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Background: Myxoid liposarcomas (MLS) can exhibit a disseminated metastatic pattern, necessitating extensive diagnostics during follow-up. With no tumor markers available, early diagnosis of recurrences and tumor monitoring is difficult. The detection of circulating tumor DNA (ctDNA; liquid biopsy) in MLS with the characteristic translocations t(12;16) and t(12;22) can provide an additional diagnostic. However, due to the often very low tumor fraction, distinguishing actual tumor variants from sequencing artifacts remains a key challenge., Methods: Using MLS as a model for translocation-driven tumors, this study evaluates a refined analytical approach for detecting both single nucleotide variants (SNVs) and structural variants (SVs) with the highest possible sensitivity and specificity. Different analysis pipelines using Unique Molecular Identifiers (UMIs) were compared in dilution series of tumor DNA from MLS patients (n = 11) and a cell line. The results were validated on plasma samples (n = 36) from two MLS patients and one patient with Synovial Sarcoma (SS)., Results: In dilution series, the use of UMIs significantly reduced false positive events in SNV analysis while maintaining high sensitivity without significant differences. In SV analysis, the effect of UMIs was not consistently detectable, as some dilution series exhibited no false positive events even without UMI correction. Additional filter criteria further improved specificity without significantly compromising assay sensitivity. Validation on patient plasma samples confirmed these findings, demonstrating the advantages of the differentiated analytical approach., Conclusion: By integrating a refined analytical approach for SNVs and SVs, we achieved reliable ctDNA detection that corresponded with the clinical course of the patients' disease. This method enables non-invasive tumor detection in translocation-driven tumors with low mutational burden and can easily be adapted into routine clinical diagnostics., (© 2025 The Author(s). Cancer Medicine published by John Wiley & Sons Ltd.)

Background: C-reactive protein (CRP) represents a routine diagnostic marker of inflammation. Dissociation of native pentameric CRP (pCRP) into the monomeric structure (mCRP) liberates proinflammatory features, presumably contributing to excessive immune cell activation via unknown molecular mechanisms., Results: In a multi-translational study of systemic inflammation, we found a time- and inflammation-dependent pCRP dissociation into mCRP. We were able to confirm that mCRP co-localizes with leukocytes at the site of injury after polytrauma and therefore assessed whether the CRP conformation potentiates neutrophil activation. We found mCRP-induced neutrophil-extracellular trap formation in vitro and ex vivo involving nicotinamide adenine dinucleotide phosphate oxidase activation, p38/mitogen-activated protein kinase signaling, and histone H3 citrullination. Mimicking the trauma milieu in a human ex vivo whole blood model, we found significant mCRP generation as well as NET formation, prevented by blocking pCRP conformational changes., Conclusions: Our data provide novel molecular insights how CRP dissociation contributes to neutrophil activation as driver of various inflammatory disorders., Competing Interests: Declarations. Ethics approval and consent to participate: A prospective clinical study was conducted in patients after severe PT (Injury Severity Score ≥ 32) that were admitted to the University Hospital Ulm between December 2013 and May 2015. The study protocol was approved by the Independent Local Ethics Committee of the University of Ulm (approval numbers 244/11 and 94/14). The study was registered on ClinicalTrials.gov, identifiers NCT00710411 and NCT02682550, and was performed in accordance with the Declaration of Helsinki and its recent modifications. Consent for publication: Not applicable. Competing interests: The authors have declared that no conflict of interest exists., (© 2025. The Author(s).)

