chain for cold forming of micro parts. Due to the interconnection of the parts, the feed system is not only used for part transport, but also for the positioning during the generation of the preforms by laser rod melting. Thereby, the influence of the feed system on the production is more significant. Absorbed laser energy melts a wire, so that a melt pool is formed. While the wire is fixed on one side, the other side is fed into the melt pool whose volume increases. The production can be divided in the steps of preheating, active melting, solidification and transportation. The positioning takes place in parallel to the melting. Until now, the increase of the output rate was based especially on the consideration of the melting process and higher feed velocities. In this contribution, the interactions between feed and process are analyzed with the goal of further increasing the output rate. For that reason, the positioning behavior and its influence on the geometry of the produced preforms are analyzed. Finally, a method is presented, which unites the steps of transportation, preheating and melting. It is shown, that by a favorable coordination of the individual process steps, a further increase of the output rate is achievable without significantly worsening part quality

Increased output in micro production by tolerance field widening and synchronisation

The manufacturing of linked micro parts simplifies the handling and facilitates a consideration of trends due to the maintaining of the manufacturing order. These known changes of geometrical characteristics of parts are the basis for softening tolerances. The basic idea of the tolerance field widening is familiar with selective assembly. Instead of single parts, trend-based sections are used for increasing the number of assemblies under consideration of the clearance. The outcome of the assembly of the identified trend-based sections is influenced by the occurring trends and the changes of trends. Therefore, based on simulated data the effects of occurring trends are investigated. For sorting and matching the identified trend-based sections in high quantities, a case specific pre-assembly in the synchronisation point is required. Possible synchronisation scenarios as well as a synchronisation station for the synchronisation of two types of linked parts are presented. The results for the influence of trends show that the tolerance field widening increases the outcome especially for intersecting and opposing trends

Increased output in micro production by tolerance field widening and synchronisation

The manufacturing of linked micro parts simplifies the handling and facilitates a consideration of trends due to the maintaining of the manufacturing order. These known changes of geometrical characteristics of parts are the basis for softening tolerances. The basic idea of the tolerance field widening is familiar with selective assembly. Instead of single parts, trend-based sections are used for increasing the number of assemblies under consideration of the clearance. The outcome of the assembly of the identified trend-based sections is influenced by the occurring trends and the changes of trends. Therefore, based on simulated data the effects of occurring trends are investigated. For sorting and matching the identified trend-based sections in high quantities, a case specific pre-assembly in the synchronisation point is required. Possible synchronisation scenarios as well as a synchronisation station for the synchronisation of two types of linked parts are presented. The results for the influence of trends show that the tolerance field widening increases the outcome especially for intersecting and opposing trends

Material flow control in plunge micro rotary swaging

In rotary swaging, the material flow is not fully controlled by closure of the forming dies. This is especially noticeable in plunge rotary swaging of rod, where the workpiece is positioned into the forming zone und processed locally. As result, an uncontrolled elongation of the workpiece in axial direction takes place and an axial position shift of the workpiece relative to the dies occurs. This is a special challenge in production of linked micro parts, where single parts are interconnected in order to enable the handling as a strip and thereby a roll-to-roll production. The axial shift influences not only the subsequent positioning of neighbouring parts, but also the final geometry of the currently processed part. The presented investigation analyses the material flow during plunge micro rotary swaging on basis of in-process measurements of the workpiece shift on both sides of the forming zone as well as with the help of contour measurements of the processed parts. It is shown that the measured shift is strongly influenced by the workpiece clamping and fixation and that it can be controlled by applying low axial forces to the workpiece on one or both sides of the forming zone. Further, the geometry of the workpiece can be affected by these measures

Wire Joining by Rotary Swaging

AbstractA new wire joining process for wires with sub-millimeter diameters applying the rotary swaging was investigated. The basic idea is to join two wire ends by a tube segment. In the study different material combinations using steel (AISI304) and copper (CW004A) were examined. Further the realization of a form-locked joint was investigated. The formed samples were tested by optical microscopy and tensile testing and compared to spot welded samples

A Rare Case of Complex Pelvic Injury and Associated Intrathecal Fat Embolism due to Spinopelvic Dislocation with Sacral Burst Fracture

Introduction. Pelvic and lumbar spine injuries are very common especially in multiple trauma patients. The usual mechanism in young patients leading to pelvic fractures is a high-energy trauma such as traffic accidents. In elderly patients, low energy traumas are causal for such injuries. Compared to the high number of patients with pelvic or lumbar spine injuries, cerebral fat embolism is a quite rare finding but it needs to be considered to not misinterpret the radiological findings. Case. We present the case of a 41-year-old patient, who got hit and trapped in the lumbar region by a hydraulic arm in a car repair shop. The patient was primarily admitted to a level II trauma center. The radiological and clinical examinations revealed an open pelvic type C injury in terms of a spinopelvic dissociation, dislocation of the left hip joint, rupture of the mesentery of the rectum and colon sigmoideum, and a complex injury to the left ureter. Additionally, CT scan showed fluid with higher density than cerebro spinal fluid (CSF) in the lateral ventricles indicating an intracranial bleeding. After an immediate surgery to stabilize the patient, he was admitted to a level I trauma center. The reanalysis of the existing CT datasets combined with a new head CT leads to the conclusion that the high density fluid in the lateral ventricles is not a intracranial bleeding but rather fat deriving from the complex pelvic and lumbar spine fracture into the CSF system. Therefore, an immediate operation was performed to stabilize the spinopelvic dissociation and to close the injured dural sheath. Additionally, a ventricle drainage has been placed, which confirmed the diagnosis of intrathecal fat embolism. Afterwards, complex plastic surgery was necessary to restore the soft tissue damage. Conclusions. Intrathecal fat embolism in muliple trauma patients is a rare condition, which should be considered in patients with complex spine or pelvic injuries. It is important to distinguish this rare condition from intracranial bleedings, which are much more common because the consequent therapeutic strategy is quite different. In case of intrathecal fat embolism, a ventricle drainage system should be placed immediately, and the underlying spine or pelvic injuries need to be stabilized combined with closure of the dural sheath to prevent continuous fat embolism and meningeal infection

Planar cell polarity breaks bilateral symmetry by controlling ciliary positioning

Defining the three body axes is a central event of vertebrate morphogenesis. Establishment of left-right (L-R) asymmetry in development follows the determination of dorsal-ventral and anterior-posterior (A-P) body axes, although the molecular mechanism underlying precise L-R symmetry breaking in reference to the other two axes is still poorly understood. Here, by removing both Vangl1 and Vangl2, the two mouse homologues of a Drosophila core planar cell polarity (PCP) gene Van Gogh (Vang), we reveal a previously unrecognized function of PCP in the initial breaking of lateral symmetry. The leftward nodal flow across the posterior notochord (PNC) has been identified as the earliest event in the de novo formation of L-R asymmetry. We show that PCP is essential in interpreting the A-P patterning information and linking it to L-R asymmetry. In the absence of Vangl1 and Vangl2, cilia are positioned randomly around the centre of the PNC cells and nodal flow is turbulent, which results in disrupted L-R asymmetry. PCP in mouse, unlike what has been implicated in other vertebrate species, is not required for ciliogenesis, cilium motility, Sonic hedgehog (Shh) signalling or apical docking of basal bodies in ciliated tracheal epithelial cells. Our data suggest that PCP acts earlier than the unidirectional nodal flow during bilateral symmetry breaking in vertebrates and provide insight into the functional mechanism of PCP in organizing the vertebrate tissues in development