Background/Objectives: The perioperative interplay between blood pressure, vasopressors, and macrocirculation is well established. However, in the context of free flap surgery, the potential impact of these factors on microvascular flow remains elusive. The aim was to evaluate the impact of norepinephrine administration on the microcirculation of free flaps. Methods: Postoperative systolic blood pressure (sBP), norepinephrine infusion rates (NIRs), and free flap microcirculation were monitored prospectively and analyzed retrospectively in patients receiving free flap surgery who required postoperative intermediate (IMC) or intensive care (ICU). Blood flow, hemoglobin oxygenation (SO 2 ), and relative hemoglobin levels (rHbs) were measured over a period of 24 hours post-anastomosis by laser-doppler flowmetry and white light spectroscopy using the "Oxygen to See" device (O2C, LEA Medizintechnik, Gießen, Germany). Multivariate analysis was performed to determine the impact of NIR on microvascular flow, adjusting for several confounding factors. Subgroup analysis was conducted by categorizing into three groups based on patients' postoperative sBP. Results: Flaps were performed in 105 patients with a mean age of 61.46 ± 16.29 years. Postoperatively, an increase in microvascular flow over time was observed across all free flaps, while NIR decreased and sBP maintained stable values. Multivariate analysis revealed that the time post-anastomosis (B = 3.76, p < 0.001), SO 2 (B = 0.55, p < 0.001), rHb (B= -0.79, p < 0.001), female gender (B = 29.25, p = 0.02), and no previous radiation therapy (B = 41.21, p = 0.04) had a significant impact on postoperative microvascular flow in free flaps. NIR, sBP, smoking status, old age, and ASA score showed no significant impact on free flap flow. Further, NIR showed no significant impact on microvascular flow in any of the subgroups investigated. Conclusions: These findings support the safety of using norepinephrine for maintaining stable blood pressure without compromising microvascular flow, offering valuable guidance for postoperative management., Competing Interests: The authors declare no conflict of interest.

Introduction: Despite advancements in transplant immunology and vascularized composite allotransplantation (VCA), the longevity of allografts remains hindered by the challenge of allograft rejection. The acute-phase response, an immune-inflammatory reaction to ischemia/reperfusion that occurs directly after allogeneic transplantation, serves as a catalyst for graft rejection. This immune response is orchestrated by acute-phase reactants through intricate crosstalk with the mononuclear phagocyte system., Objective: C-reactive protein (CRP), a well-known marker of inflammation, possesses pro-inflammatory properties and exacerbates ischemia/reperfusion injury. Thus, we investigated how CRP impacts acute allograft rejection., Methods: Prompted by clinical observations in facial VCAs, we employed a complex hindlimb transplantation model in rats to investigate the direct impact of CRP on transplant rejection., Results: Our findings demonstrate that CRP expedites allograft rejection and diminishes allograft survival by selectively activating non-classical monocytes. Therapeutic stabilization of CRP abrogates this activating effect on monocytes, thereby attenuating acute allograft rejection. Intravital imagining of graft-infiltrating, recipient-derived monocytes during the early phase of acute rejection corroborated their differential regulation by CRP and their pivotal role in driving the initial stages of graft rejection., Conclusion: The differential activation of recipient-derived monocytes by CRP exacerbates the innate immune response and accelerates clinical allograft rejection. Thus, therapeutic targeting of CRP represents a novel and promising strategy for preventing acute allograft rejection and potentially mitigating chronic allograft rejection., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Production and hosting by Elsevier B.V.)

Background: Wide resection remains the cornerstone of localized soft-tissue sarcomas (STS) treatment. Neoadjuvant radiation therapy (NRT) may decrease the risk of local recurrences; however, its effectiveness for different histological STS subtypes has not been systematically investigated. The proposed prospective study evaluates the NRT response in STS using liquid biopsies and the correlation of multiparametric magnetic resonance imaging (mpMRI) with histopathology and immunohistochemistry., Methods: Patients with localized high-grade STS, who qualify for NRT, are included in this study., Liquid Biopsies: Quantification of circulating tumor DNA (ctDNA) in patient blood samples is performed by targeted next-generation sequencing. Soft-tissue sarcoma subtype-specific panel sequencing in combination with patient-specific exome sequencing allows the detection of individual structural variants and point mutations. Circulating free DNA is isolated from peritherapeutically collected patient plasma samples and ctDNA quantified therein. Identification of breakpoints is carried out using FACTERA. Bioinformatic analysis is performed using samtools, picard, fgbio, and the MIRACUM Pipeline., Mpmri: Combination of conventional MRI sequences with diffusion-weighted imaging, intravoxel-incoherent motion, and dynamic contrast enhancement. Multiparametric MRI is performed before, during, and after NRT. We aim to correlate mpMRI data with the resected specimen's macroscopical, histological, and immunohistochemical findings., Results: Preliminary data support the notion that quantification of ctDNA in combination with tumor mass characterization through co-registration of mpMRI and histopathology can predict NRT response of STS., Clinical Relevance: The methods presented in this prospective study are necessary to assess therapy response in heterogeneous tumors and lay the foundation of future patient- and tumor-specific therapy concepts. These methods can be applied to various tumor entities. Thus, the participation and support of a wider group of oncologic surgeons are needed to validate these findings on a larger patient cohort., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 Runkel et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

C-reactive protein (CRP) is an early-stage acute phase protein and highly upregulated in response to inflammatory reactions. We recently identified a novel mechanism that leads to a conformational change from the native, functionally relatively inert, pentameric CRP (pCRP) structure to a pentameric CRP intermediate (pCRP*) and ultimately to the monomeric CRP (mCRP) form, both exhibiting highly pro-inflammatory effects. This transition in the inflammatory profile of CRP is mediated by binding of pCRP to activated/damaged cell membranes via exposed phosphocholine lipid head groups. We designed a tool compound as a low molecular weight CRP inhibitor using the structure of phosphocholine as a template. X-ray crystallography revealed specific binding to the phosphocholine binding pockets of pCRP. We provide in vitro and in vivo proof-of-concept data demonstrating that the low molecular weight tool compound inhibits CRP-driven exacerbation of local inflammatory responses, while potentially preserving pathogen-defense functions of CRP. The inhibition of the conformational change generating pro-inflammatory CRP isoforms via phosphocholine-mimicking compounds represents a promising, potentially broadly applicable anti-inflammatory therapy., (© 2022 The Authors. Published under the terms of the CC BY 4.0 license.)

A central element of modern sarcoma therapy is complete surgical tumor resection with an adequate safety margin, embedded in an interdisciplinary multimodal therapy concept. Along with ensuring patient survival, functional limb preservation is an important goal for sarcomas of the extremities. This review provides an overview of the relevant literature on indications and goals of reconstructive options, the scope and contribution of microsurgical reconstructive procedures, and the associated interdisciplinary decision making and workup. Furthermore, the impact of (neo)-adjuvant therapy on reconstructive decisions will be highlighted. These aspects will be illustrated by four comprehensive case studies that demonstrate both useful strategies and the need for individually tailored therapies. Nowadays, extremity-preserving therapy is possible in more than 90% of sarcomas. Technical and procedural innovations such as microsurgery and microsurgical reconstructive procedures have significantly contributed to this evolution of therapy.

Soft tissue sarcomas (STS) are rare tumors of mesenchymal origin with high mortality. After curative resection, about one third of patients suffer from distant metastases. Tumor follow-up only covers a portion of recurrences and is associated with high cost and radiation burden. For metastasized STS, only limited inferences can be drawn from imaging data regarding therapy response. To date there are no established and evidence-based diagnostic biomarkers for STS due to their rarity and diversity. In a proof-of-concept study, circulating tumor DNA (ctDNA) was quantified in ( n = 25) plasma samples obtained from ( n = 3) patients with complex karyotype STS collected over three years. Genotyping of tumor tissue was performed by exome sequencing. Patient-individual mini-panels for targeted next-generation sequencing were designed encompassing up to 30 mutated regions of interest. Circulating free DNA (cfDNA) was purified from plasma and ctDNA quantified therein. ctDNA values were correlated with clinical parameters. ctDNA concentrations correlated with the tumor burden. In case of full remission, no ctDNA was detectable. Patients with a recurrence at a later stage showed low levels of ctDNA during clinical remission, indicating minimal residual disease. In active disease (primary tumor or metastatic disease), ctDNA was highly elevated. We observed direct response to treatment, with a ctDNA decline after tumor resections, radiotherapy, and chemotherapy. Quantification of ctDNA allows for the early detection of recurrence or metastases and can be used to monitor treatment response in STS. Therapeutic decisions can be made earlier, such as the continuation of a targeted adjuvant therapy or the implementation of extended imaging to detect recurrences. In metastatic disease, therapy can be adjusted promptly in case of no response. These advantages may lead to a survival benefit for patients in the future.

Atypical fibroxanthoma (AFX) and pleomorphic dermal sarcoma (PDS) are two distinct designations for a rare dermal sarcoma entity. These tumors arise predominantly in the sun-damaged skin of elderly patients. Although both AFX and PDS have a similar clinical presentation and nearly identical genetic features, they significantly differ in prognosis. Here we present a retrospective single-center chart review analyzing the outcomes of patients treated for dermal sarcoma. The radicality of the tumor-resection extent and soft-tissue reconstructive options were assessed. Patients between January 2010 and August 2021 were included. We recorded resection margins, tumor recurrence, overall survival, number of operations until complete tumor resection, and reconstructive procedures; any complications were recorded. Furthermore, we analyzed a subgroup of patients with satellite metastases. A total of 32 patients met the inclusion criteria (30 male, 2 female, median age of 77.5 years (interquartile range (IQR) 74-81)). Histopathology revealed AFX in 14 patients and PDS in 18 patients. Margin-free resection was achieved in 31 cases, and 27 patients were remission free over the reported period. The local recurrence rate was 5, and distant metastasis was detected in four cases. Of all the PDS cases, nine presented with satellite metastasis. No AFX had satellite metastases. Due to their rarity, managing these tumors requires an interdisciplinary setting in a specialized sarcoma center.

Background: Synovial sarcoma (SS) is a malignant soft tissue tumor of mesenchymal origin that frequently occurs in young adults. Translocation of the SYT gene on chromosome 18 to the SSX genes on chromosome X leads to the formation of oncogenic fusion genes, which lead to initiation and proliferation of tumor cells. The detection and quantification of circulating tumor DNA (ctDNA) can serve as a non-invasive method for diagnostics of local or distant tumor recurrence, which could improve survival rates due to early detection., Methods: We developed a subtype-specific targeted next-generation sequencing (NGS) approach specifically targeting SS t(X;18)(p11;q11), which fuses SS18 ( SYT ) in chromosome 18 to SSX1 or SSX2 in chromosome x, and recurrent point mutations. In addition, patient-specific panels were designed from tumor exome sequencing. Both approaches were used to quantify ctDNA in patients' plasma., Results: The subtype-specific assay allowed detection of somatic mutations from 25/25 tumors with a mean of 1.68 targetable mutations. The minimal limit of detection was determined at a variant allele frequency of 0.05%. Analysis of 29 plasma samples from 15 tumor patients identified breakpoint ctDNA in 6 patients (sensitivity: 40%, specificity 100%). The addition of more mutations further increased assay sensitivity. Quantification of ctDNA in plasma samples ( n = 11) from one patient collected over 3 years, with a patient-specific panel based on tumor exome sequencing, correlated with the clinical course, response to treatment and tumor volume., Conclusions: Targeted NGS allows for highly sensitive tumor profiling and non-invasive detection of ctDNA in SS patients, enabling non-invasive monitoring of tumor dynamics.

Autologous fillet flaps are a common reconstructive option for large defects after forequarter amputation (FQA) due to advanced local malignancy or trauma. The inclusion of osseous structures into these has several advantages. This article therefore systematically reviews reconstructive options after FQA, using osteomusculocutaneous fillet flaps, with emphasis on personalized surgical technique and outcome. Additionally, we report on a case with an alternative surgical technique, which included targeted muscle reinnervation (TMR) of the flap. Our literature search was conducted in the PubMed and Cochrane databases. Studies that were identified were thoroughly scrutinized with regard to relevance, resulting in the inclusion of four studies (10 cases). FQA was predominantly a consequence of local malignancy. For vascular supply, the brachial artery was predominantly anastomosed to the subclavian artery and the brachial or cephalic vein to the subclavian or external jugular vein. Furthermore, we report on a case of a large osteosarcoma of the humerus. Extended FQA required the use of the forearm for defect coverage and shoulder contour reconstruction. Moreover, we performed TMR. Follow-up showed a satisfactory result and no phantom limb pain. In case of the need for free flap reconstruction after FQA, this review demonstrates the safety and advantage of osteomusculocutaneous fillet flaps. If the inclusion of the elbow joint into the flap is not possible, we recommend the use of the forearm, as described. Additionally, we advocate for the additional implementation of TMR, as it can be performed quickly and is likely to reduce phantom limb and neuroma pain.

Phagocytosis and the formation of reactive oxygen species (ROS) in phagocytic leukocytes are an effective killing mechanism of the innate host defense. These cellular processes of innate immunity function in a complex interplay with humoral factors. C-reactive protein (CRP) in its activated, monomeric isoform (mCRP) has been shown to activate immune cells via the classical complement pathway. We investigated the complement-dependent effects of monomeric CRP (mCRP) on neutrophils and monocyte subtypes using complement-specific inhibitors by both flow cytometry and confocal fluorescence microscopy. We demonstrate that CRP-induced ROS generation is a conformation-specific and complement-dependent process in leukocyte subsets with classical monocytes as the primary source of ROS amongst human monocyte subsets. Elucidation of this complex interplay of CRP and complement in inflammation pathophysiology might help to improve anti-inflammatory therapeutic strategies., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Zeller, Bogner, Kiefer, Braig, Winninger, Fricke, Karasu, Peter, Huber-Lang and Eisenhardt.)

Objective: Chronic neural implants require energy and signal supply. The objective of this work was to evaluate a multichannel transcutaneous coupling approach in an ex vivo split-concept study, which minimizes the invasiveness of such an implant by externalizing the processing electronics. Methods: Herein, the experimental work focused on the transcutaneous energy and signal transmission. The performance was discussed with widely evaluated concepts of neural interfaces in the literature. Results: The performance of the transcutaneous coupling approach increased with higher channel count and higher electrode pitches. Electrical crosstalk among channels was present, but acceptable for the stimulation of peripheral nerves. Conclusions: Transcutaneous coupling with extracorporeal transmitting arrays and subcutaneous counterparts provide a promising alternative to the inductive concept particularly when a fully integration of the system in a prosthetic shaft is intended. The relocation of the electronics can potentially prevent pressure sores, improve accessibility for maintenance and increase lifetime of the implant.

Background: Sarcomas are tumors of mesenchymal origin with high variation in anatomical localization. Sarcomas affecting the bone often require an interdisciplinary resection and reconstruction approach. However, it is critical that microsurgical reconstruction strategies do not negatively impact tumor safety and overall survival, as limb salvage is only the secondary goal of tumor surgery. Here, we analyzed the efficacy and safety of microsurgery in interdisciplinary treatment of sarcoma affecting the bone. Patients and Methods: We performed a retrospective chart review of all patients treated for soft-tissue and bone sarcoma at the senior author's institution with a focus on bone affection and microsurgical reconstruction between 2000 and 2019. This particular subgroup was further investigated for tumor resection status, 5-year survival rate, length of hospital stay, as well as overall complication and amputation rates. Results: Between 2000 and 2019, 803 patients were operated for sarcoma resection and reconstruction by the Department of Plastic and Hand Surgery. Of these, 212 patients presented with sarcoma of the extremity affecting the bone. Within this subgroup, 40 patients required microsurgical reconstruction for limb salvage, which was possible in 38 cases. R0 resection was achieved in 93.8%. The 5-year survival was 96.7%, and the overall complication rate was 25%, of which 40% were microsurgery associated complications. Conclusion: Safe and function-preserving treatment of soft-tissue and bone sarcoma is challenging. Primary reconstruction with microsurgical techniques of sarcoma-related defects enables limb-sparing and adequate oncosurgical cancer treatment without increasing the risk for local recurrence or prolonged hospital stay. The treatment of sarcoma patients should be reserved to high-volume centers with experienced plastic surgeon embedded in a comprehensive treatment concept., (Copyright © 2019 Zeller, Kiefer, Braig, Winninger, Dovi-Akue, Herget, Stark and Eisenhardt.)

C-reactive protein (CRP) is a member of the pentraxin superfamily that is widely recognized as a marker of inflammatory reactions and cardiovascular risk in humans. Recently, a growing body of data is emerging, which demonstrates that CRP is not only a marker of inflammation but also acts as a direct mediator of inflammatory reactions and the innate immune response. Here, we critically review the various lines of evidence supporting the concept of a pro-inflammatory "CRP system." The CRP system consists of a functionally inert circulating pentameric form (pCRP), which is transformed to its highly pro-inflammatory structural isoforms, pCRP* and ultimately to monomeric CRP (mCRP). While retaining an overall pentameric structure, pCRP* is structurally more relaxed than pCRP, thus exposing neoepitopes important for immune activation and complement fixation. Thereby, pCRP* shares its pro-inflammatory properties with the fully dissociated structural isoform mCRP. The dissociation of pCRP into its pro-inflammatory structural isoforms and thus activation of the CRP system occur on necrotic, apoptotic, and ischemic cells, regular β-sheet structures such as β-amyloid, the membranes of activated cells (e.g., platelets, monocytes, and endothelial cells), and/or the surface of microparticles, the latter by binding to phosphocholine. Both pCRP* and mCRP can cause activation of platelets, leukocytes, endothelial cells, and complement. The localization and deposition of these pro-inflammatory structural isoforms of CRP in inflamed tissue appear to be important mediators for a range of clinical conditions, including ischemia/reperfusion (I/R) injury of various organs, cardiovascular disease, transplant rejection, Alzheimer's disease, and age-related macular degeneration. These findings provide the impetus to tackle the vexing problem of innate immunity response by targeting CRP. Understanding the "activation process" of CRP will also likely allow the development of novel anti-inflammatory drugs, thereby providing potential new immunomodulatory therapeutics in a broad range of inflammatory diseases.

Introduction: C-reactive protein circulates as a pentameric protein (pCRP). pCRP is a well-established diagnostic marker as plasma levels rise in response to tissue injury and inflammation. We recently described pro-inflammatory properties of CRP, which are mediated by conformational changes from pCRP to bioactive isoforms expressing pro-inflammatory neo-epitopes [pCRP* and monomeric C-reactive protein (mCRP)]. Here, we investigate the role of CRP isoforms in renal ischemia/reperfusion injury (IRI)., Methods: Rat kidneys in animals with and without intraperitoneally injected pCRP were subjected to IRI by the time of pCRP exposure and were subsequently analyzed for monocyte infiltration, caspase-3 expression, and tubular damage. Blood urea nitrogen (BUN) was analyzed pre-ischemia and post-reperfusion. CRP effects on leukocyte recruitment were investigated via intravital imaging of rat-striated muscle IRI. Localized conformational CRP changes were analyzed by immunohistochemistry using conformation specific antibodies. 1,6-bis(phosphocholine)-hexane (1,6-bisPC), which stabilizes CRP in its native pentameric form was used to validate CRP effects. Leukocyte activation was assessed by quantification of reactive oxygen species (ROS) induction by CRP isoforms ex vivo and in vitro through electron spin resonance spectroscopy. Signaling pathways were analyzed by disrupting lipid rafts with nystatin and subsequent ROS detection. In order to confirm the translational relevance of our findings, biopsies of microsurgical human free tissue transfers before and after IRI were examined by immunofluorescence for CRP deposition and co-localization of CD68 + leukocytes., Results: The application of pCRP aggravates tissue damage in renal IRI. 1,6-bisPC reverses these effects via inhibition of the conformational change that leads to exposure of pro-inflammatory epitopes in CRP (pCRP* and mCRP). Structurally altered CRP induces leukocyte-endothelial interaction and induces ROS formation in leukocytes, the latter can be abrogated by blocking lipid raft-dependent signaling pathways with Nystatin. Stabilizing pCRP in its native pentameric state abrogates these pro-inflammatory effects. Importantly, these findings are confirmed in human IRI challenged muscle tissue., Conclusion: These results suggest that CRP is a potent modulator of IRI. Stabilizing the native pCRP conformation represents a promising anti-inflammatory therapeutic strategy by attenuation of leukocyte recruitment and ROS formation, the primary pathomechanisms of IRI.

C-reactive protein (CRP) concentrations rise in response to tissue injury or infection. Circulating pentameric CRP (pCRP) localizes to damaged tissue where it leads to complement activation and further tissue damage. In-depth knowledge of the pCRP activation mechanism is essential to develop therapeutic strategies to minimize tissue injury. Here we demonstrate that pCRP by binding to cell-derived microvesicles undergoes a structural change without disrupting the pentameric symmetry (pCRP*). pCRP* constitutes the major CRP species in human-inflamed tissue and allows binding of complement factor 1q (C1q) and activation of the classical complement pathway. pCRP*-microvesicle complexes lead to enhanced recruitment of leukocytes to inflamed tissue. A small-molecule inhibitor of pCRP (1,6-bis(phosphocholine)-hexane), which blocks the pCRP-microvesicle interactions, abrogates these proinflammatory effects. Reducing inflammation-mediated tissue injury by therapeutic inhibition might improve the outcome of myocardial infarction, stroke and other inflammatory conditions.

Background: Synovial sarcoma account for approximately 10 % of all soft-tissue tumors and occur most frequently in young adults. A specific translocation in this sarcoma induces fusion of the SYT gene on chromosome 18 to the SSX genes on chromosome X, leading to proliferation of the tumor cells. The need for non-invasive biomarkers indicating recurrence and activity of this disease has sparked research into short non-coding RNA known as microRNA (miRNA)., Methods: Blood samples of patients with active synovial sarcoma and of synovial sarcoma patients in complete remission as well as of healthy donors and patients with active leiomyosarcoma, MPNST, Ewing sarcoma and liposarcoma were collected. Whole blood RNA was extracted and samples of patients with active synovial sarcoma and of healthy donors were analyzed using an Affymetrix GeneChip miRNA Array v. 4.0. qRT-PCR was carried out to confirm a panel of miRNAs which where differentially expressed in the miRNA array. This miRNA-panel was further evaluated in patients with synovial sarcoma in complete remission and patients with active leiomyosarcoma, MPNST, Ewing sarcoma and liposarcoma as well as in an independent cohort of synovial sarcoma patients., Results: Unsupervised hierarchical clustering of the miRNA arrays separated patients with active synovial sarcoma from healthy controls. A panel of seven miRNAs (miR-99a-5p, miR-146b-5p, miR-148b-3p, miR-195-5p, miR-223-3p, miR-500b-3p and miR-505-3p) was further validated by qRT-PCR to be significantly upregulated in synovial sarcoma patients. Moreover, most of the analyzed miRNAs were shown to be significantly upregulated in synovial sarcoma patients compared to leiomyosarcoma, MPNST, Ewing sarcoma and liposarcoma patients. Validation of the miRNA panel in an independent cohort of synovial sarcoma patients confirmed higher expression levels compared to healthy controls and patients in complete remission., Conclusion: Our results have identified a specific whole blood miRNA signature that may serve as an independent biomarker for the diagnosis of local recurrence or distant metastasis of synovial sarcoma. It even distinguishes synovial sarcoma from other sarcoma subtypes, thus potentially serving as a specific biomarker for synovial sarcoma.

In contrast to triquetral fractures, dislocations of the triquetrum are very uncommon because of the very strong ligamentous support. They occasionally occur in association with complex wrist injuries, isolated dislocations however are extremely rare. We report a case of a male athlete who sustained an isolated volar dislocation of the triquetrum. The injury was treated by open reduction, fixation with Kirschner-wires and direct repair of torn ligaments. Kirschner-wires were removed after 6 weeks and physiotherapy was started. At 3 years follow-up he reported to be free of pain and showed only slightly restricted grip strength and range of motion when compared to his uninjured hand. A review of the literature indicates that final outcomes are usually satisfactory if prompt diagnosis and treatment occurs. However persistent pain and impaired hand function may result because of delayed diagnosis or insufficient repair of associated ligament injuries.

Tissue damage in burn injury leads to a rapid increase of leukocytes and acute phase reactants. Plasma levels of C-reactive protein (CRP) rise within hours after the insult. No deficiency of this protein has been reported in humans, suggesting it plays a pivotal role in innate immunity. CRP in circulation is composed of five identical subunits [pentameric CRP (pCRP)]. Recently, deposits of structurally modified CRP (mCRP) have been found in inflammatory diseases. Little is known about this structural change and how it affects CRP functions. We analyzed CRP deposits in burn wounds and serum by immunohistochemistry, western blot and dot blot analysis. CRP was deposited in necrotic and inflamed tissue, but not in adjacent healthy tissue. Tissue deposited CRP was detected by mCRP-specific antibodies and structurally different from serum pCRP. mCRP but not pCRP induced reactive oxygen species production by monocytes and facilitated uptake of necrotic Jurkat cells by macrophages. In addition, it accelerated migration of keratinocytes in a scratch wound assay. The structural changes that occur in pCRP upon localization to damaged and inflamed tissue in burn wounds result in a functionally altered protein with distinct functions. mCRP exhibits opsonic, proinflammatory and promigratory properties which modulate wound healing., (© The Japanese Society for Immunology. 2014. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Background: The relevance of the dissociation of circulating pentameric C-reactive protein (pCRP) to its monomeric subunits (mCRP) is poorly understood. We investigated the role of conformational C-reactive protein changes in vivo., Methods and Results: We identified mCRP in inflamed human striated muscle, human atherosclerotic plaque, and infarcted myocardium (rat and human) and its colocalization with inflammatory cells, which suggests a general causal role of mCRP in inflammation. This was confirmed in rat intravital microscopy of lipopolysaccharide-induced cremasteric muscle inflammation. Intravenous pCRP administration significantly enhanced leukocyte rolling, adhesion, and transmigration via localized dissociation to mCRP in inflamed but not noninflamed cremaster muscle. This was confirmed in a rat model of myocardial infarction. Mechanistically, this process was dependent on exposure of lysophosphatidylcholine on activated cell membranes, which is generated after phospholipase A2 activation. These membrane changes could be visualized intravitally on endothelial cells, as could the colocalized mCRP generation. Blocking of phospholipase A2 abrogated C-reactive protein dissociation and thereby blunted the proinflammatory effects of C-reactive protein. Identifying the dissociation process as a therapeutic target, we stabilized pCRP using 1,6-bis(phosphocholine)-hexane, which prevented dissociation in vitro and in vivo and consequently inhibited the generation and proinflammatory activity of mCRP; notably, it also inhibited mCRP deposition and inflammation in rat myocardial infarction., Conclusions: These results provide in vivo evidence for a novel mechanism that localizes and aggravates inflammation via phospholipase A2-dependent dissociation of circulating pCRP to mCRP. mCRP is proposed as a pathogenic factor in atherosclerosis and myocardial infarction. Most importantly, the inhibition of pCRP dissociation represents a promising, novel anti-inflammatory therapeutic strategy., (© 2014 American Heart Association, Inc.)

Protein insertion into the bacterial inner membrane is facilitated by SecYEG or YidC. Although SecYEG most likely constitutes the major integration site, small membrane proteins have been shown to integrate via YidC. We show that YidC can also integrate multispanning membrane proteins such as mannitol permease or TatC, which had been considered to be exclusively integrated by SecYEG. Only SecA-dependent multispanning membrane proteins strictly require SecYEG for integration, which suggests that SecA can only interact with the SecYEG translocon, but not with the YidC insertase. Targeting of multispanning membrane proteins to YidC is mediated by signal recognition particle (SRP), and we show by site-directed cross-linking that the C-terminus of YidC is in contact with SRP, the SRP receptor, and ribosomal proteins. These findings indicate that SRP recognizes membrane proteins independent of the downstream integration site and that many membrane proteins can probably use either SecYEG or YidC for integration. Because protein synthesis is much slower than protein transport, the use of YidC as an additional integration site for multispanning membrane proteins may prevent a situation in which the majority of SecYEG complexes are occupied by translating ribosomes during cotranslational insertion, impeding the translocation of secretory proteins.

Protein targeting by the signal recognition particle (SRP) and the bacterial SRP receptor FtsY requires a series of closely coordinated steps that monitor the presence of a substrate, the membrane, and a vacant translocon. Although the influence of substrate binding on FtsY-SRP complex formation is well documented, the contribution of the membrane is largely unknown. In the current study, we found that negatively charged phospholipids stimulate FtsY-SRP complex formation. Phospholipids act on a conserved positively charged amphipathic helix in FtsY and induce a conformational change that strongly enhances the FtsY-lipid interaction. This membrane-bound, signal sequence-independent FtsY-SRP complex is able to recruit RNCs to the membrane and to transfer them to the Sec translocon. Significantly, the same results were also observed with an artificial FtsY-SRP fusion protein, which was tethered to the membrane via a transmembrane domain. This indicates that substrate recognition by a soluble SRP is not essential for cotranslational targeting in Escherichia coli. Our findings reveal a remarkable flexibility of SRP-dependent protein targeting, as they indicate that substrate recognition can occur either in the cytosol via ribosome-bound SRP or at the membrane via a preassembled FtsY-SRP complex.